System Development

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System Development
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• Overview of Information Systems (IS)
• Information Technology Concepts
• Business and Specialized IS
• System Development
• IS in Business and Society

Components of an IS
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Overview

• Participants
• Information Systems Planning
• Investigation and Analysis
• Design and Implementation
• Maintenance and Review
• Tools

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Participants
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An Overview of Systems Development

• Today, users of information systems are involved
  in their development
• This chapter will
• Help you avoid systems development failures or
  projects that go over budget

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Participants in Systems Development

• Development team
• Determines objectives of the information system
• Delivers system that meets objectives
• Project
• Planned collection of activities that achieves a
  goal
• Project manager
• Responsible for coordinating all people and
  resources needed to complete a project on time

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Participants in Systems Development (continued)

• Stakeholders
• People who ultimately benefit from project
• Users
• People who will interact with the system
  regularly
• Systems development specialists
• Systems analysts
• Programmers

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Participants in Systems Development (continued)
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Information Systems Planning
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Initiating Systems Development

• Systems development initiatives
• Arise from all levels of an organization
• Can be planned or unplanned
• Number of reasons for initiating systems
  development projects
• Mergers, acquisitions, federal regulations, etc.

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Information Systems Planning and Aligning
Corporate and IS Goals

• Information systems planning
• Translating strategic and organizational goals
  into systems development initiatives
• Aligning organizational goals and IS goals
• Critical for successful systems development
  effort
• Developing a competitive advantage
• Creative analysis
• Critical analysis

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Information Systems Planning
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Aligning Corporate and IS Goals
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Establishing Objectives for Systems Development

• Mission-critical systems
• Play pivotal role in organizations continued
  operations and goal attainment
• Critical success factors (CSFs)
• Factors essential to success of a functional area
  of an organization

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Establishing Objectives for Systems Development
(continued)

• Performance objectives
• Output quality or usefulness
• Output accuracy
• Speed at which output is produced
• Scalability of resulting system
• Risk of the system

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Establishing Objectives for Systems Development
(continued)

• Cost objectives
• Development costs
• Costs of uniqueness of system application
• Fixed investments in hardware and related
  equipment
• Ongoing operating costs

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Systems Development Life Cycles

• The later in the SDLC an error is detected, the
  more expensive it is to correct
• Previous phases must be reworked
• More people are affected

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Systems Development Life Cycles (continued)
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Systems Development Life Cycles (continued)

• Common systems development life cycles
• Traditional
• Prototyping
• Rapid application development (RAD)
• End-user development

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The Traditional Systems Development Life Cycle

• Systems investigation
• Identifies problems and opportunities and
  considers them in light of business goals
• Systems analysis
• Studies existing systems and work processes to
  identify strengths, weaknesses, and opportunities
  for improvement
• Systems design
• Defines how the information system will do what
  it must do to obtain the problems solution

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The Traditional Systems Development Life Cycle
(continued)

• Systems implementation
• Creates or acquires various system components
  detailed in systems design, assembles them, and
  places new or modified system into operation
• Systems maintenance and review
• Ensures the system operates as intended
• Modifies the system so that it continues to meet
  changing business needs

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The Traditional Systems Development Life Cycle
(continued)
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The Traditional Systems Development Life Cycle
(continued)
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Prototyping

• An iterative approach
• Operational prototype
• Prototype that works
• Accesses real data files, edits input data, makes
  necessary computations and comparisons, and
  produces real output
• Nonoperational prototype
• A mock-up, or model
• Includes output and input specifications and
  formats

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Prototyping (continued)
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Prototyping (continued)
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Prototyping (continued)
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Rapid Application Development, Agile Development,
Joint Application Development, and Other Systems
Development Approaches

• Rapid application development (RAD)
• Employs tools, techniques, and methodologies
  designed to speed application development
• Makes extensive use of the joint application
  development (JAD)
• Other approaches to rapid development
• Agile development
• Extreme programming (XP)

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Rapid Application Development, Agile Development,
Joint Application Development, and Other Systems
Development Approaches (continued)
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The End-User Systems Development

• End-user systems development
• Systems development project in which business
  managers and users assume the primary effort
• Disadvantages
• Some end users do not have the training to
  effectively develop and test a system

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Outsourcing and On-Demand Computing

