Preventive repair policy and replacement policy of repairable system taking non-zero preventive repair time *

The repairable system with preventive maintenance is one of the typical systems with wide useful applications in engineering. If the system can be made as good as new by preventive maintenance, both the life stochastic variable of different periods and fault correction time stochastic variable form monotonous stochastic process. Based on the above assumption and the available results, in this paper we discuss the maintenance and replacement policy of the repairable system with preventive maintenance. The intervals of preventive maintenance, T, and the times of system failure, N, are introduced and the vector Markov process method is used. The formulation of steady state average profit rate can be deduced to solve the optimization problem of the maintenance and replacement policy.