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试论人口与耕地资源剪刀差模式及农村人地工程对策 被引量:1
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作者 罗剑朝 《农业现代化研究》 CSCD 北大核心 1989年第6期7-10,共4页
动态地考察人口与耕地资源的数量变化发现:人口的发展呈上升趋势,而耕地的发展呈下降趋势。这种人口与耕地资源发展的反向变化,我们称其为人口耕地资源“剪刀差”模式。本文从规范与实证两个方面分析了它存在的必然性及其产生的生态效应... 动态地考察人口与耕地资源的数量变化发现:人口的发展呈上升趋势,而耕地的发展呈下降趋势。这种人口与耕地资源发展的反向变化,我们称其为人口耕地资源“剪刀差”模式。本文从规范与实证两个方面分析了它存在的必然性及其产生的生态效应,认为:为了避免我国农村人口的盲目膨胀和耕地资源的大量非农占用、消耗所产生的负生态效应,应该全面实施“农村人地工程”,并提出了实施“农村人地工程”的主要措施。 展开更多
关键词 人口 耕地 资源 农村 人地工程
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试论人口与耕地剪刀差及农村“人地工程”对策
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作者 罗剑朝 《自然资源》 CSCD 北大核心 1990年第5期41-47,共7页
一、问题的提出 土地是农业的基本生产资料,它既是农业劳动力劳动投入的吸纳体,又是人类改造和利用动植物生理机能以获得一定要求的农产品的主要手段。一定数量的农产品产出,必须以一定数量和质量的土地投入为前提。也就是说,土地数量... 一、问题的提出 土地是农业的基本生产资料,它既是农业劳动力劳动投入的吸纳体,又是人类改造和利用动植物生理机能以获得一定要求的农产品的主要手段。一定数量的农产品产出,必须以一定数量和质量的土地投入为前提。也就是说,土地数量的多少和质量的好坏,往往决定着土地生产率及土地承载量的大小。作为土地主要组成部分的耕地资源,是农产品产出乃至农产品总供给的基础资源之一。在传统农业时期,由于农业投入的短缺和工业发展水平的限制。 展开更多
关键词 人地工程 人口 耕地 剪刀差
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高低压供电线路入地工程施工探讨 被引量:1
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作者 罗文斌 《机电信息》 2014年第33期102-103,共2页
近年来,随着我国经济的不断发展,各地区的基础设施建设也在不断地完善。过去,我国的高低压供电线路总是以高空架线的形式运行,这在某种程度上影响了地区风貌,同时高架线路也给人们的生命安全造成了一定的威胁。为了改善这种状况,我国大... 近年来,随着我国经济的不断发展,各地区的基础设施建设也在不断地完善。过去,我国的高低压供电线路总是以高空架线的形式运行,这在某种程度上影响了地区风貌,同时高架线路也给人们的生命安全造成了一定的威胁。为了改善这种状况,我国大部分地区开始加强高低压供电线路入地工程的建设,但在高低压供电线路入地工程施工过程中仍然存在很多问题。现结合多年工作经验,对高低压供电线路入地工程施工过程中的相关注意事项进行了探讨。 展开更多
关键词 高低压供电线路 人地工程 施工 注意事项
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认人地困境中的粮食发展对策
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作者 黄贤金 《国土开发与整治》 1993年第2期20-25,共6页
关键词 人地关系 粮食 人地工程
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Design of Constructed Wetland for Treatment of Tailwater from Wastewater Treatment Plant 被引量:2
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作者 李昆 王玲 +2 位作者 李兆华 苗纪法 王祥荣 《Agricultural Science & Technology》 CAS 2015年第3期568-572,582,共6页
In this study, the project of constructed wetland for treatment of tailwater from the wastewater treatment plant in Wudang Mountain was taken as an example, and the technological processes, pollution load, wetland bed... In this study, the project of constructed wetland for treatment of tailwater from the wastewater treatment plant in Wudang Mountain was taken as an example, and the technological processes, pollution load, wetland bed structure, bed filler, selection of plants and hydraulic conditions of the subsurface flow constructed wetland were discussed. A subsurface flow constructed wetland, which covered an area of 7 227 m^2 was finally designed. It could treat 7 000 m^3 of tailwater from the wastewater treatment plant a day. In addition, the system could reduce the emission of COD, BODs, TN, TP and NH3-N by 25.55, 25.55, 12.78, 1.28 and 17.89 t respectively a day. The outlet water was proved to reach the Standard A of the first class in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002). 展开更多
关键词 TAILWATER Subsurface flow constructed wetland Engineering design
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Application of artificial slope stability evaluation of improved response surface method in Donggang Power Plant
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作者 LI Xiangli 《Global Geology》 2014年第1期38-43,共6页
The study of artificial slope stability has been a key item of geological engineering projects. Though more evaluation methods are available,result of stability evaluation simulation does not explain the actual proble... The study of artificial slope stability has been a key item of geological engineering projects. Though more evaluation methods are available,result of stability evaluation simulation does not explain the actual problem owing to the diversified geological engineering factors and complexity. The author made a detailed study based on surveys of large amount of geological engineering research on Donggang Power Plant slope project,discussed the comprehensive factors influencing the project,and gave analytical calculation and evaluation to the improved response surface of the slope project. The study result shows that the slope is stable,which can provide scientific basis for designing the slope. 展开更多
关键词 SLOPE improved response surface method RELIABILITY plastic deformation STABILITY
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Localization and navigation using a novel artificial landmark for indoor mobile robots
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作者 温丰 《High Technology Letters》 EI CAS 2009年第3期233-238,共6页
This paper presents a practical topological navigation system for indoor mobile robots, making use of a novel artificial landmark which is called MR code. This new kind of paper-made landmarks earl be easi- ly attache... This paper presents a practical topological navigation system for indoor mobile robots, making use of a novel artificial landmark which is called MR code. This new kind of paper-made landmarks earl be easi- ly attached on the ceilings or on the walls, lmealization algorithms for the two cases are given respective- ly. A docking control algorithm is also described, which a robot employs to approach its current goal. A simple topological navigation algorithm is proposed. Experiment results show the effectiveness of the method in real environment. 展开更多
关键词 mobile robot LOCALIZATION NAVIGATION artificial landmark topological map
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