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    20 September 2010, Volume 30 Issue 5 Previous Issue    Next Issue
    Articles
    TANGENT UNIT-VECTOR FIELDS: NONABELIAN HOMOTOPY INVARIANTS AND THE DIRICHLET ENERGY
    A. Majumdar, J.M. Robbins, M. Zyskin
    Acta mathematica scientia,Series B. 2010, 30 (5):  1357-1399.  DOI: 10.1016/S0252-9602(10)60131-2
    Abstract ( 697 )   RICH HTML PDF (430KB) ( 1067 )   Save

    Let O be a closed geodesic polygon in S2.  Maps from O into S2 are said to satisfy tangent boundary conditions if the edges of O are mapped into the geodesics which contain them. Taking O to be an octant of S2, we compute the infimum Dirichlet energy ε(H) for continuous maps satisfying tangent boundary conditions of arbitrary homotopy type H. The expression for ε(H) involves a topological invariant -- the spelling length -- associated with the (non-abelian) fundamental group of the n-times punctured two-sphere, π1(S2 - s1, …, sn}, *). The lower bound for ε(H) is obtained from combinatorial group theory arguments, while the upper bound is obtained by constructing explicit representatives which, on all but an arbitrarily small subset of O, are alternatively locally conformal or anticonformal. For conformal and anticonformal classes (classes containing wholly conformal and anticonformal representatives respectively),  the expression for ε(H) reduces to a previous result involving the degrees of a set of regular values s1, …, sn in the target S2 space.  These degrees may be viewed as invariants associated with the abelianization of π1(S2 -{s1, …, sn}, *). For nonconformal classes, however, ε(H) may be strictly greater than the abelian bound.  This stems from the fact that, for nonconformal maps, the number of preimages of certain regular values may necessarily be strictly greater than the absolute value of their degrees.

    This work is motivated by the theoretical modelling of nematic liquid crystals in confined polyhedral geometries. The results imply new lower and upper bounds for the Dirichlet energy (one-constant Oseen-Frank energy) of reflection-symmetric tangent unit-vector fields in a rectangular prism.

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    LEVITIN-POYAK WELL-POSEDNESS OF EQUILIBRIUM PROBLEMS GENERALIZED VECTOR WITH FUNCTIONAL CONSTRAINTS
    WANG Gang, HUANG Xue-Xiang, ZHANG Jie, CHEN Guang-Ya
    Acta mathematica scientia,Series B. 2010, 30 (5):  1400-1412.  DOI: 10.1016/S0252-9602(10)60132-4
    Abstract ( 842 )   RICH HTML PDF (184KB) ( 1291 )   Save

    In this article, we study Levitin-Polyak type well-posedness for generalized vector equilibrium problems with abstract and functional constraints. Criteria and characterizations for these types of well-posednesses are given.

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    REMARK ON THE BLOW-UP CRITERION OF STRONG SOLUTIONS TO THE NAVIER-STOKES EQUATIONS IN MULTIPLIER SPACES
    Sadek Gala
    Acta mathematica scientia,Series B. 2010, 30 (5):  1413-1418.  DOI: 10.1016/S0252-9602(10)60133-6
    Abstract ( 823 )   RICH HTML PDF (142KB) ( 1055 )   Save

    In this note, we prove that Xr ( 0<r<1)  norm of the vorticity controls the blow-up phenomena of strong solutions to the Navier-Stokes equations in R3.

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    DECOMPOSITION THEOREMS FOR Qp SPACES WITH SMALL SCALE p ON THE UNIT BALL OF Cn
    PENG Ru, OUYANG-Cai-Heng
    Acta mathematica scientia,Series B. 2010, 30 (5):  1419-1428.  DOI: 10.1016/S0252-9602(10)60134-8
    Abstract ( 740 )   RICH HTML PDF (177KB) ( 1035 )   Save

    This article is devoted to studying the decomposition of functions of Qp spaces, which unify Bloch space and BMOA space in the scale of p. A decomposition theorem is established for Qp spaces with small scale p, n-1/ n <p ≤1 by means of p-Carleson measure and the Bergman metric on the unit ball of Cn. At the same time, a decomposition theorem for Qp, 0 spaces is given as well.

