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61.
Vladimir P. Korzhik 《Discrete Mathematics》1998,190(1-3):149-162
The author has proposed methods of constructing index 2 and 3 current graphs generating triangular embeddings of graphs Kn−Km with unboundedly large m (as n increases). As a result, triangular embeddings of graphs of many families of graphs Kn−Km with unboundedly large m were constructed. The paper gives a survey of these results and a short explanation of the methods. 相似文献
62.
We consider some Sobolev-type spaces and obtain a necessary and sufficient condition for their embedding in a Lebesgue space. 相似文献
63.
Howel Tong 《应用数学学报(英文版)》2002,18(2):177-184
Abstract I reflect upon the development of nonlinear time series analysis since 1990 by focusing on five majorareas of development. These areas include the interface between nonlinear time series analysis and chaos,thenonparametric/semiparametric approach,nonlinear state space modelling,financial time series and nonlinearmodelling of panels of time series. 相似文献
64.
R. S. Ismagilov 《Mathematical Notes》1997,62(2):186-197
We present simple proofs of the possibility of embedding ultrametric spaces in Hilbert spaces. The main part of the paper
deals with ultrametric spaces that we call totally infinite spaces. Related Hilbert spaces, automorphisms of totally infinite
spaces, and the corresponding linear operators are considered.
Transplated fromMatematicheskie Zametki, Vol. 62, No. 2, pp. 223–237, August, 1997.
Translated by V. E. Nazaikinskii 相似文献
65.
For the eigenvalue problem—λΔu = q(x)u in IRd, with the weight function q changing sign, conditions are discussed for existence of eigenvalues with positive decaying eigenfunctions. 相似文献
66.
We prove a general embedding theorem for Sobolev spaces on open manifolds of bounded geometry and infer from this the module structure theorem. Thereafter we apply this to weighted Sobolev spaces. 相似文献
67.
Nathan Habegger 《Topology and its Applications》1984,17(2):131-143
For a 2n?m connected map from an n-dimensional complex to a m-dimensional manifold, an obstruction to embedding up to homotopy type is defined. The vanishing of this obstruction is a necessary and sufficient condition (in the 2n?m connected case, 2n?m ? 2, m?n ?3) to obtain an embedding up to homotopy type. In case the target manifold is Euclidean space, it is shown that the obstruction vanishes if and only if certain Thom operations are trivial. A classification theorem is given in the 2n?m+1 connected case. 相似文献
68.
We prove an existence result for topologically locally flat embeddings of 2-spheres in simply connected 4-manifolds. This topological result is deduced from a splitting theorem for pointed Hermitian modules over a cyclic group ring. A stability result for such modules is also proved. This applies to the isotopy classification of locally flat embeddings.Partially supported by the NSF. 相似文献
69.
70.
A (K4-e)-design on v+w points embeds a Steiner triple system (STS) if there is a subset of v points on which the graphs of the design induce the blocks of a STS. It is established that wv/3, and that when equality is met that such a minimum embedding of an STS(v) exists, except when v=15. 相似文献