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NEW STRUCTURES FOR NON-SELFSIMILAR SOLUTIONS OF MULTI-DIMENSIONAL CONSERVATION LAWS 被引量:4
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作者 杨小舟 魏涛 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1182-1202,共21页
In this article, we get non-selfsimilar elementary waves of the conservation laws in another kind of view, which is different from the usual self-similar transformation. The solution has different global structure. Th... In this article, we get non-selfsimilar elementary waves of the conservation laws in another kind of view, which is different from the usual self-similar transformation. The solution has different global structure. This article is divided into three parts. The first part is introduction. In the second part, we discuss non-selfsimilar elementary waves and their interactions of a class of twodimensional conservation laws. In this case, we consider the case that the initial discontinuity is parabola with u+ 〉 0, while explicit non-selfsirnilar rarefaction wave can be obtained. In the second part, we consider the solution structure of case u+ 〈 0. The new solution structures are obtained by the interactions between different elementary waves, and will continue to interact with other states. Global solutions would be very different from the situation of one dimension. 展开更多
关键词 non-selfsimilar shock wave rarefaction wave ENVELOPE multi-dimensional conservation laws
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A CLASS OF MULTIWAVELETS AND PROJECTED FRAMES FROM TWO-DIRECTION WAVELETS 被引量:3
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作者 李尤发 杨守志 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期285-300,共16页
This article aims at studying two-direction refinable functions and two-direction wavelets in the setting R^s, s 〉 1. We give a sufficient condition for a two-direction refinable function belonging to L^2(R^s). The... This article aims at studying two-direction refinable functions and two-direction wavelets in the setting R^s, s 〉 1. We give a sufficient condition for a two-direction refinable function belonging to L^2(R^s). Then, two theorems are given for constructing biorthogonal (orthogonal) two-direction refinable functions in L^2(R^s) and their biorthogonal (orthogonal) two-direction wavelets, respectively. From the constructed biorthogonal (orthogonal) two-direction wavelets, symmetric biorthogonal (orthogonal) multiwaveles in L^2(R^s) can be obtained easily. Applying the projection method to biorthogonal (orthogonal) two-direction wavelets in L^2(R^s), we can get dual (tight) two-direction wavelet frames in L^2(R^m), where m ≤ s. From the projected dual (tight) two-direction wavelet frames in L^2(R^m), symmetric dual (tight) frames in L^2(R^m) can be obtained easily. In the end, an example is given to illustrate theoretical results. 展开更多
关键词 Two-direction refinable functions two-direction wavelets MULTIWAVELETS waveletframes biothogonal (orthogonal) SYMMETRY projection method
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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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RESEARCH ANNOUNCEMENTS Un-selfsimilar Elementary Wave and Global Solutions of a Class of Multi-dimensional Conservation Laws 被引量:3
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作者 杨小舟 《数学进展》 CSCD 北大核心 2005年第3期367-369,共3页
For Riemann problem in n(n ≥ 3) dimensional(n-D) conservation laws, dimension of equations can be only reduced one dimension by applying self-similar approach, so transformed equations are at least two dimensional (2... For Riemann problem in n(n ≥ 3) dimensional(n-D) conservation laws, dimension of equations can be only reduced one dimension by applying self-similar approach, so transformed equations are at least two dimensional (2D) equations which are also very hard although some pioneer works have been done in references [1-3]. 展开更多
关键词 维度守恒定律 黎曼几何 二维函数 自相似变换
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The Hyperspace of the Regions Below of Continuous Maps from the Converging Sequence 被引量:4
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作者 杨忠强 范玲玲 《Northeastern Mathematical Journal》 CSCD 2006年第1期46-54,共9页
