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    20 April 2006, Volume 26 Issue 2 Previous Issue    Next Issue
    Articles
    A NEW FAMILY OF FILTRATION s+6 IN THE STABLE HOMOTOPY GROUPS OF SPHERES
    Liu Xiugui
    Acta mathematica scientia,Series B. 2006, 26 (2):  193-201.  DOI: 10.1016/S0252-9602(06)60041-6
    Abstract ( 1189 )   RICH HTML PDF (157KB) ( 1329 )   Save

    In the year 2002, Lin detected a nontrivial family in the stable homotopy groups of spheres $\pi_{t-6}S$ which is represented by $h_ng_0\tilde{\gamma}_{3} \in {\rm Ext}_A^{6,t}(Z_p,Z_p)$ in the Adams spectral sequence, where t=2pn(p-1)+6(p2+p+1)(p-1) and p≥7 is a prime number. This article generalizes the result and proves the existence of a
    new nontrivial family of filtration s+6 in the stable homotopy groups of spheres $\pi_{t_1-s-6}S$ which is represented by $h_ng_0\tilde{\gamma}_{s+3}\in {\rm Ext}_A^{s+6,t_1}(Z_p,Z_p)$
    in the Adams spectral sequence, where n≥4, 0≤ s< p-4, t1=2pn(p-1)+2(p-1)((s+3)p2+(s+3)p+(s+3))+s.

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    ON THE BOTTLENECK CAPACITY EXPANSION PROBLEMS ON NETWORKS
    Yang Chao; Zhang Jianzhong
    Acta mathematica scientia,Series B. 2006, 26 (2):  202-208.  DOI: 10.1016/S0252-9602(06)60042-8
    Abstract ( 1160 )   RICH HTML PDF (142KB) ( 1288 )   Save

    This article considers a class of bottleneck capacity expansion problems.
    Such problems aim to enhance bottleneck capacity to a certain level with minimum cost. Given a network $G(V,A,\overline{C})$ consisting of
    a set of nodes V={v1,v2,... ,vn}, a set of arcs $A \subseteq \{(v_i,v_j)\ |\ i=1,2,\cdots ,n; ~j=1,2,\cdots ,n \}$ and a capacity vector $\overline{C}$. The component $\overline{c}_{ij}$ of $\overline{C}$ is the capacity of arc $(v_i,v_j)$. Define the capacity of a subset $A'$ of $A$ as the minimum capacity of the arcs in $A$, the capacity of a family ${\cal F}$ of subsets of $A$ is the maximum capacity of its members. There are two types of expanding models. In the arc-expanding model, the unit cost to increase the capacity of arc $(v_i,v_j)$ is $w_{ij}$. In the node-expanding model, it is
    assumed that the capacities of all arcs $(v_i,v_j)$ which start at the same node vi should be increased by the same amount and that the unit cost to make such expansion is wi. This article considers three kinds of bottleneck capacity expansion problems (path, spanning arborescence and maximum flow) in both expanding models. For each kind of expansion problems,
    this article discusses the characteristics of the problems and presents several results on the complexity of the problems.

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    ON CRITICAL SINGULAR QUASILINEAR ELLIPTIC PROBLEM WHEN n=p
    Yao Yangxin; Shen Yaotian
    Acta mathematica scientia,Series B. 2006, 26 (2):  209-219.  DOI: 10.1016/S0252-9602(06)60043-X
    Abstract ( 1069 )   RICH HTML PDF (168KB) ( 1382 )   Save

    This article deals with the problem
    $$ -\Lap_p
    u=\lambda{|u|^{p-2}u\over\xlnxRt}+f(x,u),\quad x\in\Omega;\qquad
    u=0,x\in\partial\Om, $$
    where $n = p.$ The authors prove that a Hardy inequality and the constant $ (\pp)^p $ is optimal. They also prove the existence of a nontrivial solution of the above mentioned problem by using the Mountain Pass Lemma.

