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Spatiotemporal patterns and driving forces of dust weather events in Central Asia from 2000 to 2020
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作者 LIU Yuhan ZHAO Yuanyuan +2 位作者 GAO Guanglei DING Guodong LI Ning 《Journal of Arid Land》 2026年第1期1-16,共16页
Central Asia is characterized by an arid climate and widespread desert distribution,with its sustainable development severely constrained by dust events.An objective understanding of the spatiotemporal patterns and dr... Central Asia is characterized by an arid climate and widespread desert distribution,with its sustainable development severely constrained by dust events.An objective understanding of the spatiotemporal patterns and driving forces of dust weather is highly important in this area.Based on the meteorological observations from 2000 to 2020,we examined the spatiotemporal characteristics of dust weather in the five Central Asian countries(Kazakhstan,Uzbekistan,Kyrgyzstan,Turkmenistan,and Tajikistan)via Theil-Sen trend analysis and Geodetector modeling method,quantitatively revealing the influence of environmental factors,such as temperature,precipitation,and vegetation,on the frequency of dust weather.The results showed that:(1)dust weather in Central Asia was mainly distributed in a large''dust belt''extending from west to east from northern part of the Caspian lowland desert,and concentrated in basins,plains,and other low-altitude areas.Strong dust weather mainly occurred in northern areas of the Aral Sea and southern edge of Central Asia,with a maximum annual frequency of 21.9%;(2)strong dust weather in Central Asia has fluctuated and slightly decreased since 2001.The highest frequency(1.1%)occurred in spring(from March to June);(3)from 2000 to 2020,changes such as spot shifting and shrinking occurred in the four main source areas(north of the Aral Sea,Kyzylkum Desert,Karakum Desert,and Garabogazköl Bay region),where sandstorms occurred in Central Asia,and northern Caspian lowland desert became the most important low-emission dust source in Central Asia;and(4)the combined effect of soil moisture and air temperature has the most significant influence on dust weather in Central Asia.This study provides a theoretical basis for sand prevention and sand control in Central Asia.In the future,Central Asia should focus on the rational utilization of land and water resources,and implement human interventions such as vegetation restoration and optimization of irrigation methods to curb further desertification in this area. 展开更多
关键词 Central Asia dust weather temporal and spatial distribution influencing factor Geodetector
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The Interaction Mechanism Between Urban Scale Hierarchy and Urban Networks in China:An Analysis Based on A Spatial Simultaneous Equation Model
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作者 ZHOU Ying ZHENG Wensheng WANG Xiaofang 《Chinese Geographical Science》 2026年第1期19-33,共15页
Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefor... Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefore,this paper analyzes the spatial interaction between urban scale hierarchy and urban networks in China from 2019 to 2023,drawing on Baidu migration data and employing a spatial simultaneous equation model.The results reveal a significant positive spatial correlation between cities with higher hierarchy and those with greater network centrality.Within a static framework,we identify a positive interaction between urban scale hierarchy and urban network centrality,while their spatial cross-effects manifest as negative neighborhood interactions based on geographical distance and positive cross-scale interactions shaped by network connections.Within a dynamic framework,changes in urban scale hierarchy and urban networks are mutually reinforcing,thereby widening disparities within the urban hierarchy.Furthermore,an increase in a city’s network centrality had a dampening effect on the population growth of neighboring cities and network-connected cities.This study enhances understanding of the spatial organisation of urban systems and offers insights for coordinated regional development. 展开更多
关键词 urban scale hierarchy urban networks spatial interaction spatial spillover effect Baidu migration data spatial simultaneous equation model China
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Spatio-temporal responses of ecological resilience to urbanization in five Great Lakes Regions(GLRs)in China and implications for building resilient GLRs
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作者 Tongning Li Guoen Wei +4 位作者 Minghui Xu Daozheng Li Weifeng Deng Yaobin Liu Bao-Jie He 《Geography and Sustainability》 2026年第1期218-231,共14页
