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Recognising the rise of an aging population and independent living among older adults, many governments and organisations have developed and promoted new technologies in the form of gerontechnologies to support the needs and enhance the well-being of older adults. However, the adoption of products using such technology remains modest among the aging population. This study introduces the notion of power in the form of power posing and examines its impact on new technology adoption, particularly gerontechnology, among older adults. Using an experimental approach on a sample of older adults exposed to an in-house near-field communication-enabled light system, the study finds that high-power poses have a greater and more positive impact on older adults’ perceived ease of use of, perceived usefulness of, and intentions to use gerontechnology than low-power poses. Implications, limitations, and future research directions are discussed.  相似文献   
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We propose an adaptive and energy-efficient TDMA-based MAC protocol that significantly reduces energy consumption in the network, while efficiently handling network traffic load variations and optimizing channel utilization through a timeslot stealing mechanism and a timeslot reassignment procedure. We have analytically derived the average delay performance of our MAC protocol, with and without the timeslot stealing mechanism. Our delay model, validated via simulations, shows that the timeslot stealing mechanism can substantially improve the protocol throughput in scenarios with varying and asymmetric traffic patterns. Evaluation results show that the timeslot reassignment procedure is efficient in handling the longer timescale changes in the traffic load, while the timeslot stealing mechanism is better in handling the shorter timescale changes in the traffic patterns.  相似文献   
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Multibody System Dynamics - Heretofore, the Serret–Frenet frame has been the ubiquitous choice for analyzing the elastic deformations of beam elements. It is well-known that this frame is...  相似文献   
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Motion segmentation and non-rigid structure from motion are two challenging computer vision problems that have attracted numerous research interests. While the previous works handle these two problems separately, we present a general motion segmentation framework in this paper for solving these two seemingly different problems in a unified manner. At the heart of our general motion segmentation framework is a model selection mechanism based on finding the minimal basis subspace representation, by seeking the joint sparse representation of the data matrix. However, such formulation is NP-hard and we solve the convex proxy instead. Unlike other compressive sensing related works, this convex proxy solution is insufficient for our problem. The convex relaxation artefacts and noise yield multiple subspace representations, making identification of the exact number of motion subspaces challenging. We solve for the right number of subspaces by transforming this problem into a Facility Location problem with global cost and solve the factor graph formulation using max product belief propagation message passing.  相似文献   
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The purpose of this research was to investigate the effect of practice teaching in Second Life on the change of preservice teachers’ teaching efficacy, and the difference of changes between individual teaching practice and collaborative teaching practice in their teaching efficacy. Participants were placed into the individual teaching practice or collaborative teaching practice group as a part of a teaching methods and educational technology course. Both groups completed practice teaching sessions twice in Second Life and an instrument adopted for measuring of pre-service teachers’ teaching efficacy beliefs was administered after each of three stages. The researcher collected data from both groups before the first practice teaching, after the first practice teaching session, and after the second session. Results from a Repeated Measure ANOVA indicated that the practice sessions influenced changes in participants’ personal teaching efficacy but not teaching outcome expectancy. In addition, the results indicated significant difference between groups on their personal teaching efficacy after the second practice session, but not on teaching outcome expectancy. The difference between the two groups is attributed to the different methods in preparing for the practice session, practicing the teaching, and the reflection methods posed to each group of participants. This research suggests that pre-service teachers can gain valuable teaching practice in Second Life, and furthermore that collaborative practice teaching is more effective way than individual approaches to practicing teaching.  相似文献   
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Detection-based pedestrian counting methods produce results of considerable accuracy in non-crowded scenes. However, the detection-based approach is dependent on the camera viewpoint. On the other hand, map-based pedestrian counting methods are performed by measuring features that do not require separate detection of each pedestrian in the scene. Thus, these methods are more effective especially in high crowd density. In this paper, we propose a hybrid map-based model that is a new directional pedestrian counting model. Our proposed model is composed of direction estimation module with classified foreground motion vectors, and pedestrian counting module with principal component analysis. Our contributions in this paper have two aspects. First, we present a directional moving pedestrian counting system that does not depend on object detection or tracking. Second, the number and major directions of pedestrian movements can be detected, by classifying foreground motion vectors. This representation is more powerful than simple features in terms of handling noise, and can count the moving pedestrians in images more accurately.

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Bulk unipolar diodes with a wide range of barrier heights have been made in hydrogenated amorphous silicon by ion implantation. The precise concentration of dopant atoms that can be obtained when implanting into an amorphous substrate leads to accurate barrier height control. Compared with the alternative unipolar device, the Schottky diode, these devices should provide uniform, high barrier diodes for photodetectors, and very low barrier diodes for low-power, unbiased, mixers and detectors  相似文献   
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