Question

You have prepared the following schedule for a project in which the key resource is a backhoe. This schedule is contingent on having four backhoes. You receive a call from your partner, Brooker, who desperately needs one of your backhoes. You tell Brooker you are willing to let him have the backhoe if you are still able to complete your project in 13 months. Develop a resource schedule to see if it is possible to complete the project in 13 months with only three backhoes. The number of backhoes required by each activity is as shown in the diagram. No splitting of activities is possible. K 033 0 1 01110 SIS 0315 0 1 Use the following order of heuristics: 1. Minimum slack, 2. Smallest duration, 3. Lowest identification number

Answer 1

Gantt chart and Resource loading chart based on Early start and early finish times are following:

3 4 5 6 7 8 9 10 11 12 13 14 15 1 1 1 Gantt chart based on Early Start and Finish times ID Resource Duration| ES LF SL 11 2 1 2 3 03 0 2. 2 2 2 1 3 0 3 0 1 1 1 3 1 5 3 9 1 4 1 6 3 9 0 5 2 4 3 9 6 2 9 Resources scheduled 3 3 3 Resources available 3 3 3 1 1 1 1 1 1 1 1 st 2 2 2 N ON 12 4 4 4 3 4 3 2 3 0 1 | 2 3 wNN 2 2 3 WINN 0 3 0 3 3 3 3 Resource Loading Chart 5 NE 3 Resources Scheduled 5 0 1 1 2 3 4 Сл 10 11 12 13 14 15 6 7 8 9 Time Periods

Looking at the resource loading chart, we see that 4 backhoes are scheduled in periods 4 through 7 .

Therefore, based on the early start time schedule, it is not possible to finish the project using 3 backhoes.

We can finish the project using 3 backhoes by rescheduling activity 3 or 5, we reschedule activity 5, because as per minimum slack heuristic, activity 3 must be scheduled before activity 5.

Resulting Gantt chart and resource loading chart is following:

1 3 4 5 6 7 8 9 10 11 12 N 13 14 15 m 2 2 2 1 1 1 1 1 1 Gantt chart - resource constrained ID Resource Duration ESLF SL 1 2 030 2 1 3 03 0 3 1 5 380 4 1 6 3 12 3 2 4 8 12 0 6 2 3 12 15 0 Resources scheduled Resources available 1 1 1 1 1 1 1 1 5 2 2 2 2 2 2 3 3 3 3 3 222 3 3 3 2 2 3 2 3 3 3 3 2 3 2 3 NNlm 2 3 2 3 3 Resource Loading Chart 5 1 2 3 3 Resources Scheduled 4 N 5 6 0 1 3 4 5 6 10 11 12 13 14 15 N 7 8 9 Time Periods

We see that with 3 backhoes, the duration of the project increases to 15 time periods. This is more than permissible duration of 13 time periods (or months) . Therefore, we CANNOT say Yes to to the partner, Brooker.

1)

If only three backhoes are available, then the project will take = 15 time periods

2)

Order in which, activities of the resource-constrained project are scheduled, is following:

First	1
Second	2
Third	3
Fourth	4
Fifth	5
Sixth	6