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Sonic hedgehog signaling during nervous system development 被引量:1
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作者 Qin Yang Peng Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第7期782-785,共4页
The Hedgehog signaling pathway plays a key role in embryonic development and organ formation. Sonic hedgehog signaling participates in nervous system development, regulates proliferation and differentiation of neural ... The Hedgehog signaling pathway plays a key role in embryonic development and organ formation. Sonic hedgehog signaling participates in nervous system development, regulates proliferation and differentiation of neural stem cells, controls growth and targeting of axons, and contributes to specialization of oligodendrocytes. For further studies of the Sonic hedgehog signaling pathway and for the development of new drugs in the treatment of nervous system diseases, it is beneficial to understand these mechanisms. 展开更多
关键词 developMENT nervous system REVIEW Sonic hedgehog
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DPOI: Distributed Software System Development Platform for Ocean Information Service
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作者 GUO Zhongwen HU Keyong +1 位作者 JIANG Yongguo SUN Zhaosui 《Journal of Ocean University of China》 SCIE CAS 2015年第1期65-74,共10页
Ocean information management is of great importance as it has been employed in many areas of ocean science and technology. However, the developments of Ocean Information Systems(OISs) often suffer from low efficiency ... Ocean information management is of great importance as it has been employed in many areas of ocean science and technology. However, the developments of Ocean Information Systems(OISs) often suffer from low efficiency because of repetitive work and continuous modifications caused by dynamic requirements. In this paper, the basic requirements of OISs are analyzed first, and then a novel platform DPOI is proposed to improve development efficiency and enhance software quality of OISs by providing off-the-shelf resources. In the platform, the OIS is decomposed hierarchically into a set of modules, which can be reused in different system developments. These modules include the acquisition middleware and data loader that collect data from instruments and files respectively, the database that stores data consistently, the components that support fast application generation, the web services that make the data from distributed sources syntactical by use of predefined schemas and the configuration toolkit that enables software customization. With the assistance of the development platform, the software development needs no programming and the development procedure is thus accelerated greatly. We have applied the development platform in practical developments and evaluated its efficiency in several development practices and different development approaches. The results show that DPOI significantly improves development efficiency and software quality. 展开更多
关键词 系统开发平台 海洋科学 分布式软件 信息服务 应用开发平台 海洋信息系统 软件质量 开发效率
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The Curriculum System Development of Sightseeing Agriculture Major Based on Work Flow
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作者 Sujuan CHEN Guoyuan CHEN Chengzhong WANG 《Asian Agricultural Research》 2014年第12期96-97,100,共3页
From the position setting of sightseeing agriculture businesses and ability analysis,this paper analyzes the career action field based on training objectives of sightseeing agriculture major and determines the typical... From the position setting of sightseeing agriculture businesses and ability analysis,this paper analyzes the career action field based on training objectives of sightseeing agriculture major and determines the typical tasks and career action field. According to the major teaching design of career action field,this paper introduces the systematic curriculum system of sightseeing agriculture major based on work flow. 展开更多
关键词 SIGHTSEEING AGRICULTURE CURRICULUM system developm
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Influencing Factors on Farming System Development in Shandong Province 被引量:1
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作者 LIU Yan1,NING Tang-yuan1,ZHOU Xun-bo1,2 1.State Key Laboratory of Crop Biology,Shandong Key Laboratory of Crop Biology,Shandong Agricultural University,Taian 271018,China 2.Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 《Asian Agricultural Research》 2010年第10期60-64,共5页
