This article aims to provide a comprehensive analysis of the role and development prospects of direct satellite-to-phone technology in the global communication landscape.It explores the importance,current development ...This article aims to provide a comprehensive analysis of the role and development prospects of direct satellite-to-phone technology in the global communication landscape.It explores the importance,current development status,key technical challenges,future directions,and countermeasures of this technology from multiple dimensions.The article explains the significance and necessity of direct satellite-to-phone technology in the global communication field,discusses its development background and importance as one of the key technologies in the 6G era,and outlines the research objectives,methodology,and structure of the paper.Additionally,the article reviews and analyzes the development history of direct satellite-to-phone technology on a global scale,discusses the key technical points in achieving this technology,and predicts its potential role and development direction in future communication systems from the perspective of 6G network architecture.It also explores new application scenarios and service models that may emerge from technological advancements,as well as their impact on future communication networks.The development history of direct satellite-to-phone technology and its role in current and future communication networks are emphasized,highlighting its value in promoting global communication infrastructure construction.The article also proposes improvement suggestions for existing issues and points out future research directions.展开更多
Gemstones have fascinated mankind forever,and people traveled far to find them.The Silk Road is one of the most traditional trade routes in the middle ages that was used to bring the precious stones to the European ma...Gemstones have fascinated mankind forever,and people traveled far to find them.The Silk Road is one of the most traditional trade routes in the middle ages that was used to bring the precious stones to the European market.Later,emeralds from Colombia were shipped via the ocean to the Old World.展开更多
Family medicine is a primary care specialty created in 1969 in the United States in response to concerns that specialization in medicine was leading to fragmented and depersonalized care. Family physicians engage in a...Family medicine is a primary care specialty created in 1969 in the United States in response to concerns that specialization in medicine was leading to fragmented and depersonalized care. Family physicians engage in a broad spectrum of medical care services, but the majority of their work is performed in ambulatory offices where they provide primary care for adults and children. Obstetrics and hospital care were once considered key components of family medicine, but many family doctors have been dropping these services from their scope of care as medical care in the U.S. has organized into larger multi-specialty group. However, in rural areas where family physicians are the most common type of physicians, physicians often continue to provide these services. Education of family physicians consists of medical school followed by three year of post-medical school residency training. This training occurs in a wide variety of hospitals including rural training tracks.Medical educators in the field of family medicine often provide fundamental teaching for all students, but nearly all schools offer a dedicated family medicine clinical experience during students' education. Research is a less common role for academic family medicine doctors, although many do engage in scholarship that is often focused on health care delivery and health policy.Future challenges to family medicine include how to train family doctors for a new organization model of care delivery that centers on a team approach to care, and whether training in obstetrics and hospital medicine should still be emphasized when most physicians do not engage in these types of clinical activities.展开更多
Hydropower resources in river basins are typically developed in a cascade manner. The cascade hydropower stations use water from the same river; in a sense, they form a cluster of hydropower stations which are linked ...Hydropower resources in river basins are typically developed in a cascade manner. The cascade hydropower stations use water from the same river; in a sense, they form a cluster of hydropower stations which are linked together by the river stream. The dispatch and management of the cascade hydropower stations in a river basin differ from those of an ordinary single hydropower station. Without doubt, unified dispatch can facilitate the full harnessing of hydraulic resources and is in a better position to fulfill the objectives in the development of river basin. As a result, more and more river-basin cascade power stations around the world implement unif ied dispatching.展开更多
Yesterday,Lectra,a leading supplier of industrial intelligent technology solutions for the fashion,automotive,and furniture industries,successfully held the Valia Fashion new product launch event in Shanghai.Numerous ...Yesterday,Lectra,a leading supplier of industrial intelligent technology solutions for the fashion,automotive,and furniture industries,successfully held the Valia Fashion new product launch event in Shanghai.Numerous industry leaders,experts,scholars,and media participated in this event to communicate the future trends of fashion manufacturing and witness the heavyweight release of a new intelligent digital platform-Valia Fashion.The launch of this platform is not only an important milestone for Lectra to promote intelligent upgrading in the industry,but also marks a new era of fashion manufacturing centered on data-driven,collaborative efficiency,and sustainable development.展开更多
