Institute of Sound and Vibration Research · descriptions of the activities and work of the four...

Institute of Sound and Vibration Research Annual Report 2002

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Contents Page Directorate and Administration .................................................................................................................................. 2 Scientific Advisory Committee .................................................................................................................................. 3 Editor’s Preface .......................................................................................................................................................... 4

Director’s Report........................................................................................................................................................ 5 Financial Report ......................................................................................................................................................... 7 Resources and Facilities ........................................................................................................................................... 10 Staff of the Institute .................................................................................................................................................. 11

1. RESEARCH......................................................................................................................................................... 19 Introductory Remarks........................................................................................................................................... 19 1.1 Dynamics Group............................................................................................................................................. 20

List of Research Projects................................................................................................................................ 24 Publications.................................................................................................................................................... 26

1.2 Fluid Dynamics and Acoustics Group............................................................................................................ 31 List of Research Projects................................................................................................................................ 37 Publications..................................................................................................................................................... 40

1.3 Human Sciences Group.................................................................................................................................. 44 List of Research Projects................................................................................................................................ 50 Publications.................................................................................................................................................... 52

1.4 Signal Processing and Control Group ........................................................................................................... 56 List of Research Projects................................................................................................................................ 62 Publications.................................................................................................................................................... 64

2. TEACHING ......................................................................................................................................................... 69 Introductory Remarks........................................................................................................................................... 69 2.1 Undergraduate Courses .................................................................................................................................. 70 2.2 MSc and Diploma Courses............................................................................................................................. 71 2.3 Continuing Education..................................................................................................................................... 73 2.4 ISVR Short Courses ....................................................................................................................................... 74 2.5 International Collaboration............................................................................................................................. 75

3. CONSULTANCY................................................................................................................................................ 76 3.1 ISVR Automotive Design Advisory Unit....................................................................................................... 76 3.2 ISVR Consultancy Services ........................................................................................................................... 79

Appendix 1 Academic Awards and Student Prizes.............................................................................................. 82 Appendix 2 Students ............................................................................................................................................ 88 Appendix 3 Extramural Appointments................................................................................................................. 91 Appendix 4 Lectures and Seminars...................................................................................................................... 95 Appendix 5 Research Publication Statistics......................................................................................................... 96 Appendix 6 External Examiners .......................................................................................................................... 97 Appendix 7 List of Formal International Links ................................................................................................... 98 Appendix 8 Principal Intramural Responsibilities of Staff and Student Representatives .................................... 99 Appendix 9 Acknowledgements of Research Sponsors..................................................................................... 102 Appendix 10 Honours, Awards, Medals .............................................................................................................. 103

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Directorate and Administration Director .........................................................................................................................Professor P A Nelson Research Group Chairmen

Dynamics ..........................................................................................................Dr M J Brennan Fluid Dynamics and Acoustics .........................................................................Professor C L Morfey Human Sciences................................................................................................Professor M J Griffin Signal Processing and Control.........................................................................Professor S J Elliott

Consultancy Unit Managers Automotive Design Advisory Unit ....................................................................Mr J D Dixon ISVR Consultancy Services...............................................................................Mr S J C Dyne

Hearing and Balance Centre .......................................................................................Professor M E Lutman Academic and Departmental Secretary .....................................................................Mrs M Z Strickland Resource Manager .......................................................................................................Mr J Taylor Financial Controller .....................................................................................................Mr J Sturgess Financial Assistant .......................................................................................................Mrs M A Perkins Librarian .......................................................................................................................Ms A M Gunn Computer Network Manager ......................................................................................Mr J A Haughton Departmental Programmer .........................................................................................Mrs G A Jewell Enquiries:

Telephone................................................... +44 (0)23 8059 2294

Fax ............................................................. +44 (0)23 8059 3190

Email.......................................................... [email protected]

Telex........................................................... 86626 MY NEWS

ISVR Website ............................................. http://www.isvr.soton.ac.uk/

mailto:[email protected]

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Scientific Advisory Committee (at 30.04.02)

Ex-Officio Members The Vice-Chancellor A Deputy Vice-Chancellor The Dean of the Faculty of Engineering and Applied Science The Director, ISVR (Chairman)

External Members Mr B F Berry National Physical Laboratory, Teddington Professor B L Clarkson Former Director of ISVR Dr S H Cole Scientific Adviser, Northern Ireland Dr B J Dobson Devonport Management Limited Dr J H Foxwell Defence Consultant Professor N A Halliwell Loughborough University Dr G J Heald QinetiQ, Winfrith Mr B Hemsworth European Rail Research Institute Professor K H Heron QinetiQ, Farnborough Dr E Hylton Engineering & Physical Sciences Research Council Dr A J Kempton Rolls-Royce plc, Derby Mr C F McCulloch Consultant Dr R Preston National Physical Laboratory Dr I Proudler QinetiQ, Malvern Professor E Stansfield Thales Research, Reading Professor Q Summerfield MRC Institute of Hearing Research Mr D M Wells GKN Westland Helicopters Ltd, Yeovil

ISVR Members Professor R Allen Professor M E Lutman Professor R J Astley Dr B R Mace Dr M J Brennan Emeritus Professor D J Mead Emeritus Professor P O A L Davies Professor C L Morfey Mr J D Dixon Mr K J Munro Emeritus Professor P E Doak Emeritus Professor M Petyt Mr S J C Dyne Dr B Rafaely Professor S J Elliott Emeritus Professor C G Rice Ms J Eyles Mr J Sturgess Emeritus Professor F J Fahy Dr D J Thompson Dr M J Fisher (Secretary) Visiting Senior Lecturer Dr J G Walker Professor M J Griffin Dr P R White Professor T G Leighton

University Members Dr P R Birkin Department of Chemistry Emeritus Professor R Holmes School of Engineering Sciences Emeritus Professor G M Lilley School of Engineering Sciences Dr J W McBride School of Engineering Sciences

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Editor’s Preface The main body of this report inclusively covers the period from May 2001 to April 2002. This material includes descriptions of the activities and work of the four research groups and two consultancy units, ISVR Consultancy Services and ADAU. The report of the Hearing and Balance Centre, which covers the work of the South of England Cochlear Implant Centre, as well as audiological research, is included in the report of the Human Sciences Group. In conformity with the University procedure, publications listed at the end of the respective sections, and the summary of publication statistics in Appendix 5, cover the calendar year 2001. The list of academic awards (Appendix 1) covers the conferment of doctorates awarded at various times during the academic session September 2001 to July 2002, as well as Masters and Diploma awards and First Degrees awarded in July 2002. I have again been assisted in the preparation and editing of this report by Mrs Sue Brindle. Sue has cheerfully and efficiently performed the tasks which I make no apology for listing again this year: namely, sending out the initial requests for submissions, chasing the delinquents who missed deadlines, assembling the responses for my attention, deciphering my extensive editorial annotation, amending the reports accordingly and finally putting together the document which you have before you. I wish to express my appreciation of her help which greatly eased my task. I would like to thank those colleagues who contributed material for the report and the members of the secretarial staff who prepared it for submission. Any errors, omissions or oversights may be laid at my door. Suggestions for improvement of the format or structure of the report are most welcome.

FJF August 2002

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Director’s Report It is a great pleasure to open this year’s Director’s Report by reporting that the ISVR was awarded the grade of 5* in the 2001 Research Assessment Exercise, which is a great tribute to the efforts of all the staff of the Institute. Particular thanks go to my predecessor, Professor J K Hammond, for the major role he has played in guiding the Institute to this outstanding result and the particular care which he took in preparing the RAE submission. The Institute was returned in a joint submission with the School of Engineering Sciences to Unit of Assessment 30 (Mechanical, Aeronautical and Production Engineering). Only five other Universities, out of a total of 47 in this Unit of Assessment, were awarded the 5* accolade. These were Imperial College London, The Queen’s University of Belfast, and the Universities of Leeds, Liverpool and Bath. The past year has been a time of great change within our University. The new Vice Chancellor, Professor Bill Wakeham, introduced his ‘Vision’ for the University of Southampton for the year 2010 and beyond. The vision was introduced to the senior staff of the University in January 2002 following a number of consultative meetings. These plans were then the subject of wide consultation throughout the University; with some modifications, they received final approval by Senate and Council during the summer of 2002. Broadly speaking, the vision sets out the strategy for achieving the University’s aim to be among the top ten most highly regarded Universities in the UK. It is the objective to conduct research of world class in areas of established activity and rapidly to grow new areas of research to that level. It is also intended to maintain a broad subject base and to become renowned for addressing large multi-disciplinary problems. Enterprise and innovation are also to be a strong theme in our activities. Major changes to the operation of the University are to be implemented from August 2003 in order to facilitate the delivery of the vision. The University will be managed through three major faculties: a Faculty of Engineering, Science and Mathematics; a Faculty of Medicine, Health and Life Sciences; and a Faculty of Arts, Humanities, Law and Social Sciences. Each Faculty will comprise a number of Schools. ISVR is to have the status of a School in the Faculty of Engineering, Science and Mathematics. The other Schools in the Faculty are to be those of Chemistry, Physics, Mathematics, Geography, Ocean and Earth Sciences, Civil Engineering and Environmental Technology, Engineering Sciences, Electronics and Computer Science. At the time of writing, we await the appointment of the new Dean of this Faculty, who should take up their position in October 2002. It is envisaged that there will be a transitional year until August 2003, when the existing management structure will continue to be run whilst the new structure is evolved. The fundamental rationale behind this change in structure is to enhance the communication between Schools and the centre of the University, where Deans will reside. This is intended, in particular, to enhance the strategic planning process associated with the fulfilment of the objectives outlined in the Vice-Chancellor’s vision. It is a tribute to the efforts of the ISVR staff, both past and present, to be recognised as a School within this new structure. We await its further development with interest. A major task during the past year has been the development of a strategic plan for the Institute for the next five years. The senior staff of the Institute have been fully involved in this process and have agreed a document which was submitted to the University as part of this year’s strategic planning round. The principal objective is to continue to strengthen the ISVR’s research profile through a programme of appointments of new staff and the funding of existing staff from the HEFCE allocation. With regard to learning and teaching, the strategy is to focus provision at undergraduate level on an in-depth MEng programme in acoustical engineering. Moves have also been made towards the funding of an undergraduate course in audiology and it is intended to develop this course in parallel with the existing MSc programme in this subject area. At Masters level, the intention is to continue to pursue the efficient integration of MSc courses with the provision of short courses for industry. If the plans for the future of the Institute are to be successfully implemented, it will be vital for the ISVR to be fully rewarded in the long term for its performance in the Research Assessment Exercise. In the immediate future, the University has agreed an increase in our HEFCE allocation, but the new resource allocation model that is being proposed together with the revised University structures is eagerly awaited. Turning to the staff of the Institute, it is a pleasure to report the appointment of Dr David Simpson to a Lectureship in Biomedical Signal Processing in the ISVR. Dr Simpson will be responsible for the organisation and delivery of our new modular Masters Training Package in Biomedical Signal Processing. As reported last year, Dr Antonello De Stefano has also been appointed as Course Co-ordinator. At the time of writing, the first

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module in the programme has been launched and run successfully. With the new University management structure about to be formed, the control of the Institute’s finances becomes even more important if we are to maintain School status and function effectively within the new Faculty. It is therefore timely to report the appointment of Mr James Sturgess as financial controller in the ISVR. James, working closely with Mrs Gill Jewell, has already succeeded in introducing a new network-based accounting system which will form the basis of our future budgetary control system. Notable retirements that have taken place during the reporting period include those of Mr Bob Davies, who was Technical Manager of the ISVR Consultancy Services for 11 years, together with Mr Jeff Baker, Mr Yanis Erotokritos and Mr George Bazeley of the Automotive Design Advisory Unit. Jeff, Yanis and George were members of the Institute for 31, 29 and 32 years, respectively. Last year has also seen the retirement of Graham King, electronics technician of our Electronics Workshop, who contributed 12 years of service to the ISVR. We wish them all long and happy retirements.

P A Nelson August 2002

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Financial Report Professor P A Nelson

Income to the ISVR fell slightly during the last financial year to approximately £7.5M from the record level of £7.9M reached during the financial year 1 August 2000 to 31 July 2001. Comparison with the previous year’s figures shows that there has been a fall in income to services rendered accounts, the most notable change being services rendered on behalf of UK industry. This figure has fallen from £874k to £423k. There was also a slight fall in trading account income both in the ISVR Consultancy Services and in the Automotive Design Advisory Unit (ADAU), the income to ISVR Consultancy Services falling from £751k to £481 and the income to ADAU falling from £520k to £450k. Whilst much of the fall in consultancy income is associated with reduction in staff numbers in ISVR Consultancy Services, the ADAU has continued to suffer from the current difficulties in the automotive industry that are being experienced on a global scale by several major clients. The fall in services rendered income may also be associated with more stringent financial conditions faced by UK industry. The South of England Cochlear Implant Centre (SOECIC), however, increased their turnover by £200k and has had a very successful year. Turning to research, there has been a healthy increase in research contract income from £1.87M during the last financial year to £2.2M. A notable increase is in the level of Research Council income, from £572k to £788k. Whilst this is a very positive trend, it will be vital during the next financial year to maintain a high rate of submission of top quality research proposals to the Research Councils, especially in view of the highly competitive nature of the grant awarding process. In the meantime, the General Account through which HEFCE associated funding is distributed, contributed of the order of £2M to the Institute’s income, this being a very similar figure to the previous financial year. We look forward to a substantial increase in this funding during the current financial year as a consequence of the ISVR’s outstanding performance in the Research Assessment Exercise. However, despite the fact that the University of Southampton produced exceptionally good results in the most recent RAE, the inability of HEFCE to fully fund the overall increase in research performance in the Higher Education sector has meant some “smoothing” of the HEFCE allocations at University level. Nevertheless, the increased funding that has been allocated should help to stabilise ISVR finances and pave the way for further development of the Institute. Overall, expenditure exceeded income during the financial year. A large component of this was associated with the spending of reserves in services rendered accounts held by the research groups, much of this spend being associated with the salaries of staff who will be funded from the HEFCE budget during the forthcoming financial year. It is also worth noting, however, that both ICS and ADAU produced a net loss to the ISVR economy and it is essential that this matter is addressed during the forthcoming year.

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Income: 1 August 2001 – 31 July 2002

General Account £ HEFCE − Teaching 649,800 HEFCE − Research 1,240,900 HEFCE − Equipment 62,400 Faculty Loan 100,000 Less: repayment of previous

Faculty Loan (33,300)

2,019,800

Research Contracts Research Councils 788,766 UK Government 69,301 UK Industry 680,247 EU – Government 479,546 EU – Other 57,419 Overseas 121,940 UK Charities 11,915 2,209,134

Trading Accounts ICS 481,868 ADAU 449,749 SOECIC 1,274,958 2,206,575

Services Rendered Research Councils 142,999 UK Government, Health 6,500 UK Industry 423,118 UK Universities 884 EU – Government 17,901 EU – Other 0 Overseas 21,665 Royalties 53 Other 51,151 664,271

Other Short courses 179,204 Donations 22,820 Subventions 0 RTSG 40,220 Doctoral Training Accounts 25,397 Other 132,110 399,751

Total Income 7,499,531

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Expenditure: 1 August 2001 – 31 July 2002

General Account £ Salaries HEFCE 808,028 Overhead Reserve 355,604 Wages Reserve (121,282) 1,042,350 Operational Costs HEFCE 120,399 Overhead Reserve 8,404 Wages Reserve (9,022) Equipment Grant 20,430 140,211

Other costs (incl electricity, etc) 115,112 1,297,673 Staff driver 559,100 Student driver 227,500 Space driver 639,800 1,426,400

Research Contracts Research Councils 602,349 UK – Government 54,962 UK – Industry 506,538 EU – Government 409,446 EU – Other 40,692 Overseas 77,562 Charities 11,721 1,703,270

Trading Accounts ICS 444,354 ADAU 440,260 SOECIC 1,068,821 1,953,435

Services Rendered 927,632

Other Short courses 128,573 Donations 62,174 Subventions 0 RTSG 368,900 Doctoral Training Accounts 18,892 Other 21,018 599,557

Total Expenditure 7,907,967

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Resources and Facilities Professor P A Nelson

Resources and Facilities Considerable effort has been made during the last year to make optimal use of our office and laboratory space. In view of the high cost of space that is reflected in the University and Engineering Faculty resource allocation models, every effort has been made to dispose of those areas which have hitherto not been efficiently utilised. A major component of our strategy has been the withdrawal from a large part of Building 19. This has been enabled by the refurbishment of the Rayleigh Building engine test cell area. Since this had not been used for engine testing for some time, the decision was taken to convert this into a general purpose dynamics laboratory. The conversion work was completed in January 2002 at a relatively modest cost to the Department which will be recouped in full during the next financial year as a consequence of relinquishing the area in Building 19. In the longer term, a strategy involving the provision of a new building on the site of the existing Building 19 is envisaged and has been the subject of considerable discussion within the University. A plan for such a building had previously been drawn up for submission to the Joint Infrastructure Fund although the associated bid was not successful. The building plans incorporate space for audiological research and research into vehicle dynamics. The continued success of the South of England Cochlear Implant Centre and the prospect of a further expansion of our teaching and research in Audiology further prompts the need for a new building. These requirements have been viewed sympathetically by the University and discussions with the University Development Office suggest that fund-raising activities in this area may prove fruitful. This possibility is currently being actively pursued. Discussions are also under way within the University regarding the future of the Chilworth Laboratories, which occupy a site of some value within the Chilworth Science Park. The long-term aim of relocating our research activity in automotive dynamics to the main site remains under discussion.

Computing Resources The new ISVR computing network was successfully commissioned during the Autumn of 2001. The previous network was becoming incapable of coping with the traffic associated with the large number (now over 200) of personal computers which are currently in operation within the Institute. Although the transition to the new system was not an easy one, there have been almost no instances of network failure since the time of installation. Great thanks are due to Jon Haughton and John Taylor for managing this difficult process and for producing such a successful outcome. Finally, thanks are again due to Mr John Taylor, our Resource Manager, for his continued enthusiastic and dedicated management of the technical operation of the department.

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Staff of the Institute (at 30.04.02)

Academic Staff Group Affiliation D – Dynamics Group F – Fluid Dynamics and Acoustics Group H – Human Sciences Group S – Signal Processing and Control Group

Professors R Allen, BSc, PhD, CEng, FIEE, FIMechE, FIPEM (Professor of Biodynamics and Control) S R J Astley, BSc, MSc, PhD, DEng, FIPENZ, FRSNZ (Professor of Computational Acoustics) F S J Elliott, BSc, PhD, SMIEEE, FIEE (Professor of Adaptive Systems) S M J Griffin, BSc, PhD (Professor of Human Factors) H J K Hammond, BSc, PhD (Professor of Signal Analysis) S T G Leighton, BA, MA, PhD, CPhys, FInstP, FIOA, FASA (Professor of Ultrasonics and Underwater Acoustics) F M E Lutman, BSc, MSc, PhD (Professor of Audiology) H C L Morfey, MA, MSc(Eng), PhD, FIOA, FASA (Professor of Applied Mechanics and Biomechanics) F P A Nelson, BSc, PhD, CEng, FIMechE, MIEEE, FIOA (Professor of Acoustics) F

Readers M J Fisher, BSc, PhD, FIOA (Rolls-Royce Reader) F B R Mace, MA, DPhil (Reader in Structural Dynamics) D

D J Thompson, BA, MA, PhD, CEng, MIMechE, FIOA (Reader in Railway Noise and Vibration) D

Senior Lecturers M J Brennan, BA, MSc, PhD, CEng, FIMechE, FIOA D

B Rafaely, BSc, MSc, PhD, MBA Management S

P R White, BSc, PhD S

Lecturers N S Ferguson, BSc, PhD D I H Flindell, BSc, MSc, PhD, PGCE, MIOA (part-time) H P Gardonio, Laurea in Ing Meccanica, PhD, CEng S K R Holland, BSc, PhD, MIOA F C J C Jones, BSc, PhD, MIOA D P F Joseph, BSc, MSc, PhD F S Kapadia, BEng, MEng, PhD H A McAlpine, BSc, PhD F D M Simpson, BSc, PhD S T P Waters, BSc, PhD D M C M Wright, BEng, PhD, MIOA F

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Associated Academic Staff (at 30.04.02)

Emeritus Professors P O A L Davies, BE, PhD, FIMechE, CEng, MIOA F M Petyt, BSc, MSc, PhD, CMath, FIMA, FIOA, FIIAV D P E Doak, BS, BA, MS, FIOA, FASA, FIIAV F

F J Fahy, BSc(Eng), PhD, HonFIOA F C G Rice, BSc, MSc, HonMD, CEng, FIEE, CPhys, FInstP,

FIOA H D J Mead, PhD, DSc, DCAe, CEng, FRAeS D R G White, PhD, DSc, FREng, CEng, FIOA D

Visiting Professors N A Halliwell, BSc, PhD, DSc, FEng, CEng, FIMechE,

CPhys, FInstP, FSPIE 3 A R D Thornton, BSc, PhD, CEng, MIERE, MBCS, MIEE 4

S M Braun, BSc, MSc, DSc 1 M J Buckingham, BSc, PhD, FIOA 2 R C Chivers, MA, PhD, DSc, CPhys, CMath, CEng,

FInstP, FIMA, FIPEM, FinstNDT, FACPSM

J D Turner, BSc(Phys), PhD, CEng, MIEE, MInstP 5

Visiting Senior Lecturers G Heald, BA MPhil PhD FIOA6 A M Martin, BSc, MSc, PhD, FIOA H N Lalor, BSc(Eng), MSc, PhD D J G Walker, BSc, PhD, CPhys, MInstP, FIOA H

Visiting Lecturer D Anderton, BTech, MSc(Eng), PhD, CEng, MIMechE F 1 Technion, Haifa

2 Scripps Institute of Oceanography

3 University of Loughborough

4 MRC Institute of Hearing Research

5 Transport Research Laboratory

6 QinetiQ, Winfrith

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Research Staff (at 30.04.02)

Senior Research Fellows C H Lewis, BSc, MSc, PhD, MErgS H R J Pinnington, BSc, MSc, PhD D J M Muggleton, BSc(Eng), PhD, ACGI D

Research Fellows H Abulula, BSc, MSc, PhD S X Huang, BSc, MSc, PhD, ASME S A Barney, BSc, MSc, PhD, ILTM S E R Hughes, BEng, MSc, PhD, AMIEE F T Bravo, Dipl Phys, PhD S B W Lawton, BS, MSc, DipSoton, MIOA H W B Collis, BEng, PhD S (Associate) Y-S Lee, BSc, MSc, PhD S A De Stefano, ChElecEng(Napoli), PhD, CEng, MIEEE, MIOA S

C Maury, Dipl MEng, PhD S

M Morioka, BSc, PhD H W G Dewar, BEng, MS, PhD F Y Qiu, BSc, MSc, PhD H

Z Feng, BEng, MSc, PhD S R H Self, BSc, MSc, PhD F R M Grice, BSc, MSc, PhD, CEng, MIMechE D J-S Seo, BS, MSc PhD S H V C Howarth, BSc, PhD H T X Wu, BEng, MSc, PhD D

Research Assistants A L Bassetti, Dottore * F M O’Boyle, MPhys * H J P Battaner-Moro, BSc, MSc * F K Papanagiotou, BEng, MSc, AMIOA, AMIEE * S O Baumann, MEng * S X Sheng, BSc, MSc, PhD D A S T B Blake, MPhys F M D Simpson, BSc F X Chen, BSc, MSc, PhD F A Thite, BEng, MTech D T P Gunston, BSc * H M G R Toward, BEng, MSc * H J A Hamilton, BE * F A J L Welsh, BSc, MSc * H

J Mendoza-Lopez, BSc, MSc D D Whitehouse, BSc, MSc * H

A Monk-Steel, BEng, MSc, AmIMechE * D M Wilkinson, BEng * F S Notley, MEng S C Williams, MEng * F

Visiting Researchers M Bai, BSc, MSc, PhD S 1 N J Kessissoglou, BEng, PhD S 2 G Brown D S Kijimoto, BEng, MSc, PhD F 3 J K Dix, BSc, PhD F 1 J-T Kim, BS, MS, PhD, PE F 3 C R Halkyard, BSc, BE, PhD D T Kitagawa, BEng, MSc D A Houmat, MSc, PhD D 1 X L Laparra, BSc F S Ishimitsu, PhD S 1

Visiting Academic 2

Visiting Lecturer 3

Visiting Research Fellow

Associate Consultant B J Tester, BSc, MSc, PhD F

* Registered as Research Student (MPhil/PhD)

Staff who have left during the year are shown in italics

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Consultancy Units (at 30.04.02)

Automotive Design Advisory Unit (ADAU) ISVR Consultancy Services

Manager Manager J D Dixon, BSc S J C Dyne, BA, PGCE, Eur Ing, MRAeS, MIOA, CEng

Technical Manager R A Davis, BSc(Eng), MIOA

Deputy Manager M G Smith, BSc, MSc, MIOA*

Senior Engineers Senior Engineers J M Baker, MPhil R D Rawlinson, BSc, MSc, CEng, FIOA N R Erotokritos, MSc(Eng), CEng, MIMarE

Engineers Engineers G Bazeley B Dennis, MSc D M Rhodes, BSc, AMIEE C Karatsovis, BEng, MSc G J Stimpson, BSc, MSc M C Lower, BSc, MSc, PhD, MIOA A J Varley, BEng, MSc D R Pitcaithley, BA

Assistant Engineer Assistant Engineer M J Parker, BEng J Fithyan, BSc

Research Assistant J Carrilho, MEng

Visiting Industrial Researcher

K Koshimizu, BSc, MSc



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Hearing and Balance Centre (HABC) (at 30.04.02)

Head of Centre

M E Lutman, BSc, MSc, PhD

Research Staff South of England Cochlear Implant Centre (SOECIC)

Audiological Scientists Audiological Scientists J Burgneay, BSc, MSc (Clinical Services Manager) S L Bell, MA, MSc S 1 * A E Morris, BA, MSc 1 * K J Munro, MSc, DMS 1 * E Payne BSc, MSc 1

C A Verschuur, BA, MSc 1 * Research Assistants G Horswell, BA D Rowan, MSc * N Thomas, BEng

J A Eyles, BSc, MSc 1 (Head of Centre) (part-time) S G Cooper, BS, MS, CCC-A (ASHA Cert) H E Cullington, BSc, MSc 1 S L Flynn, BSc, MSc (part-time) M L Grasmeder, BSc, MSc 1 R A Ricaud, MA, MSc 1

Speech & Language Therapists J C Brinton, MSc 4

A Odell, BA(Hons), Postgrad Diploma in Clinical Comm Studies S C Paganga, BSc 4 (part-time) E R Tucker, BSc 4 (part-time)

Teachers of the Deaf S E Cross, BEd, MSc 3

M M Harriott 3

C M Sammons, BEd 3 (part-time)

E J Wood, BSc, MEd 2

ENT Consultants P B Ashcroft, FRCS 5 (part-time) M B Pringle, FRCS 6 (part-time)

Community Physician S Blandy, MB BS, MSc

Medical Officer A T Mooney, BM, MRLGP/DRLDG

1 Certificate of Audiological Competence 2 Certificate of Teacher of the Deaf 3 Certificate in Education of Teacher of Hearing Impaired Children

4 Registered Member, Royal College of Speech and Language Therapists 5 Winchester and Eastleigh Healthcare NHS Trust 6 Portsmouth Hospitals NHS Trust



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Support Staff (at 30.04.02)

Administrative and Clerical

Academic and Departmental Secretary Computer Programmer M Z Strickland G A Jewell

Financial Controller Librarian J Sturgess, BSc, ACA A M Gunn, RSA DipTEFL

Clerical S J Brindle (part-time) M Hookham M Buchan M S Howls (part-time) D J Farrenden A-M McDonnell S J Greenwood M T Page J Griffin (part-time) M A Payne (part-time) E L Gullidge M A Perkins J Halliday J Shotter D M Harris S C Tarling

Technical Staff

Resource Manager Safety Officer J Taylor J Taylor

Electronics & Electrical Services Technicians Laboratory Services Technicians J C Blake (Stores) G C Andrews A R Edgeley D K Edwards, BA J A Haughton, HND (Computer Network Manager) A Sanger G King K Sims R W Stansbridge, BSc D Q A Theobald D V White A Wood

ADAU Technicians Human Factors Research Unit Technicians G Barber C A C J Littler N J Davies, HND G C Parker, HNC, HND P L Oxborrow, BEng H I Philip, BSc, PhD G C J Wells P Russell, BSc

Trainee Technicians New Horizons Trainee (Inter-Departmental Pool) C Beddoe P Wills F B Braga

Industrial Placements R F Cross R Melia


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Research Students * (MPhil/PhD) (at 30.04.02)

Full-time N A A J Abdul Jalil, BEng B E Lobb, BSc, MSc J Alberola, MSc S D Meers, MEng K A Ananthaganeshan, BSc, MSc N S Mohd-Saleh, BEng T D Armstrong, BEng N Nawayseh, BSc, MSc E Baldwin, BEng D Offin, MChem L Benassi, MSc, MIEEE, MAIAA, MIFAC T Papadopoulos, BSc, MSc O Bewes, BEng W-S Park, BSc, MSc P Bonello, BEng, MSc, Eur Ing J Power, BSc C A Butler, BA, MSc F A Price, BSc, MSc A C P R P Carrasco, Licenciado, MSc L E Rees, MSci Y Cho, BEng G Robb, MPhys, MSc I Chun, BSc, MSc E Romero-Vivas, Electronics Engineer, MSc S Colam, BMus, MSc J Rose, BS, MSc M de Castro Magalhaes, BSc, MSc H Salleh, BSc, MSc, EIT H El-Khatib, BEng S Sasananan, BEng, MEng, MSc, PE F Fedele, BEng P A Schmitz, BEng, AmIMechE S Feraday, BEng N A Shusina, BEng, AMIEE A Giani, Dipl Ing P S Tam, BSc, MSc D-S Gong, BSc, MSc M H Tan, BEng M Gutowski, Diplom W K Tseng, BEng, MSc, PhD J M Harte, BEng W Variyart, BSc, MSc N A C Hatcher, BEng K Vivatvakin, BEng, MSc J L Hayes, BSc, AMInstP AUS Y E Watson, BSc V J T Hii, BE J Wilcox, BEng A R Jamaluddin, MEng G Xie, BEng, MSc L Ji, MSc G Yan, BEng, MSc T Johansson, MSc G T Yim, BSc, MSc Y Kim, BSc, MSc J W Yoo, MSc V Kota, BEng, MSc Y Zheng, MSc Y Liu, BEng Q Zhou, BEng, MSc Y Y Liu, BEng, MSc

Part-time (external) P Brandstätt, BSc, MSc D Millar, BEng, MSc E Craney, BEng C Owen, BEng J P dos Santos Nunes, BEng C Öztürk, BSc, MSc H Dumbrell, BA, MA N D Porter, BSc L Gredmaier, BEng S Richards, BSc MPhil ARCS DIC MIOA CPhys MInstP A B Hadlington, BSc C Robertson, BSc A Hall N D Saboori-Khorasani, BSc N Harris, BEng C Skinner, BA, MSci O Inacio, MSc D C Van der Walt, MDipTech E Johnston, BSc, MSc M Veltri H C Martin, BA, MSc D Wallis C Mead, BEng * Excluding Part-time (internal)

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Visiting Students L Andersen, MSc A Deltour N Arndt, Diploma in Educational Science S Guérin, DEA, PhD P Augereau, Diploma of Engineering Mechanics H Illaire, Diplôme d’Ingénieur M P B Bask, MSc M Jones E Bianchi, MEng C Lionnet L Blanchard A Lovstad R Camillacci, MSc S Rossetti, MSc D A Cannizzaro, MEng N Santoro L Carlone, MSc A Stenti, MSc D A Clay S Van Der Hoeven S Clerkson, BEng S Zimmermann, Diplom-Ingenieur

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1. Research

Introductory Remarks Professor P A Nelson

The Institute’s four main Research Groups continue to thrive. The work of the Dynamics Group remains in the broad field of vibrational dynamics, including automotive noise and vibration, railway noise and vibration, rotor dynamics, the vibration of pipes, and smart structures. There is also a particular focus on new methods of numerical analysis and especially the “mid-frequency” range, to which neither finite element nor statistical energy analysis methods are well suited. The laboratory facilities for work in dynamics have been greatly improved and should be a considerable benefit to the experimental activities in this field. Of particular note is the progress being made in Statistical Energy Analysis, force determination by inverse methods and the active control of structures. The topic of railway noise and vibration is being tackled on a number of fronts and the complex dynamics involved will continue to be a challenge for even the most sophisticated analysis techniques that are currently available. The Fluid Dynamics and Acoustics Group has further expanded, with the arrival of seven new members. The main themes of the Group’s work in aeroacoustics and hydroacoustics are well funded and highly productive areas of work. Our relationship with Rolls-Royce is a key factor in the work on aeroacoustics and the collaborative links remain strong, despite the considerable difficulties faced by the company during the past year. The new work on numerical methods has produced useful results on a very short timescale and has been used to great effect in the evaluation of duct liner geometries. Similarly, the application of techniques based on the numerical solution of the linearised Euler equations is showing considerable potential for the solution of complex flow interaction problems. The Hearing and Balance Centre and the Human Factors Research Unit have continued to attract high levels of research funding. It is hoped that research conducted within the Hearing and Balance Centre can be further enhanced by the addition of staff appointments associated with the proposed new undergraduate course in audiology. It is pleasing to note the progress being made on the development and evaluation of new hearing aid technology, particularly with respect to the interaction between these devices and the process of spatial hearing. There is undoubtedly considerable scope for work in this area as technology develops further and the complexities of human hearing become better understood. The work of the Signal Processing and Control Group has expanded successfully to embrace topics in biomedical signal processing, whilst the more established areas of underwater signal processing and active control of sound and vibration remain highly productive themes of work. The potential for interaction with the work of the Hearing and Balance Centre is also being exploited as joint projects between the two groups are initiated. The work on image processing also offers many exciting possibilities, including the exploitation of newly developed methods in the field of biomedical signal processing.

