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Multi-scale variations and future projections of dry-wet conditions over the monsoon transitional zone in East Asia:A review
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作者 Wen Chen Jinling Piao +4 位作者 Shangfeng Chen Lin Wang Wei Zhao Zhikai Wang Qiulin Wang 《Fundamental Research》 2025年第4期1597-1606,共10页
The East Asian monsoon transitional zone(MTZ)is a northeast-southwest oriented belt between the wet monsoon areas and the northwestern dry areas of China with a fragile ecology and high climate sensitivity.The climate... The East Asian monsoon transitional zone(MTZ)is a northeast-southwest oriented belt between the wet monsoon areas and the northwestern dry areas of China with a fragile ecology and high climate sensitivity.The climate in the MTZ is characterized by strong instability and large variability,resulting in frequent occurrence of extreme weather and climate events.A number of studies have focused on the dry-wet characteristics from different perspectives,taking into account the increasing problems of water scarcity and ecological risks.This study reviews the multi-scale variations,underlying mechanisms and future projections of dry-wet conditions over the MTZ under global warming.The main findings over the last few decades are summarized as follows:1)the interannual variability of summer precipitation is under the combined impacts of oceanic forcings and internal atmospheric teleconnection patterns at mid-high latitudes;2)an interdecadal decrease in summer precipitation amount in the MTZ was observed in the late 1990s due to a Silk-Road pattern-like wave train triggered by the combined impacts of the Atlantic Multidecadal Oscillation-like SST warming over the North Atlantic and positive-to-negative phase shift of the Pacific Decadal Oscillation(PDO);3)a pronounced drying trend has been observed during 1951-2005,which is mainly attributed to human activities and internal atmospheric variability,including increased aerosols,land-use changes,thermal forcing over the Tibetan Plateau,and the phase shift of the PDO;and 4)the summer precipitation in the MTZ is projected to increase under global warming with considerable uncertainties mainly due to internal atmospheric variability,including the Arctic Oscillation and the Polar-Eurasian pattern.This review attempts to provide a clear and systematic picture on the distinctive changing features of dry-wet conditions over the MTZ,and to attract the interest of the scientific community in climate change over this unique“transition”domain. 展开更多
关键词 East Asian monsoon transitional zone multi-scale variations Future projection Atmospheric teleconnection pattern Atlantic multidecadal oscillation Pacific decadal oscillation Internal atmospheric variability Global warming
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Multi-scale temperature variations and their regional differences in China during the Medieval Climate Anomaly 被引量:1
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作者 HAO Zhixin WU Maowei +2 位作者 LIU Yang ZHANG Xuezhen ZHENG Jingyun 《Journal of Geographical Sciences》 SCIE CSCD 2020年第1期119-130,共12页
The Medieval Climate Anomaly(MCA,AD950-1250)is the most recent warm period lasting for several hundred years and is regarded as a reference scenario when studying the impact of and adaptation to global and regional wa... The Medieval Climate Anomaly(MCA,AD950-1250)is the most recent warm period lasting for several hundred years and is regarded as a reference scenario when studying the impact of and adaptation to global and regional warming.In this study,we investigated the characteristics of temperature variations on decadal-centennial scales during the MCA for four regions(Northeast,Northwest,Central-east,and Tibetan Plateau)in China,based on high-resolution temperature reconstructions and related warm-cold records from historical documents.The ensemble empirical mode decomposition method is used to analyze the time series.The results showed that for China as a whole,the longest warm period during the last 2000 years occurred in the 10th-13th centuries,although there were multi-decadal cold intervals in the middle to late 12th century.However,in the beginning and ending decades,warm peaks and phases on the decadal scale of the MCA for different regions were not consistent with each other.On the inter-decadal scale,regional temperature variations were similar from 950 to 1130;moreover,their amplitudes became smaller,and the phases did not agree well from 1130 to 1250.On the multi-decadal to centennial scale,all four regions began to warm in the early 10th century and experienced two cold intervals during the MCA.However,the Northwest and Central-east China were in step with each other while the warm periods in the Northeast China and Tibetan Plateau ended about 40-50 years earlier.On the multi-centennial scale,the mean temperature difference between the MCA and Little Ice Age was significant in Northeast and Central-east China but not in the Northwest China and Tibetan Plateau.Compared to the mean temperature of the 20th century,a comparable warmth in the MCA was found in the Central-east China,but there was a little cooling in Northeast China;meanwhile,there were significantly lower temperatures in Northwest China and Tibetan Plateau. 展开更多
