A System Safety Assessment Method Considering Risk Correlation

ABSTRACT The safety of the system is affected by a variety of risk factors such as human, machine, environment, and management, and the risk factors interact with each other and are not independent. Describing the dynamic trends in the operational safety of a system with coupled risk factors is difficult. Therefore, a safety assessment method based on the IOWA‐IM‐FCM model is proposed. Combining the interval‐ordered weighted average (IOWA) operator to build an interaction matrix (IM) of risk factors. It can better express the fuzzy relationship between risk factors while weakening the influence of subjective factors and identifying key risk factors. Next, the IM elements are substituted into the fuzzy cognitive map (FCM) model to predict the system safety risk trends under the influence of risk factor interactions. Finally, the results of the analysis of the IM and the FCM model are integrated, and the system safety evaluation level is determined by the risk evaluation coefficient. The method was applied to a case study of a bogie system. Results indicate the bogie system operation risk is general, matching the real scenario. The method realizes quantitative prediction of the system risk trend under the coupling of risk factors with certain advantages.