为贯彻落实《教育强国建设规划纲要(2024—2035年)》中关于“拔尖创新人才培养”的战略要求,针对大学一年级力学与热学实验课程中验证性实验占比高、学生创新能力不足的痛点,本文以桥梁振动实验为例,系统探讨了基于PBL(Problem Based Le...为贯彻落实《教育强国建设规划纲要(2024—2035年)》中关于“拔尖创新人才培养”的战略要求,针对大学一年级力学与热学实验课程中验证性实验占比高、学生创新能力不足的痛点,本文以桥梁振动实验为例,系统探讨了基于PBL(Problem Based Learning)教学模式的数字化实验建设与实践成效。研究并构建“问题导入—分组讨论—实验验证—展示汇报—评价反思—拓展探索”六环节闭环教学流程。学生在实验改进、创新设计等拓展研究中的主动性与解决复杂问题的能力显著增强。研究证明,PBL模式能够有效促进力学与热学实验由“验证”向“探究”转型,为高校物理实验课程培养拔尖创新人才提供了可复制、可推广的范例。展开更多
案例教学法作为一种以实例为基础的教学方法,在人文社科领域已得到广泛应用并取得显著成效,但在理工科骨干基础课程中的应用仍处于探索阶段.本研究以《热学》课程为例,系统探讨Case-Based Learning for Physics(CBLP)教学法在理工科本...案例教学法作为一种以实例为基础的教学方法,在人文社科领域已得到广泛应用并取得显著成效,但在理工科骨干基础课程中的应用仍处于探索阶段.本研究以《热学》课程为例,系统探讨Case-Based Learning for Physics(CBLP)教学法在理工科本科基础课程(以《热学》为例)中的理论基础、实践路径与教学效果.通过设计一系列典型热学案例,在教学过程中引导学生先分析案例、自主探索解决方案,再系统学习相关理论知识,最后回归案例验证与拓展,形成"案例-理论-应用"的完整教学闭环.教学实践表明,CBLP教学法能够有效提升学生的学习主动性、批判性思维和知识应用能力.本研究还进一步分析了CBLP教学法实施过程中面临的挑战及相应的解决策略,为CBLP教学法在理工科基础课程中的推广应用提供了实践依据和理论参考.展开更多
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
We propose a data-driven framework for rapid prediction of thermal conductivity in solids based on shorttime molecular dynamics(MD)simulations.By converting atomic configurations into graph representations,a graph con...We propose a data-driven framework for rapid prediction of thermal conductivity in solids based on shorttime molecular dynamics(MD)simulations.By converting atomic configurations into graph representations,a graph convolutional network(GCN)is used to extract spatial features,which are then processed by a long short-term memory(LSTM)network to capture the temporal evolution of physical properties.The framework is validated using equilibrium MD simulations of germanium at 1000 K across various system sizes.With sizespecific normalization and optimized hyperparameters,the model accurately predicts the converged thermal conductivity,achieving results consistent with experimental data.Notably,the proposed method significantly reduces computational time by up to 800-fold at large system sizes,which demonstrates its potential to accelerate thermal transport simulations in solid-state systems.展开更多
An efficient data-driven numerical framework is developed for transient heat conduction analysis in thin-walled structures.The proposed approach integrates spectral time discretization with neural network approximatio...An efficient data-driven numerical framework is developed for transient heat conduction analysis in thin-walled structures.The proposed approach integrates spectral time discretization with neural network approximation,forming a spectral-integrated neural network(SINN)scheme tailored for problems characterized by long-time evolution.Temporal derivatives are treated through a spectral integration strategy based on orthogonal polynomial expansions,which significantly alleviates stability constraints associated with conventional time-marching schemes.A fully connected neural network is employed to approximate the temperature-related variables,while governing equa-tions and boundary conditions are enforced through a physics-informed loss formulation.Numerical investigations demonstrate that the proposed method maintains high accuracy even when large time steps are adopted,where standard numerical solvers often suffer from instability or excessive computational cost.Moreover,the framework exhibits strong robustness for ultrathin configurations with extreme aspect ratios,achieving relative errors on the order of 10−5 or lower.These results indicate that the SINN framework provides a reliable and efficient alternative for transient thermal analysis of thin-walled structures under challenging computational conditions.展开更多