Great Lakes Regions(GLRs)in China often confront landscape fragmentation,wetland degradation,and ecological resilience(ER)losses owing to extensive and intensive urbanization.In GLRs,however,the ER responses to urbani... Great Lakes Regions(GLRs)in China often confront landscape fragmentation,wetland degradation,and ecological resilience(ER)losses owing to extensive and intensive urbanization.In GLRs,however,the ER responses to urbanization remain unclear.This study explored the spatiotemporal evolution of ER and urbanization in five GLRs in China to analyze the ER dynamic patterns along center−lakeside−periphery gradient.The Spatial Durbin Model(SDM)and Panel Threshold Model(PTM)were combined to reveal the spillover and threshold effects of urbanization in five GLRs.The results indicate that the ER in five GLRs declined with a rate of 21%from 2000 to 2020.There was a clear“center-periphery”contraction trend with low ER areas primarily spreading to human activity-concentrated regions such as lakesides,riversides,and road networks.Driven by economic and land urbanization,the average urbanization level increased from 0.06 to 0.13,where lakesides,riversides,and road networks were key areas undergoing expansion.The urbanization showed a noticeable negative spatial spillover effect on ER.Away from central lakes,the negative impacts on ER exhibited a two-phase decrease with the threshold of 81 km.This study contributes to the understanding of human-environment interactions by examining the ecological resilience response process of GLRs under the impact of urbanization.Based on a multidimensional“center−lakeside−periphery”analytical model,this study provides a strategic framework for ecological construction in GLRs in China,promoting sustainable development and adaptive capacity in vulnerable areas. 展开更多
关键词 Ecological resilience URBANIZATION spatial durbin model Panel threshold model Great Lakes Region
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Spatial response and prediction model for blasting-induced vibration in a deep double-line tunnel
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作者 Chong Yu Yongan Ma +3 位作者 Haibo Li Changjian Wang Haibin Wang Linghao Meng 《International Journal of Mining Science and Technology》 2026年第1期169-186,共18页
Excessive blasting-induced vibration during drilling-and-blasting excavation of deep tunnels can trigger geological hazards and compromise the stability of both the rock mass and support structures.This study focused ... Excessive blasting-induced vibration during drilling-and-blasting excavation of deep tunnels can trigger geological hazards and compromise the stability of both the rock mass and support structures.This study focused on the deep double-line Sejila Mountain tunnel to systematically analyze the spatial response of blasting-induced vibration and to develop a prediction model through field tests and numerical simulations.The results revealed that the presence of a cross passage significantly altered propagation paths and the spatial distribution of blasting-induced vibration velocity.The peak particle velocity(PPV)at the cross-passage corner was amplified by approximately 1.92 times due to wave reflection and geometric focusing.Blasting-induced vibration waves attenuated non-uniformly across the tunnel cross-section,where PPV on the blast-face side was 1.54–6.56 times higher than that on the opposite side.We propose an improved PPV attenuation model that accounts for the propagation path effect.This model significantly improved fitting accuracy and resolved anomalous parameter(k and a)estimates in traditional equations,thereby improving prediction reliability.Furthermore,based on the observed spatial distribution of blasting-induced vibration,optimal monitoring point placement and targeted vibration control measures for tunnel blasting were discussed.These findings provide a scientific basis for designing blasting schemes and vibration mitigation strategies in deep tunnels. 展开更多
关键词 Blasting-induced vibration spatial response Attenuation law Prediction model Double-line tunnel
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Spatio-temporal changes in forest tree species diversity in China over the past 20 years
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作者 Yonghong Zhang Liang Shi +7 位作者 Honglin He Qingqing Chang Jianming Deng Yan Lv Qian Xu Weihua Liu Mengyu Zhang Chenxi Li 《Journal of Forestry Research》 2026年第1期230-241,共12页
The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about ... The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about whether the LDG remains stable over time as climate warming progresses and whether MTE remains applicable to clarify this pattern.In this study,forest data spanning temperate,subtropical,and tropical zones across China were used to analyze long-term changes in the LDG of tree species over 2005-2020.Based on the MTE framework,spatial scales were considered to assess temperature dependence of typical forest trees species.Our results show that species richness decreased with increasing latitude,and that temperature was the primary driver of this change.Although temperature in China has significantly increased over the past two decades,the LDG of tree species has remained stable.However,there was a decrease in species richness in tropical regions over time.With predictions of the MTE,the logarithm of typical forest tree species richness exhibited negative linear relationships with the inverse of ambient temperature,indicating temperature dependence of species richness.However,the relationship remained stable and was strongly influenced by spatial scale,intensifying as spatial scale increased.The findings emphasize the important role of temperature in shaping the LDG.The effects of spatial scale,in particular,should be considered when biodiversity management plans are developed for future climate change. 展开更多
