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排序方式: 共有287条查询结果,搜索用时 17 毫秒
61.
French Fiction:     
The cataloging of music sound recordings is both challenging and interesting. As the technologies used to produce sound recordings change, these changes must be reflected in both cataloging theory and practice. Three formats: analog disc, cassette tape, and compact disk, all of which are readily available on the market, present special challenges to catalogers who must consider what might be the most effective way of handling these materials following the AACR2 cataloging rules and interpretations from Library of Congress. This paper examines the actual cataloging of those formats as done by several institutions and raises questions such as how to handle these materials in ways which will eliminate redundancy and increase efficiency in the practice of cataloging. Finally, an alternative approach, drawing on AACR2 practice in other areas, is suggested.  相似文献   
62.
On May 18, 2009, British computer scientist Stephen Wolfram officially launched a new search product called Wolfram|Alpha (WA). This launch was preceded by months of speculation and hype online about exactly what WA would be and how it would compare to Google and other search engines. This article will explore the basic features of WA, show some example queries and results, and discuss the usefulness and limitations of this new tool.  相似文献   
63.
ABSTRACT

Libraries are quite practiced at outreach activities in the physical world, but now, just as our services and resources have moved online, so must our outreach efforts. This article provides a list of twenty practical things libraries can do to begin to delve into the world of online outreach. Topics covered include listing your library in Wikipedia, listing library events in local community calendars, listing librarians in expert-finding directories, pushing newsletters out via RSS, being present in online game and other environments, and much more. The requirements for online outreach at libraries will always be evolving, but this starter list will provide a place for all libraries to begin their foray into online outreach and marketing.  相似文献   
64.
The College of St. Benedict and St. John's University Library have used WorldCat Local as a discovery tool since 2008. After four years of use and numerous anecdotes about the difficulties encountered with this product, a committee was formed to test the tool's usability and effectiveness. Seven female and six male students were asked to find appropriate materials within WorldCat Local for a mock research assignment. The students’ research and thought processes were recorded and studied. The recordings were analyzed by the committee, and the search strategies as well as the materials selected by the students were evaluated and scored. Although the sample size limits generalizability, the videos provided an in-depth look into the students’ research processes and their evaluation of what they found. Students generally fared well when asked to identify suitable books for their research topic, but they encountered many difficulties interpreting article records and identifying appropriate articles. Some WorldCat Local interface features appeared to be either the source of student problems or were not used effectively. Anyone wanting to replicate this study in his or her own evaluation of a discovery tool will want to be aware of the issues encountered in this evaluation of WorldCat Local.  相似文献   
65.
大型空冷汽轮机末级叶片设计技术条件讨论   总被引:1,自引:0,他引:1  
本文在总结国内外制造商有关空冷末级叶片设计方面的技术特性,及相应技术规范基础上,提出了空冷末级叶片设计的技术条件,实现既统一技术术语和基本准则,又放宽具体结构和保留独自风格的空冷末级叶片设计方法。为制订供国内汽轮机制造行业和发电行业在空冷末级叶片的设计制造及运行方面共同参照执行的一个国家标准提供技术支持。  相似文献   
66.
基于索科洛夫喷射器设计理论,结合IF97水和水蒸气性质通用计算模型,建立了一种通用的工质性质采用真实气体性质进行计算的喷射器设计计算方法;对一给定工作蒸汽热力参数、引射蒸汽热力参数以及出口压力对应最大喷射系数的喷射器进行了设计,结果表明:采用不同的物性计算模型对设计结果有很大的影响。  相似文献   
67.
利用AltaVista、Fast、Google 3种搜索引擎在不同时间对中国大陆10所大学的总网络影响因子进行对比分析,其结果表明:网络影响因子的有效性和可靠性除受其本身定义的局限外,还受到搜索引擎性能的影响;目前根据网络影响因子来分析各大学网站的影响力,并以此来对各大学的综合实力进行排名的做法尚缺乏足够的科学依据。  相似文献   
68.
我国互联网信息挖掘研究现状   总被引:11,自引:0,他引:11  
在对信息挖掘与数据挖掘、信息挖掘与搜索引擎、信息挖掘技术总结的基础上, 对作者群和近几年发表论文的质量进行分析。  相似文献   
69.
利用搜索引擎进行高质量情报检索   总被引:16,自引:0,他引:16  
简述了Internet 上与情报源质量相关的问题, 分析了Internet 主要检索工具——搜索引擎的分类特点、工作原理及优缺点, 阐述了利用搜索引擎等工具进行高质量情报检索的步骤。  相似文献   
70.
阐述搜索引擎的工作原理及其服务类型,并对因特网上一些著名搜索引擎的特性进行简要评析,指出现有搜索引擎存在的问题和未来的发展趋势。  相似文献   
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