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内部算子与闭包算子的若干性质 被引量:9
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作者 姚卫 路玲霞 李生刚 《河北师范大学学报(自然科学版)》 CAS 2004年第3期234-236,共3页
研究了内部算子与闭包算子的一系列性质,得到如下结果:1)解决了有限完备链上内部算子和闭包算子的个数问题;2)证明了偏序集上的内部算子和闭包算子的图像是阶梯状的;3)建立了内部算子之集和闭包算子之集与某集合的幂集之间的序同构;4)... 研究了内部算子与闭包算子的一系列性质,得到如下结果:1)解决了有限完备链上内部算子和闭包算子的个数问题;2)证明了偏序集上的内部算子和闭包算子的图像是阶梯状的;3)建立了内部算子之集和闭包算子之集与某集合的幂集之间的序同构;4)找到了一个映射成为内部算子或闭包算子的等价刻画. 展开更多
关键词 内部算子 闭包算子 偏序集 BOOLE代数 序同构
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Central simple Poisson algebras 被引量:5
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作者 SU Yucai & XU XiaopingDepartment of Mathematics, Shanghai Jiaotong University, Shanghai 200030, China Institute of Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, China 《Science China Mathematics》 SCIE 2004年第2期245-263,共19页
Poisson algebras are fundamental algebraic structures in physics and symplectic geometry. However, the structure theory of Poisson algebras has not been well developed. In this paper, we determine the structure of the... Poisson algebras are fundamental algebraic structures in physics and symplectic geometry. However, the structure theory of Poisson algebras has not been well developed. In this paper, we determine the structure of the central simple Poisson algebras related to locally finite derivations, over an algebraically closed field of characteristic zero.The Lie algebra structures of these Poisson algebras are in general not finitely-graded. 展开更多
关键词 POISSON algebra locally-finite operator derivation finitely-graded ISOMORPHISM class.
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The Construction and Analysis of Linear Ring Spaces
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作者 Daniel A. Jaffa 《Advances in Pure Mathematics》 2024年第9期759-767,共9页
This paper proposes the novel algebraic structure of a linear ring space. A linear ring space is an order triad consisting of two rings, and a linear map between the two rings. The definition of quasi-linearity is dis... This paper proposes the novel algebraic structure of a linear ring space. A linear ring space is an order triad consisting of two rings, and a linear map between the two rings. The definition of quasi-linearity is discussed, in addition to the examination of properties and classifications of linear ring spaces. Particularly, the ring of holomorphic functions on a region of the complex plane is examined, and the manner in which it generates an iterated linear ring space under the complex derivative operator. This notion is then generalized to all rings with nth order linear and surjective operators. Basic operator theory regarding the classifications of linear ring maps is also covered. 展开更多
关键词 Ring Theory Group Theory Commutative algebra operator Theory Holomorphic Functions
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TOEPLITZ OPERATORS AND ALGEBRAS ON DIRICHLET SPACES 被引量:7
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作者 CAO GUANGFU Department of Mathematics, Sichuan University, Chengdu 610064, China. 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2002年第3期385-396,共12页
The automorphism group of the Toeplitz C^*- algebra, J(C^1), generated by Toeplitz op-erators with C^1-symbols on Dirichlet space D is discussed; the K0, K1-groups and the first cohomology group of J(C^1) are compute... The automorphism group of the Toeplitz C^*- algebra, J(C^1), generated by Toeplitz op-erators with C^1-symbols on Dirichlet space D is discussed; the K0, K1-groups and the first cohomology group of J(C^1) are computed. In addition, the author proves that the spectra of Toeplitz operators with C^1-symbols are always connected, and discusses the algebraic prop-erties of Toeplitz operators.In particular, it is proved that there is no nontrivial selfadjoint Toeplitz operator on D and Tψ^* = Tψ^- if and only if Tψ is a scalar operator. 展开更多
关键词 Dirichlet space Toeplitz operator Toeplitz algebra
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算子李代数g(G,M)[σ] 被引量:6
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作者 王春艳 李立 堵秀凤 《齐齐哈尔大学学报(自然科学版)》 2007年第6期60-63,共4页
