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LAST WEEK LESSON
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SUMMARY
Weve learned about the basic business activities
in which an organization engages, the decisions
that need to be made, and the information required
to make those decisions.
Weve reviewed the data processing cycle and its
role in organizing business activities and
providing information to users.
Finally, weve touched on the role of theinformation systems in modern organizations and
introduced the notion of enterprise resource
planningsystems.
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Basic Business Activities
Expenditure
Cycle
Human
Resources
ProductionCycle
RevenueCycle
Financing
Cycle
General Ledger & Reporting System
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ERP Systems
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C HAPTER 20 DAN 22
Systems Development
Process
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Learning Objectives
1. Explain the five phases of the systems developmentlife cycle.
2. Discuss the peopleinvolved in systems development
and the roles they play.3. Explain the importanceof systems development
planning and describe planning techniques.
4. Explain why system changes trigger behavioralreactions,
What form this resistance to change takes, and how to avoid or minimize the resulting problems.
5. Discuss the key issues and steps in system analysis.
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INTRODUCTION
As the environment, technology, and
competition change, an information
system must continually undergo changes
These changes range from minor
adjustments to major overhauls.
Occasionally the old system is scrapped
and replaced.
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INTRODUCTION
Companies change their systems for a variety ofreasons: To respond to changes in user needs or business needs
To take advantage of or respond to technology changes
To accommodate improvements in their businessprocess
To gain a competitive advantage and/or lower costs
To increase productivity
To accommodate growth To accommodate downsizing or distribute decision
making
To replace a system that is aged and unstable
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Learning Objective 1
Explain the five phases of the systemsdevelopment life cycle.
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SYSTEMS DEVELOPMENT LIFE CYCLE
The five stages (Mulyadi: three steps) inthe systems development life cycle are:
System Analysis
Conceptual Design Physical Design
Implementation and Conversion
Operation and Maintenance
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Systems Development Life Cycle (SDLC)
SystemAnalysis
ConceptualDesign
Physical DesignImplementation& Conversion
Operations &Maintenance
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Learning Objective 2
Discuss the people involved in systemsdevelopment and the roles they play.
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THE PLAYERS
Many people are involved in developing andsuccessfully implementing an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
Many people are involved in developing andsuccessfully implement an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
Top managements role in systemsdevelopment is to: Provide support and encouragement and a clear
signal that user involvement is important.
Help align the systems with corporate strategies.
Establish system goals and objectives.
Review IS department performance and leadership.
Establish policies for project selection and
organizational structure. Participate in important systems decisions.
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THE PLAYERS
User management needs to: Determine information requirements for departmental
projects.
Assist systems analysts with project cost-benefit
estimates.
Assign key staff members to development projects.
Allocate funds.
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THE PLAYERS
Many people are involved in developing andsuccessfully implement an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
Accountants also play an important role insystems development: As AIS users, they must determine their information needs
and systems requirements and communicate them to
system developers. As members of project development teams or steering
committees, they help management in the developmentprocess.
They are also active in:
Designing system controls and monitoring and testing thesecontrols.
Ensuring the system is easy to audit.
Controls and auditability need to be built in early tominimize costs and inefficiencies later.
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THE PLAYERS
Many people are involved in developing andsuccessfully implement an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
The information systems steering committee isan executive-level committee whose duty is toplan and oversee the IS function. Consists of high level management, such as:
Controller
IS Manager
User department managers
Sets policies to govern the AIS and assure top-
management participation, guidance, and control. Attempts to encourage goal congruence and reduce
goal conflict.
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THE PLAYERS
Many people are involved in developing andsuccessfully implement an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
The project development team includes systemsspecialists, managers, accountants, auditors, and userswhose responsibility is to guide development
Their job:
Plan each project. Monitor to ensure timely and cost-effective completion.
Ensure the human element is considered.
Communicate project status to top management and steeringcommittee.
Communicate and meet with users to: Consider ideas
Discuss progress
Eliminate surprises
The team approach produces more effective results and betteruser acceptance.
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THE PLAYERS
Many people are involved in developing andsuccessfully implement an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
Systems analysts study existing systems,design new ones, and preparespecifications that are used by
programmers. They interact with technical personnel and
users to bridge the gap.
They are responsible for ensuring the system
meets user needs.
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THE PLAYERS
Many people are involved in developing andsuccessfully implement an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
Computer programmers write thecomputer programs, using the specsdeveloped by the systems analysts.
They also modify and maintaining existingprograms.
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THE PLAYERS
Many people are involved in developing andsuccessfully implement an AIS, including:
Top management
Accountants The information systems steering committee
The project development team
Systems analysts
Computer programmers External players
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THE PLAYERS
External players include:
Customers
Vendors
Auditors Governmental entities
Their needs must also be met in systems
development.
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Learning Objective 3
Explain the importance of systemsdevelopment planning and describe
planning techniques.
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PLANNING SYSTEMS DEVELOPMENT
Several activities must be performed at varioustimes throughout the SDLC.
One of these activities is planning.
The organization should have plans for: The long range
Each systems development project
Each phase of each systems development project
Well discuss these plans and a number oftechniques to develop them.
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PLANNING SYSTEMS DEVELOPMENT
Systems development planning is an importantstep for the following key reasons: Consistencywith the organizations strategic plan.
Efficiencyachieved through coordination of thesubsystems.
Cutting edgetechnology and techniques.
Lower costsdue to lack of duplication, wasted effort,time overruns, and cost overruns.
Adaptabilityfor future changes.
