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Extended Group of the Subgroup Gr in Linear Group Over the Principal Ideal Ring 被引量:1
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作者 WEI Zong-li QU He-mei 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期600-605,共6页
Suppose R is a principal ideal ring, R^* is a multiplicative group which is composed of all reversible elements in R, and Mn(R), GL(n,R), SL(n,R) are denoted by,Mn(R)={A=(aij)n×n|aij∈R,i,j=1,2…,n},G... Suppose R is a principal ideal ring, R^* is a multiplicative group which is composed of all reversible elements in R, and Mn(R), GL(n,R), SL(n,R) are denoted by,Mn(R)={A=(aij)n×n|aij∈R,i,j=1,2…,n},GL(n,R)={g|g∈Mn(R),det g∈R^*},SL(n,R)={g∈GL(n,R)|det g=1},SL(n,R)≤G≤GL(n,R)(n≥3),respectively,then basing on these facts, this paper mainly focus on discussing all extended groups of Gr={(O D^A B)∈G|A∈GL(r,R),(1≤r〈n)}in G when R is a principal ideal ring. 展开更多
关键词 principal ideal ring extended group linear group
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The Transfer Ideal under the Action of a Nonmetacyclic Group in the Modular Case
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作者 JIA PAN-PAN NAN JI-ZHU 《Communications in Mathematical Research》 CSCD 2019年第3期273-282,共10页
Let Fq be a finite field of characteristic p (p ≠2) and V4 a four-dimensional Fq-vector space. In this paper, we mainly determine the structure of the transfer ideal for the ring of polynomials Fq[V4] under the actio... Let Fq be a finite field of characteristic p (p ≠2) and V4 a four-dimensional Fq-vector space. In this paper, we mainly determine the structure of the transfer ideal for the ring of polynomials Fq[V4] under the action of a nonmetacyclic p-group P in the modular case. We prove that the height of the transfer ideal is 1 using the fixed point sets of the elements of order p in P and that the transfer ideal is a principal ideal. 展开更多
关键词 INVARIANT P-group coinvariant TRANSFER ideal principal ideal
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Wind turbine clutter mitigation using morphological component analysis with group sparsity
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作者 WAN Xiaoyu SHEN Mingwei +1 位作者 WU Di ZHU Daiyin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期714-722,共9页
To address the problem that dynamic wind turbine clutter(WTC)significantly degrades the performance of weather radar,a WTC mitigation algorithm using morphological component analysis(MCA)with group sparsity is studied... To address the problem that dynamic wind turbine clutter(WTC)significantly degrades the performance of weather radar,a WTC mitigation algorithm using morphological component analysis(MCA)with group sparsity is studied in this paper.The ground clutter is suppressed firstly to reduce the morphological compositions of radar echo.After that,the MCA algorithm is applied and the window used in the short-time Fourier transform(STFT)is optimized to lessen the spectrum leakage of WTC.Finally,the group sparsity structure of WTC in the STFT domain can be utilized to decrease the degrees of freedom in the solution,thus contributing to better estimation performance of weather signals.The effectiveness and feasibility of the proposed method are demonstrated by numerical simulations. 展开更多
关键词 weather radar wind turbine clutter(WTC) morphological component analysis(MCA) short-time Fourier transform(STFT) group sparsity
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Lie point symmetry algebras and finite transformation groups of the general Broer-Kaup system 被引量:1
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作者 贾曼 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第6期1534-1544,共11页
Using a new symmetry group theory, the transformation groups and symmetries of the general Broer-Kaup system are obtained. The results are much simpler than those obtained via the standard approaches.
