期刊文献+
共找到6,351篇文章
< 1 2 250 >
每页显示 20 50 100
Eco-economic evolution, emergy evaluation and policy options for the sustainable development of Tibet 被引量:13
1
作者 YAN Mao-chao, H. T. Odum ( Commission for Integrated Survey of Natural Resources, Chinese Academy of Sciences, Beijing, China, Center for Environmental Policy, Department of Environmental Engineering Sciences, University of Florida, Gainesville, FL, USA) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第1期1-27,共27页
As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor ec... As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor economics alone can address the problems of our global commons. New measures of wealth, of value, of contributions and production are needed that acknowledge the 'natural capital' and 'ecosystem services' provided from healthy environments. A new interface is now being recognized termed 'eco-economics'. It is an ambitious and necessary attempt to understand the affairs of humanity and nature as a single, interdependent system. New tools are being invested to measure wealth. services and production fairly and equitably. In this report we use systems analysis approach to study the combined ecological-economic system of Tibet We use an alternative measure of value, based on real contributions to system performance, termed EMERGY, spelt with an 'M'. It is an accounting unit of total contributions, direct and indirect. used in generating a product or service. It is a concept derived from understanding whole systems, their interactions and interdependence, and the resources driving and maintaining them. This broader approach will help us to investigate Tibetan resources utilization and potentialities and exchange. Emergy analysis allows comparison and incroporation of environmental costs and benefits with variables of traditional economic costs and benefits to provide a more comprehensive perspective for public policy directives. Through this research, we think: 1) China has made a great effort in making Tibet develop from a closed regional system to a more and more opened regional system which is very important to the sustainable development of Tibet. 2) The increase of economic development and population growth has a close relationship with the total emergy storage and use in transportation. Education in modern science and technology increased the shared emergy of Tibetans to modern science and technology and stimulated the process of matching material and energy imports from outside with local resources. 3) There is great potential to develop hydropower and geothermal reserves that may stimulate not only economic development but also the better use of environment. 4) The better trained population can increase the empower of Tibet eco-economic system. Future development needs all kinds of talent exchanges with the outside system to develop education. 3) Compared with the Tibet economic system, Taiwan economic system is much more competitive. GNP and emergy use are very useful functions for comparing the competitive power of different ecological economic systems. 展开更多
关键词 EMERGY eco-economic evolution sustainable development
下载PDF
Spatio-temporal Evolution and Driving Factors of the High-quality Development of Provincial Tourism in China 被引量:8
2
作者 WANG Xinyue WANG Mengmeng +3 位作者 LU Xuejing GUO Lizhen ZHAO Ruixin JI Ranran 《Chinese Geographical Science》 SCIE CSCD 2022年第5期896-914,共19页
Accelerating the promotion of high-quality development of tourism(HQDT) is of great significance to the sustainable development of tourism. This paper defined the concept of HQDT, and then built an evaluation system f... Accelerating the promotion of high-quality development of tourism(HQDT) is of great significance to the sustainable development of tourism. This paper defined the concept of HQDT, and then built an evaluation system for HQDT measurement to analyze the spatio-temporal evolution characteristics of China’s HQDT based on provincial panel data from 2010 to 2019, using Geodetector to explore the similarities and differences between driving factors of HQDT and tourism development scale(TDS). The results show that:1) Taking the development concepts of innovation, coordination, green, openness and sharing as the guidance, and considering the organic unity of quantity and quality, the evaluation index system of the HQDT consists of six dimensions of economic stability, innovation driving, coordination and linkage, green and sustainability, openness and cooperation, and sharing and harmony, which respectively represent the basis, momentum, means, orientation, direction and purpose of the HQDT;2) The level of China’s HQDT shows an upward trend, presenting the characteristics of eastern region > central region > western region > northeastern region in 2019. The regional differences in China’s HQDT show a downward trend, and the intra-regional differences have replaced the