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Tracking multiple targets in MIMO radar via adaptive asymmetric joint diagonalization with deflation 被引量:3
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作者 ZHANG Zhengyan ZHANG Jianyun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期731-741,共11页
In view of the low performance of adaptive asymmetric joint diagonalization(AAJD), especially its failure in tracking high maneuvering targets, an adaptive asymmetric joint diagonalization with deflation(AAJDd) al... In view of the low performance of adaptive asymmetric joint diagonalization(AAJD), especially its failure in tracking high maneuvering targets, an adaptive asymmetric joint diagonalization with deflation(AAJDd) algorithm is proposed. The AAJDd algorithm improves performance by estimating the direction of departure(DOD) and direction of arrival(DOA) directly, avoiding the reuse of the previous moment information in the AAJD algorithm.On this basis, the idea of sequential estimation of the principal component is introduced to turn the matrix operation into a constant operation, reducing the amount of computation and speeding up the convergence. Meanwhile, the eigenvalue is obtained, which can be used to estimate the number of targets. Then, the estimation of signal parameters via rotational invariance technique(ESPRIT) algorithm is improved to realize the automatic matching and association of DOD and DOA. The simulation results show that the AAJDd algorithm has higher tracking performance than the AAJD algorithm, especially when the high maneuvering target is tracked. The efficiency of the proposed method is verified. 展开更多
关键词 MIMO radar low complexity angles tracking adaptiveasymmetric joint diagonalization with deflation (AAJDd) high ma-neuvering target
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混凝土圈梁及斜抛撑支护体系在基坑加固中的应用
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作者 张泊渠 孙帅杰 +3 位作者 王环宇 李昕楠 罗利恒 雷言 《建筑技术开发》 2026年第1期122-124,共3页
以上海长三角某地块项目基坑支护工程为依据,研究将应用有混凝土圈梁及斜抛撑基坑加固方案与传统斜抛撑加固方案进行了比较。通过现场施工和监测结果显示,混凝土圈梁及斜抛撑支护体系既有效抑制了基坑变形,保障了周边环境,又减少了底板... 以上海长三角某地块项目基坑支护工程为依据,研究将应用有混凝土圈梁及斜抛撑基坑加固方案与传统斜抛撑加固方案进行了比较。通过现场施工和监测结果显示,混凝土圈梁及斜抛撑支护体系既有效抑制了基坑变形,保障了周边环境,又减少了底板施工缝,提高了底板的防水性能,同时还节省了工期,并带来了良好的经济效益,该研究可为工程实践提供理论指导和技术支持。 展开更多
关键词 基坑加固 混凝土圈梁 斜抛撑支护 变形量
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Online blind source separation based on joint diagonalization 被引量:2
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作者 Li Ronghua Zhou Guoxu Yang Zuyuan Xie Shengli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期229-233,共5页
A new algorithm is proposed for joint diagonalization. With a modified objective function, the new algorithm not only excludes trivial and unbalanced solutions successfully, but is also easily optimized. In addition, ... A new algorithm is proposed for joint diagonalization. With a modified objective function, the new algorithm not only excludes trivial and unbalanced solutions successfully, but is also easily optimized. In addition, with the new objective function, the proposed algorithm can work well in online blind source separation (BSS) for the first time, although this family of algorithms is always thought to be valid only in batch-mode BSS by far. Simulations show that it is a very competitive joint diagonalization algorithm. 展开更多
关键词 blind source separation joint diagonalization nonconvex optimization
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THE STRESS SUBSPACE OF HYBRID STRESS ELEMENT AND THE DIAGONALIZATION METHOD FOR FLEXIBILITY MATRIX H 被引量:2
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作者 张灿辉 冯伟 黄黔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第11期1263-1273,共11页
The following is proved: 1) The linear independence of assumed stress modes is the necessary and sufficient condition for the nonsingular flexibility matrix; 2) The equivalent assumed stress modes lead to the identica... The following is proved: 1) The linear independence of assumed stress modes is the necessary and sufficient condition for the nonsingular flexibility matrix; 2) The equivalent assumed stress modes lead to the identical hybrid element. The Hilbert stress subspace of the assumed stress modes is established. So, it is easy to derive the equivalent orthogonal normal stress modes by Schmidt's method. Because of the resulting diagonal flexibility matrix, the identical hybrid element is free from the complex matrix inversion so that the hybrid efficiency, is improved greatly. The numerical examples show that the method is effective. 展开更多
关键词 hybrid stress finite element Hilbert stress subspace diagonalization method for flexibility matrix
