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Research on the development of electric agricultural machinery technology based on patent information
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作者 LIU Qin HU Lianglong GAO Ya 《智能化农业装备学报(中英文)》 2025年第4期64-72,共9页
This study takes the patent information of China's electric agricultural machinery technology as the research object,and uses patent measurement analysis method and visual analysis tools to carry out statistical a... This study takes the patent information of China's electric agricultural machinery technology as the research object,and uses patent measurement analysis method and visual analysis tools to carry out statistical analysis and comparative research on the relevant patent information from the perspectives of annual patent applications,patent structure,technological key,main applicants,patent layout,technology lifecycle and so on.The research results show that China's electric agricultural machinery technology innovation is developing rapidly,and the patent categories are mainly utility model and invention patents,and the proportion of invention patents is lower than utility model patents.Universities are the most important innovation subjects in this field,and technology research and development focuses on IPC(international patent classification)subcategories such as A01C(seeding,fertilization),B60K(power,transmission),and A01D(harvesting.mowing).Jiangsu Province and Shandong Province rank the top 2 in the number of domestic patent applications,and the United States and Japan are the two countries with the most layout in China.At present,the growth of electric agricultural machinery technology is weak,but the new technology has strong features,there is no sign of maturity,and it does not have signs of technological aging and still has greater development potential.The results of the study can provide information reference for clarifying the status quo,characteristics and development trend of China's electric agricultural machinery technology innovation. 展开更多
关键词 China electric agricultural machinery technology development patent analysis technology lifecycle IPC
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DEVELOPMENT AND ERROR ANALYSIS OF AN INSPECTING SYSTEM FOR MEASURING THE ROTATIONAL INERTIA OF BULLETS 被引量:15
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作者 车英 李占国 +3 位作者 陈礼华 白素平 马宏 韩文波 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算... 介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算公式,分析了产生测量误差的因素,进行了定量精度分析,给出了实验结果与测量精度。 展开更多
关键词 转动惯量 摆动周期 测量误差 development AND ERROR ANALYSIS OF AN INSPECTING
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Future development of solid oxide fuel cell 被引量:1
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作者 李箭 杨新民 蒲健 《电池》 CAS CSCD 北大核心 2006年第5期396-397,共2页
Solid oxide fuel cell(SOFC) technology and its status and problems were briefly described.Several topics for furtherresearch and development were proposed.
关键词 solid oxide fuel cell future development RESEARCH
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Resource allocation optimization of equipment development task based on MOPSO algorithm 被引量:8
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作者 ZHANG Xilin TAN Yuejin and YANG Zhiwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1132-1143,共12页
Resource allocation for an equipment development task is a complex process owing to the inherent characteristics,such as large amounts of input resources,numerous sub-tasks,complex network structures,and high degrees ... Resource allocation for an equipment development task is a complex process owing to the inherent characteristics,such as large amounts of input resources,numerous sub-tasks,complex network structures,and high degrees of uncertainty.This paper presents an investigation into the influence of resource allocation on the duration and cost of sub-tasks.Mathematical models are constructed for the relationships of the resource allocation quantity with the duration and cost of the sub-tasks.By considering the uncertainties,such as fluctuations in the sub-task duration and cost,rework iterations,and random overlaps,the tasks are simulated for various resource allocation schemes.The shortest duration and the minimum cost of the development task are first formulated as the objective function.Based on a multi-objective particle swarm optimization(MOPSO)algorithm,a multi-objective evolutionary algorithm is constructed to optimize the resource allocation scheme for the development task.Finally,an uninhabited aerial vehicle(UAV)is considered as an example of a development task to test the algorithm,and the optimization results of this method are compared with those based on non-dominated sorting genetic algorithm-II(NSGA-II),non-dominated sorting differential evolution(NSDE)and strength pareto evolutionary algorithm-II(SPEA-II).The proposed method is verified for its scientific approach and effectiveness.The case study shows that the optimization of the resource allocation can greatly aid in shortening the duration of the development task and reducing its cost effectively. 展开更多
关键词 resource allocation equipment development task multi-objective particle swarm optimization(MOPSO) develop ment task simulation.
