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Spatio-temporal variability in sea surface wind stress near and off the east coast of Korea 被引量:1
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作者 NAM SungHyun KIM Young Ho +1 位作者 PARK Kyung-Ae KIM Kuh 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第1期107-114,共8页
Sea surface wind stress variabilities near and off the east coast of Korea, are examined using 7 kinds of wind datasets from measurements at 2 coastal (land) stations and 2 ocean buoys,satellite scatterometer (QuikSCA... Sea surface wind stress variabilities near and off the east coast of Korea, are examined using 7 kinds of wind datasets from measurements at 2 coastal (land) stations and 2 ocean buoys,satellite scatterometer (QuikSCAT), and global reanalyzed products (ECMWF,NOGAPS,and NCEP/NCAR). Temporal variabilities are analyzed at 3 frequency bands; synoptic (2-20 d), intra-seasonal (20-90 d),and seasonal (>90 d).Synoptic and intra-seasonal variations are predominant near and off the Donghae City due to the passage of the mesoscale weather system. Seasonal variation is caused by southeastward wind stress during Asian winter monsoon. The sea surface wind stress from reanalyzed datasets.QuikSCAT and KMA-B measurements off the coast show good agreement in the magnitude and direction,which are strongly aligned with the alongshore direction.At the land-based sites,wind stresses are much weaker by factors of 3-10 due to the mountainous landmass on the east parts of Korea Peninsula.The first EOF modes(67%-70%) of wind stresses from reanalyzed and QuikSCAT data have similar structures of the strong southeastward wind stress in winter along the coast but show different curl structures at scales less than 200 km due to the orographic effects.The second EOF modes (23%-25%) show southwestward wind stress in every September along the east coast of the North Korea 展开更多
关键词 sea surface wind stress spatio-temporal variability MONSOON SEASONAL intra-seasonal synoptic band orographic effect
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Spatio-temporal Variability of Northern Hemipheric Sea Level Pressure(SLP)and Precipitation over the Mid-to-Low Reaches of the Yangtze River 被引量:13
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作者 韩雪 魏凤英 +1 位作者 Yves M.TOURRE 董文杰 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第3期458-466,共9页
The spatio-temporal variability of Northern Hemisphere Sea Level Pressure (SLP) and precipitation over the mid-to-low reaches of the Yangtze River (PMLY) is analyzed jointly using the multi-taper/singular value de... The spatio-temporal variability of Northern Hemisphere Sea Level Pressure (SLP) and precipitation over the mid-to-low reaches of the Yangtze River (PMLY) is analyzed jointly using the multi-taper/singular value decomposition method (MTM-SVD). Statistically significant narrow frequency bands are obtained from the local fractional variance (LFV) spectrum. Significant interdecadal (i.e., 16-to-18-year periods) and interannual (i.e., 3-to-6-year periods) signals are identified. Moreover, a significant quasi-biennial signal is identified but only for PMLY data. The spatial joint evolution of patterns obtained for peaks in the LFV spectrum sheds light on relationships between SLP and PMLY: the Arctic Oscillation (AO) modulates the variability of the PMLY while the interannual variability of PMLY is in phase with the Northern Atlantic Oscillation (NAO) and the Northern Pacific Oscillation (NPO). 展开更多
关键词 MTM-SVD coupled spatio-temporal characteristics
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Spatio-temporal variability of periphytic protozoa related to environment in the Niyang River,Tibet,China 被引量:1
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作者 刘海平 叶少文 +6 位作者 杨学峰 郭传波 张惠娟 范丽卿 张良松 Sovan Lek 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期489-500,共12页
The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau fiver ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and fiver ecolo... The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau fiver ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and fiver ecology. In this study, the composition, abundance, and diversity of periphytic protozoa were investigated across four seasons from 2008 to 2009 to better understand their spatio-temporal patterns and relationship to the environment. Our investigation shows that periphytic protozoa in the Niyang River contained 15 genera, belonged to Tubulinea, Alveolata, Discosea and Rhizaria, Alveolata possessed most genera, up to nine, with highest share in abundance, exceeding 50%, Difflugia and Glaucoma were dominant genera. Moreover, four diversity indices of periphytic protozoa, including species richness, total abundance, Shannon-Wiener diversity index and Pielou's evenness index, displayed a significant descending trend as the seasons continued, in the order of winter, spring, summer and autumn; with a significant difference existing between winter and summer (or autumn) for Shannon-Wiener diversity index and species richness (P〈0.05). Four of these diversity indices also presented a V-shaped pattern between the upper middle course of the Niyang River and the confluence of the Niyang River and Yarlung Zangbo River, with the lowest value occurred in the middle course of the Niyang River. However, no significant variation was found through the Niyang River (P〉0.05). In addition, canonical correlation analysis (CCA) shows that the densities of Difflugia, Glaucomais, Enchelydium, Cyphoderia, and Enchelys correlate with water temperature, alkalinity, hardness, pH, and dissolved oxygen, respectively. Lastly, the relationship between periphytic protozoa diversity and the environmental factors of the Niyang River can be predicted using classification and regression trees (CART) annalysis, which suggests that the total abundance and Shannon-Wiener diversity index would be higher when the elevation is above 3 308 m. On the other hand, the Shannon-Wiener diversity index and Pielou's evenness index would be lower when pH and ammoniacal nitrogen have lower or higher values. Finally yet importantly, close attention should be paid to periphytic protozoa and its environment to ensure sustainable development of the Niyang River ecosystem. 展开更多