inter-regional differences as the main source of regional differences;3) China’s HQDT shows the characteristics of higher in the east and lower in the west along the Hu line, while the improvement speed of HQDT shows the characteristics of faster in the west and slower in the east, making the decline of east-west differentiation of China’s HQDT and the movement of the gravity center towards southwest;4) Both HQDT and TDS are obviously driven by tourism capital investment and regional consumption. In terms of differences, the HQDT is more driven by government guidance, innovation driving force, and opening up, while the main driving factors of TDS are more biased toward capital elements and hardware facilities, including informatization, tourism resource, traffic, and eco-environment. 展开更多
关键词 high-quality development of tourism(HQDT) spatio-temporal evolution Geodetector tourism development scale(TDS)
下载PDF
Regional Evolution Features and Coordinated Development Strategies for Northeast China 被引量:3
3
作者 MEI Lin XU Xiaopo CHEN Mingxiu 《Chinese Geographical Science》 SCIE CSCD 2006年第4期378-382,共5页
Northeast China, as the most important production base of agriculture, forestry, and livestock-breeding as well as the old industrial base in the whole country, has been playin a key role in the construction and deve... Northeast China, as the most important production base of agriculture, forestry, and livestock-breeding as well as the old industrial base in the whole country, has been playin a key role in the construction and development of China's economy. However, after the policy of reform and open-up was taken in China. the economic development speed and efficiency ofthis area have turned to be evidently lower than those of coastal area and the national average level as well, which is so-called 'Northeast Phenomenon' and 'Neo-Northeast Phenomenon'. In terms of those phenomena, this paper firstly reviews the spatial and temporal features of the regional evolution of this area so as to unveil the profound forming causes of 'Northeast Phenomena' and 'Neo-Northeast Phenomena'. And then the paper makes a further exploration into the status quo of this region and its forming causes by analyzing its economy gross, industrial structure, product structure, regional eco-categories, etc. At the end of the paper, the authors put forward the basic coordinated development strategies for Northeast China. namely we can revitalize this area by means of adjustment of economic structure, regional coordination, planning urban and rural areas as a whole, institutional innovation, etc. 展开更多
关键词 regional evolution spatial-temporal feature coordinated development strategy Northeast China
下载PDF
Application of Pore Evolution and Fracture Development Coupled Models in the Prediction of Reservoir "Sweet Spots" in Tight Sandstones 被引量:3
4
作者 ZHANG Linyan ZHUO Xizhun +3 位作者 MA Licheng CHEN Xiaoshuai SONG Licai ZHOU Xingui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期1051-1052,共2页
The Chang-63 reservoir in the Huaqing area has widely developed tight sandstone "thick sand layers, but not reservoirs characterized by rich in oil", and it is thus necessary to further study its oil and gas enrichm... The Chang-63 reservoir in the Huaqing area has widely developed tight sandstone "thick sand layers, but not reservoirs characterized by rich in oil", and it is thus necessary to further study its oil and gas enrichment law. This study builds porosity and fracture development and evolution models in different deposition environments, through core observation, casting thin section, SEM, porosity and permeability analysis, burial history analysis, and "four-property-relationships" analysis. 展开更多
关键词 Sweet Spots in Tight Sandstones Application of Pore evolution and Fracture development Coupled Models in the Prediction of Reservoir
下载PDF
Spatio-temporal Evolution Characteristics and Driving Mechanism of the New Infrastructure Construction Development Potential in China 被引量:1
5
作者 GU Tianshi ZHANG Peng ZHANG Xujia 《Chinese Geographical Science》 SCIE CSCD 2021年第4期646-658,共13页
With the advent of the era of big data and artificial intelligence, new infrastructure construction(NIC) has attracted the attention of many countries. The development of NIC provides an opportunity to bridge the digi... With the advent of the era of big data and artificial intelligence, new infrastructure construction(NIC) has attracted the attention of many countries. The development of NIC provides an opportunity to bridge the digital divide and narrow the regional gap,providing continuous impetus to further promote economic development. Here, we considered 31 provincial-level administrative units in China(not including Hong Kong, Macao, and Taiwan of China due to data unavailable) and established comprehensive evaluation indicators for the development potential of NIC. Afterward, we used the entropy-weight TOPSIS