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Dynamic Spatio-Temporal Modeling in Disease Mapping
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作者 Flavian Awere Otieno Cox Lwaka Tamba +1 位作者 Justin Obwoge Okenye Luke Akong’o Orawo 《Open Journal of Statistics》 2023年第6期893-916,共24页
Spatio-temporal models are valuable tools for disease mapping and understanding the geographical distribution of diseases and temporal dynamics. Spatio-temporal models have been proven empirically to be very complex a... Spatio-temporal models are valuable tools for disease mapping and understanding the geographical distribution of diseases and temporal dynamics. Spatio-temporal models have been proven empirically to be very complex and this complexity has led many to oversimply and model the spatial and temporal dependencies independently. Unlike common practice, this study formulated a new spatio-temporal model in a Bayesian hierarchical framework that accounts for spatial and temporal dependencies jointly. The spatial and temporal dependencies were dynamically modelled via the matern exponential covariance function. The temporal aspect was captured by the parameters of the exponential with a first-order autoregressive structure. Inferences about the parameters were obtained via Markov Chain Monte Carlo (MCMC) techniques and the spatio-temporal maps were obtained by mapping stable posterior means from the specific location and time from the best model that includes the significant risk factors. The model formulated was fitted to both simulation data and Kenya meningitis incidence data from 2013 to 2019 along with two covariates;Gross County Product (GCP) and average rainfall. The study found that both average rainfall and GCP had a significant positive association with meningitis occurrence. Also, regarding geographical distribution, the spatio-temporal maps showed that meningitis is not evenly distributed across the country as some counties reported a high number of cases compared with other counties. 展开更多
关键词 spatio-temporal model Matern Exponential Covariance Function Spatial and Temporal Dependencies Markov Chain Monte Carlo (MCMC)
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Spatio-temporal model for soil characteristic of reclamation land
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作者 CHEN Qiu-ji HU Zhen-qi +2 位作者 FU Mei-chen XIE Hong-quan HAO Hai-fu 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期45-48,共4页
The development of spatio-temporal data model is introduced.According to the soil characteristic of reclamation land,we adopt the base state with amendments model of multi-layer raster to organize the spatio-temporal ... The development of spatio-temporal data model is introduced.According to the soil characteristic of reclamation land,we adopt the base state with amendments model of multi-layer raster to organize the spatio-temporal data,using the combined data structure on linear quadtree and linear octree to code.The advantage of this model is that it can easily obtain the information of certain layer and integratedly analyze the data with other methods.Then,the methods of obtain and analyses are introduced.The method can provide a tool for the research of the soil characteristic change and spatial distribution in reclamation land. 展开更多
关键词 reclamation soil spatio-temporal data model linear quad-tree linear octree
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The spatio-temporal models of periodic marketing in rural China
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作者 LIU Sheng-he(Institute of Geography, Chinese Academy of Sciences. Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第4期335-345,共11页
Periodic marketing is a unique and imporant socio-economic feature of Chinese ruraltowns, the economic, political, social and cultural centres in rural areas. Through two detailed casestudies in the North China Plain... Periodic marketing is a unique and imporant socio-economic feature of Chinese ruraltowns, the economic, political, social and cultural centres in rural areas. Through two detailed casestudies in the North China Plain in 1990, mis paper examined the temporal and spatialcharacteristics, especially their interrelationship. of regional periodic market systems and theirrelationship with rural development in modern China. The distribution of periodic market-towns isfound to be on consumer convenience, and to have an apparent hierarchical structure and centralplace characteristics. Further, the spatial coordination system of periodic marketing has a reverserelationship of spatio-temporal synchronisation. Finally, this paper notes that periodic marketingimposes significant influence on rural development through conducting and controlling goods flow and population flow in rural economic system. 展开更多
关键词 Periodic marketing spatio-temporal synchronisation rural development
