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Helen S. Du Samuel K.W. Chu Gary E. Gorman Felix L.C. Siu 《Library & information science research》2014
Three groups of social bookmarking users, namely experienced users, users with moderate level of experience, and novice users, were investigated, in terms of their reported tagging behaviors, perceived usefulness of social bookmarking in information discovery and management, and perceived usefulness of the bookmarking features provided. Based on the empirical analysis of the Connotea users, who are primarily in academia, the study shows that experienced academic users generally prefer to use social bookmarking while moderately experienced and novice users still prefer to use the traditional bookmarking methods, such as creating and using bookmarks on a dedicated computer. Experienced academic users were also found to create more tags per bookmark comparing to the other two groups. Most novice academic users, however, only created one tag per bookmark, which just met Connotea's minimum requirement. Surprisingly different from the collaborative design nature of the social bookmarking systems, the study finds that our participants, particularly experienced academic users, prefer to create and use their own bookmarks rather than sharing bookmarks created by others. In fact, experienced users have significantly higher frequency (once every two weeks) of creating bookmarks than the other two groups (once a month or less). In addition, website design features and functions, such as automatic collection of bibliographic information, are regarded by all participants as helpful for information discovery. The in-depth examination and discussion of the opinions of Connotea users may be useful for further improvement of the design features and usage applications, particularly for academic social bookmarking websites. The results may also have potential implications to the future development of social bookmarking services in general. 相似文献
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C.D. Tuska 《Journal of The Franklin Institute》1944,237(2):83-102
The foregoing notes trace the history of the measurement of the propagation times of radio waves as a means for determining distance. While the reader may feel that undue emphasis has been placed upon the KHL height measurements, a survey of the literature will show that only a small proportion of the reported observations have been cited here. Out of the hundreds of published articles on KHL height measurements, the writer has endeavored to select those which present the step-by-step improvements in the methods and apparatus. In the period just prior to the War, the United States Patents offered the principal means for tracing the development of the art. In the war period the notes are necessarily incomplete because of the scarcity of publications; this is no doubt due to secrecy conditions. 相似文献
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Abstract A study was made of the relationship of physique and developmental level, determined by use of the Wetzel Grid, to performance of junior high boys on four fitness tests: pull-ups, 50-yd. dash, standing broad jump, and softball throw. Subjects of different physique groups (heavy, medium, and thin) who were alike developmentally (accelerated, normal, and retarded) differed more markedly in performance than did subjects of different developmental levels who were alike with regard to physique. Subjects who were medium in physique and normal in development were the best performers. Subjects of heavy physique (many overweight) were the poorest performers. This would seem to indicate the need for a restudy of classification methods, particularly when norms are to be used for evaluating performance. 相似文献