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本文给出了剩余交和一般剩余交的几个性质,主要讨论了剩余交的GCM性和在形变下的变化情况,并讨论了一般剩余交的GCM性,CM性和可光滑性等. 相似文献
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We study the connection between products of Sylow subgroups of a finite group G and the solvable residual of G. Let Π(𝒫) be a product of Sylow subgroups of G such that each prime divisor of |G| is represented exactly once in Π(𝒫). We prove that there exists a unique normal subgroup N of G which is minimal subject to the requirement Π(𝒫) N = G. Furthermore, N is perfect, and the product of all of these subgroups is the solvable residual of G. We also prove that the solvable residual of G is generated by all elements which arise from non-trivial factorizations of 1 G in such products of Sylow subgroups. 相似文献
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Jens-Peter M. Zemke 《PAMM》2008,8(1):10835-10836
We consider the extraction of approximate eigenpairs from a given Krylov subspace that are optimal, or at least quasi–optimal with respect to the normwise backward error. An algorithm based on Newton–Grassmannian optimization and a simple example are given; a useful graphical method of comparison with other extraction methods is briefly sketched. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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I. C. F. Ipsen 《BIT Numerical Mathematics》2000,40(3):524-535
Expressions and bounds are derived for the residual norm in GMRES. It is shown that the minimal residual norm is large as long as the Krylov basis is well-conditioned. For scaled Jordan blocks the minimal residual norm is expressed in terms of eigenvalues and departure from normality. For normal matrices the minimal residual norm is expressed in terms of products of relative eigenvalue differences. 相似文献
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We present a posteriori residual error estimators for the approximate time-dependent Stokes model Chorin–Temam (Chorin, Math. Comp. 23 (1969) 341–353) projection scheme using a conforming finite element discretization. We prove a global upper bound and local lower bounds for the error on the velocity field only. To cite this article: N. Kharrat, Z. Mghazli, C. R. Acad. Sci. Paris, Ser. I 340 (2005). 相似文献
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Belinda Trotta 《Algebra Universalis》2010,64(1-2):161-186
We say that a directed graph is pre-bipartite if its symmetric closure is bipartite. We will show that the class ${\mathcal{B}}$ of all pre-bipartite digraphs containing no cycles is a universal Horn class. Let ${\mathcal{U}}$ be a universal Horn class contained in ${\mathcal{B}}$ . We determine when it is possible to axiomatise, by first-order sentences, the class ${\mathcal{R}_{\rm CT}(\mathcal{U}_{\rm fin})}$ of compact topological digraphs that are topologically residually in the class of finite members of ${\mathcal{U}}$ . We show that if ${\mathcal{R}_{\rm CT}(\mathcal{U}_{\rm fin})}$ is axiomatisable by first-order sentences, then it is axiomatisable by universal Horn sentences. 相似文献
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Consider (X,F, μ,T) a Lebesgue probability space and measure preserving invertible map. We call this a dynamical system. For a subsetA ∈F. byT
A:A →A we mean the induced map,T
A(x)=TrA(x)(x) wherer
A(x)=min{i〉0:T
i(x) ∈A}. Such induced maps can be topologized by the natural metricD(A, A’) = μ(AΔA’) onF mod sets of measure zero. We discuss here ergodic properties ofT
A which are residual in this metric. The first theorem is due to Conze.Theorem 1 (Conze):For T ergodic, T
A is weakly mixing for a residual set of A.Theorem 2:For T ergodic, 0-entropy and loosely Bernoulli, T
A is rank-1, and rigid for a residual set of A.Theorem 3:For T ergodic, positive entropy and loosely Bernoulli, T
A is Bernoulli for a residual set of A.Theorem 4:For T ergodic of positive entropy, T
A is a K-automorphism for a residual set of A.
A strengthening of Theorem 1 asserts thatA can be chosen to lie inside a given factor algebra ofT. We also discuss even Kakutani equivalence analogues of Theorems 1–4. 相似文献
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Residual properties and almost equicontinuity 总被引:3,自引:0,他引:3
A propertyP of a compact dynamical system (X,f) is called a residual property if it is inherited by factors, almost one-to-one lifts and surjective inverse limits. Many
transitivity properties are residual. Weak disjointness from all propertyP systems is a residual property providedP is a residual property stronger than transitivity. Here two systems are weakly disjoint when their product is transitive.
Our main result says that for an almost equicontinuous system (X, f) with associated monothetic group Λ, (X, f) is weakly disjoint from allP systems iff the onlyP systems upon which Λ acts are trivial. We use this to prove that every monothetic group has an action which is weak mixing
and topologically ergodic. 相似文献
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研究Krylov子空间广义极小残余算法(GMRES(m))的基本理论,给出GMRES(m)算法透代求解所满足的代数方程组.深入探讨算法的收敛性与方程组系数矩阵的密切关系,提出一种改进GMRES(m)算法收敛性的新的预条件方法,并作出相关论证. 相似文献
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M. S. Akutin S. I. Sokolov M. L. Kerber I. O. Stal'nova A. K. Stal'nov S. I. Boborykina 《Mechanics of Composite Materials》1971,7(4):640-642
The variation of the axial and radial components of the residual stresses in fiber-reinforced polyethylene with distance from the fiber has been investigated. It is shown that, irrespective of the agent employed, coupling leads to an increase in stresses. The values obtained for the residual stresses are compared with the adhesion strength determined by the shearing method. The effect of a structure-forming agent on the residual stresses is investigated.Mendeleev Moscow Chemical Engineering Institute. Translated from Mekhanika Polimerov, No. 4, pp. 722–724, July–August, 1971. 相似文献