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Spatial-Temporal Dynamics of Dongzhaigang Mangrove Forests on Hainan Island,China:Evidence from Landsat Observations(1988–2019)
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作者 Bing Tu Kang Peng +4 位作者 Xianjun Xie Lu Yan Yamin Deng Yiqun Gan Qinghua Li 《Journal of Earth Science》 2026年第1期289-302,共14页
The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang... The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem. 展开更多
关键词 mangrove forests spatial-temporal data Hainan Island decision trees Landsat image
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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-temporal Dynamics and Driving Forces of Land Development Intensity in the Western China from 2000 to 2015 被引量:23
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作者 HUANG Xin HUANG Xiaojun +2 位作者 LIU Mengmeng WANG Bo ZHAO Yonghua 《Chinese Geographical Science》 SCIE CSCD 2020年第1期16-29,共14页
The change in land development intensity is an important perspective to reflect the variation in regional social and economic development and spatial differentiation.In this paper,spatial statistical analysis,Ordinary... The change in land development intensity is an important perspective to reflect the variation in regional social and economic development and spatial differentiation.In this paper,spatial statistical analysis,Ordinary Least Squares(OLS),and Geographically weighted regression(GWR)methods are used to systematically analyse the spatial-temporal characteristics and driving forces of land development intensity for 131 spatial units in the western China from 2000 to 2015.The findings of the study are as follows:1)The land development intensity in the western China has been increasing rapidly.From 2000 to 2015,land development intensity increased by 3.4 times on average.2)The hotspot areas have shifted from central Inner Mongolia,northern Shaanxi and the Beibu Gulf of Guangxi to the Guanzhong Plain and the Chengdu-Chongqing urban agglomeration.The areas of cold spots were mainly concentrated in the Qinghai-Tibet Plateau,Yunnan,and Xinjiang.3)Investment intensity and the natural environment have always been the main drivers of land development intensity in the western China.Investment played a powerful role in promoting land development intensity,while the natural and ecological environment distinctly constrained such development.The effect of the economic factors on land development intensity in the western China has changed,which is reflected in the driving factor of construction land development shifting from economic growth in 2000 to economic structure,especially industrial structure,in 2015. 展开更多
关键词 construction land land development intensity spatial-temporal dynamic driving force the western China
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SPATIAL-TEMPORAL DYNAMICS OF REGIONAL CONVERGENCE AT COUNTY LEVEL IN JIANGSU 被引量:3
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作者 PUYing-xia MARong-hua +1 位作者 GEYing HUANGXing-yuan 《Chinese Geographical Science》 SCIE CSCD 2005年第2期113-119,共7页
The dynamics of regional convergence include spatial and temporal dimensions. Spatial Markov chain can be used to explore how regions evolve by considering both individual regions and their geographic neighbors. Based... The dynamics of regional convergence include spatial and temporal dimensions. Spatial Markov chain can be used to explore how regions evolve by considering both individual regions and their geographic neighbors. Based on per capita GDP data set of 77 counties from 1978 to 2000, this paper attempts to investigate the spatial-temporal dynamics of regional convergence in Jiangsu. First, traditional Markov matrix for five per capita GDP classes is constructed for later comparison. Moreover, each region’s spatial lag is derived by averaging all its neighbors’ per capita GDP data. Conditioning on per capita GDP class of its spatial lag at the beginning of each year, spatial Markov transition probabilities of each region are calculated accordingly. Quantitatively, for a poor region, the probability of moving upward is 3.3% if it is surrounded by its poor neighbors, and even increases to 18.4% if it is surrounded by its rich neighbors, but it goes down to 6.2% on average if ignoring regional context. For a rich region, the probability of moving down ward is 1.2% if it is surrounded by its rich neighbors, but increases to 3.0% if it is surrounded by its poor neighbors, and averages 1.5% irrespective of regional context. Spatial analysis of regional GDP class transitions indicates those 10 upward moves of both regions and their neighbors are unexceptionally located in the southern Jiangsu, while downward moves of regions or their neighbors are almost in the northern Jiangsu. These empirical results provide a spatial explanation to the "convergence clubs" detected by traditional Markov chain. 展开更多
