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UNIFORM NORMAL STRUCTURE AND SOLUTIONS OF REICH’S OPEN QUESTION
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作者 曾六川 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第9期1204-1211,共8页
The open question raised by Reich is studied in a Banach space with uniform normal structure, whose norm is uniformly Gateaux differentiable. Under more suitable assumptions imposed on an asymptotically nonexpansive m... The open question raised by Reich is studied in a Banach space with uniform normal structure, whose norm is uniformly Gateaux differentiable. Under more suitable assumptions imposed on an asymptotically nonexpansive mapping, an affirmative answer to Reich' s open question is given. The results presented extend and improve Zhang Shisheng' s recent ones in the following aspects : (i) Zhang' s stronger condition that the sequence of iterative parameters converges to zero is removed; (ii) Zhang' s stronger assumption that the asymptotically nonexpansive mapping has a fixed point is removed; (iii) Zhang' s stronger condition that the sequence generated by the Banach Contraction Principle is strongly convergent is also removed. Moreover, these also extend and improve the corresponding ones obtained previously by several authors including Reich, Shioji, Takahashi,Ueda and Wittmann. 展开更多
关键词 asymptotically nonexpansive mapping fixed point uniform normal structure uniformly CJateaux differentiable norm iterative approximation
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ON UNIFORM CONVERGENCE OF LINEAR OPERATORS ON THE PROBABILISTIC NORMED SPACE
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作者 魏勇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第7期655-663,共9页
In this paper, we introduced the notion of uniform convergence of the linear operators on the probabilistic nornied space, and the notion of probabilistic distance between the operators, which describes the above conv... In this paper, we introduced the notion of uniform convergence of the linear operators on the probabilistic nornied space, and the notion of probabilistic distance between the operators, which describes the above convergence completely. In terms of these notions, we obtained the essential features of the continuity of operators, and of the uniform convergence of operator sequences, and we also obtained the closure of continuity and complete continuity under the operation of the limit of uniform convergence. 展开更多
关键词 probabilistic continuity notions operators uniformLY TRIANGLE CONVERGENT normED SIMPLICITY SUBSET
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Double Transformed Tubal Nuclear Norm Minimization for Tensor Completion
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作者 TIAN Jialue ZHU Yulian LIU Jiahui 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第S01期166-174,共9页
