Maintenance optimization of a system subject to two-stage degradation, hard failure, and imperfect repair
针对一个两部件系统，其中一部件的两阶段退化影响另一部件的硬故障概率，研究通过不完美维修和预防性更新来最小化长期成本率的条件维护策略，并给出数值求解方法。
This paper develops a condition-based maintenance (CBM) policy for a two-component system subject to continuous degradation and hard failure. The cumulative degradation of one of the components is modeled by a two-stage degradation process, which then determines the failure probability of the other component via a proportional hazards model. Imperfect repair reduces the degradation level without changing the degradation rate, whereas preventive renewal restores both components to the as-good-as-new condition. The CBM policy is optimized by finding the imperfect repair threshold and the preventive renewal time that minimize the long-run cost rate. We propose a numerical procedure to find the solution without Monte Carlo simulation. Furthermore, the modeling framework is flexible enough to account for maintenance delay and opportunistic maintenance. A case study of the maintenance of a cooling system taken from a company in the process industry is presented to illustrate the applicability of the proposed maintenance policy.