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    OPTIMAL LOGISTICS FOR MULTIPLE JEEPS
    CHEN Wen-Lei, DING Yi-Ming, FAN Wen-Tao
    Acta mathematica scientia,Series B. 2010, 30 (5):  1429-1439.  DOI: 10.1016/S0252-9602(10)60135-X
    Abstract ( 659 )   RICH HTML PDF (172KB) ( 1122 )   Save

    We consider  variations of the classical jeep problems: the optimal logistics for a caravan of jeeps which travel together in the desert. The main purpose is to arrange the travels for the one-way trip and the round trip of a caravan of jeeps so that   the chief jeep visits  the farthest destination. Based on the dynamic program principle, the maximum distances for the caravan when only  part of the jeeps should return and when all drivers should return are obtained. Some related results such as the efficiency of the abandoned jeeps, and the advantages of more jeeps in the caravan are also presented.

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    MARKOV SKELETON PROCESS IN PERT NETWORKS
    KONG Xiang-Xing, ZHANG Xuan, HOU Zhen-Ting
    Acta mathematica scientia,Series B. 2010, 30 (5):  1440-1448.  DOI: 10.1016/S0252-9602(10)60136-1
    Abstract ( 705 )   RICH HTML PDF (161KB) ( 1108 )   Save

    In this article, we investigate Programming Evaluation and Review Technique networks with independently and generally distributed activity durations. For any path in this network, we select all the activities related to this path such that the completion time of the sub-network (only consisting of all the related activities) is equal to the completion time of this path. We use the elapsed time as the supplementary variables
    and model this sub-network as a Markov skeleton process, the state space is related to the sub-network structure. Then use the backward equation to compute the distribution of the sub-network's completion time, which is an important rule in project management and scheduling.

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    ON A SUBCLASS OF CLOSE TO CONVEX FUNCTIONS
    PENG Zhi-Gang
    Acta mathematica scientia,Series B. 2010, 30 (5):  1449-1456.  DOI: 10.1016/S0252-9602(10)60137-3
    Abstract ( 786 )   RICH HTML PDF (145KB) ( 1788 )   Save

    Let C'(α,β) be the class of functions f(z)=zn=2anzn analytic in D={z: |z|<1}, satisfying for some convex function g(z) with g(0)=g'(0)-1=0 and for all z in D the condition

    |{zf'(z)/{g(z) -1/zf'(z)/{g(z)}+(1-2α)|<β

    for some α,β(0≤α<1, 0<β≤1). A sharp coefficient estimate, distortion theorems and radius of convexity are determined for the class C'(α, β). The results extend the work of C. Selvaraj.

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    GENERIC WARPED PRODUCT SUBMANIFOLDS %OF LOCALLY CONFORMAL KEAHLER MANIFOLDS
    Nargis Jamal??20Khalid Ali Khan, Viqar Azam Khan
    Acta mathematica scientia,Series B. 2010, 30 (5):  1457-1468.  DOI: S0252-9602(10)60138-5
    Abstract ( 635 )   RICH HTML PDF (175KB) ( 1365 )   Save

    Warped product manifolds are known to have applications in physics. For instance, they provide an excellent setting to model space-time near a black hole or a massive star (cf. [9]). The studies on warped product manifolds with extrinsic geometric point of view were intensified after the B.Y. Chen's work on CR-warped product submanifolds of Kaehler manifolds (cf. [6], [7]). Later on, similar studies were carried out in the setting of l.c.K. manifolds and nearly Kaehler manifolds (cf. [3], [11]). In the present article, we investigate a larger class of warped product submanifolds of l.c.K. manifolds, ensure their existence by constructing an example of such manifolds and   obtain some important properties of these submanifolds. With regard to the CR-warped product submanifold, a special case of generic warped product submanifolds, we  obtain  a characterization under which a CR-submanifold is reducesd to a CR-warped product submanifold.

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    REGULARITY OF WEAK SOLUTIONS TO MAGNETO-MICROPOLAR FLUID EQUATIONS
    YUAN Bao-Quan
    Acta mathematica scientia,Series B. 2010, 30 (5):  1469-1480.  DOI: 10.1016/S0252-9602(10)60139-7
    Abstract ( 867 )   RICH HTML PDF (192KB) ( 1528 )   Save

    In this article, we study the regularity of weak solutions and the blow-up criteria for smooth solutions to the magneto-micropolar fluid
    equations in R3. We obtain the classical blow-up criteria for smooth solutions (u, ω,b), i.e., Lq(0,T; Lp(R3) )for 2/q+3/p≤1 with 3<p≤∞, u C([0, T); L3(R3)) or $\nabla u\in Lq(0, T; Lp) for 3/2< p ≤∞ satisfying 2/q+3/p≤2. Moreover, our results indicate that the regularity of weak solutions is dominated by the velocity u of the fluid. In the end-point case p=∞, the blow-up criteria can be extended to more general spaces $\nabla u\in L1(0, TB0, ∞ (R3)).

