Lecture Notes in Artificial Intelligence

Subseries of Lecture Notes in Computer Science

Edited by J. G. Carbonell and J. Siekmann

Lecture Notes in Computer Science Edited by G. Goos, J. Hartmanis and J. van Leeuwen

990

Carlos Pinto-Ferreira

Nuno J. Mamede (Eds.)

Progress in Artificial Intelligence

7th Portuguese Conference on Artificial Intelligence, EPIA '95 Funchal, Madeira Island, Portugal October 3-6, 1995 Proceedings

Springer

Series Editors

Jaime G. Carbonell, Carnegie Mellon University, USA

J6rg Siekmann, University of Saarland, DFKI, Germany

Volume Editors

Carlos Pinto-Ferreira ISR/IST, Torre Norte Av. Rovisco Pais, P-1000 Lisboa, Portugal

Nuno J. Mamede INESC/IST Av. Alves Redol, 9, P-1000 Lisboa, Portugal

Cataloging-in-Publication Data applied for

Die D e u t s c h e B i b l i o t h e k - C I P - E i n h e i t s a u f n a h m e

P r o g r e s s in a r t i f i c ia l i n t e l l igence : p r o c e e d i n g s / 7 th Por tuguese C o n f e r e n c e on Ar t i f i c i a l I n t e l l i gence , E P I A '95, Funcha l , M a d e i r a I s l and , Por tuga l , O c t o b e r 3 - 6, 1995. Car los P i n t o - F e r r e i r a ; N u n o J. M a m e d e (ed.). - Ber l in ; H e i d e l b e r g ; N e w Y o r k ; B a r c e l o n a ; Budapes t ; H o n g K o n g ; L o n d o n ; M i l a n ; Par is ; T o k y o : Spr inger , 1995

(Lecture notes in computer science ; Vol. 990 : Lecture notes in artificial intelligence) ISBN 3-540-60428-6

NE: Pinto-Ferreira, Carlos [Hrsg.]; EPIA <7, 1995, Funchal>; GT

CR Subject Classification (1991): 1.2

ISBN 3-540-60428-6 Springer-Verlag Berlin Heidelberg New York

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Preface

EPIA'95 is the seventh conference organized under the auspices of the Portuguese Association for Artificial Intelligence (APPIA). Since its first conference, in 1985, the EPIA has grown steadily in quality, particularly since its first international conference (1989), when English was adopted as the official language, allowing the exchange of information between Portuguese and foreign researchers.

When we proposed the organization of the EPIA'95 conference, we committed ourselves to the following strategic objectives: the achievement of high standards of quality, the broadening of its audience, and, last but not least, the motivation of young researchers for the most exciting area of research humankind has ever approached: Artificial Intelligence. As a mat ter of fact, what unites researchers working in such different fields as non-monotonic logics, vision, planning, con- nectionism, and the lambda calculus, to name but a few, is the sharing of the very same objective: the dream of building an intelligent agent.

In regard to standards of quality, few words need to be said when outstanding invited lecturers such as Marvin Minsky, Manuela Veloso, Luls B. Almeida, and Rodney Brooks participate in the event, or when very distinguished members of the AI community accepted to participate in the EPIA'95 Program Committee - - to make it the first with a strong international component. We dared to invite these researchers to be present at our conference, and we are honored and glad for their acceptance: To all of them we address our thanks.

The EPIA'95 paper revision process was very tough: We received 167 sub- missions (from Russia to Canada, from the USA to China, from Portugal to Singapore). From that initial set, we rejected 17 for being received after the deadline, and out of the remaining 150, 30 papers were selected as full papers and 15 for poster presentation. Twenty-one Program Committee members and almost 200 reviewers worked very hard to ensure a very strict paper revision pro- cess (triple, blind, AAAI-94 style). However, it is impossible to manage such a process, taking place in a very limited amount of time, without making mistakes and being unfair (at least, unconsciously). The responsibility for these mistakes rests completely with the Program Co-chairs. We would like to take this oppor- tuni ty to thank the authors and reviewers for their co-operation and patience! The remarkable quality of the papers collected here result from their work and enthusiasm.

At the time we started organizing EPIA'95, we decided that this year's con- ference should serve as a forum for a debate on the foundations of Artificial Intelligence. Although being logicists and theoreticians, we share the point of view that there are neither "good" nor "bad" approaches to Artificial Intelli- gence: The problem the AI community has is certainly too difficult to have a single, canonical, and orthodox answer. Therefore, we have committed ourselves to motivating researchers from the various sub-fields of AI, hence broadening the scope of the conference.