Non-convex methods play a critical role in low-rank tensor completion for their approximation to tensor rank is tighter than that of convex methods.But they usually cost much more time for calculating singular values ... Non-convex methods play a critical role in low-rank tensor completion for their approximation to tensor rank is tighter than that of convex methods.But they usually cost much more time for calculating singular values of large tensors.In this paper,we propose a double transformed tubal nuclear norm(DTTNN)to replace the rank norm penalty in low rank tensor completion(LRTC)tasks.DTTNN turns the original non-convex penalty of a large tensor into two convex penalties of much smaller tensors,and it is shown to be an equivalent transformation.Therefore,DTTNN could take advantage of non-convex envelopes while saving time.Experimental results on color image and video inpainting tasks verify the effectiveness of DTTNN compared with state-of-the-art methods. 展开更多
关键词 double transformed tubal nuclear norm low tubal-rank non-convex optimization tensor factorization tensor completion
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MONOTONICITY IN ORLICZ-LORENTZ SEQUENCE SPACES EQUIPPED WITH THE ORLICZ NORM 被引量:1
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作者 巩万中 张道祥 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1577-1589,共13页
In Orlicz-Lorentz sequence space Aψ,w with the Orlicz norm, uniform monotonic- ity, points of upper local uniform monotonicity and lower local uniform monotonicity are characterized. Moreover, the monotonicity coeffi... In Orlicz-Lorentz sequence space Aψ,w with the Orlicz norm, uniform monotonic- ity, points of upper local uniform monotonicity and lower local uniform monotonicity are characterized. Moreover, the monotonicity coefficient in Aψ,w are discussed. 展开更多
关键词 Orlicz-Lorentz sequence space Orlicz norm point of upper (lower) local uni-form monotonicity uniform monotonicity monotone coefficient
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Research on infrared dim and small target detection algorithm based on low-rank tensor recovery
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作者 LIU Chuntong WANG Hao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期861-872,共12页
In order to rapidly and accurately detect infrared small and dim targets in the infrared image of complex scene collected by virtual prototyping of space-based downward-looking multiband detection,an improved detectio... In order to rapidly and accurately detect infrared small and dim targets in the infrared image of complex scene collected by virtual prototyping of space-based downward-looking multiband detection,an improved detection algorithm of infrared small and dim target is proposed in this paper.Firstly,the original infrared images are changed into a new infrared patch tensor mode through data reconstruction.Then,the infrared small and dim target detection problems are converted to low-rank tensor recovery problems based on tensor nuclear norm in accordance with patch tensor characteristics,and inverse variance weighted entropy is defined for self-adaptive adjustment of sparseness.Finally,the low-rank tensor recovery problem with noise is solved by alternating the direction method to obtain the sparse target image,and the final small target is worked out by a simple partitioning algorithm.The test results in various spacebased downward-looking complex scenes show that such method can restrain complex background well by virtue of rapid arithmetic speed with high detection probability and low false alarm rate.It is a kind of infrared small and dim target detection method with good performance. 展开更多
