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On the Approximation Problem of Quasi Hermite-Fejér Type Rational Interpolation 被引量:1
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作者 王子玉 田继善 《Chinese Quarterly Journal of Mathematics》 CSCD 1990年第1期157-161,共5页
This paper has researched two operators of quasi Hermite-Fejér type rational interpolation.Rather exact pointwise estimate is geven,The rasu- Its of [1] are improved.
关键词 拟Hiщte-Fejér型有理插值算子 点态估计 连续模 子线性算子 逼近问题
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Influence of the Electric Field on the Properties of the Bound Magnetopolaron in GaAs Semiconductor Quantum Wells 被引量:3
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作者 单淑萍 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期438-441,共4页
The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformati... The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformation method. The relationships between the polaron's ground state energy and the Coulomb bound potential, electric field, magnetic field, and well-width are derived and discussed. Our numerical results show that the absolute value of the polaron's ground state energy increases as the electric field and the Coulomb bound potential increase, and decreases as the well-width and the magnetic field strength increase. When the well-width is small,the quantum size effect is significant. 展开更多
关键词 quantum well bound magnetopolaron linear combination operator ground state energy
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The Multiplier Algebra of a Ternary Algebra 被引量:1
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作者 许天周 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期6-11,共6页
In this article, we have given the definition of the relative double multiplier (quasi-multiplier) on a ternary algebra,and studied the isomorphic problem of the multiplier algebra M(A,e) of a ternary algerbra A.
关键词 multiplier algebra ternary algebra relative arens product
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IMPROVEMENT OF MATRIX REPRESENTATION METHOD IN NORMAL FORM THEORY 被引量:1
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作者 韩景龙 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期166-171,共6页
In this paper, based on the invariant subspace theory and adjoint operator concept of linear operator, a new matrix representation method is proposed to calculate the normal forms of n order general nonlinear dyna... In this paper, based on the invariant subspace theory and adjoint operator concept of linear operator, a new matrix representation method is proposed to calculate the normal forms of n order general nonlinear dynamic systems. In the method, there is no need to determine the structure of the class of normal forms in advance. Because the subspace is not related to the dimensions of the system and the order of the normal forms directly, it is determined only by a given vector field. So the normal forms with high orders and dimensions can be calculated by the method without difficulties. In this paper, is used the method for selecting the minimal subspace and solving homological equations in the subspace, the examples show that the method is very effective. 展开更多
关键词 dynamic system normal forms NONLINEARITY linear space adjoint operator
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Higher-Dimensional KdV Equations and Their Soliton Solutions 被引量:12
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作者 ZHANG Yu-Feng Tam Honwah ZHAO Jing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期411-413,共3页
A (2+1)-dimensional KdV equation is obtained by use of Hirota method, which possesses N-soliton solution, specially its exact two-soliton solution is presented. By employing a proper algebraic transformation and th... A (2+1)-dimensional KdV equation is obtained by use of Hirota method, which possesses N-soliton solution, specially its exact two-soliton solution is presented. By employing a proper algebraic transformation and the Riccati equation, a type of hell-shape soliton solutions are produced via regarding the variable in the Riccati equation as the independent variable. Finally, we extend the above (2+1)-dimensional KdV equation into (3+1)-dimensional equation, the two-soliton solutions are given. 展开更多
关键词 bilinear operator KdV equation soliton equation
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Effects of Thermal Lattice Vibration on the Effective Potential of Weak-Coupling Bipolaron in a Quantum Dot 被引量:2
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作者 Eerdunchaolu Wuyunqimuge +2 位作者 XIAO Xin HAN Chao XIN Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第1期157-160,共4页
Based on the Huybrechts' linear-combination operator,effects of thermal lattice vibration on the effective potential of weak-coupling bipolaron in semiconductor quantum dots are studied by using the LLP variationa... Based on the Huybrechts' linear-combination operator,effects of thermal lattice vibration on the effective potential of weak-coupling bipolaron in semiconductor quantum dots are studied by using the LLP variational method and quantum statistical theory.The results show that the absolute value of the induced potential of the bipolaron increases with increasing the electron-phonon coupling strength,but decreases with increasing the temperature and the distance of electrons,respectively;the absolute value of the effective potential increases with increasing the radius of the quantum dot,electron-phonon coupling strength and the distance of electrons,respectively,but decreases with increasing the temperature;the temperature and electron-phonon interaction have the important influence on the formation and state properties of the bipolaron:the bipolarons in the bound state are closer and more stable when the electron-phonon coupling strength is larger or the temperature is lower;the confinement potential and coulomb repulsive potential between electrons are unfavorable to the formation of bipolarons in the bound state. 展开更多
关键词 quantum dot BIPOLARON induced potential effective potential thermal lattice vibration polaroneffects
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On the Representation of Some Subnormal Operators
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作者 席俊 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期36-40,共5页
Let T be pure subnormal operator. In this paper necessary and sufficiert conditions that T=N+K are given,where N is normal, K is quasinormal and NK=KN.
