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991.
本文研究所有子群皆交换或正规的有限群. 我们获得了非幂零的情形的一个特征刻画, 也给出了幂零情形的一些性质. 相似文献
992.
FENG Lianggui 《中国科学A辑(英文版)》2000,43(6)
For a commutative ring R, its related characterizations are given by investigating the structure and properties of H0R. Furthermore, by virtue of H0 structure, some important characterizations of CPF properties and connected properties on K0R are obtained from related rings. 相似文献
993.
M. R. DARAFSHEH 《数学学报(英文版)》2008,24(7):1117-1126
The author will prove that the group ^2Dp(3) can be uniquely determined by its order components, where p ≠ 2^m + 1 is a prime number, p ≥ 5. More precisely, if OC(G) denotes the set of order components of G, we will prove OC(G) = OC(^2Dp(3)) if and only if G is isomorphic to ^2Dp(3). A main consequence of our result is the validity of Thompson's conjecture for the groups under consideration. 相似文献
994.
Lianggui Feng 《中国科学A辑(英文版)》2000,43(6):568-573
For a commutative ringR, its related characterizations are given by investigating the structure and properties ofH
0
R. Furthermore, by virtue ofH
0 structure, some important characterizations of CPF properties and connected properties onK
0
R are obtained from related rings. 相似文献
995.
M. M. Lafisheva M. Kh. Shkhanukov-Lafishev 《Computational Mathematics and Mathematical Physics》2008,48(10):1875-1884
Locally-one-dimensional difference schemes for the fractional diffusion equation in multidimensional domains are considered. Stability and convergence of locally one-dimensional schemes for this equation are proved. 相似文献
996.
Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations 总被引:4,自引:0,他引:4
QU Chang-Zheng ZHANG Shun-Li 《理论物理通讯》2005,44(4):577-582
Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach. 相似文献
997.
Sébastien Falguières 《Journal of Functional Analysis》2008,254(9):2317-2328
We show that any compact group can be realized as the outer automorphism group of a factor of type II1. This has been proved in the abelian case by Ioana, Peterson and Popa [A. Ioana, J. Peterson, S. Popa, Amalgamated free products of w-rigid factors and calculation of their symmetry group, math.OA/0505589, Acta Math., in press] applying Popa's deformation/rigidity techniques to amalgamated free product von Neumann algebras. Our methods are a generalization of theirs. 相似文献
998.
Summary In this paper we consider experimental situations in which ν treatments are to be tested inb blocks whereb
i
blocks containk
i
experimental units,i=1,...,p, k
1<k
2<...<k
p
. The idea of a group divisible (GD) design is extended to that of a group divisible design with unequal block sizes (GDUB
design) and then a number of results concerning the E- and MV-optimality of GD designs are generalized to the case of GDUB
designs. 相似文献
999.
P.Y. Picard 《Journal of Mathematical Analysis and Applications》2008,337(1):360-385
We use the symmetry reduction method based on Lie group theory to obtain some exact solutions, the so-called invariant solutions, of the ideal magnetohydrodynamic equations in (3+1) dimensions. In particular, these equations are invariant under a Galilean-similitude Lie algebra for which the classification by conjugacy classes of r-dimensional subalgebras (1?r?4) was already known. We restrict our study to the three-dimensional Galilean-similitude subalgebras that give us systems composed of ordinary differential equations. Here, some examples of these solutions are presented with a brief physical interpretation. 相似文献
1000.