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基于SPH-FEM流固耦合作用下多级拦挡坝动力响应分析
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作者 王永胜 龚蕓 祝佳 《灾害学》 北大核心 2026年第1期104-114,共11页
为探明泥石流与多级拦挡结构间的相互作用机制,该文建立了耦合的光滑粒子流体动力学(SPH)和有限元方法(FEM)的数值模型,模拟泥石流浆体与块石的相互耦合过程,分析了格栅-重力坝、格栅-格栅坝和重力-重力坝三种组合坝在泥石流作用下动力... 为探明泥石流与多级拦挡结构间的相互作用机制,该文建立了耦合的光滑粒子流体动力学(SPH)和有限元方法(FEM)的数值模型,模拟泥石流浆体与块石的相互耦合过程,分析了格栅-重力坝、格栅-格栅坝和重力-重力坝三种组合坝在泥石流作用下动力响应,包括泥石流速度、冲击力、坝体支反力和Von Mises应力。结果表明:多级拦挡坝承泥石流冲击力与坝体结构密切相关,格栅坝透水性强、整体荷载小但局部应力集中;重力坝借浆体缓冲层降低局部应力。此外,一级坝支反力普遍高于二级坝,当一级为重力坝时应力剧增,为格栅坝则使荷载分配合理、减小应力差。因此坝体结构特性对荷载分配具有调控作用,为工程实践中优选坝型组合可提供设计参考。 展开更多
关键词 泥石流 SPH-fem耦合 多级拦挡坝 动力响应
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基于SPH-FEM大蒜切茎装置动力学分析及参数优化
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作者 李骅 高涵 +3 位作者 王永健 於海明 傅杰一 郭靳枭 《农业机械学报》 北大核心 2026年第4期192-202,共11页
针对目前大蒜联合收获机切茎装置切削性能较差、切割阻力较大、切割不及时易造成大蒜鳞茎损伤以及夹持输送装置堵塞等问题,基于SPH-FEM耦合算法设计了一种大蒜双圆盘式切茎装置,并进行了动力学分析及参数优化。根据大蒜茎秆的结构、物... 针对目前大蒜联合收获机切茎装置切削性能较差、切割阻力较大、切割不及时易造成大蒜鳞茎损伤以及夹持输送装置堵塞等问题,基于SPH-FEM耦合算法设计了一种大蒜双圆盘式切茎装置,并进行了动力学分析及参数优化。根据大蒜茎秆的结构、物理参数和力学特性参数,确定了大蒜茎秆的材料模型。利用ANSYS/LS-DYNA构建大蒜切割过程仿真模型,通过有限元仿真结果确定最优圆盘刀结构参数,圆盘刀厚度2 mm、圆盘刀刃角15°和圆盘刀重叠量15 mm。运用仿真模型进行单因素仿真试验,确定了大蒜切茎装置的喂入速度、圆盘刀转速、圆盘刀间距的取值范围分别为1.5~2.5 km/h、400~600 r/min、1~3 mm;采用Box-Behnken设计三因素三水平正交组合试验方案,通过台架试验确定各因素水平下圆盘刀最大切割阻力,运用Design-Expert 13对试验结果进行方差和响应面分析,得到大蒜切茎装置实际最佳工作参数,喂入速度为2.1 km/h、圆盘刀转速为560 r/min、圆盘刀间距为1 mm。台架试验结果表明,在最优工作参数下最大切割阻力为7.33 N,误差为7.5%。本文所设计的双圆盘式切茎装置切割阻力小、工作性能稳定,茎秆切割面较为平整,并且在试验过程中无鳞茎损伤,满足大蒜收获茎秆切割要求,可为大蒜联合收获机械的设计提供参考。 展开更多
关键词 大蒜切茎 有限元 SPH-fem耦合算法 双圆盘式切茎装置 参数优化
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A Multi-Objective Deep Reinforcement Learning Algorithm for Computation Offloading in Internet of Vehicles
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作者 Junjun Ren Guoqiang Chen +1 位作者 Zheng-Yi Chai Dong Yuan 《Computers, Materials & Continua》 2026年第1期2111-2136,共26页
Vehicle Edge Computing(VEC)and Cloud Computing(CC)significantly enhance the processing efficiency of delay-sensitive and computation-intensive applications by offloading compute-intensive tasks from resource-constrain... Vehicle Edge Computing(VEC)and Cloud Computing(CC)significantly enhance the processing efficiency of delay-sensitive and computation-intensive applications by offloading compute-intensive tasks from resource-constrained onboard devices to nearby Roadside Unit(RSU),thereby achieving lower delay and energy consumption.However,due to the limited storage capacity and energy budget of RSUs,it is challenging to meet the demands of the highly dynamic Internet of Vehicles(IoV)environment.Therefore,determining reasonable service caching and computation offloading strategies is crucial.To address this,this paper proposes a joint service caching scheme for cloud-edge collaborative IoV computation offloading.By modeling the dynamic optimization problem using Markov Decision Processes(MDP),the scheme jointly optimizes task delay,energy consumption,load balancing,and privacy entropy to achieve better quality of service.Additionally,a dynamic adaptive multi-objective deep reinforcement learning algorithm is proposed.Each Double Deep Q-Network(DDQN)agent obtains rewards for different objectives based on distinct reward functions and dynamically updates the objective weights by learning the value changes between objectives using Radial Basis Function Networks(RBFN),thereby efficiently approximating the Pareto-optimal decisions for multiple objectives.Extensive experiments demonstrate that the proposed algorithm can better coordinate the three-tier computing resources of cloud,edge,and vehicles.Compared to existing algorithms,the proposed method reduces task delay and energy consumption by 10.64%and 5.1%,respectively. 展开更多
