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新疆棉花“订单农业+期货”模型的构建与实证研究
作者: 徐春华   来源: 石河子大学 年份: 2010 文献类型 : 学位论文 关键词: 最小方差套期保值   传统套期保值   价格发现   棉花期货   订单农业  
描述: nd its ability to resist the risk of price fluctuation is fluctuating in relatively weak, so they often become the most direct victims for the rapidly cotton price, reducing the cotton farmers'enthusiasm to grow cotton .The cotton
全文:履约风险。本文通过构建新疆棉花“订单农业+期货”模型,分析棉花数据,为涉棉企业找到最佳套期保值策略,转移价格风险,实现利益最大化。 本文采取定性分析与定量分析相结合,实证分析与规范分析相结合,对构建
黄河流域农业立体污染综合防治模式研究
作者: 杨永坤   来源: 中国农业科学院 年份: 2010 文献类型 : 学位论文 关键词: 农业立体污染   综合模式   黄河流域   仿真模型  
描述: he paper studies from the situation and feature of Agriculture Tri-dimension Pollution in Yellow River Basin areas, and divides it into several regions according to basin’s pollution feature by adopting the method of searching documents , research, systems analysis, quantitative and qualitative analysis and so on, and analyzes the problem of Agriculture Tri-dimension Pollution in Yellow River Basin areas from the view of tri-dimension and system by use of the theory of Environmental value, Technology Value, Ecology, Circular economy , uses System Dynamics to track dynamically the change in the future of the various variables in different modes and constructs the system mode of agricultural tri-dimension pollution in Yellow River Basin, and simulates the system;
全文:。论文研究取得了一下主要结论: 1、首次利用系统动力学方法构建的防治农业立体污染系统仿真模型与系统评价方法可靠。仿真技术建立的黄河流域农业立体污染综合防治技术模式在银川平原引黄灌区案例区实地验证结果表明:2001-2004年农业立体污染防治系统模型分析结果与案例区实测结果基本符合,最大相对误差<9.5%,最小误差
西部干旱地区农户旱地种植行为实证研究
作者: 叶晶晶   来源: 南京农业大学 年份: 2010 文献类型 : 学位论文 关键词: 农户   旱地   水资源   决策   干旱风险  
描述: ncentrated v}}ith 85% of the total dry lands. and it is important for the national economy and the countr<0's strategic agricultural growth. Northwest arid areas basically depend on natural precipitation. water shortage has seriously affected the farmers practices. The decision of farmers to plant dry land is a two-stage decision-making behavior: They first have to decide whether to plant dry land, and then decide what kind of crops planted in the dry lands. It is essential to find effective ways to raise the enthusiasm of farmers planting and reasonable arrangements for dry land crop structure. However. ver}} few people study dry land farming practice from the perspective of water shortages.
全文:。第四章首先根据前人的理论成果经过提炼提出了本文的研究假说,然后介绍了模型的选择和变量的定义,分析了变量的预期影响效果,然后分别利用二元选择Probit模型和多元排序选择Ordered Probit模型
当代中国新型农村公共服务体系研究
作者: 方堃   来源: 华中师范大学 年份: 2010 文献类型 : 学位论文 关键词: 新型农村公共服务体系   “服务三角”模型   整体性治理   碎片化  
描述: lions of farmers, greatly emancipated and developed the rural productive forces, and fundamentally improved the majority of farmers' production and living conditions. The economy and society of rural area in China has undergone
全文::(1)理念和视角新颖。本文以“促进城乡统筹与基本公共服务均等化”为理念,从现代系统管理科学的视角,对我国农村公共服务体系的碎片化问题进行审视,系统地研究了基于“服务三角”模型的新型农村公共服务体系构建
考古资料所见汉代河洛地区的农业
作者: 江亚冰   来源: 郑州大学 年份: 2010 文献类型 : 学位论文 关键词: 农业   汉代   河洛地区  
描述: Han Dynasties, this region was paid more attention to for its special political status.
