布朗运动的相遇问题

本文是[4]的继续,讨论BM(布朗运动,下同)的相遇问题。由[4],在R~d(d≥2)相遇的概率为0,故这里只讨论一维BM在相遇前后的行为。求出了二相互独立BM首碰时与首碰点的联合分布,二者首碰前的极大游程与极小游程的分布,极大游程、极小游程以及首碰点三者分布之间的一系列关系。另一方面,本文还从理论上解释了BM关于碰撞的不变性。最后对更一般的所谓广义相遇问题作了统一的处理。     

多元函数极限不存在的判定法则

求多元函数的极限,文[1]、文[2]给出多元函数未定型极限的定值法则,本文给出判定多元函数极限不存在的判定法则.     

关于极限定理的随机转移

<正> 许多作者([3]-[5])曾研究过随机变量序列的部分和极限定理的随机转移.D.J.Aldous在[1]中讨论了函数空间D[0,+∞)上一类较广泛的随机指标极限定理.本文考察有别于他们工作的一类函数型极限定理的随机转移;文中首先讨论函数空间D[0,1]上泛函正态极限定理的随机转移问题,接着讨论一些非正态随机极限定理.     

系统辨识中LS估计的渐近正态性的注记

文献[1]中,我们用有关鞅的中心极限定理,证明了系统辨识中LS估计的渐近正态性。然而[1]中的条件是苛刻的。本文利用Mcleish的相依变量的中心极限定理改进了[1]的结果。     

局部紧拓扑半群上概率测度卷积幂的若干极限定理

我们通过研究极限测度的不变性质，讨论了局部紧拓扑半群上概率测度卷积幂的若干极限性状．推广了[1]－[3]中的若干结果．     

高负荷情形多路到达,多服务台系统中负荷与等待时间的极限定理

对多路到达,多服务台系统,在服务强度 ρ≥1时,[3]和[5]在服务台完全相同的条件下,得到了负荷与等待时间的极限定理.本文用不同于[3]和[5]的方法,在服务台不一定完全相同这一般的条件下,得到了负荷,等待时间及嵌入过程的极限定理.     

高负荷情形多路到达,多服务台系统中负荷与等待时间的极限定理

对多路到达,多服务台系统,在服务强度 ρ≥1时,[3]和[5]在服务台完全相同的条件下,得到了负荷与等待时间的极限定理.本文用不同于[3]和[5]的方法,在服务台不一定完全相同这一般的条件下,得到了负荷,等待时间及嵌入过程的极限定理.     

数列{(1+1/n)~n}极限存在性的证明与e近似计算

<正> 数列{(1+1/n)~2}的极限是数学上最重要的极限之一,关于它的存在性的证明方法已有多种,参见文[1]、[2]、[3],本文提供这个极限存在性的两种证法,并且给出用常用对数的工具计算e的近似值及进行误差估计的初等方法。     

一个至少具有六个极限环的三次微分系统

关于平面三次微分系统的极限环的个数问题,文献[1]、[2]分别得到了在一个奇点的邻域内产生五个环的结果。本文给出了一个至少具有六个极限环的具体例子,从而说明三次微分系统极限环的最大个数不小于六。 考虑系统     

一类具有二阶细焦点的二次系统

文[2]已经证明,具有三阶细焦点的二次系统(叶彦谦形式)当n=0时不存在极限环。本文继续运用文[2]的方法,得到了具有二阶细焦点的二次系统当n=0时在二阶细焦点外围存在极限环的条件和不存在极限环的条件,同时证明这种系统在其他奇点外围不存在极限环。     

Whitworth runs on a circle

Summary Suppose different classes of items, for example, beads of different colours, are placed in a circle. Two probability models have been proposed, which lead to different distributions of runs, i.e. sequences of one colour. Barton and David [3] have called these Whitworth runs and Jablonski runs, and have tabulated the distributions for small samples. Asano [1] has extended the tabulations for Jablonski runs. In this paper, Whitworth runs are examined, particularly some approximations to the distributions which avoid extensive tabulations. Some potential uses of Whitworth runs are also pointed out.     

样条变差缩减算子迭代极限的一个简单证明

一、引言在[1]和[2]中,胡莹生、徐叔贤利用 Markov 链终极条件概率的有关结果,确定了一类变差缩减算子的迭代极限.本文采用作者在[3]中使用的技巧,利用多项式样条的若干基本知识,不但简单地得出了[1,2]的结果,并且给出了迭代收敛速度的估计.对于等距分划的三次样条,所给的误差估计在某种意义上是最好的.     