构造了由算子构成的李代数g(G,M)[σ],然后讨论了算子李代数g(G,M)[σ]的代数结构。
关键词 顶点算子 李代数 向量空间 代数结构
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Getting pre-stack time migration travel times from the single square root operator 被引量:6
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作者 Liu Guofeng Liu Hong +1 位作者 Li Bo Meng Xiaohong 《Applied Geophysics》 SCIE CSCD 2009年第2期129-137,共9页
Improving the focusing capability of pre-stack time migration allows the imaged section to reflect structural characteristics, depth, and interface shape and it is a key step for the preparation of the initial depth m... Improving the focusing capability of pre-stack time migration allows the imaged section to reflect structural characteristics, depth, and interface shape and it is a key step for the preparation of the initial depth migration velocity model. The traditional symmetrical travel time equation is derived based on the assumption of a layered model. It is difficult to achieve the desired effect of focusing in media with strong lateral variation. The nonsymmetrical travel time equation based on Lie algebra and a pseudo-differential operator contains a lateral velocity derivative which can improve the focusing capability even in strongly lateral variable media and also the computation precision of the weight coefficients for relative amplitude preservation. Compared with the symmetrical methods, the nonsymmetrical method is more effective. In this paper, we describe several key steps of nonsymmetric pre-stack travel time calculation and present some test results using synthetic and real data. 展开更多
关键词 single square root operator travel time Lie algebra pseudo-differential operator
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Reducing Subspaces of Toeplitz Operators Induced by a Class of Non-analytic Monomials over the Unit Ball
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作者 Yan Yue SHI Bo ZHANG +1 位作者 Xu TANG Yu Feng LU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第7期1767-1777,共11页
In this paper,we describe the minimal reducing subspaces of Toeplitz operators induced by non-analytic monomials on the weighted Bergman spaces and Dirichlet spaces over the unit ball B_(2).It is proved that each mini... In this paper,we describe the minimal reducing subspaces of Toeplitz operators induced by non-analytic monomials on the weighted Bergman spaces and Dirichlet spaces over the unit ball B_(2).It is proved that each minimal reducing subspace M is finite dimensional,and if dim M≥3,then M is induced by a monomial.Furthermore,the structure of commutant algebra v(T_(w)N_(z)N):={M^(*)_(w)NM_(z)N,M^(*)_(z)NM_(w)N}′is determined by N and the two dimensional minimal reducing subspaces of(T_(w)N_(z)N.We also give some interesting examples. 展开更多
关键词 Reducing subspace operator-weighted shifts Toeplitz operator von Neumann algebra
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Coverage analysis for sensor networks based on Clifford algebra 被引量:4
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作者 XIE WeiXin CAO WenMing MENG Shan 《Science in China(Series F)》 2008年第5期460-475,共16页
The coverage performance is the foundation of information acquisition in distributed sensor networks. The previously proposed coverage work was mostly based on unit disk coverage model or ball coverage model in 2D or ... The coverage performance is the foundation of information acquisition in distributed sensor networks. The previously proposed coverage work was mostly based on unit disk coverage model or ball coverage model in 2D or 3D space, respectively. However, most methods cannot give a homogeneous coverage model for targets with hybrid types. This paper presents a coverage analysis approach for sensor networks based on Clifford algebra and establishes a homogeneous coverage model for sensor networks with hybrid types of targets. The effectiveness of the approach is demonstrated with examples. 展开更多
关键词 sensor network Clifford algebra coverage analysis rotation operator distance measure
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On the Supercyclicity and Hypercyclicity of the Operator Algebra 被引量:3