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1.1 Dynamics Group Group Chairman: Dr M J Brennan

Group Developments Although there has been no change in academic staff during the year, there has been a significant change in the Group’s real estate. The old engine test-cell area has been completely refurbished, and in March 2002 we vacated the Building 19 laboratories to move into this new laboratory area. It is split into three laboratories; one is a general purpose area, another is for railway research and will house the wheel-rail rig from Building 19 and the third houses a rotor dynamics rig and two space-frames. This new laboratory space is a first-class facility and should help to ensure that we stay at the forefront of structural dynamics research. A major item of equipment housed in the new laboratory is a scanning laser vibrometer purchased during the year. This was funded by a grant from the EPSRC won by Drs Ferguson and Mace, among others. The offices in Building 19 have also been vacated as the researchers have moved into a suite of offices on the upper floor of the Rayleigh Building. Ms Anne-Marie McDonnell joined the Group in May 2001 as the new Group Secretary. Dr Grice, a long standing member of the Group, left in July 2001 for a position at the University of Portsmouth. Anand Thite has been appointed his successor as the Ford Fellow. Weerachai Variyart and Sheng Xiaozhen have been awarded PhDs and have remained in the Group to work on other projects. Seven new full-time and two part-time research students have joined the Group. This is most satisfactory as it increases the size of the Group in-line with plans. The total number of PhD students is now 20, which is over a fifty-percent increase on last year. Beth Baldwin, a former ISVR undergraduate, is working with Dr Brennan and Dr Ferguson on the high frequency dynamics of tensegrity structures; Gao Yan from China is working with Dr Brennan and Dr Joseph, of the Fluid Dynamics and Acoustics Group, on the characterisation of leak noise; Hanim Salleh from Malaysia is working with Dr Brennan on the use of multiple vibration neutralizers to control waves in beams; Hassan El-Khatib from Kuwait is working with Dr Mace and Dr Brennan on adaptive vibration absorbers to control wave motion in beams; Ji Woo Yoo is working with Drs Thompson and Ferguson on mid/high frequency vibration modelling methods; Paul Schmitz is working with Drs Waters and Thompson on modelling the dynamic behaviour of trucks; Oliver Bewes, the first ISVR EngD student, is working with Drs Jones and Thompson on the design of railway track components to reduce vibration and noise from bridges (in conjunction with Pandrol Rail Fastenings Ltd). A part-time student, Marco Veltri, is working with Dr Ferguson on FE based numerical predictive techniques, for fatigue and accelerated testing. Andrew Monk-Steel has been appointed as a Research Assistant (also a part-time PhD student) working on curve squeal with Dr Thompson.

Group Activities Dr Mace was host to Dr Halkyard from the University of Auckland, New Zealand for 6 months. Together they worked on real-time measurement of wave parameters and active control. They also worked on the measurement of wavenumbers in two-dimensional structures with Dr Ferguson. Dr Thompson was host to Leonardo Carlone from the University of L’Aquila, Italy, who worked on the dynamic coupling between rails and bridges, and Dr Jones hosted Lars Andersen from Aalborg University in Denmark, who worked on three-dimensional boundary elements for elastodynamics as part of his PhD. Graham Brown from the University of New South Wales visited Drs Thompson and Jones in September 2001, working on models for rolling noise of light rail vehicles. Five students have visited the group under the European Doctorate Scheme. Michael Bask from Sweden worked with Dr Mace for one year on active vibration control. Rodolfo Camillacci from Italy has worked for one year on the identification of normal modes and coupled modes in non-linear systems with Dr Ferguson and Dr White of the Signal Processing and Control Group. Andrea Stenti from Italy, working on modelling the dynamics of uncertain structures, is currently visiting Dr Mace. Dr Mace is also hosting Hélène Illaire, a French student, living in Sweden, who is working on active constrained layer damping. Dr Brennan together with Dr Gardonio in the Signal Processing and Control Group are hosting Silvia Rossetti from Italy, who is working on the modelling of rigid-frame porous materials.

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Group members participated in a number of conferences and contributed to a number of short courses during the last year. Dr Wu presented a paper co-authored with Dr Thompson at the 8th International Congress on Sound and Vibration in Hong Kong in July 2001. Philip Bonello also attended this conference and presented two papers co-authored with Dr Brennan. Dr Thompson co-chaired a session at Inter-Noise 2001 in August in The Hague and presented a paper co-authored with Dr Wu. Anand Thite and Max Magalhaes also presented papers at this conference, and Dr Mace co-authored two papers. Drs Thompson, Jones, Wu and Sheng attended the 7th International Workshop on Railway and Tracked Transit System Noise held in Portland, Maine in October 2001. All presented papers and Dr Thompson chaired a session as well as being on the organising committee. Dr Jones also attended NoiseCon 2001 at the same location and presented a paper co-authored with Drs Thompson and Wu. Dr Thompson chaired a session at the IOA Spring Conference in Salford and he, Dr Brennan, Dr Muggleton and Lin Ji presented papers. Dr Brennan and Drs Thompson and Muggleton also presented posters at the EPSRC Theme Day on Acoustics in Salford. As part of an exchange programme with Universidade Estadual Paulista (UNESP) in Brazil, Dr Brennan visited the campus at Ilha Solteira, and has hosted several short visits to the ISVR from members of UNESP (Professors Vicente Lopes Junior, Gilberto Pecheto de Melo, Adyles Arato Junior and Mauro Hugo Mathias). As in the previous five years, Dr Brennan and Dr Ferguson gave short lecture courses at ENSIM (Ecole Nationale Supérieure d'Ingénieurs) at the Université du Maine in Le Mans, France, during the period April to June 2001. Dr Thompson participated in the 8th Savoir course on Railway Noise and Vibration held at Freising/Munich in April 2002. Group members continue to be involved in networking activities. Dr Brennan, Dr Waters, and Tomo Sasananan have attended a number of meetings of the EPSRC-funded network on Structural Integrity and Damage Assessment (SIDANET), and Dr Brennan and Dr Mace have attended meetings of the EU network on smart structures (ASSET). At the last meeting in Giens, a workshop was held and Dr Brennan presented a demonstrator on active vibration isolation. Drs Mace and Ferguson have attended and contributed to the meetings for the EU network on statistical energy analysis (SEANET). Dr Brennan is a member of a new EPSRC-funded network on biomimetics (BIONIS).

Research

Numerical and Analytical Analysis Methods Statistical energy analysis (SEA) is used in both predictive and experimental work to study high frequency transmission in built-up structures. The variability in SEA parameters, in particular coupling loss factors, have been examined through the use of the dynamic stiffness method (DSM) and wave transmission models of coupled-rectangular plates. This has highlighted the effect of both source and receiver characteristics on vibration transmission. Confidence intervals for the coupling loss factor, a key parameter in SEA, have been established and some rules of thumb involving modal overlap and number of modes in a frequency band have been determined. Research is continuing into the so-called ‘mid-frequency’ range, which is above the range where finite element (FE) analysis gives reliable results, and below the range where SEA can be used with confidence. Here, structural variability and uncertainty cause difficulties, and new numerical approaches to vibration modelling and prediction are required. A number of projects concern vibration modelling of long wavelength/low modal density subsystems coupled to short wavelength/high modal density subsystems. In such cases the size of the whole system is too large for a full FE model, while SEA cannot accurately predict the response of the long wavelength subsystem. A power mode approach has been developed which gives bounds for the coupling power, together with an estimate of the frequency-average power. This has been developed for multiple sources and extended to the case of source/receiver subsystems with a significant impedance mismatch. A wave approach to this problem is also being developed. Component mode methods are being applied to the case of built-up structures where there is uncertainty in the properties of the joints. Energy flow and SEA models have been developed in terms of modal behaviour. Conditions for the existence of a proper SEA model have been determined, and expressions for the parameters of such a model (direct and, if required, indirect coupling loss factors) have been found.

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A component mode synthesis (CMS) method has been developed to model noise transmission through a flexible partition between two rooms. The model is currently a one-dimensional model but is being extended to three dimensions. Improvement in the estimation of the performance of lightweight partitions have been achieved. The DSM has been applied to the determination of the acoustically induced response of aerospace structures modelled as plain and stiffened panels. Predictions based on the DSM method have been validated against other numerical (FE) and benchmark analytical results. The work is being extended to produce dynamic stiffness matrices for curved honeycomb sandwich panels and the models will be validated against experimental data that has already been acquired from progressive wave tunnel tests.

Automotive Noise and Vibration Inverse force determination has wide application in the field of transfer path analysis. Research has been carried out into the use of matrix regularisation techniques to improve the condition of the matrix that is inverted. This study has been extended to consider techniques for the selection of transducer locations. It has been shown that by identifying a ‘good’ set of response locations from frequency response measurements, the matrix condition can be controlled without the need for matrix regularisation or excessive over-determination. Studies of noise from engine covers have continued with the development of a dynamic stiffness model of a valve cover and gasket assembly, for the prediction of the vibration isolation. Further measurements of radiation efficiency and of airborne sound transmission through valve covers have also been carried out. Work has continued on the modelling of tyre vibration in two separate projects, one sponsored by the EU (RATIN) and one in conjunction with a Korean tyre company. Two models have been developed using alternative wave approaches that overcome the high frequency limitations of finite element models. The models are valid over the entire frequency range of concern for interior and exterior automobile noise. Effects of rotation, which causes stiffening of the tyre, in-plane tension and the orthotropy of the tyre are accounted for. The models have now been validated by way of mobility measurements and it is planned to use the models to study the interaction of a tyre rolling on a rough surface. A new project has started in conjunction with Transport Research Laboratories (TRL) on predicting noise and vibration in truck cabs. A dynamic stiffness approach will be used to model a flexible chassis connected to lumped parameter representations of the suspension and cab.

Railway Noise and Vibration Within the EPSRC-funded project on non-linear wheel/rail contact a considerable number of experimental results have been obtained from the one-fifth scale wheel/rail rolling rig for rails with various different features on the running surface. Processing of this data is continuing and the results are being compared with both linear and non-linear theoretical models. The modelling work has been extended to include the response to rail joints, the effects of coupling between vertical and lateral directions and a model of roughness growth. A project on curve squeal has commenced during the year. In the EU-funded project STAIRRS, theoretical work has been carried out to assist in the development by other partners of new measurement methods. An assessment has been carried out using theoretical models of the likely differences between measurement results at different locations due to parameters such as ground properties, temperature, wheel load, wear and manufacturing tolerances. A new EPSRC-funded project on ground vibration from trains in tunnels has commenced. Analytical and numerical models, which build on previous analytical models of vibration from surface trains, are being developed for tunnel structures in a layered ground. These models use wavenumber boundary element techniques to give results for three-dimensional propagating waves from moving loads. They take advantage of the two-dimensional geometry that is uniform in the direction along the tunnel to gain computational efficiency. One approach being developed couples a wavenumber finite element model for the tunnel structure with a wavenumber boundary element model of the ground. Another approach uses analytical models for a tube connected to a layered ground. A fully three-dimensional combined finite element/boundary element model for ground vibration has also been produced in collaboration with Aalborg University. This is a general model for elastodynamics in infinite solids and uses an extension of the method developed for two dimensions in an earlier EPSRC project.

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Research on railway vehicle interior noise has concentrated on modelling the modal density and acoustic radiation of extruded aluminium panels. At low frequencies these behave as orthotropic plates, but above about 500 Hz local modes of the various strips of the structure occur and the modal density increases considerably. It has also been shown that the usual approximate estimates of radiation efficiency of plates are unreliable for plates with a large aspect ratio, such as those used to represent the strips of the extruded aluminium panels. Measurements of vehicle interior noise were also carried out on an ex-BR Mark2 coach at the Mid-Hants Railway at Alresford. Work on railway bridges has continued with an investigation of the coupling between two beams connected by a series of discrete springs. Random variations in the stiffness or spacing of these springs lead to an increase in the power transmitted to the bridge from the track. A detailed investigation into the input mobility of a deep I-section beam has also been carried out to determine the parameters that affect the increase in mobility at high frequencies where compressional effects are significant.

Porous Materials Work has continued on the modelling of the acoustic behaviour of rigid-frame porous materials. The aim of this work is to determine, from knowledge only of geometry, the wavenumber and characteristic impedance of a material made from regular granules.

Rotor Dynamics In collaboration with Professor Roy Holmes of the School of Engineering Sciences, rotor dynamics research has continued to make significant progress. An approach to modelling highly non-linear squeeze-film bearings on a super-critical rotor developed earlier has been validated experimentally on three different rotor configurations. The technique uses the harmonic balance method at speeds where the rotor experiences periodic vibration, and a time-domain method when the rotor vibration is quasi-periodic or chaotic. The method is computationally efficient, and can use measured frequency response functions or predicted frequency response functions in conjunction with a non-linear model of the squeeze-film. A new project has started on the dynamics of a turbocharger. These devices rotate at extremely high speeds ranging from 150,000 rpm to 200,000 rpm. They tend to vibrate in a limit cycle at frequencies well below the rotational speed, and this vibration can cause undesirable noise. A simple single-degree-of-freedom linear model has been developed to predict the frequency at which the self-excited vibration occurs and this is being extended to a two-degree-of-freedom model. Experimental work to validate the models is being undertaken in a facility owned by the School of Engineering Sciences.

Pipe Vibration In the EPSRC-funded project on detecting water leaks and locating buried plastic pipes, a model of a buried water-filled plastic pipe has been validated on a test-site at the University of East Anglia. Preliminary experiments have also been carried out on this site to investigate which parameters can be used to detect a buried pipe from vibration measurements. In a separate project, simplified dispersion relation and expressions for point and transfer mobilities have been determined for in-vacuo pipes. These relationships have been validated by experimental work in the laboratory.

Smart Structures and Active Vibration Control The EPSRC-funded project on the active isolation of equipment (in collaboration with Professor Elliott in the Signal Processing and Control Group) is in its final year. The thrust of the research is to investigate the effectiveness and limitations of simple control strategies. Simple rules of thumb have been determined to give the maximum gain that can be applied to the system in terms of the characteristics of the instrumentation in the control loop. A multi-channel demonstrator has been built and presented to a workshop on smart structures: a patent has been applied for. Work on the active control of beam vibrations using feedback control is in progress. Rather than using complex control laws, the approach adopted has been to use simple analogue control, choosing the actuator-sensor pairs that give the best performance. It has been shown that while a force-accelerometer is the best theoretical combination, the best practical combination is a piezoceramic element and an accelerometer pair.

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Equipment

Controller

Base plate

A project has commenced concerning the adaptive-passive control of structureborne vibrations using self-tuning vibration absorbers and real-time wave estimates. An approach to active vibration isolation using external model control has been investigated. Work has also commenced concerning control laws for active constrained layer damping treatments. Work is continuing on a project concerning the use of semi-active control for vibration and shock isolation. Control algorithms have been compared though simulations and a rig is currently being developed to implement semi-actively controlled electromechanical damping.

Dynamic Modelling Experimental measurements of the response of flat, curved, isotropic and orthotropic panels having been made using the new scanning laser vibrometer, and methods for processing these measurements to estimate wavenumbers have been investigated. The resulting information is of value for noise and vibration prediction and SEA modelling. Techniques for estimating wave amplitudes in real-time have also been developed for the case of bending vibrations in the presence of near-field waves. These have been applied to the measurement of structural intensity and as a cost function for active vibration control. A project concerning damage detection using vibration data has focused on the development of techniques to investigate the sensitivity to changes in boundary conditions. The ultimate aim is to develop a simple technique to detect the integrity of the foundation of a lighting column. The parameter, which in principle is relatively easy to measure and is quite sensitive to foundation stiffness, is the static stiffness measured at some point on the column. The challenge is to develop a robust way of measuring this using an impact hammer. A project has commenced on modelling the dynamic characteristics of tensegrity structures. As the name suggests, these structures consist of elements that can statically either support tensile forces or compression forces. So far the project has focused on the wave filtering properties of joints in a tensegrity structure.

Active Vibration Isolation Demonstrator Acoustic measurements in a railway carriage

List of Research Projects

1.1 Numerical and Analytical Analysis Methods 1.1.1 A power mode approach to the estimation of vibrational power transmission from multiple sources

(L Ji, R J Pinnington, B R Mace) 1.1.2 Power transmission between long and short wavelength substructures using a power mode technique

(L Ji, R J Pinnington, B R Mace) 1.1.3 The response of built-up structures with joint uncertainties (A Stenti; P Sas [Department of

Mechanical Engineering, Katholieke Universiteit, Leuven]; B R Mace) 1.1.4 Energy flow and SEA models from system modes (B R Mace) 1.1.5 Direct and indirect coupling loss factors and strong coupling in SEA (B R Mace)

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1.1.6 Wave models and energy flow in irregular and regular structures (E C N Wester [Industrial Research Ltd]; B R Mace)

1.1.7 Spectral finite elements (N S Ferguson) 1.1.8 FE based modelling for acoustic fatigue (N S Ferguson) 1.1.9 Development of the component modes synthesis method for structural acoustic problems in buildings

(M de Castro Magalhaes, N S Ferguson) 1.1.10 Confidence intervals for statistical energy analysis parameters (W-S Park, D J Thompson,

N S Ferguson) 1.1.11 A practical hybrid method for mid-frequency vibration analysis of built-up structures (J W Yoo,

N S Ferguson , D J Thompson) 1.1.12 FE based techniques for vibration fatigue and accelerated testing (M Veltri, N S Ferguson) 1.1.13 The application of the dynamic stiffness method in determining the response of aerospace structures to

acoustic excitation (D Millar, N S Ferguson)

1.2 Automotive Noise and Vibration 1.2.1 Sound radiation from engines (R M Grice, D J Thompson, A Thite; C Lim [Hyundai, Korea]) 1.2.2 Inverse determination of structure-borne sound sources (A Thite, D J Thompson) 1.2.3 Tyre noise and vibration (R J Pinnington, J M Muggleton, B R Mace, M J Brennan) 1.2.4 Modelling of brake squeal (M J Brennan; K Shin [Hanyang University]; C J Harris [Department of

Electronics and Computer Science]) 1.2.5 Modelling of truck cabs (P A Schmitz, T P Waters, D J Thompson)

1.3 Railway Noise and Vibration 1.3.1 Models for groundborne vibration from trains (X Sheng, C J C Jones, D J Thompson) 1.3.2 Non-linear effects at the wheel/rail interface and their influence on noise generation (D J Thompson,

J K Hammond, T X Wu, T D Armstrong) 1.3.3 STAIRRS – Strategies and Tools to Assess and Implement Noise Reducing Measures for Railway

Systems (D J Thompson, C J C Jones) 1.3.4 Modelling of curve squeal noise (D J Thompson, T P Waters, A Monk-Steel) 1.3.5 Modelling of a rail coupled to a bridge (D J Thompson, L Carlone) 1.3.6 A modelling approach for the interior noise of railway vehicles (G Xie, D J Thompson, C J C Jones) 1.3.7 Calculation of noise from elevated railway structures (O Bewes, C J C Jones, D J Thompson) 1.3.8 Ground vibration and noise from trains in tunnels (X Sheng, C J C Jones, D J Thompson) 1.3.9 A three-dimensional coupled boundary element/finite element model for elastodynamics (L Andersen,

C J C Jones)

1.4 Porous Materials 1.4.1 Characterising the acoustic properties of rigid-frame porous materials (S Rossetti, M J Brennan,

P Gardonio)

1.5 Rotor Dynamics 1.5.1 Squeeze-film dampers in rotor systems (P Bonello, M J Brennan; R Holmes [Mechanical

Engineering]) 1.5.2 High frequency behaviour of rotating beams (M J Brennan) 1.5.3 Condition monitoring of gear vibration (M J Brennan; D Forrester [DSTO, Australia])

1.6 Pipe Vibration 1.6.1 Detection of leaks in buried water-filled pipes (J M Muggleton, M J Brennan) 1.6.2 Modelling the dynamics of pipes (W Variyart, M J Brennan) 1.6.3 Development of wave models for mass flow meters (J M Muggleton, T P Waters) 1.6.4 Characterisation of leak-noise in buried pipes (G Yan, M J Brennan, P F Joseph, J M Muggleton)

1.7 Smart Structures and Active Vibration Control 1.7.1 Adaptive vibration absorbers (M J Brennan) 1.7.2 Active vibration neutralisers (M J Brennan; F de Plooy, S Heyns [University of Pretoria]) 1.7.3 Active vibration isolation (K Ananthaganeshan, M J Brennan, S J Elliott)

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1.7.4 Active control of waves in fluid-filled pipes (W Variyart, M J Brennan) 1.7.5 Semi-active shock and vibration isolation (Y Liu, B R Mace, T P Waters) 1.7.6 Adaptive-passive control of structure-borne vibrations (H El-Khatib, M J Brennan, B R Mace) 1.7.7 Active vibration control of bending waves in the presence of nearfields (B R Mace; C R Halkyard

[University of Auckland, New Zealand]) 1.7.8 Variable stiffness elements for adaptive vibration control devices (M J Brennan, S J Elliott;

G Jeronimidis [University of Reading]; J F V Vincent [Bath University]) 1.7.9 External model control of vibrations (M P B Bask; A Medvedev [Control Engineering Group, Lulea

University of Technology]; B R Mace) 1.7.10 Active constrained layer damping (H Illaire; W Kropp [Department of Applied Acoustics, Chalmers

University, Gothenburg; B R Mace)

1.8 Dynamic Modelling 1.8.1 Modelling the flight motor of an insect (M J Brennan, S J Elliott, P Bonello) 1.8.2 Damage detection using vibration analysis (S Sasananan, M J Brennan, T P Waters) 1.8.3 Dynamic modelling of tensegrity structures (E Baldwin, N S Ferguson, M J Brennan) 1.8.4 Control of bending waves on beams using multiple vibration neutralizers (H Salleh, M J Brennan) 1.8.5 Experimental estimation of wavenumbers in two-dimensional structures (C R Halkyard [University of

Auckland, New Zealand]; N S Ferguson, B R Mace) 1.8.6 Real-time measurement of bending wave amplitudes in the presence of a nearfield (C R Halkyard

[University of Auckland, New Zealand]; H El-Khatib, B R Mace) 1.8.7 The identification of non-linear normal modes and coupled non-linear modes (R Camillacci,

N S Ferguson, P R White) 1.8.8 Validation of radiation efficiency formulae for spatially orthotropic panels (N S Ferguson;

P R Cunningham [School of Engineering Sciences]; J Anderson [ESDU International Plc])

Publications Ananthaganeshan, K.A., Brennan, M.J. and Elliott, S.J. Low and high frequency instabilities in feedback control of a vibrating single degree of freedom system, ISVR Technical Memorandum 870, Southampton, University of Southampton, 2001, 110pp. Andersen, L. and Jones, C.J.C. Three-dimensional elastodynamic analysis using multiple boundary element domains, ISVR Technical Memorandum 867, Southampton, University of Southampton, 2001, 47pp. BEASTS – A computer program for boundary element analysis of soil and three-dimensional structures, ISVR Technical Memorandum 868, Southampton, University of Southampton, 2001, 38pp. Bonello, P. and Brennan, M.J. Modelling of the dynamic behaviour of a super critical rotor on a flexible foundation using the mechanical impedance technique. Journal of Sound and Vibration, 239(3), 2001, 445-66. Bonello, P., Brennan, M.J. and *Holmes, R. Harmonic balance analysis of squeeze film damped rotor dynamic systems using receptances. Proceedings of the 8th International Congress on Sound and Vibration, Hong Kong, China, 2-6 July 2001, 2027-34. On the dynamics of unsupported squeeze film damper bearings. Proceedings of the 8th International Congress on Sound and Vibration, Hong Kong, China, 2-6 July 2001, 1099-116. Brennan, M.J. and *Dayou, J. Global control of vibration using a tunable vibration neutraliser. Noise and Vibration Worldwide, 32(5), 2001, 16-23. Brennan, M.J. and *Kim, S.-M. Feedforward and feedback control of sound and vibration – A Wiener filter approach. Journal of Sound and Vibration, 246(2), 2001, 281-96. Brennan, M.J. and *To, W.M. Acoustic properties of rigid-frame porous materials – An engineering perspective. Applied Acoustics, 6, 2001, 793-811.

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Brennan, M.J., Elliott, S.J., Bonello, P. and *Vincent, J.F.V. Investigation into a suitable flight motor for micro air vehicles. Poster Presented at Conference on Micro-Robotics: Can Technology Outsmart Nature?, Institute of Materials, London, UK, 16 May 2001. *Dayou, J. and Brennan, M.J. Optimum tuning of a vibration neutralizer for global vibration control. Proceedings of the Institute of Mechanical Engineers, 215(C), 2001, 933-42. *Kidner, M.R.F. and Brennan, M.J. Real-time control of both stiffness and damping in an active vibration neutralizer. Institute of Physics Publishing – Smart Materials and Structures, 10, 2001, 758-69. *Kim, S.-M., Elliott, S.J. and Brennan, M.J. Decentralised control for multi-channel active vibration isolation. IEEE Transactions on Control Systems Technology, Special Issue on Dynamics and Control of Smart Structures, 9(1), 2001, 93-100. *Siew, C.C., *Hill, M., *Holmes, R. and Brennan, M.J. A theoretical and experimental investigation into the vibration response of a flexible rotor and squeeze film damper system. Proceedings of the Institution of Mechanical Engineers, Journal of Mechanical Engineering Science, 215(C), 2001, 1251-69. Carlone, L. and Thompson, D.J. Vibrations of a rail coupled to a foundation beam through a series of discrete elastic supports, ISVR Technical Memorandum 873, Southampton, University of Southampton, 2001, 72pp. de Castro Magalhaes, M.D.C. and Ferguson, N.S. Low frequency airborne sound transmission in buildings: Modal Analysis, ISVR Technical Memorandum 864, Southampton, University of Southampton, 2001, 32pp. Ferguson, N.S. and Jewell, G.A. The development and use of a noise control materials database. Proceedings of the 4th European Conference on Noise Control, EURONOISE 2001, Patras, Greece, 14-17 January 2001, 10pp. Ferguson, N.S., Park, W.S. and Thompson, D.J. The sources of variability within SEA coupling loss factor estimation. Proceedings of the 4th European Conference on Noise Control, EURONOISE 2001, Patras, Greece, 14-17 January 2001, 12pp. *Birgersson, F., Ferguson, N.S. and *Finnveden, S. Spectral FE prediction of the vibration response of structures excited by turbulent boundary layer flow. Proceedings of the 8th International Congress on Sound and Vibration, Hong Kong, China, 2-6 July 2001, 1381-8. *Finnveden, S., *Birgersson, F. and Ferguson, N.S. Modelling with the spectral FEM for turbulence excitation of cylindrical pipes. Proceedings of Inter-Noise 2001, The Hague, The Netherlands, 5, 27-30 August 2001, 2497-502. Grice, R.M. and Pinnington, R.J. Analysis of the flexural vibration of a thin-plate box using a combination of finite element analysis and analytical impedances. Journal of Sound and Vibration, 249(3), 2001, 499-527. Ji, L., Mace, B.R. and Pinnington, R.J. Power transmission between long-wavelength sources and short-wavelength receivers, ISVR Technical Memorandum 876, Southampton, University of Southampton, 2001, 75pp. Power transmission to flexible receivers by force sources, ISVR Technical Memorandum 877, Southampton, University of Southampton, 2001, 37pp. Jones, C.J.C. Review of Wu, T. Boundary element acoustics: Fundamentals and computer codes. In: Journal of Sound and Vibration, 240(5), 2001, 974-8. Jones, C.J.C. and Thompson, D.J. Means of controlling rolling noise at source. In Krylov, V.V. ed. Noise and Vibration from High-Speed Trains, London, Thomas Telford, 2001, 163-83.

