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PFC-FDEM multi-scale cross-platform numerical simulation of thermal crack network evolution and SHTB dynamic mechanical response of rocks
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作者 Yue Zhai Shaoxu Hao +1 位作者 Shi Liu Yu Jia 《International Journal of Mining Science and Technology》 2025年第9期1555-1589,共35页
Underground engineering in extreme environments necessitates understanding rock mechanical behavior under coupled high-temperature and dynamic loading conditions.This study presents an innovative multi-scale cross-pla... Underground engineering in extreme environments necessitates understanding rock mechanical behavior under coupled high-temperature and dynamic loading conditions.This study presents an innovative multi-scale cross-platform PFC-FDEM coupling methodology that bridges microscopic thermal damage mechanisms with macroscopic dynamic fracture responses.The breakthrough coupling framework introduces:(1)bidirectional information transfer protocols enabling seamless integration between PFC’s particle-scale thermal damage characterization and FDEM’s continuum-scale fracture propagation,(2)multi-physics mapping algorithms that preserve crack network geometric invariants during scale transitions,and(3)cross-platform cohesive zone implementations for accurate SHTB dynamic loading simulation.The coupled approach reveals distinct three-stage crack evolution characteristics with temperature-dependent density following an exponential model.High-temperature exposure significantly reduces dynamic strength ratio(60%at 800℃)and diminishes strain-rate sensitivity,with dynamic increase factor decreasing from 1.0 to 2.2(25℃)to 1.0-1.3(800℃).Critically,the coupling methodology captures fundamental energy redistribution mechanisms:thermal crack networks alter elastic energy proportion from 75%to 35%while increasing fracture energy from 5%to 30%.Numerical predictions demonstrate excellent experimental agreement(±8%peak stress-strain errors),validating the PFC-FDEM coupling accuracy.This integrated framework provides essential computational tools for predicting complex thermal-mechanical rock behavior in underground engineering applications. 展开更多
关键词 Thermal geomechanics Thermo-mechanical coupling phenomena Fracture network propagation PFC-FDEM Dynamic mechanical response
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M2ATNet: Multi-Scale Multi-Attention Denoising and Feature Fusion Transformer for Low-Light Image Enhancement
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作者 Zhongliang Wei Jianlong An Chang Su 《Computers, Materials & Continua》 2026年第1期1819-1838,共20页
Images taken in dim environments frequently exhibit issues like insufficient brightness,noise,color shifts,and loss of detail.These problems pose significant challenges to dark image enhancement tasks.Current approach... Images taken in dim environments frequently exhibit issues like insufficient brightness,noise,color shifts,and loss of detail.These problems pose significant challenges to dark image enhancement tasks.Current approaches,while effective in global illumination modeling,often struggle to simultaneously suppress noise and preserve structural details,especially under heterogeneous lighting.Furthermore,misalignment between luminance and color channels introduces additional challenges to accurate enhancement.In response to the aforementioned difficulties,we introduce a single-stage framework,M2ATNet,using the multi-scale multi-attention and Transformer architecture.First,to address the problems of texture blurring and residual noise,we design a multi-scale multi-attention denoising module(MMAD),which is applied separately to the luminance and color channels to enhance the structural and texture modeling capabilities.Secondly,to solve the non-alignment problem of the luminance and color channels,we introduce the multi-channel feature fusion Transformer(CFFT)module,which effectively recovers the dark details and corrects the color shifts through cross-channel alignment and deep feature interaction.To guide the model to learn more stably and efficiently,we also fuse multiple types of loss functions to form a hybrid loss term.We extensively evaluate the proposed method on various standard datasets,including LOL-v1,LOL-v2,DICM,LIME,and NPE.Evaluation in terms of numerical metrics and visual quality demonstrate that M2ATNet consistently outperforms existing advanced approaches.Ablation studies further confirm the critical roles played by the MMAD and CFFT modules to detail preservation and visual fidelity under challenging illumination-deficient environments. 展开更多
关键词 Low-light image enhancement multi-scale multi-attention TRANSFORMER
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MewCDNet: A Wavelet-Based Multi-Scale Interaction Network for Efficient Remote Sensing Building Change Detection
