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61.
We prove a Desch‐Schappacher type perturbation theorem for strongly continuous and locally equicontinuous one‐parameter semigroups which are defined on a sequentially complete locally convex space. 相似文献
62.
André Luiz Flores Trajano Pires da Nóbrega Neto 《Journal of Pure and Applied Algebra》2011,215(6):1440-1442
Let p be an odd prime. A family of (p−1)-dimensional over-lattices yielding new record packings for several values of p in the interval [149…3001] is presented. The result is obtained by modifying Craig’s construction and considering conveniently chosen Z-submodules of Q(ζ), where ζ is a primitive pth root of unity. For p≥59, it is shown that the center density of the (p−1)-dimensional lattice in the new family is at least twice the center density of the (p−1)-dimensional Craig lattice. 相似文献
63.
64.
Rachel Quinlan 《Linear algebra and its applications》2011,434(6):1580-2271
Let V be a vector space of dimension n over any field F. Extreme values for the possible dimension of a linear subspace of EndF(V) with a particular property are considered in two specific cases. It is shown that if E1 is a subspace of EndF(V) and there exists an endomorphism g of V, not in E1, such that for every hyperplane H of V some element of E1 agrees with g on H, then E1 has dimension at least . This answers a question that was posed by Szechtman in 2003. It is also shown that a linear subspace of Mn(F) in which no element possesses a non-zero eigenvalue in F may have dimension at most . The connection between these two properties, which arises from duality considerations, is discussed. 相似文献
65.
66.
Valeri Obukhovskii Pietro Zecca 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(8):2765-2777
We introduce the notion of a multivalued causal operator and consider an abstract Cauchy problem in a Banach space for various classes of functional inclusions with causal operators. The methods of the topological degree theory for condensing maps are applied to obtain local and global existence results for this problem and to study the continuous dependence of a solution set on initial data. As application we generalize some existence results for semilinear functional differential inclusions and Volterra integro-differential inclusions with delay. 相似文献
67.
Greg Markowsky 《Expositiones Mathematicae》2011,29(3):253-282
This paper details an investigation into Kepler’s Laws. Newton’s technique for deducing an inverse-square law from Kepler’s Laws is given a modern presentation, with necessary background material included. Kepler’s Laws are then deduced from the assumption of an inverse-square law. This is done in a geometric style, inspired by Newton’s work. Finally, a problem involving planetary orbits is stated and solved using the earlier results of the paper. 相似文献
68.
Bernd Süssmann 《Differential Geometry and its Applications》2011,29(1):1-6
In this paper the classical Banchoff-Pohl inequality, an isoperimetric inequality for nonsimple closed curves in the Euclidean plane, involving the square of the winding number, is sharpened for homothetic or Abresch-Langer solutions of curve shortening. For a larger class of curves and for rotationally symmetric curves, further isoperimetric inequalities containing the rotation number and the winding number, are presented. 相似文献
69.
70.
In this paper we obtain, for a class of plane curves, extensions of the well-known relation of inflection points, double points and bitangencies established by Fabricius-Bjerre for closed curves. 相似文献