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Spatiotemporal characteristics of cultivated land use eco-efficiency and its influencing factors in China from 2000 to 2020 被引量:1
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作者 LI Shaoting MU Na +1 位作者 REN Yanjun Thomas GLAUBEN 《Journal of Arid Land》 SCIE CSCD 2024年第3期396-414,共19页
Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China t... Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China to evaluate the spatiotemporal evolution of CLUE from 2000 to 2020 and identified the influencing factors of CLUE by using a panel Tobit model.In addition,given the undesirable outputs of agricultural production,we incorporated carbon emissions and nonpoint source pollution into the global benchmark-undesirable output-super efficiency-slacks-based measure(GB-US-SBM)model,which combines global benchmark technology,undesirable output,super efficiency,and slacks-based measure.The results indicated that there was an upward trend in CLUE in China from 2000 to 2020,with an increase rate of 2.62%.The temporal evolution of CLUE in China could be classified into three distinct stages:a period of fluctuating decrease(2000-2007),a phase of gradual increase(2008-2014),and a period of rapid growth(2015-2020).The major grain-producing areas(MPAs)had a lower CLUE than their counterparts,namely,non-major grain-production areas(non-MPAs).The spatial agglomeration effect followed a northeast-southwest strip distribution;and the movement path of barycentre revealed a"P"shape,with Luoyang City,Henan Province,as the centre.In terms of influencing factors of CLUE,investment in science and technology played the most vital role in improving CLUE,while irrigation index had the most negative effect.It should be noted that these two influencing factors had different impacts on MPAs and non-MPAs.Therefore,relevant departments should formulate policies to enhance the level of science and technology,improve irrigation condition,and promote sustainable utilization of cultivated land. 展开更多
关键词 cultivated land use eco-efficiency(CLUE) slacks-based measure(SBM)model barycentre model standard deviation ellipse(SDE) panel Tobit model carbon emissions nonpoint source pollution
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Insights from i-Tree Eco-efficiency Assessment Management of Urban Trees in Oxford,UK
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作者 YANG Xin LI Bowen LI Sha 《Journal of Landscape Research》 2024年第4期1-4,12,共5页
In the era of stock development following the acceleration of urbanization,the revitalization of urban green space has assumed an increasingly significant role.Consequently,the management of urban trees has emerged as... In the era of stock development following the acceleration of urbanization,the revitalization of urban green space has assumed an increasingly significant role.Consequently,the management of urban trees has emerged as a critical focus of urban governance,contributing to the enhancement of livability in human settlements.This study offers a comprehensive analysis of the urban tree management system in Oxford,UK,identifying that its primary objective is to optimize and maintain a harmonious balance between human activities and the natural environment through the implementation of high-quality planting practices.The system emphasizes enhanced management practices and establishes a robust framework for the development of targeted policies and management regulations,utilizing i-Tree eco-efficiency assessment and real-time feedback mechanisms.China’s urban tree management is in its nascent stages,and there is an urgent need for the development of urban green space.By adopting the refined management assessment methodologies employed for urban trees in Oxford,UK,it is possible to enhance the ecological value of urban trees,which represent a significant green resource within cities,and contribute to the creation of more livable urban spaces. 展开更多
关键词 Oxford Urban tree management i-Tree eco-efficiency assessment INSIGHT REFERENCE
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Eco-efficiency evaluation of symbiotic network for environmental governance PPP projects
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作者 REN Zhi-tao MA Jing-lu +2 位作者 ZHAI Feng-xia WANG Lin LIAN Chen 《Ecological Economy》 2023年第3期244-256,共13页
Under the goal of "double carbon " strategy,the government and enterprises collaborate to form an efficient environmental governance symbiosis network to reduce pollution and carbon.Based on the panel data o... Under the goal of "double carbon " strategy,the government and enterprises collaborate to form an efficient environmental governance symbiosis network to reduce pollution and carbon.Based on the panel data of 30 provinces,the static and dynamic eco-efficiency of the symbiotic network of environmental governance PPP projects are measured by using the SBM model and Malmquist index considering the super-efficiency of non-expected output.The results show that:(1) 8 provinces,including Hebei,have efficiency values greater than 1;11 provinces,including Liaoning,have organizational technology and management levels conducive to efficiency improvement,and 12 provinces,including Zhejiang,are closest to optimal scale efficiency.(2) Redundancy of energy conservation and environmental protection expenditures,urban environmental infrastructure construction investment and new product development projects,insufficient waste gas treatment capacity,environmental emergencies and carbon emission redundancy are all significant factors affecting eco-efficiency.(3) The dynamic efficiency of 8 provinces,including Fujian,shows a decreasing trend,and the Malmquist index and its decomposition indicate that the utilization rate of environmental governance technology should be improved and environmental resources should be allocated rationally. 展开更多
