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31.
The purpose of this investigation was to examine the fluid dynamic characteristics of the two most commonly used oar blades: the Big Blade and the Macon. Scaled models of each blade, as well as a flat Big Blade, were tested in a water flume using a quasi-static method similar to that used in swimming and kayaking research. Measurement of the normal and tangential blade forces enabled lift and drag forces generated by the oar blades to be calculated over the full range of sweep angles observed during a rowing stroke. Lift and drag force coefficients were then calculated and compared between blades. The results showed that the Big Blade and Macon oar blades exhibited very similar characteristics. Hydraulic blade efficiency was not therefore found to be the reason for claims that the Big Blade could elicit a 2% improvement in performance over the Macon. The Big Blade was also shown to have similar characteristics to the flat plate when the angle of attack was below 90 degrees , despite significant increases in the lift coefficient when the angle of attack increased above 90 degrees . This result suggests that the Big Blade design may not be completely optimized over the whole stroke.  相似文献   
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The moral panic over the impact of so-called predatory publishers continues unabated. It is important, however, to resist the urge to simply join in this crusade without pausing to examine the assumptions upon which such concerns are based. It is often assumed that established journals are almost sacrosanct, and that their quality, secured by peer review, is established. It is also routinely presumed that such journals are immune to the lure of easy money in return for publication. Rather than looking at the deficits that may be apparent in the practices and products of predatory publishers, this commentary invites you to explore the weaknesses that have been exposed in traditional academic journals but are seldom discussed in the context of predatory publishing. The inherent message for health and medical services staff, researchers, academics, and students is, as always, to critically evaluate all sources of information, whatever their provenance.  相似文献   
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Many organizations have adopted a wide variety of approaches in introducing selected practices for achieving control of the quality of their products and services. Some of these piecemeal applications of the Quality Sciences have been successful–to varying degrees and for a time. However, the only approach that achieves long-term success is that requiring a complete cultural change in most organizations– involving a refocusing of all activities performed by everyone toward mutually intersupportive efforts to reach a common objective. In a word, a Quality System is required. In this paper, I have attempted to portray the basic considerations involved in developing and installing such a system. This is accomplished by describing some of the background of the system concept, certain of the internal and external features of a Quality System, and, to complete the picture, a semi-fictitious recital of the experiences of a company that has decided to embark on the Quality System journey.  相似文献   
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Journal of Cultural Economics - In the competitive, increasingly international music business, publishers are developing new ways to increase effectiveness and efficiency of the monetization of the...  相似文献   
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Fernandez  Frank  Baker  David P.  Fu  Yuan-Chih  Muñoz  Ismael G.  Ford  Karly Sarita 《Minerva》2021,59(1):79-98
Minerva - Over the course of the 20th century, unprecedented growth in scientific discovery was fueled by broad growth in the number of university-based scientists. During this period the American...  相似文献   
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<正>They already spent half a lifetime researching and promoting Chinese traditional music, and continue to do so today: Frank Kouwenhoven, a Dutch journalist, m...  相似文献   
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