关键词 Tibetan Plateau Niyang River periphytic protozoa ENVIRONMENT spatio-temporal dynamic
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Spatio-temporal Variability of Disastrous Convective Weather in China from 1961 to 2016
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作者 Feng KONG 《Asian Agricultural Research》 2019年第3期30-36,40,共8页
Based on the data of hail,gale,thunderstorm and lightning days in 2 481 stations in China from 1961 to 2016,the spatial and temporal distribution characteristics,periodicity and climate abruption characteristics of fo... Based on the data of hail,gale,thunderstorm and lightning days in 2 481 stations in China from 1961 to 2016,the spatial and temporal distribution characteristics,periodicity and climate abruption characteristics of four kinds of disastrous convective weather in China were analyzed by various mathematical statistics methods. The results showed that in time,the days of four kinds of disastrous convective weather in China decreased,and the hail and thunderstorm days were characterized by " increasing firstly and then decreasing" from 1961 to 2016. The hail,gale,thunderstorm and lightning days in China had oscillation cycles of 3-5,2-3,1-2 and 1-4 a respectively,and the hail and thunderstorm days changed suddenly in 2002 and 1992 respectively. In space,the Qinghai-Tibet Plateau and western Sichuan were the highvalue distribution areas of hail,gale and thunderstorm days. The high-value distribution areas of thunderstorm days were also distributed to the south of the Yangtze River. South China and its southwestern regions at the same latitude were the high-value distribution areas of lightning days. In terms of trend,the hail days in China showed a decreasing trend mainly in the Qinghai-Tibet Plateau. The gale days in China decreased in the east,was unchanged in the central region,and increased and decreased alternately in the west. The thunderstorm days in China increased in Tibet,North China,Chongqing,Zhejiang and northwestern Heilongjiang. The lightning days in China decreased obviously to the south of the Yangtze River. In terms of the fluctuation,the hail days fluctuated greatly in the southeast. The gale days fluctuated greatly to the east of Hu Huanyong line. The thunderstorms days in China fluctuated greatly in the northwest and slightly in the southeast. In addition to the small fluctuation in northern Xinjiang and South China,the lightning days fluctuated greatly in other regions of China. 展开更多
关键词 Disastrous WEATHER Hail-gale-thunderstorm-lightning spatio-temporal pattern Characteristic of periodic oscillation Mutation test
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The Spatio-Temporal Variability of Rainfall over the Agro-Ecological Zones of Ghana
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作者 Winifred A. Atiah Leonard K. Amekudzi +1 位作者 Emmanuel Quansah Kwasi Preko 《Atmospheric and Climate Sciences》 2019年第3期527-544,共18页
Rainfall variability plays an important role in many socio-economic activities such as food security, livelihood and farming in Ghana. Rainfall impact studies are thus very crucial for proper management of these key s... Rainfall variability plays an important role in many socio-economic activities such as food security, livelihood and farming in Ghana. Rainfall impact studies are thus very crucial for proper management of these key sectors of the country. This paper examines the seasonal and annual rainfall variability in the four agro-ecological zones of Ghana from the CHIRPS V2 rainfall time series spanning a period of 1981-2015. The rainfall indices were computed with the aid of the FClimDex package whereas the trends of these indices were further tested using the Mann Kendall trend test. The results show good agreement (r ≥ 0.7) between CHIRPS V2 and gauge in almost all portions of country although high biases were observed especially in DJF season over parts of the Northeastern (NE) portions of the country. The mean seasonal rainfall climatology over the country is observed to be in the range of 20 - 80 mm, 60 - 200 mm, 100 - 220 mm and 40 - 180 mm in DJF, MAM, JJA and SON seasons respectively with high intensities of rainfall dominating Southwestern portions of the country. The trend analysis revealed positive trends of consecutive dry days in the Transition, Forest and Coastal zones and negative trends in the Savannah zone of the country. Decreasing trends of consecutive wet days are observed over the Savannah, Transition and Coastal zones whereas increasing trends dominate the Forest zone. Savannah, Forest and Transition zones show weak increasing trends of the number of heavy rainfall days whilst weak decreasing trends are observed over the Coastal zone of the country. Similarly, weak increasing trends of the number of very heavy rainfall days are observed over all the agro-ecological zones except in the Transition zone. It is observed that the annual wet day rainfall total has increasing trend in the Savannah and Forest zones of the country whereas decreasing trends cover the remainder of the zones. The trends of these indices in the agro-ecological zones were all significant at a significant value of 0.05. This paper assessed the performance of the CHIRPS V2 rainfall data over the region and reports on the biases in seasonal rainfall amounts which are limited in previous studies. These findings have adverse impacts on rain-fed agricultural practices, water resource management and food security over the country. 展开更多