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PLANNING SYSTEMS DEVELOPMENT
Two types of systems development plansare needed:
- Individual project plans developed by the
project teams.- A master plan developed by the IS steering
committee.
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PLANNING SYSTEMS DEVELOPMENT
Two types of systems development plansare needed:
- Individual project plans developed by the
project teams.- A master plan developed by the IS steering
committee.
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PLANNING SYSTEMS DEVELOPMENT
Individual project plans contain: A cost-benefit analysis.
Developmental and operational requirements,including:
Human resources
Hardware
Software
Financial resources
A schedule of activities to develop and operate thenew application
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PLANNING SYSTEMS DEVELOPMENT
Two types of systems development plansare needed:
- Individual project plans developed by the
project teams.- A master plan developed by the IS steering
committee.
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PLANNING SYSTEMS DEVELOPMENT
A master plan specifies: 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
It also provides:
Status of projects in process Prioritization of planned projects and criteria forestablishing priorities
Timetables for development
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PLANNING SYSTEMS DEVELOPMENT
Projects with highest priority are first to bedeveloped. These decisions are made by top management.
Planning horizon: About a 3-year horizon
With updates at least 2-3 times/yeareven morefrequently in some companies.
The CIO should determine: How soon technologies will be in wide use
Whether the company should adopt late or early
What business opportunities might arise from newtechnologies
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PLANNING SYSTEMS DEVELOPMENT
Planning Techniques
Two techniques for scheduling and
monitoring systems development
activities are:
Program Evaluation and Review Technique
(PERT)
Gantt Charts
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PLANNING SYSTEMS DEVELOPMENT
Planning Techniques
Two techniques for scheduling and
monitor systems development activities
are:
Program Evaluation and Review
Technique (PERT)
Gantt Charts
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PLANNING SYSTEMS DEVELOPMENT
A PERT diagram requires that all activities
in a project be identified along with the
activities that precede and follow them.
These activities are used to draw a PERT
diagram, which consists of a network of:
Arrowsrepresenting activities that require
time and resources. Nodesrepresenting completion and initiation
of activities.
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PLANNING SYSTEMS DEVELOPMENT
The critical path in a PERT diagram is the
path requiring the greatest amount of time.
If an activity on the critical path is delayed,
the whole project is delayed.
Resources may be shifted to the critical
path to reduce the delay.
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Design
Birdhouse
(2)
(Bill)
Buy Wood
& Nails
(1)(Bill)
Buy
Paint
(1)
(Sara)
Build
Base
(2)(Bill)
Build
Roof
(1)
(Bill)
Nail
Together
(2)
(Bill)
Paint &
Decorate
(3)
(Sara)
Sell
(2)
(Sara)
SAMPLE PERT CHART For building and selling a birdhouse.
Each block contains a task and a time estimate (may
include best time, worst time, and average time) May indicate who will be responsible for the task.
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PLANNING SYSTEMS DEVELOPMENT
Planning Techniques
Two techniques for scheduling and
monitor systems development activities
are:
Program Evaluation and Review Technique
(PERT)
Gantt Charts
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PLANNING SYSTEMS DEVELOPMENT
A Gantt chart is a bar chart with project activities
on the left and time across the top.
For each activity, a bar of expected time is
drawn. As activities are completed, the bar is filled in.
The Gantt chart makes it easy to eyeball the
chart and understand the current status of a
project.
But the chart does not show the relationship
between activities like the PERT chart does.
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SAMPLE GANTT CHART
1 2 3 4 5 6 7 8 9 10
Design birdhouse
Buy wood & nails
Buy paint
Build roofBuild base
Nail together
Paint & decorate
Sell
Period
Complete
Testing
In Development
Milestone
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Learning Objective 4
Explain why system changes triggerbehavioral reactions.
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BEHAVIORAL ASPECTS OF CHANGE
The best system will fail without the
support of the people it serves.
So the behavioral aspects of change are
crucial.
You need to be aware of and sensitive to
the types of behavioral problems that can
result from change.
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BEHAVIORAL ASPECTS OF CHANGE
Why Behavioral Problems Occur
Employees will tend to view change as good if
they believe it will affect them positively and
vice versa.
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BEHAVIORAL ASPECTS OF CHANGE
To minimize adverse behavioral reactions,
it helps to understand why resistance
occurs:
Personal characteristics and background Manner in which change is introduced
The rationale used to sell the system may need to vary
with the job responsibilities of the employees involved.
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BEHAVIORAL ASPECTS OF CHANGE
To minimize adverse behavioral reactions,
it helps to understand why resistance
occurs:
Personal characteristics and background Manner in which change is introduced
Experience with prior changes Fool me once, shame on me . . .
Lets see if I even give you asecond chance.
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BEHAVIORAL ASPECTS OF CHANGE
To minimize adverse behavioral reactions,
it helps to understand why resistance
occurs:
Personal characteristics and background Manner in which change is introduced
Experience with prior changes
Top management support
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BEHAVIORAL ASPECTS OF CHANGE
To minimize adverse behavioral reactions,
it helps to understand why resistance
occurs:
Personal characteristics and background Manner in which change is introduced
Experience with prior changes
Top management support
Communication
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BEHAVIORAL ASPECTS OF CHANGE
To minimize adverse behavioral reactions,
it helps to understand why resistance
occurs:
Personal characteristics and background Manner in which change is introduced
Experience with prior changes
Top management support
Communication Biases and natural resistance to change
Disruptive nature of the change process
Disturbances often create
negative feelings.
