01 isad-information system analysis and design intro by S. A. AHSAN RAJON

1. INFORMATION SYSTEM ANALYSIS AND DESIGN S. A. AHSAN RAJON Ahsan.rajon@gmail.com http://sites.google.com/site/ahsanrajon +88-01911510286

2. About the course… SAD System Analysis and Design ISAD Information System Analysis and Design SAD

3. Welcome… Easy course; but uninteresting; No math; No programming; No logic; Simply “voluminous” texts. Traditional learning… How to do well in exam? Understand the topic… Note down the “Key points” extracted from the texts. Try to match with your usual “day-to-day” concept.

4. CLASS TEST… At LEAST THREE class tests… If you want more; ... [ ??? ] Class Test Schedule Week will be fixed by me…. Dates will be SELECTED by you DATES are absolute; not even ask…

5. MATERIALS… BOOKS SYSTEMS ANALYSIS AND DESIGN Author: Elias M. Awad Edition: Second Edition or Any recent Publisher: Galgotia Publications Modern System analysis and Design Author: Jeffery A. Hoffer, Joey F. George, Joseph S. Valacich, Prabin K. Panigrahi Edition: Fourth Edition or recent Publisher: Pearson SYSTEM ANALYSIS AND DESIGN METHODS Author: Jeffery L. Whitten Edition: Fifth Edition or recent Publisher: McGraw Hill

6. MATERIALS… Reference Book Information Systems: A Management Perspective Author: Steven Alter Edition: Third Edition or Any recent Publisher: Pearson Education OTHER RESOURCES Should be provided Lecture Slides Oops!! SAD with SAD lecture Slides…

7. Monitoring System Intelligent Systems Hardware System Integration System Validation System Information System Verification System Testing System Interactive Testing SYSTEMS Production System Implementation System Management System Structured System Software Systems Ad-hoc System

8. Which should be focused??? Systems Concepts System Development Life Cycle Role of System Analyst System planning Information gathering Tools for structured analysis Cost and benefit analysis System and system-component design Miscellaneous

9. Why do we need to study this course? Software Systems are based on Information Systems Development of Software requires understanding the “existing system set-up” Revealing existing set up requires you to understand the organizational paradigm. How to have requirement Analysis? Then you need data collection How to collect data? How to record Data? How to get a result from that data?

10. Case Study… Consider University Management System. Employee information and Payroll management System. Company Automation System/production control system National ID project. Electronic voting system. SMS-based information management system.

11. The course will focus on … For any System What is the current system? How the current system works? What are the advantages & disadvantages i.e. problems of present system? How Information Technology may be applied (if not applied in the current system)? Or how the adopted Information Technology based System may be enhanced? Which advantages are obtained by applying the new systems. What are the limitations/disadvantages/pitfalls of new systems? How to administer/Manage the new system?

12. SYSTEM… Derived from Greek word “systema” which means An organized relationship among functioning units or components. A system exists because it is designed to achieve one or more objectives. A system is an orderly grouping of interdependent componentslinked together according to a plan to achieve a specific objective.

13. SYSTEM… Component may refer to Physical parts engines, wings of aircraft or wheels of a car Managerial steps Planning, Organizing, Directing and Controlling Or a subsystem of multilevel structure

14. SYSTEM… Components of a system may be simple or complex, basic or advanced. There may be a single computer or even be a series of intelligent terminals linked to a mainframe. In either case, each component is part of the total system and has to share do its share of work for the system to achieve the intended goal.

15. Implications of Studying a System A system must be designed to achieve a predefined objective. Interrelationships and interdependence must exist among the components. The objectives of the organization as a whole has a higher priority than the objectives of the subsystem.

16. Characteristics of a SYSTEM… Organization Interaction Interdependence Integration Central Objective

17. System Characteristics: Organization… Implies Structure and Order Arrangements that helps to achieve objectives Hierarchical Relationship Such Arrangement portraying a system—subsystem relationship Defines authority structure Specifies formal flow of communication Formulizes the chain of command

18. System Characteristics: Interaction… Refers to the manner in which each component functions with other components of the system. Interrelationship among the central processing unit, memory and other hardware components enables the computer system to perform.

