1.Introduction The ocean,a vital realm for human existence,encompasses distinct spatial zones,such as the free surface,airspace above the sea,and seabed.It also holds an immense wealth of resources,including oil and g...1.Introduction The ocean,a vital realm for human existence,encompasses distinct spatial zones,such as the free surface,airspace above the sea,and seabed.It also holds an immense wealth of resources,including oil and gas,renewable energy,minerals,and marine biodiversity,forming a crucial component of global life-support systems and representing a valuable asset for human survival and development[1].Moreover,as shown in Fig.1[2],the ocean sectors offer a critical avenue for contributing to many of the 17 United Nations Sustainable Development Goals for global development[3].展开更多
Today,the world is undergoing extremely rapid and profound changes.The Two Sessions held each March in Beijing provide an excellent opportunity to review the changes taking place in the world,reflect on the path China...Today,the world is undergoing extremely rapid and profound changes.The Two Sessions held each March in Beijing provide an excellent opportunity to review the changes taking place in the world,reflect on the path China has taken,its achievements and challenges,and evaluate future steps.展开更多
Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of na...Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of national and provincial economic and technological development zones and high-tech industrial zones in China were collected and arranged.Kernel density analysis and other GIS spatial analysis techniques were used to analyze the evolution laws of spatial patterns of economic and technological development zones and high-tech industrial zones in cities from 2006 to 2018.First,the agglomeration intensity was compared by measuring the degree of regional agglomeration and dispersion on the two time nodes.Next,kernel density method was used to explore the evolution of the two in the spatial layout and location,and analyze development commonness and difference of economic and technological development zones and high-tech industrial zones.Finally,the trend and reason of spatial evolution of development zones with different leading industries were explored.Research results show that:①the agglomeration degree of layout of high-tech industrial zones is stronger than that of economic and technological development zones,and there are similarities and differences in distribution trend of spatial patterns of the two types of development zones;②the distribution of labor-intensive,capital-intensive and technology-intensive development zones is concentrated at smaller scales and dispersed at larger ones;③although there are differences between the economic and technological development zones and the high-tech industrial zones in the goal,support,structure and function,management system and so on,their spatial development presents a trend of convergence.In the future,when enhancing urban-rural planning and public administration,governments should combine the trend of industrial transformation and upgrading,and optimize spatial layout of development zones by adjusting industrial structure,layout,transportation and land use.展开更多
In recent years,with high-speed development of economy and society,and fast propulsion of industrialization and urbanization process in the development zone,average annual land demand in the development zone also quic...In recent years,with high-speed development of economy and society,and fast propulsion of industrialization and urbanization process in the development zone,average annual land demand in the development zone also quickly enlarges,and the contradiction between high-speed growth of economy and shortage of land resources is apparent increasingly. Meanwhile,to guarantee crop safety and stick to 0. 12 billion hm2of farmland red line as a rigid constraint which could not be exceeded,the supply-demand contradiction of industrial land is more and more prominent. With industrial land scale continues to enlarge,land resources become more and more scarce,but there exists the phenomenon of low-efficiency land use and even idle. For land use characteristics of the development zone,taking Hefei City Economic and Technological Development Zone as an example,the countermeasures of perfecting industrial land transfer mechanism in the development zone are proposed.展开更多
Recent reports about economic and technological developmentdistrict brought me an idea to visit Wang Deye of director of Ad-ministration Commission of Guangzhou Economic and Technol-ogy District (GETDD).The reports ga...Recent reports about economic and technological developmentdistrict brought me an idea to visit Wang Deye of director of Ad-ministration Commission of Guangzhou Economic and Technol-ogy District (GETDD).The reports gave me a definite informa-tion:There is a new shock wave of pioneering cause in GETDD.The development trend can not be held back and the zone willmarch ahead of all economic and technological development zonesin China again.Facing the new shock wave,how will people of GETDD reactand to add their achievements for a better future?After the removing of the "favorable policy" granted by Cen-tral government,how will they open a new sea route of "systemdrive" in the second poneering phase?Facing the new chance of Pearl River Delta Economic Area,how will they set up its forerunner image and utmost importance?展开更多
The Shanghai Hongqiao Economic and Technological Development District is an entrance to Shanghai because it is connected to the Hongqiao Airport. The district occupies an area of 65.2 hectares. It is the only way from
There is an intrinsic traction force in the technological development which has various manifestations. It is from nonlinear interaction that occurs among the essential elements of technology and among the relevant te...There is an intrinsic traction force in the technological development which has various manifestations. It is from nonlinear interaction that occurs among the essential elements of technology and among the relevant technology. It is not the only decisive factor but to interweave with other tensions in the development of technology.展开更多