ALGORITHMS FOR IMPLEMENTATION OF GENERAL LIMIT REPRESENTATIONS OF GENERALIZED INVERSES

1. Introduction and PreliminariesThe set of all m x n comPlex matrices of rank r is denoted by cy". By I we denote anappropriate ideniity matrix. Also, n(A) denotes the trace of a square matriX A. By n(A) andN(A) are denoted the range and the null space of A, respectively Finally ad(A) and det(A)denote the adoint of the matris A and the determinant of A, respectivelyFOr any matrix A E crxn consider the following equations in X:(1) AXA=A, (2) XAX=X, (3) (AX)*=AX, (4) (XA)*=XAand…     

关于任意随机变量序列泛函的强极限定理

本文在k是固定的正整数，{fn}是R^k 1上的Borel可测函数列时，得到了任意随机变量序列{Xrn≥0}的泛函{fn(Xn-k,…,Xn)}的强极限定理，它是Chung的关于独立随机变量序列的强大数律的推广，作为推论，得到了k重非齐次马尔科夫链的一类强极限定理．     

Enforcing minimum run length in the cutting stock problem

Deckling, cutting stock or trim loss problems arise when small units are to be fitted into large ones. One aims to reduce stock usage and setups, then favors long runs, surplus over waste, similar loss per pattern and prompt delivery. One may also want to enforce exact solutions, with zero tolerance for surplus, or those with a narrow limit on pattern loss.Among secondary objectives, setups affect run length: on the average, fewer setups mean longer runs. Yet this relation is erratic. As setups decrease, some runs become longer, but others may stay as short as they are or become even shorter. We first show that this is so.We then examine the feasibility and the cost of making the shortest run longer in one-dimensional deckling problems. We show that conditional constraints do not formally enforce long runs, yet help to prove that they add at least one stock unit to an otherwise optimal plan. In turn, a relaxed stock constraint may improve runs, setups and surplus.     

ON THE CENTER OF GENERALIZED LIENARD SYSTEM

This paper discusses the local and global center of the generalized Lienard system, gives two theorems which extend and improve the relative results of [1]-[3]. Moreover the lemmas in this paper are also useful to the study for the oscillation, stability and the existence of limit cycles of the generalized Lienard system.     

Limit theorems for runs based on ‘small spacings’

A new concept of runs was proposed in the work of Eryilmaz and Stepanov (2008). A sequence of spacings forms a run if the lengths of these spacings do not exceed ε>0. In that paper, asymptotic properties of such spacings were investigated and statistical criteria proposed. In our present study, we maintain research on runs associated with these spacings. We derive limit theorems for the total number of runs, longest run and propose a statistical criterion.     

PROPERTIES OF CHARACTERISTIC FUNCTIONS AND EXISTENCE OF LIMIT CYCLES OF LIENARD''S EQUATION

In this paper, the author considers Lienard''s equation, studies the properties of so-called characteristic functions and gives three theorems which ensure that the equation has at least one limit cycle. The theorems generlize Filippov''s Theorem which is a repesentative result, Dragilev''s Theorem, Theorem 1 2 of [6], Theorem 9 of [8] and Theorems 1, 2 of [9] respectively.     

q元m序列非周期自相关函数的估计与M序列的分段线性化

序列的非周期自相关函数的估计,具有良好非周期自相关性的序列的构造,以及非线性M序列的相关性等方面已有的成果较少.著名的Barker序列当长度大于13时是否存在的问题尚未完全解决,L序列的非周期自相关函数的估计仅在长度较短时有一些数值计算结果,文献曾估计了一类二元序列非周期自相关函数的上界.最近,章照止巧妙地应用组合数学方法估计了状态两两不同的二元序列中一元的个数(在这基础     

LIMIT CYCLES OF A QUADRATIC HAMILTONIAN SYSTEM BY CUBIC PERTURBATIONS

In this paper,we are concerned with a cubic near-Hamiltonian system,whose unperturbed system is quadratic and has a symmetric homoclinic loop.By using the method developed in [12],we find that the system can have 4 limit cycles with 3 of them being near the homoclinic loop.Further,we give a condition under which there exist 4 limit cycles.