国外数字资源长期保存政策扫描

本文讨论了数字资源长期保存政策的定义、类型、涉及的问题,分析了国际数字资源长期保存政策的现状,介绍了国外一些典型的数字资源长期保存政策.     

抗战中陈嘉庚的西北之行

在甘肃省档案馆所藏民国档案中,有一纸1940年5月13日甘肃省政府秘书处为欢迎陈嘉庚飞抵兰州事致甘肃省银行的函,内容如下:迳启者:奉司令长官兼主席手谕"华侨慰劳团陈团长嘉庚(同行三人)于明日(十四日)飞兰,所有兰州各机关首领或代表应莅场(飞机场)欢迎"等因;除由本府派员招待并分函外,相应函达,即希查照为荷。     

基于域加权词频法的XML文档级检索实现与评价

利用BM25F模型,通过实验,在INEX 04数据集的基础上,实现了对多个域(元素)词频进行加权的XML文档级检索。XML文档结构的确蕴含了一定的语义信息。利用这些语义信息,可以提高检索性能。表2。图1。参考文献16。     

搜索引擎的技术现状及其发展趋势

介绍了基于文本信息检索的搜索引擎分类和基于内容的多媒体信息检索的搜索引擎技术现状 ,并介绍了每种技术类型的特点。通过分析应用需求、技术发展的现状和遇到的技术问题 ,预测了搜索引擎的发展趋势。     

期刊论文被引用及其Web全文下载的文献计量分析

运用《中国学术期刊综合引证报告》及《中国学术期刊全文数据库Web下载统计报告》的文献计量数据分析了期刊论文网上下载频次的年代分布和被引用频次的年代分布，对比了它们的峰值（百分数）和峰值与统计年的年限差，得到“去年发表的论文被下载多，前年发表的论文被引用多，当年发表的论文下载频次与被引频次的比值高”这一规律性认识。研究了文献的网上下载频次分布和被引用频次的分布，对比了它们的集中系数。鉴于文献网上下载指标的排序与被引用指标的排序并不完全一致，建议将它们都作为独立指标在综合评价中予以适当考虑。     

Back to the Future

The emergence of “fake news” during the Brexit referendum and Trump election campaign sent news organisations scurrying to establish teams of journalists to debunk deliberately misleading stories and verify facts. This paper examines steps to counter false stories and asks whether normative values of objectivity are about to enjoy a comeback. Typical markers of objectivity (freedom from bias, detachment and fact-based reporting) date back to the nineteenth century and, despite being ingrained in the Anglo-American news culture, have always been subject to challenge. Recently, the growth of partisan and populist media has illustrated deep distrust in traditional news outlets and is questioning whether it is time to jettison objectivity. But are we experiencing a backlash? Through interviews with senior UK-based journalists at legacy news organisations and analysis of editorial policy statements prompted by a UK parliamentary inquiry, the paper explores how fake news is rekindling debate about objectivity and its potential to make quality journalism stand out. It argues that legacy news organisations in the United Kingdom have seized the opportunity to highlight the value of normative practices that draw on familiar components of the objectivity paradigm. But few have the financial strength to bolster the rhetoric with additional editorial resources.     

Why Use Multiple Representations in the Mathematics Classroom? Views of English and German Preservice Teachers

Dealing with multiple representations and their connections plays a key role for learners to build up conceptual knowledge in the mathematics classroom. Hence, professional knowledge and views of mathematics teachers regarding the use of multiple representations certainly merit attention. In particular, investigating such views of preservice teachers affords identifying corresponding needs for teacher education. However, specific empirical research is scarce. Taking into account the possible role of culture, this study consequently focuses on views about using multiple representations held by more than 100 English and more than 200 German preservice teachers. The results indicate that there are culture-dependent aspects of preservice teachers’ views, but also that there are common needs for professional development.

     

Teaching the Pursuit of Assumptions

Within the school of thought known as Critical Thinking, identifying or finding missing assumptions is viewed as one of the principal thinking skills. Within the new subject in schools and colleges, usually called Critical Thinking, the skill of finding missing assumptions is similarly prominent, as it is in that subject's public examinations. In this article we examine how school‐ and college‐focused texts explain and teach ‘this very important skill’. The same texts also deal with the nature of assumptions, validity and the role of stated reasons in arguments, and the way these matters are tackled will also be examined in our inquiry. In addition we explore what respected contributors to the critical thinking movement have had to say about some of these issues.