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Acta Mathematica Sinica, Chinese Series 2010 Vol.53

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Weak Morita Equivalence of Symplectic Groupoids and Orbifold Fundamental Group
Yi Wu LIN
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 1-8.   DOI: 10.12386/A2010sxxb0001
Abstract3543)      PDF(pc) (435KB)(1090)       Save

We discuss weak Morita equivalence of the symplectic orbifold groupoids, and show that two symplectic orbifold groupoids are weak Morita equivalent if and only if they have isomorphic orbifold fundamental groups.

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Enumeration of Rooted Unicursal Planar Maps
Shu De LONG, Jun Liang CAI
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 9-16.   DOI: 10.12386/A2010sxxb0002
Abstract2652)      PDF(pc) (412KB)(1102)       Save

This paper provides some functional equations satisfied by the generating functions for unicursal planar maps rooted in a vertex of odd valency with the number of edges, the valencies of rooted vertex and nonrooted odd-valent vertex of the maps as three parameters. Moreover, explicit expressions of these functions are also derived. Two of them is summation-free.

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Local 3-Cocycles of Nest Subalgebras of Factor von Neumann Algebras
Hong Xia LI, Jian Hua ZHANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 17-24.   DOI: 10.12386/A2010sxxb0003
Abstract2632)      PDF(pc) (374KB)(1015)       Save

It is proved that every weakly continuous local 3-cocycle of a nest subalgebra of a factor von Neumann algebra with coeffcients on a unital dual bimodule is a 3-cocycle.

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Quasi-Lp-Mixed Intersection Bodies
Zhi Gang YU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 25-36.   DOI: 10.12386/A2010sxxb0004
Abstract2632)      PDF(pc) (472KB)(1013)       Save
In 1988, Lutwak first brought into being the concept of Intersection Bodies, based on which, complemented by that of Quasi-Lp-Intersection Bodies, the present paper proposes a new idea of Quasi Lp-mixed Intersection Bodies. With the help of the dual Lp-Mixed Quermassintegrals theory and some related inequalities, the paper gives the Lp-Busemann Intersetion Inequality, establishes some dual Brunn--Minkowski inequalities and their isolated forms for Lp-mixed intersection body about Lp-radial combination and Lp-harmonic Blaschke combination, as well as lodges a discussion on the problem of Quasi-Lp-mixed Intersection Bodies' monotonicity.

 

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On the Diophantine Equations (a-1)x2+(91a+9)=4an
Zhi Gang LI, Ping Zhi YUAN
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 37-44.   DOI: 10.12386/A2010sxxb0005
Abstract3018)      PDF(pc) (442KB)(1188)       Save
In this paper, we prove that if a≥2 is an integer and a≠5, the equations (a-1)x2+(91a+9)=4an have no positive integer solutions (x, n) with 2 ? n; if a=5, the equation has the only solution (x,n)=(3,3) with 2 n.

 

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Weakly Convex Set and W-Sun Set in Banach Spaces
Wei Bo GUAN, Wen SONG
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 45-50.   DOI: 10.12386/A2010sxxb0006
Abstract2746)      PDF(pc) (374KB)(1122)       Save

Under the frame of the smooth Banach spaces, we introduce the notions of the weakly convex set and the W-sun set and present their properties and applications in approximation problems.

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The Ergodicity of Partially Hyperbolic Systems with Center Bunching
Yun Hua ZHOU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 51-54.   DOI: 10.12386/A2010sxxb0007
Abstract2450)      PDF(pc) (420KB)(1022)       Save
Let M be a smooth compact Riemmannian manifold, f be a C2 partially hyperbolic diffeomorphism preserving volume. If f is essential accessible and the central exponents satisfy center bunching condition for all invariant measure, then f is ergodic. Especially, if for all invariant measure of f, the central exponents are zero, then essential accessibility implies ergodicity. These results partially answer two open problems.