model to determine the development potential of NIC and analyze its spatio-temporal evolution characteristics. Furthermore, the GeoDetector model was applied to explore the driving mechanism of the NIC development potential. The conclusions were as follows: (1) The Chinese NIC development potential is generally low. The eastern China was the region with the highest development potential year by year, while the development potential in the central China was found to be in an accelerating phase. (2) The evolution of the Chinese NIC development potential’s spatial pattern has been characterized by an inland extension and coastal agglomeration. Moreover, we identified a superior development zone, a rising development zone, an inferior development zone, and a declining development zone. (3) The scope of Chinese NIC development potential agglomeration areas has gradually expanded and its degree has gradually deepened. The range of high-value agglomeration in eastern area gradually expanded and its degree gradually deepened. (4) Investment in innovative talents appears as the core factor affecting the Chinese NIC development potential. Whether acting alone or synergistically with other factors, its promoting effect on Chinese NIC development potential is the strongest. 展开更多
关键词 new infrastructure construction development potential spatio-temporal evolution driving mechanism China
下载PDF
EVOLUTION OF POPULATION, RESOURCES, ENVIRONMENT AND INTEGRATED STRATEGY OF THEIR DEVELOPMENT IN SHANGHAI 被引量:1
6
《Chinese Geographical Science》 SCIE CSCD 2000年第3期11-17,共2页
关键词 PRED RESOURCES ENVIRONMENT AND INTEGRATED STRATEGY OF theIR development IN SHANGHAI evolution OF POPULATION
下载PDF
Evolution of pectin synthesis relevant galacturonosyltransferase gene family and its expression during cotton fiber development 被引量:1
7
作者 FAN Senmiao LIU Aiying +10 位作者 ZOU Xianyan ZHANG Zhen GE Qun GONG Wankui LI Junwen GONG Juwu SHI Yuzhen DENG Xiaoying JIA Tingting YUAN Youlu SHANG Haihong 《Journal of Cotton Research》 2021年第3期239-260,共22页
Background:Pectin is a key substance involved in cell wall development,and the galacturonosyltransferases(GAUTs)gene family is a critical participant in the pectin synthesis pathway.Systematic and comprehensive resear... Background:Pectin is a key substance involved in cell wall development,and the galacturonosyltransferases(GAUTs)gene family is a critical participant in the pectin synthesis pathway.Systematic and comprehensive research on GAUTs has not been performed in cotton.Analysis of the evolution and expression patterns of the GAUT gene family in different cotton species is needed to in crease kno wledge of the functi on of pectin in cotto n fiber development.Results:In this study,we have identified 131 GAUT genes in the genomes of four Gossypium species(G.raimondii,G barbadense,G.hirsutum,and G.arboreum),and classified them as GAUT-A,GAUT-B and GAUT-C,which coding probable galacturonosyltransferases.Among them,the GAUT genes encode proteins GAUT1 to GAUT15.All GAUT proteins except for GAUT7 contai n a con served glycosyl transferase family 8 domain(H-DN-A-SW-S-V-H-T-F).The conserved sequence of GAUT7 is PLN(phospholamban)02769 domain.According to c/s-elemet analysis,GAUT genes transcript levels may be regulated by horm ones such as JA,GA,SA,ABA,Me-JA,and IA A.The evoluti on and transcription patterns of the GAUT gene family in different cotton species and the transcript levels in upland cotton lines with different fiber st「ength were analyzed.Peak transcript level of GhGAUT genes have been observed before 15 DPA.In the six materials with high fiber strength,the transcription of GhGAUT genes were concentrated from 10 to 15 DPA;while the highest transcript levels in low fiber st「ength materials were detected between 5 and 10 DPA.These results lays the foundation for future research on gene function during cotton fiber development.Conclusions:The GAUT gene family may affect cotton fiber development,including fiber elongation and fiber thickening.In the low strength fiber lines,GAUTs mainly participate in fiber elongation,whereas their major effect on cotton with high strength fiber is related to both elongation and thickening. 展开更多
关键词 Cotton fiber development PECTIN Galacturonosyltransferases evolution Transcription patterns
下载PDF
BeiDou Navigation Satellite System Services: the Evolution and Way Ahead
8
作者 LU Jun ZHANG Gong +2 位作者 WANG Huilin LI Gang YANG Yu 《Aerospace China》 2024年第2期3-14,共12页
