基于模糊隶属度的雷电危险度等级评定

利用2013—2017年青海省西宁市测站半径10 km的闪电定位监测数据，选取地域范围一小时内的地闪数目和一小时内的最大雷电流幅值作为雷电危险度因子。确定因子分级的上下限和因子区间划分，计算出单因子雷电危险度等级的隶属度与权重。采用梯形分布函数和模糊统计方法确定雷电危险度因子的隶属度函数，根据隶属度函数得出模糊矩阵，并进行模糊矩阵复合运算，求出雷电危险度综合指数，得出雷电危险度等级。结果表明：根据建立的模糊综合评判方法能够全面、客观、准确地反映一次闪电过程的危险度状况，有效评定雷电危险度等级，评定结果较为客观地反映了雷击事件的实际状况，从而为气象防灾减灾、雷电灾害调查和雷击风险评估等业务提供科学性的决策服务和参考依据。

Assessment of lightning hazard degree based on fuzzy membership

Assessment of lightning hazard grade is an important part of disaster risk evaluation and disaster management.The establishment of a scientific assessment method of lightning hazard grade can reflect the dangerous condition of a lightning strike event comprehensively,objectively and accurately.It is urgent and important to evaluate and divide the lightning hazard by effective ground method.Based on the monitoring data about ground flicker in Xining area of Qinghai Province,China for 5 years,this paper takes the frequency of ground flicker and the amplitude of lightning current as risk factors to determine the ground flicker frequency and the upper and lower limits of lightning current amplitude of the research data.The membership function of lightning hazard factor is determined by using trapezoid distribution function and fuzzy statistical method.On the basis of determining the weight of each factor,combining the index weight with the factor set,the multilevel assessment of lightning risk is carried out.The paper evaluates the lightning hazard degree of two cases and the results show that the fuzzy comprehensive evaluation method is simple and effective in the research method of lightning hazard grade evaluation,and its evaluation results objectively reflect the actual situation of lightning strike event and the conclusion of the research method is consistent with the results of the accident investigation and lightning disaster investigation.Compared with other methods,this method can accurately give the lightning hazard grade of different lightning current amplitude and different lightning number.