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排序方式: 共有93条查询结果,搜索用时 15 毫秒
1.
本文根据胶合板厂实际情况,建立了杨木胶合板厂生产规划模型。该模型考虑各主要设备工段、产品组合、产品混合、产品价格、流动资金、原材料供应以及市场约束等问题。本模型能够满足市场竞争,获取最佳利润,同时还能解决胶合板厂“三板”(表、背、芯单板)不平衡问题。  相似文献   
2.
Crop production in Georgia and the Southeastern U.S. can be limited by water. Highly-weathered, drought-prone soils are susceptible to runoff and erosion. Rainfall patterns generate runoff producing storms followed by extended periods of drought during the crop growing season. Thus, supplemental irrigation is often needed to sustain profitable crop production. Increased water retention and soil conservation would efficiently improve water use and reduce irrigation amounts/costs and sedimentation, and sustain productive farm land, thus improving producer's profit margin. Soil amendments, such as flue gas desulfurization (FGD) gypsum, have been shown to retain rainfall and/or irrigation water through increased infiltration while decreasing runoff (R) and sediment (E). Objectives were to quantify rainfall partitioning and sediment delivery improvements with surface applied FGD gypsum from an Ultisol managed to conventional till (CT) and to assess the feasibility of using FGD gypsum on agricultural land in southern Georgia. A field study (Faceville loamy sand, Typic Kandiudult) was established (2006, 2007) near Dawson, GA managed to CT, irrigated cotton (Gossypium hirsutum L.). FGD gypsum application rates evaluated were 0, 1.1, 2.2, 4.5, and 9 Mg ha− 1. Gypsum treatments and simulated rainfall (50 mm h− 1 for 1 h) were applied to 2-m wide × 3-m long field plots (n = 3). Runoff and E were measured from each 6-m2 plot (slope = 1%). FGD gypsum plots averaged 26% more infiltration (INF), 40% less R, 58% less E, 27% lower maximum R rates (Rmax), and 2 times lower maximum E rates (Emax) than control plots. Values of INF and water for crop use increased, and R, E, Rmax, and Emax decreased as FGD gypsum application rate increased. Values of INF, R, E, Rmax, and Emax for 9 Mg ha− 1 plots were as much as 17% greater, 35% less, 1.9 times less, 35% less, and 1.9 times less than those from other FGD gypsum plots, respectively; and 40% greater, 40% less, 2.2 times less, 52% less, and 2.9 times less than those from control plots, respectively. Applying FGD gypsum to agricultural lands is a cost-effective management practice for producers in Georgia that beneficially impacts natural resource conservation, producer profit margins, and environmental quality. Agriculture in the Southeast provides a viable market for the electric power industry to convert disposal costs of FGD gypsum into a profitable commodity.  相似文献   
3.
为研究木薯皮、鸡粪在蔗区套种模式中的还田施用效果,分别设置化肥配施木薯皮(T1)、配施鸡粪(T2)、配施半量木薯皮和半量鸡粪(T3)3个处理,以甘蔗单种化肥处理(CK1)或甘蔗套种花生化肥处理(CK2)为对照,比较各处理作物产量、品质、效益及花生秸秆还田后土壤肥力的变化。结果表明,T1、T2、T3与CK2相比,大大增加了花生产量、纯收益,花生秸秆还田后土壤速效氮磷钾含量明显提高;T1处理的纯收益最高,比CK1处理增收花生3720.9 kg hm~(-2),增加纯收益17675.4元hm~(-2),但该处理对花生粗脂肪及甘蔗产量有一定负面影响;T2处理的花生产量、总效益和花生秸秆还田后的土壤速效氮磷钾、有机质含量最高,比CK1处理增收花生4270.8 kg hm~(-2);T3处理比CK1处理增收花生3904.2 kg hm~(-2),花生粗脂肪含量达51.3%,增加纯收益17442.15元hm~(-2),还提高了花生秸秆还田后的土壤速效氮磷钾、有机质含量。综合考虑,甘蔗套种花生(化肥配施半量木薯皮和半量鸡粪)是较好的种植和养分管理模式,值得大面积推广。  相似文献   
4.