关键词 Deep reinforcement learning internet of vehicles multi-objective optimization cloud-edge computing computation offloading service caching
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Multi-Objective Enhanced Cheetah Optimizer for Joint Optimization of Computation Offloading and Task Scheduling in Fog Computing
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作者 Ahmad Zia Nazia Azim +5 位作者 Bekarystankyzy Akbayan Khalid J.Alzahrani Ateeq Ur Rehman Faheem Ullah Khan Nouf Al-Kahtani Hend Khalid Alkahtani 《Computers, Materials & Continua》 2026年第3期1559-1588,共30页
The cloud-fog computing paradigm has emerged as a novel hybrid computing model that integrates computational resources at both fog nodes and cloud servers to address the challenges posed by dynamic and heterogeneous c... The cloud-fog computing paradigm has emerged as a novel hybrid computing model that integrates computational resources at both fog nodes and cloud servers to address the challenges posed by dynamic and heterogeneous computing networks.Finding an optimal computational resource for task offloading and then executing efficiently is a critical issue to achieve a trade-off between energy consumption and transmission delay.In this network,the task processed at fog nodes reduces transmission delay.Still,it increases energy consumption,while routing tasks to the cloud server saves energy at the cost of higher communication delay.Moreover,the order in which offloaded tasks are executed affects the system’s efficiency.For instance,executing lower-priority tasks before higher-priority jobs can disturb the reliability and stability of the system.Therefore,an efficient strategy of optimal computation offloading and task scheduling is required for operational efficacy.In this paper,we introduced a multi-objective and enhanced version of Cheeta Optimizer(CO),namely(MoECO),to jointly optimize the computation offloading and task scheduling in cloud-fog networks to minimize two competing objectives,i.e.,energy consumption and communication delay.MoECO first assigns tasks to the optimal computational nodes and then the allocated tasks are scheduled for processing based on the task priority.The mathematical modelling of CO needs improvement in computation time and convergence speed.Therefore,MoECO is proposed to increase the search capability of agents by controlling the search strategy based on a leader’s location.The adaptive step length operator is adjusted to diversify the solution and thus improves the exploration phase,i.e.,global search strategy.Consequently,this prevents the algorithm from getting trapped in the local optimal solution.Moreover,the interaction factor during the exploitation phase is also adjusted based on the location of the prey instead of the adjacent Cheetah.This increases the exploitation capability of agents,i.e.,local search capability.Furthermore,MoECO employs a multi-objective Pareto-optimal front to simultaneously minimize designated objectives.Comprehensive simulations in MATLAB demonstrate that the proposed algorithm obtains multiple solutions via a Pareto-optimal front and achieves an efficient trade-off between optimization objectives compared to baseline methods. 展开更多
