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Kraus operator solutions to a fermionic master equation describing a thermal bath and their matrix representation 被引量:2
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作者 孟祥国 王继锁 +1 位作者 范洪义 夏承魏 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期42-46,共5页
We solve the fermionic master equation for a thermal bath to obtain its explicit Kraus operator solutions via the fermionic state approach. The normalization condition of the Kraus operators is proved. The matrix repr... We solve the fermionic master equation for a thermal bath to obtain its explicit Kraus operator solutions via the fermionic state approach. The normalization condition of the Kraus operators is proved. The matrix representation for these solutions is obtained, which is incongruous with the result in the book completed by Nielsen and Chuang [Quan- tum Computation and Quantum Information, Cambridge University Press, 2000]. As especial cases, we also present the Kraus operator solutions to master equations for describing the amplitude-decay model and the diffusion process at finite temperature. 展开更多
关键词 Kraus operator solution matrix representation thermal bath fermionic entangled state represen-tation
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THE SCHUR TEST OF COMPACT OPERATORS
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作者 Qijian KANG Maofa WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期2041-2050,共10页
Infinite matrix theory is an important branch of function analysis.Every linear operator on a complex separable infinite dimensional Hilbert space corresponds to an infinite matrix with respect a orthonormal base of t... Infinite matrix theory is an important branch of function analysis.Every linear operator on a complex separable infinite dimensional Hilbert space corresponds to an infinite matrix with respect a orthonormal base of the space,but not every infinite matrix corresponds to an operator.The classical Schur test provides an elegant and useful criterion for the boundedness of linear operators,which is considered a respectable mathematical accomplishment.In this paper,we prove the compact version of the Schur test.Moreover,we provide the Schur test for the Schatten class S_(2).It is worth noting that our main results can be applicable to the general matrix without limitation on non-negative numbers.We finally provide the Schur test for compact operators from l_(p) into l_(q). 展开更多
关键词 Schur test compact operator infinite matrix
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A CHARACTERIZATION OF SCHECHTER'S ESSENTIAL SPECTRUM BY MEAN OF MEASURE OF NON-STRICT-SINGULARITY AND APPLICATION TO MATRIX OPERATOR 被引量:1
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作者 Nedra Moalla 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2329-2340,共12页
In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linea... In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linear operator. 展开更多
关键词 measure of non-strict-singularity Fredholm operator Schechter essentialspectrum matrix operator
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CHARACTERIZATIONS OF SOME MATRIX CLASSES OF QUASI-HOMOGENEOUS OPERATORS 被引量:1
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作者 陈爱红 李容录 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2285-2294,共10页
In this paper, we give a general characterization of a class of matrices of quasi-homogeneous operators between topological vector spaces.
关键词 matrix transformation quasi-homogeneous operator gliding hump property
