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1.
This note gives an explicit lower bound of the function (?)(t) in the lemma of DiPerna and Chen and some remarks.  相似文献   

2.
In this note, we consider a holomorphic mapping f from the unit disk D in C to p-ball Bp={z ∈Cn:∑ni=1|zi|p1},1p+∞. It is proved that for such f,|▽||f||(z)|≤1-||f(z)||2/1-|z|2,z∈D.The extremal problem is also discussed when p is an even number. This result extends some related results on Schwarz lemma.  相似文献   

3.
We are concerned with the sets of quasi generic points in finite symbolic space. We estimate the sizes of the sets by the Billingsley dimension defined by Gibbs measures. A dimension formula of such set is given, which generalizes Bowen's result. An application is given to the level sets of Birkhoff average.  相似文献   

4.
本又把Weaklyarbitrage-free和Striedyarbitrage-free从Eadidean空间拓广到无限维空间,从而得到拓广的Minkowski-Farkas引理和Stiemke引理.  相似文献   

5.
To answer the rest part of the problem of Boas R. P. on derivative of polynomial, it is shown that if $\[p(z)\]$ is a polynomial of degree n such that $\[\mathop {\max }\limits_{\left| z \right| \le 1} \left| {p(z)} \right| \le 1\]$ and $\[{p(z) \ne 0}\]$ in $\[\left| z \right| \le k,0 < k \le 1\]$, then $\[\left| {{p^''}(z)} \right| \le n/(1 + {k^n})\]$ for $\[\left| z \right| \le 1\]$. The above estimate is sharp and the equation holds for $\[p(z) = ({z^n} + {k^n})/(1 + {k^n})\]$.  相似文献   

6.
Based on Bernstein's Theorem, Kalandia's Lemma describes the error estimate and the smoothness of the remainder under the second part of Holder norm when a Holder function is approximated by its best polynomial approximation. In this paper, Kalandia's Lemma is generalized to the cases that the best polynomial is replaced by one of its four kinds of Chebyshev polynomial expansions, the error estimates of the remainder are given out under Holder norm or the weighted Holder norms.  相似文献   

7.
廖山涛 《数学学报》1957,7(2):183-199
<正> 在§1我们界说了局部乘积,它关联 Hausdorff 紧致空间 X 中闭子集X_0的同调以及 X_0在 X 中邻域的同调.在流形与有边流形上的 Poincaré-Alexander-Lefschetz 型对偶定理可以用这种局部乘积表示(§2).在§3,我们研讨了一类所谓摹流形状空间.局部的下调群与上调群的概念在 [3,233—263页;8]中曾不明显地使  相似文献   

8.
给出了两流形上半鞅的互变差。  相似文献   

9.
越民義 《数学学报》1956,6(1):35-54
<正> §1.本文的主要目的是要證明下面的結果: 定理1.設q_1,q_2為二正整數.合  相似文献   

10.
ON THE SHEAF OF GENERALIZED FUNDAMENTAL GROUP AND COVERING SPACE¥GANDANYANAbstract:Theauthorconstructsthesheafofgeneralizedfu...  相似文献   

11.
P. Rosenthal introduced the following property(P):If u is any reductive algebra and T∈u', then T~*∈u'.In this note, the author proves(1) A reductive spectral operator with polynomially compact quasinilpotent part has property(P);(2) A reductive spectral operator with algebraic quasinilpotent part has property(P);(3) The countable direct sum of scalar operators has property(P);(4) If T is reductive and T is quasi-similar to a polynomially compact operator, then T is normal.  相似文献   

12.
Abstract

A semi-quantitative theory of covering metric spaces is studied; the theory, involving the concept of a ‘fine cover’, has proved useful in complex analysis. We obtain general results on fine covers, and put forward some conjectures. Most of these remain unanswered (and indeed seem most difficult to answer) for subsets of the real line.  相似文献   

13.
黎先华 《数学杂志》2004,24(2):145-146
本文改进了J .G .Thompson在JournalofCombinatorialTheory ,1 (1 96 6 )中得到的一个有用的引理的结果 .  相似文献   

14.
15.
关于分担值与正规性的─点注记   总被引:6,自引:0,他引:6  
本文证明了如下定理:设是区域D内的一族亚纯函数,a是一非零有穷复数,k是一正整数。若对于任意有在D内f≠0且f与f(k)分担a,则在D内正规.  相似文献   

16.
於坤瑞  徐广善 《数学学报》1979,22(4):487-494
<正> 对任意实数x,定义‖x‖=max(x-[x],[x]+1-x).设a_1,…,a_(k-1)是互不相等的非零整数,a是适合(a,a_1,…,a_(k-1)=1的正整数,r是正整数.置  相似文献   

17.
《Quaestiones Mathematicae》2013,36(3):279-291
ABSTRACT

In the general setting of a complete, well-powered category A, we define and study two universal closure operations: regularization and extremalization, by means of regular and extremal subobjects of A. respectively. A general theorem of characterization of epimorphisms in A is given. When A is an epireflective subcategory of TOP, such operations are shown to coincide with A-closure [11] and epiclosure [2]. respectively. In the topological contest, regularization and extremalization are studied in detail and compared with r-closure, defined in [13].  相似文献   

18.
Given a topological dynamical system(X,T) and a T-invariant measure μ,let B denote the Borel σ-algebra on X.This paper proves that(X,B,μ,T) is rigid if and only if(X,T) is μ-A-equicontinuous in the mean for some subsequence A of N,and a function f ∈L2(μ) is rigid if and only if f is μ-A-equicontinuous in the mean for some subsequence A of N.In particular,this gives a positive answer to Question 4.11 in [1].  相似文献   

19.
《Quaestiones Mathematicae》2013,36(3-4):467-478
Abstract

In this paper we introduce the notions of uniform complete regularity and uniform normality for nearness frames with the view of obtaining new and pointfree proofs of some known topological results.  相似文献   

20.
彭良雪 《数学杂志》2005,25(6):611-617
引入了两个很有联系的空间类JHB-空间与强J HB-空间,分别推广了J-空间与强J-空间.讨论了J-空间、强J-空间、J HB-空间及强JHB-空间类间的相包含关系及此四空间类逆包含的条件,还得到了JHB-空间的内部刻画,并证明了若对每个α∈S,Xα.都是非紧的连通空间,则积空间∏α∈S Xα是强J-空间。  相似文献   

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