关键词 computation offloading task scheduling cheetah optimizer fog computing optimization resource allocation internet of things
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DRL-Based Cross-Regional Computation Offloading Algorithm
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作者 Lincong Zhang Yuqing Liu +2 位作者 Kefeng Wei Weinan Zhao Bo Qian 《Computers, Materials & Continua》 2026年第1期901-918,共18页
In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network e... In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network environments where rapid response is mandatory for safety-critical applications.In scenarios where edge servers are sparsely deployed,the lack of coordination and information sharing often leads to load imbalance,thereby increasing system latency.Furthermore,in regions without edge server coverage,tasks must be processed locally,which further exacerbates latency issues.To address these challenges,we propose a novel and efficient Deep Reinforcement Learning(DRL)-based approach aimed at minimizing average task latency.The proposed method incorporates three offloading strategies:local computation,direct offloading to the edge server in local region,and device-to-device(D2D)-assisted offloading to edge servers in other regions.We formulate the task offloading process as a complex latency minimization optimization problem.To solve it,we propose an advanced algorithm based on the Dueling Double Deep Q-Network(D3QN)architecture and incorporating the Prioritized Experience Replay(PER)mechanism.Experimental results demonstrate that,compared with existing offloading algorithms,the proposed method significantly reduces average task latency,enhances user experience,and offers an effective strategy for latency optimization in future edge computing systems under dynamic workloads. 展开更多
关键词 Edge computing computational task offloading deep reinforcement learning D3QN device-to-device communication system latency optimization
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Quantum Secure Multiparty Computation:Bridging Privacy,Security,and Scalability in the Post-Quantum Era
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作者 Sghaier Guizani Tehseen Mazhar Habib Hamam 《Computers, Materials & Continua》 2026年第4期1-25,共25页
The advent of quantum computing poses a significant challenge to traditional cryptographic protocols,particularly those used in SecureMultiparty Computation(MPC),a fundamental cryptographic primitive for privacypreser... The advent of quantum computing poses a significant challenge to traditional cryptographic protocols,particularly those used in SecureMultiparty Computation(MPC),a fundamental cryptographic primitive for privacypreserving computation.Classical MPC relies on cryptographic techniques such as homomorphic encryption,secret