Inspection Policies for A System which Is Inoperative During Inspection Periods

Abstract Inspection policy models deal with stochastically failing systems in which failures are detected by inspections only. In this paper we examine a model for a system which is inoperative during the inspection periods. This problem is important in situations where inspections demand a considerable amount of time, such as the inspection of production machines, inspection of communication systems, aircraft maintenance, etc. The costs incurred include the cost of inspections, the cost per time unit of unobserved breakdowns, and the cost of repairing (or replacing) the failed system. The objective is to minimize the expected total cost per time unit. Minimization of the system's unavailability is obtained as a special case by appropriate substitutions.