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农户分化背景现代农业微观组织发育机制研究
作者: 丁慧媛   来源: 中国海洋大学 年份: 2009 文献类型 : 学位论文 关键词: 发育机制   农户分化   现代农业微观组织  
描述: construction in the new century.
全文:的方法、定量分析与定性分析相结合的方法以及系统分析的方法,通过以下六个部分,对我国农户分化背景的现代农业微观组织的发育机制进行了分析和探讨: 第一部分绪论,主要阐述了研究背景,研究目的和意义,简要
植物河道水流特性和稳定河相关系研究
作者: 王燕   来源: 中国海洋大学 年份: 2009 文献类型 : 学位论文 关键词: 仙农熵   水流特性   生态河流   根系加固   河相关系  
描述: made for economic prosperity. At the same time, some man-made natural disasters have been paid more and more attentions , so the research on hydraulic characteristics of the river in recent years has been put on the agenda. Considering the ecological environment, flood control, pollution prevention and control method, and in view of the perspective of the urban landscape as well as the national strategic plan for sustainable development, the research the hydraulic characteristics of river and making river reasonably repair and ecological reconstruction will become a general trend, because that is a kind of remediation measure for human to be done unreasonable exploitation, and it also will be the strong protection of river resources and sustainable model for better using river resources in the future.
全文:植被前后的水流特性变化情况与河宽动力调整过程,并进行了相应的理论研究;引入植物的种植密度,考察在不同种植密度的情况对河宽调整的影响关系,得出相关的糙率拟合公式;在能量均衡关系的基础上,利用仙农熵的理论
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