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基于正规形理论的电力系统振荡稳定分析 被引量:10
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作者 夏成军 周良松 +1 位作者 彭波 胡会骏 《继电器》 CSCD 北大核心 2001年第8期13-16,共4页
介绍了正规形理论的基本内容及其在电力系统中的应用情况 ,将正规形理论应用于电力系统振荡稳定分析中 ,可以将线性系统中的参与因子的概念推广到非线性系统中 ,为理解系统各振荡模式之间的非线性相互作用提供度量。
关键词 正规形理论 非线性分析 振荡模式 特征值分析 电力系统 稳定分析
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A full multigrid method for nonlinear eigenvalue problems 被引量:7
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作者 JIA ShangHui XIE HeHu +1 位作者 XIE ManTing XU Fei 《Science China Mathematics》 SCIE CSCD 2016年第10期2037-2048,共12页
We introduce a type of full multigrid method for the nonlinear eigenvalue problem. The main idea is to transform the solution of the nonlinear eigenvalue problem into a series of solutions of the corresponding linear ... We introduce a type of full multigrid method for the nonlinear eigenvalue problem. The main idea is to transform the solution of the nonlinear eigenvalue problem into a series of solutions of the corresponding linear boundary value problems on the sequence of finite element spaces and nonlinear eigenvalue problems on the coarsest finite element space. The linearized boundary value problems are solved by some multigrid iterations.Besides the multigrid iteration, all other efficient iteration methods for solving boundary value problems can serve as the linear problem solver. We prove that the computational work of this new scheme is truly optimal,the same as solving the linear corresponding boundary value problem. In this case, this type of iteration scheme certainly improves the overfull efficiency of solving nonlinear eigenvalue problems. Some numerical experiments are presented to validate the efficiency of the new method. 展开更多
关键词 nonlinear eigenvalue problem full multigrid method multilevel correction finite element method
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基于ANSYS的钢结构平面外稳定分析 被引量:6
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作者 林立孚 《工业建筑》 CSCD 北大核心 2011年第S1期388-390,364,共4页
采用ANSYS中非线性屈曲分析、线性屈曲分析(特征值屈曲分析)两种方法来确定结构的临界荷载和结构发生屈曲响应时的特征形状。对ANSYS得到的临界荷载与理论公式的临界荷载进行比较。用ANSYS非线性屈曲分析程序计算压弯构件的临界荷载。... 采用ANSYS中非线性屈曲分析、线性屈曲分析(特征值屈曲分析)两种方法来确定结构的临界荷载和结构发生屈曲响应时的特征形状。对ANSYS得到的临界荷载与理论公式的临界荷载进行比较。用ANSYS非线性屈曲分析程序计算压弯构件的临界荷载。然后利用ANSYS有限元程序和GB 50017-2003《钢结构设计规范》对单跨对称门式刚架进行平面外稳定分析。 展开更多
关键词 平面外稳定 非线性屈曲分析 特征值屈曲分析 门式刚架 ANSYS模型
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Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
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作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
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一个带周期边界条件的非线性特征值问题 被引量:3
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作者 李祖平 李灵晓 王燕 《河南科技大学学报(自然科学版)》 CAS 2006年第1期72-74,共3页
将一个带周期边界条件的非线性特征值问题线性化,构造有界凸闭子集上的一个紧映射,利用不动点定理得出该映射的不动点,而此不动点恰好为非线性问题的解,借以证明特征值的存在性,并利用线性问题的结果得到非线性问题的相应结果。
关键词 周期 边界条件 非线性 特征值问题 线性化 特征函数 不动点定理
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一个四阶非线性微分算子的特征值问题 被引量:3
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作者 赵晓花 李灵晓 《河南科技大学学报(自然科学版)》 CAS 2007年第4期78-80,共3页
研究了一个四阶微分算子的非线性特征值问题,首先利用对称全连续算子谱理论得到线性情况下的特征值结果,然后将非线性问题线性化,利用Schauder不动点定理得到一个不动点,而此不动点恰为非线性问题的解,借以证明特征值的存在及相应的估计。
关键词 全连续算子 特征函数 非线性特征值 紧映射 SCHAUDER不动点定理
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拟Newton法在高阶矩阵中的应用——求解最大特征值及特征向量 被引量:3
