SCHEDULING IN PROJECT MANAGEMENT PROJECT SCHEDULE MANAGEMENT
Download as PPTX, PDF•0 likes•69 views
The document covers project management scheduling, focusing on concepts such as project time planning, critical path method (CPM), and various scheduling techniques including Gantt charts and network diagrams. It emphasizes the importance of defining and sequencing activities, estimating durations, and controlling project schedules while discussing trade-offs in resource allocation and project crashing. Additionally, comparisons between logic-driven and resource-driven scheduling, as well as deterministic and probabilistic scheduling, are explored.
SCHEDULING IN PROJECT MANAGEMENT PROJECT SCHEDULE MANAGEMENT
- 1. Knowledge Areas in Project Management Project Schedule Management Siow May Ling, Ph.D., PMP
- 2. Summary of today’s class Understand the concept of project time planning and scheduling. Compare and contrast logic driven and resource driven scheduling (what is scarce) Draw a network and a Gantt chart to illustrate a simple work package. Understand the concept of Critical Path Method (CPM). Identify the critical activities, critical path and total duration of the network. Calculate the early and late times for each activity. Appreciate the need for rescheduling at different stages of the PLC Apply the concept of Crashing as an example of trade-off analysis
- 3. Project Scheduling 3 • Planning of timetables and establishment of dates of activities • Minimise Risks • To improve efficiency – What are the deadlines? – Who should be doing what and when? – How long will it take? • Provides a basis for monitoring and controlling work & activities
- 4. Project Scheduling Scheduling processes include: • Defining the activities • Sequencing the activities • Calculating the duration of each activity • Allocating resources to each activity • Schedule control Eg: Boiling water 4
- 5. Types of network diagrams • Activity on the Arrow (AOA) 5 • Activity on the Node (AON) Commonly used
- 6. Network Terminology • Activity • an element of the project that requires time. • Serial Activities • are those that flow from one to the next in sequence • Parallel (Concurrent) Activities • activities that can occur independently and, if desired: not at the same time. • Merge Activities: • an activity that has two or more preceding activities on which it depends. • Burst Activities: • are those with two or more immediate predecessors 6
- 7. Activity Relationships 7 Activities in Series Activity A Activity B Activity C Activity A Activity B Activity C Activity D Activities in Parallel
- 8. Network Terminology 8 A B Merge Activities C D A B C D Burst Activities
- 9. Estimating activity durations • Past Experience • Working on similar projects or activities • Comparative projects • Changes is size, scale etc. • Expert Opinion • Specialists • Mathematical Deviations / statistical analysis • PERT 9
- 10. CPM and PERT • PERT is used for projects in which activity times are unknown. For example, take a research and development project (R&D). • CPM is used when the activities are more predictable in time. Example, a construction project.
- 11. Constructing the network diagram 1. Network schedules typically flow from left to right. 2. An activity can not begin until all the preceding connected activities have been complete. 3. Arrows on a network indicate precedence and flow. As a rule, they should not cross over each other. 4. Each activity should have a unique identification number, which should be a larger number that the activities that precede it. 5. Each activity is only considered once within the network. 11
- 12. Constructing a network Activity ID Activity Dependency Duration (Days) A Design Brochure None 2 B Write Copy A 3 C Photo Shoot A 2 D Layout Brochure B,C 2 E Print Brochure D 4 12
- 13. Example Network 13 Activity A Activity B Activity C Activity D Activity E Design Brochure Write Copy Photo Shoot Layout Brochure Print Brochure 2 days 3 days 2 days 2 days 4 days Project Duration 11 days
- 14. The Critical Path Method (CPM) • The Critical Path Method calculates the shortest time a project can be completed by identifying those activities on the critical path. • Earliest start (ES): Earliest time an activity can start • Earliest finish (EF): Earliest time an activity can finish • Duration: The length of time and activity will take • Latest start (LS): Latest time an activity can start in order to meet deadline • Latest finish (LF): Latest time an activity can finish in order to meet deadline • Float: the amount of time an activity can be delayed without affecting the project deadline 14