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BEHAVIORAL ASPECTS OF CHANGE
To minimize adverse behavioral reactions,it helps to understand why resistanceoccurs:
Personal characteristics and background Manner in which change is introduced Experience with prior changes Top management support Communication Biases and natural resistance to change Disruptive nature of the change process Fear
May include fear of:
The unknown
Failure
Technology
Losing respect or status
Losing their jobs
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BEHAVIORAL ASPECTS OF CHANGE
How People Resist AIS Changes
Resistance to change often takes one of
three forms:
Aggression
Behavior intended to destroy, cripple, or weaken the
systems effectiveness.
Examples: Increased error rates, disruptions, or
deliberate sabotage.
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BEHAVIORAL ASPECTS OF CHANGE
How People Resist AIS Changes
Resistance to change often takes one of
three forms:
Aggression
Projection
Blaming the new system for any and every unpleasant
occurrence, i.e., the system becomes a scapegoat. To preserve the integrity of the system, these criticisms
must be controlled or answered.
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BEHAVIORAL ASPECTS OF CHANGE
How People Resist AIS Changes
Resistance to change often takes one of
three forms:
Aggression
Projection
Avoidance
If I dont use this thing, maybe it will go away!
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BEHAVIORAL ASPECTS OF CHANGE
Reactions to change can be improved by
observing the following guidelines:
Meet users needs with respect to the form,
content, and volume of system output. Keep communication lines open. Managers
and users should be fully informed about:
What changes are being made
Why
How it will benefit them
Who to contact with questions
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BEHAVIORAL ASPECTS OF CHANGE
Maintain a safe and open atmosphere.
If employees become hostile, its an uphill battle
you probably wont win.
Obtain management support.Allay fears.
To the extent possible, reassure employees that
no major job losses or responsibility shifts will
occur. If employees are terminated, severance pay and
outplacement services should be provided.
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BEHAVIORAL ASPECTS OF CHANGEIS
Solicit user participation.
It is ego enhancing, challenging, and intrinsically
satisfying.
Users who participate will be more committed to
using the system.
Provide honest feedback.
Explain which suggestions are and are not being
used and why. Make sure users understand the system.
Dont underestimate training needs.
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BEHAVIORAL ASPECTS OF CHANGE
Humanize the system. Employees shouldnt feel the computer is
controlling them or has usurped their positions.
Describe new challenges and opportunities. The system can provide greater job satisfaction
and increased opportunities.
Reexamine performance evaluation. Are performance standards and criteria realistic in
light of the change?
Test the systems integrity. It important to minimize bad impressions
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BEHAVIORAL ASPECTS OF CHANGE
Avoid emotionalism.
Emotional issues should be allowed to cool, handled in
a non-confrontational manner, or sidestepped.
Present the system in the proper context.
Address the concerns of the people to whom youre
speaking, not the concerns of management or
developers.
Control the users expectations
Dont oversell, and be realistic.
Keep the system simple
Avoid complex systems that cause radical changes.
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BEHAVIORAL ASPECTS OF CHANGE
Ignoring the preceding steps can leave to
behavior issues that are difficult or
impossible to reverse.
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Learning Objectives
1. Discuss the system analysis process and the activitiesin this phase
2. Discuss the conceptual systems design process and
the activities in this phase.
3. Discuss the physical systems design process and theactivities in this phase.
4. Discuss the systems implementation and conversion
processand the activities in this phase.
5. Discuss the systems operation and maintenanceprocess and the activities in this phase.
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Learning Objective 1
Discuss the system analysis process and
the activities in this phase
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SYSTEMS ANALYSIS
When a new or improved system is
needed, a written request for systems
development is prepared. That request
describes: The current systems problems
The reasons for the proposed changes
The goals and objectives of a proposedsystem
The anticipated benefits and costs
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SYSTEMS ANALYSIS
The project development team will conduct
the systems analysis in five steps:
Initial investigation
Systems survey
Feasibility study
Information needs and systems requirements
Systems analysis report
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SYSTEMS ANALYSIS
The project development team will conduct
the systems analysis in five steps
Initial investigation
Systems survey
Feasibility study
Information needs and systems requirements
Systems analysis report
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SYSTEMS ANALYSIS
The initial investigation is conducted to:
Gain a clear picture of the problem or
need.
Sometimes what is thought to be the cause of theproblem is not the real source.
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SYSTEMS ANALYSIS
The initial investigation is conducted to:
Gain a clear picture of the problem or need.
Determine the viability of the project and
expected costs and payoffs.
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SYSTEMS ANALYSIS
The initial investigation is conducted to:
Gain a clear picture of the problem or need.
Determine the viability of the project and
expected costs and payoffs. Evaluate the scope and nature of the new
AIS.
A new AIS is useful when problems are a result of:
Lack of information
Inaccessibility of data
Inefficient data processing
A new AIS will not answer problems such as:
A manager who has too many subordinates
A manager who lacks organizational skills
Failure to enforce existing problems
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SYSTEMS ANALYSIS
The initial investigation is conducted to:
Gain a clear picture of the problem or need.
Determine the viability of the project and
expected costs and payoffs. Evaluate the scope and nature of the new
AIS.
Recommend whether to proceed.
Either: Initiate the project as proposed.
Modify it.
Abandon it.
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SYSTEMS ANALYSIS
If the project is approved:
A proposal to conduct systems analysis is
prepared.
The project is assigned a priority and addedto the master plan.
The development team begins a survey of the
existing AIS.
The proposal will be modified as more
information becomes available.
