Finsler流形上Laplace比较定理及其应用

本文研究了Finsler流形上距离函数的Laplacian.利用Schwarz不等式和[5]中主要方法,获得了具有负曲率的Laplacian比较定理,进而得到了Finsler流形上第一特征值的下界估计.     

无序和的一个注记

对于任意集合上广义实数取值的非负函数,文献[1]给出了无序和的两种定义,文献[2]给出了无序和的第三种定义,文章证明了这三种定义相互等价.对于任意集合上绝对可和的复值函数,文献[1]和文献[2]分别给出了无序和的两种不同定义,文章证明了这两种定义等价.     

含有解析函数与亚纯函数的一些不等式

指出文献 [2 ]和文献 [4]中的错误 ,并且得到含有单位圆盘内接解析函数与亚纯函数的几个不等式 .     

非奇函数是M序列反馈函数的一个充要条件

本文第1段系将文献[2]中所引进的M序列反馈函数用标号表示的概念推广为非奇反馈函数的标号表示法.文献[3]在第 2章里给出了非奇函数是M序列反馈函数的一些必要条件,而在本文第2段则根据文献[2]中的剪接法与有关结论给出了非奇函数是M序列反馈函数的一个充分与必要条件.     

基于结构元线性生成的复Fuzzy值函数项级数

文献[1]中提出了基于结构元理论的Fuzzy数项级数的概念,文献[2]、文献[3]、文献[4]对其收敛性进行了探讨,文献[5]、文献[6]对模糊值函数项数列及级数进行了研究。本文在此基础上给出了基于结构元线性生成的复Fuzzy值函数项数列及级数的定义,同时对复Fuzzy值函数项级数的一些重要性质进行了研究,并给出了相应定理。     

基于模糊结构元的模糊级数

在文献[1]中提出的模糊结构元概念及文献[4]中的得到的[-1,1]上同序标准单调有界函数类与有界模糊数空间同胚性质基础上,本文给出了基于模糊结构元的模糊数项级数和模糊值函数项级数定义,对其重要性质进行了讨论.     

复合函数的可积性及应用

可积函数的复合未必是可积的.本文给出了一个复合函数可积的充分条件,并拓广了文献[6]中册P44定理7.4.7的结果,利用该结果简化了文献[5]上册P252定理10.1的证明.     

悬臂板侧屈问题的多项式解法

本文研究了悬臂矩形板受均布载荷或集中载荷作用时的侧屈问题.挠度函数选用多项式(2.1)以取代文献[1]中的余弦函数.本文得到的最小临界载荷比文献[1]相应结果更加准确,计算过程也十分简单.     

Laplace方程斜边值问题的梯度估计

该文介绍了Laplace方程斜边值问题解的梯度估计的两种证明方法:第一种证明重新整理文献[1]中的梯度估计;第二种证明采用不同于文献[1]的辅助函数得到估计.两种方法都充分利用函数在极大值点的性质,得到边界梯度估计和近边梯度估计,结合文献[2]中已有的梯度内估计,从而得到解的全局梯度估计.     

基于规则修改的Fuzzy控制自调整函数设计讨论

在综述了文献[1]、[2]、[4]中对多因子调整方法的基础上,介绍了在模糊控制领域,基于规则修改的自适应Fuzzy控制器自调整函数的设计方法和思想.     

On the Laplacian coefficients of graphs under some transformations

We generalize three approaches on graph transformations, respectively, from Stevanovi? and Ili? (2009) [16] and Tan (2011) [19]. We also generalize an approach of graph transformations on the spectral radius of adjacency matrix into the Laplacian coefficients of graphs from Li and Feng (1979) [26]. Moreover, we determine the unique tree having the third maximal Laplacian coefficients among all n-vertex trees.     

超图的Laplacian

本文讨论了由Ｆ．Ｒ．Ｋ．Ｃｈｕｎｇ 引入的ｋ－图的Ｌａｐｌａｃｉａｎ 的一些基本性质．通过引入ｋ－图的邻接图的概念,得到了ｋ－图的Ｌａｐｌａｃｉａｎ 及其特征多项式的更明确的表达式．同时,也改进了文［１］中关于ｄ－正则ｋ－图的谱值的一个下界     

Boundedness of Commutators Generated by Campanato-type Functions and Riesz Transforms Associated with Schrdinger Operators

Let■=-△+V be a Schrdinger operator on R~n,n3,where △is the Laplacian on R~n and V≠0 is a nonnegative function satisfying the reverse Holder's inequality.Let[b,T]be the commutator generated by the Campanatotype function b∈■ and the Riesz transform associated with Schrdinger operator T=▽(-△+V)~(-1/2).In the paper,we establish the boundedness of[b,T]on Lebesgue spaces and Campanato-type spaces.     

The minimum Laplacian spread of unicyclic graphs

The Laplacian spread of a graph [1] is defined as the difference between the largest eigenvalue and the second-smallest eigenvalue of the associated Laplacian matrix. In this paper, the minimum Laplacian spread of unicyclic graphs with given order is determined.     

Singularities of the solution of the laplacian in domains with circular edges

In this paper we generalize the results from [4] to special domains with curved edges. For general elliptic boundary value problems the behavior of the solutions near arbitrary, smooth edges is analyzed by Maz'ja and Rossmann [3]. First following Dauge [1] we derive a regularity theorem for the solution of the Dirichlet problem of the Laplacian with a decomposition into edge singularities of nontensor product form. In this case the regularity of the remainder term in the decomposition corresponds to the one in the two-dimensional case [2]. Following [4] we obtain a refined decomposition where all singularity terms are of tensor product form. We illustrate our results with several examples.     

Radial symmetry for systems of fractional Laplacian

In this paper, we consider systems of fractional Laplacian equations in Rnwith nonlinear terms satisfying some quite general structural conditions. These systems were categorized critical and subcritical cases. We show that there is no positive solution in the subcritical cases, and we classify all positive solutions ui in the critical cases by using a direct method of moving planes introduced in Chen-Li-Li [11] and some new maximum principles in Li-Wu-Xu [27].     

An optimal parabolic estimate and its applications in prescribing scalar curvature on some open manifolds with Ricci \ge 0

By establishing an optimal comparison result on the heat kernel of the conformal Laplacian on open manifolds with nonnegative Ricci curvature, (a) we show that many manifolds with positive scalar curvature do not possess conformal metrics with scalar curvature bounded below by a positive constant; (b) we identify a class of functions with the following property: If the manifold has a scalar curvature in this class, then there exists a complete conformal metric whose scalar curvature is any given function in this class. This class is optimal in some sense; (c) we have identified all manifolds with nonnegative Ricci curvature, which are “uniformly” conformal to manifolds with zero scalar curvature. Even in the Euclidean case, we obtain a necessary and sufficient condition under which the main existence results in [Ni1] and [KN] on prescribing nonnegative scalar curvature will hold. This condition had been sought in several papers in the last two decades. Received: 11 November 1998 / Revised: 7 April 1999     

Some results on the ordering of the Laplacian spectral radii of unicyclic graphs

A unicyclic graph is a graph whose number of edges is equal to the number of vertices. Guo Shu-Guang [S.G. Guo, The largest Laplacian spectral radius of unicyclic graph, Appl. Math. J. Chinese Univ. Ser. A. 16 (2) (2001) 131–135] determined the first four largest Laplacian spectral radii together with the corresponding graphs among all unicyclic graphs on n vertices. In this paper, we extend this ordering by determining the fifth to the ninth largest Laplacian spectral radii together with the corresponding graphs among all unicyclic graphs on n vertices.