关键词 regional convergence spatial-temporal dynamics spatial Markov chain Jiangsu Province
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Spatial-temporal dynamics of desert vegetation and its responses to climatic variations over the last three decades:a case study of Hexi region in Northwest China 被引量:15
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作者 YANG Xuemei LIU Shizeng +6 位作者 YANG Taibao XU Xianying KANG Caizhou TANG Jinnian WEI Huaidong Mihretab G GHEBREZGABHER LI Zhiqi 《Journal of Arid Land》 SCIE CSCD 2016年第4期556-568,共13页
Analysis of spatial-temporal variations of desert vegetation under the background of climate changes can provide references for ecological restoration in arid and semi-arid areas. In this study, we used the Global Inv... Analysis of spatial-temporal variations of desert vegetation under the background of climate changes can provide references for ecological restoration in arid and semi-arid areas. In this study, we used the Global Inventory Modeling and Mapping Studies (GIMMS) NDVI data from 1982 to 2006 and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data from 2000 to 2013 to reveal the dynamics of desert vegetation in Hexi region of Northwest China over the past three decades. We also used the annual temperature and precipitation data acquired from the Chinese meteorological stations to analyze the response of desert vegetation to climatic variations. The average value of NDVImax (the maximum NDVI during the growing season) for desert vegetation in Hexi region increased at the rate of 0.65x10-3/a (P〈0.05) from 1982 to 2013, and the significant increases of NDVImax mainly appeared in the typical desert vegetation areas. Vegetation was significantly improved in the lower reaches of Shule and Shiyang river basins, and the weighted mean center of desert vegetation mainly shifted toward the lower reaches of the two basins. Almost 95.32% of the total desert vegetation area showed positive correlation between NDVImax and annual precipitation, indicating that precipitation is the key factor for desert vegetation growth in the entire study area. Moreover, the areas with non-significant positive correlation between NDVImax and annual precipitation mainly located in the lower reaches of Shiyang and Shule river basins, this may be due to human activities. Only 7.64% of the desert vegetation showed significant positive correlation between NDVImax and annual precipitation in the Shule River Basin (an extremely arid area), indicating that precipitation is not the most important factor for vegetation growth in this basin, and further studies are needed to investigate the mechanism for this phenomenon. 展开更多
关键词 desert vegetation NDVI global warming spatial-temporal variations Hexi region
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Evaluation of spatial-temporal dynamics in surface water temperature of Qinghai Lake from 2001 to 2010 by using MODIS data 被引量:16
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作者 Fei XIAO Feng LING +3 位作者 Yun DU Qi FENG Yi YAN Hui CHEN 《Journal of Arid Land》 SCIE CSCD 2013年第4期452-464,共13页
Lake surface water temperature (SWT) is an important indicator of lake state relative to its water chemistry and aquatic ecosystem,in addition to being an important regional climate indicator.However,few literatures... Lake surface water temperature (SWT) is an important indicator of lake state relative to its water chemistry and aquatic ecosystem,in addition to being an important regional climate indicator.However,few literatures involving spatial-temporal changes of lake SWT in the Qinghai-Tibet Plateau,including Qinghai Lake,are available.Our objective is to study the spatial-temporal changes in SWT of Qinghai Lake from 2001 to 2010,using Moderate-resolution Imaging Spectroradiometer (MODIS) data.Based on each pixel,we calculated the temporal SWT variations and long-term trends,compared the spatial patterns of annual average SWT in different years,and mapped and analyzed the seasonal cycles of the spatial patterns of SWT.The results revealed that the differences between the average daily SWT and air temperature during the temperature decreasing phase were relatively larger than those during the temperature increasing phase.The increasing rate of the annual average SWT during the study period was about 0.01℃/a,followed by an increasing rate of about 0.05℃/a in annual average air temperature.The annual average SWT from 2001 to 2010 showed similar spatial patterns,while the SWT spatial changes from January to December demonstrated an interesting seasonal reversion pattern.The high-temperature area transformed stepwise from the south to the north regions and then back to the south region from January to December,whereas the low-temperature area demonstrated a reversed annual cyclical trace.The spatial-temporal patterns of SWTs were shaped by the topography of the lake basin and the distribution of drainages. 展开更多
