Study On Modeling & Optimization About Irrigation System Of Well Irrigation Rice In Sanjiang Plain

The content of the thesis is a part of "China Postdoctoral Science Fund" na COi na Pos on Irrigation Management DSS of Saving Water & Increasing Temperature for Well Irrigation Rice on Sanjiang Plain." Through building models and usin Trro ug hbui 1 d ng m the writer eager to provide some academic gist for the continuum development about agriculture and water resource.Sanjiang Plain is the most important base of commodity grain of China. The area under cultivation of well irrigation for rice has been expanding year after year of lately year. There are 0.7 million hm2 of rice area by the end of 1998. And nearly 80 percent are well irrigation. The homeostasis of groundwater resources has been destroyed because of exploiting by human without plan. More and more pumps can't work and the appearance of funnel has been arisen. So, the lacking of groundwater resources has been become the restricted factor for its development.Aim at the above problems, the writer uses the modern modeling and optimum technique to studying the well irrigation rice in Fujin Area in Sanjiang Plain. Through handling lots of testing data, the writer builds up the model of non-stable time series model to forecasting the well irrigation rice water requirement in Sanjiang Plain. At the same time, the author analyses the random characteristic of rainfall and selects the season time series model to forecasting the rainfall. According to the least twin multiplication to calculating the sensitivity index in several water production functions. Thus, the writer obtains the fitted the value of the sensitivity index and the varied rule. At the same time, the writer puts forward a new method named RAG A (Real coding based Accelerating Genetic Algorithm) and combines RAGA with DPSA to calculating the best irrigation system under the non-sufficient irrigation of well irrigation rice in Sanjiang Plain. The best irrigation system can instructs the best distributed water quantity and the irrigated time under the condition of lacking water. Thus, we can obtain the maximum relative yield and the least loss. Thus, through building models and optimization, we not only can provide the models that can instruct to irrigating, but also have the important significance to advancing the provision yield and handle the water resource crisis.Postgraduate: Wang LikunSupervisor: Liu QinghuaMajor: Water and Soil of Agricultural Engineering...