Due to the epistemic uncertainty, it is difficult for the experts to give precise parameter values in Risk Priority Number (RPN) evaluations. To overcome this drawback, a hybrid method is proposed by integrating the concepts of fuzzy set theory, weight analysis and similarity value measure of fuzzy numbers. The analysis process is divided into two phases to identify the hazard source. The first phase uses fuzzy Fault Tree Analysis (FTA) and Failure Mode and Effect Analysis (FMEA), then the main potential failure modes can be determined. The importance analysis of basic events can be calculated using fuzzy set theory and weight analysis. In the second phase, the multiple failure modes and component correlations are modelled using the Fuzzy Risk Priority Number (FRPN) evaluation and the Similarity Measure Value Method (SMVM). The proposed method has been applied to the risk analysis of a satellite propulsion system to show the effectiveness and applicability.

中文翻译：

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FMEA中基于相似性度量和加权模糊风险优先级数的推进系统风险分析

由于认知上的不确定性，专家很难在风险优先级数字（RPN）评估中给出精确的参数值。为了克服这一缺点，提出了一种融合模糊集理论，权重分析和模糊数相似值度量的混合方法。分析过程分为两个阶段，以识别危险源。第一阶段使用模糊故障树分析（FTA）和故障模式与影响分析（FMEA），然后可以确定主要的潜在故障模式。基本事件的重要性分析可以使用模糊集理论和权重分析来计算。在第二阶段，使用模糊风险优先级数字（FRPN）评估和相似性度量值方法（SMVM）对多个故障模式和组件相关性进行建模。