VI

Our third concern was about the responsibility of t ransmit t ing our enthusi- asm to young students and researchers in AI. This was the reason we contacted sponsors in order to finance about 150 scholarships to help graduate, master 's , and Ph.D. students to participate in the conference. Without the support of BNU (Banco Nacional Ultramarino) and ACM Sigart, this critical aspect would not have been possible.

Some comments should also be made about the venue we have chosen for this year 's conference. The Madeira Island offers ideal conditions for conferences: the warmth of their people, the mildness of the climate, and very good logistic conditions. We would like to take this opportunity to thank the Governo Regional da Madeira, particularly the Secretaria Regional de Educa~o , the Secretaria Regional de Turismo e Cultura, and CITMA for their support and enthusiasm from the very beginning of this process.

Finally, we would like to thank all the EPIA'95 supporters, namely,

BNU - Banco Nacional Ultramarino Governo Regional da Madeira CITMA - Centro de C~zT da Madeira IST - Insti tuto Superior T~cnico INESC - Insti tuto de Engenharia de Sistemas e Computadores C O M P U L O G - N E T FLAD - F u n d a ~ o Luso-Americana para o Desenvolvimento J N I C T - Jun ta Nacional de Investigaw Cientffica e Tecnol6gica F u n d a ~ o para a D ivu lga~o das Tecnologias de Informaq~o F u n d a ~ o Calouste Gulbenkian ACM - Sigart SISCOG - Sistemas Cognitivos IBM Portuguesa EDP - Electricidade de Portugal, S.A. TAPair Portugal

Without their support, neither the conference nor these proceedings would have been possible.

Lisbon, June 1995

Carlos Pinto-Ferreira

Nuno Jodo Mamede

Programme & Conference Co-Chairs

Carlos Pinto-Ferreira

Technical Univ. of Lisbon - IST ISR, Av. Rovisco Pais 1000 Lisbon, Portugal Voice: +351 (1) 8418270 Fax: +351 (1) 8418291 E-mail: cpf@isr.isr.ist.utl.pt

Nuno Jo~o Mamede

Technical Univ. of Lisbon - IST INESC, Apartado 13069

1000 Lisboa, Portugal Voice: +351 (1) 3100234

Fax: +351 (1) 525843 E-marl: Nuno.Mamede@inesc.pt

Program Commit t ee

Ant6nio Porto (Universidade Nova de Lisboa, Portugal) Benjamin Kuipers (University of Texas at Austin, USA) Bernhard Nebel (University Ulm / DFKI Saarbruecken, Germany) Carlos Pinto-Ferreira (Technical Univ. of Lisbon - IST / ISR, Portugal) David Makinson (UNESCO, France) Erik Sandewall (Linkdping University, Sweden) Ernesto Costa (Universidade de Coimbra, Portugal) Helder Coelho (Technical University of Lisbon - ISEG / INESC, Portugal) Jogo Pavgo Martins (Technical University of Lisbon - IST, Portugal) John Self (Lancaster University, UK) Jos~ Carmo (Tech. Univ. of Lisbon - IST / Univ. da Madeira, Portugal) Lauri Carlson (University of Helsinki, Finland) Luc Steels (VUB A1 Lab, Belgium) Luigia Carlucei Aiello (Universild di Roma La Sapienza, Italy) Luis B. Almeida (Technical University of Lisbon - IST / INESC, Portugal) Luis Moniz Pereira (Centro de Informdtica e Int. Art., DI/UNL, Portugal) Luls Monteiro (Universidade Nova de Lisbon, Portugal) Manuela Veloso (Carnegie Mellon University, USA) Maria Cravo (Technical University of Lisbon - IST, Portugal) Miguel Filgueiras (University of Porto, Portugal) Nuno Mamede (Technical University of Lisbon - IST / INESC, Portugal) Yoav Shoham (Stanford University, USA) Yves Kodratoff (CNRS, France)

