Optimal maintenance policies for cumulative damage models with random working times

摘要

Purpose - The purpose of this paper is to consider maintenance policies for an operating system which works at random times for jobs. Each job causes some damage to the system and these damages are additive, and the system fails when the total damage has exceeded a failure level K. Design/methodology/approach - Using techniques of cumulative damage models, the maintenance is made at the N-th completion of working time for the first model and at a damage level Z with a limit number of working times N for the second model. Findings ― The system is maintained at the first completion of the working time over time T for the third model. The system fails with probability p(x) when the total damage is x and undergoes minimal repair at failure for the fourth model. The expected cost rates are obtained and optimal maintenance policies are discussed analytically and computed numerically. Originality/value - The paper discusses four maintenance policies for an operating system which works at successive random times for jobs, where the system fails due to damage that can be additive caused by jobs.