本帖最后由 Amethysp 于 2014-12-20 15:06 编辑
1) The ERG in Figure 1 models a system where parts sometimes need to be reworked after they are processed. Assume that: the interarrival times of parts are IID uniformly distributed between 0 and 1 minute, service times of parts at server are IID exponential random variables with mean 0.35 minute, P=0.1 and t_r=10 minutes.
Set RUN(Q,P) Q=0 Developa simulation model in Arena of the ERG in the figure by considering that thequeue can receive 50 parts at maximum. Parts arriving when the queue is full donot enter into the system; remanufactured parts have priority respect to theothers and a dedicated queue. Runthe simulation for exactly 10000 parts for 10 replications using L’Ecuyer’smethod to generate pseudo random numbers for random variables RND and file:///C:/Users/BILLHU~1/AppData/Local/Temp/msohtmlclip1/01/clip_image002.png (see Figure 1) and the Arena random numbergenerator for part processing; use the seeds in the table below. Introducefurther assumptions if needed. Estimatethe expected average delay in queue of a part, the expected time-average numberof parts in queue, the expected utilization and the expected number of partsthat could not enter into the system.
2)A production system is composed of 3 stations. The machines in the stationsprocess parts with the (deterministic) processing times shown in the tablebelow.
One material handling device transports parts between stations with transportation times as in the table below. There is only one transporter device available in the system and the time to load and unload a part is 30 s (for both operations, i.e., loading + unloading).
Piecesarrive stochastically into the system. Interarrival times are iid according toan exponential distribution with mean equal to 4 minutes. Arrived parts may belongto 3 different families (A, B and C according to the mix shown in the tablebelow) and have the following routings: TYPE | | | | | Turning, Milling, Grinding | | | Drilling, Turning, Grinding | | | Milling, Turning, Drilling, Grinding |
Maximum90 parts can stay in the system at the same time. Parts arriving when thesystem is at full capacity are not accepted to enter. |