• Reduces costs
• Obtains state-of-the-art technology
• Eliminates staffing and personnel problems
• Increases technological flexibility

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Outsourcing and On-Demand Computing (continued)
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Factors Affecting Systems Development Success

• Successful systems development
• Delivers a system that meets user and
  organizational needs on time and within budget
• Critical for most systems development projects
• Getting users and stakeholders involved

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Degree of Change

• Continuous improvement projects
• High degree of success
• Relatively modest benefits
• Managing change
• Ability to recognize and deal with existing or
  potential problems

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Degree of Change (continued)
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Quality and Standards

• Quality of project planning
• Bigger the project, the more likely that poor
  planning will lead to significant problems
• Capability Maturity Model (CMM)
• One way to measure organizational experience

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Quality and Standards (continued)
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Use of Project Management Tools

• Project schedule
• Detailed description of what is to be done
• Project milestone
• Critical date for completion of a major part of
  the project
• Project deadline
• Date that the entire project is to be completed
  and operational
• Critical path
• Activities that, if delayed, would delay the
  entire project

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Use of Project Management Tools (continued)

• Program Evaluation and Review Technique (PERT)
• Creates three time estimates for an activity
• Shortest possible time
• Most likely time
• Longest possible time
• Gantt chart
• Graphical tool used for planning, monitoring, and
  coordinating projects

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Use of Computer-Aided Software Engineering (CASE)
Tools

• CASE tools
• Automate many tasks required in a systems
  development effort
• Encourage adherence to SDLC
• Companies that produce CASE tools
• Accenture, Microsoft, and Oracle

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Use of Computer-Aided Software Engineering (CASE)
Tools (continued)
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Object-Oriented Systems Development

• Combines logic of systems development life cycle
  with power of object-oriented modeling and
  programming
• OOSD tasks
• Identify potential problems and opportunities
  that would be appropriate for OO approach
• Define user requirements

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Object-Oriented Systems Development (continued)

• OOSD tasks (continued)
• Design system
• Program or modify modules
• User evaluation
• Periodic review and modification

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Systems Investigation

• What primary problems might a new or enhanced
  system solve?
• What opportunities might a new or enhanced system
  provide?
• What new hardware, software, databases,
  telecommunications, personnel, or procedures will
  improve an existing system or are required in a
  new system?
• What are the potential costs (variable and
  fixed)?
• What are the associated risks?

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Initiating Systems Investigation

• Systems request form
• Submitted by someone who wants IS department to
  initiate systems investigation
• Information included
• Problems in or opportunities for system
• Objectives of systems investigation
• Overview of proposed system
• Expected costs and benefits of proposed system

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Participants in Systems Investigation

• Members of development team change from phase to
  phase
• Keys to successful investigation teams
• Cooperation and collaboration

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Participants in Systems Investigation (continued)
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Feasibility Analysis

• Technical feasibility
• Economic feasibility
• Net present value
• Legal feasibility
• Operational feasibility
• Schedule feasibility

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Feasibility Analysis (continued)
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Object-Oriented Systems Investigation

• Object-oriented approach
• Can be used during all phases of systems
  development
• Use case diagram
• Part of the Unified Modeling Language (UML) that
  is used in object-oriented systems Development

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Object-Oriented Systems Investigation (continued)
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The Systems Investigation Report

• Summarizes results of systems investigation
• Summarizes the process of feasibility analysis
• Recommends a course of action
• Continue on into systems analysis
• Modify the project in some manner
• Drop the project
• Reviewed by steering committee

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The Systems Investigation Report (continued)
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Systems Analysis

• Overall emphasis of analysis
• Gathering data on existing system
• Determining requirements for new system
• Considering alternatives
• Investigating feasibility of solutions
• Primary outcome of systems analysis
• Prioritized list of systems requirements

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General Considerations

• Steps of a formalized analysis procedure
• Assembling participants for systems analysis
• Collecting data and requirements
• Analyzing data and requirements
• Preparing a report on existing system, new system
  requirements, and project priorities

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Participants in Systems Analysis

• Includes members of the original investigation
  team
• Systems analysis team develops
• List of objectives and activities
• Deadlines
• Statement of resources required
• Major milestones

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Data Collection

• Identifying sources of data
• Internal and external sources
• Collecting data
• Interviews
• Direct observation
• Questionnaires

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Identifying Sources of Data
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Collecting Data
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Data Analysis

