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931.
We obtain approximate solutions of Altarelli-Parisi equations beyond leading logarithmic approximation. Our results suggest
quantitative utility of higher order terms in the structure function analysis of deep inelastic scattering. 相似文献
932.
M. Oberguggenberger D. Scarpalézos 《Journal of Mathematical Analysis and Applications》2007,328(2):1321-1335
The definitions of positivity and positive definiteness are extended to generalized function algebras in coherence with the corresponding notions for distributions. Versions of Bochner's theorem for a positive definite Colombeau generalized function are given. 相似文献
933.
Interval arithmetic and Taylor's formula can be used to bound the slope of the cord of a univariate function at a given point. This leads in turn to bounding the values of the function itself. Computing such bounds for the function, its first and second derviatives, allows the determination of intervals in which this function cannot have a global minimum. Exploiting this information together with a simple branching rule yields an efficient algorithm for global minimization of univariate functions. Computational experience is reported.The first and second authors have been supported by FCAR (Fonds pour la Formation de Chercheurs et l'Aide à la Recherche) Grant 92EQ1048 and AFOSR Grant 90-0008 to Rutgers University. The first author has also been supported by NSERC (Natural Sciences and Engineering Research Council of Canada) Grant to HEC and NSERC Grant GP0105574. The second author has been supported by NSERC Grant GP0036426, FCAR Grant 90NC0305, and a NSF Visiting Professorship for Women in Science at Princeton University. Work of the third author was done in part while he was a graduate student at the Department of Mathematics, Rutgers University, New Brunswick, New Jersey, USA and during a visit to GERAD, June–August 1991. 相似文献
934.
Hitoshi Tanaka 《数学学报(英文版)》2002,18(3):447-454
Let K
δ, 0 < δ≪1, be the Kakeya maximal operator defined as the supremum of averages over tubes of the eccentricity δ. The (so-called)
Fefferman-Stein-type inequality: is shown, where C
d
and α
d
are constants depending only on the dimension d and w is a weight. The result contains the exponent (d−2)/2d which is smaller than the exponent (d−2)(d−1)/d(2d−3) obtained in [7].
Received October 8, 2001, Accepted February 28, 2002 相似文献
935.
Ngc-Minh Lê 《Computational Geometry》1997,8(6):279-298
We introduce the simple abstract Voronoi diagram in 3-space as an abstraction of the usual Voronoi diagram. We show that the 3-dimensional simple abstract Voronoi diagram of n sites can be computed in O(n2) expected time using O(n2) expected space by a randomized algorithm. The algorithm is based on the randomized incremental construction technique of Clarkson and Shor (1989). We apply the algorithm to some concrete types of such diagrams: power diagrams, diagrams under ellipsoid convex distance functions, and diagrams under the Hausdorff distance for sites that are parallel segments all having the same length. 相似文献
936.
N. B. Waite 《Journal of Optimization Theory and Applications》1994,80(3):537-549
We establish a smooth positive extension theorem: Given any closed subset of a finite-dimensional real Euclidean space, a function zero on the closed set can be extended to a function smooth on the whole space and positive on the complement of the closed set. This result was stimulated by nonlinear programming. We give several applications of this result to nonlinear programming.This paper is dedicated to the memory of Emily Sue Merkle Waite, Ph.D.The author wishes to thank W. Cunningham for suggesting the question about constraint qualifications, A. Karr for noticing the example of a Brownian motion sample path, R. Byrd and P. Hartman for discussions, and E. Waite for support and encouragement. 相似文献
937.
938.
An urn has balls of colors C1 and C2. It is replenished (R) by balls of both colors and then depleted by (D) the same number; this constitutes a cycle. When R = D, the system is closed and equilibrium will be reached after many cycles. The ultimate distribution is found only when the replenishment is the same for each color. Asymptotic normal and asymptotic binomial distributions arise when the parameters reach extreme values. For the multicolor urn an expression is given for the correlation between the number of balls of any two colors. 相似文献
939.
The topological part of the theory of the parameter-dependent Laplace integral is known to consist of two stages. At the first
stage, the integration contour is reduced to a sum of paths of steepest descent for some value of the parameter. At the second
stage, this decomposition (and hence the asymptotic expansion of the integral) is continued to all other parameter values.
In the present paper, the second stage is studied with the help of resurgent analysis techniques.
Translated fromMatematicheskie Zametki, Vol. 61, No. 2, pp. 278–296, February, 1997.
Translated by B. Yu. Sternin and V. E. Shatalov 相似文献
940.
We consider swapping of two records in a microdata set for the purpose of disclosure control. We give some necessary and sufficient
conditions that some observations can be swapped between two records under the restriction that a given set of marginals are
fixed. We also give an algorithm to find another record for swapping if one wants to swap out some observations from a particular
record. 相似文献