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Structure of continuous matrix product operator for transverse field Ising model:An analytic and numerical study
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作者 Yueshui Zhang Lei Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期121-142,共22页
We study the structure of the continuous matrix product operator(cMPO)^([1]) for the transverse field Ising model(TFIM).We prove TFIM’s cMPO is solvable and has the form T=e^(-1/2H_(F)).H_(F) is a non-local free ferm... We study the structure of the continuous matrix product operator(cMPO)^([1]) for the transverse field Ising model(TFIM).We prove TFIM’s cMPO is solvable and has the form T=e^(-1/2H_(F)).H_(F) is a non-local free fermionic Hamiltonian on a ring with circumferenceβ,whose ground state is gapped and non-degenerate even at the critical point.The full spectrum of H_(F) is determined analytically.At the critical point,our results verify the state–operator-correspondence^([2]) in the conformal field theory(CFT).We also design a numerical algorithm based on Bloch state ansatz to calculate the lowlying excited states of general(Hermitian)cMPO.Our numerical calculations coincide with the analytic results of TFIM.In the end,we give a short discussion about the entanglement entropy of cMPO’s ground state. 展开更多
关键词 continuous matrix product operator transverse field Ising model state-operator-correspondence
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Completeness of the system of eigenvectors of off-diagonal operator matrices and its applications in elasticity theory 被引量:7
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作者 黄俊杰 阿拉坦仓 王华 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期9-17,共9页
This paper deals with off-diagonal operator matrices and their applications in elasticity theory. Two kinds of completeness of the system of eigenvectors are proven, in terms of those of the compositions of two block ... This paper deals with off-diagonal operator matrices and their applications in elasticity theory. Two kinds of completeness of the system of eigenvectors are proven, in terms of those of the compositions of two block operators in the off-diagonal operator matrices. Using these results, the double eigenfunction expansion method for solving upper triangular matrix differential systems is proposed. Moreover, we apply the method to the two-dimensional elasticity problem and the problem of bending of rectangular thin plates on elastic foundation. 展开更多
关键词 off-diagonal operator matrix COMPLETENESS double eigenfunction expansion method elasticity theory
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Completeness of eigenfunction systems for the product of two symmetric operator matrices and its application in elasticity 被引量:3
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作者 齐高娃 侯国林 阿拉坦仓 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期264-272,共9页
The completeness theorem of the eigenfunction systems for the product of two 2 × 2 symmetric operator matrices is proved. The result is applied to 4 × 4 infinite-dimensional Hamiltonian operators. A modified... The completeness theorem of the eigenfunction systems for the product of two 2 × 2 symmetric operator matrices is proved. The result is applied to 4 × 4 infinite-dimensional Hamiltonian operators. A modified method of separation of variables is proposed for a separable Hamiltonian system. As an application of the theorem, the general solutions for the plate bending equation and the free vibration of rectangular thin plates are obtained. Finally, a numerical test is analysed to show the correctness of the results. 展开更多
关键词 operator matrix Hamiltonian operator symplectic orthogonal eigenfunction system completeness