The developmental situation of the farming system in Shandong Province is introduced.At present,Shandong Province is at the semi-intensive,semi-commercial and semi-sufficiency level of farming system.Eastern coast and... The developmental situation of the farming system in Shandong Province is introduced.At present,Shandong Province is at the semi-intensive,semi-commercial and semi-sufficiency level of farming system.Eastern coast and central Shandong agricultural zones are moving in the direction of modern farming system,having formed a preliminary new pattern of the coordinated development of grain,feedstuff,economic and other crops.Influencing factors on the development of farming system in Shandong Province is analyzed,which are agricultural production condition and input level,population and food,policy measures,development of natural resources and regions,agricultural industrialization and urbanization level,and scientific and technological level.Total population will be within 100 million at the year 2020;per capita annual share of grain will be 475 kilograms;and there is great pressure on grain production.Therefore,we must change the pattern of agricultural development and accelerate the establishment of modern farming system.Agricultural machinery,water conservancy projects,and chemical fertilizer application have greatly affected the development of farming system.Improvement of production conditions has promoted the adjustment of agricultural structure,increased the planting ratio of winter wheat-summer maize,and improved multiple-cropping index.Development of agricultural industrialization has promoted the transfer of rural labor force and the establishment of modern farming system;while the unbalanced development of cities has restricted the establishment of modern farming system.Therefore,the appropriate policy,scientific and rational regional distribution,and advanced science and technology can help to set up the modern farming system in Shandong Province. 展开更多
关键词 SHANDONG PROVINCE STRUCTURE adjustment REGIONAL DE
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The Olig family affects central nervous system development and disease 被引量:5
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作者 Botao Tan Jing Yu +3 位作者 Ying Yin Gongwei Jia Wei Jiang Lehua Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第3期329-336,共8页
Neural cell differentiation and maturation is a critical step during central nervous system devel-opment. The oligodendrocyte transcription family (Olig family) is known to be an important factor in regulating neura... Neural cell differentiation and maturation is a critical step during central nervous system devel-opment. The oligodendrocyte transcription family (Olig family) is known to be an important factor in regulating neural cell differentiation. Because of this, the Olig family also affects acute and chronic central nervous system diseases, including brain injury, multiple sclerosis, and even gliomas. Improved understanding about the functions of the Olig family in central nervous system development and disease will greatly aid novel breakthroughs in central nervous system diseases. This review investigates the role of the Olig family in central nervous system develop- ment and related diseases. 展开更多
关键词 nerve regeneration brain injury spinal cord injury review Olig family oligodendro-cytes ASTROCYTES central nervous system disease DEMYELINATION development DIFFERENTIATION NSFCgrant neural regeneration
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Distributed Generation Influence on Power Distribution System Development in Poland
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作者 Maksymilian Przygrodzki 《Journal of Energy and Power Engineering》 2012年第9期1509-1514,共6页
关键词 分布式发电 配电系统 波兰 电力部门 经济效率 输电网 消费者 投资者
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Rethinking Enterprise Architecture for Sustainable Energy System Development
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作者 Jovita Vasauskaite Asif Qumer Gill 《Journal of Electronic Science and Technology》 CAS CSCD 2015年第3期212-220,共9页
The development of a sustainable energy system throughout an enterprise is a complex task, which requires an agile holistic approach. Such an approach needs to include a variety of objectives including energy strategy... The development of a sustainable energy system throughout an enterprise is a complex task, which requires an agile holistic approach. Such an approach needs to include a variety of objectives including energy strategy formation and strategic decision-making, which are directly related to the analysis and management of the main areas of sustainable development: The economic, technological, environmental, and social. These multidimensional requirements of sustainability are often difficult to achieve within the enterprise, because these aspects are interrelated and influenced by various internal and external environment factors. This paper first reviews the main challenges for an energy system, and then demonstrates how a strategic agile enterprise architecture driven approach could effectively guide the sustainable energy system development. The study presented in this paper provides a holistic approach that contributes to the advancement and usage of literature dealing with issues of sustainable energy system development and agile enterprise architecture, which has not been discussed before to any great extent. 展开更多
关键词 developMENT energy system enterprise architecture INDUSTRY sustainability.
