Amendment Of PPDC Model And Its Application Research In The Risk Zoning Of Storm Surge Disaster

With the changing of global climate, marine disaster occurs frequently, which causes the size of loss to expand constantly and threat seriously the sustainable economic and social development as well as public safety in the coastal areas. In this case, the work of disaster prevention and compensation has been taken seriously by countries and all levels of government At the same time, risk management and monitoring of disasters is also raised to the national public safety and social stability at the strategic level. The issue of risk assessment and zoning has become an important strategic issue concerning economic development in coastal areas. Besides, it relates to the successful implementation of the global maritime power and the improvement of the overall strategy for regional development. Therefore, the conduct of marine disaster risk zoning has very important significance for finding out the base of marine disaster prevention and maximizing to circumvent disaster risk.Paper selects the storm surge as main hazard and 11 coastal provinces as the research objects. The final index system of storm surge is determined by using rough set theory, and using modified PPDC model analyzes risk zoning of coastal provinces’ storm surge.Firstly, the article defines the concepts of storm surge and risk zoning, and elaborates the formation mechanism of the storm surge risk and theory of disaster risk zoning; Secondly, PPDC method of this paper is to be corrected:the advantage of genetic algorithm and particle swarm optimization is combined to form a hybrid particle swarm algorithm, and using the hybrid particle swarm algorithm optimize the projection index in PPDC model to achieve improvements of PPDC model; Thirdly, on the basis of risk identification and factor analysis of storm surge disaster in coastal provinces, considering the theory of disaster risk and designing principles of index system, a more comprehensive risk assessment system of coastal storm surge is established; Finally, in the basis of the application of rough set theory to filter index and establish the final index system, utilizing modified PPDC model analyze risk zoning of storm surge in 11 coastal provinces. The results shows that:storm surge risk of 11 coastal provinces can be divided into three categories, Guangdong and Fujian are classified as a class, which is at high risk area; Shandong, Zhejiang, Hainan and Guangxi are classified as a class, which is at middle risk area; Jiangsu, Tianjin, Liaoning, Hebei and Shanghai are classified as third category, which belongs low risk area.Discussion innovation in the paper:one is that it is different from the establishment of the evaluation index system of storm surge disaster in the past, the rough set theory is introduced storm surge disaster risk assessment to eliminate redundant indicators to establish the most simple index system of disaster risk, which improves the effectiveness of the evaluation; the other is that it uses hybrid algorithm to optimize the index function because of the defects of a single algorithm (such as particle swarm optimization), which can avoid falling into local optimum and effectively improve the accuracy and speed of the optimization. Therefore, it realizes the correction of the PPDC model, at the same time, it improves the accuracy and reliability of the risk zoning.