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关于Rayleigh商矩阵近似特征值估计
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作者 董李娜 王嫣 《华南师范大学学报(自然科学版)》 CAS 北大核心 2012年第3期22-24,共3页
借助于谱分解定理以及矩阵理论中的特征值的排序、优于等相关性质定理研究Hermite矩阵近似特征向量与相应的Rayleigh商矩阵作为近似特征值之间的关系,进行特征值的扰动分析,并推广了一个应用广泛的结论.
关键词 HERMITE矩阵 Rayleigh商矩阵 近似特征值 近似特征向量
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结构参数大修改时的特征值重分析方法 被引量:5
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作者 杨晓伟 陈塑寰 《力学学报》 EI CSCD 北大核心 2001年第4期555-560,共6页
就结构参数发生大修改的情况提出了两种高精度的特征值重分析方法:Pade 逼近法和推广的Kirsch混合法.利用这两种方法,计算了一个具有202个结点,357个梁单元的平面框架的近似特征值.计算结果表明,所提出的方法是... 就结构参数发生大修改的情况提出了两种高精度的特征值重分析方法:Pade 逼近法和推广的Kirsch混合法.利用这两种方法,计算了一个具有202个结点,357个梁单元的平面框架的近似特征值.计算结果表明,所提出的方法是结构参数修改时的特征值重分析的有效方法. 展开更多
关键词 结构参数大修改 特征值重分析 Padé逼近法 Kirsch混合法 平面框架 结构优化 近似特征值
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色噪声背景下基于近似Karhunen-Loève的确知信号检测
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作者 郭世杰 李莉 杨友生 《信息技术》 2004年第12期29-32,共4页
应用一种有效的近似数值方法对确知信号的似然比进行了推导,并对其检测性能进行了对比分析,该近似方法对广义平稳的Wiener过程十分有效,通过近似K-L变换绕开了求解Fredholm积分方程,可运用计算机方便地实现检测信号的似然比计算。
关键词 近似K-L变换 近似特征函数 近似特征值 近似K-L修正展开式
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基于JADE与特征提取的正交/非正交空时分组码盲识别 被引量:7
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作者 张天骐 范聪聪 +1 位作者 喻盛琪 赵健根 《系统工程与电子技术》 EI CSCD 北大核心 2020年第4期933-939,共7页
针对非协作多输入多输出通信系统中正交空时分组码(orthogonal space-time block codes,OSTBC)与非正交空时分组码(non-orthogonal space-time block code,NOSTBC)的盲识别问题,提出结合特征值矩阵联合近似对角化(joint approximate dia... 针对非协作多输入多输出通信系统中正交空时分组码(orthogonal space-time block codes,OSTBC)与非正交空时分组码(non-orthogonal space-time block code,NOSTBC)的盲识别问题,提出结合特征值矩阵联合近似对角化(joint approximate diagonalization of eigenvalue matrix,JADE)与特征提取的盲识别方法。首先将接收信号转换为盲源分离问题中的线性瞬时混合模型,然后利用JADE算法估计出该模型的虚拟信道矩阵,根据该信道矩阵的相关矩阵为数量矩阵的特点,从相关矩阵中提取特征参数,利用此特征参数识别OSTBC与NOSTBC。仿真结果表明,在较低信噪比以及不同的调制模式下,所提方法均可有效识别出OSTBC与NOSTBC。 展开更多
关键词 正交空时分组码 非正交空时分组码 特征值矩阵联合近似对角化 特征提取 盲识别
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Poisson方程特征值的四种有限元解及比较 被引量:16
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作者 刘会坡 严宁宁 《数值计算与计算机应用》 CSCD 2005年第2期81-91,共11页
本文应用双线性元、旋转双线性元、拓广旋转双线性元、Wilson元计算Poisson方程的近似特征值.计算结果验证了[4]中特征值问题的有限元渐进误差展开理论的正确性.最后,我们分析了旋转双线性元的近似解的特殊情况,并预测了Wilson元给出特... 本文应用双线性元、旋转双线性元、拓广旋转双线性元、Wilson元计算Poisson方程的近似特征值.计算结果验证了[4]中特征值问题的有限元渐进误差展开理论的正确性.最后,我们分析了旋转双线性元的近似解的特殊情况,并预测了Wilson元给出特征值的下界. 展开更多
关键词 POISSON方程 有限元解 WILSON元 特征值问题 近似特征值 线性元 误差展开 计算结果 特殊情况 旋转 正确性 元计算 近似 拓广 下界
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基于反幂法和扩展卡尔曼滤波的姿态估计算法 被引量:1
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作者 张雄 黄卫华 陈劲峰 《计算机工程与设计》 北大核心 2020年第1期100-106,共7页
针对基于Davenport的四元数法和扩展卡尔曼(extended Kalman filtering,EKF)的姿态估计算法的精度受特征值精度影响的问题,设计一种基于反幂法与EKF算法的姿态估计算法。根据Davenport矩阵K的近似特征值,利用反幂法迭代计算出Davenport... 针对基于Davenport的四元数法和扩展卡尔曼(extended Kalman filtering,EKF)的姿态估计算法的精度受特征值精度影响的问题,设计一种基于反幂法与EKF算法的姿态估计算法。根据Davenport矩阵K的近似特征值,利用反幂法迭代计算出Davenport矩阵K的特征向量,将其作为EKF的测量值,降低EKF测量值对特征值的敏感度。为验证算法有效性,搭建四旋翼无人机实验平台,实测实验结果表明,该算法能为无人机提供高精度、实时的姿态信息,实现了无人机的稳定飞行。 展开更多