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Extended validation of a theoretical model for railway rolling noise using novel wheel and track designs. Proceedings of the 7th International Workshop on Railway and Tracked Transit System Noise, Portland Maine, USA, 2001, 10pp. Jones, C.J.C., Thompson, D.J. and Waters, T.P. The application of numerical models to a system of train- and track-mounted acoustic shields. International Journal of Sound and Vibration, 6(4), 2001, 185-92. Jones, C.J.C., Thompson, D.J. and Wu, T.X. Developments in the modelling of wheel-rail rolling noise. Proceedings of NoiseCon 2001, Portland Maine, USA, 2001, CD ROM. Mace, B.R. Energy flow models, S.E.A. model and system modes. Proceedings of the 4th European Conference on Noise Control, EURONOISE 2001, Patras, Greece, 14-17 January 2001, 1-16. Mace, B.R. and *Shorter, P.J. A local modal/perturbational method for estimating frequency response statistics of built-up structures with uncertain properties. Journal of Sound and Vibration, 242(5), 2001, 793-811. Mace, B.R., *Jones, R.W. and *Harland, N.R. Wave transmission through structural inserts. Acoustical Society of America, 109(4), 2001, 1417-21. *Halkyard, C.R. and Mace, B.R. Real-time estimation of flexural wave amplitude in a beam in the presence of a nearfield. Proceedings of Inter-Noise 2001, The Hague, The Netherlands, 2, 27-30 August 2001, 875-8. Adaptive control of flexible vibration in the presence of a nearfield. Proceedings of Inter-Noise 2001, The Hague, The Netherlands, 2, 27-30 August 2001, 879-82. *Harland, N.R., Mace, B.R. and *Jones, R.W. Wave propagation, reflection and transmission in tunable fluid-filled beams. Journal of Sound and Vibration, 241(5), 2001, 735-54. Adaptive-passive control of vibration transmission in beams using electro/magnetorheological fluid filled inserts. IEEE Transactions on Control Systems Technology, 9(2), 2001, 209-20. *Mei, C., Mace, B.R. and *Jones, J.W. Hybrid wave/mode active vibration control. Journal of Sound and Vibration, 247(5), 2001, 765-84. *Wester, E.C.N. and Mace, B.R. Statistical measures of energy flow in complex systems using a wave-based approach. The 2001 International Congress and Exhibition on Noise Control Engineering, 2001, 4. Magalhaes, M.D.C. and Ferguson, N.S. Low frequency airborne sound transmission. The 2001 International Congress and Exhibition on Noise Control Engineering, The Hague, The Netherlands, 3, 27-30 August 2001, 1111-4. Muggleton, J.M., Brennan, M.J. and Pinnington, R.J. Development of a water pipe monitoring system for leak detection: Experimental Work, ISVR Technical Memorandum 860, Southampton, University of Southampton, 2001, 29pp. Muggleton, J.M., *Kondracki, M. and Allen, R. Spinal fusion for lumbar instability – does it have a scientific basis? Journal of Spinal Disorders, 13(3), 2001, 200-4. Park, W.S., Thompson, D.J. and Ferguson, N.S. The influence of the source and receiver modal behaviour on power transmission between two subsystems, ISVR Technical Memorandum 861, Southampton, University of Southampton, 2001, 42pp. An empirical model for the variability of the coupling loss factor, ISVR Technical Memorandum 874, Southampton, University of Southampton, 2001, 47pp.

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Petyt, M. Review of Hayek, S.I. and Dekker, M. Advanced mathematical methods in science and engineering. In: Journal of Sound and Vibration, 248(5), 2001, 975-6. European Editor, Journal of Sound and Vibration, Academic Press, published weekly commencing with 239(1), 2001. Sheng, X., Jones, C.J.C. and Thompson, D.J. A comparison of a theoretical model for vibration from trains with measurements. Proceedings of the 7th International Workshop on Railway and Tracked Transit System Noise, Portland Maine, USA, 2001, 10pp. A comparison of a theoretical model for quasi-statically and dynamically induced environmental vibration from trains with measurements, ISVR Technical Memorandum 865, Southampton, University of Southampton, 2001, 42pp. TGV – A computer program for train-induced ground vibration, ISVR Technical Memorandum 878, Southampton, University of Southampton, 2001, 30pp. Thite, A.N. and Thompson, D.J. Use of regularization techniques to identify structure-borne noise sources. Proceedings of Inter-Noise 2001, The Hague, The Netherlands, 2, 27-30 August 2001, 903-6. Experimental validation of force identification techniques, ISVR Technical Memorandum 862, Southampton, University of Southampton, 2001, 108pp. Thompson, D.J. The influence of the contract zone on the excitation of wheel/rail noise. Proceedings of the 7th International Workshop on Railway and Tracked Transit System Noise, Portland Maine, USA, 2001, 11pp. Theory of generation of wheel/rail rolling noise. In: Krylov, V.V. ed. Chapter 1 of Noise and Vibration from High-Speed Trains, London, Thomas Telford, 2001, 3-26. Thompson, D.J. and Wu, T.X. The effects of non-linearities at the wheel/rail interface on the generation of rolling noise. Proceedings of Inter-Noise 2001, The Hague, The Netherlands, 1, 27-30 August 2001, 129-34. *Geerlings, A.C., Thompson, D.J. and *Verheij, J.W. Model-based acoustical substitution source methods for assessing shielding measures applied to trains. Applied Acoustics, 62(8), 2001, 979-1000. *Lee, J. and Thompson, D.J. Dynamic stiffness formulation, free vibration and wave motion of helical springs. Journal of Sound and Vibration, 239(2), 2001, 297-320. *Talotte, C., *Gautier, P.E., Thompson, D.J. and *Hanson, C. Identification, modelling and reduction potential of railway noise sources: A critical survey. Proceedings of the 7th International Workshop on Railway and Tracked Transit System Noise, Portland Maine, USA, 2001, 22pp. Wu, T.X. and Brennan, M.J. Authors reply to comments on the Stability analysis of pantograph-catenary system dynamics, Guan, Y.H. and Lim, T.C. Journal of Sound and Vibration, 247(2), 2001, 535-6. Wu, T.X. and Thompson, D.J. A hybrid model for wheel/track dynamic interaction and noise generation due to wheel flats, ISVR Technical Memorandum 859, Southampton, University of Southampton, 2001, 42pp. On the impact noise generation due to a wheel passing over rail joints, ISVR Technical Memorandum 863, Southampton, University of Southampton, 2001, 34pp. The effects on railway rolling noise of wave reflections in the rail and support stiffening due to the presence of multiple wheels. Applied Acoustics, 62(11), 2001, 1249-66. A model for impact forces and noise generation due to wheel and rail discontinuities. Proceedings of the 8th International Congress on Sound and Vibration, Hong Kong, China, 2-6 July 2001, 2905-12.

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Vibration analysis of railway track with multiple wheels on the rail. Journal of Sound and Vibration, 239(2), 2001, 69-97. On the impact noise generation due to a wheel passing over rail joints. Proceedings of the 7th International Workshop on Railway and Tracked Transit System Noise, Portland Maine, USA, 2001, 11pp. * - Not working in ISVR

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1.2 Fluid Dynamics and Acoustics Group Group Chairman: Professor C L Morfey

Group Developments The group continues to grow with the arrival of seven new members in the last year. Dr Gary Heald of QinetiQ, Winfrith has been appointed to a Visiting Senior Lectureship. Dr Matthew Wright has been awarded a five-year Advanced Research Fellowship by EPSRC. The current year has marked the second full year of operation of the Rolls-Royce University Technology Centre (UTC) in Gas Turbine Noise, and has seen Dr Andrew Kempton take over as UTC co-ordinator at Rolls-Royce. We acknowledge the important contribution that his predecessor, Dr Brian Tester, has made to the successful operation of the UTC. Dr Tester will continue to act as co-ordinator of the Turbonoise CFD project (see below) from his new base in ISVR. The UTC is based within the Fluid Dynamics and Acoustics Group and supports in whole or in part the activities of 18 staff and researchers. It has been a year of growth and consolidation but also a year of some anxiety as the aircraft and aero-engine industries were thrown into crisis following the events of September 11th. Fortunately, the UTC operates on a longer term budgetary timescale (a rolling five-year plan) and has been largely insulated from the well-publicised shorter term funding constraints which have taken place elsewhere within Rolls-Royce. The past year has coincidentally seen important changes in the way that the UTC is funded, as the Department of Trade and Industry has taken direct responsibility for providing a portion of UTC funds – matched by Rolls-Royce contributions – for the next three years. Longer-term projects should benefit in terms of additional stability and continuity. Professor Leighton and his co-investigators Dr White and Professor Astley have won nearly £130K in a contract from QinetiQ to research ‘Very high frequency acoustic scattering for MCM classification modelling’, in conjunction with Dr Dix of the Southampton Oceanography Centre. The A B Wood tank has been refitted, with an anechoic region suitable for use with the high frequency narrow beams employed in the above sediment acoustics project.

Group Activities The group was well represented at the Institute of Acoustics Spring Conference 2002, held in March at the University of Salford: eight papers were presented or co-authored by group members, while Professor Nelson gave a keynote address and organised a special session on “Hot Topics in Acoustics”. The latter included contributions from Professor Astley on computational acoustics in flows, and Dr Wright on semiclassical methods applied to acoustics. A novel feature which contributed to the success of the meeting was the involvement of EPSRC, who worked with the Institute of Acoustics to organise the first-ever Theme Day on Acoustics as an integral part of the programme: this took the form of poster presentations by a representative selection of current or recently-completed grant holders. Assessors for EPSRC – one of whom was Dr Fisher – questioned each researcher and reported back to the research council, providing a “snapshot” of the current state of acoustics research in UK universities. The EPSRC Theme Day was organised jointly by EPSRC and the Institute of Acoustics Research Co-ordination Committee, which includes Professors T G Leighton and M E Lutman, and is chaired by Professor K Attenborough of the University of Hull. Professor Leighton has been awarded the 2002 Tyndall Medal of the Institute of Acoustics for his work on ultrasonics and cavitation. He also travelled to Fort Lauderdale in December 2001 to receive the International Medwin Prize for Acoustical Oceanography from the Acoustical Society of America, at their 142nd meeting (see last year’s report); and in the same month presented a keynote address to the Inaugural Joint Meeting of the Institute of Physics and Anglo-French Physical Acoustics Group Conference in Kent (organised by the Physical Acoustics Group of the Institute of Physics and Société Française d’Acoustique). Professor Davies attended the 17th ICA Conference in Rome, September 2001, where he presented a paper co-authored by K R Holland and D C Van der Walt, “The measurement and control of flow generated noise”. Dr Joseph gave an invited talk on flow duct acoustics at the Twentieth Anniversary Meeting of the Acoustical Society of Korea.

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Research

Aeroacoustics and Non-linear Acoustics

(i) Airframe Noise The RAIN project on the reduction of airframe noise generated by aircraft landing gears and high lift devices has been completed. In this study ISVR have mainly focused on modelling the noise of landing gears and predicting the effect of partial fairings. The work is now being continued under the framework of the SILENCE(R) project, with ISVR acting as aeroacoustic advisers to the airframe industry for the design of flightworthy noise control devices and also developing models of the aeroacoustic interaction between landing gears and flaps. Useful steps forward have been made in the modelling of noise mechanisms in high lift slats and flaps, with cross-fertilisation of ideas between a study in ISVR Consultancy Services and a joint ISVR/School of Engineering Sciences research project. This collaboration has led to the submission of a number of new research funding proposals for the use of CAA methods in both landing gear and HLD problems.

(ii) Jet Mixing Noise Jet noise research is currently supported under the auspices of three EPSRC grants with further support from the EU programme JEAN. The first of these EPSRC programmes represents a follow-on to the successful modelling of sound sources in turbulent channel flow at low Mach numbers. The approach used in the channel flow study will be extended to free shear layers, specifically to a plane turbulent jet. The Lighthill acoustic analogy is used to identify different source mechanisms. New features in the follow-on study are the presence of density gradients in the flow, and the inclusion of scattering by sharp edges. The second EPSRC programme is being conducted in co-operation with Loughborough University. The objective is to use RANS CFD calculations as input to appropriate aerodynamic noise models for jet noise prediction. The aerodynamic noise modelling work carried out at ISVR has clearly identified those parameters in the turbulent flow field which must be calculated (or estimated) from the RANS calculations in order to obtain an unambiguous noise prediction. Good agreement with measured far-field spectra and axial source strength distributions has been obtained for single stream jets. The objective of the third EPSRC programme is to develop a prediction method for the near-field pressures (and hence fatigue loads) created by coaxial jet flows. The work divides logically into two parts. First, as reported in the previous Annual Report, an extensive database of source location data for coaxial jets was acquired from the NTF at Pyestock. This data has now been analysed using improved algorithms developed during the past year. The second portion of the work involves the extension of the ‘Four Source Model’, originally developed at ISVR for prediction of the far-field noise of coaxial jets, to near-field prediction. Progress during the year includes an extensive comparison of an improved version of this model with the new far-field data acquired at Pyestock (see above) and development of the software needed to extend the method to near-field prediction. The final component of the jet noise programme, principally supported by JEAN, is to revisit the complex question of jet noise directivity. Based on numerical solutions of the Lilley equation, our objective is to extend existing far-field prediction methods to arbitrary source distributions and arbitrary frequency, particularly within the “cone of silence”. Low frequency and high frequency analytic solutions are being compared with the full numerical solution, both inside and outside the cone of silence region.

(iii) Aircraft Engine Turbomachinery Noise

RESOUND The EU programme RESOUND was extended to June 2001 in order to permit proper assessment of the fan noise measurements obtained by Rolls-Royce during the project. The ISVR contribution involved the assessment of buzz-saw noise from supersonic tip speed fans, and comparison of measurements with predictions of the ISVR “FDNS” (Frequency Domain Numerical Solution) computer code. Measurements of the modal content of the sound field have led to a much improved understanding of the limitations of the FDNS code for buzz-saw noise prediction. This work is now continuing under the SILENCE(R) project.

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SILENCE(R) The UTC has been involved this year in evaluating a finite/infinite element code, ACTRAN, on behalf of Rolls-Royce for application to turbofan propagation problems. The ACTRAN benchmark tests were successfully completed in June 2001; this has involved the development of a mode-matching code to calculate scattering at a rigid/lined interface in a circular duct containing a uniform mean flow. Full membership of the ACTRAN users consortium was confirmed later in the year. This code has since proved invaluable as a tool for assessing various novel liner concepts – zero splice liners and extended lip liners in particular – within the SILENCE(R) project. Comparisons between ray-theory code predictions (SAINT) and ACTRAN mode-based analyses have been run, to assess their suitability for propagation of broadband fan noise, through the inlet duct and into the far-field. Preliminary results indicate that an overlap exists between the two methods in the mid-frequency range. Fully three-dimensional propagation problems still present major practical difficulties in terms of the computational effort that they require. Long-term strategies to deal with such problems have been initiated within the current year. These include continuing work on time-domain Finite Element models and low dispersion CAA codes based on a linearised Euler approach. In particular, significant progress has been made in applying high-order linearised Euler codes to sound radiation from aircraft engine inlets and exhausts. A compact finite-difference scheme is combined with sponge layers to eliminate reflections from the domain boundary. The code has been successfully benchmarked against analytical predictions for a simplified inlet geometry.

Turbonoise CFD During the last 12 months, code development for prediction of fan and turbine noise propagation to the far-field has been completed. The numerical method uses a linearised Euler equation and a Ffowcs Williams-Hawkings acoustic analogy. The two-dimensional linearised Euler equation has been adapted to deal with single spinning mode propagation without extra memory penalty. The results of an unflanged duct test showed good agreement with numerical predictions based upon a finite element code results (near-field) and analytical solutions (far-field). Numerical results were presented at the IMA Conference, Greenwich, April 2002 and submitted as an AIAA paper.

Broadband Fan Noise A model has been developed to allow predictions of the broadband noise spectrum due to interaction between the turbulent wake from a rotor and downstream stator vanes. Wake turbulence quantities are included by relating the turbulence velocities and lengthscales to readily determined mean aerodynamic quantities. No adjustable constants are used in the model. Predictions are in reasonable agreement with sound power spectral measurements made by Boeing for a variety of fan speeds, loading conditions and stator vane numbers. A study has been completed of the relationship between mean squared pressure in a duct and the transmitted sound power, under conditions of multimode sound propagation and uniform mean flow. This relationship has been computed for a family of source distributions that include, as special cases, incoherent monopole and dipole sources uniformly distributed over a duct cross section.

Active Control of Fan Tones The possibility exists that fan blade-passing tones can be controlled by deliberately introducing wake disturbances upstream of the rotor. An active control system is being implemented on a model fan. Predictions of the control of a single mode in an infinite duct have shown that substantial control performance is theoretically possible using a single ring of sources and sensors. Criteria have been established for choosing the optimal numbers of sources and sensors. Work is underway aimed at determining optimal control geometry from the point of view of robust system conditioning. Reflective terminations will also be introduced into the infinite duct model.

(iv) Passenger Car Aeroacoustics Over the past decade, aeroacoustic noise in automobiles has become a significant issue for driver comfort, and vehicle designers are seeking improved design tools to allow them to ensure aeroacoustically quiet cars in the early stages of the design process. In response to these needs Dr M C M Wright is working with Renault, DaimlerChrysler, Free-Field Technologies S.A. and Numeca International in the EU project SMILE (Simulation

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Methods of Interior Levels aerodynamically Excited). ISVR's contribution has involved Dr W G Dewar making detailed flow and noise measurements around a Renault-manufactured car model in the School of Engineering Sciences’ 7' × 5' wind tunnel. The aim is to provide semi empirical tools which will allow vehicle designers to use standard techniques such as CFD to achieve low noise designs without the necessity for expensive full-scale wind-tunnel testing. Another new project supported by the car manufacturer Renault aims to investigate the acoustical behaviour of an automotive ventilation outlet system; it includes acoustical measurements on actual automotive ventilation outlet systems and on simplified full-scale models, the identification of the main aeroacoustic mechanisms and, eventually, their modelling. The final goal is to identify possible noise mitigation procedures, test them and make recommendations to designers.

Electroacoustics, Virtual Acoustics, Imaging, and Inverse Methods Work has continued on the application of inverse techniques for the quantification of acoustic source strength distributions. In particular, a major Rolls-Royce funded project has concentrated on the application of inverse methods to the identification of acoustic sources in reverberant environments. Of particular interest has been the relationship between these techniques, which involve the inversion of a matrix of Green functions relating acoustic source strength to measured acoustic pressures, and those methods which make use of focused beamforming solutions. A series of experiments undertaken in the ISVR anechoic chamber has succeeded in clearly illustrating the difference between the methods involved and has shown that considerable errors in the estimate of acoustic source strength are produced by the application of beamforming arrays. Furthermore, experiments involving the introduction of reflecting surfaces have demonstrated that the effect of reflections can be compensated for, provided that the relevant Green functions can be measured a priori. These techniques are now being extended for application to the identification of the acoustic source strength distributions at the inlet of a laboratory based fan-duct system. Inverse methods have also been applied successfully to the identification of unsteady forces generated in a hard disk drive system. In this case, the matrix to be inverted consisted of components identified through the application of a finite element model. The values of unsteady force deduced were found to be in good agreement with directly measured experimental values. It was noted, however, that the problem became ill-conditioned at frequencies where a single resonance of the structure dominated the response. A technique involving the perturbation of these resonances through the addition of further mass/stiffness was found to show some promise in alleviating this difficulty. This work was undertaken jointly with Dr T P Waters of the Dynamics Group and was sponsored by the Samsung Institute of Technology, Korea. The development of visually adaptive imaging systems has continued with fundamental studies of the influence of loudspeakers placed asymmetrically with respect to the listener. It has been found that the virtual imaging system remains remarkably robust to lateral deviations from the symmetric condition and both theoretical and experimental work has been undertaken with a view to providing a better understanding of the factors which influence the performance of systems under these conditions. A further study has also recently been undertaken which has examined the effect of movement of the loudspeaker system relative to the listener’s head. It has consistently been found that it is easier to generate stable virtual acoustic images when the movement of the loudspeaker system is towards the position of the virtual image. A further project is considering the design of multi-channel digital filtering systems for use in virtual acoustic imaging systems. The challenge here is to implement the inverse filters necessary with minimum computational load. This increasingly becomes an issue as the adoption of virtual imaging techniques becomes more widespread. An important factor involved in this work is the extent to which additional delay in the delivery of the audio signal can be tolerated when coupled with the visual signals associated with video imaging. The previously reported work on the ‘Optimal Source Distribution’ for virtual acoustic imaging has now reached fruition. A comprehensive series of subjective experiments has been undertaken in order to evaluate the full capabilities of such systems. The approach taken involves making use of a pair of very closely spaced loudspeakers (subtending an angle of approximately 6o at the listener) for high frequency transmission, another pair of loudspeakers at approximately 30o for the delivery of mid-frequency, and another pair spaced at 180o for the delivery of the low frequency end of the audio spectrum. Comprehensive subjective experiments have clearly illustrated the efficiency with which virtual images can be produced by such an arrangement which has been

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found to outperform the previously developed ‘Stereo Dipole’ system involving a single pair of loudspeakers subtending an angle of about 10o at the listener. The measurement of normal incidence acoustic reflection coefficients by using multiple microphone methods has produced some excellent results. It has been clearly demonstrated that the conventional ‘two microphone’ transfer function method can be extended significantly in operational bandwidth by the introduction of multiple microphones with appropriately chosen spacing. A least squares method has been developed which enables the estimation of acoustic reflection coefficients for plane wave propagation over a much wider frequency range than has hitherto been possible. The more challenging topic of measuring acoustic reflection coefficients associated with obliquely incident sound is currently being tackled. Work has been initiated on a multi-channel signal processing technique for enhancing live sound recordings. An investigation has been undertaken of the directivity of circular arrays of microphones mounted on a rigid sphere. A conventional approach has been taken to the determination of the filters associated with each sensor output in order to derive an optimal estimate of the recorded time history associated with a source in a specific angular location. The response of this array to sources at other, sub-optimal, locations has then been calculated. It was found that, as may be expected, the circular microphone array did not suffer from the angular ambiguity associated with a simple linear array and, perhaps more surprisingly, that the inclusion of the scattering sphere appeared to produce a more advantageous directivity pattern at low frequencies. It is hoped that support may be found for a continuation of this research.

Statistical Energy Analysis and Vibroacoustics Work by Dr M C M Wright on the application of the periodic orbit theory of semiclassical physics to problems in sound and vibration continues in collaboration with Dr C J Howls (Faculty of Mathematical Studies) and has been rewarded by the announcement of an EPSRC Advanced Research Fellowship which will allow him to concentrate exclusively on this area for the next five years. The work consists of applying mathematical tools that were originally developed in quantum mechanics to the vibrations of cavities, membranes and plates. The important feature of this description is that it allows the modal behaviour of a system to be related to its geometry through the periodic orbits which form repeating ray paths. It is hoped that this will lead to improved efficiencies in the design of quiet structures. The effects of quantum chaos in the ray trajectories on the modal statistics is also being investigated.

Flow measurements being made to determine sources of aerodynamic interior noise in cars Further experimental evidence has been obtained of the contribution of longitudinal string vibration to violin sound. A novel approach to the estimation of the mobility at a bridge, and of input power from transverse and longitudinal string vibrations, has been developed.

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Hydroacoustics Last year an historic sea trial was undertaken at Hurst Spit, Milford-on-Sea where a variety of bubble-related measurements were made. This year (November 2001) a follow-up sea trial was very successful. Not only were pioneering measurements of bubble populations made, but the acoustic data was analysed to determine the effect of assumption critical to state-of-the-art methods of obtaining bubble populations from acoustic measurements. In addition a new theory for acoustic propagation in bubbly water was developed and applied in an inversion to obtain bubble population estimates without resort to the assumptions inherent in the state-of-the-art method (i.e. monochromaticity, steady-state, linear, free-field bubble pulsations). The results were presented in the Inaugural Medwin Prize lecture and also to the EPSRC Theme day on Acoustics. A deployment of the combination-frequency system pioneered by ISVR was attempted during the sea trial, as were Higher Order Spectral studies of acoustic scatter from bubbles, and measurement of bubble passive emissions. The results were used to compare with a model of bubble cloud evolution below breaking waves, with successful time-histories of the sizes and distributions of thousands of bubbles being predicted on the basis of given prevailing ocean conditions. In collaboration with QinetiQ, Winfrith, measurements of visco-inertial absorption in dilute particulate suspensions of non-spherical particles have been analysed using three different methods for characterising the particle size distribution: laser diffraction, gravitational sedimentation and centrifugal sedimentation. The different distributions given by each for irregular particles are interpreted in terms of the underlying physics. Recent comparisons between a model for acoustic absorption by oblate and prolate spheroids and measurements made with plate-like kaolin particles show excellent agreement. The additional volume attenuation due to solid particles in suspension and microbubbles, and the effect of microbubbles on phase speed and volume reverberation have been included in a ray-method sonar performance model. The collaborative two-pronged approach with the School of Ocean and Earth Science (SOES) to estimate the geoacoustic properties of marine sediments continues. First, field trials of a new in situ acoustic probe, Sediment Probing Acoustic Detection Equipment (SPADE) provided compressional wave velocity and attenuation from 10 to 75 kHz, with the potential to extend beyond 100 kHz (to date the high frequency limit has been 50 kHz). In addition, Instantaneous Frequency (IF) techniques have been applied to normal incidence chirp reflection data, with the optimum IF estimation technique selected. Second, a 3D Chirp sub-bottom profiling system was developed and deployed off the north coast of the Isle of Wight using a new source catamaran. Sea floor reflection amplitudes of a seismic system were modelled on the basis of the component directivities and the reflection geometry to address horizontal resolution and spatial aliasing issues. Collaborations with the Chemistry Department continue to produce pioneering work, with electrochemical measurements of mass flux associated with acoustically-induced surface waves on bubble walls, of the rate of oxygen transfer across the gas liquid interface of a bubble, and of the rate of growth of a bubble through rectified diffusion. The influence of surfactants on these processes has also been investigated. Surface waves driven acoustically on a moving gas bubble have been detected electrochemically for the first time. Measurements of the threshold for generation of these waves, and of the transient growth period before these waves reach steady state is being compared with theory developed in collaboration with a scientist from the Pacific Oceanological Institute, Vladivostok. A good start was made to a collaborative venture with the Belarus State University on examining the use of monitoring changes in the meniscus within a capillary to manufacture a robust sensor for cavitation.

Bioacoustics and Biomechanics Progress continues on a novel ultrasonic measurement technique to aid clinical bone assessment. Following the stage one in vivo trials in 2000, which used a simple rig to measure ultrasonic velocity through the human heel bone, a second, more complex rig was designed, constructed and tested in conjunction with the Medical Physics and Bioengineering Department at Southampton General Hospital. This stage two rig was then used in a pilot study on volunteers, and appeared to show propagation of two distinct modes through the heel bone at certain angles of incidence. Further in vivo trials confirmed the existence of such waves, believed to be the fast and slow waves of Biot theory for porous media. If this is the case, it represents a significant finding in the field of ultrasonic bone assessment. A larger clinical trial is currently being performed to assess the response of these modes to deterioration in the bone tissue through the disease osteoporosis.

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A second project aims to quantify the efficacy of clinical lithotripsy using the passive acoustic emissions that it generates. This project contains both experimental and CFD components, and involves ISVR, Guy’s and St Thomas’ NHS Hospital Trust, London, and the School of Engineering Sciences. In the past year experimental work has included mapping of the acoustic shock wave source field, and producing a time-frequency waveform analysis system.

Power Ultrasonics A new electrochemical method for the detection of radicals produced by cavitation has been developed. This system targets both H• and OH• radicals produced through water cleavage as a result of the high temperatures and pressures generated in cavitation bubble collapse. This acoustoelectrochemical detection system is able to detect radical generation rates, through a coupled redox active trapping agent, in the order of nmol dm-3 s-1. A newly-developed axisymmetric free-Lagrange code has been used to simulate the interaction between a strong underwater shock wave and a spherical bubble. Validation of the numerical results obtained using the code has been carried out and the results agree well with published results. The intention is to predict the scattered far-field radiation and compare with measurements by using the code to simulate interaction of an air bubble with a lithotripter pulse.