关键词 surface water temperature (SWT) spatial-temporal changes MODIS Qinghai Lake
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The spatial-temporal dynamic characteristics of the marsh in the Sanjiang Plain 被引量:5
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作者 ZHANGBai ZHANGShuqing +1 位作者 WANGAihua ZHANGJunyan 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期201-207,共7页
Using the methods of combining landscape ecology with GIS spatial analysis, this paper analyses the dynamics of the marsh landscape structure of the Sanjiang Plain in the past 20 years, fu... Using the methods of combining landscape ecology with GIS spatial analysis, this paper analyses the dynamics of the marsh landscape structure of the Sanjiang Plain in the past 20 years, furthermore, taking Fujin County, located in the north of the plain, as an example, analyzes the conversion between marsh and other land use types. It is shown that the marsh in the Sanjiang Plain decreased greatly in the past 20 years, but the trend has begun to reverse. The marsh area decreased by 51.33% from 1980 to 1996, whereas it decreased by 4.19% from 1996 to 2000. The fragmentation of the marsh increased; the number of the patches increased by 326 from 1986 to 1996, whereas it only increased by 18 patches from 1996 to 2000. It is obvious that the speed of patches number diminished and the marsh fragmentation decreased, which shows that the reclamation of the marsh converted from the fragmentation to the brim in a large area of the marsh. The reclaimed marsh has mainly converted to paddy field and dry land. Large-scale reclamation in the Sanjiang Plain influences its natural environment directly: the climate of the region turns from cold and wet to warm and dry, which makes the marsh both in the low-temperature northern part and in the deeply stagnant eastern part suitable for further agricultural development. 展开更多
关键词 MARSH spatial and temporal dynamics wetland management landscape change remote sensing CLC number:F301.24 P942.3.78
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Spatial-temporal dynamics of alpine grassland coverage and its response to climate warming in Mt.Qomolangma Nature Preserve during 2000-2019 被引量:2
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作者 MA Fei PENG Pei-hao 《Journal of Mountain Science》 SCIE CSCD 2022年第8期2297-2311,共15页
The Qinghai-Tibet Plateau(QTP)has the largest and highest alpine grassland ecosystem in the world,which is considered to be the most sensitive and vulnerable ecosystem to climate change.Its dynamic changes and driving... The Qinghai-Tibet Plateau(QTP)has the largest and highest alpine grassland ecosystem in the world,which is considered to be the most sensitive and vulnerable ecosystem to climate change.Its dynamic changes and driving mechanism have always been widely researched.The Qomolangma National Nature Preserve(QNNP),with the largest altitude difference in the world,was selected as the study area to analyse the spatial-temporal dynamics of grassland coverage and the different characteristics of elevation gradients at the southern slope(SS)and northern slope(NS)with MODIS MOD13Q1 NDVI and MOD11A2 land surface temperature data from 2000to 2019 using the Mann-Kendall trend test and Theil-Sen slope methods.Further,the response mechanism of grassland coverage to climate warming is discussed.The results revealed that from 2000 to 2019,the grassland coverage change in the study area is mainly stable.The increased area proportion of grassland coverage on the southern slope is significantly higher than that on the northern slope,and the decreased area proportion of grassland coverage on the northern slope is significantly greater than that on the southern slope.The change characteristics of grassland coverage in the QNNP exhibit an obvious elevation gradient;the higher the elevation,the greater the increased area proportion of grassland coverage,particularly on the SS.The land surface temperature can be used as a proxy for analysing the temporal and spatial variation trends of air temperature in the QNNP.With