基于信息扩散技术的华南极端台风灾害风险评估

Risk assessment of extreme typhoon disasters based on information diffusiontechnology

利用2005-2016年登陆华南地区的12个极端台风灾害样本,综合考虑了承灾体脆弱性和防灾减灾能力,对华南地区进行极端台风灾害风险评估,步骤如下:1)以各指标的灰色关联度为基础,构造华南极端台风的危险性指数、脆弱性指数和防灾减灾能力指数;2)根据灾害风险数学表达式,以层次分析法确定的系统权重为基础,构造华南地区极端台风灾害风险指数;3)通过二维正态扩散技术构造原始信息矩阵和模糊关系矩阵,利用因素空间理论进行模糊近似推理,计算得到由风险指数近似估计直接经济损失指数的风险估计值;4)利用超概率评估模型,对极端台风的直接经济损失率进行超概率评估。结果表明,构造的风险指数与实际情况较为吻合,计算得到的风险估计值与直接经济损失指数变化趋势较为一致,均方误差为0.20,相关系数为0.78。结果还表明,由极端台风造成的直接经济损失率为0.1%,已成为常态风险,华南地区极端台风灾害的超越概率与直接经济损失率呈现出良好的线性关系。

Based on 12 cases of extreme landfalling typhoon disasters in South China from 2005 to 2016,extreme landfalling typhoon disaster risk assessment in South China was carried out by considering the vulnerability of disaster bearers and the ability of disaster prevention and mitigation.First,based on the grey relational degree of each index,the risk index,vulnerability index and disaster prevention and mitigation ability index of extreme typhoons in South China are constructed.Then,according to the mathematical expression of disaster risk,based on the system weight determined by analytic hierarchy process,an extreme typhoon disaster risk index in South China is constructed.Next,the original information matrix,fuzzy relation matrix and factor space theory are constructed by using two-dimensional normal diffusion technology.In this paper,the fuzzy approximate reasoning is carried out to obtain the risk estimate value of the direct economic loss index estimated by the risk index approximately.Finally,the super probability evaluation model is used to evaluate direct economic loss rate of each extreme typhoon.The results show that the constructed risk index is in good agreement with the actual situation,and the calculated risk estimate is consistent with the change trend of direct economic loss index,the mean square error is 0.20,and the correlation coefficient is 0.78 The results also show that the direct economic loss rate caused by extreme typhoons is 0.1%,which means it has become the normal risk,the transcendence probability and direct economy loss rate of extreme typhoon disaster in South China shows a good linear relationship.