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Introduction to System DevelopmentIntroduction : Have you ever seen newspaper headlinessi mi l ar to the following ?• IRS Computer Audit Record Number of Tax Returns• Computer Skills Needed for Today’s Jobs• Computer Failure Halts ShuttleLaunch• Wall Street Computer Handle Growing Stock Trading VolumeNewspaper headlines are not our only view of today’swidespread use of computers. The use of computers in today’sworld is commonplace. We take computers for granted andexpect them to work perfectly; that is, to be reliable, fast,accurate, and easy to use.

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Systems and procedures As it conducts its business, a company performs many

functions in a specified manner.• A procedure is defined as the series of steps followed in a regular, specified order to accomplish one end result. One procedure for company is the writing of employee payroll checks, and a second procedure is the filling of customer orders.• A system is defined as a set of procedures used to accomplish specific results.

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Example Systems• Student Record Management System

– A computerised system that manages information concerning courses on offer at Brookes and Students registered to take one of more of those courses.

• Library Loan System– A computerised system that manages the issuing

and recall of library books.

• Car Park Management– A paper (form)-based system for managing the

allocation of parking spaces to visitors

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Examples (cont.)• Traffic Management System

– A system of interconnected components (roundabouts, traffic light, calming devices) to manage the flow of traffic through …

• Chemical Process Control– A system based on feedback and control to

manage the manufacturing of ….

• The Respiratory System– The physiological system which enables the act or

process of breathing in animals

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Key Ideas

• Many failed systems were abandoned because analysts tried to build wonderful systems without understanding the organization.

• The primarily goal is to create value for the organization.

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Simple system model

Data processing Information

input - manual output - computerize

- knowledge

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System inputs are called data, and system output are calledInformation.

Data : defined as raw facts an d figures, are the raw materials of the system.

Information : defined as data processed for someone’s use, represents the finished goods of the system.

The objective of processing is t o ensure the validity of the incoming data and to convert valid data into timely and accurate information.

A system may be called an information system, anapplication, or an application system.

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Information systemcomponents

Data

PeopleProcedureHardwareSoftwareFiles

Information

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People - include both management and end usersProcedures - the tasks performed by all the people

Hardware - computers, scanners, printer, and noncomputer equipment

Software - system software- DOS, Windows, andUNIX

- application softwareFiles - the retained data is stored in files and

databases on computer An information system is the collection of data, people,

procedures, hardware, software, files, and information required to accomplish an organized set offunctions.

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Data, Information and Knowledge

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Wisdom

"Wisdom is not a product of schooling but

of the lifelong attempt to acquire it.“

Albert Einstein

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Business informationsystems Each business organization sells specific products or

services and has specific goals, methods, and information system requirements that are set in the organization’s

underlying corporate culture. A company’s corporateculture is the set of beliefs, rules, traditions, values, and

attitudes that give a company its atmosphere or personality and govern its way of doing business. In order to create an

effective information system for a company, you must understand the information system’s requirements and the

company’s goals, methods, and corporate culture.

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Although there are a variety of types of business organizations in operation in the world today, companies

are generally classified into two basic types:• -Industrial, or production oriented companies, which

produce, sell, and distributegoods• service companies, which sell and distribute goods,

services, or information The total business information system of acompany

normally consists of a series of subsystems, many of which are common to all businessorganizations.

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PurchasingSystemsVendor SelectionOrderingElectronic BuyingReceivingInspectionAccounts Payable Human Resource

SystemsEmployee SelectionCompensation AnalysisBenefits ProjectionsEmployment HistorySkills Inventory

ProductionSystemsRaw MaterialsProduction SchedulingFinished Goods CostingPackagingShipping and Distributing

FinanceSystemsGeneral LedgerPayrollCost AccountingBudgetingPortfolio Analysis

MarketingSystemsCustomer Order EntryPricingSales AnalysisAdvertising PerformanceForecasting

ReceivablesSystemsCustomer Invoicing and BillingCash ReceiptsAccounts Receivable

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Four characteristics of business information systems help to define their complexity.

