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THE COAPPROXIMATION IN LINEAR SPACES 被引量:1
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作者 Son Wenhua Dalian University of Technology,China 《Analysis in Theory and Applications》 1993年第4期55-65,共11页
In this paper,we investigate the properties of strongly coapproximation in normed linear spaces and lo- cally,convex spaces.The relations between strongly coapproximation and strongly unique approximation and of the f... In this paper,we investigate the properties of strongly coapproximation in normed linear spaces and lo- cally,convex spaces.The relations between strongly coapproximation and strongly unique approximation and of the f-coapproximation and f-approximation,are also considered. 展开更多
关键词 TH THE COAPPROXIMATION IN linear spaceS
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CHARACTERIZATION OF BEST APPROXIMATIONS IN METRIC LINEAR SPACES
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作者 Sizwe Mabizela 《Analysis in Theory and Applications》 2003年第2期121-129,共9页
Let (X,d) be a real metric linear space, with translation-invariant metric d and C a linear subspace of X. In this paper we use functionals in the Lipschitz dual of X to characterize those elements of G which are best... Let (X,d) be a real metric linear space, with translation-invariant metric d and C a linear subspace of X. In this paper we use functionals in the Lipschitz dual of X to characterize those elements of G which are best approximations to elements of X.We also give simultaneous characterization of elements of best approximation and also consider elements of ε-approximation. 展开更多
关键词 metric linear space Lipschitz dual best approximation metric projection proximinal set Chebyshev set ε-approximation
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The Related Properties of Generalized Orthogonal Group in Specific Normed Linear Spaces
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作者 Siyuan Wu 《Journal of Applied Mathematics and Physics》 2022年第1期1-10,共10页
Firstly, in the general normed linear space, the concepts of generalized isosceles orthogonal group, generalized Birkhoff orthogonal group, generalized Roberts orthogonal group, strong Birkhoff orthogonal group and ge... Firstly, in the general normed linear space, the concepts of generalized isosceles orthogonal group, generalized Birkhoff orthogonal group, generalized Roberts orthogonal group, strong Birkhoff orthogonal group and generalized orthogonal basis are introduced. Secondly, the conclusion that any two nonzero generalized orthogonal groups must be linearly independent group is proven. And the existence of nonzero generalized orthogonal group and its linear correlation are discussed preliminarily, as well as some related properties of nonempty generalized orthogonal group in specific normed linear space namely the <em>l<sub>p</sub></em> space. 展开更多
关键词 Normed linear space Generalized Orthogonal Group Generalized Birkhoff Orthogonal Group Generalized Isosceles Orthogonal Group Generalized Roberts Orthogonal Group
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CHEBYSHEV CENTERS PROXIMINALITY AND FARTHEST POINTS IN STRONG NORMED ALMOST LINEAR SPACES
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作者 Geetha S. Rao T. L. Bhaskaramurthi 《Analysis in Theory and Applications》 1997年第4期99-111,共13页
Some results from the theory of best (or best simultaneous) approximation in a narmed linear space have been extended to a normed almost linear space [strong normed almost linear space].