关键词 China multi-scale variations TEMPERATURE Medieval Climate Anomaly
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Microstructure Analysis of TC4/Al 6063/Al 7075 Explosive Welded Composite Plate via Multi-scale Simulation and Experiment 被引量:1
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作者 Zhou Jianan Luo Ning +3 位作者 Liang Hanliang Chen Jinhua Liu Zhibing Zhou Xiaohong 《稀有金属材料与工程》 北大核心 2025年第1期27-38,共12页
Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer ... Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer composite plate by explosive welding.The microscopic properties of each bonding interface were elucidated through field emission scanning electron microscope and electron backscattered diffraction(EBSD).A methodology combining finite element method-smoothed particle hydrodynamics(FEM-SPH)and molecular dynamics(MD)was proposed for the analysis of the forming and evolution characteristics of explosive welding interfaces at multi-scale.The results demonstrate that the bonding interface morphologies of TC4/Al 6063 and Al 6063/Al 7075 exhibit a flat and wavy configuration,without discernible defects or cracks.The phenomenon of grain refinement is observed in the vicinity of the two bonding interfaces.Furthermore,the degree of plastic deformation of TC4 and Al 7075 is more pronounced than that of Al 6063 in the intermediate layer.The interface morphology characteristics obtained by FEM-SPH simulation exhibit a high degree of similarity to the experimental results.MD simulations reveal that the diffusion of interfacial elements predominantly occurs during the unloading phase,and the simulated thickness of interfacial diffusion aligns well with experimental outcomes.The introduction of intermediate layer in the explosive welding process can effectively produce high-quality titanium/aluminum alloy composite plates.Furthermore,this approach offers a multi-scale simulation strategy for the study of explosive welding bonding interfaces. 展开更多
关键词 TC4/Al 6063/Al 7075 composite plate explosive welding microstructure analysis multi-scale simulation
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A multi-scale and multi-mechanism coupled model for carbon isotope fractionation of methane during shale gas production 被引量:1
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作者 Jun Wang Fang-Wen Chen +4 位作者 Wen-Biao Li Shuang-Fang Lu Sheng-Xian Zhao Yong-Yang Liu Zi-Yi Wang 《Petroleum Science》 2025年第7期2719-2746,共28页
Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some sho... Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies. 展开更多
关键词 Shale gas Isotope fractionation multi-scale Production prediction Adsorbed/free gas ratio
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Epigenetic variation in maize agronomical traits for breeding and trait improvement Author links open overlay panel 被引量:1
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作者 Daolei Zhang Yujun Gan +1 位作者 Liang Le Li Pu 《Journal of Genetics and Genomics》 2025年第3期307-318,共12页
Epigenetics-mediated breeding(epibreeding)involves engineering crop traits and stress responses through the targeted manipulation of key epigenetic features to enhance agricultural productivity.While conventional bree... Epigenetics-mediated breeding(epibreeding)involves engineering crop traits and stress responses through the targeted manipulation of key epigenetic features to enhance agricultural productivity.While conventional breeding methods raise concerns about reduced genetic diversity,epibreeding propels crop improvement through epigenetic variations that regulate gene expression,ultimately impacting crop yield.Epigenetic regulation in crops encompasses various modes,including histone modification,DNA modification,RNA modification,non-coding RNA,and chromatin remodeling.This review summarizes the epigenetic mechanisms underlying major agronomic traits in maize and identifies candidate epigenetic landmarks in the maize breeding process.We propose a valuable strategy for improving maize yield through epibreeding,combining CRISPR/Cas-based epigenome editing technology and Synthetic Epigenetics(SynEpi).Finally,we discuss the challenges and opportunities associated with maize trait improvement through epibreeding. 展开更多
关键词 Epibreeding Epigenetic variation Agronomical traits Epigenome editing Synthetic epigenetics
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A Robust GNSS Navigation Filter Based on Maximum Correntropy Criterion with Variational Bayesian for Adaptivity 被引量:1
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作者 Dah-Jing Jwo Yi Chang Ta-Shun Cho 《Computer Modeling in Engineering & Sciences》 2025年第3期2771-2789,共19页