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作者 Jia Liu Hao Chen +5 位作者 Hang Gu Yushan Pan Haoran Chen Erlin Tian Min Huang Zuhe Li 《Computers, Materials & Continua》 2026年第1期687-710,共24页
Accurate and efficient detection of building changes in remote sensing imagery is crucial for urban planning,disaster emergency response,and resource management.However,existing methods face challenges such as spectra... Accurate and efficient detection of building changes in remote sensing imagery is crucial for urban planning,disaster emergency response,and resource management.However,existing methods face challenges such as spectral similarity between buildings and backgrounds,sensor variations,and insufficient computational efficiency.To address these challenges,this paper proposes a novel Multi-scale Efficient Wavelet-based Change Detection Network(MewCDNet),which integrates the advantages of Convolutional Neural Networks and Transformers,balances computational costs,and achieves high-performance building change detection.The network employs EfficientNet-B4 as the backbone for hierarchical feature extraction,integrates multi-level feature maps through a multi-scale fusion strategy,and incorporates two key modules:Cross-temporal Difference Detection(CTDD)and Cross-scale Wavelet Refinement(CSWR).CTDD adopts a dual-branch architecture that combines pixel-wise differencing with semanticaware Euclidean distance weighting to enhance the distinction between true changes and background noise.CSWR integrates Haar-based Discrete Wavelet Transform with multi-head cross-attention mechanisms,enabling cross-scale feature fusion while significantly improving edge localization and suppressing spurious changes.Extensive experiments on four benchmark datasets demonstrate MewCDNet’s superiority over comparison methods:achieving F1 scores of 91.54%on LEVIR,93.70%on WHUCD,and 64.96%on S2Looking for building change detection.Furthermore,MewCDNet exhibits optimal performance on the multi-class⋅SYSU dataset(F1:82.71%),highlighting its exceptional generalization capability. 展开更多
关键词 Remote sensing change detection deep learning wavelet transform multi-scale
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EHDC-YOLO: Enhancing Object Detection for UAV Imagery via Multi-Scale Edge and Detail Capture
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作者 Zhiyong Deng Yanchen Ye Jiangling Guo 《Computers, Materials & Continua》 2026年第1期1665-1682,共18页
With the rapid expansion of drone applications,accurate detection of objects in aerial imagery has become crucial for intelligent transportation,urban management,and emergency rescue missions.However,existing methods ... With the rapid expansion of drone applications,accurate detection of objects in aerial imagery has become crucial for intelligent transportation,urban management,and emergency rescue missions.However,existing methods face numerous challenges in practical deployment,including scale variation handling,feature degradation,and complex backgrounds.To address these issues,we propose Edge-enhanced and Detail-Capturing You Only Look Once(EHDC-YOLO),a novel framework for object detection in Unmanned Aerial Vehicle(UAV)imagery.Based on the You Only Look Once version 11 nano(YOLOv11n)baseline,EHDC-YOLO systematically introduces several architectural enhancements:(1)a Multi-Scale Edge Enhancement(MSEE)module that leverages multi-scale pooling and edge information to enhance boundary feature extraction;(2)an Enhanced Feature Pyramid Network(EFPN)that integrates P2-level features with Cross Stage Partial(CSP)structures and OmniKernel convolutions for better fine-grained representation;and(3)Dynamic Head(DyHead)with multi-dimensional attention mechanisms for enhanced cross-scale modeling and perspective adaptability.Comprehensive experiments on the Vision meets Drones for Detection(VisDrone-DET)2019 dataset demonstrate that EHDC-YOLO achieves significant improvements,increasing mean Average Precision(mAP)@0.5 from 33.2%to 46.1%(an absolute improvement of 12.9 percentage points)and mAP@0.5:0.95 from 19.5%to 28.0%(an absolute improvement of 8.5 percentage points)compared with the YOLOv11n baseline,while maintaining a reasonable parameter count(2.81 M vs the baseline’s 2.58 M).Further ablation studies confirm the effectiveness of each proposed component,while visualization results highlight EHDC-YOLO’s superior performance in detecting objects and handling occlusions in complex drone scenarios. 展开更多
关键词 UAV imagery object detection multi-scale feature fusion edge enhancement detail preservation YOLO feature pyramid network attention mechanism
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Identification of small impact craters in Chang’e-4 landing areas using a new multi-scale fusion crater detection algorithm
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作者 FangChao Liu HuiWen Liu +7 位作者 Li Zhang Jian Chen DiJun Guo Bo Li ChangQing Liu ZongCheng Ling Ying-Bo Lu JunSheng Yao 《Earth and Planetary Physics》 2026年第1期92-104,共13页
Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious an... Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious and they are numerous,resulting in low detection accuracy by deep learning models.Therefore,we proposed a new multi-scale fusion crater detection algorithm(MSF-CDA)based on the YOLO11 to improve the accuracy of lunar impact crater detection,especially for small craters with a diameter of<1 km.Using the images taken by the LROC(Lunar Reconnaissance Orbiter Camera)at the Chang’e-4(CE-4)landing area,we constructed three separate datasets for craters with diameters of 0-70 m,70-140 m,and>140 m.We then trained three submodels separately with these three datasets.Additionally,we designed a slicing-amplifying-slicing strategy to enhance the ability to extract features from small craters.To handle redundant predictions,we proposed a new Non-Maximum Suppression with Area Filtering method to fuse the results in overlapping targets within the multi-scale submodels.Finally,our new MSF-CDA method achieved high detection performance,with the Precision,Recall,and F1 score having values of 0.991,0.987,and 0.989,respectively,perfectly addressing the problems induced by the lesser features and sample imbalance of small craters.Our MSF-CDA can provide strong data support for more in-depth study of the geological evolution of the lunar surface and finer geological age estimations.This strategy can also be used to detect other small objects with lesser features and sample imbalance problems.We detected approximately 500,000 impact craters in an area of approximately 214 km2 around the CE-4 landing area.By statistically analyzing the new data,we updated the distribution function of the number and diameter of impact craters.Finally,we identified the most suitable lighting conditions for detecting impact crater targets by analyzing the effect of different lighting conditions on the detection accuracy. 展开更多
关键词 impact craters Chang’e-4 landing area multi-scale automatic detection YOLO11 Fusion algorithm
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Seismic response of adjacent buildings considering structure-soil-structure interaction
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作者 Hamzeh Ahmadi Reza Alinejad Maziar Fahimi Farzam 《Earthquake Engineering and Engineering Vibration》 2026年第1期255-277,共23页
This study examines the dynamic response of two adjacent 9-and 20-story benchmark steel buildings subjected to six near-fault earthquake records.Two-dimensional numerical models were employed to account for the comple... This study examines the dynamic response of two adjacent 9-and 20-story benchmark steel buildings subjected to six near-fault earthquake records.Two-dimensional numerical models were employed to account for the complexities of structure-soil-structure interaction(SSSI).The research focuses on the separation gap between the buildings and the effects of pounding while considering Fixed Base(FB)and SSSI models,evaluated according to UBC 94 and ASCE 7-16 seismic codes.Key findings reveal that pounding occurs with the UBC 94 separation gap when earthquake frequency aligns with system frequency,leading to increased column stresses in the 9-story building.In contrast,the ASCE 7-16 standard effectively prevents pounding in both the FB and SSSI models.Additionally,drifts and displacements of lower floors in SSSI models exceed the allowable limits of ASCE 7-16,underscoring the impact of soil-structure interaction on seismic response. 展开更多
关键词 structure-soil-structure interaction separation gap POUNDING nonlinear analysis near-fault earthquake seismic response
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Metal(loid)accumulation and foliar physiological responses in Oryza sativa L.induced by PM1 exposure from various emission sources
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作者 Meixuan Fang Yue Yang +4 位作者 Baofeng Zhang Yingluo Chen Jingdong Mao Liping Lou Qi Lin 《Journal of Environmental Sciences》 2026年第1期585-595,共11页
Foliar uptake of airborne metal(loid)s plays a crucial role in metal(loid)accumulation in plant organs and is influ-enced by the size and emission sources of aerosols.Given the high enrichment of toxic metal(loid)s in... Foliar uptake of airborne metal(loid)s plays a crucial role in metal(loid)accumulation in plant organs and is influ-enced by the size and emission sources of aerosols.Given the high enrichment of toxic metal(loid)s in submicron-scale particulates(PM1),this study established a PM1 exposure system to examine airborne metal(loid)accu-mulation and foliar physiological responses in Oryza sativa L.The results showed that the concentrations of Cu,Zn,As,Pb,and Cd in the leaves and grains were influenced not only by the airborne metal(loid)levels but also by the specific nature of the PM1 particles.The quantitative model for PM1-associated Pb entry into leaf tissue indicated that foliar Pb accumulation was primarily driven by particle adhesion,followed by hydrophilic pene-tration and trans-stomatal liquid film