Life cycle cost analysis considering multiple dependent degradation processes and environmental influence

This paper presents a life cycle cost model for systems subject to multiple dependent degradation processes and environmental influence. Different from most existing studies that assume an infinite time horizon for cost analysis, we evaluate the life cycle cost within a finite horizon. The system is subject to multiple degradation processes, among which the dependence is described via copula. In addition to the stochastic dependence of the degradation processes, the health condition of the system is influenced by the operating environment. The environmental influence on the system condition lies in two aspects: It accelerates or decelerates the degradation processes and meanwhile leads to a random failure threshold. System reliability considering multiple dependent degradation processes and environmental influence is assessed as the first step, followed by the life cycle cost analysis. A numerical example is presented to illustrate the proposed model.