1-* Prentice Hall, 2007Chapter 1:The Object-Oriented Systems Development EnvironmentObject-Oriented Systems Analysis and DesignJoey F. George, Dinesh Batra, Joseph S. Valacich, Jeffrey A. Hoffer

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1-* Prentice Hall, 2007Chapter ObjectivesAfter studying this chapter you should be able to:Define information systems analysis and design.Explain the basics about systems.Describe the information systems development cycle (SDC).Describe TPS, MIS, DSS, and ES/EIS.Describe the role of systems analyst.Recount the evolution of system development methodologies.

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1-* Prentice Hall, 2007What Is Systems Analysis and Design?The process of developing and maintaining an information systemMain goal improve organizational systems via software to help accomplish business tasks efficiently and easilyRequires knowledge of:Organizations objectives, structure, processesHow to exploit information technology for advantage

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1-* Prentice Hall, 2007Core ConceptsMajor goal of systems analysis improve organizational systemsDevelopment/acquisition of application softwareOther elements of IS hardware, system software, documentation, training materials, job roles, controls and security, people

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1-* Prentice Hall, 2007What Is a System?A group of interrelated procedures used for a business function, with an identifiable boundary, working together for some purpose.

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1-* Prentice Hall, 2007Characteristics of SystemsComponents irreducable or aggregate parts of a system (also called subsystems)Interrelationships associations and dependencies between components of a systemBoundary divides system from environmentPurpose goal or function of a systemInterfaces points of contact between system and environmentInputs data from environment to systemOutput data from system to environmentConstraints limit to what the system can accomplish

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1-* Prentice Hall, 2007Important System ConceptsDecomposition breaking down a system into smaller constituentsModularity the result of decomposition; parts of a systemCoupling extent of dependencies between subsystemsCohesion extent to which a subsystem performs a single function

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1-* Prentice Hall, 2007Transaction Processing System (TPS)Automate the handling of data for business activities or transactions

Goal: improve transaction processing by increasing speed, enhancing productivity, improving efficiency and accuracy

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1-* Prentice Hall, 2007Management Information System (MIS)Use raw data from TPS systems, and converts them into meaningful aggregate form, resulting in summary reports

Goal: provide the information that helps managers in their jobs

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1-* Prentice Hall, 2007Decision Support System (DSS)Combine databases, mathematical or graphical models, and interactive user interfaces or dialogues allowing users to manipulate data and models

Include what-if analyses, executive information systems, data warehouses, knowledge management systems

Goal: support decision-making with unstructured and unpredictable problems

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IS Department Organization Chart1-* Prentice Hall, 2007

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IS Components1-* Prentice Hall, 2007Chief information officerChief Technology officerOperation groupDevelopment groupOutsourcing relation groupData administration staff

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1-* Prentice Hall, 2007Characteristics of Sucessful TeamsDiversity of backgrounds, skills, and goalsTolerance of diversity, uncertainty, and ambiguityClear and complete communicationsTrustMutual respect and putting personal interests second to the teamReward structure that promotes shared responsibility and accountability

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1-* Prentice Hall, 2007The Role of the Systems AnalystSkills required: analytical, technical, managerial, interpersonal

Fluency in systems thinking

Liaison between users, programmers, and other systems professionals

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1-* Prentice Hall, 2007Evolution of System Development MethodologiesSDLCSystems Development Life CycleStructured Analysis and DesignUse of Data Flow DiagramsData-Oriented MethodologyUse of Entity Relation DiagramsObject-Oriented MethodologyUse of Unified Modeling Language (UML) DiagramsAgile MethodologiesAdaptive, people-oriented approach

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1-* Prentice Hall, 2007Systems Planning and SelectionAnalyze and arrange organizations information needs, identify and describe potential project, determine system scope, and provide a business case for continuing with the project

Feasibility analysis: determine economic and organizational impact of the system

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1-* Prentice Hall, 2007Systems AnalysisThorough study of organizations current system and processes, determination of system requirements, structuring requirements, generate alternative design strategies.Use of UML for system modelingGoal: describe what needs to be done

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1-* Prentice Hall, 2007Systems DesignTranslating alternative solution generated by analysis phase into detailed logical and physical system specifications.Logical design: not tied to any hardware or software platformPhysical design: specific programming languages, databases, architecturesGoal: identify how the task will be accomplished

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1-* Prentice Hall, 2007System Implementation and OperationInformation system is coded, tested, and installed, and undergoes periodic corrections and enhancements

Goal: provide a fully operational system

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1-* Prentice Hall, 2007Key Differences Between Structured and Object-Oriented Analysis and Design

StructuredObject-OrientedMethodologySDLCIterative/IncrementalFocusProcesssObjectsRiskHighLowReuseLowHighMaturityMature and widespreadEmergingSuitable forWell-defined projects with stable user requirementsRisky large projects with changing user requirements

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1-* Prentice Hall, 2007Construction is the hardest part

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1-* Prentice Hall, 2007InceptionDefining the scope, determining the feasibility, understanding user requirements, preparing a software development plan

Relatively short, low resource requirements

Focus on planning and analysis

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1-* Prentice Hall, 2007ElaborationDetailed user requirements and baseline architecture is established

Fairly long, but not high in resource demand

Focus on analysis and design

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1-* Prentice Hall, 2007ConstructionCoding, testing, and documenting code

Longest and most resource-intensive

Focus is on implementation tasks

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1-* Prentice Hall, 2007TransitionSystem is deployed and users are trained and supported

Short-term, but resource-intensive

Focus is on installation, training, and support

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