关键词: 离散事件系统,可诊断性,故障模型,系统评价

Abstract: A quantitative evaluation and analysis method was proposed for partial diagnosable discrete event systems.The proposed method is based on the fault model which is depicted as a tree structure in this paper.Two indicators,diagnosable degree and diagnosable depth,were introduced in the method which can evaluate the diagnosability of systems in cover range and precision respectively.The advantage of the method is that the quantitive values of the evaluating result can be used to analyze and compare different systems which are all partial diagnosable.Furthermore,the impact of different structures of fault model on diagnosable degree and diagnosable depth was discussed and some general principles for constructing fault model were given.The results of analysis and discussion on an example show that the diagnosable degree and diagnosable depth indicators can reflect the diagnosable status of the system accurately when the system is partial diagnosable.The proposed method is useful for designing and analyzing complex systems based on discrete event model and can be helpful for designing and analyzing intelligent systems,self-adaptive systems and self-hea-ling systems.

Key words: Discrete event systems,Diagnosability,Fault model,System evaluation