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科技政策研究代表人物与核心文献可视化网络 总被引：2，自引：0，他引：2
引文计量方法常被用来确定某一研究领域的代表人物与核心文献。以国际科学技术政策研究权威期刊《科研政策》（Research Policy）的全部引文数据作为样本,通过作者共被引分析与文献共被引分析,确定了国际科技政策研究领域的代表人物与核心文献;并在此基础上,利用信息可视化技术,绘制出科技政策研究领域代表人物与核心文献的可视化网络,为科技政策研究者提供重要参考。 相似文献
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Frizo Janssens Lin Zhang Bart De Moor Wolfgang Glnzel 《Information processing & management》2009,45(6):683-702
A hybrid text/citation-based method is used to cluster journals covered by the Web of Science database in the period 2002–2006. The objective is to use this clustering to validate and, if possible, to improve existing journal-based subject-classification schemes. Cross-citation links are determined on an item-by-paper procedure for individual papers assigned to the corresponding journal. Text mining for the textual component is based on the same principle; textual characteristics of individual papers are attributed to the journals in which they have been published. In a first step, the 22-field subject-classification scheme of the Essential Science Indicators (ESI) is evaluated and visualised. In a second step, the hybrid clustering method is applied to classify the about 8300 journals meeting the selection criteria concerning continuity, size and impact. The hybrid method proves superior to its two components when applied separately. The choice of 22 clusters also allows a direct field-to-cluster comparison, and we substantiate that the science areas resulting from cluster analysis form a more coherent structure than the “intellectual” reference scheme, the ESI subject scheme. Moreover, the textual component of the hybrid method allows labelling the clusters using cognitive characteristics, while the citation component allows visualising the cross-citation graph and determining representative journals suggested by the PageRank algorithm. Finally, the analysis of journal ‘migration’ allows the improvement of existing classification schemes on the basis of the concordance between fields and clusters. 相似文献
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Bibliometric cartography of information retrieval research by using co-word analysis 总被引：6，自引：0，他引：6
The aim of this study is to map the intellectual structure of the field of Information Retrieval (IR) during the period of 1987–1997. Co-word analysis was employed to reveal patterns and trends in the IR field by measuring the association strengths of terms representative of relevant publications or other texts produced in IR field. Data were collected from Science Citation Index (SCI) and Social Science Citation Index (SSCI) for the period of 1987–1997. In addition to the keywords added by the SCI and SSCI databases, other important keywords were extracted from titles and abstracts manually. These keywords were further standardized using vocabulary control tools. In order to trace the dynamic changes of the IR field, the whole 11-year period was further separated into two consecutive periods: 1987–1991 and 1992–1997. The results show that the IR field has some established research themes and it also changes rapidly to embrace new themes. 相似文献
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[目的/意义]随着科学技术的高速发展、知识交叉越来越多、科学与社会的关系越来越复杂,如何利用计量学的原理、方法与工具处理这些错综复杂的关系显得尤为重要,可见进一步厘清我国计量学发展轨迹具有重要意义。[方法/过程]本文基于CNKI、CSSCI数据库,利用可视化软件,对国内已有的文献进行分析,探析国内计量学发展的研究演进过程,通过文献的梳理分析,使用文献的共引分析、共词分析方法对我国计量学发展轨迹及研究趋势进行可视化分析。[结果/结论]本文通过文献共被引分析,发现我国计量学研究的两个核心领域;通过作者共被引分析,发现研究主题演进过程中代表人物及其更替;通过关键词共现分析,掌握目前国内"五计学"研究热点的演进。 相似文献
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Peretz Shoval 《Information processing & management》1985,21(6):475-487
