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51.
We study applications of divisibility properties of recurrence sequences to Tate’s theory of abelian varieties over finite
fields.
相似文献
52.
We study inventory systems with two demand classes (critical and non-critical), Poisson demand and backordering. We analyze dynamic rationing strategies where the number of items reserved for critical demand depends on the remaining time until the next order arrives. Different from results in the literature, we do not discretize demand but derive a set of formulae that determine the optimal rationing level for any possible value of the remaining time. Moreover, we show that the cost parameters can be captured in a single relevant dimension, which allows us to present the optimal rationing levels in charts and lookup tables that are easy to implement. Numerical examples illustrate that the optimal dynamic rationing strategy outperforms all static strategies with fixed rationing levels. 相似文献
53.
We prove that in a finite group of odd order, the number of irreducible quadratic characters is the number of quadratic conjugacy classes. 相似文献
54.
In this paper the main focus is on a stability concept for solutions of a linear complementarity problem. A solution of such
a problem is robust if it is stable against slight perturbations of the data of the problem. Relations are investigated between
the robustness, the nondegenerateness and the isolatedness of solutions. It turns out that an isolated nondegenerate solution
is robust and also that a robust nondegenerate solution is isolated. Since the class of linear complementarity problems with
only robust solutions or only nondegenerate solutions is not an open set, attention is paid to Garcia's classG
n
of linear complementarity problems. The nondegenerate problems inG
n
form an open set. 相似文献
55.
This paper studies the periodic feedback stabilization for a class of linear T -periodic evolution equations. Several equivalent conditions on the linear periodic feedback stabilization are obtained. These conditions are related to the following subjects: the attainable subspace of the controlled evolution equation under consideration; the unstable subspace (of the evolution equation with the null control) provided by the Kato projection; the Poincaré map associated with the evolution equation with the null control; and two unique continuation properties for the dual equations on different time horizons [0,T] and [0,n0T] (where n0 is the sum of algebraic multiplicities of distinct unstable eigenvalues of the Poincaré map). It is also proved that a T-periodic controlled evolution equation is linear T-periodic feedback stabilizable if and only if it is linear T-periodic feedback stabilizable with respect to a finite-dimensional subspace. Some applications to heat equations with time-periodic potentials are presented. 相似文献
56.
群类理论是在有限可解群研究工作的基础上发展起来的,但近年来对有限群论的许多方面都起到越来越大的作用.在考察群类性质时,注意到一个Fitting类(?)在可解群G中的(?)内射子具有Sylow子群所具有的某些性质,并且关于Sylow定理中(Sy13),证明了对于群的本原子群,成立更强的结论. 相似文献
57.
Maxim Kontsevich 《Compositio Mathematica》1999,115(1):115-127
We show that recently constructed invariants of 3-dimensional manifolds and of hyperkähler manifolds (L. Rozansky and E. witten) come from characteristic classes of foliations and from Gelfand-fuks cohomology. 相似文献
58.
I. E. Zverovich 《Mathematical Notes》2000,67(1):41-44
A graph is calledwell-covered if all maximal independent subsets in it have the same number of elements. LetI be an independent subset (possibly empty) in a graphG. The subgraph ofG obtained by erasing the setI together with its neighborhood is calledcostable. We present a characterization of the class of well-covered graphs in terms of the minimal set of prohibited costable subgraphs.
This characterization implies characterizations of some well-known subclasses of the class of well-covered graphs as well
as the existence of a polynomial algorithm for the recognition of well-covered graphs with bounded valences.
Translated fromMatematicheskie Zametki, Vol. 67, No. 1, pp. 52–56, January, 2000. 相似文献
59.
For quasianalytic Denjoy-Carleman differentiable function classes CQ where the weight sequence Q=(Qk) is log-convex, stable under derivations, of moderate growth and also an L-intersection (see (1.6)), we prove the following: The category of CQ-mappings is cartesian closed in the sense that CQ(E,CQ(F,G))≅CQ(E×F,G) for convenient vector spaces. Applications to manifolds of mappings are given: The group of CQ-diffeomorphisms is a regular CQ-Lie group but not better. 相似文献
60.
Hélène Esnault 《K-Theory》1992,6(1):45-56
On a smooth varietyX defined over a fieldK of characteristic zero, one defines characteristic classes of bundles with an integrableK-connection in a group lifting the Chow group, which map, whenK is the field of complex numbers andX is proper, to Cheeger-Simons' secondary analytic invariants, compatibly with the cycle map in the Deligne cohomology. 相似文献