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    ON THE EXPECTED DISCOUNTED PENALTY FUNCTION IN A MARKOV-DEPENDENT RISK MODEL WITH CONSTANT DIVIDEND BARRIER
    LIU Juan, XU Jian-Cheng, HU Yi-Jun
    Acta mathematica scientia,Series B. 2010, 30 (5):  1481-1491.  DOI: 10.1016/S0252-9602(10)60140-3
    Abstract ( 799 )   RICH HTML PDF (181KB) ( 1552 )   Save

    This article considers a Markov-dependent risk model with a constant dividend barrier. A system of integro-differential equations with boundary conditions satisfied by the expected discounted penalty function, with given initial environment state, is derived and solved. Explicit formulas
    for the discounted penalty function are obtained when the initial surplus is zero or when all the claim amount distributions are from rational family. In two state model, numerical illustrations with exponential claim amounts are given.

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    WEAK ORLICZ SPACE AND ITS CONVERGENCE THEOREMS
    LIU Ning, XIE Yong-Gang
    Acta mathematica scientia,Series B. 2010, 30 (5):  1492-1500.  DOI: 10.1016/S0252-9602(10)60141-5
    Abstract ( 746 )   RICH HTML PDF (165KB) ( 1506 )   Save

    In this article, a class of weak Orlicz function spaces is defined and their basic properties are discused. In particular, for the sequences in weak Orlicz space, we establish several basic convergence theorems including bounded convergence theorem, control convergence theorem and Vitali-type convergence theorem and so on. Moreover, the conditional compactness of its subsets is also discussed.

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    THE SCHUR HARMONIC CONVEXITY FOR A CLASS OF SYMMETRIC FUNCTIONS
    CHU Yu-Ming, SUN Tian-Chuan
    Acta mathematica scientia,Series B. 2010, 30 (5):  1501-1506.  DOI: 10.1016/S0252-9602(10)60142-7
    Abstract ( 726 )   RICH HTML PDF (143KB) ( 1436 )   Save

    In this article, we prove that the symmetric function
     Fn*(x, r)=∑i1+i2+…+in=r(x1i1x2i2xnin )1/r is Schur harmonic convex for x ∈R+n and r ∈ N={1, 2, 3, …}. As its applications, some analytic inequalities are established.

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    A RESULT OF SYSTEMS OF NONLINEAR COMPLEX ALGEBRAIC DIFFERENTIAL EQUATIONS
    GAO Ling-Yun
    Acta mathematica scientia,Series B. 2010, 30 (5):  1507-1513.  DOI: 10.1016/S0252-9602(10)60143-9
    Abstract ( 750 )   RICH HTML PDF (142KB) ( 1219 )   Save

    In this article, we mainly investigate the behavior of systems of complex differential equations when we add some condition to the quality of the
    solutions, and obtain an interesting result, which  extends Gackstatter and Laine's result concerning complex differential equations to the
    systems of algebraic differential equations.

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    IFS ON BOUNDARIES OF HOMOGENEOUS TREES: WQB CONDITION AND MULTIFRACTAC ANALYSIS
    LIU Hao, WEN Zhi-Xiong
    Acta mathematica scientia,Series B. 2010, 30 (5):  1514-1522.  DOI: 10.1016/S0252-9602(10)60144-0
    Abstract ( 626 )   RICH HTML PDF (171KB) ( 980 )   Save

    We study, from the point of view of the multifractal analysis, iterated function systems on totally disconnected spaces, namely, the boundaries of homogeneous trees. In particular, we study in this setting the "weak quasi-Bernoulli'' property introduced by Testud [3, 4]. After projection on R or R2, we get new examples of self-similar measures which, being WQB, obey the multifractal formalism for positive q's.

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    SOLUTIONS FOR THE QUASILINEAR ELLIPTIC PROBLEMS INVOLVING CRITICAL HARDY--SOBOLEV EXPONENTS
    KANG Dong-Sheng
    Acta mathematica scientia,Series B. 2010, 30 (5):  1529-1540.  DOI: 10.1016/S0252-9602(10)60146-4
    Abstract ( 1358 )   RICH HTML PDF (187KB) ( 1232 )   Save

    In this article,  we study  the quasilinear  elliptic problem involving critical Hardy--Sobolev exponents and Hardy  terms. By  variational methods and analytic techniques, we obtain  the existence of sign--changing solutions to the problem.

