k－Bounded Space On－line装箱中AFB_k算法的界

Ｊ．Ｃｓｉｒｉｋ与Ｄ．Ｓ．Ｊｏｈｎｓｏｎ针对带ｋ－箱限制的在线装箱问题提出了四种装入和关闭法则，并利用这些法则给出了四种相应的算法．其中ＢＢＦｋ，ＮｋＦ和ＡＢＦｋ算法的紧界在文［１－３］中分别进行了很好的研究．但对算法ＡＦＢｋ来讲，其紧界仍是一个公开问题．本文给出了ＡＦＢｋ算法性能比的一个上界，即．同时，本文提出了一个新的关闭法则，对ＡＦＢｋ算法进行了修改，使修改后的算法ＡＦＢｋ的性能比不超过１．７（ｋ３）     

带有延迟时间下界的k-(n1,1,…,1)-排序问题的拟多项式时间算法

讨论Wikum的关于带有延迟时间下界的k-(n1,1,…,1)-链形结构排序问题的拟多项式时间算法,其中当n1=2的情况已由Yin等人(1999)解决,这里主要以n1=3的情形为例作更加细致的分析,然后给出较Yin等人(1999)的算法更加有效的拟多项式时间算法.为了保持文章的连续性,也将列出Yin等人(1999)的n1=2的算法加以比较.     

几何分布时间序贯检验的贝叶斯推断

设有统计模型｛ｘ,Ｂｘ,Ｐθ｝,θ∈（０,１）,其中Ｐθ为几何分布：Ｐθ（Ｘ＝ｋ）＝（１－θ）θ＾ｋ－１ｋ＝１,２,…。考虑检验问题：θ＝θｏ ｖｓ． θ＝θ１（０〈θ０〈θ１〈１）本文对一种依次试验的时间序贯样本,给出了上述检验问题的贝叶斯停止判决法则,其中损失函数为试验费用和误判损失之和,贝叶斯停止判决法则由后验概率的两组界（上界和下界）所给出。     

关于带有完全对称函数的广义数值域

本文给出了矩阵Ａ的带有完全对称函数Ｃｋ的ｍ－数值域在复平面上为线段的充分必要条件．     

关于最大权k－子集分拆问题

对给定规模为ｎ的集合Ｓ，其每一个规模至多为ｋ的子集对应一个权．本文研究如何将Ｓ分为　个互不相交的规模至多为ｋ的子集且满足权和最大的问题．我们证明了该问题当ｋ＝２时是多项式时间可解的；当ｋ≥３时为ＮＰ－完全的；同时给出了一个Ｏ（ｎ￣（ｋ＋１））时间的启发式算法，所得到的解与最优解之比不小于１／ｋ．     

关于一类Ornstein—Uhlenbeck型马氏过程Range的维数

本文我们考虑一类Ｏｒｎｓｔｅｉｎ－Ｕｈｌｅｎｂｅｃｋ型马氏过程Ｒａｎｇｅ的分形性质，给出了它们的Ｈａｕｓｄｏｒｆｆ维数的上界和下界，此外在文末我们对这类过程的水平集的维数给了估计。     

多目标规划αk-较多有效解类的若干性质

在［１］中,作者提出多目标规划的较多有效解和较多最优解概念,并研究了它们的基本性质．文［３］则讨论了ｋ－较多最优解的若干性质．文［４］利用较多序类进一步引进多目标规划问题的αｋ－较多有效解,并证明了这类解的最优性必要条件．本文再给出多目标规划问题的αｋ－较多最优解的概念,并讨论了多目标规划αｋ－较多有效解和αｋ－较多最优解的若干重要性质．     

延迟控制休假的M／M／1排队系统

本文研究带有延迟休假的 Ｍ／Ｍ／１排队系统,服务员在空闲了一段时间（称做延迟时间）后才正式开始休假,每次休假的时间长度有指数分布．若一次休假结束时系统中的顾客数目低于某一水平Ｋ,则服务员开始另一次休假;否则转为投入服务,这时系统开始一个新的忙期。对于延迟时间有指数分布和是确定的情形分别求得系统的稳态分布的精确表示及某些性能指标．文章还讨论了系统优化问题,给出使得单位时间平均总成本最小的Ｋ值．证明在泊松到达的情形最优延迟时间是０（无延迟）或无穷（无休假）     

数学问题解答

数学问题解答１９９８年５月号问题解答（解答由问题提供人给出）１１３１试证：一元多项式Ｐ（ｘ）＝ｘｋ－ｘｋ－１－１的复根ｚ＝ｒｅｉθ一定满足ｒ２ｋ－２ｒ２ｋ－１ｃｏｓθ＋ｒ２ｋ－２－１＝０．证明我们有｜Ｐ（ｚ）｜｜ｚｋ－ｚｋ－１｜－１＝ｒｋ－１｜ｚ－...     