关键词 Lie point symmetry finite transformation group new symmetry group theory
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On the Structure of the Augmentation Quotient Group for Some Non-abelian p-groups
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作者 ZHAO HUI-FANG NAN JI-ZHU Du Xian-kun 《Communications in Mathematical Research》 CSCD 2017年第4期289-303,共15页
In this paper, we study the basis of augmentation ideals and the quotient groups of finite non-abelian p-group which has a cyclic subgroup of index p, where p is an odd prime, and k is greater than or equal to 3. A co... In this paper, we study the basis of augmentation ideals and the quotient groups of finite non-abelian p-group which has a cyclic subgroup of index p, where p is an odd prime, and k is greater than or equal to 3. A concrete basis for the augmentation ideal is obtained and then the structure of its quotient groups can be determined. 展开更多
关键词 integral group ring augmentation ideal quotient group P-group
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Hardy Type Estimates for Riesz Transforms Associated with Schrdinger Operators on the Heisenberg Group
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作者 Yu Liu Guobin Tang 《Analysis in Theory and Applications》 CSCD 2016年第1期78-89,共12页
Abstract. Let H^n be the Heisenberg group and Q = 2n+2 be its homogeneous dimen- sion. In this paper, we consider the Schr6dinger operator -△H^n +V, where △H^n is the sub-Laplacian and V is the nonnegative potenti... Abstract. Let H^n be the Heisenberg group and Q = 2n+2 be its homogeneous dimen- sion. In this paper, we consider the Schr6dinger operator -△H^n +V, where △H^n is the sub-Laplacian and V is the nonnegative potential belonging to the reverse H61der class Bql for ql _〉 Q/2. We show that the operators T1 = V(-△H^n-In +V)-1 and T2 = V1/2(-△H^n-V)-1/2 are both bounded from 1 n HL^1(H^n ) into L1(H^n). Our results are also valid on the stratified Lie group. 展开更多
关键词 Heisenberg group stratified Lie group reverse H61der class Riesz transform Schr6dinger operator.
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L^p BOUNDEDNESS OF COMMUTATOR OPERATOR ASSOCIATED WITH SCHRDINGER OPERATORS ON HEISENBERG GROUP 被引量:3
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作者 李澎涛 彭立中 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期568-578,共11页
Let L = -△Hn + V be a SchrSdinger operator on Heisenberg group Hn, where AHn is the sublaplacian and the nonnegative potential V belongs to the reverse HSlder class BQ/2 where Q is the homogeneous dimension of Hn. L... Let L = -△Hn + V be a SchrSdinger operator on Heisenberg group Hn, where AHn is the sublaplacian and the nonnegative potential V belongs to the reverse HSlder class BQ/2 where Q is the homogeneous dimension of Hn. Let T1 = (--△Hn +V)-1V, T2 = (-△Hn +V)-1/2V1/2, and T3 = (--AHn +V)-I/2△Hn, then we verify that [b, Ti], i = 1, 2, 3 are bounded on some LP(Hn), where b ∈ BMO(Hn). Note that the kernel of Ti, i = 1, 2, 3 has no smoothness. 展开更多
关键词 COMMUTATOR BMO Heisenberg group BOUNDEDNESS Riesz transforms as-sociated to SchrSdinger operators
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Lie symmetry group transformation for MHD natural convection flow of nanofluid over linearly porous stretching sheet in presence of thermal stratification 被引量:2
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作者 A.B.ROSMILA R.KANDASAMY I.MUHAIMIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期593-604,共12页
The magnetohydrodynamics (MHD) convection flow and heat transfer of an incompressible viscous nanofluid past a semi-infinite vertical stretching sheet in the pres- ence of thermal stratification are examined. The pa... The magnetohydrodynamics (MHD) convection flow and heat transfer of an incompressible viscous nanofluid past a semi-infinite vertical stretching sheet in the pres- ence of thermal stratification are examined. The partial differential equations governing the problem under consideration are transformed by a special form of the Lie symmetry group transformations, i.e., a one-parameter group of transformations into a system of ordinary differential equations which are numerically solved using the Runge-Kutta-Gill- based shooting method. It is concluded that the flow field, temperature, and nanoparticle volume fraction profiles are significantly influenced by the thermal stratification and the magnetic field. 展开更多
关键词 Lie symmetry group transformation NANOFLUID porous medium thermalstratification magnetic field
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THE UNIFORMLY BOUNDEDNESS OF THE RIESZ TRANSFORMS ON THE CAYLEY HEISENBERG GROUPS 被引量:2