 

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Existence and Uniqueness of Fixed Points for Mixed Non-Monotone Binary Operators in Ordered Banach Spaces and Its Applications
Pei Guo ZHANG, Li Shan LIU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 55-60.   DOI: 10.12386/A2010sxxb0008
Abstract3548)            Save
By using the cone theory and the Banach contraction mapping principle, the existence and uniqueness theorem of fixed points for mixed non-monotone binary operators in ordered Banach spaces are investigated under more general condition. As an application, an existence and uniqueness theorem of solutions for initial value problems of second order nonlinear integro-differential equations of Volterra type in Banach spaces is given. The results presented here improve and generalize some known results.

 

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ε-Approximate Orthogonality Preserving Mappings
Liang KONG, Huai Xin CAO
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 61-66.   DOI: 10.12386/A2010sxxb0009
Abstract4159)      PDF(pc) (319KB)(933)       Save
For an ε-approximate orthogonality preserving mapping T, an estimate of is obtained and some sufficient conditons for a linear mapping to be an ε-approximate orthogonality preserving mapping are given. Secondly, the stability of an ε-approximate orthogonality preserving linear mapping is discussed. Lastly, the perturbations of ε-approximate orthogonality preserving linear mappings are studied.  
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Weighted Composition Operator from Bergman-Type Spaces into Bers-Type Spaces
Zhi Jie JIANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 67-74.   DOI: 10.12386/A2010sxxb0010
Abstract2982)            Save
This paper investigates weighted composition operator from Bergman-type space into Bers-type space, and some necessnary and sufficient conditions of weighted composition operator to be bounded and compact and weak compact are obtained. The paper also gives the angular derivative rule of compactness of weighted composition operators. The paper also talks about weighted composition operator with closed range and a sufficient condition is given.

 

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Property (ω) and Weyl Type Theorem
Xiao Hong CAO, Chen Hui SUN, Lei DAI
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 75-82.   DOI: 10.12386/A2010sxxb0011
Abstract3400)      PDF(pc) (441KB)(1175)       Save
In this note we study the property (ω), a variant of Weyl's theorem introduced by Rakocevic, by means the new spectrum. We establish for a bounded linear operator defined on a Banach space a sufficient and necessary condition for which both property (ω) and a-Weyl's theorem hold. As a consequence of the main result, we study the property (ω) and a-Weyl's theorem for H(P) operators.

 

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On the Diophantine Equation y2=px(x2+2)
Li Min CHEN
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 83-86.   DOI: 10.12386/A2010sxxb0012
Abstract2866)      PDF(pc) (229KB)(1112)       Save
Let p be an odd prime with p≠3. In this paper we prove that if p≡5 or 7(mod 8), then the equation y2=px(x2+2) has no positive integer solution (x,y); if p≡1(mod 8), then the equation has at most one solution; if p≡3(mod 8), then the equation has at most two solutions.

 

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Estimates for Commtators of Marcinkiewicz Integrals with Hörmander-Type Condition in Non-Homogeneous Spaces
Liang LI, Yin Sheng JIANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 87-96.   DOI: 10.12386/A2010sxxb0013
Abstract2858)      PDF(pc) (518KB)(962)       Save
Let μ be a positive Radon measure on which may be non doubling. The only condition that μ must satisfy is μ(B(x,r))≤C0 rn for all , r>0 and some fixed n∈(0,d]. In this paper, the authors establish the boundedness of the commutator generated by the Lipβ(μ)(0<β) function and the Marcinkiewicz integral with kernel satisfying certain slightly stronger Hörmander-type condition, respectively, from Lp(μ) to Lq(μ) with 1<pn/β and 1/q=1/p-β/n, from the space Lp(μ) to Lipβ-n/p(μ) and from the space Ln/β(μ) to RBMO(μ). Some of the results are also new even for the classical Marcinkiewicz integral.  
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On Approximation by Shepard--Lagrange Operators
Dan Sheng YU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 97-108.   DOI: 10.12386/A2010sxxb0014
Abstract2486)      PDF(pc) (443KB)(949)       Save
We establish direct and inverse results of the approximation by the Shepard--Lagrange operators. It was shown that we can use higher modulus of smoothness to characteristic the approximation of the Shepard--Lagrange operators, and thus the Shepard--Lagrange operators have better approximation properties than the usual Shepard operators. Furthermore, the higher modulus of smoothness involves a very general class of step functions, which can not be obtained by polynomial approximation.

