1. Resource analysis 1 Project management (seminar)

2. Introduction Sometimes one or more resources (especially skilled workers) are equally or more important than time. According to priority, there are: – time-limited and – resource-limited projects. Priority can change over time but it is not wise to have double priorities. Basic tools came from production engineering: loading (resource allocation)

3. Resources Definition: anything that is scarce and required for any activity in the project. Resources are constraints for the project. Resources can be: – Non-storable: has to be renewed for each period e.g. work – Storable: depleted only by usage (remains available if not used) e.g. money The most common resource typology, the 4Ms: – Men – Machines – Money (cost) – Material – Other

4. Loading (resource allocation) The assignment of work to an worker, machine or unit (generally: to a workstation) in time. A workstation can be: – underloaded (load < capacity) – fully loaded (load = capacity) – overloaded (load > capacity) Fully loading is nearly impossible to reach except in flow production. Underloading is the most common, because it respects time. Overloading leads to be late.

5. Defining resources for projects SOW WBS Task list – Resource needs given in resource-hours (e.g. man-hour, machine-hour) – Two forms of resource specification: Rate-constant (can be changed to a constant function/patter): constant usage rate defines the duration, too Total constant: to finish the activity

6. What to do with non-linear duration-resource functions? Use a computer Focus on quasi-linear parts of the functions

7. Capacity Be realistic: – Usual efficiency – Estimated absenteeism, sickness, holidays – Existing commitments – Ancillary tasks and their resource needs – Any additional constraints (like methodology) and limitations (like work contracts) Also calculate with the possibilities (cost, time, trade-offs) to increase capacity

8. Defining resources for projects 2 SOW WBS Task list Logical connections (PNT) Gantt chart and histogram Levelling

9. Using the bar chart Set up and analyse the network – Assign the resource data to the activities Draw the Gantt chart – Aggregate each resource time period by time period throughout the total project Cumulating (Summation or S Curve): Use levelling the load for optimization

10. Network with single resource data START (0) 0 00 0 0 0 0 e (1) 10 130 10 13 3 0 d (2) 2 73 5 10 5 3 c (3) 2 100 2 8 0 b (4) 0 55 5 10 5 5 a (1) 0 20 0 2 2 0 FINISH (0) 13 0 0 0

11. Aggregation with a bar chart (single resource, earliest start) activity12345678910111213 a11 b44444 c33333333 d22222 e111 Res. aggr. 5599955333111 Cum. res. 5101928374247505356575859 Resource units 11 10 9 8 7 6 5 4 3 2 1 123456789 111213 Time

12. Aggregation with a bar chart (single resource, latest start) activity12345678910111213 a11 b44444 c33333333 d22222 e111 Res. aggr. 1133399999111 Cum. res. 1258112029384756575859 Resource units 11 10 9 8 7 6 5 4 3 2 1 123456789 111213 Time

13. The S Curve analysis The minimum slope level is the less ‘critical’ from the viewpoint of availability

14. S Curve of the example

15. Scheduling with constraints Three approaches: Allocation: Activities are scheduled so that an initially defined limit of resources or time is not exceeded. Levelling: A previously generated schedule must be given. Then it levels out the peaks and troughs without changing the TPT. Smoothing: A start time, a TPT and resource priorities.

16. Other possibilities Alternative resources Alternative methods Alternative sequences (if there is no technical dependency)

17. Levelling the load We must have a starting allocation of activities over time and a resource constraint (previous example). Resource units 11 10 9 8 7 6 5 4 3 2 1 123456789 111213 Time Trying to keep the original TPT unchanged means that critical activities should not be moved. Thus try to move activities with free float. Resource units 11 10 9 8 7 6 5 4 3 2 1 123456789 111213 Time

18. Solution There are only 2 activities with free float: b & d Which one to move and to where? Moving activity d 3 days in advance is eliminating the peak. Resource units 11 10 9 8 7 6 5 4 3 2 1 123456789 111213 Time

19. activity12345678910111213 a11 b44444 c33333333 d --- 22222 e111 Res. aggr. 55 777 55 555 111 Cum. res. 5101724313641465156575859

20. S Curve

21. Effect of levelling New „activity”: waiting for the resource (it is a lag, not a true activity) START (0) 0 00 0 0 0 0 e (1) 10 130 10 13 3 0 d (2) 5 100 5 5 0 c (3) 2 100 2 8 0 b (4) 0 50 0 5 5 0 a (1) 0 20 0 2 2 0 FINISH (0) 13 0 0 0 Changes: new precedence relationship, floats, late start and finish times

22. Reading Lockyer – Gordon (2005): Chapter 17

23. Thanks for your attention