一类扩展线性规划问题的推广

研究文［１］的扩展线性规划问题的更一般的情形：ｍｉｎｚ＝∑ｎｊ＝１ｃｊ｜ｘｊ｜，ｓ．ｔＡｘ＝ｂ，ｘｊ≥０，ｊ∈Ｉ｛１，２，…，ｎ｝。给出其不扩展单纯形表的单纯形算法。     

排序问题的线性规划松弛方法

本文研究排序问题的线性规划松弛方法，对单台机器排序问题1｜prec｜∑wjCj介绍基于三个确定性线性规划松弛的2一近似算法，对平行机排序问题R｜rij｜（wjCj）介绍基于随机线性规划松弛的2-近似算法。这后一个算法对排序问题R｜（wjCj｜是3／2-近似算法．     

相似于线规划中单纯形解法的Lemke-Howson 方法的改进

参考文献中对Lemke—Howson算法给出了相似于线性规划中的单纯形解法．我们在参考文献中给出一个反例．本文对文献中给出的相似于线性规划中的单纯形解法的Lemke—Howson算法作出改进，     

关于Fujita型反应扩散方程组的Cauchy问题

本文研究Ｆｕｊｉｔａ型反应扩散方程组ｕｔ－Δｕ＝α１｜ｕ｜ｑ１－１ｕ＋β１｜ｖ｜ｐ１－１ｖ，（ｘ∈ＲＮ，ｔ＞０），ｖｔ－Δｖ＝α２｜ｕ｜ｑ２－１ｕ＋β２｜ｖ｜ｐ２－１ｖ，ｕ（ｘ，０）＝ｕ０（ｘ）０，ｖ（ｘ，０）＝ｖ０（ｘ）０，（ｘ∈ＲＮ）Ｌｐ解的整体存在性和有限时间Ｂｌｏｗ ｕｐ问题．这里ｑｉ＞１，ｐｉ＞１（ｉ＝１，２），α１０，α２＞０，β１＞０，β２０，１ｐ＋∞．     

动态系统中鞍点处的熵与分维

若ｆ（ｘ，ｙ）在不动点为鞍点的特征值满足λ１＞１＞｜λ２｜＞０，｜λ１·λ２｜＜１，则ｆ（ｘ，ｙ）限制在鞍点的局部有公式α＝１＋１ｎｒ是局部熵，α是局部分维数．把公式应用到Ｈｅｎｏｎ映射中，当α＝１．４，ｂ＝０．３时，得到１ｎｒ＝０．４５４，α＝１．２４４．     

关于单纯形表迭代法的一种提高计算精确度的方法

在计算机上进行分数运算时，会造成舍入误差，因此，用单纯形表迭代法解线性规划问题时，会因误差累积而改变问题解的性质。本文针对线性规划的单纯形表迭代法给出了一种提高计算精确度的方法     

二维可压缩Euler方程轴对称解的生命区间的下界

对于二维可压缩的Ｅｕｌｅｒ方程，当其初值满足ρ｜ｔ＝０＝ρ，ｄｉｖｖ｜ｔ＝０＝０，ｒｏｔｖ｜ｔ＝０＝εω１００时（０＜ε１），证明了对充分小的ε，存在常数ｂ＞０，使得其经典解的生命区间Ｔεｂｌｎ｜ｌｎε｜ε２．与文［５］中ｌｉｍε０＋ε２Ｔε＝＋∞的结论相比，本文的结果更为精确．     

线性规划最优解集的表现

文献［１］讨论了有无穷多最优解的线性规划问题，并利用最优单纯形表格的检验数给出线性规划有无穷多最优解的判别法，本文利用最优基可行解的凸组合及最优极向的非负线性组合给出线性规划最优解集的表现，从而把线性规划最优解集的几何特征阐释清楚．     

互补基解性质的应用研究

对线性规划互补基解性质进行了研究,得到了由线性规划问题最优基对应的单纯形表直接获得对偶线性规划问题最优基对应的单纯形表的一个有效方法,给出了应用实例.     

On the Equivalences of Matrix Norms Related to the l_p Norms

１．ＩｎｔｒｏｄｕｃｔｉｏｎＦｏｒａｐｏｓｉｔｉｖｅｎｕｍｂｅｒ１ｐ∞ａｎｄａｃｏｍｐｌｅｘｍａｔｒｉｘＡ＝（ａｉｊ）∈Ｃｎ×ｎ，ｗｅｄｅｎｏｔｅｂｙ｜Ａ｜ｐ＝ｎｉ，ｊ＝１｜ａｉｊ｜ｐ１ｐｔｈｅｌｐｎｏｒｍｏｆｔｈｅｍａｔｒｉｘＡ，ａｎｄｂｙＡ...     

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.     

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].