Freezing–thawing indices serve as a comprehensive indicator of both the duration of the freezing/thawing periods and the degree of cold and heat in a given region.In-depth analysis of the freezing-thawing indices not...Freezing–thawing indices serve as a comprehensive indicator of both the duration of the freezing/thawing periods and the degree of cold and heat in a given region.In-depth analysis of the freezing-thawing indices not only enables the prediction of permafrost distribution and its dynamic changes,but also facilitates the assessment of damage risk to infrastructure under freeze-thaw action.In this paper,the air/ground freezing–thawing indices from 1987 to 2017,based on daily temperature observations from meteorological stations along the China–Nepal Highway(CNH),were calculated,and their spatial and temporal variation patterns were analyzed.The results showed that:(1)Both mean annual air temperature and mean annual ground surface temperature along the CNH fluctuated upward,with climate tendency rates of 0.43 and 0.52.C·(10a)~(-1),respectively;(2)The number of days with negative air temperature and ground temperature showed fluctuated downward,with change rates of-8.6 and-8.3 d·(10a)~(-1),respectively;(3)The ranges of air freezing index,air thawing index,ground freezing index,and ground thawing index over the years were 157.05-458.88°C·d,2034.20-2560.73°C·d,108.78-396.83°C·d,and 3515.25-4288.67°C·d,respectively.The climate tendency rates were-5.42,10.22,-6.79,and 12.14.C·d·a-1,respectively,showing a general warming trend;(4)The air freezing index,ground freezing index,and ground thawing index changed abruptly in 1999,2000,and 2002,respectively,evincing significant changes after 2002.The research results can provide a basis for the risk assessment of freezing–thawing erosion and the prevention and control of permafrost engineering diseases along the CNH.展开更多
Fine spatial and temporal resolution land surface temperature(LST)data are of great importance for various researches and applications.Spatio-temporal fusion provides an important solution to obtain fine spatio-tempor...Fine spatial and temporal resolution land surface temperature(LST)data are of great importance for various researches and applications.Spatio-temporal fusion provides an important solution to obtain fine spatio-temporal resolution LST.For example,100-m,daily LST data can be created by fusing 1-km,daily Moderate Resolution Imaging Spectroradiometer(MODIS)LST with 100-m,16-day Landsat LST data.However,the quality of MODIS LST products has been decreasing noticeably in recent years,which has a great impact on fusion accuracy.To address this issue,this paper proposes to use Visible Infrared Imaging Radiometer Suite(VIIRS)LST to replace MODIS LST in spatio-temporal fusion.Meanwhile,to cope with the data discrepancy caused by the large difference in overpass time between VIIRS LST and Landsat LST,a spatio-temporal fusion method based on the Restormer(RES-STF)is proposed.Specifically,to effectively model the differences between the 2 types of data,RES-STF uses Transformer modules in Restormer,which combines the advantages of convolutional neural networks(CNN)and Transformer to effectively capture both local and global context in images.In addition,the calculation of self-attention is re-designed by concatenating CNN to increase the efficiency of feature extraction.Experimental results on 3 areas validated the effectiveness of RES-STF,which outperforms one non-deep learning-and 3 deep learning-based spatio-temporal fusion methods.Moreover,compared to MODIS LST,VIIRS LST data contain richer spatial texture information,leading to more accurate fusion results,with both RMSE and MAE reduced by about 0.5 K.展开更多
Research on human motion prediction has made significant progress due to its importance in the development of various artificial intelligence applications.However,effectively capturing spatio-temporal features for smo...Research on human motion prediction has made significant progress due to its importance in the development of various artificial intelligence applications.However,effectively capturing spatio-temporal features for smoother and more precise human motion prediction remains a challenge.To address these issues,a robust human motion prediction method via integration of spatial and temporal cues(RISTC)has been proposed.This method captures sufficient spatio-temporal correlation of the observable sequence of human poses by utilizing the spatio-temporal mixed feature extractor(MFE).In multi-layer MFEs,the channel-graph united attention blocks extract the augmented spatial features of the human poses in the channel and spatial dimension.Additionally,multi-scale temporal blocks have been designed to effectively capture complicated and highly dynamic temporal information.Our experiments on the Human3.6M and Carnegie Mellon University motion capture(CMU Mocap)datasets show that the proposed network yields higher prediction accuracy than the state-of-the-art methods.展开更多
