Pertemuan 07 System Development : System Concept

1. Pertemuan 07System Development : System Concept Matakuliah : TI307/Sistem Informasi Tahun : 2012 Versi : 1

2. Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : • Mahasiswa dapat Menerangkan menjelaskan konsep dasar model sistem & pendekatan sistem untuk pemecahan masalah (C2) • Mahasiswa dapat Membandingkan konsep dasar model sistem & pendekatan sistem untuk pemecahan masalah (C4)

3. Outline Materi • Pengertian dan jenis model • Model Sistem Umum • Penggunaan Model Sistem Umum • Elemen Proses Pemecahan Masalah • Struktur Masalah • Pendekatan Sistem • Preparation Effort • Definition Effort • Solution Effort • Review Pendekatan Sistem

4. Introduction • Both managers and systems developers can apply the systems approach when solving problems • The approach consists of three phases of effort: • Preparation consists of viewing the firm as a system, recognizing the environmental system, and identifying the firm’s subsystems • Definition involves proceeding from a system to a subsystem level and analyzing system parts in a certain sequence • Solution involves identifying the alternative solutions, evaluating them, and selecting the best one

5. The Physical System of the Firm Output Resources Transformation Process Input Resources Boundary of the Firm 6-5

6. The Conceptual System • Open-loop systems • Closed-loop systems (feedback loop) • Management control • The information processor 6-6

7. A Closed-Loop System Control Mechanism Feedback Feedback Input Resources Output Resources Transformation Process 6-7

8. The Physical System of the Firm as a Controlled System Management Information Information Input Resources Transformation Process Output Resources 6-8

9. Information is Gathered from All of the Physical System Elements Management Information Information Transformation Process Input Resources Output Resources 6-9

10. The Information Processor Transforms Data into Information Information Information Information Management Processor Data Transformation Process Input Output Resources Resources 6-10

11. Conceptual System (cont.) • Dimensions of Information • Relevancy • Accuracy • Timeliness • Completeness Too Much Information is called ‘Information Overload’ 6-11

12. Standards Measure of acceptable performance Usually stated in specific terms Used to control physical system Consists of: Management Information processor Standards Objectives Overall goal that a system is to obtain Systems have one or more objectives Conceptual System (cont.) 6-12

13. A Comparison of Objectives and Standards Objectives Standards of Performance Satisfy Customer Needs Achieve an annual sales volume of at least $25 million Maintain a 20% share of the market Maintain an annual growth rate of 15% Produce a return on investment for the owners Pay dividends to stockholders each quarter Maintain the price of the firm’s common stock above $85 per share Realize an after-tax profit of 15% of sales Maintain a record of accident-free days Keep employee turnover below 10% Operate efficiently Invest in the future Invest in a minimum of 15% of sales revenue in research and development Achieve stockout on no more than 2% of the items in inventory during the year Keep the number of backorders to less than 5% of all orders processed Have no plant shutdowns due to unavailable materials Develop sources of supply Have no legal actions filed against the firm by customers, suppliers, and the government Operate ethically 6-13

14. Performance Standards are Made Available to Both Management and the Information Processor Standards Information Information Information Processor Management Data Input Resources Transformation Process Output Resources 6-14

15. Conceptual System (cont.) • Management by exception • Compares standards with information output of system • Manager becomes involved when system falls outside range of acceptable performance • Capability provided by CBIS 6-15

16. Conceptual System (cont.) • Critical Success Factors (CSFs) • A CSF is one of the firm’s activities that has a strong influence on the firm’s ability to meet its objectives • Firms have multiple CSFs • CSFs focuses attention on a portion of a firm’s activities 6-16

17. Changes are Made in the Physical System Through the Decision Flow Standards Decisions Information Information Processor Management Data Output Resources Transformation Process Input Resources 6-17

18. Conceptual System (cont.) • Decision Flow • Data is transformed into information by the information processor • Manager transforms information into decisions 6-18

19. The General Systems Model of the Firm Environment Standards Information and Data Decisions Information Information Processor Management Data Physical Resources Physical Resources Output Resources Transformation Process Input Resources 6-19

20. General Systems Model in Context • Helps adjust firm • Provides a sense of stability • Provides mental picture of what to expect 6-20

