Page 152 - DCAP601_SIMULATION_AND_MODELING

Simulation and Modelling

Notes

At Event 3 there is only one activity, Activity 3-4 in the backward pass, and we find that the value
is 11-7 = 4 weeks. However at Event 2 we have to evaluate 2 activities, 2-3 and 2-4. We find that
the backward pass through 2-4 gives us a value of 11-6 = 5 while 2-3 gives us 4-0 = 4. We take the
smaller value of 4 on the backward pass.

Tabulation & Analysis of Activities

We are now ready to tabulate the diverse events and calculate the Earliest and Latest Start and
Finish times. We are also now ready to compute the SLACK or TOTAL FLOAT, which is defined
as the difference between the Latest Start and Earliest Start.

Event Duration(Weeks) Earliest Earliest Latest Latest Total
Start Finish Start Finish Float

1-2 4 0 4 0 4 0

2-3 0 4 4 4 4 0

3-4 7 4 11 4 11 0

1-3 3 0 3 1 4 1

2-4 6 4 10 5 11 1

1. The Earliest Start is the value in the rectangle near the tail of each activity
2. The Earliest Finish is = Earliest Start + Duration

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