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SYSTEMS ANALYSIS
The project development team will conductthe systems analysis in five steps
Initial investigation
Systems survey
Feasibility study
Information needs and systems requirements
Systems analysis report
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SYSTEMS ANALYSIS
A systems survey involves an extensive study of thecurrent AIS which could take weeks or months.Objectives are: Gain a thorough understanding of:
Company operations, policies, and procedures
Data and information flow
AIS strengths and weaknesses
Available hardware, software, and personnel
Make preliminary assessments of current and future
processing needs, and determine extent and nature ofneeded changes.
Develop working relationships with users and build support.
Collect data that identify user needs, conduct a feasibilityanalysis, and make recommendations to management.
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SYSTEMS ANALYSIS
Data can be gathered from:
Employees.
Documentation such as organization charts
and procedure manuals. External sources such as:
Consultants
Customers
Suppliers
Industry associations
Government agencies
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SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Once the data is gathered, documentfindings and model the existing system.
Documentation consists of:
Questionnaire copies Interview notes
Memos
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Another form of documentation is asystem model:
Physical modelsillustrate how a systemfunctions by describing: Flow of documents.
Computer processes performed and the peopledoing them.
Equipment used.
Any other physical elements.
Logical modelsillustrate what is being doneregardless of how the flow is accomplished.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
At the end of this phase, prepare systemssurvey report:
Outlines and documents the data gathered.
Provides recommendations that result fromthe systems survey.
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SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
After the systems survey, a more thoroughfeasibility analysis is conducted.
This analysis is updated regularly as the
project proceeds and costs and benefitsbecome clearer.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
The project development team will conductthe systems analysis in five steps
Initial investigation
Systems survey
Feasibility study
Information needs and systems
requirements Systems analysis report
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
Describes what is to be doneand by whom.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
- Data elements
Describes name, size, format,
source, and significance of
necessary data elements.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
- Data elements- Data structure A preliminary structure showing
how the data elements will be
organized into logical records.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
- Data elements- Data structure
- Outputs Layouts of system outputs and a
description of their purpose,
frequency, and distribution.
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SYSTEMS ANALYSIS
Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
- Data elements- Data structure
- Outputs
- Inputs A copy of system inputs and a
description of their contents,
source, and who is responsiblefor them.
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SYSTEMS ANALYSIS
Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
- Data elements- Data structure
- Outputs
- Inputs
- Constraints
A description of deadlines,
schedules, security requirements,
staffing limitations, and legalrequirements.
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Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
- Data elements- Data structure
- Outputs
- Inputs
- Constraints
- Controls Controls that are needed to
ensure accuracy and reliability.
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Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and
documents systems processes, including:
- Processes
- Data elements- Data structure
- Outputs
- Inputs
- Documentation constraints
- Controls
- Reorganizations Changes in staffing, job
functions, etc., that would be
necessary.
SYSTEMS ANALYSIS
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Issues: There is much to be specified, even for a
simple AIS.
It may be difficult to get employees toaccurately articulate their needs.
Errors are best caught early, as the cost to
correct them increases significantly the farther
you are into the project.
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Systems Objectives and Constraints Many entities take a systems app roachto
determining information needs and systems
requirements. Problems and alternatives are viewed from
the standpoint of the entire organizationas
opposed to a single department.
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SYSTEMS ANALYSIS
Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
Able to help users make
decisions.
SYSTEMS ANALYSIS
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Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
Benefits exceed costs.
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Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
Data is processed accuratelyand reliably.
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SYSTEMS ANALYSIS
Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability You can access it when you
need it.
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Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
More critical information is
provided first.
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SYSTEMS ANALYSIS
Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
- Customer service
Efficient and courteous.
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Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
- Customer service
- Capacity
Can handle peak periods.
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Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
- Customer service
- Capacity
- Ease of use
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Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
- Customer service
- Capacity
- Ease of use
- Flexibility
Can accommodate changes.
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SYSTEMS ANALYSIS
Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
- Customer service
- Capacity
- Ease of use
- Flexibility
- Tractability Easily understood.
Facilitates problem solving and
future development.
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SYSTEMS ANALYSIS
Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
- Customer service
- Capacity
- Ease of use
- Flexibility
- Tractability- Auditability
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Systems objectives must be identified, soanalysts and users can focus on those elements
most vital to success of the AIS. These may
include:
- Usefulness
- Economy
- Reliability
- Availability- Timeliness
- Customer service
- Capacity
- Ease of use
- Flexibility
- Tractability- Auditability
- Security Available only toauthorized users.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
There are often trade-offs between objectives.
Organizational constraints make it impossible to
develop all parts of an AIS simultaneously.
You divide it into modules that are analyzed,developed, and installed independently.
When changes are made, only the affected modules
need to be changed.
The modules should be properly integrated into aworkable system.
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SYSTEMS ANALYSIS
Strategies for DeterminingRequirements:
One or more of the following four strategies
are used to determine AIS requirements: Ask users what they need
This is the simplest and fastest strategy.
But many people dont realize or understand their true
needs. Its sometimes better to ask them what decisions they
make and what processes they are involved in.
Users also need to think beyond their current
information needs.
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Strategies for DeterminingRequirements:
One or more of the following four strategies
are used to determine AIS requirements: Ask users what they need
Analyze existing systems
Internal and external systems should be analyzed to
avoid reinventing the wheel.
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Strategies for DeterminingRequirements:
One or more of the following four strategies
are used to determine AIS requirements: Ask users what they need
Analyze existing systems
Examine existing system use
Certain modules:
May not be used as intended
May be augmented by manual tasks
May be avoided altogether
Helps determine whether the system really needs to be
simply modified rather than replaced.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Strategies for DeterminingRequirements:
One or more of the following four strategies
are used to determine AIS requirements: Ask users what they need
Analyze existing systems
Examine existing system use
Create a prototype
Entails roughing out a system for users to critique. When they see something on a screen, its easier to
identify what they like and dont like.
