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MIS 601 : ManagementInformation Systems
Topic VII : Developing
Business/IT Solutions
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Contents
IS Development SystemsApproach
Systems DevelopmentLifecycle
Systems InvestigationSystems Analysis
Systems Design
Systems Implementation
Systems Maintenance
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Information Systems Development
When the systems approach to problemsolving is applied to the development of
IS solutions to Business problems it iscalled Information SystemsDevelopment.
The key to successful SystemsDevelopment is through Systems
Analysis & Design (SSAD)
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Information Systems Development
Systems Analysis
The process of understanding and specifying indetail what the information system should do?
Systems Design
The process of specifying in detail how manycomponent parts of the information systemshould be physically implemented.
Systems AnalystThe person who uses Analysis and Designtechniques to solve business problems using IT.
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Systems Approach to Problem Solving
Design
theSolution
Design
theSolution
UnderstandThe Problem
UnderstandThe Problem
DevelopAlternativeSolutions
DevelopAlternativeSolutions
Select
theSolution
Select
theSolution
Implementthe
Solution
Implementthe
Solution
MonitorandEvaluate
Results
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Systems Analyst
Using Systems Engineering to understanda problem or opportunity is one of the
most important task of a SystemsAnalyst:-What should it do?
What are the component parts?
How should they be configured?
What technology should be used to build the different components?
Who should build them?
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Systems Development Life Cycle
(SDLC)Using the systems approach to develop
Information System Solutions can beviewed as a multi step process called asa Systems Development Life Cycle
(SDLC)
Depending upon the products that result
from each step in the cycle, you canrecycle back to any previous step if morework is needed.
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Systems Development Life Cycle (SDLC)
There are 5 stages in this cycle :-Investigation
AnalysisDesign
ImplementationMaintenance
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Traditional Systems Development Life Cycle
Systems Implementation
Product:Operational System
Systems Implementation
Product:Operational System
Systems InvestigationProduct:
Feasibil ity Study
Systems InvestigationProduct:
Feasibili ty Study
Systems Analysis
Product:Functional Requirements
Systems Analysis
Product:Functional Requirements
Systems Design
Product:System Specif ications
Systems Design
Product:System Specifications
Systems Maintenance
Product:Improved System
Systems Maintenance
Product:Improved System
Understand theBusinessProblem orOpportunity
Develop anInformation
SystemSolution
Implementthe InformationSystemSolution
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Phase 1 : Systems Investigation
What are the Business Priorities?How can Information Technologiesprovide Information systemsSolutions that address theBusiness Proprieties?
The above questions like above,have to be answered in theSystems Investigation Stage.
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Phase 1 : Systems Investigation
Feasibility Study:A feasibility study is a preliminary studywhere the information needs ofprospective users and the resourcerequirements, costs, benefits & feasibilityof a proposed project are determined.The goal of feasibility study is to evaluate alternativesystem solution and to propose the most feasible anddesirable business application for development.
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Systems Investigation
Organizational
Feasibility
Is it a good fit?
OperationalFeasibility
Will i t be accepted?
Economic
Feasibility
Can we afford it?
TechnicalFeasibility
Does the
capabil ity exist?
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Feasibility Study
Organizational Feasibility:-Q) How well a proposed Information
system fits the companys Sales,Marketing and Financial Plans?
Technical Feasibility:-Q) Whether we have technical resources
to build the new system?
Q) Whether we have to purchase newtechnology?
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Feasibility Study
Economic Feasibility:-Savings in Labour Costs?
Increased Sales Revenue?
Decreased Investment in Inventory?
Increased Profits?
Operational Feasibility:-
Acceptance by employees?Management Support?
Customer and supplier acceptance?
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Cost/ Benefit Analysis
Feasibility Studies typicallyinvolve Cost/ Benefit Analysis. If
costs and benefits can bequantified, they are called
tangible, if not they are calledas intangible.
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Cost/ Benefit Analysis
Cost/ BenefitAnalysis
Costs Benefits
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Cost/Benefit AnalysisCosts
Tangible Costs IntangibleCosts
Fixed
Costs
Recurring
Costs
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Cost/ Benefit Analysis
Benefits
Tangible
Benefits
Intangible
Benefits
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Tangible Benefits
Increase in Sales/ProfitsDecrease in Information
Processing costsDecrease in Operating Costs
Decrease in Required InvestmentsIncreased Operational Efficiency
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Intangible Benefits
Improved Decision MakingImproved abilities in analysis
Improved Customer serviceImproved Employee Morale
Improved Competitive PositionImproved Business Image
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Phase 2 : Systems Analysis
Systems Analysis is an indepth study of end userinformation needs, thatproduces functional
requirements that areused as the basis for thedesign of a newInformation system.
.
