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71.
A computer search in the finite projective spaces PG(n, q) for the spectrum of possible sizes
k
of complete k-caps is done. Randomized greedy algorithms are applied. New upper bounds on the smallest size of a complete cap are given for many values of n
and q. Many new sizes of complete caps are obtained. 相似文献
72.
In this work, an inductive method to construct complete caps in affine spaces is provided. Using this tool, for odd and q odd, complete caps smaller than all already known ones are obtained. 相似文献
73.
Previous examples of non-type (D) maximal monotone operators were restricted to $\ell ^1$ , $L^1$ , and Banach spaces containing isometric copies of these spaces. This fact led to the conjecture that non-type (D) operators were restricted to this class of Banach spaces. We present a linear non-type (D) operator in $c_0$ . 相似文献
74.
75.
Maria Fernanda Elbert 《Proceedings of the American Mathematical Society》2000,128(5):1443-1450
We generalize Efimov's Theorem for graphs in Euclidean space using the scalar curvature, with an additional hypothesis on the second fundamental form. 相似文献
76.
In this paper, we consider shifted tridiagonal matrices. We prove that the standard algorithm to compute the LU factorization
in this situation is mixed forward-backward stable and, therefore, componentwise forward stable. Moreover, we give a formula
to compute the corresponding condition number in O(n) flops.
This research has been partially supported by Dirección General de Investigación (Ministerio de Ciencia y Tecnología) of Spain
through grants BFM2003-06335-C03-02 and MTM2006-06671 as well as by the Postdoctoral Fellowship EX2004-0658 provided by Ministerio
de Educación y Ciencia of Spain. 相似文献
77.
78.
We present an instrument based on Purkinje imaging that permits the objective measurement of the amount of scattering associated with the eye's anterior segment, avoiding the contribution from the retina. The experimental system records the fourth Purkinje image, and adequate processing is used to compute a parameter that quantifies the scattering. The method was first tested in an artificial eye and later in normal young eyes wearing customized contact lenses that induced different amounts of scatter. We were able to detect scattering increments, which indicates that this technique may be used as an objective tool to quantify the level of scattering in the anterior segment of the living human eye. The future use of this technique in clinical environments might help to estimate the level of corneal haze in eyes undergoing refractive surgery or/and scattering within the lens during cataract development. 相似文献
79.
Received June 4, 1996 / Revised version received November 19, 1997 Published online November 24, 1998 相似文献
80.
Fernanda Cipriano 《Communications in Mathematical Physics》1999,201(1):139-154
We construct surface type measures on the level sets for the renormalized energy, which is an invariant quantity for the two
dimensional periodic Euler flow, and prove the existence of weak solutions living on such level sets. Other classes of invariant
measures for the motion are also introduced.
Received: 3 December 1997 / Accepted: 20 August 1998 相似文献