Goes through iterations of improving and reviewing
with users until users agree on their needs.
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SYSTEMS ANALYSIS
Documentation and Approval of UserRequirements:
Detailed requirements for the new AIS shouldbe created and documented. How to produce the required features is
determined during the design phases of the SDLC.
The requirements list should be supported bysample input and output forms and charts that
make it easier to conceptualize. A nontechnical summary is often prepared for
management.
SYSTEMS ANALYSIS
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SYSTEMS ANALYSIS
Once user requirements have beendetermined and documented, the project
team:
Meets with users. Explains the requirements.
Obtains their agreement and approval.
When an agreement is reached, usermanagement should sign off on the
requirements.
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SYSTEMS ANALYSIS
The project development team will conductthe systems analysis in five steps
Initial investigation
Systems survey Feasibility study
Information needs and systems requirements
Systems analysis report
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Learning Objective 2
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g j
Discuss the conceptual design process
and the activities in this phase
CONCEPTUAL SYSTEMS DESIGN
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In the conceptual sys tems designphase, a general framework is created forimplementing user requirements andsolving the problems identified in theanalysis phase.
The three main steps are: Evaluate design alternatives.
Prepare design specifications. Prepare the conceptual systems design
report.
Systems
AnalysisConceptual
Systems
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Prepare
Design
Specifications
PhysicalDesign
Implementation
And
Conversion
Operation
And
Maintenance
Prepare
Conceptual Systems
Design report
Evaluate
Design
Alternatives
Systems
Design
Systems
Analysis
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Prepare
Design
Specifications
PhysicalDesign
Implementation
And
Conversion
Operation
And
Maintenance
Prepare
Conceptual Systems
Design report
Evaluate
Design
Alternatives
CONCEPTUAL SYSTEMS DESIGN
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Evaluating Design Alternatives There are many design decisions that must
be made. For example:
Should a document be hard-copy or sent by EDI? Should the company use a large centralized
mainframe or some form of distributed processing?
What form should data entry take, e.g., keyboard,
optical character recognition, POS devices?
CONCEPTUAL SYSTEMS DESIGN
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Also, there are many ways to approach thesystems development process:
Packaged software
In-house development
End-user development
Outsourcing
The company also chooses between:
Modifying or enhancing existing software Replacing existing software
Reengineering its business processes
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The design team should identify a variety ofdesign alternatives and evaluate each withrespect to: How well it meets organizational and system
objectives
How well it meets user needs Whether it is economically feasible
Its advantages and disadvantages
The steering committee evaluates the
alternatives.
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
How should the communications channel beconfigured?
What type of communications channelshould be used?
Phone lines
Coaxial cable Fiber optics
Microwave
Satellite
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
How should the communications channel beconfigured?
What type of communications channel should beused?
What type of communications networkshould be used? Centralized
Decentralized
Distributed
Local area
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
How should the communications channel beconfigured?
What type of communications channel should beused?
What type of communications network should beused?
What type of storage media should be usedfor data? Tape
Disk
Diskette
Hard drive
CD
Paper
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
How should the communications channel beconfigured?
What type of communications channel should beused?
What type of communications network should beused?
What type of storage media should be used fordata?
What type of data storage structure shouldbe used?
Files
Database
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
How should the communications channel beconfigured?
What type of communications channel should beused?
What type of communications network should beused?
What type of storage media should be used fordata?
What type of data storage structure should beused?
How should files be organized andaccessed?
Random
Sequential
Indexed-sequential access
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? Keying
OCR
MICR
POS EDI
Voice
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CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? What format will the input take?
How will the system be operated? In-house Outsourcing
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? What format will the input take?
How will the system be operated?
How frequently will outputs be produced?
Instantly Hourly
Daily
Weekly
Monthly
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? What format will the input take?
How will the system be operated?
How frequently will outputs be produced?
What media will be used for output? Paper
Screen
Voice
Diskette CD
Microfilm
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CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? What format will the input take?
How will the system be operated?
How frequently will outputs be produced?
What media will be used for output? How will output be scheduled?
What format will the output take?
Narrative
Table
Graph
Electronic file or communication
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CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? What format will the input take?
How will the system be operated?
How frequently will outputs be produced?
What media will be used for output? How will output be scheduled?
What format will the output take?
What form will printed output take?
What processing mode will be used? Manual
Batch
Real time
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? What format will the input take?
How will the system be operated?
How frequently will outputs be produced?
What media will be used for output? How will output be scheduled?
What format will the output take?
What form will printed output take?
What processing mode will be used? What type of processor will be utilized?
Personal computer
Minicomputer
Mainframe
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
What media should be used to input data? What format will the input take?
How will the system be operated?
How frequently will outputs be produced?
What media will be used for output? How will output be scheduled?
What format will the output take?
What form will printed output take?
What processing mode will be used? What type of processor will be utilized?
How will software be acquired?
Canned
Custom
Modified
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
How will transactions be processed? By batch
Online
CONCEPTUAL DESIGN
CONSIDERATIONS AND ALTERNATIVES
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CONSIDERATIONS AND ALTERNATIVES
How will transactions be processed? How frequently will updates occur?
Instantly
Hourly
Daily
Weekly
Monthly
Systems
Analysis
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y
Prepare
Design
Specifications
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
Prepare
Conceptual Systems
Design report
Evaluate
Design
Alternatives
CONCEPTUAL SYSTEMS DESIGN
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Prepare design specifications Once a design has been selected, the
project team develops the conceptual
design speci f icat ionsfor the followingelements:
Output
Because output is what goes to the user and thesystem must be designed to meet user needs, the
output specifications are prepared first.