19. System Characteristics: Interdependence… Interdependence means that parts of the organization or computer system works together. They are coordinated and linked together according to a plan. One subsystem depends on input of another subsystem for proper functioning; that is output of one subsystem is required input of another subsystem. No subsystem can function in isolation.

20. System Characteristics: Interdependence Task interdependence in computer based systems User area System Analysis Design Programming Operations

21. System Characteristics: Interdependence… University Admission Courses Accounts Grants Administration Internal earnings Finance Research Outcome personnel Consultancy personnel Accounts Major Subsystem Employment Minor Subsystem Safety Benefits Miscellaneous Intermediate Subsystem

22. System Characteristics: Integration… Refers to the holism of a system. Integration is concerned with how a system is tied together. More than sharing a physical part. It means that parts of the system works together within the system even though the each part performs a unique function.

23. System Characteristics: Central Objective… Objectives may be real or stated. Achievement of one objective may be a must for moving towards achievement of another one.

24. INFORMATION SYSTEM… An information system is an arrangement of people, data, process, information presentation and information technology that interact to support an improved day-to-day operations in a business as well as support the problem solving and decision making needs to management and users. [Whitten]

25. INFORMATION SYSTEM… Information system may be defined as a set of devices, procedures and operating systems designed around user based criteria to produce information and communicate it to the users for planning, control and performance

26. INFORMATION TECHNOLOGY… Information technology is a contemporary term that describes the combination of computer technology (hardware and software) with telecommunication technology (data, voice networks)

27. INFORMATION SYSTEM ANALYSIS AND DESIGN… Information system analysis and design is the complex organizational process whereby computer based organizational systems are developed and maintained. Main goal is to improve employee efficiency by applying software solutions to key business tasks A structured approach must be used in order to ensure success [ Hoffer ]

28. Types of Systems Types of Systems Physical and abstract Open or closed Man-made information system

29. Type of Sys: PHYSICAL & ABSTRACT SYSTEMS… PHYSICAL SYSTEMS… Tangible entities; may be static or dynamic in operation E.g. in computer centers, computer hardware are static, programs stored into computers are dynamic Data, programs, output and applications change as users’ demands ABSTRACT SYSTEMS Conceptual or non-physical entities E.g. model; representation of real or planned systems.

30. Type of Sys: PHYSICAL & ABSTRACT SYSTEMS… TYPES of SYSTEM MODELS Schematic Model Two dimensional chart describing system elements and linkage Flow-System Model Concerned with flow of information Static system model Exhibits pair relationship; e.g. activity-time or cost-quantity Gantt chart Dynamic System Model Describes ongoing consistently changing system Trend analysis, probabilistic model.

31. Type of Sys: OPEN or CLOSED SYSTEMS… Open Systems Permits interactions across its boundaries. Receives input from and delivers output to outside. Information system falls into this category since it must adapt to the changing demands of the user. Closed Systems Isolated from environmental influences. In reality completely closed system is rare.

32. Type of Sys: OPEN or CLOSED SYSTEMS… CHARACTERISTICS OF OPEN SYSTEMS Input from outside Entropy Process, Output and Cycles Differentiation Equi-finality No matter how you reach the destination; the matter is, the costs and outcome would be the same.

33. Type of Sys: OPEN or CLOSED SYSTEMS… Input from outside Open Systems are Self adjusting and self adapting When functioning properly Open Systems reaches into Steady State or equilibrium Entropy All dynamic systems tend to run down over time resulting in entropy or loss of energy Open systems resist entropy by seeking new inputs or modifying the processes to return to a steady state.

34. Type of Sys: OPEN or CLOSED SYSTEMS… Process, Output and Cycles Produce output, operate in cycles, follows continuous processing path Differentiation Have a tendency towards an increasing specialization of functions Equi-finality Implies that, goals are achieved through differing courses of actions and a variety of paths.

