交换子

In this project we obtain a sufficient and necessary condition for a finite group G has a p-block with a normal p-subgroup D as a defect group, a necessary and sufficient condition for a group which is an extension of a nilpotent group by an abelian group has a p-block of defect zero.

本项目中我们给出了正规p-子群是有限群G的亏群的一个充要条件和幂零群被交换群扩张的群有亏零块的充要条件。

Next we obtain some group theoretic conditions for the existence of p-blocks with defect 0 in some special groups, for instance, in an extension group of a nilpotent group by a abelian group, in a p-nilpotent group, in a group with all subgroups of order p are conjugate, and so on.

其次我们给出了一些特殊群的亏零块存在的群论条件，如幂零群被交换群扩张的群，p—幂零群，p—阶子群均共轭的群等。

In terms of subshifts of finite type determined by an irreducible marrix, affine maps of compacted connected metric abelian group and continuous maps of tree, the two concepts of topologically ergodic map and topologically transitive map are identical.

指出对于由不可约方阵所决定的符号空间有限型子转移而言，或紧致交换群的仿射变换及树上连续自映射而言，拓扑遍历与拓扑可迁这两个概念是一致的。

In particular, when thereis an alternating group A_5 action on a Spin 4-manifold X, we obtain: If X is smooth Spin4-manifold with non-positive signature and b_1=0, denote k=-σ/16 and m=b_2~+,then 2k+3≤m if b_2~++b_2~+≠2b_2~+(Z/A_5) and b_2~+≠0,where and are subgroups of A_5 generated by the elements s=∈A_5and t=∈A_5 respectively.

特别地，在Spin 4-流形具有非交换群A_5作用时，我们得到了：若X为光滑的具有非正符号差的Spin 4-流形，b_1=0，令k=-σ／16，m=b_2~+，如果X上具有Spin交错群A_5作用，且满足b_2~++b_2~+≠2b_2~+(X／A_5)，b_2~+≠0，则2k+3≤m，其中和分别为s=∈A_5和t=∈A_5生成的A_5的子群。

Based on decomposition-coordination model of an electric power system,the general augmented Lagrange method and auxiliary problem principle are adopted to form iterative distributed transfer capability computation framework,in which the influence on the internal system exposed by external system is considered through exchanging the information of boun.

该方法通过分解-协调模型实现互联电网的解耦，采用增广拉格朗日法和辅助问题原理实现输电能力按地理分区，形成一个迭代形式的分布式输电能力计算框架，迭代中通过交换边界节点信息将互联外网信息反映到各分区的计算中，各地的子网络计算相对独立。

Let n ≥ 4 be a fixed integer, R be a unital commutative ring of characteristic not 2, and D_n be a D_n-type classical Lie algebra over R.

假设n是一个大于等于4的整数，R是特征非2的有单位元的交换环，D_n是环R上的D_n型李代数，N是D_n的一个极大幂零子代数。

Different from the sole-population evolution, the multi-population evolution partitioned the initial population into umpty sub-populations. Each sub-population evolved independently according to certain schema. In proper situation, the sub-populations would exchange information among themselves, to maintain the population diversity.

与单一种群进化不同的是，多种群进化将初始种群划分为若干子种群，各个子种群按照一定的模式独立进化，适当的时候在子种群之间交换信息，从而维持种群的多样性。

C.R.Miers has shown that the Lie triple derivation on a vN algebra M with no central abelian summands has the form D +λ, where D is an associative derivation and A is a linear map of M into its center which annihilates brackets of operators.

Miers证明了无交换部分的vN代数M上的三元Lie导子具有D+λ形式，其中D是M上的结合导子，λ是从M到它的中心Z上的线性映射且零化M中的括积。

A subgroup of a finite group G is called π-quasinormal in G if it permutes with every Sylow subgroup of G. A subgroup H of a group G is said to be c-supplemented in G if there exists a subgroup N of G such that G=HN and H∩N≤H=Core.

有限群G的一个子群称为在G中是π-拟正规的若它与G的每一个Sylow-子群是交换的。G的一个子群H称为在G中是c-可补的若存在G的子群N使得G=HN且H∩N≤H＝Core。

Aceoss operator was adhibited in host string, and variation operators were brought by host string and assistant string as well as different probability, and exchange 2 bits operator among operators according to situation.

在主串中引入交叉算子，主、副串以不同的概率发生变异算子，并随机交换其中两位。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。