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BCS Ground State and XXZ Antiferromagnetic Model as SU(2),SU(1,1) Coherent States:AN Algebraic Diagonalization Method 被引量:2
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作者 XIEBing_Hao ZHANGHong-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期292-296,共5页
An algebraic diagonalization method is proposed. As two examples, the Hamiltonians of BCS ground stateunder mean-field approximation and XXZ antiferromagnetic model in linear spin-wave frame have been diagonalized byu... An algebraic diagonalization method is proposed. As two examples, the Hamiltonians of BCS ground stateunder mean-field approximation and XXZ antiferromagnetic model in linear spin-wave frame have been diagonalized byusing SU(2), SU(1,1) Lie algebraic method, respectively. Meanwhile, the eigenstates of the above two models are revealedto be SU(2), SU(1,1) coherent states, respectively. The relation between the usual Bogoliubov Valatin transformationand the algebraic method in a special case is also discussed. 展开更多
关键词 algebraic diagonalization method coherent state
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GH-CONGRUENCE CANONICAL FORM OF QUATERNION MATRIX AND SIMULTANEOUS DIAGONALIZATION OF MATRICES 被引量:1
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作者 Zhang Jinchuan(Dept.of Math.,Quanzhou Normal college,Quanzhou,Fujian,362000) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期122-128,共7页
In this paper,the GH-congruence canonical forms of positive semidefinite and definte inite and definite(need not be self-conjugate)quaternion matrices are given,and a neccessary and sufficientcondition of GH-congruenc... In this paper,the GH-congruence canonical forms of positive semidefinite and definte inite and definite(need not be self-conjugate)quaternion matrices are given,and a neccessary and sufficientcondition of GH-congruence for two positive semidifinite(definite)quaternion matrices isgiven also.Then simultaneous GH-congruence reduced forms for two self-conjugate matri-ces and some result about the simultaneous GH-congruence diagonalization of quaternionmatrices are obtained. 展开更多
关键词 GH-CONGRUENCE CANONICAL FORM OF QUATERNION MATRIX AND SIMULTANEOUS diagonalization OF MATRICES REAL EGL PBP FORM
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BCS Ground State and XXZ Antiferromagnetic Model as SU(2), SU(1,1) Coherent States: An Algebraic Diagonalization Method
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作者 XIE Bing-Hao ZHANG Hong-Biao CHEN Jing-Ling 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第9期292-296,共5页
An algebraic diagonalization method is proposed. As two examples, the Hamiltonians of BCS ground stateunder mean-field approximation and XXZ antiferromagnetic model in linear spin-wave frame have been diagonalized byu... An algebraic diagonalization method is proposed. As two examples, the Hamiltonians of BCS ground stateunder mean-field approximation and XXZ antiferromagnetic model in linear spin-wave frame have been diagonalized byusing SU(2), SU(1,1) Lie algebraic method, respectively. Meanwhile, the eigenstates of the above two models are revealedto be SU(2), SU(1,1) coherent states, respectively. The relation between the usual Bogoliubov Valatin transformationand the algebraic method in a special case is also discussed. 展开更多
关键词 ALGEBRAIC diagonalization method coherent state
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GENERALIZED DIAGONALIZATION OF MATRICES OVER QUATERNION FIELD
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作者 姜同松 陈丽 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第11期1297-1304,共8页
A concept of [GRAPHICS] diagonalization matrix over quaternion field is given, the necessary and sufficient conditions for determining whether a quaternion matrix is a [GRAPHICS] diagonalization one are discussed, and... A concept of [GRAPHICS] diagonalization matrix over quaternion field is given, the necessary and sufficient conditions for determining whether a quaternion matrix is a [GRAPHICS] diagonalization one are discussed, and a method of [GRAPHICS] diagonalization of matrices over quaternion field is given. 展开更多
关键词 complex quaternion ring quaternion field MATRIX diagonalization matrix
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Joint User and Antenna Selection for Multiuser MIMO Downlink with Block Diagonalization
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作者 刘伟 邹俊 +1 位作者 罗汉文 马继鹏 《Journal of Shanghai Jiaotong university(Science)》 EI 2011年第6期691-695,共5页