the increase of the altitude,the land surface temperature rise rate on both the southern slope and northern slope exhibited an increasing trend,and the sensitivity of grassland coverage to temperature rise was higher on the northern slope.The water condition was the decisive factor for the horizontal and vertical spatial heterogeneity of the dynamic change of grassland coverage,and the melting of glaciers and thawing of permafrost were important sources of water for grassland growth in the QNNP.Climate warming promotes the growth of grassland in areas with a sufficient water supply,but adversely affects the growth of grassland in areas with insufficient water supplies,which will be further intensified by human activities. 展开更多
关键词 Alpine grassland Global warming Vegetation dynamic Elevation gradient Qomolangma
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Spatial-Temporal Dynamics of Runoff Generation Areas in a Small Agricultural Watershed in Southern Ontario
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作者 Kamran Chapi Ramesh P. Rudra +4 位作者 Syed I. Ahmed Alamgir A. Khan Bahram Gharabaghi William T. Dickinson Pradeep K. Goel 《Journal of Water Resource and Protection》 2015年第1期14-40,共27页
The identification of runoff generating areas (RGAs) within a watershed is a difficult task because of their temporal and spatial behavior. A watershed was selected to investigate the RGAs to determine the factors aff... The identification of runoff generating areas (RGAs) within a watershed is a difficult task because of their temporal and spatial behavior. A watershed was selected to investigate the RGAs to determine the factors affecting spatio-temporally in southern Ontario. The watershed was divided into 8 fields having a Wireless System Network (WSN) and a V-notch weir for flow and soil moisture measurements. The results show that surface runoff is generated by the infiltration excess mechanism in summer and fall, and the saturation excess mechanism in spring. The statistical analysis suggested that the amount of rainfall and rainfall intensity for summer (R2 = 0.63, 0.82) and fall (R2 = 0.74, 0.80), respectively, affected the RGAs. The analysis showed that 15% area generated 85% of surface runoff in summer, 100% of runoff in fall, and 40% of runoff in spring. The methodology developed has potential for identifying RGAs for protecting Ontario’s water resources. 展开更多
关键词 VARIABLE SOURCE Area RUNOFF spatial-temporal VARIABILITY SEASONAL Effect
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SalicS1 FRET sensor enables real-time visualization of salicylic acid dynamics in plant immunity
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作者 Shengmei Kang Qiyuan Zhang Feng Wang 《Advanced Agrochem》 2026年第1期7-9,共3页
SalicS1 is a genetically encoded,ratiometric FRET biosensor that brings salicylic acid(SA)research to the same real-time imaging standard long available for ABA and GA.Built through a modular Golden Gate platform and ... SalicS1 is a genetically encoded,ratiometric FRET biosensor that brings salicylic acid(SA)research to the same real-time imaging standard long available for ABA and GA.Built through a modular Golden Gate platform and informed by NPR-NIMIN structural biology,SalicS1 achieves SA specificity,tunable affinity,reversibility,and non-perturbing expression in Arabidopsis.Using this sensor,pathogen infection,non-adapted fungal challenge,and aphid feeding are shown to elicit spatially propagating SA surges rather than purely local accumulation,revealing a tissue-level organization of immune signaling that bulk assays could not resolve.SalicS1 therefore provides a broadly deployable tool for dissecting the geometry,timing,and genotype dependence of SA-mediated plant defense. 展开更多
关键词 SalicS1 FRET biosensor Salicylic acid dynamics Plant immunity spatial-temporal imaging
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A novel deviation measurement for scheduled intelligent transportation system via comparative spatial-temporal path networks
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作者 Daozhong Feng Jiajian Lai +1 位作者 Wenxuan Wei Bin Hao 《Digital Communications and Networks》 2026年第1期101-118,共18页
Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-netwo... Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-network description technologies are ineffective in representing the temporal and spatial characteristics simultaneously.Therefore,there is a need for complementary methods to address these deficiencies.To address these limitations,this paper proposes an approach that combines Network Snapshots and Temporal Paths for the scheduled system.A dual information network is constructed to assess the degree of operational deviation considering the planning tasks.To validate the effectiveness,discussions are conducted through a modified cosine similarity calculation on theoretical analysis,delay level description,and the ability to identify abnormal dates.Compared to some state-of-the-art methods,the proposed method achieves an average Spearman delay correlation of 0.847 and a relative distance of 3.477.Furthermore,case analyses are invested in regions of China's Mainland,Europe,and the United States,investigating both the overall and sub-regional network fluctuations.To represent the impact of network fluctuations in sub-regions,a response loss value was developed.The times that are prone to fluctuations are also discussed through the classification of time series data.The research can offer a novel approach to system monitoring,providing a research direction that utilizes individual data combined to represent macroscopic states.Our code will be released at https://github.com/daozhong/STPN.git. 展开更多
关键词 Intelligent transportation system Air traffic network Deviation measurement spatial-temporal path networks Operational monitoring
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Molecular Simulations of Dynamic Heterogeneity of Segment Motion and Bond Exchange in Polymer Vitrimers
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作者 Lang Shuai Jiang-Long Li +4 位作者 Jian-Long Wen Ying-Ying Xu Shui Yu Bo-Yu Ding Yi-Jing Nie 《Chinese Journal of Polymer Science》 2026年第1期242-255,I0017,共15页
Vitrimers belong to a class of polymeric materials capable of bond exchange reactions,showing great promise for environmental protection and sustainable development.However,studies on the coupling mechanism between th... Vitrimers belong to a class of polymeric materials capable of bond exchange reactions,showing great promise for environmental protection and sustainable development.However,studies on the coupling mechanism between the bond exchange kinetics and segmental dynamics near the glass transition temperature(T_(g))remain scarce.Herein,we employed molecular dynamics simulations to investigate the dynamic heterogeneity of the segment motion and bond exchange in vitrimers.The simulation results revealed that the bond exchange energy barrier exerts a much stronger influence on the bond exchange kinetics than on the segmental dynamics.At lower temperatures,slower segmental relaxation further constraind the bond exchange rate.Additionally,increasing the bond exchange energy barrier markedly enhanced the dynamic heterogeneity of segment motion.A close correlation was observed between heterogeneity and bond exchange.This study elucidated the coupling mechanism between bond exchange and segmental dynamics at the molecular scale,thereby providing a theoretical basis for designing vitrimer materials with tunable dynamic properties. 展开更多
关键词 Molecular dynamics simulations Vitrimers dynamic heterogeneity
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Fluid migration in calcite nanopores under salinity gradients:Insights from molecular dynamics
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作者 Yi Chen Yan Zhang +1 位作者 Run-Sheng Han Lei Wang 《Acta Geochimica》 2026年第1期185-203,共19页
The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of i... The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of its influence on fluid migration are of crucial importance.While previous studies have revealed that salinity changes can modulate fluid migration,the underlying mechanisms remain poorly understood.We employ molecular dynamics simulations to elucidate how salinity variations in ore-forming fluids modulate the adsorption onto calcite nanopore walls,thereby revealing the microscopic mechanisms governing ore fluid transport through calcite nano-fractures.The results show that the adsorption energy Eint of the solution on the calcite surface increased from -14,948.84±182.48 kcal/mol to -12,144.08±118.2 kcal/mol as salinity increased,which is conducive to the long-range transport of the fluid in the calcite nanopore. 展开更多
关键词 Fluid transport dynamics Salinity gradient regulation Calcite nanopores Molecular dynamics simulation
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Short-chain Length Dependence of Equilibrium Dynamics and Nonlinear Rheology in Unentangled Long-chain/Short-chain Polymer Blends
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作者 Xiao-Yang Wang Bo Liu +2 位作者 Li-Jia An Zhen-Hua Wang Yu-Yuan Lu 《Chinese Journal of Polymer Science》 2026年第2期525-535,I0016,共12页