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Expression of vimentin and glial fibrillary acidic protein in central nervous system development of rats 被引量:1
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作者 Hua Luo Xiao-Qiong Wu +4 位作者 Min Zhao Qiong Wang Geng-Pan Jiang Wei-Jun Cai Ming-Ying Luo 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第12期1185-1189,共5页
Objective: To investigate the distribution and contents of vimentin(Vim) and glial fibrillary acidic protein(GFAP) immunoreactivities in the central nervous system(CNS)of normal newborn, adult and aged rats.Methods: I... Objective: To investigate the distribution and contents of vimentin(Vim) and glial fibrillary acidic protein(GFAP) immunoreactivities in the central nervous system(CNS)of normal newborn, adult and aged rats.Methods: In this study, thirty healthy and normal Sprague–Dawley rats were simply classified into three groups: Newborn(7 days aged), adult(5 months aged) and aged(24 months aged) rats. Brains and spinal cord were dissected and cut into frozen sections. The expression of Vim and GFAP in CNS were detected by confocal immunofluorescence.Results: In each group, Vim was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was highest in neuron-like cell of newborn rats, while Vim was mainly expressed in cell bodies in adult and aged rats. GFAP was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was in astrocytes of aged rats. In the third ventricle, Vim was detected in all groups, and only observed in neuron-like cells of newborn. Meanwhile, the GFAP expression showed no significant differences between adult and aged rats in this region. The co-localization of Vim and GFAP were mainly observed in hippocampus and cerebral cortex of newborn,but this co-localization was found in the third ventricle of the rats in all groups.Conclusion: Our data demonstrate for the first time that the expression of Vim and GFAP in the rat's CNS during development. This data may provide a foundation for the further mechanistic studies of these two main intermediate filaments during development of CNS. 展开更多
关键词 developMENT VIMENTIN Glial fibrillary acidic protein Central nervous system
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Conventional Geothermal Systems and Unconventional Geothermal Developments: An Overview
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作者 Maryam Khodayar Sveinbjörn Björnsson 《Open Journal of Geology》 CAS 2024年第2期196-246,共51页
This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal syste... This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal systems have the heat, permeability and fluid, requiring only drilling down to °C, normal heat flow or decaying radiogenic granite as heat sources, and used in district heating. Medium-temperature (MT) 100°C - 190°C, and high-temperature (HT) 190°C - 374°C resources are mostly at plate boundaries, with volcanic intrusive heat source, used mostly for electricity generation. Single well capacities are °C - 500°C) and a range of depths (1 m to 20 Km), but lack permeability or fluid, thus requiring stimulations for heat extraction by conduction. HVAC is 1 - 2 m deep and shallow geothermal down to 500 m in wells, both capturing °C, with °C are either advanced by geothermal developers at <7 Km depth (Enhanced Geothermal Systems (EGS), drilling below brittle-ductile transition zones and under geothermal fields), or by the Oil & Gas industry (Advanced Geothermal Systems, heat recovery from hydrocarbon wells or reservoirs, Superhot Rock Geothermal, and millimeter-wave drilling down to 20 Km). Their primary aim is electricity generation, relying on closed-loops, but EGS uses fractures for heat exchange with earthquake risks during fracking. Unconventional approaches could be everywhere, with shallow geothermal already functional. The deeper and hotter unconventional alternatives are still experimental, overcoming costs and technological challenges to become fully commercial. Meanwhile, the conventional geothermal resources remain the most proven opportunities for investments and development. 展开更多
关键词 Conventional Geothermal systems Unconventional Geothermal developments Shallow and Deep Closed-Loops Enhanced Geothermal systems Supercritical and Millimeter-Wave Drilling
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Comparative Analysis and Fuzzy Selection of Information System Development Approach 被引量:1
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作者 CHEN Xiaohong LIU Mai YASUHIKO Takahara 《Systems Science and Systems Engineering》 CSCD 1998年第1期121-129,共9页
ComparativeAnalysisandFuzzySelectionofInformationSystemDevelopmentApproach⒇CHENXiaohong*LIUMai*YASUHIKOTakah... ComparativeAnalysisandFuzzySelectionofInformationSystemDevelopmentApproach⒇CHENXiaohong*LIUMai*YASUHIKOTakahara***ColegeofBus... 展开更多
关键词 information system development approach(ISDA) factor analysis fuzzy selection fuzzy syntheticdiscrimination MODEL
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Research and Development on NC System of Gear-hobbing Machine based on Zero-programming Technology
