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991.
华宇明 《应用数学与计算数学学报》1994,8(1):77-85
考虑函数f(x)=sum from i=1 to ∞(?)~(-1)φ((?) θ_n)和w(x)=sum from n=1 to ∞(?)φ_(?)((?)x θ_(?)),式中0<α<(?)是任意实数,在一定条件下,估计了函数f图象的Hausdorff维数的下界,并求得了w函数图象的Box维数和Packing维数。 相似文献
992.
Starting from Monge’s mass transportation problem we review the role Monge properties play in optimization. In particular we discuss transportation problems whose cost functions fulfill a Monge property, Monge sequences, algebraic Monge properties, the recognition of permuted Monge arrays and multidimensional Monge arrays and the connections between Monge properties and discrete convexity. Finally we discuss Prékopa’s recent approach using Monge arrays in bounding multivariate probability distribution functions. 相似文献
993.
I. Moret 《Numerical Linear Algebra with Applications》2007,14(5):445-457
The paper deals with the application of the restricted‐denominator rational Krylov method, recently discussed in (BIT 2004; 44 (3):595–615; SIAM J. Sci. Comput. 2005; 27 :1438–1457), to the computation of the action of the so‐called φ‐functions, which play a fundamental role in several modern exponential integrators. The analysis here presented is devoted in particular to the construction of error estimates of easy practical use. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
994.
N Fang 《Journal of the mechanics and physics of solids》2003,51(4):715-742
The effect of tool edge roundness attracts growing attention from the international machining research community due to ever accelerating applications of precision, super-precision, micro-, and nano-machining technologies in a wide variety of modern industries. A new slip-line model for machining with a rounded-edge tool and its associated hodograph are proposed in this paper. The model consists of 27 slip-line sub-regions, each sub-region having its own physical meaning. It is demonstrated that the model simultaneously takes into account nine effects, such as the shear-zone effect and the size effect, which commonly occur in machining. Eight groups of machining parameters, such as the ploughing (parasitic or non-cutting) force and the chip up-curl radius, can be simultaneously predicted from the model. Furthermore, the model incorporates eight slip-line models previously developed for machining during the last six decades as special cases. An additional special case that involves a parallel-sided shear zone can also be derived from the new model. A mathematical formulation of the model is established based on Dewhurst and Collins's (1973) matrix technique for numerically solving slip-line problems. A purely analytical equation is proposed to predict the thickness of the primary shear zone. This equation is also employed to predict the shear strain-rate in the primary shear zone. 相似文献
995.
Roberto Artuso Giampaolo Cristadoro 《Communications in Nonlinear Science & Numerical Simulation》2003,8(3-4):137
We review how transport properties for chaotic dynamical systems may be studied through cycle expansions, and show how anomalies can be quantitatively described by hierarchical sequences of periodic orbits. 相似文献
996.
Nguyen Buong 《Computational Mathematics and Mathematical Physics》2007,47(10):1583-1588
The goal of this study is to analyze the Tikhonov regularization method as applied to a general nonlinear optimization problem
that has been previously reduced to an unconstrained optimization problem. The stability properties of the method are examined,
and its convergence is proved.
The text was submitted by the author in English. 相似文献
997.
Bilevel programming involves two optimization problems where the constraint region of the first-level problem is implicitly determined by another optimization problem. In this paper, we consider the case in which both objective functions are quasiconcave and the constraint region common to both levels is a polyhedron. First, it is proved that this problem is equivalent to minimizing a quasiconcave function over a feasible region comprised of connected faces of the polyhedron. Consequently, there is an extreme point of the polyhedron that solves the problem. Finally, it is shown that this model includes the most important case where the objective functions are ratios of concave and convex functions 相似文献
998.
M. A. Galdunts S. G. Rafayelyan 《Journal of Contemporary Mathematical Analysis (Armenian Academy of Sciences)》2007,42(5):241-253
The paper investigates the interpolation and basicity problem in Banach spaces of entire functions of exponential type in several variable. Some sufficient conditions for solvability of these problem and the explicit analytic form of the solutions are obtained. 相似文献
999.
Raimundas Vidunas Nico M. Temme 《Journal of Mathematical Analysis and Applications》2002,269(1):317-331
Computer algebra algorithms are developed for evaluating the coefficients in Airy-type asymptotic expansions that are obtained from integrals with a large parameter. The coefficients are defined from recursive schemes obtained from integration by parts. An application is given for the Weber parabolic cylinder function. 相似文献
1000.
设D是C中的单位圆盘及为[0,1)上的正规函数。对于0<P<∞,这样的函数用于定义一个带权为 ̄p(|z|)/(1-|z| ̄2)的Bergman空间A ̄p.本文刻画了A ̄p中函数之零点集的结构.作为应用,又给出了A ̄p中函数序列插值的条件。 相似文献