The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behav... The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behavior of dispersed long chains.Using molecular dynamics simulations based on the Kremer-Grest model,we systematically explore the N_(S)-dependence of static conformations,equilibrium dynamics,and nonlinear shear responses in unentangled long-chain/short-chain polymer blends.Our results demonstrate a decoupling between the static and dynamic sensitivity to N_(S):while the static chain size,R_g,follows Flory theory with slight swelling at small N_(S) due to incomplete excluded volume screening,the diffusion coefficient,D,and the relaxation time,τ_(0),exhibit a strong,non-monotonic N_(S)-dependence,transitioning from monomeric friction dominance at small N_(S) to collective segmental rearrangement at large N_(S).Additionally,we observe partial decoupling between the viscous and normal stress responses:while the zero-shear viscosity,η,is strongly N_(S)-dependent,the first and second normal stress coefficients,Ψ_(1) and Ψ_(2),collapse onto universal curves when scaled by the dimensionless shear rate,γτ_(0),suggesting a common mechanism of orientation and stretching.Under shear,long chains compress in the vorticity direction λ_(z)~Wi^(-0.2),which reduces collision frequency and contributes to shear thinning,while the scaling of weaker orientation resistance m_(G)~Wi^(0.35)reflects hydrodynamic screening by the short-chain matrix.These findings highlight the limitations of single-chain models and emphasize the necessity of considering N_(S)-dependent matrix dynamics and flow-induced structural changes in understanding the rheology of unentangled polymer blends. 展开更多
关键词 Unentangled polymer blend Nonlinear rheology Equilibrium dynamics Hydrodynamic interaction screening Molecular dynamics simulation
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MDGET-MER:Multi-Level Dynamic Gating and Emotion Transfer for Multi-Modal Emotion Recognition
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作者 Musheng Chen Qiang Wen +2 位作者 Xiaohong Qiu Junhua Wu Wenqing Fu 《Computers, Materials & Continua》 2026年第3期872-893,共22页
In multi-modal emotion recognition,excessive reliance on historical context often impedes the detection of emotional shifts,while modality heterogeneity and unimodal noise limit recognition performance.Existing method... In multi-modal emotion recognition,excessive reliance on historical context often impedes the detection of emotional shifts,while modality heterogeneity and unimodal noise limit recognition performance.Existing methods struggle to dynamically adjust cross-modal complementary strength to optimize fusion quality and lack effective mechanisms to model the dynamic evolution of emotions.To address these issues,we propose a multi-level dynamic gating and emotion transfer framework for multi-modal emotion recognition.A dynamic gating mechanism is applied across unimodal encoding,cross-modal alignment,and emotion transfer modeling,substantially improving noise robustness and feature alignment.First,we construct a unimodal encoder based on gated recurrent units and feature-selection gating to suppress intra-modal noise and enhance contextual representation.Second,we design a gated-attention crossmodal encoder that dynamically calibrates the complementary contributions of visual and audio modalities to the dominant textual features and eliminates redundant information.Finally,we introduce a gated enhanced emotion transfer module that explicitly models the temporal dependence of emotional evolution in dialogues via transfer gating and optimizes continuity modeling with a comparative learning loss.Experimental results demonstrate that the proposed method outperforms state-of-the-art models on the public MELD and IEMOCAP datasets. 展开更多
关键词 Multi-modal emotion recognition dynamic gating emotion transfer module cross-modal dynamic alignment noise robustness
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SSA*-PDWA:A Hierarchical Path Planning Framework with Enhanced A*Algorithm and Dynamic Window Approach for Mobile Robots
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作者 Lishu Qin Yu Gao Xinyuan Lu 《Computers, Materials & Continua》 2026年第4期2069-2094,共26页
