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一种隐式稳定节点光滑有限元分解ALE法及其在大变形分析中的应用
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作者 陈曦 吕彦楠 +3 位作者 于玉贞 崔柳生 许哲 郭菁 《岩土工程学报》 北大核心 2026年第2期250-258,共9页
岩土工程常涉及土体大变形问题,采用基于小变形假设的有限元法对其进行分析会产生较大计算误差或因网格畸变而导致计算中断。分解任意拉格朗日-欧拉(ALE)法将网格变形与材料变形分离,分别执行更新拉格朗日(UL)步与欧拉步以便克服网格畸... 岩土工程常涉及土体大变形问题,采用基于小变形假设的有限元法对其进行分析会产生较大计算误差或因网格畸变而导致计算中断。分解任意拉格朗日-欧拉(ALE)法将网格变形与材料变形分离,分别执行更新拉格朗日(UL)步与欧拉步以便克服网格畸变引起的计算精度降低或计算中断问题。将稳定节点光滑有限元(NsFEMstab)法与ALE法相结合,提出一种新的NsFEMstab-ALE法,并提出一种用于网格自适应调整策略的动态布点法。以刚性基础地基大变形问题为例,对NsFEMstab-ALE进行检验,数值结果表明:①基于网格自适应调整策略的动态布点法能够有效解决大变形引起的网格畸变问题,实现网格疏密平滑过渡,确保大变形模拟过程中整个网格单元具有良好质量;②应用NsFEMstab-ALE法时,能够获得与参考文献相符的荷载-位移响应曲线以及合理的等效塑性应变云图和网格变形图。 展开更多
关键词 土体大变形 稳定节点光滑有限元法 隐式有限元框架 自适应网格重划分 任意拉格朗日-欧拉法
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DDNet:A Novel Dynamic Lightweight Super-Resolution Algorithm for Arbitrary Scales
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作者 Yiqiao Gong Chunlai Wu +4 位作者 Wenfeng Zheng Siyu Lu Guangyu Xu Lijuan Zhang Lirong Yin 《Computer Modeling in Engineering & Sciences》 2025年第11期2223-2252,共30页
Recent Super-Resolution(SR)algorithms often suffer from excessive model complexity,high computational costs,and limited flexibility across varying image scales.To address these challenges,we propose DDNet,a dynamic an... Recent Super-Resolution(SR)algorithms often suffer from excessive model complexity,high computational costs,and limited flexibility across varying image scales.To address these challenges,we propose DDNet,a dynamic and lightweight SR framework designed for arbitrary scaling factors.DDNet integrates a residual learning structure with an Adaptively fusion Feature Block(AFB)and a scale-aware upsampling module,effectively reducing parameter overhead while preserving reconstruction quality.Additionally,we introduce DDNetGAN,an enhanced variant that leverages a relativistic Generative Adversarial Network(GAN)to further improve texture realism.To validate the proposed models,we conduct extensive training using the DIV2K and Flickr2K datasets and evaluate performance across standard benchmarks including Set5,Set14,Urban100,Manga109,and BSD100.Our experiments cover both symmetric and asymmetric upscaling factors and incorporate ablation studies to assess key components.Results show that DDNet and DDNetGAN achieve competitive performance compared with mainstream SR algorithms,demonstrating a strong balance between accuracy,efficiency,and flexibility.These findings highlight the potential of our approach for practical real-world super-resolution applications. 展开更多
关键词 DDNet DDNetGAN fully dynamic LIGHTWEIGHT arbitrary scale super-resolution algorithm
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Modeling and simulation of aerial refueling multi-body system based on ALE-ANCF method
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作者 Haizhen WANG Yang ZHANG +2 位作者 Zhiwei SUN Bailing LIU Zhaobing JIANG 《Chinese Journal of Aeronautics》 2026年第1期263-277,共15页
