共查询到20条相似文献，搜索用时 468 毫秒
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通过对检索系统所提供的主题词、关键词、作者提供的关键词这三种用户常用的检索方式进行选词测试,比较它们的检索效率,从而了解这三种检索方法的特点,并以此为用户提供检索建议. 相似文献
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新版PubMed引文检索功能及全文获取 总被引：1，自引：0，他引：1
本文介绍因特网上免费生物医学检索系统PubMed新版提供的引文查询功能.告知广大信息用户,可以利用这一检索途径检索部分被PubMed收录的著者或论文被引用情况,扩大引文查询的检索范围.此外,还介绍了如何快速检索和获取PubMed收录的期刊全文. 相似文献
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通过对Ei和INSPEC两种光盘数据库在Windows界面的检索软件、检索模式、检索方法以及输出功能进行详细的比较研究，分析评价了两种检索系统的异同和各自的优越性，帮助用户有效地使用这两种光盘数据库。 相似文献
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医学文献检索中检索词的选择 总被引：3，自引：0，他引：3
目的：探讨医学文献检索中如何对检索词（主题词和自由词等）进行适当的选择。方法：从检索概念入手，比较主题词和自由词检索的异同，并通过典型实例对两种方法在不同数据库（Medline，CBM）的检索结果进行分析。结果：Medline数据库使用主题词法检索效果优于自由词法；CBM数据库用主题词法检索查全率和查准率较高，但检索最新主题文献时，自由词法检索的效果更佳。结论：因为检索系统固有的局限性、文献标引等原因．主题词和自由词检索各有优缺点。适用范围不同，要使查全率和查准率达到理想的平衡点．两者联合使用效果最佳。 相似文献
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《中刊库》的网络检索与光盘检索的比较研究 总被引：2，自引：1，他引：1
针对《中刊库》的两种检索系统——网络检索与光盘检索,对它们的检索特点及应用方法进行介绍,并就最常用的检索方法举若干检索实例进行比较研究,并提出实际可行的建议. 相似文献
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试论提高分类检索在机检中的效率 总被引：2，自引：0，他引：2
本文认为在数据库检索系统中,分类检索应改变传统观念,从用户检索需求出发,以新的思维方式来设计用户分类检索方法,从而提高分类检索的效率。 相似文献
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对中外三大学位论文全文数据库的比较研究 总被引：3，自引：0，他引：3
以中外三大学位论文全文数据库为研究对象，对三大数据库的数据来源、检索方法、检索功能、检索效率进行比较研究与探讨，并提出改进检索系统的几点建议，其目的是为今后数据库的进一步完善和改进提供参考，为广大的用户获取学位资源提供帮助。 相似文献
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简要介绍了同族专利的作用及同族专利的检索,重点对欧洲专利局专利检索系统和德温特数据库两大检索系统处理同族专利的方法,以及利用同族专利信息向公众提供服务的角度与思路进行了比较研究. 相似文献
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以4种综合类科技核心期刊2007-2009年的载文为样本,对其网络引文量的变化趋势、网络引文顶级域名的分布情况以及网络引文著录规范化等方面进行计量分析,力图揭示我国科技领域研究人员对网络信息资源的利用状况,以期促进网络文献管理的规范化和科学化。 相似文献
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This study investigates how business research scholars’ internationalization strategies influence their research performance and how this relationship is moderated by the availability of different knowledge-based resources. The authors analyze citations to journal articles authored by business research scholars with German affiliations and examine how the number of citations is determined by international collaborations and a researcher's knowledge resources in terms of language skills, research experience, and foreign market knowledge. The results demonstrate that the augmentation of complementary knowledge resources (i.e., when researchers lack language skills and foreign market knowledge) positively influences the performance of a collaboration-based internationalization strategy (i.e., collaborations with international researchers). The collaboration-based strategy also improves performance for less experienced researchers, but this advantage diminishes with increasing research experience. The findings provide further insights into drivers of scholars’ research performance and have practical implications for science policy. 相似文献
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The concept of an “information space” provides a powerful metaphor for guiding the design of interactive retrieval systems. We present a case study of related article search, a browsing tool designed to help users navigate the information space defined by results of the PubMed® search engine. This feature leverages content-similarity links that tie MEDLINE® citations together in a vast document network. We examine the effectiveness of related article search from two perspectives: a topological analysis of networks generated from information needs represented in the TREC 2005 genomics track and a query log analysis of real PubMed users. Together, data suggest that related article search is a useful feature and that browsing related articles has become an integral part of how users interact with PubMed. 相似文献
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《中国地理科学》（英文版）是我国创办最早的综合性英文地理期刊,分析其发文被引用情况可以了解该刊十几年来变化情况,又可以为刊物今后的发展方向提供依据。本文利用Web of Science的引文检索功能,统计了该刊2002-2012年的被引用情况,从载文量、篇均被引频次、单篇被引频次、被引频次年代分布、被引论文专业分布和引文类型分布等几个方面,基于地理学学科特点和文献计量学方法进行综合分析,总结该刊目前发展存在的问题及改进措施,以期为刊物发展提供参考,更好地促进地理学科的发展。 相似文献
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《Information processing & management》2020,57(5):102267
Merging the citation counts of arXiv-deposited e-prints (arXiv version) with those of their corresponding published journal articles (publisher version) is an important issue in citation analysis. Using examples of arXiv-deposited e-prints, this article adopts a manual approach to investigate the processing methods used by bibliographic repositories such as Google Scholar, Web of Science, Scopus, Astrophysics Data System (ADS), and INSPIRE for the citation merging. Both Google Scholar and ADS consolidate all citations from the two versions into the publisher one, whereas the consolidated citations are accumulated into the arXiv version in the INSPIRE repository. All these methods ignore the categories of the arXiv-deposited versions and the corresponding availability dates. As for Web of Science and Scopus, they count the citations of the two versions separately, which is likely regarding them as two independent articles. Focusing on journal articles that also appeared as arXiv e-prints, we classify them into two categories and identify two public availability dates of articles as the starting point of citation statistics. We present four feasible schemes to consolidate citation counts for the articles with both versions and also propose a universal scheme based on the research output. Furthermore, we investigated 2,662 e-prints in the “Computer Science - Digital Libraries” subject (cs.DL) from 1998 to 2018 in arXiv.org and manually calculated the consolidated citation counts of arXiv-deposited articles with the corresponding citation merging schemes. Furthermore, these citation consolidation methods are applied to the evaluation of articles, authors, and journals. Such empirical testing proves the feasibility of the schemes proposed in this article. 相似文献
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【目的】采用H指数和二八法则基于文献的被引频次来划分出期刊文献的核心区,为科研工作者提供一种把握研究热点的新方法。【方法】 以WoS中收录的84种的图书情报学期刊15592篇文献为研究样本,并采用H指数和二八法则基于文献的被引频次来划分出期刊文献的核心区。【结果】采用二八法则划分文献核心区,其核心区文献量占总文献量为6.12%~48.61%,均值为33.81%;而采用H指数划分文献核心区,其核心区文献量占总文献量为0.56%~26.09%,均值为7.80%。对学科采用二八法则划分文献核心区,其核心区文献量占总文献量80%的文献量为38.05%;采用H指数划分文献核心区,其核心区文献占总文献量为0.67%。核心区文献篇均被引频次为H指数划分大于二八法则划分。【结论】采用H指数划分期刊文献核心区比二八法则更具集中趋势,故而H指数能更好地划分出期刊文献核心区。 相似文献
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Edgardo Ferretti Leticia Cagnina Viviana Paiz Sebastián Delle Donne Rodrigo Zacagnini Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published. 相似文献