 

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Strong Converse Inequality for Left Bernstein--Kantorovich Quasi-Interpolants
Shun Shen GUO, Guo Fen LIU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 109-116.   DOI: 10.12386/A2010sxxb0015
Abstract2531)      PDF(pc) (351KB)(835)       Save
For the left Bernstein--Kantorovich quasi-interpolants Kn(2r-1)f, we prove that for some l, This is a strong converse inequality of type B.  
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On the Mass Distribution Principle and Hausdorff Measure for the Self-Similar Sets and Applications
Shao Yuan XU, Zuo Ling ZHOU, Wei Yi SU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 117-124.   DOI: 10.12386/A2010sxxb0016
Abstract2841)      PDF(pc) (445KB)(1072)       Save
In this paper, the mass distribution principle for the self-similar sets satisfying the open set condition (OSC) is set up. As an application, we obtain a new method for computing the exact value of the Hausdorff measure for a class of self-similar sets satisfying OSC. In addition, we give two examples to show that the new method is effective and workable to compute the exact values of the Hausdorff measures of a class of self-similar sets satisfying OSC.

 

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Strong Convergence Rate for Slope Change Point Estimator
Chang Chun TAN, Bai Qi MIAO, Hui Liu LI
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 125-134.   DOI: 10.12386/A2010sxxb0017
Abstract2698)      PDF(pc) (424KB)(931)       Save
In this paper, the problem of slope-change point is considered. The consistency and convergence rate of change point estimator are presented when the error distribution are not normal. At the same time, the Op convergence rate of change point estimator is obtained at the condition of local alternative hypothesis.

 

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A Note on the Ideal Class Number Problem for Quadratic Function Fields
Su HU, Zong Wen YU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 135-140.   DOI: 10.12386/A2010sxxb0018
Abstract3085)      PDF(pc) (362KB)(895)       Save
Using Pell equations on , we give a new proof of the well-known fact that if the ideal class number of a real quadratic function field equals to 1, then D must be P or QR, where P,Q,R are monic and irreducible, and Q,R have odd degrees.  
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A Weighted Estimate for the Maximal Commutators on Spaces of Homogeneous Type
Guo En HU, Wei Hong WANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 141-152.   DOI: 10.12386/A2010sxxb0019
Abstract2917)      PDF(pc) (490KB)(942)       Save
In this paper, a weighted norm inequality with general weights is established for the maximal operator associated with the commutators of singular integral operators on spaces of homogeneous type.

 

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Viscosity Approximation Methods for Equilibrium Problems and Fixed Point Problems with Its Applications
Bao Hua GUO , Sheng Hua WANG , Hai Yun ZHOU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 153-164.   DOI: 10.12386/A2010sxxb0020
Abstract2325)      PDF(pc) (436KB)(836)       Save
We introduce a new iterative scheme by viscosity approximation method for obtaining a common element of the set of solutions of an equilibrium problem and the set of fixed points of a nonexpansive mapping and an inverse-strongly monotone mapping in a Hilbert space. Then a strong convergence theorem is obtained. As its application, we give a strong convergence theorem for nonexpansive mappings and strictly pseudo-contractive mappings in a Hilbert space.

 

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The Martingale Pricing for Convertible Bond with Risk in Jump-Diffusion Model
Dan ZHU, Xiang Qun YANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 165-170.   DOI: 10.12386/A2010sxxb0021
Abstract2346)      PDF(pc) (524KB)(928)       Save

This paper studies the pricing problem of the convertible bond with risk in Jump-diffusion model. Under the hypothesis that the stock price is satisfied to geometic Brown motion , the pricing formulas of the convertible bond are obtained by means of Martingale approach (risk-neutral valuation).

