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Lecturer: Mr. Michael Allotey Contact Information: - - PowerPoint PPT Presentation

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Lecturer: Mr. Michael Allotey Contact Information: mallotey@ug.edu.gh School of Information and Communication Studies Department of Information Studies Second Semester (2017-2018) Lecture Overview In Ghana, there are still quiet a number of

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School of Information and Communication Studies Department of Information Studies

Second Semester (2017-2018)

Lecturer: Mr. Michael Allotey Contact Information: mallotey@ug.edu.gh

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Lecture Overview

In Ghana, there are still quiet a number of organizations with manual Information systems that needs replacement to computerized ones. On the other hand, those with existing computerized systems are more likely to face one of the following possible scenarios.

  • 1. The systems might be out of date and needed replacing.
  • 2. The system in place is very limited and could be improved upon to

allow many more aspects (upgrade). All these scenarios can be addressed via the systems development lifecycle.

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Session Outline

The key topics to be covered in the session are as follows:

  • 1. Introduction
  • 2. Approaches to Information Systems Development
  • 3. Systems Development Life Cycle
  • 4. System Planning
  • 5. System Analysis
  • 6. System Design
  • 7. System Implementation
  • 8. Documentation
  • 9. Evaluation and Monitoring

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Reading List

  • Laudon, C.K. Laudon, J.P. (2000) Management Information Systems (11th Ed.), NJ, Prentice-Hall in

Honkong, Pearson.

  • Senn, J.A. (1982) Information Systems in Management, NY Wadsworth Publishing Company.
  • Stoner, J.A.F. (1999) Management, (1999) Prentice-Hall of India, New Delhi.
  • Lucey Terry, (1995) Management Information Systems, DP Publishing Ltd. Aldine Place, London.
  • Watson, H.J. et al (1991) Information System for Management: A Book of Reading.
  • Hutchinson, S.E. & Sawyer, S.C. (2000) Computers, Communications and Information: A User’s

Introduction.

  • Alter, S. (1999). Information systems: A management perspective. Reading, Mass. [u.a.: Addison

Wesley.

  • O’Brien, J.A. (2009) Introduction to Information Systems, Boston, Pearson.
  • Long, P. et al (2016) Cambridge International AS and A Level IT Coursebook, University Printing

House, Cambridge CB2 8BS, UK.

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INTRODUCTION

Topic One

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Introduction

All organizations operate in dynamic environment:

  • Competitors
  • New Technologies
  • Changing Government Regulations
  • Changing Organizational Structure

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Introduction

Organizations themselves are constantly changing in their organizational structures, resulting in:

  • Changing goals
  • Changing functional/activities
  • Changing information requirements

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APPROACHES TO INFORMATION SYSTEMS DEVELOPMENT

Topic Two

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Characteristics (Examples) of Organizational Decisions

Two approaches:

  • Evolutionary Approach
  • Systematic Approach

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SYSTEMS DEVELOPMENT LIFE CYCLE

Topic Three

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Systems Development Life Cycle

Planning Analysis Design Implementation Documentation Maintenance & Evaluation

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SYSTEM PLANNING

Topic Four

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System Planning

  • Problem definition
  • Project Identification
  • Development of Policy Framework
  • Strategizing
  • In-house Development
  • Outsourcing of Project

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SYSTEM ANALYSIS

Topic Five

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System Analysis

  • Analysis involves finding out how the current

system works and what the requirements of the clients are for the new system.

  • Involves several activities undertaken within the

framework of:

– Organizational goals – Functions – Mission/Vision

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Activities During the Analysis Stage

  • Feasibility Studies

– Human Resource – Economic – Financial – Technical

  • Strengths and

Weaknesses

  • System Requirement
  • Data Modelling
  • Process Modelling

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Basic Steps in the Analysis Stage

  • 1. Research or collect data

from the current system

  • 2. Describe the current

system (establish the inputs, outputs and processes being done).

  • 3. Identify the problems

with the current system

  • 4. Agree the objectives

with clients.

  • 5. Identify and agree

customer requirements.

  • 6. Interpret customer

requirements.

  • 7. Produce a cost-benefit

analysis.

  • 8. Identify suitable hardware

and software

  • 9. Produce a data flow

diagram.

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Methods Used to Research Current System and Requirements of the New System.

  • 1. Collecting

Information

–Questionnaires –Interviews –Observation –Document Analysis

  • 2. The Content

Specification

–Requirement Specification –System Specification –Design Specification

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Discussion Activity

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Explain why interviews are better than questionnaires for smaller group of users.

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SYSTEM DESIGN

Topic Six

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System Design

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At this Stage, diagrams are used to describe how the current system works (during the analysis phase) or they are used to demonstrate how a new system will work (during design).

