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131.
A mathematical model relating power output of rower to stroke rate on an ergometer (the Concept II Indoor Rower TM, Model
C) is studied. The model is used to analyse the ergometer performance of a particular rower. It is determined that he can
be more efficient (i.e. decrease power output while maintaining fixed velocity) by decreasing stroke rate, but at the expense
of increasing force during the drive. It is also shown that he can be more efficient by increasing the drag factor (using
higher vent setting) without increasing force. Dependence of power output on rowing style (the shape of the force curve) is
also examined. It is shown that variation of force during the drive has little effect on efficiency, but efficiency is reduced
by asymmetry of the force curve that favours the legs. 相似文献
132.
关于有氧健身操的调查与研究 总被引：9，自引：0，他引：9
通过对有氧健身操、有氧操的锻炼内容、强度及音乐的调查,认为目前参与有氧健身操不乏其人．但大多数人都进行得较盲目。建议规范健身组织以及健全健身指导员组织。 相似文献
133.
J. Avenhaus R. Gotzhein T. H?rder L. Litz K. Madlener J. Nehmer M. Richter N. Ritter D. Rombach B. Schürmann und G. Zimmermann 《Informatik - Forschung und Entwicklung》1998,13(4):227-234
Ohne Zusammenfassung 相似文献
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David Hradil Tom&#x; Grygar Janka Hradilov Petr Bezdi
ka Veronika Gr&#x;nwaldov Igor Foga&#x; Costanza Miliani 《Journal of Cultural Heritage》2007,8(4):377-386
The work is focused on identification of lead tin yellow types I and II, Naples yellow, and also on discrimination of a less common, distinct yellow pigment, the ternary Pb-Sb-Sn oxide.The knowledge about all those Pb-based yellows was in fact forgotten after introduction of modern synthetic yellows in 19th century. As late as in the last decade of the 20th century, the existence of Pb-Sb-Sn yellow and its production have been rediscovered, and only then it has been identified in colour layer of artworks.Pb-Sb-Sn yellow has recently been identified in colour layer of 17th century Italian paintings by Sandalinas and Ruiz-Moreno [C. Sandalinas, S. Ruiz-Moreno, Lead tin-antimony yellow, historical manufacture, molecular characterization and identification in seventeenth-century Italian paintings, Stud. Conserv. 49 (2003) 41–52], and here we report the finding of this pigment in Mid-European painting of the 18th and 19th centuries. Lead tin yellows, lead antimony yellow (Naples yellow), and lead antimony tin yellow were synthesized in laboratory following historical recipes, their colour was analyzed, and their structure was confirmed to provide a basis for their routine identification in microsamples of artworks by X-ray microdiffraction. Unequivocal identification of Pb-based yellows could help in authentication of traditional European paintings, because their use was temporally and also geographically specific. Combination of elemental microanalysis (X-ray fluorescence electron microanalysis) and X-ray powder microdiffraction were found very efficient in the microanalysis of colour layers of artworks with Pb-based yellows and their unequivocal identification. 相似文献
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Klaus-Peter L?hr 《Informatik - Forschung und Entwicklung》1999,14(2):61
Ohne Zusammenfassung 相似文献
140.