1 . Information systems are r el at ed t o ot heriiiiiiiiiii iiiiiiii

2 . A boundary between two systems is where one system ends and the other system begins.

3 . In addition to the common business information systems, there are many specialized information system s.

At a school, specialized information systems handle cla ss registration, class room scheduling, student grading, st udent

loans, and transcriptprocessing.

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4 . Large and small companies in the same industry have significant differences in their information system

iiiiiiii iiiii

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Types of information systems The types of information systems that use a computer

fall into six broad categories:• Operation systems (transaction processingsystem)• Management information systems (MIS)• Decision support systems(DSS)• Executive information systems (EIS)• Expert systems (ES) or Artificial intelligence (AI)• Office automation systems(OAS)• The integration of i nf or mat i on syst ems

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Organization levels Information is a company asset, as are employee,

equipment and buildings, materials, and money. Information systems exist to provide this information

asset to people in the organization. Information requirements vary widely, depending on the person’s

responsibilities and position within the company. All companies organize in the way shown in figure; operational personnel report to lower management, who

report to middle management, who report to topmanagement.

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TopManagement (Strategic) MiddleManagement (Tactical) LowerManagement

(Supervisory) Operational Personnel

(Functional)

Organizati on levels

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Organization Responsibility Decision Information Systems Level Making Requirements

- Top Develop long range Unstructured Executive information systems Management goals, plans and MIS summaries

strategies Decision support systems Office automationsystems

- -Middle Develop short range Semi struct ured MIS summaries and exceptions Management goals, plans, and Decision support systems

tactics Office automation systems

- - Lower Develop day to day Structured Operational systems details Management plans and supervise Some MIS summaries and

operational personnel exceptions Office automation systems

Operational Perform routine Structured Operational systems details Personnel function Expert systems

Office automation systems

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ESSGDSS CSCWS ES, DSS,

MIS KWS,

OAS

TPS

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Integrating Technologies for Systems 1 Ecommerce Applications and Web Systems- Increasing user awareness of the availability of a service, product, industry, person, or group.- The possibility of 24-hour access for users.

2. Enterprise Systems- Service-oriented architecture (SOA)- Enterprise resource planning (ERP)

3. Systems for Wireless and Mobile Devices4. Open Source Software (OSS)

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ESSGDSS CSCWS ES, DSS,

MIS KWS,

OAS

TPS

Wireless Systems

Enterprise Systems

Ecommerce and Web Systems

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Information systems department The structure of the informatio n systems department

varies among companies, as d oes its name and its placement within the organization. Director

InformationSystems

ManagerOperations

ManagerTechnicalSupport

ManagerApplications

ManagerInformationCenter

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Maxim

The organization that has

the best information,

knows where to find it,

and can utilize it the quickest wins.

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Data Quality Factors

Accuracy Whether the value of each item of data is

correct

Timeliness Whether the data are up-to-date

Consistency Whether the data in one part of the database

have a common, appropriate set of controls to related concepts stored elsewhere

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Data Quality Factors

Transparency of meaning Whether the context for the data is clearly and

commonly understood by all those with a legitimate interest

Availability Whether the people who need the data can

actually access it

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Systemdefinition : set of interrelated and interacting elements that work together to

accomplish specific purposes.structure : inputs, processes, outputs, feedback, environment, decision maker.subsystem : a system within a system.system performance : effectiveness (doing the right thing),efficiency (doing the

thing right), cost, complexity, and control.

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Effectiveness and Efficiency

Two Major Classes of Performance

Measurement

• Effectiveness is the degree to which goals

are achieved Doing the right thing!

• Efficiency is a measure of the use of inputs

(or resources) to achieve outputs

Doing the thing right!