CONCEPTUAL SYSTEMS DESIGN
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Prepare design specifications Once a design has been selected, the
project team develops the conceptual
design speci f icat ionsfor the followingelements:
Output
Data storage How will data be stored to produce the desired
outputs?
CONCEPTUAL SYSTEMS DESIGN
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Prepare design specifications Once a design has been selected, the
project team develops the conceptual
design speci f icat ionsfor the followingelements:
Output
Data storage Input
What types of data must be entered to produce the
desired outputs?
CONCEPTUAL SYSTEMS DESIGN
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Prepare design specifications Once a design has been selected, the
project team develops the conceptual
design speci f icat ionsfor the followingelements:
Output
Data storage
Input Processing procedures and operations
How will data be processed and in what sequence
to produce the desired outputs?
Systems
Analysis
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Prepare
Design
Specifications
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
Prepare
Conceptual Systems
Design report
Evaluate
Design
Alternatives
CONCEPTUAL SYSTEMS DESIGN
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Prepare the Conceptual SystemsDesign Report
A conceptual systems design reportis
prepared at the end of the conceptual designphase to:
Guide physical system design activities.
Communicate how management and user
information needs will be met. Help the steering committee assess system
feasibility.
CONCEPTUAL SYSTEMS DESIGN
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The main component is a description of one ormore recommended system designs. This
description contains:
The contents of each output, database, and input.
Processing flows and the relationships among
programs, files, inputs, and outputs.
Hardware, software, and resource requirements.
Audit, control, and security processes and
procedures.
A discussion of assumptions or unresolved problems
that might affect the final design.
Learning Objective 3
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Discuss the physical system design
process and the activities in this phase
PHYSICAL SYSTEMS DESIGN
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During the physical systems design phase, thecompany determines how the conceptual AISdesign is to be implemented. The broad, user-oriented requirements of conceptual
design are translated into detailed specifications used
to code and test computer programs. Phases include:
Designing output
Creating files and databases
Designing input
Writing computer programs Developing procedures
Building in controls
Systems
Analysis
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Conceptual
Systems
Design
Output
Design
Implementation
And
Conversion
Operation
And
Maintenance
File & DB
Design
Input
Design
Program
Design
Proce-
duresDesign
Controls
Design
PhysicalSystems
Design
Systems
Analysis
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Conceptual
Systems
Design
Output
Design
Implementation
And
Conversion
Operation
And
Maintenance
File & DB
Design
Input
Design
Program
Design
Proce-
duresDesign
Controls
Design
PHYSICAL SYSTEMS DESIGN
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Output Design The objective of output design is to
determine the nature, format, content,
and timing of printed reports,documents, and screen displays.
Requires cooperation between users and
designers.
PHYSICAL SYSTEMS DESIGN
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Important design considerations include: Use of the output
Who will use it and why?
When is it needed?
What decisions will it facilitate?
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PHYSICAL SYSTEMS DESIGN
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Important design considerations include: Use of the output
Output medium
Output format Should select the format thatclearly conveys the mostinformation.
Could be:
Table
Narrative
Graphic
PHYSICAL SYSTEMS DESIGN
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Important design considerations include: Use of the output
Output medium
Output format Pre-printed Should paper output be on
preprinted form and/or
turnaround document?
PHYSICAL SYSTEMS DESIGN
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Important design considerations include: Use of the output
Output medium
Output format Pre-printed
Location Where is the output to besent?
PHYSICAL SYSTEMS DESIGN
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Important design considerations include: Use of the output
Output medium
Output format Pre-printed
Location
Access Who should be able to
access hard-copy andscreen output?
PHYSICAL SYSTEMS DESIGN
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Important design considerations include: Use of the output
Output medium
Output format Pre-printed
Location
Access Detail
Lengthy output should be preceded by an
executive summary and a table of contents.
Headings and legends organize data and
highlight important items.
Detailed info goes in an appendix.
PHYSICAL SYSTEMS DESIGN
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Important design considerations include: Use of the output
Output medium
Output format Pre-printed
Location
Access Detail
Timeliness
How often should the output be produced?
PHYSICAL SYSTEMS DESIGN
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Outputs usually fit into one of the followingfour categories:
Scheduled reports
Have pre-specified content and format.
Are prepared on a regular basis.
Examples:
Weekly sales analysis
Monthly financial statements
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PHYSICAL SYSTEMS DESIGN
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Outputs usually fit into one of the followingfour categories:
Scheduled reports
Special-purpose analysis reports Triggered exception reports
Have pre-specified content and format.
Prepared only in response to abnormal
conditions, i.e., the trigger.
Example:
Cost overruns
PHYSICAL SYSTEMS DESIGN
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Outputs usually fit into one of the followingfour categories:
Scheduled reports
Special-purpose analysis reports Triggered exception reports
Demand reports
Have pre-specified content and format.
Prepared only on request.
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Systems
Analysis
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Conceptual
Systems
Design
Output
Design
Implementation
And
Conversion
Operation
And
Maintenance
File & DB
Design
Input
Design
Program
Design
Proce-
duresDesign
Controls
Design
PHYSICAL SYSTEMS DESIGN
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File and Database Design Various company segments need to store data in
compatible formats so that data can be shared across
units.
Important file and database design considerationsinclude:
Storage medium Hard drive
Disk
Diskette
CD Tape
Paper
PHYSICAL SYSTEMS DESIGN
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File and Database Design Various company segments need to store data in
compatible formats so that data can be shared across
units.
