【生产管理软件Arena】设定系统中实体数量！使用求助！！！急！！！

Fourteen identical machines operate independently in a small shop. Each machine is up (i.e.,works) for between 16 and 24 hours (uniformly distributed) and then breaks down. There arefour repair technicians available. The repair time for repairing a machine follows an exponentialdistribution with a mean of 5.5 hours. Only one technician can be assigned to work on a brokenmachine even if the other technician is idle. If more than four machines are broken down at agiven time, they form a (virtual) FIFO “repair” queue and wait for the first available technician.A technician works on a broken machine until it is fixed, regardless of what else is happening inthe system. All uptimes and downtimes are independent of each other. Starting with all machinesat the beginning of an “up” time, simulate this for 185 hours and observe the time-averagenumber of machines that are down (in repair or in queue for repair), as well as the utilization ofthe repair technicians as a group.

• Think of the machines as “customers” and the repair technicians as “servers”
• There are always the same number of machines floating around in the model
• Machines don’t leave the system until the simulation concludes (time is up)
• At the end of the simulation time, all machines exit the system. Otherwise Arena won’treport critical statistics for the simulation.• Use “Value Added Time” and “Non-Value Added Time” to measure the up-time and downtimeof machines
• Run each simulation for at least 500 trials.
• Do not define the end of the simulation in Run Setup. Once all entities exit the system, thesimulation trial is concluded.
求问这个系统怎么设计？？？怎么能让14个实体在系统里循环然后最后才都出去呢？？？怎么设置结束的条件呢？？紧急求助！！！