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作者 HUANG He LIU Fu-hua +2 位作者 FENG Guo-qun LIU Liang CHEN Qing-lin 《International Journal of Plant Engineering and Management》 2016年第4期241-254,共14页
By the analysis of roller gear processing technology, combining with gear meshing mechanism and motion relationship, models for rolling gear machining parameter and zero-programming are established. In this paper, the... By the analysis of roller gear processing technology, combining with gear meshing mechanism and motion relationship, models for rolling gear machining parameter and zero-programming are established. In this paper, the automatic generation technology of NC program for CNC gear machining process has been studied and the zero-programming system architecture of open CNC gear-hobbing machine has been presented. In the design and development of the system, human computer interaction, programming algorithm and the design of each function module have bean done. Application test shows that the expected design requirements have been achieved. 展开更多
关键词 CNC gear-hobbing machine zero-programming open CNC system development
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Discussion on the Index System of Intensive Land Use Evaluation in Development Area 被引量:7
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作者 LIU Xiang-dong1,GAO Jie2 1.School of Land Science and Technology,China University of Geosciences,Beijing 100083,China 2.Weida Real Estate Evaluation Corporation of Henan Province,Luoyang 471000,China 《Asian Agricultural Research》 2011年第2期91-96,100,共7页
The establishment of evaluation index system is the key to the evaluation of intensive land use.On the basis of expounding connotation,characteristics and the principle of establishing evaluation index system,and as f... The establishment of evaluation index system is the key to the evaluation of intensive land use.On the basis of expounding connotation,characteristics and the principle of establishing evaluation index system,and as for the problems existing in Evaluation Regulation(Trial)of Intensive Land Use in Development Area,regarding the evaluation index system of intensive land use in the development area,in the light of the connotation of intensive land use in development area,coupled with the practical situation of the land use in China's development area,after referring to the research achievements of domestic and abroad scholars,some suggestions are put forward in order to improve and perfect the evaluation index system of intensive land us in development area. 展开更多
关键词 INTENSIVE LAND USE EVALUATION INDEX system develop
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Global Memory Net and the development of digital image information management system: Experience and practice 被引量:4
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作者 ZHANG Sheng-qiang CHEN Ching-chih 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1216-1220,共5页
Global Memory Net (GMNet) is intended to be an effective gateway to the world cultural, historical, and heritage image collections from selected academic educational and research partners in the world. Much of these u... Global Memory Net (GMNet) is intended to be an effective gateway to the world cultural, historical, and heritage image collections from selected academic educational and research partners in the world. Much of these unique collections of great value to education and research are not currently accessible due to distance, form, and technical barriers. This project is to find new ways to enable users to access and exploit these significant research collections via global network. As GMNet is ending its first 5-year phase in October 2005, it has contributed substantially to the community building in digital library development by ac- commodating numerous collaborators and technical staff from various parts of the world to spend 3 to 5 months as a full-member of the GMNet team in Boston. They have come from different parts of China—such as Sichuan, Hainan, Shanghai and Xi’an; Croatia; and Hanoi, Vietnam. In addition to contribute to the overall system development and enhancement of system function- alities, they have brought valuable sample image collections of their own institutions/countries, and actually developed prototype collections as a part of GMNet. This paper describes the exciting and productive experience of the first of this visiting research group in developing the GMNet’s Version 2.0 PHP-based system under Prof. Chen’s overall supervision. It also describes both the system’s technical level structure—user/Web-based application/data, and complex functionalities with multi-collection, multi-lingual, multi-modal searching capabilities; system management capabilities; as well as provisions for user uploads and retrieval for our own projects. This Version 2.0 system is built on the Linux/Apache/PHP/MySQL platform. What is described in this paper is an actual case which has formed a base for further new development by others in the research group. It demonstrates fully the value of the synergistic collaboration among global partners for universal digital library development. More information can be found in http://www.memorynet.org/. 展开更多