The Fuyang Economic and TechnologicalDevelopment area(FETDA) is aprovincial development area approvedby the Anhui provincial government.Situatedin the south of the city,the area is close to theold town in the north an...The Fuyang Economic and TechnologicalDevelopment area(FETDA) is aprovincial development area approvedby the Anhui provincial government.Situatedin the south of the city,the area is close to theold town in the north and bordering to thesouth the outer ring road,and the Beijing-Kowloon railway in the east.To the southeastis the large freight terminal of the railway.And the Xiqinghe River runs along its westernborder.It is four km away from Fuyangairport and national highway 105 and theFuyang-Yingzhou highway run through thearea,which covers a total area of eight sqkm. With all kinds of public facilities,thearea will be operated in line with展开更多
The 23rd meeting of the Central Committee for Comprehensively Deepening Reform, presided over by General Secretary Xi Jinping, adopted the Guiding Opinions on Strengthening the Governance of Science and Technology Eth...The 23rd meeting of the Central Committee for Comprehensively Deepening Reform, presided over by General Secretary Xi Jinping, adopted the Guiding Opinions on Strengthening the Governance of Science and Technology Ethics on 17 December 2021. On 20March 2022, the General Office of the CPC Central Committee and the General Office of the State Council issued the Opinions on Strengthening the Governance of Science and Technology Ethics.展开更多
The announcer on the giant screen greeted visitors to the Wuzhen International lnternet Exhibition Center with a cheery voice. ＂Good morning everyone! I will be your news anchor for today,＂ said the male voice. But ...The announcer on the giant screen greeted visitors to the Wuzhen International lnternet Exhibition Center with a cheery voice. ＂Good morning everyone! I will be your news anchor for today,＂ said the male voice. But this was no ordinary announcer： his voice and appearance have been entirely generated by artificial intelligence technology.展开更多
Recvcling the Rare Earth Metals of E-Waste Recycling the valuable rare earth metals found in advanced electronics from smartphones to plasma screen TVs has been a challenge for both manufacturers and environmental gro...Recvcling the Rare Earth Metals of E-Waste Recycling the valuable rare earth metals found in advanced electronics from smartphones to plasma screen TVs has been a challenge for both manufacturers and environmental groups.Yale researchers,though,have developed a technology that could recover these materials for reuse.Desiree Plata,the John J.Lee Assistant Professor of Chemical and Environmental Engineering,and展开更多
This article analyses different characteristics of scale,site selection and function of the current economic andtehnological development zones in our country.It further proposes that it is inappropriate for the econom...This article analyses different characteristics of scale,site selection and function of the current economic andtehnological development zones in our country.It further proposes that it is inappropriate for the economic andtechnological development zones to follow the“pattern of the special zones”,but a new pattern of“small scale,unitaryfunction and closeness to old city”should be adopted to fit in with the practical conditions in our country.The scale,landuse structure and the relations between the development zone and the old city are the basic issues in planning forthe development zones.These three essential elements constitute the pattern of planning which determines to a certainextent the success or failure of the development zones.展开更多
Based on the technological demands for significantly enhancing oil recovery and long-term CO_(2)sequestration in the lacustrine oil reservoirs of China,this study systematically reviews the progress and practices of C...Based on the technological demands for significantly enhancing oil recovery and long-term CO_(2)sequestration in the lacustrine oil reservoirs of China,this study systematically reviews the progress and practices of CO_(2)flooding and storage technologies in recent years.It addresses the key technological needs and challenges faced in scaling up the application of CO_(2)flooding and storage to mature,developed oil fields,and analyzes future development directions.During the pilot test phase(2006-2019),continuous development and application practices led to the establishment of the first-generation CO_(2)flooding and storage technology system for lacustrine reservoirs.In the industrialization phase(since 2020),significant advances and insights have been achieved in terms of confined phase behavior,storage mechanisms,reservoir engineering,sweep control,engineering process and storage monitoring,enabling the maturation of the second-generation CO_(2)flooding and storage theories and technologies to effectively support the demonstration projects of Carbon Capture,Utilization and Storage(CCUS).To overcome key technical issues such as low miscibility,difficulty in gas channeling control,high process requirements,limited application scenarios,and coordination challenges in CO_(2)flooding and storage,and to support the large-scale application of CCUS,it is necessary to strengthen research on key technologies for establishing the third-generation CO_(2)flooding and storage technological system incorporating miscibility enhancement and transformation,comprehensive regulation for sweep enhancement,whole-process engineering techniques and equipment,long-term storage monitoring safety,and synergistic optimization of flooding and storage.展开更多