- 15. Labelling the Node 15 Earliest Start (ES) Earliest Finish (EF) Latest Start (LS) Latest Finish (LF) Float Duration Activity ID
- 16. Creating the network Activity Dependency Duration A - 3 B A 2 C A 3 D C, B 5 E B 7 F E, D 5 16
- 19. Forward Pass Computation • Add activity times along each path in the network (ES + Duration = EF). • Carry the early finish (EF) to the next activity where it becomes its early start (ES) unless… • The next succeeding activity is a merge activity, in which case the largest EF of all preceding activities is selected. 6–19
- 20. Forward Pass 20 A 3 3 0 B 2 5 3 C 3 6 3 D 5 11 6 E 7 12 5 F 5 17 12
- 21. Backward Pass Computation • Subtract activity times along each path in the network (LF - Duration = LS). • Carry the late start (LS) to the next activity where it becomes its late finish (LF) unless • The next succeeding activity is a burst activity, in which case the smallest LF of all preceding activities is selected. 6–21
- 22. The backward pass 22 A 3 3 0 0 0 3 B 2 5 3 3 0 5 C 3 6 3 4 1 7 D 5 11 6 7 1 12 E 7 12 5 5 0 12 F 5 17 12 12 0 17
- 23. Final network 23 A 3 3 0 0 0 3 B 2 5 3 3 0 5 C 3 6 3 4 1 7 D 5 11 6 7 1 12 E 7 12 5 5 0 12 F 5 17 12 12 0 17
- 24. Fully analysed network 0 Start A 3 3 0 0 0 3 B 2 5 3 3 0 5 C 3 6 3 4 1 7 D 5 11 6 7 1 12 E 7 12 5 5 0 12 F 5 17 12 12 0 17 FINISH 0 17 17 17 0 17
- 25. Two activities that have different duration
- 26. EST and EFT 26
- 27. LST and LFT 27
- 28. Project Evaluation and Review Technique (PERT) 28 • Project Evaluation and Review Technique (PERT) • a = optimistic time: – Time required if execution goes extremely well • b = pessimistic time: – Time required if execution goes badly • m = most likely time: – Time required if execution is normal
- 29. PERT Technique 29 Mean duration for each activity = a + 4m + b 6 Mean -1 +1 -2 -3 +2 +3 a b m a b
- 30. Logic Table Activity Depend Optimistic Most likely Pessimistic Mean (d) A - 7 8 9 B A 2 5 8 C A 3 6 9 D C, B 1 2 3 E B 7 8 15 30
- 31. Calculating Mean Times 31 • Estimated time for each activity = (a + 4m + b) 6 • Mean activity A = (7 + (4x8) + 9) /6 = 8 • Mean activity B = (2 + (4x5) + 8) /6 = 5 • Mean activity C = (3 + (4x6) + 9) /6 = 6 • Mean activity D = (1 + (4x2) + 3) /6 = 2 • Mean activity E = (7 + (4x8) + 15) /6 = 9 Total Estimated Project duration = 30 weeks
- 32. Logic Table Activity Depend Optimistic Most likely Pessimistic Mean (d) A - 7 8 9 8 B A 2 5 8 5 C A 3 6 9 6 D B , C 1 2 3 2 E D 7 8 15 9 32
- 33. Fully Analysed Network 33 A 8 8 0 0 0 8 B 5 13 8 9 1 14 C 6 14 8 8 0 14 D 2 16 14 14 0 16 E 9 25 16 16 0 25 Project Critical Path =( A+C+D+E) = 25 weeks
- 34. Gantt Charts • Named after Henry Gantt (1916) • Standard method of presenting schedules Benefits of Gantt charts 1. Easy to create and comprehend 2. Identify the schedule baseline network 3. Allow for updating and control 4. Identify resource needs 5. Easy to create
- 36. Gantt Chart MS Project
- 37. Network to Gantt Chart 37
- 39. Project Rescheduling 39 • Market forces – Earlier completion date • Delayed start date – Fixed completion date • Slippage during execution – Speed up activities • Unable to achieve completion date – Contractual agreement
- 40. Project fast-tracking 40 Activity A Activity D Activity B Activity C Time saved Time Activity A Activity D Activity B Activity C
- 41. Project Crashing • The process of accelerating a project • Involves reducing the time taken to complete an activity • Extending working day (overtime) • Employing additional resources • Making a trade-off between time and cost • Reduce time = increased cost • Limit to available cost • Take a staged approach • Minimum time in which an activity can be done • Minimum crash time 41
- 42. Time/Cost Trade-Off 42 Crash point Normal point Crashed Normal Crashed Normal Duration Cost Reducing Duration increases Cost
- 43. Crash Slope 43 Crash point Normal point Crashed Normal Crashed Normal Crash slope = Crash Cost – Normal Cost Normal Duration – Crash Duration
- 44. Example Activity Dependency Normal Duration (weeks) Normal Cost (RM) Crash Duration (weeks) Crash Cost (RM) A - 2 20 1 60 B A 4 30 1 60 C A 3 10 2 20 D A 2 10 1 40 E B,C,D 3 10 1 20 F E 4 10 3 40 90 44 From the following logic table, reduce the project duration by 4 weeks in the most economical method and determine the project cost after each crash.
