Unit2 scheduling wbs_network
- 1. Project Organization and Scheduling 1 Project Planning/ Scheduling
- 2. Project Organization and Scheduling 2 Project Scope Planning Scope Management • Ensuring that the project includes all the work required, only the work required. • Dividing the work into major pieces, then subdividing into smaller, more manageable pieces.
- 3. Project Planning – Detailed Plan; Why? This will – Ensure that the appropriate resources will be available precisely when required; – Avoid different activities competing for the same resources at the same time; – produce a detailed schedule showing which staff carry out each activity; – Produce a detailed plan against which actual achievement may be measured; – Produce a timed cash flow forecast; – Re-plan the project during its life to correct drift from the target. Bob Hughes & Mike Cottrerell – Fourth Edition 3
- 4. Project Planning – Scheduling activities Bob Hughes & Mike Cottrerell – Fourth Edition 4 • Feasibility assessment • Resource allocation • Detailed costing • Motivation • Co-ordination Objectives of activity planning
- 5. Project Planning – Defining activities • A project is composed of a number of inter-related activities. • A project may start when at least one of its activities is ready to start. • A project will be completed when all of the activities it encompasses have been completed. • An activity must have a clearly defined start and a clearly defined end-point, normally marked by the production of a tangible deliverable. • An activity requires a resource (as most do) then that resource requirement must be forecastable and is assumed to be required at a constant level throughout the duration of the activity. • The duration of an activity must be forecastable – assuming normal circumstances, and the reasonable availability of resources. • Some activities might require that others are completed before they can begin (these are known as precedence requirements). Bob Hughes and Mike Cotterell – Fourth edition 5
- 6. Project Planning – Identifying activities/ Work Breakdown Structure (WBS) WBS - Identify the main (or high level) tasks required to complete a project and then breaking each of these down into a set of lower level tasks. – Activity based approach – Product based approach – Hybrid approach Advantage – production of a task catalogue that is complete and is composed of non-overlapping activities Note – WBS may not be defined to the finest level initially; however as the project proceeds it can be refined to include finer details. Bob Hughes & Mike Cotterell – Fourth edition 6
- 7. WBS – Activity based Bob Hughes and Mike Cotterell 7
- 8. WBS – Product (deliverable) based Bob Hughes and Mike Cotterell 8
- 9. WBS – Product based (Requirement specifications) Bob Hughes and Mike Cotterell 9
- 10. WBS – Hybrid (activity and product) Bob Hughes and Mike Cotterell 10
- 11. Project Organization and Scheduling 11 WBS - Typical Tasks Detailed WBS Example for procuring an Equipment System
- 12. Project Organization and Scheduling 12 Summary (Top Level) WBS Work Breakdown Structure Summary and Detail tasks, or Parent and Child tasks (Work Package)
- 13. Project Organization and Scheduling 13 Using the Work Breakdown Structure 1. Estimate and schedule the work (Durations, precedences on WBS) 2. Organize and schedule resources (resource allocated WBS) 3. Assign responsibilities – (Resource ramp-up, resource allocated WBS) 4. Estimate and allocate costs and budgets (costed WBS) 5. Add up costs to different levels – Task – Levels on the WBS (phase, account/contract) – Cost account – Total project 6. Get resource commitments 7. Schedule start <--> end dates 8. Track expenditures, schedules and performance Work Breakdown Structure
- 14. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 14 Activity on Node diagram
- 15. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 15 Activity on arrow diagram
- 16. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 16 • A project network should have only one start node • A project network should have only one end node • A node has duration • Links normally have no duration • Precedents are the immediate preceding activities • Time moves from left to right (if there is a possibility of confusion or the direction needs to be reversed, arrows may be used) Contd/- Activity on Node diagram - Rules Code Data take-on Program test Install
- 17. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 17 • A network may not contain loops Activity on Node diagram – Rules (contd/-) Design program Code program Test program Install program Write user manual Code program Test program Release program Correct errors Diagnose errors • A network should not contain dangles Contd/-
- 18. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 18 • Resolving a dangle Activity on Node diagram – Resolving issues Design program Code program Test program Install program Write user manual • Representing lagged activities Sign-off Build prototype Document amendments Test prototype Revise specification 1 2 • Hammock activities – activities with zero duration, start at the start and end at the end of a set of activities; overhead or other resources that are incurred or used at a constant rate.