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作者 何超 刘西林 李佳珍 《计算机工程与应用》 CSCD 2012年第16期33-36,84,共5页
将求解高阶矩阵的最大特征值及其对应的特征向量问题转化为高阶非线性方程组的求解问题。在此基础上,提出了求解矩阵最大特征值及其对应特征向量的拟Newton法,给出求解矩阵最大特征值及其单位化向量重新整理后的Broyden方法公式、BFS方... 将求解高阶矩阵的最大特征值及其对应的特征向量问题转化为高阶非线性方程组的求解问题。在此基础上,提出了求解矩阵最大特征值及其对应特征向量的拟Newton法,给出求解矩阵最大特征值及其单位化向量重新整理后的Broyden方法公式、BFS方法公式、DFP方法公式及其对应的Broyden算法,BFS算法,DFP算法。以层次分析法中高阶判断矩阵为例验证了该方法的可行性,说明了该方法相对收敛速度快的优势。 展开更多
关键词 矩阵 非线性方程组 最大特征值 特征向量 拟NEWTON法
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有限元线法求解非线性模型问题——Ⅲ.薄膜的固有振动 被引量:2
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作者 张亿果 袁驷 《工程力学》 EI CSCD 1993年第3期1-8,共8页
本文是有限元线法(FEMOL)求解非线性模型问题的系列工作之三,对薄膜的固有振动这一特征值模型问题作了分析求解。文中,首先用FEMOL对特征值问题的泛函进行半离散,得到相应的常微分方程(ODE)特性值问题;然后,利用若干ODE变换技巧将问题... 本文是有限元线法(FEMOL)求解非线性模型问题的系列工作之三,对薄膜的固有振动这一特征值模型问题作了分析求解。文中,首先用FEMOL对特征值问题的泛函进行半离散,得到相应的常微分方程(ODE)特性值问题;然后,利用若干ODE变换技巧将问题转换成标准的非线性ODE问题;最后,采用一个新近研究出的有效算法,对各阶特征对进行了方便有效、精确可靠的求解。文中出示的算例展示了该法的功效。 展开更多
关键词 有限元线法 非线性问题 特征值 固有振动
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四阶非线性特征值问题的正解
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作者 马巧珍 《甘肃科学学报》 2000年第4期81-85,共5页
证明了四阶非线性特征值问题y(4) - λa(x) f(y(x) ) =0  0 <x<1y(0 ) =y(1 ) =y″(0 ) =y″(1 ) =0正解的存在性。主要工具是 Krasnoselskii不动点定理。
关键词 四阶非线性特征值 正解 存在性 KRASNOSELSKII不动点定理 边值问题
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基于拟力法的负刚度非线性分析 被引量:2
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作者 李钢 李凯 +1 位作者 余丁浩 杨树标 《防灾减灾工程学报》 CSCD 北大核心 2018年第2期216-223,共8页
拟力法是一种高效的结构非线性分析方法,当结构进入非线性状态时,拟力法仅需对一个代表局部塑性且规模较小的矩阵进行迭代运算,从而避免了传统方法对规模较大的整体刚度矩阵的分解运算。拟力法在处理负刚度问题时,结构的非线性特征由局... 拟力法是一种高效的结构非线性分析方法,当结构进入非线性状态时,拟力法仅需对一个代表局部塑性且规模较小的矩阵进行迭代运算,从而避免了传统方法对规模较大的整体刚度矩阵的分解运算。拟力法在处理负刚度问题时,结构的非线性特征由局部塑性矩阵集中体现。研究了负刚度条件下拟力法中局部塑性矩阵的正负定特性及条件数与最小特征值等数值特征,得到了第二刚度系数对矩阵数值特征的影响规律,并与传统方法中整体刚度矩阵的相应特征进行了对比分析。结果表明,结构进入负刚度状态时,拟力法中局部塑性矩阵将表现为非正定性,且相比于整体刚度矩阵,数值模拟表明其具有条件数少、数值精度高的特征。最后通过数值算例验证了拟力法在计算负刚度问题的优势与计算能力。 展开更多
关键词 拟力法 负刚度 非线性分析 条件数 最小特征值
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三维声学特征频率灵敏度分析的边界元法 被引量:1
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作者 余志强 刘强 郑昌军 《计算力学学报》 CAS CSCD 北大核心 2023年第4期634-640,共7页
声系统特征频率的灵敏度分析为其优化设计提供了基础,具有重要意义。边界元法在声学问题的求解中具有独特优势,但因其系统方程系数矩阵的频率相关性导致的非线性特征值问题给声学特征频率的灵敏度分析带来了很大困难。为此,本文首先对... 声系统特征频率的灵敏度分析为其优化设计提供了基础,具有重要意义。边界元法在声学问题的求解中具有独特优势,但因其系统方程系数矩阵的频率相关性导致的非线性特征值问题给声学特征频率的灵敏度分析带来了很大困难。为此,本文首先对非线性特征值问题进行了线性化处理,利用围道积分投影方法将非线性特征方程转换为小规模广义特征方程,然后对其关于设计变量直接求导,并引入左特征向量和转换矩阵构造了一种适用于内外声场的三维声学单/重特征频率灵敏度分析的边界元法。数值算例验证了该方法的适用性,以及对单/重特征频率灵敏度的计算精度。 展开更多
关键词 声模态 特征频率灵敏度 边界元法 非线性特征值 围道积分法
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Periodic Eigenvalues of One-Dimensional p-Laplacian with Indefinite Weights
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作者 晏平 章梅荣 《Tsinghua Science and Technology》 SCIE EI CAS 2003年第5期533-536,共4页
Rotation numbers are used in this paper to study the periodic and anti-periodic eigenvalues of the one-dimensional p-Laplacian with a periodic weight which changes sign. The analysis proves that for any nonnegative i... Rotation numbers are used in this paper to study the periodic and anti-periodic eigenvalues of the one-dimensional p-Laplacian with a periodic weight which changes sign. The analysis proves that for any nonnegative integer n, ρ -1(n/2) is the union of two closed intervals, one of which lies in [FK(W+3mm?3mm][TPP533A,+3mm?2mm] + and the other in [FK(W+3mm?3mm][TPP533A,+3mm?2mm] -, and the endpoints of these intervals yield the corresponding periodic and anti-periodic eigenvalues. 展开更多