In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenario... In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenarios with non-Gaussian noise and heavy-tailed outliers.The proposed design modifies the extended Kalman filter(EKF)for the global navigation satellite system(GNSS),integrating the maximum correntropy criterion(MCC)and the variational Bayesian(VB)method.This adaptive algorithm effectively reduces non-line-of-sight(NLOS)reception contamination and improves estimation accuracy,particularly in time-varying GNSS measurements.Experimental results show that the proposed method significantly outperforms conventional approaches in estimation accuracy under heavy-tailed outliers and non-Gaussian noise.By combining MCC with VB approximation for real-time noise covariance estimation using fixed-point iteration,the VBMCEKF achieves superior filtering performance in challenging GNSS conditions.The method’s adaptability and precision make it ideal for improving satellite navigation performance in stochastic environments. 展开更多
关键词 Maximum correntropy criterion variational Bayesian extended Kalman filter GNSS
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Occluded Gait Emotion Recognition Based on Multi-Scale Suppression Graph Convolutional Network
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作者 Yuxiang Zou Ning He +2 位作者 Jiwu Sun Xunrui Huang Wenhua Wang 《Computers, Materials & Continua》 SCIE EI 2025年第1期1255-1276,共22页
In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accurac... In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accuracy significantly declines when the data is occluded.To enhance the accuracy of gait emotion recognition under occlusion,this paper proposes a Multi-scale Suppression Graph ConvolutionalNetwork(MS-GCN).TheMS-GCN consists of three main components:Joint Interpolation Module(JI Moudle),Multi-scale Temporal Convolution Network(MS-TCN),and Suppression Graph Convolutional Network(SGCN).The JI Module completes the spatially occluded skeletal joints using the(K-Nearest Neighbors)KNN interpolation method.The MS-TCN employs convolutional kernels of various sizes to comprehensively capture the emotional information embedded in the gait,compensating for the temporal occlusion of gait information.The SGCN extracts more non-prominent human gait features by suppressing the extraction of key body part features,thereby reducing the negative impact of occlusion on emotion recognition results.The proposed method is evaluated on two comprehensive datasets:Emotion-Gait,containing 4227 real gaits from sources like BML,ICT-Pollick,and ELMD,and 1000 synthetic gaits generated using STEP-Gen technology,and ELMB,consisting of 3924 gaits,with 1835 labeled with emotions such as“Happy,”“Sad,”“Angry,”and“Neutral.”On the standard datasets Emotion-Gait and ELMB,the proposed method achieved accuracies of 0.900 and 0.896,respectively,attaining performance comparable to other state-ofthe-artmethods.Furthermore,on occlusion datasets,the proposedmethod significantly mitigates the performance degradation caused by occlusion compared to other methods,the accuracy is significantly higher than that of other methods. 展开更多
关键词 KNN interpolation multi-scale temporal convolution suppression graph convolutional network gait emotion recognition human skeleton
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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 Adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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BDMFuse:Multi-scale network fusion for infrared and visible images based on base and detail features
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作者 SI Hai-Ping ZHAO Wen-Rui +4 位作者 LI Ting-Ting LI Fei-Tao Fernando Bacao SUN Chang-Xia LI Yan-Ling 《红外与毫米波学报》 北大核心 2025年第2期289-298,共10页
The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method f... The fusion of infrared and visible images should emphasize the salient targets in the infrared image while preserving the textural details of the visible images.To meet these requirements,an autoencoder-based method for infrared and visible image fusion is proposed.The encoder designed according to the optimization objective consists of a base encoder and a detail encoder,which is used to extract low-frequency and high-frequency information from the image.This extraction may lead to some information not being captured,so a compensation encoder is proposed to supplement the missing information.Multi-scale decomposition is also employed to extract image features more comprehensively.The decoder combines low-frequency,high-frequency and supplementary information to obtain multi-scale features.Subsequently,the attention strategy and fusion module are introduced to perform multi-scale fusion for image reconstruction.Experimental results on three datasets show that the fused images generated by this network effectively retain salient targets while being more consistent with human visual perception. 展开更多
关键词 infrared image visible image image fusion encoder-decoder multi-scale features
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Role of variation coefficient of stone density in determining success of shock wave lithotripsy in urinary calculi 被引量:1
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作者 Nadeem Iqbal Aisha Hasan +2 位作者 Sajid Iqbal Sadaf Noureen Saeed Akhter 《World Journal of Nephrology》 2025年第1期110-118,共9页
BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free r... BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes. 展开更多
关键词 Computed tomography Shock wave lithotripsy Stone heterogeneity variation coefficient of stone density Kidney stones