- 19. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 19 Similar to those for ‘activity on node’ diagrams – A project network may have only one start node – A project network may have only one end node – A link has duration – Nodes have no duration – Time moves from left to right – Nodes are numbered sequentially – A network may not contain loops – A network may not contain dangles Activity on arrow diagram - Rules
- 20. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 20 Activity on arrow diagram - Examples
- 21. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 21 Activity on arrow diagram – Examples of ‘Not allowed’ cases
- 22. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 22 Activity on arrow diagram – Special cases (Dummy activities)
- 23. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 23 Activity on arrow diagram – Special cases (Representing lagged activities)
- 24. Network Diagram Activity label Duration Earliest Start Activity Description Earliest Finish Latest Start Latest Finish Activity Span Float Bob Hughes and Mike Cotterrel - Fourth Edition 24 Labeling Convention (activity on node network)
- 25. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 25 An Example (Table 6.1 from Bob and Mike 4th edition) Activity Activity Duration Precedents label description (weeks) A Hardware selection 6 B Software design 4 C Install hardware 3 A D Code and test software 4 B E File take-on 3 B F Write user manual 10 G User training 3 E, F H Install & test system 2 C, D
- 26. A Hardware selection C Install Hardware B Software design D Code software H Install and test F Use Manual E File take on G User training Start Finish Bob Hughes and Mike Cottrell – Fourth edition Network Diagram (for Table 6.1)
- 27. A 6 Weeks Hardware selection C 3 wks Install Hardware B 4 wks Software design D 4 wks Code software H 2 wks Install and test F 10 wk Use Manual E 3 wks File take on G 3 wks User training Start Finish Bob Hughes and Mike Cottrell – Fourth edition Network Diagram (for Table 6.1)
- 28. A 6 Weeks 0 Hardware selection 6 C 3 wks 6 Install Hardware 9 B 4 wks 0 Software design 4 D 4 wks 4 Code softwar e 8 H 2 wks 9 Install and test 11 F 10 wk 0 Use Manu al 10 E 3 wks 4 File take on 7 G 3 wks 10 User training 13 Start Finish Bob Hughes and Mike Cottrell – Fourth edition Network Diagram (for Table 6.1) Forward Pass
- 29. A 6 Weeks 0 Hardware selection 6 2 8 C 3 wks 6 Install Hardware 9 8 11 B 4 wks 0 Software design 4 3 7 D 4 wks 4 Code software 8 7 11 H 2 wks 9 Install and test 11 11 13 F 10 wk 0 Use Manu al 10 0 10 E 3 wks 4 File take on 7 7 10 G 3 wks 10 User training 13 10 13 Start Finish Bob Hughes and Mike Cottrell – Fourth edition Network Diagram (for Table 6.1) Backward pass
- 30. A 6 Weeks 0 Hardware selection 6 2 8 2 wks C 3 wks 6 Install Hardware 9 8 11 2 wks B 4 wks 0 Software design 4 3 7 3 wks D 4 wks 4 Code software 8 7 11 3 wks H 2 wks 9 Install and test 11 11 13 2 wks F 10 wk 0 Use Manu al 10 0 10 0 wks E 3 wks 4 File take on 7 7 10 3 wks G 3 wks 10 User training 13 10 13 0 wks Start Finish Bob Hughes and Mike Cottrell – Fourth edition Network Diagram (for Table 6.1) Identify critical path and calculate Slack/ float
- 31. A 6 Weeks 0 Hardware selection 6 2 8 8 wks 2 wks C 3 wks 6 Install Hardware 9 8 11 5 wks 2 wks B 4 wks 0 Software design 4 3 7 7 wks 3 wks D 4 wks 4 Code software 8 7 11 7 wks 3 wks H 2 wks 9 Install and test 11 11 13 4 wks 2 wks F 10 wk 0 Use Manu al 10 0 10 10 wks 0 wks E 3 wks 4 File take on 7 7 10 6 wks 3 wks G 3 wks 10 User training 13 10 13 3 wks 0 wks Start Finish Bob Hughes and Mike Cottrell – Fourth edition Network Diagram (for Table 6.1) Calculate activity span
- 32. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 32 Activity Labeling : activity on arrow network Event number Slack/ Float Earliest Start date/ Finish date Latest Start date/ Finish date
- 33. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 33 Network diagram (activity on arrow) for same example – table 6.1
- 34. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 34 Network diagram (activity on arrow) for same example – table 6.1
- 35. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 35 Network diagram (activity on arrow) for same example – table 6.1
- 36. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 36 Network diagram (activity on arrow) for same example – table 6.1