The hose-drogue system is a common method for soft aerial refueling,whereby the refueling tanker tows the drogue through the hose.In this paper,a mathematical-physical model of the hose-drogue system is developed and ... The hose-drogue system is a common method for soft aerial refueling,whereby the refueling tanker tows the drogue through the hose.In this paper,a mathematical-physical model of the hose-drogue system is developed and simulated using the Absolute Nodal Coordinate Formulation(ANCF)finite element method.A numerical solution program based on ANCF and ALE(Arbitrary Eulerian-Lagrange)-ANCF method was developed to simulate and analyze the horizontal and elongation release processes of the hose-drogue system at different towing points(underneath the wing and the belly of the aircraft).This program was developed by introducing an ALE description.The numerical solution program,developed based on the ANCF and ALE-ANCF methods,represents a significant advancement in computational efficiency for the rigid-flexible coupled multibody system of the air refueling hose-drogue system.This program can provide a valuable reference for the qualitative design of the hose-drogue multibody system in soft air refueling,while maintaining the necessary accuracy. 展开更多
关键词 Absolute Nodal Coordinate Formulation(ANCF) Aerial refueling arbitrary Eulerian-Lagrange(ale) Multibody system Rigid-flexible coupling
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基于ALE方法的自升式平台抗倾覆稳性校核方法
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作者 刘晓磊 王沫 周智楠 《中国舰船研究》 北大核心 2026年第1期122-131,共10页
[目的]在独立桩腿式自升式平台抗倾覆稳性校核中,非线性分析计算成本高、规范方法精度不足。为此,提出一种精准高效计算方法,将其用于工程设计并完善相关校核体系。[方法]以无桩靴自升式平台为研究对象,基于拉格朗日−欧拉方法(ALE)建立... [目的]在独立桩腿式自升式平台抗倾覆稳性校核中,非线性分析计算成本高、规范方法精度不足。为此,提出一种精准高效计算方法,将其用于工程设计并完善相关校核体系。[方法]以无桩靴自升式平台为研究对象,基于拉格朗日−欧拉方法(ALE)建立土壤−桩腿有限元模型,通过在桩腿顶端施加弯矩模拟倾覆力矩,分析桩腿的整体位移、旋转角度及其旋转中心距泥面的相对垂向距离的变化规律;通过改变插桩深度(8~15 m)及土壤参数以验证规律的通用性,并结合平台实例,对比所提方法、中国船级社规范方法与非线性管土分析方法的结果。[结果]研究明确了桩腿运动呈现“整体平动+绕旋转中心转动”的特征。结果表明,在桩腿倾覆过程中其旋转中心距泥面相对垂向距离的离散程度小,可近似为恒定;所提方法的计算结果相比规范方法,其相对误差降低约10%,更接近于非线性分析的准确值。[结论]所提方法兼顾了计算精度与效率,可为自升式平台抗倾覆稳性校核提供可靠的工程参考。 展开更多
关键词 钻井平台 自升式平台 抗倾覆稳性 稳性校核 倾覆力矩 管土相互作用 柱腿 ale方法
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基于附加质量法与ALE法的隔震渡槽地震响应对比研究
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作者 张宇亭 彭银杰 +2 位作者 曲树盛 刘华北 曾凯锋 《水电能源科学》 北大核心 2025年第11期130-133,114,共5页
为了探究隔震渡槽在地震作用下的响应规律,以淠河总干渠隔震渡槽为例,采用附加质量法与ALE法分别对其在不同工况下的地震响应(主要包括隔震系数、渡槽的水平相对位移峰值、主筋最大拉应力及槽墩混凝土最大压应力)进行了有限元模拟研究... 为了探究隔震渡槽在地震作用下的响应规律,以淠河总干渠隔震渡槽为例,采用附加质量法与ALE法分别对其在不同工况下的地震响应(主要包括隔震系数、渡槽的水平相对位移峰值、主筋最大拉应力及槽墩混凝土最大压应力)进行了有限元模拟研究。同时,通过对比附加质量模型与ALE流固耦合模型两种模型中渡槽地震响应的差异,探讨了流固耦合作用在渡槽抗震分析中的关键作用。结果表明,支座的隔震系数随支座摩擦系数的增大整体上呈增大趋势,随地震强度的增加而减小。槽墩混凝土最大压应力及主筋最大拉应力均随支座摩擦系数和地震强度的增大而增大。另外在有水情况下,附加质量模型与ALE流固耦合模型的模拟结果间存在显著的差异,这说明渡槽抗震研究中有必要考虑水体与渡槽间的流固耦合作用。 展开更多
关键词 渡槽 附加质量法 ale 摩擦摆支座 流固耦合分析 地震响应
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基于KCC模型-ALE算法的充填体动力响应数值模拟研究
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作者 王平 景瑞华 +3 位作者 程爱平 郑先伟 李鑫鹏 骆正杰 《化工矿物与加工》 2025年第1期39-48,共10页
