PROJECT PLANNING AT OUTEL

The Solid State Device (SSD) group at Outel Corporation is charged with the design of a solid state device (the same technology as in a jump drive) to replace a hard drive in a computer.Using an SSD has the advantages of much faster access time and much higher reliability.Recently Outel management has asked the SSD group when the SSD device will be completed.

Five tasks, A, B, C, D and E, must be completed to finish the development of the device.Work on some of these tasks can take place simultaneously, while some tasks must be completed before the work on others can begin.Tasks A, B and C can be started immediately.Task D cannot be started until both tasks B and C are completed.Task E cannot be started until both tasks D and A are completed.The SSD Project can be represented by an Activity-On-Node network, or by an Activity-On-Arrow network (an Arrow Diagram):

The engineers working on each of the tasks are unsure about how long it will take to complete their task.Each task team feels comfortable specifying a triangular probability distribution to represent their task's time to completion.Estimates of the minimum, most likely, and maximum times for completion for the five tasks are:

Task Estimated Time (in Months) to Completion Minimum Most Likely Maximum

A 7 11 16

B 1 2 6

C 4 8 12

D 4 6 11

E 4 6 8

It is worth noting that a triangular probability distribution with minimum value A, most likely value B, and maximum value C, has a mean value equal to (A + B + C)/3.

1. What is the best estimate of when the SSD product will be completed?

1. The SSD device has been promised to an important customer in 21 months.What is the likelihood that this deadline will be met?

1. Eight technicians from Team B have been cross trained to allow them to work for Team C.Each technician transferred from Team B to Team C will increase the three parameters of B's triangular distribution by 0.5 months, but will decrease the three parameters of C's distribution by the same amount.Fractional transfers result in prorated changes.

1. How might Outel arrange the transfers if the goal is to maximize the likelihood that the SSD product will meet the 21-month deadline? Your answer should be to the nearest 0.1.

1. What is the new likelihood that this deadline will be met?

1. (Transfers between Team A and D) Eight technicians from Team D have been crossed trained to allow them to work for Team A. Each technician transferred from Team D to Team A will increase the three parameters of D's triangular distribution by 0.5 months, but will decrease the three parameters of A's distribution by the same amount.Fractional transfers result in prorated changes.Eight technicians from Team A have been crossed trained to allow them to work for Team D. Each technician transferred from Team A to Team D will increase the three parameters of A's triangular distribution by 0.5 months, but will decrease the three parameters of D's distribution by the same amount.Fractional transfers result in prorated changes.(Assume transfers from Team B to Team C are allowed as in question D, and now you can transfer up to 8 technicians from Team A to Team D or reverse as well.)

1. How might Outel arrange the transfers if the goal is to maximize the likelihood that the SSD product will meet the 21-month deadline? Your answer should be to the nearest 0.1.

1. What is the new likelihood that this deadline will be met?