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SYSTEMS ANALYSIS

AND

DESIGN

INTRODUCTION

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Systems Analysis and Design

is the process people use tocreate (automated)information systems

Systems

Analysis& Design

InformationSystem

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Information Systems Engineering!Software Engineering!

Information Systems DevelopmentSystems Engineering!

Systems Analysis and Design!

Other names...!

Which

one?

Is there an official name?

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A title given to a person who studies theproblems and needs of an organization

looking for improvement opportunities.

Systems Analyst

Other names:

Software Engineer Systems Engineer Software Developer Programmer/Analyst

Nerd or Hacker! (joking!) 4

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An idea Analysis Design andImplementation

CompletedInformation

System

SYSTEMS ANALYSIS ANDDESIGN: A Condensed (Informal)

Perspective

Time 5

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DESIGN: A Complete (Formal)

Perspective

Systems Planning

Systems Analysis

Systems Design

Systems

Implementation

Systems Evolution

Planning

Evolution

ImplementationDesign

Analysis

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System

Natural Fabricated

InformationSystems

Others

AutomatedInformation

Systems

Others

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Name & Address Book

CD Collection

Course Registration

Reservations

Student Grades

Payroll

ATM machine & Banking in General

Check-Out Counters at Retail Stores

Order Fulfillment - Mail or Web Ordering

Manufacturing

Securities Portfolio Management

Space Shuttle Flight

Election Results

Video Games (Arcade and Home)

Business problems come in all sizes and s

Examples:

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A SYSTEM is a set of:

interrelated components

working together

for a common purpose

System

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SYSTEM

boundary

inputs

outputs

processing

controls

feedback

A Generic System Model(with Six Components)

Examples: Automobile

Student Registration Syste

Others... 10

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System Model Hierarchy

Water Vehicles

Cruise Ship

Staterooms

Suprasystem

System

Subsystem

bigger

smaller

Template Example

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An INFORMATION SYSTEM is:

a type of fabricated system

used by one or more persons

to help them accomplish some task or assignment

they have

people

procedures

data

An Information System:

includes the 3 aspects of a

system supports policies & procedures

has three additional

components - data, people,

procedures - in addition to the six 12

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An AUTOMATED INFORMATION SYSTEM IS:

a type of fabricated system

used by one or more persons

to help them accomplish some task or

assignment they have

utilizes hardware and software in

addition to data, people, procedures

plus all the aspects of a system

people

procedure

data

software

hardware

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DATA - input, output, or already stored

electronically

FUNCTIONS - transformations or actions taken

BEHAVIOR - the observable effects from

DATA FUNCTIONS

BEHAVIOR

An AUTOMATED INFORMATION SYSTEMhas three basic characteristics toconsider:

(Plus the six system components: input, output, processing, control, feedback a

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Systems Analysis and Design

is the process people use tocreate (automated)information systems

people

procedures

data

software

hardware

SA&D

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The people who do SYSTEMS ANALYSIS and

DESIGN produce information systems that are:

used internally within the organization

sold commercially via mail/web order or retail

store

imbedded in products

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Initially, problem domains (areas) tend to have poorly defined

BOUNDARIES

Problem domain SOLUTIONS are artificial

Problem domains are DYNAMIC

Problem domain solutions usually require INTERDISCIPLINARY

knowledge and skills

Systems Analysts KNOWLEDGEBASE is continually expanding

Systems Analysis and Design is a highly COGNITIVE activity

Working with PEOPLE

What makes Systems Analysis andDesign a difficult activity?

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Systems Analysts interactions with people during Systems Analysis

SYSTEMS

ANALYST

Users*Steering

Committee*

Vendors

Programmers& Tech. Staff

DatabaseAdministrators

Managers*

* = Stakeholders

Systems Analystmay be acting asa Project Managerfor some of theseinteractions.

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Studies the problems and needs of an

organization looking for improvement

opportunities for:

increasing revenue/profit

decreasing costs

improving quality of service

What does a Systems Analyst do?

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Effective and efficient:

CAPTURE of input data

PROCESSING & STORAGE of data

DELIVERY of timely and accurate

What is a Systems Analyst responsible

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Requirements Specification

(3)

General Model of Information Systems Development (Partnership)

Stakeholder

Information

Technology

Staff

Analysis

Design

andImplementation

Requirements

(1) Continued

Involvement

(5)

Information

System (6)

Problem

DefinitionSkills (2)

Problem

SolutionSkills (4)

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Systems Analysis and Design Activities and Deliverables

ANALYSIS

Activities:

Systems Planning

Feasibility Study (optional)

Requirements Determination

Conceptual Design User Acceptance

Prototyping (optional)

Deliverables:

Requirements Specification

Prototype (optional)

DESIGN

Activities:

Deliverable:

Physical Design

Prototyping (optional)

Software Construction/Purchase

User Documentation - Deliverable

Testing

Training

User Acceptance

Conversion

Implementing the system

Information System

Project Management

Project Documentation - Scaffolding

Two (2) additional on-going activities:

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Labor intensive

Smallest team = you

Next smallest team = you and one other (user)

Average team = several systems analysts and

users

Articulation of the business problem is difficult

Systems Analysis and Design Project Observ

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Problems - something needs to be

fixed

Opportunities - good deals

Directives - do itor else

Where Do Systems Analysis andDesign Projects Come From?

... and are bounded by Constraints

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Planning

Feasibility Study (optional)

Requirements Determination

Conceptual Design

Physical Design

Construction and/or Purchase(prototype)

Training

Conversion - old to new

Implementation

-

SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC

Analysis

Des

ignand

Implementation

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Planning

Feasibility Study

Requirements Determination

Conceptual Design

Physical Design

Conversion

Training

Implementation

Evolution

Iterative SDLC

Risk Analysis

Spiral SDLC

SDLC Activities

Verification/Test

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29Boehm, 1988

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The system is for the user

A Work Breakdown Structure should be used (ie.,

SDLC)

Systems analysis and design is iterative and

overlapping

Information systems are capital investments for the

business

Project manager may have the authority to cancel a

Principles to Guide Systems Analysis & De

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QUITTING TIME

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