Important file and database design considerationsinclude:
Storage medium
Processing mode Manual
Batch
Real time
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File and Database Design Various company segments need to store data in
compatible formats so that data can be shared across
units.
Important file and database design considerationsinclude:
Storage medium
Processing mode
Maintenance What procedures are needed to
effectively maintain the data?
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File and Database Design Various company segments need to store data in
compatible formats so that data can be shared across
units.
Important file and database design considerationsinclude:
Storage medium
Processing mode
Maintenance
Size How many records and how big are they?
How fast are they expected to grow?
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File and Database Design Various company segments need to store data in
compatible formats so that data can be shared across
units.
Important file and database design considerationsinclude:
Storage medium
Processing mode
Maintenance
Size
Activity level
What portion of records are added or
deleted each year?
What portion needs to be updated?
Systems
Analysis
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Conceptual
SystemsDesign
Output
Design
Implementation
And
Conversion
Operation
And
Maintenance
File & DB
Design
Input
Design
Program
Design
Proce-
duresDesign
Controls
Design
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Input Design Systems designers must identify the
different types of data input and optimal
input methods. There are two principal types of data
input:
Forms Computer screens
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Considerations in input design include: Input medium Keyboard
OCR
MICR
POS terminal EDI
Voice input
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Considerations in input design include: Input medium
Input source
Where do data originate?
Computer
Customer
Remote location
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Considerations in input design include: Input medium
Input source
Input format What format captures the data with
the least effort or cost? Source or turnaround document
Screen
Source data automation
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Considerations in input design include: Input medium
Input source
Input format
Input type What is the nature of the data?
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Considerations in input design include: Input medium
Input source
Input format
Input type
Volume How much data are to be entered?
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Considerations in input design include: Input medium
Input source
Input format
Input type
Volume
Personnel
What functions and expertise do the data
entry operators have?
Is additional training necessary?
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Considerations in input design include: Input medium
Input source
Input format
Input type
Volume
Personnel
Frequency How often is data to be entered?
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Considerations in input design include: Input medium
Input source
Input format
Input type
Volume
Personnel
Frequency
Cost
How can costs be minimized without
adversely affecting efficiency andaccuracy?
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Considerations in input design include: Input medium
Input source
Input format
Input type
Volume
Personnel
Frequency
Cost
Error detection and correction
What errors are possible?
How can they be detected and corrected?
PHYSICAL SYSTEMS DESIGN
Preprint as much data as possible.
Use appropriate weight and grade of paper.
Use bold type, double-thick lines, and shading to
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Forms DesignAlthough input is evolving toward source data
automation, forms design is still important.
Following are important principles for
designing new forms and evaluating existing
ones:
General considerations
Use bold type, double thick lines, and shading to
highlight different parts of the form. Use a standard size and one that is consistent with
requirements for filing, binding, or mailing.
If mailed to external parties, position the address for
placement in a window envelope.
Have copies of the form printed in different colors tofacilitate accurate distribution.
Include clear instructions for completing the form.
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Forms DesignAlthough input is evolving toward source data
automation, forms design is still important.
Following are important principles for
designing new forms and evaluating existing
ones:
General considerations
Introductory section of form
Place the form name at the top in bold type.
Have the forms pre-numberedconsecutively.
If distributed to external parties, have
company name and address pre-printed on
the form.
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Forms DesignAlthough input is evolving toward source data
automation, forms design is still important.
Following are important principles for
designing new forms and evaluating existing
ones:
General considerations
Introductory section of form Main body of form
Group together logically related information
(e.g., info about the customer, info about
the product).
Provide sufficient room to record each item.
Order the data items consistent with thesequence in which the data is likely to be
gathered.
Use codes and check-offs in places where
standardized explanations are likely.
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Forms DesignAlthough input is evolving toward source data
automation, forms design is still important.
Following are important principles for
designing new forms and evaluating existing
ones:
General considerations
Introductory section of form Main body of form
Conclusion section of form
Provide space for:
Recording final disposition of the form.
Approval signatures.
Dates of approval and final disposition.
A dollar or numeric total.
Clearly indicate the distribution ofeach form.
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Computer screens are most effective when the followingprinciples are used:
Organize the screen for quick, accurate, and complete entry
of the data.
Minimize input by retrieving as much as possible from
the system.
Example: If the customer number is entered, retrieve his
name/address data from the system.
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Computer screens are most effective when the followingprinciples are used:
Organize the screen for quick, accurate, and complete entry of
the data.
Enter data in the same order it appears on the document.
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Computer screens are most effective when the followingprinciples are used:
Organize the screen for quick, accurate, and complete entry of
the data.
Enter data in the same order it appears on the document.
Complete the screen from left to right and top to bottom,grouping logically related data together.
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Computer screens are most effective when the followingprinciples are used:
Organize the screen for quick, accurate, and complete entry of
the data.
Enter data in the same order it appears on the document.
Complete the screen from left to right and top to bottom,grouping logically related data together.
Design the screen so users can jump from one data entry
location to another or use a single key to go directly to
screen locations.
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Computer screens are most effective when the followingprinciples are used:
Organize the screen for quick, accurate, and complete entry of
the data.
Enter data in the same order it appears on the document.
Complete the screen from left to right and top to bottom,grouping logically related data together.
Design the screen so users can jump from one data entry
location to another or use a single key to go directly to screen
locations.
Make it easy to correct mistakes.
Use clear and explicit error messages that are consistent
on all screens.
Provide a help feature for online assistance.