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作者 B.YOUSEFI H.REZAEI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第7期1221-1232,共12页
Let B(X) be the operator algebra for a separable infinite dimensional Hilbert space H, endowed with the strong operator topology or *-strong topology. We give sufficient conditions for a continuous linear mapping L... Let B(X) be the operator algebra for a separable infinite dimensional Hilbert space H, endowed with the strong operator topology or *-strong topology. We give sufficient conditions for a continuous linear mapping L : B(X) →B(X) to be supercyclic or ,-supercyclic. In particular our condition implies the existence of an infinite dimensional subspace of supercyclic vectors for a mapping T on H. Hypercyclicity of the operator algebra with strong operator topology was studied' by Chan and here we obtain an analogous result in the case of *-strong operator topology. 展开更多
关键词 operator algebra *-strong topology strong operator topology hypercyclicity criterion supercyclicity criterion
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Bimodules associated to vertex operator superalgebras 被引量:1
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作者 JIANG Wei JIANG CuiBo 《Science China Mathematics》 SCIE 2008年第9期1705-1725,共21页
Let V be a vertex operator superalgebra and m, n ∈ 1/2 ?+. We construct an A n (V)-A m (V)-bimodule A n,m (V) which characterizes the action of V from the level m subspace to level n subspace of an admissible V-modul... Let V be a vertex operator superalgebra and m, n ∈ 1/2 ?+. We construct an A n (V)-A m (V)-bimodule A n,m (V) which characterizes the action of V from the level m subspace to level n subspace of an admissible V-module. We also construct the Verma type admissible V-module from an A m (V)-module by using bimodules 展开更多
关键词 vertex operator algebra admissible module vertex operator superalgebra associative algebra BIMODULE 17B69
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A general mirror equivalence theorem for coset vertex operator algebras
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作者 Robert McRae 《Science China Mathematics》 SCIE CSCD 2024年第10期2237-2282,共46页
We prove a general mirror duality theorem for a subalgebra U of a simple conformal vertex algebra A and its commutant V=ComA(U).Specifically,we assume that A≌■_(i∈I)U_(i)■V_(i) as a U■V-module,where the U-modules... We prove a general mirror duality theorem for a subalgebra U of a simple conformal vertex algebra A and its commutant V=ComA(U).Specifically,we assume that A≌■_(i∈I)U_(i)■V_(i) as a U■V-module,where the U-modules Uiare simple and distinct and are objects of a semisimple braided ribbon category of Umodules,and the V-modules Viare semisimple and contained in a(not necessarily rigid) braided tensor category of V-modules.We also assume U=ComA(V).Under these conditions,we construct a braid-reversed tensor equivalence τ:u_(A)→v_(A),where u_(A)is the semisimple category of U-modules with simple objects Ui,i∈I,and v_(A)is the category of V-modules whose objects are finite direct sums of Vi.In particular,the V-modules Viare simple and distinct,and v_(A)is a rigid tensor category.As an application,we find a rigid semisimple tensor subcategory of modules for the Virasoro algebra at central charge 13+6p+6p^(-1),p∈Z_(≥2), which is braided tensor equivalent to an abelian 3-cocycle twist of the category of finite-dimensional sl2-modules.Consequently,the Virasoro vertex operator algebra at central charge 13+6p+6p^(-1)is the PSL_(2)(C)-fixed-point subalgebra of a simple conformal vertex algebra w(-p),analogous to the realization of the Virasoro vertex operator algebra at central charge 13-6p-6p^(-1)as the PSL_(2)(C)-fixed-point subalgebra of the triplet algebra W(p). 展开更多
关键词 vertex operator algebras coset conformal eld theory braid-reversed tensor equivalence Virasoro algebra
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定性代数的形式框架FAQA 被引量:2
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作者 陈见 石纯一 《计算机学报》 EI CSCD 北大核心 1995年第6期417-423,共7页