35. Type of Sys: OPEN or CLOSED SYSTEMS… Man-Made Information systems Recall definition of information systems.

36. Types of INFORMATION SYSTEMS Types of (Man-made) Information System Formal Information Systems Informal Information Systems Computer-based Information Systems

37. Formal Information Systems… Based on organization based on organization represented by the organization chart This chart is a Map of positions and their authority relationships, indicated by boxes and connected by straight lines. concerned with the pattern of authority, communication and work flow Information is formally disseminated in instructions, memos or reports from top management to the intended users in the organizations Also allows feedback up the chain of command for follow-up.

38. Information Systems in Organizations Organizational charts depict the hierarchy of employees in an organization

39. CATEGORIES OF INFORMATION… STRATEGIC INFORMATION Refers to long range planning policies that are of direct interest to upper management. Information such as trends in financial investment, human resources changes would be of top company officials who are responsible for developing policies and determining long range goals. This type of information is achieved by DECISION SUPPORT SYSTEM (DSS)

40. CATEGORIES OF INFORMATION… MANAGERIAL INFORMATION Of direct use to middle management and department heads for implementation and control E.g. sales analysis, cash flow projections, financial statements This type of information is of use in short and intermediate range planning. Maintained with the aid of Management Information System (MIS)

41. CATEGORIES OF INFORMATION… OPERATIONAL INFORMATION Short term; daily information used to operate departments and enforce day to day rules and regulations of the business. E.g. daily employee absence sheets, overdue purchase orders, current stock available for sale Operational information is established by Data Processing Systems (DPS)

42. MANAGEMENT AND INFORMATION LEVELS… UPPER DSS Decision Support System MIS Management Information System MIDDLE DPS Data Processing System LOWER

43. Informal Information System employee based system designed to meet personal and vocational needs and to help solve work related problems. Knowledge about the inner working of the employee based system is useful during the exploratory face of the analysis. Employee co-operation and participation are crucial in training users. Since computer can’t provide reliable information without user staff support, a proper interface with the informal communication channels could mean the difference the between the success and the failure of the system.

44. Computer Based Information System A third class of the information system realize on the computer for handling the business applications. Transaction processing system (TPS) Management Information System (MIS): Decision Support System (DSS)

45. Management Information System (MIS) The level of the manager in the organization is an important factor in determining the kind of information needed to solve a problem. Lower level management needs detailed internal information to make day to day relatively structured controlled decisions higher level management. For whom the long range objectives are the primary concerns requires summarized information from a variety of sources to attain goals. MIS is a person machine system and a highly integrated grouping of information processing function designed to provide management with a comprehensive picture of specific information of specific operations.

46. Management Information System (MIS) The primary users of MIS are middle and top management, operational managers and support staff. Middle and top management use MIS for preparing forecasts, special request for analysis long range plans and periodic reports. Operational managers use MIS primarily for short range planning and periodic and exception reports. The support staff finds MIS useful for the special analysis of information and reports to help management in planning and control.

47. Decision Support System (DSS) MIS provides limited support to top level management for decision making whereas DSS advances the capabilities of MIS. It assists management in making decisions. Decision support system stands for – Decision emphasizes decision making in problem situation. Support Requires computer added decision situation enough structure to permit computer support. System Combines the integrated nature of problem solving suggesting a combine ‘man’ , machine and decision involvement.

48. Decision Support System (DSS)… DSS results from adding external data sources, accounting and statistical models and interactive query capabilities. The outcone is a system designed to serve all levels of management and top level managements in particular with “what if” unstructured problem situation.

49. Decision Support Systems

51. Gathering information about a problem

52. Calling for a decision

53. Develop alternative Solutions

54. Evaluate Alternative Solutions

55. Actual Selection of a solution for implementationIntelligence Design Choice

56. Expert Systems and Neural Networks Expert systems are designed to analyze data and produce a recommendation, diagnosis, or decision based on a set of facts and rules Knowledge base Inference engine Knowledge engineering Expert system shell Fuzzy logic A neural network uses computer circuitry to simulate the way a brain might process information, learn, and remember

58. Work with internal or external data