migration,accounting for 87%–89%of the total accumulation.The strong hygroscopicity and high Pb activity of PM1 emitted from waste incineration(WI)increased the Pb absorption coefficient via the hydrophilic and liquid film migration pathway.In contrast,the high hydrophobicity of PM1 from coal burning(CB)led to greater retention of Pb on leaf surfaces.Both foliar reactive oxygen metabolism and photosynthesis indices were sensitive to air pollution.Foliar metal(loid)accumulation and airborne PM1 concentration accounted for the variance in physiological responses in rice leaves.Our results also indicated that Pb was the key element in PM1 emissions from both coal burning(CB)and waste incineration(WI)responsible for significant physiological changes in rice leaves. 展开更多
关键词 Metal(loid) PM1 exposure Coal burning Waste incineration Physiological response Particle nature
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Lactylation modification of prostate apoptosis response protein-4(PAR-4)p otential driving immune tolerance of hepatocellular carcinoma cells
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作者 Xue-Qin Wu Meng-Sen Li 《Cancer Advances》 2026年第1期1-4,共4页
Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immun... Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immune tolerance of cancer cells.The classical theory holds that prostate apoptosis response-4(PAR-4)is a tumor suppressor protein.However,our recent research has found that PAR-4 has a biological function of promoting cancer in hepatocellular carcinoma(HCC),and our analysis shows that PAR-4 can be modified of lactic acid.These research evidences suggest that PAR-4 lactylation modification may drive immune tolerance in HCC.Therefore,inhibiting PAR-4 lactylation modification is very likely to increase the sensitivity of HCC to immunotherapy. 展开更多
关键词 hepatocellular carcinoma lactylation promoting cancer prostate apoptosis response protein lactic acid modification immune tolerance lactylation modification regulate immune tolerance
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Study on response of AlphaGUARD PQ2000 radon monitor to^(220)Rn and its long‑lived progeny in diffusion mode
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作者 Ke‑Xin Wang Zheng‑Zhong He +6 位作者 Ya‑Song Xiao Jia‑Lu Feng Yan‑Bing Lin Wen‑Jie Xu Li‑Dan Lv Yu‑Qi Xing Hui‑Min Yuan 《Nuclear Science and Techniques》 2026年第1期152-163,共12页
Owing to the inherent limitation of the internal pulse ionization chamber within the AlphaGUARD PQ2000 radon monitor,that is,its inability to discriminate the energy levels of α particles,the ingress of^(220)Rn from ... Owing to the inherent limitation of the internal pulse ionization chamber within the AlphaGUARD PQ2000 radon monitor,that is,its inability to discriminate the energy levels of α particles,the ingress of^(220)Rn from the surrounding environment,along with its decay progeny,poses a substantive challenge in accurately determining the^(222)Rn concentration in the measurement outcomes.Among these,the protracted influence primarily stems from the two enduring decay progenies,namely^(212)Pb with a half-life of 10.64 h and^(212)Bi with a half-life of 60.54 min.This study explored the influence of^(220)Rn progeny on the measurement results of an AlphaGUARD PQ2000 radon monitor by developing a theoretical calculation model.The response coefficient related to the residual^(220)Rn progeny within the AlphaGUARD PQ2000 radon monitor was experimentally validated.In addition,this study investigated the effects of temperature and wind speed on the sensitivity of the instrument to^(220)Rn gas.The research findings revealed commendable agreement between the experimentally measured response coefficients of the residual^(220)Rn progeny and the corresponding values derived from the theoretical model.Notably,both the response coefficients of the AlphaGUARD PQ2000 radon monitor to^(220)Rn gas and its internal residual^(220)Rn progeny increased with elevated temperatures and increased wind speeds,providing a reference for correcting the impact of^(220)Rn and its progeny on the measurement results of^(222)Rn concentration obtained using the AlphaGUARD PQ2000 radon monitor. 展开更多
关键词 ^(220)Rn progeny 222Rn AlphaGUARD PQ2000 Long-term decay response coefficient ^(220)Rn gas Temperature effects Wind speed effects
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The Yin-Yang of Stress and Senescence:Integrated Stress Response and SASP Crosstalk in Stem Cell Fate,Regeneration,and Disease
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作者 Douglas M.Ruden 《BIOCELL》 2026年第1期11-27,共17页
