Sustainable development of mountain areas and resource cities has been a significant issue worldwide. Transformation of mountain resource cities is facing tremendous difficulties. In the context of National Major Func...Sustainable development of mountain areas and resource cities has been a significant issue worldwide. Transformation of mountain resource cities is facing tremendous difficulties. In the context of National Major Function-oriented Zone Planning raised to a national strategic level in China, it is important to effectively implement the planning by studying geographical space development zone classification of prefecture- and county-level cities based on their major function orientation. This research is even more critical for the transformation of mountain resource cities. In this study, we evaluated geographical space development suitability, and classified geographical space development zones for Dongchuan Distric in Kunming City of Yunan Province, China, a typical mountain resource city. A quantitative grid-based evaluation was conducted using key-factor identification and restrictive-supportive comprehensive index determinati based on a geographic information system framework with different source data. The results included a classification of geographical space of Dongchuan into five types: the prohibited development zone, the inappropriate development zone, the controlled development zone, the moderate development zone and the preferential development zone. The distribution characteristics of geographical space development zones showed that the proportion of the prohibited development zone is the highest, while that of the other four development zones is comparatively lower and significantly fragmented. The geographical space development suitability is greatly controlled by the geomorphic pattern. Although Dongchuan is extremely restrained in terms of suitable geographical space for industrialization and urbanization, it still has the certain preferential and moderate development zones with an area of 207.81 km2 with large parts being concentrated and contiguous, which makes these areas the most favorable for development. Only by adapting to this reality and implementing centralized development strategy in the regions with higher suitability may Dongchuan achieve smooth transformation from expansion mode to compact mode and its sustainable development capacity may be improved. Suggestions with an angle of industrial and spatial development pattern were put forward for the transformation of the city in future.展开更多
In the third decade of the 21st century,the aerospace field is evolving at an unprecedented pace towards intelligence and autonomy.As competition for space resource development intensifies,breakthroughs in near-space ...In the third decade of the 21st century,the aerospace field is evolving at an unprecedented pace towards intelligence and autonomy.As competition for space resource development intensifies,breakthroughs in near-space vehicle technology emerge,and the concept of drone swarm warfare matures,traditional rule-based and experience-driven battlefield situation awareness models are struggling to meet the demands of complex adversarial environments.This special issue brings together the latest research findings from fields such as computer science and technology,electronic engineering,and cognitive science,systematically exploring the cognitive revolution driven by the deep integration of next-generation artificial intelligence and aerospace engineering,all centered around the core theme of"Intelligent Situation Awareness"(ISA).展开更多
Earth was broken for the ZTE R&D Building at theheadquarters on October 28, 2003. Hou Weigui,President of ZTE, delivered a speech on the cere-mony. He said:“As part of the development strate-gy of ZTE, the new bu...Earth was broken for the ZTE R&D Building at theheadquarters on October 28, 2003. Hou Weigui,President of ZTE, delivered a speech on the cere-mony. He said:“As part of the development strate-gy of ZTE, the new building will play an importantrole in improving the overall R&D arrangement andthe environment of production and R&D, reducingthe operating cost and enhancing the image of thewhole company.”The R&D building will be the Shenzhen R&D展开更多
Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage mechanisms.In this s...Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage mechanisms.In this study,the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage experiments.On the basis of these experiments,a numerical simulation model(based on the special seepage mechanism)and an inverse dynamic reserve algorithm(with different equivalent drainage areas)were developed.The well spacing ranges of Classes I,II,and III wells in the Q gas field are determined to be 802–1,000,600–662,and 285–400 m,respectively,with their average ranges as 901,631,and 342.5 m,respectively.By considering both the pairs of parallel well groups and series well groups as examples,the reliability of the calculation results is verified.It is shown that the combination of the two models can reduce errors and provide accurate results.展开更多
Mr. Chairman, distinguished colleagues and vips, ladies and gentlemen, It is a great pleasure, also a privilege for me to address this august body which is a high-level gathering attended by top experts of the world...Mr. Chairman, distinguished colleagues and vips, ladies and gentlemen, It is a great pleasure, also a privilege for me to address this august body which is a high-level gathering attended by top experts of the world and practitioners with authority in management, operational, business matters in both air and space utilization and their legal aspects. Your presence will undoubtedly increase the brilliance of展开更多
This paper discusses the urgency to further develop China’s space technological industry;analyzes the gaps between China and other advanced countries in space industry,including technological level,development scale,...This paper discusses the urgency to further develop China’s space technological industry;analyzes the gaps between China and other advanced countries in space industry,including technological level,development scale,application scope and investment;describes the current severe situation that the China’s space industry is faced with and proposes the overall objective,guiding principles and major tasks of China’s space technological sector in the Ninth-Five Year Plan and the coming decade.Finally,it proposes some policies and effective measures to speed up the development of China’s space industry to meet the challenge in the 21st century.展开更多
Now the China National Astronau-tics Industry Corporation is devcting more efforts to narrowing the gaps and has also begun research into manned satellites,which it hopes will be real-ized by the end of this century.