胶结充填体作为人工矿柱常受到邻近矿房开采的爆破扰动,严重影响其稳定性。基于KCC(Karagozian and Case Concrete)本构模型和ALE(Arbitrary Lagrangian-Eulerian)流固耦合算法,采用LS-DYNA软件开展胶结充填体受邻近矿房爆破扰动的数值... 胶结充填体作为人工矿柱常受到邻近矿房开采的爆破扰动,严重影响其稳定性。基于KCC(Karagozian and Case Concrete)本构模型和ALE(Arbitrary Lagrangian-Eulerian)流固耦合算法,采用LS-DYNA软件开展胶结充填体受邻近矿房爆破扰动的数值模拟研究,考虑不同边孔间距(0.6、1.2、1.8、2.4 m)及养护龄期(14、21、28 d)影响,揭示充填体中爆破波传播规律,探究爆破扰动对胶结充填体的动力响应及其失稳破坏情况。结果表明:邻近采场爆破对胶结充填体的破坏损伤主要集中在边界处,为提高矿石回收率并保证充填体安全,建议采用边孔间距1.2 m方案;矿山爆破开采中充填体至少需要养护21 d;低龄期充填体矿柱顶底部区域是整个矿柱中的薄弱部分,易发生失稳,应予以重点监测。 展开更多
关键词 胶结充填体 KCC模型 ale流固耦合算法 边孔间距 LS-DYNA 爆破波 数值模拟
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Arbitrary Scale Super Resolution Network for Satellite Imagery 被引量:4
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作者 Jing Fang Jing Xiao +2 位作者 Xu Wang Dan Chen Ruimin Hu 《China Communications》 SCIE CSCD 2022年第8期234-246,共13页
Recently,satellite imagery has been widely applied in many areas.However,due to the limitations of hardware equipment and transmission bandwidth,the images received on the ground have low resolution and weak texture.I... Recently,satellite imagery has been widely applied in many areas.However,due to the limitations of hardware equipment and transmission bandwidth,the images received on the ground have low resolution and weak texture.In addition,since ground terminals have various resolutions and real-time playing requirements,it is essential to achieve arbitrary scale super-resolution(SR)of satellite images.In this paper,we propose an arbitrary scale SR network for satellite image reconstruction.First,we propose an arbitrary upscale module for satellite imagery that can map low-resolution satellite image features to arbitrary scale enlarged SR outputs.Second,we design an edge reinforcement module to enhance the highfrequency details in satellite images through a twobranch network.Finally,extensive upsample experiments on WHU-RS19 and NWPU-RESISC45 datasets and subsequent image segmentation experiments both show the superiority of our method over the counterparts. 展开更多
关键词 satellite imagery super resolution arbitrary upscale edge reinforcement video satellite
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Single-Step Arbitrary Lagrangian-Eulerian Discontinuous Galerkin Method for 1-D Euler Equations
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作者 Jayesh Badwaik Praveen Chandrashekar Christian Klingenberg 《Communications on Applied Mathematics and Computation》 2020年第4期541-579,共39页
We propose an explicit,single-step discontinuous Galerkin method on moving grids using the arbitrary Lagrangian-Eulerian approach for one-dimensional Euler equations.The grid is moved with the local fluid velocity mod... We propose an explicit,single-step discontinuous Galerkin method on moving grids using the arbitrary Lagrangian-Eulerian approach for one-dimensional Euler equations.The grid is moved with the local fluid velocity modified by some smoothing,which is found to con-siderably reduce the numerical dissipation introduced by Riemann solvers.The scheme preserves constant states for any mesh motion and we also study its positivity preservation property.Local grid refinement and coarsening are performed to maintain the mesh qual-ity and avoid the appearance of very small or large cells.Second,higher order methods are developed and several test cases are provided to demonstrate the accuracy of the proposed scheme. 展开更多
