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排序方式: 共有9416条查询结果,搜索用时 15 毫秒
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prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove).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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Hana Tur‐Kaspa 《Learning disabilities research & practice》2004,19(1):3-11
The study examined the social‐information‐processing skills of kindergarten children with developmental learning disabilities (LD) utilizing Crick and Dodge's (1994) model of children's social adjustment as a theoretical framework. Participants consisted of 20 kindergarten children with developmental LD who attended three integrated kindergartens and 20 children without developmental LD from the same kindergartens. Participants were assessed on social‐information‐processing skills, feelings of loneliness, sense of coherence, and teachers' ratings of behavioral problems and positive resources. The results indicated that girls with developmental LD performed significantly lower on two information‐processing steps—the response decision and the enactment steps—than did girls without LD. Such differences were not found for boys. The results also showed that the social‐information‐processing skills of children with developmental LD were correlated with teachers' ratings. 相似文献
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运用类比推理的方法,将经过三角形重心的直线的性质推广到三维空间,导出经过三角形重心的平面的若干性质. 相似文献
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运动员心脏功能典型指标的选择与评价 总被引:1,自引:0,他引:1
任建生 《武汉体育学院学报》1996,(1)
本研究运用相关检验和聚类分析法等对三十多个心脏形态、功能指标进行了筛选分析,选择出适合评定运动员心脏功能的典型指标,并对所选指标的应用进行了评价。 相似文献
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在同一律教学中 ,要注意讲清什么是“同一思维过程”、什么是“A是A”以及“合理违反同一律”的特殊情况。在不矛盾律教学中 ,要注意讲清“看似矛盾 ,实质上并不矛盾”的概念或判断 ,注意分析具有隐蔽性的逻辑矛盾。在排中律教学中 ,对人们的某些思维或表述 ,要结合语言环境加以分析 ,不能生搬硬套 相似文献