China’s space cause is based on the development of missile technology. In the 1950s, new China, which was just founded, decided to keep pace with the jet technology times, to begin developing missile and rocket scien...China’s space cause is based on the development of missile technology. In the 1950s, new China, which was just founded, decided to keep pace with the jet technology times, to begin developing missile and rocket science and technology, and to establish China’s new space scientific and technological industry.展开更多
For China,at the turn of the century,how to keep the position of the space power,how to stimulate the enthusiasm of the space technicians and how to keep pace with the world space technology,all of these questions lie...For China,at the turn of the century,how to keep the position of the space power,how to stimulate the enthusiasm of the space technicians and how to keep pace with the world space technology,all of these questions lie ahead of the Chinese people.So we may say China’s space industry now is in the key stage.If the space industry draws great attention from the central government and the people of the country,it will have a brilliant future in the 21st century.We should put our eyes on the 21st century and prepare to explore space resources.It is difficult for us to keep pace with the times if we do not explore space resources and try to earn "the money in space".展开更多
By reviewing the theories and methods of resource and environmental carrying capacity evaluation and suitability evaluation of land and space development,it provides theoretical and technical support for rational layo...By reviewing the theories and methods of resource and environmental carrying capacity evaluation and suitability evaluation of land and space development,it provides theoretical and technical support for rational layout and optimization of land and space development pattern.From the aspects of resource carrying capacity,environmental carrying capacity,the importance of ecological protection,the suitability of agricultural production,and the suitability of urban construction,we sort out domestic and foreign documents.The evaluation of resource carrying capacity has changed from single-factor evaluation to multi-factor comprehensive evaluation.At present,the optimization of land use pattern based on the“three-generation”space is still under exploration,it is not enough to systematize and summarize the thought of optimizing the spatial pattern of the national territory.The theoretical framework,model,method and index of“dual evaluation”of territorial space need to be improved continuously,it also needs the scientific analysis and cognition from the natural direction to the human location direction and the spatial equilibrium state as the new driving force.展开更多
Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understand...Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understanding the ecological process of restored vegetation is quite important for ecosystem reconstruction. Distinguishing stand development stages and analyzing the dynamic spatial patterns could provide insights into significant community coexistence mechanisms. In the present study, eight permanent study areas were established according to the substituting space for time method in Changbai Mountains of north-eastern China. The optimal division method was used to quantify the successional series into different stand development stages, and the point pattern analysis method(L(r) function) was used to analyse the dynamic changes in spatial patterns and interspecific associations. Our results suggested that:(1) The stand development process was divided into five stages: the first three stages were poplar-birch secondary forests in different stages of recovery, the fourth stage was thespruce-fir mixed forest, and the last stage was the primary broadleaf-Korean pine forest;(2) The spatial pattern showed an aggregated distribution at a small scale and changed to a random distribution as the scale increased in poplar-birch secondary forests, but the spatial pattern appeared to be randomly distributed in spruce-fir mixed forest and broadleafKorean pine forest;(3) The interspecific associations between pioneer species and climax species changed from negative to positive among the different stand stages, and environmental resources were shared among these species. Interspecific differences in shade tolerance among the tree species were key determinants of forest dynamics and structure. Our study is vital to the understanding of the forest development;thus, the spatial change features should receive greater attention when forest management is being planned and restoration strategies are being developed for the Changbai Mountains.展开更多