关键词 Discontinuous Galerkin method Moving meshes arbitrary Lagrangian-Eulerian Euler equations
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Arbitrary Lagrangian‑Eulerian Discontinuous Galerkin Methods for KdV Type Equations
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作者 Xue Hong Yinhua Xia 《Communications on Applied Mathematics and Computation》 2022年第2期530-562,共33页
In this paper,several arbitrary Lagrangian-Eulerian discontinuous Galerkin(ALE-DG)methods are presented for Korteweg-de Vries(KdV)type equations on moving meshes.Based on the L^(2) conservation law of KdV equations,we... In this paper,several arbitrary Lagrangian-Eulerian discontinuous Galerkin(ALE-DG)methods are presented for Korteweg-de Vries(KdV)type equations on moving meshes.Based on the L^(2) conservation law of KdV equations,we adopt the conservative and dissipative numerical fuxes for the nonlinear convection and linear dispersive terms,respectively.Thus,one conservative and three dissipative ALE-DG schemes are proposed for the equations.The invariant preserving property for the conservative scheme and the corresponding dissipative properties for the other three dissipative schemes are all presented and proved in this paper.In addition,the L^(2)-norm error estimates are also proved for two schemes,whose numerical fuxes for the linear dispersive term are both dissipative type.More precisely,when choosing the approximation space with the piecewise kth degree polynomials,the error estimate provides the kth order of convergence rate in L^(2)-norm for the scheme with the conservative numerical fuxes applied for the nonlinear convection term.Furthermore,the(k+1∕2)th order of accuracy can be proved for the ALE-DG scheme with dissipative numerical fuxes applied for the convection term.Moreover,a Hamiltonian conservative ALE-DG scheme is also presented based on the conservation of the Hamiltonian for KdV equations.Numerical examples are shown to demonstrate the accuracy and capability of the moving mesh ALE-DG methods and compare with stationary DG methods. 展开更多
关键词 arbitrary Lagrangian-Eulerian discontinuous Galerkin methods KdV equations Conservative schemes Dissipative schemes Error estimates
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Negative Norm Estimates for Arbitrary Lagrangian-Eulerian Discontinuous Galerkin Method for Nonlinear Hyperbolic Equations
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作者 Qi Tao Yan Xu Xiaozhou Li 《Communications on Applied Mathematics and Computation》 2022年第1期250-270,共21页