User selection is necessary for multiuser multiple-input multiple-output(MIMO) downlink systems with block diagonalization(BD) due to the limited free spatial transmit dimensions.The pure user selection algorithms can... User selection is necessary for multiuser multiple-input multiple-output(MIMO) downlink systems with block diagonalization(BD) due to the limited free spatial transmit dimensions.The pure user selection algorithms can be improved by performing receive antenna selection(RAS) to increase sum rate.In this paper,a joint user and antenna selection algorithm,which performs user selection for sum rate maximization in the first stage and then performs antenna selection in the second stage,is proposed.The antenna selection process alternately drops one antenna with the poorest channel quality based on maximum determinant ranking(MDR) from the users selected during the first stage and activates one antenna with the maximum norm of projected channel from the remaining users.Simulation results show that the proposed algorithm significantly outperforms the algorithm only performing user selection as well as the algorithm combining user selection with MDR receive antenna selection in terms of sum rate. 展开更多
关键词 MULTIUSER multiple-input multiple-output(MIMO) MULTI-ANTENNA block diagonalization(BD) joint user and antenna selection
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Performance of Block Diagonalization Scheme for Downlink Multiuser MIMO System with Estimated Channel State Information
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作者 Feng Wang Marek E. Bialkowski 《International Journal of Communications, Network and System Sciences》 2011年第2期82-87,共6页
In this paper, we study the performance of block diagonalization (BD) scheme for a downlink multiuser multi-input multi-output (MIMO) system with imperfect channel state information (CSI). At each mobile user, informa... In this paper, we study the performance of block diagonalization (BD) scheme for a downlink multiuser multi-input multi-output (MIMO) system with imperfect channel state information (CSI). At each mobile user, information about the channel is obtained by applying the minimum mean-square-error (MMSE) channel estimation method. The channel state information is fed back to the base station through error-free uplink channels. A theoretical analysis is performed showing that channel estimation errors contribute to co-channel interferences thus deteriorating sum rate capacity. Computer simulations are performed to evaluate the impact of channel estimation errors on the sum rate capacity. The results show that if the MSE of the channel estimation is not less than 10-2, the impact of channel estimation errors is significant and cannot be neglected. To combat this adverse effect, a proper transmit power level is required for the training signals. 展开更多
关键词 MIMO BLOCK diagonalization SUM RATE
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DIAGONALIZATION METHOD FOR A SINGULARLY PERTURBED VECTOR ROBIN PROBLEM
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作者 倪守平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第4期329-336,共8页
In this paper the method and technique of the diagonalization are employed to transform a vector second-order nonlinear system into two first-order approximate diagonalized systems. The existence and the asymptotic be... In this paper the method and technique of the diagonalization are employed to transform a vector second-order nonlinear system into two first-order approximate diagonalized systems. The existence and the asymptotic behavior of the solutions are obtained for a vector second-order nonlinear Robin problem of singular perturbation type. 展开更多
关键词 diagonalization METHOD FOR A SINGULARLY PERTURBED VECTOR ROBIN PROBLEM
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Estimation of 2-D Angles of Arrival Based on Joint Diagonalization of Two Spatio-Temporal Correlation Matrices
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作者 Tie-Qi Xia Xue-Gang Wang Qun Wan Ling Wang 《Journal of Electronic Science and Technology of China》 2007年第3期243-247,共5页
In this paper, we propose a two-dimensional (2-D) angles of arrival (AOAs) estimation method based on a joint diagonalization of two spatio-temporal (ST) correlation matrices. The mathematical manipulations prop... In this paper, we propose a two-dimensional (2-D) angles of arrival (AOAs) estimation method based on a joint diagonalization of two spatio-temporal (ST) correlation matrices. The mathematical manipulations proposed in this paper take the structure of the array that enable estimating 2-D AOAs simultaneously without 2-D searching or pairing. The performance comparison shows that the proposed method is better than ST-DOA matrix method. 展开更多
关键词 2-D angles of arrival joint diagonalization pair matching spatio-temporai.