With the rapid development of intelligent navigation technology,efficient and safe path planning for mobile robots has become a core requirement.To address the challenges of complex dynamic environments,this paper pro... With the rapid development of intelligent navigation technology,efficient and safe path planning for mobile robots has become a core requirement.To address the challenges of complex dynamic environments,this paper proposes an intelligent path planning framework based on grid map modeling.First,an improved Safe and Smooth A*(SSA*)algorithm is employed for global path planning.By incorporating obstacle expansion and cornerpoint optimization,the proposed SSA*enhances the safety and smoothness of the planned path.Then,a Partitioned Dynamic Window Approach(PDWA)is integrated for local planning,which is triggered when dynamic or sudden static obstacles appear,enabling real-time obstacle avoidance and path adjustment.A unified objective function is constructed,considering path length,safety,and smoothness comprehensively.Multiple simulation experiments are conducted on typical port grid maps.The results demonstrate that the improved SSA*significantly reduces the number of expanded nodes and computation time in static environmentswhile generating smoother and safer paths.Meanwhile,the PDWA exhibits strong real-time performance and robustness in dynamic scenarios,achieving shorter paths and lower planning times compared to other graph search algorithms.The proposedmethodmaintains stable performance across maps of different scales and various port scenarios,verifying its practicality and potential for wider application. 展开更多
关键词 dynamic window approach improved A*algorithm dynamic path planning trajectory optimization
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Dynamic behavior of steel post/wood panel railway noise barriers under aerodynamic loads induced by high-speed trains
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作者 Dongyun Liu Chao Wang +3 位作者 Jaime Gonzalez-Libreros Andréas Andersson Lennart Elfgren Gabriel Sas 《Railway Engineering Science》 2026年第1期55-84,共30页
Railway noise barriers are an essential piece of infrastructure for reducing noise propagation.However,these barriers experience aerodynamic loads generated by high-speed trains,leading to dynamic effects that may com... Railway noise barriers are an essential piece of infrastructure for reducing noise propagation.However,these barriers experience aerodynamic loads generated by high-speed trains,leading to dynamic effects that may compromise their fatigue capacity.The most common structural design for railway noise barriers consists of vertical configurations of posts and panels.However,there have been few dynamic analyses of steel post/wood panel noise barriers under train-induced aerodynamic loads.This study used dynamic finite element analysis to assess the dynamic behavior of such noise barriers.Analysis of a 40-m-long noise barrier model and a triangular simplified load model,the latter of which effectively represented the detailed aerodynamic load,were first used to establish the model and input of the moving load during dynamic simulation.Then,the effects of different parameters on the dynamic response of the noise barrier were evaluated,including the damping ratio,the profile of the steel post,the span length of the panel,the barrier height,and the train speed.Gray relational analysis indicated that barrier height exhibited the highest correlations with the dynamic responses,followed by train speed,post profile,span length,and damping ratio.A reduction in the natural frequency and an increase in the train speed result in a higher peak response and more pronounced fluctuations between the nose and tail waves.The dynamic amplification factor(DAF)was found to be related to both the natural frequency and train speed.A model was proposed showing that the DAF significantly increases as the square of the natural frequency decreases and the cube of the train speed rises. 展开更多
关键词 Aerodynamic load dynamic amplification factor dynamic behavior Finite element analysis High-speed train Railway noise barrier
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Dynamic Behaviors of Localized Waves of the(2+1)-Dimensional Yu-Toda-Sasa-Fukuyama Equation
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作者 SUN Xiaoqing XIA Yarong +1 位作者 YAO Ruoxia WANG Weiqing 《应用数学》 北大核心 2026年第2期624-638,共15页
In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equ... In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equation,but also analyze the dynamical behaviors of nonlinear local wave propagation in shallow water.Firstly,based on the Hirota bilinear approach,one to four-order soliton solutions of the YTSF equation are obtained,and the effects of different parameters on the amplitude,propagation trajectory,and displacement of solitons are investigated.Secondly,using the long wave limit approach,one to three-order lump solutions and various physical quantities of the YTSF equation are derived.It is found that the real and imaginary parts of the parameter pi dominate the propagation trajectory and the shape of lump waves,respectively.Furthermore,we construct the hybrid solution for the YTSF equation,leading to the conclusion that the interaction between lumps and solitons constitutes an elastic collision.To intuitively understand the dynamic behaviors of these solutions,we conduct numerical simulations to present vivid three-dimensional visualizations. 展开更多