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Inputs Raw materials

CostsResources

ProcessesProceduresProgramsToolsActivitiesDecisions

OutputsPerformancesConsequences

Finished products Services delivered

Decisionmaker

Stockholders BanksVendors

Customers GovernmentEnvironment

Com

peti

tors

Wea

ther

conditio

ns

System boundary

Feedback

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Inputs are elements that enter the system

Processes convert or transform inputs into

outputs

Outputs describe finished products or

consequences of being in the system

Feedback is the flow of information from the

Output to the decision maker, who may modify

the inputs or the processes (closed loop)

The Environment contains the elements that lie

outside but impact the system's performance

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Modeling asystem Model = abstraction of reality

- narrative models- physical models- schematic models- mathematical models

F = X2 + Y2

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Systems Analysis and Design: What is it?

•Systems analysis: the systematic study of the information needs and problems of some organizational domain in order to recommend improvements and specify the business requirements for the solution.

•Systems design: the specification of a technical, computer-based solution for the business requirements identified in a systems analysis

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Systems Analysis and Design: Why is it?

• Many information systems fail, because of: lack of reliability lack of usability not what the users wanted incompatible with other systems

• SA&D addresses all but the first problem

• SA&D is also long-term approach to ensure the overall effectiveness of IT in the organization

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A systems analyst studies the information problems and needs of an organization to determine how to best solve the problems and accomplish improvements using information technology.

–improved business processes

–improved information systems

–improved computer applications

Systems Analysis and Design: Who is it?

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Roles of the Systems Analyst :

–Consultant (outsider)–Supporting Expert (insider)–Agent of Change (shaker)

Systems Analysis and Design: Who is it?

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Systems Analysis and Design: Where is it?

Not just for businesses! – non-profit organizations

– government agencies

– educational institutions

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• The systems analyst is a key person analyzing

the business, identifying opportunities for

improvement, and designing information

systems to implement these ideas.

• It is important to understand and develop

through practice the skills needed to

successfully design and implement new

information systems.

Key Ideas

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•Analytical•Technical•Management•Interpersonal

Qualities and Skills of a Systems

Analyst

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• Required skills and background• Working Knowledge of I nformation Systems and

Technology• Computer Programming Experience and Expertise• General Business Knowledge• - Problem Solving Skills• Interpersonal Communic ations Skills• Interpersonal RelationsSkills• Flexibility and Adaptability• Character and Ethics• Systems Analysis and D esign Skills

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Who is system analyst?

User System analyst Programmer

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General System Model o f the Firm

Physicalresources Input

resourcesOutputresources

PhysicalresourcesTransformation

process

Management

Standards

InformationProcessor

ENVIRONMENT

InformationDecisions

Information anddata

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ห์น�าท�'ของผู้��บร�ห์าร (โดย พริะเมธี"ธีริริมาภริณ์�)หนั�าที่"&ของนั�กบริหาริปริากฎอย�(ในัค)าจำ)าก�ดความที่"&ว(า

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2 .) การิจำ�ดองค�การิ (Organizing )หมายถึ,งการิก)าหนัดต)าแหนั(งสำายบ�งค�บบ�ญช้าในัองค�การิว(าม"ต)าแหนั(งอะไริบ�าง แต(ละต)าแหนั(งม"อ)านัาจำหนั�าที่"&อย(างไริ ใคริสำ�&งการิใคริเป9นัต�นั

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3.) นัสำสำยสำ�มป>นัโนั หมายถึ,ง พ,&งพาอาศิ�ยคนัอ1&นัได�เพริาะเป9นัคนัม"มนั�ษยสำ�มพ�นัธี�ด" นั�กบริหาริที่"&ด"ต�องผู้�กใจำคนัไว�ได�ค�ณ์ล�กษณ์ะข�อนั"8ตริงก�บภาษาอ�งกฤษว(า Human Relation Skill ค1อ ความช้)านัาญด�านัมนั�ษยสำ�มพ�นัธี�

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Who Are the Players in Systems Development?

• User(s)• Business manager(s)• Steering committee• Application programmers• System programmers• Database, network, and other technology specialists• Security / auditing staff• Human factors experts• Documentation specialists