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CHARACTERIZATIONS OF COMPACT OPERATORS ON SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m 被引量:2
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作者 Ivana Djolovi Eberhard Malkowsky 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1465-1474,共10页
In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ (... In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ ( m ) ) and e r ∞ (△ ( m ) ) and characterized some classes of matrix transformations on them. In our paper, we add a new supplementary aspect to their research by characterizing classes of compact operators on those spaces. For that purpose, the spaces are treated as the matrix domains of a triangle in the classical sequence spaces c 0 , c and ∞ . The main tool for our characterizations is the Hausdorff measure of noncompactness. 展开更多
关键词 difference sequence spaces of order m matrix transformations compact operators Hausdorff measure of noncompactness
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On the completeness of eigen and root vector systems for fourth-order operator matrices and their applications 被引量:1
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作者 王华 阿拉坦仓 黄俊杰 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期8-14,共7页
In this paper, we consider the eigenvalue problem of a class of fourth-order operator matrices appearing in mechan- ics, including the geometric multiplicity, algebraic index, and algebraic multiplicity of the eigenva... In this paper, we consider the eigenvalue problem of a class of fourth-order operator matrices appearing in mechan- ics, including the geometric multiplicity, algebraic index, and algebraic multiplicity of the eigenvalue, the symplectic orthogonality, and completeness of eigen and root vector systems. The obtained results are applied to the plate bending problem. 展开更多
关键词 operator matrix eigenvalue problem EIGENVECTOR root vector COMPLETENESS
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ON SPECTRAL PROPERTIES OF A NEW OPERATOR OVER SEQUENCE SPACES c AND c_0 被引量:1
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作者 Ezgi ERDOGAN Vatan KARAKAYA 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1481-1494,共14页
In this work, we classify and calculate spectra such as point spectrum, continuous spectrum and residual spectrum over sequences spaces?∞, c and c0 according to a new matrix operator W which is obtained by matrix pr... In this work, we classify and calculate spectra such as point spectrum, continuous spectrum and residual spectrum over sequences spaces?∞, c and c0 according to a new matrix operator W which is obtained by matrix product. 展开更多
关键词 spectrum of an operator matrix transformation sequence space
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Furi-Martelli-Vignoli spectrum and Feng spectrum of nonlinear block operator matrices 被引量:1
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作者 Xiao-Mei Dong De-Yu Wu Alatancang Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期130-138,共9页
We investigate the Furi-Martelli-Vignoli spectrum and the Feng spectrum of continuous nonlinear block operator matrices,and mainly describe the relationship between the Furi-Martelli-Vignoli spectrum(compared to the F... We investigate the Furi-Martelli-Vignoli spectrum and the Feng spectrum of continuous nonlinear block operator matrices,and mainly describe the relationship between the Furi-Martelli-Vignoli spectrum(compared to the Feng spectrum)of the whole operator matrix and that of its entries.In addition,the connection between the Furi-Martelli-Vignoli spectrum of the whole operator matrix and that of its Schur complement is presented by means of Schur decomposition. 展开更多