关键词 RAINFALL variability TRENDS Agro-Ecological ZONES Ghana
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Spatio-Temporal Variability of Shallow Groundwater Quality in a Hilly Red-Soil Agricultural Catchment in Subtropical Central China
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作者 Qiao Luo Yong Li +3 位作者 Yuyuan Li Xinliang Liu Runlin Xiao Jinshui Wu 《International Journal of Geosciences》 2015年第1期1-11,共11页
Groundwater quality varies not only in space but also in time. In order to analyze the spatiotemporal variety of ground water quality, the concentration of ammonium nitrogen (NH4N), nitrate nitrogen (NO3N), total nitr... Groundwater quality varies not only in space but also in time. In order to analyze the spatiotemporal variety of ground water quality, the concentration of ammonium nitrogen (NH4N), nitrate nitrogen (NO3N), total nitrogen (TN) and total phosphorus (TP) in very shallow groundwater were investigated in a red-soil catchment in subtropical central China, based on a three-dimensional kriging method. The spatio-temporal analysis demonstrated that NH4N, NO3N and TP presented strong spatio-temporal autocorrelation (with a nugget-to-sill ratio of <25%) and that TN presented a moderate spatio-temporal autocorrelation (with a nugget-to-sill ratio between 25% and 75%). According to the Chinese Groundwater Quality Standards, the ratio of areas contaminated by NH4N, NO3N, TN and TP to the whole catchment was 20.05%, 1.46%, 5.07%, 5.98%, respectively. The 3D delineation of continuously dynamic variation of contaminated area indicated that the catchment’s very shallow groundwater had a moderate contamination by NH4N, slight by TN and TP, and almost non by NO3N. Although the contaminated area was very small, only occurring in small dispersed patches, a close attention should be paid to the shallow groundwater quality because local farmers obtain their domestic drinking water directly from this shallow groundwater without any treatment prior to consuming and the potential health hazard is considerable. The findings from this study highlight the importance of surveillance of the contaminated area over time for decision making to protect public health and maintain sustainable development of the catchment. 展开更多
关键词 DRINKING Water Nitrogen Phosphorus 3D spatio-temporal GEOSTATISTICS
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Study of the Spatio-Temporal Variability of Rainfall in the Northern Region of Senegal
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作者 Aichétou Dia Diop Abdoul Karim Mbodji +8 位作者 El Hadji Deme Malick Wade Mahamat Adoum Moussa Abdoulaye Bouya Diop Younousse Biaye Djiby Sarr Abdou Karim Farota Aboubakary Diakhaby Bouya Diop 《Journal of Geoscience and Environment Protection》 2023年第4期1-14,共14页
Senegal is a country of the Sahel. In this region, most of the populations live from agro-pastoral activities. The northern zone of Senegal is strongly influenced by river cultures. And the dynamics of the Senegal Riv... Senegal is a country of the Sahel. In this region, most of the populations live from agro-pastoral activities. The northern zone of Senegal is strongly influenced by river cultures. And the dynamics of the Senegal River are dependent on rainfall. The rainfall in the area is very closely linked to the dynamics of the atmosphere. The study of the spatio-temporal variability of rainfall in the northern region of Senegal requires quality rainfall observation data. It includes the Ferlo and the Senegal River valley, in particular the regions of Louga (department of Linguère included), Saint-Louis (departments of Dagana and Podor included) and Matam. These stations have been defined since Le Borgne (1988). The difficulty of having quality rain observation data can be resolved by using more accessible and good quality satellite data. Using satellite data, namely MSWEP, CRU, TAMSAT, ARC and PERSIANN, we showed the return of precipitation that appeared in 2000 and the unimodal cycle of precipitation in our study area. These data were validated using the correlation coefficient, the bias, the RMSE and the Nash index with observation data from the Regional Study Center for the Improvement of Adaptation to Drought (CERASS). The CRU data is then retained. Thus, this study made it possible to show the zonal distribution of rainfall in the northern zone of Senegal. 展开更多
关键词 Rainfall in the Northern Region of Senegal variability of Rainfall Satellite Data The Zonal Distribution of Rainfall
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Identifying the spatio-temporal variability of human activity intensity and associated drivers: a case study on the Tibetan Plateau
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作者 Cai LIU Haiyan ZHANG +4 位作者 Fuping GAN Yunge LU Hao WANG Jiahong ZHANG Xing JU 《Frontiers of Earth Science》 SCIE CSCD 2022年第3期744-756,共13页
