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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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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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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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Comparative analysis of windbreak configurations for unloaded gondola train cars under crosswinds based on computational fluid dynamics and multi-body dynamics
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作者 Jiayuan SONG Wentao HE +1 位作者 Yanlin HU Kaiyun WANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2026年第1期26-42,共17页
Understanding the aerodynamic and dynamic characteristics of unloaded freight trains in crosswinds is pivotal for ensuring their operational safety and reliability.The dynamic performance of unloaded gondola cars unde... Understanding the aerodynamic and dynamic characteristics of unloaded freight trains in crosswinds is pivotal for ensuring their operational safety and reliability.The dynamic performance of unloaded gondola cars under varying windbreak heights is therefore investigated in this study,revealing distinct differences in lateral stability and safety indicators,and enabling the determination of an optimal windbreak height.A 3D unsteady aerodynamic model was developed using the improved delayed detached eddy simulation(IDDES)method and an overset numerical mesh.Also leveraging a multi-body dynamics(MBD)model of a three-wagon freight car configuration,we investigate time-averaged aerodynamic forces,transient flow field distributions,and nonlinear dynamic responses.Parametric analyses reveal a non-monotonic relationship between the height of the windbreak and the stability of the train.A windbreak with a critical height of 2 m(0.74 relative to the car body height)results in 76%,64%,and 81%lower values of the derailment coefficient CD,wheel unloading ratio R,and overturning coefficient C_(O),respectively.Notably,when the height of the windbreak exceeds 2 m,vortices within the gondola induce an adverse pressure coefficient distribution(C_(p)=−2.17)on the leeward internal wall,intensifying the lateral force and overturning moment.Furthermore,frequency-domain analysis reveals that the lateral sway and overturning vibration mode are associated with low-frequency(1.61 Hz)lateral vibrations under crosswind conditions.This study provides a theoretical foundation for the design and optimization of railway windbreaks. 展开更多
关键词 CROSSWIND Train gondola Unsteady aerodynamics dynamic response Train safety WINDBREAKS
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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 track(rack)-bridge system under running vehicle and temperature load in rack railway
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作者 Zhihui Chen Lang Wang +2 位作者 Zhixian Chen Zhaowei Chen Jizhong Yang 《Chinese Journal of Mechanical Engineering》 2026年第1期526-536,共11页
Significant diurnal temperature variations in mountainous rack railways cause stiffness mismatches between the rack structure and simply supported bridges,leading to critical failures like bolt loosening and rack frac... Significant diurnal temperature variations in mountainous rack railways cause stiffness mismatches between the rack structure and simply supported bridges,leading to critical failures like bolt loosening and rack fractures.This study develops a dynamic model of the vehicle-rack-bridge system based on train-track-bridge interaction theory,integrating gear-rack meshing and wheel-rail contact mechanisms.The model analyzes the dynamic response of bridges with varying spans under combined thermal and dynamic loading.Numerical simulations,conducted using finite element analysis,reveal peak vibration accelerations of 1.3 m/s^(2)for the rack,3.0 m/s^(2)for the rail,1.2 m/s^(2)for the sleeper,and 0.1 m/s^(2)for the bridge,with maximum stresses of 3 MPa in the rack,8 MPa in the rail,and 25 MPa in connecting bolts.The results show significant span-dependent amplification of stress and strain in the rack system under thermo-mechanical loading,exceeding material strength limits at 60-meter spans.An innovative elastic connection method is proposed to mitigate stress concentrations effectively,en-hancing system durability.This study introduces a novel approach to modeling complex thermo-mechanical interactions in rack railway systems,validated through extensive simulations,and provides a practical solution for improving structural resilience,offering theoretical guidance for optimizing rack-bridge system design to ensure operational safety in extreme environmental conditions. 展开更多
关键词 Simply supported bridge Rack railway Bridge-track interaction Temperature loads dynamic Mechanical
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Quantitative correlation between stress variation and charge signals of loaded coal and its implication for dynamic fracturing of surrounding rock
