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41.
Rossella Sacchetti Andrea Ceciliani Andrea Garulli Andrea Masotti Giuseppe Poletti Patrizia Beltrami 《Journal of sports sciences》2013,31(7):633-640
Abstract A cross-sectional study was carried out to analyse, through a limited number of fitness tests, the main conditioning and coordinative abilities in children aged 8–9 years, and their relationship with gender, anthropometric variables and physical activity habits. The height and weight of 256 boys and 241 girls were measured and information about physical activity habits was collected using a self-administered questionnaire. Physical performance was assessed by means of a few standardised tests: ‘sit & reach’, medicine-ball forward throw, standing long jump, 20 m running speed, and forward roll test. In both boys and girls, body weight and Body Mass Index (BMI) were positively correlated with the medicine-ball throw performances and negatively correlated for the standing long jump and speed tests, while no association was found with tests measuring back flexibility and total body coordination. Daily physical activity and participation in sport were not significantly correlated with body weight and BMI, but were positively associated with children's motor performance. The standardised fitness tests selected in the current study have been found to be suitable to identify fitness levels of primary school children. Thanks to their limited number and ease of measurement, they can be used in any school context to classify children and for monitoring the effects of targeted interventions promoting physical activity. 相似文献
42.
运用文献资料法、数据分析法,以欧洲足球五大联赛2017—2018赛季经营状况为载体,从职业足球俱乐部内部经营和市场环境两方面讨论和研究其市场治理的具体做法,借鉴五大联赛市场平稳有序和职业足球俱乐部可持续发展的经验,进而从我国国情及足球发展现状出发,结合五大联赛市场治理经验,探索中超联赛市场治理创新。研究认为:创新治理主体结构,形成“三位一体”的治理格局,明确中超联赛治理主体责任;创新职业足球市场治理体制,提高中超市场自治能力和水平;创新职业足球俱乐部内部治理体系, 创造职业足球俱乐部健康可持续发展生态;创新治理价值体系,打造足球产业经营全产业链,打造中超市场盈利模式。 相似文献
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44.
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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46.
Andrea L. Kavanaugh Debbie Denise Reese John M. Carroll Mary Beth Rosson 《The Information Society》2005,21(2):119-131
Communities with high levels of social capital are likely to have a higher quality of life than communities with low social capital. This is due to the greater ability of such communities to organize and mobilize effectively for collective action because they have high levels of social trust, dense social networks, and well-established norms of mutuality (the major features of social capital). Communities with “bridging” social capital (weak ties across groups) as well as “bonding” social capital (strong ties within groups) are the most effective in organizing for collective action. People who belong to multiple groups act as bridging ties. When people with bridging ties use communication media, such as the Internet, they enhance their capability to educate community members and to organize, as needed, for collective action. This article summarizes evidence from stratified household survey data in Blacksburg, VA, showing that people with weak (bridging) ties across groups have higher levels of community involvement, civic interest, and collective efficacy than people without bridging ties among groups. Moreover, heavy Internet users with bridging ties have higher social engagement, use the Internet for social purposes, and have been attending more local meetings and events since going online than heavy Internet users with no bridging ties. These findings may suggest that the Internet—in the hands of bridging individuals-is a tool for enhancing social relations and information exchange, and for increasing face-to-face interaction, all of which help to build both bonding and bridging social capital in communities. 相似文献
47.
Recently, there has been a heavy debate in the US about the government’s use of data mining in its fight against terrorism.
Privacy concerns in fact led the Congress to terminate the funding of TIA, a program for advanced information technology to
be used in the combat of terrorism. The arguments put forward in this debate, more specifically those found in the main report
and minority report by the TAPAC established by the Secretary of Defense to examine the TIA issue, will be analysed to trace
the deeper roots of this controversy. This analysis will in turn be used as a test case to examine the adequacy of the usual
theoretical frameworks for these kinds of issues, in particular the notion of privacy. Whereas the dominant theoretical framing
of the notion of privacy turns around access to information, most of the core arguments in the debate do not fit in this kind of framework. The basic disagreements in
the controversy are not about mere access, they involve both access and use. Furthermore, whereas the issue of access by itself refers to a more or less static situation, the real disagreements much
more concern the organisational dynamics of the use of information, the mechanisms in the organisation that control these
dynamics, and the awareness present within the organisation of the ‘social risks’ these dynamics represent. The bottom line
question is whether the assessment of these gives sufficient reason for trust. 相似文献
48.
This paper deals with intercultural aspects of privacy, particularly with regard to important differences between Japanese
and the Western views. This paper is based on our discussions with Rafael Capurro – a dialogue now represented by two separate
but closely interrelated articles. The companion paper is broadly focused on the cultural and historical backgrounds of the
concepts of privacy and individualism in “Western” worlds; our main theme focuses on different concepts of privacy in Japan
and their sources in related aspects of Japanese culture. The interrelationship between our two papers is apparent in our
taking up identical or similar topics in each paper. Reading our two papers in conjunction with each other will bring about
deeper and broader insights into the diverse values and worldviews of Japan and Western cultures that underlie concepts of
privacy that at a surface level appear to be similar 相似文献
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50.
This study is part of a larger research project at the Image Permanence Institute dedicated to digital print preservation issues – the Digital Print Preservation Portal (DP3). Previous DP3 studies determined that certain digital print types are prone to cracking and/or abrasion, and that factors such as low relative humidity, pollutants, and light increase the brittleness of the ink-receiving layer of some inkjet papers. The purpose of this investigation was to explore if light also increases the propensity of inkjet prints to abrade, and to examine the potential of framing glazings to mitigate light-induced physical damage (cracking and abrasion) by attenuating some portion of the UV spectrum. Inkjet papers and prints were subjected to xenon lighting (to simulate daylight through window glass) without glazing, or in sealed framing packages with plain framing glass (soda-lime) or UV filtering glass. Before and after light exposure, brittleness, and abrasion resistance were evaluated independently using two tests: ISO 18907 (Imaging materials – Photographic films and papers – Wedge test for brittleness) and a rub test utilizing a Sutherland® Rub Tester. In this study, exposure to light increased the cracking and/or abrasion tendency of some specimens. The use of UV filtering glass reduced this light-induced propensity in all cases. Plain glass protected all samples from at least one of these two types of surface damage, but was less effective than UV glass. Light-induced brittleness and sensitivity to abrasion were mostly, though not exclusively, caused by UV radiation. It was also seen that some prints may become brittle and/or prone to abrasion in the absence of image fade. Budgeting the amount of light these objects can be exposed to, protecting them from UV radiation, and handling prints with caution especially after exhibition, is essential in order to limit physical damage. 相似文献