On the Conditions for the Characteristic Roots of a Matrix in a Sector

Davison and Ramesh expressed equivalently the condition for the characteristic roots of a real matrix to lie within a sector by the condition for a matrixof doubled order to be Hurwitzian (1). A further generalization of their result is given in this note.     

Relations between the shape of a size-frequency distribution and the shape of a rank-frequency distribution

We study the dependence of the shape of the rank-frequency distribution g on the shape of the size-frequency distribution f and vice versa. We show mathematically that g is convexly decreasing if and only if f is monotonically decreasing and that g has an S-shape (i.e., g is first convexly decreasing and then concavely decreasing) if and only if f is first increasing and then decreasing.     

Demystifying the Memories of a Fruitfly

Despite its tiny size, the fruitfly (Drosophila)brain is fairly intricate.Recently a group of neuroscientists from the CAS Institute of Biophysics (IBP) have managed to catch the first glimpse of the circuitry within a fruitfly neural system for visual pattern recognition. The paper entitled "Distinct memory traces for two visual features in the Drosophila brain" by the research group was reported in the February 2 issue of Nature.     

基于有限元的某微型车车架强度分析

基于有限元理论,文章运用HyperWorks和MSC.Patran软件建立了某微型车车架的有限元模型,并通过有限元分析的方法对车架的结构进行仿真分析。对静态弯曲与静态扭转两种典型工况下车架的受力情况进行了计算和应力分析,分析结果表明:该车架受到的最大应力值远小于材料屈服极限,满足设计的要求,为改进结构和轻量化设计提供了重要依据。     

浅论虚拟化及其应用

在介绍虚拟化的概念和起源发展的基础上,阐述了虚拟化的主要应用方向,详细论述了各种虚拟化技术的概念、原理和方法,诸如服务器虚拟化、存储虚拟化和网络虚拟化。     

浅谈高职学生学习素质的培养

所谓学生学习素质,包括学习的主动性和学习能力两个方面,是学生获取知识、提高技能的内在动力表现,也是学生取得良好的学习效果的前提条件。而对于高职学校的学生来说,学习不仅仅是对理论知识的掌握和了解,更重要的是在掌握相对不完善的理论知识的基础上,更多地在实际动手能力上加强训练,形成比较强的实际操作能力和专业技能。     

A study of the information needs of the users of a folk music library and the implications for the design of a digital library system

A qualitative study of user information needs is reported, based on a purposive sample of users and potential users of the Vaughan Williams Memorial Library, a small specialist folk music library in North London. The study set out to establish what the users’ (both existing and potential) information needs are, so that the library’s online service may take them into account with its design. The information needs framework proposed by Nicholas [Nicholas, D. (2000) Assessing information needs: tools, techniques and concepts for the internet age. London: ASLIB] is used as an analytical tool to achieve this end. The demographics of the users were examined in order to establish four user groups: Performer, Academic, Professional and Enthusiast. Important information needs were found to be based on social interaction, and key resources of the library were its staff, the concentration of the collection and the library’s social nature. A collection of broad design requirements are proposed based on the analysis and this study also provides some insights into the issue of musical relevance, which are discussed.     

从一个试验看基金项目同行通讯评审的问题

在基金项目评审中比较普遍采用的方法之一是同行通讯评审,即由同行专家背靠背地对申请项目进行评审.对于同行通讯评审,国内外已研究和运用了多年,其内在优势已为人们普遍承认,即,它可以充分利用科学共同体中的科学家来实现科技资源的合理配置,有助于科学决策的民主化,并杜绝单纯的行政决策.