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Table of Content

    13 July 2004, Volume 24 Issue 1 Previous Issue    Next Issue
    Articles
    MORE ABOUT MELLIN TRANSFORM IN WEAK FUNCTIONS AND M¨UNTS FORMULA
    Ding-Jia-Qi, LUO Pei-Zhu
    Acta mathematica scientia,Series B. 2004, 24 (1):  1-8. 
    Abstract ( 575 )   RICH HTML PDF (102KB) ( 798 )   Save

    This paper is a further continuation of the paper [1]. In the present paper
    Mellin transform and M¨unts formula of weak functions in complex domain will be treated.

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    ON QUADRATURE FORMULAE FOR SINGULAR |INTEGRALS OF ARBITRARY ORDER
    DU Jin-Yuan
    Acta mathematica scientia,Series B. 2004, 24 (1):  9-27. 
    Abstract ( 543 )   RICH HTML PDF (182KB) ( 1168 )   Save

    t Some quadrature formulae for the numerical evaluation of singular integrals
    of arbitrary order are established and both the estimate of remainder and the convergence
    of each quadrature formula derived here are also given.

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    LOCAL MEDIAN ESTIMATION OF VARIANCE FUNCTION
    YANG Ying, W. C. Ip, Y. K. Kwan
    Acta mathematica scientia,Series B. 2004, 24 (1):  28-38. 
    Abstract ( 565 )   RICH HTML PDF (141KB) ( 958 )   Save

    This paper considers local median estimation in fixed design regression prob-
    lems. The proposed method is employed to estimate the median function and the variance
    function of a heteroscedastic regression model. Strong convergence rates of the proposed
    estimators are obtained. Simulation results are given to show the performance of the
    proposed methods.

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    HYPERSURFACES IN SPACE FORMS WITH SCALAR CURVATURE CONDITIONS
    XU Sen-Lin, ZHANG Yun-Chao
    Acta mathematica scientia,Series B. 2004, 24 (1):  39-44. 
    Abstract ( 533 )   RICH HTML PDF (104KB) ( 982 )   Save

    Let $\ f:M^n$ $\hookrightarrow $ $S^{n+1}$
    $\subset $ $R^{n+2}$ be an $n$-dimensional complete oriented
    Riemannian manifold minimally immersed in an $(n+1)$-dimensional 
    unit sphere $S^{n+1}$. Denote by $S^{n+1}_+$ the upper closed
    hemisphere.
    If $f(M^n)\subseteq S_{+}^{n+1}$, then under some curvature
    conditions the authors can get that the isometric immersion is a totally
    embedding. They also generalize a theorem of Li Hai Zhong
     on hypersurface of space form with costant scalar curvature.

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    A RECOGNITION OF SIMPLE GROUPS PSL(3, q) BY THEIR ELEMENT ORDERS
    M. R. Darafsheh;A. R. Moghaddamfar A.R. Zokay
    Acta mathematica scientia,Series B. 2004, 24 (1):  45-51. 
    Abstract ( 604 )   RICH HTML PDF (127KB) ( 2135 )   Save

    For any group G, denote by e(G) the set of orders of elements in G. Given
    a finite group G, let h(e(G)) be the number of isomorphism classes of finite groups with
    the same set e(G) of element orders. A group G is called k-recognizable if h(e(G)) =
    k < 1, otherwise G is called non-recognizable. Also a 1-recognizable group is called a
    recognizable (or characterizable) group. In this paper the authors show that the simple
    groups PSL(3, q), where 3 < q  ±2 (mod 5) and (6, (q − 1)/2) = 1, are recognizable.

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    ON THE GROWTH OF SOLUTIONS OF A CLASS OF HIGHER ORDER DIFFERENTIAL EQUATIONS
    CHEN Zong-Xuan, SUN Guang-Gao
    Acta mathematica scientia,Series B. 2004, 24 (1):  52-60. 
    Abstract ( 605 )   RICH HTML PDF (141KB) ( 1623 )   Save

    In this paper, authors investigate the order of growth and the hyper order of
    solutions of a class of the higher order linear differential equation, and improve results of
    M. Ozawa[6], G. Gundersen[7] and J.K. Langley[8], Li Chun-hong[11]