关键词 数字图书馆 数字图象信息 管理系统 网络存储 搜索参数
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STUDY ON FUNCTION OF COMPONENTS OF DY NAMIC SYSTEM OF TOURISM DEVELOPMENT IN DEVELOPED REGION---A Case Study of Foshan in Guangdong Province 被引量:1
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作者 ZHONGYun PENGHua 《Chinese Geographical Science》 SCIE CSCD 2002年第3期226-232,共7页
In the forming of the Dynamic System of Tourism Development (DSTD)in developed regions from the view of supply side,the Delphi Method and the Analytical Hierarchy Process(AHP)are used to count the weight of each compo... In the forming of the Dynamic System of Tourism Development (DSTD)in developed regions from the view of supply side,the Delphi Method and the Analytical Hierarchy Process(AHP)are used to count the weight of each component of the DSTD.It has been fou nd that the attraction subsystem is t he most important one of the three subsystems at the first hierarchical level of DSTD,which means that tourist attractions are always the principal factors for regional tourism development,even in develo ped regions.But it is also noteworth y that the significance of the attraction subsystem is not dominant in the DSTD.At the sec ond hierarchical level,the physica l attraction subsystem rank No.1,while the weight of the non-physical attraction subsystem is just a little larger t han the weight of the hardware subsystem and that of software subsystem.And the weights of the three components in the medium subsystem are similar.The top 3factors at the third hierarchical level are scenic spot,location and regional econ omic impact.The result verifies the conclusions of qualitative analysis,which depends on the market research and the study of historical date,that the most imp ortant compo-nent of the DSTD in Foshan is the impact of the developed economy.Knowing t he weight of each component of the DST D can be helpful to make out the most use ful force,furthermore to determine the future orientation for regional tourismdevelop-ment. 展开更多
关键词 发展地区 AHP 旅游事业 广东 佛山市 解析谱系法
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Indicator system and evaluation framework for sustainable development 被引量:3
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作者 ZHAO Jing\|zhu\+1, Johannes Baptist Opschoor\+2 (1. Department of Systems Ecology, Research Center for Eco\|Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 2. Economics Faculty, Free University, De Boelelaan 1105, 1081 HV Am 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第4期492-497,共6页
An indicator system of sustainable development was established and an evaluation framework for sustainable development was drawn in this study.
关键词 sustainable development indicator system evaluation framework
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(Dis)Economies of Scale in Business Software Systems Development and Enhancement Projects 被引量:1
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作者 Beata Czamacka-Chrobot 《Computer Technology and Application》 2012年第1期88-97,共10页
关键词 软件系统开发 规模经济 软件工程 DIS 商业 量表 单位成本 软件开发
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Construction of the Classification and Grading Index System of Cultivated Land Based on the Viewpoint of Sustainable Development 被引量:1
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作者 CUI Qian, WU Yu-ling, LI Qing College of Urban and Environmental Sciences, Huazhong Normal University, Wuhan 430079, China 《Asian Agricultural Research》 2010年第9期45-48,52,共5页
In order to objectively and reasonably evaluate the actual and potential value of cultivated land, both social and ecological values are introduced into the classification and grading index system of cultivated land b... In order to objectively and reasonably evaluate the actual and potential value of cultivated land, both social and ecological values are introduced into the classification and grading index system of cultivated land based on the viewpoint of sustainable development, after considering the natural and economic values of cultivated land. Index system construction of the sustainable utilization of cultivated land should follow the principles of economic viability, social acceptability, and ecological protection. Classification of cultivated land should take into account the soil fertility of cultivated land. Then, grading of cultivated land is carried out from the practical productivity (or potential productivity) of cultivated land. According to the existing classification index system of cultivated land, the soil, natural and environmental factors in plains, mountains and hills are mainly modified in the classification index system of cultivated land. And index systems for the cultivated land classification in plains, mountains and hills are set up. The grading index system of cultivated land is established based on the economic viability (economic value), social acceptability (social value) and protection of cultivated land (ecological value). Quantitative expression of cultivated land grading index is also carried out. 展开更多