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Bayesian spatio-temporal modeling of severe acute respiratory syndrome in Brazil:A comparative analysis across pre-,during,and post-COVID-19 eras
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作者 Rodrigo de Souza Bulhões Jonatha Sousa Pimentel Paulo Canas Rodrigues 《Infectious Disease Modelling》 2025年第2期466-476,共11页
This paper presents an investigation into the spatio-temporal dynamics of Severe Acute Respiratory Syndrome(SARS)across the diverse health regions of Brazil from 2016 to 2024.Leveraging extensive datasets that include... This paper presents an investigation into the spatio-temporal dynamics of Severe Acute Respiratory Syndrome(SARS)across the diverse health regions of Brazil from 2016 to 2024.Leveraging extensive datasets that include SARS cases,climate data,hospitalization records,and COVID-19 vaccination information,our study employs a Bayesian spatio-temporal generalized linear model to capture the intricate dependencies inherent in the dataset.The analysis reveals significant variations in the incidence of SARS cases over time,particularly during and between the distinct eras of pre-COVID-19,during,and post-COVID-19.Our modeling approach accommodates explanatory variables such as humidity,temperature,and COVID-19 vaccine doses,providing a comprehensive understanding of the factors influencing SARS dynamics.Our modeling revealed unique temporal trends in SARS cases for each region,resembling neighborhood patterns.Low temperature and high humidity were linked to decreased cases,while in the COVID-19 era,temperature and vaccination coverage played significant roles.The findings contribute valuable insights into the spatial and temporal patterns of SARS in Brazil,offering a foundation for targeted public health interventions and preparedness strategies. 展开更多
关键词 spatio-temporal generalized linear model for areal unit data Bayesian spatio-temporal modeling Severe acute respiratory syndrome COVID-19 Brazilian health regions
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Bi-STAT+:An Enhanced Bidirectional Spatio-Temporal Adaptive Transformer for Urban Traffic Flow Forecasting
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作者 Yali Cao Weijian Hu +3 位作者 Lingfang Li Minchao Li Meng Xu Ke Han 《Computers, Materials & Continua》 2026年第2期963-985,共23页
Traffic flow prediction constitutes a fundamental component of Intelligent Transportation Systems(ITS),playing a pivotal role in mitigating congestion,enhancing route optimization,and improving the utilization efficie... Traffic flow prediction constitutes a fundamental component of Intelligent Transportation Systems(ITS),playing a pivotal role in mitigating congestion,enhancing route optimization,and improving the utilization efficiency of roadway infrastructure.However,existingmethods struggle in complex traffic scenarios due to static spatio-temporal embedding,restricted multi-scale temporal modeling,and weak representation of local spatial interactions.This study proposes Bi-STAT+,an enhanced bidirectional spatio-temporal attention framework to address existing limitations through three principal contributions:(1)an adaptive spatio-temporal embedding module that dynamically adjusts embeddings to capture complex traffic variations;(2)frequency-domain analysis in the temporal dimension for simultaneous high-frequency details and low-frequency trend extraction;and(3)an agent attention mechanism in the spatial dimension that enhances local feature extraction through dynamic weight allocation.Extensive experiments were performed on four distinct datasets,including two publicly benchmark datasets(PEMS04 and PEMS08)and two private datasets collected from Baotou and Chengdu,China.The results demonstrate that Bi-STAT+consistently outperforms existing methods in terms of MAE,RMSE,and MAPE,while maintaining strong robustness against missing data and noise.Furthermore,the results highlight that prediction accuracy improves significantly with higher sampling rates,providing crucial insights for optimizing real-world deployment scenarios. 展开更多
关键词 Traffic flow prediction spatio-temporal feature modeling TRANSFORMER intelligent transportation deep learning
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Spatio-temporal resolutions of charge transfer reactions in the Li-ion battery studied by electrochemical impedance spectroscopy
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作者 Zijie Wu Qiu-An Huang +2 位作者 Yuxuan Bai Jiujun Zhang Kai Wu 《Journal of Energy Chemistry》 2026年第1期1026-1045,I0022,共21页
