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991.
Aart Blokhuis Győrgy Kiss István Kovács Aleksander Malnič Dragan Marušič János Ruff 《组合设计杂志》2007,15(6):491-501
Semiovals which are contained in the union of three concurrent lines are studied. The notion of a strong semioval is introduced, and a complete classification of these objects in PG(2,p) and PG(2,p2), p an odd prime, is given. © 2007 Wiley Periodicals, Inc. J Combin Designs 15: 491–501, 2007 相似文献
992.
Xing-zhong YOU~ Guo-hua QIAN~ Wu-jie SHI~ 《中国科学A辑(英文版)》2007,50(10):1493-1500
We prove that if G is a finite group in which the elements of the same order outside the center are conjugate,then either G is abelian or G(?)S_3. 相似文献
993.
By introducing the conception "relativistic differential Galois group" for the second order polynomial systems, we establish the relation between the conformal relativistic differential Galois group and the subgroup of M(o)bius transformations, and prove that the system is integrable in the sense of Liouville if its conformal relativistic differential Galois group is solvable with a derived length at most 2. Some omissions on the structures of solvable subgroups of M(o)bius transformations at the first author's article published in this journal in 1996 are refreshed in this paper. 相似文献
994.
Boonlert Srihirun Sergey V. Meleshko Eckart Schulz 《Communications in Nonlinear Science & Numerical Simulation》2007,12(8):1379-1389
A new definition of an admitted Lie group of transformations for stochastic differential equations involving Brownian motion is presented. The transformation of the dependent variables involves time as well, and it is proved that Brownian motion is transformed to Brownian motion. Applications to a variety of stochastic differential equations are presented. 相似文献
995.
Fu-hai ZHU & Ke LIANG School of Mathematical Sciences LPMC Nankai University Tianjin China 《中国科学A辑(英文版)》2007,50(4):515-520
In this paper, we consider the unitary representations of equal rank exceptional groups of type E with a regular lambda-lowest K-type and classify those unitary representations with the nonzero Dirac cohomology. 相似文献
996.
The invariant sets and the solutions of the 1 2-dimensional generalized thin film equation are discussed. It is shown that there exists a class of solutions to the equations, which are invariant with respect to the set E0 = {u : ux = vxF(u), uy = vyF(u)}, where v is a smooth function of variables x, y and F is a smooth function of u. This extends the results of Galaktionov (2001) and for the l l-dimensional nonlinear evolution equations. 相似文献
997.
《Tetrahedron letters》2003,44(27):4961-4963
o-Formylation of electron-rich phenols is accomplished with dichloromethyl methyl ether and TiCl4. The reaction gives excellent yields, good regioselectivity, and does not leading to diformylation. 相似文献
998.
本文证明了:(1)Exchange环R的K0群的正向凸子群格同构于R的稳定余有限半本原理想格;(2)稳定有限、半本原的exchange环R是单的当且仅当它是K0-单的并且满足逼近弱s^*—可比性,推广了Goodearl,Ara等人的结果。 相似文献
999.
Let G be a finite group. Let p(G) denote the minimal degree of a faithful permutation representation ofG and let q(G) and c(G) denote the minimal degree of a faithful representation of G by quasi-permutation matrices over the rational and the complex numbers, respectively. Finally r(G) denotes the minimal degree of a faithful rational valued complex character of G. The purpose of this paper is to calculate p(G), q(G), c(G) and r(G) for the group SP(4,q).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
1000.
本文得到局部紧Vilenkin群上满足一定尺寸条件的一类次线性算子在加幂权Lebesgue空间的强有界和弱有界定理 相似文献