下面这两个题目做了很久，但感觉结果不对，请高手帮忙根据下面两个题目建模，谢谢！
请发到：ting_season@163.com
再次感谢。
1.
Consider a two-node tandem queueing system shown in the following figure, which has two stages of service.  Suppose there is a total of 11 workers which will be allocated to these two stages. Customers arrive at the first node and leave the system after finishing the services at both stages. The service at each stage is performed by one worker. At least one worker must be allocated to each stage. When multiple workers are available in one stage, the services for multiple customers are performed in parallel and independently, i.e., the service of one customer will not become faster even if there are more workers than customers in a stage. However, customers have to wait if all workers in that stage are all busy. Further, the workers assigned to one stage can not help service at the other stage due to the training and safety requirement. The time to perform the service at stage 1 by one worker is uniformly distributed between 4 to 6 minutes, and the service time at stage 2 is uniformly distributed between 2 and 12 minutes. Customers arrive independently and the interarrival times between two customers are exponentially distributed with a rate of 1 customer per minute. To make customers happy, the manager of this service line wants the total time that a customer spends in the system as short as possible. A design question is how we should we allocate these 11 workers so that the average total time in system (also called system time) is minimized. Denote C1 and C2 as the numbers of workers allocated to nodes 1 and 2. Thus C1 + C2 = 11. We want to find the best alternative of (C1, C2) so that the average system time for the first 200 customers is minimized. Consider the following three alternatives: ·Create an Arena model for this problem. For each alternative design, run your Arena simulation and turn in (only) the page of the report showing the average system time for the first 200 customers. Also please turn in a printout of your Arena model.
2.
You have the distinct honor of demonstrating your ability to multi-task using Arena. You will simulate the simultaneous operation of two separate businesses that have absolutely no interaction. The main focus is on financial concerns, i.e., how much cash input is each business making? You must create animated plots showing this so that one can track the cash input during the one week (24 hours/day) simulation (see italics on this later).
WallySports has the latest fashions from Paris, Los Angeles, and even High Street. You will only do the financials for two of it many fine departments: Clothing and SportsBar+. WallySports is owned by a recent ISE 521 graduate and requires no staff to run it.
Folks just pick whatever clothing they want and you total their sales – no need to worry about how the payment is collected (in reality they just wave their BuckeyeSmarts credit card over the IPC code & the $ are automatically fed to WallySports accounts. In a similar manner, the WishADrink algorithm perfected at the Senior Crawl automatically produces the desired drink when & where needed in the SportsBar+ and $ are automatically transferred from the buyers credit card to WallysSports accounts.
Customers arrive in groups of 2, 3, or 4 (no one comes to WallySports alone) with equal probability. The very 1st group arrives between 0 and 10 minutes after your modeling begins with a flat uniform probability during that 1st 10 minutes. Inter-arrival times are EXPO(3) minutes. Of these customers, 60% pop over to the clothing, buy if desired, and leave WallySports. The rest go to SportsBar+, have some beverages while watching their interpretation of education TV, and then leave WallySports.
No one does both clothes shopping and beverage consumption. The clothing customers are 93.1% female and follow a Normal distribution for purchases with a mean of $185 and a standard deviation of $30.
In the clothing store, 30% of the men buy nothing while the other men in the clothing store follow a Uniform spending pattern between $5 and $55.
Men account for 77% of the SportsBar+ customers and spend Uniformly between $15/hour and $25/hour and stay a Uniformly distributed amount of time between 45 minutes and 3 hours.
Female patron charges are not time linked and follow a Normal distribution with a mean of $20 and a standard deviation of $2.
Show in the animated output on the screen and in the SIMAN output the total spent in the Clothing area, in SportsBar+ and the sum of these two. For the animated output only, show the income in thousands of dollars.
Meanwhile Vanessa and Charlie hope that you will also model their Massage business that is totally separate from WallySports. Customers always arrive in pairs with 50-70 uniformly distributed minutes between the pairs.
The 1st pair immediately arrives at the start of your simulation. It takes two MassageExperts to do one person’s massage at $150 total per massage. The time per massage is Triangular with a min of 45 minutes, most likely value of 1 hour and max of 1 ½ hours. The MassageExperts staffing has 6 folks on the 1st 8 hour shift (when your simulation starts) and then has 4 folks for the next two 8 hour shifts with the same schedule for the whole week. Animate the income both graphically on the screen as well as making sure it makes it into the SIMAN output. As with WallySports, the animated amount must be in thousands of dollars (the SIMAN in just dollars). | 
发表于 2009-9-16 16:38:03
