Use the Extend model for the two machine parallel system (Two
Machine Parallel.mox) in the Examples/Models and Methods
folder. Use a mean interarrival time of 5 minutes and a mean
service time of 8 minutes for each station. Measure average
number in the queue, average time in the queue and number produced
in a 250 minute period. In parts a through d, use simulation
to estimate the system measures.
a. Use constant service and interarrival times.
b. Use constant service time and exponential interarrival time.
c. Use exponential service time and constant interarrival time.
d. Use exponential service time and exponential interarrival
time.
e. What observation can you make about the effects of statistical
variability on the observed quantities?
f. Use queuing formulas to compute mean number in the queue
and mean time in the queue for exponential service time and
exponential interarrival time. Compare with part d. What observation
can you make about the use of analytic formulas versus simulation
to estimate these quantities?
g. Do part f, but use an average of the results of 10 runs
for simulation estimates.
h. Compare average number in the queue and average time in
the queue with the single channel case with a mean arrival time
of 5 minutes and a mean service time of 4 minutes. We note that
the efficiencies of both the parallel and single channel systems
are the same. Is it better to have two slow machines are one
fast machine?
