期刊文献+
共找到309,146篇文章
< 1 2 250 >
每页显示 20 50 100
MDGET-MER:Multi-Level Dynamic Gating and Emotion Transfer for Multi-Modal Emotion Recognition
1
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
在线阅读 下载PDF
UGEA-LMD: A Continuous-Time Dynamic Graph Representation Enhancement Framework for Lateral Movement Detection
2
作者 Jizhao Liu Yuanyuan Shao +2 位作者 Shuqin Zhang Fangfang Shan Jun Li 《Computers, Materials & Continua》 2026年第1期1924-1943,共20页
Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address thes... Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address these challenges,we propose an Uncertainty-Driven Graph Embedding-Enhanced Lateral Movement Detection framework(UGEA-LMD).First,the framework employs event-level incremental encoding on a continuous-time graph to capture fine-grained behavioral evolution,enabling newly appearing nodes to retain temporal contextual awareness even in the absence of historical interactions and thereby fundamentally mitigating the cold-start problem.Second,in the embedding space,we model the dependency structure among feature dimensions using a Gaussian copula to quantify the uncertainty distribution,and generate augmented samples with consistent structural and semantic properties through adaptive sampling,thus expanding the representation space of sparse samples and enhancing the model’s generalization under sparse sample conditions.Unlike static graph methods that cannot model temporal dependencies or data augmentation techniques that depend on predefined structures,UGEA-LMD offers both superior temporaldynamic modeling and structural generalization.Experimental results on the large-scale LANL log dataset demonstrate that,under the transductive setting,UGEA-LMD achieves an AUC of 0.9254;even when 10%of nodes or edges are withheld during training,UGEA-LMD significantly outperforms baseline methods on metrics such as recall and AUC,confirming its robustness and generalization capability in sparse-sample and cold-start scenarios. 展开更多
关键词 Advanced persistent threat(APTs) lateral movement detection continuous-time dynamic graph data enhancement
在线阅读 下载PDF
结合TG-TDLAS与ReaxFF MD的烟煤热解CH_(4)生成机理研究
3
作者 王庚乾 王远洋 +7 位作者 李光跃 田亚莉 和小虎 邱选兵 李传亮 梁五洲 姚凯 张君瑞 《光学精密工程》 北大核心 2026年第6期861-873,共13页
为了从原子尺度揭示烟煤热解过程中甲烷(CH_(4))的生成机理,以弥补传统实验手段难以捕捉其反应前驱体与微观路径的不足,本研究采用了热重-可调谐半导体激光吸收光谱(TG-TDLAS)实验与反应分子动力学模拟(ReaxFF MD)相结合的方法。首先,通... 为了从原子尺度揭示烟煤热解过程中甲烷(CH_(4))的生成机理,以弥补传统实验手段难以捕捉其反应前驱体与微观路径的不足,本研究采用了热重-可调谐半导体激光吸收光谱(TG-TDLAS)实验与反应分子动力学模拟(ReaxFF MD)相结合的方法。首先,通过TG-TDLAS实验获取了CH_(4)生成的宏观温度依赖性与动力学行为。其次,基于对烟煤样品的元素分析、红外光谱和^(13)C核磁共振表征,构建了烟煤分子模型(C_(309)H_(203)N_(3)O_(18)),并利用ReaxFF MD模拟分析了不同温度下CH_(3)自由基的断裂、氢迁移及CH_(4)生成的动态反应过程。结果表明,实验测得CH_(4)生成主要集中于450~750℃,峰值约600℃;模拟则揭示了CH_(4)生成的微观机理,即侧链CH_(3)在约1100 K断裂生成自由基,随后通过夺取邻近氢原子转化为CH_(4),并在2500 K达到峰值,两者在生成趋势上高度一致。结论认为,该方法从宏微观层面系统阐明了CH_(4)的生成源于前驱体断裂与氢夺取的平衡过程,验证了ReaxFF MD在揭示煤热解复杂反应网络中中间体行为的独特优势,为理解煤自燃、裂解路径及提高能源转化效率提供了理论依据。 展开更多
关键词 ReaxFF md 热解 煤分子模型 CH_(4)
在线阅读 下载PDF
几类MDS码和NMDS码的构造
4