关键词 Climate warming Latitudinal diversity gradient(LDG) Metabolic theory of ecology Species richness spatial scale temporal dynamic
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Learning Time Embedding for Temporal Knowledge Graph Completion
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作者 Jinglu Chen Mengpan Chen +2 位作者 Wenhao Zhang Huihui Ren Daniel Dajun Zeng 《Computers, Materials & Continua》 2026年第2期827-851,共25页
Temporal knowledge graph completion(TKGC),which merges temporal information into traditional static knowledge graph completion(SKGC),has garnered increasing attention recently.Among numerous emerging approaches,transl... Temporal knowledge graph completion(TKGC),which merges temporal information into traditional static knowledge graph completion(SKGC),has garnered increasing attention recently.Among numerous emerging approaches,translation-based embedding models constitute a prominent approach in TKGC research.However,existing translation-based methods typically incorporate timestamps into entities or relations,rather than utilizing them independently.This practice fails to fully exploit the rich semantics inherent in temporal information,thereby weakening the expressive capability of models.To address this limitation,we propose embedding timestamps,like entities and relations,in one or more dedicated semantic spaces.After projecting all embeddings into a shared space,we use the relation-timestamp pair instead of the conventional relation embedding as the translation vector between head and tail entities.Our method elevates timestamps to the same representational significance as entities and relations.Based on this strategy,we introduce two novel translation-based embedding models:TE-TransR and TE-TransT.With the independent representation of timestamps,our method not only enhances capabilities in link prediction but also facilitates a relatively underexplored task,namely time prediction.To further bolster the precision and reliability of time prediction,we introduce a granular,time unit-based timestamp setting and a relation-specific evaluation protocol.Extensive experiments demonstrate that our models achieve strong performance on link prediction benchmarks,with TE-TransR outperforming existing baselines in the time prediction task. 展开更多
关键词 temporal knowledge graph(TKG) TKG embedding model link prediction time prediction
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Probabilistic seismic hazard analysis for the northern segment of the North-South Seismic Belt in China based on improved spatial smoothing and fault source model integration
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作者 Yaohu Zhang Hua Pan +1 位作者 Meng Zhang Ying Shi 《Earthquake Science》 2026年第1期1-31,共31页
The northern segment of the North-South Seismic Belt is characterized by intense crustal deformation,well-developed active tectonics,and frequent occurrences of strong earthquakes.Therefore,conducting a Probabilistic ... The northern segment of the North-South Seismic Belt is characterized by intense crustal deformation,well-developed active tectonics,and frequent occurrences of strong earthquakes.Therefore,conducting a Probabilistic Seismic Hazard Analysis(PSHA)for this region is of significant importance for supporting seismic fortification in major engineering projects and formulating disaster prevention and mitigation policies.In this study,a composite seismic source model was constructed by integrating data on historical earthquakes,active faults,and paleoseismicity.Furthermore,a logic tree framework was employed to quantify epistemic uncertainties,enabling a systematic seismic hazard assessment of the region.To more accurately characterize the spatial heterogeneity of seismic activity,improvements were made to both the Circular Spatial Smoothing Model(CSSM)with a fixed radius and the Adaptive Spatial Smoothing Model(ASSM),with full consideration given to the spatiotemporal completeness of historical earthquake magnitudes.Regarding the CSSM,for scenarios involving small sample sizes in earthquake catalogs,the cross-validation method proposed in this study demonstrated higher robustness than the maximum likelihood method in determining the optimal correlation distance.Performance evaluation results indicate that while both models effectively characterize seismic activity,the ASSM exhibits superior overall predictive performance compared to the CSSM,owing to its ability to adaptively adjust the smoothing radius according to seismic density.Significant discrepancies were observed in the Peak Ground Acceleration(PGA)results calculated with a 10%probability of exceedance in 50 years across different combinations of seismic source models.The single spatially