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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Numerical Simulation of the Welding Deformation of Marine Thin Plates Based on a Temperature Gradient-thermal Strain Method
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作者 Lin Wang Yugang Miao +3 位作者 Zhenjian Zhuo Chunxiang Lin Benshun Zhang Duanfeng Han 《哈尔滨工程大学学报(英文版)》 2026年第1期122-135,共14页
Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The t... Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates. 展开更多
关键词 Marine thin plate Welding deformation Numerical simulation Temperature gradient-thermal strain method Shell element
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LBM-LES模型用于城市街区细颗粒物浓度研究
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作者 高然 叶舟 +3 位作者 杨强 梁艳霞 钱跃竑 李金页 《环境科学与技术》 北大核心 2025年第5期133-141,共9页
掌握颗粒物在实际街区中的扩散过程可为及时采取有效的大气污染防治措施提供有力的理论支撑。该研究创新性地采用基于格子玻尔兹曼方法(LBM)的三维LBM-LES模型,以金华市某街区2022年气象与颗粒物浓度监测数据为基础开展了风场和颗粒物... 掌握颗粒物在实际街区中的扩散过程可为及时采取有效的大气污染防治措施提供有力的理论支撑。该研究创新性地采用基于格子玻尔兹曼方法(LBM)的三维LBM-LES模型,以金华市某街区2022年气象与颗粒物浓度监测数据为基础开展了风场和颗粒物扩散模拟研究。结果表明:不同风向条件下,该街区扩散条件存在显著差异,其中东南偏东风条件下扩散最佳,而东南偏南风下最差,主要受到街区建筑布局和其他气象因素的影响;不同高度处颗粒物浓度随着高度增加而减小,尤其在东南偏东风主导下,20 m高度的街区颗粒物浓度显著低于5 m高度处浓度;通过与实测数据对比,该研究中LBM模型模拟的误差均小于20%,最小误差为6.84%,展示了LBM模型在模拟城市街区细颗粒物浓度的应用中具有较大的实际意义。 展开更多
关键词 PM_(2.5)扩散 细颗粒物 城市街区 格子玻尔兹曼方法
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基于LBM-LES方法风力机流场的数值模拟 被引量:6
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作者 邹森 刘勇 +1 位作者 冯欢欢 赵广 《南昌航空大学学报(自然科学版)》 CAS 2017年第2期20-25,共6页
本文基于先进的结合Lattice Boltzmann Method(LBM)与Large Eddy Simulation(LES)两者优点的LBM-LES方法,对典型的三叶片水平轴风力机自由旋转风轮复杂的湍流流场进行了数值模拟。风力机一般是在风的作用下做绕固定轴非定速旋转运动,传... 本文基于先进的结合Lattice Boltzmann Method(LBM)与Large Eddy Simulation(LES)两者优点的LBM-LES方法,对典型的三叶片水平轴风力机自由旋转风轮复杂的湍流流场进行了数值模拟。风力机一般是在风的作用下做绕固定轴非定速旋转运动,传统的计算流体力学(CFD)方法对其复杂流场的研究存在一定的困难。LBM方法三维粒子速度模型为D3Q27,LES则采用了Wall-Adapting Local-Eddy亚格子模型对湍流进行模拟。数值结果表明:LBM-LES方法能够比较好地捕捉风力机复杂的非定常湍流流场细节及其特征。 展开更多
关键词 lbm-les方法 风力机 流场 数值模拟
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基于LBM-LES方法两栖水翼航行器水动特性分析 被引量:3
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作者 冯欢欢 刘勇 +1 位作者 王琦 邹森 《航空工程进展》 CSCD 2019年第1期102-108,共7页
目前,国内外对于两栖航行器气动/水动特性的研究仍处于探索与发展阶段。结合鱼雷及水翼船的特点,提出一种通过改变外形实现水下、水面航行的新型两栖水翼航行器。基于LBM-LES方法对航行器水动特性进行数值仿真,得到航行器在水下、水面... 目前,国内外对于两栖航行器气动/水动特性的研究仍处于探索与发展阶段。结合鱼雷及水翼船的特点,提出一种通过改变外形实现水下、水面航行的新型两栖水翼航行器。基于LBM-LES方法对航行器水动特性进行数值仿真,得到航行器在水下、水面航行时的升力、阻力曲线。结果表明:在水下航行时,收缩水翼的航行器在较小的迎角范围内阻力较小,适合高速航行;在水面航行时,展开的水翼增大了航行器的升力、减小了阻力;通过改变外形航行器能够满足在水下、水面的航行要求,其外形设计及两栖航行性能还有较大的优化空间。 展开更多
关键词 lbm-les 水翼 数值仿真 水动特性
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基于LBM-LES的航母风场尾流数值模拟研究
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作者 江召兵 王丙 +1 位作者 王亮 任智源 《船舶力学》 北大核心 2025年第2期232-241,共10页
采用格子玻尔兹曼和大涡模拟相结合(LBM-LES)的数值方法,针对未简化的航母模型,模拟不同风速和风向角下的风场尾流。通过分析舰载机理想着舰轨迹上风场的分布特征,发现相同风向角、不同风速条件下,无量纲时均风速沿着舰轨迹具有相近的... 采用格子玻尔兹曼和大涡模拟相结合(LBM-LES)的数值方法,针对未简化的航母模型,模拟不同风速和风向角下的风场尾流。通过分析舰载机理想着舰轨迹上风场的分布特征,发现相同风向角、不同风速条件下,无量纲时均风速沿着舰轨迹具有相近的分布规律和大小,垂向分量呈典型的“雄鸡尾”式分布,下沉气流峰值约为来流速度的10%左右;相同来流速度、不同风向角条件下,左舷风时着舰轨迹受尾流影响范围明显大于右舷风时。此外,左舷风时着舰轨迹上的垂直速度以下沉为主,右舷风时既有下沉气流又有上升气流,但以上升气流为主。 展开更多
关键词 计算流体动力学 玻尔兹曼方法 航母 风场尾流 着舰轨迹
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基于LBM-LES方法前缘多孔翼型流场的数值分析
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作者 冯欢欢 刘勇 +2 位作者 王琦 邹森 赵广 《南昌航空大学学报(自然科学版)》 CAS 2017年第4期28-36,共9页