关键词 symbiotic network eco-efficiency super-efficient SBM Malmquist index
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Assessing agricultural eco-efficiency in Chongqing,2004-2019
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作者 XIONG Yan-ting ZHANG Shan-yi ZHOU Si-jia 《Ecological Economy》 2023年第1期16-26,共11页
Agricultural eco-efficiency is an important indicator to measure the sustainable development and high-quality development of agriculture.Based on the agricultural input-output data of 37 districts(counties)in Chongqin... Agricultural eco-efficiency is an important indicator to measure the sustainable development and high-quality development of agriculture.Based on the agricultural input-output data of 37 districts(counties)in Chongqing from 2004 to 2019,this paper uses the static SBM model and the DDF-BML index method to calculate the agricultural eco-efficiency of each district and county in Chongqing and conduct a comparative analysis.The comprehensive analysis of static and dynamic calculation results shows that the agricultural eco-efficiency of Chongqing is low,the agricultural input-output efficiency of various districts and counties is insufficient,and slack variables are common,so the ability of agricultural sustainable development still needs to be improved.The main sources of agricultural eco-efficiency are the progress of agricultural green technology and the efficiency of agricultural green technology.However,as far as the actual situation of Chongqing is concerned,the efficiency of agricultural green technology shows a downward trend,which has an inhibitory effect on the improvement of agricultural eco-efficiency.Therefore,in the process of agricultural ecological development in the future,Chongqing will focus on improving the efficiency of agricultural green technology as a starting point,implement agricultural technology innovation and promotion,improve the level of farmers’science and technology and culture,and achieve"technology to the countryside,demonstration to households,and application to the country."At the same time,it is necessary to further improve the construction of agricultural and rural infrastructure,and promote the"outward migration"of frontier technologies in agricultural production to radiate agricultural development in surrounding districts and counties. 展开更多
关键词 agricultural eco-efficiency SBM model DDF-GML index Chongqing city
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WoS题录Keywords字段关键词频度统计程序设计与实现 被引量:1
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作者 朱玉强 《情报探索》 2015年第6期86-89,共4页
使用Visual Basic编程,采用正则表达式批量提取由Web of Science导出的Bib Tex题录中所有Keywords字段关键词,按需合并所得关键词的同义词、近义词及词形变化词,然后将出现频度的统计数据写入Excel表,并编制Excel宏自动生成折线图,实现... 使用Visual Basic编程,采用正则表达式批量提取由Web of Science导出的Bib Tex题录中所有Keywords字段关键词,按需合并所得关键词的同义词、近义词及词形变化词,然后将出现频度的统计数据写入Excel表,并编制Excel宏自动生成折线图,实现关键词分布的简单可视化。情报工作者后续可借助Excel功能对该程序生成的Excel表执行复杂的数据组合分析,以提高工作效率。 展开更多
关键词 Web of Science(WoS) 关键词 词频统计 Excel BibTex Visual Basic(VB)
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Comparative Analysis on Eco-Efficiency of Arable Land Ecological Footprint in Hubei 被引量:7
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作者 CHENG Bihai WANG Qing LIU Jianxing 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期1052-1058,共7页
This paper uses the ecological footprint model to make comparison of the eco-efficiency of arable land ecological footprint in different years in Hubei Province, and makes comparison of that in Hubei and some countrie... This paper uses the ecological footprint model to make comparison of the eco-efficiency of arable land ecological footprint in different years in Hubei Province, and makes comparison of that in Hubei and some countries. The results indicate that, since 1965, the eco-efficiency of arable land ecological footprint in Hubei has been improved year by year. However, the efficiency of arable land ecological footprint, compared with some other areas in the world, is much lower. In 1965, average eco-efficiency of world arable land ecological footprint is 3 421 US dollar/hm^2 while that of Hubei Province is 134 US dollar/hm^2, about 1/26 of the world's average level. The eco-efficiency of arable land ecological footprint for 2003 in Hubei Province, however, has become about 1/9 of the world's average level for the same year. Finally the author puts forward the ways to raise the eco-efficiency of arable land ecological footprint. 展开更多
关键词 arable land ecological footprint eco-efficiency Hubei Province
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Research on Indicator System of Regional Eco-efficiency:A Case Study of Chengyang District 被引量:4
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作者 Zhou Zhenfeng1,2,Sun Lei2,Sun Yinglan2 1.College of Resources&Environment,Laiyang Agricultural College,Qingdao,Shandong 266109,China 2.School of Environmental Science and Engineering,Ocean University of China,Qingdao,Shandong 266003,China 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第4期54-58,共5页