Human activities have significantly degraded ecosystems and their associated services.By understanding the spatio-temporal variability and drivers of human activity intensity(HAI),we can better evaluate the interactio... Human activities have significantly degraded ecosystems and their associated services.By understanding the spatio-temporal variability and drivers of human activity intensity(HAI),we can better evaluate the interactions between human and terrestrial ecosystems,which is essential for land-use related decision making and eco-environmental construction.As the“third pole,”the Tibetan Plateau(TP)plays a strong role in shaping the global environment,and acts as an important ecological security barrier for China.Based on land-use/cover change data,environmental geographic data,and socioeconomic data,we adopted a method for converting different land use/cover types into construction land equivalent to calculate the HAI value and applied the Getis-Ord Gi*statistic to analyze the spatio-temporal dynamics associated with HAI since 1980 on the TP.Thereafter,we explored the forces driving the HAI changes using GeoDetector software and a correlation analysis.The main conclusions are as follows:It was observed that HAI increased slowly from 3.52%to 3.65%during the 1980-2020 period,with notable increases in the western part of the Qaidam Basin and Hehuang Valley.Spatially,HAI was associated with a significant agglomeration effect,which was mainly concentrated in the regions of the Yarlung Zangbo and Yellow-Huangshui rivers.Both natural and anthropogenic factors were identified as important driving forces behind the spatial changes in HAI,of which soil type,gross domestic product,and population density had the greatest influence.Meanwhile,the temporal changes in HAI were largely driven by economic development.This information provides crucial guidance for territory development planning and ecological-protection policy decisions. 展开更多
关键词 Tibetan Plateau human activity intensity GeoDetector spatio-temporal variability driving factors
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Natural and human-induced decline and spatio-temporal differentiation of terrestrial water storage over the Lancang-Mekong River Basin 被引量:2
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作者 CHEN Junxu WANG Yuan +5 位作者 ZHAO Zhifang FAN Yunjiang LUO Xiaochuan YI Lu FENG Siqi YANG Liang Emlyn 《Journal of Geographical Sciences》 2025年第1期112-138,共27页
Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB),the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified.This work investigated LM... Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB),the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified.This work investigated LMRB's terrestrial water storage anomaly(TWSA)and its spatio-temporal dynamics during 2002–2020.Considering the effects of natural factors and human activities,the respective contributions of climate variability and human activities to terrestrial water storage change(TWSC)were separated.Results showed that:(1)LMRB's TWSA decreased by 0.3158 cm/a.(2)TWSA showed a gradual increase in distribution from southwest of MRB to middle LMRB and from northeast of LRB to middle LMRB.TWSA positively changed in Myanmar while slightly changed in Laos and China.It negatively changed in Vietnam,Thailand and Cambodia.(3)TWSA components decreased in a descending order of soil moisture,groundwater and precipitation.(4)Natural factors had a substantial and spatial differentiated influence on TWSA over the LMRB.(5)Climate variability contributed 79%of TWSC in the LMRB while human activities contributed 21%with an increasing impact after 2008.The TWSC of upstream basin countries was found to be controlled by climate variability while Vietnam and Cambodia's TWSC has been controlled by human activities since 2012. 展开更多
关键词 spatio-temporal variation contribution separation GRACE Empirical Orthogonal Function Lancang-Mekong River
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Spatio-temporal changes of NDVI and its relation with climatic variables in the source regions of the Yangtze and Yellow rivers 被引量:25
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作者 YANG Zhaoping GAO Jixi +4 位作者 ZHOU Caiping SHI Peili ZHAO Lin SHEN Wenshou OUYANG Hua 《Journal of Geographical Sciences》 SCIE CSCD 2011年第6期979-993,共15页
The source regions of the Yangtze and Yellow rivers are important water conservation areas of China. In recent years, ecological deterioration trend of the source regions caused by global climate change and unreasonab... The source regions of the Yangtze and Yellow rivers are important water conservation areas of China. In recent years, ecological deterioration trend of the source regions caused by global climate change and unreasonable resource development increased gradually. In this paper, the spatial distribution and dynamic change of vegetation cover in the source regions of the Yangtze and Yellow rivers are analyzed in recent 10 years based on 1-km resolution multi-temporal SPOTVGT-DN data from 1998 to 2007. Meanwhile, the cor- relation relationships between air temperature, precipitation, shallow ground temperature and NDVI, which is 3x3 pixel at the center of Wudaoliang, Tuotuohe, Qumalai, Maduo, and Dari meteorological stations were analyzed. The results show that the NDVI values in these two source regions are increasing in recent 10 years. Spatial distribution of NDVI which was consistent with hydrothermal condition decreased from southeast to northwest of the source regions. NDVI with a value over 0.54 was mainly distributed in the southeastern source region of the Yellow River, and most NDVI values in the northwestern source region of the Yangtze River were less than 0.22. Spatial changing trend of NDVI has great difference and most parts in the source regions of the Yangtze and Yellow rivers witnessed indistinct change. The regions with marked increasing trend were