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作者 栾静闻 朱赋鎏 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期895-914,共20页
In this article,the authors estimate some functions by using the explicit expression of the heat kernels for the Cayley Heisenberg groups,and then prove the uniform boundedness of the Riesz transforms on these nilpote... In this article,the authors estimate some functions by using the explicit expression of the heat kernels for the Cayley Heisenberg groups,and then prove the uniform boundedness of the Riesz transforms on these nilpotent Lie groups. 展开更多
关键词 Cayley Heisenberg group heat kernel Riesz transform
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On fundamental solution for powers of the sub-Laplacian on the Heisenberg group 被引量:1
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作者 WANG Hai-meng WU Qing-yan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第3期365-378,共14页
We discuss the fundamental solution for m-th powers of the sub-Laplacian on the Heisenberg group. We use the representation theory of the Heisenberg group to analyze the associated m-th powers of the sub-Laplacian and... We discuss the fundamental solution for m-th powers of the sub-Laplacian on the Heisenberg group. We use the representation theory of the Heisenberg group to analyze the associated m-th powers of the sub-Laplacian and to construct its fundamental solution. Besides, the series representation of the fundamental solution for square of the sub-Laplacian on the Heisenberg group is given and we also get the closed form of the fundamental solution for square of the sub-Laplacian on the Heisenberg group with dimension n = 2, 3, 4. 展开更多
关键词 SUB-LAPLACIAN fundamental solution group Fourier transform Plancherel formula Heisenberg group
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Lie Groups Actions on Non Orientable <i>n</i>-Dimensional Complex Manifolds 被引量:3
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作者 T. Cao-Huu D. Ghisa 《Advances in Pure Mathematics》 2021年第6期604-610,共7页
Analytic atlases on <img src="Edit_948e45b7-cbef-425e-bb79-28648b859994.png" width="23" height="22" alt="" /> can be easily defined making it an <em>n</em>-dim... Analytic atlases on <img src="Edit_948e45b7-cbef-425e-bb79-28648b859994.png" width="23" height="22" alt="" /> can be easily defined making it an <em>n</em>-dimensional complex manifold. Then with the help of bi-M<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#246;</span></span>bius transformations in complex coordinates Abelian groups are constructed making this manifold a Lie group. Actions of Lie groups on differentiable manifolds are well known and serve different purposes. We have introduced in previous works actions of Lie groups on non orientable Klein surfaces. The purpose of this work is to extend those studies to non orientable <em>n</em>-dimensional complex manifolds. Such manifolds are obtained by factorizing <img src="Edit_7e5721ee-bb7f-4224-bd52-7d4641ac1c73.png" width="23" height="22" alt="" /> with the two elements group of a fixed point free antianalytic involution of <img src="Edit_ddfdac64-b296-48c5-9bb2-932eb3d76008.png" width="23" height="22" alt="" />. Involutions <strong>h(z)</strong> of this kind are obtained linearly by composing special M<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#246;</span></span>bius transformations of the planes with the mapping <img src="Edit_4cda269a-9399-41ae-a5da-0c9d18a419ab.png" width="89" height="24" alt="" /><img src="Edit_4cda269a-9399-41ae-a5da-0c9d18a419ab.png" width="85" height="22" alt="" />. A convenient partition of <img src="Edit_9e899708-41b0-4351-a12b-cc6efb5b1581.png" width="23" height="22" alt="" /> is performed which helps defining an internal operation on <img src="Edit_7cd42987-68f8-4e4c-9382-cbc68b56377e.png" width="49" height="26" alt="" /> and finally actions of the previously defined Lie groups on the non orientable manifold <img src="Edit_5740b48c-f9ea-438d-a87d-8cdc1f83662b.png" width="49" height="25" alt="" /> are displayed. 展开更多
关键词 Analytic Atlas Complex Manifold Möbius Transformation Lie group Action
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ALMOST PERIODICITY AND EQUICONTINUITY OF THE TOPOLOGICAL TRANSFORMATION GROUP 被引量:1
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作者 Li Zhicong Li Juntao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期467-472,共6页
In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transf... In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transformation group is topologically equivalent to an isometric one if it is uniformly equicontinuous. 展开更多
关键词 uniform space topological transformation group EQUICONTINUITY almost periodicity compactly almost periodicity.
