The queuing time and the production capabilities for
each worker-product combination are provided in Table
III and Table IV, respectively. Depending on the operator
assigned to a workstation building product A, the rework
rate may vary from 0.1 to 0.3. For each of these cases, the
processing time remains 4 minutes with standard
deviation 2 minutes. Machine availability is not
considered in this case, so A is held at 1 for complete
availability. Repair time SCV is held constant at 1 in all
cases to simplify interpretation of the results. Depending
on the chosen value for p, the arrival rate is then set to
allow 80% station utilization with SCV of arrivals equal
to 1. Finally queuing time is found using (1). The number
of parts produced in 8 hours is simply the arrival rate
multiplied by time, since arrival rate is always kept below
maximum throughput rate. For product A at p equal to 0.1,
the arrival rate is set to .18 parts per minute (10.9 parts
per hour). In 8 hours, 87.3 parts are produced. Tables III
and IV feed the optimization model that was set up and
solved using ILOG OPL Development Studio, with
results presented in the following section.