提出一种用于求解三维非线性热传导问题的深度学习边界元方法DeepBEM(Deep Boundary Element Method)。该方法将经典边界积分方程理论与深度神经网络相结合,通过神经网络对非线性温度场进行整体函数逼近,并以非线性热传导问题的边界-域...提出一种用于求解三维非线性热传导问题的深度学习边界元方法DeepBEM(Deep Boundary Element Method)。该方法将经典边界积分方程理论与深度神经网络相结合,通过神经网络对非线性温度场进行整体函数逼近,并以非线性热传导问题的边界-域积分方程作为物理约束构造训练损失函数,从而实现三维非线性热传导问题的高精度数值求解。与传统边界元法相比,所提方法避免了非线性问题求解过程中反复线性化迭代的需求。同时,相较于传统物理信息神经网络方法(PINNs),规避了高阶空间导数的显式计算,从而降低了数值实现复杂度与计算成本。此外,构建的损失函数仅由边界-域积分方程残差组成,无需对控制偏微分方程与边界条件进行人工加权,从而有效提高了训练过程的稳定性与鲁棒性。数值算例结果表明,该方法在求解三维非线性热传导问题时具有较高的计算精度和良好的数值稳定性,并能够适应不同非线性强度条件,为复杂三维非线性热传导问题的数值模拟提供了一种有效途径。展开更多
We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are ...We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are obtained for both the thermal equation and the one-dimensional thermoelastic system,where the impossibility of localization with respect to time is also established.Then,the space estimates are deduced for the multidimensional thermoelastic problem,which allow to show the exponential decay of the energy.展开更多
Pursuing significant thermal rectification effect with minimal temperature differences is critical for thermal rectifiers.While asymmetric structures enable spectral matching,they inherently limit thermal rectificatio...Pursuing significant thermal rectification effect with minimal temperature differences is critical for thermal rectifiers.While asymmetric structures enable spectral matching,they inherently limit thermal rectification performance.To address this issue,we developed a thermal rectification structure comprising a current-biased graphene-coated silicon carbide(SiC)substrate paired with another graphene-coated SiC substrate separated by a nanoscale vacuum gap.A current-biased graphene sheet generates nonreciprocal effect that actively modulates radiative energy transfer.Our theoretical framework demonstrates that the current-biased graphene achieves a high thermal diode efficiency even under a modest temperature difference.Remarkably,the thermal diode efficiency exceeds 0.8 at a temperature difference of just 100 K(between 300 K and 400 K).These findings highlight the synergistic enhancement from graphene coatings and current biasing,providing a viable strategy for nanoscale thermal management applications.展开更多
摘要为贯彻落实《教育强国建设规划纲要(2024—2035年)》中关于“拔尖创新人才培养”的战略要求,针对大学一年级力学与热学实验课程中验证性实验占比高、学生创新能力不足的痛点,本文以桥梁振动实验为例,系统探讨了基于PBL(Problem Based Learning)教学模式的数字化实验建设与实践成效。研究并构建“问题导入—分组讨论—实验验证—展示汇报—评价反思—拓展探索”六环节闭环教学流程。学生在实验改进、创新设计等拓展研究中的主动性与解决复杂问题的能力显著增强。研究证明,PBL模式能够有效促进力学与热学实验由“验证”向“探究”转型,为高校物理实验课程培养拔尖创新人才提供了可复制、可推广的范例。
摘要案例教学法作为一种以实例为基础的教学方法,在人文社科领域已得到广泛应用并取得显著成效,但在理工科骨干基础课程中的应用仍处于探索阶段.本研究以《热学》课程为例,系统探讨Case-Based Learning for Physics(CBLP)教学法在理工科本科基础课程(以《热学》为例)中的理论基础、实践路径与教学效果.通过设计一系列典型热学案例,在教学过程中引导学生先分析案例、自主探索解决方案,再系统学习相关理论知识,最后回归案例验证与拓展,形成"案例-理论-应用"的完整教学闭环.教学实践表明,CBLP教学法能够有效提升学生的学习主动性、批判性思维和知识应用能力.本研究还进一步分析了CBLP教学法实施过程中面临的挑战及相应的解决策略,为CBLP教学法在理工科基础课程中的推广应用提供了实践依据和理论参考.
摘要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.
