基于稳态和非稳态时变可用度模型的适用性

针对METRIC模型中以备件期望短缺数计算的稳态可用度模型能否直接转换适用于非稳态时变可用度模型,扩展METRIC理论,分别建立了仅以备件期望短缺数计算的时变可用度模型和以备件期望短缺数及方差计算的时变可用度模型。在保障系统达到稳态(修复概率为1)和处于非稳态(修复概率小于1)情况下,分别采用2种时变可用度模型计算表决结构单元和串联结构单元的可用度,并与Monte Carlo仿真模型计算得到的结果进行对比分析。结果表明:以备件期望短缺数计算的时变可用度模型仅在串联结构单元且保障系统达到稳态时与仿真可用度值一致,适合于装备全寿命周期内备件配置优化的计算;以备件期望短缺数及方差计算的时变可用度模型无论保障系统处于稳态或非稳态,适应性均较强,适合于任务期作战单元备件配置优化计算。

Applicability of steady-state availability model and unsteady-state time-varying availability model

Aimed at whether the steady-state availability model of METRIC model can be directly applied to the unsteady-state time-varying availability model,by extending the METRIC theory,a time-varying availability model based on the expected order of spare parts and a time-varying availability model based on the expected back order and variance of spare parts have been built.In the case that the system reaches steady state (repair probability is 1) and is in unstable state (repair probability is less than 1),two time-varying availability models are used to calculate the availability of voting structural unit and serial structural unit,and the results are compared with Monte Carlo simulation model.The results show that:when the equipment structure is a series relation and the system is stable,the time-varying availability model based on the expected number of spare parts is consistent with the simulation model,and it is suitable for the calculation of spare parts configuration optimization in the whole life cycle of the equipment;the model of time-varying availability,which is based on the expected order and variance of spare parts,is suitable for the optimization calculation of the spare parts configuration of the combat unit,regardless of the steady state and unsteady state of the support system.