When the human society steps into a new epoch, we, in cooperation with the World Intellectual Property Organization (WIPO), hold the Sino-African Intellectual Property Forum, on which we may exchange experiences in de...When the human society steps into a new epoch, we, in cooperation with the World Intellectual Property Organization (WIPO), hold the Sino-African Intellectual Property Forum, on which we may exchange experiences in developing intellectual property systems and discuss issues of common concern. The themes listed in the agenda not only mirror the emerging issues of the development of the international intellectual property system, but also carry significant weight to展开更多
Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehens...Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehensive review of commonly employed coalbed methane extraction technologies.It then delves into several critical issues in the current stage of CBM exploration and development in China,including the compatibility of existing technologies with CBM reservoirs,the characteristics and occurrence states of CBM reservoirs,critical desorption pressure,and gas generation mechanisms.Our research indicates that current CBM exploration and development technologies in China have reached an internationally advanced level,yet the industry is facing unprecedented challenges.Despite progress in low-permeability,high-value coal seams,significant breakthroughs have not been achieved in exploring other types of coal seams.For different coal reservoirs,integrated extraction technologies have been developed,such as surface pre-depressurisation and segmented hydraulic fracturing of coal seam roof strata.Additionally,techniques like large-scale volume fracturing in horizontal wells have been established,significantly enhancing reservoir stimulation effects and coalbed methane recovery rates.However,all of these technologies are fundamentally based on permeation.These technologies lack direct methods aimed at enhancing the diffusion rate of CBM,thereby failing to fully reflect the unique characteristics of CBM.Current CBM exploration and development theories and technologies are not universally applicable to all coal seams.They do not adequately account for the predominantly adsorbed state of CBM,and the complex and variable gas generation mechanisms further constrain CBM development in China.Finally,continuous exploration of new deep CBM exploration technologies is necessary.Integrating more effective reservoir stimulation technologies is essential to enhance technical adaptability concerning CBM reservoir characteristics,gas occurrence states,and gas generation mechanisms,ultimately achieving efficient CBM development.We conclude that while China possesses a substantial foundation of deep fractured CBM resources,industry development is constrained and requires continuous exploration of new CBM exploration and development technologies to utilize these resources effectively.展开更多
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
Migration and innovation is the driving force of scientific and technological development.By analyzing the coupling relationship between the two,this paper finds out the common elements shared by the two factors,and c...Migration and innovation is the driving force of scientific and technological development.By analyzing the coupling relationship between the two,this paper finds out the common elements shared by the two factors,and constructs the coupling guarantee mechanism between them,so as to provide suggestions for the coordination,win-win and synchronous benign development of the spirit of makers and the development of scientific and technological innovation,and promote the sustainable development of the national innovation system.展开更多
Economic and technological development zones (ETDZs) constitute special designated areas emerging in a period of economic transition characterized by the adoption of special policies and the creation of favorable envi...Economic and technological development zones (ETDZs) constitute special designated areas emerging in a period of economic transition characterized by the adoption of special policies and the creation of favorable environment conducive to the attraction of foreign capital and technology and to the development of an outward-oriented economy. At present, there are 41 State-level ETDZs, which together展开更多
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
This paper presents an overview of the recent developments in hybrid wind-wave energy.With the focus on floating concepts,the possible configurations introduced in the literature are categorized and depicted,and the m...This paper presents an overview of the recent developments in hybrid wind-wave energy.With the focus on floating concepts,the possible configurations introduced in the literature are categorized and depicted,and the main conclusions obtained from the references are summarized.Moreover,offshore wind and wave resources are discussed in terms of complementarity and supplementarity,offering a new perspective to developing hybrid wind-wave energy systems that look for synergies not limited to maximizing power output.Then,the feasibility of the concepts under development is discussed in detail,with focus on technical feasibility,dynamic feasibility and limitations of the methods employed.The hybrid configurations that surpassed the experimental validation phase are highlighted,and the experimental results are summarized.By compiling more than 40 floating wind turbine concepts,new relations are drawn between power,wind turbine dimensions,platforms’draft and displacement,which are further related to the payload allowance of the units to accommodate wave devices and onboard power take-off systems.Bearing in mind that it is a challenge to model the exact dynamics of hybrid floating wind-wave platforms,this paper elucidates the current research gaps,limitations and future trends in the field.Lastly,based on the overview and topics discussed,several major conclusions are drawn concerning hybrid synergies,dynamics and hydrodynamics of hybrid platforms,feasibility of concepts,among other regards.展开更多
基金supported by the National Natural Science Foun-dation of China(52088102)the KeyR&DProgram of Shandong Province,China(2021ZLGX04).
