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基于遗传Data Farming的公共政策优化仿真模型 被引量:1
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作者 彭敏晶 林健 《系统仿真学报》 EI CAS CSCD 北大核心 2008年第21期5963-5966,5988,共5页
为了解决公共政策优化仿真时考察点不全面及耗费时间大的问题,提出了基于遗传Data Farming的公共政策优化仿真模型。所提出的模型中,Data Farming被用于全面地考察输入参数空间中各输入参数水平对应的输出响应,通过把仿真过程的输出过... 为了解决公共政策优化仿真时考察点不全面及耗费时间大的问题,提出了基于遗传Data Farming的公共政策优化仿真模型。所提出的模型中,Data Farming被用于全面地考察输入参数空间中各输入参数水平对应的输出响应,通过把仿真过程的输出过程看作适应度的计算,遗传算法被用于优化仿真过程,提高优化效率。分析了公共政策作用效果的影响因素,并介绍了传统的Data Farming技术,然后从仿真目标、模型框架、算法等三方面介绍了所提出的优化仿真模型。最后进行了实验,证明了所提出模型的有效性。 展开更多
关键词 DATA farming 遗传算法 公共政策 仿真模型 适应度
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区域经济发展Data Farming决策支持技术及其应用 被引量:1
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作者 彭敏晶 林健 《系统管理学报》 北大核心 2008年第5期514-519,共6页
为解决现有的决策支持技术不能解决的区域经济历史数据稀少的问题,提出了区域经济发展Data Farming决策支持技术。所提出的技术采用基于智能体仿真的Data Farming技术,对参数空间进行遍历搜索,以利用各个参数值对应的仿真结果来获取大... 为解决现有的决策支持技术不能解决的区域经济历史数据稀少的问题,提出了区域经济发展Data Farming决策支持技术。所提出的技术采用基于智能体仿真的Data Farming技术,对参数空间进行遍历搜索,以利用各个参数值对应的仿真结果来获取大量的数据,使决策者可以有效地识别到系统的最优控制值,并了解在控制值下的系统风险性。最后,以江门市社会消费品零售总额的控制优化为例,说明了该技术的有效性。 展开更多
关键词 区域经济 决策支持 DATA farming 智能体仿真 社会消费品零售总额
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韩国贝类养殖(Shellfish Farming)现状及展望
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作者 杨宝瑞 《现代渔业信息》 2005年第8期3-4,共2页
韩国是水产养殖业的主要国家之一。本文作者概述了韩国贝类养殖现状,并展望韩国贝类养殖发展前景。
关键词 韩国 贝类养殖(Shellfish farming) 贝类养殖 养殖现状 展望 水产养殖业 发展前景
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Maize Contract Farming Experience in Delta State,Nigeria 被引量:1
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作者 Albert Ukaro Ofuoku Joseph Unuetara Agbamu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第1期65-73,共9页
Many reviews and evaluations of contract farming and its importance for small-scale farmers in the developing nations have been conducted. While some scholars opined that contractual terms were unfavourable to farmers... Many reviews and evaluations of contract farming and its importance for small-scale farmers in the developing nations have been conducted. While some scholars opined that contractual terms were unfavourable to farmers, others considerd them as being beneficial to them. These contrasting views were not likely to discourage it since it provided encouragement for farmers' involvement in markets. It was therefore worthwhile to investigate previous experiences with the aim of improving on it. This study investigated contract farming entered into by farmers in Delta State of Nigeria and livestock feed companies with the objective of seeking ways to make such contractual agreements beneficial to small-scale farmers. The study utilized convergence of science approach. The study unveiled the constraints experienced by farmers and they included technical and institutional challenges. The technical problem was the planting date, while the institutional problem was the contractual arrangements. It was recommended that all the stakeholders in the contract should converge and negotiate technological adoptions of the improved maize varieties; contract needed to be clearly def'med and risks and uncertainties should be parts of the contract; scientific investigations should be carded out to determine the best planting date; and there was need for legislation to particularly protect farmers in contract farming. 展开更多
关键词 contract farming convergence of science yellow maize FARMER livestock feed company
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Effects of Human Trafficking on Household Farm Labor Availability Among Arable Farming Households in Delta State,Nigeria