In this paper,we present the negative norm estimates for the arbitrary Lagrangian-Eulerian discontinuous Galerkin(ALE-DG)method solving nonlinear hyperbolic equations with smooth solutions.The smoothness-increasing ac... In this paper,we present the negative norm estimates for the arbitrary Lagrangian-Eulerian discontinuous Galerkin(ALE-DG)method solving nonlinear hyperbolic equations with smooth solutions.The smoothness-increasing accuracy-conserving(SIAC)filter is a post-processing technique to enhance the accuracy of the discontinuous Galerkin(DG)solutions.This work is the essential step to extend the SIAC filter to the moving mesh for nonlinear problems.By the post-processing theory,the negative norm estimates are vital to get the superconvergence error estimates of the solutions after post-processing in the L2 norm.Although the SIAC filter has been extended to nonuniform mesh,the analysis of fil-tered solutions on the nonuniform mesh is complicated.We prove superconvergence error estimates in the negative norm for the ALE-DG method on moving meshes.The main dif-ficulties of the analysis are the terms in the ALE-DG scheme brought by the grid velocity field,and the time-dependent function space.The mapping from time-dependent cells to reference cells is very crucial in the proof.The numerical results also confirm the theoreti-cal proof. 展开更多
关键词 arbitrary Lagrangian-Eulerian discontinuous Galerkin method Nonlinear hyperbolic equations Negative norm estimates Smoothness-increasing accuracy-conserving filter POST-PROCESSING
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基于S-ALE数值水池的水陆两栖飞机滑行水动响应
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作者 魏佳庆 彭相富 +3 位作者 吴彬 江婷 王明振 杨扬 《兵工学报》 北大核心 2025年第5期400-412,共13页
水陆两栖飞机在水面滑行过程中会不可避免地会遭受波浪等复杂海况的水动冲击,严重时可能引起机身结构变形破坏,对机体及机乘人员的安全造成威胁。以国产大型水陆两栖飞机为研究对象,采用结构化任意拉格朗日-欧拉(Structured-Arbitrary L... 水陆两栖飞机在水面滑行过程中会不可避免地会遭受波浪等复杂海况的水动冲击,严重时可能引起机身结构变形破坏,对机体及机乘人员的安全造成威胁。以国产大型水陆两栖飞机为研究对象,采用结构化任意拉格朗日-欧拉(Structured-Arbitrary Lagrangian-Eulerian, S-ALE)方法,研究水陆两栖飞机在波浪水面滑行过程中的水动响应问题。建立基于S-ALE和罚函数接触算法的流固耦合模拟方法,采用仿物理推板式造波模式与质量阻尼消波法模拟生成数值波浪水池,分别对平静水面和波浪水面滑行过程中的飞机水动特性和耐波性进行研究。研究结果表明:S-ALE方法可以有效地模拟水陆两栖飞机在水面滑行的动响应过程;波高1.2 m下飞机以19.4 m/s速度稳定滑行时姿态角为7°,对应的谐振波长为机身长度的2~3倍,谐振波长下飞机姿态变化幅度和升沉运动的剧烈程度会显著高于其他波长;飞机机身与波长比值为1、波高为1.8 m时垂向过载不断变大,1.2 m波高环境下逐渐收敛,波高的变化对纵摇和质心位置升沉规律影响不大。 展开更多
关键词 水陆两栖飞机 数值造波 结构化任意欧拉-拉格朗日方法 耐波性 流固耦合
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基于ALE-ANCF方法的卷曲展开机构动力学建模与分析
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作者 黄斐 袁婷婷 刘锦阳 《振动与冲击》 北大核心 2025年第2期131-142,共12页
针对含复杂的多区域接触的卷曲展开机构,该研究将其简化为带刚性转盘的变长度柔性构件,建立多体系统动力学模型,以实现高效仿真。首先,基于任意拉格朗日-欧拉描述的绝对节点坐标法对变长度梁进行建模;然后,将复杂接触问题简化为移动边... 针对含复杂的多区域接触的卷曲展开机构,该研究将其简化为带刚性转盘的变长度柔性构件,建立多体系统动力学模型,以实现高效仿真。首先,基于任意拉格朗日-欧拉描述的绝对节点坐标法对变长度梁进行建模;然后,将复杂接触问题简化为移动边界的约束关系,给出一种增删节点处理方法,有效解决了单元长度变化引起的奇异和精度问题,在此基础上建立了刚-柔耦合多体系统的动力学模型,用隐式算法实现了动力学方程的数值求解。通过滑绳和动滑轮算例验证了建模方法的有效性;最后,建立了卷曲机构充气展开系统的简化动力学模型,该模型采用任意拉格朗日-欧拉法移动网格实时跟踪卷曲机构的位置,精准捕捉移动边界点,从而高效确定接触行为。分析了气压力与黏附力对展开动力学特性的影响,通过控制黏附力分布,实现了卷曲机构的匀速展开,对工程实际具有参考价值。 展开更多
关键词 变长度梁 任意拉格朗日-欧拉描述的绝对节点坐标法 卷曲展开机构 动力学建模 移动边界约束方程
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Correction to:Arbitrary topological charge vortex beams from carbon dots random lasers
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作者 Xiang-Dong Wang Xiao-Bo Mi +6 位作者 Jiu-Ru He Feng-Ying Ma Jun-Qiao Wang Li Song Yong-Qiang Zhang Si-Yu Lu Yong-Sheng Hu 《Rare Metals》 2025年第5期3592-3592,共1页
In the original publication,incorrect version of Figure 6b has been published.The corrected Figure 6b is provided in this correction.
