Analysis of N unreliable work stations in parallel serviced by M repair machines

The authors model the manufacturing system as a finite population M-server queuing system. The case of exponential failure and repair times is considered. The theoretical results are compared with simulations to test accuracy and robustness. The simulations were conducted using three configurations for repair and failure time distributions. The accuracy and robustness of the method are confirmed. The trails show that, when the failure and repair time are equivalent, the number of repair machines needed to ensure reasonably efficient system performance is significantly smaller than the number of workstations and that the marginal increase in efficiency due to adding a repair machine approaches zero