The pseudo-two-dimensional(P2D)model plays an important role in exploring physicochemical mechanisms,predicting the state of health,and improving the fast charge capability for Li-ion batteries(LIBs).However,the fast ... The pseudo-two-dimensional(P2D)model plays an important role in exploring physicochemical mechanisms,predicting the state of health,and improving the fast charge capability for Li-ion batteries(LIBs).However,the fast charge leads to the lithium concentration gradient in the solid and electrolyte phases and the non-uniform electrochemical reaction at the solid/electrolyte interface.In order to decouple charge transfer reactions in LIBs under dynamic conditions,understanding the spatio-temporal resolution of the P2D model is urgently required.Till now,the study of this aspect is still insufficient.This work studies the spatio-temporal resolution for dynamic/static electrochemical impedance spectroscopy(DEIS/SEIS)on multiple scales.In detail,DEIS and SEIS with spatio-temporal resolutions are used to decouple charge transfer reactions in LIBs based on the numerical solution of the P2D model in the frequency domain.The calculated results indicate that decoupling solid diffusion requires a high spatial resolution along the r-direction in particles,decoupling electrolyte diffusion and interfacial transfer reaction requires a high spatial resolution along the x-direction,and decoupling charge transfer reactions in LIBs at an extremely low state of charge(SOC)requires an extremely high temporal resolution along the t-direction.Finally,the optimal range of spatio-temporal resolutions for DEIS/SEIS is derived,and the method to decouple charge transfer reactions with spatio-temporal resolutions is developed. 展开更多
关键词 spatio-temporal resolution Discretization grid Electrochemical impedance spectroscopy Pseudo-two-dimensional model Li-ion battery
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Spatio-temporal impacts of land use patterns on habitat quality:A multi-scenario development analysis
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作者 GUO Yue ZHANG Yubo WEN Changji 《智能化农业装备学报(中英文)》 2026年第1期178-189,共12页
As a tropical island confronting the dual imperatives of tourism-driven economic growth and ecological vulnerability,Hainan's land-use sustainability critically impacts both regional development and coastal ecosys... As a tropical island confronting the dual imperatives of tourism-driven economic growth and ecological vulnerability,Hainan's land-use sustainability critically impacts both regional development and coastal ecosystem security.This study employs a coupled PLUS-InVEST modeling framework to analyze land-use changes and habitat quality dynamics from 2000 to 2020,projecting ecological outcomes under three development scenarios for 2030.Key findings reveal:(1)A persistent bimodal habitat distribution pattern,with high-quality areas concentrated in the central forest zone and degraded areas in coastal peripheries,exhibiting a continuous decline over the 20-year period.(2)Accelerated urbanization between 2010 and 2020 resulted in the conversion of ecological land to construction use,correlating strongly with habitat fragmentation intensity.(3)Baseline projections for 2030 indicate that construction land will dominate new conversions.(4)Ecological protection scenarios demonstrate recoverable habitat potentials,particularly within coastal buffer zones.These findings provide empirical validation of scenario-driven land-use planning as a viable tool for island ecosystems,highlighting the critical need to balance tourism infrastructure development with coastal conservation imperatives in tropical island sustainability management.This methodology advances spatial decision-making for balancing island economic growth with biodiversity preservation,offering replicable strategies for global island ecosystems facing similar sustainability challenges. 展开更多
关键词 land use change habitat quality InVEST model PLUS model multi-scenario prediction
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Spatio-Temporal Graph Neural Networks with Elastic-Band Transform for Solar Radiation Prediction
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作者 Guebin Choi 《Computer Modeling in Engineering & Sciences》 2026年第1期848-872,共25页
This study proposes a novel forecasting framework that simultaneously captures the strong periodicity and irregular meteorological fluctuations inherent in solar radiation time series.Existing approaches typically def... This study proposes a novel forecasting framework that simultaneously captures the strong periodicity and irregular meteorological fluctuations inherent in solar radiation time series.Existing approaches typically define inter-regional correlations using either simple correlation coefficients or distance-based measures when applying spatio-temporal graph neural networks(STGNNs).However,such definitions are prone to generating spurious correlations due to the dominance of periodic structures.To address this limitation,we adopt the Elastic-Band Transform(EBT)to decompose solar radiation into periodic and amplitude-modulated components,which are then modeled independently with separate graph neural networks.The periodic component,characterized by strong nationwide correlations,is learned with a relatively simple architecture,whereas the amplitude-modulated component is modeled with more complex STGNNs that capture climatological similarities between regions.The predictions from the two components are subsequently recombined to yield final forecasts that integrate both periodic patterns and aperiodic variability.The proposed framework is validated with multiple STGNN architectures,and experimental results demonstrate improved predictive accuracy and interpretability compared to conventional methods. 展开更多