关键词 figure b CORRECTION vortex beams random lasers carbon dots arbitrary topological charge
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结合ALE与声波团聚的烟气细颗粒物脱除研究
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作者 王也英 张博鹏 韦道明 《环境科学与管理》 2025年第12期78-81,共4页
为提升燃煤电厂烟气细颗粒物脱除效果,结合ALE探析不同参数下声波团聚的烟气细颗粒物脱除率。设计包括由烟气喷口、烟气喷管、烟气换热器、烟气采样的燃煤热态实验装置,设计信号发生器、喇叭、功放及其最优参数。实验中建立基于ALE的声... 为提升燃煤电厂烟气细颗粒物脱除效果,结合ALE探析不同参数下声波团聚的烟气细颗粒物脱除率。设计包括由烟气喷口、烟气喷管、烟气换热器、烟气采样的燃煤热态实验装置,设计信号发生器、喇叭、功放及其最优参数。实验中建立基于ALE的声波团聚模型并进行验证,证明建立的模型能有效描述烟气细颗粒物脱除效果。研究结果表明:针对不同粒径的烟气细颗粒物,声波频率在1400 Hz左右的脱除效果最好;声强为150 dB时是最佳脱除声强,声波传递方向与烟气流动方向的夹角为0°时,脱除效果最好。 展开更多
关键词 ale 声波团聚 细颗粒物 除尘 声波方向
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自我参照处理中信念多样化作用的神经相关性:一项ALE元分析
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作者 林峻宇 《社会科学前沿》 2025年第4期798-810,共13页
关于自我参照处理中信念的作用,已有两种信念类型的提出:以自我为中心的信念和基于他人视角的信念。然而,这两种信念背后的神经机制仍不明确。为了区分与这两类信念相关的脑部过程,本研究采用ALE元分析方法,分析了自我特质判断任务与虚... 关于自我参照处理中信念的作用,已有两种信念类型的提出:以自我为中心的信念和基于他人视角的信念。然而,这两种信念背后的神经机制仍不明确。为了区分与这两类信念相关的脑部过程,本研究采用ALE元分析方法,分析了自我特质判断任务与虚假信念任务的fMRI研究结果。结果表明,与虚假信念任务相比,在自我特质判断任务中,前扣带回(ACC)的活动显著增强。相反,左侧颞顶联合区(lTPJ)和背内侧前额叶皮层(dmPFC)被认为是自我特质判断任务与虚假信念任务共同激活的区域。基于这些结果,我们认为ACC可能在利用自我中心信念进行特质自我判断时发挥作用,即当自我知识中存在特质与稳定行为模式之间的关联时;而左侧TPJ和dmPFC可能在利用基于他人视角的信念进行自我特质判断时发挥作用,当自我中心信念不足以支持自我判断时,个体需要采纳他人视角进行判断。Two types of beliefs in self-referential processing have been proposed: self-centred beliefs and perspective-taking-based beliefs. However, the neural mechanisms underlying these two types of beliefs remain unclear. In order to distinguish the cerebral processes associated with these beliefs, an ALE meta-analysis was conducted by analysing the fMRI findings from self-judgment of trait tasks and false-belief tasks. The results demonstrated that the anterior cingulate gyrus (ACC) exhibited heightened activity during self-judgment of trait tasks in comparison to false-belief tasks. Conversely, the left temporal-parietal junction (lTPJ) and dorsomedial prefrontal cortex (dmPFC) were identified as common regions shared by both self-judgment of trait tasks and false-belief tasks. Based on these results, we thought that the ACC might be involved in the self-judgment of traits by using self-centered beliefs when there are relationships between traits and stable behavioral patterns in the self-knowledge;the left TPJ and the dmPFC might be involved in the self-judgment of traits by using perspective-taking-based beliefs, where individuals should make self-judgment by taking others’ perspectives when the self-centered beliefs do not sufficiently support the self-judgment. 展开更多
关键词 信念 自我参照处理 自我特质判断 虚假信念 ale元分析
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A finite element-based novel approach to undamped vibrational analysis of complex curved beams with arbitrary curvature using explicit interpolation functions
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作者 A.KESHMIRI T.H.MOTTAGHI A.R.MASOODI 《Applied Mathematics and Mechanics(English Edition)》 2025年第11期2177-2198,共22页
