Public Attitudes Toward Nanotechnology

Data from 3909 respondents to an Internet survey questionnaire provide the first insights into public perceptions of nanotechnology. Quantitative analysis of statistics about agreement and disagreement with two statements, one positive and the other negative, reveals high levels of enthusiasm for the potential benefits of nanotechnology and little concern about possible dangers. The respondents mentally connect nanotechnology with the space program, nuclear power, and cloning research, but rate it more favorably. In contrast, they do not associate nanotechnology with pseudoscience, despite its imaginative exploitation by science fiction writers. Qualitative analysis of written comments from 598 respondents indicates that many ideas about the value of nanotechnology have entered popular culture, and it provides material for an additional 108 questionnaire items that can be used in future surveys on the topic. The findings of this exploratory study can serve as benchmarks against which to compare results of future research on the evolving status of nanotechnology in society.     

用白炽灯作光源测量普朗克常量--第36届国际奥林匹克物理竞赛实验题分析

介绍了第36届国际奥林匹克物理竞赛“用白炽灯测量普朗克常量”实验,该题利用白炽灯作为辐射源并配合波长滤波器、减光板以及光敏电阻等装置,测量普朗克常量.文章对该实验进行了分析并给出解答.     

Statistical physics, optimization and source coding

The combinatorial problem of satisfying a given set of constraints that depend on N discrete variables is a fundamental one in optimization and coding theory. Even for instances of randomly generated problems, the question “does there exist an assignment to the variables that satisfies all constraints?” may become extraordinarily difficult to solve in some range of parameters where a glass phase sets in. We shall provide a brief review of the recent advances in the statistical mechanics approach to these satisfiability problems and show how the analytic results have helped to design a new class of message-passing algorithms — the survey propagation (SP) algorithms — that can efficiently solve some combinatorial problems considered intractable. As an application, we discuss how the packing properties of clusters of solutions in randomly generated satisfiability problems can be exploited in the design of simple lossy data compression algorithms.     

双辅助信息敏感性问题问卷调查技术

对于敏感性问题调查,已有多种随机化策略.提出一类方便、实用的双辅助信息间接问卷调查方法,讨论了估计量及其方差以及精度与保护度之间的关系.通过比较得出,在相同的保护度下,随机化方法与问卷方法在精度上各有得益.     

抽样调查中多个指标值的同时估计

本文在ＥＶ（Ｅｒｏｒ ｉｎ Ｖａｒｉａｂｌｅｓ）超总体模型下讨论有限总体两个指标值的同时估计问题，证明了样本均值作为整体均值的估计在均方差阵最小的意义下是最优的．     

抽样调查的设计与分析(Ⅱ)

本文讨论抽样调查实践中有关设计和数据分析中的若干问题．第二部分主要涉及数据处理与统计分析问题．     

Une ambition éditoriale “universelle et confraternelle” : le bulletin bibliographique de L'Enseignement mathématique (1899–1920)

In 1899 Henri Fehr and Charles Laisant founded L'Enseignement mathématique (EM) with the ambition to involve teachers in the then-growing internationalization movement of mathematics. To this purpose, their editorial project gave an important place to a bibliographical bulletin reviewing periodicals which could be of interest for the world of mathematical education. This article is dedicated to the study of this bulletin, from its creation to the 1920s, and to the initiatives and choices that Laisant and Fehr made to carry out this internationalist editorial ambition, as well as to the limits and constraints of their project. During that time, many bibliographical initiatives for periodicals developed in the mathematical press, which can be considered as a first form of interaction between journals. Our study will concern initially the year 1899 and this interaction in which EM took part, dealing at first with the bulletin of EM, then, secondly, with the confrontation between bibliographical sections of other journals. Lastly, considering the first thirty years of the 20th century, we will study the different dynamics at work in the world of mathematical periodicals which the EM serves to depict.     

The school bus routing problem: A review

This paper aims to provide a comprehensive review of the school bus routing problem (SBRP). SBRP seeks to plan an efficient schedule for a fleet of school buses where each bus picks up students from various bus stops and delivers them to their designated schools while satisfying various constraints such as the maximum capacity of a bus, the maximum riding time of a student in a bus, and the time window of a school. This class of problem consists of different sub-problems involving data preparation, bus stop selection, bus route generation, school bell time adjustment, and bus scheduling. In this paper, the various assumptions, constraints, and solution methods used in the literature on SBRP are summarized. A list of issues requiring further research is also presented.     

基于Markov Chain Monte Carlo模型对医院出院病人调查表数据缺失的填补与分析

目的对医院出院病人调查表普遍存在的数据缺失进行填补与分析,以保证统计调查表的质量,为医院以及上级卫生部门了解现状,进行预策和决策提供技术支持和质量保证。方法运用SAS9.1,采用多重填补方法Markov Chain Monte Carlo(MCMC)模型对缺失数据进行多次填补并综合分析。结果MCMC填补10次的结果最优。结论(Multiple Imputation)MI方法在解决医院出院病人调查表数据缺失时有优势,发挥空间较大,且填补效率较高。     

空间站快速充电事件的机理研究

空间站等大型航天器由于采用高压太阳电池阵而引发的 带电问题成为近年来航天器带电研究领域的热点问题. 近年来观测到国际空间站(ISS)在出地影瞬间产生的"快速带电"事件 (也称"异常带电") , 再度引起了对低轨道航天器充电效应的深入研究. "快速带电"事件的特征为, 集中出现在出地影的瞬间, 在几秒内快速上升到较高电位(30—70 V), 然后在几十秒时间内缓慢衰降, 相对高压电池阵本身引起的结构体带电(称为"正常带电", 一般在30 V以下)严重得多. 目前国际上对"快速带电"的研究尚不充分. 本文在Furguson等人机理研究工作的基础上, 首次建立了描述"快速带电"事件的物理模型, 定量揭示了其充电过程的主要机理. 根据该模型对国际空间站的"快速带电"进行计算, 结果与观测到的典型充电脉冲符合, 模型预测的快速带电事件的统计规律也与观测结果基本一致. 关键词： 表面充电 等离子体 空间站 高压太阳电池阵