Major Topics

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Major Topics

• Information systems
• Integrating New Technology
• Phases of analysis and design
• System maintenance
• CASE tools

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Information

• Information is an organizational resource which
  must be managed as carefully as other resources
• Costs are associated with information processing
• Information processing must be managed to take
  full advantage of its potential

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Categories

• Eight categories of Information systems
• Transaction processing systems (TPS)
• Office automation systems (OAS)
• Knowledge work systems (KWS)
• Management information systems (MIS)
• Decision support systems (DSS)
• Expert systems (ES)
• Group decision support systems (GDSS)
• Executive support systems (EES)

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Level of Categories

• Figure 1.1 The computer
• analyst may be involved
• with any of or all these
• systems

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Transaction Processing Systems (TPS)

• TPS are computerized information systems
  developed to process large amount of data for
  routine business transactions
• TPS reduces the time once required to perform the
  task manually
• TPS permits the organization to interact with
  external environment
• Example Inventory or Payroll system

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Office Automation Systems (OAS) and Knowledge
Work Systems (KWS)

• Office Automation Systems (OAS)
• Includes analysis of information so as to
  transform data or manipulate it in some way
  before sharing or formally disseminating it
• Example Word processing, spreadsheets, desktop
  publishing, electronic scheduling, communication
  through voice email, email and voice conference
  etc.
• Knowledge Work Systems (KWS)
• Supports professionals (scientists, engineers,
  doctors) by aiding them to create new knowledge
• Example Scientific analysis

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Management Information Systems (MIS)

• MIS supports broader spectrum of organizational
  tasks than TPS, including decision analysis and
  decision making
• MIS users share a common database to access
  information
• MIS outputs information that is used in decision
  making
• Example Account management system of
  Internet users

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Decision Support systems (DSS)

• DSS is similar to the traditional MIS because
  they both depend on a database as a source of
  data
• Again, DSS departs from MIS in that DSS
  emphasizes the support of decision making in all
  its phases
• Example Production increase decision by
  trend analysis

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Expert Systems

• Expert system is a very special class of
  information system which is capable of generating
  solutions to problems with the aid of Artificial
  Intelligence (AI)
• An expert system (also called a knowledge based
  system) uses the knowledge of an expert for
  solving a particular problem
• Example News Categorization software

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Group Decision Support Systems (GDSS) and
Computer Supported Collaborative Work Systems
(CSCWS)

• Group Decision Support Systems
• GDSS are intended to bring a group together to
  solve a problem with the help of various support
  such as polling, questionnaires, brainstorming
  etc.
• Computer Supported Collaborative Work Systems
• CDCWS is a more general term of GDSS
• CSCWS may include software support called
  groupware for team collaboration via network
  computers
• Example video conferencing and web survey system

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Executive Support Systems (ESS)

• It helps executives to make decisions on
  strategic level
• It may provide graphical representation and
  communication support at board meeting required
  to make strategic decision
• Example New product launching decision

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Integrating New Technologies

• New technologies are being integrated into
  traditional systems
• E-commerce uses the Web to perform business
  activities
• Enterprise Resource Planning (ERP) has the goal
  of integrating many different information systems
  within the corporation
• Wireless and handheld devices, including mobile
  commerce (m-commerce)
• Open source software

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Integrating New Technologies

• Figure 1.2 Integrating
• Technologies

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E-Commerce Application and Web Systems

• Many businesses has found The Internet as
• their most favored way to pursue business
• growth because of the following advantages
• Increase awareness of the availability of the
  service, product, industry, person, or group
• 24-hour access for users
• Standardizing the design of interface
• Creating a global system rather than remain local

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Enterprise Resource Planning (ERP) Systems

• Many organizations predicts potential benefits
  from the integration of many information systems
  existing on different management levels.
• ERP systems are designed to perform this
  integration
• Example SAP, PeopleSoft and packages from Oracle

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Systems for Wireless and Handheld Devices

• System analyst may be asked to design standard or
  wireless communication network that integrate
  voice, video and email into organizational
  intranet
• System analyst may also be asked to develop
  intelligent agents to assist the user of PDA or
  cell phone
• Wireless communication is referred as m-commerce
  (mobile commerce)

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Open Source Software

• An alternative of traditional software
  development (where proprietary code is hidden
  from the users) is called open source software
• Open source software is free to distribute, share
  and modify its source code
• It makes money by providing services, customized
  program and support.
• Open source software are widely used in handheld
  and mobile devices.
• Example Linux Operating System
• Apache Web Server

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Nature of Analysis and Design

• A systematic approach to
• identify problems, opportunities, and objectives
  
• analyze the information flows in organizations
  and
• design computerized information systems to solve
  a problem.