关键词 spatio-temporal graph neural network(STGNN) elastic-band transform(EBT) solar radiation fore-casting spurious correlation time series decomposition
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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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Spatio-temporal evolution patterns and type differentiation of potential land use conflicts in China
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作者 ZONG Shanshan XU Shan +1 位作者 KE Qinhua JIANG Xinyao 《Journal of Geographical Sciences》 2026年第2期321-340,共20页
Land use conflicts(LUCs)pose a major challenge to urbanization,and their effective regulation is essential for promoting sustainable regional land use.However,the influence of urban development on conflicts has often ... Land use conflicts(LUCs)pose a major challenge to urbanization,and their effective regulation is essential for promoting sustainable regional land use.However,the influence of urban development on conflicts has often been overlooked.This study developed an index system from three dimensions—agricultural production,residential life,and ecological security—and quantified LUCs in China using spatial statistics and a coupling relationship matrix.It further explored the spatial relationships between conflict types and urban built-up areas(UBA)through accessibility analysis,and applied regression analysis to reveal the spatial evolution of conflicts from an urban-scale perspective.The results showed that agricultural-construction conflicts were concentrated in the eastern plains,while agricultural-ecological conflicts prevailed in the mountainous areas in the western region.Spatial distribution of the distance from conflicts to UBA(DCU)exhibited a clear east-west gradient,being closer in the east(less than 20 km)and farther in the west.Between 2000 and 2020,LUCs moved progressively closer to UBA,except in the ecologically fragile western region.For all urban hierarchies except small cities,the average distance was below 10 km;megacities exhibited the shortest DCU,roughly half that of small cities.Moreover,LUCs displayed significant hierarchical scale effects:as urban size increased,distance tended to decrease in a non-linear pattern,with the steepest decline occurring in central China.Land management authorities should work to curb sprawling urban development.Overall,this study provides new insights into the spatial evolution of LUCs and contributes to more sustainable land use management. 展开更多
关键词 potential land use conflicts urban built-up areas Euclidean distance model urban scale China
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On Spatio-Temporal Model with Diverging Number of Thresholds and its Applications in Housing Market
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作者 Baisuo Jin Yaguang Li Yuehua Wu 《Communications in Mathematics and Statistics》 2025年第3期571-606,共36页
Spatio-temporal data analysis is an emerging research area due to the development and application ofnovel computational techniques allowing for the analysis of large spatiotemporal databases.We consider a general clas... Spatio-temporal data analysis is an emerging research area due to the development and application ofnovel computational techniques allowing for the analysis of large spatiotemporal databases.We consider a general class of spatio-temporal linear models,where the number of structural breaks can tend to infinity.A procedure for simultaneously detecting all the change points is developed rigorously via the construction of adaptive group lasso penalty.Consistency of the multiple change point estimation is established under mild technical conditions even when the true number of change points sn diverges with the series length n.The adaptive group lasso can be substituted by the group lasso and other non-convex group selection penalty functions such as group SCAD or group MCP.The simulation studies demonstrate that our procedure is stable and accurate.Two empirical examples from property market,including the housing transaction price in Baton Rouge and the commodity apartment price in Hong Kong,are analyzed to fully illustrate the proposed methodology. 展开更多
关键词 Change points Balanced panel data dynamic linear models Group selection Real estate market spatio-temporal data
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State Space Guided Spatio-Temporal Network for Efficient Long-Term Traffic Prediction