Since the official operation of the BeiDou Global Navigation Satellite System (BDS-3), it has played a vitalrole in the national economy, national defence and security, and to enhance the people’s productivity and li... Since the official operation of the BeiDou Global Navigation Satellite System (BDS-3), it has played a vitalrole in the national economy, national defence and security, and to enhance the people’s productivity and life. Basedupon the three main characteristics, route design inheritance and development, highly integrated services, and “spiraling”incremental development, this paper introduces the service composition of BeiDou Navigation Satellite System (BDS)and summarizes the evolution of four types of BDS services, that include Positioning, Navigation and Timing (PNT),message communications, navigation augmentation, and international Search and Rescue (SAR). Moreover, the designfeatures and performance of each service are discussed in detail, and the development trend of BDS services is examinedin the light of the latest round of changes in the Global Navigation Satellite System (GNSS). Finally, developmentproposals are proposed, namely, stable operation of the system, enhancement of service performance, and empowermentthrough integration of multiple means. 展开更多
关键词 BDS-3 service evolution development status
下载PDF
Path of Rural Sustainable Development Based on the Evolution and Interaction of Rural Functions:A Case Study of Chongqing Municipality,China
9
作者 DAI Ruilian WANG Cheng WU Xinyue 《Chinese Geographical Science》 SCIE CSCD 2022年第6期1035-1051,共17页
In order to investigate the evolutionary characteristics of rural functions and their interaction,37 districts and counties in Chongqing,China are used as research objects to measure the level of rural functions and a... In order to investigate the evolutionary characteristics of rural functions and their interaction,37 districts and counties in Chongqing,China are used as research objects to measure the level of rural functions and analyze the interaction between rural functions using entropy value method and spatial autocorrelation method.The results show that from 2009 to 2019,the three main functions of production,living and ecology in Chongqing’s villages have been greatly enhanced,especially the production function.On the whole,the production and living functions are stronger in the western part,while the ecological functions are significant in the eastern and southern parts of Chongqing,with some differences in local spatial characteristics.This finding is consistent with the regional economic and social development of Chongqing.In addition,the interaction between rural functions is also evident.In general,production and living functions are mainly expressed in synergistic relationships.Ecological and production functions,including ecological and subsistence functions,mainly present a trade-off relationship.The interactions between rural functions also show clear spatial and temporal differences.In addition,different regions have different comparative advantage functions,and in this study,the counties of Chongqing are classified into four types.Policy makers are advised to adopt different measures according to the different types to promote sustainable rural development by coordinating the’production-living-ecological’functions of rural areas.This study reveals the spatio-temporal evolution of rural functions and the interaction between rural functions,which can provide theoretical support and practical reference for rural revitalisation and sustainable development. 展开更多
关键词 synergy and trade-off production-living-ecological function Chongqing Municipality spatio-temporal evolution rural sustainable development
下载PDF
Evolution and prospect of China's rural development policy: A policy text analysis of the No.1 Central Documents
10
作者 WANG Qiang 《Ecological Economy》 2018年第4期268-281,共14页
By combing 20 documents of the Central Committee on the historical evolution of rural development policies since 1982, we hold that historical evolution has undergone reforms, adjustments, modernization developments a... By combing 20 documents of the Central Committee on the historical evolution of rural development policies since 1982, we hold that historical evolution has undergone reforms, adjustments, modernization developments and new ideas, and the path of reform experienced economic recovery, industrial nurturing agriculture, agriculture modernization and rural revitalization. The study found that: farmers' income has always been the focus of attention; agricultural production has shifted from total demand to green ecology; urban and rural resource elements are not well-organized, resulting in internal contradictions. The implementation of the rural revitalization strategy is an important measure to fundamentally solve the rural development problems in the new era. 展开更多
关键词 the No.1 CENTRAL Document text ANALYSIS rural development evolution PROSPECT
下载PDF
Evolution of art form of video animation design under the background of computer graphics system development
11
作者 Jiang Tan 《International Journal of Technology Management》 2017年第6期1-3,共3页