Curved beams with complex geometries are vital in numerous engineering applications,where precise vibration analysis is crucial for ensuring safe and effective designs.Traditional finite element methods(FEMs) often st... Curved beams with complex geometries are vital in numerous engineering applications,where precise vibration analysis is crucial for ensuring safe and effective designs.Traditional finite element methods(FEMs) often struggle to accurately represent the dynamic characteristics of these structures due to the limitations in their shape function approximations.To overcome this challenge,the current study introduces an innovative finite element(FE)-based technique for the undamped vibrational analysis of curved beams with arbitrary curvature,employing explicitly derived interpolation functions.Initially,the exact interpolation functions are developed for circular are elements with the force method.These functions facilitate the creation of a highly accurate stiffness matrix,which is validated against the benchmark examples.To accommodate arbitrary curvature,a systematic transformation technique is established to approximate the intricate curves with a series of circular arcs.The numerical findings indicate that increasing the number of arc segments enhances accuracy,approaching the exact solutions.The analysis of free vibrations is conducted for both circular and non-circular beams.Mass matrices are derived using two methods:lumped mass and consistent mass,where the latter is based on the interpolation functions.The effectiveness of the proposed method is confirmed through the comparisons with the existing literature,demonstrating strong agreement.Finally,several practical cases involving beams with diverse curvature profiles are analyzed.Both natural frequencies and mode shapes are determined,providing significant insights into the dynamic behavior of these structures.This research offers a dependable and efficient analytical framework for the vibrational analysis of complex curved beams,with promising implications for structural and mechanical engineering. 展开更多
关键词 arbitrary curvature curved beam interpolation function free vibration mode shape finite element method(FEM)
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Utilizing artificial intelligence as an arbitrary tool in managing difficult COVID-19 cases in critical care medicine
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作者 Lyubomir Chervenkov Dimitrina Georgieva Miteva Tsvetelina Velikova 《World Journal of Critical Care Medicine》 2025年第3期8-15,共8页
This opinion review paper explores the application of artificial intelligence(AI)as a decisive tool in managing complex coronavirus disease 2019(COVID-19)cases within critical care medicine.Available data have shown t... This opinion review paper explores the application of artificial intelligence(AI)as a decisive tool in managing complex coronavirus disease 2019(COVID-19)cases within critical care medicine.Available data have shown that very severe cases required intensive care,most of which required endotracheal intubation and mechanical ventilation to avoid a lethal outcome if possible.The unprecedented challenges posed by the COVID-19 pandemic necessitate innovative approaches to patient care.AI offers significant potential in enhancing diagnostic accuracy,predicting patient outcomes,and optimizing treatment strategies.By analyzing vast amounts of clinical data,AI can support healthcare professionals in making informed decisions,thus improving patient outcomes.We also focus on current technologies,their implementation in critical care settings,and their impact on patient management during the COVID-19 crisis.Future directions for AI integration in critical care are also discussed. 展开更多