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    EXISTENCE OF SOLUTION FOR A BOUNDARY VALUE PROBLEM OF FRACTIONAL ORDER
    Zhang Shuqin
    Acta mathematica scientia,Series B. 2006, 26 (2):  220-228.  DOI: 10.1016/S0252-9602(06)60044-1
    Abstract ( 1274 )   RICH HTML PDF (144KB) ( 4864 )   Save

    This article considers the existence of solution for a boundary value problem of fractional order, involving Caputo's derivative
    $$
    \left\{
    \begin {array}{l}
    _0^{C}D_t^\delta u(t) =g(t,u(t)),\quad 0u(0)=\alpha\neq 0,\quad u(1)=\beta\neq 0.
    \end{array}
    \right.
    $$

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    EXISTENCE AND ASYMPTOTIC BEHAVIOR OF THE SOLUTIONS FOR A NONLINEAR ELLIPTIC EQUATION ARISING IN ASTROPHYSICS
    Tang Zhongwei
    Acta mathematica scientia,Series B. 2006, 26 (2):  229-245.  DOI: 10.1016/S0252-9602(06)60045-3
    Abstract ( 1217 )   RICH HTML PDF (215KB) ( 1096 )   Save

    The author first analyzes the existence of ground state solutions and cylindrically symmetric solutions and then the asymptotic behavior of the ground state solution of the equation
    -△u=\phi(r) up-1, u>0, in RN, u ∈D1,2(RN),

    where N≥3, x=(x',z) ∈RK×RN-K,2≤ K≤ N,r=|x'|. It is proved that for 2(N-s)/(N-2)*=2N/(N-2), 0*, the above equation does not have a ground state solution but a cylindrically symmetric solution, and when p close to 2*, the ground state solutions are not cylindrically
    symmetric. On the other hand, it is proved that as p close to 2*, the ground state solution up has a unique maximum point xp=(x'p,zp) and as p \to 2*,|x'p|→ r0 which attains the maximum of $\phi$ on RN. The asymptotic behavior of ground state solution up is also given, which also deduces that the ground state solution is not cylindrically symmetric as p goes to 2*.

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    ASYMPTOTIC BEHAVIOR FOR COMMUTATIVE SEMIGROUPS OF ALMOST ASYMPTOTICALLY NONEXPANSIVE TYPE MAPPINGS
    Zeng Luchuan
    Acta mathematica scientia,Series B. 2006, 26 (2):  246-254.  DOI: 10.1016/S0252-9602(06)60046-5
    Abstract ( 1037 )   RICH HTML PDF (142KB) ( 1461 )   Save

    This article introduces the concept of commutative semigroups of almost asymptotically nonexpansive-type mappings in a Banach space X which has the Opial property and whose norm is UKK, and establishes the weak
    convergence theorems for almost-orbits of this class of commutative semigroups. The author improves, extends and develops some recent and earlier results.

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    THE FIRST BOUNDARY VALUE PROBLEM FOR STRONGLY DEGENERATE QUASILINEAR PARABOLIC EQUATIONS IN ANISOTROPIC SOBOLEV SPACES
    Zhao Yanyan; Chen Zuchi
    Acta mathematica scientia,Series B. 2006, 26 (2):  255-264.  DOI: 10.1016/S0252-9602(06)60047-7
    Abstract ( 1164 )   RICH HTML PDF (144KB) ( 910 )   Save

    This article concerns the existence of weak solutions of the first boundary value problem for a kind of strongly degenerate quasilinear parabolic equation in the anisotropic Sobolev Space. With the theory of anisotropic
    Sobolev spaces an existence result is proved.

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    A POLYNOMIAL PREDICTOR-CORRECTOR INTERIOR-POINT ALGORITHM FOR CONVEX QUADRATIC PROGRAMMING
    Yu Qian; Huang Chongchao; Jiang Yan
    Acta mathematica scientia,Series B. 2006, 26 (2):  265-270.  DOI: 10.1016/S0252-9602(06)60048-9
    Abstract ( 1049 )   RICH HTML PDF (135KB) ( 1860 )   Save

    This article presents a polynomial predictor-corrector interior-point algorithm for convex quadratic programming based on a modified predictor-corrector interior-point algorithm. In this algorithm, there is only one corrector step after each predictor step, where Step 2 is a predictor step and Step 4 is a corrector step in the algorithm. In the algorithm, the predictor step decreases the dual gap as much as possible in a wider neighborhood of the central path and the corrector step draws iteration points back to a narrower neighborhood and make a reduction for the dual gap. It is shown that the algorithm has ${\rm O}(\sqrt n L)$ iteration complexity which is the best result for convex quadratic programming so far.