• Data modeling
• Activity modeling
• Application flowcharts
• Grid charts
• CASE tools

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Data Analysis (continued)
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Requirements Analysis

• Determination of user, stakeholder, and
  organizational needs
• Techniques
• Asking directly
• Critical success factors (CSFs)
• IS plan
• Screen and report layout
• Requirements analysis tools

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Requirements Analysis (continued)
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Object-Oriented Systems Analysis

• Identify problems or potential opportunities
• Identify key participants and collect data
• With the OO approach a class is used to describe
  different types of objects

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Object-Oriented Systems Analysis (continued)
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The Systems Analysis Report

• Elements
• Strengths and weaknesses of existing system from
  a stakeholders perspective
• User/stakeholder requirements for new system
• Organizational requirements for new system
• Description of what new information system should
  do to solve the problem

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The Systems Analysis Report (continued)
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Systems Design

• Answers the question
• How will the information system solve a problem?
• Results in a technical design that
• Details system outputs, inputs, and user
  interfaces
• Specifies hardware, software, databases,
  telecommunications, personnel, and procedures
• Shows how these components are related

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Logical and Physical Design

• Logical design
• Describes functional requirements of a system
• Physical design
• Specifies the characteristics of the system
  components necessary to put the logical design
  into action

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Object-Oriented Design

• Using the OO approach
• You can design key objects and classes of objects
  in the new or updated system
• Process includes considering the problem domain,
  the operating environment, and the user interface
• During design phase consider the sequence of
  events that must happen for the system to
  function correctly

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Object-Oriented Design (continued)
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Interface Design and Controls

• System characteristics
• Sign-on procedure
• Interactive processing
• Help facility
• Lookup tables
• Restart procedure

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Interface Design and Controls (continued)
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Interface Design and Controls (continued)
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Design of System Security and Controls

• Preventing, detecting, and correcting errors
• Disaster planning and recovery
• Disaster planning
• Disaster recovery
• Systems controls
• Closed shops
• Open shops
• Deterrence controls

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Environmental Design Considerations

• Environmental design
• Also called green design
• Involves systems development efforts that slash
  power consumption, require less physical space,
  and result in systems that can be disposed in a
  way that doesnt negatively affect the environment

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Generating Systems Design Alternatives

• Request for proposal (RFP)
• Document that specifies required resources such
  as hardware and software in detail
• Financial options
• Purchase, lease, or rent
• Evaluating and selecting a systems design
• Preliminary evaluation
• Final evaluation

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Generating Systems Design Alternatives (continued)
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Evaluation Techniques

• Group consensus
• Cost/benefit analysis
• Benchmark tests
• Point evaluation

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Evaluation Techniques (continued)
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Evaluation Techniques (continued)
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Freezing Design Specifications

• User agrees in writing that the design is
  acceptable
• Other organizations
• Allow or even encourage design changes

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Freezing Design Specifications (continued)
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The Contract

• Vendors provide standard contracts to protect
  themselves
• Typically, the request for proposal becomes part
  of the contract

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The Design Report

• Primary result of systems design
• Reflects decisions made and prepares the way for
  systems implementation

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The Design Report (continued)
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Systems Implementation

• Includes
• Hardware acquisition
• Programming and software acquisition or
  development
• User preparation
• Hiring and training of personnel
• Site and data preparation
• Installation, testing, start-up, and user
  acceptance

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Acquiring Software Make or Buy?

• Make-or-buy decision
• Whether to obtain software from external or
  internal sources
• Externally acquired software and Software as a
  Service (SaaS)
• Commercial off-the-shelf (COTS) development
  process
• In-house developed software
• CASE and object-oriented approaches
• Cross-platform development
• Integrated development environment

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Acquiring Database and Telecommunications Systems

• Databases
• A blend of hardware and software
• Virtual databases and database as a service
  (DaaS)
• Popular ways to acquire database capabilities

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User Preparation

• Readying managers, decision makers, employees,
  other users, and stakeholders for new systems
• Important, but often ignored area of systems
  implementation

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IS Personnel Hiring and Training

• Eventual success of any system depends on how it
  is used by the IS personnel within the
  organization
• Training programs should be conducted for the IS
  personnel who will be using the computer system
• More detailed than user training in the technical
  aspects of the systems

