Reliability and maintenance models for a dependent competing-risk system with multiple time-scales

Abstract

In this article, reliability and maintenance models are developed for systems subjected to dependent competing risks and multiple time-scales. Multiple degradation processes and random shocks involve in system failure. The random shocks cause sudden increment jumps in the degradation processes. We use copula method to fit the dependent relationship among various degradation processes. We also study the impact of multiple random usage processes (time-scales) on reliability measures of systems subjected to competing risks. A time-based maintenance policy is proposed to maximize the availability of such systems. The time interval between two successive preventive maintenances and maximum number of preventive maintenances before replacement is found so that the availability of the system is maximized.