An expert system was developed in the area of information retrieval, with the objective of performing the job of an information specialist, who assists users in selecting the right vocabulary terms for a database search.The system is composed of two components: One is the knowledge base, represented as a semantic network, in which the nodes are words, concepts, phrases, comprising a vocabulary of the application area and the links express semantic relationships between those nodes. The second component is the rules, or procedures, which operate upon the knowledge-base, analogous to the decision rules or work patterns of the information specialist.Two major stages comprise the consulting process of the system: During the “search” stage relevant knowledge in the semantic network is activated, and search and evaluation rules are applied in order to find appropriate vocabulary terms to represent the user's problem. During the “suggest” stage those terms are further evaluated, dynamically rank-ordered according to relevancy, and suggested to the user. Explanations to the findings can be provided by the system and backtracking is possible in order to find alternatives in case some suggested term is rejected by the user.This article presents the principle, procedures and rules which are utilized in the expert system. 相似文献
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[研究目的]寻找国内情报学领域期刊论文研究热点的分布特性,探讨我国情报学领域学术研究热点的基本演变轨迹。[研究方法]选择国内情报学领域21种期刊论文的关键词进行统计分析,统计时间从2000年至2020年,统计数据在万方数据库中进行。首先选择年度排序在前30次以上的关键词作为热点研究的统计对象,由此从中选出60个关键词作为情报期刊的基本热点关键词。其次用选出的60个关键词在万方数据库的全学科(注:这里的全学科指在万方数据库收录的所有学科)关键词中进行检索,检索时间为2000年至2020年,最后对比分析情报期刊的热点关键词在全学科中的个性化特征和全局性分布特征。[研究结论]实验结果表明,该统计分析揭示了我国情报期刊论文近20年来三个阶段的热点关键词演变轨迹。情报学热点关键词与全学科关键词存在超前和滞后现象,反映了情报学科与全学科具有相互学习和相互推进的发展规律,借此规律对我国未来情报学热点进行预测,预测出我国情报期刊论文未来延续出现和可能出现的72个热点关键词。 相似文献
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Henry Small 《Information processing & management》1981,17(1):39-50
A co-citation cluster analysis of a three year (1975–1977) cumulation of the Social Sciences Citation Index is described, and clusters of information science documents contained in this data-base are identified using a journal subset concentration measure. The internal structure of the information science clusters is analyzed in terms of co-citations among clusters, and external linkages to fields outside information science are explored. It is shown that clusters identified by the journal concentration method also cohere in a natural way through cluster co-citation. Conclusions are drawn regarding the relationship of information science to the social sciences, and suggestions are made on how these data might be used in planning an agenda for research in the field. 相似文献
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共引分析：研究学科及其文献结构和特点的一种有效方法 总被引：12，自引：2，他引：12
利用聚类分析和多维标度技术对1987年农业科学文献进行了文章共引分析,即按被引次数及共引情况选出28篇文章作为分析对象,用多维标度技术把高维引文空间中的28个文献点以二维散点图的形式表示出来,并把这些点通过聚类分析圈成点群,根据这样的圈所提供的信息,分析讨论了农业科学及其文献的结构和特点。 相似文献
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[目的/意义]已有研究对文献耦合关系和同被引关系比较的研究较少，本文比较两种关系在文献间建立联系的差异，并且比较耦合/同被引强度与文献相似度的相关性，分析耦合分析和同被引分析各自更适合哪些方面的应用。[方法/过程]根据复杂网络理论，构建文献耦合网络和同被引网络，实证比较文献耦合网络和同被引网络的拓扑性质。利用QAP关联分析，研究耦合关系、同被引关系与文献内容相似度的关系。[结果/结论]网络拓扑结构分析表明，耦合关系在文献之间建立的联系更普遍而且更稳定，更利于检索被引用次数较少的大多数文献；同被引关系在高被引文献之间建立的联系更紧密，利于检索和确定领域内的核心文献。QAP关联分析表明耦合强度和文献相似度的相关性更强，在文献聚类分析研究主题时，耦合强度更可靠。 相似文献
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鉴于传统方法对科研成果关键词研究存在较强主观影响和较少考虑时间因素等问题,提出基于时间序列聚类的科研成果关键词分析方法。该方法通过统计分析方法验证关键词出现顺序在一定程度上反映了关键词反映主题思想的重要性,将关键词的重要度转化为时间序列数据,分别从重要度的数值和趋势两个角度出发,使用动态时间弯曲方法度量关键词重要度时间序列数据之间的相似性,结合近邻传播方法对关键词时间序列数据之间的相似性矩阵进行聚类分析,实现科研成果的关键词分析研究。通过对某科研管理类重要期刊2008—2017年期间刊发的科研成果论文关键词研究发现：新方法不仅可以对科研成果中关键词的关注热度和趋势进行聚类划分,自适应地找到中心关键词作为相应类别的特征代表对象,还能为科研成果关键词的主题分析提供理论方法和决策支持。 相似文献
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Researchers in indexing and retrieval systems have been advocating the inclusion of more contextual information to improve results. The proliferation of full-text databases and advances in computer storage capacity have made it possible to carry out text analysis by means of linguistic and extra-linguistic knowledge. Since the mid 80s, research has tended to pay more attention to context, giving discourse analysis a more central role. The research presented in this paper aims to check whether discourse variables have an impact on modern information retrieval and classification algorithms. In order to evaluate this hypothesis, a functional framework for information analysis in an automated environment has been proposed, where the n-grams (filtering) and the k-means and Chen’s classification algorithms have been tested