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The Global L2 Stability of Large Solutions to Three Dimensional Boussinesq Equations
Xian Jin LI, Quan Sen JIU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 171-186.   DOI: 10.12386/A2010sxxb0022
Abstract4167)      PDF(pc) (510KB)(836)       Save
In this paper, we mainly study the global L2 stability for large solutions to the Boussinesq equations in three-dimensional bounded or unbounded domains. Under suitable conditions of the large solutions, it is shown that the large solutions are stable. And we obtain the equivalent condition of this main stability condition. Moreover, the global existence and the stability of two-dimensional Boussinesq equations under three-dimensional perturbations are also established.

 

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Hausdorff Dimensions of Julia Sets of Families of Transcendental Entire Functions
Cun Ji YANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 187-198.   DOI: 10.12386/A2010sxxb0023
Abstract2643)      PDF(pc) (482KB)(902)       Save
By a family of transcendental entire functions, Stallard shows that the Hausdorff dimensions of Julia sets of those functions have greatest lower bound equal to one.We prove that the Hausdorff dimensions of Julia sets of two families of transcendental entire functions have greatest lower bound equal to one. On the other hand, for any d∈(1, 2), we prove that there exists a family of transcendental entire functions with Hausdorff dimension equal to d.

 

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Squares in
Zhong Feng ZHANG, Ping Zhi YUAN
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 199-204.   DOI: 10.12386/A2010sxxb0024
Abstract2380)            Save
In this paper, we prove that the product (f(x)=ax2+bx+cZ[x] is an irreducible quadratic polynomial) is not a square for sufficiently large n.  
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Points on the Elliptic Curve y2=x3+27x-62
Hua Ming WU
Acta Mathematica Sinica, Chinese Series    2010, 53 (1): 205-208.   DOI: 10.12386/A2010sxxb0025
Abstract2565)      PDF(pc) (307KB)(936)       Save
Using some known results of quartic diophantine equations with elementary number theory methods, we prove that the elliptic curve y2=x3+27x-62 has only the integral points (x, y)=(2, 0) and (28844402, ±154914585540).

 

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Characterizations and Perturbations of Effective Sequences in a Hilbert Space
Ye ZHANG, Huai Xin CAO
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 209-218.   DOI: 10.12386/A2010sxxb0026
Abstract2495)      PDF(pc) (426KB)(1089)       Save

In this paper, the effective sequences in a Hilbert space are discussed and by introducing the adjoint sequence of a sequence, an equivalent characterization of an effective sequence is presented. Next, some properties of linear operators preserving the effectiveness of effective sequences are discussed. It is proved that a linear operator maps every effective sequence as an effective sequence if and only if it is a unitary. Finally, we give a necessary and sufficient condition for a sequence obtained by adding a unit vector into an orthonormal basis to be an effective sequence.

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A Note on Generalized Property (ω)
Lei DAI, Xiao Hong CAO, Chen Hui SUN
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 219-226.   DOI: 10.12386/A2010sxxb0027
Abstract3396)      PDF(pc) (441KB)(943)       Save

In this note we study the generalized property (ω), a variant of generalized Weyl's theorem, by means of the new spectrum. We establish for a bounded linear operator defined on a Banach space a sufficient and necessary condition for which generalized property (ω) holds. As a consequence of the main result, the stability of generalized property (ω) is considered.

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Almost Periodic Solutions of Second-Order Neutral Delay-Differential Equations with Piecewise Constant Argument
Li WANG, Chuang Yi ZHANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 227-232.   DOI: 10.12386/A2010sxxb0028
Abstract2689)      PDF(pc) (415KB)(892)       Save
In this paper, we investigate the existence of\ almost periodic solutions of second-order neutral delay-differential equations with piecewise constant argument of the form (x(t)+px(t-1))"=qx(2[(t+1)/2])+f(t), where [·] denotes the greatest integer function, p, q are nonzero real constants and |p|=1, q≠-4, f(t) is almost periodic.

