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Word-learning skills of deaf preschoolers: the development of novel mapping and rapid word-learning strategies 总被引:2,自引:0,他引:2
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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Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to 30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications. 相似文献
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Rees Lewis Daniel G. Gerber Elizabeth M. Carlson Spencer E. Easterday Matthew W. 《Educational technology research and development : ETR & D》2019,67(4):953-982
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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Aaron L. Wallis David P. Gretz Jeffrey A. Rings Kiersten M. Eberle 《Journal of College Counseling》2019,22(2):125-137
This article examines the relationship between marijuana use and anxiety symptoms among college students, with a secondary focus on marijuana use and grade point average (GPA). A secondary analysis was conducted on data obtained from the American College Health Association–National College Health Assessment. Results indicated that marijuana use was negatively associated with GPA among students with current anxiety and no formal treatment. The relationships between these variables may be more complex than previously thought. 相似文献
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Sam Robertson Bart Spencer Nicole Back Damian Farrow 《Journal of sports sciences》2019,37(11):1280-1285
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