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作者 Jinguo Lyu Zhanpeng Xue +3 位作者 Yishan Pan Lianpeng Dai Zhi Tang Xuebin Wang 《International Journal of Mining Science and Technology》 2026年第2期313-331,共19页
To address the key scientific challenge of monitoring the dynamic fracturing of surrounding rock in deep roadways,this study systematically investigates the quantitative relationship between stress and charge signals ... To address the key scientific challenge of monitoring the dynamic fracturing of surrounding rock in deep roadways,this study systematically investigates the quantitative relationship between stress and charge signals during coal mass loading.By integrating innovative analytical approaches,introducing quantitative evaluation indices,and developing a charge–stress inversion model,and incorporating underground monitoring practices,significant progress has been achieved in elucidating the correlation between stress variations and charge signals throughout the entire coal mass fracturing process.First,in the field of stress–charge correlation analysis,empirical mode decomposition(EMD)was combined with wavelet coherence analysis for the first time,enabling the removal of slow-varying stress trends while retaining high-frequency fluctuations.This approach allowed for the quantitative characterization of the evolution of coherence between stress variations and charge fluctuations across multiple time scales.Second,coherence skewness and the proportion of high-coherence intervals were innovatively introduced to examine the influence of time scale selection on correlation results.On this basis,a criterion for determining the near-optimal observation scale of charge signals was proposed,providing a quantitative reference for time scale selection in similar signal analyses.Finally,by correlating charge signals with coal damage factors and stress states,a charge-based damage evolution equation was established to achieve effective stress inversion.Combined with in situ monitoring of stress and charge in roadway surrounding rock,this approach revealed the correlation characteristics of stress and charge intensity responses during the dynamic fracturing process.The results indicate,first,that charge signals are not significantly correlated with the absolute stress level of coal but are directly associated with stress variations following coal damage and failure,with the amplitude of charge fluctuations increasing alongside stress fluctuations.Second,coherence between stress and charge signals varies markedly across time scales,with excessively small or large scales leading to distortion,and the scale corresponding to the peak proportion of intervals with coherence>0.8 was identified as the near-optimal observation scale.Third,charge signals can effectively characterize coal damage factors,and the established damage evolution equation can effectively invert stress variation trends.Fourth,in underground roadways,zones of dynamic fracturing in surrounding rock are commonly located in areas where stress concentration overlaps with regions of high charge intensity,further confirming the strong consistency between charge and stress variations.These findings improve the theoretical framework of charge signal responses in loaded coal and provide a scientific basis for precise“stress-charge”monitoring of dynamic disasters,offering practical potential for engineering applications. 展开更多
关键词 CHARGE Stress Coherence coefficient Time scale dynamic fracturing
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Dynamic response of RC columns under off-central explosions:Experimental,theoretical studies and neural network prediction
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作者 Hao Wang Xiangyu Li +2 位作者 Yong Peng Zhandong Tian Fangyun Lu 《Defence Technology(防务技术)》 2026年第2期314-336,共23页
Reinforced concrete(RC)columns are often subjected to off-central explosion due to the uncertainty of blast locations.However,few studies have focused on the dynamic response of RC columns under offcentral explosions.... Reinforced concrete(RC)columns are often subjected to off-central explosion due to the uncertainty of blast locations.However,few studies have focused on the dynamic response of RC columns under offcentral explosions.A field blast experiment was conducted under close-in explosion with varying detonation offset distances(0 m,0.5 m,and 1 m),the overpressure load and dynamic responses of the full-scale RC columns were measured.Compared with the centrally detonated condition,a relative offset distance of 1.67 decreases the maximum and residual deflections of the RC column by 16.8%and 21.4%,respectively,while increasing the maximum and residual support rotations by 24.7%and 17.8%.Based on the experimental results,a theoretical model was proposed that considers the detonation location and charge mass,boundary conditions,axial compression ratio and material properties.The theoretical model exhibited good agreement with the experimental results,with prediction errors below 10%for both