关于沼气式循环型农业模式探讨   总被引:12,自引:0,他引:12  
王芳  雷海章 《安徽农业科学》2006,34(8):1647-1648,1650
分析了沼气式循环型农业模式的多重循环效益,提出了当前推广该模式的政策建议。  相似文献   
5.
陈燕  刘蜀凤 《安徽农业科学》2012,(36):17894-17895
移动电子商务已成为电子商务领域发展的方向.分析我国移动电子商务的发展现状,指出农业移动电子商务在商业模式、盈利模式、消费习惯、支付等方面存在的问题并提出相应对策.  相似文献   
6.
This article discusses the determinants of profitability expressed as return on capital among Japanese pulp and paper companies. Return on capital is measured as income before tax related to stockholders’ equity. Return on capital has been divided into profit margin and asset utilization rate. The hypothesis is that return on capital can be explained by mill size, productivity, product line, financial situation, and use of wood resources. The dataset consists of 13 larger Japanese pulp and paper companies listed in Pulp &; Paper Statistics. Data on financial performance, production, and use of wood fibers were collected for the period 1991–2001. The average return on equity for the studied companies is 4.2%. Labor productivity has increased quite significantly, from about 600 to 1,000 kg/employee and year. An econometric analysis indicates that the best model fit is found when the asset utilization rate is used as the dependent variable. Significant variables are, among others, asset utilization rate lagged one time period (?), labor productivity (+), capital productivity (?), paper production as a share of total paper and board production (?), total value of assets on the books (?) and solidity (+). This may indicate that the total value of assets on the books is large in relation to the total production of paper, paperboard and pulp.  相似文献   
7.
农村合作经济组织利益机制研究   总被引:1,自引:0,他引:1  
莫少颖 《安徽农业科学》2007,35(21):6671-6672,6687
农业各种合作经济组织的兴起和壮大,为解决农民进入市场、保护农民利益和提高农业的经济效益提供了保障。在分析农村合作经济组织的利益联结机制及其运行中存在问题的基础上,对完善农村合作经济组织利益机制提出若干对策建议。  相似文献   
8.
选择主成分分析法,并在充分调研、专家咨询的基础上,本着定性指标和定量指标兼顾,绝对指标、相对指标和平均指标相结合的原则,确定了能够用来衡量农村信用社盈利能力的若干指标。认为农村信用社要实现可持续发展的长远战略目标,必须从现在起把能力建设作为重要战略基点,谋求在农村金融领域中的规模和优势,进行技术创新、制度创新、人力资源能力建设、外部环境培育。  相似文献   
9.
为了明确氮、钾肥对大葱产量和经济效益的影响,开展了多年施用不同数量的氮、钾肥对大葱产量和经济效益的影响试验。结果表明,增施钾肥对大葱生长发育有明显的促进作用,并能显著提高产量。白庙和黄岭地区试验在氮肥(纯N)水平为225、300 kg/hm~2时,大葱经济产量分别增加11.9%~16.8%和13.2%~21.1%,平均分别增长13.9%、16.7%,大葱产量均随钾肥施用量的加大而提高。在氮肥低用量条件下,适当增加氮肥施用量,也能有效提高大葱的经济产量,不同钾肥(K2O)用量下施氮肥大葱可增产9.9%~14.8%,平均增产12.5%;其中,白庙地区大葱产值增收26 160~41 900元/hm~2,产投比为20.22~43.21。  相似文献   
10.
首先对农产品供应链的信息不对称性成因进行了分析,其次在信息不对称的理论框架下对供应链的运作机理和特征进行了总结,最后对信息不对称条件下农产品供应链的利润分成进行了模型分析,提出了相关的意见和建议,为农产品供应链的定价权和利润分配提供参考.  相似文献   
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