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    BOOTSTRAP WAVELET IN THE NONPARAMETRIC REGRESSION MODEL WITH WEAKLY DEPENDENT PROCESSES
    LIN Lu, ZHANG Run-Chu
    Acta mathematica scientia,Series B. 2004, 24 (1):  61-70. 
    Abstract ( 531 )   RICH HTML PDF (131KB) ( 891 )   Save

    This paper introduces a method of bootstrap wavelet estimation in a non-
    parametric regression model with weakly dependent processes for both fixed and random
    designs. The asymptotic bounds for the bias and variance of the bootstrap wavelet estima-
    tors are given in the fixed design model. The conditional normality for a modified version
    of the bootstrap wavelet estimators is obtained in the fixed model. The consistency for
    the bootstrap wavelet estimator is also proved in the random design model. These results
    show that the bootstrap wavelet method is valid for the model with weakly dependent
    processes.

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    LOCAL REGULARITY RESULT FOR SOLUTIONS OF OBSTACLE PROBLEMS
    GAO Gong-E, TIAN Hui-Yang
    Acta mathematica scientia,Series B. 2004, 24 (1):  71-74. 
    Abstract ( 591 )   RICH HTML PDF (97KB) ( 1243 )   Save

    This paper gives the local regularity result for solutions
    to obstacle problems of $A$-harmonic equation $\mbox {div} A(x,
    \bigtriangledown u(x))=0$, $|A(x, \xi )|\approx |\xi|^{p-1}$, when
    $1<p<n$ and the obstacle function $\psi \geq 0$.

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    ON THE BOREL DIRECTION OF K-QUASIMEROMORPHIC MAPPINGS
    YANG Yan, LIU Ming-Sheng
    Acta mathematica scientia,Series B. 2004, 24 (1):  75-82. 
    Abstract ( 567 )   RICH HTML PDF (120KB) ( 1022 )   Save

    For the K-quasimeromorphic mappings, a precise fundamental inequality for
    the angular domain is established. From this, the Borel direction of the K-quasimeromorphic
    mappings of zero order is derived.

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    MEROMORPHIC FUNCTIONS THAT SHARE TWO SETS, II
    YI Hong-Xun, LV Wei-Ran
    Acta mathematica scientia,Series B. 2004, 24 (1):  83-90. 
    Abstract ( 646 )   RICH HTML PDF (110KB) ( 1176 )   Save

    his paper deals with the problem of uniqueness
    of meromorphic functions,  and gets the following result:
    There exists a set $S$ with $13$ elements such that any two
    non-constant meromorphic functions
    $f$ and $g$ satisfying $\overline{E}(S,f)=\overline{E}(S,g)$  and
    $\overline{E}(\{\infty\},f)=\overline{E}(\{\infty\},g)$
    must be identical. This is  the best result
    on this question until now.

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    FORWARD-BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS WITH STOPPING TIME
    TUN Zhen
    Acta mathematica scientia,Series B. 2004, 24 (1):  91-99. 
    Abstract ( 635 )   RICH HTML PDF (126KB) ( 1672 )   Save

    The existence and uniqueness results of fully coupled forward-backward sto-
    chastic differential equations with stopping time (unbounded) is obtained. One kind of
    comparison theorem for this kind of equations is also proved.
     

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    BILINEAR FORMS AND LINEAR CODES
    GAO Ying
    Acta mathematica scientia,Series B. 2004, 24 (1):  100-106. 
    Abstract ( 521 )   RICH HTML PDF (110KB) ( 910 )   Save

    Abraham Lempel et al[1] made a connection between linear codes and systems
    of bilinear forms over finite fields. In this correspondence, a new simple proof of a theorem
    in [1] is presented; in addition, the encoding process and the decoding procedure of RS codes
    are simplified via circulant matrices. Finally, the results show that the correspondence
    between bilinear forms and linear codes is not unique.

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    CONFIDENCE REGIONS IN TERMS OF STATISTICAL CURVATURE FOR AR(q) NONLINEAR REGRESSION MODELS 1
    LIU Ying-An, HUI Bo-Cheng
    Acta mathematica scientia,Series B. 2004, 24 (1):  107-117. 
    Abstract ( 573 )   RICH HTML PDF (141KB) ( 857 )   Save

    This paper constructs a set of confidence regions of parameters in terms of
    statistical curvatures for AR(q) nonlinear regression models. The geometric frameworks
    are proposed for the model. Then several confidence regions for parameters and parameter
    subsets in terms of statistical curvatures are given based on the likelihood ratio statistics
    and score statistics. Several previous results, such as [1] and [2] are extended to AR(q)
    nonlinear regression models.