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Exploitation of Wild Flowers and the Sustainable Development of Flowers Industry in China 被引量:4
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作者 HONG Li PANG Songling ZHUO Lihuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期76-79,共4页
This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic res... This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development. 展开更多
关键词 wild flowers and plants development and utilization flowers and plants industry sustainable development
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Issues and Development Opportunities of Aquatic Product Industry in China 被引量:5
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作者 GAO Shenrong TONG Xia WU Linhai 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第2期87-91,共5页
China is the largest producer and trader of aquatic products in the world, but does not mean that it belongs to the strongest power group of aquatic production and trade. This paper objectively analyzed the main probl... China is the largest producer and trader of aquatic products in the world, but does not mean that it belongs to the strongest power group of aquatic production and trade. This paper objectively analyzed the main problems existing in the highspeed development of China's aquatic product industry by empirical analysis. For example, the situation of quality and safety of aquatic products is serious now; the basic conditions of aquaculture lag behind the production development; aquatic industry is still in a low level of development and organization; and the quality and safety of aquatic products is the most main problem. This paper also revealed that fish would be the main source of animal-derived food, and the demand of characteristic aquatic products would continuously go up. Aquatic processing has initially formed a standard system. It drew a conclusion that it would be a good opportunity for China's aquatic processing industry in the future 展开更多
关键词 aquatic product development status future opportunity
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Regulation of Foliar Application DCPTA on Growth and Development of Maize Seedling Leaves in Heilongjiang Province 被引量:4
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作者 Gu Wan-rong Meng Yao +4 位作者 Zhang Jun-bao Ji Biao Wang Yong-chao Li Jing Wei Shi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第2期1-11,共11页
DCPTA (2-diethylaminoethyl-3, 4-dichlorophenylether) is a new plant regulator which can be used to regulate growth and development for crops. Experiments on maize seedlings were conducted in the growth chamber to st... DCPTA (2-diethylaminoethyl-3, 4-dichlorophenylether) is a new plant regulator which can be used to regulate growth and development for crops. Experiments on maize seedlings were conducted in the growth chamber to study the effects of foliar applied DCPTA. The plant pots were placed in a completely randomized design with three replicates. The maize seedlings were treated with 0 mg·L-1 (control), 20 mg·L-1 and 40 mg·L-1 DCPTA solution. The effects of DCPTA on the photosynthetic characteristics (photosynthesis, stomata conductance, intercellular CO2, and transpiration rate), related physiological characteristics (contents of soluble sugar and starch), chlorophyll fluorescence parameters (Fo, Fro, Fv/Fm, Fv/Fo, qP, and qN) and the weight of dry matter in maize seedling were studied. The results showed that DCPTA enhanced photosynthesis of maize seedling. In general, photosynthetic rate in leaves was significantly promoted through spraying DCPTA solution, and 40 rag" L~ DCPTA was found to be the best concentration for maize. The relationship between stomata conductance and transpiration rate in maize leaves could be described as linear. With regard to the chlorophyll fluorescence parameters, our fmdings showed that 40 mg·L-1 DCPTA in maize seedling caused an increase in Fm, Fv/Fm, Fm/Fo, qP and a decrease in Fo and qN at some time points checked. It is suggested that DCPTA increased photosynthetic rate by raising both the content of chlorophyll and activities of PSII and the contents of sugar and starch. Compared with the control, the treated maize seedling caused an increase in plant height, root length, shoot dry mass, root dry mass, or the total (root plus shoot) dry mass. 展开更多
关键词 DCPTA PHOTOSYNTHESIS growth and development maize seedling
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A review on lightweight materials for defence applications:Present and future developments 被引量:11
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作者 Suchart Siengchin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期1-17,共17页
The defence sector is now at an advanced level,catering to the global scenario,and countries also invest heavily in research and development.Countries around the world have spent a lot of money on research and develop... The defence sector is now at an advanced level,catering to the global scenario,and countries also invest heavily in research and development.Countries around the world have spent a lot of money on research and development over the years in order to stay ahead of their competitors.Lightweight materials are critical in defence applications because they allow components to be lighter without sacrificing strength.This review provides an overview of the research related to defence applications.The book provides comprehensive details on current trends in the application of lightweight materials in defence.This review also includes historical and current perspectives on defence technologies.It discusses uses of lightweight materials such as metal matrix composites,polymer composites,ceramic matrix composites,fiber composites in defence sectors Finally,the review paper also emphasizes future military applications of lightweight materials. 展开更多
