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M A Cahan 《Medical reference services quarterly》1989,8(4):61-79
The latest release of GRATEFUL MED offers medical libraries an opportunity to monitor searching patterns of end users searching the databases of the National Library of Medicine (NLM). A GRATEFUL MED use log records information from each search session. Analysis of the log from a recent beta test program at the Welch Medical Library indicates that most NLM searches occur in the MEDLINE database. Moreover, the study reveals that searchers overlook many user-friendly features of the program. Evaluation of the use log suggests changes for future versions of the program. 相似文献
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The displacement of the golf ball struck by a driving club is affected by several player characteristics and equipment parameters and their interrelationships. Some modelling and simulation studies have shown a relationship between shaft length and clubhead speed, supported by a few experimental studies. The aim of the present study was to examine the relationship between driver length and ball launch conditions in an indoor test facility using a ball launch monitor. Nine males considered to be skilled golfers participated in the study. Four driving clubs of total length 117, 119, 124, and 132 cm were assembled from commercially available components and were used to strike golf shots while initial ball velocity, backspin rate, and launch angles were measured. Statistical analysis identified a significant difference in initial launch speed due to club length, a significant difference between participants, but no difference between the trials for a given golfer. A positive trend was noted between backspin and launch angle for all four clubs, and significant inverse associations between initial launch speed and backspin rate and launch angle. However, the combined launch conditions associated with increasing length were not considered optimal, with uncontrolled swingweight and moment of inertia effects considered to be limiting factors. 相似文献
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