OPTIMAL PREVENTIVE REPLACEMENT UNDER MINIMAL REPAIR AND RANDOM REPAIR COST.

Investigates the repair/replacement problem for a single unit system with random repair cost. When the unit fails, the repair cost is observed and a decision is made whether to replace the unit or repair it. Although the model in this article is formulated as a model of a single unit system, it can also be used as a suitable representation of a complex, multi-unit repairable system. If only a small part of the system is repaired or replaced upon failure, this would not affect considerably the failure rate and the minimal repair assumption is acceptable. For such systems, the repair cost typically depends on the operating age and may depend also on the number of failures since the last replacement or overhaul of the system.