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ABSTRACT

This 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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Gordon  R. S.  Franklin  K. L.  Baker  J.  Davies  B. 《Sports Engineering》2004,7(3):131-138
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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The problem of student indiscipline is an issue of concern for teachers and parents around the world. Teachers need to maintain student discipline and for them to do so it is important that they also understand the nature of discipline problems. This study, by Lawrence Kofi Ametepee, who is studying for a PhD in special education, Morgan Chitiyo, board certified behaviour analyst and Assistant Professor of Special Education, both at Southern Illinois University, Carbondale, USA, and Susan Abu, who is currently a graduate student in the Department of Women's Studies at Texas Women's University, was designed to examine the nature and perceived causes of student indiscipline in Zimbabwean secondary schools. The authors anticipate that such an examination will promote teachers’, parents’ and policy makers’ understanding of student indiscipline, which will, in turn, enhance disciplinary policies and practices, making schools safer for all students and more effective in their role as educational and socialising agents.  相似文献   
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