This paper provides a comprehensive review of the current status, advancements, and future prospects of humanoid robots, highlighting their significance in driving the evolution of next-generation industries. By analy...This paper provides a comprehensive review of the current status, advancements, and future prospects of humanoid robots, highlighting their significance in driving the evolution of next-generation industries. By analyzing various research endeavors and key technologies, encompassing ontology structure,control and decision-making, and perception and interaction, a holistic overview of the current state of humanoid robot research is presented. Furthermore, emerging challenges in the field are identified, emphasizing the necessity for a deeper understanding of biological motion mechanisms, improved structural design,enhanced material applications, advanced drive and control methods, and efficient energy utilization. The integration of bionics, brain-inspired intelligence, mechanics, and control is underscored as a promising direction for the development of advanced humanoid robotic systems. This paper serves as an invaluable resource, offering insightful guidance to researchers in the field,while contributing to the ongoing evolution and potential of humanoid robots across diverse domains.展开更多
This study analyzed the changes in precipita- tion over summer and autumn across the Yunnan region of China, and undertook a composite analysis of the atmo- spheric circulations in the troposphere, which included an a...This study analyzed the changes in precipita- tion over summer and autumn across the Yunnan region of China, and undertook a composite analysis of the atmo- spheric circulations in the troposphere, which included an analysis of the interannual and interdecadal variations. This paper examines in detail the circulation backgrounds of the wet and dry periods in summer and autumn and their correlations with the sea surface temperature. The results indicated that the summer and autumn precipitation across Yunnan has significantly decreased over the past 50 years. Furthermore, since the beginning of the century, the summer and autumn precipitation cycle has been in a low precipitation phase. The overlap of two extremely low rain phases has caused frequent droughts in the region. In addition, the atmospheric circulation fields during these wet and dry periods are very different. These are mainly shown as a meridional wind anomaly in eastern China in the low atmosphere, as a cross-equatorial airflow anomaly, a tropical zonal wind anomaly over the Indian Ocean, and as a related South Asia High and Western Pacific Subtropical High. Further analysis suggested that the SST over the Indian Ocean and the Pacific warm pool critically affect the anomalous summer and autumn precipitation over Yunnan by impacting the monsoon circulations. Future projections for greenhouse gas wann- ing suggest a potential anomalous circulation background between 2010 and 2020 which may result in less precipitation during the wet season or even drought events across the Yunnan region.展开更多
In weather sciences,the two specific terms“storm”and“cyclone”frequently appear in literature and usually refer to the violent nature of a number of weather systems characterized by central low pressure,strong wind...In weather sciences,the two specific terms“storm”and“cyclone”frequently appear in literature and usually refer to the violent nature of a number of weather systems characterized by central low pressure,strong winds,large precipitation amounts in the form of rain,freezing rain,or snow,as well as thunder and lightning.But what is the connection between these two specific terms?In this paper,the historic evolutions of the terms“storm”and“cyclone”are reviewed from the perspective of weather science.The earliest recorded storms in world history are also briefly introduced.Then,the origin of the term“meteorological bomb”,which is the nickname of the“explosive cyclone”is introduced.Later,the various definitions of explosive cyclones given by several researchers are discussed.Also,the climatological features of explosive cyclones,as well as the future trends of explosive cyclones under global climate change,are discussed.展开更多
Since 2014, the development of the China-India relationship has followed a trend of starting high and ending low. The China-India relationship warmed up rapidly in the first two years, which nevertheless failed to bri...Since 2014, the development of the China-India relationship has followed a trend of starting high and ending low. The China-India relationship warmed up rapidly in the first two years, which nevertheless failed to bring about a substantial breakthrough in their bilateral relations, as India's strategic doubts about China and their differences of interests on numerous issues still pose difficulties.展开更多