against sub-collections of documents based on the following discourse variables: “Genre”, “Register”, “Domain terminology”, and “Document structure”. The results obtained with the algorithms for the different sub-collections were compared to the MeSH information structure. These demonstrate that n-grams does not appear to have a clear dependence on discourse variables, though the k-means classification algorithm does, but only on domain terminology and document structure, and finally Chen’s algorithm has a clear dependence on all of the discourse variables. This information could be used to design better classification algorithms, where discourse variables should be taken into account. Other minor conclusions drawn from these results are also presented. 相似文献
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基于知识图谱的我国期刊评价研究评述 总被引：2，自引：0，他引：2
利用新的文献可视化手段,对1998-2009年主题为期刊评价的CSSCI来源文献分析,分别绘制了作者、关键词、作者共被引、期刊共被引、文献共被引知识图谱。解读和评述了期刊评价领域的特点。h指数、CSSCI、web即年下载率等是热点话题;知识源主要集中在图书馆情报与文献学、新闻与传播学两类学科期刊;核心期刊、人文社会科学期刊、h指数等评价指标研究是期刊评价研究的三个主要知识领域。 相似文献
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Citing statements can be used to aid retrieval, to increase the efficiency of citation indexes and for the study of information flow and use. These uses are only feasible on a large scale if computers can identify citing statements within the texts of documents with reasonable accuracy.Computer recognition of multi-sentence citing statements is not easy. Procedures developed for chemistry papers in an earlier experiment were tested on biomedical papers (dealing with various aspects of cancer) and were almost as successful. Specifically, (1) 78% of the words in computer-recognized citing statements were correctly attributable to the corresponding cited papers; and (2) the computer procedures missed 4% of the words in the actual citing statements. When the procedures were modified on the basis of those results and tested on a new sample of cancer papers the results were comparable: 72 and 3% respectively.In an earlier experiment in use of full-text searching to retrieve answer-passages from cancer papers, recall in the “test phase” averaged about 70% and the false retrieval rate was thirteen falsely retrieved sentences per answer-paper retrieved. Unretrieved answer-papers in that experiment's “development phase”, and citing statements referring to them, were studied to develop computer procedures for using citing statements to increase recall. The procedures developed only produced slight recall increases for development phase answer-papers, and similarly for the test phase papers on which they were then tested. Specifically, the test phase results were the following: recall was increased from 70 to 74%, and there was no increase in false retrieval. This contrasts with an earlier experiment in which 50% recall of chemistry papers by search of index terms and abstract words was increased to 70% by the addition of words from citing statements. The difference may be because the average number of citing papers per unretrieved cancer paper was only six while that for chemistry papers was thirteen. 相似文献
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[目的/意义]关键词是反映期刊研究主题、研究方法和数据源等信息的重要途径。本文尝试通过论文关键词来研究学术期刊的相似度,为期刊分类等学术研究和实际工作提供参考。[方法/过程]首先,在相关文献梳理的基础上,提出了基于论文关键词的两种期刊相似度计算方法。然后,以《中国图书馆学报》和《情报学报》为实证对象,从CSSCI采集了两种期刊1998-2017年的关键词数据。最后,计算了两种期刊的相似度,并分析了两种期刊论文的共现关键词。[结论]研究发现,两种期刊的相似度有一定波动,但整体上呈现为一个下降趋势。这反映出两种期刊上发表的论文的相似性在不断下降,而差异性在不断增加。 相似文献
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基于同被引分析的我国图书馆学情报学期刊关系与结构研究 总被引：1，自引：0，他引：1
本文在选取我国图书馆学情报学领域24种典型期刊的基础上,利用期刊同被引分析方法对从CNKI中检索出的1999—2009年的期刊同被引数据进行了分析,包括聚类分析、多维尺度分析和因子分析,得出了期刊的关系与结构及其在图书馆学情报学领域中的地位。 相似文献
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图书馆学情报学期刊的同被引研究 总被引：4，自引：0，他引：4
期刊同被引是同被引分析方法的一种,使用该方法可以对图书馆学情报学相关期刊的同被引情况进行研究.本文首先对1996-2006年CNKI中有关图书馆学情报学期刊的同被引数据进行统计,然后运用聚类分析和核心--边缘模型两种方法来处理和分析数据,最后得出相应的结论.通过对分析结果进行解释,试图说明图书馆学情报学期刊之间的关系,并确定该学科的核心期刊. 相似文献
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基于期刊共引分析法的学科关系知识图谱的实证研究 总被引：2，自引：0，他引：2
本文基于期刊共引分析法,利用社会网络分析和Pajek软件,构建中国农史学科与相邻学科关系知识图谱,分析农业史学科与相邻学科的关系。为基于期刊共引分析的学科关系知识图谱的进一步研究提供具体的案例。 相似文献