关键词 nonlinear eigenvalue P-LAPLACIAN p-cosine p-sine rotation number
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Best Estimates of Weighted Eigenvalues of One-dimensional p-Laplacian
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作者 晏平 章梅荣 《Northeastern Mathematical Journal》 CSCD 2003年第1期39-50,共12页
In this paper, we determine the infimum and the supremum of the Dirich-let eigenvalues λn(p) (n = 1,2,…)of the problem t∈ ?[0,T], where 1 < p < ∞, and the weights p are nonnegative and are subject to conditi... In this paper, we determine the infimum and the supremum of the Dirich-let eigenvalues λn(p) (n = 1,2,…)of the problem t∈ ?[0,T], where 1 < p < ∞, and the weights p are nonnegative and are subject to conditions p(t)dt = M and max(e[0,T] p(t) = H. It is also explained for whatweights p the infimum and the supremum will be attained. 展开更多
关键词 nonlinear eigenvalue P-LAPLACIAN p-cosine p-sine comparison theorem
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POSITIVE SOLUTIONS FOR PARAMETRIC EQUIDIFFUSIVE p-LAPLACIAN EQUATIONS
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作者 Leszek GASINSKI Nikolaos S.PAPAGEORGIOU 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期610-618,共9页
We consider a parametric Dirichlet problem driven by the p-Laplacian with a Caratheodory reaction of equidiffusive type. Our hypotheses incorporate as a special case the equidiffusive p-logistic equation. We show that... We consider a parametric Dirichlet problem driven by the p-Laplacian with a Caratheodory reaction of equidiffusive type. Our hypotheses incorporate as a special case the equidiffusive p-logistic equation. We show that if λ1 〉 0 is the principal eigenvalue of the Dirichlet negative p-Laplacian and )λ 〉 λ1 (/k being the parameter), the problem has a unique positive solution, while for )λ ∈ (0, λ1], the problem has no positive solution. 展开更多
关键词 P-LAPLACIAN p-logistic equation first eigenvalue equidiffusive reaction maxi-mum principle nonlinear regularity
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Evolution of the First Eigenvalue of a (<i>p</i>,<i>q</i>)-Laplacian Under a Harmonic Ricci Flow
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作者 Paul Bracken 《Advances in Pure Mathematics》 2021年第4期205-217,共13页
The properties of the first eigenvalue of a class of (<em>p</em>,<em>q</em>) Laplacian are investigated. A variational formulation for the first eigenvalue of the Laplacian on a closed Riemanni... The properties of the first eigenvalue of a class of (<em>p</em>,<em>q</em>) Laplacian are investigated. A variational formulation for the first eigenvalue of the Laplacian on a closed Riemannian manifold is obtained. This eigenvalue corresponds to a nonlinear, coupled system of <em>p</em>-Laplacian partial differential equations. The main idea is to investigate the evolution of the first eigenvalue of the system under the Ricci harmonic flow. It is also possible to construct monotonic quantities based on them and study their evolution which is done. 展开更多
关键词 Ricci Flow Curvature eigenvalue EVOLUTION LAPLACIAN nonlinear
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Takagi-Sugeno Fuzzy Regulator Design for Nonlinear and Unstable Systems Using Negative Absolute Eigenvalue Approach