前缘多孔翼型能够有效降低翼型的气动噪音,但是其对流场特性的影响还需进一步的研究。采用基于Lattice Boltzmann Method(LBM)与Large Eddy Simulation(LES)结合的LBM-LES方法对雷诺数为Re=3.5×10~6下的标准GAW-1翼型与前缘多孔GA... 前缘多孔翼型能够有效降低翼型的气动噪音,但是其对流场特性的影响还需进一步的研究。采用基于Lattice Boltzmann Method(LBM)与Large Eddy Simulation(LES)结合的LBM-LES方法对雷诺数为Re=3.5×10~6下的标准GAW-1翼型与前缘多孔GAW-1翼型进行了数值模拟,分析并比较了不同迎角下的流场结构。其中,粒子速度模型采用D2Q9模型,LES采用动态Smagorinsky亚格子模型对湍流进行模拟。数值分析结果表明:LBM-LES方法可以准确地捕捉非定常高雷诺数下湍流流场的流动分离特征,且数值结果可以很好的与实验值吻合;其中,在迎角低于4°的情况下前缘多孔介质对翼型气动特性影响较小,随迎角的增大其对气动特性的影响增大。 展开更多
关键词 lbm-les方法 多孔介质 数值分析 流场 气动特性
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基于LBM-LES方法翼型纯音噪声数值研究 被引量:4
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作者 冯欢欢 刘勇 +1 位作者 王琦 邹森 《计算力学学报》 EI CAS CSCD 北大核心 2019年第5期678-686,共9页
基于LBM-LES方法,对中低雷诺数下的NACA0012翼型纯音噪声进行了直接计算,研究了不同迎角和雷诺数对纯音噪声的影响。计算结果表明,翼型的声源主要位于翼型的分离区和后缘处,在不同迎角和雷诺数下的声辐射特征均具有偶极子声场的特点;迎... 基于LBM-LES方法,对中低雷诺数下的NACA0012翼型纯音噪声进行了直接计算,研究了不同迎角和雷诺数对纯音噪声的影响。计算结果表明,翼型的声源主要位于翼型的分离区和后缘处,在不同迎角和雷诺数下的声辐射特征均具有偶极子声场的特点;迎角的增大将引起较大的旋涡尺度和湍流强度,吸力面声源区域前移。声压级频谱分析表明,随着迎角的增大,纯音噪声逐渐消失,噪声谱最终呈现宽频特征;随着雷诺数的增大,后缘压力脉动增大。声压级频谱中,主频频率随着雷诺数的增大而增大,且符合Paterson公式的幂律关系。此外,声压级频谱特性随着雷诺数的增大表现出由离散特性向宽频特性转变的趋势。 展开更多
关键词 lbm-les 中低雷诺数 纯音噪声 翼型 直接计算
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基于LBM-LES方法的典型复杂地形作用下风力机尾流数值模拟 被引量:13
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作者 许昌 黄海琴 +3 位作者 施晨 端和平 李根 李林敏 《中国电机工程学报》 EI CSCD 北大核心 2020年第13期4236-4243,共8页
为研究典型复杂地形作用下风力机尾流结构特性,采用了基于格子玻尔兹曼方法和大涡模拟方法的数值模拟方法。为验证计算模型的可靠性,选用3种亚格子湍流模型对MEXICO风力机进行数值计算,发现WALE模型的计算结果更为准确。然后采用WALE模... 为研究典型复杂地形作用下风力机尾流结构特性,采用了基于格子玻尔兹曼方法和大涡模拟方法的数值模拟方法。为验证计算模型的可靠性,选用3种亚格子湍流模型对MEXICO风力机进行数值计算,发现WALE模型的计算结果更为准确。然后采用WALE模型计算分析了不同坡度典型山丘地形作用下2 MW风力机流场结构,同时与平坦地形中的尾流结构对比发现:位于山丘顶部的风力机尾流与山丘背风面的回流区相互作用,尾流旋涡和背风面脱落涡相互掺杂,尾流会在高度方向上沿坡面下移,坡度越小时,尾流的下移与贴面效应越明显。 展开更多
关键词 风力机 格子玻尔兹曼方法 大涡模拟 复杂地形 数值模拟
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基于LBM-LES模拟的离合器摩擦副流致运动效应 被引量:1
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作者 李慎龙 刘树成 +2 位作者 邢庆坤 张静 赖宇阳 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2017年第2期490-497,共8页
为了研究离合器摩擦副流致运动效应,将大涡模拟(LES)的壁面自适应局部涡粘模型引入到介观模型中的二维单相自由面格子Boltzmann方法(LBM)中,建立了压力润滑条件下的润滑油与摩擦元件LBM-LES流固耦合数值模拟体系。通过设定不同润滑油喷... 为了研究离合器摩擦副流致运动效应,将大涡模拟(LES)的壁面自适应局部涡粘模型引入到介观模型中的二维单相自由面格子Boltzmann方法(LBM)中,建立了压力润滑条件下的润滑油与摩擦元件LBM-LES流固耦合数值模拟体系。通过设定不同润滑油喷口与摩擦元件的相对位置,不同的喷油流量以及不同的油温,模拟了摩擦元件在与润滑油相互作用下的轴向运动过程,得到了不同喷油口位置、喷油流量和油温下的摩擦元件轴向运动规律,并根据数值模拟结果提出了一种槽式喷油口,有效抑制了摩擦元件的流致运动效应,为湿式多片离合器性能改进提供了理论依据。 展开更多
关键词 流体传动与控制 湿式离合器 格子Boltzmann法 大涡模拟 摩擦元件流致运动
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations:A Review 被引量:5
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 Structural health monitoring data information modal parameters damage identification AI method
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Study of the Transport Behavior of Multispherical Proppant in Intersecting Fracture Based on Discrete Element Method 被引量:1
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作者 Chengyong Peng JianshuWu +2 位作者 Mao Jiang Biao Yin Yishan Lou 《Energy Engineering》 EI 2025年第1期185-201,共17页