To solve the problems of rural revitalization performance research,a quantitative model of non-oriented range-wide EBM(Epsilon-Based Measure)-GML(Global-Malmquist)based on VRS(Variable Returns to Scale)conditions incl...To solve the problems of rural revitalization performance research,a quantitative model of non-oriented range-wide EBM(Epsilon-Based Measure)-GML(Global-Malmquist)based on VRS(Variable Returns to Scale)conditions including non-desired outputs is constructed.A comprehensive spatio-temporal heterogeneity research index system of rural revitalization performance is also constructed.Taking the typical rural in Chifeng City as an example,the panel data from 2016-2020 are selected for empirical analysis,the conclusions and countermeasures are suggested as follows:1)In general,the rural revitalization performance of Chifeng City increases significantly during the five-year period,with significant spatio-temporal heterogeneity.The overall analysis shows that the overall performance value of rural revitalization in Chifeng City is 0.683 from 2016 to 2020.The highest performance value is 1 and the lowest performance value is 0.389.The performance growth rate increases year by year,with an average annual growth rate of 4.46%.2)From 2016 to 2020,the GML index of rural revitalization performance in Chifeng City is 1.174,showing an increasing trend.Based on the range of change of GML index,Chifeng City can be classified into three types:Continuous improvement,fluctuating improvement and fluctuating decline.3)Niujiayingzi,Guandongche,Zhaidamu,and Qiangangtai rural have the highest degree of technological progress.展开更多
Aims and scope GeoSus encourages wider analysis and innovative thinking about global and regional sustainability by bridging and synthesising natural and human sciences.GeoSus welcomes original,high-quality research a...Aims and scope GeoSus encourages wider analysis and innovative thinking about global and regional sustainability by bridging and synthesising natural and human sciences.GeoSus welcomes original,high-quality research articles,review articles,short communications,technical comments,perspective articles and editorials on the following themes:●Geographical Processes:Interactions with and between water,soil,atmosphere and the biosphere and their spatio-temporal variations.展开更多
The advent of high-resolution black hole imaging—most notably by the Event Horizon Telescope(EHT)—has propelled black hole physics into a new observational regime[1].However,most theoretical interpretations remain a...The advent of high-resolution black hole imaging—most notably by the Event Horizon Telescope(EHT)—has propelled black hole physics into a new observational regime[1].However,most theoretical interpretations remain anchored in stationary,time-averaged general relativistic magnetohydrodynamic(GRMHD)simulations within the Kerr paradigm,often neglecting dynamic accretion structures and potential deviations from general relativity[2].展开更多
Combining the science of complexity with ore geology, the author puts forward a new theory of metallogenesis: “complexity and self organized criticality of metallogenic dynamic systems”, and three fundamental theor...Combining the science of complexity with ore geology, the author puts forward a new theory of metallogenesis: “complexity and self organized criticality of metallogenic dynamic systems”, and three fundamental theories are raised for it. The ore genesis and regularity of ore formation of four metallogenic districts around the Yangtze craton in China are studied with this theory. It is found that “metallogenic districts of Yangtze cratonic rim are all at the edge of chaos”. This proposition is expounded by four determinative criteria of the edge of chaos for metallogenic districts of Yangtze cratonic rim.展开更多
Deep seated magmatic liquation injection deposits form a major type of magmatic sulfide deposit in China. The reserves of nickel and copper in this type of deposit may attain several hundred thousand tons (e.g.Hongq...Deep seated magmatic liquation injection deposits form a major type of magmatic sulfide deposit in China. The reserves of nickel and copper in this type of deposit may attain several hundred thousand tons (e.g.Hongqi 7 and Karatunggu) to nearly ten million tons (e.g.Jinchuan). Those deposits can be classified as large or superlarge deposits. The ore grade is relatively high, commonly with w (Ni)>1 %. The mineralized intrusions are small in size, generally only 0.0 n km 2 to 0. n km 2, with the largest one not exceeding a few km 2. Before intruding, the primary magmas have undergone liquation and partial crystallization at depth; as a result, the magmas have partitioned into barren magma, ore bearing magma, ore rich magma and ore magma, which then ascended and injected into the present locations once or multiple times, to form ore deposits. The above mentioned mineralizing process is known as deep seated magmatic liquation injection mineralization. The volume of the barren magma is generally much larger than those of the ore bearing magma, ore rich magma and ore magma. In the ascending process, most of the barren magma intruded into different locations or outpoured onto the ground surface, forming intrusions or lava flows. The rest barren magma, ore bearing magma, ore rich magma and ore magma may either multiple times inject into the same place in which rocks and ores are formed or separately inject into different spaces to form rocks and ores. Such deep seated magmatic liquation injection deposits have a much smaller volume, greater ore potential and higher ore grade than those of in situ magmatic liquation deposits. Consequently, this mineralizing process leads to the formation of large deposits in small intrusions.展开更多