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作者 Albert Ukaro Ofuoku Bethel Chuks Uweru 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期70-78,共9页
Trafficking in persons, especially women and girls has been on for long and is still going on. Persons in the female group constitute the mostly trafficked humans. This study was conducted to determine the effects of ... Trafficking in persons, especially women and girls has been on for long and is still going on. Persons in the female group constitute the mostly trafficked humans. This study was conducted to determine the effects of human trafficking on household farm labor needs available among farming households. Arable farming households involved in human trafficking were identified and purposively selected for this study with the aid of key informants in purposively selected communities. This led to the selection of 60 arable farming household heads in Delta North Agricultural zone, 65 farming household heads in Delta Central Agricultural Zone, and 36 arable farming household heads in Delta south agricultural zone to give a total of 151 respondents. Data for the study were collected with the utilization of questionnaire and interview schedule. The collected data were subjected to statistical analysis with the application of frequency counts, percentages and means derived from 4-point likert-type scale. The hypothesis was tested using Tobit regression analysis. Human trafficking was found to be age and sex selective and the causes of human trafficking included both push and pull factors, such as high income in destination countries poverty, low risk profit, nature of trafficking in persons, ease in control and manipulation of vulnerable women and girls, low risk involved in working in destination countries, lacking of legitimate and fulfilling employment, sex selective migration policies, less access to information and peer pressure. Shortage of household farm labor was experienced by farming households in clearing and brushing of farm land, sowing, weeding, harvesting and processing/storage. Human trafficking was found to affect household labor availability in clearing/brushing of farm land, sowing, weeding, harvesting and processing/storage of farm produce. It is recommended that poverty alleviation programs should be specially organized for poor women, government and NGOs and international agencies should develop strategies to mitigate human trafficking. The government needs to collaborate with community based organizations and law enforcement agencies to create anti-trafficking committee in fanning communities. Community education should be created for the farming communities to emphasize anti-human trafficking with the use of change agents; extension agents should integrate anti-trafficking messages in their interaction with farmers. 展开更多
关键词 human trafficking household farm labour arable farming migration fanning household
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基于精细化叠加尾流模型的海上风电场微观选址 被引量:1
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作者 黄玲玲 陈昊 刘阳 《太阳能学报》 北大核心 2025年第4期477-484,共8页
针对传统的解析尾流叠加模型难以准确反映多台风电机组尾流影响下的风速损耗,而高精度CFD仿真计算时间过长,不适用于风电场机组微观选址优化的问题,基于质量守恒和动量守恒定律推导一种改进尾流叠加模型,并通过与FAST.Farm仿真结果的对... 针对传统的解析尾流叠加模型难以准确反映多台风电机组尾流影响下的风速损耗,而高精度CFD仿真计算时间过长,不适用于风电场机组微观选址优化的问题,基于质量守恒和动量守恒定律推导一种改进尾流叠加模型,并通过与FAST.Farm仿真结果的对比,论证所提改进叠加模型的精确性和快速性。构建一个以全寿命周期成本为目标函数的微观选址模型,并通过自适应被囊群算法求解该模型。通过海上风电场风电机组选址算例结果论证所提算法的有效性和优越性。 展开更多
关键词 海上风电场 尾流 微观选址 FAST.Farm仿真 被囊群算法
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循环水养殖系统应用效果探究
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作者 田由甲 《河北渔业》 2025年第9期16-19,共4页