21. Problems -- Good and Bad • Problem solving • Suppress harmful effects • Capitalize on opportunity for benefit • Decision • The act of selecting a strategy or action 6-21

22. Elements of Problem Solving • Desired state • Current state • Constraints • Internal -- limited resources • Environmental -- pressures to restrict resource flows } Difference = Solution Criterion 6-22

23. Problem Elements of the Problem-Solving Process Elements of the conceptual system Alternate solutions Standards Desired state Problem solver (manager) Current state Constraints Information Solution 6-23

24. Problems versus Symptoms Know the difference • Symptoms are produced by the problem • The problem causes the symptoms • When the problem is corrected the symptoms will cease, but not vice versa 6-24

25. Problem Structure • Structured • Elements and relationships understood • Unstructured • No elements or relationships understood • Semistructured • Some elements understood • DSS concept of managers and the computer working jointly towards a solution 6-25

26. Problem Structure DSS Computer Solve Manager Solve Structured Semi-structured Unstructured 6-26

27. THE SYSTEMS APPROACH • John Dewey identified three series of judgments involved in adequately resolving a controversy • Recognize the controversy • Weigh alternative claims • Form a judgment • During the late 1960s/early 1970s, interest in systematic problem solving strengthened • Management scientists and information specialists produced a recommended framework that became known as the systems approach—a series of problem-solving steps that ensure the problem is first understood, alternative solutions are considered, and the selected solution works (Figure 7.1)

28. Phases and Steps of the Systems Approach Phase I: Preparation Effort Step 1. View the firm as a system Step 2. Recognize the environmental system Step 3. Identify the firm’s subsystems Phase II: Definition Effort Step 4. Proceed from a system to a subsystem level Step 5. Analyze system parts in a certain sequence Phase III: Solution Effort Step 6. Identify the alternative solutions Step 7. Evaluate the alternative solutions Step 8. Select the best solution Step 9. Implement the solution Step 10. Follow up to ensure that the solution is effective Decisions are made at each step of the definition and solution phases 6-28

29. The System’s Approach (cont.) • If a manager can also regard the levels ofmanagement as subsystems, the importance of information flows becomes clear • A problem trigger – a signal that things are going better/worse than planned – usually stimulates a definition effort • A top-down analysis then begins of the system for which the manager is responsible • As the manager studies each system level, the system elements are analyzed in sequence (Figure 7.3)

30. The Systems Approach Requires Decision Making PHASE STEP DECISION Where is the problem? Do new data need to be gathered, or do data already exist? How will data be gathered? What is causing the problem? How many alternatives should be identified? Are these alternatives feasible? Which criteria should be used? How does each alternative measure up to each criterion? Do all criterion have equal weight? Is there enough information to make a selection? Which alternative measures up best to the criteria? When should this solution be implemented? How should the solution be implemented? Who should perform the evaluation? How well is the solution meeting the objectives? 4. Proceed from a system to a subsystem level. 5. Analyze system parts in a certain sequence. 6. Identify alternative solutions. 7. Evaluate the alternative solutions. 8. Select the best solution. 9. Implement the solution. 10. Follow up to ensure that the solution is effective. Definition Effort Solution Effort 6-30

33. Each Part of the System Is Analyzed in Sequence 1. Standards 3. 4. Information processor Management 6. 7. 5. 2. Input resources + Transformation Output Inputs. Outputs resources processes 6-33

34. Steps towards a Solution • Identify Alternative Solutions • Evaluate the Alternative Solutions • Selecting the Best Solution Involves: • Analysis • Judgment • Bargaining • Implement the Solution • Follow Up to Ensure That the Solution Is Effective

35. Definition Effort 4. Proceed from a system to a subsystem level 5. Analyze system parts in a certain sequence An Integrative Model of the Systems Approach Solution Effort 6. Identify alternative solutions 7. Evaluate the alternative solutions 8. Select the best solution 9. Implement the solution 10. Follow-up to ensure solution is effective 6-35

36. Review of Systems Approach • Integrating each step of the systems approach is a managerial challenge • Managerial preparation effort is a good starting point • Next, manager engages in functional decomposition • Definition effort • Finally, manager solves problem • Solution effort 6-36

37. End of Session 7