关键词 complex scene infrared block tensor tensor kernel norm low-rank tensor restoration weighted inverse entropy alternating direction method
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Projective Tensor Products of <i>C*</i>-Algebras
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作者 Ajay Kumar Vandana Rajpal 《Advances in Pure Mathematics》 2014年第5期176-188,共13页
For C*-algebras A and B, the constant involved in the canonical embedding of into is shown to be . We also consider the corresponding operator space version of this embedding. Ideal structure of is obtained in case A ... For C*-algebras A and B, the constant involved in the canonical embedding of into is shown to be . We also consider the corresponding operator space version of this embedding. Ideal structure of is obtained in case A or B has only finitely many closed ideals. 展开更多
关键词 Banach SPACE PROJECTIVE tensor norm Operator SPACE PROJECTIVE tensor norm
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Parameter Estimation of Multiple Frequency-Hopping Signals Based on Space-Time-Frequency Analysis by Atomic Norm Soft Thresholding with Missing Observations
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作者 Hongbin Wang Bangning Zhang +2 位作者 Heng Wang Binbin Wu Daoxing Guo 《China Communications》 SCIE CSCD 2022年第7期135-151,共17页
In this paper,we address the problem of multiple frequency-hopping(FH)signal parameters estimation in the presence of random missing observations.A space-time matrix with random missing observations is acquired by a u... In this paper,we address the problem of multiple frequency-hopping(FH)signal parameters estimation in the presence of random missing observations.A space-time matrix with random missing observations is acquired by a uniform linear array(ULA).We exploit the inherent incomplete data processing capability of atomic norm soft thresholding(AST)to analyze the space-time matrix and complete the accurate estimation of the hopping time and frequency of the received FH signals.The hopping time is obtained by the sudden changes of the spatial information,which is implemented as the boundary to divide the time domain signal so that each segment of the signal is a superposition of time-invariant multiple components.Then,the frequency of multiple signal components can be estimated precisely by AST within each segment.After obtaining the above two parameters of the hopping time and the frequency of signals,the direction of arrival(DOA)can be directly calculated by them,and the network sorting can be realized.Results of simulation show that the proposed method is superior to the existing technology.Even when a large portion of data observations is missing,as the number of array elements increases,the proposed method still achieves acceptable accuracy of multi-FH signal parameters estimation. 展开更多
关键词 frequency hopping parameter estimation missing observations atomic norm soft thresholding uniform linear array
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A Study of Caristi’s Fixed Point Theorem on Normed Space and Its Applications