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    NON-NEWTON FILTRATION EQUATION WITH SPECIAL MEDIUM VOID
    TAN Zhong
    Acta mathematica scientia,Series B. 2004, 24 (1):  118-128. 
    Abstract ( 553 )   RICH HTML PDF (142KB) ( 1135 )   Save

    This paper  considers the existence and asymptotic
    estimates of global solutions and finite time blowup of
    local solution of non-Newton filtration equation with special
     medium void of the following form:
    $$ \left\{
    \begin{array}{ll}
    \displaystyle \frac{u_t}{|x|^2}-\bigtriangleup_p u=u^q, &  (x,t)\in\Omega\times (0,T),\\[2mm]
    u(x,t)=0, & (x,t)\in\partial\Omega\times (0,T),\\
    u(x,0)=u_0(x), & u_0(x)\geq 0, u_0(x)\not\equiv 0,
    \end{array}\right.$$
    where $\bigtriangleup_pu={\rm div}
    \left(|\bigtriangledown u|^{p-2}\bigtriangledown u\right)$,
    $\Omega$ is a smooth bounded domain in $R^N(N\geq 3$), $0\in\Omega$,
    $2<p<N$, $p-1<q<\frac{Np}{N-p}-1$. The result of asymptotic estimate of
    global solution depends on the best constant in Hardy inequality.

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    A FINITE VOLUME ELEMENT METHOD FOR THERMAL CONVECTION PROBLEMS
    RUI Hong-Xin
    Acta mathematica scientia,Series B. 2004, 24 (1):  129-138. 
    Abstract ( 574 )   RICH HTML PDF (179KB) ( 1099 )   Save

    Consider the finite volume element method for the thermal convection problem
    with the infinite Prandtl number. The author uses a conforming piecewise linear function
    on a fine triangulation for velocity and temperature, and a piecewise constant function on
    a coarse triangulation for pressure. For general triangulation the optimal order H1 norm
    error estimates are given.

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    A CLASS OF STATIONARY MODELS OF SINGULAR STOCHASTIC CONTROL
    LIU Kun-Hui, QIN Meng-Da, LIU Chuan-Lai
    Acta mathematica scientia,Series B. 2004, 24 (1):  139-150. 
    Abstract ( 588 )   RICH HTML PDF (149KB) ( 983 )   Save

    A class of stationary models of singular stochastic control has been studied,
    in which the state is extended to solution of a class of S.D.E. from Wiener process. The
    existence of optimal control has been proved in all cases under some weaker conditions,
    and the structure of optimal control may be characterized.

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    PERIODIC SOLUTIONS FOR GENERALIZED PREDATOR-PREY SYSTEMS WITH TIME DELAY AND DIFFUSION
    LI Bi-Wen
    Acta mathematica scientia,Series B. 2004, 24 (1):  151-160. 
    Abstract ( 678 )   RICH HTML PDF (131KB) ( 818 )   Save

    A set of easily verifiable sufficient
    conditions are derived for the existence of positive
    periodic solutions for delayed generalized predator-prey dispersion system
    $$
    \begin{array}{l}
    x'_{1}(t)=x_1(t)g_1(t,x_1(t))-a_1(t)y(t)p_1(x_1(t))+ D_1(t)(x_2(t)-x_1(t)),\\
    x'_{2}(t)=x_2(t)g_2(t,x_2(t))-a_2(t)y(t)p_2(x_2(t))+ D_2(t)(x_1(t)-x_2(t)),\\
    y'(t)=y(t)\left[-h(t,y(t))+b_1(t)p_1(x_1(t-\tau_1))+ b_2(t)p_2(x_2(t-\tau_2))
    \right],
    \end{array}
    $$
    where $a_i(t),b_i(t)$ and $D_i(t)(i=1,2)$
    are positive continuous $T$-periodic functions,
    $g_i(t,x_i)$
    $(i=1,2)$ and $h(t,y)$ are continuous and
    $T$-periodic with respect to $t$ and $h(t,y)>0$
    for $y>0,t,y\in R,p_i(x)(i=1,2)$ are continuous and
    monotonously increasing functions, and
    $p_i(x_i)>0$ for $x_i>0$.

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