sharing,and oblivious transfer,which may become vulnerable in the post-quantum era due to the computational power of quantum adversaries.This study presents a review of 140 peer-reviewed articles published between 2000 and 2025 that used different databases like MDPI,IEEE Explore,Springer,and Elsevier,examining the applications,types,and security issues with the solution of Quantum computing in different fields.This review explores the impact of quantum computing on MPC security,assesses emerging quantum-resistant MPC protocols,and examines hybrid classicalquantum approaches aimed at mitigating quantum threats.We analyze the role of Quantum Key Distribution(QKD),post-quantum cryptography(PQC),and quantum homomorphic encryption in securing multiparty computations.Additionally,we discuss the challenges of scalability,computational efficiency,and practical deployment of quantumsecure MPC frameworks in real-world applications such as privacy-preserving AI,secure blockchain transactions,and confidential data analysis.This review provides insights into the future research directions and open challenges in ensuring secure,scalable,and quantum-resistant multiparty computation. 展开更多
关键词 Quantum computing secure multiparty computation(MPC) post-quantum cryptography(PQC) quantum key distribution(QKD) privacy-preserving computation quantum homomorphic encryption quantum network security federated learning blockchain security quantum cryptography
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SPH-FEM耦合的山岭隧道长进尺掏槽爆破研究
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作者 周松樊 孟春阳 管晓明 《低温建筑技术》 2026年第2期127-132,共6页
针对山岭隧道电子雷管进行长进尺爆破振动大、掏槽效果不佳的问题,文中采用SPH-FEM耦合方法建立掏槽爆破三维数值模型,研究单孔0~5 ms延期时间下岩石爆破粒子的抛掷情况,分析岩石破碎效果;研究不同延期时间下掏槽成腔演化历程,揭示延期... 针对山岭隧道电子雷管进行长进尺爆破振动大、掏槽效果不佳的问题,文中采用SPH-FEM耦合方法建立掏槽爆破三维数值模型,研究单孔0~5 ms延期时间下岩石爆破粒子的抛掷情况,分析岩石破碎效果;研究不同延期时间下掏槽成腔演化历程,揭示延期时间对掏槽爆破的影响机理。研究结果表明,掏槽孔同时起爆条件下粒子抛掷数量最多、距离最远;随着单孔延时增加,岩石爆破粒子数逐渐减小;其中单孔延时为1 ms时粒子数减少并不显著,2、3 ms时粒子数迅速衰减,4、5 ms时粒子数量减少趋于平缓;单孔延时为1 ms时掏槽腔面积占比最大,达到31.68%,爆破能量利用率最高,破碎效果最优。经现场试验验证,斜眼掏槽孔采用1 ms单孔延时方案,可同时实现高效破岩与爆破振动控制。研究为山岭隧道电子雷管爆破的合理延期时间的设定提供理论依据。 展开更多
关键词 隧道爆破 电子雷管 延时爆破 岩体破碎 SPH-fem耦合
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CUDA‑based GPU‑only computation for efficient tracking simulation of single and multi‑bunch collective effects
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作者 Keon Hee Kim Eun‑San Kim 《Nuclear Science and Techniques》 2026年第1期61-79,共19页
Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based met... Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based methods,tracking on a single CPU core,or parallelizing the computation across multiple cores via the message passing interface(MPI).Although these approaches work well for single-bunch tracking,scaling them to multiple bunches significantly increases the computational load,which often necessitates the use of a dedicated multi-CPU cluster.To address this challenge,alternative methods leveraging General-Purpose computing on Graphics Processing Units(GPGPU)have been proposed,enabling tracking studies on a standalone desktop personal computer(PC).However,frequent CPU-GPU interactions,including data transfers and synchronization operations during tracking,can introduce communication