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1.
ABSTRACT The concept of digital game-based learning (DGBL) evolves rapidly together with technological enhancements of virtual reality (VR) and smart phones. However, the mental workload (MWL) that VR-training applications demand and motivational qualities originating from user experience (UX) should be identified in order to create effective and enjoyable training/learning challenges that fit with individual users’ capabilities. This study examined the effects of reality-based interaction (RBI) and VR on measures of student motivation and MWL, in a mental arithmetic game for secondary school pupils. In a randomised controlled trial with sixty school children, a mental arithmetic game was tested with three different interaction and two different presentation methods – VR RBI, VR head-mounted-display tapping and tablet flick-gesture. Results found a significant effect of RBI on MWL but no differences in enjoyment of training were found between VR-experience and tablet training-experience. In fact, adding the gaming-context to the mental arithmetic task created an enjoyable, motivating experience regardless of presentation or interaction-style. 相似文献
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Jost John T.; Glaser Jack; Kruglanski Arie W.; Sulloway Frank J. 《Canadian Metallurgical Quarterly》2003,129(3):383
A meta-analysis by J. T. Jost, J. Glaser, A. W. Kruglanski, and F. J. Sulloway (2003) concluded that political conservatism is partially motivated by the management of uncertainty and threat. In this reply to J. Greenberg and E. Jonas (2003), conceptual issues are clarified, numerous political anomalies are explained, and alleged counterexamples are incorporated with a dynamic model that takes into account differences between "young" and "old" movements. Studies directly pitting the rigidity-of-the-right hypothesis against the ideological extremity hypothesis demonstrate strong support for the former. Medium to large effect sizes describe relations between political conservatism and dogmatism and intolerance of ambiguity; lack of openness to experience; uncertainty avoidance; personal needs for order, structure, and closure; fear of death; and system threat. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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It was hypothesized that exposure to complementary representations of the poor as happier and more honest than the rich would lead to increased support for the status quo. In Study 1, exposure to "poor but happy" and "rich but miserable" stereotype exemplars led people to score higher on a general measure of system justification, compared with people who were exposed to noncomplementary exemplars. Study 2 replicated this effect with "poor but honest" and "rich but dishonest" complementary stereotypes. In Studies 3 and 4, exposure to noncomplementary stereotype exemplars implicitly activated justice concerns, as indicated by faster reaction times to justice-related than neutral words in a lexical decision task. Evidence also suggested that the Protestant work ethic may moderate the effects of stereotype exposure on explicit system justification (but not implicit activation). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The selenisation of the thin film precursors indium, Cu-In and Cu-In-Ga has been studied by in-situ X-ray diffraction. The influence of sodium doping on the kinetics of the solid-state reactions observed agrees with the predictions derived from a phenomenological model presented earlier. In this model a layer of sodium polyselenide is assumed to form at the surface of the precursor, or around each crystal grain. This layer might be responsible for impeded ion exchange in certain solid-state reactions. 相似文献
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Yueming Wang Brian Van Devener Xiaolong Li Jost O. L. Wendt 《Aerosol science and technology》2019,53(7):783-792
Ultrafine ash particles play an important role in establishing a sticky inner deposit layer on heat transfer surface for power plants, but it is still unclear whether a thin surface alkali coating on these ultrafine particles might control this deposition behavior. In this research, we used a high resolution FE-TEM/STEM equipped with twin SDD EDX detectors for high X-ray detection efficiency, to determine the presence and absence of surface enrichment of alkali metals on ultrafine solid fuel ash samples that had low bulk alkali compositions but high deposition rates. Results from two types of combustion generated nano-sized ash particles are presented. One was from the oxy-combustion of pulverized bituminous coal, the other from oxy-combustion of pulverized rice husks, both being burned in a 100?kW rated down-flow laboratory combustor. Elemental mapping results from STEM/EDX uncovered some surface enrichment of alkali metals in ultrafine ash particles, where it existed, as it did for combustion of rice husks. However, it was not able to discern similar alkali metal surface enrichment for the bituminous coal ultrafines that had resulted in even higher deposition rates. Since deposition rates from both of these cases lie on the same correlation with PM1, one can conclude that although surface enrichment of alkali metals is present for some ~100?nm particles, it is not a prerequisite to achieve high inner surface deposition rates. This is in contrast to prevailing theories that point to alkali metals as “bad actors” as far as the sticky inner deposition rate is concerned.
