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Megan K. Schraedley Hamilton Bean Sarah E. Dempsey Mohan J. Dutta Kathleen P. Hunt Sonia R. Ivancic 《Journal of Applied Communication Research》2020,48(2):166-185
ABSTRACTThis forum brings together food, (in)security, and communication. The authors participating in this forum center communication as both process and tool for understanding, mitigating, and making meaning of food (in)security. The nine authors together discuss the role of communication in food (in)security, the central challenges for scholars and practitioners working on food (in)security, and the creative possibilities and impacts influencing the future of food (in)security. The forum produces a call for applied scholars to re-imagine communication frameworks in order to make meaningful differences in their communities. 相似文献
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Measuring Search Engine Quality 总被引:12,自引:3,他引:9
The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures. 相似文献
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Children with spelling deficits demonstrate significant difficulty using inflectional morphology in their writing. This study investigated whether phonological deficits account for these pronounced difficulties or if they are more accurately explained by limitations in morphological or orthographic awareness. Twenty–six 11—13–year–old children with spelling deficits, 31 younger spelling–level–matched children, and 31 age–matched children were asked to spell a series of verbs with past tense and progressive markers in dictated sentences and in list form. Performance on spelling tasks was compared to performance on phonological, morphological, and orthographic awareness tasks. Results suggest that children with spelling deficits have significant difficulty including inflections as well as spelling inflections and base words. Difficulty was most pronounced in a sentence context. Ability to spell inflectional forms was related to variation in morphological awareness in children with spelling deficits and to variation in orthographic awareness in spelling–level–matched children. 相似文献
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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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Development of maximal oxygen uptake in young elite male cross-country skiers: a longitudinal study.
F Ingjer 《Journal of sports sciences》1992,10(1):49-63
The aim of this study was to investigate the effects of extensive endurance training (15-25 h per week) on the development of maximal oxygen uptake (VO2 max) in boys from puberty. Maximal oxygen uptake was measured a number of times each year from the age of puberty and for the next 6-9 years in seven young male elite cross-country skiers. Mean VO2 max was measured as 76.3 and 80.1 ml kg-1 min-1 at the ages of 14 and 15 years respectively. Despite the fast rate of growth during puberty, maximal aerobic power showed seasonal variations from the age of 14, reaching a plateau at the age of 15, whereas VO2 max (ml kg-2/3 min-1) increased continuously. It is concluded that, during puberty, boys probably attain significant increases in VO2 max when appropriate amounts of endurance training are undertaken. 相似文献
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