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    ENDPOINT ESTIMATE FOR MAXIMAL COMMUTATORS WITH NON-DOUBLING MEASUES
    Hu Guoen; Meng Yan; Yang Dachun
    Acta mathematica scientia,Series B. 2006, 26 (2):  271-280.  DOI: 10.1016/S0252-9602(06)60049-0
    Abstract ( 1111 )   RICH HTML PDF (157KB) ( 1090 )   Save

    The authors establish the weak type endpoint estimate for the maximal commutators generated by Calderon-Zygmund singular integrals and Orlicz type functions with non-doubling measures.

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    ASYMPTOTICALLY ISOMETRIC COPIES OF lp (1≤ p<∞) AND c0 IN BANACH SPACES
    Chen Dongyang
    Acta mathematica scientia,Series B. 2006, 26 (2):  281-290.  DOI: 10.1016/S0252-9602(06)60050-7
    Abstract ( 1040 )   RICH HTML PDF (167KB) ( 1465 )   Save

    Let X be a Banach space. If there exists a quotient space of X which is asymptotically isometric to l1, then X contains complemented asymptotically isometric copies of l1. Every infinite dimensional closed subspace of l1 contains a complemented subspace of l1 which is asymptotically isometric
    to l1. Let X be a separable Banach space such that X* contains asymptotically isometric copies of lp (1q (\frac{1}{p}+\frac{1}{q}=1). Complemented asymptotically isometric copies of c0 in K(X,Y) and W(X,Y) are discussed. Let X be a Gelfand-Phillips space. If X contains asymptotically isometric copies of c0, it has to contain complemented asymptotically isometric copies of c0.

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    GLOBAL STABILITY OF AN SIRS EPIDEMIC MODEL WITH DELAYS
    Zhen Jin; Ma Zhien; Han Maoan
    Acta mathematica scientia,Series B. 2006, 26 (2):  291-306.  DOI: 10.1016/S0252-9602(06)60051-9
    Abstract ( 1303 )   RICH HTML PDF (186KB) ( 2875 )   Save

    In this article, an SIRS epidemic model spread by vectors (mosquitoes) which have an incubation time to become infectious is formulated. It is shown that a disease-free equilibrium point is globally stable if no endemic equilibrium point exists. Further, the endemic equilibrium point (if it exists) is globally stable
    with a respect ``weak delay". Some known results are generalized.

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    PROJECTIVELY FLAT FINSLER METRICS WITH ALMOST ISOTROPIC S-CURVATURE
    Cheng Xinyue; Shen Zhongmin
    Acta mathematica scientia,Series B. 2006, 26 (2):  307-313.  DOI: 10.1016/S0252-9602(06)60052-0
    Abstract ( 930 )   RICH HTML PDF (127KB) ( 2261 )   Save

    This article characterizes projectively flat Finsler metrics with almost isotropic S-curvature.

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    CIRCULAR CHROMATIC NUMBER AND MYCIELSKI GRAPHS
    Liu Hongmei
    Acta mathematica scientia,Series B. 2006, 26 (2):  314-320.  DOI: 10.1016/S0252-9602(06)60053-2
    Abstract ( 965 )   RICH HTML PDF (138KB) ( 1529 )   Save

    For a general graph G, M(G) denotes its Mycielski graph. This article gives a number of new sufficient conditions for G to have the circular chromatic
    number $\chi_c(M(G))$ equals to the chromatic number $\chi(M(G))$,
    which have improved some best sufficient conditions published up to date.

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    ON THE RUIN FUNCTIONS FOR A CORRELATED AGGREGATE CLAIMS MODEL WITH POISSON AND ERLANG RISK PROCESSES
    Liu Yan; Yang Wenquan; Hu Yijun
    Acta mathematica scientia,Series B. 2006, 26 (2):  321-330.  DOI: 10.1016/S0252-9602(06)60054-4
    Abstract ( 1164 )   RICH HTML PDF (140KB) ( 1418 )   Save

    This article considers a risk model as in Yuen et al. (2002). Under this model the two claim number processes are correlated. Claim occurrence of both
    classes relate to Poisson and Erlang processes. The formulae is derived for the distribution of the surplus immediately before ruin, for the distribution of the surplus immediately after ruin and the joint distribution of the surplus immediately before and after ruin. The asymptotic property of these ruin functions is also investigated.

