For the maintenance problem of intelligent series system with buffer stock, a preventive maintenance model based on the threestage time delay theory is proposed. Firstly, the intelligent series system is decomposed into n − 1 virtual series systems by using approximate decomposition method. The impact factor is introduced to establish the failure rate and maintenance rate model of each virtual machine. Secondly, a preventive maintenance model based on the three-stage time delay theory is proposed for each virtual series system. The machine state from normal operation to failure stage is divided into three steps: initial defect, serious defect, and fault, and different distribution functions are defined in different stages to simulate the degradation process of the machine. Based on the three-stage time delay theory, the machine cost ratio model was established by taking the machine monitoring time and buffer stock as decision variables and the minimum unit time cost rate as objective function. Finally, the rationality and validity of the model are verified by an example analysis, which provides a basis for the maintenance of the intelligent series system.

中文翻译：

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中间缓冲的串联智能系统基于三阶段时延的维修优化新模型

针对带缓冲库存的智能串联系统的维护问题，提出了一种基于三阶段时延理论的预防性维护模型。首先，智能系列系统分解为Ñ − 1个虚拟序列系统，采用近似分解方法。引入影响因素以建立每个虚拟机的故障率和维护率模型。其次，针对每个虚拟系列系统，提出了一种基于三阶段时延理论的预防性维护模型。从正常运行到故障阶段的机器状态分为三个阶段：初始缺陷，严重缺陷和故障，并在不同阶段定义了不同的分布函数，以模拟机器的退化过程。基于三阶段时延理论，以机器监控时间和缓冲库存为决策变量，以最小单位时间成本率为目标函数，建立了机器成本比率模型。最后，