关键词 CLASSIFICATION and GRADING of CULTIVATED land INDE
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Development Mechanism of Urban System in Rapidly Changing Period in China 被引量:1
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作者 DU Guoqing 《Chinese Geographical Science》 SCIE CSCD 2007年第1期10-18,共9页
The purpose of this research is to investigate the socio-economic development mechanism of China’s urban system in terms of spatial structure and its change. Totally 246 cities from 340 designated cities in 1985, and... The purpose of this research is to investigate the socio-economic development mechanism of China’s urban system in terms of spatial structure and its change. Totally 246 cities from 340 designated cities in 1985, and 488 from 640 designated cities in 1995 are selected as sample cities. And 22 attributes concerning urban features are analyzed to clarify the socio-economic characteristics and their changes in the urban system. Finally, the primary development factors are verified with the relationship of spatial structure and socio-economic characteristics. In conclusion, the socio-economic changes occurred more extremely than spatial structure changes. Furthermore, foreign investment be- came a major power for the development of China’s urban system in the period of 1985–1995. 展开更多
关键词 城市体系 发展机制 社会-经济发展 外资投资 中国 快速转型期
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Developing a quantitative index system for assessing sustainable forestry management in Heilongjiang Province,China: a case study 被引量:4
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作者 Jin-shan Yang Feng-you Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第3期611-619,共9页
In this study, we developed a comprehensive index system for forestry sustainability of Heilongjiang Province, which includes forest resources sustainability,sustainable economic development, sustainable social develo... In this study, we developed a comprehensive index system for forestry sustainability of Heilongjiang Province, which includes forest resources sustainability,sustainable economic development, sustainable social development and sustainable advancement in science and technology. Based on this system and the regional forest development, we further evaluated the sustainability of Heilongjiang Province for year 2008-2013. The results show that even though the regional forestry has been preliminarily on the track of sustainable development, it is fragile. Four indicators, e.g. soil and water retention rate,forest stand growth(per unit area), the proportion of national investment and the annual carbon sequestration have important impact on the sustainability, with a weight of 39.0 % in all the indicators. We also analyzed the factors hindering the sustainable development. It turns out that soil and water retention rate, forest stand growth(per unit area),the proportion of science and technology funds, per capita GDP and the proportion of the tertiary industry production are the main factors hindering regional sustainable development, which accounts for 50.94 % of the total obstacle degrees in the system. At last, we discussed how to promote the regional sustainable development from the perspectives of forest resources sustainability, economic development sustainability, society development sustainability and the sustainable advancement of science and technology. 展开更多
关键词 Regional forestry Sustainable development Index system Empirical analysis
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Technological system for sustainable development of Chinese agriculture 被引量:2
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作者 Zhang Renwu Ji Wenying Zhang Tong (Agro-Environmental Protection Institute , Tianjin 300191, China) Sun Hongliang (Institute of Crop Breeding and Cultivation, Chinese Academy of Agricultural Sciences, Beijing 100081, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第4期471-477,共7页
Along with the rapid development of economy, Chinese agriculture with a long history is facingthe challenge from environment. So, the technological system for sustainable development of agriculturewith Chinese charact... Along with the rapid development of economy, Chinese agriculture with a long history is facingthe challenge from environment. So, the technological system for sustainable development of agriculturewith Chinese characteristics, which are based on the eco-economic principle, should be establisbed throughusing the approach of system engineering, carrying on the cream of Chinese traditional agricultural tech-niques and adopting modern agricultural techniques. The sustainable development should be realized on thebasis of sound cycles of economy and ecology and coordinated development between environmental protectionand economic growth or exploitation and regeneration of natural resources. 展开更多
关键词 sustainable development technological system ecoeconomy sound circulation.
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