According to the viewpoint of historical materialism,the economic base determines the superstructure.In the long process of its development,capitalism has not only shaped political and economic institutions within cou...According to the viewpoint of historical materialism,the economic base determines the superstructure.In the long process of its development,capitalism has not only shaped political and economic institutions within countries but also profoundly impacted the development and transition of the world order.However,since the international financial crisis展开更多
Acute lung injury (ALI) is one of the most important clinical respiratory diseases, which can easily lead to acute respiratory failure or multiple organ failure, and the mortality is very high. In this paper, the path...Acute lung injury (ALI) is one of the most important clinical respiratory diseases, which can easily lead to acute respiratory failure or multiple organ failure, and the mortality is very high. In this paper, the pathogenesis, treatment trend and future research trend of acute lung injury were studied.展开更多
Post-harvest waste of fruits and vegetables has rapidly become a serious global issue within the past few decades.this waste,which ranges from 40%to 44%,is influenced by various physical,social,and biological factors ...Post-harvest waste of fruits and vegetables has rapidly become a serious global issue within the past few decades.this waste,which ranges from 40%to 44%,is influenced by various physical,social,and biological factors in the food and beverage and agricultural sectors.Such waste occurs across the supply chain,from the initial stages of crop cultivation to the consumption of the products.as a result of that,the food becomes unsafe and unsuitable for consumption.addressing solutions to reduce the waste generated by fruits and vegetables would pave the way to reach sustainable solutions for the negative concerns based on food security,food safety,economic sustainability,and adverse environmental impacts.Numerous methods,both conventional and novel,have been employed to minimize post-harvest waste.Scientists today aim to make significant strides in minimizing waste generated from the agricultural fields relating to fruits and vegetables by integrating both conventional and novel technologies.this strategy directs the crucial development of sustainable solutions for critical issues based on food security and consumer perception.traditional food preservation techniques include refrigeration,ionizing radiation,fruit and vegetable coating technologies,chemical treatments,the application of fungicides,ultrasound technology,ozone treatments,pulsed electric fields,and cold plasma technology.these can be categorized as either thermal or non-thermal applications.Non-thermal preservation methods have gained popularity over thermal methods due to their advantages in large-scale commercial applications.currently,the industry is exploring novel approaches like nanotechnology,which surpasses many non-thermal methods in effectiveness,safety,and quality.Within the food and beverage packaging realm,nanotechnology is employed in various ways,such as bio-based packaging,active packaging,smart packaging,and enhanced packaging.展开更多
Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem.To curb the continued loss of wetlands globally,international organizations and many count...Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem.To curb the continued loss of wetlands globally,international organizations and many countries have taken a series of major conservation and restoration measures.This work reviews these wetland conservation and restoration measures,interprets China’s wetland conservation and restoration management policies,and proposes that future research on wetland resources in China should be conducted from the aspects of international frontiers and national strategic plans,socioeconomics,and smart services.The results show that the 27 International Wetlands Days from 1997 to 2023 provided new goals and tasks for the protection and management of wetlands.The important topics and outcomes of the 14 Conferences of the Contracting Parties to the Convention on Wetlands from 1980 to 2022 provided new directions and new challenges for wetland development.In the future,we should enhance wetland ecological functions,promote sustainable wetland development,and overcome the technical bottleneck of fragile wetland ecosystem restoration.From 1992 to 2022,China embarked on a new phase of wetland protection and restoration.The overall experience of wetland protection and restoration in China has been formed through national strategic deployment,legal policy establishment,and project planning and implementation.The needs to provide for and plan the long-term protection of wetlands at the national level,to innovate restoration and management techniques and application systems,and to effectively address the complex issues of wetland protection and restoration through collaborative division of labor among multiple departments were emphasized.Research on the future trends of wetlands should be directed towards the exploration and practice of the United Nations Sustainable Development Goals and several international conventions in support of sustainable wetland development.Wetland protection,restoration,and management services should be promoted for national strategic needs and local,high-quality social and economic development.In addition,research on cross-integration and academic innovation should be enhanced for disciplinary development,global supervision,comprehensive assessment,and smart decision making.展开更多