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面向油气开发的保幅道集生成方法及其应用
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作者 赵忠华 王成 +3 位作者 初海红 张芝铭 晏丰 刘浩宇 《大庆石油地质与开发》 北大核心 2025年第5期36-44,共9页
受实际地震采集条件、地层吸收衰减、偏移算法及计算量等因素影响,偏移后成像道集常出现分辨率低、振幅相对关系不准确等问题。为了解决上述偏移道集的不足,提出了成像域最小二乘照明补偿方法,通过对海森矩阵作“对角化”近似,建立高效... 受实际地震采集条件、地层吸收衰减、偏移算法及计算量等因素影响,偏移后成像道集常出现分辨率低、振幅相对关系不准确等问题。为了解决上述偏移道集的不足,提出了成像域最小二乘照明补偿方法,通过对海森矩阵作“对角化”近似,建立高效对角元计算方法,大幅降低存储及计算量,同时通过引入照明子波,更准确地考虑偏移累加过程,从而直接生成叠前保幅角道集,实现真振幅成像。新方法既考虑了地震波实际传播路径对振幅值的影响,又降低了成像过程中巨大的计算量和存储,实现高效输出,从而得到高保真的角道集和地震成像。应用实例表明:新方法可有效提高叠前道集AVO(振幅随偏移距变化)特征的保幅性,目标层道集AVO特征与正演道集趋势高度一致;与以往成果相比,高保真道集频带平均展宽10 Hz以上,井震匹配相关系数从72%提升至78%。研究成果为叠前反演及储层预测提供了高保真的数据支撑。 展开更多
关键词 海森矩阵 对角化 最小二乘 照明补偿 角道集
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同步密封壳内外壁圆环凹槽复合脱模机构注塑模设计 被引量:2
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作者 张利华 《中国塑料》 北大核心 2025年第2期94-99,共6页
为同步密封壳塑件的注塑成型创新设计了一副多板式一模两腔潜伏式浇口两板模,采用分区分步进行脱模来实现塑件的自动化注塑生产。具体做法为:现将内壁的整圈圆环凹槽分解成4段,其中2段使用内收滑块实施抽芯脱模,剩余2段则使用2个“瓦片... 为同步密封壳塑件的注塑成型创新设计了一副多板式一模两腔潜伏式浇口两板模,采用分区分步进行脱模来实现塑件的自动化注塑生产。具体做法为:现将内壁的整圈圆环凹槽分解成4段,其中2段使用内收滑块实施抽芯脱模,剩余2段则使用2个“瓦片”形斜顶实施侧抽芯脱模,而外壁上的半圆环凹槽则使用2个定模侧哈夫滑块实施侧抽芯脱模,塑件最终由推板推出脱模。塑件的完全脱模由模具的5个动作来实现,包括3次开模动作和2次推出动作,其中第3次开模与2次顶出为同步动作。第1次开模使内收滑块实现内壁圆环凹槽的部分脱模,紧接着使外壁的哈夫滑块完成侧抽芯脱模,第2次为塑件从型腔镶件中脱出,第3次开模动作中,同时也包含2次顶出机构的2次顶出动作。第1次顶出为内壁剩余圆环凹槽使用2次顶出机构的1次顶出板推动斜顶顶出而实现,第2次为上推板将塑件从芯部成型件上推出而实现完全脱模。 展开更多
关键词 同步密封壳 外壁圆环凹槽 内壁圆环凹槽 哈夫滑块 内收滑块 斜顶 二次顶出
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非奇异H-矩阵的几个判定准则
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作者 张劲松 《安徽大学学报(自然科学版)》 北大核心 2025年第3期8-13,共6页