maximum and residual deflection.The effects of parameters were analyzed,and it indicated that an increase in offset distance results in decreased maximum and residual deflections but an increased support angle,thereby exacerbating damage.Higher axial load ratio,span-depth ratio,and longitudinal reinforcement ratio reduce both deflections and support angle.Additionally,a rapid method to predict the maximum and residual deflection of RC columns under off-central blast loading was also proposed based on the Generalized Regression Neural Network(GRNN).Eleven features which related to the RC column properties and the blast characteristics were used in the training process of GRNN,and accurate predictions were achieved with prediction errors within 20%.This study fills the gap in predicting the dynamic response of RC columns under off-central explosion,providing valuable references for blast-resistant design. 展开更多
关键词 dynamic responses RC columns Off-central explosions Theoretical model GRNN
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Overcoming Dynamic Connectivity in Internet of Vehicles:A DAG Lattice Blockchain with Reputation-Based Incentive
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作者 Xiaodong Zhang Wenhan Hou +2 位作者 Juanjuan Wang Leixiao Li Pengfei Yue 《Computers, Materials & Continua》 2026年第2期1803-1822,共20页
Blockchain offers a promising solution to the security challenges faced by the Internet of Vehicles(IoV).However,due to the dynamic connectivity of IoV,blockchain based on a single-chain structure or Directed Acyclic ... Blockchain offers a promising solution to the security challenges faced by the Internet of Vehicles(IoV).However,due to the dynamic connectivity of IoV,blockchain based on a single-chain structure or Directed Acyclic Graph(DAG)structure often suffer from performance limitations.The DAG lattice structure is a novel blockchain model in which each node maintains its own account chain,and only the node itself is allowed to update it.This feature makes the DAG lattice structure particularly suitable for addressing the challenges in dynamically connected IoV environment.In this paper,we propose a blockchain architecture based on the DAG lattice structure,specifically designed for dynamically connected IoV.In the proposed system,nodes must obtain authorization from a trusted authority before joining,forming a permissioned blockchain.Each node is assigned an individual account chain,allowing vehicles with limited storage capacity to participate in the blockchain by storing transactions only from nearby vehicles’account chains.Every transmitted message is treated as a transaction and added to the blockchain,enablingmore efficient data transmission in a dynamic network environment.Areputation-based incentivemechanism is introduced to encourage nodes to behave normally.Experimental results demonstrate that the proposed architecture achieves better performance compared with traditional single-chain and DAG-based approaches in terms of average transmission delay and storage cost. 展开更多
关键词 Blockchain Internet of vehicles dynamic connectivity DAG lattice INCENTIVE
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A New Proposal for Scientific Standards:Modified Hilbert Axiomatic Standards and Dynamic Demarcation Criteria
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作者 CUI Weicheng 《Philosophy Study》 2026年第1期30-44,共15页
Defining science and demarcating it from pseudoscience are longstanding core issues in the philosophy of science.Hilbert’s traditional axiomatic standards(consistency,completeness,independence)struggle with modern co... Defining science and demarcating it from pseudoscience are longstanding core issues in the philosophy of science.Hilbert’s traditional axiomatic standards(consistency,completeness,independence)struggle with modern complex systems,while existing demarcation criteria like replicability and Popper’s falsificationism have practical limitations.Analyzing incompatibilities in complex systems,this paper proposes a revised framework:modified Hilbert axiomatic standards(clearly defined concepts,logical consistency,unrefuted axioms)and dynamic demarcation criteria.Abandoning unattainable traditional requirements of completeness and independence,it emphasizes conceptual clarity,openness,and progressiveness,offering an operational,self-consistent basis for judging scientificity. 展开更多
关键词 scientific standards axiomatic system demarcation problem logical consistency dynamic criteria
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Toughening Recycled Waste Rubbers by Dynamic Interactions for Stress Deconcentration
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作者 Hao-Jia Guo Zhou-Liang Wu +1 位作者 Shuang-Quan Liao Ming-Chao Luo 《Chinese Journal of Polymer Science》 2026年第1期234-241,I0017,共9页