smoothed point-source model yielded a maximum PGA of approximately 0.52 g,with high-value areas concentrated near historical epicenters,thereby significantly underestimating the hazard associated with major fault zones.When combined with the simple fault-source model,the maximum PGA increased to 0.8 g,with high-value zones exhibiting a zonal distribution along faults;however,the risk remained underestimated for faults with low slip rates that are nevertheless approaching their recurrence cycles.Following the introduction of the time-dependent characteristic fault-source model,local PGA values for faults in the middle-to-late stages of their recurrence cycles increased by a factor of 2 to 7 compared to the single model.These results demonstrate that the characteristic fault-source model reasonably delineates the time-dependence of large earthquake recurrence,thereby providing a more accurate assessment of imminent seismic risks.By comprehensively applying the improved spatially smoothed pointsource model,the simple fault-source model,and the characteristic fault-source model,the following faults within the region were identified as having high seismic hazard:the Huangxianggou,Zhangxian,and Tianshui segments of the Xiqinling northern edge fault;the Maqin-Maqu segment of the Dongkunlun fault;the Longriqu fault;the Maoergai fault;the Elashan fault;the Riyueshan fault;the eastern segment of the Lenglongling fault;the Maxianshan segment of the Maxianshan northern Margin fault;and the Maomaoshan-Jinqianghe segment of the Laohushan-Maomaoshan fault.As these faults are located within seismic gaps or are approaching the recurrence periods of large earthquakes,they should be prioritized for current and future seismic monitoring as well as disaster prevention and mitigation efforts. 展开更多
关键词 northern segment of the North-South Seismic Belt fault-source characteristic earthquake spatial smoothing model
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Spatial and Temporal Evolution of Lithospheric Mantle beneath the Eastern North China Craton:Constraints from Mineral Chemistry of Peridotite Xenoliths from the Miocene Qingyuan Basalts and a Regional Synthesis 被引量:1
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作者 Jian-Fang Guo Qiang Ma +1 位作者 Jian-Ping Zheng Yu-Ping Su 《Journal of Earth Science》 2025年第2期474-484,共11页
Mineralogical data are presented for the peridotite xenoliths from Miocene(~19 Ma)Qingyuan basalts in the eastern North China Craton(NCC),with the aim of constraining on property of the sub-continental lithospheric ma... Mineralogical data are presented for the peridotite xenoliths from Miocene(~19 Ma)Qingyuan basalts in the eastern North China Craton(NCC),with the aim of constraining on property of the sub-continental lithospheric mantle(SCLM)beneath the northern Tan-Lu fault zone(TLFZ)during the Cenozoic.The Qingyuan peridotites are dominated by spinel lherzolites with moderate-Mg^(#)olivines(89.4 to 91.2),suggesting that the regional SCLM is mainly transitional and fertile.Light rare earth element(LREE)-depleted,slightly depleted and enriched clinopyroxenes(Cpx)are identified in different peridotites.Chemical compositions of the LREE-enriched Cpx and the presence of phlogopite suggest that the Qingyuan SCLM has experienced silicate-related metasomatism.The synthesis of available mineral chemical data of the mantle xenoliths across the NCC confirms the SCLM beneath the NCC is highly heterogeneous in time and space.The Mesozoic–Cenozoic SCLM beneath the TLFZ and neighboring regions are more fertile and thinner than that beneath the region away from the fault zone.The fertile and refractory peridotite xenoliths experienced varying degrees of silicate and carbonatite metasomatism,respectively.The spatial-temporal lithospheric mantle heterogeneity in composition,age and thickness suggest that the trans-lithosphere fault zone played an important role in heterogeneous replacement of refractory cratonic lithospheric mantle. 展开更多
关键词 lithospheric mantle peridotite xenoliths temporal and spatial variations Tan-Lu fault zone North China craton PETROLOGY GEOCHEMISTRY
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Robust human motion prediction via integration of spatial and temporal cues
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作者 ZHANG Shaobo LIU Sheng +1 位作者 GAO Fei FENG Yuan 《Optoelectronics Letters》 2025年第8期499-506,共8页
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
关键词 human p integration spatial temporal cues ristc human motion prediction temporal cues mixed feature extractor spatial cues artificial intelligence spatio temporal correlation
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Temporal and spatial distribution characteristics of water resources in Guangdong Province based on a cloud model 被引量:9
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作者 Qi Zhou Wei Wang +2 位作者 Yong Pang Zhi-yong Zhou Hui-ping Luo 《Water Science and Engineering》 EI CAS CSCD 2015年第4期263-272,共10页