为探究循环水养殖系统(Recirculating Aquaculture System, RAS)的应用效果,以吉富罗非鱼(Genetically Improved Farmed Tilapia,Oreochromis niloticus)养殖为研究对象,选择“中威1号”吉富罗非鱼鱼苗,分别设置对照塘、观察塘两个池塘... 为探究循环水养殖系统(Recirculating Aquaculture System, RAS)的应用效果,以吉富罗非鱼(Genetically Improved Farmed Tilapia,Oreochromis niloticus)养殖为研究对象,选择“中威1号”吉富罗非鱼鱼苗,分别设置对照塘、观察塘两个池塘进行吉富罗非鱼养殖试验,对照塘采用传统养殖模式,观察塘采用循环水养殖系统。试验结果表明,观察塘中吉富罗非鱼的收获规格显著高于对照塘(P<0.05),养殖效率显著高于对照塘(P<0.05);观察塘中吉富罗非鱼的终末体质量(FBW)、特定生长率(SGR)、肥满度(CF)、肝体指数(HSI)和内脏指数(VSI)均显著高于对照塘(P<0.05);观察塘出水口水体中NH+4-N、NO-2-N、COD的含量与对照塘的差异不显著(P>0.05),去除率显著高于对照塘(P<0.05)。这说明采用循环水养殖系统能显著改善吉富罗非鱼的生长性能,提升吉富罗非鱼成鱼规格,降低罗非鱼死亡率,净化养殖水体水质,提高吉富罗非鱼养殖的经济效益。 展开更多
关键词 吉富罗非鱼(Genetically Improved Farmed Tilapia Oreochromis niloticus) 循环水养殖系统 养殖效率 经济效益
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上游风力机偏航对于下游风力机气动特性的影响
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作者 徐强 徐宗原 +2 位作者 朱霄珣 陈军 高晓霞 《可再生能源》 CAS CSCD 北大核心 2024年第6期760-766,共7页
针对倾斜尾迹导致下游风力机受到不平衡的气动载荷,疲劳载荷显著增加的问题,文章基于FAST.Farm开源软件,研究了在NREL 5 MW风力机错列布局下,上游风力机偏航对于下游风力机气动特性的影响。研究结果表明:随着上游风力机偏航角度的增加,... 针对倾斜尾迹导致下游风力机受到不平衡的气动载荷,疲劳载荷显著增加的问题,文章基于FAST.Farm开源软件,研究了在NREL 5 MW风力机错列布局下,上游风力机偏航对于下游风力机气动特性的影响。研究结果表明:随着上游风力机偏航角度的增加,下游风力机逐渐处于尾流风速亏损的核心区域,其风轮输出功率的减少量显著增大,风轮所承受的推力逐渐降低;相较于上游风力机未偏航的情况,当上游风力机偏航角度为40°时,下游风力机叶根处倾覆力矩的标准差增加了50.5%,波动性显著增大。该研究结果可为整场控制协同优化和偏航入流下的风力机气动特性分析提供参考。 展开更多
关键词 风力机 错列布局 FAST.Farm 偏航控制 气动特性
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莫高窟第23窟“雨中耕作图”粟特文化因素解析 被引量:2
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作者 赵玉平 《农业考古》 CSSCI 北大核心 2009年第4期123-127,共5页
Put the Dunhuang Grottoes No.23 of "farming drawing" bottom-left corner of "Rain farming drawing" as the "Lotus Sutra" of the "Overture".Use the Image Study by the methods of an... Put the Dunhuang Grottoes No.23 of "farming drawing" bottom-left corner of "Rain farming drawing" as the "Lotus Sutra" of the "Overture".Use the Image Study by the methods of analysis of Sogd Clothing,Sogd Dance,Sogd Music,Sogd Tower and Xianshouniao(衔绶鸟) behind the pictorial information of the Sogdian(Zoroastrianism)culture. 展开更多
关键词 Dunhuang RAIN farming DRAWING Sogd style Sogdians Xian(祆)
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舟山海域特定水道潮流能估算 被引量:18
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作者 王智峰 周良明 +1 位作者 张弓贲 王爱芳 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第8期27-33,共7页
对舟山海域高亭水道5个站位、灌门水道8个站位的连续26 h实测潮流资料进行分析。结果表明:高亭水道和灌门水道均为不规则半日潮,各站总的垂向平均流速在1 m/s以上。介绍了国际上常用的估算潮流能的方法:Farm方法和Flux方法,并用这2种... 对舟山海域高亭水道5个站位、灌门水道8个站位的连续26 h实测潮流资料进行分析。结果表明:高亭水道和灌门水道均为不规则半日潮,各站总的垂向平均流速在1 m/s以上。介绍了国际上常用的估算潮流能的方法:Farm方法和Flux方法,并用这2种方法分别对高亭水道和灌门水道潮流能进行估算。近似得到高亭水道可开发潮流能功率在4.67-5.31 MW之间,灌门水道可开发潮流能功率在7.92-9.37 MW之间。综合2水道可开发潮流能,换算成1 a的发电量,约占舟山市2005年用电总量的6%~7%。 展开更多
关键词 潮流能 高亭水道 灌门水道 Farm方法 Flux方法
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BES-Ⅱ快速数据重建(英文) 被引量:2
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作者 荣刚 张家文 +2 位作者 郭义庆 张少强 赵棣新 《核电子学与探测技术》 CAS CSCD 北大核心 2002年第2期105-110,共6页
报道了 BES- 快速数据重建的方法和结果 ,基于一个小型 PC FARM或一个分布式的网络Linux PC系统 ,发展建立了 BES- 快速数据重建系统。利用这一系统 ,BES- 实验组可以在数据采集后 2 0 min内完成完整的数据重建。用一台奔腾 (P - 80... 报道了 BES- 快速数据重建的方法和结果 ,基于一个小型 PC FARM或一个分布式的网络Linux PC系统 ,发展建立了 BES- 快速数据重建系统。利用这一系统 ,BES- 实验组可以在数据采集后 2 0 min内完成完整的数据重建。用一台奔腾 (P - 80 0 ) PC微机 ,12 min可以完成 30 0 0 0个由 BEPC(北京正负电子对撞机 )在质心系能量为 3.0 97Ge V处 e+e-对撞产生并由北京谱仪记录的数据的完整重建。利用这些重建的数据 ,在 BES- 实验中可以跟踪检查数据获取的质量 ,及时地解决硬件系统可能出现的问题 ,优化各子探测器硬件参数的设置。 展开更多
关键词 北京谱仪 BES-Ⅱ 北京正负电子对僮机 快速数据重建 PC FARM LINUX 数据采集
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基于FARM的我国股市流动性溢价的实证研究 被引量:2
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作者 刘向华 胡飞 《统计与决策》 CSSCI 北大核心 2012年第19期165-170,共6页