Eco-efficiency is a valuable tool for managing and solving issues involving resource consumption and pollution emission in current production processes.Despite the popularity of the term"eco-efficiency"in bu... Eco-efficiency is a valuable tool for managing and solving issues involving resource consumption and pollution emission in current production processes.Despite the popularity of the term"eco-efficiency"in business,limited attention has been paid to measuring and reporting regional eco-efficiency for local government policy makers.Based on the concept and method of eco-efficiency,an indicator system of regional eco-efficiency is established in this study.The indicator system comprises 22 indicators,which are divided in to three categories including socio-economic development,resources consumption, environmental pressure.As a promising statistical technique, principle component analysis is used to set the weight of indicators which attempts to calculate the eco-efficiency indices of Qingdao's Chengyang District.The results show that the eco-efficiency of Chengyang District has clearly improved 35.1% with small fluctuation from 1995 to 2003.Socio-economic development index and resources consumption index also represent obvious increasing trends.The correlation coefficient between soci-economic development index and resources consumption index is 0.979,which means the social progress and economic growth of Chengyang District depend on an extravagant consumption of resources.The environmental pressure index increased slowly before 1997 and declined gradually after 1997,due to more attention being paid to environmental protection by local government in recent years.Chengyang District still keeps the traditional economic development mode with a high consumption and high production,so the emphases of future development should put on improving the improving the efficient use of natural resources and promoting environmental management sustainability.The results show that the indicators system of regional eco-efficiency is a promising method to quantitatively evaluate resources and environmental efficiency and provide an effective decision-making support for local governments. 展开更多
关键词 REGIONAL eco-efficiency INDICATOR system Ecoefficiency Synthetic Index (ESI) PRINCIPLE Component Analysis (PCA)
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An improved algorithm for weighting keywords in web documents 被引量:1
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作者 孙双 贺樑 +1 位作者 杨静 顾君忠 《Journal of Shanghai University(English Edition)》 CAS 2008年第3期235-239,共5页
In this paper, an improved algorithm, web-based keyword weight algorithm (WKWA), is presented to weight keywords in web documents. WKWA takes into account representation features of web documents and advantages of t... In this paper, an improved algorithm, web-based keyword weight algorithm (WKWA), is presented to weight keywords in web documents. WKWA takes into account representation features of web documents and advantages of the TF*IDF, TFC and ITC algorithms in order to make it more appropriate for web documents. Meanwhile, the presented algorithm is applied to improved vector space model (IVSM). A real system has been implemented for calculating semantic similarities of web documents. Four experiments have been carried out. They are keyword weight calculation, feature item selection, semantic similarity calculation, and WKWA time performance. The results demonstrate accuracy of keyword weight, and semantic similarity is improved. 展开更多
关键词 improved vector space model (IVSM) representation feature feature item keyword weight semantic similarity
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Lattice-Based Searchable Encryption Scheme against Inside Keywords Guessing Attack 被引量:3
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作者 Xiaoling Yu Chungen Xu +1 位作者 Lei Xu Yuntao Wang 《Computers, Materials & Continua》 SCIE EI 2020年第8期1107-1125,共19页
To save the local storage,users store the data on the cloud server who offers convenient internet services.To guarantee the data privacy,users encrypt the data before uploading them into the cloud server.Since encrypt... To save the local storage,users store the data on the cloud server who offers convenient internet services.To guarantee the data privacy,users encrypt the data before uploading them into the cloud server.Since encryption can reduce the data availability,public-key encryption with keyword search(PEKS)is developed to achieve the retrieval of the encrypted data without decrypting them.However,most PEKS schemes cannot resist quantum computing attack,because the corresponding hardness assumptions are some number theory problems that can be solved efficiently under quantum computers.Besides,the traditional PEKS schemes have an inherent security issue that they cannot resist inside keywords guessing attack(KGA).In this attack,a malicious server can guess the keywords encapsulated in the search token by computing the ciphertext of keywords exhaustively and performing the test between the token and the ciphertext of keywords.In the paper,we propose a lattice-based PEKS scheme that can resist quantum computing attacks.To resist inside KGA,this scheme adopts a lattice-based signature technique into the encryption of keywords to prevent the malicious server from forging a valid ciphertext.Finally,some simulation experiments are conducted to demonstrate the performance of the proposed scheme and some comparison results are further shown with respect to other searchable schemes. 展开更多
关键词 Searchable encryption lattice assumption inside keywords guessing attack post-quantum secure
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Agricultural Eco-efficiency Evaluation in Anhui Province: An Empirical Analysis Based on DEA Method 被引量:1
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作者 Zunyi CHEN 《Asian Agricultural Research》 2013年第4期79-82,共4页