Systems
Requirements
Functional
Requirements
Technical
Requirements
i
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Systems Requirements
Stakeholders
User
Stakeholders
Client
Stakeholders
Technical
Stakeholders
U S k h ld
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User Stakeholders
User
Stakeholders
Business
OperationUsers
ManagementUsers
F tFi di
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Fact Finding
The objective of the analysis phase of
systems development is to understandthe business functions & develop thesystem requirements.
Q. What are the Business Processes and operations?
Q. How should the Business Processes be performed?
Q. What are the informationrequirements?
FactFindingTechniques
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Fact Finding Techniques
Fact
Finding
Techniques
QuestionnairesReview
DocumentsInterviewing
ObserveBusiness
Processes
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Questionnaires
Large number of audience.Discretion
Very good for Preliminary investigationTypes of Questions:-
Closed Ended QuestionsObjective Type Questions
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Review Documents
Good way to get a preliminaryunderstanding.
These documents serve as Visual aidsduring the interview itself.
It is better to have filled forms ratherthan blank forms.
Interview
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InterviewBefore
Objective
Correct Users
Project Team membersList of questions
During
Inform exact objectivesProbe for details
Look for exceptions
AfterReview Notes for accuracy
Transfer information into proper documents
Identify areas for further clarifications
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Observe Business Processes
There is no better way to learn howusers actually use a system and whatinformation they need than to observefirst hand work being done.
A Quick Walkthrough
Users nervous
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Systems Design
DataDesignData
Design
UserInterfaceDesign
UserInterfaceDesign
ProcessDesign
ProcessDesign
Screen, Form, Report
and Dialog Design
Data Element
Structure DesignProgram and
Procedure Design
Systems Design consists of design activities thatproduce systems specifications satisfying thefunctional requirements that were developed in the
systems analysis process
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User Interface Design
Key Guidelines:Aesthetics
Easy to NavigateSearchibility
End User development
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Data Design
Key Guidelines:Entities
AttributesRelationships
KeysReferential Integrity
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Process Design
Key Guidelines:Decision Structures
Choice of LoopsSubroutines
Call By Reference
Call By Value
Use of Global Variables
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Phase IV : ImplementingBusiness Systems
Systems Implementation stage involves hardwareand software acquisition, software development,testing of programs and procedures, development ofdocumentation and variety of conversion alternatives.
Implementation activities are required to transform anewly developed Information system into anoperational system for end users.
TheImplementationProcess
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The Implementation Process
ConversionConversionSystemDocumentation
SystemDocumentation
End UserTraining
End UserTraining
Developmentand
Modification
Developmentand
ModificationAcquisitionAcquisition
ImplementationActivities
ImplementationActivities
SystemTesting
SystemTesting
EvaluatingHardware software &services
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Evaluating Hardware, software & services
Suppliers place Bids and proposals
Minimum acceptable physical &performance characteristics areestablished
Requirements are finalised byfollowing documents:-
RFP
RFQ
Scoring System for evaluating
proposals.
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TestingSystem Testing may involve :-
Testing website performance
Testing & Debugging software
Testing should not only occur only during thesystems implementation stage, but
throughout systems development process.
Documentation
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Documentation
Internal
Documentation
External
Documentation
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Training
Its a vital implementation activityTraining must involve activities such asData Entry.
Training must also involve all aspects ofproper use of a new system.
IS personnel such as USER CONSULTANTmust be sure that end users are trained tooperate the new e business system, else
the implementation will fail.
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Conversion methods
The initial operation of a new businesssystem can be a difficult task. Ittypically involves conversion process
from the use of a present system to theoperation of a new or improvedapplication.
Conversion methods can soften theimpact of introducing new Information
Technologies into an organisation.
Installation Conversion Methods
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Installation Conversion Methods
Old SystemOld System New SystemNew System
Old SystemOld System
New SystemNew System
Old SystemOld System
Old SystemOld System New System
New System
Parallel
Pilot
Phased
Plunge
Conversionmethods
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Conversion methods
Parallel
Conversions can be done on a parallel, wherebyboth old and new systems are operating untilthe project development team & endusersagree for a complete switchover
PlungeInstallation is accomplished by a direct cutoveror plunge into the newly developed system.
Conversionmethods
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Conversion methods
Phased Basis
Conversions can be done in a phased basis,where only parts of a new application (fewdepartments, branch offices) at a time areconverted.
Pilot Conversion
Here one department serves as a Test Site. A
new system can be tried out at this site untildevelopers feel it can be implementedthroughout the organization.
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PHASE V : IS Maintenance
Systems Maintenanceis the monitoring,evaluating and modifying of operational businesssystems to make desirable or necessaryimprovements.
Maintenance is also necessary for other failures &problems that arise during the operation of asystems. End users and IS personnel then
perform a Trouble shooting function todetermine the causes of and solutions to suchproblems.
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IS Maintenance
Maintenance also includes makingmodifications to an established systemdue to changes in BusinessOrganizations or Business Environment.
EgEg : New Tax Legislation: New Tax Legislation
New eNew e business initiativesbusiness initiatives