mainly distributed on the south side of the Tongtian River, some part of Keqianqu, Tongtian, Chumaer, and Tuotuo rivers in the source region of the Yangtze River and Xingsuhai, and southern Dari county in the source region of the Yellow River. The regions with very marked increasing tendency were mainly distributed on the south side of Tongtian Rriver and sporadically distributed in hinterland of the source re- gion of the Yangtze River. The north side of Tangula Range in the source region of the Yangtze River and Dari and Maduo counties in the source region of the Yellow River were areas in which NDVI changed with marked decreasing tendency. The NDVI change was positively correlated with average temperature, precipitation and shallow ground temperature. Shallow ground temperature had the greatest effect on NDVI change, and the second greatest factor influencing NDVI was average temperature. The correlation between NDVI and shallow ground temperature in the source regions of the Yangtze and Yellow rivers increased significantly with the depth of soil layer. 展开更多
关键词 source regions of the Yangtze and Yellow rivers NDVI spatio-temporal change temperature PRECIPITATION shallow ground temperature
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Dynamic Multi-Graph Spatio-Temporal Graph Traffic Flow Prediction in Bangkok:An Application of a Continuous Convolutional Neural Network
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作者 Pongsakon Promsawat Weerapan Sae-dan +2 位作者 Marisa Kaewsuwan Weerawat Sudsutad Aphirak Aphithana 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期579-607,共29页
The ability to accurately predict urban traffic flows is crucial for optimising city operations.Consequently,various methods for forecasting urban traffic have been developed,focusing on analysing historical data to u... The ability to accurately predict urban traffic flows is crucial for optimising city operations.Consequently,various methods for forecasting urban traffic have been developed,focusing on analysing historical data to understand complex mobility patterns.Deep learning techniques,such as graph neural networks(GNNs),are popular for their ability to capture spatio-temporal dependencies.However,these models often become overly complex due to the large number of hyper-parameters involved.In this study,we introduce Dynamic Multi-Graph Spatial-Temporal Graph Neural Ordinary Differential Equation Networks(DMST-GNODE),a framework based on ordinary differential equations(ODEs)that autonomously discovers effective spatial-temporal graph neural network(STGNN)architectures for traffic prediction tasks.The comparative analysis of DMST-GNODE and baseline models indicates that DMST-GNODE model demonstrates superior performance across multiple datasets,consistently achieving the lowest Root Mean Square Error(RMSE)and Mean Absolute Error(MAE)values,alongside the highest accuracy.On the BKK(Bangkok)dataset,it outperformed other models with an RMSE of 3.3165 and an accuracy of 0.9367 for a 20-min interval,maintaining this trend across 40 and 60 min.Similarly,on the PeMS08 dataset,DMST-GNODE achieved the best performance with an RMSE of 19.4863 and an accuracy of 0.9377 at 20 min,demonstrating its effectiveness over longer periods.The Los_Loop dataset results further emphasise this model’s advantage,with an RMSE of 3.3422 and an accuracy of 0.7643 at 20 min,consistently maintaining superiority across all time intervals.These numerical highlights indicate that DMST-GNODE not only outperforms baseline models but also achieves higher accuracy and lower errors across different time intervals and datasets. 展开更多
关键词 Graph neural networks convolutional neural network deep learning dynamic multi-graph spatio-temporal
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Spatio-Temporal Pulsating Dissipative Solitons through Collective Variable Methods 被引量:2
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作者 Olivier Asseu Ambroise Diby +1 位作者 Pamela Yoboué Aladji Kamagaté 《Journal of Applied Mathematics and Physics》 2016年第6期1032-1041,共10页
A semi-analytical approach for the pulsating solutions of the 3D complex Cubic-quintic Ginzburg-Landau Equation (CGLE) is presented in this article. A collective variable approach is used to obtain a system of variati... A semi-analytical approach for the pulsating solutions of the 3D complex Cubic-quintic Ginzburg-Landau Equation (CGLE) is presented in this article. A collective variable approach is used to obtain a system of variational equations which give the evolution of the light pulses parameters as a function of the propagation distance. The collective coordinate approach is incomparably faster than the direct numerical simulation of the propagation equation. This allows us to obtain, efficiently, a global mapping of the 3D pulsating soliton. In addition it allows describing the influence of the parameters of the equation on the various physical parameters of the pulse and their dynamics. 展开更多
关键词 Dissipative Soliton Pulsating Light Pulse Spatiotemporal Pulses Collective Variable Approach Complex Cubic-Quintic Ginzburg-Landau Equation BIFURCATION
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Spatio-Temporal Pattern and Socio-economic Influencing Factors of Tuberculosis Incidence in Guangdong Province:A Bayesian Spatiotemporal Analysis
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作者 Huizhong Wu Xing Li +7 位作者 Jiawen Wang Ronghua Jian Jianxiong Hu Yijun Hu Yiting Xu Jianpeng Xiao Aiqiong Jin Liang Chen 《Biomedical and Environmental Sciences》 2025年第7期819-828,共10页
