Dissertation
Dissertation > Environmental science, safety science > Environmental Quality Assessment and Environmental Monitoring > Analysis and Evaluation of Environmental Quality > Biological assessment, ecological assessment

An Application of Genetic Projection Pursuit Method on Ecological Evaluation

Author LiuHaiJuan
Tutor LuFan
School Lanzhou University
Course Applied Mathematics
Keywords projection pursuit genetic method evaluation of ecologicalsecurity economic comprehensive evaluation maize borer prediction
CLC X826
Type Master's thesis
Year 2013
Downloads 33
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Projection pursuit model is always used to deal with data in higher dimen-sional space. The fundamental thread of projection pursuit method is that:it projects data in higher dimensional space to lower one. By analyzing the pro-jected data in lower dimensional space, projections that reflect the structure or rule of higher dimensional space will be found. In this way, the objective data in higher dimensional space can be mastered. During this process, the construction of objective projection function, the selection of optimal method as well as the model of mathematical method are all the keys to solve the practical problems.Three kinds of projection pursuit models discussed in this paper respectively are:interpolation model, classification model and regression model. The projection pursuit interpolation model is used to evaluate the ecological security of six towns of Minqin in Gansu province. By using the projection pursuit classification model, we analyzed and ordered the total economic conditions of four districts of Wuwei in Gansu province. Also, by analyzing the past breaking data of maize borer in some place, this paper predicted its next tide time by using projection pursuit regression model. As a result, some conclusions are obtained as follows:(1) The ecological security of all of the six towns, Minqin, Changning, Caiqi, Suwu, Shuangcike, Hongshaliang and Nanhu, are not very well. Where, Caiqi is approximate unsafe, Changning, Suwu and Hongshaliang are relative unsafe, and Shuangcike and Nanhu are unsafe. These results strike an alarm to the safety of ecological system of Minqin. How to break wind and fix sand, so that ecological level can be improved, is the major government jobs of Minqin.(2) From the total economic analysis of the four districts in Wuwei, we can see that the conditions of Liangzhou, Minqin, Gulang and Tianzhu is on a descending order. Compare to large cities, the economy of Wuwei is quite worse. How to find a suitable economic model, basing on the terrain, climate, natural resource as well as the development tendency of Wuwei, to improve its economic level is an severe challenge.(3) The predict result of maize borer’s breaking time with the projection pursuit regression model is stable and accurate. It also fits with the practical situation, we can do some defensive measures by analyzing the past data, so that the breaking time of maize borer can be reduced, and consequently coin production can be raised, which will surely contribute to increasing in crop yield.

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