关键词 Lightweight materials DEFENCE TECHNOLOGIES developmentS APPLICATIONS
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Development and Application of a Shaft-type Tubular Pumping System with a Siphon Discharge Passage 被引量:7
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作者 ZHANG Ren-tian ZHU Hong-geng DAI Long-yang 《南水北调与水利科技》 CAS CSCD 北大核心 2013年第1期J0001-J0006,共6页
Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft su... Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft suction box and a siphon-type discharge passage with a vacuum breaker as the cutoff device was developed , which possesses such advantages as simple structure , reliable cutoff , and high energy performance.Taking some pumping stations as the case studies , in the light of the specified operation conditions , the hydraulic optimal design of the shaft-type tubular pumping system was determined and the optimized shape of the system was recommended.The performance prediction based on the computational fluid dynamics methodology was determined and the model test verification was conducted.The results show that the predicted data agree with the experimental head and efficiency so that both methods can be used to determine the performance of a real pumping station.Finally , the in-situ measurements of a pumping station during the commissioning period further verified that the shaft-type tubular pumping station with a siphon discharge passage is of higher efficiency , more reliable and stable. 展开更多
关键词 shaft-type tubular pumping station siphon discharge passage development application hydraulic optimal design model test
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Research Status and Development Direction of Gas-containing Coal Seepage Model 被引量:17
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作者 程波 《矿业安全与环保》 北大核心 2017年第5期93-97,共5页
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Application and Development of Biosensors 被引量:1
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作者 GAO Yuelin LI Jichang HUO Guicheng LIU Libo 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期80-83,共4页
As a new kind of analytical instrument, the principles, types and characters of biosensors were discussed in this paper. A biosensor is usually composed of a recognition element of biological origin and a physicochemi... As a new kind of analytical instrument, the principles, types and characters of biosensors were discussed in this paper. A biosensor is usually composed of a recognition element of biological origin and a physicochemical transducer. The biological element is capable of sensing the presence, activity or concentration of a chemical analyse in solution. The sensing takes place either as a binding event or a biocatalytical event. These interactions produce a measurable change in a solution property, in which the transducer is converted into a quantifiable electrical signal. The principles, types and applications of biosensors in environmental inspection, food production, clinical medicine and military defense were reviewed, and the trends in research were predicated, Furthermore, an attempt had been made to describe the future development directions and prospects. 展开更多
关键词 biosensors development APPLICATION
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Design and Development of TGPSIS Based on SuperMap—Map Subsystem 被引量:1
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作者 LI Changzhi~1 LIU Xingnian~2 CAO Shuyou~2 WANG Zhaoyin~(1,3) (1.China Inst.of Water Resources and Hydropower Research,Beijing 100038,China 2.State Key Lab.of Hydraulics and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China 3.Dept.of Hydraulic Eng.,Tsinghua Univ.,Beijing 100084,China) 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期133-137,共5页
The Three Gorges Project (TGP for short) is the key project to train and develop the Yangtze River of China,with multi-objects of flood defence,electricity generation,shipping,etc.However,sediment plays an important r... The Three Gorges Project (TGP for short) is the key project to train and develop the Yangtze River of China,with multi-objects of flood defence,electricity generation,shipping,etc.However,sediment plays an important role in beth constructing of engineering and exerting efficiency of TGP.Special attention,there- fore,has been paid to sediment problem of TGP since the very beginning of this engineering's pregnancy.Up to now,much observed data and fruitful researches about TGP have come into being,and a sci... 展开更多
关键词 TGPSIS SEDIMENT design and development
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Exploring harmonious development between urbanization and eco-environment based on climate analysis—A study in Changsha, China 被引量:4
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作者 刘少博 魏春雨 +4 位作者 郭亚琦 曾晓霞 柳肃 尹怡诚 刘云国 《Journal of Central South University》 SCIE EI CAS 2011年第1期101-107,共7页
