A nonstationary point-process maintenance-model for multi-unit systems

Surveys of preventive maintenance (PM) models for stochastically deteriorating/improving nonrepairable systems have been extensively studied. As yet, this same kind of survey for nonstationary repairable systems has not been performed. This paper discusses a maintenance model for a multi-unit nonstationary repairable system with its components failure pattern modeled as nonstationary stochastic point processes under economic and availability dependency criteria. The methodology is presented and tested with a numerical example. The results obtained show the existence of optimal maintenance actions in which both costs and benefits (availability) can be quantified and where an optimum balance between both is obtained