Performance Sensitivity Analysis for Machine Repair Problem with Two Failure Modes and Working Vacation

Production equipment is crucial to efficiency enhancement and product quality in the manufacturing industry. Repairman and removable standbys can be configured to support continuous production in order to minimize downtime and capacity loss associated with the malfunctioning of manufacturing equipment. Under these conditions, an idle repairman temporarily leaving the system to perform other tasks can undermine service performance. This paper presents a limited-capacity machine repair problem with standbys, two failure modes, and a working vacation policy. The steady-state system-size distribution is derived via the matrix analysis method and matrix decomposition. Based on steady-state probabilities, we derived closed-form formulations of several critical metrics for the assessment of system characteristics. Sensitivity analysis is performed to illustrate the effects of uncertainty in system parameters. Management implications are also addressed.