流动性风险和流动性溢价是影响资产价格的重要因素。基于自由流通量调整的收益模型假设系统流动性风险为资产价格的风险因子,资产的流动性价差与其自由流通额的倒数成比例。中国股票市场全流通条件下的股本结构为利用FARM模型研究流动... 流动性风险和流动性溢价是影响资产价格的重要因素。基于自由流通量调整的收益模型假设系统流动性风险为资产价格的风险因子,资产的流动性价差与其自由流通额的倒数成比例。中国股票市场全流通条件下的股本结构为利用FARM模型研究流动性风险与流动性溢价提供了十分有利的条件。文章通过选取2006年7月至2010年6月深圳股票市场与上海股票市场共1168只样本股进行实证分析。 展开更多
关键词 FARM 流动性风险 自由流通量 DCC-GARCH模型
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Effect of Organic and Inorganic Phosphorous on Growth of Roselle(Hibiscus sabdariffa L.) 被引量:1
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作者 Hasnain Alam Muhammad Razaq +1 位作者 Salahuddin Jaffar Khan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期23-30,共8页
To investigate the performance of organic and inorganic phosphorous on growth of Roselle (Hibiscus sabdariffa L.), an experiment was carried out at Newly Developmental Farm (NDF), Horticulture Section, the univers... To investigate the performance of organic and inorganic phosphorous on growth of Roselle (Hibiscus sabdariffa L.), an experiment was carried out at Newly Developmental Farm (NDF), Horticulture Section, the university of Agriculture Peshawar, Pakistan, during 2012. The experiment was laid out in a Randomized Complete Block Design (RCBD) with split plot arrangement and replicated three times. The chemical fertilizer Single Super Phosphate (SSP) was used as inorganic source of phosphorus, while Organic Phosphate (OP) from organic product produced by Niha corporation containing 20% organic mineralized P205, was used as the source of organic phosphorous. Both the sources of fertilizer were applied at the rate of 10, 20, 30 40 and 50 kg. hm2 and control. The statistical analysis of data revealed that both the sources and levels of phosphorus significantly affected most of the growth parameters of Roselle except germination percentage and survival percentage. Plant height (112.09 era), numbers of leave plant1 (177.87), numbers of branch plant1 (4.08), leaf areas (126.60 cm2), days to flowering (142.83), fresh flower weight (2.56 g), fresh calyx weight (1.70 g), dry calyx weight (0.43 g), numbers of calyces (94.10), numbers of root plant-1 (11.03), root length (22.67 cm) and root weight (27.50 g) were observed in plants fertilized with organic source of phosphorous. Phosphorous levels significantly affected all of the parameters except germination percentage and survival percentage. The maximum plant height (124.39 cm), numbers of branches (5.32), numbers of leave plantl (204.89), leaf areas (148.14 cm2), fresh flower weight (3.32 g), fresh calyx weight (2.04 g), dry calyx weight (0.51 g), numbers of calyces (105.30), numbers of root plant-1 (12.78), root length (24.50 cm) and root weight (29.94 g) were observed in plants fertilized with 40 kg. hm-2 phosphorous and the maximum numbers of days to flowering (148.17) were observed in the control plants. It was concluded from the experimental results that organic phosphorous at the rate 40 kg. hm2 would be used for better production of Roselle under agro-climatic condition of Peshawar. 展开更多
关键词 organic farming organic phosphorous ROSELLE
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Conceptual Analysis of Contractual Relationship in Dairy Supply Chain 被引量:1
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作者 Yan Ji Wang Gang-yi Li Cui-xia 《Journal of Northeast Agricultural University(English Edition)》 CAS 2017年第1期70-79,共10页