A. Brunie-Taton Aaron Sloman Abhaya Nayak Alvaro del Val Ana Fred Ana P. Toms Antdnia Lopes Antdnio Leitio Arlindo M. Oliveira Aur61ien Slodzian Bernadete Ribeiro Carlos Bento Carsten Kindermann Daniel Borrajo David Makinson Elissa Feit Ernesto Costa Fernando A. Silva Franeesco M. Donini Francisco M. Dionfsio Geoff Gordon Gilles Bisson Graqa Gaspar H. Mignot Harald Ruess H61der Araujo Henry Soldano Hudson Turner Isabel Ribeiro Jim Blythe Jos Lemos Jogo P. Martins Joaquim N. Aparfcio John Zelle Jos6 J. Alferes Jos6 L. Fiadeiro Jfirgen Dix Kimmo Koskenniemi Laurent Miclet Lufs B. Almeida Lufs Correia Lufs Monteiro Marco Cadoli Maria R. Cravo Maurice Pagnucco Miehele Sebag Nicolas Graner Nuno Mamede Paulo C. Reis Pedro Aguiar Pedro Lima Peter Stuer Raman Rajagopalan Rich Caruana Ronald Schrooten Sabine Broda Salvador P. Abreu Syed S Aft Timo ltonkela Vitor S. Costa Yury Smirnov

Reviewers A. Cornuejols Artur M. Dias Alberto Tom6 Amflcar Cardoso Ana M. Moreira Andrea Hemprich Ant6nio Braneo Ant6nio M. Florido Armando Matos Austin Tate Bernard Manderick Carlos V. Dams Christer Bs Daniele Nardi Deepak Kumar Eriea Melis Eva Ejerhed Fernando M. Silva Francisco A. Veiga Gabriel David Gerd Brewka Giovanni Rumolo Greg Restall Hans Chalupsky Harri Arnola Helder Coelho Herbert Jaeger Ilkka Niemels Jana Koehler Jo~o BMsa Joio P. Costeira Joaquim Baptista Joel Quinqueton Jos6 Santos-Victor Jos6 P. Lea] Jos6 V. Ofiveira Karen Ehrlich Kris Van Marcke Luis M. Custddio Lu/s Caires Luis Moniz Luc Goossens Marco Schaerf Mark Ryan Micheal Hewett Miguel Filgueiras Norman McCain Paolo Liberatore Paulo J. Oliveira Pedro A. Matos Pedro Resende Philip Goetz Renwei Li Richard Wyatt Ronen Brafman Sabine Geldof Stefan Wrobel Thibault Langlois Ulf Hermjakob William J. Rapaport Yvonne Waern

Aarno Lehtola Abdelhamid Mellouk Alistair E. Campbell Ana Cardoso Ana Paiva Andrea Schaerf Anthony Cohn Ant6nio Porto Astro Teller Bart De Boer Bernhard Hollunder Carlos Pinto-Ferreira Claire Nedellec David Hogg Dietmar Dengler Erik Sandewall Fabio Massacci Fernando M. Pires Francisco Menezes Gabriel P. Lopes Gerd Wagner Gordon Novak Grigorios Antoniou Hans-Jiirgen Biirckert Hans- Jiirgen Profitlich Helena Sofia Pinto Herbert Kay Irene P. Rodrigues Jeff Rickel JoS, o Cachopo JoS~o P. Neto Joaquim Filipe John Self Jos6 Carmo Jos6 L. Ferreira Juergen Paulokat Karen Haigh Lars Ahrenberg Luis Antunes Lufs Camarinha-Matos Luis Moniz Pereira Luigia Carlucci Aiello Margarida Mamede Mary-Anne Williams Michel Wermelinger Nelma Moreira Nuno Guimars Paulo B. Menezes Pavlos Peppas Pedro Barahona Peter Clark Pierre Brezellec Riccardo Poli Rita Ribeiro S. Augier Siddarth Subramanian Stuart C. Shapiro Thierry Van de Merckt Vasco Vasconcelos Witold Lukaszewicz Zaron Wirth

T a b l e o f C o n t e n t s

A u t o m a t e d R e a s o n i n g a n d T h e o r e m P r o v i n g

Terminologica l M e t a - R e a s o n i n g by Reif icat ion and Mul t ip le C o n t e x t s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Klemens Schnattinger, Udo Hahn and Manfred Klenner CLIF, Freiburg University, Germany

A New Con t inuous P ropos i t i ona l Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Riccardo Poli, Mark Ryan and Aaron Sloman SCS, The University of Birmingham, UK

S u p e r - P o l y n o m i a l Speed-Ups in P r o o f Length by New Tauto logies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Uwe Egly FG Intellektik, TH Darmstadt, Germany

B e l i e f R e v i s i o n

Bel ie f Rev is ion in N o n - M o n o t o n i c Reasoning . . . . . . . . . . . . . . . . . . . . . . . . 41 Josd Alferes, Luls Moniz Pereira and T. Przymusinski DM, U. l~vora, and CRIA, U. Nova de Lisboa, Portugal, and University of California at Riverside, USA