In 1993, China Aerospace Corporation(CASC) announced that it would give priority to the development of satellites and their applications, automobiles and components, computers and their applications, and regard them a...In 1993, China Aerospace Corporation(CASC) announced that it would give priority to the development of satellites and their applications, automobiles and components, computers and their applications, and regard them as its three-pillar industries, which was "a historic and significant strategic decision" said Mr. Liu Jiyuan, the president of CASC. New and展开更多
1 Introduction The explosive growth of the global commercial space industry has brought low-Earth orbit(LEO)satellite constellation programs,such as Starlink and Qianfan,to a pivotal stage in the evolution of space de...1 Introduction The explosive growth of the global commercial space industry has brought low-Earth orbit(LEO)satellite constellation programs,such as Starlink and Qianfan,to a pivotal stage in the evolution of space development toward commercialization.1 Traditional space missions have stringent requirements for mission risk and payload mass,while commercial satellite design emphasizes economic viability.2 This systemic transformation has not only redefined the operational framework of aerospace engineering but also opened critical pathways for the spatial application of emerging photovoltaic technologies.Perovskite solar cells(PSCs),endowed with high specific power and cost-effectiveness,have demonstrated competitive potential against silicon-based counterparts in terrestrial applications.3 Crucially,their application prospects are particularly promising in the space domain,where device mass,power density,and cost efficiency are critical design constraints.展开更多
This article elaborated the characteristics of settlement shape in detail with examples. Aiming at the negative effects on settlement shape by construction, we put forward some measures, such as respect for ecological...This article elaborated the characteristics of settlement shape in detail with examples. Aiming at the negative effects on settlement shape by construction, we put forward some measures, such as respect for ecological environment, selection mode of space development, protection of historical features, and excavation of culture connotation, so as to realize the protection of settlement shape.展开更多
基金Under the auspices of National Basic Research Program of China(No.2015CB452706)National Natural Science Foundation of China(No.41301193)Knowledge Innovation Program of Chinese Academy of Sciences(No.KZCX2-YW-333)
文摘Sustainable development of mountain areas and resource cities has been a significant issue worldwide. Transformation of mountain resource cities is facing tremendous difficulties. In the context of National Major Function-oriented Zone Planning raised to a national strategic level in China, it is important to effectively implement the planning by studying geographical space development zone classification of prefecture- and county-level cities based on their major function orientation. This research is even more critical for the transformation of mountain resource cities. In this study, we evaluated geographical space development suitability, and classified geographical space development zones for Dongchuan Distric in Kunming City of Yunan Province, China, a typical mountain resource city. A quantitative grid-based evaluation was conducted using key-factor identification and restrictive-supportive comprehensive index determinati based on a geographic information system framework with different source data. The results included a classification of geographical space of Dongchuan into five types: the prohibited development zone, the inappropriate development zone, the controlled development zone, the moderate development zone and the preferential development zone. The distribution characteristics of geographical space development zones showed that the proportion of the prohibited development zone is the highest, while that of the other four development zones is comparatively lower and significantly fragmented. The geographical space development suitability is greatly controlled by the geomorphic pattern. Although Dongchuan is extremely restrained in terms of suitable geographical space for industrialization and urbanization, it still has the certain preferential and moderate development zones with an area of 207.81 km2 with large parts being concentrated and contiguous, which makes these areas the most favorable for development. Only by adapting to this reality and implementing centralized development strategy in the regions with higher suitability may Dongchuan achieve smooth transformation from expansion mode to compact mode and its sustainable development capacity may be improved. Suggestions with an angle of industrial and spatial development pattern were put forward for the transformation of the city in future.