The process of urbanization affects the urban warming.The change of urban warming was investigated by several urbanization factors in Changsha,China.The data of surface temperature(minimum,maximum and mean) of Changsh... The process of urbanization affects the urban warming.The change of urban warming was investigated by several urbanization factors in Changsha,China.The data of surface temperature(minimum,maximum and mean) of Changsha were analyzed to understand the possible effects of urbanization on the climate of this region owing to the population growth,built-up area expansion and energy consumption increases.The weights of these three factors were calculated by the analytical hierarchy process(AHP).Then,three weights were simulated with nonlinear method to obtain the urbanization development rate which was utilized to reveal the influence of the urbanization factors on the surface temperature.The result shows that there is a significant upward trend in the urban temperatures of Changsha.The temperature increase seems to be closely related to the rate of urbanization between 1993 and 2008,and there is an evidential increase trend of the influence on urban temperature by urbanization during 16 years.It is a quantifiable approach measuring the relationship between urbanization and urban eco-environment,and can be applied for the urban sustainability. 展开更多
关键词 URBANIZATION urban warming eco-environment effects harmonious development Changsha
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A new approach for selecting best development face ventilation mode based on G1-coefficient of variation method 被引量:15
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作者 ZHOU Zhi-yong Mehmet KIZIL +1 位作者 CHEN Zhong-wei CHEN Jian-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第10期2462-2471,共10页
The current popular methods for decision making and project optimisation in mine ventilation contain a number of deficiencies as they are solely based on either subjective knowledge or objective information.This paper... The current popular methods for decision making and project optimisation in mine ventilation contain a number of deficiencies as they are solely based on either subjective knowledge or objective information.This paper presents a new approach to rank the alternatives by G1-coefficient of variation method.The focus of this approach is the use of the combination weighing,which is able to compensate for the deficiencies in the method of evaluation index single weighing.In the case study,an appropriate evaluation index system was established to determine the evaluation value of each ventilation mode.Then the proposed approach was used to select the best development face ventilation mode.The result shows that the proposed approach is able to rank the alternative development face ventilation mode reasonably,the combination weighing method had the advantages of both subjective and objective weighing methods in that it took into consideration of both the experience and wisdom of experts,and the new changes in objective conditions.This approach provides a more reasonable and reliable procedure to analyse and evaluate different ventilation modes. 展开更多
关键词 development face ventilation G1 method coefficient of variation method comprehensive evaluation OPTIMIZATION
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2012–2014 China's Earth Observation and Earth Science Development 被引量:2
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作者 GUO Huadong MA Jianwen +4 位作者 XIAO Han LU Feng LIANG Dong BI Haiyun WANG Fangjian 《空间科学学报》 CAS CSCD 北大核心 2014年第5期721-732,共12页
Human beings are now facing global and regional sustainable development challenges.In China, Earth observation data play a fundamental role in Earth system science research. The support given by Earth observation data... Human beings are now facing global and regional sustainable development challenges.In China, Earth observation data play a fundamental role in Earth system science research. The support given by Earth observation data is required by many studies, including those on Earth's limited natural resources, the rapid development of economic and social needs, global change, extreme events, food security, water resources, sustainable economic and urban development, and emergency response. Application operation systems in many ministries and departments in China have entered a stage of sustainable development, and the State Key Project of High-Resolution Earth Observation Systems has been progressing since 2006. Earth observation technology in China has entered a period of rapid development. 展开更多
关键词 EARTH OBSERVATION EARTH system science BIG data HIGH-RESOLUTION EARTH OBSERVATION systems Global and REGIONAL sustainable development
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The Status Quo and Development Trend of High-purity Gold Sputtering Targets 被引量:1
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作者 YANG Anheng XIE Hongchao ZHU Yong 《贵金属》 CAS CSCD 北大核心 2012年第A01期173-176,共4页
This article gives a brief introduction to manufacturers and markets of sputtering targets as well as the manufacturing technology thereof. Then, it analyzes the application of high-purity gold sputtering targets in t... This article gives a brief introduction to manufacturers and markets of sputtering targets as well as the manufacturing technology thereof. Then, it analyzes the application of high-purity gold sputtering targets in the fields of integrated circuit, information storage, flat panel display, etc. Based on the above, the article analyzes the processing development trend for the high-purity gold sputtering targets in aspects of ultra-high purity, manufacturing technology, analysis and testing technologies. 展开更多
关键词 high-purity gold sputtering targets status quo development trend
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The Application of Optimum Decision in Oilfield Development 被引量:1
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作者 Zhang Zaixu Xu Qingshan +1 位作者 Jiang Megifang Hou Fenghua & Yin Aizhen(University of Petroleum of Shandong, Dongying 257061, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第2期5-10,共6页