本文首先讨论了定性推理系统和定量推理系统的结构论述.进而给出了定性代数的一种形式框架FAQA,提出了定性、定量是不同层次观察结果的观点,并对定性(混合)结构进行了分析描述.FAQA框架是Williams等人工作理论上... 本文首先讨论了定性推理系统和定量推理系统的结构论述.进而给出了定性代数的一种形式框架FAQA,提出了定性、定量是不同层次观察结果的观点,并对定性(混合)结构进行了分析描述.FAQA框架是Williams等人工作理论上的完善及统一基础. 展开更多
关键词 定性推理 定性代数 定性论域 人工智能 FAQA
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Ergodic Hypothesis and Equilibrium Statistical Mechanics in the Quantum Mechanical World View 被引量:4
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作者 Shiro Ishikawa 《World Journal of Mechanics》 2012年第2期125-130,共6页
In this paper, we study and answer the following fundamental problems concerning classical equilibrium statistical mechanics: 1): Is the principle of equal a priori probabilities indispensable for equilibrium statisti... In this paper, we study and answer the following fundamental problems concerning classical equilibrium statistical mechanics: 1): Is the principle of equal a priori probabilities indispensable for equilibrium statistical mechanics? 2): Is the ergodic hypothesis related to equilibrium statistical mechanics? Note that these problems are not yet answered, since there are several opinions for the formulation of equilibrium statistical mechanics. In order to answer the above questions, we first introduce measurement theory (i.e., the theory of quantum mechanical world view), which is characterized as the linguistic turn of quantum mechanics. And we propose the measurement theoretical foundation of equili-brium statistical mechanics, and further, answer the above 1) and 2), that is, 1) is “No”, but, 2) is “Yes”. 展开更多
关键词 The Copenhagen Interpretation Probability operator algebra ERGODIC THEOREM Quantum and CLASSICAL Measurement Theory Liouville’s THEOREM The Law of INCREASING Entropy
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On K_(0)-groups of operator algebras on Banach spaces 被引量:4
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作者 ZHANG Yunnan ZHONG Huaijie SU Weigang 《Science China Mathematics》 SCIE 2006年第2期233-244,共12页
This paper merges some classifications of G-M-type Banach spaces simplifically, discusses the condition of K0(B(X)) = 0 for operator algebra B(X) on a Banach space X, and obtains a result to improve Laustsen's suf... This paper merges some classifications of G-M-type Banach spaces simplifically, discusses the condition of K0(B(X)) = 0 for operator algebra B(X) on a Banach space X, and obtains a result to improve Laustsen's sufficient condition, gives an example to show that X ≈ X2 is not a sufficient condition of K0(B(X)) = 0. 展开更多
关键词 Banach space operator Banach algebra K0-group.
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ADDITIVE MAPS ON SOME OPERATOR ALGEBRAS BEHAVING LIKE(α, β)-DERIVATIONS OR GENERALIZED(α, β)-DERIVATIONS AT ZERO-PRODUCT ELEMENTS 被引量:2
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作者 Hoger GHAHRAMANI 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1287-1300,共14页
Let A be a subalgebra of B(X) containing the identity operator I and an idempotent P. Suppose that α,β: A →A are ring epimorphisms and there exists some nest N on 2( such that α(P)(X) and β(P)(X) are ... Let A be a subalgebra of B(X) containing the identity operator I and an idempotent P. Suppose that α,β: A →A are ring epimorphisms and there exists some nest N on 2( such that α(P)(X) and β(P)(X) are non-trivial elements of N. Let A contain all rank one operators in AlgN and δ : A→ B(X) be an additive mapping. It is shown that, if δ is (α, β)-derivable at zero point, then there exists an additive (α, β)-derivation τ : A →β(X) such that δ(A) =τ(A) + α(A)δ(I) for all A∈A. It is also shown that if δ is generalized (α,β)-derivable at zero point, then δ is an additive generalized (α, β)-derivation. Moreover, by use of this result, the additive maps (generalized) (α,β)-derivable at zero point on several nest algebras, are also characterized. 展开更多
关键词 operator algebra nest algebra (α β)-derivation generalized (α β)-derivation
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关于中心化子的一类映射 被引量:5
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作者 崔云丽 张建华 《纺织高校基础科学学报》 CAS 2009年第1期25-28,共4页
X表示实数域或复数域F上的Banach空间,设M是X上的一个标准算子代数,I是M的单位元.证明了若可加映射φ:M→B(X)满足A∈M,非零实数m和n,有(m+n)φ(A2)-mAφ(A)-nφ(A)A∈FI.则ヨλ∈F,使得φ(A)=λA.