According to the development of discipline and teaching situation of computer graphics, computer graphics analysis in thecurriculum system, the reform of teaching contents and teaching methods, improve students' comp... According to the development of discipline and teaching situation of computer graphics, computer graphics analysis in thecurriculum system, the reform of teaching contents and teaching methods, improve students' computer graphics theory teaching and practiceteaching effects by using limited time, adapt to the social demand for graphics software R & D personnel. Motion design and production are ofgreat importance to film and television animation. This article mainly elaborates the present situation, the characteristic and the master method ofthe movie animation movement design and manufacture. Including the animation, motion animation design and production of organized, plannedproduction features that emphasize the characteristics of movement, exaggeration, force and rhythm, this paper presents the common problemsand solutions in the animation language, and the main differences between the animation design and performance in different forms of animation.Through the animation design and expression of the past and present situation analysis, looking forward to the future animation art movementdesign development. Aesthetic lens performance is the artistic pursuit of many film and television creators. Animation, as a highly hypotheticalart form, which is one of the distinctive artistic features of film and television animation, which is based on the limitation of the camera and is fullof expressive lenses. 展开更多
关键词 Computer graphics system development background film and TELEVISION ANIMATION design art form evolution
下载PDF
The Research on Historical Evolution and Inheritance Development of Ansai waist drum in China
12
作者 Feng YANG 《International English Education Research》 2015年第1期1-3,共3页
This article from the perspective of sports science and sociology to explain the origin and development ofansai waist drum, analyzes the historical evolution of ansai waist drum, analysis of ansai waist drum in proble... This article from the perspective of sports science and sociology to explain the origin and development ofansai waist drum, analyzes the historical evolution of ansai waist drum, analysis of ansai waist drum in problems existing in the process of development, and according to the analysis and the reality put forward the countermeasures of development of ansai waist drum inheritance: transmission of ansai waist drum based on school, and innovation of art form, "waist drum troupe" building, the establishment of various rules and regulations and the drummer cultivation mechanism and strengthening network, books, magazines and other publicity and performances. 展开更多
关键词 Ansai waist drum Historical evolution Inheritance development
下载PDF
On the Relationship between the Evolution of Technological Firms and Their Knowledge Development Regimes
13
作者 BRINK Johan MCKELVEY Maureen 《Journal of Electronic Science and Technology of China》 2006年第4期289-298,共10页
Differences in knowledge regimes and growth dynamics amongst four ideal types of knowledge based firms are analyzed. Two aspects of technological knowledge, technological opportunity and appropriability are traditiona... Differences in knowledge regimes and growth dynamics amongst four ideal types of knowledge based firms are analyzed. Two aspects of technological knowledge, technological opportunity and appropriability are traditionally seen as vital to understand the incentives for research and development activities in firms. However, they do not fully define the technology regimes, when one asks how the knowledge based firm competes. Therefore, the dynamic nature of firm capabilities and knowledge development in terms of expansion and in terms of deepening are also discussed. These two additional aspects of knowledge implies that even if all firms in an industry can be considered to be knowledge intensive these firms do also differ. Using cases of entrepreneurial start-up firms in Sweden, we illustrate whether our conceptual ideas of knowledge development help us understand the diversity and contradictions of firm evolution. Our finding is that firm evolution and capability development is dependent upon both the potential for expanding knowledge, such as by innovations, and by deepening the understanding within established knowledge, such as by learning. This implies that the shaping of a science based industry must be seen in relation both to the value of current knowledge and capabilities together with the sometimes only limited and temporarily advantages of radical innovations. 展开更多
关键词 knowledge regimes firm evolution BIOSCIENCE technology development
下载PDF
Theories and Practical Ideas on Vocabulary Development
14
作者 Ding Liming Sanming Teachers College 《三明学院学报》 1998年第1期45-48,共4页