关键词 subnormal operators self-dual subnormal operators
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Boundedness of Operators in Morrey Spaces over Vilenkin Groups 被引量:2
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作者 WANGYue-shan ZHUXiu-ge 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期315-319,共5页
Let G be a locally compact Vilenkin gro up . We will establish the boundedness in Morrey spaces L p,λ (G) for a la rge class of sublinear operators and linear commutators.
关键词 Vilenkin group Morrey space sublinear operator com mutator BMO
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Entanglement Capacity of Two-Qubit Unitary Operator with the Help of Auxiliary System 被引量:2
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作者 HU Bao-Lin DI Yao-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1029-1032,共4页
The'entanglement capacity of general two-qubit unitary operators is studied when auxiliary systems are allowed, and the analytical results based on linear entropy when input states are disentangled are given. From th... The'entanglement capacity of general two-qubit unitary operators is studied when auxiliary systems are allowed, and the analytical results based on linear entropy when input states are disentangled are given. From the results the condition for perfect entangler, α1 = α2 = π/4, is obtained. Contrary to the case without auxiliary system, the parameter α3 may play active role to the entanglement capacity when auxiliary systems are allowed. 展开更多
关键词 unitary operator entanglement capacity linear entropy auxiliary system
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Operator Matrix Forms of Positive Operators 被引量:4
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作者 杜鸿科 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第4期9-12,共4页
If a 3-tuple (A:H_1→H_1,B:H_2→H_1,C:H_2→H_2) of operators on Hilbert spaces is given,we proved that the operator A:= on H=H_1⊕H_2 is≥0 if and only if A≥0,R(B) R(A1/2)and C≥B~* A^+ B, where A^+ is the generalize... If a 3-tuple (A:H_1→H_1,B:H_2→H_1,C:H_2→H_2) of operators on Hilbert spaces is given,we proved that the operator A:= on H=H_1⊕H_2 is≥0 if and only if A≥0,R(B) R(A1/2)and C≥B~* A^+ B, where A^+ is the generalized inverse of A. In general,A^+ is a closed operator,but since R(B) R(A1/2),B~* A^+ B is bounded yet. 展开更多
关键词 positive operator range of operator
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On Approximation of Nonbounded Continuous Functions
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作者 ZHENGCheng-de WANGRen-hong 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第1期44-48,共5页
This paper generalizes the basic principle of multiplier-enlargement approach to approximating any nonbounded continuous functions with positive linear operators, and as an example, Bernstein polynomial operators are ... This paper generalizes the basic principle of multiplier-enlargement approach to approximating any nonbounded continuous functions with positive linear operators, and as an example, Bernstein polynomial operators are analysed and studied. This paper gives a certain theorem as a general rule to approximate any nonbounded continuous functions. 展开更多
关键词 positive linear operator approximation of nonbounded continuous function method of multiplier-enlargement Bernstein polynomial operator
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Herz Spaces on Nilpotent Lie Groups and Its Applications
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作者 ZHUYue-ping LIDeng-feng 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第1期74-81,共8页
In this paper, we define Herz type spaces on nilpotent Lie groups and give the boundedess of heat kernel and Riesz transform on Herz spaces.
关键词 nilpotent Lie groups Herz spaces heat kernel
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Regularity of Continuous Linear Operators on Banach Function Spaces
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作者 JIANGNian-shengt ChenZi-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期51-56,共6页
In this paper we present some characterizations of Banach function spaces on which every continuous linear operator is regular.
关键词 Banach function space continuous linear operator REGULAR
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Generalized Szász-Mirakjan Operator Approximation
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作者 程海来 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第3期24-29,共6页
In this paper we shall defin a kind of generahzed Szász-Mirakjan operator and discuss its convergence and degree of approximation,extend some results got by J.Grof and Z.Ditzian.
关键词 degree of approximation positive operator uniform convergence pointwise convergence
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On Dual Cosine Operator Function
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作者 丁天彪 田利钦 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第3期87-90,共4页
Some basic properties of daul cosine operator function are given. The concept and characterization of θ-reflexivity with respect to cosine operator function are first studied.
关键词 cosine operator function DUALITY θ-reflexivity
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Ab Initio Study on Structural and Magnetic Properties of Ni-Pd and Ni-Pt Linear and Zigzag Nanowires
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作者 CHE Xing-Lai LI Jia-Hao DAI Ye LIU Bai-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期123-127,共5页
Employing the accurate frozen-core full-potential projector augmented-wave method,the self-consistentelectronic structure calculations were carried out on pure Ni,Pd,Pt and mixed Ni-Pd and Ni-Pt free-standing linear a... Employing the accurate frozen-core full-potential projector augmented-wave method,the self-consistentelectronic structure calculations were carried out on pure Ni,Pd,Pt and mixed Ni-Pd and Ni-Pt free-standing linear andzigzag nanowires.The bond lengths for all these systems are generally increased as their structures change from the linearto the zigzag chain.The bond lengths for Ni-Pd and Ni-Pt wires are in between the values of corresponding pure systemand the bond angles around 60° suggesting the possible formation of Ni-Pd and Ni-Pt bimetallic materials.In mixedNi-Pd and Ni-Pt chains,the Ni,Pd,and Pt atoms have quite high local magnetic moments.The calculations suggestthat the magnetic moments in linear nanowires are generally larger than the ones of corresponding zigzag nanowires.Itis found that there is hybridization between Ni 3d and Pd 4d,Ni 3d and Pt 5d states,which may significantly affectstructural stability and magnetism of Ni-Pd and Ni-Pt nanowires. 展开更多
关键词 Ab initio study MAGNETISM NANOWIRES
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Bilocal Derivations of Reflexive Algebras
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作者 荆武 王晓静 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第2期197-202,共6页
Let A be a reflexive algebra in reflexive Banach space X such that both O+ ≠O and X_ ≠ X in LatA, then the set of all derivations of A into B(X) is topologically algebraically bireflexive.
