基于云模型和证据理论的铁路信号系统风险评估

Risk Assessment of Railway Signal System Based on Cloud Model and Evidence Theory

为科学合理地对铁路信号系统进行风险评估,针对评估过程中模糊性和随机性等不确定性问题,以及采用专家经验进行评估的特点,提出基于云模型和证据理论的铁路信号系统风险评估模型。首先采用云模型对专家评语信息进行建模,利用得到各风险因素的隶属度构造评语基本信度分配函数;然后采用证据理论进行信息融合,得到各风险因素基本信度分配函数;最后利用层次分析法确定风险因素权重,通过线性加权进行综合,得到最终评估结果。以无线闭塞中心为例利用该模型进行风险评估,验证了该模型的合理性和有效性,为铁路信号系统风险评估提供参考。

In order to evaluate the risk level of a railway signal system more scientifically and more reasonably,to deal with the uncertainty problems resulting from fuzziness and randomness during the process of risk assessment,and to conduct risk evaluation based on expert experience,a risk evaluation model for railway signal system was proposed based on the cloud model and evidence theory.First,a cloud model was used to model the expert comment information,to comment the basic probability assignment function with membership structure of different risk factors derived.Then,the evidence theory was applied to fuse the information,to obtain basic probability assignment of risk factors.Finally,the weight of each risk factor was determined by using the analytic hierarchy to acquire the final evaluation results through integration by linear weighting.The model was used to evaluate the risk level of radio block center.The results proved the rationality and validity of the model,which can provide a reference for the risk assessment of railway signal systems.