研究了非奇异H-矩阵的判定准则问题.根据广义严格对角占优矩阵和非奇异H-矩阵的等价性,以及α-对角占优矩阵的性质,通过引进适当的参数α,重新划分矩阵的非对角占优行集合,并构造与之对应的正对角因子,得到了非奇异H-矩阵的几个新的判... 研究了非奇异H-矩阵的判定准则问题.根据广义严格对角占优矩阵和非奇异H-矩阵的等价性,以及α-对角占优矩阵的性质,通过引进适当的参数α,重新划分矩阵的非对角占优行集合,并构造与之对应的正对角因子,得到了非奇异H-矩阵的几个新的判定准则.数值算例表明新准则改进了已有的一些结果,扩大了判别范围. 展开更多
关键词 广义严格对角占优 α-对角占优 非奇异H-矩阵 不可约 非零元素链
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基于编码和错位叠加的高速压缩成像
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作者 程涛 涂鑫 李晓妮 《探测与控制学报》 北大核心 2025年第4期182-187,共6页
尽管高速相机和条纹相机的帧速率很高,但是依然无法满足工业和科研日益增长的需求。提出使用毛玻璃对目标图像逐帧编码,然后通过硬件或软件将编码后的图像帧错位叠加,从而极大提高数据压缩比和帧速率。基于逐帧编码和错位叠加后的图像... 尽管高速相机和条纹相机的帧速率很高,但是依然无法满足工业和科研日益增长的需求。提出使用毛玻璃对目标图像逐帧编码,然后通过硬件或软件将编码后的图像帧错位叠加,从而极大提高数据压缩比和帧速率。基于逐帧编码和错位叠加后的图像分别构建错位循环子块矩阵、分块对角矩阵和压缩感知模型。在不改变数据采集模式的基础上,通过优化处理分块对角矩阵和测量数据,进一步改善了解码重构效果。实验结果表明:优化后,即使压缩比为3.33时,也可实现0.54的SSIM和13.98 dB的SNR;当压缩比为2时,就可获得很好的重构效果。SNR不能完全反映图像质量的改善,SSIM是比SNR更好的客观评价指标。 展开更多
关键词 压缩感知 毛玻璃 高速摄影 分块对角矩阵 全变分
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非厄米哈密顿量的厄米理论分析
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作者 张莲莲 范璐宁 +1 位作者 江翠 李家锐 《大学物理》 2025年第4期39-43,共5页
本文在量子力学教学改革探索与实践中加入了非厄米部分的讨论,将非互易哈密顿量的矩阵拆解为厄米哈密顿量和非互易微扰两部分,利用非简并微扰方法求解了能量本征值和本征态,发现所得结果与直接将非互易哈密顿量对角化后做展开的结果完... 本文在量子力学教学改革探索与实践中加入了非厄米部分的讨论,将非互易哈密顿量的矩阵拆解为厄米哈密顿量和非互易微扰两部分,利用非简并微扰方法求解了能量本征值和本征态,发现所得结果与直接将非互易哈密顿量对角化后做展开的结果完全一致.这说明非互易哈密顿量与厄米量子理论存在一定联系.相信本文结果有助于进一步理解非互易哈密顿量的物理性质. 展开更多
关键词 非互易 哈密顿量 对角化 非简并微扰
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基于自动权重的主动块对角子空间聚类
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作者 李向利 谢腾翅 韦嘉逢 《吉林大学学报(理学版)》 北大核心 2025年第6期1673-1684,共12页