作者 杜小妮 薛婧 +1 位作者 乔兴斌 赵紫薇 《西北师范大学学报(自然科学版)》 2026年第1期41-48,共8页
MDS码是参数达到Singleton界的最优线性码,广泛应用于分布式存储系统和随机误差信道等领域.与之密切相关的NMDS码在保持近似纠错性能的同时,可以显著降低编译码复杂度,因此成为编码理论研究的热点之一.通过选取有限域F_(q^(2))(其中q为... MDS码是参数达到Singleton界的最优线性码,广泛应用于分布式存储系统和随机误差信道等领域.与之密切相关的NMDS码在保持近似纠错性能的同时,可以显著降低编译码复杂度,因此成为编码理论研究的热点之一.通过选取有限域F_(q^(2))(其中q为2的幂次)上单位圆盘中的元素来构造矩阵,并在其中添加一个列向量,将其作为生成矩阵构造了F_(q^(2))上几类码长为(q+2)的MDS码和NMDS码,研究了NMDS码的重量计数器;选取F_(q^(t))(t≥1为整数)中含有l(4<l≤q^(t))个元素的集合构造了码长为l的MDS码.研究发现,构造的MDS码均为Griesmer码,NMDS码均为near Griesmer码;码本表明,本文构造的所有码均为新码. 展开更多
关键词 mdS码 NmdS码 重量计数器 Griesmer界
在线阅读 下载PDF
基于ReaxFF-MD模拟的木质素-Fe基载氧体-水蒸气体系的化学链气化特性
5
作者 穆林 李延宇 +3 位作者 孙萌 王震 尚妍 东明 《洁净煤技术》 北大核心 2026年第3期15-26,共12页
化学链气化技术是一种新兴的能源转化技术,具有重要的研究和应用价值,近年来随着清洁能源需求的增加,该技术在生物质和煤炭气化领域的研究逐渐深入。为探索木质素在铁基载氧体作用下的化学链气化反应机理及过程,采用ReaxFF-MD模拟方法,... 化学链气化技术是一种新兴的能源转化技术,具有重要的研究和应用价值,近年来随着清洁能源需求的增加,该技术在生物质和煤炭气化领域的研究逐渐深入。为探索木质素在铁基载氧体作用下的化学链气化反应机理及过程,采用ReaxFF-MD模拟方法,以Fe_(2)O_(3)为载氧体对木质素化学链气化过程进行模拟。结果表明:Fe_(2)O_(3)不仅可以促进木质素的热解,而且能够提供晶格氧加强焦油和焦炭的裂解转化;提高温度可以增加CO和H_(2)的产量,提高木质素的热解气化效率;载氧体与生物质物质的量比的增大可以促进CO的生成,获得高产率的合成气。当两者的物质的量比为2.5时,合成气产率最大,为47.65%。为探究生物质组分变化的影响,以Fe_(2)O_(3)为载氧体对纤维素与木质素共存体系进行化学链气化模拟,结果表明:当纤维素与木质素物质的量比为3∶7时,体系拥有最大的合成气产率33.97%,此时的合成气热值更高。此外,对比尖晶石NiFe_(2)O_(4)和Fe_(2)O_(3)性能发现,NiFe_(2)O_(4)能够为木质素化学链气化过程提供更多的晶格氧,不仅能够提高氢气的产率,有利于木质素向合成气的高效清洁转化,也能够提高碳转化率,满足当前减碳排放的目标要求。 展开更多
关键词 化学链气化 木质素 铁基载氧体 气化特性 ReaxFF-md
在线阅读 下载PDF
基于POD/DMD的液力透平尾涡逆射流非定常解耦
6
作者 王晓晖 马克浩 +1 位作者 苗森春 杨军虎 《华中科技大学学报(自然科学版)》 北大核心 2026年第1期121-126,134,共7页
液力透平尾流场存在与叶轮旋向相反的大尺度螺旋涡,涡核中心发现沿轴向的逆流现象,对装置的效率和运行稳定性有影响.结合本征正交分解(POD)和动态模态分解(DMD)两种降阶模型在流场解耦的不同优势,对逆射流的流动特征及演化规律进行分析... 液力透平尾流场存在与叶轮旋向相反的大尺度螺旋涡,涡核中心发现沿轴向的逆流现象,对装置的效率和运行稳定性有影响.结合本征正交分解(POD)和动态模态分解(DMD)两种降阶模型在流场解耦的不同优势,对逆射流的流动特征及演化规律进行分析.研究结果表明:逆射流在叶轮的动静干涉和大尺度尾涡破碎的作用下发生周期性振动,并在演化过程中引起尾流场大尺度涡运动和流动分离;POD方法和DMD方法的低阶模态反映出由旋转叶轮和尾水管之间动静干涉的流动结构特征,主导频率接近叶轮转频;高阶模态则反映出逆射流下游小尺度离散涡团破碎-融合-衰减过程的流动特征,模态频率接近叶轮转频的整数倍. 展开更多
关键词 液力透平 逆射流 降阶模型 本征正交分解 动态模态分解
原文传递
LCD MDS码的最新研究进展
7
作者 乔兴斌 杜小妮 《西北师范大学学报(自然科学版)》 2026年第1期15-22,共8页
线性互补对偶(Linear Complementary Dual,LCD)码因其在数据存储和密码学方面的显著作用而受到广泛研究.极大距离可分(Maximum Distance Separable,MDS)码具有最优的纠错能力,因而构造LCD MDS码是编码理论研究的一个热点.利用Goppa码、... 线性互补对偶(Linear Complementary Dual,LCD)码因其在数据存储和密码学方面的显著作用而受到广泛研究.极大距离可分(Maximum Distance Separable,MDS)码具有最优的纠错能力,因而构造LCD MDS码是编码理论研究的一个热点.利用Goppa码、扭曲广义Reed-Solomon码和斜群码等可以给出LCD MDS码的显式构造.本文回顾了2020年以来LCD MDS码研究的最新进展,并总结了该领域一些悬而未决的问题. 展开更多
关键词 线性码 线性互补对偶码 mdS码 Goppa码 扭曲广义Reed-Solomon码
在线阅读 下载PDF
Effect of Demineralization on Pyrolysis Reactivity of Zhundong Coal by Reactive Force Field Molecular Dynamics(ReaxFF MD)Simulation
8
作者 Qian Lin Tao Chao +2 位作者 Zhao Nanjin Kuang Panyang Guo Feiqiang 《燃烧科学与技术》 北大核心 2025年第4期353-366,共14页