关键词 CHEBYSHEV CENTERS PROXIMINALITY AND FARTHEST POINTS IN STRONG NORMED ALMOST linear spaceS
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《Metric Linear Spaces》的两点注记
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作者 王见勇 《常熟高专学报》 2002年第2期13-16,共4页
指出StefanRolewicz先生的名著《MetricLinearSpaces》中的三个定理的证明错误 。
关键词 度量线性空间 σ-有限测度空间 连续嵌入 实心F*-空间 最大不友好 凹性模
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Computational Analysis for Solving the Linear Space-Fractional Telegraph Equation
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作者 Zaki Mrzog Alaofi Talaat Sayed El-Danaf +1 位作者 Adel Hadhoud Silvestru Sever Dragomir 《Open Journal of Modelling and Simulation》 2022年第3期267-282,共16页
Over the last few years, there has been a significant increase in attention paid to fractional differential equations, given their wide array of applications in the fields of physics and engineering. The recent develo... Over the last few years, there has been a significant increase in attention paid to fractional differential equations, given their wide array of applications in the fields of physics and engineering. The recent development of using fractional telegraph equations as models in some fields (e.g., the thermal diffusion in fractal media) has heightened the importance of examining the method of solutions for such equations (both approximate and analytic). The present work is designed to serve as a valuable contribution to work in this field. The key objective of this work is to propose a general framework that can be used to guide quadratic spline functions in order to create a numerical method for obtaining an approximation solution using the linear space-fractional telegraph equation. Additionally, the Von Neumann method was employed to measure the stability of the analytical scheme, which showed that the proposed method is conditionally stable. What’s more, the proposal contains a numerical example that illustrates how the proposed method can be implemented practically, whilst the error estimates and numerical stability results are discussed in depth. The findings indicate that the proposed model is highly effective, convenient and accurate for solving the relevant problems and is suitable for use with approximate solutions acquired through the two-dimensional differential transform method that has been developed for linear partial differential equations with space- and time-fractional derivatives. 展开更多
关键词 Fractional Differential Equations Quadratic Spline Functions linear space-Fractional Telegraph Equation Von Neumann Stability
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k-MAJOR ORDER IN REAL INFINITE-DIMENSIONAL LINEAR SPACE AND ITS APPLICATION
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作者 Lu JingkuiDept.of Basic Knowledge,Shanghai Light Industry College,Shanghai 2 0 0 4 33. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第3期302-306,共5页
In this paper,the k major cone and strict k major cone in real infinite dimensional linear space are introduced,through which the k major order is defined,and their properties are also discussed.Therefore,with the ... In this paper,the k major cone and strict k major cone in real infinite dimensional linear space are introduced,through which the k major order is defined,and their properties are also discussed.Therefore,with the help of them any two elements in real infinite dimensional linear space can be compared. 展开更多
关键词 Real infinite dimensional linear space k major cone k major order.
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Angles of Norm ed Linear Spaces and Characterizations of Inner Product Spaces
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作者 郑永爱 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第1期70-73, ,共4页
In [1],a family of angles are defined in normed linear spaces. In this paper,it is shown that if anyone of the angles satisfies certain euclidean triangle congruence properties,the space must be an inner product space.
关键词 赋范线性空间 内积空间 角和线性空间
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Space Topologies and Their Dual Space Topologies for Conventional Functional Space Topologies
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作者 Mahjoub A. Elamin 《Journal of Applied Mathematics and Physics》 2024年第3期778-804,共27页
In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topo... In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topological vector spaces and it is in this context that we have chosen to present this work. We are interested in the topology of its spaces and in the topologies of their dual spaces. The first part, we presented the fundamental topological properties of topological vector spaces. The second part, we studied Frechet spaces and particularly the space S(R<sup>n</sup>) of functions of class C<sup>∞ </sup>on R<sup>n</sup> which are as well as all their rapidly decreasing partial derivatives. We have also studied its dual S'(Rn</sup>) the space of tempered distributions. The last part aims to define a topological structure on an increasing union of Frechet spaces called inductive limit of Frechet spaces. We study in particular the space D(Ω) of functions of class C<sup>∞</sup> with compact supports on Ω as well as its dual D' (Ω) the space distributions over the open set Ω. 展开更多
关键词 linear Forms Dual spaces Frechet spaces Partial Derivatives DISTRIBUTIONS Topological Structure Weak Topology Strong Topology
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Finite Line-transitive Linear Spaces:Theory and Search Strategies 被引量:1