Recycling of waste rubber(WR)is crucial for the sustainable development of the rubber industry.The enhancement of interfacial interactions is the main strategy for waste polymer recycling.However,there is a lack of me... Recycling of waste rubber(WR)is crucial for the sustainable development of the rubber industry.The enhancement of interfacial interactions is the main strategy for waste polymer recycling.However,there is a lack of methods for enhancing the interfacial interactions for WR recycling because WR contains abundant inert C―H bonds.Herein,we designed thioctic acid inverse vulcanization copolymers to endow recycled WR with dynamic disulfide interfacial interactions,significantly improving the mechanical properties of recycled WR.These disulfide interfacial interactions among the recycled WR tend to exchange,which dramatically increases the fractocohesive length and prevents stress concentration near the crack tips.When recycled WR is subjected to external stress,the loads are redistributed across a broad region of adjacent regions instead of being concentrated on a limited length scale,which resists crack propagation.This work effectively recycled WR,providing a strategy for solvent-free reaction-derived inverse vulcanization copolymers to improve the toughness of WR recycling. 展开更多
关键词 Waste rubbers RECYCLING Inverse vulcanization copolymers dynamic interactions Stress deconcentration
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Experimental study on dynamic characteristics and microstructure of lacustrine soft clay
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作者 Zhu Haoyang Li Yurun Zhang Jingjuan 《Earthquake Engineering and Engineering Vibration》 2026年第1期55-70,共16页
In this study,the dynamic characteristics and microstructures of lacustrine soft clays were studied.Dynamic character tests were conducted on undisturbed,remolded,and saturated lacustrine soft clays,using a dynamic tr... In this study,the dynamic characteristics and microstructures of lacustrine soft clays were studied.Dynamic character tests were conducted on undisturbed,remolded,and saturated lacustrine soft clays,using a dynamic triaxial tester.A scanning electron microscope(SEM)was employed to assess the soil samples after dynamic testing.The results indicate that the dynamic characteristics of lacustrine soft clay were significantly affected by confining pressure and water content.A quantitative relationship was established among confining pressures,water content,and the dynamic shear modulus ratio.The dynamic characteristic parameters of undisturbed,remolded and saturated soil are obviously different,and the original structure can enhance the shear strength of soil.By comparing the results with those from other studies,we found that the dynamic characters of soft clays were considerably varied in different regions,and lacustrine soft clays had a larger dynamic shear modulus ratio and a smaller damping ratio when the dynamic shear strain was large.Using IPP software to process the microstructural images,we found that the soil was dominated by small pores and medium particles,and the roundness of pores and particles had an apparently positive correlation with the maximum diameter.Moreover,the pores and particles of the soil showed fractal characteristics and directionality,and the fractal dimensions and probability entropy were strongly correlated with the macrostructural parameters.Finally,we developed a prediction model for macrostructural and microstructural parameters. 展开更多
关键词 lacustrine soft clay dynamic characteristic structural parameter MICROSTRUCTURE probability entropy
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Characterizing the dynamic behavior and progressive damage evolution of carbonaceous slate under cyclic impact loading
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作者 Zhuang Li Nuwen Xu +4 位作者 Zhiqiang Sun Huabo Xiao Can Yang Huaizhong Liu Biao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1060-1072,共13页
Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical... Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical properties and damage mechanisms of carbonaceous slate under cyclic impact loads of varying intensities,cyclic dynamic tests are conducted using a triaxial split Hopkinson pressure bar.This study analyzes the stress-strain relationship,energy damage evolution,and macro-to-micro failure characteristics.The results show that peak stress and strain are significantly influenced by impact intensity and the number of impacts.The initial dynamic stress is positively correlated with the impact intensity,but with more impact,the dynamic stress decreases while the peak strain increases.Energy evolution follows a pattern of"slow growthfluctuating growthrapid growth,"with the crack initiation stress and its proportion decreasing.CT and SEM analyses reveal that as the impact intensity increases,failure becomes more chaotic,the fracture volume increases,and the fracture mode shifts from interlayer and intergranular to through-layer and trans-granular fractures.These findings provide an experimental basis for soft rock tunnel stability analysis. 展开更多
关键词 Split Hopkinson pressure bar Cyclic impact dynamic behavior Cumulative damage MICROSTRUCTURE