Residual stress is one of the main factors affecting the mechanical properties of materials, such as their strength, plasticity and surface integrity. For instance, tensile stress conditions can adversely affect mater...Residual stress is one of the main factors affecting the mechanical properties of materials, such as their strength, plasticity and surface integrity. For instance, tensile stress conditions can adversely affect material performance or component life, while compressive stress conditions can improve material fatigue strength. During the processing of integrated aviation structures, machining deformation caused by residual stress has become one of the most prominent manufacturing problems. Therefore, it is very important to measure and evaluate the stress for real applications.This paper reviews the research of residual stress measurement methods over the past five years by classifying them according to the measurement methods appearing in each stage. The existing problems and difficulties of each measurement technology are summarized, and future trends are forecasted. This paper provides a reference for further in-depth study of residual stress measurement technologies.展开更多
Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-maki...Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-making. With the long-term Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS) nighttime light images, a pixel level assessment of urbanization of China from 1992 to 2013 was conducted in this study, and the spatio-temporal dynamics and future trends of urban development were fully detected. The results showed that the urbanization and urban dynamics of China experienced drastic fluctuations from 1992 to 2013, especially for those in the coastal and metropolitan areas. From a regional perspective, it was found that the urban dynamics and increasing trends in North Coast China, East Coast China and South Coast China were much more stable and significant than that in other regions. Moreover, with the sustainability estimating of nighttime light dynamics, the regional agglomeration trends of urban regions were also detected. The light intensity in nearly 50% of lighted pixels may continuously decrease in the future, indicating a severe situation of urbanization within these regions. In this study, The results revealed in this study can provided a new insight in long time urbanization detecting and is thus beneficial to the better understanding of trends and dynamics of urban development.展开更多
Based on the global distribution of land and soil quality and the world population,future trends in the agricultural use of land and soil resources are described,which will severely compromise future global food and f...Based on the global distribution of land and soil quality and the world population,future trends in the agricultural use of land and soil resources are described,which will severely compromise future global food and fiber production through the increase and the spatial changes of world population,through the loss of fertile land caused by insufficient soil management and through urbanisation and industrialization Moreover,future changes in life style and the increasing demand for food and bioenergy,trough changes in world economy,through climate change and a worldwide decrease in fresh water supply,sustainable land use for the production of food and fiber will be under threat.Until 2050 global food production must be doubled for satisfying global needs.Our scenarios should help to preview future changes,to counterbalance and to mitigate possible negative impacts,thus sustaining global food security.展开更多
文摘This article aims to provide a comprehensive analysis of the role and development prospects of direct satellite-to-phone technology in the global communication landscape.It explores the importance,current development status,key technical challenges,future directions,and countermeasures of this technology from multiple dimensions.The article explains the significance and necessity of direct satellite-to-phone technology in the global communication field,discusses its development background and importance as one of the key technologies in the 6G era,and outlines the research objectives,methodology,and structure of the paper.Additionally,the article reviews and analyzes the development history of direct satellite-to-phone technology on a global scale,discusses the key technical points in achieving this technology,and predicts its potential role and development direction in future communication systems from the perspective of 6G network architecture.It also explores new application scenarios and service models that may emerge from technological advancements,as well as their impact on future communication networks.The development history of direct satellite-to-phone technology and its role in current and future communication networks are emphasized,highlighting its value in promoting global communication infrastructure construction.The article also proposes improvement suggestions for existing issues and points out future research directions.
文摘Gemstones have fascinated mankind forever,and people traveled far to find them.The Silk Road is one of the most traditional trade routes in the middle ages that was used to bring the precious stones to the European market.Later,emeralds from Colombia were shipped via the ocean to the Old World.