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    OPTIMAL INTERIOR PARTIAL REGULARITY FOR NONLINEAR ELLIPTIC SYSTEMS WITH DINI CONTINUOUS COEFFICIENTS
    QIU Ya-Lin, TAN Zhong
    Acta mathematica scientia,Series B. 2010, 30 (5):  1541-1554.  DOI: 10.1016/S0252-9602(10)60147-6
    Abstract ( 877 )   RICH HTML PDF (202KB) ( 1137 )   Save

    In this article, we consider nonlinear elliptic systems of divergence type with Dini continuous coefficients. The authors use a new method introduced by Duzaar and Grotowski, to prove partial regularity for weak solutions, based on a generalization of the technique of harmonic
    approximation and directly establish the optimal H\"{o}lder exponent for the derivative of a weak solution on its regular set.

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    ELLIPTIC GRADIENT ESTIMATES FOR DIFFUSION OPERATORS ON COMPLETE RIEMANNIAN MANIFOLDS
    JIAN Bin
    Acta mathematica scientia,Series B. 2010, 30 (5):  1555-1560.  DOI: 10.1016/S0252-9602(10)60148-8
    Abstract ( 761 )   RICH HTML PDF (139KB) ( 1231 )   Save

    In this note, we obtain the elliptic estimate for diffusion operator L = Δ + \nabla\phi\cdot\nabla$ on complete, noncompact Riemannian manifolds, under the curvature condition CD(K, m), which generalizes B. L. Kotschwar's work [5].  As an application, we get estimate on the heat kernel. The Bernstein-type gradient estimate for Schr\"odinger-type gradient is also derived.

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    REMARK ON CRITICAL SPEED OF TRAVELING WAVEFRONTS FOR NICHOLSON'S BLOWFLIES EQUATION WITH DIFFUSION
    WEI De, WU Jiao-Yu, MEI Ming
    Acta mathematica scientia,Series B. 2010, 30 (5):  1561-1566.  DOI: 10.1016/S0252-9602(10)60149-X
    Abstract ( 667 )   RICH HTML PDF (140KB) ( 1057 )   Save

    This note is devoted to the study on the traveling wavefronts to the Nicholson's blowflies equation with diffusion, a time-delayed reaction-diffusion equation. For the critical speed of traveling waves, we give a detailed analysis on its location and asymptotic behavior with respect to the mature age.

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    SOLUTIONS TO |A SECOND-ORDER MULTI-POINT |BOUNDARY VALUE PROBLEM |AT RESONANCE
    DU Zeng-Ji, MENG Fan-Chao
    Acta mathematica scientia,Series B. 2010, 30 (5):  1567-1576.  DOI: 10.1016/S0252-9602(10)60150-6
    Abstract ( 641 )   RICH HTML PDF (169KB) ( 1229 )   Save

    This article deals with the following second-order multi-point boundary value problem
    $$x''(t)=f(t, x(t), x'(t))+e(t), \ \ \ t\in (0,1), $$
    $$x'(0)=\sum\limits_{i=1}^{m}\alpha_{i}x'(\xi_{i}), \ \ \ x(1)=\sum\limits_{j=1}^{n}\beta_{j}x(\eta_{j}). $$
    Under the resonance conditions $\sum\limits_{i=1}^{m}\alpha_{i}=1, sum\limits_{j=1}^{n}\beta_{j}=1, \sum\limits_{j=1}^{n}\beta_{j}\eta_{j}=1$ , by applying the coincidence degree theory, some existence results of the problem are established. The emphasis here is that the dimension
    of the linear operator is two. In this paper, we extend and improve some previously known results like the ones in the references.

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    POSITIVE SOLUTIONS FOR WEAKLY COUPLED NONLINEAR ELLIPTIC SYSTEMS
    LONG Jing, YANG Jian-Fu
    Acta mathematica scientia,Series B. 2010, 30 (5):  1577-1592.  DOI: 10.1016/S0252-9602(10)60151-8

    In this article, we consider the existence of positive solutions for weakly coupled nonlinear elliptic systems
    $$\left\{ \begin{array}{ll}-\Delta u+u=(1+a(x))|u|^{p-1}u+\mu|u|^{\alpha-2}u|v|^\beta+\lambda v
    \quad & \rm{in}\ {\Bbb R}^N,\\
    -\Delta v+v=(1+b(x))|v|^{p-1}v+\mu|u|^\alpha|v|^{\beta-2}v+\lambda u
    & \rm{in} \ {\Bbb R}^N. \end{array} \right.\eqno(0.1)$$
    To find nontrivial solutions, we first investigate autonomous systems. In this case, results of bifurcation from semi-trivial solutions are obtained by the implicit function theorem. Next, the existence of positive solutions of problem (0.1) is obtained by variational methods.