关键词 nonlinear operator SPECTRUM block operator matrix
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Symplectic eigenvector expansion theorem of a class of operator matrices arising from elasticity theory
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作者 王华 阿拉坦仓 黄俊杰 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期92-97,共6页
This paper deals with the completeness of the eigenvector system of a class of operator matrices arising from elasticity theory, i.e., symplectic eigenvector expansion theorem. Under certain conditions, the symplectic... This paper deals with the completeness of the eigenvector system of a class of operator matrices arising from elasticity theory, i.e., symplectic eigenvector expansion theorem. Under certain conditions, the symplectic orthogonality of eigenvectors of the operator matrix is demonstrated. Based on this, a necessary and sufficient condition for the completeness of the eigenvector system of the operator matrix is given. Furthermore, the obtained results are tested for the free vibration of rectangular thin plates. 展开更多
关键词 operator matrix EIGENVECTOR COMPLETENESS eigenvector expansion theorem
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双级矩阵变换器Delta-Sigma变频调制策略
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作者 周湛清 谢琦坤 耿强 《天津工业大学学报》 北大核心 2025年第1期69-74,共6页
针对定开关频率调制下输出侧含有高频谐波边带的问题,提出了双级矩阵变换器变频调制策略,以提升双级矩阵变换器的电磁兼容性能以及运行性能。将Delta-Sigma矢量调制技术应用于双级矩阵变换器的逆变级中,基于仿真与实验结果分析了该调制... 针对定开关频率调制下输出侧含有高频谐波边带的问题,提出了双级矩阵变换器变频调制策略,以提升双级矩阵变换器的电磁兼容性能以及运行性能。将Delta-Sigma矢量调制技术应用于双级矩阵变换器的逆变级中,基于仿真与实验结果分析了该调制策略下的双级矩阵变换器运行性能。仿真与实验结果表明:本文所提调制策略有效实现了双级矩阵变换器输出电流的频谱整形,不再含有高频谐波尖峰,有效降低了输出侧相电流高频谐波边带的幅值;本文调制策略下双级矩阵变换器输出相电流THD最高为4.26%,最低为1.62%,相较于空间矢量调制策略输出相电流THD平均降低了0.256%,这表明本文策略具有良好的运行性能;动态实验结果表明该策略具有良好的动态特性。 展开更多
关键词 双级矩阵变换器 Delta-Sigma调制 变频调制 频谱整形 运行性能
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基于SVT的广义斜投影三维极化滤波方法
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作者 王栗沅 何华锋 +2 位作者 何耀民 韩晓斐 李震 《北京航空航天大学学报》 北大核心 2025年第2期633-643,共11页
针对不同噪声背景下广义斜投影滤波存在滤波“死角”,且易受噪声协方差矩阵估计误差影响的问题,提出了一种基于奇异值阈值(SVT)的广义斜投影极化-空域联合滤波方法。以均匀圆阵极化敏感阵列为基础建立阵列接收信号模型;利用最小化干扰... 针对不同噪声背景下广义斜投影滤波存在滤波“死角”,且易受噪声协方差矩阵估计误差影响的问题,提出了一种基于奇异值阈值(SVT)的广义斜投影极化-空域联合滤波方法。以均匀圆阵极化敏感阵列为基础建立阵列接收信号模型;利用最小化干扰约束广义斜投影算子设计广义斜投影三维极化滤波器;在干扰参数未知的情况下,提出了一种基于SVT的滤波权矢量计算方法;通过对滤波器性能进行理论分析并与三种同类方法仿真对比,结果表眀:基于SVT的广义斜投影三维极化滤波方法能够在无需估计噪声协方差矩阵的条件下实现干扰抑制并恢复出目标信号。 展开更多
关键词 阵列信号处理 斜投影 低秩矩阵恢复 线性约束最小方差 奇异值阈值算子
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Graph Laplacian Matrix Learning from Smooth Time-Vertex Signal 被引量:2
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作者 Ran Li Junyi Wang +2 位作者 Wenjun Xu Jiming Lin Hongbing Qiu 《China Communications》 SCIE CSCD 2021年第3期187-204,共18页
In this paper,we focus on inferring graph Laplacian matrix from the spatiotemporal signal which is defined as“time-vertex signal”.To realize this,we first represent the signals on a joint graph which is the Cartesia... In this paper,we focus on inferring graph Laplacian matrix from the spatiotemporal signal which is defined as“time-vertex signal”.To realize this,we first represent the signals on a joint graph which is the Cartesian product graph of the time-and vertex-graphs.By assuming the signals follow a Gaussian prior distribution on the joint graph,a meaningful representation that promotes the smoothness property of the joint graph signal is derived.Furthermore,by decoupling the joint graph,the graph learning framework is formulated as a joint optimization problem which includes signal denoising,timeand