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Systems Analyst

• Systems analysts act as
• Outside consultants to businesses
• Supporting experts within a business
• Change agents
• Analysts are problem solvers, and require
  communication skills
• Analysts must be ethical with users and customers

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Systems Development Life Cycle (SDLC)

• SDLC is a systematic approach for solving
  business problems.
• It is divided into seven phases.
• Although each phase is presented discretely, it
  is never accomplished as a separate step. Instead
  separate activity can occur simultaneously

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Systems Development Life Cycle (SDLC)

• Figure 1.3 Phases of SDLC

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Phase 1 Identifying Problems, Opportunities and
Objectives

• Personnel involved
• Analyst
• User management
• System management
• Activities
• Interviewing user management
• Summarizing the knowledge obtained
• Estimating the scope of the project
• Documenting the results
• Output Feasibility report containing problem
  definition and
• objectives
• Decision Management then make decision whether
  to proceed with
• the proposal or not

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Phase 2 Determining Information Requirement

• Personnel Involved
• Information Analyst (IA)
• User operation managers and operation workers
• Systems management
• Activity
• Interview management, operations personnel
• Gather systems/operating documents
• Use questionnaires
• Observe the system and personnel involved
• Learn the who, what, where, when, and how, and
  the why for each of these
• Output Analyst understands how the business
  functions and gets enough information
  about the people, goals,
• data and procedure involved

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Phase 3 Analyzing System Needs

• Personnel Involved
• Analyst (IA)
• User management
• Systems management
• Activity
• Create data flow diagrams
• Document procedural logic for data flow diagram
  processes
• Complete the data dictionary
• Make semi-structured decisions (condition
  alternatives)
• Prepare and present the system proposal
• Recommend the optimal solution to management

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Phase 4 Designing the Recommended System

• Personnel involved
• Analyst
• System designer
• User operation managers and operation workers
• System management
• Activity
• Design the user interface
• Design output
• Design input
• Design system controls
• Design files and/or database
• Produce program specifications
• Produce decision trees or tables
• Backup procedure

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Phase 5 Developing and Documenting Software

• Personnel involved
• Analyst
• System designer
• Programmers
• Systems management
• Activity
• System analyst designs computer programs using
  structure charts, and pseudo code etc.
• Programmers write computer programs
• Document software with help files, procedure
  manuals, and Web sites with Frequently Asked
  Questions

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Phase 6 Testing and Maintaining the System

• Personnel involved
• Analyst
• System designer
• Programmers
• Systems management
• Activity
• Test and debug computer programs
• Test the computer system
• Enhance system
• Maintenance of the system begins from this phase

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Phase 7 Implementing and Evaluating the System

• Personnel involved
• Analyst
• System designer
• Programmers
• User operation managers and operation workers
• Systems management
• Activity
• Train users
• Analyst plans smooth conversion from old system
  to new system
• Purchase and install new equipment
• Install system
• Review and evaluate system

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Maintenance

• Maintenance is performed for 2 reasons
• System maintenance
• Removing undetected errors, and
• Enhancing existing software
• Systems are enhanced for the following reasons
• Adding additional features to the system
• Business and governmental requirements change
  over time
• Technology, hardware, and software are rapidly
  changing

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Impact of Maintenance

• Figure 1.4 Time spent on system maintenance

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Impact of Maintenance
Figure 1.5 Resource consumption over the
system life
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CASE Tools

• CASE tools are automated, microcomputer-based
  software packages for systems analysis and design
• Four reasons for using CASE tools are
• To increase analyst productivity
• Facilitate communication among analysts and users
• Providing continuity and integrity among life
  cycle phases
• To assess the maintenance changes

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CASE Tool Categories

• CASE tools may be divided into several categories
• Upper CASE (also called front-end CASE) tools,
  used to perform analysis and design
• Lower CASE (also called back-end CASE). These
  tools generate computer language source code from
  CASE design.
• Integrated CASE, performing both upper and lower
  CASE functions.

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Upper CASE

• Upper CASE tools
• Create and modify the system design
• Store data in a project repository
• The repository is a collection of records,
  elements, diagrams, screens, reports, and other
  project information
• These CASE tools model organizational
  requirements and define system boundaries

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Upper Case

• Figure 1.6 The repository concept

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Lower CASE

• Lower CASE tools generate computer source code
  from the CASE design
• Source code may usually be generated in several
  languages
• Advantages of generation code
• decrease development time
• More programming language support
• Free from program coding error

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Traditional VS Case system development life cycle
Figure 1.7 Traditional VS Case SDLC
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Reverse Engineering

• Reverse engineering is generating the CASE design
  from computer program code
• Source code is examined, analyzed, and converted
  into repository entities

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Advantages of Reverse Engineering

• Reduced system maintenance time, freeing up time
  for new development
• Program documentation is produced for loosely
  documented programs
• Structured programs may be generated from
  unstructured, older programs
• Future system maintenance is easier to implement
• Unused portions of programs may be eliminated

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Object-Oriented Analysis and Design

• Object-oriented (O-O) analysis and design is used
  to build object-oriented programs
• This includes not only data but the instructions
  about operations that manipulate the data

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Alternative Methodologies

• Alternatives to SDLC
• Prototyping
• ETHICS
• Soft System Methodology
• Multiview

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