Stem cell fate decisions are increasingly understood through the dynamic interplay of two fundamental stress-adaptive programs:the integrated stress response(ISR)and the senescence-associated secretory phenotype(SASP)... Stem cell fate decisions are increasingly understood through the dynamic interplay of two fundamental stress-adaptive programs:the integrated stress response(ISR)and the senescence-associated secretory phenotype(SASP).These pathways act as a Yin-Yang system,balancing beneficial and detrimental outcomes across development,tissue homeostasis,and disease.On the yin(protective)side,transient ISR activation and acute SASP signaling foster adaptation,embryonic patterning,wound healing,and regeneration.On the yang(maladaptive)side,chronic ISR signaling and unresolved SASP output drive stem cell exhaustion,fibrosis,inflammation,and tumorigenesis.This duality highlights their roles as both guardians and disruptors of stem cell integrity.Mechanistically,ISR regulates translational control via eukaryotic initiation factor 2 alpha(eIF2α)phosphorylation and activating transcription factor 4(ATF4)-dependent transcription,while SASP reprograms the extracellular milieu through cytokines,growth factors,and proteases.Their crosstalk creates feedback loops that shape tissue niches and long-termstemcell potential.Framing ISR-SASP interactions through a Yin-Yang lens underscores the balance between resilience and decline,to offer new insights into regenerative medicine,anti-aging interventions,and cancer therapeutics. 展开更多
关键词 Integrated stress response(ISR) senescence-associated secretory phenotype(SASP) stem cells activating transcription factor 4(ATF4) eukaryotic initiation factor 2 alpha(eIF2α) inflammation cancer
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Response of the North Pacific Storm Track Activity in the Cold Season to Multi-scale Oceanic Variations of Kuroshio Extension System: A Statistical Assessment 被引量:1
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作者 Peilong YU Minghao YANG +3 位作者 Chao ZHANG Yi LI Lifeng ZHANG Shiyao CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第3期514-530,共17页
In this paper,a statistical method called Generalized Equilibrium Feedback Analysis(GEFA)is used to investigate the responses of the North Pacific Storm Track(NPST)in the cold season to the multi-scale oceanic variati... In this paper,a statistical method called Generalized Equilibrium Feedback Analysis(GEFA)is used to investigate the responses of the North Pacific Storm Track(NPST)in the cold season to the multi-scale oceanic variations of the Kuroshio Extension(KE)system,including its large-scale variation,oceanic front meridional shift,and mesoscale eddy activity.Results show that in the cold season from the lower to the upper troposphere,the KE large-scale variation significantly weakens the storm track activity over the central North Pacific south of 30°N.The northward shift of the KE front significantly strengthens the storm track activity over the western and central North Pacific south of 40°N,resulting in a southward shift of the NPST.In contrast,the NPST response to KE mesoscale eddy activity is not so significant and relatively shallow,which only shows some significant positive signals near the dateline in the lower and middle troposphere.Furthermore,it is found that baroclinicity and baroclinic energy conversion play an important role in the formation of the NPST response to the KE multi-scale oceanic variations. 展开更多
关键词 generalized equilibrium feedback analysis Kuroshio Extension multi-scale oceanic variations North Pacific storm track
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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 review on multi-scale structure engineering of carbon-based electrode materials towards dense energy storage for supercapacitors 被引量:1
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作者 Dongyang Wu Fei Sun +5 位作者 Min Xie Hua Wang Wei Fan Jihui Gao Guangbo Zhao Shaoqin Liu 《Journal of Energy Chemistry》 2025年第3期768-799,共32页
Improving the volumetric energy density of supercapacitors is essential for practical applications,which highly relies on the dense storage of ions in carbon-based electrodes.The functional units of carbon-based elect... Improving the volumetric energy density of supercapacitors is essential for practical applications,which highly relies on the dense storage of ions in carbon-based electrodes.The functional units of carbon-based electrode exhibit multi-scale structural characteristics including macroscopic electrode morphologies,mesoscopic microcrystals and pores,and microscopic defects and dopants in the carbon basal plane.Therefore,the ordered combination of multi-scale structures of carbon electrode is crucial for achieving dense energy storage and high volumetric performance by leveraging the functions of various scale structu re.Considering that previous reviews have focused more on the discussion of specific scale structu re of carbon electrodes,this review takes a multi-scale perspective in which recent progresses regarding the structureperformance relationship,underlying mechanism and directional design of carbon-based multi-scale structures including carbon morphology,pore structure,carbon basal plane micro-environment and electrode technology on dense energy storage and volumetric property of supercapacitors are systematically discussed.We analyzed in detail the effects of the morphology,pore,and micro-environment of carbon electrode materials on ion dense storage,summarized the specific effects of different scale structures on volumetric property and recent research progress,and proposed the mutual influence and trade-off relationship between various scale structures.In addition,the challenges and outlooks for improving the dense storage and volumetric performance of carbon-based supercapacitors are analyzed,which can provide feasible technical reference and guidance for the design and manufacture of dense carbon-based electrode materials. 展开更多