关于k－复盖图的几个条件

设Ｇ是一个图，ｋ为正整数．图Ｇ的一个ｋ－正则支撑子图Ｆ称做图Ｇ的一个ｋ－因子．若图Ｇ的每一条边ｅ都属于Ｇ的一个ｋ－因子，则称Ｇ是一个ｋ－复盖图．本文给出了一个图Ｇ是ｋ－复盖图的几个充分条件．     

Qualitative Analysis of Bifurcating Solutions in the Lengyel-Epstein Model

One of the most fundamental problems in theoretical biology is to explain the mechanisms by which patterns and forms are created in the＇living world. In his seminal paper ＂The Chemical Basis of Morphogenesis＂, Turing showed that a system of coupled reaction-diffusion equations can be used to describe patterns and forms in biological systems. However, the first experimental evidence to the Turing patterns was observed by De Kepper and her associates（1990） on the CIMA reaction in an open unstirred reactor, almost 40 years after Turing＇s prediction. Lengyel and Epstein characterized this famous experiment using a system of reaction-diffusion equations. The Lengyel-Epstein model is in the form as follows     

A REPRESENTATION FORMULA RELATED TO SCHR(O)DINGER OPERATORS

Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.     

On a class of self-similar processes with stationary increments in higher order Wiener chaoses

We study a class of self-similar processes with stationary increments belonging to higher order Wiener chaoses which are similar to Hermite processes. We obtain an almost sure wavelet-like expansion of these processes. This allows us to compute the pointwise and local Hölder regularity of sample paths and to analyse their behaviour at infinity. We also provide some results on the Hausdorff dimension of the range and graphs of multidimensional anisotropic self-similar processes with stationary increments defined by multiple Wiener–Itô integrals.     

(0,1 ;0)-INTERPOLATION ON INFINITE INTERVAL (-∞, +∞)

In this paper, we study the explicit representation and convergence of (0, 1; 0)-interpolation on infinite interval, which means to determine a polynomial of degree ≤ 3n - 2 when the function values are prescribed at two set of points namely the zeros of Hn(x) and H′n(x) and the first derivatives at the zeros of H′n(x).     

On a class of Riemann surfaces

It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary.     

CONTENTS OF VOLUME 30

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Instructions for contributions

正Applied Mathematics-A Journal of Chinese Universities,Series B(Appl.Math.J.Chinese Univ.,Ser.B)is a comprehensive applied mathematics journal jointly sponsored by Zhejiang University,China Society for Industrial and Applied Mathematics,and Springer-Verlag.It is a quarterly journal with     

Journal of Mathematical Research with Applications Guide for Authors

正Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.     

Staircase transportation problems with superadditive rewards and cumulative capacities

A cumulative-capacitated transportation problem is studied. The supply nodes and demand nodes are each chains. Shipments from a supply node to a demand node are possible only if the pair lies in a sublattice, or equivalently, in a staircase disjoint union of rectangles, of the product of the two chains. There are (lattice) superadditive upper bounds on the cumulative flows in all leading subrectangles of each rectangle. It is shown that there is a greatest cumulative flow formed by the natural generalization of the South-West Corner Rule that respects cumulative-flow capacities; it has maximum reward when the rewards are (lattice) superadditive; it is integer if the supplies, demands and capacities are integer; and it can be calculated myopically in linear time. The result is specialized to earlier work of Hoeffding (1940), Fréchet (1951), Lorentz (1953), Hoffman (1963) and Barnes and Hoffman (1985). Applications are given to extreme constrained bivariate distributions, optimal distribution with limited one-way product substitution and, generalizing results of Derman and Klein (1958), optimal sales with age-dependent rewards and capacities.To our friend, Philip Wolfe, with admiration and affection, on the occasion of his 65th birthday.Research was supported respectively by the IBM T.J. Watson and IBM Almaden Research Centers and is a minor revision of the IBM Research Report [6].