A Study On The Comprehensive Evaluation Model Of Urban Flood System

Flooding has been a continuing challenge to the development and growth of our country. Although significant improvements and achievements have been made in the flood control and prevention area during the 60 years of PRC history, the situation is still very serious. It’s largely due to the climate and environmental changes related to the significant increase of human activities. An urban flood prevention plan is a cornerstone to the heathy development of a city. For a city under rapid development and growth, urban flood prevention plan will have broad social, political, economical and environmental impacts. Thus establishing an effective and comprehensive evaluation model for urban flood prevention plan will have a significant impact on creating and implementing such a plan.Based on the current assessment researches, this paper 1st reviewed the engineering and non-engineering measures related to urban flood prevention, as well as the measurements of their impacts and relationships. Based on that, a measurement system is established for and applied to urban flood prevention evaluation. From there, studies are done related to neural network, the principles and characteristics of the gray system theory and genetic algorithms. Based on their application conditions, advantages and disadvantages, a genetic algorithm optimizing gray neural network is composed for urban flood prevention system evaluation. A comprehensive evaluation model is further developed involving multiple measurements on impacts. This model is based on MATLAB software platform but can be run independently. Through pre-processing the impact measurement data for urban flood prevention using gray system theory, and identifying the optimal initial weights and thresholds for neural network using genetic algorithms, as well as training the neural network using sample data, the comprehensive evaluation for flood prevention plan for Shenyang city is finally achieved. A new way to evaluate the urban flood preventions plan is thus established, involving both soft and hard measures holistically.