Dairy industry is the pillar of Heilongjiang Province. The contractual relationship of the dairy supply chain played a vital role in the dairy industry for development. The contractual relationship between the main da... Dairy industry is the pillar of Heilongjiang Province. The contractual relationship of the dairy supply chain played a vital role in the dairy industry for development. The contractual relationship between the main dairy farming body and the dairy processing enterprise, as well as the impact of this contractual relationship on their cooperation in dairy supply chain were studied. Taking 366 dairy farming bodies in Heilongjiang Province as the main research objects, Likert scale was used to measure the factors affecting the contractual relationship and applied these factors to the correlation construction of dairy farming body and processing enterprise. Then, confirmatory factor analysis was used to collect data and made the conclusion that once dairy farming body perceived the opportunistic behavior and lacking of cooperation, the trust of dairy processing enterprise would be lost. Additionally, the satisfaction of dairy farming body on partnership also had a positive effect on the level of trust and commitment, the relative dependence and the perception of the partnerships, which made it possible to analyze how to strengthen the contractual relationship and provide theoretical basis for dairy industry development in Heilongjiang Province. 展开更多
关键词 dairy supply chain contractual relationship dairy farming body dairy processing enterprise
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一个高效可靠的Web farm系统
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作者 魏文国 张凌 +1 位作者 董守斌 谢赞福 《计算机工程与设计》 CSCD 2004年第6期856-858,共3页
针对Web服务器的特点,给出了基于集群的高效、可靠的Web farm系统的体系结构,并对其中负载均衡技术、集群并行文件系统和高可用性支撑环境3大关键技术的设计和实现进行了分析和论述。实验表明:该系统使Web farm的性能得到很大提升,可用... 针对Web服务器的特点,给出了基于集群的高效、可靠的Web farm系统的体系结构,并对其中负载均衡技术、集群并行文件系统和高可用性支撑环境3大关键技术的设计和实现进行了分析和论述。实验表明:该系统使Web farm的性能得到很大提升,可用性也明显改善。 展开更多
关键词 WEB farm系统 集群 负载均衡 并行文件系统 高可用性
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借鉴发达国家经验完善我国兽药残留控制运行机制
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作者 徐士新 汪明 《中国动物检疫》 CAS 北大核心 2006年第1期4-6,共3页
关键词 兽药残留 控制运行 发达国家 机制 动物源食品 借鉴 食品安全工作 食品生产 FARM 欧美国家
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晚清近代化农事试验场的科研活动探讨
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作者 魏露苓 《农业考古》 CSSCI 北大核心 2009年第4期65-72,共8页
In the late Qing Dynasty,after the western modern agricultural science and technology were introduced into China,agricultural experiment farms of every degree were set up for the sake of agricultural education and usa... In the late Qing Dynasty,after the western modern agricultural science and technology were introduced into China,agricultural experiment farms of every degree were set up for the sake of agricultural education and usage.The agricultural experiment farms included both big ones and small ones,supported by either government or private finance.Despite of all the difficulties,research work was done on the farms.On the big and normal ones,the experiments contained modern elements,including chemical fertilizer,machines,good breeds of plants and animals,sericulture and forestry.Though the experiments belonged to primary level and had no much effect on the agriculture of that time,it was gained by effort,in the hard times of the late Qing Dynasty.The found of the agricultural experiment farms showed the change of Chinese agriculture from traditional into modern one. 展开更多
关键词 the LATE QING DYNASTY agricultural experiment FARM SCIENTIFIC research
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SWOT Analysis and Countermeasures of Ecological Agricultural Development of Jianshan Farm