基金supported by the National Natural Science Foundation of China(Grant No.52376063)the High Performance Computing Center,Yangtze Delta Region Academy in Jiaxing,Beijing Institute of Technology。
摘要We propose a data-driven framework for rapid prediction of thermal conductivity in solids based on shorttime molecular dynamics(MD)simulations.By converting atomic configurations into graph representations,a graph convolutional network(GCN)is used to extract spatial features,which are then processed by a long short-term memory(LSTM)network to capture the temporal evolution of physical properties.The framework is validated using equilibrium MD simulations of germanium at 1000 K across various system sizes.With sizespecific normalization and optimized hyperparameters,the model accurately predicts the converged thermal conductivity,achieving results consistent with experimental data.Notably,the proposed method significantly reduces computational time by up to 800-fold at large system sizes,which demonstrates its potential to accelerate thermal transport simulations in solid-state systems.
基金supported by the National Natural Science Foundation of China(Nos.12422207 and 12372199).
摘要An efficient data-driven numerical framework is developed for transient heat conduction analysis in thin-walled structures.The proposed approach integrates spectral time discretization with neural network approximation,forming a spectral-integrated neural network(SINN)scheme tailored for problems characterized by long-time evolution.Temporal derivatives are treated through a spectral integration strategy based on orthogonal polynomial expansions,which significantly alleviates stability constraints associated with conventional time-marching schemes.A fully connected neural network is employed to approximate the temperature-related variables,while governing equa-tions and boundary conditions are enforced through a physics-informed loss formulation.Numerical investigations demonstrate that the proposed method maintains high accuracy even when large time steps are adopted,where standard numerical solvers often suffer from instability or excessive computational cost.Moreover,the framework exhibits strong robustness for ultrathin configurations with extreme aspect ratios,achieving relative errors on the order of 10−5 or lower.These results indicate that the SINN framework provides a reliable and efficient alternative for transient thermal analysis of thin-walled structures under challenging computational conditions.
摘要提出一种用于求解三维非线性热传导问题的深度学习边界元方法DeepBEM(Deep Boundary Element Method)。该方法将经典边界积分方程理论与深度神经网络相结合,通过神经网络对非线性温度场进行整体函数逼近,并以非线性热传导问题的边界-域积分方程作为物理约束构造训练损失函数,从而实现三维非线性热传导问题的高精度数值求解。与传统边界元法相比,所提方法避免了非线性问题求解过程中反复线性化迭代的需求。同时,相较于传统物理信息神经网络方法(PINNs),规避了高阶空间导数的显式计算,从而降低了数值实现复杂度与计算成本。此外,构建的损失函数仅由边界-域积分方程残差组成,无需对控制偏微分方程与边界条件进行人工加权,从而有效提高了训练过程的稳定性与鲁棒性。数值算例结果表明,该方法在求解三维非线性热传导问题时具有较高的计算精度和良好的数值稳定性,并能够适应不同非线性强度条件,为复杂三维非线性热传导问题的数值模拟提供了一种有效途径。
基金part of the project“Qualitative and numerical analyses of some thermomechanics problems(ACUANUTER)”(Ref.PID2024-156827NB-I00)。
摘要We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are obtained for both the thermal equation and the one-dimensional thermoelastic system,where the impossibility of localization with respect to time is also established.Then,the space estimates are deduced for the multidimensional thermoelastic problem,which allow to show the exponential decay of the energy.
基金Project supported by the National Natural Science Foundation of China(Grant No.12364008)the Ph.D.Research Startup Foundation of Yan’an University(Grant No.YDBK2019-54)the Yan’an High-level Talent Special Project(Grant No.2019263166)。
摘要Pursuing significant thermal rectification effect with minimal temperature differences is critical for thermal rectifiers.While asymmetric structures enable spectral matching,they inherently limit thermal rectification performance.To address this issue,we developed a thermal rectification structure comprising a current-biased graphene-coated silicon carbide(SiC)substrate paired with another graphene-coated SiC substrate separated by a nanoscale vacuum gap.A current-biased graphene sheet generates nonreciprocal effect that actively modulates radiative energy transfer.Our theoretical framework demonstrates that the current-biased graphene achieves a high thermal diode efficiency even under a modest temperature difference.Remarkably,the thermal diode efficiency exceeds 0.8 at a temperature difference of just 100 K(between 300 K and 400 K).These findings highlight the synergistic enhancement from graphene coatings and current biasing,providing a viable strategy for nanoscale thermal management applications.