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91.
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
92.
Researchers suggest there is an increasing apathy in the study of natural history in academic settings and in the scientific community. However, most studies of environmental knowledge do not address knowledge of local flora and fauna; they are concerned with the knowledge of environmental issues or broad ecological knowledge. Ecoliteracy established local natural history as fundamental to environmental knowledge and seeks to determine the knowledge of local environments and factors associated with that knowledge. This study investigated ecoliteracy in Mississippi, determining knowledge of local flora and fauna of undergraduate and graduate students at the largest universities. Ecoliteracy levels in Mississippi were low. Students had a rudimentary knowledge of local flora and fauna, despite coursework in natural history. Students majoring in wildlife and fisheries and biology had more advanced knowledge of local flora and fauna than non-biology majors. Students were most knowledgeable of reptiles and amphibians, and least of fish and endangered species. The number of environmental courses taken and environmental sensitivity were positively correlated with ecoliteracy, and were strong predictors of ecoliteracy. Ecoliteracy was influenced by coursework and experience with degree programs including fieldwork. Natural history knowledge was deficient at Mississippi universities. Researchers suggest reintroducing coursework focused on ecoliteracy. 相似文献
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Gabriel K. Harris Sanja Cvitkusic Amanda S. Draut Chelani S. Hathorn Amanda M. Stephens Karen E. Constanza Michael J. Leonardelli Ruth H. Watkins Lisa O. Dean Nathaniel G. Hentz 《Journal of Food Science Education》2012,11(2):23-27
Abstract: Food science laboratory courses are traditionally taught as a series of preplanned laboratories with known endpoints. In contrast, inquiry‐guided (IG) laboratories allow students to ask questions, think through problems, design experiments, then adapt and learn in response to unexpected results. This study examined the effects of converting the course, “Analytical Techniques in Food and Bioprocessing Sciences” from a traditional approach (2008 to 2010 data) to an IG approach (2011 data) by assigning teams of 2–3 students a food and a set of 5 analyses to conduct over the course of the semester. Students were required to choose and justify the use of specific methods for each analysis, as well as to develop a supply list and a budget for the semester‐long project. During the semester, students were required to post and discuss their weekly progress with the instructor, teaching assistants, and the rest of the class using an online discussion forum. At the end of the semester, students were required to present the results of their analysis in both oral and written formats. Overall course grades were significantly higher (P≤ 0.05) using IG in 2011 compared to 2010 and 2009, but not to 2008 grades. Numerical course evaluations for the instructor, overall course, and lab, as well as written course evaluations all significantly (P≤ 0.05) improved. This suggests that an IG approach may measurably improve student performance in terms of course grades and the ability to complete semester long projects. It may also increase student satisfaction with the course, as measured by numerical and written end of semester surveys. 相似文献
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The efficacy of a cognitive-based arithmetic problem-solving model (Dinnel, Glover, & Halpain, in press; Dinnel, Glover, & Ronning, 1984) was tested using 989 students with learning disabilities. Comprehensive neuropsychological test battery information was used to predict composite arithmetic test performance as a means of examining the utility of this model. Results of this study offer support for Dinnel et al.'s (Dinnel, Glover, & Halpain, in press; Dinnel, Glover, & Ronning, 1984) model in accounting for arithmetic performance under continuous visual stimulus conditions. However, these data indicate a more complex neuropsychological underpinning to arithmetic performance in both visual and aural stimulus conditions. The neuropsychological aspects of arithmetic problem solving were discussed in relationship to this cognitive-based model. 相似文献
100.
This study investigated the effects of a peer teaching procedure, combined with student letter-writing activities, on the acquisition and generalization of capitalization skills. Three students, aged 9 years, obtained instruction from peer partners that included (a) an introduction and review of capitalization rules, (b) feedback on each participant's previous capitalization work, and (c) guided and independent practice on sentences that required capitalization. All three students demonstrated acquisition of the capitalization rules after participating in the teaching sessions with one or two peer partners. In addition, there were increases in capitalization accuracy in participants' letters to peers who did not serve as teaching partners, thus demonstrating a measure of across-peer (stimulus) generalization. Mixed results were obtained on a response generalization task (sentence writing). Finally, sentencing-writing activities also showed that two of the peer partners substantially improved their use of capitalization skills as a result of teaching the target students. 相似文献