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1.
David Sánchez-Oliva Rebecca M. Leech Alberto Grao-Cruces Irene Esteban-Cornejo Carmen Padilla-Moledo Oscar L. Veiga 《Journal of sports sciences》2020,38(9):1062-1069
ABSTRACTThe aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time. 相似文献
2.
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prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove).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
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Louise L. Stevenson Albert N. Greco Ann Okerson Beth Luey 《Publishing Research Quarterly》1991,7(1):85-91
Association of Research Libraries 相似文献
6.
Renáta Tichá Christine A. Espin Miya Miura Wayman 《Learning disabilities research & practice》2009,24(3):132-142
The validity and reliability of curriculum‐based measures in reading as indicators of performance and progress for secondary‐school students were examined. Thirty‐five grade 8 students completed reading aloud and maze‐selection measures weekly for 10 weeks. Criterion measures were the state standards test in reading and the Woodcock–Johnson III Test of Achievement. Different time frames for each measure were compared. Most alternate‐form reliability coefficients were above .80. Criterion‐related validity coefficients ranged from .77 to .89. No differences related to time were found. Only maze selection reflected significant growth, with an average increase of 1.29 correct choices per week. Maze growth was related to the reading performance level and to change on the Woodcock–Johnson III from pre‐ to posttest. 相似文献
7.
Empirical research provides evidence that electronic communication does not change government agencies into post-bureaucratic organizations. Structuration Theory is used to explore the interaction between e-mail use, communication patterns of civil servants, and two bureaucratic characteristics: formalization and hierarchy. Previous research suggested that the use of e-mail leads to less formalization and less hierarchy, but empirical research in three bureaucratic organizations in the Netherlands leads to different conclusions. First, the use of e-mail leads to informal formalization: the style of communication is more informal but the content focuses less on personal issues and emphasizes efficient recordings of agreements. Second, the use of e-mail leads to hierarchical horizontalization: horizontal contacts take a more central position in bureaucratic organizations but these horizontal contacts are tightly linked to vertical structures. The result of the interaction between e-mail and government bureaucracy is horizontal communication directly linked to vertical structures. Electronic communication turns government agencies into late-bureaucratic organizations. 相似文献
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Among the huge maze of resources available on the Internet, UnCoverWeb stands out as a valuable tool for medical libraries. This up-to-date, free-access, multidisciplinary database of periodical references is searched through an easy-to-learn graphical user interface that is a welcome improvement over the telnet version. This article reviews the basic and advanced search techniques for UnCoverWeb, as well as providing information on the document delivery functions and table of contents alerting service called Reveal. UnCover's currency is evaluated and compared with other current awareness resources. System deficiencies are discussed, with the conclusion that although UnCoverWeb lacks the sophisticated features of many commercial database search services, it is nonetheless a useful addition to the repertoire of information sources available in a library. 相似文献
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Albert Endres 《Informatik - Forschung und Entwicklung》2004,18(2):88-93
Zusammenfassung. Information ist der wichtigste Grundbegriff der Informatik. Ein semantischer Ansatz erklärt Information als Bedeutung einer Nachricht für ihren Empfänger. Als Folge davon hängt der Informationsgehalt einer Datei, einer Datenbank, eines Buches oder eines Filmes von der Interpretation ab, die ein Nutzer vornehmen kann oder gerade vornimmt. Informationsmaße werden sowohl von der Lesbarkeit einer Nachricht als auch von der Qualität des Interpreten bestimmt. Information kann neu entstehen, verloren gehen oder verändert werden.CR Subject Classification:
E.4, H.1 相似文献