Objective To investigate the spatiotemporal patterns and socioeconomic factors influencing the incidence of tuberculosis(TB)in the Guangdong Province between 2010 and 2019.Method Spatial and temporal variations in TB ... Objective To investigate the spatiotemporal patterns and socioeconomic factors influencing the incidence of tuberculosis(TB)in the Guangdong Province between 2010 and 2019.Method Spatial and temporal variations in TB incidence were mapped using heat maps and hierarchical clustering.Socioenvironmental influencing factors were evaluated using a Bayesian spatiotemporal conditional autoregressive(ST-CAR)model.Results Annual incidence of TB in Guangdong decreased from 91.85/100,000 in 2010 to 53.06/100,000in 2019.Spatial hotspots were found in northeastern Guangdong,particularly in Heyuan,Shanwei,and Shantou,while Shenzhen,Dongguan,and Foshan had the lowest rates in the Pearl River Delta.The STCAR model showed that the TB risk was lower with higher per capita Gross Domestic Product(GDP)[Relative Risk(RR),0.91;95%Confidence Interval(CI):0.86–0.98],more the ratio of licensed physicians and physician(RR,0.94;95%CI:0.90-0.98),and higher per capita public expenditure(RR,0.94;95%CI:0.90–0.97),with a marginal effect of population density(RR,0.86;95%CI:0.86–1.00).Conclusion The incidence of TB in Guangdong varies spatially and temporally.Areas with poor economic conditions and insufficient healthcare resources are at an increased risk of TB infection.Strategies focusing on equitable health resource distribution and economic development are the key to TB control. 展开更多
关键词 TUBERCULOSIS BAYESIAN Social-economic factor spatio-temporal model
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Spatio-Temporal Assessment of Land Use Changes in Sonipat,Haryana:Socio Economic Impacts and Policy Intervention
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作者 Niraj Kumar Tejbir Singh Rana +1 位作者 Subhash Anand Nishit 《Research in Ecology》 2025年第3期309-334,共26页
This study examines the effects of rapid land use changes in India,with a specific focus on Sonipat District in Haryana—a region undergoing significant urban expansion.Over the past two decades,rural landscapes in So... This study examines the effects of rapid land use changes in India,with a specific focus on Sonipat District in Haryana—a region undergoing significant urban expansion.Over the past two decades,rural landscapes in Sonipat have undergone notable transformation,as open spaces and agricultural lands are increasingly converted into residential colonies,commercial hubs,and industrial zones.While such changes reflect economic development and urban growth,they also raise critical concerns about sustainability,especially in terms of food security,groundwater depletion,and environmental degradation.The study examines land use changes between 2000 and 2024 using remote sensing techniques and spatial analysis.It further incorporates secondary data and insights from community-level interactions to assess the socio-economic and ecological impacts of this transformation.The findings indicate rising land fragmentation,loss of agricultural livelihoods,pressure on civic infrastructure,and increasing pollution—factors that threaten long-term regional sustainability.The study underscores the urgent need to reconcile urban development with environmental and social sustainability.By offering a detailed case study of Sonipat,this research contributes to the broader discourse on India’s urbanisation pathways.It aims to provide policymakers,planners,and researchers with evidence-based recommendations to manage land transitions more responsibly,promoting urban growth models that ensure ecological integrity,equitable development,and long-term resilience. 展开更多
关键词 Land Use spatio-temporal Dynamics Socio-Economic Impacts URBANIZATION POLICY
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Deepfake Detection Method Based on Spatio-Temporal Information Fusion
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作者 Xinyi Wang Wanru Song +1 位作者 Chuanyan Hao Feng Liu 《Computers, Materials & Continua》 2025年第5期3351-3368,共18页
As Deepfake technology continues to evolve,the distinction between real and fake content becomes increasingly blurred.Most existing Deepfake video detectionmethods rely on single-frame facial image features,which limi... As Deepfake technology continues to evolve,the distinction between real and fake content becomes increasingly blurred.Most existing Deepfake video detectionmethods rely on single-frame facial image features,which limits their ability to capture temporal differences between frames.Current methods also exhibit limited generalization capabilities,struggling to detect content generated by unknown forgery algorithms.Moreover,the diversity and complexity of forgery techniques introduced by Artificial Intelligence Generated Content(AIGC)present significant challenges for traditional detection frameworks,whichmust balance high detection accuracy with robust performance.To address these challenges,we propose a novel Deepfake detection framework that combines a two-stream convolutional network with a Vision Transformer(ViT)module to enhance spatio-temporal feature representation.The ViT model extracts spatial features from the forged video,while the 3D convolutional network captures temporal features.The 3D convolution enables cross-frame feature extraction,allowing the model to detect subtle facial changes between frames.The confidence scores from both the ViT and 3D convolution submodels are fused at the decision layer,enabling themodel to effectively handle unknown forgery techniques.Focusing on Deepfake videos and GAN-generated images,the proposed approach is evaluated on two widely used public face forgery datasets.Compared to existing state-of-theartmethods,it achieves higher detection accuracy and better generalization performance,offering a robust solution for deepfake detection in real-world scenarios. 展开更多
