模糊灰色聚类和组合赋权法在铁路信号系统可靠性评估中的应用

Application of the reliability assessment method to the railway signal system based on the fuzzy gray clustering and synthetic weighing approach

针对模糊综合评判法在进行列车运行控制系统可靠性评估时的不足,提出基于模糊灰色聚类和组合赋权法的可靠性评估方法,以更客观地评估铁路信号系统的可靠性,降低评估结果的不准确性和不可靠性。首先,利用组合赋权法分别计算CTCS-3级列车运行控制系统各子系统基本单元的权重。然后,采用灰色聚类法评估列车运行控制系统各子系统的可靠性。最后,在对列车运行控制系统子系统可靠性评估结果的基础上,结合各子系统权重值,利用模糊综合评判方法,评估整个列车运行控制系统的可靠性。结果表明,基于模糊灰色聚类和组合赋权法的可靠性评估方法能够实现CTCS-3级列车运行控制系统可靠性评估,评估结果符合实际情况。

This paper aims to introduce a reliability assessment method based on the fuzzy gray clustering and combination weighing approach to evaluating the railway signal system working status-quo-in-situ.For the time being,most of the currently adopted assessment methods in assessing the system reliability are mainly dependent on the expert scoring policy with all the weighing of evaluation indexes given by the experts.In such a case,it is quite difficult to exclude the effects of unavoidable subjective factors on the evaluation results.Therefore,the paper would like to propose a more comprehensive more reliable assessment approach based on the fuzzy gray clustering and synthetic weighing measures for assessing the Chinese train control system at level 3（CTCS-3）.For this purpose,first of all,we have set up an assessment system based on the fuzzy gray clustering theory,including the index set and evaluation criteria,and,then,we have adopted the hierarchical analysis process（AHP） and entropy weighing method to work out a weighing system for the evaluation indexes of each subsystem,correspondingly,so as to determine the general weighing situation with the synthetic weighing method.Secondly,the reliability status-in-situ of each subsystem should be evaluated with the gray clustering method in hoping to get the clustering coefficients of the subsystems and establish a fuzzy comprehensive evaluation matrix.And,last of all,it is necessary to join the fuzzy comprehensive evaluation matrix and the general weight system of CTCS-3 together in favor of the use of the fuzzy comprehensive evaluation methods to increase the reliability of CTCS-3.Thus,the assessment results we have gained show that the reliability of CTCS-3 is high,with the subjective weighing results done by the experts amended by the objective weighing to increase the rationality and reliability of the total evaluation.What is more,the reliability assessment results based on the fuzzy clustering and synthesis weighing proves to be coincided with those gained through currently existing methods.Thus,the problem of subjective scoring arbitrariness caused by the experts＇ judgment scoring can be more or less avoided with some examples shown,thus improving the objectivity and accuracy of the assessment.Seeing the above said results,the method we have developed proves to be valuable and useful for design and evaluation of the train control system.