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1.
王霞  周国标 《应用数学》2003,16(4):130-135
通过鞅论分析来给出遗传算法的收敛率 ,这种分析方法的优势在于它不依赖于染色体的编码形式如常用的二进制形式 ,也不依赖于转移矩阵及其特征值的分析 ,它只以概率来给出遗传算法的收敛率 ,在形式上更加简单明了 ,这是鞅分析优于其它分析如马尔可夫链分析的独特优势 .本文分别对在一定条件下收敛的杰出遗传算法和整体退火遗传算法给出了收敛率的概率形式o( 1- mNn · sNn)和o 1N +N0+( 2 - cN0n - mN0n)e(Δ-δ) /Tn .  相似文献   

2.
关于A-收敛     
设A={ai}(i=1)∞S_(e_1)~+,其中S(e1)+={x=(x(n))∈e1:‖x‖=1且x(n)≥0对任意的n∈N}.Banach空间X中的序列{x_n}称为A-收敛于x∈X是指对任意的ε〉0,→0当i→∞,其中A(ε)={n∈N:‖x_n-x‖≥ε}.这篇文章中,我们证明了该收敛可以用一个有限可加的概率测度加以刻画.我们对A-收敛与统计收敛的关系进行了讨论,证明了A-收敛为统计收敛完全取决于A的w~*-拓扑性质.  相似文献   

3.
设{Xi)i=1^∞是一维平稳序列,具有公共的未知密度f(x),在{Xi}i=1^∞是α-混合的条件下,给出了f(x)基于前礼个观测值{Xi}i=1^∞的最近邻密度估计的强相合收敛速度,当f(x)满足适当条件,收敛速度可达到0(n^-1/3(ln n)^4(1+p)/3)).  相似文献   

4.
当无穷积分∫0^ ∞f(x)dx收敛时,若f(x)在[0, ∞]上一致连续,或者知lim x→ ∞f(x)存在,那么都有lim x→ ∞f(x)=0。  相似文献   

5.
见到 2 0 0 2年的数学考研试卷 ,总的感觉是较为适中。从四套试卷的整卷看 ,都是较好的 ,但数三的幂级数题错了 !数三卷的二 ( 2 )题 :设幂级数 ∞n=1anxn与 ∞n=1bnxn的收敛半径分别为 53 和 13 ,则幂级数 ∞n=1a2nb2nxn的收敛半径为 ( A) 5;( B) 53 ;( C) 13 ;( D) 15。其参考答案是 ( A)。我们试举一个反例如下。例 1 设 ∞n=1anxn = ∞n=1( 35) nxn;而令 bn =3 n,当 n为奇数 ;bn =1 ,当 n为偶数 ,即 ∞n=1bnxn=3 x +x2 +3 3x3+x4 +… +3 2 k- 1x2 k- 1+x2 n +…  这样 , ∞n=1anxn 的收敛半径是 53 ;而 ∞n=1bnxn 的收敛半径是…  相似文献   

6.
从无穷积分∫+∞ a f(x)dx收敛与无穷远极限lim x→+∞f(x)=0之间的关系展开论述,研究在广义积分∫+∞ a f(x)dx收敛的前提下,无穷远极限lim x→+∞f(x)=0的一个充分条件.在此基础上,适当减弱条件得到该条件的推广形式,为更好的解决无穷远极限lim x→+∞f(x)=0的问题提供更一般的方法.  相似文献   

7.
胡长松 《应用数学》2004,17(4):568-574
设D是一致凸Banach空间X的非空闭凸子集 ,T∶D→D是渐近非扩张映射且kn ≥ 1 ,∑ ∞n =1(kn- 1 ) <∞ .设T的不动点集F(T) ≠ ,T是全连续的 (X满足Opial条件 ) ,{xn},{yn},{zn}由定义 2给出 ,如果 ∑∞n =1cn <∞ ,∑ ∞n =1c′n <∞ ,∑ ∞n =1c″n <∞ ,且下列条件之一满足 :(i)b″n ∈ [a ,b] ( 0 ,1 ) ;b′n ∈ [0 ,β];bn ∈[0 ,α],αβ β <1 ;(ii)b′n ∈ [a ,b] ( 0 ,1 ) ;b″n ∈ [a ,1 ];bn ∈ [0 ,b];(iii)bn ∈[a ,b] ( 0 ,1 ) ;b′n ∈ [a ,1 ],则 {xn},{yn},{zn}强收敛于T的不动点 .( {xn}弱收敛于T的不动点 ) .  相似文献   

8.
本文给出新Dirichlet级数Σ_(n=0)~∞a_ne~(λns)的收敛横坐标σ_c、一致收敛横坐标σ_u和绝对收敛横坐标σ_a的定义.通过指数λ_n和系数a_n的关系去估计三个横坐标,并补充证明两类Dirichlet级数Σ_(n=0)~∞a_ne~(λns)和Σ_(n=0)~∞a_ne~(-λns)的收敛条件是一致的.  相似文献   

9.
摘要设X_1,X_2,…为iid.,EX_1=0,0相似文献   

10.
根据无穷限反常积分∫a^+∞f(x)dx收敛的柯西准则和定积分的性质,讨论被积函数f(x)当x→∞时。的极限状态,并得出当无穷限反常积分∫a^+∞f(x)dx收敛且f(x)在[a,+∞)上连续,或者无穷限反常积分∫a^+∞f(x)dx绝对收敛时,存在数列{xn}∩[a,+∞]且xn→+∞(n→∞),使limn→∞xnf(xn)=0.  相似文献   

11.
As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years (2001-2005). The main topics are: convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.  相似文献   

12.
In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.  相似文献   

13.
In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p(R^n) into the Lebesgue space L^p with p 〈 1.  相似文献   

14.
15.
<正>August 10-14,2015Beijing,ChinaThe International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists  相似文献   

16.
<正>May 26,2014,Beijing Science is a human enterprise in the pursuit of knowledge.The scientific revolution that occurred in the 17th Century initiated the advances of modern science.The scientific knowledge system created by  相似文献   

17.
Let P(z)=∑↓j=0↑n ajx^j be a polynomial of degree n. In this paper we prove a more general result which interalia improves upon the bounds of a class of polynomials. We also prove a result which includes some extensions and generalizations of Enestrǒm-Kakeya theorem.  相似文献   

18.
Shanzhen  Lu  Lifang  Xu 《分析论及其应用》2004,20(3):215-230
In this paper, the authors study the boundedness of the operator [μΩ, b], the commutator generated by a function b ∈ Lipβ(Rn)(0 <β≤ 1) and the Marcinkiewicz integrals μΩ, on the classical Hardy spaces and the Herz-type Hardy spaces in the case Ω∈ Lipα(Sn-1)(0 <α≤ 1).  相似文献   

19.
Given the Laplace transform F(s) of a function f(t), we develop a new algorithm to find an approximation to f(t) by the use of the classical Jacobi polynomials. The main contribution of our work is the development of a new and very effective method to determine the coefficients in the finite series expansion that approximation f(t) in terms of Jacobi polynomials. Some numerical examples are illustrated.  相似文献   

20.
In applications it is useful to compute the local average empirical statistics on u. A very simple relation exists when of a function f(u) of an input u from the local averages are given by a Haar approximation. The question is to know if it holds for higher order approximation methods. To do so, it is necessary to use approximate product operators defined over linear approximation spaces. These products are characterized by a Strang and Fix like condition. An explicit construction of these product operators is exhibited for piecewise polynomial functions, using Hermite interpolation. The averaging relation which holds for the Haar approximation is then recovered when the product is defined by a two point Hermite interpolation.  相似文献   

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