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作者 Anton BETTEN Anne DELANDTSHEER +3 位作者 Maska LAW Alice C. NIEMEYER Cheryl E. PRAEGER Shenglin ZHOU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第9期1399-1436,共38页
The paper summarises existing theory and classifications for finite line-transitive linear spaces, develops the theory further, and organises it in a way that enables its effective application. The starting point is a... The paper summarises existing theory and classifications for finite line-transitive linear spaces, develops the theory further, and organises it in a way that enables its effective application. The starting point is a theorem of Camina and the fifth author that identifies three kinds of line-transitive automorphism groups of linear spaces. In two of these cases the group may be imprimitive on points, that is, the group leaves invariant a nontrivial partition of the point set. In the first of these cases the group is almost simple with point-transitive simple socle, and may or may not be point-primitive, while in the second case the group has a non-trivial point-intransitive normal subgroup and hence is definitely point-imprimitive. The theory presented here focuses on point-imprimitive groups. As a non-trivial application a classification is given of the point-imprimitive, line-transitive groups, and the corresponding linear spaces, for which the greatest common divisor gcd(k, v - 1) ≤ 8, where v is the number of points, and k is the line size. Motivation for this classification comes from a result of Weidong Fang and Huffing Li in 1993, that there are only finitely many non-trivial point-imprimitive, linetransitive linear spaces for a given value of gcd(k, v - 1). The classification strengthens the classification by Camina and Mischke under the much stronger restriction k ≤ 8: no additional examples arise. The paper provides the backbone for future computer-based classifications of point-imprimitive, line- transitive linear spaces with small parameters. Several suggestions for further investigations are made. 展开更多
关键词 linear space LINE-TRANSITIVE automorphism group combinatorial design combinatorial search algorithm
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Line-primitive Linear Spaces with Fang-Li Parameter gcd(k,r) at Most 12 被引量:1
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作者 Sheng Lin ZHOU Yan Bo MA Wei Dong FANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2011年第4期657-670,共14页
Let G be a subgroup of the automorphism group of a non-trivial finite linear space $. In this paper we prove that if G is line-primitive with Fang-Li parameter gcd(k, r) = 11 and 12, then G is also point-primitive. ... Let G be a subgroup of the automorphism group of a non-trivial finite linear space $. In this paper we prove that if G is line-primitive with Fang-Li parameter gcd(k, r) = 11 and 12, then G is also point-primitive. This extends the results of Fang and Li (1993) and Li and Liu (2001) which combined gives the result for gcd(k,r) ≤ 10. 展开更多
关键词 Finite linear spaces line-primitive point-imprimitive
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t-Singular Linear Spaces
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作者 Jun Guo Fenggao Li Kaishun Wang 《Algebra Colloquium》 SCIE CSCD 2016年第2期227-238,共12页
As a generalization of singular linear spaces, we introduce the concept of t-singular linear spaces, make some anzahl formulas of subspaces, and determine the suborbits of t-singular linear groups.
关键词 t-singular linear space t-singular linear group suborbit
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从Place连接Space助推“机械原理”一流课程建设
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作者 仝美娟 解妙霞 耿素花 《教育教学论坛》 2023年第30期161-164,共4页
基于教学实践,从教学内容、教学组织和双向评价这三个关键维度出发,分别在先进理论和现代设计方法、大规模在线教育和工程实践及教师评价“学”的过程和学生评价“教”的过程等重要方向建立连接,使课程体系从有限容量的线性place占位扩... 基于教学实践,从教学内容、教学组织和双向评价这三个关键维度出发,分别在先进理论和现代设计方法、大规模在线教育和工程实践及教师评价“学”的过程和学生评价“教”的过程等重要方向建立连接,使课程体系从有限容量的线性place占位扩展到大容量现代化教学的多方向space占位。建设结果表明,多方向的space课程体系既能解决学生学习过程中的主动性、积极性问题,又能助推课程自身迭代,促使“机械原理”始终处于一流课程的领先地位。 展开更多
关键词 教学组织 双向评价 线性place 多向space
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Almost simple groups with socle ^3D_4(q)act on finite linear spaces 被引量:8
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作者 LIU Weijun, DAI Shaojun & GONG Luozhong School of Mathematics, Central South University, Changsha 410075, China Department of Mathematics, Hunan University of Science and Engineering, Yongzhou 425006, China 《Science China Mathematics》 SCIE 2006年第12期1768-1776,共9页
After the classification of flag-transitive linear spaces,attention has now turned to line-transitive linear spaces.Such spaces are first divided into the point-imprimitive and the point-primitive,the first class is u... After the classification of flag-transitive linear spaces,attention has now turned to line-transitive linear spaces.Such spaces are first divided into the point-imprimitive and the point-primitive,the first class is usually easy by the theorem of Delandtsheer and Doyen.The primitive ones are now subdivided,according to the O'Nan-Scotte theorem and some further work by Camina,into the socles which are an elementary abelian or non-abelian simple.In this paper,we consider the latter.Namely,T ≤ G ≤ Aut(T) and G acts line-transitively on finite linear spaces,where T is a non-abelian simple.We obtain some useful lemmas.In particular,we prove that when T is isomorphic to 3D4(q),then T is line-transitive,where q is a power of the prime p. 展开更多
关键词 line-transitive linear space automorphism almost simple group.
