Queuing Models in Maintenance Solve the given examples form the application of the two Queuing models in Maintenance: 1. A maintenance department repairs a large number of identical machines. Average time between failures is 3 h and 30 min, and average repair time is 4 h; both are exponentially distributed. The hourly labor cost is $20 per maintenance employee, while the hourly cost of downtime is $30 per waiting machine. Use queuing theory to determine the optimum number of maintenance employees. 2. A manufacturing facility has 25 identical machines. On average, each machine fails every 5 h. For each machine failure, average repair time is 40 min. Both the time between failures and the time for repair are exponentially distributed. The hourly cost for each repair station is $20, while the hourly cost of lost production is $50 per broken machine. Apply queuing theory to determine the optimum number of repairmen for this facility. Queuing Models in Maintenance Solve the given examples form the application of the two Queuing models in Maintenance: 1. A maintenance department repairs a large number of identical machines. Average time between failures is 3 h and 30 min, and average repair time is 4 h; both are exponentially distributed. The hourly labor cost is $20 per maintenance employee, while the hourly cost of downtime is $30 per waiting machine. Use queuing theory to determine the optimum number of maintenance employees. 2. A manufacturing facility has 25 identical machines. On average, each machine fails every 5 h. For each machine failure, average repair time is 40 min. Both the time between failures and the time for repair are exponentially distributed. The hourly cost for each repair station is $20, while the hourly cost of lost production is $50 per broken machine. Apply queuing theory to determine the optimum number of repairmen for this facility