To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fract... To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on conductivity.Using reservoir production parameters and the discrete elementmethod,multispherical proppants were constructed.Additionally,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting fractures.Results indicate that turbulent kinetic energy is an intrinsic factor affecting proppant transport.Moreover,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture conductivity.Compared to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures. 展开更多
关键词 Hydraulic fracturing discrete element method PROPPANT SPHERICITY CFD-DEM
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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage 被引量:1
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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In situ stress inversion using nonlinear stress boundaries achieved by the bubbling method 被引量:1
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作者 Xige Liu Chenchun Huang +3 位作者 Wancheng Zhu Joung Oh Chengguo Zhang Guangyao Si 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1510-1527,共18页
Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this cha... Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this challenge,nonlinear stress boundaries for a numerical model are determined through regression analysis of a series of nonlinear coefficient matrices,which are derived from the bubbling method.Considering the randomness and flexibility of the bubbling method,a parametric study is conducted to determine recommended ranges for these parameters,including the standard deviation(σb)of bubble radii,the non-uniform coefficient matrix number(λ)for nonlinear stress boundaries,and the number(m)and positions of in situ stress measurement points.A model case study provides a reference for the selection of these parameters.Additionally,when the nonlinear in situ stress inversion method is employed,stress distortion inevitably occurs near model boundaries,aligning with the Saint Venant's principle.Two strategies are proposed accordingly:employing a systematic reduction of nonlinear coefficients to achieve high inversion accuracy while minimizing significant stress distortion,and excluding regions with severe stress distortion near the model edges while utilizing the central part of the model for subsequent simulations.These two strategies have been successfully implemented in the nonlinear in situ stress inversion of the Xincheng Gold Mine and have achieved higher inversion accuracy than the linear method.Specifically,the linear and nonlinear inversion methods yield root mean square errors(RMSE)of 4.15 and 3.2,and inversion relative errors(δAve)of 22.08%and 17.55%,respectively.Therefore,the nonlinear inversion method outperforms the traditional multiple linear regression method,even in the presence of a systematic reduction in the nonlinear stress boundaries. 展开更多
关键词 In situ stress field Inversion method The bubbling method Nonlinear stress boundary Multiple linear regression method
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Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates
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作者 Yufeng Xing Ye Yuan Gen Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期329-355,共27页
The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytica... The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well. 展开更多
关键词 Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method