overheads,potentially reducing the overall effectiveness of GPU-based computations.In this study,we propose a novel approach that eliminates this overhead by performing the entire tracking simulation process exclusively on the GPU,thereby enabling the simultaneous processing of all bunches and their macro-particles.Specifically,we introduce MBTRACK2-CUDA,a Compute Unified Device Architecture(CUDA)ported version of MBTRACK2,which facilitates efficient tracking of single-and multi-bunch collective effects by leveraging the full GPU-resident computation. 展开更多
关键词 Code development GPU computing Collective effects
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High-Dimensional Multi-Objective Computation Offloading for MEC in Serial Isomerism Tasks via Flexible Optimization Framework
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作者 Zheng Yao Puqing Chang 《Computers, Materials & Continua》 2026年第1期1160-1177,共18页
As Internet of Things(IoT)applications expand,Mobile Edge Computing(MEC)has emerged as a promising architecture to overcome the real-time processing limitations of mobile devices.Edge-side computation offloading plays... As Internet of Things(IoT)applications expand,Mobile Edge Computing(MEC)has emerged as a promising architecture to overcome the real-time processing limitations of mobile devices.Edge-side computation offloading plays a pivotal role in MEC performance but remains challenging due to complex task topologies,conflicting objectives,and limited resources.This paper addresses high-dimensional multi-objective offloading for serial heterogeneous tasks in MEC.We jointly consider task heterogeneity,high-dimensional objectives,and flexible resource scheduling,modeling the problem as a Many-objective optimization.To solve it,we propose a flexible framework integrating an improved cooperative co-evolutionary algorithm based on decomposition(MOCC/D)and a flexible scheduling strategy.Experimental results on benchmark functions and simulation scenarios show that the proposed method outperforms existing approaches in both convergence and solution quality. 展开更多
关键词 Edge computing offload serial Isomerism applications many-objective optimization flexible resource scheduling
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Physics-Informed Neural Networks:Current Progress and Challenges in Computational Solid and Structural Mechanics
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作者 Itthidet Thawon Duy Vo +6 位作者 Tinh QuocBui Kanya Rattanamongkhonkun Chakkapong Chamroon Nakorn Tippayawong Yuttana Mona Ramnarong Wanison Pana Suttakul 《Computer Modeling in Engineering & Sciences》 2026年第2期48-86,共39页
Physics-informed neural networks(PINNs)have emerged as a promising class of scientific machine learning techniques that integrate governing physical laws into neural network training.Their ability to enforce different... Physics-informed neural networks(PINNs)have emerged as a promising class of scientific machine learning techniques that integrate governing physical laws into neural network training.Their ability to enforce differential equations,constitutive relations,and boundary conditions within the loss function provides a physically grounded alternative to traditional data-driven