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作者 Md. Abdul Mannan Moqbul Hossain +1 位作者 Halima Akter Samiran Mondal 《Advances in Pure Mathematics》 2021年第3期169-179,共11页
In this work, we will discuss Caristi’s fixed point theorem for mapping results introduced in the setting of normed spaces. This work is a generalization of the classical Caristi’s fixed point theorem. Also, Caristi... In this work, we will discuss Caristi’s fixed point theorem for mapping results introduced in the setting of normed spaces. This work is a generalization of the classical Caristi’s fixed point theorem. Also, Caristi’s type of fixed points theorem was partial discussed in Reich, Mizoguchi and Takahashi’s and Amini-Harandi’s results, we developed ideas that many known fixed point theorems can easily be derived from the Caristi theorem. 展开更多
关键词 norm uniformITY Mizoguchi and Takahashi’s Rich’s Problem Caristi’s Fixed Point Theorem Strong and Weak Contraction SEMI-CONTINUOUS
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Parallel Active Subspace Decomposition for Tensor Robust Principal Component Analysis
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作者 Michael K.Ng Xue-Zhong Wang 《Communications on Applied Mathematics and Computation》 2021年第2期221-241,共21页
Tensor robust principal component analysis has received a substantial amount of attention in various fields.Most existing methods,normally relying on tensor nuclear norm minimization,need to pay an expensive computati... Tensor robust principal component analysis has received a substantial amount of attention in various fields.Most existing methods,normally relying on tensor nuclear norm minimization,need to pay an expensive computational cost due to multiple singular value decompositions at each iteration.To overcome the drawback,we propose a scalable and efficient method,named parallel active subspace decomposition,which divides the unfolding along each mode of the tensor into a columnwise orthonormal matrix(active subspace)and another small-size matrix in parallel.Such a transformation leads to a nonconvex optimization problem in which the scale of nuclear norm minimization is generally much smaller than that in the original problem.We solve the optimization problem by an alternating direction method of multipliers and show that the iterates can be convergent within the given stopping criterion and the convergent solution is close to the global optimum solution within the prescribed bound.Experimental results are given to demonstrate that the performance of the proposed model is better than the state-of-the-art methods. 展开更多
关键词 Principal component analysis Low-rank tensors Nuclear norm minimization Active subspace decomposition Matrix factorization
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基于低秩张量补全的非侵入式负荷监测缺失数据修复方法 被引量:2
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作者 杨挺 叶芷杉 +1 位作者 徐嘉成 杨振宁 《电网技术》 EI CSCD 北大核心 2024年第1期394-404,共11页