With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distr... With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distribution characteristics of water resources in Guangdong Province from 1956 to 2000 based on a cloud model. The spatial variation of the temporal distribution characteristics and the temporal variation of the spatial distribution characteristics were both analyzed. In addition, the relationships between the numerical characteristics of the cloud model of temporal and spatial distributions of water resources and precipitation were also studied. The results show that, using a cloud model, it is possible to intuitively describe the temporal and spatial distribution characteristics of water resources in cloud images. Water resources in Guangdong Province and their temporal and spatial distribution characteristics are differentiated by their geographic locations. Downstream and coastal areas have a larger amount of water resources with greater uniformity and stronger stability in terms of temporal distribution. Regions with more precipitation possess larger amounts of water resources, and years with more precipitation show greater nonuniformity in the spatial distribution of water resources. The correlation between the nonuniformity of the temporal distribution and local precipitation is small, and no correlation is found between the stability of the nonuniformity of the temporal and spatial distributions of water resources and precipitation. The amount of water resources in Guangdong Province shows an increasing trend from 1956 to 2000, the nonuniformity of the spatial distribution of water resources declines, and the stability of the nonuniformity of the spatial distribution of water resources is enhanced. 展开更多
关键词 Water resources temporal and spatial distribution characteristics Cloud model Guangdong Province
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Spatio-temporal dynamics of maize cropping system in Northeast China between 1980 and 2010 by using spatial production allocation model 被引量:12
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作者 TAN Jieyang YANG Peng +6 位作者 LIU Zhenhuan WU Wenbin ZHANG Li LI Zhipeng YOU Liangzhi TANG Huajun LI Zhengguo 《Journal of Geographical Sciences》 SCIE CSCD 2014年第3期397-410,共14页
Understanding crop patterns and their changes on regional scale is a critical re- quirement for projecting agro-ecosystem dynamics. However, tools and methods for mapping the distribution of crop area and yield are st... Understanding crop patterns and their changes on regional scale is a critical re- quirement for projecting agro-ecosystem dynamics. However, tools and methods for mapping the distribution of crop area and yield are still lacking. Based on the cross-entropy theory, a spatial production allocation model (SPAM) has been developed for presenting spa- tio-temporal dynamics of maize cropping system in Northeast China during 1980-2010. The simulated results indicated that (1) maize sown area expanded northwards to 48~N before 2000, after that the increased sown area mainly occurred in the central and southern parts of Northeast China. Meanwhile, maize also expanded eastwards to 127°E and lower elevation (less than 100 m) as well as higher elevation (mainly distributed between 200 m and 350 m); (2) maize yield has been greatly promoted for most planted area of Northeast China, espe- cially in the planted zone between 42°N and 48°N, while the yield increase was relatively homogeneous without obvious longitudinal variations for whole region; (3) maize planting density increased gradually to a moderately high level over the investigated period, which reflected the trend of aggregation of maize cultivation driven by market demand. 展开更多
关键词 spring maize spatial production allocation model spatio-temporal pattern Northeast China
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Spatial-temporal Dynamics of Tuberculosis and Its Association with Meteorological Factors and Air Pollution in Shaanxi Province,China
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作者 Hengliang Lyu Xihao Liu +6 位作者 Hui Chen Xueli Zhang Feng Liu Zitong Zheng Hongwei Zhang Yuanyong Xu Wenyi Zhang 《Biomedical and Environmental Sciences》 2025年第7期867-872,共6页
Tuberculosis(TB)remained the first leading cause of death from a single infectious agent worldwide in 2023,resulting in nearly twice as many deaths as those caused by the human immunodeficiency virus/acquired immune d... Tuberculosis(TB)remained the first leading cause of death from a single infectious agent worldwide in 2023,resulting in nearly twice as many deaths as those caused by the human immunodeficiency virus/acquired immune deficiency syndrome.An estimated 10.8 million TB cases were reported globally in 2023,with approximately 1.25 million associated deaths.In China,which ranks third in the global TB burden,there were approximately 741,000 new cases and 25,000 deaths in 2023^([1]).TB poses a significant threat to human health worldwide. 展开更多
关键词 air pollution TUBERCULOSIS Shaanxi province meteorological factors China spatial temporal dynamics
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Spatial and Temporal Distribution Characteristics of PM 10 Concentration in Yantai City and Its Relationship with Meteorological Factors
