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Sports Engineering - A Monark cycle ergometer is a device globally used in physiological studies to measure the work and energy levels of exercising humans. In this paper a rope-braked cycle... 相似文献
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Andy Horbal 《The Journal of Academic Librarianship》2018,44(2):179-189
Although a substantial majority of academic libraries now provide streaming video, the literature contains few studies which focus on how such resources are used. This article presents the results of a qualitative research study consisting of in-depth interviews with 18 instructors who use of one category of streaming video resources, educational videos, which are important because they are sold a higher price than most individuals can afford, and thus are typically only available to instructors through the library. The study's main findings are that instructors think educational streaming video resources compare favorably to commercial and non-streaming alternatives in most respects and use them whenever possible, that the primary benefit of these resources is to facilitate better use of limited class time by enabling instructors to assign videos as outside-of-class viewing, and that the library is not the primary means instructors use to discover new educational streaming video resources. Additional insights are provided into factors that academic libraries should consider when deciding which resources to invest in, which acquisition models to pursue, and what marketing strategies to employ to ensure maximum usage. 相似文献
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Vortices are whirling disturbances, commonly found in nature, ranging from tremendously small scales in Bose-Einstein condensations to cosmologically colossal scales in spiral galaxies. An optical vortex, generally associated with a spiral phase, can carry orbital angular momentum (OAM). The optical OAM can either be in the longitudinal direction if the spiral phase twists in the spatial domain or in the transverse direction if the phase rotates in the spatiotemporal domain. In this article, we demonstrate the intersection of spatiotemporal vortices and spatial vortices in a wave packet. As a result of this intersection, the wave packet hosts a tilted OAM that provides an additional degree of freedom to the applications that harness the OAM of photons. 相似文献
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