2.1 Aeroacoustics and Non-linear Acoustics 2.1.1 Benchmark studies of the ACTRAN code for duct acoustics (R J Astley, M C M Wright, P F Joseph,

A McAlpine) 2.1.2 Influence of a distorted fan inlet mean flow on the tonal noise of an in-duct fan (M C M Wright,

X Laparra) 2.1.3 Fan noise assessment from in-duct pressure measurements (P F Joseph) 2.1.4 Fan noise reduction using flow control (V Kota, M C M Wright) 2.1.5 Prediction and control of the noise from turbines (P F Joseph) 2.1.6 Engineering models for broadband fan noise prediction (P F Joseph, Q Zhou) 2.1.7 Accuracy improvements in measuring aircraft noise events (K R Holland, D Wallis) 2.1.8 Multi-mode sound power measurement in flow ducts (P F Joseph) 2.1.9 Active control of low frequency buzz-saw tones (SILENCE(R)) (P F Joseph, M Wilkinson,

M J Fisher) 2.1.10 Control methods for the noise of supersonic tip speed fans (SILENCE(R)) (M J Fisher, A McAlpine;

B J Tester [Rolls-Royce plc]) 2.1.11 The influence of acoustic liners on buzz-saw noise (M J Fisher, A McAlpine; B J Tester [Rolls-

Royce plc]) 2.1.12 Numerical methods for duct acoustics (SILENCE(R)) (R J Astley, M C M Wright, J A Hamilton,

A McAlpine) 2.1.13 Non-linear propagation of tones in lined ducts (A McAlpine, M J Fisher) 2.1.14 Simulation of the flow past laminar-flow control aerofoils (P A Nelson; O R Tutty [School of

Engineering Sciences]) 2.1.15 The prediction of acoustic loads on aircraft structures for acoustic fatigue assessment (M J Fisher,

R H Self, J Battaner-Moro, A L Bassetti) 2.1.16 A CFD coupled acoustic approach for the prediction of coaxial jet noise (M J Fisher, R H Self,

A L Bassetti; J McGuirk, G Page [Loughborough University]) 2.1.17 Jet exhaust aerodynamics and noise (JEAN) (M J Fisher, R H Self, C Williams) 2.1.18 Wind tunnel experiments for passenger car aeroacoustics (SMILE) (M C M Wright, G Dewar) 2.1.19 Reduction of airframe and installation noise (M G Smith) 2.1.20 Sound radiation from wall-bounded turbulent flow (C L Morfey; Z Hu, N D Sandham [School of

Engineering Sciences]) 2.1.21 Sound transmission through flows with mean shear (M G Smith, C L Morfey) 2.1.22 CFD prediction of turbomachinery noise (X Zhang [School of Engineering Sciences]; X Chen,

C L Morfey, P A Nelson)

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2.1.23 Hybrid models of IC engine breathing acoustics (P O A L Davies; M F Harrison [Cranfield University])

2.1.24 Parametric study of optimised silencer acoustic design (P O A L Davies, D C Van der Walt) 2.1.25 Sources of flow-induced pressure pulsations in pipes (P O A L Davies, K R Holland) 2.1.26 Aeroacoustic modelling of intake/exhaust noise sources (P O A L Davies, K R Holland) 2.1.27 Low-frequency noise in ventilation systems (M J Fisher, P Brandstätt) 2.1.28 ACTRAN numerical analysis of turbofan inlet liners (SILENCE(R)) (R J Astley, J A Hamilton) 2.1.29 ACTRAN analysis of liner splice effects in turbofan inlets (SILENCE(R)) (M C M Wright) 2.1.30 Theoretical models for liner splice effects in turbofan inlets (B J Tester [Rolls-Royce plc];

A McAlpine, M C M Wright) 2.1.31 The development of fast transient finite/infinite element models for unbounded wave problems

(J A Hamilton, R J Astley) 2.1.32 Effective numerical models for turbofan bypass ducts (V J T Hii, R J Astley) 2.1.33 CAA modelling of fan noise propagation (TURBONOISE CFD) (X X Chen, X Zhang [School of

Engineering Sciences]; C L Morfey, R J Astley) 2.1.34 Numerical methods for duct acoustic propagation and radiation – new development (V J T Hii,

R J Astley) 2.1.35 Mode scattering in non-uniformly lined inlet ducts (R J Astley, M C M Wright, A McAlpine; B J Tester

[Rolls-Royce plc]) 2.1.36 Sound radiation from a plane turbulent jet (C L Morfey; Z Hu, N D Sandham [School of Engineering

Sciences]) 2.1.37 Aeroacoustic behaviour of an automotive ventilation outlet system (M C M Wright, S Guérin) 2.1.38 Evaluation of linear experimental techniques applied to high amplitude pressure wave measurement

analysis for highly reactive conditions (P O A L Davies, K R Holland, D C Van der Walt) 2.1.39 Acoustic modelling of turbocharger compressor (P O A L Davies, J D Dixon, M J Parker) 2.1.40 Prediction methods for landing gears and flaps in turbulent flow (SILENCE(R)) (M G Smith,

J Carrilho)

2.2 Electroacoustics, Virtual Acoustics, Imaging, and Inverse Methods 2.2.1 Inverse filtering in multi-channel sound reproduction systems (P A Nelson; T Takeuchi [Kajima

Technical Research Institute, Japan]; H Hamada [Tokyo Denki University]) 2.2.2 Multi-channel sound reproduction (P A Nelson; H Hamada [Tokyo Denki University]; Y Kahana

[Phone-Or, Israel]) 2.2.3 Investigation of the properties of ‘Stereo Dipole’ sound reproduction (T Takeuchi [Kajima Technical

Research Institute, Japan]; P A Nelson) 2.2.4 Filter design for virtual acoustic imaging systems (P A Nelson, T Papadopoulos) 2.2.5 Numerical modelling of head-related transfer functions (P A Nelson, M Petyt; Y Kahana [Phone-Or,

Israel]) 2.2.6 Visually adaptive virtual sound imaging (P A Nelson, B Rafaely, J Rose) 2.2.7 Measurement of acoustic reflection coefficients (P A Nelson, Y Cho) 2.2.8 Array signal processing for test cell acoustic measurements (P A Nelson, K R Holland) 2.2.9 Sound image localization for headphone listening (P A Nelson, I Chun) 2.2.10 Regularisation methods in acoustic inverse problems (P A Nelson, Y Kim) 2.2.11 Spatial resolution limits for the reconstruction of acoustic source strength by inverse methods

(P A Nelson, Y Kim) 2.2.12 Numerical modelling of vibration and sound sources in hard disk drives by inverse methods (J T Kim,

T P Waters, P A Nelson) 2.2.13 An investigation into the performance of an empirically designed sound absorber for recording studio

control rooms (K R Holland, S Colam, P F Joseph) 2.2.14 Acoustic source strength reconstruction in reverberant environments (P A Nelson, K R Holland) 2.2.15 Active resonators in the modal sound field of a damped rectangular enclosure (S Zimmermann,

P F Joseph) 2.2.16 Numerical modelling of a miniature loudspeaker (I Chun, P A Nelson) 2.2.17 Optimal focusing of underwater acoustic arrays (P A Nelson, P F Joseph; B Cazzolato [University of

Adelaide])

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2.3 Statistical Energy Analysis and Vibroacoustics 2.3.1 Discrete-time LQG feedback control of vibrations (S J Sharp [Pennsylvania State University];

P A Nelson, M C M Wright) 2.3.2 The effect of longitudinal string vibration on violin sound (F J Fahy, N Harris) 2.3.3 Periodic orbit theory in sound and vibration (M C M Wright; C J Howls [Department of Mathematics])

2.4 Hydroacoustics 2.4.1 Sonoluminescence emitted during cavitation erosion of turbine blades (T G Leighton; J Field

[Cavendish Laboratory, University of Cambridge]; M Farhat, F Avellan [Ecole Polytechnique Fédérale de Lausanne])

2.4.2 A 3D chirp sub-bottom profiling system – a new tool for delineating the sub seabed (J M Bull, J K Dix, T Henstock, M Gutowski [School of Ocean and Earth Science]; T G Leighton, P R White)

2.4.3 Prediction of the seismic and geotechnical properties of gassy sea floor (T G Leighton, P R White; A I Best [Southampton Oceanography Centre]; J K Dix, J M Bull [School of Ocean and Earth Science])

2.4.4 Estimation of the time, location and natural frequency of entrained bubbles, through identification of individual bubble signatures in a severely overlapping, noisy surf zone environment (G T Yim, P R White, T G Leighton)

2.4.5 Study of the near-surface oceanic bubble population (T G Leighton, M D Simpson) 2.4.6 The rapid assessment of bubble population in shallow water for the enhancement of high-frequency

sonar operation (T G Leighton, S D Meers, M D Simpson) 2.4.7 An electrochemical study of bubble phenomena (P R Birkin [Department of Chemistry]; Y E Watson,

T G Leighton) 2.4.8 Mass flux across the atmosphere/ocean interface and detection of bubble populations (M D Simpson,

T G Leighton) 2.4.9 Acoustic properties of water containing suspended sediments (S D Richards [QinetiQ, Winfrith];

T G Leighton; N R Brown [Industrial Research Limited, New Zealand]) 2.4.10 Acoustic penetration of the seabed with particular application to the detection of non-metallic cables

(R Evans [Sira Ltd]; T G Leighton) 2.4.11 Bubble detection by passive and active non-resonant acoustic techniques (G T Yim, T G Leighton,

P R White) 2.4.12 Acoustic modelling of flow control valves (C L Morfey; B O Olsen [Danish Academy of Technical

Sciences, Danfoss AS]) 2.4.13 The use of capillary as a sensor of cavitation (N V Dezhkunov [Belarus State University];

T G Leighton) 2.4.14 Theoretical studies of the generation of surface waves on a bubble wall [A O Maksimov

[Pacific Oceanological Institute, Vladivostok, Russia]; T G Leighton) 2.4.15 Estimation of the in situ geoacoustic properties of marine sediments (T G Leighton, P R White; A I Best

[Southampton Oceanography Centre]; J K Dix, J M Bull, G B O Robb [School of Ocean and Earth Science])

2.4.16 Very high frequency acoustic scattering for MCM classification modelling (T G Leighton; J K Dix [School of Ocean and Earth Science]; M D Simpson, P R White, R J Astley; G J Heald, R Brothers [QinetiQ, Winfrith])

2.4.17 The time-dependent acoustics response of oceanic bubbles clouds (T G Leighton, P R White; H A Dumbrell [QinetiQ, Bincleaves]; G J Heald [QinetiQ, Winfrith])

2.5 Bioacoustics and Biomechanics 2.5.1 Acoustic cavitation associated with ultrasonic dental scalers (T G Leighton) 2.5.2 Ultrasonic contrast agents (T G Leighton) 2.5.3 The development of a validated system for the ultrasonic diagnosis of osteoporosis (E R Hughes,

T G Leighton, P R White, R C Chivers; G W Petley [Medical Physics and Bioengineering Department, Southampton General Hospital])

2.5.4 Development of an in-vivo acoustic diagnostic for lithotripter-induced shock-tissue interaction (T G Leighton; G J Ball [School of Engineering Sciences]; A J Coleman, F Fedele [Guy's and St Thomas' NHS Hospital Trust, London])

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2.6 Power Ultrasonics 2.6.1 Characterisation of cavitation using electrochemical, acoustic and luminescent techniques (P R Birkin

[Department of Chemistry]; J F Power, T G Leighton) 2.6.2 A free-Lagrange simulation to study the shock-induced collapse of a cylindrical air cavity in water

(G J Ball [School of Engineering Sciences]; T G Leighton, A R Jamaluddin) 2.6.3 An investigation of surface reformation in the presence of inertial (transient) cavitation (P R Birkin,

D Offin [Department of Chemistry]; T G Leighton)

Publications Astley, R.J. and *Coyette, J.-P. Conditioning of infinite element schemes for wave problems. Communications in Numerical Methods in Engineering, 17(1), 2001, 31-41. The performance of spheroidal infinite elements. International Journal for Numerical Methods in Engineering, 52, 2001, 1379-96. Astley, R.J. and Hamilton, J.A. The stability of infinite elements schemes for transient acoustics. 2nd European Conference on Computational Mechanics – Solids Structures and Coupled Problems in Engineering, Cracow, Poland, 26-29 June 2001, 16pp. Infinite elements for transient flow acoustics. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2273, 28-30 May 2001, 10pp. *Lagrouche, O., *Bettess, P. and Astley, R.J. Approximating systems of plane waves for the solution Helmholtz equation at high frequency: Integration and conditioning. European Congress on Computational Methods in Applied Sciences and Engineering, ECCOMAS Computational Fluid Dynamics Conference 2001, Swansea, Wales, 4-7 September 2001, 15pp. Davies, P.O.A.L. and Holland, K.R. The observed aeroacoustic behaviour of some flow-excited expansion chambers. Journal of Sound and Vibration, 239(4), 2001, 695-708. Davies, P.O.A.L., Holland, K.R. and Van der Walt, D.C. Measurement and control of flow generated noise. Proceedings of the 17th International Congress on Acoustics, Rome, Italy, Session 4A.10.01, 2-7 September 2001, 107. Doak, P.E. Editor-in-Chief, Journal of Sound and Vibration, Academic Press, published weekly commencing with 239(1), 2001. Hamilton, J.A. and Astley, R.J. Exact solutions for transient spherical radiation. Journal of the Acoustical Society of America, 109, 2001, 1848-58. Holland, K.R. The Definitive Loudspeaker Review (Objective Review of Studio Monitor Loudspeaker Systems). Studio Sound, 43(1-12), 2001, 24pp. Principles of sound radiation. In: Borwick, J. ed. Loudspeaker and Headphone Handbook, Butterworth-Heinemann, 2001, 1-43. *Newell, P.R., Holland, K.R. and *Newell, J.P. The Yamaha NS10M: Twenty years a reference monitor. Why? Proceedings of the Institute of Acoustics, 23(8), 2001, 29-40. Why the NS-10? Studio Sound, 43(12), 2001, 44-52. Hughes, E.R., Leighton, T.G., *Petley, G.W. and White, P.R. A review of scattering modes for ultrasonic propagation in trabecular bone, ISVR Technical Report 293, Southampton, University of Southampton, 2001, 19pp.

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Ultrasonic assessment of bone health. Acoustics Bulletin, 26(5), 2001, 17-23. Joseph, P.F. A technique for the measurement of the plane wave reflection coefficient of shallow water seabeds. Proceedings of the Institute of Acoustics, Acoustical Oceanography 2001, Southampton, UK, 23(2), 2001, 51-9. Joseph, P.F. and *Parry, A. Rotor/wall boundary layer interaction broadband noise in turbofan engines. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2244, 28-30 May 2001, 11pp. Joseph, P.F., *Fruteau, E. and Nelson, P.A. Design rules and sensing strategies for the active control of turbofan engine noise. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2222, 28-30 May 2001, 11pp. Joseph, P.F., Morfey, C.L. and Lowis, C. In-duct acoustic pressure measurements for sound power determination in ducts with flow (Keynote Address). Proceedings of the Twentieth Anniversary Meeting of the Acoustical Society of Korea, Cheju Island, Korea, 2001, 13-36. *Cox, B.T. and Joseph, P.F. Modal dispersion curve measurement for the robust inversion of shallow water seabed parameters. Proceedings of the 17th International Congress on Acoustics, Rome, Italy, Session 4P.11, 2-7 September 2001, 139. Leighton, T.G. Surf zone bubble spectrometry: The role of the acoustic cross section (Plenary Address given at the Inaugural Award of the Medwin Prize for Acoustical Oceanography). Journal of the Acoustical Society of America, 110(5) Part 2, 2001, 2694. The acoustics of gas bubbles in liquids (Keynote Paper). Anglo-French Physical Acoustics Group Meeting, Institute of Physics, 2001, 7. Leighton, T.G., *Farhat, M., *Field, J.E. and *Avellan, F. Luminescence from hydrodynamic cavitation: Method and preliminary analysis, ISVR Technical Report 294, Southampton, University of Southampton, 2001, 36pp. Leighton, T.G., *Heald, G.J., *Griffiths, H. and *Griffiths, G. eds. Proceedings of the Institute of Acoustics Conference on Acoustical Oceanography. Bath, Bath University Press, 2001, 424pp. Leighton, T.G., Meers, S.D., Simpson, M.D., *Clarke, J.W.L., Yim, G.T., *Birkin, P.B., *Watson, Y.E., White, P.R., *Heald, G.J., *Dumbrell, H.A., *Culver, R.L. and *Richards, S.D. The Hurst Spit Experiment: The characterisation of bubbles in the surf zone using multiple acoustic techniques. Proceedings of the Institute of Acoustics, Acoustical Oceanography 2001, Southampton, UK, 23(2), 2001, 227-34. *Birkin, P.R., *Power, J.F. and Leighton, T.G. Electrochemical evidence of H* produced by ultrasound. Journal of the Chemical Society Chemical Communications, 21, 2001, 2230-1. *Birkin, P.R., *Watson, Y.E. and Leighton, T.G. Efficient mass transfer from an acoustically oscillated gas bubble. Journal of the Chemical Society Chemical Communications, 24, 2001, 2650-1. *Birkin, P.R., Leighton, T.G., *Watson, Y.E. and *Power, J.F. Acoustoelectrochemistry. Acoustics Bulletin, 26(5), 2001, 24-37. *Birkin, P.R., *Watson, Y.E., *Smith, K.L., Leighton, T.G. and Simpson, M.D. Measurement of species flux from a bubble using an acousto-electrochemical technique. Proceedings of the Institute of Acoustics, Acoustical Oceanography 2001, Southampton, UK, 23(2), 2001, 242-9. *Cunningham, K.B., *Coleman, A., Leighton, T.G. and White, P.R. Characterising in vivo acoustic cavitation during lithotripsy with time-frequency methods. Acoustics Bulletin, 26(5), 2001, 10-16.

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*Maksimov, A.O. and Leighton, T.G. Transient processes near the threshold of acoustically driven bubble shape oscillations. Acta Acustica, 87(3), 2001, 322-32. *Richards, S.D. and Leighton, T.G. Sonar performance in coastal environments: Suspended sediments and microbubbles. Acoustics Bulletin, 26(1), 2001, 10-17. Acoustic sensor performance in coastal waters: Solid suspensions and bubbles. Proceedings of the Institute of Acoustics, Acoustical Oceanography 2001, Southampton, UK, 23(2), 2001, 399-406. McAlpine, A. and Fisher, M.J. The effect of acoustic lining on “Buzz-saw” noise generated by an aero-engine. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2201, 28-30 May 2001, 11pp. On the prediction of “Buzz-saw” noise in aero-engine inlet ducts. Journal of Sound and Vibration, 248(1), 2001, 123-49. Meers, S.D., Leighton, T.G., Clarke, J.W.L., *Heald, G.J., *Dumbrell, H.A. and White, P.R. The importance of bubble ring-up and pulse length dependence in estimating the bubble distribution from acoustic propagation measurements. Proceedings of the Institute of Acoustics, Acoustical Oceanography 2001, Southampton, UK, 23(2), 2001, 235-41. Morfey, C.L. Mechanisms for jet mixing noise – Fundamental problems in aeroacoustics (Invited Paper). Proceedings of the AeroAcoustics Research Consortium Jet Noise Workshop, Ohio Aerospace Institute, Cleveland, USA, 7-9 November 2001. Morfey, C.L. and Joseph, P.F. Shear layer refraction corrections for off-axis sources in a jet flow. Journal of Sound and Vibration, 239(4), 2001, 817-46. Morfey, C.L. and *Tan, M. Unsteady drag on a cylinder due to transverse oscillation at finite amplitude. Journal of Sound and Vibration, 246(4), 2001, 705-21. *Béquin, P. and Morfey, C.L. Weak nonlinear propagation of sound in a finite exponential horn. Journal of the Acoustical Society of America, 109(6), 2001, 2649-59. *Bradshaw, D.R.S. and Morfey, C.L. Pressure and shear responses in brain injury models. Proceedings of the 17th International Technical Conference on the Enhanced Safety of Vehicles, Amsterdam, The Netherlands, 4-7 June 2001. National Highway Traffic Safety Administration, US Department of Transportation, 2001, 10pp. *Bradshaw, D.R.S., *Ivarsson, J., Morfey, C.L. and *Viano, D.C. Simulation of acute subdural haematoma and diffuse axonal injury in coronal head impact. Journal of Biomechanics, 34, 2001, 85-94. *Hu, Z.W., Morfey, C.L., *Sandham, N.D. Aeroacoustics of wall-bounded turbulent flows. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2172, 28-30 May 2001, 11pp. Nelson, P.A. Review of some inverse problems in acoustics. International Journal of Acoustics and Vibration, 6(3), 2001, 118-34. Nelson, P.A. and *Kahana, Y. Spherical harmonics, singular-value decomposition and the head-related transfer function. Special Edition of Journal of Sound and Vibration, 239(4), 2001, 607-38. *Cazzolato, B.S., Nelson, P.A., Joseph, P.F. and *Brind, R.J. Numerical simulation of optimal deconvolution in a shallow-water environment. Journal of the Acoustical Society of America, 110(1), 2001, 170-85. *Hill, P.A., Nelson, P.A., *Kirkeby, O. and *Hamada, H. Resolution of front-back confusion in virtual acoustic imaging systems. Journal of the Acoustical Society of America, 108(6), 2001, 2901-10.

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*Pitelet, C., Wright, M.C.M. and Nelson, P.A. Optimization of flow distortions for fan noise reduction with one-sided actuators. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2219, 28-30 May 2001, 5pp. *Takeuchi, T. and Nelson, P.A. Optimal source distribution system for virtual acoustic imaging. 110th Convention of the Audio Engineering Society, Amsterdam, The Netherlands, Paper 5372, 12-15 May 2001, 13pp. Robustness to head misalignment of virtual sound imaging systems. Journal of the Acoustical Society of America, 109(3), 2001, 958-71. *Tutty, O.R., *Hackenberg, P. and Nelson, P.A. Numerical optimisation of the suction distribution for laminar flow control. AIAA Journal, 38(2), 2000, 370-2. *Bréard, C., *Sayma, A., *Imregun, M., *Wilson, A.G. and Tester, B.J. A CFD-based non-linear model for the prediction of tone noise in lined ducts. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA-2001-2181, 28-30 May 2001. *Dupere, I.D.J., *Dawes, W.N., Tester, B.J. and *Wilson, A.G. Predictions of rotor alone tones in a transonic fan using steady CFD. 39th AIAA Aerospace Sciences Meeting, Nevada, USA, AIAA-2001-0822, 2001. Predictions of multiple tone noise and distortion noise in a transonic fan using unsteady CFD. 4th European Conference of Turbomachinery, Fluid Dynamics and Thermodynamics, Firenze, Italy, 2001. *Rademaker, E.D., *Sijtsma, P. and Tester, B.J. Mode detection with an optimised array in a model turbofan engine intake at varying shaft speeds. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2181, 28-30 May 2001. Rose, J., Nelson, P.A. and Rafaely, B. Variance of sweet spot size with head location for virtual audio. Proceedings of the 110th Convention of the Audio Engineering Society, Amsterdam, The Netherlands, Preprint 5391, 12-15 May 2001, 5pp. Rose, J., Nelson, P.A., Rafaely, B. and *Takeuchi, T. A study of virtual acoustic imaging systems for asymmetric listener locations, ISVR Technical Report 295, Southampton, University of Southampton, 2001, 38pp. Van der Walt, D.C. Measurement technique to assess the acoustic properties of a silencer component for transient engine conditions. Journal of Sound and Vibration, 243(5), 2001, 797-821. Wright, M.C.M. Variance of deviations from the average mode count for rectangular wave guides. Acoustics Research Letters Online, 2(1), 2001, 19-24. Wright, M.C.M. and Nelson, P.A. Wind tunnel experiments on the optimization of distributed suction for laminar flow control. Proceedings of IMechE, 215(G), 2001, 1-12. Yim, G.T., White, P.R. and Leighton, T.G. Estimation of the time, location and natural frequency of entrained bubbles, through identification of individual bubble signatures in a severely overlapping, noisy surf zone environment. Proceedings of the Institute of Acoustics, Acoustical Oceanography 2001, Southampton, UK, 23(2), 2001, 250-6. Zhou, Q., *Zhang, W. and Joseph, P.F. A new method of determining acoustic added mass and damping coefficient of fluid-structure interaction. Proceedings of the Eighth International Symposium on Practical Design of Ships and Other Floating Structures, Shanghai, China, 2, 2001, 1185-95. * - Not working in ISVR

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1.3 Human Sciences Group Group Chairman: Professor M J Griffin

Group Developments The Hearing and Balance Centre (HABC) once again ran a fully subscribed Balance 2001, a short course for professionals dealing with balance disorders, with lectures from the United States and the UK. The South of England Cochlear Implant Programme (SOECIC) hosted the Spring 2002 meeting of the British Cochlear Implant Group with over 100 participants. The Human Factors Research Unit participated in the 9th International Conference on Hand-Arm Vibration in June 2001, Nancy, France and contributed seven of the presented papers. Twelve papers were presented at the 36th UK Group Conference on Human Response to Vibration held at QinetiQ, Farnborough, in September 2001. A major new venture for the Group is planning for an undergraduate programme in Audiology in response to an invitation for bids from the Department of Health as part of the agenda for modernising audiology services in England. The envisaged 4-year programme will include a third year with students on clinical placements in NHS hospital departments paid trainee salaries. The bid is being prepared in partnership with the Hampshire and Isle of Wight Workforce Development Confederation, which is responsible for NHS education and training programmes. If the bid is successful, it will entail appointment of seven full-time equivalent teaching staff over the first four years of the programme. A European Union network of nine laboratories (The Vibration Injury Network, VINET) co-ordinated by the Human Factors Research Unit completed its task related to the development of uniform methods for the detection and prevention of injury due to vibration exposures at work. The network led to the design of a major 4-year investigation involving both epidemiology and experimental work. This research will again be co-ordinated by the Human Factors Research Unit and is one of several new EU sponsored projects in which the Unit will be involved during the coming years. The Unit has also been heavily involved in the development of a proposed EPSRC-funded Railway Research Centre jointly with Birmingham University.

Personnel Nawal Abdul Jalil joined the Human Factors Research Unit to conduct PhD research leading to the development of a model of body-seat dynamics during fore-aft vibration. Dr Yasunao Matsumoto, now a lecturer at Saitama University in Japan, returned for a short visit to conduct an experimental study of the non-linearity in subjective and biodynamic responses to vertical vibration. Professor Massimo Bovenzi of the University of Trieste visited the Human Factors Research Unit for the tenth successive year in connection with collaborative research into the acute and chronic effects of hand-transmitted vibration. Dr Wan-Sup Cheung of the Korean Research Institute for Standards and Science visited to collaborate in studies of biodynamic responses. Nathan Thomas joined the Hearing and Balance Centre to assist Dr Kapadia in the development of new techniques to record otoacoustic emissions. Graham Horswell commenced work with Professor Lutman on a five-year longitudinal study of effectiveness of the Noise at Work Regulations to prevent hearing loss in new recruits to industry. Daniel Rowan has commenced studies towards a PhD on the topic of binaural integration of cues with regard to signal-processing hearing aids and cochlear implants.

Research

Hearing and Balance Centre

Hearing Aids and Cochlear Implants The Hearing and Balance Centre continues to conduct a range of studies of the effectiveness of hearing aids and cochlear implants, with focus on new developments. A large-scale evaluation of modern digital hearing aids in comparison with more basic analogue instruments in the NHS was reported in the previous Annual Report. Related studies have involved evaluation of a digital signal processing algorithm for improving speech-to-noise ratio in hearing aids within an EU consortium, a health technology assessment of methods to achieve early acceptance of hearing aids by adults in collaboration with the MRC Institute of Hearing Research, and a

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fundamental study of auditory acclimatisation, which is the phenomenon whereby the auditory system adapts to make better use of sound amplified by hearing aids. The previous Annual Report also highlighted a new venture involving spatial hearing in the context of people using hearing aids and cochlear implants. This work has entailed the development of a spatial hearing test facility in the small anechoic room of the Rayleigh building and associated computer-controlled psychophysical procedures. Initial work has been funded by the hearing aid manufacturer, Phonak, whose instruments include adaptive systems to modify their directional characteristics. When instruments are worn on both ears there is the potential for the two instruments acting independently to cause disturbing effects. Studies completed during the year have examined speech recognition in noise in asymmetrical sound fields and also localisation ability with adaptive directional systems. There do not appear to be deleterious effects for speech recognition, localisation or subjective comfort while there are substantial benefits from increasing the effective signal-to-noise ratio at the ear from the adaptive system. In parallel with this work on hearing aids, two major studies on the benefits of bilateral cochlear implants, as opposed to the standard provision of implanting just one side have commenced, funded by the manufacturers Cochlear and Med-El. Recipients of a second implant have been tested on their localisation ability using the facilities in ISVR. Patients from SOECIC who volunteer will receive a second implant and will contribute to the trials. A study of localisation ability in unilateral cochlear implant users has been completed to provide comparison data. Results to date are showing large improvements in localisation ability for bilateral implants compared to unilateral, albeit inferior to binaural hearing aid users and normal listeners. This particular area of work is identified as a priority for the Hearing and Balance Centre and it is hoped to attract PhD students to address some of the fundamental issues associated with the integration of binaural/bilateral cues when processed by advanced digital hearing aids or cochlear implants.

Cochlear Function An investigation has been made of a recently reported phenomenon known as a ‘dead region’ in the cochlea. This is construed as a segment of the cochlear partition having no functioning inner hair cells and hence unable to transduce sound input at the corresponding frequency. However, spreading of sound input to adjacent regions as part of the travelling wave envelope due to normal cochlear mechanics means that sound at that frequency may be transduced by a region that usually responds to a different frequency. Studies completed during the year have utilised a new test for dead regions and shown that they appear to be common in ears with severe and profound hearing loss. This has ramifications for hearing aids because amplification of sounds at frequencies corresponding to dead regions may interfere with speech recognition. It is planned to prioritise the study of tests for dead regions and the consequences for amplification.

Vestibular Function Studies of quality of life have highlighted the mixture of physical limitations, somatic and psychosocial effects that follow dizziness. This research involving collaboration with the MRC Institute of Hearing Research has also shown that more than 20% of the general adult population are materially affected by dizziness. The human organism compensates over time for altered vestibular input, caused for example by disease or injury, although the mechanisms for this central nervous system plasticity are not well understood. Nonetheless, this process is utilised in programmes of vestibular rehabilitation, which involve a variety of management options including exercises. A study of vestibular rehabilitation is underway developing questionnaire instruments for assessing the benefits of vestibular rehabilitation and investigating factors that influence the process.

Noise-induced Hearing Loss Work has continued on the collection of suitable databases of noise-induced hearing loss, funded by Defeating Deafness, to address the issue of how noise and age effects may interact. This issue is important, both to understand the epidemiology of hearing loss and the assessment of compensation for noise-induced hearing loss, and is a matter debated repeatedly in parliament in the context of War Pensions. An international consensus development conference on the topic is being organised for November 2002 in collaboration with the MRC Institute of Hearing Research. A 5-year longitudinal study of new recruits to industry has commenced with funding from the Health and Safety Executive. Several hundred participants will be followed for 3 years using audiometry and new otoacoustic emissions measurements that are sensitive to small changes in cochlear function, as may occur as a result of

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excessive noise exposure. The aim is to determine whether compliance with the current Noise at Work Regulations is adequate to prevent noise-induced hearing loss.

Services The Hearing and Balance Centre continues to offer a wide range of audiological expertise for assessment and rehabilitation of patients with hearing or balance problems. This clinical service is important for supporting teaching of the MSc in Audiology and to underpin the research programme. The South of England Cochlear Implant Centre, SOECIC, continues to expand and now has 195 cochlear implant patients under its care. The first bilateral implant procedures have taken place and two adults have received a second device. These patients will contribute to the national research study mentioned below.