The author puts forward the proposition of Complexity and Self Organized Criticality of Solid Earth System in the light of: (1) the science of complexity studies the mechanisms of emergence of complexity and is...The author puts forward the proposition of Complexity and Self Organized Criticality of Solid Earth System in the light of: (1) the science of complexity studies the mechanisms of emergence of complexity and is the science of the 21st century, (2) the study of complexity of the earth system would be one of the growing points occupying a strategic position in the development of geosciences in the 21st century. By the proposition we try to cogitate from a new viewpoint the ancient yet ever new solid earth system. The author abstracts the fundamental problem of the solid earth system from the essence of the generalized geological systems and processes which reads: the complexity and self organized criticality of the global nature, structure and dynamical behavior of the whole solid earth system emerging from the multiple coupling and superposition of non linear interactions among the multicomponents of the earths material and the multiple generalized geological (geological, geophysical, and geochemical) processes . Starting from this cognizance the author proposes eight major themes and the methodology of researches on the complexity and self organized criticality of the solid earth system.展开更多
Visible light communication plays an essential role in the next-generation 6G network due to its extremely high bandwidth and ultrafast transmission speed.Incorporating position sensing functionality into the communic...Visible light communication plays an essential role in the next-generation 6G network due to its extremely high bandwidth and ultrafast transmission speed.Incorporating position sensing functionality into the communication system is highly desired for achieving target-oriented beamforming and accommodating high-speed data service.However,an efficient solution to integrated sensing and light communication remains challenging.Here,we demonstrate an integrated system that concurrently accomplishes high-precision sensing and high-speed data transmission by spatio-temporal modulation of the illumination and computational reconstruction.We developed a compressive angular projection imaging scheme to achieve rapid three-dimensional localization with high resolution,and a jointly optimized waveform design ensures slight sacrifice in the transmission data rate on the integrated system.We experimentally demonstrated a resolving resolution of 1 mm in lateral and 4 cm in depth within 0.6 m×0.6 m×0.6 m volume over 2 m distance at the sensing speed of 39 Hz in both static and dynamic conditions.This capability enables adaptive beamforming,which significantly enhances the data rate by 184%to permit errorless transmission of high-throughput virtual reality videos.Our work offers a promising route for intelligent wireless light communication systems with spatial perception capability,presenting the possibility of cable-free,immersive virtual reality experiences.展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2021QZKK0202)Shaanxi Provincial Youth Science and Technology Rising Star Project(No.2022KJXX-85)+3 种基金Key Scientific Research Project of Shaanxi Provincial Department of Education(No.22JS041)Youth Innovation Team Research Project of Shaanxi Provincial Department of Education(Nos.22JP099,21JP137)The Youth Innovation Team of Shaanxi Universitiesthe Support Program for Outstanding Young Talents of Shaanxi Universities(Dr.Tao Luo)。
文摘Freezing–thawing indices serve as a comprehensive indicator of both the duration of the freezing/thawing periods and the degree of cold and heat in a given region.In-depth analysis of the freezing-thawing indices not only enables the prediction of permafrost distribution and its dynamic changes,but also facilitates the assessment of damage risk to infrastructure under freeze-thaw action.In this paper,the air/ground freezing–thawing indices from 1987 to 2017,based on daily temperature observations from meteorological stations along the China–Nepal Highway(CNH),were calculated,and their spatial and temporal variation patterns were analyzed.The results showed that:(1)Both mean annual air temperature and mean annual ground surface temperature along the CNH fluctuated upward,with climate tendency rates of 0.43 and 0.52.C·(10a)~(-1),respectively;(2)The number of days with negative air temperature and ground temperature showed fluctuated downward,with change rates of-8.6 and-8.3 d·(10a)~(-1),respectively;(3)The ranges of air freezing index,air thawing index,ground freezing index,and ground thawing index over the years were 157.05-458.88°C·d,2034.20-2560.73°C·d,108.78-396.83°C·d,and 3515.25-4288.67°C·d,respectively.The climate tendency rates were-5.42,10.22,-6.79,and 12.14.C·d·a-1,respectively,showing a general warming trend;(4)The air freezing index,ground freezing index,and ground thawing index changed abruptly in 1999,2000,and 2002,respectively,evincing significant changes after 2002.The research results can provide a basis for the risk assessment of freezing–thawing erosion and the prevention and control of permafrost engineering diseases along the CNH.