- 37. Network Diagram Bob Hughes and Mike Cotterrel - Fourth Edition 37 Network diagram (activity on arrow) for same example – table 6.1 Critical Path – longest path in the network (Bold line)
- 38. PERT Chart • Unlike the CPM approach, the PERT method does not indicate the earliest date by which we could complete the project but the expected (or most likely) date. An advantage of this approach is that it places an emphasis on the uncertainty of the real world. Rather than being tempted to say ‘the completion date for the project is ….’ we are led to say ‘we expect to complete the project by ….’ • Calculating standard deviation between pessimistic and optimistic for each task, it can be used to rank them according to their degree of risk. Pert Chart 38
- 39. PERT Chart Pert Chart 39
- 40. PERT Chart Pert Chart 40
- 41. PERT Chart Pert Chart 41
- 42. PERT Chart Pert Chart 42
- 43. PERT Chart Pert Chart 43
- 44. PERT Chart Pert Chart 44
- 45. PERT Chart Pert Chart 45
- 46. Module 1 - Introduction 46 If Estimate was Effort, must convert it to Duration Duration = Effort/Resources (sometimes) Taking into account: Resource availability Desire Skill Productivity Scheduling
- 47. Scheduling - Gantt Chart (Bar Chart) Project Organization and Scheduling 47
- 48. Module 1 - Introduction 48 Gantt (Schedule) Drives • Training • Meetings • Reviews • Reports • Site preparation • Delivery dates (date to order) for external items • Payment Scheduling - Gantt Chart
- 49. Module 1 - Introduction 49 Gantt (Schedule) Drives 1. Milestones • Clear, concrete, binary events implying progress • For example: Review (with approval), Sign off of a deliverable, Funds approved • Shown as 0 length task – Try for even frequency • Not too close • Not more than 2 - 3 months apart – Major Point to communicate with • Client • Outside world • Management Scheduling - Gantt Chart
- 50. Module 1 - Introduction 50 Resource Assignment and Cost Planning
- 51. Module 1 - Introduction 51 • Availability • Skills • More experienced people • Less experienced people • Desire • Similar tasks to one person to use learning curve • Assign critical tasks to most reliable people • Tasks that need interaction or are similar • Same person • Two who communicate • Personality and team communication does matter • and again, Availability Assigning Resources
- 52. Module 1 - Introduction 52 Resource Loading and Optimizing Gantt with Resource Histogram
- 53. Module 1 - Introduction 53 Resource leveling - possible rescheduling Gantt with Resource Histogram Manual resource leveling: fast vs good vs cheap Automatic resource leveling: use only as ‘suggestion’
- 54. Module 1 - Introduction 54 Cost Estimating • Similar to Time Estimating (usually done by the same person/group that does the Time Estimates) Calculation of Cost for each WP: Example: If estimate was duration 10 days Assign human resources 2 people Need Effort = Duration x Resources E=2x10=20pd e.g., Resource Cost (RC) = Effort x Rate(includes overhead) RC=20x$1,000=$20,000 (Possible) Plus Fixed Cost (FC) e.g., FC = $5,000 Total cost (TC) = Resource cost + Fixed Cost TC=20,000 + 5,000 = 25,000
- 55. Module 1 - Introduction 55 Costed WBS Use Software to roll costs up the WBS
- 56. Module 1 - Introduction 56 Cost Ramp-Up $100,000.00 $200,000.00 $300,000.00 $400,000.00 Cumulative Cost: Filtered resources Total: CPM Total: Q3 Q4 Q1 Q2 Q3 Q4 Q1 1997 1998 $53,920.00 $127,160.00 $274,360.00 $331,440.00 $349,920.00 $368,400.00 $376,500.00 $376,500.00 Use Software to report cash flow
- 57. Module 1 - Introduction 57 Cost - Sanity checks Cost Estimate Error Range – same as Time Estimate 0 +75% -25% 25 -10 10 -8 Indicative PPA Init Plan Budget EPA Final Plan Definitive PDR Design PPA - Preliminary Project Approval EPA - Effective PDR - Preliminary Design Review
Editor's Notes
- #2: The third knowledge area
- #3: xx
- #27: Prepare the network diagram based on precedents
- #28: Include Duration of activities
- #29: The forward pass Start the independent activities at 0 (Earliest start) Add the duration of activity to calculate ‘Earliest Finish’. Earliest start of dependent activities as earliest finish of precedent activity e.g. earliest start of C will be 6 – the earliest finish of A. Likewise if an activity is dependent on more than one activity, the earliest start will be the earliest finish of the later activity. The project will be complete when all the activities are complete; in this case 13 weeks.