关键词 reflexive algebra DERIVATION bifocal derivation.
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Local Hardy spaces of Musielak-Orlicz type and their applications 被引量:14
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作者 YANG DaChun YANG SiBei 《Science China Mathematics》 SCIE 2012年第8期1677-1720,共44页
Let¢ : Nn x [0,∞) -4 [0, ∞) be a function such that ¢(x,.) is an Orlicz function and ¢(.,t) ∈ Aloc∞(Nn) (the class of local weights introduced by Rychkov). In this paper, the authors introduce a loca... Let¢ : Nn x [0,∞) -4 [0, ∞) be a function such that ¢(x,.) is an Orlicz function and ¢(.,t) ∈ Aloc∞(Nn) (the class of local weights introduced by Rychkov). In this paper, the authors introduce a local Musielak-Orlicz Hardy space h¢(Nn) by the local grand maximal function, and a local BMO-type space bmo¢(Nn) which is further proved to be the dual space of h¢(Nn). As an application, the authors prove that the class of pointwise multipliers for the local BMO-type space bmo¢(Nn), characterized by Nakai and Yabuta, is just the dual of LI(Rn) + hФ0 (Rn), where Ф is an increasing function on (0, co) satisfying some additional growth conditions and Ф0 a Musielak-Orlicz function induced by Ф. Characterizations of h¢(Rn), including the atoms, the local vertical and the local nontangential maximal functions, are presented. Using the atomic char- acterization, the authors prove the existence of finite atomic decompositions achieving the norm in some dense subspaces of h¢(Rn), from which, the authors further deduce some criterions for the boundedness on h¢(Rn) of some sublinear operators. Finally, the authors show that the local Riesz transforms and some pseudo-differential operators are bounded on h¢(Rn). 展开更多
关键词 local weigkt Musielak-Orlicz function local Hardy space ATOM local maximal function localBMO space dual space pointwise multiplier local Riesz transform pseudo-differential operator
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CPT-Frames for Non-Hermitian Hamiltonians 被引量:2
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作者 曹怀信 郭志华 陈峥立 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第9期328-334,共7页
Based on the PT-symmetric quantum theory, the concepts of PT-frame, PT-symmetric operator and CPT-frame on a Hilbert space K and for an operator on K are proposed. It is proved that the spectrum and point spectrum of ... Based on the PT-symmetric quantum theory, the concepts of PT-frame, PT-symmetric operator and CPT-frame on a Hilbert space K and for an operator on K are proposed. It is proved that the spectrum and point spectrum of a PT-symmetric linear operator are both symmetric with respect to the real axis and the eigenvalues of an unbroken PT-symmetric operator are real. For a linear operator H on Cd, it is proved that H has unbroken PT- symmetry if and only if it has d different eigenvalues and the corresponding eigenstates are eigenstates of PT. Given a CPT-frame on K, a new positive inner product on K is induced and called CPT-inner product. Te relationship between the CPT-adjoint and the Dirac adjoint of a densely defined linear operator is derived, and it is proved that an operator which has a bounded CPT-frame is CPT-Hermitian if and only if it is T-symmetric, in that case, it is similar to a Hermitian operator. The existence of an operator C consisting of a CPT-frame is discussed, These concepts and results will serve a mathematical discussion about PT-symmetric quantum mechanics. 展开更多
关键词 CPT-frame PT-frame PT-SYMMETRY OPERATOR
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METRIC GENERALIZED INVERSE OF LINEAR OPERATOR IN BANACH SPACE 被引量:29
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作者 WANGHUI WANGYUWEN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2003年第4期509-520,共12页
The Moore-Penrose metric generalized inverse T+ of linear operator T in Banach space is systematically investigated in this paper. Unlike the case in Hilbert space, even T is a linear operator in Banach Space, the Moo... The Moore-Penrose metric generalized inverse T+ of linear operator T in Banach space is systematically investigated in this paper. Unlike the case in Hilbert space, even T is a linear operator in Banach Space, the Moore-Penrose metric generalized inverse T+ is usually homogeneous and nonlinear in general. By means of the methods of geometry of Banach Space, the necessary and sufficient conditions for existence, continuitv, linearity and minimum property of the Moore-Penrose metric generalized inverse T+ will be given, and some properties of T+ will be investigated in this paper. 展开更多
关键词 Banach space Metric generalized inverse Generalized orthogonal decomposition Homogeneous operator
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