In this paper, we present an integrated framework for quantifying epistemic uncertainty in probabilistic risk assessment. Three types of epistemic uncertainty, that is, completeness, structural and parametric uncertainties, are considered. A maturity model is developed to evaluate the management of these epistemic uncertainties in the model building process. The impact of epistemic uncertainty on the result of the risk assessment is, then, estimated based on the developed maturity model. Then, an integrated risk index is defined to reflect the epistemic uncertainty in the risk assessment results. An indifference method is developed to evaluate the index based on the maturity of epistemic uncertainty management. A case study concerning a nuclear power plant is shown to demonstrate the applicability of the overall modelling framework.

在本文中，我们提出了一个用于量化概率风险评估中认知不确定性的集成框架。考虑了三种类型的认知不确定性，即完整性，结构性和参数性不确定性。建立了成熟度模型，以评估在模型构建过程中这些认知不确定性的管理。然后，基于已开发的成熟度模型，估计认知不确定性对风险评估结果的影响。然后，定义一个综合风险指数以反映风险评估结果中的认知不确定性。根据认知不确定性管理的成熟度，开发了一种无差异方法来评估指标。展示了有关核电厂的案例研究，以证明总体建模框架的适用性。