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Solvable line-transitive automorphism groups of finite linear spaces 被引量:5
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作者 刘伟俊 李慧陵 《Science China Mathematics》 SCIE 2000年第10期1009-1013,共5页
Let S be a finite linear space, and let G be a group of automorphisms of S. If G is soluble and line-transitive, then for a given k but a finite number of pairs of ( S, G), S has v= pn points and G≤AΓ L(1,pn).
关键词 linear space LINE-TRANSITIVE AUTOMORPHISM SOLVABLE group.
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Smoothing methods based on coordinate transformation in a linear space and application in airfoil aerodynamic design optimization 被引量:3
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作者 WANG Chao GAO Zheng Hong +2 位作者 HUANG Jiang Tao ZHAO Ke LI Jing 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第2期297-306,共10页
In detailed aerodynamic design optimization,a large number of design variables in geometry parameterization are required to provide sufficient flexibility and obtain the potential optimum shape.However,with the increa... In detailed aerodynamic design optimization,a large number of design variables in geometry parameterization are required to provide sufficient flexibility and obtain the potential optimum shape.However,with the increasing number of design variables,it becomes difficult to maintain the smoothness on the surface which consequently makes the optimization process progressively complex.In this paper,smoothing methods based on B-spline functions are studied to improve the smoothness and design efficiency.The wavelet smoothing method and the least square smoothing method are developed through coordinate transformation in a linear space constructed by B-spline basis functions.In these two methods,smoothing is achieved by a mapping from the linear space to itself such that the design space remains unchanged.A design example is presented where aerodynamic optimization of a supercritical airfoil is conducted with smoothing methods included in the optimization loop.Affirmative results from the design example confirm that these two smoothing methods can greatly improve quality and efficiency compared with the existing conventional non-smoothing method. 展开更多
关键词 气动优化设计 平滑方法 线性空间 空气动力学设计 应用 翼型 B样条基函数 设计变量
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JOINT SPACE-FREQUENCY MULTIUSER SYMBOL DETECTOR FOR MC-CDMA SYSTEM WITH UNIFORM LINEAR ARRAY 被引量:3
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作者 Wu Xiaojun Yin Qinye Feng Aigang Zhao Zheng Zhang Jianguo(institute of Information Engineering, Xi’an Jinotong University, Xi’an 710049) 《Journal of Electronics(China)》 2002年第4期337-345,共9页
The MultiCarrier Code Division Multiple Access (MC-CDMA) scheme is promising for relieving capacity limit problems of Direct Sequence (DS-) CDMA systems due to serious InterChip Interference (ICI) and MultiUser Interf... The MultiCarrier Code Division Multiple Access (MC-CDMA) scheme is promising for relieving capacity limit problems of Direct Sequence (DS-) CDMA systems due to serious InterChip Interference (ICI) and MultiUser Interference (MUI) in high-data-rate wireless communication systems. In this paper, the Uniform Linear Array (ULA) is applied to the base station of macrocellular MC-CDMA systems in a frequency-selective fading channel environment. A joint space-frequency multiuser symbol sequence detector is developed for all active users within one macrocell without space-frequency channel estimation. Simultaneously, Directions-Of-Arrivals (DOAs) of all active users can also be estimated. By dividing the ULA into two identical overlapping subarrays, a specific auxiliary matrix is constructed, which includes both symbol sequence and DOA information of all active users. Then, based on the subspace method, performing the eigen decomposition on such auxiliary matrix, the closed-form solution of symbol sequences and DOAs for all active users can be obtained. In comparison with schemes based on channel estimation, our algorithm need not explicitly estimate the space-frequency channel for each active user,so it has lower computation complexity. Extensive computer simulations demonstrate the overall performance of this novel scheme. 展开更多
