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81.
Elaine M. Huang Elizabeth D. Mynatt Jay P. Trimble 《Personal and Ubiquitous Computing》2007,11(7):537-547
Large interactive displays for supporting workgroup collaboration comprise a growing area of ubiquitous computing research
and many such systems have been designed and deployed in laboratory studies and research settings. Such displays face difficulties
in real-world deployments, as they are often supplemental technologies as opposed to primary tools for work activities. In
this work, we investigate the integration and uptake of the NASA MERBoards, shared interactive displays that were deployed
to support science tasks in the Mars Exploration Rover (MER) missions. We examine the hurdles to adoption imposed specifically
by the real-world circumstances of the deployment that were external to the design of the system, and explain how these concerns
apply to the general deployment of shared ubicomp technologies in the real world. 相似文献
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Elaine Y. Chan Author Vitae Author Vitae Michael K. Ng Author Vitae Joshua Z. Huang Author Vitae 《Pattern recognition》2004,37(5):943-952
One of the main problems in cluster analysis is the weighting of attributes so as to discover structures that may be present. By using weighted dissimilarity measures for objects, a new approach is developed, which allows the use of the k-means-type paradigm to efficiently cluster large data sets. The optimization algorithm is presented and the effectiveness of the algorithm is demonstrated with both synthetic and real data sets. 相似文献
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Rasmussen Carmen; Ho Elaine; Nicoladis Elena; Leung Joyce; Bisanz Jeffrey 《Canadian Metallurgical Quarterly》2006,60(1):60
Chinese-speaking children have been shown to have an advantage over English-speaking children in a variety of mathematical areas, including counting. One possible explanation for the advantage in counting is that the Chinese number-naming system is relatively transparent, compared to English, in that number names typically are directly indicative of base-10 structure (e.g., 12 is named "ten-two" rather than "twelve"). To determine whether the transparency of the Chinese number-naming system influences counting in bilingual children, we tested 25 Chinese-English bilingual children between the ages of 3 and 5 years, both in English and in Chinese. Children were asked to count as high as they could (abstract counting) and also to count objects in small, medium, and large arrays (object counting). No evidence was found for transparency or for transfer from one language to the other. Instead, relative proficiency in the two languages influenced counting skill. These results are discussed in terms of linguistic and cultural variables that might account for cross-linguistic differences in counting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
3G时代是移动多媒体时代,但是移动多媒体时代并不会等着3G的来临才出现,全球的移动运营商已在2.5G网络上提供移动内容服务并在应对由内容计费带来的新挑战。明确了由于移动内容服务在移动网络中的发展给计费模式带来的挑战,并讨论了计费模式在过渡期的发展,其中还介绍了一些欧洲运营商的经验:它们正面临的问题以及采取的应对方法。 相似文献
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Vaughan Elaine; Anderson Craig; Agran Phyllis; Winn Diane 《Canadian Metallurgical Quarterly》2004,23(3):289
Interview data from 100 lower income Hispanic and 50 White mothers from a nutritional service clinic extended prior research on cultural differences in the risk for unintentional pediatric injuries. Group differences were expected in reported injury incidence and in the prevalence and impact of contributing factors. As predicted, White mothers reported more injuries for a young child, and among Hispanic mothers, English language preference and use were associated with more reported injuries. Hierarchical regression analysis revealed that risky behaviors, mother's judgment about child compliance, and stressful life events were better predictors of injuries than housing quality, but among Hispanics, the impact of certain factors (e.g.. child temperament) was qualified by mother's acculturation level. Stress and child temperament explained injury differences between more- and less-acculturated Hispanic families but only partially accounted for differences between White mothers and less-acculturated Hispanics. Pediatric injury risk and protective factors seemed to operate in concert with cultural processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
The relationship among self-concept, self-efficacy, and performance in mathematics was examined among 416 high school students. Participants completed a questionnaire assessing mathematics self-concept and mathematics self-efficacy. Performance was assessed using end-of-term exam results in mathematics. Confirmatory factor analyses supported the existence of two self-concept components--a competency component and an affective component. Self-efficacy items and the competency items of self-concept also loaded on a single factor. Social comparison information was equally influential in the formation of each construct. Self-efficacy beliefs, however, were identified as most highly related with performance in mathematics and percentages. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献