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A Nonlinear Multi-Scale Interaction Model for Atmospheric Blocking:A Tool for Exploring the Impact of Changing Climate on Mid-to-High Latitude Weather Extremes 被引量:1
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作者 Dehai LUO Wenqi ZHANG Binhe LUO 《Advances in Atmospheric Sciences》 2025年第10期2018-2035,共18页
A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and... A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread. 展开更多
关键词 nonlinear Schrödinger equation nonlinear multi-scale interaction model of atmospheric blocking meridional background potential vorticity gradient climate change mid-to-high latitude weather extremes
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The Minimal Affine Total Variation in Minkowski Spaces
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作者 MOU Shuang 《数学进展》 北大核心 2025年第1期164-176,共13页
In this paper,we use the solution of the even functional Minkowski problem to show that there is a minimizing affine Minkowski total variation of the function of bounded variation.Moreover,for the Minkowski total vari... In this paper,we use the solution of the even functional Minkowski problem to show that there is a minimizing affine Minkowski total variation of the function of bounded variation.Moreover,for the Minkowski total variation,we use the method of convexation to establish the same conclusion as the convex body space. 展开更多
关键词 convex body minimal surface area Minkowski space bounded variation
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Convergence of a New Bregman Projection Method with a Self-adaptive Stepsize for Solving Monotone Inclusion Problems and Variational Inequality Problems in Reflexive Banach Spaces
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作者 CHEN Lulu CAI Gang 《数学进展》 北大核心 2025年第1期141-163,共23页
The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.... The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms. 展开更多
关键词 Bregman distance variational inequality monotone inclusion maximal operator reflexive Banach space
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A Review on Modeling Environmental Loading Effects and Their Contributions to Nonlinear Variations of Global Navigation Satellite System Coordinate Time Series 被引量:1
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作者 Zhao Li Weiping Jiang +3 位作者 Tonie van Dam Xiaowei Zou Qusen Chen Hua Chen 《Engineering》 2025年第4期26-37,共12页
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at... Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050. 展开更多
关键词 Environmental loading Global navigation satellite system Nonlinear variations Time series analysis Surface mass distribution Green’s function Spherical harmonic function
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The Role of Multi-scale Integrated Hierarchical Intervention in Preventing Psychological Crises among College Students
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作者 XIONG Jun ZHAO Xiaoqing +3 位作者 SHUAI Yixin FENG Yuqi ZHUGE Junzhe LUO Jiaming 《贵州大学学报(自然科学版)》 2025年第4期18-25,共8页
Mental health problems and potential psychological crises affect the healthy growth and learning performance of college students.Effective and suitable prevention of psychological crises among college students is a co... Mental health problems and potential psychological crises affect the healthy growth and learning performance of college students.Effective and suitable prevention of psychological crises among college students is a continuous challenge university managers face.To explore a method of preventing psychological crises among college students,we measured 38661 students by using SCL-90(symptom check list-90)and screened out 5790 students with positive results.Then,we measured 33188 students by using PHQ-9(patient health questionnaire-9)and screened out 603 students with suicidal ideation or behavior;we interviewed 392 students by using GAQ(growth adversity questionnaire).The number of students who had positive results at both phases is 155.As a result,we obtained a data set(N=76)by integrating the students who tested positive on the PHQ-9(i.e.total score≥20)with those who completed the PHQ-9 and GAQ.In addition,we obtained a data set(N=50)by excluding the cases in which the GAQ score is 0.With regard to QCA(qualitative comparative analysis)results,the data set(N=76)exhibits 5 constellations of solutions with a coverage rate greater than 0.7,and the first eight indicators of the PHQ-9 constitute the explanatory variables in the combined solutions.About the data set(N=50),the combined solutions are extremely complicated and the explanatory variables encompass indicators from both the PHQ-9 and GAQ.All these mean that the multi-scale could more comprehensively reflect mental health states of college students,thus enhance the accuracy and effectiveness of the corresponding hierarchical intervention,and finally provide support for preventing psychological crises in universities. 展开更多
关键词 multi-scale hierarchical intervention preventing psychological crises
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Multi-scale modeling of the multi-phase flow in water electrolyzers for green hydrogen production
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作者 Lizhen Wu Qing Wang +2 位作者 Wenzhi Li Mingcong Tang Liang An 《Materials Reports(Energy)》 2025年第3期40-49,共10页