It is important to understand the effects of demineralization on the reactivity of coal pyrolysis for demineralization coal in OCCSS systems.The molecular dynamics of the pyrolysis of ZD-R and ZD-D was investigated us... It is important to understand the effects of demineralization on the reactivity of coal pyrolysis for demineralization coal in OCCSS systems.The molecular dynamics of the pyrolysis of ZD-R and ZD-D was investigated using the ReaxFF MD method.It is indicated that the pyrolysis reactivity of ZD-D is enhanced.Acid demineralization treatment helps to enhance the cross-linking reaction of light tar C5-14 molecules in the main pyrolysis stage,generating light tar fragments with higher molecular mass.In the polycondensation pyrolysis stage,the acid demineralization treatment promotes the polycondensation reaction at high temperatures.The generation of H2 in ZD-R pyrolysis is primarily attributed to the N-H bond breaking in pyrrole at low temperatures.At high temperatures,it is predominantly associated with the hydrogen abstraction reaction between carboxyl functional groups and the dehydrogenation reaction of hydrogen bond breaking in the aliphatic hydrocarbon structures.H2O is primarily attributed to the reaction of the hydroxyl group on the carboxyl group.CO_(2) is always related to the carboxyl group.CO is mainly related to the reduction reaction of carbonyl group,carboxyl group,and CO_(2).During the initial pyrolysis stage of ZD-D after acid demineralization treatment,the hydrogen abstraction reaction of the carboxyl functional group and the generation of CO molecules by the methoxy group are enhanced.The generation of H2 by the aliphatic structure is enhanced in the main pyrolysis stage.The ring-opening reaction of the phenoxy group to generate CO in the polycondensation pyrolysis stage is also facilitated. 展开更多
关键词 coal pyrolysis demineralization coal reaction mechanism ReaxFF md
在线阅读 下载PDF
麦角甾醇过氧化物阻碍LPS介导TLR4/MD-2二聚化抑制炎症信号传递的研究
9
作者 左月月 彭俊超 +1 位作者 易琼 王鲁 《中国免疫学杂志》 北大核心 2026年第2期273-277,共5页
目的:探究麦角甾醇过氧化物(EP)阻碍LPS炎症信号传递的机制。方法:以TLR4/MD-2为靶点,通过分子对接、流式细胞术、激光共聚焦、免疫共沉淀、免疫印迹以及表面等离子共振等手段研究EP与TLR4/MD-2间的作用以及抑制LPS信号传递的方式。结果... 目的:探究麦角甾醇过氧化物(EP)阻碍LPS炎症信号传递的机制。方法:以TLR4/MD-2为靶点,通过分子对接、流式细胞术、激光共聚焦、免疫共沉淀、免疫印迹以及表面等离子共振等手段研究EP与TLR4/MD-2间的作用以及抑制LPS信号传递的方式。结果:EP与TLR4/MD-2的多个氨基酸位点存在范德华力和疏水作用,与TLR4/MD-2的亲和力为11.10 nmol/L,显著减弱LPS与细胞膜的结合(P<0.01),抑制TLR4与MD-2的二聚化(P<0.01),抑制下游信号分子IRAK1磷酸化(P<0.01)。结论:EP与TLR4/MD-2结合强,抑制LPS与细胞膜结合,降低TLR4和MD-2二聚化以及IRAK1磷酸化,从而抑制LPS引起的炎症信号向下游传递,EP是TLR4/MD-2蛋白的潜在抑制剂,将为阐明EP以TLR4/MD-2为靶点发挥抗炎作用提供实验数据。 展开更多
关键词 麦角甾醇过氧化物 靶点 TLR4/md-2 LPS 炎症信号
暂未订购
基于CFD-DPM-MD模拟压裂管汇缓冲弯头的冲蚀磨损行为及作用机理
10
作者 刘云海 郑杜塬 祝效华 《机械工程学报》 北大核心 2026年第1期296-309,共14页
油气开采水力压裂作业中,含砂压裂液在缓冲弯头弯肘处的高速湍流引发严重管壁冲蚀磨损,其复杂机制使得抗冲蚀优化面临挑战。为揭示冲蚀机理,构建了耦合流体力学、离散元与分子动力学的多尺度预测模型(CFD-DPM-MD)。研究发现:缓冲弯头主... 油气开采水力压裂作业中,含砂压裂液在缓冲弯头弯肘处的高速湍流引发严重管壁冲蚀磨损,其复杂机制使得抗冲蚀优化面临挑战。为揭示冲蚀机理,构建了耦合流体力学、离散元与分子动力学的多尺度预测模型(CFD-DPM-MD)。研究发现:缓冲弯头主要冲蚀区域位于相贯线处,其损伤与颗粒滞留无关,而由涡旋诱导的颗粒多角度碰撞主导。微观冲击分析表明,固相颗粒碰撞导致壁面原子应力与动能超限时引发位错爆炸,产生非相变塑性变形及剥落。研究还发现,尽管40°冲蚀角下剪切应变面积最大,但65°冲蚀角形成的特殊形貌导致颗粒-壁面接触面积更大,最终冲蚀程度更严重。因此,提升缓冲弯头使用寿命的有效途径包括应用高抗剪切冲蚀涂层或设计特殊形貌壁面以减轻高冲蚀角度损伤。 展开更多
关键词 液固两相 流体力学仿真 分子动力学仿真 冲蚀磨损
原文传递
Erratum:Data-Driven Prediction of Thermal Conductivity from Short MD Trajectories:A GCN-LSTM Approach [Chin.Phys.Lett.43 020801 (2026)]