Subjective Acoustics Following an extended competitive tendering process, and previous pilot studies into aircraft noise and sleep co-ordinated by Dr Flindell, the Department for Transport awarded a large research contract to a multi-disciplinary team led by the MVA Consultancy to reassess attitudes to aircraft noise in England, investigate the correlation between attitude and the Leq noise index, and examine any willingness to ‘pay’, in relation to other elements on the basis of stated preference survey evidence. Dr Flindell is acting as technical adviser on aircraft noise to this team. The research is designed to underpin the Government’s stated principle set out in “A New Deal for Transport: Better for Everyone” (Cm3950) that the aviation industry should meet the external costs it imposes. The research contract is expected to last approximately three years and is split into two stages with Phase I focusing on the development of the sampling strategy and assessment of the feasibility of using Stated Preference techniques and an initial assessment of the Leq/annoyance relationship. Phase I is expected to last until the end of 2002. A decision to proceed to Phase II will depend on the Phase I findings. The Department expects the results of the research to be disseminated widely. Research into the subjective assessment of auditoria progressed during the year by focusing on the development and testing of psychoacoustic models to explain speech masking by delayed same-signal reinforcement. The work is intended to contribute to increased understanding of the detectability of direct sound sources, such as a live talker in the presence of reverberation or electro-acoustic reinforcement. Collaboration with the University of Valencia in Spain under which visiting scholars spend 6 months at ISVR studying the long term statistical behaviour of environmental noise levels has continued under the European ERASMUS student exchange scheme. This year, a visiting scholar spent around 6 months at ISVR investigating the relationships between noise complaints at Heathrow, Stansted and Gatwick airports against various possible explanatory factors such as the location of the complainant within published aircraft noise exposure contours and other factors such as recent developments of the airports. The work was extended for a further 2 months by another student from the University of Dortmund who was investigating the potential benefits for good community relations of operating ‘freefone’ noise lines at major airports. The previous final year ERASMUS student from the University of Valencia (2000-2001) returned to the Group in November 2001 to commence new research into Noise Mapping Uncertainties. This project is supported through Dr Andrew Bullmore of Hoare Lea Acoustics. Dr Bullmore recently moved to Hoare Lea Acoustics after having been Manager of ISVR Consultancy Services. A collaborative project with the Building Research Establishment on understanding the meaning of reported noise annoyance was extended during the year by carrying out exploratory qualitative interviews with people who had previously participated in a more conventional study (i.e. using conventionally structured questionnaires) of changes in road traffic noise annoyance consequent to the introduction of new road traffic noise mitigation measures.

Human Factors Research Unit

Biodynamics Systematic exploration of the mechanical impedance and transmissibility of the human body exposed to whole-body vibration has continued. This includes the quantification and modelling of forces in directions other than the direction of excitation and at points other than the point of excitation. It is thought that a better understanding

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is needed in these areas so as to improve biodynamic models of the body. Exploration of the form of the non-linearity of the biodynamic responses to vibration also seeks to quantify the extent of the large non-linearity in the dynamic response and how it depends on the input stimulus. Biodynamic models are being evolved to represent the input impedance of the seated body and how this is influenced by various factors, including inter-subject variability, intra-subject variability, and the presence and inclination of a seat backrest. The current goal is the simplest possible model that can be implemented in procedures used to predict the transmissibility of seats and construct anthropodynamic dummies representing the human body in a seat. The work now includes the development of a model that can represent forces in the fore-aft and vertical directions at the supporting seat surface and at the backrest.

Seating The transmission of fore-aft vibration to the body through seat backrests is of interest and is co-ordinated with research on biodynamic modelling and studies of discomfort caused by fore-aft vibration in vehicles. The research has included a comparison of seat transmissibility in cars and in the laboratory. The use of multiple-input methods has been shown to be necessary when quantifying the transmission of car floor vibration to a seat, especially when considering the fore-aft and lateral vibration on a seat backrest. The EU research programme entitled TESTOPS, co-ordinated by the Human Factors Research Unit, developed a standardised test for the end-stop impacts in suspension seats. The results of the study are available on a web site http://www.humanvibration.com. A recently awarded EU contract ‘Evaluation and improvement of suspension seat vibration isolation performance’ (VIBSEAT) will also be co-ordinated by the Human Factors Research Unit. The principal objectives of this project are to determine how the operators of on-road and off-road vehicles, rail vehicles and small marine craft can best be protected from horizontal and rotational vehicle vibration by using suspension seating. The project will develop a test method for assessing seat suspensions in response to horizontal and rotational motion and will also investigate methods of isolating vehicle operators in response to vibrations in these axes using theoretical models and prototypes. Field trials will provide representative vehicle motions using on- and off-road, rail and marine vehicles, and laboratory experiments will be conducted to assess the relevant human factors, especially impedance and discomfort. The development of anthropodynamic dummies continues for both conventional seats (such as in cars) and suspension seats (such as in off-road vehicles). This research is complemented by the biodynamic modelling research that indicates the desirable characteristics of such dummies.

Subjective Responses Psychophysical research on the perception of vibration at the limbs has investigated the dependence of discomfort on the frequency, the direction and the magnitude of vibration at the hands and the feet. The perception thresholds for vibration have also been determined. In addition to having practical value for some situations where the body is exposed to vibration (especially vehicles and tools), the results add to understanding of the mechanisms involved in the perception of vibration in the limbs. Laboratory studies are investigating the influence of fore-aft vibration and shock on driver comfort. The problem is complex in that discomfort caused by fore-aft vibration arises from vibration at the supporting seat surface, the backrest and the feet. In general, the relative contributions from these inputs vary with vibration frequency, vibration magnitude, and the phase between the inputs. During excitation with vertical vibration at a single point, analytical and experimental investigations of the influence of the phase response in frequency weighting filters used to predict human response to whole-body vibration found effects suggesting the effects of phase should be considered. However, in many situations the maximum effects are small compared with the effects of some other variables, including inter-subject variability, intra-subject variability (including the effects of posture), and non-linearity.

Health Effects Various tests for diagnosing disorders caused by hand-transmitted vibration are under investigation. The research has included the experimental investigation of methods of detecting situations in which a subject may

http://www.humanvibration.com/

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try to give a falsely high reading when tested for the neurological effects of hand-transmitted vibration using vibrotactile thresholds and thermotactile thresholds. The acute effects of hand-transmitted vibration on peripheral blood flow continue to be investigated in collaboration with Professor Bovenzi from the University of Trieste. The most recent experiment investigated the effects on blood flow caused by intermittent vibration in comparison with the effects of continuous vibration. Experimental comparisons of two plethysmographs used for measuring finger blood flow have shown differences that have been explained by a false assumption in the design of one commercially available system. A re-analysis of previous epidemiological studies of vibration-induced white finger in Italy and the UK have resulted in clear evidence that changes to the time-dependency and the frequency weighting in current standards would be likely to increase the accuracy of predicting vibration-induced white finger. The changes, which would also simplify the form of the current standards, are the subject of discussion in standardisation committees. Current research includes the investigation of methods of measuring vibration transmitted through gloves to the hand. An International standard proposes the use of a ‘hand-adapter’ for this purpose but the influence of the adapter characteristics (e.g. size, mass and rigidity) have previously not been explored. The EU-funded Biomed2 programme, ‘Vibration Injury Network’ (VINET), was concluded during the past year. The research, co-ordinated by the Human Factors Research Unit, sought to develop uniform methods for the detection and prevention of injuries caused by both hand-transmitted vibration and whole-body vibration. With nine partners in eight European countries, the programme allowed collaboration and exchange of information in diagnostic methods, biodynamic modelling, and prevention, for both whole-body vibration and hand-transmitted vibration. The results are available on a web site http://www.humanvibration.com. The EU has recently awarded a new contract, ‘Risks of Occupational Vibration Exposures’ (VIBRISKS), with the Human Factors Research Unit as co-ordinator of six European partners from six countries. VIBRISKS seeks to improve understanding of the risks of injury from hand-transmitted vibration and whole-body vibration by means of epidemiological studies supported by fundamental laboratory research. The studies of hand-transmitted vibration and whole-body vibration are designed to be mutually beneficial since they involve many common tools and procedures. The Human Factors Research Unit will also be participating in a European contract, ‘Contact Force Mapping for Characterisation of Hand-Held Vibrating Tools’ (VIBTOOL). The overall objective of this research is to improve standards for testing vibrating tools; this is to be achieved by improving the repeatability of vibration tests made on hand-held power tools by means of a measurement technique capable of mapping the contact pressure distribution between the hand and the handle of the tool. The project is focused on the development and characterisation of new sensors designed for that purpose. The Human Factors Research Unit will investigate the applicability of the method in laboratory experimental studies.

Performance Effects Modelling of the active and passive responses of the standing body exposed to horizontal motion remains an area of interest. Further experiments have been conducted on postural stability and the mechanical vigilance of the body when exposed to fore-aft and lateral vibration.

Motion Sickness Simulator studies have systematically explored the effects of the frequency of lateral oscillation (from 0.0315 to 0.2 Hz) on motion sickness and the effects of roll compensation (so as to offset the forces associated with lateral acceleration). These studies have been conducted in the context of tilting trains being introduced in Europe where field trials show that full compensation of lateral acceleration, by tilt of the carriage, increases motion sickness. The results are now being used to develop a predictive model of motion sickness caused by combined lateral acceleration and tilt. Simulator studies with fore-aft and lateral oscillation at low frequency have explored the effects of visual conditions on motion sickness. These studies seek to determine the visual conditions necessary for reducing sickness during low frequency oscillation.

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The Human Factors Research Unit will be participating with eleven other partners in a European contract, ‘A rational approach for reduction of motion sickness and improvement of passenger comfort and safety in sea transportation’ (COMPASS). The main objective is to develop standards for motion sickness and passenger comfort for the future design and operation of passenger vessels, especially high-speed craft. It is planned that the objectives of the proposal will be achieved through mathematical modelling, full-scale trials and laboratory tests. The Human Factors Research Unit will also be participating with eleven partners in another new European contract, ‘Fast and Comfortable Trains’ (FACT). The overall objective of this research includes the development of procedures for using tilting train technology to which maximise performance whilst avoiding the onset of nausea. The Human Factors Research Unit will assist with the design and analysis of field trials and will be responsible for the conduct of laboratory investigations.

HVLab For the detection of the hand-arm vibration syndrome, the Human Factors Research Unit has developed a suite of HVLab diagnostic systems for measuring vibrotactile thresholds, thermotactile thresholds, finger re-warming following cold provocation and finger systolic blood pressures following cooling (with a unique multi-channel plethysmograph). This system is in widespread use within the UK and also in some other countries. In addition, HVLab data acquisition and signal analysis software is available for the evaluation of exposures to whole-body vibration and hand-transmitted vibration, the control of laboratory simulators and the analysis of other time varying signals (e.g. physiological measurements).

Services The Human Factors Research Unit provides services related to all aspects of human exposure to vibration. Evaluations are made of the vibration on powered hand tools at workplaces so as to assist industry or the courts in the assessment of tool safety. Laboratory services include testing the dynamic performance of vehicle seats (both conventional seats and suspension seats), gloves and hand-held vibratory tools. Evaluations are made of whole-body vibration occurring in vehicles with respect to both safety and vehicle ride comfort. Objective assessments are undertaken for the signs of disorder in persons with symptoms of injury caused by hand-transmitted vibration. Clinical assessments of patients at risk of developing disorders associated with exposure to hand-transmitted vibration are also undertaken.

The HVLab multi-channel plethysmograph being used to measure finger blood flow and finger systolic blood pressure on five fingers simultaneously

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Assessing balance using computerised posturography


3.1 Hearing Aids and Cochlear Implants 3.1.1 Evaluation of benefits from signal processing hearing aids, middle-ear and cochlear implants

(M E Lutman, E Payne, M L Grasmeder; S A Wood [MRC Institute of Hearing Research, Nottingham]; H E Cullington; A Leijon, M Dahlquist [KTH, Stockholm]; A Garcia [CNAM, Paris]; J Boudy, P Lockwood [Matra Nortel, Paris]; P Balsiger [IMT, Neuchatel, Switzerland]; H Bächler, S Launer, P Derleth [Phonak, Stäfa, Switzerland])

3.1.2 Investigation of acclimatisation to amplified speech and plasticity of the auditory central nervous system (K J Munro)

3.1.3 Development of preverbal and verbal communication skills in children with hearing aids and cochlear implants (M E Lutman, S C Paganga, E R Tucker; M Tait [Nottingham Paediatric Cochlear Implant Programme])

3.1.4 Acoustic transfer functions relating hearing aid output to sound pressure at the tympanic membrane and responses to sound (K J Munro; R Seewald [University of Western Ontario])

3.1.5 Evaluation of outcomes following cochlear implantation in adults and children (M E Lutman, J A Eyles, J C Brinton, M L Grasmeder, C A Verschuur; S M Archbold, G M O’Donoghue, T Nikolopoulos [Nottingham Paediatric Cochlear Implant Programme]; S Gregory [Ear Foundation, Nottingham])

3.1.6 Electrophysiological investigations of cochlear implants (M L Grasmeder, R A Ricaud, H E Cullington)

3.1.7 Benefits of external listening devices used with hearing aids and cochlear implants (E J Wood, S L Flynn)

3.1.8 Early identification of candidates for hearing aids (M E Lutman, E Payne; A C Davis [MRC Institute of Hearing Research, Nottingham])

3.1.9 Studies of music perception in normal listeners and patients with cochlear implants (M L Grasmeder, M E Lutman)

3.2 Cochlear Function 3.2.1 Development of recording and analysis techniques for otoacoustic emissions and evoked potentials

(M E Lutman, S Kapadia, S L Bell, N Thomas; B Lineton [MRC Institute of Hearing Research, Southampton])

3.2.2 Investigation of non-linearities in the human auditory system (M E Lutman, S Kapadia; A J Hall [Institute of Child Health, Bristol]; N Thomas; B Lineton [MRC Institute of Hearing Research, Southampton])

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3.2.3 Novel methods for monitoring hearing and early identification of sensorineural hearing loss (M E Lutman; A J Hall [Institute of Child Health, Bristol])

3.2.4 Investigation of active mechanisms in the cochlea and their relation to hearing sensitivity (M E Lutman, S Kapadia; A J Hall [Institute of Child Health, Bristol])

3.2.5 Modelling of otoacoustic emission generation and properties (M E Lutman, S Kapadia; B Lineton [MRC Institute of Hearing Research, Southampton])

3.2.6 Investigation of dead regions in the human cochlea (S Kapadia, K J Munro, M E Lutman; B C J Moore [Department of Experimental Psychology, Cambridge University])

3.3 Vestibular Function 3.3.1 Health-related quality of life and balance disorders (R L Booth [Royal Berkshire Hospital, Reading];

M E Lutman, A E Morris; L Yardley [Department of Psychology]) 3.3.2 Recovery of function, quality of life and needs for rehabilitation services following acoustic neuroma

surgery (J Burgneay, M E Lutman; H C Martin [Boots, Nottingham]; S Rayner [Royal South Hants Hospital, Southampton])

3.3.3 Studies of computerised dynamic posturography (J Burgneay; G Neil-Dwyer, D Lang [Wessex Neurology Centre, Southampton]; A Davis [Queen Alexandra Hospital, Portsmouth])

3.3.4 Balance problems in patients with cochlear implants (J Burgneay)

3.4 Noise-induced Hearing Loss and other Audiological Projects 3.4.1 Studies of underwater hearing mechanisms (E Johnston, M E Lutman, A M Martin) 3.4.2 Quantification of occupational noise exposure from communication headsets and insert earphones

(B W Lawton) 3.4.3 Effects of recreational sound and music on hearing (M E Lutman, M C Lower, B W Lawton;

A C Davis, M A Ferguson [MRC Institute of Hearing Research, Nottingham]) 3.4.4 Standards for normal hearing and audiological instruments (B W Lawton, M E Lutman; A C Davis,

P A Smith [MRC Institute of Hearing Research, Nottingham]) 3.4.5 Evaluation of damage risk criteria for hearing conservation purposes (B W Lawton) 3.4.6 Interaction between noise-induced and age-associated hearing loss (M E Lutman; A C Davis

[MRC Institute of Hearing Research, Nottingham]) 3.4.7 Ototoxicity of volatile organic chemicals (B W Lawton)

3.5 Subjective Acoustics 3.5.1 Aircraft Noise Attitudes Study (S Lowe, G Terzis, P LeMasurier, J Bates, M Dix, P Evans, N Porter

[MVA Consultancy and others]; I H Flindell) 3.5.2 Speech masking by delayed reinforcement (K Vivatvakin, I H Flindell) 3.5.3 Noise mapping uncertainties (J Alberola, A Bullmore [Hoare Lea Acoustics]; I H Flindell) 3.5.4 Airport Noise Complaints analysis (L Solanes Serrano [University of Valencia]; N Arndt [University

of Dortmund]; I H Flindell) 3.5.5 Vehicle impulsive noise assessment (L Gredmaier, I H Flindell) 3.5.6 Noise and health research methodology (J Cartwright, D Humpheson, K Sixsmith [Royal Air Force];

I H Flindell) 3.5.7 Understanding noise annoyance (C Skinner [Building Research Establishment]; I H Flindell)

3.6 Human Factors 3.6.1 Discomfort caused by fore-aft whole-body vibration (F A Price, Y Q Qiu, M Morioka, M J Griffin) 3.6.2 Psychophysical perception of vibration at the hand and foot (M Morioka, M J Griffin) 3.6.3 Driver response to tip-in motion in cars (Y Q Qiu, F A Price, M Morioka, M J Griffin) 3.6.4 Effects of phase on responses to whole-body vibration (Y Matsumoto [Saitama University, Japan];

M J Griffin) 3.6.5 Dynamic modelling of whole-body apparent mass (N Nawayseh) 3.6.6 Factors affecting apparent mass of the human body exposed to vertical vibration (M G R Toward,

M J Griffin) 3.6.7 Biodynamic responses of standing and seated persons exposed to vertical vibration (Y Matsumoto

[Saitama University, Japan]; M J Griffin) 3.6.8 Seat and body dynamics with fore-aft vibration (N A Abdul Jalil, M J Griffin) 3.6.9 The use of multiple-input single output methods to quantify seat transmissibility (Y Q Qiu, M J Griffin)

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3.6.10 Anthropodynamic dummy for measuring seat transmissibility (C H Lewis, M G R Toward, H V C Howarth, M J Griffin)

3.6.11 End-stop impacts in suspension seats (T Gunston, C H Lewis, M J Griffin) 3.6.12 Dynamic modelling of postural stability (D Gong, M J Griffin) 3.6.13 Influence of vision on motion sickness in cars (C A Butler, H V C Howarth, M J Griffin) 3.6.14 Motion sickness caused by combined lateral and roll motion in high speed trains (B L Lobb, M J Griffin) 3.6.15 Neurological responses to hand-transmitted vibration (D Whitehouse, M Morioka, M J Griffin) 3.6.16 Vascular responses to hand-transmitted vibration (A J L Welsh, M J Griffin) 3.6.17 Effects of acute exposures to hand-transmitted vibration on finger blood flow (M Bovenzi [University of

Trieste]; A J L Welsh, M J Griffin) 3.6.18 Effects of gloves on the transmission of vibration to the hand and fingers (M O’Boyle, M J Griffin) 3.6.19 EU Vibration Injury Network (M J Griffin, C H Lewis) 3.6.20 HVLab diagnostic systems (C H Lewis, D Whitehouse, A J L Welsh, M J Griffin) 3.6.21 Literature collection on human responses to vibration (J Griffin, M J Griffin)

Publications Brinton, J.C. Device choice for cochlear implant patients. Medel Co. Workshop, Austria, 2001, Poster Presentation. Measuring language development in deaf children with cochlear implants. International Journal of Language & Communication, 36, 2001, 121-5 supplement. Brinton, J.C., *Topping, J. and Eyles, J. Evaluation of the post implant quality of life questionnaire reliability, validity and application. Abstracts of the First International Adult Aural Rehabilitation Conference, Portland Maine, USA, May 2001, 73. Cullington, H. Light eye colour linked to deafness after meningitis. British Medical Journal, 322, 2001, 587-8. Tinnitus evoked by finger movement: Brain plasticity after peripheral deafferentation. Neurology, 56, 2001, 978-9. Griffin, M.J. The validation of biodynamic models. Clinical Biomechanics, 16(1), 2001, S81-92. Whole-body vibration. In: Braun, S. ed. Encyclopaedia of Vibration, London, Academic Press, 2001, 1570-8. Motion sickness. In: Braun, S. ed. Encyclopaedia of Vibration, London, Academic Press, 2001, 856-61. Hand-transmitted vibration. In: Braun, S. ed. Encyclopaedia of Vibration, London, Academic Press, 2001, 621-9. Griffin, M.J., *Bovenzi, M. and *Nelson, C.M. A consideration of dose-response relationships for vibration-induced white finger. Paper Presented at the X2001 – Exposure Assessment in Epidemiology and Practice, Sweden, 10-13 June 2001, 284-6. *Bovenzi, M., *Lindsell, C.J. and Griffin, M.J. Response of finger circulation to energy equivalent combinations of magnitude and duration of vibration. Occupational and Environmental Medicine, 58(3), 2001, 185-93. *Ebe, K.E. and Griffin, M.J. Factors affecting static seat cushion comfort. Ergonomics, 44(10), 2001, 901-21. *Haward, B.H., Lewis, C.H. and Griffin, M.J. Crew response to motions of an offshore oil production and storage vessel. Human Factors in Ship Design and Operation Conference, London, UK, 27-29 September 2000, 15pp. *Holmes, S.R. and Griffin, M.J. Correlation between heart rate and the severity of motion sickness caused by optokinetic stimulation. Journal of Psychophysiology, 15, 2001, 35-42.

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*Lindsell, C. and Griffin, M.J. Interpretation of the finger skin temperature response to cold provocation. International Archives of Occupational and Environmental Health, 74, 2001, 325-35. *Matsumoto, Y. and Griffin, M.J. Modelling the dynamic mechanisms associated with the principal resonance of the seated human body. Clinical Biomechanics, 16(1), 2001, 31-44. *Paddan, G.S. and Griffin, M.J. Use of seating to control exposures to whole-body vibration, Health & Safety Executive Contract Research Report 355/2001, London, Health & Safety Executive, 2001, 131pp. Measurement of glove and hand dynamics using knuckle vibration. 9th International Conference on Hand-Arm Vibration, Nancy, France, 5-8 June 2001, 2pp. *Palmer, K.T., *Coggon, D., *Syddall, H., *Pannett, B., and Griffin, M.J. Occupational exposures to noise and hearing difficulties in Great Britain, Health & Safety Executive Contract Research Report 361/2001. London, Health & Safety Executive, 2001, 61pp. *Palmer, K.T., Griffin, M.J., *Syddall, H.E., *Pannett, B., and *Coggon, D. Occupational exposure to noise and the attributable burden of hearing difficulties in Great Britain. EPIOCH 2001, Fifteenth Symposium in Epidemiology in Occupational Health Work and Health the Role of Epidemiology, Copenhagen, Denmark, 20-22 August 2001, 1. Raynaud's phenomenon, vibration-induced white finger, and difficulties in hearing. EPIOCH 2001, Fifteenth Symposium in Epidemiology in Occupational Health Work and Health the Role of Epidemiology, Copenhagen, Denmark, 20-22 August 2001, 1. *Palmer, K.T., Griffin, M.J., *Syddall, H.E., *Pannett, B., *Cooper, C. and *Coggon, D. Risk of hand-arm vibration syndrome according to occupation and sources of exposure to hand-transmitted vibration: A national survey. American Journal of Industrial Medicine, 39, 2001, 389-96. Exposure to hand-transmitted vibration and pain in the neck and upper limbs. Occupational Medicine, 51(7), 2001, 464-7. *Palmer, K.T., *Walker-Bone, K., Griffin, M.J., *Syddall, H., *Pannett, B., *Cooper, C. and *Coggon, D. Prevalence and occupational associations of neck pain in the British population. Scand J Work Environ Health, 27(1), 2001, 49-56. *Pinto, I., *Stacchini, N., *Bovenzi, M., *Paddan, G.S. and Griffin, M.J. Protection effectiveness of anti-vibration gloves: Field evaluation and laboratory performance assessment. 9th International Conference on Hand-Arm Vibration, Nancy, France, 5-8 June 2001, 2pp. *Quetin, F., *Clement, P., Griffin, M.J. and Lobb, B.L. Studies about motion sickness, effect of combine lateral and roll oscillations. World Congress in Railway Research Conference, Köln, Germany, 25-29 November 2001, 11pp. *Seidel, H. and Griffin, M.J. Modelling the response of the spinal system to whole-body vibration and repeated shock. Clinical Biomechanics, 16(1), 2001, 3-7. Gunston, T.P. A method of estimating the damper characteristics for a suspension seat dynamic model. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 116-26. Howarth, H.V.C. A comparison of motion sickness with 2-dimensional and 3-dimensional visual scenes. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 399-409. Kapadia, S. and Lutman, M.E. Static input-output nonlinearity as the source of nonlinear effects in maximum length sequence click-evoked otoacoustic emissions. British Journal of Audiology, 35(1), 2001, 103-12.

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Lawton, B.W. Damage to human hearing by airborne sound of very high frequency or ultrasonic frequency, Health & Safety Executive Contract Research Report 343/2001, London, Health & Safety Executive, 2001, 83pp. A noise exposure threshold level for hearing conversation, Report No. 01/52, CONCAWE, Brussels, 2001, 26pp. Lewis, C.H. An adaptive electro-mechanical model for simulating the driving point force response of the human body with different input motions. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 307-21. Lobb, B. A frequency weighting for motion sickness susceptibility in the lateral axis. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 386-98. *Marriage, J., *King, J., *Briggs, J. and Lutman, M.E. The reliability of the SCAN test: Results from a primary school population in the UK. British Journal of Audiology, 35, 2001, 199-208. *Martin, H.C., *Sethi, J., *Lang, D., *Neil-Dwyer, G., Lutman, M.E. and *Yardley, L.J. Patient-assessed outcomes after excision of acoustic neuroma: Post-operative symptoms and quality of life. Journal of Neurosurgery, 94, 2001, 211-16. *Tait, M., Lutman, M.E. and *Nikolopoulos, T.P. Communication development in young deaf children: Review of the video analysis method. International Journal of Paediatric Otorhinolaryngology, 61, 2001, 105-12. Morioka, M. Sensitivity of pacinian and non-pacinian receptors: Effect of surround and contact location. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 266-76. Morioka, M. and Griffin, M.J. Effect of vibration frequency and contact area on sensation magnitudes for hand-transmitted vibration. 9th International Conference on Hand-Arm Vibration, Nancy, France, 5-8 June 2001, 2pp. Munro, K.J. Individually measured acoustic transforms and their application with young children. Belgium Society of Audiology Annual Conference, Belgium, 2001, 1p. Implications for audiometry and hearing instrument selection in young children. Second Workshop on Hearing Aid Selection and Fitting in Young Children, St Michielgestel, Holland, 2001, 1p. Munro, K.J. and *Davis, J. A comparison of real-ear SPL measured directly during in-situ audiometry and derived indirectly using customised acoustic transformations. A Sound Foundation through Early Amplification, Chicago, USA, 2001, 1p. Munro, K.J. and *Lazenby, A. Using the real-ear to dial difference acoustic transform to derive real-ear sound pressure level for audiometric data obtained with the ER-3A insert earphone. British Journal of Audiology, 35, 2001, 297-306. Munro, K.J. and Lutman, M.E. Acclimatisation to amplified speech: The importance of presentation level. British Society of Audiology Annual Conference, Winchester, UK, 2001, 1p. Munro, K.J. and *Salisbury, V.A. Does it matter which transducer is used when measuring the RECD? A Sound Foundation through Early Amplification, Chicago, USA, 2001, 1p. Munro, K.J., *Killen, T. and *Moore, B.C.J. Diagnosing dead regions in the cochlea of teenagers with a severe-to-profound hearing impairment. British Society of Audiology Annual Conference, Winchester, UK, 2001, 1p.

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*Martin, H.C., Munro, K.J. and *Lam, M.C. Perforation of the tympanic membrane and its effect on the RECD acoustic transform function. British Journal of Audiology, 35, 2001, 259-64. Nawayseh, N. The non-linear behaviour and the two dimensional movement of the human body in response to vibration. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 288-96. O'Boyle, M.O. The effect of hand and arm volume on the transmissibility of gloves according to current standards. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 359-67. O'Boyle, M.O. and Griffin, M.J. Inter-subject variability in the measurement of the vibration transmissibility of gloves according to current standards. 9th International Conference on Hand-Arm Vibration, Nancy, France, 5-8 June 2001, 2001, 2pp. Paganga, S., Tucker, E., *Harrigan, S. and Lutman, M. Evaluating training courses for parents of children with cochlear implants. International Journal of Language and Communication Disorders, 36, Supplement 2001, 517-22. Payne, E. Review of Christensen, L.A. and Northern, J.L. Speech intelligibility in noise with hearing aids. In: ENT News, 10(3), 2001, 103. Qiu, Y. Measurement of seat transmissibility for fore-aft vibration. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 86-96. Qiu, Y, *Crisfield, M.A., and *Alfano, G. An interface element formulation for the simulation of delamination with buckling. Engineering Fracture Mechanics, 68, 2001, 1755-76. Toward, M.G.R. Effect of backrest interaction on seat cushion transmissibility. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 106-15. Verschuur, C.A. and Rafaely, B. An exploratory study into perception of acoustic speech cues by hearing-impaired adults. British Journal of Audiology, 35, 2001, 209-17. Welsh, L.J.L. Comparison between two venous occlusion plethysmographs for finger blood flow measurement. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 11-24. Welsh, L.J.L. and Griffin, M.J. Comparison of alternative equipment for measuring finger blood flow. 9th International Conference on Hand-Arm Vibration, Nancy, France, 5-8 June 2001, 2pp. Whitehouse, D. The effect of contact location and probe size on vibrotactile thresholds at the fingertip. 36th UK Group Conference on Human Response to Vibration, Farnborough, UK, 12-14 September 2001, 1-10. Whitehouse, D., *Lundström, R. and Griffin, M.J. Comparison of vibrotactile and thermal thresholds with two different measurement systems. 9th International Conference on Hand-Arm Vibration, Nancy, France, 5-8 June 2001, 2pp. Wood, E.J. and Cross, S.E. Audiology Refresher No. 19 checking cochlear implants. BATOD Magazine, November/December 2001, 39.