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Dynamic characteristics and sensitivity of water hammer problems in liquid propulsion system using lattice Boltzmann method with entropy limiter
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作者 Yuqi WEI Xianggeng WEI +4 位作者 Guoqiang HE Xiao ZHAO Jinying YE Xueren WANG Hongyu CHEN 《Chinese Journal of Aeronautics》 2026年第1期18-34,共17页
The water hammer problem is an important issue in the dynamics of liquid propulsion system.This paper aims to use the Lattice Boltzmann Method(LBM)with entropy limiter to study the water hammer problems in propellant ... The water hammer problem is an important issue in the dynamics of liquid propulsion system.This paper aims to use the Lattice Boltzmann Method(LBM)with entropy limiter to study the water hammer problems in propellant feedlines.The dynamic characteristics of valve-closing water hammer and filling water hammer are investigated by this method,and the sensitivity of filling water hammer is analyzed with a single factor sensitivity analysis with 8 factors and 9 levels and a multi-factor sensitivity analysis with L_(27)(3^(13))orthogonal experiment based on range method.It is found that the solving result of LBM with entropy limiter is basically in good agreement with finite volume method,and using the entropy limiter can eliminate numerical oscillations when solving valve-closing water hammer problems and solve the numerical"blow up"when solving filling water hammer problems.It can be seen that the dynamic characteristics of valve-closing water hammer are relatively simple,while there are many factors that affect the filling water hammer and the degree of these effects varies.The effects on the maximum water hammer pressure are relatively uniform,but those on the water hammer response time vary greatly through the skewness analysis. 展开更多
关键词 dynamic analysis Lattice Boltzmann method Liquid propulsion system Propellant transfer Sensitivity analysis Water hammer
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A Dynamic Masking-Based Multi-Learning Framework for Sparse Classification
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作者 Woo Hyun Park Dong Ryeol Shin 《Computers, Materials & Continua》 2026年第3期1365-1380,共16页
With the recent increase in data volume and diversity,traditional text representation techniques are struggling to capture context,particularly in environments with sparse data.To address these challenges,this study p... With the recent increase in data volume and diversity,traditional text representation techniques are struggling to capture context,particularly in environments with sparse data.To address these challenges,this study proposes a new model,the Masked Joint Representation Model(MJRM).MJRM approximates the original hypothesis by leveraging multiple elements in a limited context.It dynamically adapts to changes in characteristics based on data distribution through three main components.First,masking-based representation learning,termed selective dynamic masking,integrates topic modeling and sentiment clustering to generate and train multiple instances across different data subsets,whose predictions are then aggregated with optimized weights.This design alleviates sparsity,suppresses noise,and preserves contextual structures.Second,regularization-based improvements are applied.Third,techniques for addressing sparse data are used to perform final inference.As a result,MJRM improves performance by up to 4%compared to existing AI techniques.In our experiments,we analyzed the contribution of each factor,demonstrating that masking,dynamic learning,and aggregating multiple instances complement each other to improve performance.This demonstrates that a masking-based multi-learning strategy is effective for context-aware sparse text classification,and can be useful even in challenging situations such as data shortage or data distribution variations.We expect that the approach can be extended to diverse fields such as sentiment analysis,spam filtering,and domain-specific document classification. 展开更多
关键词 Text classification dynamic learning contextual features data sparsity masking-based representation
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Biofilm-state Bifidobacterium adolescentis Gr19 under dynamic culture system effectively alleviates intestinal barrier dysfunction
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作者 Haoxuan Sun Jing Du +4 位作者 Kaisheng Shen Wenyu Ma Xinjie Diao Qi Liu Guorong Liu 《Food Science and Human Wellness》 2026年第1期38-54,共17页