A N e w R e p r e s e n t a t i o n o f J T M S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Truong Quoc Dung IRIDIA, Universitd Libre de Bruxelles, Belgium

C o n s t r a i n t - B a s e d R e a s o n i n g

The Re t r i eva l P r o b l e m in a Concep t Language wi th N u m b e r Res t r i c t i ons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Aida Vit6ria, Margarida Mamede and Luis Monteiro DI, Universidade Nova de Lisboa, Portugal

Formal iz ing Local P r o p a g a t i o n in Cons t ra in t Ma in tenance Sy s t ems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Gilles Trombettoni INRIA-CERMICS, France

A Dependency Parser of Korean Based on Connect ionis t / Symbolic Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Jong-Hyeok Lee and Geunbae Lee Pohang University of Science and Technology, Korea

A Symbiot ic Approach to Arc and P a t h Consis tency Checking .. . 107 Pierre Berlandier INRIA-CERMICS, France

D i s t r i b u t e d A r t i f i c i a l I n t e l l i g e n c e

W h e r e Do In ten t ions Come From?: A Framework for Goals and In tent ions Adopt ion , Derivat ion and Evolut ion . . . . . . . . . . . . . . . 115 Gra~a Gaspar and Helder Coelho Faculdade de Ci@ncias de Lisboa, and INESC, Portugal

A Closer Look to Artif icial Learning Env i ronments . . . . . . . . . . . . . . . . 129 Helder Coelho, Augusto Eus@bio and Ernesto Costa INESC, Portugal, and DEI, Universidade de Coimbra, Portugal

Bui ld ing Mul t i -Agen t Societies f rom Descript ions to Systems: In te r -Layer Transla t ions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 Helder Coelho, Luis Antunes and Luis Moniz INESC, Portugal

G e n e t i c A l g o r i t h m s

GA/TS: A Hybr id Approach for Job Shop Scheduling in a P r o d u c t i o n Sys tem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 Jos6 RamSn Zubizarreta Aizpuru and Javier Arrieta Usuns Facultad de Informs de San Sebastian, Spain

M a c h i n e L e a r n i n g

A Contro l led Exper iment : Evolut ion for Learn ing Difficult Image Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 Astro Teller and Manuela Veloso Carnegie Mellon University, USA

Min imal Model Complex i ty Search . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Chris McConnell CMU School of Computer Science, USA

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Cha rac t e r i za t i on of Classification Algor i thms . . . . . . . . . . . . . . . . . . . . . . 189 Jo~o Gama and Pavel Brazdil LIACC, Universidade do Porto, Portugal

N e u r a l N e t w o r k s

Neurons , Glia and the Border l ine Between Subsymbol ic and Symbol ic Process ing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 J. G. Wallace, K. Bluff Swinburne University of Technology, Australia

N o n - M o n o t o n i c R e a s o n i n g

A r g u m e n t s and Defeat in Argumen t -Based Nonmono ton ic Reason ing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 Bart Verheij University of Limburg, The Netherlands

A Prefe rence Semant ics for G r o u n d Nonmonoton ic Moda l Logics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Daniele Nardi and Riccardo Rosati DIS, Universit~ di Roma "La Sapienza", Italy

Logical Omniscience vs. Logical Ignorance On a D i l emma of Epis temic Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237 Ho Ngoc Duc ILPS, University of Leipzig, Germany

P l a n n i n g a n d C a s e - B a s e d R e a s o n i n g

On the Role of Spl i t t ing and Merging Past Cases for Genera t ion of a New Solut ion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Carlos Bento, Penousal Machado and Ernesto Costa DEI, Universidade de Coimbra, Portugal

T h e o r e m Prov ing by Analogy - A Compel l ing Example . . . . . . . . . . 261 Erica Melis Department of AI, University of Edimburgh, Scotland

Non-Atomic Act ions in the S i tua t ion Calculus . . . . . . . . . . . . . . . . . . . . . 273 Josd Jdlio Alferes, Renwei Li and Lufs Moniz Pereira CRIA and DCS, Universidade Nova de Lisboa, Portugal

xll

P lann ing U n d e r Uncer ta in ty : A Qual i ta t ive Approach Nikos I. Karacapilidis FIT.KI, GMD, Sankt Augustin, Germany

. . . . . . . . . . . . 285

Q u a l i t a t i v e R e a s o n i n g

Qual i ta t ive Reason ing U n d e r Unce r t a in ty . . . . . . . . . . . . . . . . . . . . . . . . . . 297 Daniel Pacholczyk DMI, U.F.R., Sciences d'Angers, France