* - Not working in ISVR

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1.4 Signal Processing and Control Group Group Chairman: Professor S J Elliot

Group Developments It is a great pleasure to report the promotion of Dr Boaz Rafaely to a Senior Lectureship. He has made substantial contributions to both teaching and research, but has also carried a considerable administrative load in steering the Applied Digital Signal Processing (ADSP) MSc course through its first few years. The first annual review of the European Doctorate in Sound and Vibration Studies (EDSVS) was held in Ferrara in October, chaired by Dr Gardonio. Most partners had received some students by then, with the ISVR having hosted exactly the number in the original plan. The EDSVS has been developed with EU funding under the Marie Curie training scheme and the intention is to extend this activity within the new Framework 6 programme, both under the Marie Curie scheme and as a training component in both the Networks of Excellence and Integrated Projects with which the ISVR will be involved. A major development this year has been the launch of the Masters Level Training Packages in Biomedical Signal Processing in collaboration with the Human Sciences Group, supported by the EPSRC. Dr David Simpson has been appointed Lecturer in Biomedical Signal Processing and Dr Antonio De Stefano has been appointed as Distance Learning Co-ordinator. At the time of writing (June 2002) one module has been delivered and several others are in preparation with two more being offered later this year. The distance learning aspects of the packages are very important for support of those who have attended the modules and have returned to their hospitals or companies, and considerable emphasis is placed on this during module development. Visitors have included Sara Van Der Hoeven working with Professor Elliott on active control; Professor Bai working with Professor Elliott on control algorithms; Pascal Augereau, working with Dr Maury on sound transmission from active control of turbulent boundary layer noise; Alexis Deltour, working with Dr White on tactile biometrics; Dr Shunsuke Ishimitsu, working with Professor Elliott on active control algorithms; Alberto Cannizzaro, working on horn loudspeakers with Dr Gardonio, and Dr Brennan of the Dynamics Group; and Dr Nicole Kessissoglou, working with Dr Gardonio on active vibration isolation. Those joining the group include Dr Zhenping Feng, working with Professor Allen on underwater vehicles, Torbjörn Johansson, working with Dr White on the sounds of underwater mammals and Dr Husam Abulula, working with Professor Elliott on the silent seat project. Dr Teresa Bravo, who has rejoined the group after completing her PhD in Madrid having obtained an individual Fellowship under the EU Marie Curie scheme, will be working with Professor Elliott and Dr Gardonio on the simulation of spatially random pressure fields. Lewis Rees has joined the Group as a PhD student, sponsored by Jaguar Cars to work on active control, together with Luca Benassi, working with Dr Gardonio and Professor Elliott on active vibration isolation. Jonathan Wilcox has returned to the ISVR to undertake a PhD on image processing with Dr White in collaboration with Dr Bill Collis. Dr Andy Tseng has returned to Taiwan to take up an assistant professorship and Dr Jong-Soo Seo has left for a government job in South Korea.

Group Activities Professor Allen completed his year as Chair of AIME (The Association of Institutions Concerned with Medical Engineering) at the end of May. AIME co-ordinates activities across eight professional institutions and has representation from the ABHI (The Association of Healthcare Industries). He has also completed a year in the Royal Academy of Engineering UK Focus Group for Biomedical Engineering. Professor Allen presented a seminar on the Masters Training Package in Biomedical Signal Processing at the Mathworks Workshop on Teaching with Matlab and Simulink held in Southampton in April. Professor Elliott has given invited talks at the Institute of Acoustics in Madrid, as part of its centennial celebrations, and seminars to the Control Department at ETH Zurich, a joint Control Group Seminar and Mechanics Colloquium at Cambridge University, and a talk at the inaugural meeting of the Advanced Control Technology Club Special Interest Group in Automotive Control. Dr Gardonio has presented several courses on the Fundamentals of Vibration at the University of Ferrara in Italy.

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Preparations are well in hand for the ACTIVE2002 conference, which will be held at the University in July.

Research

Active Vibration Control This year has seen significant developments in the active isolation systems being investigated under EPSRC sponsorship. On the theoretical side, a mobility analysis has been used to investigate the stability of active isolation systems, which feed back either absolute velocity or integrated transmitted force. The two control strategies are completely equivalent if the equipment being isolated acts as a rigid body, but will behave rather differently if the frequencies at which the equipment becomes resonant fall within the bandwidth of the controller. Integrated force feedback is a more stable strategy under the most general conditions, but absolute velocity feedback, which implements ‘skyhook damping’, can be shown to be unconditionally stable under a set of conditions which is satisfied in many practical applications. Absolute velocity feedback, if stable, has the advantage that its performance in suppressing the transmitted vibration is superior to that of integrated force feedback. Two experimental arrangements have been investigated. The first is a modification of an earlier experiment with a flexible base plate and an effectively rigid equipment structure supported by four active mounts. The modified equipment structure takes the form of a plate which has flexural modes at the frequencies of control. A photograph of the new experiment is shown below. A theoretical model of this arrangement has been constructed which predicts the measured response very well. Good agreement is also found between the eigenvalues of the predicted and measured matrices of responses between the actuators and sensors, which are important in determining the stability of the multi-channel feedback control system. The control system consists of four independent feedback loops and gives attenuations in the transmitted vibration of up to 30 dB at the main mounted resonances and between 10 and 20 dB at the dominant base and equipment resonance frequencies. The limits of stability have been shown to be set by the phase shifts in the transducer conditioning amplifiers, rather than any fundamental structural effect.

Four channel active vibration isolation system The second experimental arrangement, designed by Dr M J Brennan, has been made as a portable demonstrator. Its construction emphasises the modular nature of the active mounts, each of which has an integrated electromagnetic shaker, a microelectro-mechanical systems (MEMS) accelerometer, and a local feedback control group. Instead of integrating the electromagnetic actuator within the passive mounts, another strategy would be to use inertial electromagnetic devices, which could then operate independently. The problem with using such inertial actuators in a feedback system is that the considerable phase shift in the frequency response at their natural frequency tends to destabilise the system. It has been found that these destabilising effects can be reduced if the

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natural frequency of the actuator is well below the natural frequencies of the system under control, and if the actuator is well damped. These requirements are difficult to meet in practice because of the static motion of the inertial mass and the problem of damping its motion at very low frequencies. Recent work on using local feedback control within the actuator to improve its frequency response prior to its use in an outer feedback loop shows promising results.

Active Vibroacoustic Control Low frequency airborne sound transmission through a panel can be attenuated by using various active control systems, the most attractive of which have the actuators and sensors integrated into the structure to create a ‘smart panel’. The control system linking the actuators to the sensors increasingly uses a feedback rather than feedforward arrangement, because of its ability to deal with broadband random or transient disturbances without an external reference signal. The three key issues which thus face the designer of such a smart panel are: the authority of the integrated actuators to control the disturbance; the ability of the integrated sensors to measure the radiated sound; and the performance of a feedback controller operating on the plant response between these actuators and sensors. The active control effectiveness of ideal volume velocity-uniform force single-channel (SISO) feedback control has been compared with those of three other SISO feedback control systems: first, that using two distributed PVDF transducers with quadratically shaped electrodes (one working as a sensor and the other as an actuator); second, using a 4 × 4 grid of accelerometers for the sensor and a PVDF transducer with quadratically shaped electrode for the actuator and third, a 4 × 4 grid of accelerometers for the sensor and a 4 × 4 grid of PZT quadrilateral small patches for the actuator. In principle, the smart panel with the two piezoelectric transducers with quadratically shaped electrodes offers the best control solution. In practice, the implementation of direct velocity feedback control with such a sensor-actuator transducers does not give an unconditionally stable system because of the coupling between the sensor and actuator transducers via in-plane vibrations of the panel. The other two practical configurations are not affected by this problem but they still have some control limitations due to spatial aliasing of the sensor and actuation control spillover. A multi-channel (MIMO) control system using a 4 × 4 grid of accelerometer sensors and a 4 × 4 grid of piezoelectric patch actuators has also been studied. Previous work has shown that the performance of a decentralised set of local control loops is similar to that of a fully coupled feedback controller. The preliminary studies carried out during the past year have shown that this type of smart panel can offer good control performance with only relatively minor problems of control stability and control spillover. The photograph below shows such a system applied to a panel.

Smart panel with 4 × 4 piezoceramic actuators and 4 × 4 accelerometers

Signal Processing for Hearing Aids and Audio Systems Adaptive feedback cancellation in hearing aids has been studied in two projects. In the first, an acoustic model of the feedback path has been developed using the software packages ‘Matlab’ and ‘Spice’, which generates the

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frequency response of the feedback path under various acoustic conditions and transducers, including a slit leak in the hearing aid fit to the ear. The model has been integrated into an adaptive feedback cancellation scheme by varying the parameters of the model directly using a steepest descent optimisation, and then generating an FIR filter using inverse Fourier transformation. Direct adaptation of the physical parameters, such as vent or leak dimensions, has shown the potential of a significantly faster convergence compared with conventional adaptation schemes such as the normalised LMS algorithms that adapt the coefficients of the system’s impulse response. Current work is focused on the adaptation of a larger number of parameters and improvements in the physical model. In the second project, indirect methods of system identification for adaptive feedback cancellation in hearing aids have been investigated. The potential benefit of indirect identification methods is the reduced bias in the identification of the feedback path compared with current direct methods. This could lead to improved modelling and better feedback cancellation. However, the indirect methods tend to converge more slowly than the direct methods and so techniques to improve convergence speed have been developed. Current research involves the study of the new feedback cancellation methods using realistic hearing aid simulations. A study involving in-ear audio has investigated the enhancement of the speech signal detected by a vibration transducer when placed on the user’s ear or head. These vibration microphones are used for communication in noisy environments due to the low sensitivity to external noise. However, the quality of speech detected by the transducers is poor due to the unnatural path of the speech signal. Enhancement of these signals using optimal filtering has been investigated and the results have shown improvements over conventional high-pass filtering methods. This has now been verified in a comprehensive subjective experiment. Current work involves further analysis of the experimental results with normal recordings and optimally enhanced recordings, and the potential of these enhancement methods to improve speech quality in practice. Adaptive filters which can employ frequency-domain constraints have been studied in another project. A new frequency-domain adaptive algorithm has been developed which can incorporate frequency domain constraints and has improved convergence due to the use of conjugate gradient adaptation. The algorithm has been studied in the application of adaptive audio equalisation, where it showed potential to improve spatial robustness of the equalisation while tracking changes in the response of the electroacoustic system.

Biomedical Signal Processing and Control Several new projects have begun this year with the arrival of new staff, and many projects continue from previous years. One of the latter concerns epilepsy, which is a relatively common neurological disorder that may affect one in twenty of the population at some point in their lives. The reliable prediction of an epileptic seizure would provide an important early-warning signal to patients at risk and may ultimately help in control of the problem. Research continues on the prediction of seizures using both linear and non-linear signal processing and analysis, and results from EEG recording from depth electrodes positioned in the hippocampus of patients with temporal lobe epilepsy are encouraging. In particular, an efficient method of estimating signal complexity with a high temporal resolution has been developed based upon non-linear dynamic analysis. This should help to maximize the potential to detect short-term changes in the signal which may provide a valuable clinical indicator of an impending seizure. Evaluation of the automatic system for classifying heart sounds continues with colleagues in Paediatrics and Cardiology at Southampton General Hospital. Telemedicine techniques continue to develop and allow a trained physician to assess heart sound data collected from a remote location using the automated classification system as an aid to clinical diagnosis. In addition, hidden Markov models are being used to model various cardio-vascular signals in order to segment time series data to enhance the robustness of the heart sound classification system. It is anticipated that the techniques developed during this work will have application to other biomedical signals. Collaborative work with colleagues in the Hearing and Balance Centre continues to develop efficient ways of stimulating the auditory system as a basis for clinically producing the auditory evoked potential (or AEP). This has applications in audiology clinics for hearing assessment and components of the AEP have been shown to have potential as an indicator of the level of consciousness under anaesthesia. Stimulation by maximum length sequence chirps has proved very successful in improving signal-to-noise levels and in reducing the time taken to produce the AEP. A clinical trial is currently underway with a colleague in the Department of Anaesthetics, Southampton General Hospital, to assess the technique during cardiac surgery where cooling the patient during

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the operation has a considerable effect on the AEP. Results to date indicate that the new AEP methods have considerable potential for clinical application. Another project which is developing well concerns the use of non-linear identification techniques to characterise otoacoustic emissions (OAEs) from the ear. A block-non-linear model whose elements represent individual features of the mechanism of OAE generation within the cochlea is being investigated. Once the identification method has been validated, the aim is to use specific test signals to estimate the non-linear characteristics of the active components of the hearing mechanism at different frequencies. The control of blood flow in the brain has received extensive interest in the medical literature in recent years. Impairment of the control system has been linked to a number of serious neurological problems, and can lead to permanent brain damage (including stroke) and death. At present there are no reliable methods that can be used in routine clinical practice to investigate the operation of this control system, which involves the complex interaction between changes in blood flow, blood pressure carbon dioxide levels and other physiological variables. Signal processing methods have provided a powerful research tool in this area and work is progressing which focuses on the interaction between constant spontaneous variations in blood pressure and blood flow, using system identification methods. Computationally-intensive statistical methods (Monte Carlo simulations and Bootstrap techniques) are being investigated for this purpose. In parallel, a study of a combination of non-invasive measurements of arterial blood pressure (using finger plethysmography) and cerebral blood flow velocity (using transcranial Doppler ultrasound) with an autoregressive model with an exogenous input (ARX) is proving to have considerable potential as a basis for assessment of autoregulation. A study is currently in progress, in collaboration with colleagues in the Department of Medical Physics, Southampton General Hospital, to evaluate the relative merits of different methods of perturbing the arterial blood pressure as a basis for assessment of the autoregulatory control system. System identification that can deal with the poor quality of many clinical recordings, and which are often interrupted by short periods of signal loss are also being investigated. One example is the use of coherence in the processing of EEG signals. These activities, together with some of the autoregulation studies, involve collaboration with the Leicester Royal Infirmary and the Federal University of Rio de Janeiro, Brazil. Non-linear modelling of muscle dynamics continues as a basis for design of controllers for functional electrical stimulation (FES) cycling by paraplegic subjects. Tests have been carried out to determine the muscle force produced at different pedal crank angles at different levels of stimulation across several neuromuscular channels. A new collaborative project with the School of Health Professions and Rehabilitation Sciences has begun to develop signal processing methods for analysing and presenting the electromyography (EMG) activity and associated foot pressure data during gait for assessment of the benefits of Botulinum toxin on gait patterns of children suffering cerebral palsy. From pilot work, telemetric EMG data collection, coupled with time-frequency analysis, shows considerable potential and is under further development for larger clinical trials. Collaborative work with the Department of Electronics and Computer Science continues to develop a method of automating the location of spinal vertebrae in a motion sequence of low-dose x-ray images. The method uses the Hough transform as a basis, but several modifications are being made due to the nature of the images and the identification problem. Edge detection of the vertebrae is now improved through the use of a phase congruency method and spatio-temporal characterisation of spine motion appears increasingly possible. The vertebrae are modelled using Fourier descriptors and this model-based location is showing significant advantages for subsequent kinematic analysis. Studies with a model have shown excellent results and this is currently being expanded to study images from healthy volunteers. It is anticipated that the method will provide an automated method of quantifying spine motion for the diagnosis and treatment of spinal problems which are mechanical in origin. The approach used to analyse spine motion is being extended to study the motion of the knee joint, and in particular of total knee replacement prostheses. Longevity of prostheses stimulates research in this area and prosthesis performance and stability is fundamental to the success of an implant. Image processing techniques will be developed to identify the prosthesis in low-dose, motion-ray sequences and these will be combined with ground reaction force data measured as the patient climbs a small staircase. The work is in collaboration with the School of Engineering Sciences and the Department of Trauma and Orthopaedic Surgery, Southampton.

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Underwater Signal Processing There are many unsolved problems in the classification of acoustic sources in the ocean. The increased interest in the effects of noise pollution in the marine environment has added impetus to this field. The main areas of concern are the increase in marine engineering/surveying activity along with the development of high intensity military sonars. In order to minimise the impact of such activity on the marine wildlife one needs to be able to monitor local populations, so that mitigating action can be taken when necessary. Acoustic monitoring is a critical tool for identifying local populations of cetaceans. Present work is aimed at developing tools for classifying vocalisations of cetaceans. Currently this is concentrating on the analysis of “whistles” which are modelled as frequency modulated narrowband signals. The application of parametric methods to such data is being explored; specific models under consideration are time-varying auto-regressive models and polynomial phase models. A hierarchical structure for classification is envisaged where sounds are initially detected, then classified into anthropogenic or natural sounds. The anthropogenic sounds being discarded and from the natural sounds cetacean vocalisations are identified and classified into broad classes, e.g. large whales, small dolphins. In principle, these classes can then be further subdivided, although for many monitoring applications this level of classification is sufficient. Methods for acoustic surveying are being developed in conjunction with colleagues at the School of Ocean and Earth Science. One area of study has the goal of using acoustic techniques to determine characterisations of the sea floor sediments. This technique is based on measuring the characteristics of echoes received from the sea floor when a chirped pulse is emitted. By examination of the instantaneous frequency of the echo pulse it is believed that the absorption coefficient of the sediment can be identified; this provides a key parameter in the sea floor classification. This system is to be validated in tidal regions where in situ measurements of the seabed can be made at low tide and the same sediment can be measured at high tide using remote acoustic techniques. Additional collaborative work has been undertaken to develop a system for constructing high-resolution subsurface profiles, for applications including marine archaeology. A critical aspect of this work is the design of the transducer array geometry to ensure that a suitable transducer beam-pattern is obtained. Further work on post-processing algorithms will be undertaken once the system has undergone its trials phase. Work has continued on the development of a correlation velocity log (CVL), designed to provide high quality velocity information for autonomous underwater vehicles (AUVs). The principle on which a CVL is based is that two acoustic signals are emitted, with a preset time delay. The echoes from these two signals are then received across a spatially diverse array. Using cross-correlations one can then infer the sensor’s motion during the interval between the pings and hence estimate the sensor platform’s velocity. To achieve the required velocity estimates one needs to locate the peak of the measured spatial correlation function with accuracy greater than that provided by the sensor positions. Algorithms to achieve this goal have been developed using the principles of Maximum Likelihood (ML) and Least Squares (LS). The performance of these algorithms has been tested using a simulation environment developed previously. The ML algorithm has been shown to achieve better performance in the majority of instances; however it is based on an iterative procedure that is prone to very occasional divergence. Hence, a rule-based combination of the two methods has been developed whose performance is robust and realises a performance that is close to optimal. The estimation of oceanic bubble populations provides important information both for oceanographic models and sonar performance evaluations. There are two broad classes of measurement schemes: active methods that provide an accurate measure of bubble density per unit volume, but which only interrogate a small volume; and passive methods, which conventionally measure bubble distributions in a greater volume, but provide information about absolute bubble numbers, not bubble density. Recent work has considered the problem of developing passive bubble counting algorithms that provide density measures over much greater volumes than can be achieved using active techniques. These methods are based on using higher order statistics, which have the additional benefit of being robust in the presence of oceanic background noise. A further development in the field of array processing, which may find application in sonar systems, has been the study of methods for computing spatial spectra in a non-stationary environment. These methods extend the principles of time-frequency analysis to the problem of non-stationary spatial spectral estimation. It has been demonstrated that these schemes can be applied to a variety of array geometries and can be used in conjunction with many of the established algorithms for spatial spectrum estimation. One potential drawback of such schemes is the presence of cross terms that hinder the use of conventional time-frequency analysis. These cross

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terms can be shown to represent a significant problem only in a few simple array geometries, and even in those cases, methods have been established that can be successfully employed to mitigate their effect.

Image Processing The field of image processing is an expanding area of research. The main issue under consideration is that of segmentation video sequences which involves the division of an image sequence into individual objects. Image segmentation can be conducted in either an unsupervised or supervised mode. Projects in both contexts are ongoing. The problem of segmentation of single images has been widely considered; this work focuses on the segmentation of a sequence of images. Such a video segmentation can occur on-line (by segmenting the current image on the basis of only passed images) or off-line (by assuming that the complete video sequence is available). Unsupervised video segmentation provides a low level tool that can be used to enhance the performance of other image processing algorithms. For example, a successful segmentation tool can be used to provide information to an image coding scheme which can significantly improve the performance of the coder. Current work has explored the application of morphological operators, that form the basis of several image segmentation schemes, to video sequences. Algorithms that extend concepts defined for individual images have been extended to sequences and shown to achieve good performance. The problem of segmenting complete video sequences has also been considered, specifically in the context of post-production. The goal is to provide the film and TV industry with tools for extracting objects from one video sequence and then inserting them into a second sequence (a task that at present is most commonly achieved using green/blue screen technology). Such a segmentation requires the user to initially identify the object to be extracted and then to track that sequence through successive frames. The basis of the methods being explored is statistical and exploits a Bayesian framework for the problem.

Non-Stationary Processes Research is coming to an end on transcription of polyphonic music. The aim has been to recognise the notes present in a musical chord (played on a piano) possibly having notes with coincident harmonics. The approach used is based on the Karhunen-Loève expansion (KLE) in which the piano notes are modelled as non-stationary stochastic transients. Singular value decomposition (SVD) is also used in place of the KLE for ease of implementation. Based on the SVD technique we proposed a recognition process for piano signals. This method uses a priori data of each piano note that is decomposed using SVD. The singular vectors, of the resulting decomposition of each note forming a set of orthonormal vectors, are the reference for the identification of future piano events. The first singular vectors of real piano notes are very similar to a possible event of a single note and the recognition of single notes is performed accurately. The measure of the presence of a note in a piano signal is given by the Euclidean norm of the projection of that note in the subspace defined by the singular vectors of the single piano notes. It is possible to detect the octaves. The recognition of the notes in a chord is more difficult but considerable success has been achieved.

System Identification Principal Component Analysis (PCA) has been investigated as a method for identification of linear relationships between system input and response variables in both the time and frequency domains and has been extended to non-linear systems in which the use of PCA leads to a form of linearisation of the system. The relative strengths (eigenvalues of the appropriate correlation matrix) of the principal components directly indicate the significance of the non-linearity and the equivalent linear system is deduced from the corresponding eigenvectors. This has been applied to the non-linear behaviour of rotating machinery within which impacts occur.


4.1 Active Control 4.1.1 Active control of air-borne and structure-borne sound transmission through double panels

(P Gardonio, S J Elliott, C Maury) 4.1.2 Feedback control of sound radiation (S J Elliott, P Gardonio, E Bianchi) 4.1.3 Control strategies for an active headset (B Rafaely, S J Elliott, M Jones) 4.1.4 Active structural acoustic control (P Gardonio, Y-S Lee, S J Elliott, E Bianchi)

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4.1.5 Active isolation of equipment from base structure vibration (S J Elliott, M J Brennan, X Huang, P Gardonio, L Benassi)

4.1.6 Multi-channel real-time ANC (M Jones, S J Elliott, B Rafaely) 4.1.7 Active headset using vibration control (B Rafaely, J Carrilho, P Gardonio) 4.1.8 Investigation into diffuse sound fields (I Chun, B Rafaely, P F Joseph) 4.1.9 Simulation of TBL pressure fields (S J Elliott, C Maury, P Gardonio) 4.1.10 Distributed sensor-actuators (P Gardonio, Y-S Lee, S J Elliott) 4.1.11 Decentralised feedback ASAC control (E Bianchi, P Gardonio, S J Elliott, M J Brennan) 4.1.12 Decentralised feedback control of sound transmission through window (P Gardonio) 4.1.13 Active headset review (B Rafaely, S J Elliott) 4.1.14 Combined feedback-feedforward active headset (B Rafaely, M Jones)

4.2 Signal Processing for Hearing Aids and Audio Systems 4.2.1 Feedback path modelling in hearing aids (J L Hayes, B Rafaely, M E Lutman) 4.2.2 Adaptive equalisation using constrained adaptation (P S Tam, B Rafaely) 4.2.3 Adaptive feedback cancellation in hearing aids (N A Shusina, B Rafaely) 4.2.4 In-ear speech microphone (K Papanagiotou, B Rafaely; C Shadle [Department of Electronics and

Computer Science]) 4.2.5 Speech enhancement for hearing aids in severe acoustic environments (B Rafaely) 4.2.6 Spatially optimal Wiener filters (B Rafaely) 4.2.7 Adaptive and robust feedback cancellation in hearing aids (B Rafaely, N A Shusina, J L Hayes)

4.3 Underwater Signal Processing 4.3.1 Detection and classification of transients (P R White) 4.3.2 Analysis and modelling of a correlation velocity log (P R White; M Hill [School of Engineering

Sciences]) 4.3.3 Development of a 3-D chirp profiler (P R White, T G Leighton; J Dix, J Bull [School of Ocean and

Earth Science]) 4.3.4 Sediment classification using a chirp profiler (P R White, T G Leighton; J Dix, J Bull [School of

Ocean and Earth Science]) 4.3.5 Robust control of autonomous underwater vehicles (N S Mohd-Saleh, R Allen) 4.3.6 Improving dynamic performance of underwater vehicles (Z Feng, R Allen [and teams at the

Universities of Plymouth and Wales])

4.4 System Modelling and Image Processing 4.4.1 Transcription of polyphonic music (C Carrasco, J K Hammond) 4.4.2 Video image enhancement (A De Stefano, W B Collis, P R White) 4.4.3 The use of non-linear filters for image processing (A Giani, P R White) 4.4.4 Statistical methods for transfer function estimation (M Tan, J K Hammond) 4.4.5 Image segmentation for moving images (O Baumann, P R White) 4.4.6 Sediment classification using a chirp profiler (P R White, T G Leighton; J Dix, J Bull [School of

Ocean and Earth Science])

4.5 Biomedical Signal Processing and Control 4.5.1 Voice modelling (A Barney) 4.5.2 Detection of anatomical landmarks in low-grade medical images (P Bifulco, M Cesarelli [Department

of Biomedical Engineering, University of Naples]; R Allen) 4.5.3 Signal processing techniques for non-invasive assessment of intracranial dynamics (Y Liu, R Allen) 4.5.4 Multimodality monitoring for the intensive care unit (S Powell [Southend Hospital]; R Allen) 4.5.5 Detection and classification of heart murmurs (P R White) 4.5.6 Measurement of bone properties using ultrasonic techniques (E R Hughes, P R White, T G Leighton) 4.5.7 Estimation of the level of consciousness during anaesthesia using auditory evoked potentials (S L Bell,

M Lutman, R Allen) 4.5.8 Control of functional electrical stimulation for paraplegic cycling (N A C Hatcher, S J Elliott, R Allen) 4.5.9 Identification of spinal vertebrae in low-dose, motion x-rays using the Hough Transform (Y Zheng;

M Nixon [Department of Electronics and Computer Science]; R Allen)

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4.5.10 Clinical assessment of spine stability from low-dose, motion x-rays (M Kondracki [Anglo European College of Chiropractic, Bournemouth]; R Allen)

4.5.11 Modelling of cardio-vascular signals using hidden Markov models (E Romero-Vivas, P R White) 4.5.12 Signal processing and control for walking orthoses for paraplegic upright mobility (R Allen;

P Chappell [Department of Electronics and Computer Science]; Universities of Portsmouth and Sheffield, Spinal Unit, Odstock Hospital, Salisbury)

Publications Allen, R. Editor-in-Chief, Medical Engineering & Physics, Elsevier Science Ltd, published weekly commencing with 23(1), 2001. Wheelchair engineering and design (Editorial to Special Issue). Medical Engineering & Physics, 23, 2001, iii-iv. Allen, R. and *Hong, S. Tool wear monitoring using a combination of cutting force and vibration signals. Condition Monitoring and Diagnostic Engineering Management, 4(1), 2001, 26-32. Allen, R. and *Kondracki, M. Passive motion analysis of the lumbar spine in vivo (Invited Lecture). Proceedings of the International Conference on Biomechanics & Annual Scientific Meeting of the Taiwanese Society of Biomechanics, Taipei, Taiwan, 9-11 November 2001, 26. Allen, R. and *Smith, D. Neuro-fuzzy control of the depth of anaesthesia (Invited Author). Artificial Intelligence in Medicine, Special Issue on “Fuzzy Theory in Medicine”, 21(1-3), 2001, 185-91. Allen, R., Zheng, Y. and *Nixon, M.S. Measurement of the kinematics of the lumbar spine in vivo (Invited Keynote Speech). Proceedings of the International Conference on Biomechanics & Annual Scientific Meeting of the Taiwanese Society of Biomechanics, Taipei, Taiwan, 9-11 November 2001, 25. *Bifulco, P., *Cesarelli, M., Allen, R., *Sansone, M. and *Bracale, M. Automatic recognition of vertebral landmarks in fluoroscopic sequences for analysis of intervertebral kinematics. Medical & Biological Engineering & Computing, 39, 2001, 65-75. *Cooper, R., Allen, R. and Cardan, C. Computer visualisation of the moving human spine. Computers in Biology and Medicine, 31, 2001, 451-69. *Powell, S.A., *Hames, T.K. and Allen R. Computerised multi-modality monitoring in a critical care environment. Meeting of the IPEM Advances in Patient Connected Monitoring, Institute of Physics, London, UK, 5 March 2001, 8. Barney, A. and *Shadle, C.H. Aerodynamic and aeroacoustic aspects of vowel production. Comments on Theoretical Biology, 6(1), 2001, 29-54. Bell, S.L., Allen, R. and Lutman, M.E. The feasibility of maximum length sequences to reduce acquisition time of the middle latency response. Journal of the Acoustical Society of America, 109(3), 2001, 1073-81. Bravo, T. and Elliott, S.J. Robust performance analysis on active noise control systems, ISVR Technical Memorandum 875, Southampton, University of Southampton, 2001, 29pp. Carrasco, A.C.P. and Hammond, J.K. Application of Karhunen-Loève expansion to nonstationary signals. Proceedings of the 4th International Conference on Acoustical and Vibratory Surveillance Methods and Diagnostic Techniques, Compiegne, France, 1, 16-18 October 2001, 103-14. Elliott, S.J. Active control of nonlinear systems. Noise Control Engineering Journal, 49(1), 2001, 30-53. Elliott, S.J. and Gardonio, P. Active control of sound transmission. Proceedings of Inter-Noise 2001, The Hague, The Netherlands, 2, 27-30 August 2001, 671-80.

