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Word-learning skills of 19 deaf/hard-of-hearing preschoolers were assessed by observing their ability to learn new words in two contexts. The first context required the use of a novel mapping strategy (i.e., making the inference that a novel word refers to a novel object) to learn the new words. The second context assessed the ability to learn new words after minimal exposure when reference was explicitly established. The children displayed three levels of word-learning skills. Eleven children learned words in both contexts. Five were able to learn new words rapidly only when reference was explicitly established. Two children did not learn new words rapidly in either context. The latter seven children were followed longitudinally. All children eventually acquired the ability to learn new words in both contexts. The deaf children's word-learning abilities were related to the size of their vocabularies. The present study suggests that word-learning strategies are acquired even when children are severely delayed in their language development and they learn language in an atypical environment.  相似文献   
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Educational technology research and development - Authentic project-based learning (APBL) is a highly effective way for instructors to help students learn disciplinary skills, modes of thinking,...  相似文献   
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Body position is known to alter power production and affect cycling performance. The aim of this study was to compare mechanical power output in two riding positions, and to calculate the effects on critical power (CP) and W′ estimates. Seven trained cyclists completed three peak power output efforts and three fixed-duration trial (3-, 5- and 12-min) riding with their hands on the brake lever hoods (BLH), or in a time trial position (TTP). A repeated-measures analysis of variance showed that mean power output during the 5-min trial was significantly different between BLH and TTP positions, resulting in a significantly lower estimate of CP, but not W′, for the TTP trial. In addition, TTP decreased the performance during each trial and increased the percentage difference between BLH and TTP with greater trial duration. There were no differences in pedal cadence or heart rate during the 3-min trial; however, TTP results for the 12-min trial showed a significant fall in pedal cadence and a significant rise in heart rate. The findings suggest that cycling position affects power output and influences consequent CP values. Therefore, cyclists and coaches should consider the cycling position used when calculating CP.  相似文献   
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Representative learning design provides a framework for the extent to which practice simulates key elements of a performance setting. Improving both the measurement and analysis of representative learning design would allow for the refinement of sports training environments that seek to replicate competition conditions and provide additional context to the evaluation of athlete performance. Using rule induction, this study aimed to develop working models for the determination of high frequency, representative events in Australian Rules football kicking. A sample of 9005 kicks from the 2015 Australian Football League season were categorised and analysed according to the following constraints: type of pressure, kick distance, possession source, time in possession, velocity and kick target. The Apriori algorithm was used to develop two models. The first consisted of 10 rules containing the most commonly occurring constraint sets occurring during the kick in AF, with support values ranging from 0.15 to 0.22. None of the rules contained more than three constraints and confidence values ranged from 0.63 to 0.84. The second model considered ineffective and effective kick outcomes and displayed 70% classification accuracy. This research provides a measurement approach to determine the degree of representativeness of sports practice and is directly applicable to various team sports.  相似文献   
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A study is made of separability conditions for the Helmholtz and Laplace equations. Attention is confined to the most useful case for physical applications; namely,
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(a) The coordinate system is either cylindrical or it has rotational symmetry, and  相似文献   
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The purpose of the paper has been to present simplified methods that will expedite the calculation of ceiling lighting (Type II). Approximate formulas have been given, which allow ordinary slide-rule calculations to be made very easily for the usual range of variables. Only with rooms having very high domance (or perhaps with extraordinarily high floor reflectance) are the complicated equations of the previous paper (1) needed. These approximate formulas can be represented also by alignment charts, Figs. 2 to 5, which further simplify the work.Either the formulas or the charts may be used to investigate the effect of a change in ?1, ?2, or ?3. However, if reflectances are standardized at recommended values, other methods are possible.In particular, one may use graphs (Fig. 6) or a slide-rule (Figs. 7 and 8). The method of calculation chosen for a specific problem will depend on the problem and on the preferences of the designer. The previous equations and tables (3) may always be used; but in most cases, time can be saved by employing the short-cuts given in the present paper.  相似文献   
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Previous interflectance tables have dealt principally with three basic types of lighting (Types I, II, and III). The present paper extends the scope of the interflection method by showing how it can be applied to rooms lighted by hanging luminaires. It is found that most cases arising in practice can be covered by six canonic distributions. The effect of mounting height is handled by means of a simple equation.  相似文献   
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