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BIS 1103

SYSTEMS ANALYSIS AND

DESIGN

Lecturer: Paul Katongole

Email: [email protected]



Course Objectives

At the end of the course students should be able to:

1. Apply Information systems concepts to an

Information System problem.2. Understand and apply Systems Development

Life Cycle concepts.

3. Document the overall structure of data flow for

a business problem.

2BIS 110: Systems Analysis and Design



Objectives (contd)

4. Document requirements & design of

computer generated outputs.

5. Document computer programmingspecifications for a system.

6. Organize & present the documentation for

a system in a technical report.




Course outline

The topics covered include:

1. Course overview

2. Introduction to Information Systems Analysis and Design.

3. The System Development Lifecycle

4. Preliminary Investigation and Feasibilitystudy

5. Requirements determination




Course outline contd

6. Information gathering techniques

7. System analysis tools and techniques

8. System design9. System Implementation, Evolution and

Review

10.Information systems project management




Pedagogy

Teaching / Learning approach :

Classroom lectures

Group discussions

Take home assignments which will form

part of the coursework.




Assessment

Students are evaluated through:

± Coursework (40%) consisting of anassignment and 2 tests

± Final examination (60%)




Course Policies

Assignments Due Dates.

Late submissions shall not be accepted

No make up test will be given




Course overview

This course introduces the theory &

application of Information Systems

Analysis and Design.

Describes Information systems & the

Systems Development Life Cycle

Presents tools & techniques for

documenting Information systems




Course overview (cont¶d)

Explains the classical and structured tools

for describing data flows, data structures,

process flows, file design, input and

output design and program specification

The primary theme of the course is the

use of systems analysis and design

techniques to develop and documenteffective computer based Informationsystems.




Course overview cont¶d

Systems analysis & design are primarily

done by the Systems analyst.

Systems analysis, design, andimplementation are processes used by

professionals to develop and maintain

Information systems.




Introduction

Systems analysis

The study of an organization's

problem or situation & the specification of business

requirements for an improved system.

Systems design

Detailed specification of a computer based

solution to the business requirements.

The design includes the programming

specifications.




Systems Analysis and Design

SAD includes all activities performed toproduce an automated IS.

Covers the entire systems developmentprocess from:

Planning to implementation,

maintenance, and evolution.




Why analysis and design?

Successful IT projects follow a systematic

³analysis and design´ process in order toimprove chances of success in terms of;

Quality

Time,

Costs




Systems and subsystems

System:

A set of interrelated interacting components thatwork together to achieve specific results.

An effective system is Syner gistic e.g. a hometheatre system.

Business systems are composed of:People, facilities, equipment, materials and

methods of workthat function together to provide goods or services




Subsystems

Exist where main system becomes

complex

Example:

Manufacturing

Textile industry where an input isprocessed to produce an output which

becomes input to another




Information system

A collection of interrelated componentsworking together to collect, retrieve, process,

store and disseminate information for the

purpose of facilitating planning, control,

coordination, analysis, and decision making inbusinesses & organisations.




Information system

Main types of Information Systems

1. Transaction Processing System (TPS)

2. Office Automation Systems (OAS) 3. Management Information System (MIS)

4. Decision Support System (DSS)

5. Strategic Information System (SIS) or (ESS)

6. Expert System (ES)

BIS 110: Systems Analysis and Design 18



Controls routine daily activities of an organization

Typically large volumes of data.

A transaction is an event that affects theorganization

Transaction processing cycle includes:

± recording,

± processing, ± updating,

± output, report

1. Transaction processing system




TPS contd

Examples of transactions include ...

receive payment

place order

refund purchase




2. Office Automation Systems (OAS)

At the ³knowledge´ level of an

organization

Use information for analysis Familiar aspects of OAS include:

±word processing, desktop publishing

±spreadsheets, scheduling

±voice mail, electronic mail




Deals with summary Information from TPS

Exception conditions where special action

is required require closer attention andare reported.

3. Management Information System




4. Decision Support System (DSS)

Strategic Planning

Set long-term goals

Uses internal results from TPS and MIS Also uses external (statistical) data

Build model for future state of the business

Group Decision Support System (GDSS) ±Uses group problem solving




5. Str ategic Information System (SIS) or

Executive Support System (ESS) Aims at giving a firm competitive advantage

within an industry

Michael Porter identified the following ways:

± Build barriers against potential competitors. ± Enhance customer loyalty.