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作者 Guangyu Huo Chang Su +2 位作者 Xiaoyu Zhang Xiaohui Cui Lizhong Zhang 《Computers, Materials & Continua》 2026年第2期1242-1264,共23页
Long-term traffic flow prediction is a crucial component of intelligent transportation systems within intelligent networks,requiring predictive models that balance accuracy with low-latency and lightweight computation... Long-term traffic flow prediction is a crucial component of intelligent transportation systems within intelligent networks,requiring predictive models that balance accuracy with low-latency and lightweight computation to optimize trafficmanagement and enhance urban mobility and sustainability.However,traditional predictivemodels struggle to capture long-term temporal dependencies and are computationally intensive,limiting their practicality in real-time.Moreover,many approaches overlook the periodic characteristics inherent in traffic data,further impacting performance.To address these challenges,we introduce ST-MambaGCN,a State-Space-Based Spatio-Temporal Graph Convolution Network.Unlike conventionalmodels,ST-MambaGCN replaces the temporal attention layer withMamba,a state-space model that efficiently captures long-term dependencies with near-linear computational complexity.The model combines Chebyshev polynomial-based graph convolutional networks(GCN)to explore spatial correlations.Additionally,we incorporate a multi-temporal feature capture mechanism,where the final integrated features are generated through the Hadamard product based on learnable parameters.This mechanism explicitly models shortterm,daily,and weekly traffic patterns to enhance the network’s awareness of traffic periodicity.Extensive experiments on the PeMS04 and PeMS08 datasets demonstrate that ST-MambaGCN significantly outperforms existing benchmarks,offering substantial improvements in both prediction accuracy and computational efficiency for long-term traffic flow prediction. 展开更多
关键词 State space model long-term traffic flow prediction graph convolutional network multi-time scale analysis emerging applications at intelligent networks
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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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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 epidemic type aftershock sequence model for Tangshan aftershock sequence
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作者 Shaochuan Lue Yong Li 《Earthquake Science》 CSCD 2011年第5期401-408,共8页
Shallow earthquakes usually show obvious spatio-temporal clustering patterns. In this study, several spatio-temporal point process models are applied to investigate the clustering characteristics of the well-known Tan... Shallow earthquakes usually show obvious spatio-temporal clustering patterns. In this study, several spatio-temporal point process models are applied to investigate the clustering characteristics of the well-known Tangshan sequence based on classical empirical laws and a few assumptions. The relative fit of competing models is compared by Akalke Information Criterion. The spatial clustering pattern is well characterized by the model which gives the best fit to the data. A simulated aftershock sequence is generated by thinning algorithm and compared with the real seismicity. 展开更多
关键词 spatio-temporal model Tangshan aftershock sequence Laplace type clustering thinning simulation Akaike information criterion
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Constructing a raster-based spatio-temporal hierarchical data model for marine fisheries application 被引量:2
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作者 SU Fenzhen ZHOU Chenhu ZHANG Tianyu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期57-63,共7页
Marine information has been increasing quickly. The traditional database technologies have disadvantages in manipulating large amounts of marine information which relates to the position in 3-D with the time. Recently... Marine information has been increasing quickly. The traditional database technologies have disadvantages in manipulating large amounts of marine information which relates to the position in 3-D with the time. Recently, greater emphasis has been placed on GIS (geographical information system)to deal with the marine information. The GIS has shown great success for terrestrial applications in the last decades, but its use in marine fields has been far more restricted. One of the main reasons is that most of the GIS systems or their data models are designed for land applications. They cannot do well with the nature of the marine environment and for the marine information. And this becomes a fundamental challenge to the traditional GIS and its data structure. This work designed a data model, the raster-based spatio-temporal hierarchical data model (RSHDM), for the marine information system, or for the knowledge discovery fi'om spatio-temporal data, which bases itself on the nature of the marine data and overcomes the shortages of the current spatio-temporal models when they are used in the field. As an experiment, the marine fishery data warehouse (FDW) for marine fishery management was set up, which was based on the RSHDM. The experiment proved that the RSHDM can do well with the data and can extract easily the aggregations that the management needs at different levels. 展开更多
