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排序方式: 共有4539条查询结果,搜索用时 31 毫秒
941.
Strong convergence of pairwise NQD random sequences 总被引:1,自引:0,他引:1
Strong limit theory is one of the most important problems in probability theory. Some results on the convergence of pairwise NQD random sequences have been presented. This paper further analyzes the strong convergence of pairwise NQD sequences and generalizes partial results of Wu [Q.Y. Wu, Convergence properties of pairwise NQD random sequences, Acta Math. Sinica 45 (3) (2002) 617-624 (in Chinese)]. Since no general moment inequalities are given as so far, we avoid this problem and obtain a class of strong limit theorem for NQD sequences and some corresponding conclusions by use of truncation methods and generalized three series theorem, which are the supplements to the previous fruits. 相似文献
942.
We generalize some old and new results on the determination of jumps of a periodic, Lebesgue integrable function f at each point of discontinuity of first kind in terms of the partial sums of the conjugate series to the Fourier series of
f in [1], and in terms of the Abel-Poisson means in [2], to some more general linear operators which satisfy some certain conditions.
The linear operators in discussion include the Fejér means, de la Vallée-Poussin means, and Bernstein-Rogosinski sums.
Research also supported in part by NSF of China under grant number 10471130. 相似文献
943.
中性粒子在Ioffe阱中的经典运动 总被引:2,自引:0,他引:2
Ioffe阱因能对中性粒子实现稳定囚禁而成为一种倍受关注的磁阱。若只讨论阱中的近原点区域时,阱中的磁场可以呈现出一种简明的形式。磁矩μ反平行于磁场的中性粒子在阱中与磁场发生相互作用,借助相互作用势,可以获得粒子在阱中的经典运动方程。本文着重探究这种方程的近似求解方法。在一定的条件下,我们可以采用逐次近似的方法,使方程演化为我们熟悉的马丢方程的形式。若阱的参数设置使得马丢方程中λ>>q>0成立时,我们可以利用传统的WKBJ方法近似求解马丢方程。作为一种新的尝试,本文还采用傅立叶级数展开的办法来对马丢方程进行求解,从而得到中性粒子在阱中的经典运动规律。 相似文献
944.
Yilmaz Simsek 《Journal of Mathematical Analysis and Applications》2006,318(1):333-351
The main purpose of this paper is to define new generating functions. By applying the Mellin transformation formula to these generating functions, we define q-analogue of Riemann zeta function, q-analogue Hurwitz zeta function, q-analogue Dirichlet L-function and two-variable q-L-function. In particular, by using these generating functions, we will construct new generating functions which produce q-Dedekind type sums and q-Dedekind type sums attached to Dirichlet character. We also give the relations between these sums and Dedekind sums. Furthermore, by using *-product which is given in this paper, we will give the relation between Dedekind sums and q-L function as well. 相似文献
945.
Approximation of functions on the real axis by Féjer-type operators in the generalized Hölder metric
R. A. Lasuriya 《Mathematical Notes》2007,81(3-4):483-488
In this paper, we consider the orders of approximation of functions on the whole real axis by operators of Fejér type in the Banach space with the so-called generalized Hölder metric. 相似文献
946.
Recently an analytic algorithm for evaluating the Feigenbaum indices of one-dimensional maps was developed using a perturbative
expansion. We find that the use of Padé approximants in the resulting asymptotic series, significantly improves the technique. 相似文献
947.
Y. Endow 《Stochastic Processes and their Applications》1985,20(1):157-167
This paper deals with a Walsh-harmonizable dyadic stationary sequence {X(k): k=0, 1, 2,…} which is represented as , where ψk(λ) is the k-th Walsh function and ζ(λ) is a second-order process with orthogonal increments. One of the aims is to express the process {ζ(λ): λ?[0, 1)} in terms of the Walsh–Stieltjes series ∑ X(k)ψk(λ) of the original sequence X(k). In order to do this a Littlewood's Tauberian theorem for a series of random variables is introduced. A finite Walsh series expression of X(k) is derived by introducing an approximate Walsh series of X(k). Also derived is a strong law of large numbers for the dyadic stationary sequences. 相似文献
948.
S. Hagimura T. Saitoh Y. Yagihara 《Annals of the Institute of Statistical Mathematics》1988,40(3):419-438
Cement plant process is full of internal noise sources and feedback loops. Therefore, statistical approach is required to understand its dynamic characteristics. Time series analysis has been applied to some important subprocesses of a cement plant process. These are the vertical mill process, calcining process and clinker cooling process. Based on the AR models of these, a set of optimum controllers have been designed by modern control theory. Successful results of application are reported in this paper. A method of determining optimal production level is also discussed. 相似文献
949.
Wolfram Koepf 《The Ramanujan Journal》2007,13(1-3):103-129
The Bieberbach conjecture about the coefficients of univalent functions of the unit disk was formulated by Ludwig Bieberbach
in 1916 [4]. The conjecture states that the coefficients of univalent functions are majorized by those of the Koebe function
which maps the unit disk onto a radially slit plane.
The Bieberbach conjecture was quite a difficult problem, and it was surprisingly proved by Louis de Branges in 1984 [5] when
some experts were rather trying to disprove it. It turned out that an inequality of Askey and Gasper [2] about certain hypergeometric
functions played a crucial role in de Branges’ proof.
In this article I describe the historical development of the conjecture and the main ideas that led to the proof. The proof
of Lenard Weinstein (1991) [72] follows, and it is shown how the two proofs are interrelated.
Both proofs depend on polynomial systems that are directly related with the Koebe function. At this point algorithms of computer
algebra come into the play, and computer demonstrations are given that show how important parts of the proofs can be automated.
This article is dedicated to Dick Askey on occasion of his seventieth birthday.
2000 Mathematics Subject Classification Primary—30C50, 30C35, 30C45, 30C80, 33C20, 33C45, 33F10, 68W30 相似文献
950.
探讨了基于相空间重构的局部线性映射算法在非线性时间序列降噪技术中的应用,并给出了算法中主要参数的选取方法.实验结果表明,该算法的降噪效果明显优于传统的线性信号滤波技术.并且针对多数实测数据的原始动态模型未知的特点,提出通过计算降噪前后时序信号的关联维数作为评判降噪效果的工具,克服了已有方法中无法计算该类时序信号降噪水平的缺点. 相似文献