关键词 SUPERCAPACITORS Carbon-based electrodes Volumetric performances multi-scale structure Dense energy storage
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Hydrodynamic Performance and Structural Response of a Sharp Eagle Wave Energy Converter Platform Under Extreme Sea States 被引量:1
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作者 YUE Wan-zhen WANG Kun-lin +4 位作者 JIANG Jia-qiang SHENG Song-wei LU Wen-zhao HE Teng YANG Xian-yuan 《China Ocean Engineering》 2025年第2期373-382,共10页
This paper presents a new type of triangular Sharp Eagle wave energy converter(WEC)platform.On the basis of the linear potential flow theory and the finite element analysis method,the hydrodynamic performance and stru... This paper presents a new type of triangular Sharp Eagle wave energy converter(WEC)platform.On the basis of the linear potential flow theory and the finite element analysis method,the hydrodynamic performance and structural response of the platform are studied,considering the actual platform motion and free surface rise under extreme sea states.First,the effects of the wave frequency and direction on the wave-induced loads and dynamic responses were examined.The motion at a wave direction angle of 0°is relatively low.On this basis,the angle constrained by the two sides of the Sharp Eagle floaters should be aligned with the main wave direction to avoid significant platform motion under extreme sea states.Additionally,the structural response of the platform,including the wave-absorbing floaters,is investigated.The results highlighted that the conditions or locations where yielding,buckling,and fatigue failures occur were different.In this context,the connection area of the Sharp Eagle floaters and platform is prone to yielding failure under oblique wave action,whereas the pontoon and side of the Sharp Eagle floaters are prone to buckling failure during significant vertical motion.Additionally,fatigue damage is most likely to occur at the connection between the middle column on both sides of the Sharp Eagle floaters and the pontoons.The findings of this paper revealed an intrinsic connection between wave-induced loads and the dynamic and structural responses of the platform,which provides a useful reference for the improved design of WECs. 展开更多
关键词 wave energy converter extreme sea states finite element analysis dynamic response structural response
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M2ANet:Multi-branch and multi-scale attention network for medical image segmentation 被引量:1
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作者 Wei Xue Chuanghui Chen +3 位作者 Xuan Qi Jian Qin Zhen Tang Yongsheng He 《Chinese Physics B》 2025年第8期547-559,共13页
Convolutional neural networks(CNNs)-based medical image segmentation technologies have been widely used in medical image segmentation because of their strong representation and generalization abilities.However,due to ... Convolutional neural networks(CNNs)-based medical image segmentation technologies have been widely used in medical image segmentation because of their strong representation and generalization abilities.However,due to the inability to effectively capture global information from images,CNNs can easily lead to loss of contours and textures in segmentation results.Notice that the transformer model can effectively capture the properties of long-range dependencies in the image,and furthermore,combining the CNN and the transformer can effectively extract local details and global contextual features of the image.Motivated by this,we propose a multi-branch and multi-scale attention network(M2ANet)for medical image segmentation,whose architecture consists of three components.Specifically,in the first component,we construct an adaptive multi-branch patch module for parallel extraction of image features to reduce information loss caused by downsampling.In the second component,we apply residual block to the well-known convolutional block attention module to enhance the network’s ability to recognize important features of images and alleviate the phenomenon of gradient vanishing.In the third component,we design a multi-scale feature fusion module,in which we adopt adaptive average pooling and position encoding to enhance contextual features,and then multi-head attention is introduced to further enrich feature representation.Finally,we validate the effectiveness and feasibility of the proposed M2ANet method through comparative experiments on four benchmark medical image segmentation datasets,particularly in the context of preserving contours and textures. 展开更多
