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991.
In this paper we present a method for nondifferentiable optimization, based on smoothed functionals which preserve such useful properties of the original function as convexity and continuous differentiability. We show that smoothed functionals are convenient for implementation on computers. We also show how some earlier results in nondifferentiable optimization based on smoothing-out of kink points can be fitted into the framework of smoothed functionals. We obtain polynomial approximations of any order from smoothed functionals with kernels given by Beta distributions. Applications of smoothed functionals to optimization of min-max and other problems are also discussed. 相似文献
992.
993.
摘要:设{X,Xn,n≥1)为独立同分布的服从某连续分布F的随机变量序列,X^(1)=X1,X^(2),X^(3),…为其纪录值序列.令ψ(u)=F^-1(1-e^-u).其中F^-1是F的反函数.本文研究当ψ(u)=log^pu时Tn=∑k=1^nX^(k)=^dn∑k=1^nψ(Sn)的极限性质.解决了户为所有正整数时Tn的中心极限定理. 相似文献
994.
提出了任意域上鳞状循环因子矩阵 ,利用多项式环的理想的Go bner基的算法给出了任意域上鳞状循环因子矩阵的极小多项式和公共极小多项式的一种算法 .同时给出了这类矩阵逆矩阵的一种求法 .在有理数域或模素数剩余类域上 ,这一算法可由代数系统软件Co CoA4 .0实现 .数值例子说明了算法的有效性 相似文献
995.
P.G.L. Leach 《Journal of Mathematical Analysis and Applications》2006,322(1):288-297
The classical heat polynomials are polynomial solutions of the heat equation. We demonstrate the generation of such polynomials through the medium of the group theoretical properties of the equation. A generalised procedure for the generation of polynomial solutions is presented and this is extended to the construction of related polynomials. 相似文献
996.
Fatma Taşdelen Ali Olgun Gülen Başcanbaz-Tunca 《Proceedings Mathematical Sciences》2007,117(3):387-399
We introduce certain linear positive operators and study some approximation properties of these operators in the space of
functions, continuous on a compact set, of two variables. We also find the order of this approximation by using modulus of
continuity. Moreover we define an rth order generalization of these operators and observe its approximation properties. Furthermore, we study the convergence
of the linear positive operators in a weighted space of functions of two variables and find the rate of this convergence using
weighted modulus of continuity. 相似文献
997.
We use holding time methods to study the asymptotic behavior of pure birth processes with random transition rates. Both the normal and slow approaches to infinity are studied. Fluctuations are shown to obey the central limit theorem for almost all sample-transition rates. Our results are stronger, and our proofs simpler, then those of recently published studies. 相似文献
998.
We consider a two-machine open shop problem where the jobs have release dates and due dates, and where all single operations have unit processing times. The goal is to minimize the weighted number of late jobs. We derive a polynomial time algorithm for this problem, thereby answering an open question posed in a recent paper by Brucker et al.This research was supported by the Christian Doppler Laboratorium für Diskrete Optimierung. 相似文献
999.
We consider a many particle quantum system, in which each particle interacts only with its nearest neighbours. Provided that the energy per particle has an upper bound, we show, that the energy distribution of almost every product state becomes a Gaussian normal distribution in the limit of infinite number of particles. We indicate some possible applications. 相似文献
1000.
Proper Automorphisms of Universal Algebras 总被引:1,自引:1,他引:0