vertex-graphs learning together.Specifically,two algorithms are proposed to solve the optimization problem,where the discrete second-order difference operator with reversed sign(DSODO)in the time domain is used as the time-graph Laplacian operator to recover the signal and infer a vertex-graph in the first algorithm,and the time-graph,as well as the vertex-graph,is estimated by the other algorithm.Experiments on both synthetic and real-world datasets demonstrate that the proposed algorithms can effectively infer meaningful time-and vertex-graphs from noisy and incomplete data. 展开更多
关键词 Cartesian product graph discrete secondorder difference operator Gaussian prior distribution graph Laplacian matrix learning spatiotemporal smoothness time-vertex signal
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MatrixVB在测量数据处理中的应用 被引量:1
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作者 林永秋 《福建建设科技》 2010年第3期68-71,共4页
本文介绍了MatrixVB的主要功能以及引用方式,并且重点介绍了在测量数据处理中比较重要的两个方面,即矩阵运算以及图形处理。通过本文的实例可以发现,在VB中加载了MatrixVB插件之后,使得程序代码编写的负担大大减轻。MATLAB和VB具有较好... 本文介绍了MatrixVB的主要功能以及引用方式,并且重点介绍了在测量数据处理中比较重要的两个方面,即矩阵运算以及图形处理。通过本文的实例可以发现,在VB中加载了MatrixVB插件之后,使得程序代码编写的负担大大减轻。MATLAB和VB具有较好的互补性,采用MatrixVB和VB混合编程,既保留了MATLAB强大的矩阵运算图形处理等功能,又集成了VB高级语言界面友好易于编译等优点。说明了采用MatrixVB和VB混合编程在测量数据处理中具有较好的实用价值。 展开更多
关键词 matrixVB MATLAB VB 测量数据处理 矩阵运算 图形处理
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加强水库安全管理的对策建议 被引量:3
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作者 刘六宴 张士辰 《中国水利》 2024年第14期1-4,共4页
为对标高质量发展新要求,顺应新质生产力发展方向,确保水库大坝安全稳定运行,对我国水库大坝的主要特点进行了梳理概括,通过分析我国水库安全管理面临的新形势新任务,提出要综合运用法律、技术、经济等手段,坚持治水思路、问题导向、底... 为对标高质量发展新要求,顺应新质生产力发展方向,确保水库大坝安全稳定运行,对我国水库大坝的主要特点进行了梳理概括,通过分析我国水库安全管理面临的新形势新任务,提出要综合运用法律、技术、经济等手段,坚持治水思路、问题导向、底线思维、预防为主、系统观念、创新发展。结合当前水库安全管理存在的主要问题,提出相关对策建议,包括坚持“安全第一”方针、完善法规制度标准、构建运行管理矩阵、压实管理责任、加强库容管理、加强安全监测、加强应急管理、加强队伍能力建设等,为下一步加强水库安全管理提供参考。 展开更多
关键词 水库大坝 安全管理 库容管理 现代化水库运行管理矩阵
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现代化水库运行管理矩阵体系分析与构建关键问题研究 被引量:2
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作者 方卫华 袁威 杨浩东 《中国水利》 2024年第4期53-60,共8页
为支撑行业重点任务建设,提高现代化水库运行管理矩阵的建设水平,通过文献查阅、实地考察和交流咨询等方法,绘制了以工程安全、设施设备、影响区、运行调度和管理监督5个关键环节为一体的现代化水库运行管理矩阵构建体系“一张图”。给... 为支撑行业重点任务建设,提高现代化水库运行管理矩阵的建设水平,通过文献查阅、实地考察和交流咨询等方法,绘制了以工程安全、设施设备、影响区、运行调度和管理监督5个关键环节为一体的现代化水库运行管理矩阵构建体系“一张图”。给出了现代化水库运行管理矩阵的整体架构、层次演进和各要素之间的相互关系,系统梳理了现代化水库运行管理矩阵提出的背景、内涵和要求,对“四全”、“四制(治)”、“四预”、“四管”和雨水情监测预报、工程安全风险感控、生产安全风险感控“三道防线”的对象进行了系统整合和扩展,分析了各概念之间的相互关系和关键技术问题。研究结果表明,构建现代化水库运行管理矩阵是科技和管理水平发展的必然要求。 展开更多
关键词 现代化水库运行管理矩阵 一张图 风险管理 智慧管理 三道防线 四预
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构建现代化水库运行管理矩阵与发展水利新质生产力 被引量:3
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作者 刘六宴 《中国水利》 2024年第9期5-8,共4页
加强水库安全管理具有极端重要性。分析了构建现代化水库运行管理矩阵、发展水利新质生产力对保障水库高水平安全的重大意义,从高科技、高效能、高质量三个维度阐释构建现代化水库运行管理矩阵与发展水利新质生产力的内在联系,提出强化... 加强水库安全管理具有极端重要性。分析了构建现代化水库运行管理矩阵、发展水利新质生产力对保障水库高水平安全的重大意义,从高科技、高效能、高质量三个维度阐释构建现代化水库运行管理矩阵与发展水利新质生产力的内在联系,提出强化“四全”管理、“四预”措施与信息技术深度融合等加快构建现代化水库运行管理矩阵、助力发展水利新质生产力的主要路径。 展开更多
关键词 水库安全管理 运行管理矩阵 水利新质生产力 高质量发展 高水平安全
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套代数上的一类非线性中心化子
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作者 纪玉德 吴冰 杨翠 《河北科技大学学报》 CAS 北大核心 2024年第2期176-180,共5页
为了推广算子代数中的基本理论,对一类非线性映射成为套代数上的可加中心化子的条件进行了研究。首先,基于Hilbert空间上的非平凡套定义与该套有关的套代数,并定义套代数上的一个非线性映射;其次,采用矩阵分块方法获得关于此映射的几个... 为了推广算子代数中的基本理论,对一类非线性映射成为套代数上的可加中心化子的条件进行了研究。首先,基于Hilbert空间上的非平凡套定义与该套有关的套代数,并定义套代数上的一个非线性映射;其次,采用矩阵分块方法获得关于此映射的几个性质;最后,证明套代数上满足某种条件的非线性映射为可加中心化子,给出刻画该映射的具体形式。结果表明,套代数上满足某种条件的非线性映射为可加中心化子,且可完全刻画。研究结果推广了非线性映射成为套代数上可加中心化子的结论,丰富了算子代数拓扑结构的分类问题,为套代数上其他类型非线性映射问题的刻画提供了借鉴与参考。 展开更多
关键词 算子代数 中心化子 非线性映射 HILBERT空间 矩阵分块
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