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1.
本文研究包含有一根部份嵌入的迴转轴的半空间的性质.不用知道一给定的嵌入的轴的扭转问题的精确解,这些性质能指出此半空间的位移或应力场的某些特点并且有时可以用来检查数值解.文中给出嵌入半空间的受扭的刚性圆柱的轴的表面上的正确的应力分布的检查的例子.  相似文献   

2.
通过含单位元的交换环的实素理想构造出对应的模的实素子模,得到模的序存在的一个充要条件,并对模的所有序的支集的交集(文中称作"模的核心")作出一定的刻划,找到了判断模中的元素属于模的核心的充要条件.  相似文献   

3.
(四)罗氏几何的光辉照亮了科学前进的道路我们来分析他的学说的哲学意义.在罗氏的时代,哲学中占统治地位的思想是康德的"不可知论",按照这批人的说法,客观世界是存在的,但是不可知的,时间空间是人心的创造,是人心给经验安排的秩序,我们所确实知道的世界的规律性是人心按先天的原则所创造出来的,先天就是与经验无关的,这样,我们的空间观念就完全是人心的创造,  相似文献   

4.
1 重、难点分析关于映射与函数的概念 ,重点是映射、函数的概念的理解与掌握 ,难点是对映射、函数概念 ,对函数符号 y =f(x) ,以及对函数是一种特殊的映射的理解 ,对函数的定义域、值域的理解与掌握 .对于函数的单调性和奇偶性 ,重点是对函数的单调性、奇偶性的概念的理解 ,难点是对函数的单调性、奇偶性的判断与应用 .关于反函数 ,重点是反函数的概念的理解 ,难点是对求反函数的方法的掌握 .关于指数、指数函数 ,重点是分数指数幂的概念和分数指数幂的运算性质、指数函数的图象和性质的理解与掌握 ,难点是根式的概念和分数指数幂的概念…  相似文献   

5.
1本单元重点、难点分析三角函数是中学数学的重要内容之一,也是高等数学的重要基础。本单元首先将角的概念进行推广,并引入弧度制的表示方式,再定义六种三角函数,然后探讨同角三角函数间的一些基本关系式及三角函数的诱导公式。角的概念的推广和角的度量单位的更新(引入弧度制)是本单元的第一个重点,它拓宽了三角函数的应用范围,简化了三角函数的研究,是进一步学习三角函数的基础,起到了承上启下的作用.任意角的三角函数的定义是进一步学习三角函数的根基,由此导出的三角函数的符号、同角三角函数间的基本关系式及三角函数的诱导公式是本单…  相似文献   

6.
最近20—30年来在调节过程的研究中微分差分方程得到很多的应用.在调节理论和在很多其他具有时滞的过程的理论中所发生的基本问题中的一个问题是关于过程的稳定性的问题,一般化为关于微分差分方程解的稳定性的问题.这具问题吸引了非常多的工作者的注意(参考交末的目录),但据我们所知,这些零散的研究从未被有系统地综述过.这篇文章的目的是用简要的形式综述关于微分差分方程解的稳定性的工作的结果,也包括本文作者的若干研究在内.  相似文献   

7.
一个方程的解可以看作两个函数的图象的交点的横坐标。反过来,方程的解又可以反映两个函数之间的某种关系,即它们的图象相交的情况。因此,可以利用函数的性质对方程的解,特别是直接求解很困难的某些超越方程的解的情况作出定性的讨论。也可以利用方程的解对函数的图象间的交点个数作出定量的研究,本文主要通过对函数y=x~(1/x)和y=x~x的性质的分析,就方程a~x=x和a~x=loga~x等的解的情况进行讨论。  相似文献   

8.
利用二次曲线的切线的定义,分别讨论过二次曲线上的一点的切线的求法及过二次曲线外的一点的切线的两种求法,并且得到了存在奇异点的二次曲线的具体类型.  相似文献   

9.
利用Koszegi与Rabin的参照依赖效用函数对报童问题进行了研究,不仅求得基于预期的损失厌恶报童的最优订货量而且讨论了它的性质.研究发现,基于预期的损失厌恶的报童的订货量要低于利润最大化的报童的订货量,而且,基于预期的损失厌恶的报童的订货量随预期利润、损失厌恶程度的增加而减少.  相似文献   

10.
左可正 《数学杂志》2008,28(3):303-307
本文研究了矩阵A的外逆的表达式,利用外逆及分块矩阵的秩的性质,得出了A的两个外逆的线性组合还是A的外逆的完全分类,不仅证明了A的两个外逆的和与差,而且A的外逆的几个充要条件,推广了Jerzy K.Baksalary和Oskar Maria Baksalary的结果.  相似文献   

11.
12.
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.  相似文献   

13.
张丽娜  吴建华 《数学进展》2008,37(1):115-117
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  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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).  相似文献   

17.
18.
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  相似文献   

19.
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.  相似文献   

20.
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].  相似文献   

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