models,particularly for solid and structural mechanics,where data are often limited or noisy.This review offers a comprehensive assessment of recent developments in PINNs,combining bibliometric analysis,theoretical foundations,application-oriented insights,and methodological innovations.A biblio-metric survey indicates a rapid increase in publications on PINNs since 2018,with prominent research clusters focused on numerical methods,structural analysis,and forecasting.Building upon this trend,the review consolidates advance-ments across five principal application domains,including forward structural analysis,inverse modeling and parameter identification,structural and topology optimization,assessment of structural integrity,and manufacturing processes.These applications are propelled by substantial methodological advancements,encompassing rigorous enforcement of boundary conditions,modified loss functions,adaptive training,domain decomposition strategies,multi-fidelity and transfer learning approaches,as well as hybrid finite element–PINN integration.These advances address recurring challenges in solid mechanics,such as high-order governing equations,material heterogeneity,complex geometries,localized phenomena,and limited experimental data.Despite remaining challenges in computational cost,scalability,and experimental validation,PINNs are increasingly evolving into specialized,physics-aware tools for practical solid and structural mechanics applications. 展开更多
关键词 Artificial Intelligence physics-informed neural networks computational mechanics bibliometric analysis solid mechanics structural mechanics
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FEM-DEM颗粒介质软体机械手指灵活度与刚度变化研究
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作者 汪键 薛祖武 +1 位作者 袁海洋 陈家贤 《制造技术与机床》 北大核心 2026年第3期74-82,共9页
本研究基于颗粒介质的阻塞相变效应,通过数值模拟探讨了软体机械手指的灵活度与变刚度特性。利用Abaqus软件构建了融合颗粒接触非线性力学与堆积状态演化的有限元-离散元(finite element-discrete element,FEM-DEM)耦合模型,系统模拟了... 本研究基于颗粒介质的阻塞相变效应,通过数值模拟探讨了软体机械手指的灵活度与变刚度特性。利用Abaqus软件构建了融合颗粒接触非线性力学与堆积状态演化的有限元-离散元(finite element-discrete element,FEM-DEM)耦合模型,系统模拟了机械手指在不同颗粒体积分数下的动力学响应。研究结果表明,颗粒体积分数是调控机械手指力学性能的关键参数:当体积分数低于50%时,系统处于超松散堆积状态,刚度增强有限(增幅低于2%);当体积分数处于不同堆积状态阈值内,软体机械手指的可观测性能有着明显差异。其中,体积分数超过临界阈值(约55%)进入随机紧密堆积状态后,机械手指指末端位移显著降低(最高达56.74%),整体刚度呈现非线性跃升,最大增幅可达151.29%,实现了从高灵活度向高刚度状态的转变。揭示了基于颗粒阻塞的变刚度机理,为软体机械手指的结构优化与性能预测提供了理论依据与有效的仿真设计工具。 展开更多
关键词 颗粒阻塞 体积分数 堆积态 灵活度 变刚度 软体机械手指 fem-DEM
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Random State Approach to Quantum Computation of Electronic-Structure Properties
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作者 Yiran Bai Feng Xiong Xueheng Kuang 《Chinese Physics Letters》 2026年第1期89-104,共16页
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v... Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials. 展开更多
关键词 periodic materials random state circuit random state quantum algorithms electronic structure properties density states aperiodic materials quantum algorithms quantum computation
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人工智能与大数据背景下基于FEM模型对新质生产力的研究
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作者 周凤芹 颜研 刘京 《产业科技创新》 2025年第3期73-77,共5页
