Multi-Objective Decision Making And Risk Analysis Of Limited Water Level Of Controlling With Reservoir

With the rapid development of China economy and increase of population, the serious problem faced with China is more and more deepened. The problems about optimal scheduling of reservoir are very complex as the all kinds of factors for example uncertainties, time-variant and nonlinear, therefore,the reservoir's conflict between flood control and its benefit.The dissertation is based on the flood as resources and multi-objective decision making approach and risk analysis when raising limited water level of controlling flood at flood season. The writer analyzed widely existed research positive result and issues then work out below:●Enhance the comprehensive benefits with adopting fuzzy regulating limited water level of controlling flood at flood season based hierarchical flood by stages;●Employ multi-objective decision making approach to optimally select scheme(s) at different limited water level of controlling flood at flood season;●Make reservoir exert biggest benefits at suitable flood safety through risk analysis ; All of the methods above provide scientific foundation to scheme reasonably reservoir.The main research positive result and research contents be given below:(1) It be summarized that the existed advanced research position result about hydrology forecast ,reservoir and water resource regulation, risk analysis with the dam and lower reach of reservoir. The runoff series of incoming water with the reservoir occur to changes compared to designed data because of transformation underlying surface , mankind's large scale of water intake, use, consumption and drainage as well as global climate changes. The dissertation put forward calculate the flood frequency once again so that the hydrological statistics conform to the truthful circumstances as the policies of adaptability because of the changes above.(2) It also be put forward fuzzy regulating limited water level of controlling flood at flood season based hierarchical flood by stages. The method utilize different limited water level of controlling flood at different stage , there the benefit be raised with the reservoir on the condition of constant flood risk and the so-called hierarchically raising flood limited water level of controlling flood is that we raise it further when the flood frequency is less than the designed frequency. The certain flood frequency of seasonal maximum flood frequency curve is less than it of designed flood frequency curve according to the research position result . So we must calibrate every seasonal flood frequency in order to make it is the same value to the designed flood frequency of main flood period. The dissertation put forward that adopt inter-temporal maximum flood frequency to calculate seasonal designed flood frequency in order that the other seasonal flood frequency is the same value to the designed flood frequency of main flood period. And topological structure figure also be given.(3) It be clarified that essential theory about multi-objective decision making approach including the basic concept, weighting, producing Pareto solution. It gives the some typical methods including ELECTRE method, TOPSIS method and PROMETHEE method. The dissertation put forward we should adopt varied ways to the same problem when dealing with the water resource and reservoir distribution and then we contrast the different ways combining the knowledge and experiences, at last draw the scientific optimal scheme. It be set up that the multi-level hierarchical model of large scale system which is the effective curse of dimensionality about reservoir schedule based on input/output of water resource .This model don't make local economic benefit maximize but whole maximize on the condition that the reservoir risk is as the sub-system of the model. So the model has higher reality and reliability.(4) It be summarized that the basic methods and principles about risk analysis of reservoir scheduling and analyzes the flood-prevention risk of dam and lower reaches about reservoir. It also deduced strictly the formula of flood-prevention risk rate of lower reaches about reservoir which adopt probability theory and the result is reliable.(5) It be given that the example of Zhanghewan-Resrevoir applying the theory which be discussed above. It includes fuzzy regulating limited water level of controlling flood of Zhanghewan-Resrevoir at flood season based hierarchical flood by stages, varied multi-objective decision making approachs including ELECTRE method, TOPSIS method and PROMETHEE method and gets the reasonable result finally.It be computed that the risk rate of reservoir dam taking three different limited water level of controlling flood at flood season which is respectively 478.5m/479.5m/480.5m.It draw the conclusion that the limited water level of controlling flood of Zhanghewan-Resrevoir at flood season is able to be raised 480.5m.(6) The end of the dissertation make summarize about full text and kook into the future to the related content.