首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 984 毫秒
1.
In pattern analysis and image management, the information of an objective image can be recovered from a sequence approximate images. In mathematical form of expression it is needed to consider some types of continuity. Many researchers defined the limit and the upper limit of a sequence and, using the concepts, characterized continuity in the space consisted of images. In the present paper, the authors give firstly some examples to show that there are some theoretical shortcomings in those results, then give some corresponding correct results.  相似文献   

2.
In this paper, we study the complete bounded λ-hypersurfaces in the weighted volume-preserving mean curvature flow. Firstly, we investigate the volume comparison theorem of complete bounded λ-hypersurfaces with |A|≤α and get some applications of the volume comparison theorem. Secondly, we consider the relation among λ, extrinsic radius k, intrinsic diameter d, and dimension n of the complete λ-hypersurface,and we obtain some estimates for the intrinsic diameter and the extrinsic radius. At last, we get some topological properties of the bounded λ-hypersurface with some natural and general restrictions.  相似文献   

3.
Using the Nevanlinna theory of the value distribution of meromorphic functions and theory of differential algebra, we investigate the problem of the forms of meromorphic solutions of some specific systems of generalized higher order algebraic differential equations with exponential coefficients and obtain some results.  相似文献   

4.
In this paper, the author establishes the embedding theorems for different metrics of inhomoge-neous Besov and Triebel-Lizorkin spaces on spaces of homogeneous type. As an application, the author obtains some estimates for the entropy numbers of the embeddings in the limiting cases between some Besov spaces and some logarithmic Lebesgue spaces.  相似文献   

5.
杨世国 《东北数学》2005,21(2):221-226
Using theory of distance geometry and analytic method, the problem on relations about the volumes of some simplices is studied, and some new inequalities for the volumes of simplices are established. As special cases, an inequality for the volume of the pedal simplex of a simplex and other inequalities for simplices are gotten.  相似文献   

6.
This paper studies the reachability and the structure of reachable semigroup of bilinear control systems on Lie group. In the second section some equivalency lemmas are given, which not only simplify the proofs of the main results, but discover some properties of systems also. In the third section some conditions are advanced that the reachable semigroup of system is weakly symmetric by means of the study of one prameter subgroups. This study is discussed by manifold theory and matrix theory, respectively. In the last seetion, some topological properties of the reachable semigroup are advanced.  相似文献   

7.
We mainly discuss the invariance of some subclasses of biholomorphic mappings under the generalized Roper-Suffridge operators on Bergman-Hartogs domains which are based on the unit ball Bn. Using the geometric properties and the distortion results of subclasses of biholomorphic mappings, we obtain the geometric characters of almost spirallike mappings of type β and order α, S_?~*(β, A, B), strong and almost spirallike mappings of type βand order α maintained under the generalized Roper-Suffridge operators on Bergman-Hartogs domains. Sequentially, we conclude that the generalized operators and the known operators preserve the same properties under some conditions. The conclusions generalize some known results.  相似文献   

8.
In this paper, we discuss the dynamics of quitting smoking with Beddington-Deangelis function. Firstly, the basic reproduction number of the model is obtained by establishing the basic reproduction matrix. Then, by using the Routh-Hurwitz criterion and Lyapunov functionals and LaSalle’s Invariant Principle and the second additive compound matrix, local and global dynamics of the model are analyzed. Based on the partial rank correlation coefficients (PRCCs), we discuss some biological implications and focus on the impact of some key model parameters. Finally, the numerical simulations show the theoretical analysis more intuitively, and we give some strategies to control the spread of smokers.  相似文献   

9.
In this paper, using fixed point method, discusses the problem of periodic solution for a class of degenerate neutral periodic system with delay, and obtains some sufficient conditions for the existence and uniqueness of periodic solution of the system, the result extends and improves some results of paper [1-2].  相似文献   

10.
Here we discuss some phenomena of equiconvergence for the functions analytic inside the lemniscate. A quantitative estimate of sequences of differences between the Jacobi polynomials and Lagrange interpolants and some other results are obtained.  相似文献   

11.
张庆彩 《东北数学》2007,23(2):103-114
In this paper we study the problem of meromorphic functions sharing three sets and obtain some theorems which are the extension and complement of some known relative results given by Yi Hongxun and others.  相似文献   

12.
主要研究具1 IM分担值的整函数的唯一性问题,获得的定理推广了林伟川,方明亮,华歆厚,C.C.Yang等人的系列结果.  相似文献   

13.
张庆德  秦春艳 《数学学报》2008,51(1):145-152
根据Nevanlinna理论讨论了一族亚纯函数中每个函数与其k(k为任一正整数)阶导数单向分担3个有限复值时的正规性,并举例说明这一结果是精确的.  相似文献   

14.
Meromorphic Functions Sharing Two Values   总被引:2,自引:0,他引:2  
By using the idea of weighted sharing of values, the problem of uniqueness of meromorphic functions that share two values is studied. The results in this paper improve some theorems given by M. Ozawa and Yi Hongxun et al.  相似文献   

15.
In this article, we use Zalcman Lemma to investigate the normal family of meromorphic functions concerning shared values, which improves some earlier related results.  相似文献   

16.
徐耀  张庆彩 《数学杂志》2015,35(1):110-122
本文研究了涉及重值的具有四个公共小函数的亚纯函数的唯一性问题.利用关于小函数的Nevanlinna第二基本定理精简形式及处理小函数的有关方法,改进了有关结果.利用Gundersen处理公共值对的方法,对具有五个IM公共值对和四个IM公共小函数对的亚纯函数的情况作了进一步讨论,推广改进了相关结果.  相似文献   

17.
In this paper, we study the normality of families of meromorohic functions related to a Hayman conjecture. We prove that the conditions in Hayman conjecture and in other criterions can be relaxed. The results in this paper improve some previous results.  相似文献   

18.
本文研究了全纯函数族的正规性问题.利用Zalcman引理,证明了全纯函数族的几个正规定则,推广了Montel正规定则.  相似文献   

19.
王建平 《数学杂志》2006,26(1):31-36
本文利用Gundersen的方法研究了一个线性微分方程的解并证明此方程的每一个整函数解的级必为无穷,推广了Gundersen和杨连中的若干结果。作为应用,我们还研究了与导数具有公共不动点的整函数.  相似文献   

20.
用简单的方法证明了全纯函数族的一个正规定则,推广了Montel正规定则.设F为区域D上的一个全纯函数族,其零点是重级的,a为有限复数.如果f,g∈F,有(f-1)f′与(g-1)g′分担a,则F正规.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号