文摘Family medicine is a primary care specialty created in 1969 in the United States in response to concerns that specialization in medicine was leading to fragmented and depersonalized care. Family physicians engage in a broad spectrum of medical care services, but the majority of their work is performed in ambulatory offices where they provide primary care for adults and children. Obstetrics and hospital care were once considered key components of family medicine, but many family doctors have been dropping these services from their scope of care as medical care in the U.S. has organized into larger multi-specialty group. However, in rural areas where family physicians are the most common type of physicians, physicians often continue to provide these services. Education of family physicians consists of medical school followed by three year of post-medical school residency training. This training occurs in a wide variety of hospitals including rural training tracks.Medical educators in the field of family medicine often provide fundamental teaching for all students, but nearly all schools offer a dedicated family medicine clinical experience during students' education. Research is a less common role for academic family medicine doctors, although many do engage in scholarship that is often focused on health care delivery and health policy.Future challenges to family medicine include how to train family doctors for a new organization model of care delivery that centers on a team approach to care, and whether training in obstetrics and hospital medicine should still be emphasized when most physicians do not engage in these types of clinical activities.
文摘Hydropower resources in river basins are typically developed in a cascade manner. The cascade hydropower stations use water from the same river; in a sense, they form a cluster of hydropower stations which are linked together by the river stream. The dispatch and management of the cascade hydropower stations in a river basin differ from those of an ordinary single hydropower station. Without doubt, unified dispatch can facilitate the full harnessing of hydraulic resources and is in a better position to fulfill the objectives in the development of river basin. As a result, more and more river-basin cascade power stations around the world implement unif ied dispatching.
文摘Yesterday,Lectra,a leading supplier of industrial intelligent technology solutions for the fashion,automotive,and furniture industries,successfully held the Valia Fashion new product launch event in Shanghai.Numerous industry leaders,experts,scholars,and media participated in this event to communicate the future trends of fashion manufacturing and witness the heavyweight release of a new intelligent digital platform-Valia Fashion.The launch of this platform is not only an important milestone for Lectra to promote intelligent upgrading in the industry,but also marks a new era of fashion manufacturing centered on data-driven,collaborative efficiency,and sustainable development.
基金supported by the National Natural Science Foundation of China(62303457,U21A20482)Project funded by China Postdoctoral Science Foundation (2023M733737)the National Key R&D Program of China(2022YFB3303800)。
文摘This paper provides a comprehensive review of the current status, advancements, and future prospects of humanoid robots, highlighting their significance in driving the evolution of next-generation industries. By analyzing various research endeavors and key technologies, encompassing ontology structure,control and decision-making, and perception and interaction, a holistic overview of the current state of humanoid robot research is presented. Furthermore, emerging challenges in the field are identified, emphasizing the necessity for a deeper understanding of biological motion mechanisms, improved structural design,enhanced material applications, advanced drive and control methods, and efficient energy utilization. The integration of bionics, brain-inspired intelligence, mechanics, and control is underscored as a promising direction for the development of advanced humanoid robotic systems. This paper serves as an invaluable resource, offering insightful guidance to researchers in the field,while contributing to the ongoing evolution and potential of humanoid robots across diverse domains.
基金This research was supported by the National Natural Science Foundation of China （Grant Nos. 41175051 and 41101045）, and the National Science Foundation of China-Yunnan Province Joint Grant （U1133603）.
文摘This study analyzed the changes in precipita- tion over summer and autumn across the Yunnan region of China, and undertook a composite analysis of the atmo- spheric circulations in the troposphere, which included an analysis of the interannual and interdecadal variations. This paper examines in detail the circulation backgrounds of the wet and dry periods in summer and autumn and their correlations with the sea surface temperature. The results indicated that the summer and autumn precipitation across Yunnan has significantly decreased over the past 50 years. Furthermore, since the beginning of the century, the summer and autumn precipitation cycle has been in a low precipitation phase. The overlap of two extremely low rain phases has caused frequent droughts in the region. In addition, the atmospheric circulation fields during these wet and dry periods are very different. These are mainly shown as a meridional wind anomaly in eastern China in the low atmosphere, as a cross-equatorial airflow anomaly, a tropical zonal wind anomaly over the Indian Ocean, and as a related South Asia High and Western Pacific Subtropical High. Further analysis suggested that the SST over the Indian Ocean and the Pacific warm pool critically affect the anomalous summer and autumn precipitation over Yunnan by impacting the monsoon circulations. Future projections for greenhouse gas wann- ing suggest a potential anomalous circulation background between 2010 and 2020 which may result in less precipitation during the wet season or even drought events across the Yunnan region.