关键词 码分多址 多用户检测 选频衰落 均匀线性阵列 空号频率信道
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Krein space approach to robust H_∞ filtering for linear uncertain systems
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作者 Jin Feng Fei Yu +2 位作者 Na Yang Pengyu Zhang Wei Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第4期596-602,共7页
A novel Krein space approach to robust H∞ filtering for linear uncertain systems is developed. The parameter uncertainty, entering into both states and measurement equations, satisfies an energy-type constraint. Then... A novel Krein space approach to robust H∞ filtering for linear uncertain systems is developed. The parameter uncertainty, entering into both states and measurement equations, satisfies an energy-type constraint. Then a Krein space approach is used to tackle the robust H∞ filtering problem. To this end, a new Krein space formal system is designed according to the original sum quadratic constraint (SQC) without introducing any nonzero factors into it and, consequently, the estimate recursion is obtained through the filter gain in Krein space. Finally, a numerical example is given to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 linear uncertain system sum quadratic constraint(SQC) robust H∞ filtering Krein space linear estimation.
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Line-transitive point-imprimitive linear spaces with Fang-Li parameter gcd(k, r) at most ten
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作者 Haiyan GUAN Delu TIAN Shenglin ZHOU 《Frontiers of Mathematics in China》 SCIE CSCD 2012年第6期1095-1112,共18页
这份报纸是对 linetransitive 的分类的进一步的贡献有限线性空格。如果,我们证明那是一个重要有限线性空格以便 Fang-Li 参数 gcd (k, r ) 是 9 或 10,并且组 G Aut() 是线及物的并且 point-imprimitive,那么是 Desarguesian 射影... 这份报纸是对 linetransitive 的分类的进一步的贡献有限线性空格。如果,我们证明那是一个重要有限线性空格以便 Fang-Li 参数 gcd (k, r ) 是 9 或 10,并且组 G Aut() 是线及物的并且 point-imprimitive,那么是 Desarguesian 射影的飞机 PG (2, 9 ) 。 展开更多
关键词 线性空间 GCD 点本原 传递 投影平面
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A NEW PERTURBATION THEOREM FOR MOORE-PENROSE METRIC GENERALIZED INVERSE OF BOUNDED LINEAR OPERATORS IN BANACH SPACES 被引量:3
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作者 王紫 王玉文 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1619-1631,共13页
In this paper, we investigate a new perturbation theorem for the Moore-Penrose metric generalized inverses of a bounded linear operator in Banach space. The main tool in this paper is "the generalized Neumann lemma"... In this paper, we investigate a new perturbation theorem for the Moore-Penrose metric generalized inverses of a bounded linear operator in Banach space. The main tool in this paper is "the generalized Neumann lemma" which is quite different from the method in [12] where "the generalized Banach lemma" was used. By the method of the perturba- tion analysis of bounded linear operators, we obtain an explicit perturbation theorem and three inequalities about error estimates for the Moore-Penrose metric generalized inverse of bounded linear operator under the generalized Neumann lemma and the concept of stable perturbations in Banach spaces. 展开更多
关键词 Banach space bounded linear operator metric projection generalized inverse perturbation analysis Moore-Penrose quasi-additive
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