Effect of dependence on statistics for determination of change

Quite a number of test statistics and estimators for detection of a change in the mean of a series of independent observations were proposed and studied. The purpose of this paper is to examine the behaviour of these statistics if the observations are dependent, particularly, if they form a linear process.     

形式级数对称理论在高维可积模型中的应用

本文首先总结了文献[1─4]提出的形式级数对称理论在高维可积模型的研究中所取得的科研成果，然后，将其推广应用到（2 1）维的离散型Toda方程，得到了二族四个广义截断对称。     

Job Creation and Destruction over the Business Cycles and the Impact on Individual Job Flows in Denmark 1980-2001*

Summary: Job creation and destruction should be considered as key success or failure criteria of the economic policy. Job creation and destruction are both effects of economic policy, the degree of out- and in-sourcing, and the ability to create new ideas that can be transformed into jobs. Job creation and destruction are results of businesses attempting to maximize their economic outcome. One of the costs of this process is that employees have to move from destroyed jobs to created jobs. The development of this process probably depends on labor protection laws, habits, the educational system, and the whole UI-system. A flexible labor market ensures that scarce labor resources are used where they are most in demand. Thus, labor turnover is an essential factor in a well-functioning economy. This paper uses employer-employee data from the Danish registers of persons and workplaces to show where jobs have been destroyed and where they have been created over the last couple of business cycles. Jobs are in general destroyed and created simultaneously within each industry, but at the same time a major restructuring has taken place, so that jobs have been lost in Textile and Clothing, Manufacturing and the other “old industries”, while jobs have been created in Trade and Service industries. Out-sourcing has been one of the causes. This restructuring has caused a tremendous pressure on workers and their ability to find employment in expanding sectors. The paper shows how this has been accomplished. Especially, the paper shows what has happened to employees involved. Have they become unemployed, employed in the welfare sector or where? * First draft of this paper was presented at Deutsche Statistische Woche, Frankfurt, September 2004. Thanks to two referees for instructive comments. Financial support from The Danish Social Science Research Council through CCP is acknowledged.     

Optimal weighing designs with a string property

We consider the usual (spring balance) weighing design set-up with the design matrix having a string property meaning thereby that in every row of it, there is exactly one run of 1's (the rest of the elements being 0's). We have investigated some interesting features of such matrices and used them in deriving various optimality results.     

联吡啶型化合物的分子自组装

本文对近年来迅速发展起来的超分子化学作了简单介绍．着重讨论了联吡啶型化合物的分子自组装．     

Polynomially solvable cases of the constant rank unconstrained quadratic 0-1 programming problem

In this paper we consider the constant rank unconstrained quadratic 0-1 optimization problem, CR-QP01 for short. This problem consists in minimizing the quadratic function 〈x, Ax〉 + 〈c, x〉 over the set {0,1} ⁿ where c is a vector in ℝ ⁿ and A is a symmetric real n × n matrix of constant rank r. We first present a pseudo-polynomial algorithm for solving the problem CR-QP01, which is known to be NP-hard already for r = 1. We then derive two new classes of special cases of the CR-QP01 which can be solved in polynomial time. These classes result from further restrictions on the matrix A. Finally we compare our algorithm with the algorithm of Allemand et al. (2001) for the CR-QP01 with negative semidefinite A and extend the range of applicability of the latter algorithm. It turns out that neither of the two algorithms dominates the other with respect to the class of instances which can be solved in polynomial time.     

Robust kernel estimators for additive models with dependent observations

Robust nonparametric estimators for additive regression or autoregression models under an α-mixing condition are proposed. They are based on local M-estimators or local medians with kernel weights, and their asymptotic behaviour is studied. Moreover, diese local M-estimators achieve the same univariate rate of convergence as their linear relatives.     

中国共产党在中国近现代史上的历史功绩

胡锦涛总书记在七一讲话中科学界定了中国共产党在我国近现代史上的历史方位、历史地位、历史作用和历史贡献,以史证明了中国共产党的伟大、光荣和正确,揭示了中国共产党成功的历史资源,使人们对中国共产党的认同、信赖有了厚重的历史感。     

基于Pro/TOOLKIT的Pro/E参数化设计

Pro/E是应用非常广的一款软件,它提供了强大的三维造型、模拟分析等能力,并针对结构基本相同、只是尺寸有所差别的通用机械和标准零件等,Pro/E开发了Pro/TOOLKIT这一客户化开发工具包,以节省逐一进行建模所浪费的大量时间。文章利用VC++和Pro/TOOLKIT,通过动态链接库方式,完成源文件的编写、程序的编译和连接以及程序的注册和运行,详尽叙述了整个参数化的设计过程,并最后以1个实例进行了验证。     

绵粉一号及几个常用甘薯亲本的配合力分析

通过对当前几个甘薯亲本的配合力分析比较得出：以绵粉一号作亲本的后代块根三个主要性状（鲜苕重、薯干重、烘干率）的一般配合力（GCA）均高，特殊配合力（SCA）方差也大，后代材料平均烘干率32．51％，远远高于其它常用同类亲本。鲜苕与烘干率的负相关不显著，不失为一个好的甘薯育种亲本材料，为丰富我国甘薯品种的种质资源起到了重要的作用。