文摘1.Introduction The ocean,a vital realm for human existence,encompasses distinct spatial zones,such as the free surface,airspace above the sea,and seabed.It also holds an immense wealth of resources,including oil and gas,renewable energy,minerals,and marine biodiversity,forming a crucial component of global life-support systems and representing a valuable asset for human survival and development[1].Moreover,as shown in Fig.1[2],the ocean sectors offer a critical avenue for contributing to many of the 17 United Nations Sustainable Development Goals for global development[3].
文摘Today,the world is undergoing extremely rapid and profound changes.The Two Sessions held each March in Beijing provide an excellent opportunity to review the changes taking place in the world,reflect on the path China has taken,its achievements and challenges,and evaluate future steps.
基金Sponsored by Peking University (Shenzhen) Future City Lab Tiehan Research Fund。
文摘Economic and technological development zone and high-tech industrial zone are important types of development zone in China,and there are differences in their connotation and goal setting.In this paper,basic data of national and provincial economic and technological development zones and high-tech industrial zones in China were collected and arranged.Kernel density analysis and other GIS spatial analysis techniques were used to analyze the evolution laws of spatial patterns of economic and technological development zones and high-tech industrial zones in cities from 2006 to 2018.First,the agglomeration intensity was compared by measuring the degree of regional agglomeration and dispersion on the two time nodes.Next,kernel density method was used to explore the evolution of the two in the spatial layout and location,and analyze development commonness and difference of economic and technological development zones and high-tech industrial zones.Finally,the trend and reason of spatial evolution of development zones with different leading industries were explored.Research results show that:①the agglomeration degree of layout of high-tech industrial zones is stronger than that of economic and technological development zones,and there are similarities and differences in distribution trend of spatial patterns of the two types of development zones;②the distribution of labor-intensive,capital-intensive and technology-intensive development zones is concentrated at smaller scales and dispersed at larger ones;③although there are differences between the economic and technological development zones and the high-tech industrial zones in the goal,support,structure and function,management system and so on,their spatial development presents a trend of convergence.In the future,when enhancing urban-rural planning and public administration,governments should combine the trend of industrial transformation and upgrading,and optimize spatial layout of development zones by adjusting industrial structure,layout,transportation and land use.
文摘In recent years,with high-speed development of economy and society,and fast propulsion of industrialization and urbanization process in the development zone,average annual land demand in the development zone also quickly enlarges,and the contradiction between high-speed growth of economy and shortage of land resources is apparent increasingly. Meanwhile,to guarantee crop safety and stick to 0. 12 billion hm2of farmland red line as a rigid constraint which could not be exceeded,the supply-demand contradiction of industrial land is more and more prominent. With industrial land scale continues to enlarge,land resources become more and more scarce,but there exists the phenomenon of low-efficiency land use and even idle. For land use characteristics of the development zone,taking Hefei City Economic and Technological Development Zone as an example,the countermeasures of perfecting industrial land transfer mechanism in the development zone are proposed.
文摘Recent reports about economic and technological developmentdistrict brought me an idea to visit Wang Deye of director of Ad-ministration Commission of Guangzhou Economic and Technol-ogy District (GETDD).The reports gave me a definite informa-tion:There is a new shock wave of pioneering cause in GETDD.The development trend can not be held back and the zone willmarch ahead of all economic and technological development zonesin China again.Facing the new shock wave,how will people of GETDD reactand to add their achievements for a better future?After the removing of the "favorable policy" granted by Cen-tral government,how will they open a new sea route of "systemdrive" in the second poneering phase?Facing the new chance of Pearl River Delta Economic Area,how will they set up its forerunner image and utmost importance?