非侵入式负荷监测技术(non-intrusive load monitoring,NILM)作为实现智能电网用户侧细粒度感知的重要手段,有助于实现需求响应、提高“源-网-荷”互动效率和优化用能,助力实现“30·60目标”。高质量的量测信息是数据驱动型NILM的... 非侵入式负荷监测技术(non-intrusive load monitoring,NILM)作为实现智能电网用户侧细粒度感知的重要手段,有助于实现需求响应、提高“源-网-荷”互动效率和优化用能,助力实现“30·60目标”。高质量的量测信息是数据驱动型NILM的基础,但由于数据采集装置故障、通道拥塞以及延时等都会导致数据缺失,尤其是严重的连续性缺失,由此造成非侵入式负荷监测与分解的精度下降,影响用户画像、需求响应等高级应用。因此,针对该问题,提出了一种基于CP分解的正则化低秩张量补全的量测数据缺失修复方法。算法突破传统单维数据处理局限,对NILM多维量测数据构建了三阶观测张量,从而利用数据内部时序关联性和参量维度间电气关联性进行正则化低秩张量补全。并针对每次核范数计算过程中奇异值分解计算量过大问题,采用基于CP因子矩阵分解的核范数计算降低计算量,减少计算时长,并证明了变换的等效性。最后基于NILM公开数据集iAWE进行了实验,实验结果表明所提出的方法可以提高数据修复精度,在高缺失率和连续缺失情况下仍能有较好地补全效果,并且通过非侵入式负荷分解实验证明其可有效提高分解精度,对智能电网提升细粒度感知能力具有良好的实际意义。 展开更多
关键词 数据修复 低秩张量 核范数 非侵入式负荷监测 连续性缺失
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改进非凸估计与非对称时空正则化的红外小目标检测方法
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作者 胡亮 杨德贵 +1 位作者 赵党军 张俊超 《国防科技大学学报》 EI CAS CSCD 北大核心 2024年第3期180-194,共15页
针对复杂背景下的红外小目标检测,在非对称时空正则化约束的非凸张量低秩估计算法基础上,提出了一种新的核范数估计方法代替原算法中的估计方法。提出基于结构张量与多结构元顶帽(Top-Hat)滤波的自适应权重张量对目标张量进行约束,增强... 针对复杂背景下的红外小目标检测,在非对称时空正则化约束的非凸张量低秩估计算法基础上,提出了一种新的核范数估计方法代替原算法中的估计方法。提出基于结构张量与多结构元顶帽(Top-Hat)滤波的自适应权重张量对目标张量进行约束,增强目标张量稀疏性的同时抑制其中残存的强边缘结构。实验结果表明,所提改进算法能够更好地消除图像中强边缘结构对检测结果的影响,在保证检测率的情况下,较原算法具有更低的虚警率。 展开更多
关键词 红外小目标检测 张量恢复 张量核范数 多结构元Top-Hat滤波
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一类非线性超图的Estrada指数
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作者 范益政 郑剑 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第6期1-8,共8页
研究一类非线性超图:太阳花型超图的Estrada指数.首先,给出了太阳花超图SH^(m)_(n,q)在q=2的迹的显式表达,并刻画超图在局部结构变化时迹的扰动.利用该扰动结果,确定了在给定边数的太阳花型超图中Estrada指数达到最大的唯一超图.
关键词 一致超图 张量 Estrada指数 太阳花型超图
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k一致超图的α谱极值结果
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作者 朱忠熏 王缘 张萌 《中南民族大学学报(自然科学版)》 CAS 2024年第4期573-576,共4页
设F是一个简单图,如果Berge F的每条边均由超边替换F中的边而得到,则Berge F为超图.超图G如果不包含子超图Berge F,则G是Berge F-free的.为此,基于Aα张量研究具有特殊结构的线性一致超图的谱-Turán-问题,分别证明了Berge C4-free... 设F是一个简单图,如果Berge F的每条边均由超边替换F中的边而得到,则Berge F为超图.超图G如果不包含子超图Berge F,则G是Berge F-free的.为此,基于Aα张量研究具有特殊结构的线性一致超图的谱-Turán-问题,分别证明了Berge C4-free和围长至少为5的线性一致超图的α谱极值. 展开更多
关键词 k一致超图 Aα张量 α谱半径
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张量学习诱导的多视图谱聚类 被引量:1
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作者 陈曼笙 蔡晓莎 +3 位作者 林家祺 王昌栋 黄栋 赖剑煌 《计算机学报》 EI CAS CSCD 北大核心 2024年第1期52-68,共17页
现有的方法将通过张量奇异值分解(t-SVD)正则化的低秩表示应用到多视图子空间聚类中,取得了令人印象深刻的聚类性能.然而,它们都具有以下两个共同的缺点:(1)他们专注于探索样本之间的关系以构建表征,然后将其堆叠为张量,其计算复杂度至... 现有的方法将通过张量奇异值分解(t-SVD)正则化的低秩表示应用到多视图子空间聚类中,取得了令人印象深刻的聚类性能.然而,它们都具有以下两个共同的缺点:(1)他们专注于探索样本之间的关系以构建表征,然后将其堆叠为张量,其计算复杂度至少为O(n2logn);(2)他们总是直接在整合的表征上运行标准的谱聚类算法,而忽略了不同表征对最终聚类结果的先验知识.为了解决这些问题,本文提出了一种新颖的张量学习诱导的多视图谱聚类(TLIMSC)方法,其中同时探索了空间聚类结构和互补信息.具体来说,该方法将关联样本和簇关系的多视图谱嵌入表示堆叠成张量,计算复杂度最终变为O(n logn).然后,将学习到的带有不同自适应置信度的表征与最终的一致聚类结果联系起来.在五个数据集上的广泛实验证明了TLIMSC所具有的有效性和高效性. 展开更多
关键词 多视图聚类 加权张量核范数 谱嵌入表征 自适应置信度
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基于加权张量低秩约束的多视图谱聚类 被引量:1
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作者 刘思慧 高全学 +1 位作者 宋伟 谢德燕 《计算机工程》 CSCD 北大核心 2024年第1期129-137,共9页
现有基于图的多视图聚类方法通常难以同时考虑不同视图的潜在高阶相关信息和每个视图内的全局几何结构,导致聚类性能受限。为此,提出一种基于加权张量低秩约束的多视图谱聚类方法(WTLR-MSC)。根据多视图数据构建概率转移矩阵,将所有的... 现有基于图的多视图聚类方法通常难以同时考虑不同视图的潜在高阶相关信息和每个视图内的全局几何结构,导致聚类性能受限。为此,提出一种基于加权张量低秩约束的多视图谱聚类方法(WTLR-MSC)。根据多视图数据构建概率转移矩阵,将所有的概率转移矩阵构建为三阶张量,并借助鲁棒主成分分析思想将其分解为目标张量和误差张量。使用加权张量核范数约束目标张量的旋转张量,利用奇异值先验信息准确挖掘多视图数据的潜在高阶相关信息,并利用核范数约束目标张量的每个正切片以刻画每个视图内的全局几何结构。基于此建立数学模型,并设计有效的求解算法。在BBCSport、BBC4View、COIL20、UCI Digits 4个常用数据集上的实验结果表明,WTLR-MSC较ERLRT、MCA~2M、MGL-WTNN等聚类方法的性能有显著提升,准确率、标准化互信息、F1值、精确率、召回率相较于次优方法最高提升约1.3、1.0、1.2、1.6和0.8个百分点,大幅增强了多视图聚类的稳健性。 展开更多
