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61.
Education and Information Technologies - Digital learning increasingly makes use of realistic visualizations, although realism can be demanding for learners. Color coding is a popular way of...  相似文献   
62.
How can art museums use interpretive technology to engage visitors actively in new kinds of experiences with works of art? What are the best strategies for integrating technology into the visitor experience? In 2012, the Cleveland Museum of Art responded with Gallery One, an interactive art gallery that opened to stakeholders on December 12, and went through a six‐week testing period before its public opening on January 21, 2013. Gallery One drew from extensive audience research and was part of a major building and renovation project in which CMA reinstalled and reinterpreted the entire permanent collection in new and renovated gallery spaces. The end result was an innovative and robust blend of art, technology, design, and a unique user experience that emerged through the collaboration of staff across the museum and with outside consultants.  相似文献   
63.
Bryan Alexander described the digital environment that we live in, giving an extensive overview of the current state of interactive devices, particularly mobile devices, which are moving us beyond the personal computer. He covered recent major developments that have transformed the world in surprising ways in a rather short period of time. The world of apps is further expanding what these devices can do, also bringing with them more challenges to individual privacy. Gaming and augmented reality are becoming deeply embedded in much of what we do. Alexander laid out four possible futures that these contemporary developments could lead to.  相似文献   
64.
The benefits of peer collaboration on strategy use, metacognitive causal attribution, and recall were supported in an earlier study (Manion & Alexander, 1997). Following that study two primary questions remained: Would the observed benefits last beyond an immediate posttest, and would they last regardless of which strategy the children chose to use? The current investigation explores those questions. Thirty-one fourth-grade students from two public schools in Sydney, Australia, experienced either a peer-collaborative treatment condition or an individual task (control condition). A posttest was conducted 5.5 weeks later. As was the case in the original study, children in the treatment condition outperformed children in the control condition in strategy use, metacognitive understanding of strategy chosen, and recall gain. Benefits also sustained regardless of the strategy children chose to implement on the task. Most importantly, the benefits lasted after a period of over a month. Implications for future research are discussed.  相似文献   
65.
66.
Book reviews   总被引:1,自引:0,他引:1  
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67.
Perspectival Models and Theory Unification   总被引:1,自引:0,他引:1  
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68.
This paper presents a vertically positioned microfluidic system made of poly(dimethylsiloxane) (PDMS) and glass, which can be applied as a microbubble column (μBC) for biotechnological screening in suspension. In this μBC, microbubbles are produced in a cultivation chamber through an integrated nozzle structure. Thus, homogeneous suspension of biomass is achieved in the cultivation chamber without requiring additional mixing elements. Moreover, blockage due to produced carbon dioxide by the microorganisms—a problem predominant in common, horizontally positioned microbioreactors (MBRs)—is avoided, as the gas bubbles are released by buoyancy at the upper part of the microsystem. The patterned PDMS layer is based on an optimized two-lithographic process. Since the naturally hydrophobic PDMS causes problems for the sufficient production of microbubbles, a method based on polyelectrolyte multilayers is applied in order to allow continuous hydrophilization of the already bonded PDMS-glass-system. The μBC comprises various microelements, including stabilization of temperature, control of continuous bubble formation, and two optical configurations for measurement of optical density with two different sensitivities. In addition, the simple and robust application and handling of the μBC is achieved via a custom-made modular plug-in adapter. To validate the scalability from laboratory scale to microscale, and thus to demonstrate the successful application of the μBC as a screening instrument, a batch cultivation of Saccharomyces cerevisiae is performed in the μBC and compared to shake flask cultivation. Monitoring of the biomass growth in the μBC with the integrated online analytics resulted in a specific growth rate of 0.32 h−1, which is almost identical to the one achieved in the shake flask cultivation (0.31 h−1). Therefore, the validity of the μBC as an alternative screening tool compared to other conventional laboratory scale systems in bioprocess development is proven. In addition, vertically positioned microbioreactors show high potential in comparison to conventional screening tools, since they allow for high density of integrated online analytics and therefore minimize time and cost for screening and guarantee improved control and analysis of cultivation parameters.  相似文献   
69.
The field hockey hit is an important but poorly understood stroke. In this study, we investigated the planarity of the stickface motion during the downswing to better characterize the kinematics and to assess the suitability of planar pendulum models for simulating the hit. Thirteen experienced female field hockey players were filmed executing hits with a single approach step, and the kinematics of the centre of the stickface were measured. A method was developed for identifying how far back from impact the stickface motion was planar. Orthogonal regression was used to fit least-squares planes to the stickface path during sections of the downswing of varying length, with each section ending at impact. A section was considered planar if the root mean square residual between the stickface path and the fitted plane was less than 0.25% of the distance travelled by the stickface during that period. On average, the stickface motion was planar for the last 83 ± 12% of its downswing path, with the length of the planar section ranging from 1.85 m to 2.70 m. The suitability of a planar model for the stickface motion was supported, but further investigation of the stick and arm kinematics is warranted.  相似文献   
70.
In 219 recreational male runners, we investigated changes in body mass, total body water, haematocrit, plasma sodium concentration ([Na(+)]), and urine specific gravity as well as fluid intake during a 100-km ultra-marathon. The athletes lost 1.9 kg (s = 1.4) of body mass, equal to 2.5% (s = 1.8) of body mass (P < 0.001), 0.7 kg (s = 1.0) of predicted skeletal muscle mass (P < 0.001), 0.2 kg (s = 1.3) of predicted fat mass (P < 0.05), and 0.9 L (s = 1.6) of predicted total body water (P < 0.001). Haematocrit decreased (P < 0.001), urine specific gravity (P < 0.001), plasma volume (P < 0.05), and plasma [Na(+)] (P < 0.05) all increased. Change in body mass was related to running speed (r = -0.16, P < 0.05), change in plasma volume was associated with change in plasma [Na(+)] (r = -0.28, P < 0.0001), and change in body mass was related to both change in plasma [Na(+)] (r = -0.36) and change in plasma volume (r = 0.31) (P < 0.0001). The athletes consumed 0.65 L (s = 0.27) fluid per hour. Fluid intake was related to both running speed (r = 0.42, P < 0.0001) and change in body mass (r = 0.23, P = 0.0006), but not post-race plasma [Na(+)] or change in plasma [Na(+)] (P > 0.05). In conclusion, faster runners lost more body mass, runners lost more body mass when they drank less fluid, and faster runners drank more fluid than slower runners.  相似文献   
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