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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
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In South Africa the education system for black children is fraught with problems. These problems are the direct result of apartheid and have been compounded by poverty and illiteracy. In this article the problem of poorly qualified or unqualified teachers is discussed especially with regard to the teaching of map skills to children in their fifth school year. The project team needed to develop affordable materials which could be used in large classes by teachers after a very short period of training. Books and other materials which are available commercially were examined, but for various reasons were found to be unsuitable for local conditions. After determining the extent of the problem, the project team followed a grassroots process of developing a flip chart which teachers learnt to use with confidence and which enabled pupils to master the concepts and skills necessary for understanding a map. 相似文献
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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
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Krister Lindén 《Information Retrieval》2006,9(3):295-310
Technical term translations are important for cross-lingual information retrieval. In many languages, new technical terms
have a common origin rendered with different spelling of the underlying sounds, also known as cross-lingual spelling variants
(CLSV).
To find the best CLSV in a text database index, we contribute a formulation of the problem in a probabilistic framework, and
implement this with an instance of the general edit distance using weighted finite-state transducers. Some training data is
required when estimating the costs for the general edit distance. We demonstrate that after some basic training our new multilingual
model is robust and requires little or no adaptation for covering additional languages, as the model takes advantage of language
independent transliteration patterns.
We train the model with medical terms in seven languages and test it with terms from varied domains in six languages. Two
test languages are not in the training data. Against a large text database index, we achieve 64–78 % precision at the point
of 100% recall. This is a relative improvement of 22% on the simple edit distance. 相似文献
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Tatjana Bayerová 《文物保护研究》2018,63(3):171-188
The technical study of wall paintings from the Buddhist temple complex at Nako, Western Himalayas, was one of the basic preconditions required for designing an appropriate conservation strategy. The complex, composed of four temples from the eleventh–twelfth century, offered a unique possibility to carry out a comprehensive research of technology and painting materials used in early and later western Tibetan Buddhist wall paintings as well as a comparative assessment with murals from other sites in the Western Himalayas. The study was based on extensive fieldwork and an integrated analytical approach comprising a wide range of non-destructive and micro-destructive methods. Answering the question of the coevality of paintings in the smaller temples with other original murals, the precise characterisation of binding media, the detection of the yellow dye gamboge and natural minerals posnjakite and brochantite identified for the first time in Himalayan murals, the clarification of technology of metal decoration, and the making of raised elements are some of the most exciting results which emerged from the research. 相似文献
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Debasis?GangulyEmail authorView authors OrcID profile Gareth?J.?F.?Jones Aarón?Ramírez-de-la-Cruz Gabriela?Ramírez-de-la-Rosa Esaú?Villatoro-Tello 《Information Retrieval》2018,21(1):1-23
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents. 相似文献
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