文摘The Shanghai Hongqiao Economic and Technological Development District is an entrance to Shanghai because it is connected to the Hongqiao Airport. The district occupies an area of 65.2 hectares. It is the only way from
文摘There is an intrinsic traction force in the technological development which has various manifestations. It is from nonlinear interaction that occurs among the essential elements of technology and among the relevant technology. It is not the only decisive factor but to interweave with other tensions in the development of technology.
文摘The Fuyang Economic and TechnologicalDevelopment area(FETDA) is aprovincial development area approvedby the Anhui provincial government.Situatedin the south of the city,the area is close to theold town in the north and bordering to thesouth the outer ring road,and the Beijing-Kowloon railway in the east.To the southeastis the large freight terminal of the railway.And the Xiqinghe River runs along its westernborder.It is four km away from Fuyangairport and national highway 105 and theFuyang-Yingzhou highway run through thearea,which covers a total area of eight sqkm. With all kinds of public facilities,thearea will be operated in line with
文摘The 23rd meeting of the Central Committee for Comprehensively Deepening Reform, presided over by General Secretary Xi Jinping, adopted the Guiding Opinions on Strengthening the Governance of Science and Technology Ethics on 17 December 2021. On 20March 2022, the General Office of the CPC Central Committee and the General Office of the State Council issued the Opinions on Strengthening the Governance of Science and Technology Ethics.
文摘The announcer on the giant screen greeted visitors to the Wuzhen International lnternet Exhibition Center with a cheery voice. ＂Good morning everyone! I will be your news anchor for today,＂ said the male voice. But this was no ordinary announcer： his voice and appearance have been entirely generated by artificial intelligence technology.
文摘Recvcling the Rare Earth Metals of E-Waste Recycling the valuable rare earth metals found in advanced electronics from smartphones to plasma screen TVs has been a challenge for both manufacturers and environmental groups.Yale researchers,though,have developed a technology that could recover these materials for reuse.Desiree Plata,the John J.Lee Assistant Professor of Chemical and Environmental Engineering,and
文摘This article analyses different characteristics of scale,site selection and function of the current economic andtehnological development zones in our country.It further proposes that it is inappropriate for the economic andtechnological development zones to follow the“pattern of the special zones”,but a new pattern of“small scale,unitaryfunction and closeness to old city”should be adopted to fit in with the practical conditions in our country.The scale,landuse structure and the relations between the development zone and the old city are the basic issues in planning forthe development zones.These three essential elements constitute the pattern of planning which determines to a certainextent the success or failure of the development zones.
基金Supported by the China National Key R&D Program(2023YFF0614100)National Science and Technology Major Project of China(2024ZD14066)+1 种基金Major Project of PetroChina Company Limited(2021ZZ01)Key R&D Project of Xinjiang Uygur Autonomous Region of China(2024B03001).
文摘Based on the technological demands for significantly enhancing oil recovery and long-term CO_(2)sequestration in the lacustrine oil reservoirs of China,this study systematically reviews the progress and practices of CO_(2)flooding and storage technologies in recent years.It addresses the key technological needs and challenges faced in scaling up the application of CO_(2)flooding and storage to mature,developed oil fields,and analyzes future development directions.During the pilot test phase(2006-2019),continuous development and application practices led to the establishment of the first-generation CO_(2)flooding and storage technology system for lacustrine reservoirs.In the industrialization phase(since 2020),significant advances and insights have been achieved in terms of confined phase behavior,storage mechanisms,reservoir engineering,sweep control,engineering process and storage monitoring,enabling the maturation of the second-generation CO_(2)flooding and storage theories and technologies to effectively support the demonstration projects of Carbon Capture,Utilization and Storage(CCUS).To overcome key technical issues such as low miscibility,difficulty in gas channeling control,high process requirements,limited application scenarios,and coordination challenges in CO_(2)flooding and storage,and to support the large-scale application of CCUS,it is necessary to strengthen research on key technologies for establishing the third-generation CO_(2)flooding and storage technological system incorporating miscibility enhancement and transformation,comprehensive regulation for sweep enhancement,whole-process engineering techniques and equipment,long-term storage monitoring safety,and synergistic optimization of flooding and storage.
文摘When the human society steps into a new epoch, we, in cooperation with the World Intellectual Property Organization (WIPO), hold the Sino-African Intellectual Property Forum, on which we may exchange experiences in developing intellectual property systems and discuss issues of common concern. The themes listed in the agenda not only mirror the emerging issues of the development of the international intellectual property system, but also carry significant weight to
基金supported by the National Natural Science Foundation of China(52074045,52274074)the Science Fund for Distinguished Young Scholars of Chongqing(CSTB2022NSCQ-JQX0028).