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    SAMPLING INSPECTION OF RELIABILITY IN (LOG)NORMAL CASE#br# WITH TYPE I CENSORING
    Wu Qiguang; Lu Jianhua
    Acta mathematica scientia,Series B. 2006, 26 (2):  331-343.  DOI: 10.1016/S0252-9602(06)60055-6
    Abstract ( 1136 )   RICH HTML PDF (170KB) ( 1505 )   Save

    This article proposes a statistical method for working out reliability sampling plans under Type I censored sample for items whose failure times have either normal or lognormal distributions. The quality statistic is a method of moments estimator of a monotonous function of the unreliability. An approach of choosing a truncation time is recommended. The sample size and acceptability constant are approximately determined by using the Cornish-Fisher expansion for quantiles of distribution. Simulation results show that the method given in this article is feasible.

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    KERNEL IDEALS AND CONGRUENCES ON MS-ALGEBRAS
    Luo Congwen; Zeng Yanlu
    Acta mathematica scientia,Series B. 2006, 26 (2):  344-348.  DOI: 10.1016/S0252-9602(06)60056-8
    Abstract ( 1046 )   RICH HTML PDF (111KB) ( 1618 )   Save

    In this article, the authors describe the largest congruence induced by a kernel ideal of an MS-algebra and characterize those MS-algebras on which all the congruences are in a one-to-one correspondence with the kernel ideals.

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    ON STATIONARY HYPERSURFACES IN EUCLIDEAN SPACES
    Zhao Peibiao; Yang Xiaoping
    Acta mathematica scientia,Series B. 2006, 26 (2):  349-357.  DOI: 10.1016/S0252-9602(06)60057-X
    Abstract ( 1138 )   RICH HTML PDF (155KB) ( 1365 )   Save

    Some techniques in the Geometric Measure Theory are used to study the hypersurfaces in Euclidean spaces and some fundamental properties with this subject are discussed in this article.

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    ABSOLUTE CONTINUITIES OF EXIT MEASURES AND TOTAL WEIGHTED OCCUPATION TIME MEASURES FOR SUPER-α-STABLE PROCESSES
    Zhang Jing; Ren Yanxia
    Acta mathematica scientia,Series B. 2006, 26 (2):  358-370.  DOI: 10.1016/S0252-9602(06)60058-1
    Abstract ( 1222 )   RICH HTML PDF (174KB) ( 897 )   Save

    Suppose X is a super-α-stable process in Rd, (0<α<2), whose branching rate function is dt, and branching mechanism is of the form ψ(z)=z1+β
    (0<β≤1). Let Xτ and Yτ denote the exit measure and the total weighted occupation time measure of X in a bounded smooth domain D, respectively. The absolute continuities of Xτ and Yτ are discussed.

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    ON THE LASOTA-WAZEWSKA MODEL WITH PIECEWISE CONSTANT ARGUMENT
    Feng Qiuxiang; Yuan Rong
    Acta mathematica scientia,Series B. 2006, 26 (2):  371-378.  DOI: 10.1016/S0252-9602(06)60059-3
    Abstract ( 1091 )   RICH HTML PDF (141KB) ( 2125 )   Save

    In this article, a delay differential equation with piecewise constant argument is considered; the existence and global attractivity condition of almost periodic solution and quasi-periodic solution are obtained.

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    WEAK UNCORRELATEDNESS OF RANDOM VARIABLES
    Sofiya Ostrovska
    Acta mathematica scientia,Series B. 2006, 26 (2):  379-384.  DOI: 10.1016/S0252-9602(06)60060-X
    Abstract ( 1091 )   RICH HTML PDF (115KB) ( 1012 )   Save

    New measures of independence for n random variables, based on their moments, are studied. A scale of degrees of independence for random variables which starts with uncorrelatedness (for n=2) and finishes at independence is constructed. The scale provides a countable linearly ordered set of measures of independence.

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