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731.
Huiling Li 《Journal of Combinatorial Theory, Series A》2009,116(1):1-11
Suppose that an almost simple group G acts line transitively on a finite linear space S. Let Gx be a point stabilizer in G and suppose that G has socle T, a simple group of Lie type. In this paper we show that if T∩Gx is a parabolic subgroup of T, then G is flag transitive on S. 相似文献
732.
J.W. Sanders 《Topology and its Applications》2009,156(11):1911-1918
The recovery of behaviour from its approximation over substructures is fraught with pathology. Here the extent is considered to which the behaviour of a continuous function on a locally compact Abelian group can be approximated by its behaviour on proper closed subgroups. Known results are summarised when the behaviour concerns integrability and the group is the circle; then boundedness and other limiting behaviour ‘at infinity’ are considered for more general groups. It is shown that if a continuous function is bounded on each proper closed subgroup of a connected locally compact Abelian group then it is bounded on the whole group. As befits this Festschrift, the techniques are predominantly topological. In passing we reflect on criteria for the difficult problem of identifying ‘substructures’ in Computer Science. 相似文献
733.
研究有限群特征标可扩张的情况是有限群表示论领域中一个有意义的问题.设G为有限群,用Irr(G)表示G的所有不可约复特征标构成的集合.设N(?)G,θ∈Irr(N)且θ是G-不变.如果(|G/N|,o(θ)θ(1))=1,则[1]中的推论8.16说明了此时υ到G有唯一的扩张χ,且o(χ)=o(θ).此结论启发了我们可以从特征标的行列式阶的角度来思考特征标扩张的情形.本文将利用有限群Brauer特征标的行列式阶,着重考虑Brauer特征标的可扩张情形.另外我们也得到了一个关于Brauer特征标次数的结论. 相似文献
734.
黄琼 《纯粹数学与应用数学》2016,32(5):546-550
通过Sylow子群的极大子群和次正规性,利用极小阶反例的方法,得出群p-幂零性和超可解性的结论.本文的创新改进之处在于结合Sylow子群的极大子群和次正规性,研究p-幂零性和超可解性的相关结论. 相似文献
735.
In the status forecasting problem, classification models such as logistic regression with input variables such as physiological, diagnostic, and treatment variables are typical ways of modeling. However, the parameter value and model performance differ among individuals with different baseline information. To cope with these difficulties, a subgroup analysis is conducted, in which models’ ANOVA and rpart are proposed to explore the influence of baseline information on the parameters and model performance. The results show that the logistic regression model achieves satisfactory performance, which is generally higher than 0.95 in AUC and around 0.9 in F1 and balanced accuracy. The subgroup analysis presents the prior parameter values for monitoring variables including SpO, milrinone, non-opioid analgesics and dobutamine. The proposed method can be used to explore variables that are and are not medically related to the baseline variables. 相似文献
736.
Nikolaos Panagiotis Souris 《Mathematische Nachrichten》2023,296(6):2609-2625
We study the geodesic equation for compact Lie groups G and homogeneous spaces , and we prove that the geodesics are orbits of products of one-parameter subgroups of G, provided that a simple algebraic condition for the Riemannian metric is satisfied. For the group , we relate this type of geodesics to the free motion of a symmetric top. Moreover, by using series of Lie subgroups of G, we construct a wealth of metrics having the aforementioned type of geodesics. 相似文献
737.
738.
For a positive integer N, let be the modular curve over and its Jacobian variety. We prove that the rational cuspidal subgroup of is equal to the rational cuspidal divisor class group of when for any prime p and any squarefree integer M. To achieve this, we show that all modular units on can be written as products of certain functions , which are constructed from generalized Dedekind eta functions. Also, we determine the necessary and sufficient conditions for such products to be modular units on under a mild assumption. 相似文献
739.
本文研究了((∈),(∈)V(q)(λ,μ))-模糊正规子群的一些新的性质.利用反扩张原理获得了它的满同态像与同态原像的相关结果,丰富了文献[1]中有关((∈),(∈)V(q)(λ,μ))-模糊正规子群的研究结果. 相似文献
740.
设G为有限p-可解群,其中p为|G|的奇素因子.若P为G的Sylow p-子群且最小生成系含d个元素.考虑集合M_d(P)={P_1,…,P_d},其中P_1,…,P_d是P的极大子群且满足(?)P_i=φ(P).证明了若M_d(P)中每个元在G中是S-拟正规嵌入的,则G为p-超可解群.作为应用,还得到了一些进一步的结论. 相似文献