Let S = {1,1/2,1/2^2,…,1/∞ = 0} and I = [0, 1] be the unit interval. We use ↓USC(S) and ↓C(S) to denote the families of the regions below of all upper semi-continuous maps and of the regions below of all conti... Let S = {1,1/2,1/2^2,…,1/∞ = 0} and I = [0, 1] be the unit interval. We use ↓USC(S) and ↓C(S) to denote the families of the regions below of all upper semi-continuous maps and of the regions below of all continuous maps from S to I and ↓C0(S) = {↓f∈↓C(S) : f(0) = 0}. ↓USC(S) endowed with the Vietoris topology is a topological space. A pair of topological spaces (X, Y) means that X is a topological space and Y is its subspace. Two pairs of topological spaces (X, Y) and (A, B) are called pair-homeomorphic (≈) if there exists a homeomorphism h : X→A from X onto A such that h(Y) = B. It is proved that, (↓USC(S),↓C0(S)) ≈(Q, s) and (↓USC(S),↓C(S)/ ↓C0(S))≈(Q, c0), where Q = [-1,1]^ω is the Hilbert cube and s = (-1,1)^ω,c0= {(xn)∈Q : limn→∞= 0}. But we do not know what (↓USC(S),↓C(S))is. 展开更多
关键词 regions below upper semi-continuity the Hilbert cube pseudo-interior strongly universal the converging sequence
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EXTENSION OF SMOOTHING FUNCTIONS TO SYMMETRIC CONE COMPLEMENTARITY PROBLEMS 被引量:2
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作者 Liu Yongjin Zhang Liwei Liu Meijiao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第2期245-252,共8页
The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity proble... The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity problems. Computable formulas for these functions and their Jacobians are derived. In addition, it is shown that these functions are Lipschitz continuous with respect to parameter # and continuously differentiable on J × J for any μ 〉 0. 展开更多
关键词 symmetric cone complementarity problem smoothing function Euclidean Jordan algebra non-interior continuation method
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A CLASS OF COMPACTLY SUPPORTED ORTHOGONAL SYMMETRIC COMPLEX WAVELETS WITH DILATION FACTOR 3 被引量:1
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作者 杨守志 沈延锋 李尤发 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1415-1425,共11页
When approximation order is an odd positive integer, a simple method is given to construct compactly supported orthogonal symmetric complex scaling function with dilation factor 3. Two corresponding orthogonal wavelet... When approximation order is an odd positive integer, a simple method is given to construct compactly supported orthogonal symmetric complex scaling function with dilation factor 3. Two corresponding orthogonal wavelets, one is symmetric and the other is antisymmetric about origin, are constructed explicitly. Additionally, when approximation order is an even integer 2, we also give a method to construct compactly supported orthogonal symmetric complex that illustrate the corresponding results. wavelets. In the end, there are several examples 展开更多
关键词 orthogonal complex wavelets approximation order SYMMETRY scaling function
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PRODUCTS OF WEIGHTED COMPOSITION AND DIFFERENTIATION OPERATORS INTO WEIGHTED ZYGMUND AND BLOCH SPACES 被引量:1
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作者 Jasbir Singh MANHAS Ruhan ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2018年第4期1105-1120,共16页
We characterize boundedness and compactness of products of differentiation op- erators and weighted composition operators between weighted Banach spaces of analytic functions and weighted Zygmund spaces or weighted Bl... We characterize boundedness and compactness of products of differentiation op- erators and weighted composition operators between weighted Banach spaces of analytic functions and weighted Zygmund spaces or weighted Bloch spaces with general weights. 展开更多
关键词 differentiation operators weighted composition operators weighted Banachspace of analytic functions Bloch-type spaces
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New Structures for Global Solutions of Two Dimensional Simplified Euler Equations
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作者 杨小舟 《数学进展》 CSCD 北大核心 2005年第4期509-511,共3页
1 Introduction and Main Results Systems of two-dimensional (2D) hyperbolic conservation laws are more accurate modeling of many sophisticated physical phenomena. Although people have made great progress in one dimensi... 1 Introduction and Main Results Systems of two-dimensional (2D) hyperbolic conservation laws are more accurate modeling of many sophisticated physical phenomena. Although people have made great progress in one dimensional conservation laws, there are relatively fewer results[1] on 2D systems since many methods valid in one dimensional case can not be applied in 2D cases, 2D problems are still very difficult to be studied. 展开更多