The reasons for choosing this topic are two: 1) Vocabulary development is the primeconcern for both learners and teachers of a foreign language; 2) Personal teaching experiencehas often challenged me with the question... The reasons for choosing this topic are two: 1) Vocabulary development is the primeconcern for both learners and teachers of a foreign language; 2) Personal teaching experiencehas often challenged me with the question how to develop vocabualry more effectively. Thegeneral objective of this writing is to generalize some enlightening information on the specificarea of vocabulary learning and instruction and to bring forward some ideas practical to ourteaching situation. 展开更多
关键词 theories and Practical ideas on Vocabulary development THAN MORE
下载PDF
A Review on the Evolution and Development of Searle' s Philosophy of Mind
15
作者 Zhao Yingji 《学术界》 CSSCI 北大核心 2013年第12期291-299,共9页
The evolution and development of Searle’s philosophy of mind can be divided into two important stages,i.e.the origin and beginning stage between 1960sand 1970s,the formation and development stage since 1980s.Searle’... The evolution and development of Searle’s philosophy of mind can be divided into two important stages,i.e.the origin and beginning stage between 1960sand 1970s,the formation and development stage since 1980s.Searle’s Speech Act Theory started the research on philosophy of mind,which is considered as the origin of his philosophy of mind.The Theories of Intentionality and Chinese Room Argument are the most important and most influential academic findings in his research in the field of philosophy of mind,which lay a solid theoretical foundation for the formation and development of his theories of philosophy of mind.Searle’s philosophy of mind finds wide prospect in the research field,which provides a new direction to understand the world and probe into mind,proposes a new perspective and methodology for the study of language,and promotes the new development of the study of language. 展开更多
关键词 心灵哲学 塞尔 述评 演进 心境 言语行为理论 学术成果 意向性
下载PDF
The Right to Development of Chinese Ethnic Minorities Promoted in Accordance with the Idea of Putting People First
16
作者 SHERAB NYIMA 《The Journal of Human Rights》 2010年第6期23-28,共6页
I. The Idea of Putting People First and the Right to Development from the Contemporary Perspective of Human Rights
关键词 the Right to development of Chinese Ethnic Minorities Promoted in Accordance with the idea of Putting People First CPC
下载PDF
Eco-environment Evolution and Its Sustainable Development Strategies in Western China 被引量:7
17
作者 张巧显 柯兵 +2 位作者 刘昕 刘国华 吴钢 《Agricultural Science & Technology》 CAS 2010年第1期176-181,共6页
Natural condition in Western China is relatively poor and regional economy level is low. The ecological environment has been seriously damaged by population growth and over-exploitation of natural resources. It is ver... Natural condition in Western China is relatively poor and regional economy level is low. The ecological environment has been seriously damaged by population growth and over-exploitation of natural resources. It is very important for coordinating the regional development and safeguarding ecological security to discuss the eco-environment evolution trend and its sustainable development strategies in Western China. Based on analyzing documents and relative research,the changes of main ecological and environmental problems in the western region,such as degradation of forest and grassland ecosystems,shrinkage of wetland,desertification,water and soil erosion,etc. were synthetically discussed. Then,according to the development trend,some countermeasures for eco-environment protection and rehabilitation and sustainable development were proposed. 展开更多
关键词 Eco-environment evolution Ecological degradation Sustainable development Western China
下载PDF
Measurement and Evolution of High-quality Development Level of Marine Fishery in China 被引量:5
18
作者 LI Bo LIU Zun 《Chinese Geographical Science》 SCIE CSCD 2022年第2期251-267,共17页
High-quality development of marine fisheries provides an important advantage for China to build itself into a maritime power and implement the Blue Granary Plan effectively.Based on the concepts of‘new development’,... High-quality development of marine fisheries provides an important advantage for China to build itself into a maritime power and implement the Blue Granary Plan effectively.Based on the concepts of‘new development’,‘food security’,and the six dimensions of‘openness,innovation,coordination,green,sharing,and security’,in this study,we established an evaluation index system for the high-quality development of China’s marine fishery sector.We applied the entropy method to evaluate the high-quality development level of China’s marine fishery sector from 2000 to 2016 and explored its spatial and temporal evolution rules.Our results indicated that:1)from 2000 to 2016,China’s marine fishery sector was in the primary stage of high-quality development;2)spatially,the highquality development of marine fisheries showed an upward trend in all provinces,autonomous regions,and municipalities