Reliability modeling for competing failure systems with instant-shift hard failure threshold

Abstract

Many researchers have modeled systems under multiple dependent competing failure processes (MDCFP) in recent years. Typically, those failure processes consist of degradation (soft failure) and random shock (hard failure). In previous papers the threshold of hard failure has been a fixed value, which does not reflect engineering practices. Threshold refers to the ability to resist external random shocks, which shifts with time as the system is used. Thus, this paper establishes a model for MDCFP with instant-shift hard threshold. The hard failure threshold changes with time instantaneously, and it is also influenced by external shocks. This paper also presents a system reliability model. The effectiveness of the presented model is demonstrated by a reliability analysis of the micro-engine at Sandia National Laboratories. In addition, a sensitivity analysis is performed for specific parameters.

Constructing copulas from shock models with imprecise distributions

“…The first ones of the kind seem to have been introduced in 2016 [49] followed by [18,31,32,33]. It is perhaps somewhat surprising that the first citations in engineering papers of this kind of copulas appeared only two years after the first appearance of the model itself [35,36].…”

Reliability and maintenance modeling for competing failures with intermission considered

“…An and Sun 13 built the competing failure model with shock process and multi-degradation process and the dependence among those failures are modeled by Copula function. Liu et al 14 considered the instant-shifting threshold of hard failure and established a competing failure model. Beyond the theoretical models, there are also many researches about the competing failures in engineering practice.…”