关键词 EULER方程 球形解 单一性 二维方程
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A NEW CHARACTERIZATION OF Q_p~# FUNCTIONS
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作者 乌兰哈斯 李晓南 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期583-588,共6页
A new characterization of Q#p is given, which implies immediately a known result. Also, the authors consider a class Νp of bounded characteristic with order p, 0 < p < ∞, in the unit disk and give some relatio... A new characterization of Q#p is given, which implies immediately a known result. Also, the authors consider a class Νp of bounded characteristic with order p, 0 < p < ∞, in the unit disk and give some relationship between it and other classes of meromorphic functions. This paper answers partly a question mentioned by Aulaskari and Lappan. 展开更多
关键词 Normal functions Q#p bounded characteristic the Green function
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Construction of nonseparable orthonormal compactly supported wavelet bases for L^2(R^d)
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作者 YANG Shou-zhi LIN Jun-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第2期205-224,共20页
Suppose M and N are two r×r and s×s dilation matrices,respectively.LetΓM andΓN represent the complete sets of representatives of distinct cosets of the quotient groups M-T Zr/Zr and N-T Zs/Zs,respectively.... Suppose M and N are two r×r and s×s dilation matrices,respectively.LetΓM andΓN represent the complete sets of representatives of distinct cosets of the quotient groups M-T Zr/Zr and N-T Zs/Zs,respectively.Two methods for constructing nonseparable Ω-filter banks from M-filter banks and N-filter banks are presented,where Ω is a(r+s) ×(r+s) dilation matrix such that one of its complete sets of representatives of distinct cosets of the quotient groups Ω-T Zr+s/Zr+s areΓΩ={[γT h,ζ T q] T:γh∈ΓM,ζq∈ΓN}.Specially,Ω can be [MΘ0N],whereΘis a r×s integer matrix with M-1Θbeing also an integer matrix.Moreover,if the constructed filter bank satisfies Lawton's condition,which can be easy to verify,then it generates an orthonormal nonseparable Ω-wavelet basis for L2(Rr+s).Properties,including Lawton's condition,vanishing moments and regularity of the new Ω-filter banks or new Ω-wavelet basis are discussed then.Finally,a class of nonseparable Ω-wavelet basis for L2(Rr+1) are constructed and three other examples are given to illustrate the results.In particular,when M=N=2,all results obtained in this paper appeared in[1]. 展开更多
关键词 filter bank nonseparable orthonormal wavelet basis Lawton's condition vanishing moment regularity.
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On the Behaviors of Hyperspace Topologies for Subspaces
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作者 侯吉成 高智民 《Northeastern Mathematical Journal》 CSCD 2003年第4期295-305,共11页
For a topological space X we denote by CL(X) the collection of all nonempty closed subsets of X. Suppose we have a map T which assigns in some coherent way to every topological space X some topology T(X) on CL(X). In ... For a topological space X we denote by CL(X) the collection of all nonempty closed subsets of X. Suppose we have a map T which assigns in some coherent way to every topological space X some topology T(X) on CL(X). In this paper we study continuity and inverse continuity of the map iA,X :(CL(A),T{A)) → (CL(X),T(X)) defined by iA,x(F) = F whenever F ∈CL(A), for various assignment T; in particular, for locally finite topology, upper Kuratowski topology, and Attouch-Wets topology, etc. 展开更多
关键词 hyperspace topology SUBSPACE inverse continuity
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Construction of Balanced Orthogonal Nonseparable Multiwavelets
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作者 XIE Chang-zhen 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第3期462-467,共6页
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DE RHAM DECOMPOSITION FOR RIEMANNIAN MANIFOLDS WITH BOUNDARY
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作者 余成杰 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期51-62,共12页
In this paper,we extend the classical de Rham decomposition theorem to the case of Riemannian manifolds with boundary by using the trick of the development of curves.