关键词 加权张量核范数 谱聚类 多视图谱聚类 图学习 张量低秩
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绿色金融标准的法治转型 被引量:3
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作者 陈波 《东方法学》 CSSCI 北大核心 2024年第2期189-200,共12页
绿色金融标准作为一项治理工具,具有明确的统一性和规范性作用,是绿色金融可持续发展的重要支柱。随着双碳目标的确立和绿色投融资需求的深化,以标准化增强治理效能成为绿色金融业重要共识和绿色金融监管部门优先选项。作为政府监管、... 绿色金融标准作为一项治理工具,具有明确的统一性和规范性作用,是绿色金融可持续发展的重要支柱。随着双碳目标的确立和绿色投融资需求的深化,以标准化增强治理效能成为绿色金融业重要共识和绿色金融监管部门优先选项。作为政府监管、行业自律和社会治理的评价基准,绿色金融标准的法治化应从标准化和法治化的互动出发,从标准的制定主体、调整范围、法律效力和制定程序四个层面进行全面检视。为了完善绿色金融标准制度体系,需在法治化视野下廓清绿色金融标准的内涵与外延,确立价值目标兼容、多元维度拓展、适用逻辑协同和法治程序保障等有效运行机制。 展开更多
关键词 绿色金融 标准 统一性 规范性 法治转型 法律效力
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基于对数全变分极小化的张量补全
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作者 卢丹 王建军 《宁夏大学学报(自然科学版)》 CAS 2024年第1期1-8,共8页
在张量补全问题中,低秩性与局部光滑性是被高频使用的先验信息,因此有许多与其相关的研究.而且为了更精确地恢复图像,低秩性正则与编码局部光滑性的全变分正则往往会被以简单加权组合的方式引入相关模型.但许多真实图像往往同时具有低... 在张量补全问题中,低秩性与局部光滑性是被高频使用的先验信息,因此有许多与其相关的研究.而且为了更精确地恢复图像,低秩性正则与编码局部光滑性的全变分正则往往会被以简单加权组合的方式引入相关模型.但许多真实图像往往同时具有低秩性与局部光滑性先验信息.此外,在这些模型中张量核范数常被用于挖掘低秩性先验,但它平均地缩小所有奇异值,从而不能很好地保留图像信息.为此,提出了张量对数相关全变分(TLOGCTV)正则,其中使用了张量对数范数而不是核范数,从而更好地挖掘低秩先验信息,同时,使用全变分刻画局部光滑性先验信息.而且相较于简单加权组合方式引入正则的模型,所提出的模型仅需要一个平衡参数.随后基于该正则项建立了相应的张量补全模型,并且给出该模型的优化求解算法.在多光谱与高光谱上的一系列实验验证了模型的有效性. 展开更多
关键词 张量补全 张量对数范数 非凸全变分
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极小模原理在一类四阶全对称张量不等式中的应用
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作者 龚一帆 段德园 李虹 《云南师范大学学报(自然科学版)》 2024年第4期15-20,共6页
研究了四阶全对称张量的极小模张量,得到了其极小模张量和极小模的完整分类表达式,并证明了其极小模张量与trace-free分解的等价关系.进一步,利用极小模的非负性证明了在单位球∑^(n+1)中任意的一个极小超曲面上M^(n)上,|▽^(2)h|^(2)≥... 研究了四阶全对称张量的极小模张量,得到了其极小模张量和极小模的完整分类表达式,并证明了其极小模张量与trace-free分解的等价关系.进一步,利用极小模的非负性证明了在单位球∑^(n+1)中任意的一个极小超曲面上M^(n)上,|▽^(2)h|^(2)≥3/2[S×trh^(4)+n×S-(trh^(3))^(2)-2×S^(2)]+3S(S-n)^(2)/2(n+4),并发现其等号成立时M^(n)包含了∑^(n+1)中所有圆心是球心的大圆及其部分和Clifford环∑^(k)(√k/n)×∑^(n-k)(√n-k/n). 展开更多
关键词 极小模原理 张量的trace-free分解 极小超曲面 Clifford环
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张量环分解和空谱全变分的高光谱图像恢复算法
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作者 陈千 罗显康 +1 位作者 谢巧玉 李霞 《宜宾学院学报》 2024年第12期21-28,共8页
高光谱图像在采集和转换中会受到各种污染,目前在Tucker或CP上进行的多数去除噪声算法会改变信号固有的结构,对张量秩的最优估计非常困难.为此,提出基于张量环分解和空间光谱全变分的高光谱图像恢复模型:利用张量环分解的张量核范数和... 高光谱图像在采集和转换中会受到各种污染,目前在Tucker或CP上进行的多数去除噪声算法会改变信号固有的结构,对张量秩的最优估计非常困难.为此,提出基于张量环分解和空间光谱全变分的高光谱图像恢复模型:利用张量环分解的张量核范数和空间光谱全变分来约束低秩,更好地探索全局空间结构和相邻波段的频谱相关性,并利用增广拉格朗日算法求解此模型.数值实验表明,模型去除噪声后的图像清晰,PSNR、SSIM和FSIM三个指标均优于现有算法. 展开更多
关键词 张量核范数 高光谱图像 张量环分解 空间光谱全变分
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四元数矩阵方程(A_(1)XB_(1),…,A_(k)XB_(k))=(C_(1),…,C_(k))的极小范数最小二乘Toeplitz解
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作者 石俊岭 李莹 +2 位作者 王涛 张东惠 邱新 《兰州理工大学学报》 CAS 北大核心 2024年第1期152-157,共6页
基于四元数矩阵实表示,结合矩阵H-表示和矩阵半张量积提出一种求解四元数矩阵方程(A_(1)XB_(1),…,A_(k)XB_(k))=(C_(1),…,C_(k))的极小范数最小二乘Toeplitz解的有效方法,给出该四元数矩阵方程存在Toeplitz解的充要条件及通解表达式.... 基于四元数矩阵实表示,结合矩阵H-表示和矩阵半张量积提出一种求解四元数矩阵方程(A_(1)XB_(1),…,A_(k)XB_(k))=(C_(1),…,C_(k))的极小范数最小二乘Toeplitz解的有效方法,给出该四元数矩阵方程存在Toeplitz解的充要条件及通解表达式.给出数值算法并通过算例分别从误差与计算时间两个方面验证该方法的有效性. 展开更多
关键词 四元数矩阵方程 矩阵半张量积 极小范数最小二乘Toeplitz解 实表示 H-表示
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