关键词 Deepfake detection vision transformer spatio-temporal information
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Spatio-temporal pattern and influencing factors of sloping farmland in China
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作者 YAO Xiaowei XIE Youping +3 位作者 ZHUGE Jing ZENG Haibo ZENG Jie CHEN Wanxu 《Journal of Mountain Science》 2025年第11期4242-4257,共16页
Sloping farmland,particularly in mountainous and hilly areas,constitutes a significant component of regional farmland resources.An investigation into the spatio-temporal pattern of sloping farmland and its influencing... Sloping farmland,particularly in mountainous and hilly areas,constitutes a significant component of regional farmland resources.An investigation into the spatio-temporal pattern of sloping farmland and its influencing factors in China is imperative for the efficient utilization of farmland and the optimization of land space.We used land use transfer matrix,geographically weighted regression model and geographical detector to conduct this study.Results showed that sloping farmland in China firstly decreased and then increased from 2000 to 2020.The proportion of sloping farmland decreased radially outward from Sichuan basin to the surrounding areas.Change rates of sloping farmland with different slopes varied and the slope with 6°-15°underwent the fastest changes.The influencing factors of farmland at various slope degrees were different.For sloping farmland below 15°,land use intensity and elevation had the greatest contribution.For sloping farmland between 15°and 25°,elevation,land use intensity,and population density were the main influencing factors.Sloping farmland above 25°was mostly affected by natural factors.This study can provide scientific basis for rational development and protection of sloping farmland. 展开更多
关键词 Sloping farmland spatio-temporal differentiation Influencing factors Geographically weighted regression China
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Spatio-temporal dynamics and influencing factors of carbon emission intensity in China's agriculture sector
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作者 YIN Junfeng YE Sijing +1 位作者 SONG Changqing GAO Peichao 《Journal of Geographical Sciences》 2025年第11期2310-2334,共25页
Agriculture holds a pivotal position in the economic fabric of every nation,yet concerns about agricultural carbon emission intensity(ACI)have become a major hurdle to achieving global economic sustainability.Focusing... Agriculture holds a pivotal position in the economic fabric of every nation,yet concerns about agricultural carbon emission intensity(ACI)have become a major hurdle to achieving global economic sustainability.Focusing on 31 provincial-level regions in China,this study uses the Exploratory Spatio-temporal Data Analysis(ESTDA)and Panel Quantile Regression(PQR)model to analyze the spatio-temporal interaction characteristics and influencing factors of ACI in China from 2004 to 2023.The findings are as follows:(1)ACI showed an overall downward trend,and the spatial distribution pattern was characterized by“high in the western region and low along the southeastern coast”.Although the overall disparity tended to converge,some high-carbon-intensity regions exhibited extreme trends.ACI displayed clear spatial directionality,with the spatial center shifting steadily toward the northeast.(2)Regions in the northwest,northeast,and central-south parts exhibited strong local spatial structural dynamics,and the local spatial dependence of ACI in each region showed a nonlinear trend.Generally speaking,the spatial association pattern demonstrated a certain degree of inertia in spatial transfer,reflecting strong path dependence or spatial lock-in characteristics.(3)Optimization of industrial structure and improvement in agricultural mechanization will increase ACI,while economic development can effectively reduce it.The impact of urbanization on ACI exhibits a nonlinear pattern.The coordinated development of economic growth and urbanization significantly reduces ACI,with a stronger emission reduction observed in regions with low ACI.The optimization of industrial structure,when combined with urbanization and environmental regulation,contributes to significant emission reductions particularly in high-ACI areas.Similarly,the synergy between agricultural mechanization and urbanization effectively lowers emissions in low-ACI regions,though this effect diminishes in areas with higher ACI. 展开更多
关键词 agriculture sector carbon emission intensity spatio-temporal interaction influencing factors China
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Remote Sensing Derived Phenological Metrics to Assess the Spatio-Temporal Growth Variability in Cropping Fields
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作者 Sofanit Araya Bertram Ostendorf +1 位作者 Greg Lyle Megan Lewis 《Advances in Remote Sensing》 2017年第3期212-228,共17页