The major steps of oilfield development are given in this paper. The optimal model of oilfield development is built and the methods of optimum decision analysis are studied. The solution and analysis of the optimal ta... The major steps of oilfield development are given in this paper. The optimal model of oilfield development is built and the methods of optimum decision analysis are studied. The solution and analysis of the optimal tactics have been set up according to the data collected in the oilfield. 展开更多
关键词 Optimum tactics Oilfield development Optimizing model Decision analysis
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Rehabilitation of bauxite residue to support soil development and grassland establishment 被引量:9
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作者 XUE Sheng-guo 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第2期353-360,共8页
Rehabilitation(amendment and vegetation establishment)on bauxite residue is viewed as a promising strategy to stabilize the surface and initiate soil development.However,such approaches are inhibited by high pH,high e... Rehabilitation(amendment and vegetation establishment)on bauxite residue is viewed as a promising strategy to stabilize the surface and initiate soil development.However,such approaches are inhibited by high pH,high exchangeable sodium(ESP)and poor nutrient status.Amendment with gypsum is effective in improving residue physical and chemical properties and promoting seed establishment and growth.Application of organics(e.g.compost)can address nutrient deficiencies but supplemental fertilizer additions may be required.A series of germination bioassays were performed on residue to determine candidate species and optimum rehabilitation application rates.Subsequent field trials assessed establishment of grassland species Holcus lanatus and Trifolium pratense as well as physical and chemical properties of amended residue.Follow up monitoring over five years assessed elemental content in grassland and species dynamics.With co-application of the amendments several grassland species can grow on the residue.Over time other plant species can invade the restored area and fast growing nutrient demanding grasses are replaced.Scrub species can establish within a 5 Yr period and there is evidence of nutrient cycling.High pH,sodicity and nutrient deficiencies are the major limiting factors to establishing grassland on residue.Following restoration several plant species can grow on amended residue. 展开更多
关键词 bauxite residue substrate amendment soil development soil formation in bauxite residue vegetation establishment
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TEDA(Tianjin Economic-technological Development Area)——A General Survey, Experience and the Plan for Future Development. 被引量:2
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作者 Tian gui-ming Chi Chang-gui Wan Qian Spokesman, Director of the Commission Office of TEDA. Visiting Professor of Tianjin Institute of Commerce M. A. of Economies, Vice Director of the Commission Office of TEDA Deputy Chief of Secretary Section of the Commission Office of TEDA Shen Huan 《南开经济研究》 CSSCI 北大核心 1994年第S1期26-34,共9页
Since its establishment about ten years ago, TEDA has taken advantage of eachopportune time created by China’s policy of opening wider and wider to the outsideworld and the rapid economic growth to deepen its reform ... Since its establishment about ten years ago, TEDA has taken advantage of eachopportune time created by China’s policy of opening wider and wider to the outsideworld and the rapid economic growth to deepen its reform and extend its exploitation,and thus has maintained a favorable momentum and an extraordinary high speed foreconomic development. With the total economic output of the whole area raised to 展开更多
关键词 TEDA Tianjin Economic-technological development Area A General Survey Experience and the Plan for Future development
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Rural Development Evaluation from Territorial Function Angle:a Case of Shandong Province 被引量:1
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作者 CHEN Yangfen LIU Yansui 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第1期67-74,共8页
Rural territorial function follows the trend to develop from agricultural production space to a complex of cultural heritage,food security,social stability,quality of living,etc.Based on the rural area's territorial ... Rural territorial function follows the trend to develop from agricultural production space to a complex of cultural heritage,food security,social stability,quality of living,etc.Based on the rural area's territorial function to both urban and rural areas and its evolution law,index system of rural development evaluation,covering rural production function,rural consumption function,regional sustaining function,and individual development function were constructed in this paper.Case study based on Shandong Province and entropy method showed that the rural development in Shandong Province was neither stable nor orderly,and some of rural territorial functions were under fluctuation.The simulation result was close to the actual situation in rural areas of Shandong Province,and therefore,it would provide some experience for scientific evaluation of rural development in other regions.In the end,policy suggestion to cope with rural function transition was provided,namely further promoting the rural economic development,and breaking away from various factors that restricted the value realization,natural increment,and equitable distribution of rural production factors,and therefore,it would receive a sustainable rural development. 展开更多
关键词 rural territorial function rural development EVALUATION entropy method
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