全文:模式。大量且分布广泛的储粮明器、粮食加工工具的出土以及丰富的食品种类足以证明当时河洛地区的粮食产量极高,农业经济非常发达。遍及河洛地区的陶制家畜家禽以及圈舍模型的出土给我们展现了汉代该地区饲养业兴旺发展的景象,也从侧面反映出其农业经济的发达、繁荣。
陕西省农业现代化对农民增收的关系研究
作者: 雷婷   来源: 西北农林科技大学 年份: 2010 文献类型 : 学位论文 关键词: 陕西省   农民增收   农业现代化  
描述: e’ stability.This paper sets Shaanxi province as an example,hope to find the main factors affecting the income of peasants and their contribution in the system of the agricultural modernization, so as to identify the means of raising income of farmers from the view of the agricultural technology.
全文:代表性、概括全面的农业现代化指标,采用层析分析法,建立层次结构模型,构造判断矩阵,计算各级权重,构建一个农业现代化指标评价体系。选择浙江省为参照物,对各指标进行标准化,通过与标准值的对比来衡量陕西省
甘肃省黄河沿岸地区水资源承载能力分析
作者: 刘建兰   来源: 兰州大学 年份: 2010 文献类型 : 学位论文 关键词: 甘肃省   沿黄地区   水资源   承载能力   系统动力学  
描述: th, the demand of water resource is continuously increasing. That is to say water shortage has become a global problem. Water resources carrying capacity is the basis and prerequisite of regional socio-economic development, which is significant to realize the coordinated development of regional "water resources- ecological environment-socio-economy" composite system. So it has become the focus and hot topic in water science field nowdays.
全文:水资源概况,通过构建水资源承载能力的系统动力学模型,对水资源承载能力的动态变化进行了分析。结果表明:农田灌溉面积、灌溉定额、节水技术、非农产业规模以及生态用水几个变量对水资源承载力的影响较大,为主
基于~(137)Cs技术的中国北方农牧交错带土壤侵蚀研究
作者: 姜洪涛   来源: 内蒙古师范大学 年份: 2010 文献类型 : 学位论文 关键词: 土壤侵蚀   农牧交错带   ~Cs   示踪  
描述: ttention, but also agriculture and eco-environmental sustainable development important problems. Farming-pastoral Transitional zone in north China, as our county returning farmland to forest and returning cropping land to grassland are the focus areas, natural environment and socio-economic conditions shown a clear transition characterized by the transition zone of the interpenetration and staggered distribution of agriculture and animal husbandry, which is curbing desertification important ecological barrier, but also ecologically fragile belts.
全文:Walling和He提出的质量平衡模型及~(137)Cs深度分布的扩散和迁移复合过程物理模型分别计算耕作土壤与非耕作土壤侵蚀速率。兰州不同土地利用类型的土壤侵蚀速率范围为1200-76000t/k m
甘肃省黄河沿岸地区水资源承载能力分析
作者: 刘建兰   来源: 兰州大学 年份: 2010 文献类型 : 学位论文 关键词: 甘肃省   沿黄地区   水资源   承载能力   系统动力学  
描述: th, the demand of water resource is continuously increasing. That is to say water shortage has become a global problem. Water resources carrying capacity is the basis and prerequisite of regional socio-economic development, which is significant to realize the coordinated development of regional "water resources- ecological environment-socio-economy" composite system. So it has become the focus and hot topic in water science field nowdays.
全文:水资源概况,通过构建水资源承载能力的系统动力学模型,对水资源承载能力的动态变化进行了分析。结果表明:农田灌溉面积、灌溉定额、节水技术、非农产业规模以及生态用水几个变量对水资源承载力的影响较大,为主
西北旱作农区农作制优先序研究
作者: 成敏   来源: 西北农林科技大学 年份: 2010 文献类型 : 学位论文 关键词: 西北旱作农区   BP神经网络   农作制优先序   抗旱减灾对策?  
描述: est region, which c ombined with the water-saving, agricultural soil and water conservation techniques, and then taken " drought resistance, reduce erosion, increase efficiency" as a principle.
全文:了以资源节约高效利用、抗旱减灾为主的农作制以及合理有效的抗旱减灾对策。主要得出以下结论: (1)通过在甘肃天水、定西、平凉、庆阳地区,宁夏银南地区、固原地区,陕西宝鸡、咸阳、渭南、铜川、延安、榆林
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