关键词 marine geographical information system spatio-temporal data model knowledge discovery fishery management data warehouse
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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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A Spatio-temporal Data Model for Road Network in Data Center Based on Incremental Updating in Vehicle Navigation System 被引量:1
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作者 WU Huisheng LIU Zhaoli +1 位作者 ZHANG Shuwen ZUO Xiuling 《Chinese Geographical Science》 SCIE CSCD 2011年第3期346-353,共8页
The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation sy... The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation system is in charge of storing incremental data,and the spatio-temporal data model for storing incremental data does affect the efficiency of the response of the data center to the requirements of incremental data from the vehicle terminal.According to the analysis on the shortcomings of several typical spatio-temporal data models used in the data center and based on the base map with overlay model,the reverse map with overlay model (RMOM) was put forward for the data center to make rapid response to incremental data request.RMOM supports the data center to store not only the current complete road network data,but also the overlays of incremental data from the time when each road network changed to the current moment.Moreover,the storage mechanism and index structure of the incremental data were designed,and the implementation algorithm of RMOM was developed.Taking navigational road network in Guangzhou City as an example,the simulation test was conducted to validate the efficiency of RMOM.Results show that the navigation database in the data center can response to the requirements of incremental data by only one query with RMOM,and costs less time.Compared with the base map with overlay model,the data center does not need to temporarily overlay incremental data with RMOM,so time-consuming of response is significantly reduced.RMOM greatly improves the efficiency of response and provides strong support for the real-time situation of navigational road network. 展开更多
关键词 spatio-temporal data model reverse map with overlay model road network incremental updating vehicle navigation system data center vehicle terminal
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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 in the Rice Planting Area and Their Relationship to Climate Change in Northeast China: A Model-Based Analysis 被引量:18
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作者 XIA Tian WU Wen-bin +5 位作者 ZHOU Qing-bo YU Qiang-yi Peter H Verburg YANG Peng LU Zhong-jun TANG Hua-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第7期1575-1585,共11页
Rice is one of the most important grain crops in Northeast China (NEC) and its cultivation is sensitive to climate change. This study aimed to explore the spatio-temporal changes in the NEC rice planting area over t... Rice is one of the most important grain crops in Northeast China (NEC) and its cultivation is sensitive to climate change. This study aimed to explore the spatio-temporal changes in the NEC rice planting area over the period of 1980-2010 and to analyze their relationship to climate change. To do so, the CLUE-S (conversion of land use and its effects at small region extent) model was ifrst updated and used to simulate dynamic changes in the rice planting area in NEC to understand spatio-temporal change trends during three periods: 1980-1990, 1990-2000 and 2000-2010. The changing results in individual periods were then linked to climatic variables to investigate the climatic drivers of these changes. Results showed that the NEC rice planting area expanded quickly and increased by nearly 4.5 times during 1980-2010. The concentration of newly planted rice areas in NEC constantly moved northward and the changes were strongly dependent on latitude. This conifrmed that climate change, increases in temperature in particular, greatly inlfuenced the shift in the rice planting area. The shift in the north limit of the NEC rice planting area generally followed a 1&#176;C isoline migration pattern, but with an obvious time-lag effect. These ifndings can help policy makers and crop producers take proper adaptation measures even when exposed to the global warming situation in NEC. 展开更多
关键词 spatio-temporal change rice planting area climate change Northeast China
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