关键词 Artificial Intelligence COVID-19 High-resolution computed tomography Computed tomography Diagnosis Treatment Critical care medicine arbitrary
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Arbitrary Positioning Higher-Order Topological Boundary States in Fe Breathing-Kagome Lattices on Ag(111)
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作者 Rui-Ge Yan Zhuo-Xing Zhang +8 位作者 Tong-Zhou Ji Wen-Lin Fan Hao-Tian Li Liang Sun Bing-Feng Miao Gong Chen Rui Wang Bai-Geng Wang Hai-Feng Ding 《Chinese Physics Letters》 2025年第8期242-263,共22页
Higher-order topological insulators,which host topologically protected states at boundaries that are at least two dimensions lower than the bulk,are an emerging class of topological materials.They provide great opport... Higher-order topological insulators,which host topologically protected states at boundaries that are at least two dimensions lower than the bulk,are an emerging class of topological materials.They provide great opportunities for exploring novel topological phenomena and fascinating applications.Utilizing a low-temperature scanning tunneling microscope,we construct breathing-kagome lattices with Fe adatoms on Ag(111)and investigate their electronic properties.We observe the higher-order topological boundary states in the topological phase but not in the trivial one,which is consistent with the theory.These states are found to be robust against the removal of bulk or edge adatoms.Further,we show the arbitrary positioning of these states either at corner,edge,or bulk sites by slightly modifying their neighbors.Our study not only demonstrates the formation and robustness of the electronic higher-order topological boundary states in real atomic systems but also provides a route for controlling their positions. 展开更多
关键词 arbitrary positioning higher order topological boundary states Ag topological materialsthey Fe breathing kagome lattices higher order topological insulators fe adatoms topologically protected states
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基于ALE算法的飞机水上迫降特性研究
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作者 吕晨光 张顺 《机械设计与制造工程》 2025年第4期115-119,共5页
采用任意拉格朗日-欧拉(ALE)算法系统分析MA60飞机水上迫降过程。计算表明:在选定迫降程序下,飞机着水时呈现显著一次抬头现象,而二次抬头现象微弱,与传统水池试验结果一致,表明ALE算法能够精确模拟水上迫降飞机的运动姿态。研究发现,... 采用任意拉格朗日-欧拉(ALE)算法系统分析MA60飞机水上迫降过程。计算表明:在选定迫降程序下,飞机着水时呈现显著一次抬头现象,而二次抬头现象微弱,与传统水池试验结果一致,表明ALE算法能够精确模拟水上迫降飞机的运动姿态。研究发现,除机腹极小区域外,其余部位应力峰值均未超过材料极限强度,满足设计要求,揭示了迫降载荷与结构强度之间的内在联系。与传统水池试验相比,ALE算法不仅能解析飞机着水时的运动机理,还可以精确捕捉非定常流场特征,阐明流固耦合作用机制,并有效评估结构破损与着水姿态。研究表明,该算法能够兼顾运动学、流体动力学及结构强度分析,为MA60飞机结构设计与性能优化提供了重要理论依据和技术支持。 展开更多
关键词 飞机 水上迫降 适航验证 流固耦合 任意拉格朗日-欧拉算法
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挂索机构几何形状对火箭网系回收动力学的影响
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作者 张欢 阚镭 +2 位作者 周立梁 陈彤 宋晓东 《机械工程学报》 北大核心 2026年第1期216-228,共13页
提出了一种基于二维符号距离场(Signed distance filed,SDF)的柔性绳索与轴向拉伸刚体精准高效接触检测方法,用于火箭网系回收系统中挂索机构与拦阻索的摩擦接触动力学计算,分析挂索机构几何形状对回收动力学的影响。利用轴向拉伸型物... 提出了一种基于二维符号距离场(Signed distance filed,SDF)的柔性绳索与轴向拉伸刚体精准高效接触检测方法,用于火箭网系回收系统中挂索机构与拦阻索的摩擦接触动力学计算,分析挂索机构几何形状对回收动力学的影响。利用轴向拉伸型物体的几何特点,将柔性绳索与具有复杂几何形状的轴向拉伸刚体之间的接触检测问题转换为二维问题。由SDF精准表征截面形状,通过离线生成高精度SDF和法线场,在线双三次插值接触参数计算,实现精准高效摩擦接触动力学计算,所提接触检测方法通过圆柱与绳索的接触动力学仿真和试验验证了准确性。针对捕获火箭的拦阻索入钩过程,建立了挂索机构与拦阻索系统多体动力学模型并针对不同的挂索机构几何形状进行了仿真计算,结果表明挂索机构截面几何形状直接影响挂索机构与拦阻索局部摩擦接触细节,特别在触网时刻,大圆角截面形状能有效降低触网冲击作用。 展开更多
关键词 符号距离场 任意拉格朗日欧拉法 挂索机构 摩擦接触 多体系统动力学
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