基于ExSpect语言的维修过程建模与仿真

Modeling and simulation for repair process based on software ExSpect

研究了单部件可修系统的最优维修更换问题,构建了系统维修更换的Petri网模型,然后利用ExSpect仿真软件进行模拟仿真,从而证明了利用Petri网分析和解决系统维修更换问题的有效性。假定系统每次故障时以概率p进行更换及以概率1-p进行维修,并且每次维修后系统均不能“修复如新”,以系统的故障次数N为策略,利用几何过程建立数学模型,求出最优策略N*,使得系统经长期运行单位时间内期望损失达到最小,并求出系统经长期运行单位时间内期望损失的明显表达式。最后,对所得结果进行了讨论。

Petri net can be conveniently utilized to analyze discrete event systems and to build its model. The optimal repair replacement problem for a repairable system consisting of one component is considered and its Petri net model is built, and then the model is simulated by simulation software ExSpeet so as to testify the effectiveness of Petri net for solving repair replacement problem, Assume that p is the replacement probability and 1 - p is the repair probability while system fails, under the condition that repair after the system failure is not “as good as new”, the number N of failures is taken as policy, the mathematic model is established by using the method of the theory of geometric process, the problem is to determine the optimal policies N^＊ such that the long-run expected cost per unit time is minimized, the explicit expressions of the long-run expected cost per unit time is derived. Finally, the result is discussed also.