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作者 Yumeng JIANG 《Meteorological and Environmental Research》 2025年第3期22-26,32,共6页
Based on the monitoring data of PM 10 concentration from six environmental monitoring stations and the ground meteorological observation data in Yantai City from 2019 to 2021,the spatial and temporal variation of PM 1... Based on the monitoring data of PM 10 concentration from six environmental monitoring stations and the ground meteorological observation data in Yantai City from 2019 to 2021,the spatial and temporal variation of PM 10 concentration and its relationship with meteorological factors were studied.The results show that from the perspective of temporal variation,the annual average of PM 10 concentration in Yantai City tended to decrease year by year.It was high in winter and spring and low in summer and autumn.In terms of monthly variation,the changing curve is U-shaped,and it was high in December and January but low in July and August.During a day,PM 10 concentration had two peaks.The first peak appeared approximately from 09:00 to 11:00,and the second peak can be found from 21:00 to 23:00.From the perspective of spatial distribution,PM 10 concentration was the highest in the development area and Fushan District.It was the highest in the west,followed by the east,while it was the lowest in the middle.The spatial difference rate was the highest in summer.Average temperature,relative humidity,wind speed and precipitation were the main meteorological factors influencing PM 10 concentration in Yantai area.PM 10 concentration was negatively correlated with average temperature and relative humidity,and the correlation was the most significant from June to October.It was negatively correlated with wind speed and precipitation,and the correlation was different in various months.The negative correlation was significant in summer and winter. 展开更多
关键词 Yantai City PM 10 spatial and temporal distribution Meteorological factors CORRELATION
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Analysis of Temporal and Spatial Variation Characteristics of NDVI in Siziwang Banner and Its Correlation with Meteorological Factors
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作者 Xinyu CHEN 《Meteorological and Environmental Research》 2025年第6期83-85,92,共4页
Based on the data of NDVI and meteorological factors in Siziwang Banner from 2000 to 2021,the temporal and spatial variation characteristics of NDVI in the grassland of Siziwang Banner and its responses to climate cha... Based on the data of NDVI and meteorological factors in Siziwang Banner from 2000 to 2021,the temporal and spatial variation characteristics of NDVI in the grassland of Siziwang Banner and its responses to climate change were analyzed.The results show that the NDVI of grassland in Siziwang Banner tended to rise overall,with the average tendency rate of 0.05/10 a.The annual variation of NDVI was mainly driven by precipitation,and there was an extremely significant positive correlation between the two.During the growing season,temperature was positively correlated with NDVI in May,but then the correlation gradually turned negative.NDVI was generally positively correlated with precipitation,and there was a significant lag. 展开更多
关键词 NDVI Satellite remote sensing temporal and spatial changes Climate response
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Human Motion Prediction Based on Multi-Level Spatial and Temporal Cues Learning
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作者 Jiayi Geng Yuxuan Wu +5 位作者 Wenbo Lu Pengxiang Su Amel Ksibi Wei Li Zaffar Ahmed Shaikh Di Gai 《Computers, Materials & Continua》 2025年第11期3689-3707,共19页
Predicting human motion based on historical motion sequences is a fundamental problem in computer vision,which is at the core of many applications.Existing approaches primarily focus on encoding spatial dependencies a... Predicting human motion based on historical motion sequences is a fundamental problem in computer vision,which is at the core of many applications.Existing approaches primarily focus on encoding spatial dependencies among human joints while ignoring the temporal cues and the complex relationships across non-consecutive frames.These limitations hinder the model’s ability to generate accurate predictions over longer time horizons and in scenarios with complex motion patterns.To address the above problems,we proposed a novel multi-level spatial and temporal learning model,which consists of a Cross Spatial Dependencies Encoding Module(CSM)and a Dynamic Temporal Connection Encoding Module(DTM).Specifically,the CSM is designed to capture complementary local and global spatial dependent information at both the joint level and the joint pair level.We further present DTM to encode diverse temporal evolution contexts and compress motion features to a deep level,enabling the model to capture both short-term and long-term dependencies efficiently.Extensive experiments conducted on the Human 3.6M and CMU Mocap datasets demonstrate that our model achieves state-of-the-art performance in both short-term and long-term predictions,outperforming existing methods by up to 20.3% in accuracy.Furthermore,ablation studies confirm the significant contributions of the CSM and DTM in enhancing prediction accuracy. 展开更多