关键词 可加映射 中心化子 算子代数
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View Creation for Queriesin Object Oriented Databases
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作者 RajeshNarang K.D.Sharma 《Journal of Computer Science & Technology》 SCIE EI CSCD 1999年第4期349-362,共14页
A view in object oriented databases corresponds to virtual schemawith restructured generalization and decomposition hierarchies. Numbers of viewcreation methodologies have been proposed. A major drawback of existing m... A view in object oriented databases corresponds to virtual schemawith restructured generalization and decomposition hierarchies. Numbers of viewcreation methodologies have been proposed. A major drawback of existing method-ologies is that they do not maintain the closure property. That is, the result of aquery does not have the same semantics as embodied in the object oriented datamodel. Therefore, this paper presents a view creation methodology that derives aclass in response to a user's query, integrates derived class in global schema (i.e.,considers the problem of classes moving in class hierarchy) and selects the requiredclasses from global schema to create the view for user's query. Novel idea of viewcreation includes: (a) an object algebra for class derivation and customization (wherethe derived classes in terms of object instances and procedure/methods are studied),(b) maintenance of closure property, and (c) classification algorithm which providesmechanism to deal with the problem of a class moving in a class hierarchy. 展开更多
关键词 object manipulation type level operation instance level operation object algebra object operator operator syntax operator semantics derived class class integration view creation algorithm
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非紧距离空间上的Lipschitz-α算子代数 被引量:4
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作者 陈广锋 曹怀信 《广西师范大学学报(自然科学版)》 CAS 北大核心 2006年第3期34-37,共4页
讨论了由非紧距离空间(X,d)到一般B anach代数A中的各种L ipsch itz-α算子代数,证明了它们分别关于某些范数构成B anach代数,并讨论了各种B anach代数之间的关系。
关键词 非紧距离空间 Lipschitz-α算子 BANACH代数
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算子李代数g(G,M)[σ]的子代数 被引量:3
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作者 李立 王辉 马丽丽 《数学的实践与认识》 CSCD 北大核心 2013年第17期233-236,共4页
在李代数的研究中,经常使用算子李代数的结构去刻划其它李代数的代数结构,由算子构成的李代数在李代数理论中占有重要的位置.构造了算子李代数g(G,M)[σ]的子代数,然后讨论了这些子代数的代数结构.
关键词 顶点算子 李代数 子代数 代数结构
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The Mathematical Foundations of General Relativity Revisited 被引量:2
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作者 Jean-Francois Pommaret 《Journal of Modern Physics》 2013年第8期223-239,共17页
The purpose of this paper is to present for the first time an elementary summary of a few recent results obtained through the application of the formal theory of partial differential equations and Lie pseudogroups in ... The purpose of this paper is to present for the first time an elementary summary of a few recent results obtained through the application of the formal theory of partial differential equations and Lie pseudogroups in order to revisit the mathematical foundations of general relativity. Other engineering examples (control theory, elasticity theory, electromagnetism) will also be considered in order to illustrate the three fundamental results that we shall provide successively. 1) VESSIOT VERSUS CARTAN: The quadratic terms appearing in the “Riemann tensor” according to the “Vessiot structure equations” must not be identified with the quadratic terms appearing in the well known “Cartan structure equations” for Lie groups. In particular, “curvature + torsion” (Cartan) must not be considered as a generalization of “curvature alone” (Vessiot). 2) JANET VERSUS SPENCER: The “Ricci tensor” only depends on the nonlinear transformations (called “elations” by Cartan in 1922) that describe the “difference” existing between the Weyl group (10 parameters of the Poincaré subgroup + 1 dilatation) and the conformal group of space-time (15 parameters). It can be defined without using the indices leading to the standard contraction or trace of the Riemann tensor. Meanwhile, we shall obtain the number of components of the Riemann and Weyl tensors without any combinatoric argument on the exchange of indices. Accordingly and contrary to the “Janet sequence”, the “Spencer sequence” for the conformal Killing system and its formal adjoint fully describe the Cosserat equations, Maxwell equations and Weyl equations but General Relativity is not coherent with this result. 3) ALGEBRA VERSUS GEOMETRY: Using the powerful methods of “Algebraic Analysis”, that is a mixture of homological agebra and differential geometry, we shall prove that, contrary to other equations of physics (Cauchy equations, Cosserat equations, Maxwell equations), the Einstein equations cannot be “parametrized”, that is the g 展开更多
关键词 General Relativity Riemann TENSOR Weyl TENSOR Ricci TENSOR Einstein Equations LIE Groups LIE Pseudogroups DIFFERENTIAL SEQUENCE SPENCER operator JANET SEQUENCE SPENCER SEQUENCE DIFFERENTIAL Module Homological algebra Extension Modules Split Exact SEQUENCE
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