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91.
Richard F. Patterson 《Southeast Asian Bulletin of Mathematics》2000,24(3):421-429
The definition for the convergence of a double sequence was presented by A. Pringsheim [9]. Recently, the definitions of limit inferior, limit superior, and the core of a double sequence are presented. By using these definitions and the notion of regularity for four-dimensional matrices, an invariant core theorem for double sequences is presented.AMS Subject Classification (2000) primary 40B05 secondary 40C05 相似文献
92.
Xiao Qian WANG Shi Hong CHENG 《数学学报(英文版)》2005,21(5):1121-1130
In Part Ⅰ the concept of the general regular variation of n-th order is proposed and its construction is discussed. The uniqueness of the standard expression and the higher order regularity of the auxiliary functions are proved. 相似文献
93.
E. M. Abbasov O. A. Dyshin B. A. Suleimanov 《Computational Mathematics and Mathematical Physics》2008,48(12):2194-2210
A method is proposed for constructing stable approximate wavelet decompositions of weak solutions to boundary value problems for the unsteady porous-medium flow equation with discontinuous coefficients and inexact data. The method is based on the general scheme for finite-dimensional approximation in Tikhonov regularization and on multiresolution analysis with basis functions defined as the product of one-dimensional Daubechies wavelets. 相似文献
94.
In this note, we enumerate all nonisomorphic 3‐factorizations of K10. © 2001 John Wiley & Sons, Inc. J Combin Designs 9: 379–383, 2001 相似文献
95.
朱玉扬 《数学的实践与认识》2008,38(4):142-148
记平面边长为1的正m边形为S_m,将S_m剖分成n块:S_(m1),S_(m2),…,S_(mn),这样的剖分称S_m的n剖分,并以T(m,n)表示.以d_(mi)表示区域S_(mi)(i=1,2,…,n)的直径(即区域S_(mi)任意两点之间距离的最大者).记D(m,n)=max{d_(m1),d_(m2),…,d_(mn)}及Ψ(m,n)=■{D(m,n)}.本文将估计Ψ(m,n)的上下界.证明Ψ(6,3)=3/2,Ψ(6,4)=3-3~(1/2),Ψ(6.6)=1,Ψ(6,7)=3/2,估计Ψ(6,n)的渐进性.提出几个猜想. 相似文献
96.
Ali Reza Moghaddamfar 《Siberian Mathematical Journal》2006,47(5):911-914
The noncommuting graph ?(G) of a nonabelian finite group G is defined as follows: The vertices of ?(G) are represented by the noncentral elements of G, and two distinct vertices x and y are joined by an edge if xy ≠ yx. In [1], the following was conjectured: Let G and H be two nonabelian finite groups such that ?(G) ? ?(H); then ¦G¦ = ¦H¦. Here we give some counterexamples to this conjecture. 相似文献
97.
In this paper, the “FLIC” difference method with triangular mesh is adopted to numerically simulate the regular and Mach reflections
that occur when a shock wave pass around a wedge. The compuational result is compared with the shock tube experimental results
of G. Ben-Dor and I. I. Glass. The comparison shows that the position, shape of shock wave and height of Mach stem all show
a good agreement. Consequently, the “FLIC” difference method with triangular mesh is quite satisfactory in numerical simulation
of the regular and Mach reflections. 相似文献
98.
通过引用P-平坦模的定义,引入了右IPF环的概念,推广了右IF环的概念,这对研究IF环及QF环具有重要的作用,同时对右IPF环的性质作了一些刻画,得到了右IPF环的若干个等价命题;最后,用P-平坦模及右IPF环推出了正则环的一些等价条件. 相似文献
99.
In this paper, we consider the problem where λ is a spectral parameter; q(x) ∈ L1(0,1) is complex‐valued function; αs, s = 1,2,3, are arbitrary complex constants that satisfy α2 = α1 + α3 and σ = 0,1. The boundary conditions of this problem are regular, but not strongly regular. Asymptotic formulae for eigenvalues and eigenfunctions of the considered boundary value problem are established. It is proved that all the eigenvalues, except for finite number, are simple and the system of root functions of this spectral problem forms a basis in the space Lp(0,1), 1 < p < ∞ , when ; moreover, this basis is unconditional for p = 2. We note that the considered problem was previously investigated in the condition of α2 ≠ α1 + α3. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
100.
本文研究了半平面内无穷级Dirichlet级数的正规增长性问题.利用型函数的方法,获得了关于无穷X级的正规增长性的几个等价定理,推广了已有的结果. 相似文献