关键词 medical image segmentation convolutional neural network multi-branch attention multi-scale feature fusion
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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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Mechanical response analysis of asphalt pavement considering top-down crack based on FDM-DEM coupling simulation 被引量:2
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作者 Min Wang Xin Yu Chen Chen 《Journal of Road Engineering》 2025年第1期92-105,共14页
The occurrence of top-down(TD)cracking has gradually become a prevalent issue in semi-rigid base asphalt pavements after prolonged service.A coupled simulation model integrating the finite difference method(FDM)and di... The occurrence of top-down(TD)cracking has gradually become a prevalent issue in semi-rigid base asphalt pavements after prolonged service.A coupled simulation model integrating the finite difference method(FDM)and discrete element method(DEM)was employed to investigate the mechanical behavior of asphalt pavement containing a pre-existing TD crack.The mesoscopic parameters of the model were calibrated based on the mixture modulus and the static mechanical response on the MLS66 test road.Finally,an analysis was performed to assess how variations in TD crack depth and longitudinal length affect the distribution patterns of transverse tensile stress,vertical shear stress,and vertical compressive stress.The results indicate that the vertical propagation of TD crack significantly increases both the tensile stress value and range on the middle surface,while the longitudinal development of TD crack has minimal impact.This phenomenon may result in more severe fatigue failure on the middle surface.With the vertical and longitudinal development of TD crack,the vertical shear stress and compressive stress show obvious"two-stage"characteristics.When the crack's vertical length reaches 40 mm,there is a sharp increase in stress on the upper surface.As the crack continues to propagate vertically,the growth of stress on the upper surface becomes negligible,while the stress in the middle and lower layers increased significantly.Conversely,for longitudinal development of TD crack,any changes in stress are insignificant when their length is less than 180 mm;however,as they continue to develop longitudinally beyond this threshold,there is a sharp increase in stress levels.These findings hold great significance for understanding pavement structure deterioration and maintenance behavior associated with TD crack. 展开更多
关键词 Full-scale pavement structure Top-down crack FDM-DEM coupling model Mechanical response
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Evidence-based control of stress response on intraoperative physiological indexes and recovery of patients undergoing gastrointestinal surgery 被引量:3
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作者 Chen-Dong Yuan Bao-Zhu Zhou +2 位作者 Ning-Yan Wang Qing-Qing Wan Zhen-Zhen Hu 《World Journal of Gastroenterology》 2025年第8期72-81,共10页
BACKGROUND Although the 2021 Chinese Clinical Practice Guidelines for Enhanced Recovery after Surgery(ERAS)provide recommendations for ERAS in gastrointestinal surgery,the clinical application of standard ERAS nursing... BACKGROUND Although the 2021 Chinese Clinical Practice Guidelines for Enhanced Recovery after Surgery(ERAS)provide recommendations for ERAS in gastrointestinal surgery,the clinical application of standard ERAS nursing models is challenging due to the variety of diseases involved in gastrointestinal surgery and the com-plex factors contributing to patient stress responses.Moreover,stress responses are more severe in older adult patients.Therefore,precision medicine is required to improve the quality of nursing care and promote postoperative recovery in gastrointestinal surgery.and demonstrate nursing benefits through clinical practice.METHODS This randomized clinical trial first established an evidence-based nursing ERAS protocol in older adult patients based on literature related to perioperative nursing measures for gastrointestinal surgery stress response.Next,392 older adult patients who underwent gastrointestinal surgery and were admitted to our hospital between December 2021 and June 2023 were categorized into two groups to receive evidence-based(study group)or conventional(control group)ERAS nursing models,respectively.Intraoperative physiological parameters during surgery and postoperative recovery indicators were compared between the groups.RESULTS Among 64 domestic and international studies,the stress responses of older adult patients mainly included emotional anxiety,sleep disorders,gastrointestinal discomfort,physical weakness,pain,and