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CHAPTER 8

CHAPTER 8. Basic Information Systems Concepts. SYSTEMS VIEW. FRAMEWORK FOR SEEING INTERRELATIONSHIPS SYSTEM: Set of interrelated components working together to achieve common purpose

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CHAPTER 8

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  1. CHAPTER 8 Basic Information Systems Concepts

  2. SYSTEMS VIEW • FRAMEWORK FOR SEEING INTERRELATIONSHIPS • SYSTEM: Set of interrelated components working together to achieve common purpose • INFORMATION SYSTEM (IS): Collection of information technology, procedures, & people that captures, moves, manages, distributes data & information *

  3. Output 1 Interface COMPONENT 2 Interface Input 2 COMPONENT 2 Interface Input 1 STORAGE 1 COMPONENT 3 SYSTEM BOUNDARY GENERAL STRUCTURE OF SYSTEM ENVIRONMENT

  4. SYSTEM BOUNDARY • DIVIDING LINE • PLACED BASED ON THE PURPOSE: Usually not a fixed line • CONTROL OR REDESIGN WITHIN THE BOUNDARY • ENVIRONMENT OUTSIDE THE BOUNDARY *

  5. SYSTEM BOUNDARY • WHAT CAN BE CONTROLLED: External elements are constraints • WHAT SCOPE MANAGEABLE WITHIN GIVEN TIME PERIOD: Complex systems take longer to design, modify • WHAT IS IMPACT OF BOUNDARY CHANGE: Dynamic changes require accommodation *

  6. COMPONENT DECOMPOSITION • BREAK SYSTEM INTO SUBSYSTEMS • COMPONENTS OF SUBSYSTEM MAY FORM MORE SUBSYSTEMS • OFTEN SUBSYSTEMS ARE EASIER TO UNDERSTAND, CREATE, MODIFY *

  7. GOALS OF HIERARCHICAL DECOMPOSITION 1. COPE WITH COMPLEXITY OF SYSTEM 2. ANALYZE OR CHANGE ONLY PART OF SYSTEM 3. DESIGN, BUILD SUBSYSTEMS AT DIFFERENT TIMES 4. DIRECT ATTENTION OF TARGET AUDIENCE 5. ALLOW COMPONENTS TO OPERATE INDEPENDENTLY *

  8. FUNDAMENTAL COMPONENTS OF ORGANIZATION • PEOPLE • INFORMATION TECHNOLOGY • BUSINESS PROCESSES • ORGANIZATIONAL STRUCTURE EACH IMPACTS THE REST! *

  9. DECISION MAKING PROCESS • INTELLIGENCE: Search for needs, collect data • DESIGN: Generate alternatives, test feasibility • CHOICE: Select from alternatives • PERSUASION: Influencing others to accept & follow chosen solution • IMPLEMENTATION: Install solution on time, within budget • FOLLOW-UP: Monitor, modify, refine CONSTANT FEEDBACK *

  10. BUSINESS PROCESSES A SET OF WORK ACTIVITIES & RESOURCES • IDENTIFY • EVALUATE • REDESIGN USE INFORMATION TECHNOLOGY(IT)TO BREAK RULES! *

  11. EVALUATING A PROCESS X • DOES X DEFINE FIRM TO CUSTOMERS, EMPLOYEES, INVESTORS? • YES: IDENTIFY • NO: GO ON • IS EXCELLING AT X CRITICAL TO BUSINESS? • YES: PRIORITY • NO: GO ON *

  12. EVALUATING A PROCESS X • DOES X SUPPORT OTHER PROCESSES? • YES: BACKGROUND • NO: GO ON • IS X CARRIED OUT ONLY BECAUSE IT IS LEGALLY REQUIRED? • YES: MANDATED • NO: FOLKLORE > ABANDON *

  13. BUSINESS PROCESS REDESIGN* • START WITH “CLEAN SLATE” • USE IT TO RADICALLY CHANGE PROCESSES • QUESTION ASSUMPTIONS & RULES • ASK “WHY?”, “WHAT IF?”, “WHO SAYS SO?”, “WHAT DO CUSTOMERS THINK?” * *Hammer, 1990

  14. USING IT TO BREAK DYSFUNCTIONAL RULES* • OLD RULE: Information can appear in only one place at one time. • DISRUPTIVE TECHNOLOGY: Shared databases • NEW RULE: Information can be used simultaneously in many places * Example #1 *Hammer & Chanmpy, 1993