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作者 Ravi V.Gandhi Dipak M.Adhyaru 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第2期482-493,共12页
This paper introduces a Takagi-Sugeno(T-S)fuzzy regulator design using the negative absolute eigenvalue(NAE)approach for a class of nonlinear and unstable systems.The open-loop system is initially embodied by the trad... This paper introduces a Takagi-Sugeno(T-S)fuzzy regulator design using the negative absolute eigenvalue(NAE)approach for a class of nonlinear and unstable systems.The open-loop system is initially embodied by the traditional T-S fuzzy model and then,all closed-loop subsystems are combined using the proposed Max-Min operator in place of traditional weighted average operator from the controller side to lessen the coupling virtually and simplify the proposed regulator design.For each virtually decoupled closed-loop subsystem,the composite regulators(i.e.,primary and secondary regulators)are designed by the NAE approach based on the enhanced eigenvalue analysis.The Lyapunov function is utilized to guarantee the asymptotic stability of the overall T-S fuzzy control system.The most popular and widely used nonlinear and unstable systems like the electromagnetic levitation system(EMLS)and the inverted cart pendulum(ICP)are simulated for the wide range of the initial conditions and the enormous variation in the disturbance.The transient and steady-state performance of the considered systems using the proposed design are analyzed in terms of the decay rate,settling time and integral errors as IAE,ISE,ITAE,and ITSE to validate the effectiveness of the proposed approach compared to the most popular and traditional parallel distributed compensation(PDC)approach. 展开更多
关键词 eigenvalue approach nonlinear and unstable systems stability analysis Takagi-Sugeno(T-S)fuzzy regulator
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非线性系统Hopf分叉临界点的稳定性 被引量:1
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作者 陈宇东 裴春艳 曹宗杰 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2009年第4期993-996,共4页
由于参数的小扰动,非线性系统Hopf分叉临界点的亏损特征值可分离为密集特征值。利用Puiseux展开式讨论了Hopf分叉临界点的特征值分叉现象,同时讨论了在临界点的响应显式解。这些结果具有明确的物理意义,并可用来说明非线性系统在Hopf分... 由于参数的小扰动,非线性系统Hopf分叉临界点的亏损特征值可分离为密集特征值。利用Puiseux展开式讨论了Hopf分叉临界点的特征值分叉现象,同时讨论了在临界点的响应显式解。这些结果具有明确的物理意义,并可用来说明非线性系统在Hopf分叉临界点附近的不稳定性的机理。最后给出了本文方法在机翼模型中的应用。 展开更多
关键词 固体力学 非线性系统 Hopf分叉的临界点 特征值分叉 稳定性分析
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Band Structure Calculations of Dispersive Photonic Crystals in 3D using Holomorphic Operator Functions
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作者 Wenqiang Xiao Bo Gong +1 位作者 Junshan Lin Jiguang Sun 《Communications in Computational Physics》 SCIE 2023年第2期628-646,共19页
We propose a finite element method to compute the band structures of dispersive photonic crystals in 3D.The nonlinear Maxwell’s eigenvalue problem is formulated as the eigenvalue problem of a holomorphic operator fun... We propose a finite element method to compute the band structures of dispersive photonic crystals in 3D.The nonlinear Maxwell’s eigenvalue problem is formulated as the eigenvalue problem of a holomorphic operator function.The N´ed´elec edge elements are employed to discretize the operators,where the divergence free condition for the electric field is realized by a mixed form using a Lagrange multiplier.The convergence of the eigenvalues is proved using the abstract approximation theory for holomorphic operator functions with the regular approximation of the edge elements.The spectral indicator method is then applied to compute the discrete eigenvalues.Numerical examples are presented demonstrating the effectiveness of the proposed method. 展开更多