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Computer screens are most effective when the followingprinciples are used:
Organize the screen for quick, accurate, and complete entry of
the data.
Enter data in the same order it appears on the document.
Complete the screen from left to right and top to bottom,grouping logically related data together.
Design the screen so users can jump from one data entry
location to another or use a single key to go directly to screen
locations.
Make it easy to correct mistakes.
Avoid clutter by restricting the amount of data on one
screen.
Limit the number of menu options on a single screen.
Systems
Analysis
C t l
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Conceptual
SystemsDesign
Output
Design
Implementation
And
Conversion
Operation
And
Maintenance
File & DB
Design
Input
Design
Program
Design
Proce-
dures
Design
Controls
Design
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Program Design Program development is one of the most time-
consuming activities in the SDLC.
A struc tured prog ramm ingprocess should be
followed: With structured programming, programs should be
subdivided into small, well-defined modules to reduce
complexity and enhance reliability and modifiability.
Modules should interact with a control module rather than
with each other. To facilitate testing and modification, each module should
have only one entry and exit point.
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To improve software quality, organizationsshould develop programming standards (rules
for writing programs).
Contributes to consistency among programs.
Makes them easier to read and maintain.
Consider doing structured program walk-
throughs to find incorrect logic, errors,
omissions, or other problems.
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Program preparation time may range from a fewdays to a few years, depending on complexity.
Though accountants need not be programmers,
they should understand how software is created.
The following slides discuss the eight steps fordeveloping software and where these steps take
place in the SDLC.
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Systems
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STEP ONE: Determine userneeds.
Occurs during the systems analysis
stage of the SDLC.
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Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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STEP THREE: Write the programcode.
Design in increasing levels of detail,
known as hierarchical prog ram
design. Begun during systems design and
completed during systems
implementation.
Systems
Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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STEP FOUR T t th dSystems
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STEP FOUR: Test the program code.
Debuggingis discovering and
eliminating program errors.
Desk checkinghappens after a
program is coded and involves a
visual and mental review to discover
programming errors.
Programs are tested for logic errors
using test data that simulates both
valid transactions and all possible
error conditions.
Systems
Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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Large programs are often testedin three stages:
Individual program modules.
The linkages between the module
and the control module. The interfaces between the
program being tested and other
application programs.
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Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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Errors need to be found as soonas possible in the development
process.
Errors discovered late cost 80-
1000% more to fix than thosefound early.
Systems
Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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STEP FIVE: Document theprogram.
Documentation explains how
programs work and helps
correct and resolve errors. Includes flowcharts, record
layouts, E-R diagrams, REA
data models, narrative
descriptions of the system, etc.,
organized in a manual.
Systems
Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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STEP SIX: Train program users. Often uses the program
documentation.
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Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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STEP SEVEN: Install the system.-All components are brought
together, and the company
begins to use the system.
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Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
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STEP EIGHT: Use andmodify the system.
Program maintenanceis aresponse to any factors that
require program revision. Includes requests for:
New or revised reports.
Changes in input, file content, or
values such as tax rates. Error detection and correction.
Conversion to new hardware.
Systems
Analysis
Conceptual
Design
Physical
Design
Implementation
And
Conversion
Operation
And
Maintenance
Systems
Analysis
Conceptual
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Conceptual
SystemsDesign
Output
Design
Implementation
And
Conversion
Operation
And
Maintenance
File & DB
Design
Input
Design
Program
Design
Proce-
dures
Design
Controls
Design
PHYSICAL SYSTEMS DESIGN
Procedures Design
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Procedures Design
Individuals who interact with a newly-designed AIS need procedures to cover: Input preparation
Transaction processing Error detection and correction
Controls
Reconciliation of balances
Database access Output preparation and distribution
Computer operator instructions
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Procedures may take the form of: System manuals
User instruction classes
Training materials
Online help screens
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Analysis
Conceptual
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p
SystemsDesign
Output
Design
Implementation
And
Conversion
Operation
And
Maintenance
File & DB
Design
Input
Design
Program
Design
Proce-
dures
Design
Controls
Design
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Controls Design Improperly controlled input, processing, anddatabase functions produce information ofquestionable value.
Controls must be built into an AIS to ensureits effectiveness, efficiency, and accuracy.These controls should: Minimize errors
Detect and correct errors when they do occurAccountants play a vital role in this area.
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Important control concerns that must beaddressed include:
Validity Are all interactions valid?
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Important control concerns that must beaddressed include:
Validity
Authorization
Are input, processing, storage, and
output activities authorized by the
appropriate managers?
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Important control concerns that must beaddressed include:
Validity
Authorization
Accuracy Is input verified to ensure accuracy? What controls ensure that data is not
lost when passing between processing
activities?
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Important control concerns that must beaddressed include:
Validity
Authorization
Accuracy Security
Is the system protected against:
Unauthorized physical and logical access to prevent
improper use, alteration, destruction, or disclosure ofinformation and software?
Theft of system resources?
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Important control concerns that must beaddressed include:
Validity
Authorization
Accuracy Security
Numerical control
Are documents pre-numbered to prevent errors or
intentional misuse and to detect when documents aremissing or stolen?
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Important control concerns that must beaddressed include:
Validity
Authorization
Accuracy Security
Numerical control
Availability
Is the system available as set forth in agreements?
Can users enter, update, and retrieve data during those
times?
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Important control concerns that must beaddressed include:
Validity
Authorization
Accuracy Security
Numerical control
Availability
Maintainability
Can the system be modified without affecting system
availability, security, and integrity?
Are only authorized, tested, and documented changesmade to the system and data?