in the country(not including Hong Kong,Macao and Taiwan of China),and with time,the distribution pattern changed from single to multi-polarization;3)temporally,the development level of high-quality marine fisheries fluctuated during the study period.From 2000 to 2010,the growth rate in openness was relatively slow,but after 2010,it increased rapidly.Notably,innovation is the driving force for high-quality development.The green and security factors provide a solid guarantee for high-quality development.In the high-quality development of a region,economic development is better coordinated,and the distribution of benefits is more inclusive.This study provides a theoretical basis to formulate effective marine fishery policies for the high-quality development of the marine fishery sector in China.Exploring the high-quality development and evolution process of marine fishery is conducive to promoting the sustainable development of marine fishery industry,ensuring marine fishery food security,and alleviating global food crisis. 展开更多
关键词 marine fisheries high-quality development new development concept food security spatiotemporal evolution comprehensive measurement
下载PDF
Formation and evolution of gas flow channels in the abutment pressure area 被引量:2
19
作者 Zhang Yong Zhang Xibin +2 位作者 Xu Lifeng Zhang Jiangli Zhou Genli 《International Journal of Mining Science and Technology》 SCIE EI 2012年第6期801-807,共7页
The permeability of coal ahead of the working face obviously changes dues to changes in abutment pressure.The formation and evolution of gas flow channels within the abutment pressure area was studied by analyzing the... The permeability of coal ahead of the working face obviously changes dues to changes in abutment pressure.The formation and evolution of gas flow channels within the abutment pressure area was studied by analyzing the fracture extension mechanism and fracture development in different zones of the abutment pressure area.Fracture and damage mechanics theory is used to understand the observations.The following two techniques were used to understand the evolution of gas flow channels:field observation of the characteristic fractures at different positions relative to the working face and fluorescence micrographs of prepared coal samples.Bending tensile fractures develop along an approximately vertical direction that forms a microscopic network of channels in areas of stress concentration.The abutment pressure affects the local stress and,hence,the local gas conduction.The fractures induced by large deformation and plastic flow form macroscopically networked channels in the reduced stress area.Closer to the working face the gas flow channels evolve from microscopic to macroscopic and from isolated to network.Gas permeability continuously increases during this time.This is corroborated by field observations of the displacement of top coal and the gas flow from gas extraction drillings. 展开更多
关键词 ABUTMENT pressure Gas flow CHANNELS FRACTURE EXTENSION mechanism FRACTURE development characteristics evolution process
下载PDF
EVOLUTION AND DEVELOPMENT OF GUANGZHOU-HONG KONG CORRIDOR 被引量:3
20
作者 LI Ping CAO Xiao-shu 《Chinese Geographical Science》 SCIE CSCD 2005年第3期206-211,共6页
With its rapid development in the past two decades, the Pearl River Delta has become one of the most developed regions in China. During this period, an important corridor between Hong Kong and Guangzhou has emerged an... With its rapid development in the past two decades, the Pearl River Delta has become one of the most developed regions in China. During this period, an important corridor between Hong Kong and Guangzhou has emerged and shaped the spatial structure of the region. The growth of this region has been greatly marched with the twin poles of Guangzhou and Hong Kong, and the economic and social development has taken place in a corridor between these two metropolises. This paper provides an analysis of the significance of this corridor in terms of its infrastructure, population, land use, and economic development. Massive infrastructure construction in the corridor has played an important role in its development. The corridor has high-frequent transport, and each transport mode has contributed in a different way to the process of development of the corridor. With high land use intensity and high population density, it is developing the characteristics of a megalopolis. As a pathway of connection between Guangzhou and Hong Kong, the corridor includes not only physical infrastructure, such as roads, railways and airports, but also logistics operations, human resources, information and capital, which plays important roles in accelerating business development. It demonstrates how this Main Street has become one of the most important factors in regional development. 展开更多
关键词 CORRIDOR regional development evolution
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部