Dong Wenjie, Liu Sifeng, Cao Yingsai, Javed Saad Ahmed
College of Economics and Management, Nanjing University of Aeronautics and Astronautics, Nanjing, PR China.
College of Economics and Management, Nanjing University of Aeronautics and Astronautics, Nanjing, PR China.
ISA Trans. 2021 Jun;112:292-301. doi: 10.1016/j.isatra.2020.12.017. Epub 2020 Dec 10.
This paper is aimed at scheduling optimal preventive replacement policies for a single unit system which is subject to stochastic deterioration and concurrently suffers from external shocks. Different from existing literature, two types of shocks are taken into account according to the effectiveness upon arrival of a random shock, in which Type Ⅰ shock is a non-fatal one increasing the damage magnitude on current degradation amount and Type Ⅱ shock is a fatal one resulting in system catastrophic failure immediately. System survival function is investigated numerically based on the degradation-threshold-shock (DTS) modelling framework, and subsequently, two categories of bivariate maintenance policies are scheduled from different perspectives. The optimal solutions for both policies are derived analytically, and the relative gain on the optimal average maintenance cost rate is incorporated to determine which policy is more profitable. An illustrative example is provided to validate the theoretical results.
本文旨在为一个单一单元系统制定最优预防性更换策略，该系统会遭受随机劣化且同时受到外部冲击。与现有文献不同的是，根据随机冲击到达时的影响效果考虑了两种类型的冲击，其中Ⅰ型冲击是非致命性的，会增加当前劣化量的损伤程度，Ⅱ型冲击是致命性的，会立即导致系统灾难性故障。基于劣化-阈值-冲击（DTS）建模框架对系统生存函数进行了数值研究，随后，从不同角度制定了两类双变量维护策略。通过解析得出了两种策略的最优解，并引入最优平均维护成本率的相对增益来确定哪种策略更具盈利性。提供了一个示例来验证理论结果。