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A kind of signature scheme based on class groups of quadratic fields 被引量:1
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作者 董晓蕾 曹珍富 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第6期583-587,共5页
Quadratic-field cryptosystem is a cryptosystem built from discrete logarithm problem in ideal class groups of quadratic fields(CL-DLP). The problem on digital signature scheme based on ideal class groups of quadratic ... Quadratic-field cryptosystem is a cryptosystem built from discrete logarithm problem in ideal class groups of quadratic fields(CL-DLP). The problem on digital signature scheme based on ideal class groups of quadratic fields remained open, because of the difficulty of computing class numbers of quadratic fields. In this paper, according to our researches on quadratic fields, we construct the first digital signature scheme in ideal class groups of quadratic fields, using q as modulus, which denotes the prime divisors of ideal class numbers of quadratic fields. Security of the new signature scheme is based fully on CL-DLP. This paper also investigates realization of the scheme, and proposes the concrete technique. In addition, the technique introduced in the paper can be utilized to realize signature schemes of other kinds. 展开更多
关键词 quadratic-field cryptosystem digital signature ideal class groups discrete logarithm problem
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Preliminary group classification of quasilinear third-order evolution equations
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作者 黄定江 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期275-292,共18页
Group classification of quasilinear third-order evolution equations is given by using the classical infinitesimal Lie method, the technique of equivalence transformations, and the theory of classification of abstract ... Group classification of quasilinear third-order evolution equations is given by using the classical infinitesimal Lie method, the technique of equivalence transformations, and the theory of classification of abstract low-dimensional Lie algebras. We show that there are three equations admitting simple Lie algebras of dimension three. All non-equivalent equations admitting simple Lie algebras are nothing but these three. Furthermore, we also show that there exist two, five, twenty-nine and twenty-six non- equivalent third-order nonlinear evolution equations admitting one-, two-, three-, and four-dimensional solvable Lie algebras, respectively. 展开更多
关键词 quasilinear third-order evolution equations group classification classical infinitesimal Lie method equivalence transformation group abstract Lie algebras
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Symmetry groups and Gauss kernels of Schrdinger equations
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作者 Kang Jing Qu Chang-Zheng 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期66-75,共10页
The relationship between symmetries and Gauss kernels for the SchrSdinger equation iut = uxx + f(x)u is established. It is shown that if the Lie point symmetries of the equation are nontrivial, a classical integral... The relationship between symmetries and Gauss kernels for the SchrSdinger equation iut = uxx + f(x)u is established. It is shown that if the Lie point symmetries of the equation are nontrivial, a classical integral transformations of the Gauss kernels can be obtained. Then the Gauss kernels of Schroedinger equations are derived by inverting the integral transformations. Furthermore, the relationship between Gauss kernels for two equations related by an equivalence transformation is identified. 展开更多
关键词 Schroedinger equation symmetry group Gauss kernel equivalence transformation
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HOLOMORPHIC HARMONIC ANALYSIS ON COMPLEX REDUCTIVE GROUPS
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作者 安金鹏 钱敏 王正栋 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期560-572,共13页
The authors define the holomorphic Fourier transform of holomorphic functions on complex reductive groups, prove some properties such as the Fourier inversion formula, and give some applications. The definition of the... The authors define the holomorphic Fourier transform of holomorphic functions on complex reductive groups, prove some properties such as the Fourier inversion formula, and give some applications. The definition of the holomorphic Fourier transform makes use of the notion of K-admissible measures. The authors prove that K-admissible measures are abundant, and the definition of holomorphic Fourier transform is independent of the choice of K-admissible measures. 展开更多
