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1.
Philip E. Schreur 《Cataloging & classification quarterly》2020,58(3-4):397-402
AbstractThe transformation of library metadata encoded in MARC to linked data will enable libraries to participate in the Semantic Web. This transformation, however, will be an iterative development dependent upon community-based decisions. The PCC, as a community-based organization, is ideally positioned to lead this transformation. As PCC guides this transition, three broad areas must be resolved: the conversion of legacy data to linked data, the use of identifiers to support controlled headings, and the transformation of current workflows to linked-data counterparts. By embracing the Web as a community, PCC can confirm its relevance in a complex web of global data. 相似文献
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Minh-Tien Nguyen Viet Cuong Tran Xuan Hoai Nguyen Le-Minh Nguyen 《Information processing & management》2019,56(3):495-515
In the context of social media, users usually post relevant information corresponding to the contents of events mentioned in a Web document. This information posses two important values in that (i) it reflects the content of an event and (ii) it shares hidden topics with sentences in the main document. In this paper, we present a novel model to capture the nature of relationships between document sentences and post information (comments or tweets) in sharing hidden topics for summarization of Web documents by utilizing relevant post information. Unlike previous methods which are usually based on hand-crafted features, our approach ranks document sentences and user posts based on their importance to the topics. The sentence-user-post relation is formulated in a share topic matrix, which presents their mutual reinforcement support. Our proposed matrix co-factorization algorithm computes the score of each document sentence and user post and extracts the top ranked document sentences and comments (or tweets) as a summary. We apply the model to the task of summarization on three datasets in two languages, English and Vietnamese, of social context summarization and also on DUC 2004 (a standard corpus of the traditional summarization task). According to the experimental results, our model significantly outperforms the basic matrix factorization and achieves competitive ROUGE-scores with state-of-the-art methods. 相似文献
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Fatemeh Lashkari Ebrahim Bagheri Ali A. Ghorbani 《Information processing & management》2019,56(3):733-755
Traditional information retrieval techniques that primarily rely on keyword-based linking of the query and document spaces face challenges such as the vocabulary mismatch problem where relevant documents to a given query might not be retrieved simply due to the use of different terminology for describing the same concepts. As such, semantic search techniques aim to address such limitations of keyword-based retrieval models by incorporating semantic information from standard knowledge bases such as Freebase and DBpedia. The literature has already shown that while the sole consideration of semantic information might not lead to improved retrieval performance over keyword-based search, their consideration enables the retrieval of a set of relevant documents that cannot be retrieved by keyword-based methods. As such, building indices that store and provide access to semantic information during the retrieval process is important. While the process for building and querying keyword-based indices is quite well understood, the incorporation of semantic information within search indices is still an open challenge. Existing work have proposed to build one unified index encompassing both textual and semantic information or to build separate yet integrated indices for each information type but they face limitations such as increased query process time. In this paper, we propose to use neural embeddings-based representations of term, semantic entity, semantic type and documents within the same embedding space to facilitate the development of a unified search index that would consist of these four information types. We perform experiments on standard and widely used document collections including Clueweb09-B and Robust04 to evaluate our proposed indexing strategy from both effectiveness and efficiency perspectives. Based on our experiments, we find that when neural embeddings are used to build inverted indices; hence relaxing the requirement to explicitly observe the posting list key in the indexed document: (a) retrieval efficiency will increase compared to a standard inverted index, hence reduces the index size and query processing time, and (b) while retrieval efficiency, which is the main objective of an efficient indexing mechanism improves using our proposed method, retrieval effectiveness also retains competitive performance compared to the baseline in terms of retrieving a reasonable number of relevant documents from the indexed corpus. 相似文献
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This study set out to investigate the effects of positive affectivity (PA) on expatriate creativity and perceived performance in the host country workplace. Most importantly, the study examined the moderating role of perceived cultural novelty in the relationship between PA and creativity and its consequences for the indirect association between PA and perceived performance as mediated via creativity. Data from 297 expatriates in Denmark were collected and hypotheses were tested using regression-based analyses. Consistent with predictions, findings showed a positive relationship between PA and creativity. In addition, PA was positively associated with perceived performance. Results of mediation analysis indicated that creativity mediated the effects of PA on perceived performance. While a moderating effect of perceived cultural novelty in the relation between PA and creativity was found, this moderation was in the opposite direction of the postulated hypothesis, i.e. the positive association between PA and creativity was strongly attenuated at high levels of perceived cultural novelty. Subsequent moderated mediation analysis showed that the identified mediation ceased to exist at high levels of perceived cultural novelty. 相似文献
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依据科学和艺术内在本质的关联,以及科学的艺术诉求与呈现;从科技期刊编辑的主体和客体出发,阐述了科技期刊编辑出版艺术性的内涵以及在相关环节的具体表现,即科技期刊编辑出版的艺术性既指编辑产物——客体(期刊内外形式)细节、局部和整体的艺术呈现与美学蕴涵,也指编辑主体为实现这种美的个性化创造而展开的具有独创性的思维运作过程。科技期刊编辑的艺术性,成就了寓含品牌特征的个性化期刊。 相似文献
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The Inductive Query By Example (IQBE) paradigm allows a system to automatically derive queries for a specific Information Retrieval System (IRS). Classic IRSs based on this paradigm [Smith, M., & Smith, M. (1997). The use of genetic programming to build Boolean queries for text retrieval through relevance feedback. Journal of Information Science, 23(6), 423–431] generate a single solution (Boolean query) in each run, that with the best fitness value, which is usually based on a weighted combination of the basic performance criteria, precision and recall. 相似文献
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基于WEB的信息检索多媒体CAI课件的优化设计 总被引:6,自引:0,他引:6
本文介绍了基于Web的信息检索多媒体CAI课件的实质,在分析信息检索多媒体CAI课件利弊的基础上,探讨了基于Web的信息检索多媒体CAI课件优化设计应遵循的原则及开发的一般策略。 相似文献
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评介了60年代以来比较著名的几种引文标引理论,并在此基础上提出了“无标引的引文检索”方法。作者利用该方法的基本原理进行了局部试验,结果显示良好。认为如果将引文标引检索与主题标引检索结合起来,可更好地提高情报检索效率。 相似文献