In this paper, we consider k out of n identical parallel unit systems experiencing deterioration due to random shocks in semi-Markov environments. It is assumed that the occurrence rate of random shocks and the corresponding failures probability are both affected by dynamical environment conditions. We discuss how the semi-Markov environment process can be converted to a Markov process. The systems are maintained through inspections and replacements under some new maintenance policies. The long-run availability and the average cost of the proposed systems are formulated. Finally, we illustrate our results using numerical examples and simulations.

中文翻译：

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在半马尔可夫操作环境中遭受冲击的多单元劣化系统的基于状态的维护策略

在本文中，我们考虑到在n个相同的并行单元系统中，有k个在半马尔可夫环境中由于随机冲击而出现退化。假定随机冲击的发生率和相应的失效概率都受动态环境条件的影响。我们讨论了如何将半马尔可夫环境过程转换为马尔可夫过程。根据某些新的维护策略，通过检查和更换来维护系统。确定了所提议系统的长期可用性和平均成本。最后，我们使用数值示例和仿真来说明我们的结果。