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Site Preparation

• Preparation of the location of a new system
• Larger systems may require special equipment
• Developing IS sites that are energy efficient is
  important

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Data Preparation

• Also called data conversion
• Ensuring all files and databases are ready to be
  used with new computer software and systems

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Installation

• Process of physically placing computer equipment
  on the site and making it operational
• Normally, manufacturer is responsible for
  installing computer equipment
• Someone from the organization (usually IS
  manager) should oversee the process

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Testing

• Unit testing
• System testing
• Volume testing
• Integration testing
• Acceptance testing
• Alpha testing
• Beta testing

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Start-Up

• Process of making the final tested information
  system fully operational
• Approaches
• Direct conversion (plunge, direct cutover)
• Phase-in approach (piecemeal)
• Pilot start-up
• Parallel start-up

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User Acceptance

• Formal agreement signed by user that states that
  a phase of installation or the complete system is
  approved
• Legal document that removes or reduces IS
  vendors liability

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Systems Operation and Maintenance

• Systems operation
• Use of a new or modified system
• Systems maintenance
• Checking, changing, and enhancing the system to
  make it more useful in achieving user and
  organizational goals

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Reasons for Maintenance

• Changes in business processes
• New requests from stakeholders, users, and
  managers
• Bugs or errors in program
• Technical and hardware problems
• Corporate mergers and acquisitions
• Government regulations

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Types of Maintenance

• Slipstream upgrade
• Usually requires recompiling all the code
• Patch
• Minor change to correct a problem
• Release
• Significant program change
• Version
• Major program change

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The Request for Maintenance Form

• Form authorizing modification of programs
• Usually signed by a business manager
• IS group
• Reviews form
• Identifies programs to be changed
• Determines programmer to be assigned to task
• Estimates expected completion date
• Develops a technical description of change

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Performing Maintenance

• Maintenance team
• Responsible for modifying, fixing, and updating
  existing software
• Maintenance function
• Becoming more automated

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The Relationship Between Maintenance and Design

• Programs are expensive to develop, but they are
  even more expensive to maintain
• Determining factor in decision to replace a
  system
• The point at which it is costing more to fix than
  to replace

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The Relationship Between Maintenance and Design
(continued)
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Systems Review

• Final step of systems development
• Analyzes systems to make sure that they are
  operating as intended

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Types of Review Procedures

• Event-driven review
• Triggered by a problem or opportunity
• Time-driven review
• Performed after a specified amount of time

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Types of Review Procedures (continued)
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System Performance Measurement

• Monitoring the system
• Number of errors encountered
• Amount of memory required
• Amount of processing or CPU time needed
• Other problems
• System performance products
• Software that measures all components of the
  computer-based information system

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Summary

• Systems development team
• Stakeholders, users, managers, systems
  development specialists, and various support
  personnel
• Five phases of the traditional SDLC
• Investigation, analysis, design, implementation,
  and maintenance and review
• Advantages of the traditional SDLC
• Provides for maximum management control
• Creates considerable system documentation
• Produces many intermediate products for review

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Summary (continued)

• Rapid application development (RAD)
• Reduces paper-based documentation
• Automates program source code generation
• Facilitates user participation in development
  activities
• Factors that affect systems development success
• Degree of change introduced by the project
• Continuous improvement and reengineering
• Use of quality programs and standards

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Summary (continued)

• Participants in systems investigation
• Stakeholders, users, managers, employees,
  analysts, and programmers
• Data collection methods
• Observation, interviews, questionnaires, and
  statistical sampling
• Requirements analysis
• Determines the needs of users, stakeholders, and
  the organization in general

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Summary

• Purpose of systems design
• To prepare detailed design needs for a new system
  
• Logical and physical design
• Can be accomplished using the traditional systems
  development life cycle or the object oriented
  approach
• Disaster recovery
• Important aspect of systems design

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Summary (continued)

• Purpose of systems implementation
• To install the system and make everything,
  including users, ready for its operation
• Software can be purchased from vendors or
  developed in-house
• Cross-platform development and integrated
  development environments (IDEs)
• Make software development easier and more thorough

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Summary (continued)

• Systems operation
• Use of a new or modified system
• Maintenance
• Can be as simple as a program patch to the more
  complex upgrading of software with a new release
  from a vendor
• Systems review
• Process of analyzing and monitoring systems to
  make sure that they are operating as intended