- 45. Example • Activity A = (60-20/2-1) = (40/1) = RM40 per week • Activity B = (60-30)/4-1) = (30/3) = RM10 per week • Activity C = (20-10/3-2) = (10/1) = RM10 per week • Activity D = (40-10/2-1) = (30/1) = RM30 per week • Activity E = (20-10/3-1) = (10/2) = RM5 per week • Activity F = (40-10/4-3) = (3/1) = RM30 per week 45
- 46. Example Activity Depend Normal Duration (weeks) Normal Cost (RM) Crash Duration (weeks) Crash Cost (RM) Crash cost per week A - 2 20 1 60 40 B A 4 30 1 60 10 C A 3 10 2 20 10 D A 2 10 1 40 30 E B,C,D 3 10 1 20 5 F E 4 10 3 40 30 90 46 Time allowed for crash
- 47. Network at normal point 47 A 2 2 0 0 0 2 B 4 6 2 2 0 6 C 3 5 2 3 1 6 D 2 4 2 4 2 6 E 3 9 6 6 0 9 F 4 13 9 9 0 13
- 48. Crash E by 2 weeks 48 A 2 2 0 0 0 2 B 4 6 2 2 0 6 C 3 5 2 3 1 6 D 2 4 2 4 2 6 E 1 7 6 6 0 7 F 4 11 7 7 0 11
- 49. Crash B by 1 week 49 A 2 2 0 0 0 2 B 3 5 2 2 0 5 C 3 5 2 2 0 5 D 2 4 2 3 1 5 E 1 6 5 5 0 6 F 4 10 6 6 0 10
- 50. Crash B&C by 1 week 50 A 2 2 0 0 0 2 B 2 4 2 2 0 4 C 2 4 2 2 0 4 D 2 4 2 2 0 4 E 1 5 4 4 0 5 F 4 9 5 5 0 9
- 51. Crash F by 1 week 51 A 2 2 0 0 0 2 B 2 4 2 2 0 4 C 2 4 2 2 0 4 D 2 4 2 2 0 4 E 1 5 4 4 0 5 F 3 8 5 5 0 8
- 53. Summary • Understand the concept of project time planning and scheduling. • Compare and contrast logic driven and resource driven scheduling. • Draw a network and a Gantt chart to illustrate a simple work package. • Understand the concept of Critical Path Method (CPM). • Identify the critical activities, critical path and total duration of the network. • Calculate the early and late times for each activity. • Compare and contrast deterministic and probabilistic scheduling. • Appreciate the need for rescheduling at different stages of the PLC • Apply the concept of Crashing as an example of trade-off analysis • Understand the difference between concurrent engineering and fast track. 53
- 54. References • Gray, C. F. & Larson, E. W. Project Management: The Managerial Process. McGraw-Hill • PMI (2004) A Guide to the Project Management Body of Knowledge (PMBOK), Project Management Institute, Upper Darby, USA. • Pinto, J. (2007) Project Management: Achieving Competitive Advantage. Pearson Education Ltd. • Schwable K (2006) Introduction To Project Management. Thomson • Burke, R. (2006) Project Management - Planning and Control Techniques, (4th Edition) Wiley, Chichester. • www.youtube.com • https://www.flickr.com/photos 54