± change the basis of competition within anindustry

± Develop new products

Example: American Airlines - first to createon-line ticket reservation system




6. Expert System (ES)

Part of the field of Artificial Intelligence

Computer system which guides user through tasks requiring special knowledge

Contains ³knowledge base´ which includesboth data and decision rules

Examples:medical diagnosis, oil exploration, life

support systems etc




Organizational Levels

Four organizational levels

Operational personnel

Lower management

Middle management

Top management

Responsibilities, decision-making styles, and

information system requirements

Empowerment of operational personnel26BIS 110: Systems Analysis and Design



Or ganisation Levels and IS requirements




Or ganisation levels and IS requirements




Or ganizational goals and information systems

Examples of organizational goals:

± Maximize profit

± Increase market share or sales volumes

± Operate in an environment-friendly manner etc

Purpose of an Information system is to helpachieve organizational goals

Some times technology / computers can assist.

Note: Need to draw system a boundary since itinteracts with its environment




A boundar y (scope)

What is the perimeter or border of thesystem ± elements, features, options, that

will be included in the system.

What is the area under investigation?

What is the boundary of the system?

What parts of the organization are off limits?




Components of an Information system

Input - data, the raw facts

Process - transform data into usefulinformation

Output - product or result

Feedback - for quality control, evaluateresults

Ad justments - where corrections arenecessary




.

BIS 110: Systems Analysis and Design 32

Source Processing Destination

Control

Ad justments

Feedback

InputOutput

Components of an information system-a gener al example



Components of an Automated Information system

It is made up of :

Hardware,

Software, Data

Procedures

People,




An Automated Information System

. Procedures

Data

Hardware

People

Software




Char acteristics of an Information System

Data

Either

± Input via some data entry device, ± OR already in the system and stored on

a storage device, or

± Displayed or printed on an outputmedium.




Char acteristics of an Information System

Function ( process, method ) ± is a

transformation or action taken by the IS.

±Functions carry out and enforcebusiness policies, rules, and

procedures.

Behaviour ± is the observable effects of a

request.




Data: input, stored, or output

Function: business activity performed

Behaviour: the observable effects of a request

Basic Char acteristics of an IS

Data

Behaviour

Function




The Systems Development Process (Overview)

The system development process

comprises of :

1. Techniques2. Methods

3. Strategies.




Techniques, methods and str ategies




Techniques

Are at the lowest level of the process.

Are designed to do a particular task within the

analysis and design process.

Several techniques may be applied for a given

method / methodology / approach.

Examples include:

± Data flow diagrams, Flow charts, Logical datastructures, Context diagrams, Decision tables,

Gantt charts, Tree diagrams.




A system analysis method embodies a

number of techniques each chosen for its

appropriateness to a particular task withina method / methodology.

Note: Several methods May be combined

for a given computer systems developmentstrategy.

Methods / Methodology




Examples of methods / methodologies:

1. Structured Systems Analysis & Design

Methodology.

2. Jackson Structured programming(JSP)

3. Soft Systems Methodology.

4. Object Oriented Methodology.5. The Traditional SDLC

6. Prototyping

Methodologies




SA & D takes a much broader

perspective and focuses on:

1.

Systems Planning ± performingplanning and initial feasibility activities to

determine which IS projects take priority

over others.

The Systems Development Process

(Overview)




2. Systems Analysis ± understanding and

documenting the requirements of a

specific problem domain.

A problem domain refers to the

business problem or function being

planned, analysed, designed, and

ultimately implemented as an automatedIS.





3. Systems design ± designing an

appropriate technical solution for the

problem domain based on the

documented requirements from SA.

4. Systems Implementation ± constructing,

testing and installing the information

system and having the users use the IS.





The Systems Development Process

(Overview)

5. Systems Evolution ± maintaining

and enhancing an IS so that it

continues to meet the needs of thebusiness.




The System Analyst

Performs Systems Analysis

Usually employed in the InformationSystems Department

Has Wide ranging skills




The system analyst..(cont)

A System Analyst studies the problems

and needs of an Organisation.

To determine how people, methods, andcomputer technology can best

accomplish improvements for the

business.




1.Investigate how information is used, handled and

manipulated in an organization.

2.Identify inefficiencies and ineffectiveness in the

current system used by the organization e.g.delays, high operating costs, huge clerical

effort and health hazards.

3.Analyze the results of the investigation that will

lead to designing the new system.

Role of a Systems analyst




Role of a systems analyst (cont)

4. Design a specification of a new

system which overcomes the

inefficiencies and meets theorganization objectives.