文摘Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehensive review of commonly employed coalbed methane extraction technologies.It then delves into several critical issues in the current stage of CBM exploration and development in China,including the compatibility of existing technologies with CBM reservoirs,the characteristics and occurrence states of CBM reservoirs,critical desorption pressure,and gas generation mechanisms.Our research indicates that current CBM exploration and development technologies in China have reached an internationally advanced level,yet the industry is facing unprecedented challenges.Despite progress in low-permeability,high-value coal seams,significant breakthroughs have not been achieved in exploring other types of coal seams.For different coal reservoirs,integrated extraction technologies have been developed,such as surface pre-depressurisation and segmented hydraulic fracturing of coal seam roof strata.Additionally,techniques like large-scale volume fracturing in horizontal wells have been established,significantly enhancing reservoir stimulation effects and coalbed methane recovery rates.However,all of these technologies are fundamentally based on permeation.These technologies lack direct methods aimed at enhancing the diffusion rate of CBM,thereby failing to fully reflect the unique characteristics of CBM.Current CBM exploration and development theories and technologies are not universally applicable to all coal seams.They do not adequately account for the predominantly adsorbed state of CBM,and the complex and variable gas generation mechanisms further constrain CBM development in China.Finally,continuous exploration of new deep CBM exploration technologies is necessary.Integrating more effective reservoir stimulation technologies is essential to enhance technical adaptability concerning CBM reservoir characteristics,gas occurrence states,and gas generation mechanisms,ultimately achieving efficient CBM development.We conclude that while China possesses a substantial foundation of deep fractured CBM resources,industry development is constrained and requires continuous exploration of new CBM exploration and development technologies to utilize these resources effectively.
文摘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.
基金This paper is one of the achievements of the general projects of the National Social Science Foundation project in 2017,the project name is"Study on the Cooperative Development Mechanism Between Librarians and Creators in the Library Maker Space Service System"(item number:17BTQ033)。
文摘Migration and innovation is the driving force of scientific and technological development.By analyzing the coupling relationship between the two,this paper finds out the common elements shared by the two factors,and constructs the coupling guarantee mechanism between them,so as to provide suggestions for the coordination,win-win and synchronous benign development of the spirit of makers and the development of scientific and technological innovation,and promote the sustainable development of the national innovation system.
基金This article is financially supported by National Natural Science Foundation of China.
文摘Economic and technological development zones (ETDZs) constitute special designated areas emerging in a period of economic transition characterized by the adoption of special policies and the creation of favorable environment conducive to the attraction of foreign capital and technology and to the development of an outward-oriented economy. At present, there are 41 State-level ETDZs, which together
基金Special Fund for Basic Scientific Research Business Expenses of Central Public Welfare Scientific Research Institutions(S201947)。
文摘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.
基金supported by the Portuguese Foundation for Science and Technology(Fundação para a Ciência e Tecnologia-FCT)it contributes to the Strategic Research Plan of the Centre for Marine Technology and Ocean Engineering(Grant No.UIDB/UIDP/00134/2020)funded the first author for his PhD Scholarship(Grant No.SFRH/BD/145602/2019).
文摘This paper presents an overview of the recent developments in hybrid wind-wave energy.With the focus on floating concepts,the possible configurations introduced in the literature are categorized and depicted,and the main conclusions obtained from the references are summarized.Moreover,offshore wind and wave resources are discussed in terms of complementarity and supplementarity,offering a new perspective to developing hybrid wind-wave energy systems that look for synergies not limited to maximizing power output.Then,the feasibility of the concepts under development is discussed in detail,with focus on technical feasibility,dynamic feasibility and limitations of the methods employed.The hybrid configurations that surpassed the experimental validation phase are highlighted,and the experimental results are summarized.By compiling more than 40 floating wind turbine concepts,new relations are drawn between power,wind turbine dimensions,platforms’draft and displacement,which are further related to the payload allowance of the units to accommodate wave devices and onboard power take-off systems.Bearing in mind that it is a challenge to model the exact dynamics of hybrid floating wind-wave platforms,this paper elucidates the current research gaps,limitations and future trends in the field.Lastly,based on the overview and topics discussed,several major conclusions are drawn concerning hybrid synergies,dynamics and hydrodynamics of hybrid platforms,feasibility of concepts,among other regards.