关键词 Band structure dispersive photonic crystal Maxwell’s equations nonlinear eigenvalue problem edge element holomorphic operator function
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Bifurcation control and eigenstructure assignment in continuous solution polymerization of vinyl acetate 被引量:1
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作者 张楠 邱彤 陈丙珍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第9期1523-1529,共7页
The major difficulty in achieving good performance of industrial polymerization reactors lies in the lack of understanding of their nonlinear dynamics and the lack of well-developed techniques for the control of nonli... The major difficulty in achieving good performance of industrial polymerization reactors lies in the lack of understanding of their nonlinear dynamics and the lack of well-developed techniques for the control of nonlinear processes, which are usually accompanied with bifurcation phenomenon. This work aims at investigating the nonlinear behavior of the parameterized nonlinear system of vinyl acetate polymerization and further modifying the bifurcation characteristics of this process via a washout filter-aid controller, with all the original steady state equilibria preserved. Advantages and possible extensions of the proposed methodology are discussed to provide scientific guide for further controller design and operation improvement. 展开更多
关键词 Vinyl acetate polymerization nonlinear dynamics Bifurcation control eigenvalue assignment Washout filters
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Maximization of the sum of the trace ratio on the Stiefel manifold, I: Theory 被引量:1
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作者 ZHANG LeiHong LI RenCang 《Science China Mathematics》 SCIE 2014年第12期2495-2508,共14页
We are concerned with the maximization of tr(V T AV)/tr(V T BV)+tr(V T CV) over the Stiefel manifold {V ∈ R m×l | V T V = Il} (l 〈 m), where B is a given symmetric and positive definite matrix, A and... We are concerned with the maximization of tr(V T AV)/tr(V T BV)+tr(V T CV) over the Stiefel manifold {V ∈ R m×l | V T V = Il} (l 〈 m), where B is a given symmetric and positive definite matrix, A and C are symmetric matrices, and tr(. ) is the trace of a square matrix. This is a subspace version of the maximization problem studied in Zhang (2013), which arises from real-world applications in, for example, the downlink of a multi-user MIMO system and the sparse Fisher discriminant analysis in pattern recognition. We establish necessary conditions for both the local and global maximizers and connect the problem with a nonlinear extreme eigenvalue problem. The necessary condition for the global maximizers offers deep insights into the problem, on the one hand, and, on the other hand, naturally leads to a self-consistent-field (SCF) iteration to be presented and analyzed in detail in Part II of this paper. 展开更多
关键词 trace ratio Rayleigh quotient Stiefel manifold nonlinear eigenvalue problem optimality condition EIGENSPACE
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