关键词 (2+1)-dimensional Yu-Toda-Sasa-Fukuyama equation Hirota bilinear approach Lump solutions dynamic behaviors
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A Joint Optimization Model for Device Selection and Power Allocation under Dynamic Uncertain Environments
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作者 Bohui Li Bin Wang +2 位作者 Linjie Wu Xingjuan Cai Maoqing Zhang 《Computers, Materials & Continua》 2026年第2期1059-1086,共28页
Federated Learning(FL)provides an effective framework for efficient processing in vehicular edge computing.However,the dynamic and uncertain communication environment,along with the performance variations of vehicular... Federated Learning(FL)provides an effective framework for efficient processing in vehicular edge computing.However,the dynamic and uncertain communication environment,along with the performance variations of vehicular devices,affect the distribution and uploading processes of model parameters.In FL-assisted Internet of Vehicles(IoV)scenarios,challenges such as data heterogeneity,limited device resources,and unstable communication environments become increasingly prominent.These issues necessitate intelligent vehicle selection schemes to enhance training efficiency.Given this context,we propose a new scenario involving FL-assisted IoV systems under dynamic and uncertain communication conditions,and develop a dynamic interval multi-objective optimization algorithm to jointly optimize various factors including training experiments,system energy consumption,and bandwidth utilization to meet multi-criteria resource optimization requirements.For the problem at hand,we design a dynamic interval multi-objective optimization algorithm based on interval overlap detection.Simulation results demonstrate that our method outperforms other solutions in terms of accuracy,training cost,and server utilization.It effectively enhances training efficiency under wireless channel environments while rationally utilizing bandwidth resources,thus possessing significant scientific value and application potential in the field of IoV. 展开更多
关键词 Internet of vehicles edge computing dynamic uncertain environments device selection power allocation dynamic interval multi-objective algorithm
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Spatio-Temporal Dynamics of the Vegetation Cover in a Northern Forest of Morocco:Izarene Forest
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作者 Fatima-Zahra Elmassamri Said Laaribya 《Research in Ecology》 2026年第1期79-98,共20页
The study presents an analysis of the spatiotemporal evolution of vegetation cover in the Izarene forest,using LANDSAT satellite images collected for the years 1984,2003,and 2022.The methodological approach is based o... The study presents an analysis of the spatiotemporal evolution of vegetation cover in the Izarene forest,using LANDSAT satellite images collected for the years 1984,2003,and 2022.The methodological approach is based on the use of ArcGIS 10.8 software for processing multispectral images,as well as the calculation of the Normalized Difference Vegetation Index(NDVI),which enables the observation of variations in vegetation cover over time.The findings show that biodiversity is pretty abundant,but they also show that some places with low vegetation density are under a lot of stress.Due in large part to overuse of natural resources,uncontrolled human activity,and environmental factors,these regions seem to be more vulnerable to degradation.However,a decrease in deforestation over the past 20 years is revealed by comparing the two periods(1984–2003 and 2003–2022).The participation of governmental agencies,especially the Department of Water and Forests,through concrete projects like reforestation,forest fire prevention,and awareness-raising campaigns among local communities,is responsible for this progress.In several areas,these measures have stabilized or even improved the state of the vegetation.The analysis emphasizes how crucial sustainable,integrated,and participatory management is to protecting the Izarene forest,which is a significant resource for maintaining the region’s ecological balance. 展开更多
关键词 FOREST Izarene Vegetation Cover dynamicS DEGRADATION Morocco
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