Presentation Transcript

1. Project Scheduling (1)

   Tran Van HoaiFaculty of Computer Science & Engineering HCMC University of Technology Tran Van Hoai
2. What is project management? Project management (PM) is the discipline of planning, organizing, securing and managingresources to bring about the successful completion of specific engineering project goals and objectives Project is not business as usual (operations) Operations means repetitive, permanent, semi-permanent Tran Van Hoai
3. Primary challenges of PM To achieve all of the predefined project goals To honor the preconceived project constraints Typical constraints are scope, time, and budget Tran Van Hoai
4. Brief history (1) 1900: PM has been practiced in civil engineering projects 1910: Gantt chart, proposed by Henry Gantt 1916: 5 management functions, proposed by Henri Fayol <1950s: PM performed by Gantt charts, and informal techniques and tools Tran Van Hoai
5. Brief history (2) 1950: mathematical project scheduling models developed Critical Path Method (CPM) Program Evaluation and Review Technique (PERT) Technology developed Certification Standard Organizations … Tran Van Hoai
6. Approaches (1) Traditional approach Waterfall model in SoftwareDevelopment Tran Van Hoai
7. Approaches (2) Critical Chain Project Management (CCPM) More emphasis on resources Based on Theory of Constraints (Goldratt [1984]) Guarantee that resources are ready when critical chain tasks must start Extreme Project Management (XPM) PERT-based models do not work well for multi-project company environment to manage very complex and very uncertain projects “lightweight” models, human interaction management Tran Van Hoai
8. Approaches (3) Event chain methodology Complement CPM and CCPM methodologies identify and manage events and event chains to cope with uncertainty PRINCE2 Structured approach Automatic control Tran Van Hoai
9. Approaches (4) Process-based management Maturity models: CMMI (Capability Maturity Model Integration) Tran Van Hoai
10. Processes (stages) Initiation Planning or development Production or execution Monitoring and controlling Closing In R&D projects (much explorative elements), these stages may be supplemented with decision points Tran Van Hoai
11. Initiation (1) To determine the nature and scope of the project Must be performed well Tran Van Hoai
12. Plan for initiation Analyzing the business needs/requirements in measurable goals Reviewing of the current operations Financial analysis of the costs and benefits including a budget Stakeholder analysis, including users, and support personnel for the project Project charter including costs, tasks, deliverables, and schedule Tran Van Hoai
13. Planning & Designing To plan time, cost and resources adequately to estimate the work needed and to effectively manage risk during project execution determining how to plan (e.g. by level of detail or rolling wave) developing the scope statement selecting the planning team identifying deliverables and creating the work breakdown structure identifying the activities needed to complete those deliverables and networking the activities in their logical sequence estimating the resource requirements for the activities estimating time and cost for activities developing the schedule developing the budget risk planning gaining formal approval to begin work Tran Van Hoai
14. Scheduling Define work activities Sequence work activities Schedule activities Identify work activity resource Estimate work activity duration Tran Van Hoai
15. Executing To complete the work defined in the project management plan to accomplish the project's requirements Tran Van Hoai
16. Monitoring & Controlling To observe project execution so that potential problems can be identified in a timely manner and corrective action can be taken, when necessary, to control the execution of the project Tran Van Hoai
17. Closing formal acceptance of the project to archive of the files and to document lessons learned Tran Van Hoai
18. Project scheduling - definition Project = Collection of tasks (activities) A task requires other tasks accomplished before it starts (precedence relations) Factors affecting completion time Resources Detail level of the project target Tran Van Hoai
19. Objectives Determining a schedule leading to earliest completion time for entire project Calculate the likelihood a project completed within a certain time period Finding minimum cost to finish the project by a certain date Finding a schedule smoothing out resource allocation … Tran Van Hoai
20. Klonepalm 2000 activity description Tran Van Hoai
21. Precedence relations Tran Van Hoai
22. PERT/CPM network Network representation reflecting precedence relations Network G = (V,A) V: vertex set = set of activities, vi = estimated completion time A: arc set = set of precedence relations aij if activity j is preceded by activity i Tran Van Hoai
23. Klonepalm 2000 PERT/CPM network E 21 B 15 C 5 A 90 F 25 G 14 D 20 H 28 I 30 J 45 Tran Van Hoai
24. PERT/CPM approach PERT/CPM analyses are To determine minimal possible completion time To determine a range of start and finish times for each activity (such that project completed in minimal time) Earliest times (ES,EF) Computed by forward pass Latest times (LS,LF) Computed by backward pass Tran Van Hoai
25. Earliest/Latest Start/Finish Times EF(X) = ES(X) + Weight(X) LF(X) = LS(X) + Weight(X) ES(X) = MAXY=immediate predecessor of X{EF(Y)} EF(A) LF(A) ES(A) LS(A) Tran Van Hoai
26. ES/EF Sequence 149,170 90,105 105,110 E 21 B 15 C 5 129,149 90,115 149,177 0,90 115,129 A 90 F 25 G 14 D 20 H 28 (Minimal) Estimated completion time = 194 90,120 149,194 I 30 J 45 Tran Van Hoai
27. LS/LF Sequence 149,170 90,105 105,110 E 21 B 15 C 5 173,194 95,110 110,115 90,115 129,149 149,177 0,90 115,129 A 90 F 25 G 14 D 20 H 28 166,194 90,115 115,129 0,90 129,149 90,120 149,194 I 30 J 45 119,149 149,194 Tran Van Hoai
28. Slack times To measure the amount of time an activity can be delayed from its ES without delaying the project’s estimated completion time Slack(X) = LS(X) – ES(X) Critical path are those with slack time = 0 Tran Van Hoai
29. Critical path 149,170 90,105 105,110 E 21 B 15 C 5 173,194 95,110 110,115 90,115 129,149 149,177 0,90 115,129 A 90 F 25 G 14 D 20 H 28 166,194 Critical path = longest path 90,115 115,129 0,90 129,149 90,120 149,194 I 30 J 45 119,149 149,194 Tran Van Hoai
30. Analyses of possible delays What if an activity on critical path is delayed ? What if an activity not on critical path is delayed ? What if multiple delays occur ? Tran Van Hoai