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Elliott, S.J., Gardonio, P. and Maury, C. A feasibility study for the laboratory simulation of turbulent boundary layer pressure fields. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA-2001-2194, 28-30 May 2001, 10pp. Elliott, S.J., *Serrand, M. and Gardonio, P. Feedback stability limits for active isolation systems with reactive and inertial actuators. Transactions of the American Society of Mechanical Engineers – Journal of Vibration and Acoustics, 123, 2001, 250-61. Elliott, S.J., Gardonio, P., *Sors, T.C. and Brennan, M.J. Active vibro-acoustic control with multiple local feedback loops. Proceedings of SPIE, Smart Structures and Materials 2001, Smart Structures and Integrated Systems, Newport Beach, USA, 4327, 2001, 720-31. *Anthony, D.K. and Elliott, S.J. On reducing vibration transmission in a two-dimensional cantilever truss structure using geometric optimization and active vibration control techniques. Journal of the Acoustical Society of America, 110(2), 2001, 1191-4. *Cunefare, K.A., *Currey, M.N., *Johnson, M.E. and Elliott, S.J. The radiation efficiency grouping of free-space acoustic radiation modes. Journal of the Acoustical Society of America, 109(1), 2001, 203-15. Feng, Z. and Allen, R. Modelling of Subzero II, ISVR Technical Memorandum 880, Southampton, University of Southampton, 2001, 19pp. Gardonio, P., Ferguson, N.S. and Fahy, F.J. A modal expansion analysis of noise transmission through circular cylindrical shell structures with blocking masses. Proceedings of the 17th International Congress on Acoustics, Rome, Italy, Session 5A.03.05, 2-7 September 2001, 175. A modal expansion analysis of noise transmission through circular cylindrical shell structures with blocking masses. Journal of Sound and Vibration, 244(2), 2001, 259-97. Gardonio, P., Lee, Y.-S. and Elliott, S.J. Analysis and measurement of a matched volume velocity sensor and uniform force actuator for active structural acoustic control. Journal of the Acoustical Society of America, 110(6), 2001, 3025-31. Gardonio, P., Lee, Y.-S., Elliott, S.J. and *Debost, S. A panel with matched polyvinylidene fluoride volume velocity sensor and uniform force actuator for the active control of sound transmission. Proceedings of the Institute of Mechanical Engineers, Journal of Aerospace Engineering, 215(G), 2001, 187-206. Giani, A., White, P.R., Collis, W.B. and *Weston, M. Exploiting input space symmetries in video deinterlacing using radial basis function networks. Proceedings of the International Conference on Image Processing, Thessaloniki, Greece, September 2001, 536-9. Hammond, J.K. Nonstructural Dynamics. In: Ewins, D.J. and Inman, D.J. eds. Structural Dynamics @ 2000: Current Status and Future Directions, Research Studies Press Ltd, 2001, 49-58. Hammond, J.K. and Waters, T.P. Signal processing for experimental modal analysis. Philosophical Transactions of the Royal Society A, 359(1778), 2001, 41-59. Hatcher, N.A.C., Allen, R., Elliott, S.J. and *Perkins, T.A. An analytical model of a spinal root stimulated neuromuscular system. Proceedings of the 23rd Annual Conference of the IEEE/EMBS, Istanbul, Turkey, Paper 3.5.1.3(898), 25-28 October 2001, 4pp. Hayes, J.L. and Rafaely, B. Modelling the feedback path in hearing aids. Programme and Abstracts of the British Society of Audiology Annual Conference 2001, Winchester, UK, 6-7 September 2001, 3. Parametric adaptation algorithm for feedback cancellation, ISVR Technical Memorandum 871, Southampton, University of Southampton, 2001, 22pp.

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Huang, X., Elliott, S.J. and Brennan, M.J. Active vibration isolation of a flexible equipment structure on a flexible base, ISVR Technical Memorandum 879, Southampton, University of Southampton, 2001, 44pp. Kessissoglou, N.J. Active attenuation of the wave transmission through an L-plate junction. Journal of the Acoustical Society of America, 110, 2001, 267-77. An analytical and experimental investigation on active control of the flexural wave transmission in a simply-supported ribbed plate. Journal of Sound and Vibration, 240, 2001, 73-85. Lee, Y.-S. and Elliott, S.J. Active position control of a flexible smart beam using internal model control. Journal of Sound and Vibration, 242(5), 2001, 767-91. Lee, Y.-S., Elliott, S.J. and Gardonio, P. Distributed four-layer PVDF actuator/sensor arrangement for the control of beam motion. Proceedings of the SPIE 8th Annual International Symposium on Smart Structures and Materials, Newport Beach, California, USA, 4326, 2001, 284-94. Lee, Y.-S., Gardonio, P. and Elliott, S.J. Experimental verification of volume velocity control of a smart panel using quadratically shaped PVDF actuators and accelerometers arrangement. International Conference on Smart Technology Demonstration & Devices, Edinburgh, 12-14 December 2001, CD ROM. Liu, Y., Allen, R., *Kirkham, S. and *Birch, A. Comparison of two linear models of dynamic cerebral autoregulation. Proceedings of the 23rd Annual Conference of the IEEE Engineering in Medicine and Biology Society, Istanbul, Turkey, Paper 1.2.7.5.(1287), 25-28 October 2001, 4pp. Maury, C., Gardonio, P. and Elliott, S.J. Active control of the flow-induced noise transmitted through a panel. AIAA Journal, 39(10), 2001, 1860-7. Analysis of the boundary layer noise transmitted through aircraft sidewalls. Proceedings of the 7th AIAA/CEAS Aeroacoustics Conference, Maastricht, The Netherlands, AIAA 2001-2111, 28-30 May 2001, 10pp. A wavenumber approach for the response of aircraft sidewalls to random pressure fluctuations. Proceedings of the 17th International Congress on Acoustics, Rome, Italy, Session 3D.02.05, 2-7 September 2001, 74. Papanagiotou, K. Speech enhancement for an in-ear communication system using body-conducted and acoustic signals. 141st Meeting of the Acoustical Society of America, Chicago, Illinois, June 2001, Poster. Papanagiotou, K., Rafaely, B. and *Shadle, C.H. Speech enhancement for an in-ear communication system using body-conducted and acoustic signals (Abstract). Journal of the Acoustical Society of America, 109(5.2), 2001, 2491. Rafaely, B. Active noise reducing headset – An overview. Proceedings of Inter-Noise 2001, The Hague, The Netherlands, 2, 27-30 August 2001, 589-98. Zones of quiet in a broadband diffuse sound field. Journal of the Acoustical Society of America, 110(1), 2001, 296-302. Spatially optimal Wiener filtering in reverberant sound fields. Proceedings of the IEEE Workshop on Applications of Signal Processing to Audio and Acoustics (WASPAA 2001), New York, USA, 21-24 October 2001, 159-62. Rafaely, B. and Hayes, J.L. On the modelling of the vent path in hearing aid systems. Journal of the Acoustical Society of America, 109(4), 2001, 1747-9. *Tseng, W.K., Rafaely, B. and Elliott, S.J. Performance and stability of single channel virtual microphone feedback controllers for an active headrest system. 2001 International Conference on Optimisation and Optimal Control, Tainan, Taiwan, 1-4 June 2001, unpaginated.

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Simpson, D.M., *Infantosi, A.F.C. and *Botero Rosas, D.A. Estimation and significance testing of cross-correlation between cerebral blood flow velocity and background electro-encephalograph activity in signals with missing samples. Medical & Biological Engineering & Computing, 39(4), 2001, 428-33. Simpson, D.M., *Panerai, R.B., *Evans, D.H. and *Naylor, A.R. A parametric approach to measuring cerebral blood flow autoregulation from spontaneous variations in blood pressure. Annals of Biomedical Engineering, 29, 2001, 18-25. Simpson, D.M., *Panerai, R.B., *Naylor, A.R. and *Evans, D.H. Impairment of cerebral autoregulation in the first hours after carotid endarterectomy (CEA). Abstracts of the 6th Meeting of the European Society of Neurosonology and Cerebral Haemodynamics, Lisbon, Portugal, 13-15 May 2001, 13. Parametric modeling of arterial blood pressure and blood flow velocity, for measuring cerebral autoregulation. Abstracts of IPEM Annual Scientific Meeting, Belfast, Northern Ireland, 12-15 September 2001, 175. Measurement of cerebral blood flow autoregulation from spontaneous changes in arterial blood pressure. Proceedings of the 6th Portuguese Conference on Biomedical Engineering, Faro, Portugal, 11-12 June 2001, 6pp. *Lazarev, V.V., Simpson, D.M., *Schubesky, B.M. and *de Azevedo, L.C. Photic driving in the electroencephalogram of children and adolescents: Harmonic structure and relation to the resting state. Brazilian Journal of Medical and Biological Research, 34, 2001, 1573-84. Individual frequency profile of photic driving in children and adolescents. Abstracts of the XV International Congress of Clinical Neurophysiology, Buenos Aires, 19 May 2001; Clinical Neurophysiology, 112(1), 2001, S38. *Miranda de Sá, A.M.F.L., *Infantosi, A.F.C. and Simpson, D.M. A statistical technique for measuring synchronism between cortical regions in the EEG during rhythmic stimulation. IEEE Transactions on Biomedical Engineering, 48(10), 2001, 1211-15. *Oliveira, C.G., Simpson, D.M. and *Nadal, J. Lumbar back muscle activity of helicopter pilots, and whole-body vibration. Journal of Biomechanics, 34(10), 2001, 1309-15. *Ramos, E.G., *Nadal, J., *Villar, M.N., *Lopes, J.M.A., Simpson, D.M., *Panerai, R.B. and *Evans, D.H., Comparação entre técnicas de avaliação de auto-regulação do fluxo sanguíneo cerebral de neonatos (Comparison between techniques to evaluate autoregulation of cerebral blood flow in neonates). Proceedings of the II Congreso Lationamericano de Ingenieria Biomédica, La Habana, Cuba, CD ROM, 23-25 May 2001, 5pp. Tam, P.S. and Rafaely, B. Efficient computation of very long optimal FIR filters. Fifth International Conference on Mathematics on Signal Processing, 2001, 7pp. Tan, M.H. and Hammond, J.K. Applications of principal components analysis for the detection and interpretation of non-linearities in measurement systems. Proceedings of the 4th International Conference on Acoustical and Vibratory Surveillance Methods and Diagnostic Techniques, Compiegne, France, 1, 16-18 October 2001, 197-209. White, P.R. The characterisation of bio-acoustic signals through time-frequency methods. Proceedings of the Institute of Acoustics 2nd Symposium on Underwater Bio-Sonar and Bioacoustic Systems, Loughborough, UK, 23(4), July 2001, 165-74. *Abrard, F., *Deville, Y. and White, P.R. A new source separation approach for instantaneous mixtures based on time-frequency analysis. Proceedings of the 5th Workshop on Electronics, Control, Modelling, Measurement and Signals, Toulouse, France, June 2001, 259-67.

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From blind source separation to blind source cancellation in the underdetermine case: A new approach based on time-frequency analysis. Proceedings of the 3rd International Conference on Independent Component Analysis and Signal Separation, San Diego, USA, 2001, 5pp. *Ewe, C., *Parker, K., White, P.R., *Henry, J.A. The pulse oximeter as a non-invasive measure of cardiovascular response to lower body negative pressure (Abstract). Scientific Meeting of the Faculty of Accident and Emergency Medicine, 2001, A8. *Lee, S.K. and White, P.R. The L-Wigner distribution and its use as a tool for condition monitoring. International Journal of COMADEM, 4(1), 2001, 5-11. *McWilliams, P.J., *McLaughlin, S., *Laurenson, D.I., Collis, W.B., *Weston, M. and White, P.R. Non-linear filtering for broadcast television: A real-time FPGA implementation. Proceedings of the International Conference on Image Processing, Thessaloniki, Greece, September 2001, 354-7. Zheng, Y., *Nixon, M.S. and Allen, R. Automatic lumbar vertebrae segmentation in fluoroscopic images via optimised, concurrent Hough Transform. Proceedings of the 23rd Annual Conference of the IEEE Engineering in Medicine and Biology Society, Istanbul, Turkey, Paper 3.4.2.7(227), 25-28 October 2001, 4pp. Automatic lumbar vertebrae registration using the Hough transform in digital videofluoroscopy. Proceedings of the European Congress of Medical Physics & Clinical Engineering (incl. IPEM Annual Scientific Meeting), Belfast, Northern Ireland, 12-15 September 2001, Physica Medica, XVII(3), 2001, 172-3. * - Not working in ISVR

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2. Teaching

Introductory Remarks Professor P A Nelson

Although it is becoming increasingly difficult to attract large numbers of students to our undergraduate courses, our policy of progressively increasing the entry requirements has had the highly beneficial effect of a notable improvement in the quality of students entering our courses. During the forthcoming year it is proposed to further develop our in-depth MEng course in Acoustical Engineering, since better quality engineering students are now more readily attracted to those MEng degrees that lead directly to professional engineering accreditation. It is also important to focus on methods for promoting our undergraduate courses in order to increase their visibility to potential applicants. During the forthcoming year attention will be given to developing our web site, in increasing contact with local schools and colleges, and developing promotional materials for distribution to sixth form physics students. The well publicised national difficulties with the teaching of mathematics at A-level will undoubtedly have an effect on our student recruitment, although at the time of writing the admissions statistics for the forthcoming year are suggesting that we may not suffer unduly. Turning to postgraduate teaching, the extremely difficult conditions being experienced in the automotive industry has resulted in a disappointing response to our Modular MSc in Automotive Refinement. Enquiries within the industry suggest that this is almost certainly simply the result of the prevailing economic conditions and that in the longer term training for engineers in this area will remain a priority. In the meantime, the decision has been taken to offer an automotive refinement ‘stream’ within the framework of the existing MSc in Sound and Vibration Studies. Timetabling adjustments will also enable a number of modules conducted within the framework of this course to be offered to external delegates. This year has seen the launch of the Masters Training Package in Biomedical Signal Processing, with the first module running in April of this year. It is a little early to anticipate the numbers of delegates that this course will succeed in attracting in the long term. The full-time MSc courses in Sound and Vibration Studies and in Audiology continue to run successfully and attract students of high quality. Thanks are due to all ISVR Course Chairmen, whose efforts on behalf of the Institute are greatly appreciated. It is appropriate to acknowledge the outstanding contributions made by Dr Neil Ferguson through his continued commitment to the organisation of our undergraduate courses.

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2.1 Undergraduate Courses Undergraduate Course Committee Chairman: Dr N S Ferguson

External factors are continually affecting the courses and now, as a result of the National Qualification Framework and the requirement of the production of the final version of the Programme Specifications, the correct terminology will see ‘courses’ replaced by ‘programmes’. The major change coming into place for the next academic session will be the compulsory Masters level content for the Part IV of the MEng programme. The possibility of running an in-depth MEng in Acoustical Engineering is the subject of current discussion. Fortunately, no changes were required for the academic year 2000-2001. A direct consequence of last year’s accreditation was the introduction of business studies lectures and the department would like to thank Drs M Jenkins (Acoustic Technology Limited) and N Baines (Consultant) for their contribution in May. Thanks are due to Land Rover for hosting an enjoyable industrial visit in November. The recent trend of fewer applicants and entrants, coupled with the increased interest in the combined honours programme, resulted in an almost equal number of students on the MEng/BEng and the BSc programmes. This is a cause for concern and is now the subject of the action on a number of fronts to increase awareness of the ISVR and its programmes via web-based material, direct contact with local schools/colleges and the provision of material on acoustics for teaching A-level Physics. There are also potential problems with low Mathematics AS level achievements, possibly reducing even further the pool of suitably qualified students for all engineering and science based programmes. In contrast, we do not appear to have any shortage in companies offering student placements or graduate employment, with a strong likelihood of at least one company offering a student bursary for the MEng/BEng programme. Detailed planning is well underway for running an undergraduate programme in Audiology; and with the likely demand in this area in the future our undergraduate numbers may take an upturn and increase. Once more thanks are due to both the academic teaching and support staff and also to the undergraduate external examiner, Professor Keith Attenborough. His thorough scrutiny of the draft examination papers, the moderation of our formal examination boards and especially interviewing the Part III project students have been greatly appreciated. Although fairly minor programme changes have taken place, it has been useful to have his views and more changes are envisaged with the imminent retirement of Dr Mike Fisher.

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2.2 MSc and Diploma Courses MSc Chairman and Examinations Officer: Professor C L Morfey

MSc Chairman’s report The two full-time Masters programmes, in Audiology and Sound and Vibration Studies, continue to train some 25-30 students between them per year, making a notable contribution to ISVR's output and at the same time providing a valuable source of researchers in ISVR at PhD level. In parallel, smaller numbers of part-time students have been registering on the modular Masters programmes in Automotive Refinement and Applied Digital Signal Processing; the teaching for these students consists of one-week modules that are also offered as one-off short courses for industrial participants. In recognition of the small numbers of part-time registered MSc students, the department is likely to offer the Automotive Refinement and Applied Digital Signal Processing programmes as specialist themes within the Sound and Vibration Studies package in future. Units in all three areas will continue to be offered as one-week modules, thereby widening the market for some of the more specialised topics. The intention is to create a flexible teaching pattern that can accommodate short one-week units and longer eight-week units within the same semester, giving maximum choice to students.

Audiology Course Organiser: Dr S Kapadia

All but one of the 18 students on the 2000/2001 session have successfully completed the MSc (subject to minor corrections of research project dissertations). The remaining student elected to receive the Diploma in Audiology. Seventeen new students (including two part-time) commenced the MSc Audiology programme in the 2001/2002 session. Four of these were from outside the UK (three EU and one non-EU). In addition, one visiting student successfully completed a training package designed for her during Semester 1 of the current session. (This student required a significant amount of training in Audiology for professional purposes, but not a full MSc or Diploma in Audiology.) Based on the success of this venture, the Department is likely to offer similar packages to other individuals in future, on a full cost-recovery basis. Virtually all the students due to complete during the current session already have suitable employment in place for October 2002. Demand for places for the 2002/03 session has been similar to previous years, and we expect again to have a full intake of approximately 20 students in October 2002. This is likely to include at least one new part-time student, who will complete the programme over two years. As required by the Faculty and University, the programme is now described in a standardised Programme Specification, with some modifications to assessment and progression rules to conform to a new Faculty-wide model. The Programme Specification also provides for a new exit point at Postgraduate Certificate level, in addition to the existing ones at Diploma and MSc level. The current session is the final one of the tenure of the present External Examiner, Dr Peter Bailey, of the University of York. The Department and staff involved in the Audiology programme acknowledge and thank him for his immensely valuable contribution to the Programme over the past three years.

Sound and Vibration Studies Course Organiser: Professor C L Morfey

This full-time MSc programme continues to attract a strong intake from around the world. Twelve students joined in October 2001, of whom ten remain (two UK mature entrants dropped out for financial and family reasons). Their countries of origin are France (3), Germany (2), Sweden, Portugal, Venezuela, and the UK (2). The reduction in load that was implemented in 2001/2002 (7 units instead of 8 in Semester 2) has been well received, and brings the Sound and Vibration Studies programme into line with other Faculty-taught Masters programmes.

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Dr Hugh Hunt joined as new External Examiner for the 2001/2002 session and has been involved as External Advisor in scrutinizing the new Programme Specification drawn up and approved over the past year. It comes into effect from October 2002.

Automotive Refinement Course Organiser: Dr T P Waters

The part-time MSc in Automotive Refinement has now completed its second academic year. All five core modules have now been developed, four of which have been run this past year. Three elective modules have also been developed and run. There were 66 delegates in total registered on the seven modules, 50% of which were external (mainly industrialists) and 50% were internal (PhD students, academic visitors, etc). There is only one student registered for the MSc programme, all other external delegates choosing to attend occasional modules as Masters level short courses. The programme is two years through the three-year EPSRC grant. Some revision of the programme may be required to ensure that it is self-financing beyond the end of the grant period.

Applied Digital Signal Processing Course Organiser: Dr B Rafaely

The modular MSc in Applied Digital Signal Processing offers engineers and professionals working in industry the opportunity to further develop their education in digital signal processing theory and practice. The course offers one-week modules that can be taken as short courses, or as part of a programme leading to a Postgraduate Certificate, Diploma or an MSc. The course offers five core modules, covering fundamental aspects of signal processing, while the various application areas are covered by a series of elective modules. Each one-week module is delivered through lectures and computer-based laboratories, a combination that is well appreciated by the students. Class size is typically 8-15 students, with the mixture of short-course delegates, MSc students and internal PhD students providing a stimulating environment. During the academic year, three modules were delivered and examined in each semester. The development of the course has been supported by the EPSRC under the Integrated Graduate Development Scheme (IGDS), while Texas Instruments also sponsor the course. The course details can be found at http://www.isvr.soton.ac.uk/Courses/MScADSP/.

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2.3 Continuing Education The modules developed for the modular MSc courses in Applied Digital Signal Processing and Automotive Refinement have continued to attract a considerable number of delegates who wish to take the modules as stand-alone courses. These delegates have the option of taking up to three stand-alone courses before deciding whether or not to register for the MSc. The ‘traditional’ courses (Advanced Course in Noise and Vibration, Engine Noise and Vibration Control, Vehicle Noise and Vibration) continue to attract international attendances. The Hearing and Balance Centre hosted its Balance Course again in December 2001. Balance 2001 took place over three days at Chilworth Manor Conference Centre and comprised an in-depth review of the assessment and management of people with balance disorders. The presenters included three experts from the USA, Professors Susan Herdman and Ronald Tusa from Emory University, Atlanta, and Professor Neil Shepard from the University of Pennsylvania. Other presenters were from the UK and included Ms Fiona Barker who is an Audiological Scientist from the King Edward VII Hospital in Windsor and Dr Peter West, Audiological Physician from Queen Alexandra Hospital, Portsmouth. Around sixty participants took part from a variety of professional disciplines and a variety of countries. In addition, several training days were organised by the South of England Cochlear Implant Programme aimed at professionals working with implanted children and also for the parents.

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2.4 ISVR Short Courses May 2001 to April 2002

Courses given at the ISVR Number Attending 2001

4-6 September Engine Noise and Vibration Control 11

6-9 September Vehicle Noise and Vibration 17

17-21 September Introduction to Signal Processing 1 9

20 September An Introduction to Cochlear Implants 30

24-28 September Advanced Course in Noise and Vibration 32

5-9 November Exhaust and Intake Silencer Design 2 13

26-30 November Fundamentals of Vibration 2 9

3-5 December Balance 2001 60

2002

23 January Cochlear Implant Troubleshooting Workshop 20

18-22 February Measurement Technology and Instrumentation 1 2 10

4-8 March Practical Introduction to Vehicle Noise and Vibration 2 10

18-22 March Vibration Control 2 18

8-12 April Active Control of Sound and Vibration 1 25

10 April Cochlear Implant Troubleshooting Workshop 14

18-19 April British Cochlear Implant Group Meeting 75

22-26 April High Frequency Structural Vibration 2 17

Courses given off premises A series of seven Noise Assessors’ Training Courses were provided for the MOD (Navy), attracting 89 students (in conjunction with the Health and Hygiene Division of the Institute of Naval Medicine, Gosport). 1 MSc Applied Digital Signal Processing Modules 2 MSc Automotive Refinement Modules

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2.5 International Collaboration Co-ordinator: Mrs M Z Strickland

SAVOIR The Eighth International Course on Noise and Vibration from Rail Transport Systems, organised jointly by the ISVR and TNO Delft, was hosted by Mr Friedrich Krueger of STUVA, Cologne, and held in Munich in April 2002. The course attracted 23 delegates from nine countries. It is hoped to repeat the course in 2004.

Université du Maine Dr Ferguson and Dr Brennan each spent two weeks at the Université du Maine to present lecture courses to engineers studying at the Ecole Nationale Supérieure d’Ingénieurs in April, May and June 2002.

Penn State University As part of the formal link with Penn State, Professor Elliott took part in the Annual Spring Workshop hosted by the Center for Acoustics and Vibration.

European Programmes The ISVR is co-ordinating the European Doctorate in Sound and Vibration Studies (EDSVS) which is funded by the European Community under the Marie Curie Multi-Partner Training Site Programme. This programme provides the opportunity to PhD students from EC Member and Associate States to visit one of the eight host EDSVS Institutions for a period between 3 and 12 months. The programme is now in its second year and a total of 29 students have either completed, begun or applied for the programme. Eleven students have chosen to work on a project offered by the ISVR.

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3. Consultancy

3.1 ISVR Automotive Design Advisory Unit Manager: Mr J D Dixon

Unit Development

Accommodation After nearly 30 years of split site working, the Unit has at last come under one roof. The final stage of this move took place in December 2001 when the Analytical and Computational team left the Highfield Campus to set up their computer system in newly acquired space at the Chilworth Laboratory. The move was far less traumatic than had been anticipated and their operation suffered minimal disruption. Although the day-to-day benefits of being on one site are clearly improving the efficiency of the Unit, there is the danger that the ADAU will become even more distanced from the main department: positive moves to prevent this occurring must be made.

Staffing This year has seen the retirement of the three most senior members of the ADAU, all of whom were instrumental in setting up the Unit in 1972. Jeff Baker, who retired at the end of May 2001, pioneered much of the early research into noise quality issues associated with crankshaft dynamics; his 2 bar/deg combustion rise rate criterion is still used by many throughout the industry. Yanis Erotokritos, who, over the past 25 years, developed the Unit’s powerful Finite Element and optimisation capability, retired at the end of February 2002. George Bazeley, who retired at the end of March 2002, designed, built and evaluated numerous prototype engines and components for customers throughout the world. The vast knowledge and expertise of these three engineers will be greatly missed. The Unit’s Finite Element team has been strengthened by the arrival of Kengo Koshimizu who has joined the Unit for 18 months on secondment from Komatsu in Japan.

Trading In line with just about all of the automotive industry, trading continues to be difficult. Customer numbers remain high, but the spend per customer has fallen, especially by the large multi national manufactures. Specialist equipment sales have been very buoyant, but sponsorship for large research projects has become increasingly hard to find.

Summary of Activities

Powertrains As in recent years the majority of the powertrain studies have focused more upon individual components rather than the total engine and transmission. Drive system noise of gears and chains continues to be studied. The dedicated chain noise rig has undergone considerable development throughout the year and is now able to apply a controlled load across the test span. Initial studies into the effect of lubrication and static tension have been carried out and plausible results have been recorded. Early attempts to model some of these observations have confirmed the belief that a number of different mechanisms of noise generation are present even with the simplest of chain systems. A fundamental study has been undertaken into the sound quality aspects of a twin camshaft, toothed belt drive system. The excitation mechanisms of a simple drive system with both steady drive and load are usually fairly easy to understand. However, when installed on an engine, with a fluctuating drive, a fluctuating load and a resonant supporting structure, the noise generation and subsequent sound quality issues are far from simple. An understanding of some of the associated sound quality issues has been achieved, but considerable effort is still required to develop a comprehensive model of belt noise generation.

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Turbochargers have been the subject for a number of studies, as both noise sources and attenuators. Although the unit has acquired considerable expertise with regard to noise generated at once-per-revolution and blade passage frequencies, this year, for the first time, both sub-synchronous and banded, speed-related noise mechanisms have been investigated, with satisfactory outcomes. For many years it has been recognised that both the turbine and the compressor of a turbocharger unit can provide significant attenuation to exhaust and intake noise respectively. In collaboration with members of the Fluid Dynamics and Acoustics Group a fundamental study has been carried out into the attenuation afforded by the compressor. A fairly accurate model has been developed for one particular installation, and now efforts must be put into improving the generic robustness of this model such that other configurations and installations may be considered. As diesel fuel injection systems continue to work at increasingly higher pressures, so the challenge to control their noise becomes ever harder. A recent study suggests that to avoid subjective issues due to injector impacts, serious consideration must now be given to the design of the injector clamping arrangement as well as the surrounding cylinder head geometry. The Banger Rig continues to earn its keep as a convenient means of model validation and base-lining of the structural attenuation performance of engine blocks. The now very large database on structures reveals some interesting historical trends with structural response having become spectrally smoother and generally convergent on a mass controlled asymptote. The hybrid modelling approach to engine noise proposed by ADAU some two years ago is at last being considered by the industry as a possible way forward. A combination of the power of finite element methods (for studying the structural detail) with the robustness of empirical and lumped-parameter methods for handling such elements as forcing functions, oil films, damping, etc, provides a quick, effective and easily implemented approach. The Unit’s ongoing intake and exhaust noise studies had an interesting variation this year with the need to considerably improve the spark arresting capabilities of an exhaust silencer. A totally new swirl-inducing geometry was conceived and developed such that the spark arresting performance of the final prototype far exceeded the design targets: the acoustic attenuation of the new silencer also measurably improved. Marine activities continue to increase; however, most projects involve gearbox or exhaust concerns rather than base engine noise.

Vehicles Tyre noise studies have continued throughout the year with the emphasis still on improving the methods by which it is measured. As the accuracy of measurement of the source noise and its transmission through the vehicle improve, so various anomalies are surfacing. Although test-to-test variability is now small, and the effect of weather conditions can be largely accommodated, there is evidence that a particular tyre can have a ‘bad day’ when its source noise (and corresponding interior noise) can change measurably for, as yet, unexplainable reasons. A new method for rapidly determining the source contributions to vehicle interior noise is showing great promise. When fully developed the technique should allow the balance between the primary sources to be determined within an hour with minimal instrumentation. Power unit component studies are increasingly being carried out in the operating vehicle. This year a number of cars have been driving around Hampshire laden with instrumentation. A major study into the potential refinement benefits of crankshaft bending dampers has been recently carried out using solely road testing. Although the instrumentation is necessarily more complex than in the test cell, the benefits of real vehicle conditions are considerable.

Instrumentation In the past year a further nine high frequency sound sources have been sold, six of which were to overseas customers. A Mark 2 low frequency sound source has been developed and delivered to the customer, who is most enthusiastic about its increase in power output. Both the high and low frequency sources continue to use

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in-neck pressure as an approximate monitor of volume velocity, but for a particular customer alternative methods are being investigated. A high quality, low cost, multi-channel acquisition system has been developed based upon a low budget recording studio interface for which software has been written to provide calibration and the functionality required for scientific and engineering applications. Although developed for a specific project, this new system is showing great potential as an additional mainstream data acquisition system.

Software Development As the vehicle noise modelling techniques developed in recent years by the Unit continue to spread throughout the industry, so the software support has become a growing activity. Suggestions for improvements and expansions to the packages are always being received, and if resources can be found customer-led development will continue.

Training Even in such hard times, the Engine and Vehicle short courses still appear to be popular, although last year the engine course attracted smaller numbers than in recent years. Fortunately, the situation looks as though it will be reversed this year with the engine course already close to capacity. The Unit was responsible for running the week long Exhaust and Intake MSc Module which proved to be very popular as a short course with 12 participants.

The Low Frequency Sound Source

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3.2 ISVR Consultancy Services Manager: Mr S J C Dyne

Manager’s Statement ISVR Consultancy Services is a self-funding advisory unit which carries out short- and medium-term consultancy and applied research projects for a wide range of clients in the public and private sectors. The unit operates on a commercial basis, with full-time engineering and support staff, and is a Founder Member of the Association of Noise Consultants (ANC). The Unit maintains close links with the ISVR Research Groups, and a number of projects are undertaken in collaboration with academic and research staff. The Unit website at www.isvr.co.uk includes details of the full range of services and facilities available. There have been a number of staff changes in the reporting period. Christos Karatsovis has joined the unit, expanding expertise in environmental noise and vibroacoustics and Mrs Diane Farrenden has become unit secretary. Brian Dennis has moved on to another acoustic consultancy and former Technical Manager, Bob Davis, has officially retired but continues to support unit activities in a new role as Associate Consultant.

Summary of Activities Consultancy projects are client-confidential. However, the following outline descriptions of projects in progress during 2001-2002 illustrate the range of work undertaken and the general direction of consultancy activities. During the period there were nearly 200 enquiries logged, with 28% becoming actual projects.