针对传统基于谱聚类的子空间聚类方法在高维数据存在离群点时,易受离群点干扰而导致聚类性能下降的问题,提出一种基于自动权重的主动块对角子空间聚类方法.该方法先为每个数据点赋予相应权重,通过权重差异识别数据中的离群点.在确定离... 针对传统基于谱聚类的子空间聚类方法在高维数据存在离群点时,易受离群点干扰而导致聚类性能下降的问题,提出一种基于自动权重的主动块对角子空间聚类方法.该方法先为每个数据点赋予相应权重,通过权重差异识别数据中的离群点.在确定离群点后,主动降低其在表示矩阵中的贡献度,进而构建更优的表示矩阵以提升模型的聚类性能.在10个数据集上与8种对比算法的实验结果表明:在含10%,20%离群点的数据集上,该方法的平均聚类准确率、归一化互信息、调整Rand指数等指标普遍优于对比算法;在一般聚类任务中,其在超过半数数据集上性能最优或位居前三.因此该方法既能高效处理含离群点的高维数据聚类,又能在通用聚类任务中保持竞争力,为提高高维数据聚类的鲁棒性提供了有效方案,有较高的实际应用价值. 展开更多
关键词 子空间聚类 离群点 自动权重 块对角方法
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含改进LuGre摩擦的斜楔减振器斜碰撞动力学分析
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作者 张艳龙 张睿 《噪声与振动控制》 北大核心 2025年第1期27-33,共7页
针对货车转向架用斜楔摩擦减振器,引入改进LuGre动摩擦,通过简化得到一类含动摩擦及间隙的3自由度斜碰撞振动系统,建立系统的力学模型,得到系统的运动方程,并分析系统的运动状态及其条件。通过数值仿真分析外激励频率变化时系统运动的... 针对货车转向架用斜楔摩擦减振器,引入改进LuGre动摩擦,通过简化得到一类含动摩擦及间隙的3自由度斜碰撞振动系统,建立系统的力学模型,得到系统的运动方程,并分析系统的运动状态及其条件。通过数值仿真分析外激励频率变化时系统运动的转迁过程以及黏滞、颤振现象。结果表明:在一定参数下,随着激振频率的变化,系统发生周期倍化分岔、逆周期倍化分岔以及Neimark-Sacher分岔,系统运动存在“周期泡”现象。当系统激振频率在4.4至4.6之间时,系统运动中存在颤振和黏滞现象;当系统激振频率在4.6至5.9之间时,黏滞现象消失,只存在颤振现象。 展开更多
关键词 振动与波 斜楔减振器 斜碰撞 动摩擦 分岔 黏滞 颤振
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微小型驻波超声电机输出性能的对比试验研究
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作者 陈建毅 林星陵 +2 位作者 吴庆勇 郑祝堂 蒋丽省 《机械制造与自动化》 2025年第4期279-283,共5页
为研制直径10 mm的斜齿式和斜槽式两种微小型驻波超声电机样机,利用ANSYS建立定子模型,模拟分析两种样机的工作振动模态,获得谐振频率值,设计并制作两台电机样机,搭建电机样机的试验平台,开展不同驱动频率、驱动电压、预压力等条件下的... 为研制直径10 mm的斜齿式和斜槽式两种微小型驻波超声电机样机,利用ANSYS建立定子模型,模拟分析两种样机的工作振动模态,获得谐振频率值,设计并制作两台电机样机,搭建电机样机的试验平台,开展不同驱动频率、驱动电压、预压力等条件下的输出性能实验研究,分析两种不同定子结构对样机输出转速特性的影响。实验结果表明:在输出转速方面,斜齿式样机要明显高于斜槽式样机。在谐振频率状态、驱动电压170 V和预压力0.065 N试验条件下,斜齿式样机的最大输出转速可达278 r/min,斜槽式样机的最大输出转速为118.5 r/min。 展开更多
关键词 超声电机 驻波 斜齿式 斜槽式 仿真分析 输出性能
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