Water electrolyzers play a crucial role in green hydrogen production.However,their efficiency and scalability are often compromised by bubble dynamics across various scales,from nanoscale to macroscale components.This... Water electrolyzers play a crucial role in green hydrogen production.However,their efficiency and scalability are often compromised by bubble dynamics across various scales,from nanoscale to macroscale components.This review explores multi-scale modeling as a tool to visualize multi-phase flow and improve mass transport in water electrolyzers.At the nanoscale,molecular dynamics(MD)simulations reveal how electrode surface features and wettability influence nanobubble nucleation and stability.Moving to the mesoscale,models such as volume of fluid(VOF)and lattice Boltzmann method(LBM)shed light on bubble transport in porous transport layers(PTLs).These insights inform innovative designs,including gradient porosity and hydrophilic-hydrophobic patterning,aimed at minimizing gas saturation.At the macroscale,VOF simulations elucidate two-phase flow regimes within channels,showing how flow field geometry and wettability affect bubble discharging.Moreover,artificial intelligence(AI)-driven surrogate models expedite the optimization process,allowing for rapid exploration of structural parameters in channel-rib flow fields and porous flow field designs.By integrating these approaches,we can bridge theoretical insights with experimental validation,ultimately enhancing water electrolyzer performance,reducing costs,and advancing affordable,high-efficiency hydrogen production. 展开更多
关键词 Water electrolyzers Bubble dynamics multi-scale MULTI-PHASE MODELING
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Multi-Scale Feature Fusion Network for Accurate Detection of Cervical Abnormal Cells
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作者 Chuanyun Xu Die Hu +3 位作者 Yang Zhang Shuaiye Huang Yisha Sun Gang Li 《Computers, Materials & Continua》 2025年第4期559-574,共16页
Detecting abnormal cervical cells is crucial for early identification and timely treatment of cervical cancer.However,this task is challenging due to the morphological similarities between abnormal and normal cells an... Detecting abnormal cervical cells is crucial for early identification and timely treatment of cervical cancer.However,this task is challenging due to the morphological similarities between abnormal and normal cells and the significant variations in cell size.Pathologists often refer to surrounding cells to identify abnormalities.To emulate this slide examination behavior,this study proposes a Multi-Scale Feature Fusion Network(MSFF-Net)for detecting cervical abnormal cells.MSFF-Net employs a Cross-Scale Pooling Model(CSPM)to effectively capture diverse features and contextual information,ranging from local details to the overall structure.Additionally,a Multi-Scale Fusion Attention(MSFA)module is introduced to mitigate the impact of cell size variations by adaptively fusing local and global information at different scales.To handle the complex environment of cervical cell images,such as cell adhesion and overlapping,the Inner-CIoU loss function is utilized to more precisely measure the overlap between bounding boxes,thereby improving detection accuracy in such scenarios.Experimental results on the Comparison detector dataset demonstrate that MSFF-Net achieves a mean average precision(mAP)of 63.2%,outperforming state-of-the-art methods while maintaining a relatively small number of parameters(26.8 M).This study highlights the effectiveness of multi-scale feature fusion in enhancing the detection of cervical abnormal cells,contributing to more accurate and efficient cervical cancer screening. 展开更多
关键词 Cervical abnormal cells image detection multi-scale feature fusion contextual information
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Using multi-scale interaction mechanisms in yolk-shell structured C/Co composite materials for electromagnetic wave absorption
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作者 Jintang Zhou Kexin Zou +11 位作者 Jiaqi Tao Jun Liu Yijie Liu Lvtong Duan Zhenyu Cheng Borui Zha Zhengjun Yao Guiyu Peng Xuewei Tao Hexia Huang Yao Ma Peijiang Liu 《Journal of Materials Science & Technology》 2025年第12期36-44,共9页
Advanced chemical engineering for simultaneous modulation of nanomaterial morphology, defects, interfaces, and structure to enhance electromagnetic and microwave absorption (MA) performance. However, accurately distin... Advanced chemical engineering for simultaneous modulation of nanomaterial morphology, defects, interfaces, and structure to enhance electromagnetic and microwave absorption (MA) performance. However, accurately distinguishing the MA contributions of different scale factors and tuning the optimal combined effects remains a formidable challenge. This study employs a synergistic approach combining template protection etching and vacuum annealing to construct a controlled system of micrometer-sized cavities and amorphous carbon matrices in metal-organic framework (MOF) derivatives. The results demonstrate that the spatial effects introduced by the hollow structure enhance