关键词 Complex reductive group Fourier transform holomorphic representation
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Finite symmetry transformation group and localized structures of the (2+1)-dimensional coupled Burgers equation
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作者 雷娅 杨铎 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期46-49,共4页
In this paper, the finite symmetry transformation group of the (2+1)-dimensional coupled Burgers equation is studied by the modified direct method, and with the help of the truncated Painleve′ expansion approach, ... In this paper, the finite symmetry transformation group of the (2+1)-dimensional coupled Burgers equation is studied by the modified direct method, and with the help of the truncated Painleve′ expansion approach, some special localized structures for the (2+1)-dimensional coupled Burgers equation are obtained, in particular, the dromion-like and solitoff-like structures. 展开更多
关键词 finite transformation group modified direct method truncated Painleve′ expansion approach localized structure
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ADMISSIBLE WAVELETS ON THE PRODUCT HEISENBERG GROUP H_n
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作者 何建勋 彭立中 《Acta Mathematica Scientia》 SCIE CSCD 1998年第S1期58-67,共10页
Let H. be the n-direct proded of Heisenbery group H, P the affine group of Hn. Then P ho a natural unitary representation U on L2(Hn). In this paper,the direct sum decomposition of irreducible invariant closed subspac... Let H. be the n-direct proded of Heisenbery group H, P the affine group of Hn. Then P ho a natural unitary representation U on L2(Hn). In this paper,the direct sum decomposition of irreducible invariant closed subspaces under unitary representation U for L2(Hn) is given. The restrictins of U on these subspaces are square-integrable. The charactedsation of admissible condition is obtained in ierms of the Fourier transform. By seleting appropriately an orthogonal wavelet basis and the wavelet transform,the authors obtain the orthogonal direct chin decomposinon of function space L2(P,dμl). 展开更多
关键词 Admissible condition Wavelet transform Heisenbery group Orthogonal dir4ect sum decomposition Generalized upper half-plance
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Classical Fourier Analysis over Homogeneous Spaces of Compact Groups
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作者 Arash Ghaani Farashahi 《Analysis in Theory and Applications》 CSCD 2016年第4期339-354,共16页
This paper introduces a unified operator theory approach to the abstract Fourier analysis over homogeneous spaces of compact groups. Let G be a compact group and H be a closed subgroup of G. Let G/H be the left coset ... This paper introduces a unified operator theory approach to the abstract Fourier analysis over homogeneous spaces of compact groups. Let G be a compact group and H be a closed subgroup of G. Let G/H be the left coset space of H in G and μ be the normalized G-invariant measure on G/H associated to the Weil's formula. Then, we present a generalized abstract framework of Fourier analysis for the Hilbert function space L^2 (G / H, μ). 展开更多
关键词 Compact group homogeneous space dual space Fourier transform Plancherel(trace) formula Peter-Weyl Theorem
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On the Group of Units for the Ring of Linear Transformations
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作者 张光辉 孙应德 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第4期355-359,共5页
In this paper, we introduce a practical method for obtaining the structure of thegroup of units for the ring of linear transformations of a vector space over an arbitrary field,and we give a further generalization of ... In this paper, we introduce a practical method for obtaining the structure of thegroup of units for the ring of linear transformations of a vector space over an arbitrary field,and we give a further generalization of the result in [3]. 展开更多
关键词 semidirect product linear transformation normal group BASIS
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