关键词 Human motion prediction spatial dependencies learning temporal context learning graph convolutional networks transformer
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SG-TE:Spatial Guidance and Temporal Enhancement Network for Facial-Bodily Emotion Recognition
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作者 Zhong Huang Danni Zhang +3 位作者 Fuji Ren Min Hu Juan Liu Haitao Yu 《CAAI Transactions on Intelligence Technology》 2025年第3期871-890,共20页
To overcome the deficiencies of single-modal emotion recognition based on facial expression or bodily posture in natural scenes,a spatial guidance and temporal enhancement(SG-TE)network is proposed for facial-bodily e... To overcome the deficiencies of single-modal emotion recognition based on facial expression or bodily posture in natural scenes,a spatial guidance and temporal enhancement(SG-TE)network is proposed for facial-bodily emotion recognition.First,ResNet50,DNN and spatial ransformer models are used to capture facial texture vectors,bodily skeleton vectors and wholebody geometric vectors,and an intraframe correlation attention guidance(S-CAG)mechanism,which guides the facial texture vector and the bodily skeleton vector by the whole-body geometric vector,is designed to exploit the spatial potential emotional correlation between face and posture.Second,an interframe significant segment enhancement(T-SSE)structure is embedded into a temporal transformer to enhance high emotional intensity frame information and avoid emotional asynchrony.Finally,an adaptive weight assignment(M-AWA)strategy is constructed to realise facial-bodily fusion.The experimental results on the BabyRobot Emotion Dataset(BRED)and Context-Aware Emotion Recognition(CAER)dataset indicate that the proposed network reaches accuracies of 81.61%and 89.39%,which are 9.61%and 9.46%higher than those of the baseline network,respectively.Compared with the state-of-the-art methods,the proposed method achieves 7.73%and 20.57%higher accuracy than single-modal methods based on facial expression or bodily posture,respectively,and 2.16%higher accuracy than the dual-modal methods based on facial-bodily fusion.Therefore,the proposed method,which adaptively fuses the complementary information of face and posture,improves the quality of emotion recognition in real-world scenarios. 展开更多
关键词 bodily posture facial expression intraframe spatial guidance interframe temporal enhancement multimodal feature fusion
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Temporal and Spatial Variations in the Concentration of Negative Ions and Its Influencing Factors in Xinfeng County
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作者 Yiping LIN Xuanying XIE +1 位作者 Liqing ZHOU Liwen YE 《Meteorological and Environmental Research》 2025年第1期41-43,48,共4页
Based on the data of meteorological elements and concentration of negative ions in the county town station,Luguhe station and Yunjishan station during 2020-2024,the temporal and spatial variations in the concentration... Based on the data of meteorological elements and concentration of negative ions in the county town station,Luguhe station and Yunjishan station during 2020-2024,the temporal and spatial variations in the concentration of negative ions and their influencing factors in Xinfeng County were analyzed.The results show that the concentration of negative ions was the highest in summer,followed by spring;it was lower in autumn and the lowest in winter.In terms of diurnal variations,it was higher in the early morning and night,and lower in the noon and afternoon,which was closely related to the diurnal variations of human activities and meteorological conditions.The factors that affect the concentration of negative ions in the air are more complex.Besides meteorological factors,vegetation,altitude,human activities and other factors should be considered. 展开更多
关键词 Concentration of negative ions temporal and spatial variations Influencing factors Xinfeng County
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Spatial and Temporal Changes and Influencing Factors of Ecosystem Service Value in Jingzhou City Based on Land Use Change
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作者 GAO Yanpeng WANG Wanxi 《Journal of Landscape Research》 2025年第1期35-42,共8页
