一个抛物型方程逆问题的Fourier和小波正则化方法

考虑非标准的一维逆热传导方程的定解问题。问题是不适定性的,即g(t)微小扰动会引起解的很大误差。通过Fourier方法,舍去g(t)的高频成分来正则化问题并给出了误差估计;利用M eyer小波在频域中的紧支撑性滤除g(t)的高频成分并结合G alerk in方法建立了正则化方法,给出了误差估计;对上述两种方法给出了数值实验并进行了比较和讨论。     

基因工程技术的应用现状

基因工程是通过DNA重组技术,获得具有特殊生物遗传性状和功能的遗传工程生物体。基因工程技术广泛应用于农业、医学,食品工业等。但是这种人为改变生物体遗传特性的生物技术是否能安全地被利用,从而更好地造福人类呢?本文就基因工程的应用现状和存在问题作一综合阐述。     

Has It Really Been Demonstrated That Most Genomic Research Findings Are False?

In a widely cited article, Ioannidis argued that most published research findings are false; particularly discovery research involving massive testing, genomics being a typical example. However, his argument ignores adjustment for multiple testing and thus should be taken with a large grain of salt. This is a potential example for statistics courses that concentrate on problem formulation.     

The Dynamic Newsvendor Model with Correlated Demand

The classic newsvendor model was developed under the assumption that period‐to‐period demand is independent over time. In real‐life applications, the notion of independent demand is often challenged. In this article, we examine the newsvendor model in the presence of correlated demands. Specifically under a stationary AR(1) demand, we study the performance of the traditional newsvendor implementation versus a dynamic forecast‐based implementation. We demonstrate theoretically that implementing a minimum mean square error (MSE) forecast model will always have improved performance relative to the traditional implementation in terms of cost savings. In light of the widespread usage of all‐purpose models like the moving‐average method and exponential smoothing method, we compare the performance of these popular alternative forecasting methods against both the MSE‐optimal implementation and the traditional newsvendor implementation. If only alternative forecasting methods are being considered, we find that under certain conditions it is best to ignore the correlation and opt out of forecasting and to simply implement the traditional newsvendor model.      

Exact solutions to the Behrens–Fisher Problem: Asymptotically optimal and finite sample efficient choice among

The problem of testing the equality of two normal means when variances are not known is called the Behrens–Fisher Problem. This problem has three known exact solutions, due, respectively, to Chapman, to Prokof’yev and Shishkin, and to Dudewicz and Ahmed. Each procedure has level alpha and power beta when the means differ by a given amount delta, both set by the experimenter. No single-sample statistical procedures can make this guarantee. The most recent of the three procedures, that of Dudewicz and Ahmed, is asymptotically optimal. We review the procedures, and then compare them with respect to both asymptotic efficiency and also (using simulation) in finite samples. Of these exact procedures, based on finite-sample comparisons the Dudewicz–Ahmed procedure is recommended for practical use.     

试析对日民间索赔诉讼面临的主要问题

通过严密的历史分析和深入的法理探讨,说明日方的顽固态度、法律障碍、原告困境以及制约日本的手段有限是对日民间索赔面临的四个主要问题,也是对日民间索赔举步维艰的关键所在。因此,必须有针对性地寻找新的出路,以利改变在索赔问题上“义愤多于办法”的不利局面。     

关于中国古代科学与技术若干问题的哲学反思

首先,"李约瑟难题"中从未提及中国古代科技自某时期就衰落下去,而是说与西方国家相比没有15世纪之前的发展势头;其次,不论在何种意义下,"李约瑟难题"都是成立的。它有两部分组成,彼此呈并列关系,没有逻辑上的必然关系,因此,解答"李约瑟难题"非同一般命题。从另一视角看,近代科学技术未能在中国产生其根源在中国历史发展的关键时期,生产力比较低下的具有游牧特点的少数民族占据中原并统治全国;其次是农民起义造成的改朝换代。在"后李约瑟时代"国人应追寻中国科学技术发展的条件和规律,去超越"李约瑟时代"。     

Individual and organizational strategies for coping with organizational change

Abstract

During times of significant change to organizations in strategies and structures, employees can experience high levels of stress as their jobs, areas of responsibility and roles also change. Yet research is curiously silent about how people react to organizational change, especially towards promoting healthy responses to change. As a first step to outlining areas for future research this paper considers a range of individual and organizational strategies that may be effective in reducing employee stress and related problems. Prior to the implementation of these strategies, however, organizations must empower employees to adopt the role of change agent and encourage them to take action to solve the problems that stress them. At the individual level, employees can respond to the stress created by organizational change by using problem- and emotion-focused strategies. Also important in coping with change are the personal resources of employees, including a sense of hardiness, beliefs about having control over their work environment, and the availability of social supports within and outside the organization. Although few organizations fully acknowledge their role in helping employees cope with change, there are a number of initiatives that organizations can pursue. Several strategies are discussed in relation to communication, leadership, job-related tasks and stress management programmes.     

校外托管机构服务状况的调查研究——以N省S市F区为例

近年来,以校外辅导为主的托管机构纷纷涌现,名目繁多、鱼龙混杂,家长、学生、学校在取舍之间往往感到无所适从.笔者调查发现,校外托管机构大多建在小学附近的居民区,普遍存在着缺乏管理与规范,硬件设施较差,服务人员缺乏相关资格证等问题.笔者认为应从政府规范、责任主体、专业定位、亲子关系等方面着手,完善校外托管机构服务与管理.     

中英“香港问题”和香港回归的起步

香港被英国掠走之后,中国人就开始了让香港回归祖国的种种努力,但均以失败告终。建国后相当长一个时期,中共中央和中国政府对于香港问题的基本政策是“暂时维持现状不变”、对香港“长期打算、充分利用”。当收复香港的条件渐趋成熟的时候,邓小平“一国两制”解决台湾问题的新思维首先付诸于收复香港之实践。在与英方交涉的过程中,邓小平、中国政府表现出强烈的对于香港的主权意识,终于促成了香港回归的起步。