关键词 de Rham decomposition parallel distribution development of curve
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DE MORGAN ALGEBRAS WITH DOUBLE DEMI-PSEUDOCOMPLEMENTATION 被引量:4
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作者 方捷 王雷波 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1613-1623,共11页
The variety ddpM of de Morgan algebras with double demi-pseudocomplementation consists of those algebras (L; ∧ , ∨ , , , + , 0, 1) of type (2, 2, 1, 1, 1, 0, 0) where (L; ∧ , ∨ , , 0, 1) is a de Morgan alge... The variety ddpM of de Morgan algebras with double demi-pseudocomplementation consists of those algebras (L; ∧ , ∨ , , , + , 0, 1) of type (2, 2, 1, 1, 1, 0, 0) where (L; ∧ , ∨ , , 0, 1) is a de Morgan algebra, (L; ∧ , ∨ , , + , 0, 1) is a double demi-p-lattice and the operations x → x , x → x and x → x + are linked by the identities x = x , x + = x + and x + = x + . In this paper, we characterize congruences on a ddpM-algebra, and give a description of the subdirectly irreducible algebras. 展开更多
关键词 de Morgan algebra double demi-pseudocomplemented algebra subdirectly irreducible
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CYCCYCLIC VECTORS AND CELLULAR INDECOMPOSABLE OPERATORS ON Q_p SPACES 被引量:2
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作者 叶善力 娄增建 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期434-440,共7页
We identify the functions whose polynomial multiples are weak* dense in Qp spaces and prove that if |f(z)| ≥ |g(z)| and g is cyclic in Qp, then f is cyclic in Qp. We also show that the multiplication operato... We identify the functions whose polynomial multiples are weak* dense in Qp spaces and prove that if |f(z)| ≥ |g(z)| and g is cyclic in Qp, then f is cyclic in Qp. We also show that the multiplication operator Mx on Qp spaces is cellular indecomposable. 展开更多
关键词 Cyclic vectors Outer functions Cellular indecomposable Qp spaces
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WEIGHTED COMPOSITION OPERATORS ON WEIGHTED DIRICHLET SPACES 被引量:1
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作者 刘小松 娄增建 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1119-1126,共8页
We characterize the boundedness and compactness of weighted composition operators on weighted Dirichlet spaces in terms of Nevanlinna counting functions and Caxleson measure.
关键词 weighted composition operator weighted Dirichlet space s-Carleson mea-sure Nevanlinna counting function
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CRITERIA FOR AN ANALYTIC FUNCTION BELONGING TO THE Q_K SPACES 被引量:1
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作者 乌兰哈斯 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期33-44,共12页
The author gives a mild integral condition in a nondecreasing function K : [0, ∞) → [0, ∞), which is sufficient and the best possible to ensure that f is a Bloch function if and only if f belongs to QK, a Mbius-inv... The author gives a mild integral condition in a nondecreasing function K : [0, ∞) → [0, ∞), which is sufficient and the best possible to ensure that f is a Bloch function if and only if f belongs to QK, a Mbius-invariant space of functions analytic in the unit disk. Their contributions are slight improvements of known results, and the proofs presented here are independently developed. The corresponding results for meromorphic case are also given. 展开更多
关键词 Areally mean q-valent circumferentially mean q-valent QK spaces
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D_(K) SPACES AND CARLESON MEASURES 被引量:1
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作者 李东行 乌兰哈斯 赵如汉 《Acta Mathematica Scientia》 SCIE CSCD 2022年第3期1103-1112,共10页
We give some characterizations of Carleson measures for Dirichlet type spaces by using Hadamard products.We also give a one-box condition for such Carleson measures.
关键词 DK space Hadamard product mean growth Carleson measure
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A NOTE ON LI-YAU-TYPE GRADIENT ESTIMATE
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作者 余成杰 赵菲菲 《Acta Mathematica Scientia》 SCIE CSCD 2019年第4期1185-1194,共10页
In this article, we obtain Li-Yau-type gradient estimates with time dependent parameter for positive solutions of the heat equation that are different with the estimates by Li-Xu [21] and Qian [23]. As an application ... In this article, we obtain Li-Yau-type gradient estimates with time dependent parameter for positive solutions of the heat equation that are different with the estimates by Li-Xu [21] and Qian [23]. As an application of the estimate, we also obtained slight improvements of Davies' Li-Yau-type gradient estimate. 展开更多
关键词 HEAT equation Li-Yau-type gradient ESTIMATE HEAT KERNEL
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