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    CONTROLLABILITY FOR A PARABOLIC EQUATION WITH A NONLINEAR TERM INVOLVING THE STATE AND THE GRADIENT
    XU You-Jun, LIU Zhen-Hai
    Acta mathematica scientia,Series B. 2010, 30 (5):  1593-1604.  DOI: 10.1016/S0252-9602(10)60152-X
    Abstract ( 709 )   RICH HTML PDF (191KB) ( 1142 )   Save

    In this article, we consider the controllability of a quasi-linear heat equation involving gradient terms with Dirichlet boundary conditions in a bounded domain of RN. The results are established by using the variational methods, the related duality theory and Kakutani
    Fixed-point Theorem.

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    MODERATE DEVIATIONS FOR THE BESSEL CLOCK
    WANG Yan-Qing, JIANG Hui
    Acta mathematica scientia,Series B. 2010, 30 (5):  1605-1613.  DOI: 10.1016/S0252-9602(10)60153-1
    Abstract ( 788 )   RICH HTML PDF (178KB) ( 1033 )   Save

    By the method of change measures, the moderate deviations for the Bessel clock ∫t0ds/Xs(ν) is studied, where (Xt(ν), t ≥ 0) is a squared Bessel process with index ν>0. The rate function can be given explicitly. Furthermore, the functional moderate deviations for the Bessel clock are obtained.

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    GRADIENT ESTIMATES FOR POSITIVE SMOOTH f-HARMONIC FUNCTIONS
    CHEN Li, CHEN Wen-Yi
    Acta mathematica scientia,Series B. 2010, 30 (5):  1614-1618.  DOI: 10.1016/S0252-9602(10)60154-3
    Abstract ( 722 )   RICH HTML PDF (124KB) ( 1587 )   Save

    For Riemannian manifolds with a measure, we study the gradient estimates for positive smooth f-harmonic functions when the ∞-Bakry-Emery Ricci tensor and Ricci tensor are bounded from below, generalizing the classical ones of Yau (i.e., when f is constant).

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    BOUNDEDNESS FROM BELOW OF MULTIPLICATION OPERATORS BETWEEN α-BLOCH SPACES ON THE UNIT BALL
    ZHANG Min-Zhu
    Acta mathematica scientia,Series B. 2010, 30 (5):  1619-1630.  DOI: 10.1016/S0252-9602(10)60155-5
    Abstract ( 702 )   RICH HTML PDF (188KB) ( 1060 )   Save

    In this article,  we characterize the boundedness from below of multiplication operators between α-Bloch spaces on the unit ball.

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    ON THE EXISTENCE OF SINGULAR DIRECTIONS OF HOLOMORPHIC MAPS FROM THE UNIT DISK INTO Pn(C)
    TU Zhen-Han, ZHANG Sha-Sha
    Acta mathematica scientia,Series B. 2010, 30 (5):  1631-1639.  DOI: 10.1016/S0252-9602(10)60156-7
    Abstract ( 992 )   RICH HTML PDF (177KB) ( 900 )   Save

    This article proves the existence of Julia directions of value distribution of holomorphic mapping f from the unit disk into the n-dimensional complex projective space Pn(C) under the assumption limits_{r\rightarrow 1^{-}} T(r, f)/ log 1/1-r= +∞ for hypersurfaces in general position. A heuristic principle concerning the existence of Julia directions of holomorphic mappings from the unit disk into Pn(C) is given also.

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    CONVERGENCE AND GROWTH OF MULTIPLE DIRICHLET SERIES
    LIANG Mei-Li, GAO Zong-Sheng
    Acta mathematica scientia,Series B. 2010, 30 (5):  1640-1648.  DOI: 10.1016/S0252-9602(10)60157-9
    Abstract ( 719 )   RICH HTML PDF (162KB) ( 1215 )   Save

    This article investigates the convergence and growth of multiple Dirichlet series. The Valiron formula of Dirichlet series is extended to n-tuple Dirichlet series and an equivalence relation between the order of n-tuple Dirichlet series and its coefficients and exponents is obtained.

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    ON SOME RESULTS OF YI AND THEIR APPLICATIONS IN THE FUNCTIONAL EQUATIONS
    YANG Lian-Zhong, ZHANG Ji-Long
    Acta mathematica scientia,Series B. 2010, 30 (5):  1649-1660.  DOI: 10.1016/S0252-9602(10)60158-0
    Abstract ( 886 )   RICH HTML PDF (171KB) ( 1362 )   Save

    In this article, we  establish some uniqueness theorems  that improves some results of H. X. Yi for a family of meromorphic functions, and as applications, we give some results about the non-existence of meromorphic solutions of Fermat type functional equations.

