Research On Optimal Flood Control Operation For Poyang Lake Semi-restoration Dikes

Semi-restoration Dikes as a way of the project of re-conversion of reclaimed lands to wetlands, it is an important part of comprehensive flood control system. While the critical moment of Flood control, they can be brought into play reducing . the flood peak and resorting excess flood, immolating the local and protecting the overall situation, reducing flood disaster losses of effective measures and an important means of flood control operation. A good way of scientific and rational use of Semi-restoration Dikes, which can effectively reduce the flood crest of rivers and lakes, and the downward flow can be reduced, it can ensure the safety of embankments downstream and reducing downstream flood control pressure. Therefore, research on the reasonable flood control operation program for Semi-restoration Dikes ought to give full play to flood control for Semi-restoration Dikes and the operation for agricultural production to provide a scientific basis.The flood control operation for Semi-restoration Dikes is a global optimization problem, arbitrary changes in local, will affect the overall situation, so it is a complex systems engineering. Variable fuzzy set theory can be integrated into the knowledge and experiences of people, the policy makers take part in them, and to consider each goal in the degree of importance of the goals, but also to quantify qualitative targets. This paper is to use variable fuzzy set theory and methods to study on the flood control programs for Poyang Lake Semi-restoration Dikes, and determine the optimal flood control program for Semi-restoration Dikes.Conclusions are the following:(1) Apply multi-level fuzzy optimization theory for flood control operation decision-making to establish the flood control program fuzzy optimization model for Semi-restoration Dikes. In the optimization model consider the quantitative targets of flood diversion effect, economic losses and storage capacity as fuzzy optimization factors for operation program, and optimize the flood control operation programs. Finally, we will acquire an optimal flood control operation program for Semi-restoration Dikes.(2) Apply semi-structural decision-making theory for flood control operation to establish the flood control program fuzzy optimization model for Semi-restoration Dikes. In the optimization model not only consider the quantitative targets of flood diversion effect, economic losses and storage capacity as a fuzzy optimization factors for operation program, but also consider the qualitative target of entironment as a fuzzy optimization factor, and optimize the flood control operation programs. Finally, we will acquire a optimal flood control operation program for Semi-restoration Dikes.(3) With flood control operation for Poyang Lake Semi-restoration Dikes as an example, we will choose the 1998 as a typical representative year of the floods in successive years, using the established fuzzy optimization model, and computing the flood control operation for Poyang Lake Semi-restoration Dikes(including the following ten thousand Mu and the above ten thousand Mu). Comparison of calculation results of the two models, we will acquire a optimal program of flood control operation for Semi-restoration Dikes. The program is: When the water level of Hukou reached 20.5 meters, the first open the following ten thousand Mu Semi-restoration Dikes. If the water level continues to rise, when the water level of Hukou reached 22.5 meters, then open the above ten thousand Mu Semi-restoration Dikes. On the basis of the optimal flood control operation for Semi-restoration Dikes, in this paper, using semi-structured decision-making methods to optimize the flood control operation programs of the following ten thousand Mu Semi-restoration Dikes. And acquire a flood control operation program of Poyang Lake following ten thousand Mu Semi-restoration Dikes. The optimal program will provide basis for scientific flood control of Poyang Lake district.