dielectric loss but significantly weaken impedance matching. By increasing the proportion of amorphous carbon, the balance between electromagnetic loss and impedance matching can be effectively maintained. Importantly, in a suitable graphitization environment, the presence of oxygen vacancies in amorphous carbon can induce significant polarization to compensate for the reduced conductivity loss due to the absence of sp2 carbon. Through the synergistic effects of morphology and composition, the samples exhibit a broader absorption bandwidth (6.28 GHz) and stronger reflection loss (−61.64 dB) compared to the original MOF. In conclusion, this study aims to elucidate the multiscale impacts of macroscopic micro-nano structure and microscopic defect engineering, providing valuable insights for future research in this field. 展开更多
关键词 MOFS multi-scale regulation Yolk-shell structure Amorphous carbon Oxygen vacancy Microwave absorption
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Fake News Detection Based on Cross-Modal Ambiguity Computation and Multi-Scale Feature Fusion
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作者 Jianxiang Cao Jinyang Wu +5 位作者 Wenqian Shang Chunhua Wang Kang Song Tong Yi Jiajun Cai Haibin Zhu 《Computers, Materials & Continua》 2025年第5期2659-2675,共17页
With the rapid growth of socialmedia,the spread of fake news has become a growing problem,misleading the public and causing significant harm.As social media content is often composed of both images and text,the use of... With the rapid growth of socialmedia,the spread of fake news has become a growing problem,misleading the public and causing significant harm.As social media content is often composed of both images and text,the use of multimodal approaches for fake news detection has gained significant attention.To solve the problems existing in previous multi-modal fake news detection algorithms,such as insufficient feature extraction and insufficient use of semantic relations between modes,this paper proposes the MFFFND-Co(Multimodal Feature Fusion Fake News Detection with Co-Attention Block)model.First,the model deeply explores the textual content,image content,and frequency domain features.Then,it employs a Co-Attention mechanism for cross-modal fusion.Additionally,a semantic consistency detectionmodule is designed to quantify semantic deviations,thereby enhancing the performance of fake news detection.Experimentally verified on two commonly used datasets,Twitter and Weibo,the model achieved F1 scores of 90.0% and 94.0%,respectively,significantly outperforming the pre-modified MFFFND(Multimodal Feature Fusion Fake News Detection with Attention Block)model and surpassing other baseline models.This improves the accuracy of detecting fake information in artificial intelligence detection and engineering software detection. 展开更多
关键词 Fake news detection MULTIMODAL cross-modal ambiguity computation multi-scale feature fusion
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MA-VoxelMorph:Multi-scale attention-based VoxelMorph for nonrigid registration of thoracoabdominal CT images
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作者 Qing Huang Lei Ren +3 位作者 Tingwei Quan Minglei Yang Hongmei Yuan Kai Cao 《Journal of Innovative Optical Health Sciences》 2025年第1期135-151,共17页
This paper aims to develop a nonrigid registration method of preoperative and intraoperative thoracoabdominal CT images in computer-assisted interventional surgeries for accurate tumor localization and tissue visualiz... This paper aims to develop a nonrigid registration method of preoperative and intraoperative thoracoabdominal CT images in computer-assisted interventional surgeries for accurate tumor localization and tissue visualization enhancement.However,fine structure registration of complex thoracoabdominal organs and large deformation registration caused by respiratory motion is challenging.To deal with this problem,we propose a 3D multi-scale attention VoxelMorph(MAVoxelMorph)registration network.To alleviate the large deformation problem,a multi-scale axial attention mechanism is utilized by using a residual dilated pyramid pooling for multi-scale feature extraction,and position-aware axial attention for long-distance dependencies between pixels capture.To further improve the large deformation and fine structure registration results,a multi-scale context channel attention mechanism is employed utilizing content information via adjacent encoding layers.Our method was evaluated on four public lung datasets(DIR-Lab dataset,Creatis dataset,Learn2Reg dataset,OASIS dataset)and a local dataset.Results proved that the proposed method achieved better registration performance than current state-of-the-art methods,especially in handling the registration of large deformations and fine structures.It also proved to be fast in 3D image registration,using about 1.5 s,and faster than most methods.Qualitative and quantitative assessments proved that the proposed MA-VoxelMorph has the potential to realize precise and fast tumor localization in clinical interventional surgeries. 展开更多
关键词 Thoracoabdominal CT image registration large deformation fine structure multi-scale attention mechanism
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