基金supported by the National Natural Science Foundation of China under grants 42171345 and 42222108.
文摘Fine spatial and temporal resolution land surface temperature(LST)data are of great importance for various researches and applications.Spatio-temporal fusion provides an important solution to obtain fine spatio-temporal resolution LST.For example,100-m,daily LST data can be created by fusing 1-km,daily Moderate Resolution Imaging Spectroradiometer(MODIS)LST with 100-m,16-day Landsat LST data.However,the quality of MODIS LST products has been decreasing noticeably in recent years,which has a great impact on fusion accuracy.To address this issue,this paper proposes to use Visible Infrared Imaging Radiometer Suite(VIIRS)LST to replace MODIS LST in spatio-temporal fusion.Meanwhile,to cope with the data discrepancy caused by the large difference in overpass time between VIIRS LST and Landsat LST,a spatio-temporal fusion method based on the Restormer(RES-STF)is proposed.Specifically,to effectively model the differences between the 2 types of data,RES-STF uses Transformer modules in Restormer,which combines the advantages of convolutional neural networks(CNN)and Transformer to effectively capture both local and global context in images.In addition,the calculation of self-attention is re-designed by concatenating CNN to increase the efficiency of feature extraction.Experimental results on 3 areas validated the effectiveness of RES-STF,which outperforms one non-deep learning-and 3 deep learning-based spatio-temporal fusion methods.Moreover,compared to MODIS LST,VIIRS LST data contain richer spatial texture information,leading to more accurate fusion results,with both RMSE and MAE reduced by about 0.5 K.
基金supported by the National Key R&D Program of China(No.2018YFB1305200)the Natural Science Foundation of Zhejiang Province(No.LGG21F030011)。
文摘Research on human motion prediction has made significant progress due to its importance in the development of various artificial intelligence applications.However,effectively capturing spatio-temporal features for smoother and more precise human motion prediction remains a challenge.To address these issues,a robust human motion prediction method via integration of spatial and temporal cues(RISTC)has been proposed.This method captures sufficient spatio-temporal correlation of the observable sequence of human poses by utilizing the spatio-temporal mixed feature extractor(MFE).In multi-layer MFEs,the channel-graph united attention blocks extract the augmented spatial features of the human poses in the channel and spatial dimension.Additionally,multi-scale temporal blocks have been designed to effectively capture complicated and highly dynamic temporal information.Our experiments on the Human3.6M and Carnegie Mellon University motion capture(CMU Mocap)datasets show that the proposed network yields higher prediction accuracy than the state-of-the-art methods.
基金Research on Local Knowledge Mapping and Planning Application Strategies of Traditional Rural in Qinba Mountains(No.19YJAZH107)Humanities and Social Sciences Research Planning Fund,Ministry of Education,China.
文摘To solve the problems of rural revitalization performance research,a quantitative model of non-oriented range-wide EBM(Epsilon-Based Measure)-GML(Global-Malmquist)based on VRS(Variable Returns to Scale)conditions including non-desired outputs is constructed.A comprehensive spatio-temporal heterogeneity research index system of rural revitalization performance is also constructed.Taking the typical rural in Chifeng City as an example,the panel data from 2016-2020 are selected for empirical analysis,the conclusions and countermeasures are suggested as follows:1)In general,the rural revitalization performance of Chifeng City increases significantly during the five-year period,with significant spatio-temporal heterogeneity.The overall analysis shows that the overall performance value of rural revitalization in Chifeng City is 0.683 from 2016 to 2020.The highest performance value is 1 and the lowest performance value is 0.389.The performance growth rate increases year by year,with an average annual growth rate of 4.46%.2)From 2016 to 2020,the GML index of rural revitalization performance in Chifeng City is 1.174,showing an increasing trend.Based on the range of change of GML index,Chifeng City can be classified into three types:Continuous improvement,fluctuating improvement and fluctuating decline.3)Niujiayingzi,Guandongche,Zhaidamu,and Qiangangtai rural have the highest degree of technological progress.
文摘Aims and scope GeoSus encourages wider analysis and innovative thinking about global and regional sustainability by bridging and synthesising natural and human sciences.GeoSus welcomes original,high-quality research articles,review articles,short communications,technical comments,perspective articles and editorials on the following themes:●Geographical Processes:Interactions with and between water,soil,atmosphere and the biosphere and their spatio-temporal variations.