- #30: The backward pass As the name suggests Start from the end and move backwards to initial activities (right to left) Write the latest completion date for last activities (G, H) as project completion date i.e. 13 weeks. Work backwards to calculate latest start date by subtracting duration from latest finish date; This will then automatically become the latest finish date for the previous activity. If two paths meet an earlier activity, the latest finish date which is earlier needs to be selected.
- #31: Identify Critical Path and calculate slack or float Slack/ Float – difference in the earliest start and latest start or latest finish and earliest finish dates Critical path – activities on the path that have zero float activities (Red Color; Start - F – G – Finish)
- #32: Activity Span – Difference between Latest Finish and Earliest Start date.
- #47: Estimating for a project may have given you “direct time” (the number of person days). Need Duration to schedule. Dur = …e.g., 10 person days (pd) of effort may take only 5 calendar days with 2 people doing it. Can’t always divide: if it takes 10 days for one programmer to write a program, 2 may take…11 days! This is due to the communication, management, dividing the work, etc. And how long it takes for a person takes into account all the other factors.
- #48: This is the project from Fig 6 of the text book – explain how to develop using MS Project before getting here.
- #49: Other items that come out of the Gantt. Conclusion: the Gantt is the PM’s most important tool. He/she will be living and breathing Gantts because it can show all time dependencies.
- #50: One of the most important reasons we have a schedule is to know when the milestones occur: - good opportunity to meet & interact with people involved - not too close: usually have a MS meeting, or need to work a bit harder to meet it. - not too far apart because the milestone meeting is a good occasion to see if something is amiss.
- #51: Third knowledge area. Resources are discussed here because 90% of the cost of a professional project (such as an IT project) is resource cost, in other words, people cost.
- #52: Availability is first concern Assign tasks to individuals whose skill level suits the task - do not assign Mickey-mouse tasks to expert - boring - do not assign complex tasks to junior - overwhelming Ask if they wish to do it. Critical task…A reliable person is not necessarily the fastest: it is the one who will do his best to meet the deadline Assign similar tasks to the same person - this will reduce learning time and to minimize people’s interactions Availability: just because someone says ‘I’ll be avail July 1st when my present project is slated to finish - projects have been known to be late. Sometimes you have no choice; you only get the available people.
- #53: Best way to see who is doing what is Resource histogram aligned with Gantt. MS Project can do). Do not explain the overload problem yet…go to next slide, then come back. When back here: Overload is caused by TL working on Architecture as well as prototype in June and July. Ask students for solutions, keeping in mind the balance of Good, Fast, Cheap: 1. Do both half time. Fast. May not be possible 2. Buy another resource: Fast; not Cheap. (look internally before looking externally). Hiring new person sometimes defeats “fast” because you have to train them 3. Do overtime. Fast, not Cheap, not Good 4. Reschedule Architecture to start after Prototype. Delays project by 3 mos. 5. Stop work on prototype in June, do the Architecture, resume Prot. Seems best solution, only delays by 1 month.
- #54: Best way to see who is doing what is Resource histogram aligned with Gantt. MS Project can do). Do not explain the overload problem yet…go to next slide, then come back. When back here: Overload is caused by TL working on Architecture as well as prototype in June and July. Ask students for solutions, keeping in mind the balance of Good, Fast, Cheap: 1. Do both half time. Fast. May not be possible 2. Buy another resource: Fast; not Cheap. (look internally before looking externally). Hiring new person sometimes defeats “fast” because you have to train them 3. Do overtime. Fast, not Cheap, not Good 4. Reschedule Architecture to start after Prototype. Delays project by 3 mos. 5. Stop work on prototype in June, do the Architecture, resume Prot. Seems best solution, only delays by 1 month.
- #55: Estimating Cost, as Time, is at WP (Work package) level Fixed Costs: Material, hardware, capital equipment tools, travel & living, etc.
- #56: The WBS helps you organize cost entry and cost roll up. (Total Cost only). Cost Account here is just a user defined text field.
- #57: Typical cumulative cost graphs. MS Project can do this only for Resource Costs, but can easily export all costs (resource + fixed) to Excel to produce such a graph.
- #58: When was the estimate done? Expected error ranges. Be sure your management is aware.