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作者 Cao Can Wang Da-qing +1 位作者 Wang Hong-yan Dai Lin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第1期12-21,共10页
At present, the excessive use of the fertilizers and pesticides in the agricultural production has result in hardening of the soil and decrease of the wild animals and can not maintain the sustainable using of land re... At present, the excessive use of the fertilizers and pesticides in the agricultural production has result in hardening of the soil and decrease of the wild animals and can not maintain the sustainable using of land resources. To develop ecological agriculture is a powerful measure to reduce energy consumption, protect environment, and realize the sustainable development of the agriculture. In order to promote the sustainable development of agriculture in Jianshan Farm, this paper by using SWOT analysis method analyzed the strength, weakness, opportunity and threat in the development of the ecological agriculture in Jianshan Farm, based on the experience from domestic and foreign ecological agricultural development, and put forward the countermeasures for the development of the ecological agriculture in order to develop ecological circular agriculture and non-genetic soybean crop protected areas, and to establish soybean-corn rotation area and healthy aquaculture zone, as well as develop new energy industry. 展开更多
关键词 Jianshan Farm SWOT analysis ecological farming COUNTERMEASURE
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Plan of Using Modern Agriculture High-New Information Technology for Building Stable Nation Commercial Grain and Green Agriculture Base of China
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作者 XUXin-liang ZHANGShu-wen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第2期133-138,共6页
The North-East China is nation commercial grain base of China.It provides important grain supply for other areas of the country every year.The nation and modern farmers are looking for advanced technological solutions... The North-East China is nation commercial grain base of China.It provides important grain supply for other areas of the country every year.The nation and modern farmers are looking for advanced technological solutions to increase production and preserve environment.Considering of this aim,this paper introduce a new planning that using 3S technology to develop precision farming,explaining its technology frame,operation steps and advantages.On the other hand,this paper also introduce the concept of precision farming and discusses the role of 3S technology as a data collection,management and analysis tool. 展开更多
关键词 precision farming 3S technology high-new information technology
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Notice to Contributors about Agricultural Engineering
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《农业工程》 2013年第5期171-172,共2页
The Agricultural Engineering is a comprehensive academic journal under the charge of Chinese Academy of Agricultural Mechanization Sciences,and sponsored by Beijing Prominion Publishing Co,.Ltd.It is launched in2011 u... The Agricultural Engineering is a comprehensive academic journal under the charge of Chinese Academy of Agricultural Mechanization Sciences,and sponsored by Beijing Prominion Publishing Co,.Ltd.It is launched in2011 under CN 11-6025S and ISSN 2095-1795.The journal aims to interpret agricultural engineering policies,focus on innovations and breakthroughs with key technologies in all fields of agricultural engineering,integration 展开更多
关键词 AGRICULTURAL interpret AGRICULTURE STOCK farming F
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