文摘In the third decade of the 21st century,the aerospace field is evolving at an unprecedented pace towards intelligence and autonomy.As competition for space resource development intensifies,breakthroughs in near-space vehicle technology emerge,and the concept of drone swarm warfare matures,traditional rule-based and experience-driven battlefield situation awareness models are struggling to meet the demands of complex adversarial environments.This special issue brings together the latest research findings from fields such as computer science and technology,electronic engineering,and cognitive science,systematically exploring the cognitive revolution driven by the deep integration of next-generation artificial intelligence and aerospace engineering,all centered around the core theme of"Intelligent Situation Awareness"(ISA).
文摘Earth was broken for the ZTE R&D Building at theheadquarters on October 28, 2003. Hou Weigui,President of ZTE, delivered a speech on the cere-mony. He said:“As part of the development strate-gy of ZTE, the new building will play an importantrole in improving the overall R&D arrangement andthe environment of production and R&D, reducingthe operating cost and enhancing the image of thewhole company.”The R&D building will be the Shenzhen R&D
基金the Major Science and Technology Project of Southwest Oil and Gas Field Company(2022ZD01-02).
文摘Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage mechanisms.In this study,the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage experiments.On the basis of these experiments,a numerical simulation model(based on the special seepage mechanism)and an inverse dynamic reserve algorithm(with different equivalent drainage areas)were developed.The well spacing ranges of Classes I,II,and III wells in the Q gas field are determined to be 802–1,000,600–662,and 285–400 m,respectively,with their average ranges as 901,631,and 342.5 m,respectively.By considering both the pairs of parallel well groups and series well groups as examples,the reliability of the calculation results is verified.It is shown that the combination of the two models can reduce errors and provide accurate results.
文摘Mr. Chairman, distinguished colleagues and vips, ladies and gentlemen, It is a great pleasure, also a privilege for me to address this august body which is a high-level gathering attended by top experts of the world and practitioners with authority in management, operational, business matters in both air and space utilization and their legal aspects. Your presence will undoubtedly increase the brilliance of
文摘This paper discusses the urgency to further develop China’s space technological industry;analyzes the gaps between China and other advanced countries in space industry,including technological level,development scale,application scope and investment;describes the current severe situation that the China’s space industry is faced with and proposes the overall objective,guiding principles and major tasks of China’s space technological sector in the Ninth-Five Year Plan and the coming decade.Finally,it proposes some policies and effective measures to speed up the development of China’s space industry to meet the challenge in the 21st century.
文摘Now the China National Astronau-tics Industry Corporation is devcting more efforts to narrowing the gaps and has also begun research into manned satellites,which it hopes will be real-ized by the end of this century.
文摘China’s space cause is based on the development of missile technology. In the 1950s, new China, which was just founded, decided to keep pace with the jet technology times, to begin developing missile and rocket science and technology, and to establish China’s new space scientific and technological industry.
文摘For China,at the turn of the century,how to keep the position of the space power,how to stimulate the enthusiasm of the space technicians and how to keep pace with the world space technology,all of these questions lie ahead of the Chinese people.So we may say China’s space industry now is in the key stage.If the space industry draws great attention from the central government and the people of the country,it will have a brilliant future in the 21st century.We should put our eyes on the 21st century and prepare to explore space resources.It is difficult for us to keep pace with the times if we do not explore space resources and try to earn "the money in space".
基金This paper is supported by National Natural Science Foundation of China(Grant Nos.41661109,4261043)Guangxi Science and Technology Base and Talent Special Project(Grant No.Guike AD19245041)Nanning Normal University Doctoral Research Project(Grant No.0819-2019L07).
