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PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 © John Wiley & Sons, Inc. All rights reserved. Slide 1 INTRODUCTION Overview of Systems Analysis

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INTRODUCTIONOverview of Systems Analysis

Slide 1

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Key IdeasMany systems failures were because analysts tried to build wonderful systems without understanding the organization and applying a systematic approach.

Slide 2

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Key IdeasThe 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.Slide 3 PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Types of Information SystemsTransaction Processing Systems Management Information Systems Decision Support Systems Expert Systems Development of these systems require a good understanding of business processes and dataSlide 4 PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Systems Development Lifecycle Approach The projectMoves systematically through phases where each phase has a standard set of outputs Produces project deliverables Uses deliverables in implementation Uses gradual refinement and an iterative approach

Slide 5

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Project PhasesPlanningWhy build the system?

AnalysisWhat will the system be?

DesignHow will the system work?

ImplementationSystem deliverySlide 6 PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

PlanningIdentifying business value Analyze feasibility Develop work plan Staff the project Control and direct project

Slide 7

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

AnalysisAnalysis Information gathering Process modeling Data modeling

Slide 8

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

DesignPhysical design Architectural design Interface design Database and file design Program design

Slide 9

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

ImplementationConstruction Installation

Slide 10

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Processes and DeliverablesProcess Planning Product Project Plan

Analysis

System Proposal

Design

System Specification New System and Maintenance Plan

Implementation

Slide 11

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

What Is a Methodology?A formalized approach or series of steps Writing code without a wellthought-out system request may work for small programs, but rarely works for large ones.

Slide 12

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Structured DesignProjects move methodically from one to the next step Generally, a step is finished before the next one begins

Slide 13

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Waterfall Development Method

Slide 14

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Pros and Cons of the Waterfall MethodPros Identifies systems requirements long before programming begins Cons Design must be specified on paper before programming begins Long time between system proposal and delivery of new system

Slide 15

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Alternatives to the SDLCRapid Application Development (RAD) Prototyping

Slide 16

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Rapid Application DevelopmentCritical elementsCASE tools JAD sessions Fourth generation/visualization programming languages Code generators

Slide 17

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

How Prototyping Works

Slide 18

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Object-Oriented Analysis and DesignAttempts to balance emphasis on data and process Uses Unified Modeling Language (UML) for diagrammingUse-case Driven Architecture CentricFunctional, Static, and Dynamic views

Iterative and IncrementalSlide 19 PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

Key ElementsClasses -- template to define objects Instances -- specific examples of classmembers

Objects -- building block of the system Attributes -- describe data aspects of theobject

Methods -- the processes the object canperform

Messages -- instructions sent to or receivedfrom other objectsSlide 20 PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

A Class and Its ObjectsInstantiated Objects of the Class ClassPATIENT -Name -Birthdate -Phone Number +Insert ()() +Delete ()() Methods PATIENT 1: TOP PACKAGE: PATIENT -Name = Teresa Marks -Birthdate = March 16, 1975 -Phone number = 314-997-3456 Attributes

PATIENT 2: TOP PACKAGE: PATIENT -Name = Mel Bourne -Birthdate = May 11, 1965 -Phone number = 314-997-3219

Slide 21

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

The Key to ReusabilityInformation hiding is the principle that only information required to use the object is available outside the object Encapsulation is the mechanism that combines data and processes in a single objectSlide 22 PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

UMLUnified Modeling Language The full UML provides 9 separate diagramming techniques

Slide 23

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

SummaryThe Systems Development Lifecycle consists of four stages: Planning, Analysis, Design, and Implementation There are two major development methodologies: the waterfall method, RAD/Prototyping

Slide 24

PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.

SummaryThere are six major elements in ObjectOriented design: classes, objects, instances, attributes, methods, and messages. Encapsulation, Inheritance, and Polymorphism are also important objectoriented concepts There are five major team roles: business analyst, systems analyst, infrastructure analyst, change management analyst and project manager.Slide 25 PowerPoint Presentation for Dennis, Wixom & Tegardem Systems Analysis and Design Copyright 2001 John Wiley & Sons, Inc. All rights reserved.