面对传统增长模式瓶颈,我国急需以技术穿透力重构生产函数。本文以科技生产力、绿色生产力、数字生产力三个维度构建新质生产力指标体系,以我国2010-2023年31个省的经济数据为样本,基于FEM(Fixed Effect Model)模型对GDP赋能新质生产力... 面对传统增长模式瓶颈,我国急需以技术穿透力重构生产函数。本文以科技生产力、绿色生产力、数字生产力三个维度构建新质生产力指标体系,以我国2010-2023年31个省的经济数据为样本,基于FEM(Fixed Effect Model)模型对GDP赋能新质生产力发展进行了实证研究,发现GDP每增长1%可驱动新质生产力指数提升10%,该结论在控制多维效应、调整变量组合及内生性检验中均保持高度稳健性。教育投入与地理区位导致区域间新质生产力赋能效应呈现显著异质性,需通过强化区域协同创新、促进技术外溢来缩小发展鸿沟,实现全域均衡提升。 展开更多
关键词 新质生产力 大数据 创新 GDP fem模型
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地震激励下等横截面无限水库频域和时域响应的FEM-SBFEM计算方法
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作者 李上明 肖世富 《应用数学和力学》 北大核心 2025年第4期425-437,共13页
坝体抗震设计和评估需要准确计算无限水库动力响应.基于比例边界有限元法(scaled boundary finite element method,SBFEM)力学推导技术,推导了顺河向地震激励下等横截面无限水域频域响应计算公式,利用Fourier逆变换建立了时域响应控制方... 坝体抗震设计和评估需要准确计算无限水库动力响应.基于比例边界有限元法(scaled boundary finite element method,SBFEM)力学推导技术,推导了顺河向地震激励下等横截面无限水域频域响应计算公式,利用Fourier逆变换建立了时域响应控制方程,通过线性叠加推导了顺河、横河、竖直三向组合地震激励下的无限水域频域和时域响应的SBFEM计算公式.结合有限元法,建立了无限水库频域和时域响应的FEM-SBFEM耦合方程.分析了地震激励下的二维、三维等横截面无限水库频域、时域响应,数值验证了所建立计算公式的正确性.所发展的FEM-SBFEM公式体系可推广应用于库底库岸具有吸收性的、横截面有任意几何形状的无限水库谐响应及瞬态响应分析. 展开更多
关键词 无限水库 瞬态分析 谐响应分析 比例边界有限元 有限元
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Damping computation of liquid sloshing with small amplitude in rigid container using FEM 被引量:11
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作者 Wei Wang Junfeng Li Tianshu Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第1期93-98,共6页
An FEM (Finite Element Method) based damping estimation method of liquid sloshing with small amplitude in rigid container is proposed. Damping of the sloshing is affected by many factors and some of them are very co... An FEM (Finite Element Method) based damping estimation method of liquid sloshing with small amplitude in rigid container is proposed. Damping of the sloshing is affected by many factors and some of them are very complicated. Therefore, this paper aims to provide an estimation range, instead of computing the exact value of damping. This method will consider the dissipation at wall, in the interior, and at the contaminated free surface. Owing to the complexity of viscous damping at the free surface, damping of two extreme conditions are computed to estimate the range of actual damping. An iterative algorithm is designed to solve a special general eigenvalue problem. Comparing the computation results with experimental results, it is found that most of the experimental results are within the range of the numerical estimation. Therefore, the method is effective in estimating the range of the damping of liquid sloshing with small amplitude in rigid container. 展开更多
关键词 Sloshing Damping fem
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基于VOF-FEM方法考虑内部构件影响的大型液舱晃荡强度研究
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作者 李昊 刘俊 +2 位作者 毛佳寅 黄德海 郭涵慧 《中国造船》 北大核心 2025年第4期148-159,共12页
基于VOF方法,针对某船大型液舱建立了考虑内部构件影响的三维晃荡数值模型,开展水动力载荷计算,与液舱晃荡试验的对比验证了计算方法的有效性。基于PATRAN平台的PCL语言编写工具软件,将时空变化的冲击载荷自动加载到有限元模型,开展了... 基于VOF方法,针对某船大型液舱建立了考虑内部构件影响的三维晃荡数值模型,开展水动力载荷计算,与液舱晃荡试验的对比验证了计算方法的有效性。基于PATRAN平台的PCL语言编写工具软件,将时空变化的冲击载荷自动加载到有限元模型,开展了在不同装载高度和船舶不同运动状态下液舱结构动力响应分析和强度校核。对晃荡载荷的准静态等效方法展开研究,采用载荷时历最大值及载荷包络值两种等效方法进行对比分析。结果表明:在目标船设计工况下,载荷包络值的静力分析应力略大于其他状态下的应力,且比值在1.000~1.064浮动,涵盖了所有危险状态,建议用该方法获得的准静态载荷进行液舱晃荡强度校核。 展开更多
关键词 液舱晃荡 VOF-fem载荷转换 瞬态响应分析 静力分析 强度校核
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基于DEM-FEM耦合的喷丸强化响应面模型构建及工艺参数影响分析