11
作者 Shihao Feng Haifeng Chen +2 位作者 Jian Zhang Meng An Gang Zhang 《Chinese Physics Letters》 2026年第3期380-380,共1页
In our recently published paper,[1]a typesetting error occurred during the production process.Figure 1 in the published version was incomplete.The processing of molecular dynamics(MD)simulation data into graph-structu... In our recently published paper,[1]a typesetting error occurred during the production process.Figure 1 in the published version was incomplete.The processing of molecular dynamics(MD)simulation data into graph-structured representations in the left bottom panel of thefigure was inadvertently omitted. 展开更多
关键词 typesetting error production processfigure short md trajectories GCN LSTM molecular dynamics simulation thermal conductivity graph structured representations data driven prediction
原文传递
Molecular Simulations of Dynamic Heterogeneity of Segment Motion and Bond Exchange in Polymer Vitrimers
12
作者 Lang Shuai Jiang-Long Li +4 位作者 Jian-Long Wen Ying-Ying Xu Shui Yu Bo-Yu Ding Yi-Jing Nie 《Chinese Journal of Polymer Science》 2026年第1期242-255,I0017,共15页
Vitrimers belong to a class of polymeric materials capable of bond exchange reactions,showing great promise for environmental protection and sustainable development.However,studies on the coupling mechanism between th... Vitrimers belong to a class of polymeric materials capable of bond exchange reactions,showing great promise for environmental protection and sustainable development.However,studies on the coupling mechanism between the bond exchange kinetics and segmental dynamics near the glass transition temperature(T_(g))remain scarce.Herein,we employed molecular dynamics simulations to investigate the dynamic heterogeneity of the segment motion and bond exchange in vitrimers.The simulation results revealed that the bond exchange energy barrier exerts a much stronger influence on the bond exchange kinetics than on the segmental dynamics.At lower temperatures,slower segmental relaxation further constraind the bond exchange rate.Additionally,increasing the bond exchange energy barrier markedly enhanced the dynamic heterogeneity of segment motion.A close correlation was observed between heterogeneity and bond exchange.This study elucidated the coupling mechanism between bond exchange and segmental dynamics at the molecular scale,thereby providing a theoretical basis for designing vitrimer materials with tunable dynamic properties. 展开更多
关键词 Molecular dynamics simulations Vitrimers dynamic heterogeneity
原文传递
Fluid migration in calcite nanopores under salinity gradients:Insights from molecular dynamics
13
作者 Yi Chen Yan Zhang +1 位作者 Run-Sheng Han Lei Wang 《Acta Geochimica》 2026年第1期185-203,共19页