swelling.The appropriate nursing interventions included comprehensive psychological counseling,pre-and postoperative nutritional support,temperature control,pain management,and rehabilitation training.Compared with the control group,the study group showed lower heart rate,mean arterial pressure,blood glucose level,and adrenaline level;shorter duration of drainage tube placement,time to first flatus,time to first ambulation,and postoperative hospital stay;lower anxiety scores on postoperative day 3;and lower incidences of postoperative infection,obstruction,poor wound healing,and gastrointestinal reactions were lower in the study group(all P<0.05).CONCLUSION The evidence-based nursing measures targeting stress responses based on the conventional ERAS nursing model resulted in stable intraoperative physiological parameters during surgery,promoted postoperative recovery,and reduced the incidence of complications. 展开更多
关键词 Older adult patients Gastrointestinal surgery Stress response Evidence-based nursing Enhanced recovery after surgery
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DNA Damage Response and Its Inhibitors:Current Perspectives and Future Directions 被引量:1
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作者 ZHENG Xueyi XIE Dan CAI Muyan 《中国细胞生物学学报》 2025年第3期542-559,共18页
The DDR(DNA damage response)is an essential cellular mechanism that detects and repairs DNA lesions to maintain genomic stability.Dysregulation of DDR pathways is frequently observed in human tumors,leading to increas... The DDR(DNA damage response)is an essential cellular mechanism that detects and repairs DNA lesions to maintain genomic stability.Dysregulation of DDR pathways is frequently observed in human tumors,leading to increased genomic instability and promoting tumor progression.Consequently,targeting DDR mechanisms has emerged as a promising therapeutic strategy in oncology.This review provides an overview of the major DDR pathways,highlighting the roles of key proteins involved in various DDR processes.A detailed understanding of these molecular mechanisms has paved the way for the development of targeted antitumor agents,including inhibitors of PARP1,ATM,ATR,CHK1,CHK2,DNA-PK,and WEE1.Additionally,the significant challenges in the development of DDR inhibitors are examined,including tumor microenvironment heterogeneity,resistance mechanisms,issues with selectivity and toxicity,and the complexities associated with clinical trial design.Finally,future directions and emerging strategies to improve DDR-targeted therapies are discussed.These strategies include biomarker-driven precision medicine,novel combination therapies,advanced drug delivery systems,and the potential application of artificial intelligence to optimize treatment outcomes. 展开更多
关键词 DNA damage response INHIBITOR BIOMARKER
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Analysis of vibration response characteristics of subway station and superstructure with hard combination 被引量:1
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作者 Jia Jinglong Xu Weiping +1 位作者 Liu Xu Wei Yong 《Earthquake Engineering and Engineering Vibration》 2025年第1期271-281,共11页
The vibration response and noise caused by subway trains can affect the safety and comfort of superstructures.To study the dynamic response characteristics of subway stations and superstructures under train loads with... The vibration response and noise caused by subway trains can affect the safety and comfort of superstructures.To study the dynamic response characteristics of subway stations and superstructures under train loads with a hard combination,a numerical model is developed in this study.The indoor model test verified the accuracy of the numerical model.The influence laws of different hard combinations,train operating speeds and modes were studied and evaluated accordingly.The results show that the frequency corresponding to the peak vibration acceleration level of each floor of the superstructure property is concentrated at 10–20 Hz.The vibration response decreases in the high-frequency parts and increases in the lowfrequency parts with increasing distance from the source.Furthermore,the factors,such as train operating speed,operating mode,and hard combination type,will affect the vibration of the superstructure.The vibration response under the reversible operation of the train is greater than that of the unidirectional operation.The operating speed of the train is proportional to its vibration response.The vibration amplification area appears between the middle and the top of the superstructure at a higher train speed.Its vibration acceleration level will exceed the limit value of relevant regulations,and vibration-damping measures are required.Within the scope of application,this study provides some suggestions for constructing subway stations and superstructures. 展开更多
关键词 subway station SUPERSTRUCTURE vibration response hard combination
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