Environmental Noise A significant achievement has been the completion of our Black Country Forge and Foundry Project sponsored by the EU. Traditional metal working industries are important to the economy of the ‘Black Country’ area in the West Midlands. Many forges and foundries are located here, and many of these companies are small or medium sized businesses. However, forges and foundries are often situated close to residential areas. Much of their work is inherently noisy, and the noise is often impulsive and distinctive. The cost of noise control or of restricting working hours constrains development of these businesses and in some cases threatens their survival. Alleviation of community noise problems significantly improves the long-term prospects of foundries and forges with obvious benefits for employment and the local economy. The project was directed towards the study of noise emission from foundries and forges and the development of practicable, effective means of noise control within the budgets of small companies. The final report was published early in 2002 as a handbook directed towards forge and foundry owners and managers, although it may also be useful to Environmental Health Officers, to others involved in noise assessment and control, and to residents who are bothered by noise from a forge or foundry. Although some of the information relates specifically to forges and foundries, the same principles apply to most other industries, and the handbook has wide application. The handbook has also been published in full on our website at http://www.isvr.co.uk/bcffp. Demand for environmental noise assessment studies continues to grow in connection with new developments and in cases of alleged noise nuisance. In many cases, these projects lead to an appearance in Court or at Public Inquiry. Projects included the assessment of noise likely to result from various commercial and industrial developments such as mineral extraction and waste disposal sites including, in some cases, assessment of the impact of noise on wildlife as well as people. The public inquiry into the proposed container terminal on Southampton Water is still in progress and noise issues are expected to be heard in September of this year. The unit is working with academic staff in the Dynamics Group on an assessment of the level of groundborne noise likely to arise in the proposed Heathrow Terminal 5 from the underground railways feeding the terminal. A number of studies have concerned the assessment of the suitability for residential development of sites which are exposed to noise or vibration from transport or industry. Noise levels are generally assessed using standards set out in Planning Policy Guidance document PPG 24.

Litigation Work In addition to the public inquiry activity referred to above, a number of investigations have been carried out to prepare evidence in connection with criminal cases where questions were raised about ‘ear witness’ testimony or the ability of witnesses to hear or recognise specific sounds. In many other cases the unit has undertaken analysis

http://www.isvr.co.uk/

http://www.isvr.co.uk/bcffp

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of recordings made during alleged criminal activity, often with the aim of enhancing the audibility of recorded events or speech, and frequently involving transcription work. Further audio enhancement and transcription work has been carried out in civil cases under instructions from solicitors, increasingly as a ‘joint expert’ representing both sides in a case.

Noise and Vibration Control Engineering The unit has worked on a number of diverse projects involving the practical application of noise and vibration control techniques to industrial processes, machinery and consumer appliances. A project on the acoustic design aspects of a new high-speed, gas turbine-powered, luxury motor yacht is continuing. Other areas of activity include an investigation of excessive noise and vibration in the exhaust stack of a power station in Macau, China, calculations of low frequency noise from a diesel power station stack, groundborne noise from water pumping stations and estimates of shock noise from a fuel testing rig.

Structural Dynamics, Noise Control and Computational Acoustics Aeroacoustics projects this year have included the modelling of noise from wings and landing gears for Airbus UK to provide a comprehensive airframe noise model for the design of new aircraft. This work continues under the SILENCE(R) project with the Unit involved in several tasks on low noise design of landing gears and modelling of interaction effects between gears and flaps. Ongoing work on ray acoustics methods for Rolls- Royce plc has also continued with the codes now being used to design new liner configurations for testing under the SILENCE(R) project. The long term relationship with Vibro-Acoustic Sciences Inc in the marketing and use of the AutoSEA2 software has changed significantly this year and the Unit now provides mainly a customer training service in SEA methods and a capacity for consultancy projects. This is a useful change of role since it focuses on the technical strengths of the Unit. The expectation is that we should be able to significantly expand the value of AutoSEA2-related consultancy over the coming years, with a further boost anticipated when a mid-frequency combined SEA/FE package is released in the near future. As always in the acoustic consultancy field there has been a wide mix of other projects including noise control on water pumping stations, power stations and wind turbines, design and testing of absorptive materials and lightweight building materials and the design of a fire alarm. These projects provide a valuable and varied source of interest and income.

Test and Experimental Work The ISVR Consultancy Services operates and manages the main ISVR test chambers, including the large anechoic chamber, which is increasingly used for product testing as well as for undergraduate and postgraduate research. High intensity testing of aerospace components continues to be a major element of testing work. The valves in the chambers have been replaced recently to improve feedback control. This has slightly increased the maximum sound pressure level capability of the facility. The progressive wave tube facility, located in the P E Doak Aeroacoustics Laboratory has been used for major test programmes for composite aircraft fuselage components at SPLs of up to 165 dB. Laboratory tests to determine sound power levels have been performed on equipment such as shipboard machinery, computer peripherals, air-conditioning units, cellular telephone base stations and domestic ‘white goods’, using reverberant and hemi-anechoic test methods. The unit was tasked with an unusually demanding noise measurement project involving the measurement of the background noise levels inside the brand new acoustic test chambers at the National Physical Laboratory, for John Laing Construction. It was necessary to measure noise levels of –20 dB and less. A special purpose method was pilot tested in the ISVR anechoic room before the NPL room was completed. By making many repeat measurements and applying a statistical analysis we demonstrated that the noise levels in the new NPL room easily met the requirement, and our estimates of the actual noise levels in the room suggest levels are around –30 dB or lower in the middle and high frequency bands.

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Noise at Work, Communications, Hearing Conservation and Personal Injury Claims The year saw a continued rise in the assessment of noise exposures from headsets particularly for Call Centre agents. ISVR Consultancy Services assessed noise exposures in twelve call centres. Clients included two mobile phone network operators, a building society, a bank, a credit card company and UCAS, the University and Colleges Admission Service. One of the call centres was experiencing a number of ‘acoustic shock’ incidents, loud noise interference during calls, and had audio recordings of the incidents. The replaying of looped recordings into the call centre equipment, demonstrated that the agents’ turrets were limiting the gain for loud signals. Although the interference sounds were loud and unpleasant noise exposures, even at maximum volume settings would have been well below the action levels of the Noise at Work Regulations. In a related investigation, ISVR Consultancy Services investigated an incident in a Fire Brigade control room in which an operator had taken a 999 call from a payphone. The telephone was unfortunately positioned immediately below a fire alarm sounder, and the operator was exposed to the sound of the fire alarm through her headset for the duration of the call. By recreating the original occurrence we again found that the sound levels of the fire alarm from the headset were not excessive. Laboratory work on headsets has included the testing and evaluation of headphone limiters used by radio operators. This work was undertaken to provide information for a number of personal injury claims for hearing damage. ISVR Consultancy Services measured the performance of the limiters used with various types of headphone and compared the sound levels with the equipment’s specification and the action levels of the Noise at Work Regulations. We have also measured the output of radio earpieces to enable the manufacturer to attenuate their output to safe levels when used with specific types of personal radio. Further personal injury claim investigations have included:

• the measurement and assessment of the ultrasonic output of a dog deterrent which had been held close to a person’s ear

• an assessment of the likely noise levels and exposures of a former police firearms officer, and assessment of the effectiveness of hearing protection provided, from about 1980 onwards

• measurement of the sound levels from emergency vehicle sirens at close range to determine the sound level experienced by a garage worker who was working under a vehicle when a colleague sounded the siren sounded. The siren in this case was mounted in the engine compartment.

Enclosure used to measure microphone and pre-amplifier self-noise for a measurement project requiring measurements of levels as low as –20 dB

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Appendix 1 – Academic Awards and Student Prizes

Higher Degrees

Doctor of Philosophy Awarded during the Academic Year 2001-2002

P Brandstätt Low frequency noise in ventilation systems S Colam An investigation into an empirically designed passive sound absorber for use in recording studio control rooms L Gredmaier The effect of probe tone duration on psychoacoustic frequency selectivity M Kondracki Clinical applications of digitised fluoroscopy in the lumbar spine B Lineton Testing a model of stimulus frequency otoacoustic emissions in humans S Notley Prediction of epileptic seizures from depth EEG signals S Powell Development of continuous multi-modality monitoring in the intensive care

environment of a District General Hospital X Sheng Ground vibrations generated from trains T Takeuchi Systems for virtual acoustic imaging using the binaural principle

Master of Philosophy Awarded during the Academic Year 2001-2002

M Serrand Direct velocity feedback control of equipment vibration

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MSc and Diploma (Awarded in July 2002)

Master of Science – Audiology

Pass with Distinction S Blakemore Prevalence of dead regions in subjects with sloping sensorineural hearing loss

D Cane A comparison between the click and the chirp in threshold auditory brainstream response measurements

A Dyer Frequency specific auditory brainstem response using band-limited chirps

V Parfect Equivalence testing of the BKB and 1 hr sentence lists

D Rowan Influence of ear canal pressure on the cochlear place-frequency map

Pass R Buhagiar Ability of cochlear implant users to localise sounds

C Daldry One year follow up of analogue and digital hearing aid trial

J Davis A comparison of real-ear SPL measured directly and derived using the RECD and CDD

A Eid Variation in real ear sound pressure level due to earmould fit

E Fagan The measurement of acoustic spectra in normals

A Fry A study of spontaneous nystagmus and end-point nystagmus in normal subjects

S Gardner Cognitive functioning levels and the benefit from new technology hearing aids

T Killen Dead regions in the cochleae of teenagers who have a longstanding hearing-impairment

T N McGovern Simulated hearing loss and speech pattern audiometry

S Merritt Open-canal measurement of click-evoked otoacoustic emissions using maximum length sequences

J M Wilkinson A normative study of computerised dynamic posturography with head turn

Diploma J Austin

E Rourke

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Master of Science – Sound and Vibration Studies

Pass N Kubo Understanding the relationship between vehicle background noise and tyre

block pitch harmonics

C-S Lim Investigation of the vibration isolation of an automotive engine valve cover

E McGeehin Inversion for distributed mode loudspeakers

J Mendoza Lopez Semiclassical reverberation room modelling

J Mohammad Recording techniques for 5-channel virtual acoustic imaging

Master of Science – Applied Digital Signal Processing

Diploma A Newman

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First Degrees (Awarded in July 2002)

Master of Engineering

Acoustical Engineering

MEng with First Class Honours I Boorer D Howell

MEng with Second Class Honours (Upper division) C Cardoso C Heal

Bachelor of Engineering

Acoustical Engineering

BEng with First Class Honours I Back G Hodges J Laval P Pilla N Smethurst

BEng with Second Class Honours (Upper division) F Castres T Houghton D Nice

BEng with Second Class Honours (Lower division) M Allenby R Castro A Tomaz P Enée D Herries N Jones C Le Bourdat Z Linfoot I Macarthur

BEng with Third Class Honours G Aliberti P Davies P Papadopoulos

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Bachelor of Science

Acoustics and Music

BSc with Second Class Honours (Upper division) J Ford S Janes W Tudge L Whitehead

BSc with Second Class Honours (Lower division) A-M Jackman S Vassilouthis T Wilding

Acoustics with Music

BSc with Second Class Honours (Upper division) H Roberts-Powell G Smerin

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Student Prizes (Awarded in July 2002)

Undergraduate Students

Institute of Acoustic Prizes Part I Students N Bailey Part II Students L A Robertson Part III students I Back Final Year Project N Smethurst

ISVR Project Presentation Prize P Pilla R G White Prize G Hodges

MSc Students

Prizes for students of the 2001 intake The ISVR Audiology Prize C Felthouse The E J Richards Prize O Deille Journal of Sound and Vibration P E Doak Award J Kimber

Prize for students of the 2000 intake The Douglas Robinson Prize A Dyer

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Appendix 2 – Students

MSc and Diploma Students (October 2001 intake)

Audiology

MSc Nicola Bailey Michael Gilbert Sarah Bailey Michelle Hanson Karen Beckerleg Sally Harman Jane Bevan Emily Markesis Elaine Burke Tammy Norman Claire Cattermole Marniza Omar Sarah Fancy Graham Quin Catherine Felthouse Dawn Wall Constantina Georga

Sound and Vibration Studies

MSc Olivier Deille Tristram Love Benoit Gottrand Lisbeth Marty Steffen Hettler Rui Miguel Sá Ribeiro Martin Jerling Simon Shone James Kimber (Semester 1) Gabriel Vázquez Perez Michael Kraemer

Applied Digital Signal Processing

MSc Colin Almond John Small Graham Assinder Paul Tapsell Andrew Emerson John Thornton Graham Martin David White Jean-Marie Saisset Jonathon Wilcox Joanne Scruby

Automotive Refinement

MSc Fraser Innes

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Undergraduate Students (2001-2002 session)

Year One

Acoustical Engineering BEng Ross Handby Claire Kennedy Ioannis Matagos

MEng Stephen Brown Robert Shepherd Thomas Corbishley Jonathan Sims Daniel Lurcock Rhodri Williams Marios Psaras

Acoustics and Music BSc Katherine Day Toby Riches Alistair Manders Richard Thomas

Acoustics with Music BSc Nicholas Bailey Matthew Harrison Mark Broom Bethan Lewis Peter Bushell

Year Two

Acoustical Engineering BEng Christopher Brooks Adam Petty Spyridon Dromponis Alice Pickup Richard George Luke Robertson Andrew Long Peter Savage Neil Mackin Robert Singer Fotis Papatheodorou

MEng Neil Ashton Douglas Hammond Alex Campbell Jack Oclee-Brown

Acoustics and Music BSc Paul McGrath Jonathon Walters

Acoustics with Music BSc Robert Baker Robert Prowse Edward Harris Rebecca Young

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Year Three

Acoustical Engineering BEng Giuseppe Aliberti Nicholas Jones Martin Allenby Julien Laval Iain Back Colin Le Bourdat Fabrice Castres Zagan Linfoot Rodrigo Castro A Tomaz Ian Macarthur Peter Davies David Nice Pierre Enée Panagiotis Papadopoulos David Herries Pierpaolo Pilla Giles Hodges Nicholas Smethurst Tim Houghton

MEng Sonia Duarte

Acoustics and Music BSc Jonathon Ford Stelios Vassilouthis Ann-Marie Jackman Lindsay Whitehead Stuart Janes Thomas Wilding William Tudge

Acoustics with Music BSc Humphrey Roberts-Powell George Smerin

Year Four

Engineering Acoustics and Vibration MEng Ian Boorer Christopher Heal Clara Cardoso Daren Howell

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Appendix 3 – Extramural Appointments (at 30.04.02)

Professor R Allen Member of Technical Activities Committee on Control, IMechE Member of Advisory Group to Disability Equipment Assessment Centre, Department of Rehabilitation, Southampton General Hospital Member of the Scientific Committee, The INSPIRE Foundation (Integrated Spinal Rehabilitation Charity) Editor-in-Chief of Medical Engineering & Physics, Elsevier Science Ltd Member of Publications Committee, IPEM External Examiner, Kings College London, Medical Engineering and Physics (MSc) External Examiner, University of Surrey, Biomedical Engineering (MSc) Chair, UK Association of Institutions concerned with Medical Engineering (AIME) Member, UK Focus for Biomedical Engineering (Royal Academy of Engineering)

Dr D Anderton Chairman, British Standards Institution Committee EH/1/2 – Traffic Noise

Professor R J Astley Member, Board of Directors of the International Institute of Acoustics and Vibration (IIAV), 2000-2004

Dr M J Brennan Co-chair, Engineered Adaptive Structures III Conference

Mrs J C Brinton Member, Implant Centre Speech and Language Therapists Group Member, British Cochlear Implant Group External Examiner, University College London, BSc degree in Speech Sciences

Ms J Burgneay Examiner, British Association of Audiological Scientists, Certificate of Audiological Competence

Miss S G Cooper Member, American Speech-Language and Hearing Association

Mrs S E Cross Member, Management Committee DELTA (Deaf Education through Listening and Talking) Treasurer of SEAG (South Educational Audiologists’ Group)

Ms H E Cullington Editor, British Society of Audiology News

Mr R A Davis Member, British Standards Institution Committee: EH/1 – Acoustics

Mr J D Dixon Member, Editorial Board, Journal of Multi-body Dynamics

Professor P E Doak Editor-in-Chief, Journal of Sound and Vibration Adjunct Professor of Physics, Michigan Technological University

Mr S J C Dyne Member, Examining Board, Institute of Acoustics Member, Engineering Integrity Society, Software Validation Working Group Member, International Society of Air Safety Investigators

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Professor S J Elliott Member, IEEE Audio and Electroacoustic Technical Committee Associate Editor, Acustica with Acta Acustica Member, Editorial Board, Mechanical Systems and Signal Processing External Examiner, Department of Automatic Control and Systems Engineering, University of Sheffield

Ms J Eyles Member, Safety Working Group, British Cochlear Implant Group

Dr N S Ferguson Member, Dynamics Committee, Engineering Sciences Data Unit

Dr M J Fisher Member, Aircraft Noise Committee, Engineering Sciences Data Unit Member, Aeroacoustics Specialists Committee, Confederation of European Aerospace Societies

Dr I H Flindell Member, British Standards Institution Committee: EH/1/3/ – Industrial and residential noise Member, International Standards Organisation Working Group: ISO/TC43/SC1/WG45 – Description and measurement of environmental noise (revision of ISO 1996) Member, National Society for Clean Air: National Noise Committee

Mrs S J Flynn Member, Safety Working Group, British Cochlear Implant Group

Dr P Gardonio Member, Academic Board for the Doctorate in Sound and Vibration at the University of Ferrara, Italy

Professor M J Griffin Chairman, British Standards Institution Committee: GME/21/6 – Human exposure to mechanical vibration and shock Member, British Standards Institution Committees: GME/21 – Mechanical vibration and shock GME/21/6/1 – Hand-arm system vibration GME/21/6/2 – Human exposure to mechanical shock GME/21/6/3 – Whole body vibration GME/21/6/4 – Human exposure to vibration and shock in buildings and structures Member of Working Groups, International Organisation for Standardization, ISO/TC108/SC4: WG2 – Whole body vibration WG3 – Hand transmitted vibration WG5 – Biodynamic modelling WG7 – Safety aspects of tests and experiments WG8 – Vibrotactile perception WG11 – Vascular screening methods Member, European Committee for Standardization, Technical Committee CEN/TC231 – Vibration Member, International Advisory Committee of International Conference on Hand-arm Vibration Faculty of Occupational Medicine Working Group on hand-transmitted vibration, Royal College of Physicians

Professor J K Hammond Member, Editorial Board, Mechanical Systems and Signal Processing Associate Editor, Acustica with Acta Acustica

Dr K R Holland External Examiner, University of Salford, School of Acoustics and Electronic Engineering, MSc in Audio Acoustics

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Dr H V C Howarth Member, British Standards Institution Committee: GME/21/6/4 – Human Exposure to Vibration and Shock in Buildings and Structures

Mr B W Lawton Member, British Standards Institution Committees: EH/1/1 Loudness and Hearing Thresholds EPL/29 Electroacoustics

Professor T G Leighton Member of Council of Institute of Acoustics Member, Physical Acoustics Technical Committee of the Acoustical Society of America Member, Acoustical Oceanography Technical Committee of the Acoustical Society of America Member, Underwater Acoustics Committee of the Institute of Acoustics Member, Research Co-ordination Committee of the Institute of Acoustics Member, Advisory Editorial Board of Ultrasound in Medicine and Biology Member, Working Group 22 – Cavitation Detection and Monitoring, Accredited Standards Committee S1, Acoustical Society of America

Dr C H Lewis Member, British Standards Institution Committees: GME/21/6/3 – Whole-body vibration Member of Working Groups, International Organisation for Standardization, ISO/TC108/SC3: WG1 – Human response to Vibration Measuring Instrumentation

Professor M E Lutman Member, Royal National Institute for Deaf People (RNID) Medical Research Advisory Panel Member, Editorial Board, Noise and Health Specialist Advisor on Audiology, ENT News

Professor D J Mead Member, Editorial Board, Journal of Sound and Vibration

Professor C L Morfey Scientific Advisory Council of the Laboratoire d'Acoustique de l'Université du Maine (appointed by the French CNRS from June 1996 to present) Member, British Standards Institution Technical Committee PH/6/4 (pedal cyclist helmets)

Ms A E Morris Half-time temporary secondment to Department of Health: Project Manager, Modernising Audiology Education

Mr K J Munro Senior Examiner, British Association of Audiological Scientists, Certificate of Audiological Competence Member, Editorial Board, British Journal of Audiology

Professor P A Nelson Member, Board of International Commission for Acoustics Member of Rolls-Royce Power and Propulsion Systems Advisory Board Powerplant and Noise Panel

Miss E Payne Examiner, British Association of Audiological Scientists, Certificate of Audiological Competence

Professor M Petyt European Editor, Journal of Sound and Vibration

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Dr H I Philip Member of Working Group, International Organisation for Standardization, ISO/TC108/SC3: WG1 – Human Response to Vibration Measuring Instrumentation

Dr B Rafaely Visiting Scientist, Research Laboratory of Electronics, MIT, Boston

Dr B J Tester Visiting Professor, Imperial College of Science, Technology and Medicine

Dr D J Thompson Member, Editorial Board, Applied Acoustics

Mr C A Verschuur Examiner, British Association of Audiological Scientists, Certificate of Audiological Competence Head, British Association of Audiological Scientists Training Sub-Committee Member, British Association of Audiological Scientists Executive Committee

Dr J G Walker Member, Examining Board, Institute of Acoustics Deputy Chief Examiner, Institute of Acoustics Diploma Member, Examination Committee, Institute of Acoustics

Dr P R White Member, Editorial Board, Journal of Condition Monitoring and Diagnostic Engineering Management External Examiner, Salford University

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Appendix 4 – Lectures and Seminars (2001-2002 session)

Date Title Presenter

Seventh E J Richards Lecture 26 November 2001 Neural mechanisms of hearing Professor A R Palmer

Head of Neurophysiology, MRC Institute of Hearing Research

Seminars 11 October 2001 Introduction to the ISVR Professor P A Nelson

Director, ISVR

18 October 2001 Health and Safety Presentation Mr J F Hawkes University Safety Advisor

25 October 2001 Spatial audio Dr F Rumsey University of Surrey

1 November 2001 Acoustical engineering at Renault Madame V Maillard Renault, Paris

8 November 2001 Frank Fahy’s Sonic Circus Professor F J Fahy ISVR

15 November 2001 Aircraft noise Mr N Birch Rolls-Royce plc, Derby

22 November 2001 The rough and the smooth of booms and bangs Professor K Attenborough University of Hull

29 November 2001 The classical guitar: Tone by design Dr B Richardson Cardiff University

6 December 2001 Stressful dynamics Dr N Lieven Bristol University

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Appendix 5 – Research Publication Statistics (for the calendar year 2001)

In conformity with current practice of the University, the data below refer to material the publication dates of which fell within the calendar year 1 January to 31 December 2001, with the exception of a few delayed titles that could not be included in the last Annual Report. Key:

DG – Dynamics Group FDAG – Fluid Dynamics and Acoustics Group HSG – Human Sciences Group SPCG – Signal Processing and Control Group CU – Consultancy Units (ADAU, ICS)

Category Number of publications

DG FDAG HSG SPCG CU* All Groups

Books - 1 - - - 1 Chapters in Books 2 1 3 1 - 7 Papers in scientific and technical journals

(including Technical Notes) 24 28 24 28 - 104

Papers in conference proceedings (refereed) 1 11 - 12 - 24 Papers in conference proceedings 20 18 30 23 - 91 ISVR Technical Reports - 3 - - - 3 ISVR Memoranda 15 - - 4 - 19 ISVR Contract Reports † 14 7 2 7 - 30 Miscellaneous # - - 4 - - 4

Totals by Group 76 69 63 75 - 283 Grand total

* Consultancy reports are not included

† For reasons of client confidentiality, titles of Contract Reports are no longer included in the publication lists at the end of Chapters 1.1-1.4.

# Comprises Book Reviews, Journal Abstracts, Patents etc.

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Appendix 6 – External Examiners for the Undergraduate and MSc Courses

(2001-2002 session)

Undergraduate Courses Professor K Attenborough, School of Engineering, University of Hull

MSc Courses

Audiology Dr P J Bailey, Department of Psychology, University of York

Sound and Vibration Studies Dr H Hunt, Department of Engineering, University of Cambridge

Automotive Refinement Professor R Sharp, Department of Automotive Combustion and Energy Engineering, Cranfield University

Applied Digital Signal Processing Dr R W Stewart, Department of Electronic and Electrical Engineering, University of Strathclyde

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Appendix 7 – List of Formal International Links

Formal Memoranda of Understanding exist between the ISVR and the following establishments for the purpose of promoting collaboration on research and development programmes of mutual interest by means of staff and student exchanges.

College of Engineering Anna University ............................................................................................................ Chennai, India

RMK Engineering College ........................................................................................... Chennai, India

Acoustics and Vibration Laboratory Universidade Féderal da Santa Catarina .................................................................... Florianópolis, Brazil

Center for Noise and Vibration Control Korea Advanced Institute of Science and Technology ................................................. Taejeon, Korea

College of Engineering Pennsylvania State University ...................................................................................... University Park PA, USA

Biomedical Engineering Group, Electronics Department University of Naples ..................................................................................................... Naples, Italy

Institut National des Sciences Appliquées .................................................................... Lyon, France

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Appendix 8

Principal Intramural Responsibilities of Staff and Student Representatives

(at 30.04.02)

Officers of Departmental Committees Computing Facilities Committee S J C Dyne (Chairman)

Departmental Board P A Nelson (Chairman) M Z Strickland (Secretary)

Equipment Grant Committee M E Lutman (Chairman)

Human Experimentation Safety & Ethics Committee M J Griffin (Chairman) E L Gullidge (Secretary)

MSc Course Committee C L Morfey (Chairman)

Scientific Advisory Committee P A Nelson (Chairman) M J Fisher (Secretary)

Undergraduate Course Committee N S Ferguson

Services and Safety P A Nelson (Chairman)

Departmental Responsibilities Academic Secretary M Z Strickland

Admissions and recruitment: BEng/MEng Acoustical Engineering M J Brennan BSc Acoustics and/with Music M J Brennan Foundation Year M J Brennan MSc Audiology S Kapadia MSc Automotive Refinement T P Waters MSc Sound and Vibration Studies C L Morfey MSc Applied Digital Signal Processing B Rafaely

Annual Report F J Fahy (Editor) S J Brindle

Computing Liaison Officer J A Haughton

Course Organisers Undergraduate courses: BEng/MEng Acoustical Engineering N S Ferguson BSc Acoustics and/with Music N S Ferguson Foundation year N S Ferguson

MSc and diploma courses: Audiology S Kapadia Automotive Refinement T P Waters Sound and Vibration Studies C L Morfey Applied Digital Signal Processing B Rafaely

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Departmental Responsibilities (cont) Departmental Secretary M Z Strickland

Departmental Autumn Term Seminar Series M Z Strickland

European liaison M Z Strickland

European Research Co-ordinator P Gardonio

Examination Officers Undergraduate N S Ferguson MSc C L Morfey

Industrial liaison C J C Jones

Library Representative S Kapadia

Postgraduate admissions and visitors P A Nelson M Z Strickland

Postgraduate research monitoring P A Nelson

Public lectures M J Fisher P A Nelson

Public relations P A Nelson M Z Strickland

Quality Assessment of Education P A Nelson N S Ferguson M E Lutman

Safety Officer J Taylor

Staff appraisal system and Investors in People P A Nelson M Z Strickland

Student representatives (on Departmental Board and course committees) 1st year C Kennedy 2nd year R Singer 3rd year L Whitehead 4th year C Heal MSc Audiology D Wall MSc Automotive Refinement F Innes MSc Sound and Vibration Studies T Armstrong / G Vázquez Perez MSc Applied Digital Signal Processing D White Research students T Armstrong / N Hatcher / A Morris / J Rose

University Research Report P A Nelson S J Brindle

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Membership of Faculty Committees Academic Standards and Quality Committee N S Ferguson

Graduate School Board D J Thompson

Staff Development M Z Strickland M J Brennan

Advisory Units P A Nelson

Board of the Faculty of Engineering and Applied Science All ISVR academic staff

CEDC Steering Committee P A Nelson

Computing and CAD S J C Dyne P R White

Equal Opportunities M Z Strickland

Finance and Policy P A Nelson

MEng Course Committee N S Ferguson

Research S J Elliott

Staff Review Committees Academic Staff S J Elliott Academic Related and Advisory Units’ Staff S J Elliott Clerical and Technical Staff P F Joseph

Undergraduate Admissions M J Brennan

Membership of University Committees Assessment of Departmental Performance M J Griffin

General Staff Committee J K Hammond

Board of the Faculty of Medicine, Health and Biological Sciences R Allen

Senate S J Elliott M J Griffin P A Nelson

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Appendix 9 – Acknowledgements of Research Sponsors

The Institute of Sound and Vibration Research gratefully acknowledges support for research received from the following Organisations: American Bureau of Shipping Cochlear (UK) Defeating Deafness Danfoss A/S Comfort Division, Denmark Department of Trade & Industry (DTI) Engineering and Physical Sciences Research Council (EPSRC) ESDU International Plc European Commission: VIBSEAT European Commission: COMPASS European Commission: Framework 5 Ford Motor Company (UK, Europe, USA) Harley-Davidson Motor Company Operations Health & Safety Executive HEFCE Hoare Lee Acoustics Institute of Naval Medicine, Alverstoke Jaguar Cars Ltd Knowles Electronics Company (USA)

Korean Research Institute of Standards & Science Med-el (UK) Medical Research Council (MRC) Ministry of Defence (MOD) Pandrol Rail Fastenings Ltd Phonak Hearing Instruments QinetiQ Ltd Renault, France Rolls-Royce plc Royal National Institute for Deaf People (RNID) Samsung Electronics Co Ltd SNCF, France Snell & Wilcox Ltd Transport Research Laboratories (TRL) The Foundry The Royal Society Wessex Cardiac Trust Wessex Heartbeat

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Appendix 10 – Honours, Awards, Medals (at 30.04.02)

Professor T G Leighton

Tyndall Medal of the Institute of Acoustics 2001.

Professor P A Nelson

Rayleigh Medal of the Institute of Acoustics 2002.

Professor M Petyt Elected Fellow of the International Institute of Acoustics and Vibration. Awarded the Golden Jubilee Directors' Award, Central Building Research Institute, Roorkee, India, for the year 1999-2000 for the paper, Chakraverty, S. and Petyt, M. ‘Vibration of non-homogeneous plates using two-dimensional orthogonal polynomials and shape functions in the really rich method’, Proceedings of the Institute of Mechanical Engineers, 213(C), 1999, 704-714.

Mr G Stimpson

October 2001, Ford Motor Company Technical Achievement Award for the Development of a Calibrated Point Noise Source.

Dr M C M Wright EPSRC Advanced Research Fellowship.

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