 

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Sufficient Conditions for the Existence of Exponential Attractors for Lattice Systems and Applications
Cai Di ZHAO, Sheng Fan ZHOU
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 233-242.   DOI: 10.12386/A2010sxxb0029
Abstract3272)      PDF(pc) (516KB)(934)       Save
We first recast some sufficient conditions for the existence of exponential attractors for general lattice dynamical systems. Then we apply the result to the following nonlinear Schrödinger equations on infinite lattices: Under some conditions on γ, κ,δ,σ and gm, the existence of exponential attractors is established.  
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Boundedness of Commutators of Singular Integral Operators Satisfying Condition H(m)
Can Qin TANG, Bo Lin MA
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 243-250.   DOI: 10.12386/A2010sxxb0030
Abstract3087)      PDF(pc) (435KB)(1028)       Save
In this paper, the boundedness of commutators associated with singular integral operators T satisfying H(m) with Lipschitz functions from Lp(Rn) to some Lq(Rn) spaces is obtained. The boundedness on Hardy space is also considered. The results are applied to obtain the boundedness of commutators of Riesz transforms associated with Schrödinger operator and Lipschitz functions.

 

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A Representation Theorem for Two Types of Statistical Convergence
Xian Geng ZHOU, Min ZHAN
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 251-256.   DOI: 10.12386/A2010sxxb0031
Abstract2257)      PDF(pc) (372KB)(1064)       Save
In this paper proves some representation theorems of Δ(Δm)-statistical convergence and double sequence (double sequence double Lacunary) statistical convergence in Banach space X.

 

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H-Oscillation of Impulsive Vector Neutral Parabolic Partial Differential Equations
Li Ping LUO, Yuan Hong YU
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 257-262.   DOI: 10.12386/A2010sxxb0032
Abstract3395)      PDF(pc) (429KB)(942)       Save
The oscillation of a class of impulsive vector neutral parabolic partial differential equations is studied. To change the multi-dimensional oscillation problems into the problems of which one-dimensional impulsive delay differential inequalities haven't eventually positive solution by employing the concept of H-oscillation introduced by Domslak and the method of reducing dimension with the inner product, some sufficient criteria for H-oscillation of all solutions of the equations are established under Dirichlet boundary value condition, where H is a unit vector of RM.

 

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The Hypersurfaces in S5 with Constant Para-Blaschke Eigenvalues
Ding Xing ZHONG, Hong An SUN, Ting Fang ZHANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 263-278.   DOI: 10.12386/A2010sxxb0033
Abstract2369)      PDF(pc) (567KB)(879)       Save
Let x:MSn+1 be a hypersurface in the (n+1)-dimensional unit sphere Sn+1 without umbilics. Four basic invariants of x under the Moebius transformation group in Sn+1 are a Riemannian metric g called Moebius metric, a 1-form Φ called Moebius form, a symmetric (0,2) tensor A called Blaschke tensor and symmetric (0,2) tensor B called Moebius second fundamental form. Let D =AB, where λ is a constant. Then D is a symmetric (0,2) tensor and a Moebius invariant. D is called Para-Blaschke tensor of x. Li and Wang have studied the hypersurfaces x:MSn+1, which satisfy: (i) Φ=0, (ii) AB+μg=0 for some functions λ and μ on M; they have proved that λ and μ must be constants and have classified the hypersurfaces; in fact, they have classified the hypersurfaces which satisfy: (i) Φ=0, (ii) D has only one distinct constant eigenvalue. In this paper, We classify the hypersurfaces x:MS5, which satisfy: (i) Φ=0, (ii) D has constant eigenvalues for some constants λ.

 

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Construction of Paraunitary Symmetric Matrix and Parametrization of Symmetric and Orthogonal Multiwavelets Filter Banks
You Fa LI, Shou Zhi YANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 279-290.   DOI: 10.12386/A2010sxxb0034
Abstract3272)      PDF(pc) (578KB)(912)       Save

Paraunitary matrices play a very important role in construction of wavelets, multiwavelets and frames. In this paper, we give an explicit algorithm for constructing paraunitary symmetric matrices (p.s.m. for short), whose components are symmetric or antisymmetric polynomials. Based on the constructed p.s.m. and the given orthogonal and symmetric multiwavelets (o.s.m. for short), parametrization of o.s.m. filter banks is given. Appropriately selecting some parameters, we can obtain o.s.m. with some additionally desirable properties such as Armlet. To embody our results, we construct a family of symmetric Chui--Lian Armlet filters.