文摘By reviewing the theories and methods of resource and environmental carrying capacity evaluation and suitability evaluation of land and space development,it provides theoretical and technical support for rational layout and optimization of land and space development pattern.From the aspects of resource carrying capacity,environmental carrying capacity,the importance of ecological protection,the suitability of agricultural production,and the suitability of urban construction,we sort out domestic and foreign documents.The evaluation of resource carrying capacity has changed from single-factor evaluation to multi-factor comprehensive evaluation.At present,the optimization of land use pattern based on the“three-generation”space is still under exploration,it is not enough to systematize and summarize the thought of optimizing the spatial pattern of the national territory.The theoretical framework,model,method and index of“dual evaluation”of territorial space need to be improved continuously,it also needs the scientific analysis and cognition from the natural direction to the human location direction and the spatial equilibrium state as the new driving force.
基金supported by the National Natural Science Foundation of China (Grant No. 31400540, 31300538)
文摘Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understanding the ecological process of restored vegetation is quite important for ecosystem reconstruction. Distinguishing stand development stages and analyzing the dynamic spatial patterns could provide insights into significant community coexistence mechanisms. In the present study, eight permanent study areas were established according to the substituting space for time method in Changbai Mountains of north-eastern China. The optimal division method was used to quantify the successional series into different stand development stages, and the point pattern analysis method(L(r) function) was used to analyse the dynamic changes in spatial patterns and interspecific associations. Our results suggested that:(1) The stand development process was divided into five stages: the first three stages were poplar-birch secondary forests in different stages of recovery, the fourth stage was thespruce-fir mixed forest, and the last stage was the primary broadleaf-Korean pine forest;(2) The spatial pattern showed an aggregated distribution at a small scale and changed to a random distribution as the scale increased in poplar-birch secondary forests, but the spatial pattern appeared to be randomly distributed in spruce-fir mixed forest and broadleafKorean pine forest;(3) The interspecific associations between pioneer species and climax species changed from negative to positive among the different stand stages, and environmental resources were shared among these species. Interspecific differences in shade tolerance among the tree species were key determinants of forest dynamics and structure. Our study is vital to the understanding of the forest development;thus, the spatial change features should receive greater attention when forest management is being planned and restoration strategies are being developed for the Changbai Mountains.
文摘In 1993, China Aerospace Corporation(CASC) announced that it would give priority to the development of satellites and their applications, automobiles and components, computers and their applications, and regard them as its three-pillar industries, which was "a historic and significant strategic decision" said Mr. Liu Jiyuan, the president of CASC. New and
文摘1 Introduction The explosive growth of the global commercial space industry has brought low-Earth orbit(LEO)satellite constellation programs,such as Starlink and Qianfan,to a pivotal stage in the evolution of space development toward commercialization.1 Traditional space missions have stringent requirements for mission risk and payload mass,while commercial satellite design emphasizes economic viability.2 This systemic transformation has not only redefined the operational framework of aerospace engineering but also opened critical pathways for the spatial application of emerging photovoltaic technologies.Perovskite solar cells(PSCs),endowed with high specific power and cost-effectiveness,have demonstrated competitive potential against silicon-based counterparts in terrestrial applications.3 Crucially,their application prospects are particularly promising in the space domain,where device mass,power density,and cost efficiency are critical design constraints.
基金Supported by the 11th 5-year Scientific Supporting Project Fund of the Ministry of Science and Technology(2006BAJ01A12-06)the 11th 5-years Planning Philosophy and Social Science Project of Sichuan Province(SC06B014)~~
文摘This article elaborated the characteristics of settlement shape in detail with examples. Aiming at the negative effects on settlement shape by construction, we put forward some measures, such as respect for ecological environment, selection mode of space development, protection of historical features, and excavation of culture connotation, so as to realize the protection of settlement shape.
