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881.
一类局部定向完备集及其范畴的性质 总被引:4,自引:0,他引:4
本文给出了局部定向完备集的概念及其在此结构下的一种新的双小于关系,从而进一步给出了一种新的连续性概念,接着讨论了局部定向完备集,连续的局部定向完备集等对象的一些性质,最后考察了三种范畴的笛卡儿闭性,并证明了范畴LDCPO是范畴ALG的反射满子范畴. 相似文献
882.
883.
We study the relationship between the growth and decrease of the sum of the entire Dirichlet series of finite order (in the sense of Ritt) on arbitrary curves going to infinity. For a class of exponents having a regular distribution (in a certain sense), we obtain a test for the logarithm of the maximal term to be equivalent to the logarithm of the absolute value of the sum of the Dirichlet series on at least one unbounded sequence of points of the curve.__________Translated from Matematicheskie Zametki, vol. 78, no. 1, 2005, pp. 37–51.Original Russian Text Copyright © 2005 by A. M. Gaisin, I. D. Latypov. 相似文献
884.
In this article, the inverse problem of the differential inclusion theory is studied. For a given ε>0 and a continuous set valued map t→W(t), t∈[t0,θ], where W(t)⊂Rn is compact and convex for every t∈[t0,θ], it is required to define differential inclusion so that the Hausdorff distance between the attainable set of the differential inclusion at the time moment t with initial set (t0,W(t0)) and W(t) would be less than ε for every t∈[t0,θ]. 相似文献
885.
Xiang Fang 《Journal of Functional Analysis》2003,198(2):445-464
We define and study Hilbert polynomials for certain holomorphic Hilbert spaces. We obtain several estimates for these polynomials and their coefficients. Our estimates inspire us to investigate the connection between the leading coefficients of Hilbert polynomials for invariant subspaces of the symmetric Fock space and Arveson's curvature invariant for coinvariant subspaces. We are able to obtain some formulas relating the curvature invariant with other invariants. In particular, we prove that Arveson's version of the Gauss-Bonnet-Chern formula is true when the invariant subspaces are generated by any polynomials. 相似文献
886.
We study the lift-and-project procedures for solving combinatorial optimization problems, as described by Lovász and Schrijver, in the context of the stable set problem on graphs. We investigate how the procedures' performances change as we apply fundamental graph operations. We show that the odd subdivision of an edge and the subdivision of a star operations (as well as their common generalization, the stretching of a vertex operation) cannot decrease the N0-, N-, or N+-rank of the graph. We also provide graph classes (which contain the complete graphs) where these operations do not increase the N0- or the N-rank. Hence we obtain the ranks for these graphs, and we also present some graph-minor like characterizations for them. Despite these properties we give examples showing that in general most of these operations can increase these ranks. Finally, we provide improved bounds for N+-ranks of graphs in terms of the number of nodes in the graph and prove that the subdivision of an edge or cloning a vertex can increase the N+-rank of a graph.Research of these authors was supported in part by a PREA from Ontario, Canada and research grants from NSERC.Mathematics Subject Classification (2000): 0C10, 90C22, 90C27, 47D20 相似文献
887.
Masayuki Karato 《Mathematical Logic Quarterly》2005,51(3):305-312
Generalizing a result of Todor?evi?, we prove the existence of directed sets D, E such that D ? ??κλ and E ? ??κλ but D × E ≥ ??κλ in the Tukey ordering. As an application, we show that the tree property for directed sets introduced by Hinnion is not preserved under products. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
888.
Roland Hinnion 《Mathematical Logic Quarterly》1997,43(4):465-484
This is a study of the set of the Malitz-completions (which are a special case of Cauchy-completions) of a given infinite first-order structure, put in relation with properties of directed sets. 相似文献
889.
SUP-阿基米德T模合成算子模糊关系方程的求解 总被引:1,自引:0,他引:1
论文根据阿基米德 T模的一些特性 ,给出求解 SUP-阿基米德 T模合成算子模糊关系方程的方法 ,以及求解最大解和全体极小的解方法 . 相似文献
890.
设X(t)(t∈R )是一个d维非退化扩散过程.本文得到了比原有结果更一般的非退化扩散过程极性的充分条件,证明了对任意u∈Rd,紧集E(0, ∞),有若d=1,则对任意紧集F(?)R, 若d≥2,则对任意紧集E ∈(0, ∞), 其中B(Rd)为Rd上的Borel σ-代数,dim和Dim分别表示Hausdorff维数和Packing 维数. 相似文献