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1.
In this note, first, we give a very short new proof of the theorem which yields a lower bound for the surface area of Voronoi cells of unit ball packings in E d and implies Rogers' upper bound for the density of unit ball packings in E d for all d ≥ 2. Second we sharpen locally a classical result of Gauss by finding the locally smallest surface area Voronoi cells of lattice unit ball packings in E 3. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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Rodin and Sullivan (1987) proved Thurston's conjecture that a scheme based on the Circle Packing Theorem converges to the Riemann mapping, thereby proved a refreshing geometric view of the Riemann Mapping Theorem. Naturally, we consider to use the ellipses to pack the bounded simply connected domain and obtain similarly a sequence simplicial homeomorphism between the ellipse packing and the circle packing. In this paper, we prove that these simplicial homeomorphism approximate a quasiconformal mapping from the bounded simply connected domain onto the unit disk with the modulus of their complex dilatations tending to 1 almost everywhere in the domain when the ratio of the longer axis and shorter axis of the ellipse tending to ∞.  相似文献   

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1IntroductionandNotationsLetfi={p=(x,yiz)ER3,IPI=1}betheunitsphereintheEuclideanspaceR3.ByC(O)andLP(O),1SP相似文献   

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本文研究了单位圆内v值代数体函数的聚值点的存在性.利用覆盖曲面的几何方法,证明了单位圆内满足一定条件的v值代数体函数的聚值点存在性定理,并解决了李国平院士提出的一个问题和一个猜想.  相似文献   

5.
周积团 《数学杂志》2005,25(4):379-382
本文研究了在复合∧-∨下格矩阵幂序列的收敛性,利用格中∧与∨运算的特性,获得了格矩阵幂序列的一些性质,证明了在∧-∨复合下.任一个几乎非自反格矩阵的幂序列是递减与收敛的.  相似文献   

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In this paper, we study the growth of the solutions for 1st kind of differential equations of higher order in the unit disc. We give a sufficient condition for all solutions of second order linear differential equation to be inadmissible and a sufficient condition for all solutions of higher order linear differential equation to be of infinite order.  相似文献   

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称f:U→E为向量值解析函数(这里U为复平面上开集,E为复Banach空间),如果对于任意的E对偶空间中的元素有f为复值解析函数[1].单复变中最大模原理指出:在内点达到最大模的解析函数,必为常值映射。该相应结论在向量值解析函数中不成立[1],所以有必要研究模恒为1的并非常值的向量值解析函数。为此,作者引进了Banach空间单位球面上三种等价关系,利用它们等价类为凸集的性质,以及它们与模恒为1的向量值解析函数的关系,导出一系列结论。其中较有趣的是:f:U→E为模恒为1的并非常值的向量值解析函数,且f(U)E的有限维子空间,则存在e0,e∈E-{θ}(θ为E的零元),使得‖e0+ze1‖=1,|z|<1。  相似文献   

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本文旨在提出单位球面上的一种Hermite插值格式.为此,本文首先研究了沿球面同轴圆周组上的Hermite插值问题,给出了三种适定的插值泛函组.然后研究了球面上的Hermite插值问题,给出了球面上Hermite插值的一种叠加插值法,即添加圆周组法.进一步将二者结合,导出了一类球面上Hermite插值的适定插值泛函组.为了说明这类适定插值泛函组的构造方法,在本文最后还给出了构造球面上低次Hermite适定插值泛函组的一些具体例子和数值算例.  相似文献   

10.
Throughout this paper,D=(d_1,d_2,...,d_n)denote a sequence of nonnegative inte-gers.We let(?)(D)denote the class of all graphs with degree sequence D,or equally,theclass of all symmetric(0,1)--matrices with trace 0 and row sum vector D.The structure matrix S=S(D) of D is a matrix of order n+1,whose entries are  相似文献   

11.
关于Rn中实单位球上M-调和BMO函数的Carleson测度特征   总被引:1,自引:0,他引:1  
本文讨论了实单位球上的平均有界振动M-调和函数的Carleson测度特征,证明了Mobius不变调和函数f(x)属于BMOH或VMOH当且仅当dμ(x)=(1-|x|2)| (△)f(x)|2dv(x)是Carleson测度或紧 Carleson测度.  相似文献   

12.
一类循环码的极小距离   总被引:1,自引:0,他引:1  
高莹 《数学杂志》2002,22(2):165-168
循环码的极小距离大于或等于BCH界。本文考虑的是极小距离等于BCH界的特殊情形。利用一类自反循环码的事实。证明了使循环码的极小距离等于其BCH界的两个充分条件;并指出极小距离等于任意给定值,维数任意大的循环码可以构造。  相似文献   

13.
1引 言 单位球面上的插值问题一直是三元插值问题中比较受关注的部分.近年来,球面上的 Lagrange插值问题已经得到了很好地解决.例如[1]中给出了构造单位球面上的Lagrange 插值适定结点组的一种方法:添加圆周法.[2]和[3]中研究了单位球面上的多项式插值问题,给出了构造单位球面上的插值适定结点组的另外两种方法.  相似文献   

14.
We study the distribution of the number of lattice points lyingin thin elliptical annuli. It has been conjectured by Bleherand Lebowitz that if the width of the annuli tends to zero andtheir area tends to infinity, then the distribution of thisnumber, normalized to have zero mean and unit variance, is Gaussian.This has been proved by Hughes and Rudnick for circular annuliwhose width shrinks to zero sufficiently slowly. We prove thisconjecture for ellipses whose aspect ratio is transcendentaland strongly Diophantine, also assuming the width shrinks slowlyto zero.  相似文献   

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Cycle base theory of a graph has been well studied in abstract mathematical field such matroid theory as Whitney and Tutte did and found many applications in pratical uses such as electric circuit theory and structure analysis, etc. In this paper graph embedding theory is used to investigate cycle base structures of a 2-(edge)-connected graph on the sphere and the projective plane and it is shown that short cycles do generate the cycle spaces in the case of ““““small face-embeddings““““. As applications the authors find the exact formulae for the minimum lengthes of cycle bases of some types of graphs and present several known results. Infinite examples shows that the conditions in their main results are best possible and there are many 3-connected planar graphs whose minimum cycle bases can not be determined by the planar formulae but may be located by re-embedding them into the projective plane.  相似文献   

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Menger PN空间中的固有值与固有元   总被引:4,自引:0,他引:4  
本文提出了Menger PN空间中固有值和固有元的新概念,研究了M—PN空间中的固有值与固有元的若干问题,得到了几个重要的结论.  相似文献   

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