Problem 6.5) Use the BOSS computer program to simulate our 322 class. By simulate, I mean how does it behave? Include students arriving at appropriate times, going to a seat, handing in homework, waiting until class is over, leaving, etc. Make sure that they don’t run into each other when going in or out of the door, nor sit in each other’s laps. Make sure none of them get away before being released by the prof at the end of class. 30% of them hand in their homework before sitting down, the rest snag a seat first, then hand in their homework and return to their seat. You can assume that their average interarrival time is 20 seconds and that a total of 35 of the 37 enrolled will show up (an optimistic estimate). Aisles and the area where homework is submitted need not be considered resources due to their ability to concurrently handle multiple entities.
Syntax: ARRIVE, GATE, SETGATE, TESTGATE, GOTO, SEIZE, WAIT, RELEASE. DEPART, IF, RESOURCE, LABELS, RANDOM
No hand solution required.
Address the following question in your homework submission:
Why would the following single statement
IF RANDOM <= 0.3 THEN GOTO takeaseatfirst ELSE GOTO turninhomeworkfirst;
not give the same results as:
IF RANDOM <= 0.3 THEN GOTO takeaseatfirst:
IF RANDOM >= 0.3 THEN GOTO turninhomeworkfirst;
E-mail from a student regarding this problem, and reply:
“There seems to be no data for us to use in our simulations regarding timing of anything.”
I understand your dilemma. Many engineering problems are not well defined and require that you make estimates of the input parameters to solve the problem. This is not something that many of your undergraduate classes require you to do, but it is critical that you start to understand it is a normal part of engineering.
“I know that we can perform simple experiments ourselves to determine how long it takes to open a door, or how long it takes to walk across the room”
Sounds like a reasonable task to me.
“But what about arrival rates, or other distributions?
As mentioned in class, students arrive exponentially distributed.
“Even our experiments will not be accurate, since we can’t actually time all individuals in the class.”
If you feel that you cannot come up with a reasonable estimate for these parameters, you should drop by our classroom and measure the time it takes you to walk from the door to each seat, 200 times. That should give you a reasonable estimate of how long it takes others in the class to perform this action.
“Are we supposed to simply “make” this data up? That doesn’t seem like it would be conducive to a simulation who’s purpose is to mimic reality.” (The word is “whose”, not who’s.)
There is a difference between “making up” something, and generating reasonable engineering estimates. Might as well start learning to do this before you graduate, since you will almost certainly be asked to do so later. It is of course critical that you carefully and conspicuously note all input data for which estimates were made, so that others will know that the accuracy of your solution is based on these assumptions. You should also give your best estimate of how badly you feel the solution will be affected by the assumtions used.