Probiotics can regulate gut microbes to maintain human health.However,the sensitivity of probiotics to environmental conditions reduces their bioavailability.In contrast,the formation of probiotic biofilm provides a n... Probiotics can regulate gut microbes to maintain human health.However,the sensitivity of probiotics to environmental conditions reduces their bioavailability.In contrast,the formation of probiotic biofilm provides a natural physical barrier against external interference.Our previous study established a dynamic culture system of the biofilm-state Bifidobacterium adolescentis Gr19(B-DC-B.adolescentis Gr19),forming higher density and more structurally stable biofilms,which enhanced its potential probiotic properties in vivo.Thus,the protective effect and mechanism of B-DC-B.adolescentis Gr19 on lipopolysaccharide(LPS)-induced intestinal barrier dysfunction were investigated in this study.The results showed that B-DC-B.adolescentis Gr19 not only had high resistance and adhesion activity,but also improved the intestinal barrier by increasing goblet cells and promoting the expression of tight junction(TJ)-related proteins.Moreover,B-DC-B.adolescentis Gr19 effectively attenuated intestinal barrier injury in Caco-2 cells by improving intestinal permeability and integrity.Remarkably,B-DC-B.adolescentis Gr19 enhanced expression of TJ proteins,restored localization of cytoskeleton and reduced intestinal inflammation by suppressing the Ras homolog family member A/Rho-associated coiled-coil-forming kinases/nuclear factor kappa B/myosin light chain kinase/myosin light chain(RhoA/ROCK/NF-κB/MLCK/MLC)pathway.Therefore,B-DC-B.adolescentis Gr19 plays a key role in mitigating LPS-induced intestinal barrier dysfunction.Overall,the present study provides a theoretical basis for ameliorating intestinal barrier dysfunction and developing novel functional foods by using biofilm-state probiotics under dynamic culture. 展开更多
关键词 BIOFILM Bifidobacterium adolescentis dynamic culture system Caco-2 cell In vivo Intestinal barrier dysfunction
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Dynamic Radiative Cooling:Mechanisms,Strategies,and Applications for Smart Thermal Management
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作者 Yan Dong Boxi Tian +7 位作者 Cunhai Wang Guoliang Zhang Fengjiao Hua Weifeng Meng Chunzhe Li Yuying Yan Ziming Cheng Fuqiang Wang 《Nano-Micro Letters》 2026年第5期107-148,共42页
As an emerging thermal management strategy,dynamic radiative cooling(DRC)technology enables dynamic modulation of spectral radiation properties under varying environmental conditions through the directional design of ... As an emerging thermal management strategy,dynamic radiative cooling(DRC)technology enables dynamic modulation of spectral radiation properties under varying environmental conditions through the directional design of material spectral characteristics.However,a comprehensive review of the basic physical mechanisms of radiative heat transfer in DRC materials and various design principles involved in dynamic radiative thermal regulation is still lacking.This review systematically summarizes recent advances in this field,spanning from fundamental physical principles to intrinsic molecular and electronic mechanisms,and further to representative material systems and multi-band regulation strategies,highlighting the interdisciplinary research achievements and technological innovations.This work outlines the core mechanisms governing the regulation of different spectral bands during radiative heat transfer processes.Then,the main categories of DRC materials are systematically reviewed,including actively responsive structures,passively responsive structures,and multi-stimuli-responsive materials.Furthermore,the challenges faced by current DRC technology and future development trends are summarized and discussed,providing valuable reference and guidance for further research in this field.Although DRC technologies still face significant challenges in material stability,manufacturing processes,and system integration,the continuous advances in related areas and multifunctional materials are expected to broaden the application prospects of DRC in the future. 展开更多
关键词 dynamic radiative cooling Solar energy Radiative transfer Radiative regulation Thermal management
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Dynamic psychological vulnerability and adaptation in rheumatoid arthritis:Trajectories,predictors,and interventions
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作者 Xue-Meng Chen Xian Cheng Wei Wu 《World Journal of Psychiatry》 2026年第1期32-46,共15页
Rheumatoid arthritis(RA)patients face significant psychological challenges alongside physical symptoms,necessitating a comprehensive understanding of how psychological vulnerability and adaptation patterns evolve thro... Rheumatoid arthritis(RA)patients face significant psychological challenges alongside physical symptoms,necessitating a comprehensive understanding of how psychological vulnerability and adaptation patterns evolve throughout the disease course.This review examined 95 studies(2000-2025)from PubMed,Web of Science,and CNKI databases including longitudinal cohorts,randomized controlled trials,and mixed-methods research,to characterize the complex interplay between biological,psychological,and social factors affecting RA patients’mental health.Findings revealed three distinct vulnerability trajectories(45%persistently low,30%fluctuating improvement,25%persistently high)and four