Copyright © 2019 American Association for Aerosol Research 相似文献
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Liquid nitrile rubber, hyperbranched polyester, and core/shell rubber particles of various functionality, namely, vinyl, carboxyl, and epoxy, were added up to 20 wt % to a bisphenol‐A‐based vinylester–urethane hybrid (VEUH) resin to improve its toughness. The toughness was characterized by the fracture toughness (Kc) and energy (Gc) determined on compact tensile (CT) specimens at ambient temperature. Toughness improvement in VEUH was mostly achieved when the modifiers reacted with the secondary hydroxyl groups of the bismethacryloxy vinyl ester resin and with the isocyanate of the polyisocyanate compound, instead of participating in the free‐radical crosslinking via styrene copolymerization. Thus, incorporation of carboxyl‐terminated liquid nitrile rubber (CTBN) yielded the highest toughness upgrade with at least a 20 wt % modifier content. It was, however, accompanied by a reduction in both the stiffness and glass transition temperature (Tg) of the VEUH resin. Albeit functionalized (epoxy and vinyl, respectively) hyperbranched polymers were less efficient toughness modifiers than was CTBN, they showed no adverse effect on the stiffness and Tg. Use of core/shell modifiers did not result in toughness improvement. The above changes in the toughness response were traced to the morphology assessed by dynamic mechanical thermal analysis (DMTA) and fractographic inspection of the fracture surface of broken CT specimens. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 672–680, 2002; DOI 10.1002/app.10392 相似文献
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Vinylester/epoxy (VE/EP)‐based thermosets of interpenetrating network (IPN) structures were produced by using a VE resin (bismethacryloxy derivative of a bisphenol A–type EP resin) with aliphatic (Al‐EP) and cycloaliphatic (Cal‐EP) EP resins. Curing of the EP resins occurred either with an aliphatic (Al‐Am) or cycloaliphatic diamine compound (Cal‐Am). Dynamic mechanical thermal analysis (DMTA) and atomic force microscopy (AFM) suggested the presence of an interpenetrating network (IPN) in the resulting thermosets. Fracture toughness (Kc) and fracture energy (Gc) were used as the toughness characterization parameters of the linear elastic fracture mechanics. Unexpectedly high Kc and Gc data were found for the systems containing cyclohexylene units in the EP network, such as VE/Al‐EP+Cal‐Am and VE/Cal‐EP+Al‐Am. This was attributed to the beneficial effects of the conformational changes of the cyclohexylene linkages (chair/boat), which were closely analogous to those in some thermoplastic copolyesters. The failure mode of the VE/EP thermoset combinations was studied in scanning electron microscopy (SEM) and discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2124–2131, 2003 相似文献
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The goal of this project is to build a miniaturized, user-friendly cytometry setup (Datta et al. in Microfluidic platform for education and research. COMS, Baton Rouge, 2008; Frische et al. in Development of an miniaturized flow cytometry setup for visual cell inspection and sorting. Baton Rouge, Project Report, 2008) by combining a customized, microfluidic device with visual microscope inspection to detect and extract specific cells from a continuous sample flow. We developed a cytological tool, based on the Coulter particle counter principle, using a microelectrode array patterned on a borosilicate glass chip as electrical detection set-up which is fully embedded into a polymeric multi-layer microfluidic stack. The detection takes place between pairs of coplanar Cr/Au microelectrodes by sensing an impedance change caused by particles continuously carried within a microfluidic channel across the detection area under laminar flow conditions. A wide frequency range available for counting provides information on cell size, membrane capacitance, cytoplasm conductivity and is potentially of interest for in-depth cell diagnostic e.g. to detect damaged or cancerous cells and select them for extraction and further in-depth analysis. 相似文献