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Many scientists and coaches are interested in mechanical power produced during cycling, and use Schoberer Rad Me\technik (SRM)
bicycle power cranks to obtain this data. However, it has been expensive and difficult to calibrate SRM cranks, causing much
of the collected data to be unreliable. We present a static method, derived from first principles, for obtaining a calibration
factor for SRM cranks.
A known mass and lever arm (chainring of a known diameter) are used to apply a known torque load to the instrument in four
positions, and the output frequencies are used to calculate the calibration factor in Hz/Nm. The reproducibility of this method
is ±0.01 Hz/Nm, which is acceptable for the application of the instrument, which is measurement of mechanical power application
by cyclists at the crank.
The method is reliable, inexpensive, and easy to set up, and will allow higher confidence in data collected using SRM power
cranks. We recommend calibration of the power meter once every six months because of the measured drift of the calibration
factor over time. 相似文献
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We examined the demographic distribution of 102 subjects with attention deficits in the Wechsler Intelligence Scale for Children-Revised (WISC-R) (Wechsler, 1974) standardization sample. Neither age nor occupational status was significant; males were overrepresented (3:1); and the West was overrepresented by 50%, largely due to the relatively high proportion of females in the West who appeared within the attention deficit sample (41% in West vs. 19% in the rest of the nation). Replication is encouraged. 相似文献
997.
S. S. Hanna 《Publishing Research Quarterly》1990,6(2):37-43
What happens when an author undertakes a supplementary marketing campaign to university librarians? S. S. Hanna, the author of a comic account of finding a publisher, added to the efforts of the Iowa State University Press some communications of his own. The details of his campaign, and some of its results, are offered. 相似文献
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