基金supports of National Key R&D Program of China(2022YFC3004200)National Natural Science Foundation of China(Grant Nos.42275001 and 41775042)to this study.
文摘In weather sciences,the two specific terms“storm”and“cyclone”frequently appear in literature and usually refer to the violent nature of a number of weather systems characterized by central low pressure,strong winds,large precipitation amounts in the form of rain,freezing rain,or snow,as well as thunder and lightning.But what is the connection between these two specific terms?In this paper,the historic evolutions of the terms“storm”and“cyclone”are reviewed from the perspective of weather science.The earliest recorded storms in world history are also briefly introduced.Then,the origin of the term“meteorological bomb”,which is the nickname of the“explosive cyclone”is introduced.Later,the various definitions of explosive cyclones given by several researchers are discussed.Also,the climatological features of explosive cyclones,as well as the future trends of explosive cyclones under global climate change,are discussed.
文摘Since 2014, the development of the China-India relationship has followed a trend of starting high and ending low. The China-India relationship warmed up rapidly in the first two years, which nevertheless failed to bring about a substantial breakthrough in their bilateral relations, as India's strategic doubts about China and their differences of interests on numerous issues still pose difficulties.
文摘According to the viewpoint of historical materialism,the economic base determines the superstructure.In the long process of its development,capitalism has not only shaped political and economic institutions within countries but also profoundly impacted the development and transition of the world order.However,since the international financial crisis
文摘Acute lung injury (ALI) is one of the most important clinical respiratory diseases, which can easily lead to acute respiratory failure or multiple organ failure, and the mortality is very high. In this paper, the pathogenesis, treatment trend and future research trend of acute lung injury were studied.
基金the National Research Council (NRC) Sri Lanka for granting us financial aid under NRC IDG 22-047 for completing this research project successfully
文摘Post-harvest waste of fruits and vegetables has rapidly become a serious global issue within the past few decades.this waste,which ranges from 40%to 44%,is influenced by various physical,social,and biological factors in the food and beverage and agricultural sectors.Such waste occurs across the supply chain,from the initial stages of crop cultivation to the consumption of the products.as a result of that,the food becomes unsafe and unsuitable for consumption.addressing solutions to reduce the waste generated by fruits and vegetables would pave the way to reach sustainable solutions for the negative concerns based on food security,food safety,economic sustainability,and adverse environmental impacts.Numerous methods,both conventional and novel,have been employed to minimize post-harvest waste.Scientists today aim to make significant strides in minimizing waste generated from the agricultural fields relating to fruits and vegetables by integrating both conventional and novel technologies.this strategy directs the crucial development of sustainable solutions for critical issues based on food security and consumer perception.traditional food preservation techniques include refrigeration,ionizing radiation,fruit and vegetable coating technologies,chemical treatments,the application of fungicides,ultrasound technology,ozone treatments,pulsed electric fields,and cold plasma technology.these can be categorized as either thermal or non-thermal applications.Non-thermal preservation methods have gained popularity over thermal methods due to their advantages in large-scale commercial applications.currently,the industry is exploring novel approaches like nanotechnology,which surpasses many non-thermal methods in effectiveness,safety,and quality.Within the food and beverage packaging realm,nanotechnology is employed in various ways,such as bio-based packaging,active packaging,smart packaging,and enhanced packaging.
