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61.
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This study compares the instrumentation and analysis techniques used when determining the power expended pedalling a rope-braked
ergometer manufactured by Monark (Sweden) during a low intensity test. Power values were generated by eight subjects. The
instrumentation consisted of load cells to measure the rope brake forces, a tachometer to measure the flywheel velocity and
instrumented pedal cranks manufactured by Schoberer Rad Messtechnik (SRM). The subjects pedalled a rope-braked ergometer at
60 rev min-1, against a resistance of 3 kg, for 5 minutes. Three different measurements of the mean power were recorded and these were
compared with the value given by Monark. The SRM cranks provided two sets of results using different software packages supplied
with the cranks. SRM standard software is used for taking measurements during training and cycle races over long time periods.
An additional piece of software is provided by SRM called Ptnew, which gives readings of torque and pedal cadence over periods
up to 30 seconds. Using the values supplied by Monark each subject generated 180 W of power. The mean power for the eight
subjects, measured using the SRM cranks, was 170.36 W (SD 4.11) using the alternative SRM software (Ptnew) over a 30 second
period and 173.68 W (SD 2.21) using the standard SRM software. From the direct measurement of the brake forces and flywheel
velocity the mean power across the eight subjects was 148.90 W (SD 5.89). The SRM cranks measure the input power, whereas
the direct measurement system measures the power output excluding mechanical losses. These values give a figure for the mechanical
efficiency for the roped-braked ergometer of 88%. It was found that Monark overestimates the power generated by the subjects
when compared with both the SRM systems and the direct measurement instrumentation. 相似文献
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64.
This second part of a two-part paper describes how the University of California, San Francisco (UCSF) Library implemented a bibliographic control system for a medical illustrations collection. Discussed are the staffing of the project, the design of formats and computer programs, further design changes, the input process, quality evaluation of the illustrations, and production and distribution of the control products (printed indexes and microfiche replicas). The report ends with a note on the applicability of the UCSF system to other libraries, and some benefits of the project. 相似文献
65.
Gordon E Finley 《Int J Intercult Relat》1979,3(1):5-13
Although the topic of research collaboration receives infrequent comment, a well functioning collaborative process is crucial to the substantive success of intercultural research enterprises. The present report addresses this topic and focuses on two major sets of collaborative issues, the personal/ personnel and the structural/organizational. The issues are organized around the phases of the project at which they optimally should be considered and resolved. 相似文献
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