1. RESOURCES Roger D. H. Warburton © Kanabar / Warburton, 2009 1

2. Objectives 2  Understand Constraints  Resource Constraints  Leveling

3. S CHEDULES & C OST E STIMATES Project network times are not a schedule until resources have been assigned Cost Estimates are not a budget until they have been time phased 3

4. R ESOURCES AND P RIORITIES The Project network is not a schedule until resources are assigned Assumption: Resources will be available in the required amounts when needed Assigning resources requires making realistic judgments of availability and project durations 4

5. R ESOURCE C ONSTRAINT E XAMPLE Plan Play Hire Actors Select Theater Hire Musicians Plan Play Hire Actors Select Theater Hire Musicians Rehearse Re- hearse 5

6. T YPES OF P ROJECT C ONSTRAINTS Technical (Logical) Constraints Constraints related to the network sequence in which project activities must occur Network Diagram Physical Constraints Activities that cannot occur in parallel or are affected by contractual or environmental conditions Resource Constraints The absence, shortage, or unique interrelationship and interaction characteristics of resources that require a particular sequencing of project activities. 6

7. C ONSTRAINT E XAMPLE Resource Dependency takes precedence over the technological dependency Does not violate the technical dependency Plan Play Hire Actors Select Theater Hire Musicians Re- hearse 7

8. R ESOURCE Q UESTIONS Will assigned labor be adequate? Will assigned equipment be adequate? Will outside contractors be needed? Do unforeseen dependencies exist? Is there flexibility in using resources? Is the deadline still realistic? 8

9. T YPES OF R ESOURCE C ONSTRAINTS People designer, engineer, welder, painter Materials concrete, survey data, deliveries in winter night road work Equipment Earth moving equipment, copiers Working Capital 9

10. C LASSIFICATION OF S CHEDULING P ROBLEMS Time Constrained A project that must be completed by an imposed date Resource Constrained A project in which the level of resources available cannot be exceeded 10

11. R ESOURCE P ROBLEMS Are very complex even for small networks 11

12. H ELP ON S CHEDULING P ROBLEMS The priority matrix helps determine if the project is time or resource constrained. TimePerformanceCost Constrain O Enhance O Accept O 12

13. C RITICAL R ESOURCE Q UESTION If the CP is delayed, will resources be added to get the project back on schedule? “Yes”Time Constrained “No”Resource Constrained TimePerformanceCost Constrain O Enhance O Accept O 13

14. T IME C ONSTRAINED P ROJECT A project that must be completed by an imposed date. Project Duration is fixed Resources are flexible Resources can be added to ensure schedule is met 14

15. R ESOURCE C ONSTRAINED P ROJECT A project in which the level of resources available cannot be exceeded Resources are fixed Time is flexible If the resources are inadequate, it is acceptable to delay the project 15

16. C ONSTRAINED P ROJECTS All projects are constrained Something will have to give What are the priorities? Negotiation is key 16

17. L IMITING A SSUMPTIONS Splitting activities is not allowed Once an activity is started, it is carried to completion Activities may not be started and stopped Resources on an activity cannot be changed Activities with the most slack pose the least risk Reduction of flexibility does not increase risk The nature of an activity (easy, complex) doesn’t increase risk 17

18. E XAMPLE OF T IME C ONSTRAINED B OTANICAL G ARDEN FIGURE 8.2 One resource: backhoes Interchangeable Slack 18

19. B OTANICAL G ARDEN ( CONT ’ D ) FIGURE 8.2 (cont’d) 19

20. T IME C ONSTRAINED P ROJECT A project that must be completed by an imposed date. Project Duration is fixed Resources are flexible Resources can be added to ensure schedule is met Smooth the Resources Focus on Resource Utilization Erratic resources are difficult to manage Level the resources Delay non-criticals Use positive slack to reduce peak demand 20

21. B OTANICAL G ARDEN ( CONT ’ D ) FIGURE 8.2 (cont’d) 21

22. B OTANICAL P ROJECT Activities with slack: Irrigation, Fence & Walls Delay Fence & Walls – Smoother Peak demand reduced Resources reduced from 4 to 3 Smoother profile, easier to manage Cost to move (people or machines) Loss of flexibility Reduced slack, critical activities Most slack = least risk 22

23. E XAMPLE OF T IME C ONSTRAINED B OTANICAL G ARDEN FIGURE 8.2 One resource: backhoes Interchangeable Slack 23

24. R ESOURCE -C ONSTRAINED P ROJECTS Projects that involve resources that are limited in quantity or by their availability. Scheduling of activities requires the use of heuristics (rules-of-thumb) A modest network with a few resources has thousands of feasible solutions 24

25. R ESOURCE A LLOCATION M ETHODS FOR R ESOURCE -C ONSTRAINED P ROJECTS Scheduling of activities requires the use of heuristics (rules-of-thumb) that focus on: 1. Minimum slack 2. Smallest (least) duration 3. Lowest activity identification number The parallel method is the most widely used heuristic An iterative process that starts at the first time period of the project and schedules period-by-period any activities scheduled to start using the three priority rules. 25

26. S PLITTING /M ULTITASKING Scheduling technique used to get a better schedule and/or increase resource utilization Interrupting work on an activity to employ the resource on another activity, then returning the resource to finish the interrupted work. Feasible when startup and shutdown costs are low. Considered a major reason why projects fail to meet schedule. 26

27. T HE I MPACTS OF R ESOURCE -C ONSTRAINED S CHEDULING Reduces delay but reduces flexibility. Increases criticality of events Increases scheduling complexity May make traditional critical path no longer meaningful Can break sequence of events May cause parallel activities to become sequential and critical activities with slack to become noncritical 27

28. C OMPUTER D EMONSTRATION OF R ESOURCE -C ONSTRAINED S CHEDULING 28

29. L EVELING Within Slack Outside Slack Complicated – no simple solution Destroys the network! Now what? 29

30. S UMMARY : L EVELING How do we Level? After you gather your resource requirements: Identify resource peaks Delay non-critical tasks with float Extend schedule if needed 30 In conclusion: Resource requirements and availability impact your schedule. You must leverage your skills and tools.

31. W ORKSHOP Work on the Resource Requirements Associated with the Case Study 31

32. S CHEDULE C OMPRESSION 32

33. O BJECTIVE Understand schedule compression techniques Understand fast tracking and crashing concepts within this context. 33

34. W HAT IS D URATION C OMPRESSION Duration compression is a special case of mathematical analysis that looks for ways to shorten the project schedule without changing the project scope. PMBOK® Guide 4 th Edition 34

35. W HY C OMPRESSION ? Schedule does not meet planned milestone dates. Schedule estimate is longer than what the sponsor desires. Applying resource loading and leveling impacts schedule. Schedule slip occurs during project execution due to things like scope creep or other circumstances. Renegotiated project completion date 35

36. H OW ? Utilize resources, duration, scope and additional assets. Use techniques such as fast tracking and crashing. 36

37. F AST T RACKING Overlap activities. 37 A B – 3d What are the Risks?

38. C RASHING Apply additional resources to critical path Often results in greater project costs Look for least expensive reduction in time 38

39. D ISCUSSION From your experience what additional skills and assets are available for schedule compression? 39

40. R EFERENCES Kanabar & Warburton: MBA Fundamentals, Kaplan Publishing, 2008 Gray & Larson: Project Management – The Managerial Process, McGraw-Hill, 2008. PMBOK: Project Management Institute, 2008 40