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Activities at the Design Stage

The activities at the design stage are as follows:

  • Design data flow Diagrams
  • Design system flow charts
  • Design data collection forms
  • Design reports layouts and screen display
  • Design the required data/file structures and processing
  • Design validation routines
  • Specify the required hardware and software

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Discussion Activity

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An application that is to be designed will require Microsoft Access 2016 for Windows. List the minimum hardware specification that is needed to run this software

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SYSTEM IMPLEMENTATION

Topic Seven

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System Implementation

Activities:

  • Software Programming and Testing
  • Preparing Mindset of Organization
  • System Conversion
  • System Documentation
  • User Training
  • System Support

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System Implementation

System implementation can be categorized into two:

  • Testing
  • Installation (implementation)

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Testing the System

Each time a system is developed, it needs to be

  • tested. In order to test the system, test data

(normal data, extreme data and abnormal data) has to be created for the purpose of testing. Test Strategies:

  • Alpha testing and Beta testing
  • Black box testing and White box testing

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Alpha Testing and Beta Testing

  • Alpha Testing: this is carried out by the developers or a

specialized team of testers before the system is delivered to the user. (testing is planned and structured using test data)

  • Beta Testing: this is used when software is being made

available to a large number of customers. Beta testers will be real customers who have been selected to test an early release of the application. Takes place only after alpha testing. (testing involves customers using software in a real world environment using real data)

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Black Box Testing and White Box Testing

  • Black Box Testing: Involves selecting input data and checking

that the expected output data matches the actual output data (with the tester having no knowledge or understanding of the internal structure and logic of the program) Normally used to test the whole system.

  • White Box Testing: Similar to black box testing but the

internal structure and logic of the program is known to the tester. Testing in this case is focused on specific designs such as validation rules etc.

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Installation (Implementation)

There are four different methods of implementing or installing a new system which can be remembered as the 4Ps.

  • Parallel running
  • Plunge (Direct) changeover
  • Phased Implementation
  • Pilot running

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Parallel Running

  • This is running the new system while the old system is

still running.

  • This means that the result from the new system can be

checked against those of the existing system.

  • When the new system is consistently working well, the

existing system can then be stopped and replaced by the new system.

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Plunge (Direct) Changeover

  • In direct changeover, the existing system is replaced

by the new one instantly.

  • The existing system is stopped and the new system

starts running immediately.

  • This method can only be used when the new system

has been thoroughly tested.

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Phased Implementation

  • This involves the introduction of the new system one

part at a time.

  • Any problem with the new system can be overcome

and when the system is working perfectly, another aspect can be implemented.

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Pilot Running

  • This method is normally adopted by large
  • rganizations.
  • The new system is implemented in one branch of the
  • rganization whilst the other branches continue with

their existing system.

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Discussion Activity

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Describe situations when one changeover method would be more appropriate than the other.

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DOCUMENTATION

Topic Eight

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Documentation

When a system is ready to be implemented, documentation has to be produced for the new system. This documentation will take one of the two forms.

  • Technical documentation
  • User documentation

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EVALUATION & MAINTENANCE

Topic Seven

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Evaluation and Maintenance

System Evaluation After a system has been developed, tested and implemented, it must be evaluated. A system is usually evaluated against a set of criteria:

  • Is the system reliable and robust?
  • Does the system do what it is intended to do?
  • Is the system easy to use?
  • Is the new system efficient?
  • Is the solution appropriate?

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Evaluation and Maintenance Stages in the System Evaluation Process

  • 1. Using test results to evaluate the

system

  • 2. Obtaining feedback from users
  • 3. Identifying limitations of the system

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Evaluation and Maintenance

Maintenance

  • Maintenance takes place after a system has been

delivered to a customer and it is being used. There are four types or reasons for systems maintenance:

  • Perfective maintenance
  • Adaptive maintenance
  • Preventive maintenance
  • Corrective maintenance

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Perfective Maintenance

  • The idea is to be always looking to

improve the system.

  • There may not be anything wrong with

the system, but there may be ideas to make the system perform better to do additional tasks. For example: System upgrades

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Adaptive Maintenance

  • Systems need to adapt to changes.
  • It is necessary to adapt to changes so that

the system continues to work effectively and doesn’t produce incorrect results. For example: Adapting to a new technology such as new operating systems and web browsers.

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Preventive Maintenance

  • This is required to prevent problems arising within a

system.

  • This is where performance of the system is monitored to

ensure that the processor, memory, storage and other components of the system are all working efficiently. For example: Hardware equipment's regularly cleaned and regular system scans, data integrity regularly checked.

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Corrective Maintenance

  • This is done when errors and bugs are found within

the system. For example: Bugs that cause problems by making the system slow is removed using an antivirus.

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Discussion Activity

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Give a situation when corrective maintenance would be required.

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**END**

Thank You

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