Precision Agriculture (PA) recognizes and manages intra-field spatial variability to increase profitability and reduced environmental impact. Site Specific Crop Management (SSCM), a form of PA, subdivides a cropping f... Precision Agriculture (PA) recognizes and manages intra-field spatial variability to increase profitability and reduced environmental impact. Site Specific Crop Management (SSCM), a form of PA, subdivides a cropping field into uniformly manageable zones, based on quantitative measurement of yield limiting factors. In Mediterranean environments, the spatial and temporal yield variability of rain-fed cropping system is strongly influenced by the spatial variability of Plant Available Water-holding Capacity (PAWC) and its strong interaction with temporally variable seasonal rainfall. The successful adoption of SSCM depends on the understanding of both spatial and temporal variabilities in cropping fields. Remote sensing phenological metrics provide information about the biophysical growth conditions of crops across fields. In this paper, we examine the potential of phenological metrics to assess the spatial and temporal crop yield variability across a wheat cropping field at Minnipa, South Australia. The Minnipa field was classified into three management zones using prolonged observations including soil assessment and multiple year yield data. The main analytical steps followed in this study were: calculation of the phenological metrics using time series NDVI data from Moderate Resolution Imaging Spectroscope (MODIS) for 15 years (2001-2015);producing spatial trend and temporal variability maps of phenological metrics;and finally, assessment of association between the spatial patterns and temporal variability of the metrics with management zones of the cropping field. The spatial trend of the seasonal peak NDVI metric showed significant association with the management zone pattern. In terms of temporal variability, Time-integrated NDVI (TINDVI) showed higher variability in the “good” zone compared with the “poor” zone. This indicates that the magnitude of the seasonal peak is more sensitive to soil related factors across the field, whereas TINDVI is more sensitive to seasonal variability. The interpretation of the association between phenological metrics and the management zone site conditions was discussed in relation to soil-climate interaction. The results demonstrate the potential of the phenological metrics to assess the spatial and temporal variability across cropping fields and to understand the soil-climate interaction. The approach presented in this paper provides a pathway to utilize phenological metrics for precision agricultural management application. 展开更多
关键词 Remote Sensing CROP PHENOLOGY MULTI-TEMPORAL Images NDVI Precision Agriculture spatio-temporal variability
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Reveal Immunological Changes and Coping Strategies of Sandfly Fever Based on Spatio-temporal Omics
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作者 Dong Liu Junjie Liu +2 位作者 Hongzhi Ding Yifan Long Guangxue Guo 《Asia Pacific Journal of Clinical Medical Research》 2025年第4期11-18,共8页
Sandfly fever is a viral infectious disease transmitted by sand flies that is widely prevalent in tropical and subtropical regions.Previous studies on its infection mechanism,immune response and diagnosis and treatmen... Sandfly fever is a viral infectious disease transmitted by sand flies that is widely prevalent in tropical and subtropical regions.Previous studies on its infection mechanism,immune response and diagnosis and treatment methods were lack of systematic.This study applied spatio-temporal omics technology to comprehensively explain the dynamic changes of immunity in the incubation period,exacerbation period,peak period and recovery period of Sandfl y fever,and integrated with diff erent coping strategies.To provide new research ideas for its overall research. 展开更多
关键词 spatio-temporal Omics Sandfl y Fever Immunity Coping Strategies Virus Infection
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An Arrhythmia Intelligent Recognition Method Based on a Multimodal Information and Spatio-Temporal Hybrid Neural Network Model
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作者 Xinchao Han Aojun Zhang +6 位作者 Runchuan Li Shengya Shen Di Zhang Bo Jin Longfei Mao Linqi Yang Shuqin Zhang 《Computers, Materials & Continua》 2025年第2期3443-3465,共23页
Electrocardiogram (ECG) analysis is critical for detecting arrhythmias, but traditional methods struggle with large-scale Electrocardiogram data and rare arrhythmia events in imbalanced datasets. These methods fail to... Electrocardiogram (ECG) analysis is critical for detecting arrhythmias, but traditional methods struggle with large-scale Electrocardiogram data and rare arrhythmia events in imbalanced datasets. These methods fail to perform multi-perspective learning of temporal signals and Electrocardiogram images, nor can they fully extract the latent information within the data, falling short of the accuracy required by clinicians. Therefore, this paper proposes an innovative hybrid multimodal spatiotemporal neural network to address these challenges. The model employs a multimodal data augmentation framework integrating visual and signal-based features to enhance the classification performance of rare arrhythmias in imbalanced datasets. Additionally, the spatiotemporal fusion module incorporates a spatiotemporal graph convolutional network to jointly model temporal and spatial features, uncovering complex dependencies within the Electrocardiogram data and improving the model’s ability to represent complex patterns. In experiments conducted on the MIT-BIH arrhythmia dataset, the model achieved 99.95% accuracy, 99.80% recall, and a 99.78% F1 score. The model was further validated for generalization using the clinical INCART arrhythmia dataset, and the results demonstrated its effectiveness in terms of both generalization and robustness. 展开更多
关键词 Multimodal learning spatio-temporal hybrid graph convolutional network data imbalance ECG classification
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