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21.
Suzana Matheus Pereira Caroline Ruschel Marcel Hubert Leandro Machado Helio Roesler Ricardo Jorge Fernandes 《Journal of sports sciences》2015,33(19):2006-2015
This study aimed to analyse the kinematic, kinetic and electromyographic characteristics of four front crawl flip turn technique variants. The variants distinguished from each other by differences in body position (i.e. dorsal, lateral, ventral) during rolling, wall support, pushing and gliding phases. Seventeen highly trained swimmers (17.9 ± 3.2 years old) participated in interventional sessions and performed three trials of each variant, being monitored with a 3-D video system, a force platform and an electromyography (EMG) system. Studied variables: rolling time and distance, wall support time, push-off time, peak force and horizontal impulse at wall support and push-off, centre of mass horizontal velocity at the end of the push-off, gliding time, centre of mass depth, distance, average and final velocity during gliding, total turn time and electrical activity of Gastrocnemius Medialis, Tibialis Anterior, Biceps Femoris and Vastus Lateralis muscles. Depending on the variant, total turn time ranged from 2.37 ± 0.32 to 2.43 ± 0.33 s, push-off force from 1.86 ± 0.33 to 1.92 ± 0.26 BW and centre of mass velocity during gliding from 1.78 ± 0.21 to 1.94 ± 0.22 m · s?1. The variants were not distinguishable in terms of kinematical, kinetic and EMG parameters during the rolling, wall support, pushing and gliding phases. 相似文献
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Nuria Calet Nicolás Gutiérrez-Palma Ian C. Simpson M. Carmen González-Trujillo Sylvia Defior 《Scientific Studies of Reading》2015,19(1):51-71
Previous studies implicate suprasegmental phonology in reading acquisition. However, little is known about how suprasegmental sensitivity develops or how it contributes to reading. Here, 130 Spanish primary-school children participated in this 2-year longitudinal study. Nonlinguistic rhythm, lexical-stress sensitivity and metrical-stress sensitivity, along with phonological awareness, vocabulary, nonverbal intelligence, and reading aloud, were assessed on five occasions. Results suggest that prosody abilities have different developmental trajectories and that prosody explains unique variance in reading beyond that explained by other factors. There was some evidence that the contribution of each prosody skill occurred at different phases in reading development. Nonlinguistic rhythm, lexical-stress sensitivity, and metrical-stress sensitivity assessed at the end of kindergarten, the start of Grade 1, and the end of Grade 1, respectively, predicted reading performance 6 months later. Nevertheless, sample size and reliability temper the conclusions that can be made. The implications of prosody skills for literacy development are discussed. 相似文献
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Costa Ricardo V Fernández-Jardon Fernández Carlos Figueroa Dorrego Pedro 《知识管理研究与实践》2014,12(3):322-338
Knowledge Management Research & Practice - The general purpose of this research is to study interaction effects between intangible assets and product innovation. More specifically, the authors... 相似文献
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Manuel Perea Victoria Panadero Carmen Moret-Tatay Pablo Gómez 《Learning and Instruction》2012,22(6):420-430
Recent research has demonstrated that slight increases of inter-letter spacing have a positive impact on skilled readers' recognition of visually presented words. In the present study, we examined whether this effect generalises to young normal readers and readers with developmental dyslexia, and whether increased inter-letter spacing affects the reading times and comprehension of a short text. To that end, we conducted a series of lexical decision and continuous reading experiments in which words were presented with the default settings or with a small increase in inter-letter spacing. Increased spacing produced shorter word identification times not only with adult skilled readers (Experiment 1), but also with young normal readers (Grade 2 and Grade 4 children; Experiment 2) and, even to a larger degree, with readers with dyslexia (Experiments 3 and 4). These experiments suggest that slight increases in inter-letter spacing would improve the readability of texts aimed at children, especially those with dyslexia. 相似文献
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This work is devoted to the study of symmetric control systems. It establishes a relation between internal symmetry and external one for a linear invariant control system having n real simple poles. The symmetric stabilization problem is studied using a symmetric feedback gain such that the output control stabilizes the closed-loop system. A necessary and sufficient condition is given to solve this stabilization problem for a symmetric control system (A,B,C) and a generalized symmetric control system (E,A,B,C). 相似文献
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The journal impact factor (JIF) is the average of the number of citations of the papers published in a journal, calculated according to a specific formula; it is extensively used for the evaluation of research and researchers. The method assumes that all papers in a journal have the same scientific merit, which is measured by the JIF of the publishing journal. This implies that the number of citations measures scientific merits but the JIF does not evaluate each individual paper by its own number of citations. Therefore, in the comparative evaluation of two papers, the use of the JIF implies a risk of failure, which occurs when a paper in the journal with the lower JIF is compared to another with fewer citations in the journal with the higher JIF. To quantify this risk of failure, this study calculates the failure probabilities, taking advantage of the lognormal distribution of citations. In two journals whose JIFs are ten-fold different, the failure probability is low. However, in most cases when two papers are compared, the JIFs of the journals are not so different. Then, the failure probability can be close to 0.5, which is equivalent to evaluating by coin flipping. 相似文献
30.
Ricardo Colomo-PalaciosAuthor VitaeEduardo FernandesAuthor Vitae Pedro Soto-AcostaAuthor Vitae Marc SabbaghAuthor Vitae 《International Journal of Information Management》2011,31(4):395-399
Software must evolve in order to adapt to new demands and scenarios. In the case of packaged software that can be customized, this evolution implies the maintenance of both out-of-the-box and customized functionality alike. New user interface technologies provide a way to interact with applications that software vendors are forced to incorporate in order to meet new user and market requirements. Packaged software vendors are facing software evolution processes in order to attract more customers and conserve the existing ones. This case analysis describes the evolution of packaged software, Meta4 PeopleNet, towards the addiction of Rich Internet Applications features to a Human and Intellectual Capital Management tool. The findings and lessons learned presented in this case study provide useful insights for packaged software vendors facing software product evolution. 相似文献