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INFORMATION SYSTEM INFORMATION SYSTEM DEVELOPMENTDEVELOPMENT

INTRODUCTION TO SYSTEM INTRODUCTION TO SYSTEM ANALYSIS AND DESIGNANALYSIS AND DESIGN

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System Development EnvironmentSystem Development Environment

Most of the people in the organization Most of the people in the organization involved in information technologyinvolved in information technology

If a organization produce a system and If a organization produce a system and user make use of it then more afford user make use of it then more afford should be put into it to make it successful should be put into it to make it successful

To develop a new system, planning is a To develop a new system, planning is a important aspect to avoid failure. The important aspect to avoid failure. The planning must be widespread planning must be widespread

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System Development EnvironmentSystem Development Environment

SystemSystem is a collection of related component that is a collection of related component that interact to perform a task in order to accomplish interact to perform a task in order to accomplish a goala goal

SystemSystem is a collection of men, machine and is a collection of men, machine and methods organized to accomplish a set of methods organized to accomplish a set of specific functionspecific function

There are many types of system that can be There are many types of system that can be used to organize an organization such as used to organize an organization such as manual working system, computerized systems, manual working system, computerized systems, systems analysis and design and system systems analysis and design and system analysts analysts

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System Development EnvironmentSystem Development Environment

System analysis and designSystem analysis and design is a is a procedure to solve problem which is procedure to solve problem which is consist of 6 phases to examine and fix the consist of 6 phases to examine and fix the information system information system

Information systemInformation system is a group of hardware, is a group of hardware, software, people, procedure and datasoftware, people, procedure and data

These two elements joint together to These two elements joint together to produce basic information to organize an produce basic information to organize an organization organization

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Personnel's in system developmentPersonnel's in system development

A committee should be formed to develop A committee should be formed to develop the system. The participant in the project the system. The participant in the project are of three typesare of three types

i) User : the system under discussion should i) User : the system under discussion should always be developed in consultation always be developed in consultation with userwith user

ii) Management : such as information system ii) Management : such as information system managers who will make tactical managers who will make tactical decision about unstructured, decision about unstructured, unexpected and nonrecurring problems unexpected and nonrecurring problems

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management task : planning , management task : planning , organizing, staffing, supervising organizing, staffing, supervising and controlling the organization’s and controlling the organization’s progress progress

iii) Technical staff : members of company’s iii) Technical staff : members of company’s information system department, information system department, consisting of system analysts and consisting of system analysts and programmers and they are programmers and they are responsible to carry out and responsible to carry out and execute the projectexecute the project

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Types of information systemTypes of information system

1.1. Expert system (ES)Expert system (ES) A set of interactive computer programs that A set of interactive computer programs that

helps users solve problem that would helps users solve problem that would otherwise require the assistance of a human otherwise require the assistance of a human expertexpert

Used by both management and non Used by both management and non management personnel to solve specific management personnel to solve specific problem such as how to reduce production problem such as how to reduce production cost, improve workers’ productivity or reduce cost, improve workers’ productivity or reduce environmental impactenvironmental impact

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Created on the basic of knowledge collected Created on the basic of knowledge collected on specific topics from human experts and on specific topics from human experts and they imitate the reasoning process of human they imitate the reasoning process of human being being

Run in large computers – require large Run in large computers – require large memory. E.g. Negotiator Pro for IBM and memory. E.g. Negotiator Pro for IBM and Macintosh computerMacintosh computer

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2.2. Transaction processing system (TPS)Transaction processing system (TPS) computer-based information that keeps track of computer-based information that keeps track of

the transactions needs to conduct business the transactions needs to conduct business Transaction is a recoded event having to do with Transaction is a recoded event having to do with

routine business activitiesroutine business activities Some featuresSome features

Input to the system are transaction data : bills, Input to the system are transaction data : bills, orders, inventory levels. Output consists of orders, inventory levels. Output consists of processed transactions bills, paychecksprocessed transactions bills, paychecks

For lower managers – TPS deals with day-to-For lower managers – TPS deals with day-to-day matters, helps to make operational day matters, helps to make operational decisionsdecisions

Produces details reports –Produces details reports – manager receive the manager receive the reportreport

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3.3. Management Information System (MIS)Management Information System (MIS) Computer based information system that Computer based information system that

uses data recorded by TPS as input into uses data recorded by TPS as input into programs that produce routine reports as programs that produce routine reports as outputoutput

Some featuresSome features Input : processed transaction data such as bills, Input : processed transaction data such as bills,

orders and paychecksorders and paychecks

output : summarized, structured reports – budget output : summarized, structured reports – budget summaries, production schedules summaries, production schedules

Assist middle managersAssist middle managers Draw from all departmentsDraw from all departments Produces several kinds reportsProduces several kinds reports

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4. Decision Support System (DSS)4. Decision Support System (DSS) computer based information system that computer based information system that

provides a flexible tool for analysis and helps provides a flexible tool for analysis and helps managers focus on the futures managers focus on the futures

The organization must have established a The organization must have established a transaction processing system and a transaction processing system and a management information systemmanagement information system

Some featuresSome features input : some processed transaction datainput : some processed transaction data

Output : are flexible – on demand reportsOutput : are flexible – on demand reportsTo assist top managersTo assist top managersProduces analytic modelsProduces analytic models

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Analytic ModelsAnalytic Models

The models uses a DSS databaseThe models uses a DSS database The system is accessed through DSS The system is accessed through DSS

softwaresoftware The model allows the managers to do a The model allows the managers to do a

simulation simulation

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Information System DevelopmentInformation System Development

System development methodologiesSystem development methodologiesa)a) Waterfall modelsWaterfall models

From the big idea of the system, then it is braked From the big idea of the system, then it is braked into small problem/task. Each task will be solved into small problem/task. Each task will be solved and finally the system will be developed and finally the system will be developed

b)b) Rapid application development modelsRapid application development models FasterFaster Uses the most simple way to produce the resultUses the most simple way to produce the result E.g. calculator (electronic calculation machine)E.g. calculator (electronic calculation machine)

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Information System DevelopmentInformation System Development

c)c) Evolution modelsEvolution models SlowSlow Needs to pass through a few Needs to pass through a few

steps/processes to get a resultsteps/processes to get a result E.g. students’ co-curriculum marks E.g. students’ co-curriculum marks

system – developed using more than one system – developed using more than one softwaresoftware

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System Development Life CycleSystem Development Life CyclePreliminary Investigation

System Maintenance

System Development

SystemDesign

SystemAnalysis

System Implementation

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Main phases in system Main phases in system developmentdevelopment

Preliminary InvestigationPreliminary Investigation

Conduct preliminary analysis

Purpose alternative solution

Describe cost & benefits of each solution

Submit a preliminary plan with recommendations

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System AnalysisSystem Analysis

Gather data

Analyze the data

Make a written report

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System DesignSystem Design

Make a preliminarydesign and then a

detail design

Write a report

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System DevelopmentSystem Development

Acquire the hardware and software

andtest the system

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System Implementation System Implementation

Convert the hardware, softwareand files to the new system

Train the users

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System MaintenanceSystem Maintenance

Audit the system

Evaluate it periodically