Sys temat i c Cons t ruc t i on of Qual i ta t ive Phys ic s -Based Rules for Process Diagnost ics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311 Jaques Reifman and Thomas Y.C. Wei Argonne National Laboratory, USA

R o b o t i c s a n d C o n t r o l

I n t e g r a t e d Process Supervision: A S t r u c t u r e d Approach to Exper t Contro l . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 Chai Quek, P.W. Ng, M. Pasquier Nanyang Technological University, Singapore

Using Stochas t ic G r a m m a r s to Learn R o b o t i c Tasks . . . . . . . . . . . . . . 335 Pedro U. Lima and George N. Saridis ISR, Technical Univ. of Lisbon, Portugal, and Rensselaer Polytechnic Institute, USA

T h e o r y o f C o m p u t a t i o n

Cons t ra in t Categor ia l G r a m m a r s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347 Luls Damas and Nelma Moreira LIACC, Universidade do Porto, Portugal

A New Transla t ion Algor i thm f rom L a m b d a Calculus into C o m b i n a t o r y Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 359 Sabine Broda and Luis Damas LIACC, Universidade do Porto, Portugal

XIII

T a b l e o f C o n t e n t s - - P o s t e r s

In te r lock ing Mul t i -Agen t and Blackboard Archi tec tures . . . . . . . . . . 371 Bernhard Kipper DCS, University of Saarbriicken, Germany

A Mode l Theo ry for Paracons i s t en t Logic P r o g r a m m i n g . . . . . . . . . . 377 Carlos Viegas Dams and Luis Moniz Pereira CRIA, and DCS, Universidade Nova de Lisboa, Portugal

P r o m o t i n g Software Reuse T h r o u g h Explicit Knowledge R e p r e s e n t a t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 387 Carmen Ferns Pedro Antonio Gonzs and Mercedes GSmez-Albarr~n Universidad Complutense de Madrid, Spain

Efficient Learn ing in Mul t i -Layered Pe rcep t ron Using the Grow-And-Lea rn Algo r i t hm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397 Gildas Cherruel, Bassel Solaiman and Yvon Autret Univ. de Bretagne Occidentale, and TNI, and ENSTB, France

An Non-Diff ident Combina tor ia l Opt imiza t ion Algor i thm . . . . . . . . . 403 Gilles Trombettoni, Bertrand Neveu, Pierre Berlandier, Maria-Cristina Rift and Mouhssine Bouzoubaa INRIA-CERMICS, France

Model l ing Diagnosis Systems wi th Logic P r o g r a m m i n g . . . . . . . . . . . 409 Iara de Almeida M6ra, Jos~ Jfilio Alferes CRIA, U. Nova de Lisboa, and DM, U. ]~vora, Portugal

Agreemen t : A Logical Approach to Approx ima te Reasoning . . . . . . 419 Luis M. M. Custddio and Carlos A. Pinto-Ferreira ISR, Technical University of Lisbon, Portugal

C o n s t r u c t i n g Extens ions by Resolving a Sys tem of Linear Equa t ions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429 Messaoudi Nadia Universitd Aix-Marseille II, France

P re sen t i ng Significant In fo rma t ion in Exper t Sys tem E x p l a n a t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435 Michael Wolverton Daresbury Rutherford Appleton Laboratory, UK

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A Cognit ive Model of P rob lem Solving wi th Incomple te In fo rma t ion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441 Nathalie Chaignaud LIPN, Universitd Paris-Nord, France

Fi l ter ing Software Specifications W r i t t e n in Na tura l Language . . . 447 Nfiria Castell and Angels Hern~ndez Universitat Polit~cnica de Catalunya, Spain

Pars imonious Diagnosis in SNePS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 457 Pedro A. de Matos and Jogo P. Martins DEM, Technical University of Lisbon, Portugal

Syntact ic and Semant ic Fi l ter ing in a Char t Parser . . . . . . . . . . . . . . . 465 Sayan Bhattacharyya, Steven L. Lytinen University of Michigan, and DePaul University, USA

GA Approach to Solving Mul t ip le Vehicle Rou t ing P rob l em . . . . . 473 Slavko Krajcar, Davor Skrlec, Branko Pribicevic and Snjezana Blagajac Faculty of Electrical Eng. and Computing, Croatia

Mult i level Ref inement P l ann ing in an In terva l -Based Tempora l Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482 Werner Stephan and Susanne Biundo German Research Center for AI, Germany