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The Relation Between Solutions of Higher Order Differential Equation with Functions of Small Growth
Jun Feng XU, Hong Xun YI
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 291-296.   DOI: 10.12386/A2010sxxb0035
Abstract4276)      PDF(pc) (404KB)(1042)       Save

In this paper, we use a new lemma to investigate the relation between solutions, their 1st, 2nd derivatives, differential polynomial of differential equations with function of small growth.

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On Je?manowícz’s Conjecture Concerning Pythagorean Numbers
Yong Zhong HU, Ping Zhi YUAN
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 297-300.   DOI: 10.12386/A2010sxxb0036
Abstract2680)      PDF(pc) (379KB)(998)       Save
We show that when a=n+1, b=2n(n+1), c=2n(n+1)+1 with n positive integer, the equation ax+by=cz has only the positive integer solution (x,y,z)=(2,2,2). The proof is based on using the theorem about the existence of primitive divisors of Lucas numbers due to Bilu, Hanrot & Voutier and some fine results on the representation of the solutions of quadratic diophantine equations.

 

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On Lp-Mixed Centroid Bodies and Dual Lp-Mixed Centroid Bodies
Tong Yi MA
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 301-314.   DOI: 10.12386/A2010sxxb0037
Abstract2631)      PDF(pc) (513KB)(842)       Save
In this paper, the three concepts of Lp-mixed centroid bodies Γp,iK and dual Lp-mixed centroid bodies Γ-p,iK and Lp-mixed harmonic Blaschke add of star bodies are introduced. The Shephard's question of Lp-mixed centroid bodies and dual Lp-mixed centroid bodies are solved succeed. In addition, the Brunn--Minkowski inequalities of the quermassintegrals and dual quermassintegrals of Lp-mixed centroid bodies associated with Lp-mixed harmonic Blaschke add are established, respectively. They extend some results of before document.  
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Linear Maps Preserving Projections of Products of Operators
Guo Xing JI, Fan Lian QU
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 315-322.   DOI: 10.12386/A2010sxxb0038
Abstract2993)      PDF(pc) (413KB)(1037)       Save
Let B(H) be the algebra of all bounded linear operators on a complex Hilbert space H with dim H≥2. It is proved that a linear surjective map φ on B(H) preserves the nonzero projections of products of two operators if and only if there is a unitary operator U in B(H) such that φ(X)=λU*XU, ?XB(H) for some constants λ with λ2=1. Related results for linear surjective maps preserving Jordan triple products of two operators are also obtained.

 

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Chebyshev Polynomials on Julia Set and Equipotential Curves
Ying Qing XIAO, Wei Yuan QIU
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 323-328.   DOI: 10.12386/A2010sxxb0039
Abstract3036)      PDF(pc) (404KB)(967)       Save
Let P be a monic polynomial of degree d, and JP be the Julia set of P. We obtain the dn-th Chebyshev polynomials on the Julia set JP and on the equipotential curves ΓP(R) of JP, and give an example to show that they are not always equal.

 

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Bartlett's Decomposition and Generalized Inferences on the Means of Several Multivariate Normal Populations
Yong Hui FAN, Song Gui WANG
Acta Mathematica Sinica, Chinese Series    2010, 53 (2): 329-340.   DOI: 10.12386/A2010sxxb0040
Abstract2319)      PDF(pc) (599KB)(846)       Save
Inference on the mean vectors of several multivariate normal populations is an old and interesting problem. In this paper, by the distribution of the Bartlett's decomposition of sample covariance matrices, the concepts of an exact tests are proposed. Simulation shows these tests are more powerful than the existing tests. Also, by the Bartlett's decomposition of sample covariance matrices and the sample mean vectors, two generalized tests and a new traditional test are proposed to test the common mean of several multivariate normal populations. Simulation shows that the type I error probability of these tests is less than the nominal level and has more powers.

 

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