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51.
Concepts of data visualization are explored using statistics educational fun items and illustrated by sharing results from the experiment we conducted on cartoon captions.  相似文献   
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Finite-time stability involves dynamical systems whose trajectories converge to an equilibrium state in finite time. In this paper, we consider a general class of fully actuated mechanical systems described by Euler–Lagrange dynamics and the class of underactuated systems represented by mobile robot dynamics that are required to reach and maintain the desired trajectory in finite time. An approach known as the terminal sliding mode control (TSMC) involves non-smooth sliding surfaces such that, while on the sliding surface, the error states converge to the origin in finite time thus ensuring finite-time tracking. The main advantage of this control scheme is in fast converging times without excessive control effort. Such controllers are known to have singularities in some parts of the state space and, in this paper, we propose a method of partitioning the state space into two regions where the TSMC is bounded and its complement. We show that the region of bounded TSMC is invariant and design an auxiliary sliding mode controller predicated on linear smooth sliding surface for the initial conditions outside this region. Furthermore, we extend these results to address TSMC for underactuated systems characterized by the mobile robot dynamics. We demonstrate the efficacy of our approach by implementing it for a scenario when multiple dynamic agents are required to move in a fixed formation with respect to the formation leader. Finally, we validate our results experimentally using a wheeled mobile robot platform.  相似文献   
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We evaluate feedback methods for oral presentations used in training non-quantitative research skills (literature review and various associated tasks). Training is provided through a credit-bearing module taught to MSc students of banking, economics and finance in the UK. Monitoring oral presentations and providing ‘best practice’ feedback is very resource-intensive. Do we withdraw oral presentations from the module, because best feedback practice is prohibitively expensive in a world of limited resources, or choose a second-best alternative? To what extent might the latter compromise intended learning outcomes? We used the same provision of video feedback for all students but used two verbal feedback regimes. For one regime, we decreased the amount of verbal feedback and increased the number of presentations. The impact was measured by academic outcome, rating scales and questionnaire. Overall satisfaction with the module was very high for both feedback regimes, and there were no statistically significant differences between regimes, suggesting that less resource-intensive methods need not compromise learning outcomes.  相似文献   
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This study used eye-tracking methodology to assess audiovisual speech perception in 26 children ranging in age from 5 to 15 years, half with autism spectrum disorders (ASD) and half with typical development. Given the characteristic reduction in gaze to the faces of others in children with ASD, it was hypothesized that they would show reduced influence of visual information on heard speech. Responses were compared on a set of auditory, visual, and audiovisual speech perception tasks. Even when fixated on the face of the speaker, children with ASD were less visually influenced than typical development controls. This indicates fundamental differences in the processing of audiovisual speech in children with ASD, which may contribute to their language and communication impairments.  相似文献   
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In the current experiment, we examined optimal focus for novices during a movement sequence in which performance was measured on accurate movement form/technique. A novel gymnastics routine was practiced under either an internal skill-relevant, internal skill-irrelevant, external, or no attention focus. Retention and transfer tests were then completed. During acquisition, adopting an internal irrelevant focus significantly improved performance, whereas an external focus degraded performance. There were no significant group differences in the retention and transfer tests. This suggests that learning of movement form/technique did not benefit from a specific focus of attention. The results are interpreted via an attentional capacity viewpoint and the notion that form tasks do not always contain obvious movement effects central to common coding and the constrained action hypothesis.  相似文献   
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Educational technology research and development - Captions play a major role in making educational videos accessible to all and are known to benefit a wide range of learners. However, many...  相似文献   
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