According to the eco-efficiency theory, combined with agricultural production characteristics, I point out the environmental impact and substance energy consumption characteristics of agricultural production. Based on... According to the eco-efficiency theory, combined with agricultural production characteristics, I point out the environmental impact and substance energy consumption characteristics of agricultural production. Based on this, I establish the eco-efficiency evaluation indicator system for agricultural production, and conduct a comprehensive analysis on the agricultural eco-efficiency of 17 prefecture-level cities in Anhui Province, using data envelopment analysis method. 展开更多
关键词 AGRICULTURE eco-efficiency DATA Envelopment Analys
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Improved Research on Fuzzy Search over Encrypted Cloud Data Based on Keywords
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作者 Ping Zhang Jianzhong Wang 《Journal of Computer and Communications》 2015年第9期90-98,共9页
A search strategy over encrypted cloud data based on keywords has been improved and has presented a method using different strategies on the client and the server to improve the search efficiency in this paper. The cl... A search strategy over encrypted cloud data based on keywords has been improved and has presented a method using different strategies on the client and the server to improve the search efficiency in this paper. The client uses the Chinese and English to achieve the synonym construction of the keywords, the establishment of the fuzzy-syllable words and synonyms set of keywords and the implementation of fuzzy search strategy over the encryption of cloud data based on keywords. The server side through the analysis of the user’s query request provides keywords for users to choose and topic words and secondary words are picked out. System will match topic words with historical inquiry in time order, and then the new query result of the request is directly gained. The analysis of the simulation experiment shows that the fuzzy search strategy can make better use of historical results on the basis of privacy protection for the realization of efficient data search, saving the search time and improving the efficiency of search. 展开更多
关键词 CLOUD Data FUZZY SEARCH keywords SYNONYMS Searchable ENCRYPTION
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Problems and Countermeasures in the Keywords of Academic Papers
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作者 WANG Fengnian 《Journalism and Mass Communication》 2019年第1期26-32,共7页
Keywords with the retrieval value clearly show the main contents, enhance the influence of academic periodicals, highlight specific information, and generalize information, but because of the ignorance of the value of... Keywords with the retrieval value clearly show the main contents, enhance the influence of academic periodicals, highlight specific information, and generalize information, but because of the ignorance of the value of keywords from some authors and editors, the lack of canonical guidance, and limitations of the editorial knowledge structure, there are some problems concerning keywords in academic papers, such as papers containing too many or too few keywords, or keywords being used in a way that is too general or colloquial. According to academic principle, accurate principle, logical principle, comprehensive principle, it is imperative to discuss how to choose keywords properly. 展开更多
关键词 keywords ACADEMIC PAPERS SELECTION CRITERIA of keywords COUNTERMEASURES of keywords
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Keywords Index
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《Cell Research》 SCIE CAS CSCD 2006年第12期979-982,983,共5页
关键词 GENE keywords Index CELL
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KEYWORDS INDEX(2006;Volume 8)
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《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第6期761-763,共3页
关键词 429 555 GENE Volume 8 keywords INDEX
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炭专业文献中的关键词(Keywords for carbons)——技术方法(Techniques)
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作者 李峰 王茂章 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2008年第1期50-50,共1页
关键词 电子 轻子 TECHNIQUES keywords for carbons
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炭专业文献中的关键词(Keywords for carbons)——炭的类型(Tpyes of carbon)
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作者 李峰 王茂章 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2008年第1期94-94,共1页
关键词 GRAPHITE keywords for carbons Tpyes of carbon
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炭专业文献中的关键词(Keywords for carbons)——制备和过程(Preparation and processing)
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作者 李峰 王茂章 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2008年第1期85-85,共1页
关键词 keywords for carbons Preparation and processing
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炭专业文献中的关键词(Keywords for carbons)—制备和过程(Preparation and processing)
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作者 李峰 王茂章 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2006年第1期42-42,共1页
关键词 keywords for carbons Preparation and processing
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炭专业文献中的关键词(Keywords for carbons)—性质和现象(Properties and phenomend)
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作者 李峰 王茂章 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2005年第4期323-323,共1页
关键词 keywords for carbons Properties and phenomend
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炭专业文献中的关键词(Keywords for carbons)—炭的类型(Tpyes of carbon)
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作者 李峰 王茂章 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2005年第4期316-316,共1页
关键词 GRAPHITE 中间相 金相相组成 Tpyes of carbon keywords for carbons
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