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    DISTORTION THEOREMS FOR BLOCH MAPPINGS ON THE UNIT POLYDISC Dn
    WANG Jian-Fei, LIU Ta-Shun, TANG Xiao-Min
    Acta mathematica scientia,Series B. 2010, 30 (5):  1661-1668.  DOI: 10.1016/S0252-9602(10)60159-2
    Abstract ( 730 )   RICH HTML PDF (164KB) ( 1032 )   Save

    In this article, we establish distortion theorems for some various subfamilies of Bloch mappings defined in the unit polydisc Dn with critical points, which extend the results of Liu and Minda to higher dimensions. We obtain lower bounds of |det (f'(z))| and R det (f'(z)) for Bloch mapping f. As an application, some lower and upper bounds of Bloch constants for the subfamilies of holomorphic mappings are given.

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    THE BRANCHING CHAIN WITH DRIFT IN SPACE-TIME RANDOM ENVIRONMENT (I): MODEL, MARKOV PROPERTY, MOMENTS
    HU Di-He, HU Xiao-Yu
    Acta mathematica scientia,Series B. 2010, 30 (5):  1669-1678.  DOI: 10.1016/S0252-9602(10)60160-9
    Abstract ( 641 )   RICH HTML PDF (175KB) ( 966 )   Save

    There are three parts in this article. In Section 1, we establish the model of branching chain with drift in space-time random environment (BCDSTRE),  i.e.,  the coupling of branching chain and random walk. In Section 2,  we prove that any BCDSTRE must be a Markov chain in
    time random environment when we consider the distribution of the particles in space as a random element. In Section 3,  we calculate the first-order moments and the second-order moments of BCDSTRE.

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    CAUCHY PROBLEM FOR A |PARABOLIC EQUATION WITH NON-DIVERGENCE FORM
    ZHOU Wen-Shu, YAO Zheng-An
    Acta mathematica scientia,Series B. 2010, 30 (5):  1679-1686.  DOI: 10.1016/S0252-9602(10)60161-0
    Abstract ( 912 )   RICH HTML PDF (151KB) ( 1282 )   Save

    In this article, it is shown that there exists a unique viscosity solution of the Cauchy problem for a degenerate parabolic equation with non-divergence form.

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    SHARED VALUE IN A FINITE-DIMENSIONAL BANACH MANIFOLD
    J.M. Soriano
    Acta mathematica scientia,Series B. 2010, 30 (5):  1687-1695.  DOI: 10.1016/S0252-9602(10)60162-2
    Abstract ( 779 )   RICH HTML PDF (155KB) ( 834 )   Save

    Sufficient conditions are given to assert that two C1-mappings share only one value in a connected compact Banach manifold modelled over  Rn. The proof of the result, which is based upon continuation methods, is constructive.

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    ASYMPTOTIC BEHAVIOR FOR RANDOM WALK IN RANDOM |ENVIRONMENT WITH HOLDING TIMES
    MAO Ming-Zhi, LI Zhi-Min
    Acta mathematica scientia,Series B. 2010, 30 (5):  1696-1708.  DOI: 10.1016/S0252-9602(10)60163-4
    Abstract ( 614 )   RICH HTML PDF (197KB) ( 1121 )   Save

    In this article, we mainly discuss the asymptotic behavior for multi-dimensional continuous-time random walk in random environment with
    holding times. By constructing a renewal structure and using the point "environment viewed from the particle'', under General Kalikow's
    Condition, we show the law of large numbers (LLN) and central limit theorem (CLT) for the escape speed of random walk.

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    HYPERCYCLIC OPERATORS ON QUASI-MAZUR SPACES
    QIU Jing-Hui
    Acta mathematica scientia,Series B. 2010, 30 (5):  1709-1720.  DOI: 10.1016/S0252-9602(10)60164-6
    Abstract ( 668 )   RICH HTML PDF (191KB) ( 1057 )   Save

    Modifying the method of Ansari, we give some criteria for hypercyclicity of quasi-Mazur spaces. They can be applied to judging hypercyclicity of non-complete and non-metrizable locally convex spaces. For some special locally convex spaces, for example, K\"{o}the (LF)-sequence spaces and countable inductive limits of quasi-Mazur spaces, we investigate their hypercyclicity. As we see, bounded biorthogonal systems play an important role in the construction of Ansari. Moreover, we obtain characteristic conditions respectively for locally convex spaces having  bounded sequences with dense linear spans and for locally convex spaces  having bounded absorbing sets, which are useful in judging the existence of bounded biorthogonal systems.

