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1.
本文研究包含有一根部份嵌入的(辶回)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.
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   

3.
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   

4.
一、研究的任务和方法概念乃是一种反映对象和現象的一般的并且是本质的特征的思维形式。概念的形成是在人类历史发展过程中进行的,概念的掌握是掌握現成的、社会上形成的概念。所以概念的掌握就不需要通过概念形成时人类所走过的复杂的、漫长的道路。虽然如此,但是概念的掌握仍然是一种复杂的过程,它取决于过去的經驗、已有的知识、掌握过程中实现的活动(如教学活动、生活活动等)、掌握借以实現的智力过程的系统。概念的教学方法是多种多样的,主要可分为两种:一种是直接揭露本质特征的方法,另一种是間接揭露本质特征的方法(如变式、对比等)。在平面几何的概念的教学中应該采用直接揭露本质特征的方法还是采  相似文献   

5.
匈牙利数学家乔治·波利亚致力于解题的研究,为了回答"一个好的解法是如何想出来的"这个令人困惑的问题,他专门研究了解题的思维过程,并把研究所得写成<怎样解题>一书.在波利亚的解题表中,拟定计划是解题的关键环节,拟定计划的过程是在"过去的经验和已有的知识"基础上,探索解题思路的发现过程,是不断变换问题,把复杂的问题向简单的问题转化,陌生的问题向熟悉的问题转化,最终把待解决的问题化归为已解决的或易解决的问题的过程,其中善于联想又是转化的关键.下面通过一道习题的分析,体验这种联想转化的思维过程.  相似文献   

6.
1 大学校长多是数学家 经常关注数学教育的人可能会发现一个有趣的现象:国内许多大学的校长(包括现任的、离任的,以及正职、副职),都是数学专业出身,一些还是大名鼎鼎的数学家.比如:老一代的,1890-1920年间出生的就有云南大学的熊庆来、重庆大学(安徽大学)的何鲁、中国科大的华罗庚、复旦大学的苏步青、四川大学的柯召、南开大学的吴大任、上海大学的钱伟长等;  相似文献   

7.
郑忠国 《中国科学A辑》1984,27(12):1074-1088
本文讨论条件中位数的估计问题,证明了条件中位数的最近邻估计序列的渐近正态性。在讨论估计的误差的分布特性时,作者引用了Efron的Bootstrap方法。证明了在一定条件下,最近邻估计的误差的Bootstrap分布在渐近意义下是可用的。即估计量的误差的渐近分布与它的Bootstrsp统计量的渐近分布是相同的。  相似文献   

8.
文[1]介绍了余弦定理的向量式:以同一点为起点的任意两向量的数量积等于这个向量的模的平方和与这两个向量终点的连线段所表示的向量的模的平方的差的一半.如△ABC中,  相似文献   

9.
1.引言本文的工作主要是讨论非定常的热传导一对流问题的向后一步的Euler全离散化的非线性Galerkin混合元解的存在性及其误差估计.该工作是对山中的同一问题研究的第二部分.在第一部分[1],我们已经讨论了此问题的半离散化的情形.由于所研究的目标都是非定常的热传导一对流问题,其背景是相同的,在此将不重复了,请参考[1].本文的安排如下,52先回顾非定常的热传导一对流问题的混合元解的经典性质.53回顾半离散化的非线性Galerkin混合元解的性质,并导出后续讨论需要的一些关于时间导数的估计.54讨论向后一步的Euler全离散化…  相似文献   

10.
群G的一个L-模糊正规子群A的陪集做成的群G/A与群G的一个商群是自然同构的。如果f:G→G’是群的满同态,则G’的L-模糊正规子群做成的群与G的在f的核上取定值的L-模糊正规子群做成的群之间存在一个保序的双射。  相似文献   

11.
A study of the natures of the processes that are solutions of some finite difference stochastic equations, the right‐hand member of which is a stationary process, is given in the paper. Since the principal application of the present work concerns ARIMA models with or without seasonal variation, these processes are named G‐ARIMA. First, a criterion for a G‐ARIMA process to be stationary is established and some properties of a special class of stationary G‐ARIMA processes are studied. Then, we deduce some conditions for a finite difference stochastic equation to uniquely possess non‐stationary solutions. These have the particular property that their backward shift‐operator may be either a linear or a non‐linear operator, depending on the initial conditions of the solutions. So criteria are established for a non‐stationary G‐ARIMA process to have a bounded linear backward shift operator. Finally, some further properties of the G‐ARIMA processes are given, by comparing them with the broad class of V‐bounded processes. This comparison shows that a non‐stationary process cannot be at the same time G‐ARIMA and V‐bounded.  相似文献   