adaptation stages,with critical intervention periods occurring 3-6 months postdiagnosis and during disease flares.Multiple factors significantly influence psychological outcomes,including gender(females showing 1.8-fold increased risk),age(younger patients experiencing 42%higher vulnerability),pain intensity,inflammatory markers,and neuroendocrine dysregulation(48%showing cortisol rhythm disruption).Early psychological intervention(within 3 months of diagnosis)demonstrated robust benefits,reducing depression incidence by 42%with effects persisting 24-36 months,while different modalities showed complementary advantages:Cognitive behavioral therapy for depression(Cohen’s d=0.68),mindfulness for pain acceptance(38%improvement),and peer support for meaning reconstruction(25.6%increase).These findings underscore the importance of integrating routine psychological assessment into standard RA care,developing stage-appropriate interventions,and advancing research toward personalized biopsychosocial approaches that address the dynamic psychological dimensions of the disease. 展开更多
关键词 Rheumatoid arthritis Psychological vulnerability Disease adaptation ability dynamic changes Mental health
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MimicStudio:One-Stop Development Framework for Dynamic Heterogeneous Redundancy Architecture
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作者 Hu Jingjing Li Yu +3 位作者 Sun Yuanhang Yu Bo Liu Qinrang Wu Jiangxing 《China Communications》 2026年第1期125-139,共15页
Fault-tolerant systems are crucial for ensuring the reliability and availability of missioncritical applications in modern computing environments.The dynamic heterogeneous redundancy(DHR)architecture is a key componen... Fault-tolerant systems are crucial for ensuring the reliability and availability of missioncritical applications in modern computing environments.The dynamic heterogeneous redundancy(DHR)architecture is a key component in constructing fault-tolerant systems,particularly in areas such as national security,power networks,and banking private networks.DHR is transforming the cyberspace security industry chain by accommodating a broader range of applications and increasingly capturing the market.However,the development of applications for DHR architecture encounters challenges due to the complexities of handling heterogeneity,managing dynamism,and maintaining usability.To address these issues,we introduce MimicStudio,a comprehensive development framework with a standardized workflow.To our knowledge,MimicStudio is the first effective solution for DHR software development.We present a detailed implementation of MimicStudio with a heterogeneous microcontroller unit project,encompassing three CPUs with different instruction set architectures.The paper evaluates MimicStudio’s support for essential features,including zero-copy synchronization,parallelized build,multi-core collaborative debugging,and dynamic adjustment of the software system’s structure.Our results show that MimicStudio provides a flexible and efficient solution for supporting the dynamic,heterogeneous,and redundant features of fault-tolerant systems. 展开更多
关键词 cyberspace security development enviroment dynamic heterogeneous redundancy architecture endogenous security MimicStudio
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Quality related fault detection based on dynamic-inner convolutional autoencoder and partial least squares and its application to ironmaking process
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作者 Ping Wu Yuxuan Ni +4 位作者 Huaimin Wang Xuguang Hu Zhenquan Wu Jian Jiang Yaowu Hu 《Chinese Journal of Chemical Engineering》 2026年第1期267-276,共10页
Partial least squares (PLS) model maximizes the covariance between process variables and quality variables,making it widely used in quality-related fault detection.However,traditional PLS methods focus primarily on li... Partial least squares (PLS) model maximizes the covariance between process variables and quality variables,making it widely used in quality-related fault detection.However,traditional PLS methods focus primarily on linear processes,leading to poor performance in dynamic nonlinear processes.In this paper,a novel quality-related fault detection method,named DiCAE-PLS,is developed by combining dynamic-inner convolutional autoencoder with PLS.In the proposed DiCAE-PLS method,latent features are first extracted through dynamic-inner convolutional autoencoder (DiCAE) to capture process dynamics and nonlinearity from process variables.Then,a PLS model is established to build the relationship between the extracted latent features and the final product quality.To detect quality-related faults,Hotelling's T^(2) statistic is employed.The developed quality-related fault detection is applied to the widely used industrial benchmark of the Tennessee. 展开更多
关键词 Partial least squares dynamic-inner convolutional autoencoder Quality-related fault detection Neural networks Safety dynamic modeling
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