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    THE REGULARITY OF THE FREE BOUNDARY FOR |STRIKE RESET OPTION
    YANG Zhou
    Acta mathematica scientia,Series B. 2010, 30 (5):  1721-1729.  DOI: 10.1016/S0252-9602(10)60165-8
    Abstract ( 653 )   RICH HTML PDF (164KB) ( 920 )   Save

    A strike reset option is an option that allows its holder to reset the strike price to the prevailing underlying asset price at a moment chosen by the holder. The pricing model of the option can be formulated as a parabolic variational inequality and the optimal reset strategy is the free boundary. The smoothness of the free boundary in some cases was  showed in our article published in JDE. We would prove its smoothness in the other case in this paper by a generalized comparison principle for the variational inequality.

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    ON THE RENEWAL RISK MODEL WITH INTEREST AND DIVIDEND
    FANG Ying, WU Rong
    Acta mathematica scientia,Series B. 2010, 30 (5):  1730-1738.  DOI: 10.1016/S0252-9602(10)60166-X
    Abstract ( 667 )   RICH HTML PDF (164KB) ( 1141 )   Save

    We consider that the reserve of an insurance company follows a renewal risk process with interest and dividend. For this risk process, we derive integral equations and exact infinite series expressions for the Gerber-Shiu discounted penalty function. Then we give lower and upper bounds for the ruin probability. Finally, we present exact expressions for the ruin probability in a special case of renewal risk processes.

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    CONFORMAL AND GENERALIZED CONCIRCULAR MAPPINGS OF EINSTEIN-WEYL MANIFOLDS
    Abdulkadir ?zdeger
    Acta mathematica scientia,Series B. 2010, 30 (5):  1739-1745.  DOI: 10.1016/S0252-9602(10)60167-1
    Abstract ( 816 )   RICH HTML PDF (139KB) ( 2104 )   Save

    In this article, after giving a necessary and sufficient condition for two Einstein-Weyl manifolds to be in conformal correspondence, we prove that any conformal mapping between such manifolds is generalized concircular if and only if the covector  field of the conformal mapping is locally a
    gradient. Using this fact we deduce that any conformal mapping between two isotropic Weyl manifolds is a generalized concircular mapping. Moreover, it is shown that a generalized concircularly flat Weyl manifold is generalized concircular to an Einstein manifold and that its scalar curvature is prolonged covariant constant.

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    THE JUMPING PHENOMENON OF THE DIMENSIONS OF COHOMOLOGY GROUPS OF TANGENT SHEAF
    YE Xuan-Ming
    Acta mathematica scientia,Series B. 2010, 30 (5):  1746-1758.  DOI: 10.1016/S0252-9602(10)60168-3
    Abstract ( 645 )   RICH HTML PDF (206KB) ( 1314 )   Save

    Let X be a compact complex manifold. Consider a small deformation πχ→ B of X, the dimensions of the cohomology groups of tangent sheaf
    H q(XtTXt) may vary under this deformation. This article  studies such phenomena by studying the obstructions to deform a class in H q(XTX) with parameter t and gets a formula for the obstructions.

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    HAZARD REGRESSION WITH PENALIZED SPLINE: THE SMOOTHING PARAMETER CHOICE AND ASYMPTOTICS
    TONG Xing-Wei, HU Tao, CUI Heng-Jian
    Acta mathematica scientia,Series B. 2010, 30 (5):  1759-1768.  DOI: 10.1016/S0252-9602(10)60169-5
    Abstract ( 756 )   RICH HTML PDF (185KB) ( 1589 )   Save

    In this article,  we  use penalized spline to estimate  the hazard function from a set of censored failure time data. A new approach to estimate the amount of smoothing is provided. Under regularity conditions we establish the consistency and the asymptotic normality of  the penalized likelihood estimators. Numerical studies and an  example are conducted to evaluate the performances of the new procedure.

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    TOWERS OF DERIVATION FOR LIE RINGS AND SOME RESULTS ON COMPLETE LIE RINGS
    LIAO Jun, ZHENG Da-Bin, LIU He-Guo
    Acta mathematica scientia,Series B. 2010, 30 (5):  1769-1775.  DOI: 10.1016/S0252-9602(10)60170-1
    Abstract ( 616 )   RICH HTML PDF (156KB) ( 937 )   Save

    The well-known tower theorem of groups (resp. Lie algebras) shows that the tower of automorphism groups (resp. derivation algebras) of a finite group (resp. a finite dimensional Lie algebra) with trivial center terminates after finitely many steps. We generalize these results for Lie rings, and present some necessary and sufficient conditions for Lie rings to be complete.