文摘The advent of high-resolution black hole imaging—most notably by the Event Horizon Telescope(EHT)—has propelled black hole physics into a new observational regime[1].However,most theoretical interpretations remain anchored in stationary,time-averaged general relativistic magnetohydrodynamic(GRMHD)simulations within the Kerr paradigm,often neglecting dynamic accretion structures and potential deviations from general relativity[2].
文摘Combining the science of complexity with ore geology, the author puts forward a new theory of metallogenesis: “complexity and self organized criticality of metallogenic dynamic systems”, and three fundamental theories are raised for it. The ore genesis and regularity of ore formation of four metallogenic districts around the Yangtze craton in China are studied with this theory. It is found that “metallogenic districts of Yangtze cratonic rim are all at the edge of chaos”. This proposition is expounded by four determinative criteria of the edge of chaos for metallogenic districts of Yangtze cratonic rim.
文摘Deep seated magmatic liquation injection deposits form a major type of magmatic sulfide deposit in China. The reserves of nickel and copper in this type of deposit may attain several hundred thousand tons (e.g.Hongqi 7 and Karatunggu) to nearly ten million tons (e.g.Jinchuan). Those deposits can be classified as large or superlarge deposits. The ore grade is relatively high, commonly with w (Ni)>1 %. The mineralized intrusions are small in size, generally only 0.0 n km 2 to 0. n km 2, with the largest one not exceeding a few km 2. Before intruding, the primary magmas have undergone liquation and partial crystallization at depth; as a result, the magmas have partitioned into barren magma, ore bearing magma, ore rich magma and ore magma, which then ascended and injected into the present locations once or multiple times, to form ore deposits. The above mentioned mineralizing process is known as deep seated magmatic liquation injection mineralization. The volume of the barren magma is generally much larger than those of the ore bearing magma, ore rich magma and ore magma. In the ascending process, most of the barren magma intruded into different locations or outpoured onto the ground surface, forming intrusions or lava flows. The rest barren magma, ore bearing magma, ore rich magma and ore magma may either multiple times inject into the same place in which rocks and ores are formed or separately inject into different spaces to form rocks and ores. Such deep seated magmatic liquation injection deposits have a much smaller volume, greater ore potential and higher ore grade than those of in situ magmatic liquation deposits. Consequently, this mineralizing process leads to the formation of large deposits in small intrusions.
文摘The author puts forward the proposition of Complexity and Self Organized Criticality of Solid Earth System in the light of: (1) the science of complexity studies the mechanisms of emergence of complexity and is the science of the 21st century, (2) the study of complexity of the earth system would be one of the growing points occupying a strategic position in the development of geosciences in the 21st century. By the proposition we try to cogitate from a new viewpoint the ancient yet ever new solid earth system. The author abstracts the fundamental problem of the solid earth system from the essence of the generalized geological systems and processes which reads: the complexity and self organized criticality of the global nature, structure and dynamical behavior of the whole solid earth system emerging from the multiple coupling and superposition of non linear interactions among the multicomponents of the earths material and the multiple generalized geological (geological, geophysical, and geochemical) processes . Starting from this cognizance the author proposes eight major themes and the methodology of researches on the complexity and self organized criticality of the solid earth system.
基金National Key Research and Development Program of China(2023YFB2804701)National Natural Science Foundation of China(62401156,61925104,62201157,62231018)。
文摘Visible light communication plays an essential role in the next-generation 6G network due to its extremely high bandwidth and ultrafast transmission speed.Incorporating position sensing functionality into the communication system is highly desired for achieving target-oriented beamforming and accommodating high-speed data service.However,an efficient solution to integrated sensing and light communication remains challenging.Here,we demonstrate an integrated system that concurrently accomplishes high-precision sensing and high-speed data transmission by spatio-temporal modulation of the illumination and computational reconstruction.We developed a compressive angular projection imaging scheme to achieve rapid three-dimensional localization with high resolution,and a jointly optimized waveform design ensures slight sacrifice in the transmission data rate on the integrated system.We experimentally demonstrated a resolving resolution of 1 mm in lateral and 4 cm in depth within 0.6 m×0.6 m×0.6 m volume over 2 m distance at the sensing speed of 39 Hz in both static and dynamic conditions.This capability enables adaptive beamforming,which significantly enhances the data rate by 184%to permit errorless transmission of high-throughput virtual reality videos.Our work offers a promising route for intelligent wireless light communication systems with spatial perception capability,presenting the possibility of cable-free,immersive virtual reality experiences.