The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of i... The migration mechanisms of ore-forming fluids have long been a focus in the field of ore deposit studies.Calcite is ubiquitously present in various types of rocks in the lithosphere,and the underlying mechanisms of its influence on fluid migration are of crucial importance.While previous studies have revealed that salinity changes can modulate fluid migration,the underlying mechanisms remain poorly understood.We employ molecular dynamics simulations to elucidate how salinity variations in ore-forming fluids modulate the adsorption onto calcite nanopore walls,thereby revealing the microscopic mechanisms governing ore fluid transport through calcite nano-fractures.The results show that the adsorption energy Eint of the solution on the calcite surface increased from -14,948.84±182.48 kcal/mol to -12,144.08±118.2 kcal/mol as salinity increased,which is conducive to the long-range transport of the fluid in the calcite nanopore. 展开更多
关键词 Fluid transport dynamics Salinity gradient regulation Calcite nanopores Molecular dynamics simulation
在线阅读 下载PDF
Short-chain Length Dependence of Equilibrium Dynamics and Nonlinear Rheology in Unentangled Long-chain/Short-chain Polymer Blends
14
作者 Xiao-Yang Wang Bo Liu +2 位作者 Li-Jia An Zhen-Hua Wang Yu-Yuan Lu 《Chinese Journal of Polymer Science》 2026年第2期525-535,I0016,共12页
The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behav... The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behavior of dispersed long chains.Using molecular dynamics simulations based on the Kremer-Grest model,we systematically explore the N_(S)-dependence of static conformations,equilibrium dynamics,and nonlinear shear responses in unentangled long-chain/short-chain polymer blends.Our results demonstrate a decoupling between the static and dynamic sensitivity to N_(S):while the static chain size,R_g,follows Flory theory with slight swelling at small N_(S) due to incomplete excluded volume screening,the diffusion coefficient,D,and the relaxation time,τ_(0),exhibit a strong,non-monotonic N_(S)-dependence,transitioning from monomeric friction dominance at small N_(S) to collective segmental rearrangement at large N_(S).Additionally,we observe partial decoupling between the viscous and normal stress responses:while the zero-shear viscosity,η,is strongly N_(S)-dependent,the first and second normal stress coefficients,Ψ_(1) and Ψ_(2),collapse onto universal curves when scaled by the dimensionless shear rate,γτ_(0),suggesting a common mechanism of orientation and stretching.Under shear,long chains compress in the vorticity direction λ_(z)~Wi^(-0.2),which reduces collision frequency and contributes to shear thinning,while the scaling of weaker orientation resistance m_(G)~Wi^(0.35)reflects hydrodynamic screening by the short-chain matrix.These findings highlight the limitations of single-chain models and emphasize the necessity of considering N_(S)-dependent matrix dynamics and flow-induced structural changes in understanding the rheology of unentangled polymer blends. 展开更多
关键词 Unentangled polymer blend Nonlinear rheology Equilibrium dynamics Hydrodynamic interaction screening Molecular dynamics simulation
原文传递
