FMEA SECURITY RISK ASSESSMENT OF RAILWAY SIGNAL SYSTEM BASED ON EVIDENCE THEORY AND GREY RELATIONAL ANALYSIS

摘要

In view of the characteristics of the differences among the different experts in the security risk assessment of the railway signal system, and the inaccuracy of the traditional Failure Mode and Effect Analysis assessment by calculating Risk Priority Number, the new assessment method based on evidence theory and grey relational analysis is proposed. Firstly, the result of each rating is evaluated by each expert. Evidence theory is applied to identify conflict evidence. Then, the final weight of the evidence is determined by the fusion of its consistency weight, decentralized weight, and the expert's own weight. The original evidence is corrected by the final weight, thus solving the characteristics of the differences among the different experts. Finally, each expert evaluates the failure modes of the railway signal system, when the evaluation result is corrected again, the grey relational analysis is used to calculate the relational degree. Therefore, the final assessment result can be obtained according to its priority ranking. Compared with the traditional Failure Mode and Effect Analysis, the evaluated result by this means is more accurate. The interface module between the Train Control Center and the Centralized Traffic Control has been taken as an example to verify its credibility and accuracy.