|
|
把同一个系统用不同的软件建模，可以发现很多有趣的地方。/ t2 P- A7 N; M+ W& |! O
这是一个人力资源调度的小模型。/ P' E6 M2 @) P G$ M: I
按题目要求分别用ExtendSim和Arena建模，结果发现离开系统的实体数量有差异3个，参数和时间我已经检查过了，没有差异。已知Arena模型没有错，谁知道ExtendSim输出结果为何会有差别？难道是Shift里面的时间点设置有问题吗？
{& [ [; s5 o) p题目：, i( a- X/ S, i# J1 e+ l- Y5 u
At the DMV photo license center, the current “rule of thumb” is to get the drivers in and . m z: H7 ~8 ]6 q6 P7 R, _
out as fast as possible. Therefore, when drivers come to get their photo ID, the following " G- p& l& |: [5 K2 u J6 X
activities occur: Drivers go to a large counter, pick up a blank form, and fill it out. (We’ll
8 c( g- I" b( |# @5 I! p' nassume the counter is large enough that any number of drivers can obtain and complete 1 v# ?: F/ ^- f5 }* [# {
the form at one time.) The drivers then wait in line for an available photo clerk.
& F7 x- d2 d6 u7 U5 {The drivers are serviced by: 1 part-time clerk (Rich) who works daily from 10 a.m. to 0 l! Y5 x. g% N& m
2 p.m., 1 full-time clerk (Ann) who works daily from 8 a.m. to 5 p.m. with an hour break % `; u) \$ {' K3 [$ X
between 10:30 a.m. and 11:30 a.m., and the site manager (Dina) who only helps when . [( w( v4 Q& r# }* f# F& e
everyone else is busy and there are more drivers to be served. The manager works daily " ]# G, k. t6 p5 t$ ?* s
like Ann, but gets her break from 1:15 p.m. to 2:15 p.m. Due to budgetary constraints, ) v: [# y N2 J2 D7 K' ~( |( `6 h
there are only 2 computers available at the facility. (Don’t worry about using sets for this 6 x$ A# D) b/ e- O8 ~# _
resource.) The computers are used to capture the driver’s signature and to print the
- n- g! K a2 G/ zlicense. / T/ C9 X/ c8 L/ j/ c5 N b% S
The process goes as follows: The clerk reviews the form with each driver, takes the 3 s* p2 u0 f4 Y2 H2 ~2 w- a
driver’s photo, captures the driver’s signature, and prints the completed license. (Note: A
- a+ I( `+ g! J& |. hcomputer is needed for both the signature capture and for printing the license.) The DMV
# f& H* P/ E* ]: c( K! c9 K% `5 Rmanager knows that it normally takes 3 minutes (some as short as 2 minutes, others as
( U1 o/ X: s! [. {+ H; a; U k1 ^long as 4 minutes) to review the form and take a driver’s photo, and anywhere between / D+ c2 s, t, c1 U# M
30 and 60 seconds to capture the driver’s signature electronically. It then takes exactly
" ^0 v! X7 J' f' V* J( n! x45 seconds to print and seal the new photo driver’s license. |
本帖子中包含更多资源
您需要 登录 才可以下载或查看，没有帐号？注册
x
|
发表于 2009-7-5 13:03:33
楼主
