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931.
932.
C. Musili 《Resonance》1997,2(1):44-52
An attempt is made here to provide a mathematical model which can explain an intriguing talent of Nakula. On the way, some simple and interesting properties of the real number system and related material are discussed. 相似文献
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Measurement of ground reaction force (GRF) in running provides a direct indication of the loads to which the body is subjected
at each foot-ground contact, and can provide an objective explanation for performance outcomes. Traditionally, the collection
of three orthogonal component GRF data in running requires an athlete to complete a series of return loops along a laboratory
based runway, within which a force platform is embedded, in order to collect data from a discrete footfall. The major disadvantages
associated with this GRF data collection methodology include the inability to assess multiple consecutive foot contacts and
the fact that measurements are typically confined to the laboratory. The objective of this research was to investigate the
potential for wearable instrumentation to be employed, in conjunction with artificial neural network (ANN) and multiple linear
regression (MLR) models, for the estimation of GRF in middle distance running. A modular wearable data acquisition system
was developed to acquire in-shoe force (ISF) data. Matched data sets from wearable instrumentation (source data) and force
plate (target data) records were collected from elite middle-distance runners under controlled laboratory conditions for the
purposes of ANN and MLR model development (MD) and model validation (MV).
In terms of statistical measures of prediction accuracy the MLR model was found to provide a superior level of accuracy for
the prediction of the vertical and medio-lateral components of GRF and alternatively, the ANN model provided the most accurate
predictions of the anterior-posterior component of GRF. The prediction accuracy of each component of GRF was found to be governed
by the inherent signal variability, in which case the vertical and anterior-posterior components were more reliable and subsequently
predicted significantly more accurately than the medio-lateral component.
The emerging capability for obtaining continuous GRF records from wearable instrumentation has the potential to permit unprecedented
quantification of training stress and competition demands in running. 相似文献
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目前关于体育教学实习成绩的评定,各院校做法不一,还没有定论。但就目前各校的评估量表看,普遍较复杂,计算量大,指标多,内容不具体,因而不适用。而且对体育教学大都只重视一次公开课或检查课,对平时课堂教学不大重视。因此,制定出客观、全面、简便易行的评估指标体系就具有很重要的意义。 相似文献
939.
Judit Bar-Ilan Bluma C. Peritz Yecheskel Wolman 《The Journal of Academic Librarianship》2003,29(6):67-361
The results of an extensive survey of the senior academic staff of the Israeli universities on their use of electronic journals and databases are presented. The major findings are that the use of electronic sources is already widespread among the respondents and more than 50% found the electronic services indispensable. Disparities were found between the usage patterns in the different disciplines. 相似文献
940.
This study aimed to investigate the comparative value of experimenting with physical manipulatives (PM) in a sequential combination with virtual manipulatives (VM), with the use of PM preceding the use of VM, and of experimenting with PM alone, with respect to changes in students' conceptual understanding in the domain of heat and temperature. A pre–post‐comparison study design was used which involved 62 undergraduate students that attended an introductory course in physics. The participants were randomly assigned to one experimental and one control group. Both groups used the same inquiry‐oriented curriculum materials. Participants in the control group used PM to conduct the experiments, whereas, participants in the experimental group used first PM and then VM. VM differed from PM in that it could provide the possibility of faster manipulation, whereas, it retained any other features and interactions of the study's subject domain identical to the PM condition. Conceptual tests were administered to assess students' understanding before, during, and after the study's treatments. Results indicated that experimenting with the combination of PM and VM enhanced students' conceptual understanding more than experimenting with PM alone. The use of VM was identified as the cause of this differentiation. © 2008 Wiley Periodicals, Inc. J Res Sci Teach 45: 1021–1035, 2008 相似文献