  15. USING IT TO BREAK DYSFUNCTIONAL RULES* • OLD RULE: Only EXPERTS do complex work. • DISRUPTIVE TECHNOLOGY: Expert systems • NEW RULE: Generalists can do complex work like an EXPERT * Example #2 *Hammer & Chanmpy, 1993

  16. USING IT TO BREAK DYSFUNCTIONAL RULES* • OLD RULE: Field personnel need OFFICES to receive, store, retrieve, and transmit information. • DISRUPTIVE TECHNOLOGY: Portable and home computers, modems, and wireless data communication • NEW RULE: Field personnel send and receive information WHEREVER they are * Example #3 *Hammer & Chanmpy, 1993

  17. PRINCIPLES FOR REDESIGNING PROCESSES* 1. ORGANIZE AROUND OUTCOMES, NOT TASKS 2. ASSIGN USERS OF OUTPUT TO PERFORM PROCESS 3. INTEGRATE INFORMATION PROCESSING INTO WORK THAT PRODUCES INFORMATION * *Hammer, 1990

  18. PRINCIPLES FOR REDESIGNING PROCESSES* 4. CREATE VIRTUAL ENTERPRISE BY TREATING GEOGRAPHICALLY DISTRIBUTED RESOURCES AS THOUGH THEY WERE CENTRALIZED 5. LINK PARALLEL ACTIVITIES INSTEAD OF INTEGRATING THEIR RESULTS * *Hammer, 1990

  19. PRINCIPLES FOR REDESIGNING PROCESSES* 6. HAVE PEOPLE WHO DO WORK MAKE DECISIONS, MONITOR PROCESS BY BUILT-IN CONTROLS * *Hammer, 1990

  20. INFORMATION SYSTEMS LIFE CYCLE • DEFINITION PHASE: End-users & analysts conduct analysis • CONSTRUCTION: Use of structured techniques, system development methodology • IMPLEMENTATION: Plan, test, train, accept, monitor *

  21. ELEMENT SENDING OR RECEIVING DATA. NAMES ARE NOUN LABELS DATA IN MOTION BETWEEN ELEMENTS. NAMES ARE NOUNS OR NUMBERS PROCESSES WITH INPUT & OUTPUT. NAMES ARE VERB PHRASES & NUMBERS DATA STORE WITH INPUT & OUTPUT. NAMES ARE NOUNS & NUMBERS LOGIC TO-BE MODELSYMBOLS *

  22. LOGIC TO-BE MODELPROCESSES • IDENTIFY ENTITIES THAT SUPPLY, USE SYSTEM INFORMATION • DISTINGUISH PROCESSES FROM DATA THEY USE OR PRODUCE • EXPLICATES RULES AFFECTING CHANGING DATA TO INFORMATION • IDENTIFY LOGICAL RELATIONSHIPS • PINPOINT DUPLICATE STORAGE, MOVEMENT OF DATA *

  23. INPUT/OUTPUT PROCESS MAGNETIC TAPE PUNCHED CARD MANUAL OPERATION ON-LINE STORAGE DOCUMENT DATABASE ON-LINE INPUT ON-LINE DISPLAY TELECOMMUNICATIONS LINK WORK PROCESS FLOW SYMBOLS:

  24. BEGIN OR INPUT OR END OUTPUT DIRECTION SUBROUTINE PROCESS MANUAL OPERATION DECISION CONNECTOR PROGRAM FLOWCHART SYMBOLS:

  25. OBJECT-ORIENTED TECHNIQUES • KEY IDEA:Work with reusable objects to speed up development! TWO PRINCIPLES: • ENCAPSULATION: Store data and related operations together within objects • INHERITANCE: Share common characteristics between classes of objects *

  26. OBJECT-ORIENTED APPROACH • DEFINE TASK: Search library of existing objects useful to task • PROCESS: Create bare-bones prototype, test, provide critical feedback, repeat & refine • ELAPSED TIME: Can be weeks *

  27. IT-RELATED RISKS • ORGANIZATIONAL RISKS: From changes in environment • PERSONNEL RISKS: From loss of expertise, system use (or non-use) • SYSTEM PROJECT RISKS: From project management deficiencies • EXTERNAL SECURITY RISKS: Criminal acts, natural disasters *

  28. LIFE CYCLE CONTROLS • DEFINITION & CONSTRUCTION: • Methodology standards • Validation rules & calculations • System testing • IMPLEMENTATION: • Security • Backup & recovery • Auditing Roles *

  29. CHAPTER 8 Basic Information Systems Concepts

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