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21.
国外网络分类法的发展及对我国网络分类法理论与实践的启示 总被引:5,自引:0,他引:5
论文在分析网络分类法与传统文献分类法差异的基础上,阐述了国外网络分类法的特点、问题、发展趋势以及对我国网络分类法理论与实践的几点启示。 相似文献
22.
Question classification systems play an important role in question answering systems and can be used in a wide range of other domains. The goal of question classification is to accurately assign labels to questions based on expected answer type. Most approaches in the past have relied on matching questions against hand-crafted rules. However, rules require laborious effort to create and often suffer from being too specific. Statistical question classification methods overcome these issues by employing machine learning techniques. We empirically show that a statistical approach is robust and achieves good performance on three diverse data sets with little or no hand tuning. Furthermore, we examine the role different syntactic and semantic features have on performance. We find that semantic features tend to increase performance more than purely syntactic features. Finally, we analyze common causes of misclassification error and provide insight into ways they may be overcome. 相似文献
23.
The purpose of this study is to find a theoretically grounded, practically applicable and useful granularity level of an algorithmically constructed publication-level classification of research publications (ACPLC). The level addressed is the level of research topics. The methodology we propose uses synthesis papers and their reference articles to construct a baseline classification. A dataset of about 31 million publications, and their mutual citations relations, is used to obtain several ACPLCs of different granularity. Each ACPLC is compared to the baseline classification and the best performing ACPLC is identified. The results of two case studies show that the topics of the cases are closely associated with different classes of the identified ACPLC, and that these classes tend to treat only one topic. Further, the class size variation is moderate, and only a small proportion of the publications belong to very small classes. For these reasons, we conclude that the proposed methodology is suitable to determine the topic granularity level of an ACPLC and that the ACPLC identified by this methodology is useful for bibliometric analyses. 相似文献
24.
Zhigang Hu Wencan Tian Shenmeng Xu Chunbo Zhang Xianwen Wang 《Journal of Informetrics》2018,12(4):1133-1145
InCites Essential Science Indicators is becoming increasingly used to identify top-performing research and evaluate the impact of institutes. Unfortunately, our study shows that ESI indicators, as well as other normalized citation indicators, have the following flaws. First, the publication month and the online-to-print delay affect a paper’s probability of becoming a Highly Cited Paper (HCP). Papers published in the earlier months of the year are more likely to accumulate enough citation counts to rank at the top 1% compared with those published in later months of the year. Papers with longer online-to-print delays have an apparent advantage for being selected as HCPs. Research field normalizations lead to the third pitfall. Different research fields have different citation thresholds for HCPs, making research field classification important for a journal. In addition, the uniform thresholds for both articles and reviews in ESI affect the reliability of HCP selection because, on average, reviews tend to have higher citation rates than articles. ESI’s selection of HCPs provides an intuitive feel for the problems of normalized citation impact indicators, such as those provided in InCites and SciVal. 相似文献
25.
[目的/意义]学术竞争力被普遍认为是衡量学科可持续发展的关键要素;通过图书情报学(简称"图情")高被引论文的内容结构特征阐释图情学术竞争力不足的影响因素并揭示其成因。[方法/过程]融合社会分层理论、市场效率理论和资源基础理论提出学术竞争力模型,构建"体裁-学术规范-社会效应"内容分析框架,利用中国知网全文数据库图情重点期刊2009-2013年80篇高被引论文、6552条引文开展内容分析。[结果/结论]高被引论文之报导型、基础型、应用型和综述型的体裁分布依次为78.8%、3.75%、10%和7.5%,且报导型以图书馆职业研究为主;高被引论文职业实践效应明显,基础社会效应相对不足。上述发现表明,图情学科学术竞争力不足跟论文的体裁结构和社会效应水平紧密相关,职业化是导致学术竞争力不足的根源。因此,就教育层面而言,推进学科转型是一条必由之路。 相似文献
26.
This paper describes features and methods for document image comparison and classification at the spatial layout level. The methods are useful for visual similarity based document retrieval as well as fast algorithms for initial document type classification without OCR. A novel feature set called interval encoding is introduced to capture elements of spatial layout. This feature set encodes region layout information in fixed-length vectors by capturing structural characteristics of the image. These fixed-length vectors are then compared to each other through a Manhattan distance computation for fast page layout comparison. The paper describes experiments and results to rank-order a set of document pages in terms of their layout similarity to a test document. We also demonstrate the usefulness of the features derived from interval coding in a hidden Markov model based page layout classification system that is trainable and extendible. The methods described in the paper can be used in various document retrieval tasks including visual similarity based retrieval, categorization and information extraction. 相似文献
27.
国际科学学主题共词网络的可视化研究 总被引:23,自引:1,他引:22
采用可视化手段对国际科学学与科学计量学领域中六种核心期刊的高频关键词的共词网络进行了分析,利用社会网络分析的方法对共词网络进行聚类。研究表明,科学、技术和创新活动的研究是科学学与科学计量学的主题。并在此基础上对科学学研究的若干热点、未来的研究方向进行了预测。 相似文献
28.
徽州文书分类整理要点和疑难解析 总被引:1,自引:0,他引:1
徽州文书分类整理是一项学术性很强的科研工作,需要一整套科学规范的分类著录体系和正确合理的工作方法,要求整理人员掌握丰富的历史知识和多种专门业务知识。在分类整理中最常遇见的疑难问题是土地文书中名实不符、内容不清、地点不明和复合契四种,必须准确地解析文书所涉及的各种关系,根据文书真实内容确定类目。 相似文献
29.
信息素质教育和专业素质教育有着极为密切的关系。文章提出开展专业信息素质教育的构想,即将信息素质教育融入院系专业教学工作中,数字化信息资源与教材配套使用,在专业课教学过程中渗透对数字化信息资源的学与用,藉此实现专业素质教育和信息素质教育的兼顾和双赢,解决长期困扰高校信息素质教育被动无力难题,并对其可行性和实施步骤进行初步的探讨。 相似文献
30.
开创情报学的未来——争论的焦点问题研究 总被引:10,自引:0,他引:10
本文概括了当前中国情报界争论的10类观点,体现在2个层面上和集中在1个焦点上。通过对焦点问题的解读,试图破解争论,统一认知,共同推进情报学的学科发展。 相似文献