Backward Scheduling and Forward Scheduling
Here, you will practice some backward and forward scheduling. Figure 12.7.4.1 presents a simple network, including a legend showing the leadtime elements used.
Solve the forward and backward scheduling problems (calculation of start and completion dates for the order and each operation, as well as the critical path and lead-time margin) listed in Figure 12.7.4.2:
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a. Common forward scheduling.
b. Common backward scheduling.
c. Forward scheduling with different lead-time-stretching factor, that is, a different order urgency, to accelerate or slow down the order.
d. Forward scheduling with lead-time-stretching factor $=0$, which results in the lead time as the sum of operation times plus the technical interoperation times.
Some common problems in the calculation process lead to the following potential errors:
- Calculating incorrect start date and due dates, not respecting interoperation times multiplied by stretching factor
- Multiplying technical waiting time by stretching factor
- Not calculating correctly the longest path in a network
- Not understanding the principle of forward or backward scheduling