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PASMP Kuliah 7 Analisis Sistem-20191111091456

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Chapter 20
Introduction to Systems Development and Systems Analysis
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-1
Learning Objectives
 Explain the five phases of the systems development life
cycle.
 Discuss the people involved in systems development and
the roles they play.
 Explain the importance of systems development planning
and describe planning techniques.
 Discuss the various types of feasibility analysis and calculate
economic feasibility.
 Explain why system changes trigger behavioral reactions,
What form this resistance to change takes, and how to avoid or
minimize the resulting problems.
 Discuss the key issues and steps in systems analysis.
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-2
Why Update Systems?
 User or business changes
 Technology changes
 To improve business process
 Create competitive advantage
 Increase productivity gains
 Integrate multiple systems
 Aging systems need replacement
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-3
Software Development Problems
 Most software development projects deliver less, cost
more, and take longer than expected.
 Standish Group found that:
 70 percent of software development projects were late
 54 percent were over budget
 66 percent were unsuccessful
 30 percent were canceled before completion
 American Management Systems found that:
 75 percent of all large systems are not used
 Not used as intended, or
 Generate meaningless reports or inaccurate data
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-4
Systems Development Life Cycle
(SDLC)
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-5
SDLC Steps
 System Analysis
 Information about system needs, costs, and so on are gathered.
 Conceptual Design
 Conceptual solutions to user needs are proposed and selected.
 Physical Design
 Concepts are translated into detailed specifications.
 Implementation and Conversion




New hardware and software are installed and tested.
Employees are hired and trained or existing employees relocated.
Processing procedures are tested and modified.
Standards and controls for the new system are established and
system documentation completed.
 Operation and Maintenance
 New system is periodically reviewed.
 Modifications are made as problems arise or as new needs become
evident.
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20-6
People Interacting in SDLC
 Management
 Supports and allocate funds for projects
 Selects staff for IS department and projects.
 Accountants
 As users, project team, steering committee.
 Users
 Information systems steering committee
 Plans and oversees IS function
 Project development team
 Plan, monitor and execute particular project.
 Systems analysts and programmers
 External players
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-7
Planning SDLC
 Project Development Plan
 Cost/benefit analysis
 Developmental and operational requirements (people,
hardware, software, and financial)
 Schedule of the activities required to develop and operate
the new application
 Master Plan
 What the system will consist of
 How it will be developed
 Who will develop it
 How needed resources will be acquired
 Where the AIS is headed
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-8
Planning Technique—PERT Chart
 Program Evaluation and Review Technique (PERT)
 Network of arrows and nodes representing project activities
that require an expenditure of time and resources and the
completion and initiation of activities
 Completion time estimates made
 Critical path—the path requiring the greatest amount of
time is determined
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-9
Planning Technique—GANTT Chart
 A bar chart with project activities on the left-hand side
and units of time across the top
 Graphically shows the entire schedule for a large,
complex project
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-10
Feasibility Analysis
 Does it make sense to proceed with new system?
 Economic:
 Will system benefits justify the time, money, and resources required to
implement it?
 Technical:
 Can the system be developed and implemented using existing
technology?
 Legal:
 Does the system comply with all applicable federal and state laws,
administrative agency regulations, and contractual obligations?
 Scheduling
 Can the system be developed and implemented in the time allotted?
 Operational
 Does the organization have access to people who can design,
implement, and operate the proposed system? Will people use the
system?
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-11
Capital Budgeting: Economic
Feasibility
Cost-Benefit Analysis
Techniques
 Benefits and costs are estimated  Payback Period
 Number of years required for
and compared to determine
the net savings to equal the
whether the system is cost
initial cost of the investment.
beneficial.
 Net Present Value (NPV)
 Benefits and costs that are not
 Future benefits are discounted
easily quantifiable are estimated
back to the present.
and included.
 Initial cost is subtracted.
 Positive NPV = economically
 If they cannot be accurately
feasible.
estimated, they are listed, and
 Internal Rate of Return (IRR)
their likelihood and expected
 The effective interest rate that
impact on the organization
results in an NPV of zero.
evaluated.
 A project’s IRR is compared with
a minimum acceptable rate to
determine acceptance or 20-12
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
rejection.
System Failure Due to Change
 The best system will fail without the support of the people
it serves.
 Why people resist change:
 Fear
 Lack of top management support
 Bad experience
 Lack of communication
 Disruptive nature of change
 Methods of instituting change
 Biases and emotions
 Personal characteristics and background
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-13
Types of Resistance
 Aggression
 Behavior that destroys, cripples, or weakens system
effectiveness, such as increased error rates, disruptions, or
deliberate sabotage
 Projection
 Blaming the new system for everything that goes wrong
 Avoidance
 Ignoring a new AIS in the hope that the problem (the
system) will eventually go away
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-14
Preventing Resistance
 Obtain management support
 Meet user needs
 Involve users
 Stress new opportunities
 Avoid being too emotional
 Provide user training
 Reexamine performance evaluation to make sure they are
aligned with new system
 Keep communication lines open
 Test the system
 Keep the system simple, and humanize it
 Control users expectations
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
20-15
Systems Analysis Activities
Initial
Investigatio
n
• What’s the
Problem
• What’s the
Scope
• Preliminary
assessment of
feasibility
• Proposal to
Conduct
Systems
Analysis
Systems
Survey
Feasibility
Study
• Gain
Understanding
of Company
• Preliminary
Assessment of
Needs &
Changes
Required
• Develop
Working
Relationships
• Collect Data
• Survey Report
• Determine
Project
Viability
Copyright © 2012 Pearson Education, Inc. publishing as Prentice Hall
Information
needs and
System
Requiremen
ts
• What do Users
Need
• Document
System
Requirements
Systems
Analysis
Report
• Summarize
and
Document
Activities
20-16
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