关键词 反幂法 扩展卡尔曼滤波 近似特征值 无人机 姿态估计
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Remark on Relations Between Different Non-integrable Phases 被引量:1
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作者 GUZhi-Yu QIANShang-Wu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期89-91,共3页
There are three non-integrable phases in literatures: Berry phase, Aharonov-Anandan phase, and Yang phase. This article discusses the definitions and relations between these three non-integrable phases.
关键词 Berry phase A-A phase Yang phase
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A Puzzle of Quantum Phase Transition on Gd-IMC by Tuning of Conduction Electron Concentration
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作者 Negin Kamali Sarvestani Ahmad Yazdani S. Ahmad Ketabi 《Journal of Chemistry and Chemical Engineering》 2014年第1期92-96,共5页
Based on the critical unstable of both crystal and magnetic structure of Gd-intermetallic compound near the competition of two strongly independent subsystem ("local 4f7" and "conduction electron concentration")... Based on the critical unstable of both crystal and magnetic structure of Gd-intermetallic compound near the competition of two strongly independent subsystem ("local 4f7" and "conduction electron concentration"), a new QPT (quantum point transition) is predicted by calculation of: (1) The band structure and density of state by density functional theory where a strong narrowing fluidity of fermions around EF with shifted to negative value "-0.8 eV "is observable in the Gd-intermetalliccompound system while in the Y-case, it is not dominated. An antiferromagnetic state on the fluidity of conduction band can be investigated; (2) The internal magnetic field due to short range exchange interaction Jij between the nearest neighbor of local magnetic moment of stable s-state of Gd (L = 0) through the mean field approximation and of Eigenvalue-Eigenfunction ~.(k) are calculated. While a strong negative value of Jy is predicted, the eigenvalue L(k) of the system shows a strong antiferromagnetic phase in the reciprocal lattice direction 〈010〉, 〈001〉 in the correlation length 3.38 ~A. Although the antiferromagnetic state at Rc 〈_ 3.38 °A is a puzzle but it is completely dominated at Rc = 9 °A after passing through the competition between ).λmin(O) and λmin(π) in the ranger of 3.2 °A 〈 Rc 〈 9 °A. Since both of the antiferromagnetic subsystems are sensitive to the predicted KF, the effect of decreasing of conduction electron is proposed to investigate, the change of the antiferromagnetic ordering state to the competition of ferromagnetic state (in direction 〈010〉) and antiferromagnetic state (in direction 〈001 〉 and 〈 100〉) resulted to paramagnetic state in the long range Rc = 9 °A. 展开更多
关键词 Density functional theory ab initio calculations magnetic structure quantum phase transition.
