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111.
SHEN Yuliang 《中国科学A辑(英文版)》2000,43(9):929-936
Given a quasisymmetric homeomorphismh of the unit circle onto itself, denote byK
n
*
,H
h
andK
h
the extremal maximal dilatation, boundary dilatation and maximal dilatation ofh, respectively. It is proved that there exists a family of quasisymmetric homeomorphismsh such thatK
h
<H
h
=K
h
*
This gives a negative answer to a problem asked independently by Wu and Yang. Furthermore, some related topics are also discussed. 相似文献
112.
Piotr Gwiazda 《Mathematical Methods in the Applied Sciences》2005,28(18):2201-2223
This paper concerns measure‐valued solutions for the two‐dimensional granular avalanche flow model introduced by Savage and Hutter. The system is similar to the isentropic compressible Euler equations, except for a Coulomb–Mohr friction law in the source term. We will partially follow the study of measure‐valued solutions given by DiPerna and Majda. However, due to the multi‐valued nature of the friction law, new more sensitive measures must be introduced. The main idea is to consider the class of x‐dependent maximal monotone graphs of non‐single‐valued operators and their relation with 1‐Lipschitz, Carathéodory functions. This relation allows to introduce generalized Young measures for x‐dependent maximal monotone graph. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
113.
设$\varphi$为群${\rm Aut}(N)$的同态,记$H_\varphi\times N$为群$N$借助于群$H$的半直积.设$G$为有限不可解群,本文证明: 若$G$中最高阶元素个数为40, 则$G$同构于下列群之一:(1)~$Z_{4\varphi}\times A_5$,\,${\rm ker}\varphi=Z_2$; (2)~$D_{8\varphi}\times A_5,\,{\rm ker}\varphi=Z_2\times Z_2$; (3)~$G/N=S_5$, $N=Z(G)=Z_2$; (4)~$G/N=S_5$, $N=Z_2\times Z_2,\,N\cap Z(G)=Z_2$. 相似文献
114.
求出了(n-3)-filiform李代数的极大环面,并证明了(n-3)-filiform李代数是可完备化的. 相似文献
115.
本文讨论了δtuε-divA(x/ε,↓Δuε)-kuε=f的整体吸引子A^ε与其均匀化后的方程δtu-divA(↓Δu)-ku=f的整体吸引子A^0之间的关系,并给出了A^ε与A^0之间距离的估计。 相似文献
116.
In this paper, we study a second order variational problem for locally convex hypersurfaces, which is the affine invariant analogue of the classical Plateau problem for minimal surfaces. We prove existence, regularity and uniqueness results for hypersurfaces maximizing affine area under appropriate boundary conditions.
117.
非紧超凸度量空间中的一个新的极大元定理及其对抽象经济的应用 总被引:2,自引:0,他引:2
在非紧超凸度量空间中建立了一个新的极大元定理.作为应用,获得了连续选择及其不动点定理和一个Browder-Fan不动点定理.最后,新建了非紧超凸度量空间中的定性对策和抽象经济的平衡点存在定理. 相似文献
118.
Finite groups of Lie type form the greater part of known finite simple groups. An important class of subgroups of finite groups
of Lie type are so-called reductive subgroups of maximal rank. These arise naturally as Levi factors of parabolic groups and
as centralizers of semisimple elements, and also as subgroups with maximal tori. Moreover, reductive groups of maximal rank
play an important part in inductive studies of subgroup structure of finite groups of Lie type. Yet a number of vital questions
dealing in the internal structure of such subgroups are still not settled. In particular, we know which quasisimple groups
may appear as central multipliers in the semisimple part of any reductive group of maximal rank, but we do not know how normalizers
of those quasisimple groups are structured. The present paper is devoted to tackling this problem.
Supported by RFBR (grant No. 05-01-00797) and by SB RAS (Young Researchers Support grant No. 29 and Integration project No.
2006.1.2).
__________
Translated from Algebra i Logika, Vol. 47, No. 1, pp. 3–30, January–February, 2008. 相似文献
119.
Bailin Hao 《Journal of statistical physics》2005,121(5-6):749-757
This is a brief review on critical slowing down near the Feigenbaum period-doubling bifurcation points and its consequences.
The slowing down of numerical convergence leads to an “operational” fractal dimension D=2/3 at a finite order bifurcation point. There is a cross-over to D
0=0.538... when the order goes to infinity, i.e., to the Feigenbaum accumulation point. The problem of whether there exists
a “super-scaling” for the dimension spectrum D
q
W
that does not depend on the primitive word W underlying the period-n-tupling sequence seems to remain open 相似文献
120.
Alexander V. Rezounenko 《Mathematical Methods in the Applied Sciences》2008,31(13):1569-1585
A new class of nonlinear partial differential equations with distributed in space and time state‐dependent delay is investigated. We find appropriate assumptions on the kernel function which represents the state‐dependent delay and discuss advantages of this class. Local and long‐time asymptotic properties, including the existence of global attractor and a principle of linearized stability, are studied. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献