基金National Natural Science Foundation of China,No.U21A2022,No.42071393,No.U1901219,No.42101369。
文摘Wetlands are important natural resources for humans and play an irreplaceable ecological function in the terrestrial ecosystem.To curb the continued loss of wetlands globally,international organizations and many countries have taken a series of major conservation and restoration measures.This work reviews these wetland conservation and restoration measures,interprets China’s wetland conservation and restoration management policies,and proposes that future research on wetland resources in China should be conducted from the aspects of international frontiers and national strategic plans,socioeconomics,and smart services.The results show that the 27 International Wetlands Days from 1997 to 2023 provided new goals and tasks for the protection and management of wetlands.The important topics and outcomes of the 14 Conferences of the Contracting Parties to the Convention on Wetlands from 1980 to 2022 provided new directions and new challenges for wetland development.In the future,we should enhance wetland ecological functions,promote sustainable wetland development,and overcome the technical bottleneck of fragile wetland ecosystem restoration.From 1992 to 2022,China embarked on a new phase of wetland protection and restoration.The overall experience of wetland protection and restoration in China has been formed through national strategic deployment,legal policy establishment,and project planning and implementation.The needs to provide for and plan the long-term protection of wetlands at the national level,to innovate restoration and management techniques and application systems,and to effectively address the complex issues of wetland protection and restoration through collaborative division of labor among multiple departments were emphasized.Research on the future trends of wetlands should be directed towards the exploration and practice of the United Nations Sustainable Development Goals and several international conventions in support of sustainable wetland development.Wetland protection,restoration,and management services should be promoted for national strategic needs and local,high-quality social and economic development.In addition,research on cross-integration and academic innovation should be enhanced for disciplinary development,global supervision,comprehensive assessment,and smart decision making.
基金the financial support from Science Challenge Project of China (No. TZ2016006-0103 and No.TZ2016006-0107-02)Liao Ning Revitalization Talents Program of China (No. XLYC1807230)+2 种基金Science Fund for Creative Research Groups of NSFC (No. 51621064)the Fundamental Research Funds for the Central Universities of China (No. DUT17RC(3)105)National Natural Science Foundation of China (No. 51975096)。
文摘Residual stress is one of the main factors affecting the mechanical properties of materials, such as their strength, plasticity and surface integrity. For instance, tensile stress conditions can adversely affect material performance or component life, while compressive stress conditions can improve material fatigue strength. During the processing of integrated aviation structures, machining deformation caused by residual stress has become one of the most prominent manufacturing problems. Therefore, it is very important to measure and evaluate the stress for real applications.This paper reviews the research of residual stress measurement methods over the past five years by classifying them according to the measurement methods appearing in each stage. The existing problems and difficulties of each measurement technology are summarized, and future trends are forecasted. This paper provides a reference for further in-depth study of residual stress measurement technologies.
基金Under the auspices of State Scholarship Fund of China Scholarship Council(No.201706320300)。
文摘Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-making. With the long-term Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS) nighttime light images, a pixel level assessment of urbanization of China from 1992 to 2013 was conducted in this study, and the spatio-temporal dynamics and future trends of urban development were fully detected. The results showed that the urbanization and urban dynamics of China experienced drastic fluctuations from 1992 to 2013, especially for those in the coastal and metropolitan areas. From a regional perspective, it was found that the urban dynamics and increasing trends in North Coast China, East Coast China and South Coast China were much more stable and significant than that in other regions. Moreover, with the sustainability estimating of nighttime light dynamics, the regional agglomeration trends of urban regions were also detected. The light intensity in nearly 50% of lighted pixels may continuously decrease in the future, indicating a severe situation of urbanization within these regions. In this study, The results revealed in this study can provided a new insight in long time urbanization detecting and is thus beneficial to the better understanding of trends and dynamics of urban development.
文摘Based on the global distribution of land and soil quality and the world population,future trends in the agricultural use of land and soil resources are described,which will severely compromise future global food and fiber production through the increase and the spatial changes of world population,through the loss of fertile land caused by insufficient soil management and through urbanisation and industrialization Moreover,future changes in life style and the increasing demand for food and bioenergy,trough changes in world economy,through climate change and a worldwide decrease in fresh water supply,sustainable land use for the production of food and fiber will be under threat.Until 2050 global food production must be doubled for satisfying global needs.Our scenarios should help to preview future changes,to counterbalance and to mitigate possible negative impacts,thus sustaining global food security.
