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Management Information Systems

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  1. Management Information Systems Chapter 10 Information Systems Development

  2. This Could Happen to You • Dee wanted to develop a blog for communication • Focused goal • Short time frame • Was successful because system was simple • Single contributor • No user training • RFID at DSI more sophisticated • Vendors would need to place RFID chips • Computer program would be needed to process data

  3. Study Questions • Q1. What is systems development? • Q2. Why is systems development difficult and risky? • Q3. What are the five phases of the systems development life cycle? • Q4. How is systems definition accomplished? • Q5. What is the user’s role in the requirements phase? • Q6. How are the five components designed? • Q7. How is an information system implemented? • Q8. What are the tasks for systems maintenance? • Q9. What are the problems with SDLC?

  4. Q1. Systems Development • Systems analysis and design • Process of creating and maintaining information systems • Development involves all five components • Requires more than programming or technical expertise • Human relation skills • Business knowledge • Understanding of group dynamics • Information systems are never off-the-shelf • Must be adapted to fit needs of business and people

  5. 系統開發與軟體開發的比較

  6. MIS in Use: Thinking Big about Systems Development • Large scale corporate information systems are more complex • Need to ensure all employees are working toward same goals • Must develop system that will function consistently in different languages • May need to store information on worldwide use of product and the relevant laws • Most information systems are process-design oriented • Must be carefully planned and executed

  7. Q2. Major Development Challenges • Difficulty of determining requirements • Requirements change as system develops • Scheduling and budgeting difficult to estimate • Change as scope changes • Technology changes • Diseconomies of scale • Brook’s Law

  8. Q3. Systems Development Processes • Methodologies: • Systems development life cycle (SDLC) • Rapid application development (RAD) • Object-oriented systems development (OOD) • Extreme programming (XP) • No single process works in all situations • Different requirements • Some systems wholly automated, others not • Use augmentation system to fill gaps

  9. SDLC • Classical process with five phases: • Systems definition • Management’s statement defines new system • Requirements analysis • Identify features and functions • Component design • Based on approved user requirements • Implementation • Implement, test, and install new system • System maintenance • Repair, add new features, maintain

  10. Phases in SDLC

  11. Q4. Systems Definition (1) • Define goals and purpose for new system • Must facilitate organization’s competitive strategy • Supports business processes • Improves decision making • Determine project’s scope • May be delineated by users, processes, or facilities • Assess feasibility of project • Cost • Schedule • Technical feasibility • Organizational feasibility

  12. SDLC:系統定位階段

  13. Systems Definition (2) • If deemed feasible, project team created from IT personnel and users • Managers • Systems analysts • Programmers and software testers • Users

  14. Ethics Guide: Estimation Ethics • Buy-ins • Companies agree to produce products for less than it knows will be required • “Time and materials” contracts • Fixed-cost contracts • In-house projects are often started with buy-ins • Projects started with hopes of more money later • Team members may disagree about costs • Not all costs may have been included in estimate • Also may have buy-in on schedule

  15. Q5. Requirements Analysis Phase • Determine and document features and functions • Interview users • Document requirements • Examine existing system • Review reports, forms, queries, application features • Security and controls • Approve requirements • Less expensive to change system in this phase

  16. SDLC:需求分析階段

  17. Q6. Designing Components • Develop and evaluate alternatives • Accurate requirements critical • Hardware design determined by project team • Software design depends on source • Off-the-shelf • Off-the-shelf with alterations • Custom-developed programs • Data model converted to database design • Procedures designed for BI system • Job descriptions created for users and operations personnel

  18. SDLC:元件設計階段

  19. 設計的程序、步驟

  20. Q7. Information System Implementation • System must be built • Components constructed independently • Document and review • System testing • Individual components tested • System integrated and tested • Users must be converted to new system

  21. SDLC:實作階段

  22. Systems Testing • Test plan • Sequences of actions that users take when employing system • Both normal and incorrect actions should be considered • Labor intensive • Product quality assurance (PQA) • Testing specialists • Beta testing • Future system users try out system on their own

  23. System Conversion (1) • Converting business activity from old system to new • Pilot installation • Organization implements entire system on single, limited unit • If systems fails, it only affects limited boundary • Reduces exposure • Phased installation • New system installed in phases • Tested after each phase • Continues until installed at entire organization • Can’t be used in tightly integrated systems

  24. System Conversion (2) • Parallel installation • New system runs in parallel with old system during testing • Expensive and time consuming • Data must be entered twice • Provides easy fallback position • Plunge installation • Direct installation • Install new system and discontinue old • There is no backup position

  25. 五元件的設計與實作

  26. Q8. Systems Maintenance • Fixing or adapting system • Need method to track system failures and enhancements • Corrections usually prioritized based on severity • Enhancements usually prioritized based on business decision • Must generate reasonable rate of return • Decision to restart systems development process

  27. SDLC:系統維護階段

  28. Q9. Problems With SDLC • SDLC waterfall • Phases are not supposed to be repeated • Often teams have need to repeat requirements and/or design phases • Difficulty in documenting requirements • Analysis paralysis or uncertain requirements • Scheduling and budget difficulties • Multiyear projects difficult to properly schedule • Estimations on labor often produce insufficient budgets

  29. Guide: The Real Estimation Process • Estimating is just theory • Project managers sum up estimates and take to management • Management then negotiates the schedule and budget • Every change will negatively impact the project • Start with optimistic schedules and end up with late projects

  30. How Does the Knowledge from This Chapter Help You at DSI? • You can now give a summary of the phases of SDLC • Describe tasks more specifically • Create a realistic schedule