SSA*-PDWA:A Hierarchical Path Planning Framework with Enhanced A*Algorithm and Dynamic Window Approach for Mobile Robots
15
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
在线阅读 下载PDF
基于改进VMD的传感器动态标定信号处理的研究
16
作者 杨浩 张军 任宗金 《传感器与微系统》 北大核心 2026年第2期67-70,共4页
对三维力压电传感器进行动态标定时,当激振频率增加,谐波检测信号的幅值下降而噪声增加,影响信号的幅值比和相位差检测精度。为此,提出一种结合灰狼优化(GWO)算法、变分模态分解(VMD)和小波阈值的降噪算法。以最小包络熵作为目标,采用GW... 对三维力压电传感器进行动态标定时,当激振频率增加,谐波检测信号的幅值下降而噪声增加,影响信号的幅值比和相位差检测精度。为此,提出一种结合灰狼优化(GWO)算法、变分模态分解(VMD)和小波阈值的降噪算法。以最小包络熵作为目标,采用GWO算法优化VMD中的模态数量K和惩罚系数α,筛选出关键的本征模态函数(IMF)后,进行小波阈值降噪处理,实现信号重构。仿真和实验结果表明:去噪后信噪比提高至32.35 dB,均方根误差(RMSE)与波形相似度同步改善,显著提高了信号检测的准确性。 展开更多
关键词 动态标定 变分模态分解 灰狼优化算法 相位差检测
在线阅读 下载PDF
Dynamic behavior of steel post/wood panel railway noise barriers under aerodynamic loads induced by high-speed trains
17
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
在线阅读 下载PDF
Dynamic Behaviors of Localized Waves of the(2+1)-Dimensional Yu-Toda-Sasa-Fukuyama Equation
18
作者 SUN Xiaoqing XIA Yarong +1 位作者 YAO Ruoxia WANG Weiqing 《应用数学》 北大核心 2026年第2期624-638,共15页
In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equ... In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equation,but also analyze the dynamical behaviors of nonlinear local wave propagation in shallow water.Firstly,based on the Hirota bilinear approach,one to four-order soliton solutions of the YTSF equation are obtained,and the effects of different parameters on the amplitude,propagation trajectory,and displacement of solitons are investigated.Secondly,using the long wave limit approach,one to three-order lump solutions and various physical quantities of the YTSF equation are derived.It is found that the real and imaginary parts of the parameter pi dominate the propagation trajectory and the shape of lump waves,respectively.Furthermore,we construct the hybrid solution for the YTSF equation,leading to the conclusion that the interaction between lumps and solitons constitutes an elastic collision.To intuitively understand the dynamic behaviors of these solutions,we conduct numerical simulations to present vivid three-dimensional visualizations. 展开更多
关键词 (2+1)-dimensional Yu-Toda-Sasa-Fukuyama equation Hirota bilinear approach Lump solutions dynamic behaviors
在线阅读 下载PDF
A Joint Optimization Model for Device Selection and Power Allocation under Dynamic Uncertain Environments
19
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
在线阅读 下载PDF
由EGRS码构造的量子MDS码
20
作者 吴莲铭 《应用数学进展》 2026年第1期133-141,共9页
本文针对量子纠错领域中量子最大距离可分(MDS)码的构造问题展开研究,量子MDS码是一类达到量子Singleton界的最优码,在量子计算与通信中具有重要应用价值。为了突破现有构造方法在码长和参数灵活性上的限制,本文提出了一种创新性的构造... 本文针对量子纠错领域中量子最大距离可分(MDS)码的构造问题展开研究,量子MDS码是一类达到量子Singleton界的最优码,在量子计算与通信中具有重要应用价值。为了突破现有构造方法在码长和参数灵活性上的限制,本文提出了一种创新性的构造:利用两个已知的埃尔米特(Hermitian)自正交扩展广义里德–所罗门(EGRS)码,通过特定的条件组合,来构造一个新的Hermitian自正交EGRS码。利用这一关键结论,我们获得了若干类新的q元量子MDS码。我们构造的量子MDS码的码长与以往的码有很大不同,且参数灵活。本研究不仅为量子MDS码的构造理论提供了新的思路和工具,也为实际量子信息系统中纠错码的设计提供了更多可能性。 展开更多
关键词 量子mdS码 EGRS码 Hermitian自正交
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部