5. Oversees the process of testing

during the testing of the system.




Role of a systems analyst (cont)

6. The analyst acts as a f acilitator .

±He / She interfaces among many

different types of people and ± facilitates the development of

computer applications through

these people.




Stakeholders of an information system

.

Systems

Analyst

Vendors

Steering

Committee

Users

Managers

Database

Administrators

Programmers

& Technical

Staff




Stakeholders of an Information System

Note. These teams in the diagram will be

created and disbanded as projects are

started and completed or cancelled.

The Analyst may be the only individual

who sees well the big picture of the

system.




Tasks of a systems analyst

Include;

Investigation

Planning Understanding

Communication

Documentation




Qualities of a Systems analyst

1.Working knowledge of IS Techniquesand Technology.

2.Computer Programming Knowledge

3.Problem-solving skills (creativity)

4.Interpersonal Relations skills

(confidence, persistent, patience)5.Interpersonal communication skills

6.Ongoing interest in updating one¶s

knowledge in IT.




Systems Analyst skills - Behaviour al &Technical

Diplomacy Being able to say "no" without being " blunt; displaying tact indealing with others.

Interviewing Asking the right questions in order to obtain the informationneeded.

Directing Giving instructions and communicating user requirements to programming and support staff.

Patience Continually refining user requirements by requesting -feedback; tolerating lack of computer literacy and specificity.

Assertiveness Insisting on a course of action or what one believes in, eventhough it may be unpopular.

Leadership Getting work done while keeping the team satisfied, effectivelygiving rewards and punishment.

Programming Converting system specifications into effective and efficient

computer code.Speaking Presenting your ideas in a manner easily understood by your

audience, both in group meetings and person to person.




Systems Analyst skills - Behaviour al

&Technical

Writing reparing ritten documents that accurately communicateeas n a manner a s eas y un ers oo y n en e rea ers.

istening aying attention to and concentrating on hat is being said, andasking questions that re ine points about hich one isuncertain.

Empathy eing able to understand ho others eel; accuratelydetermining hat someone else thinks about an issue.

ales romoting the system you advocate; persuading others to

accept your vie point.olitics Understanding hat motivates individuals; determining sources

o po er and in luence in an organisation.

Management lanning, organising and controlling projects so that they getdone on schedule and ithin budget.

Training Educating users and other non-technical groups on thecapabilities o computers and systems.

ooperation Working ith others productively; resolving con lict in ane ective manner.




The steering committee is formulated in

the organization to oversee the Systems

study

Usually comprises of cross functional,

senior managers within a business drawn

from the following units of an organization:

The Steering Committee




1. Personnel from IT Department

2. Vice presidents / Directors

3. Accounts Department4. Administration

Steering Committee (cont)




Steering Committee (cont)

5. Data processing Department

6. SA team (if it¶s from outside)

7. Senior Information Systems Manager




1. Main role of this group is to

conduct high-level reviews and

evaluations of proposed ISdevelopment projects and make

recommendations for prioritization

and resources for the projects.

Functions of the steering Committee




2. Study, determine and maintain an IT

policy for the organization.

3. Get views and requirements of the user

department to be represented as they try

to look for solutions for the entire

organization.

Functions of the steering Committee.(cont)




Functions of the steeringCommittee.(cont)

4. Initiating IT systems development

projects.

5. Interviewing and appointment of IT

personnel.

6. Selecting suppliers and negotiating supply

contracts with them and include penalty

clauses.




Vendors

Are those businesses which support the IS

development effort, such as consultants,

hardware, software companies, training

companies, telecommunicationcompanies, documentation companies, etc




Origin of IS Pro jects

Problem,

An opportunities,

Directives




Origin of IS Pro jects contd

1. Problems ± may either be current,

suspected, or anticipated. Problems are

undesirable situations that prevent the

business from fully achieving its purpose,goals, and objectives.





2. An Opportunity ± is a chance to

improve the business even in the

absence of specific problems.

So the business hopes to

increasing its revenue, profit, or

services, or decreasing its costs





3. A Directive ± A new requirement imposed by

the management, Government, or some

external influence




References

Systems Analysis and Design by Don Yeats, Maura

Shields and David Helmy ISBN 0-273-60066-4

Systems Analysis and Design by Kendall EK and

Kendal JE ISBN 0-13-654229-8

An introduction to Systems Analysis Techniques by Mark

Lejk and David Deeks; ISBN 0-13-857764-1

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