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Improved methods,properties,applications and prospects of microbial induced carbonate precipitation(MICP)treated soil:A review 被引量:2
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作者 Xuanshuo Zhang Hongyu Wang +3 位作者 Ya Wang Jinghui Wang Jing Cao Gang Zhang 《Biogeotechnics》 2025年第1期34-54,共21页
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi... Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications. 展开更多
关键词 Soil improvement Bio-cement MICP Improved methods Field application cases
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一种基于Least Square Method算法的城轨车辆车门动作时间精准判断的研究
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作者 李宏菱 宋华杰 +3 位作者 马仲智 周辉 李晴 陈龙 《时代汽车》 2025年第3期190-192,共3页
为研究城市轨道交通车辆客室车门动作时间精准性,门的动作主要依靠直流无刷电机的驱动,所以门动作判断的根本,是对电机运动状态的判读,门运动过程中由于电机码盘线受杂波干扰,系统无法准确寻找计时点从而影响系统判断门运动时间;建立波... 为研究城市轨道交通车辆客室车门动作时间精准性,门的动作主要依靠直流无刷电机的驱动,所以门动作判断的根本,是对电机运动状态的判读,门运动过程中由于电机码盘线受杂波干扰,系统无法准确寻找计时点从而影响系统判断门运动时间;建立波形矫正模型,利用数学方法校准波形,让MCU找出最佳计时点并处理(误差不超过10ms),采用最小二乘法模型,通过最小化误差的平方和找到一组数据的最佳函数匹配,求得未知的数据,并使得这些求得的数据与实际数据之间误差的平方和为最小,可精准地得到门动作时间。模拟测试结果表明,门动作时间测算误差所示其误差为7.42ms,小于10ms。 展开更多
关键词 城轨车辆 客室车门 电机码盘 Least Square method算法 门动作时间精准
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Research on Bearing Fault Diagnosis Method Based on Deep Learning 被引量:1
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作者 Ting Zheng 《Journal of Electronic Research and Application》 2025年第1期1-6,共6页
Bearing is an indispensable key component in mechanical equipment,and its working state is directly related to the stability and safety of the whole equipment.In recent years,with the rapid development of artificial i... Bearing is an indispensable key component in mechanical equipment,and its working state is directly related to the stability and safety of the whole equipment.In recent years,with the rapid development of artificial intelligence technology,especially the breakthrough of deep learning technology,it provides a new idea for bearing fault diagnosis.Deep learning can automatically learn features from a large amount of data,has a strong nonlinear modeling ability,and can effectively solve the problems existing in traditional methods.Aiming at the key problems in bearing fault diagnosis,this paper studies the fault diagnosis method based on deep learning,which not only provides a new solution for bearing fault diagnosis but also provides a reference for the application of deep learning in other mechanical fault diagnosis fields. 展开更多
关键词 Deep learning Bearing failure Diagnostic methods
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Rendered image denoising method with filtering guided by lighting information 被引量:1
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作者 MA Minghui HU Xiaojuan +2 位作者 ZHANG Ripei CHEN Chunyi YU Haiyang 《Optoelectronics Letters》 2025年第4期242-248,共7页