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    ON UNIQUE CONTINUATION PROPERTIES FOR THE SUB-LAPLACIAN ON |CARNOT GROUPS
    NIU Peng-Cheng, WANG Jia-Lin
    Acta mathematica scientia,Series B. 2010, 30 (5):  1776-1784.  DOI: 10.1016/S0252-9602(10)60171-3
    Abstract ( 681 )   RICH HTML PDF (164KB) ( 1233 )   Save

    In this article, authors begin with establishing representation formulas and properties for functions on Carnot groups. Then, some unique
    continuation results to solutions of sub-Laplace equations with potentials are proved.

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    HIGHER ORDER SINGULAR INTEGRAL EQUATIONS ON COMPLEX HYPERSPHERE
    CHEN Lv-Ping, ZHONG Tong-De
    Acta mathematica scientia,Series B. 2010, 30 (5):  1785-1792.  DOI: 10.1016/S0252-9602(10)60172-5
    Abstract ( 666 )   RICH HTML PDF (156KB) ( 989 )   Save

    A theory of a class of higher order singular integral under the operator (Lf)(u)=1/u1[u1 ∂f}/ ∂u1 (u)-u1 ∂f/ ∂u1 (u)+f(u)] is given. We transform the higher order singular integral to a usual Cauchy integral, extend the permutation formula of the higher order singular integral deduced by Qian and Zhong in [4] to a general case, and discuss the regularization problem of the higher order singular integral equations with Cauchy kernel and variable coefficients on complex hypersphere.

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    GLOBAL EXISTENCE AND BLOW-UP OF SOLUTIONS FOR GENERALIZED POCHHAMMER-CHREE EQUATIONS
    XU Run-Zhang, LIU YA-Cheng
    Acta mathematica scientia,Series B. 2010, 30 (5):  1793-1807.  DOI: 10.1016/S0252-9602(10)60173-7
    Abstract ( 860 )   RICH HTML PDF (200KB) ( 1383 )   Save

    In this article, we study the initial boundary value problem of generalized Pochhammer-Chree equation
    utt-uxx-uxxt-uxxtt=f(u)xx, x ∈Ω, t >0,
    u(x, 0)=u0(x), ut(x, 0)=u1(x), x ∈Ω,
    u(0, t)=u(1, t)=0, t ≥0,
    where Ω =(0, 1). First, we obtain the existence of local Wk, p solutions. Then, we prove that, if f(s) ∈ in Ck+1(R) is ondecreasing, f(0)=0 and |f(u)| ≤ C1|u0uf(s)ds + C2, u0(x), u1(x) ∈Wk, p(Ω) ∩ W0{1, p}(Ω), k ≥1, 1< p ≤∞, then for any T>0 the problem admits a unique solution u(x, t) ∈ W2, ∞ (0, T; Wk, p(Ω)∩W01, p(Ω) ). Finally, the finite time blow-up of solutions and global Wk, p solution of generalized IMBq equations are discussed.

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    QUANTUM COMPLEXITY OF THE APPROXIMATION FOR THE CLASSES Β(Wpr([0, 1]d)) AND Β(Hpr([0, 1]d))
    YE Pei-Xin, HU Xiao-Fei
    Acta mathematica scientia,Series B. 2010, 30 (5):  1808-1818.  DOI: 10.1016/S0252-9602(10)60174-9
    Abstract ( 670 )   RICH HTML PDF (195KB) ( 1006 )   Save

    We study the approximation of functions from anisotropic Sobolev classes B(Wpr}([0, 1]d)) and H\"{o}lder-Nikolskii classes B(Hpr}([0, 1]d)) in the Lq([0, 1]d) norm with q ≤ p in the quantum  model of computation. We determine the quantum query complexity of this problem up to logarithmic factors. It shows that the quantum algorithms are  significantly better  than the classical deterministic or randomized algorithms.

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    MULTI-DIMENSIONAL REFLECTED BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS AND THE COMPARISON THEOREM
    WU Zhen, XIAO Hua
    Acta mathematica scientia,Series B. 2010, 30 (5):  1819-1836.  DOI: 10.1016/S0252-9602(10)60175-0
    Abstract ( 875 )   RICH HTML PDF (216KB) ( 1739 )   Save

    In this article, we study the multi-dimensional reflected backward stochastic differential equations. The existence and uniqueness result
    of the solution for this kind of equation is proved by the fixed point argument where  every element of the solution is forced to stay above the  given stochastic process, i.e., multi-dimensional obstacle, respectively. We also give a kind of multi-dimensional comparison theorem for the reflected BSDE and then use it  as the tool to prove an existence result for the multi-dimensional reflected BSDE where the coefficient is continuous and has linear growth.

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