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Approximate Bound State Solutions of DKP Equation for Any J State in the Presence of Woods-Saxon Potential
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作者 R.Oudi S.Hassanabadi +1 位作者 A.A.Rajabi H.Hasanabadi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第1期15-18,共4页
We study Duffin-Kemmer-Petiau(DKP) equation in the presence of the Woods-Saxon potential and obtain eigenvalues and corresponding eigenfunctions for any J state by using of the Nikiforov-Uvarov(NU) method.The Pekeris ... We study Duffin-Kemmer-Petiau(DKP) equation in the presence of the Woods-Saxon potential and obtain eigenvalues and corresponding eigenfunctions for any J state by using of the Nikiforov-Uvarov(NU) method.The Pekeris approximation is used to deal with centrifugal term. 展开更多
关键词 DKP equation Woods-Saxson potential Pekeris approximation NU method
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Nonsensitive Homotopy-Pade Approach:Anharmonic Oscillators
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作者 GAO Yuan LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期214-220,共7页
In order to investigate a complicated physical system, it is convenient to consider a simple, easy to solve model, which is chosen to reflect as much physics as possible of the original system, as an ideal approximati... In order to investigate a complicated physical system, it is convenient to consider a simple, easy to solve model, which is chosen to reflect as much physics as possible of the original system, as an ideal approximation. Motivated by this fundamental idea, we propose a novel asymptotic method, the nonsensitive homotopy-Pade approach. In this method, homotopy relations are constructed to link the original system with an ideal, solvable model. An artificial homotopy parameter is introduced to the homotopy relations as the normal perturbation parameter to generate the perturbation series, and is used to implement the Padd approximation. Meanwhile, some other auxiliary nonperturbative parameters, which are used to control the convergence of the perturbation series, are inserted to the approximants, and are fixed via the principle of minimal sensitivity. The method is used to study the eigenvalue problem of the quantum anharmonic oscillators. Highly accurate numerical results show its validity. Possible further studies on this method are also briefly discussed. 展开更多
关键词 asymptotic methods nonperturbative techniques quantum anharmonic oscillator
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解大规模非对称矩阵特征问题的精化Arnoldi方法的一种变形 被引量:8
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作者 贾仲孝 陈桂芝 《数值计算与计算机应用》 CSCD 北大核心 2003年第2期101-110,共10页
The refined Arnoldi method proposed by Jia is used for computing some eigen-pairs of large matrices. In contrast to the Arnoldi method, the fundamental dif-ference is that the refined method seeks certain refined Ritz... The refined Arnoldi method proposed by Jia is used for computing some eigen-pairs of large matrices. In contrast to the Arnoldi method, the fundamental dif-ference is that the refined method seeks certain refined Ritz vectors, which aredifferent from the Ritz vectors obtained by the Arnoldi method, from a projection space with minimal residuals to approximate the desired eigenvectors. In com-parison with the Ritz vectors, the refined Ritz vectors are guaranteed to converge theoretically and can converge much faster numerically. In this paper we propose to replace the Ritz values, obtained by the Arnoldi method with respect to a Krylovsubspace, by the ones obtained with respect to the subspace spanned by the refined Ritz vectors. We discuss how to compute these new approximations cheaply and reliably. Theoretical error bounds between the original Ritz values and the new Ritz values are established. Finally, we present a variant of the refined Arnoldi al-gorithm for an augmented Krylov subspace and discuss restarting issue. Numerical results confirm efficiency of the new algorithm. 展开更多
关键词 大规模非对称矩阵 特征问题 精化Arnoldi方法 Ritz向量 RITZ值 精化投影方法 近似特征值
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