The visual noise of each light intensity area is different when the image is drawn by Monte Carlo method.However,the existing denoising algorithms have limited denoising performance under complex lighting conditions a... The visual noise of each light intensity area is different when the image is drawn by Monte Carlo method.However,the existing denoising algorithms have limited denoising performance under complex lighting conditions and are easy to lose detailed information.So we propose a rendered image denoising method with filtering guided by lighting information.First,we design an image segmentation algorithm based on lighting information to segment the image into different illumination areas.Then,we establish the parameter prediction model guided by lighting information for filtering(PGLF)to predict the filtering parameters of different illumination areas.For different illumination areas,we use these filtering parameters to construct area filters,and the filters are guided by the lighting information to perform sub-area filtering.Finally,the filtering results are fused with auxiliary features to output denoised images for improving the overall denoising effect of the image.Under the physically based rendering tool(PBRT)scene and Tungsten dataset,the experimental results show that compared with other guided filtering denoising methods,our method improves the peak signal-to-noise ratio(PSNR)metrics by 4.2164 dB on average and the structural similarity index(SSIM)metrics by 7.8%on average.This shows that our method can better reduce the noise in complex lighting scenesand improvethe imagequality. 展开更多
关键词 establish paramet rendered image denoising Monte Carlo method filtering guided lighting information denoising algorithms image segmentation algorithm rendered image denoising method monte carlo methodhoweverthe
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3D slope stability analysis considering strength anisotropy by a microstructure tensor enhanced elasto-plastic finite element method 被引量:1
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作者 Wencheng Wei Hongxiang Tang +1 位作者 Xiaoyu Song Xiangji Ye 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1664-1684,共21页
This article presents a micro-structure tensor enhanced elasto-plastic finite element(FE)method to address strength anisotropy in three-dimensional(3D)soil slope stability analysis.The gravity increase method(GIM)is e... This article presents a micro-structure tensor enhanced elasto-plastic finite element(FE)method to address strength anisotropy in three-dimensional(3D)soil slope stability analysis.The gravity increase method(GIM)is employed to analyze the stability of 3D anisotropic soil slopes.The accuracy of the proposed method is first verified against the data in the literature.We then simulate the 3D soil slope with a straight slope surface and the convex and concave slope surfaces with a 90turning corner to study the 3D effect on slope stability and the failure mechanism under anisotropy conditions.Based on our numerical results,the end effect significantly impacts the failure mechanism and safety factor.Anisotropy degree notably affects the safety factor,with higher degrees leading to deeper landslides.For concave slopes,they can be approximated by straight slopes with suitable boundary conditions to assess their stability.Furthermore,a case study of the Saint-Alban test embankment A in Quebec,Canada,is provided to demonstrate the applicability of the proposed FE model. 展开更多
关键词 Strength anisotropy Elasto-plastic finite element method(FEM) Three-dimensional(3D)soil slope Gravity increase method(GIM) Stability analysis Case study
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