This study investigated the spatio-temporal variation characteristics of ecosystem service value(ESV)alongside its driving influencing factors,thereby offering valuable theoretical insights for the sustainable develop... This study investigated the spatio-temporal variation characteristics of ecosystem service value(ESV)alongside its driving influencing factors,thereby offering valuable theoretical insights for the sustainable development of Jingzhou City,Hubei Province.Based on the land use data for Jingzhou City from 2000 to 2020,this study quantified the value of the ecological environment using the equivalent factor method.Furthermore,it analyzed and elucidated the spatio-temporal heterogeneity and driving mechanisms of ecosystem services in Jingzhou City.The results indicated that between 2000 and 2020,cultivated land(66.40%)and water area(18.82%)were the predominant land use types in Jingzhou City.The areas of water area and construction land exhibited a growth trend during this period.Construction land had the highest rate of land use change,followed by water area and cultivated land.Land use transitions primarily occurred between cultivated land and water area,as well as between cultivated land and construction land.The total value of ecosystem services in Jingzhou City increased by 165.07%from 2000 to 2020.ESV exhibited an upward trend from 2000 to 2015,followed by a gradual decline from 2015 to 2020.The ranking of individual ecosystem services,in descending order,was as follows:regulation services,supporting services,provisioning services,and cultural services.High-value ESV areas were predominantly situated in the water area of Lake Honghu,while low-value regions were mainly found in the cultivated land in the central and western parts of Jingzhou City.The spatial differentiation of ESV in Jingzhzou City was influenced by both natural and socio-economic factors,with natural factors exerting a more significant impact than socioeconomic factors.Specifically,the Normalized Difference Vegetation Index(NDVI)was the dominant environmental factor,while GDP plays a synergistic role. 展开更多
关键词 Land use change Ecosystem service value temporal and spatial variations Geographical detector Jingzhou City
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Learning Temporal User Features for Repost Prediction with Large Language Models
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作者 Wu-Jiu Sun Xiao Fan Liu 《Computers, Materials & Continua》 2025年第3期4117-4136,共20页
Predicting information dissemination on social media,specifcally users’reposting behavior,is crucial for applications such as advertising campaigns.Conventional methods use deep neural networks to make predictions ba... Predicting information dissemination on social media,specifcally users’reposting behavior,is crucial for applications such as advertising campaigns.Conventional methods use deep neural networks to make predictions based on features related to user topic interests and social preferences.However,these models frequently fail to account for the difculties arising from limited training data and model size,which restrict their capacity to learn and capture the intricate patterns within microblogging data.To overcome this limitation,we introduce a novel model Adapt pre-trained Large Language model for Reposting Prediction(ALL-RP),which incorporates two key steps:(1)extracting features from post content and social interactions using a large language model with extensive parameters and trained on a vast corpus,and(2)performing semantic and temporal adaptation to transfer the large language model’s knowledge of natural language,vision,and graph structures to reposting prediction tasks.Specifcally,the temporal adapter in the ALL-RP model captures multi-dimensional temporal information from evolving patterns of user topic interests and social preferences,thereby providing a more realistic refection of user attributes.Additionally,to enhance the robustness of feature modeling,we introduce a variant of the temporal adapter that implements multiple temporal adaptations in parallel while maintaining structural simplicity.Experimental results on real-world datasets demonstrate that the ALL-RP model surpasses state-of-the-art models in predicting both individual user reposting behavior and group sharing behavior,with performance gains of 2.81%and 4.29%,respectively. 展开更多
关键词 Reposting prediction large language model semantic adaptation temporal adaptation
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Could Plant Height Compensate for Temporal and Spatial Limitations of Canopy Spectra for Inversion of Plant Nitrogen Accumulation in Rice?
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作者 WANG Xiaoke XU Guiling +7 位作者 FENG Yuehua SONG Zhengli GUO Yanjun Muhammad Usama LATIF LU Linya Somsana PHONENASAY XU Xiangjun CUI BingPing 《Rice science》 2025年第4期467-471,I0037-I0042,共11页
Recently,information acquired at the canopy top,such as spectral and textural data,has been widely used to estimate plant nitrogen(N)accumulation(PNA).The response of crops to N uptake involves not only changes in hor... Recently,information acquired at the canopy top,such as spectral and textural data,has been widely used to estimate plant nitrogen(N)accumulation(PNA).The response of crops to N uptake involves not only changes in horizontal canopy top information but also an increase in vertical plant height(PH).It remains unclear whether the fusion of spectral indices with PH can improve the estimation performance of PNA models based on spectral remote sensing across different growth stages. 展开更多
关键词 temporal limitations RICE nitrogen accumulation canopy top information spatial limitations plant height spectral remote sensing canopy spectra
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