12.
选择Laplace-Beltrami算子Δ和Green算子G的复合算子Δ◇G为研究对象,首先证明了有界域的局部圆域上作用于齐次A-调和方程解的复合算子Δ◇G的带Radon测度的积分不等式,然后在此基础上得到有界域上全局的Radon积分不等式.  相似文献   

13.
We known that the maximal connected holomorphic automorphism group Aut (D)(0) is a semi-direct product of the triangle group T(D) and the maximal connected isotropic subgroup Iso(D)(0) of a fixed point in the complex homogeneous bounded domain D and any complex homogeneous bounded domain is holomorphic isomorphic to a normal Siegel domain D(VN,F). In this paper, we give the explicit formula of any holomorphic automorphism in T(D(VN, F)) and Iso(D(VN,F))(0), where G(0) is the unit connected component of the Lie group G.  相似文献   

14.
1 IntroductionThis paper is concerned with biholomorphic mappings between two bounded domains D andG both in C". Consequently, an important question is whether the domain D is biholomorphicto G? We give an answer for this question under a very weak condition.Let D be a bounded domain and Bn the unit ball in Cn. Let T(D) be the holomorphictangent bundle of D. We will identify T(D) with D × Cn. Let H(D1, D2) be the family ofholomorphic mappings from D1 to D2. We introduce the followin…  相似文献   

15.
The principal result is that if G is any irreducible subgroup of GL(n, C) (C the complex field) such that |tr(7^)| is uniformly bounded for all A in G and some fixed n × n nonzero matrix T, then G is equivalent to a unitary group. Similar results are proved for certain associated representations of G.  相似文献   

16.
The strong conical hull intersection property and bounded linear regularity are properties of a collection of finitely many closed convex intersecting sets in Euclidean space. These fundamental notions occur in various branches of convex optimization (constrained approximation, convex feasibility problems, linear inequalities, for instance). It is shown that the standard constraint qualification from convex analysis implies bounded linear regularity, which in turn yields the strong conical hull intersection property. Jameson’s duality for two cones, which relates bounded linear regularity to property (G), is re-derived and refined. For polyhedral cones, a statement dual to Hoffman’s error bound result is obtained. A sharpening of a result on error bounds for convex inequalities by Auslender and Crouzeix is presented. Finally, for two subspaces, property (G) is quantified by the angle between the subspaces. Received October 1, 1997 / Revised version received July 21, 1998? Published online June 11, 1999  相似文献   

17.
We prove that every locally connected quotient G/H of a locally compact, connected, first countable topological group G by a compact subgroup H admits a G-invariant inner metric with curvature bounded below. Every locally compact homogeneous space of curvature bounded below is isometric to such a space. These metric spaces generalize the notion of Riemannian homogeneous space to infinite dimensional groups and quotients which are never (even infinite dimensional) manifolds. We study the geometry of these spaces, in particular of non-negatively curved homogeneous spaces. Dedicated to the memory of A. D. Alexandrov  相似文献   

18.
G可积函数的Lebesgue可测性   总被引:1,自引:0,他引:1  
Botsko在连续和可导的知识基础上推广了Riemann积分,得到了一种新的积分,称为G积分.G积分既不同于Riemann积分也不同于Lebesgue积分.本文通过对G积分的研究,得到了G可积函数一定Lebesgue可测,从而有界G可积函数一定Lebesgue可积;同时我们还证明了这两个积分值相等.  相似文献   

19.
The principal result is that if G is any irreducible subgroup of GL(n, C) (C the complex field) such that |tr(7^)| is uniformly bounded for all A in G and some fixed n × n nonzero matrix T, then G is equivalent to a unitary group. Similar results are proved for certain associated representations of G.  相似文献   

20.
记G为一有界局部紧的Vilenkin群.我们引进了G上的一类Calderon-Zygmund型算子,并且证明了它们的加权LP(G)有界性.另外还给出了这些结果的一些应用.  相似文献   

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