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作者 张洪伟 闫锡超 +1 位作者 高师 陈涛 《机械强度》 北大核心 2025年第3期67-74,共8页
为了模拟喷丸强化过程,实现喷丸强化效果快速预测,基于Abaqus软件采用离散元法-有限元法(Discrete Element Method-Finite Element Method,DEM-FEM)耦合建立随机多丸粒喷丸强化模型,并以TC4钛合金为研究对象,通过喷丸强化试验来验证耦... 为了模拟喷丸强化过程,实现喷丸强化效果快速预测,基于Abaqus软件采用离散元法-有限元法(Discrete Element Method-Finite Element Method,DEM-FEM)耦合建立随机多丸粒喷丸强化模型,并以TC4钛合金为研究对象,通过喷丸强化试验来验证耦合模型的准确性。采用Box-Behnken设计(Box-Behnken Design,BBD)法,针对弹丸大小、喷丸速度和喷丸覆盖率3个工艺参数设计了三因素三水平的喷丸仿真试验方案,采用仿真分析获得表面残余应力值及表面粗糙度值,并通过Design-Expert软件进行数值拟合,最终得到喷丸工艺参数与表面残余应力和表面粗糙度之间的函数模型,采用响应面法分析弹丸大小、喷丸速度、喷丸覆盖率三因素之间的交互作用以及对喷丸强化效果的影响规律。结果表明,响应面预测模型结果与仿真计算结果误差低于5%,所建立的响应面预测模型具有较高的近似精度和可靠性,利用此模型可实现喷丸强化效果的有效预测。 展开更多
关键词 喷丸强化 响应面 离散元-有限元耦合 BOX-BEHNKEN设计
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含铀材料侵彻装甲板FEM/SPH耦合算法模拟研究
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作者 陈佳辰 苏自强 +2 位作者 康晶 廉冰 王彦 《核电子学与探测技术》 北大核心 2025年第6期910-914,共5页
含铀材料侵彻装甲板的过程是一个大变形冲击动力学问题。含铀材料侵彻装甲板后不仅会对水源和土壤造成污染,还会对人体造成持久的伤害。因此,需要关注含铀材料侵彻装甲板后气溶胶的释放和沉降问题。本文基于LS-DYNA软件,使用FEM/SPH耦... 含铀材料侵彻装甲板的过程是一个大变形冲击动力学问题。含铀材料侵彻装甲板后不仅会对水源和土壤造成污染,还会对人体造成持久的伤害。因此,需要关注含铀材料侵彻装甲板后气溶胶的释放和沉降问题。本文基于LS-DYNA软件,使用FEM/SPH耦合算法对含铀材料侵彻装甲板的过程进行数值模拟,讨论了含铀材料与装甲板相互作用机制以及变形失效行为;对FEM/SPH耦合算法和FEM方法的模拟结果进行比较,分析两种方法在高速碰撞问题中的优缺点。结果表明,与FEM方法相比,FEM/SPH耦合算法能形象地模拟出高速侵彻过程中材料的破坏、飞溅等现象,此外,获取了含铀材料侵彻装甲板过程中的气溶胶转化率。 展开更多
关键词 LS-DYNA fem/SPH耦合算法 fem方法
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Computation and Analysis of Propellant and Levitation Forces of a Maglev System Using FEM Coupled to External Circuit Model 被引量:1
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作者 Shiyou Yang Lin Yang Qiang Zhou 《Journal of Electromagnetic Analysis and Applications》 2010年第4期270-275,共6页
This paper studies the propellant and levitation forces of a prototype maglev system where the propellant forces are provided by a linear motor system. For this purpose, the mathematical model and method using finite ... This paper studies the propellant and levitation forces of a prototype maglev system where the propellant forces are provided by a linear motor system. For this purpose, the mathematical model and method using finite element method coupled to external circuit model is developed. The details of the propellant and levitation forces for a prototype maglev system under different operating conditions are investigated, and some directions are given for practical engineering applications. 展开更多
关键词 MAGLEV System PROPELLANT FORCE LEVITATION FORCE Numerical computation Finite Element Method
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耦合SBFEM-FEM的高拱坝系统地震响应分析
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作者 陈灯红 梁羽翔 +2 位作者 刘云辉 张心瀚 胡昊文 《水力发电学报》 北大核心 2025年第4期72-84,共13页
高拱坝的巨大尺寸跨度以及需考虑的不同分区材料属性和坝基地形的复杂性,采用传统有限元法进行精细化建模时存在一定局限性。本文建立了一种耦合SBFEM-FEM高拱坝-地基-库水系统的地震分析数值分析模型。该模型以SBFEM理论为基础,通过蒙... 高拱坝的巨大尺寸跨度以及需考虑的不同分区材料属性和坝基地形的复杂性,采用传统有限元法进行精细化建模时存在一定局限性。本文建立了一种耦合SBFEM-FEM高拱坝-地基-库水系统的地震分析数值分析模型。该模型以SBFEM理论为基础,通过蒙皮单元技术耦合八叉树SBFEM自定义单元与ABAQUS内置单元,将SBFEM半解析和网格灵活的优势与ABAQUS成熟的线性与非线性求解器和前/后处理模块相结合。以XL高拱坝为例,对其进行了地震作用下线弹性、接触非线性与材料非线性动力响应分析。结果表明:本文方法相较于传统有限元法能够有效减少计算所需资源,并且能够准确模拟高拱坝在地震作用下的非线性响应及损伤情况,对大坝以及其他建筑的抗震研究具有一定的借鉴意义。 展开更多
关键词 比例边界有限元 耦合SBfem-fem 接触非线性 非线性动力响应 八叉树网格
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