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1.
ABSTRACT Full three-dimensional movements and external moments in golfers’ knees and the possible involvement in injuries have not been evaluated using motion capture at high sample frequencies. This study measured joint angles and external moments around the three anatomical axes in both knees of 10 professional golfers performing golf drives whilst standing on two force plates in a motion capture laboratory. Significant differences were found in the knee joint moments between the lead and trail limbs for the peak values and throughout all stages during the swing phase. A significantly higher net abduction moment impulse was seen in the trail limb compared with the lead limb (?0.518 vs. ?0.135 Nms.kg?1), indicating greater loading over the whole swing, which could contribute to knee lateral compartment or anterior cruciate ligament injuries. A significant correlation (r = ?0.85) between clubhead speed at ball contact and maximum joint moment was found, with the largest correlations being found for joint moments at the top of the backswing event and at the end of the follow-through. Therefore, although knee moments can contribute to high clubhead speeds, the large moments and impulses suggest that they may also contribute to chronic knee injuries or exacerbate existing conditions. 相似文献
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ABSTRACT This article offers a textual analysis and semiotic reading of the Rich Kids of Tehran's (RKOT’s) Instagram page. Contributing to scholarship on Iranian youth media practices, this article interrogates how the RKOT navigate urban and rural space to engage in everyday processes of resistance against global and local systemic oppression. Grounding their visual representations on Instagram in historical and cultural context, the author questions how and when quotidian actions are transformed into political transgressions when posted on social media. This article emphasizes the RKOT's agency in shaping their brand by analyzing representations of gender performance, intertextuality, and national identity on Instagram. 相似文献
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In the IR field it is clear that the value of a system depends on the cost and benefit profiles of its users. It would seem obvious that different users would prefer different systems. In the TREC-9 filtering track, systems are evaluated by a utility measure specifying a given cost and benefit. However, in the study of decision systems it is known that, in some cases, one system may be unconditionally better than another. In this paper we employ a decision theoretic approach to find conditions under which an Information Filtering (IF) system is unconditionally superior to another for all users regardless of their cost and benefit profiles.It is well known that if two IF systems have equal precision the system with better recall will be preferred by all users. Similarly, with equal recall, better precision is universally preferred. We confirm these known results and discover an unexpected dominance relation in which a system with lower recall will be universally preferred provided its precision is sufficiently higher. 相似文献
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Stephen Court 《Higher Education Quarterly》1996,50(4):237-260
This paper reviews surveys of the use of time by academic staff between 1962 and 1994. It reports on the findings of a time diary survey in 1994 of the use of time by academic and academic-related staff at British'old'universities during working weeks in term-time and vacation. The results of the time diary survey are analysed according to respondents'sex, staff grade, type of week, age, type of work, and time when work took place. The results are compared with results of previous surveys, and trends through time are suggested. In conclusion, the paper considers the recent mass expansion of higher education, the effects of this in increasing the workload of university staff, and measures to ameliorate this situation. 相似文献
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Sports Engineering - A Monark cycle ergometer is a device globally used in physiological studies to measure the work and energy levels of exercising humans. In this paper a rope-braked cycle... 相似文献
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Stephen T. Kerr 《Publishing Research Quarterly》1992,8(4):33-43
In order to determine the potential of alternative technologies in social studies education, we must understand the goals
of such education, the capabilities of the technologies, and teachers’ and students’ responses to new technologies. The author
suggests that the new technologies can contribute to the goals of learning about the past, learning about democratic life
and institutions, and making students knowledgeable as consumers and producers of information. One major obstacle is a lack
of time and money for teachers to experiment with the technologies.
Stephen T. Kerr is professor of education in the College of Education at the University of Washington. His research focuses
on the application of new technologies in schools and other educational environments, and particularly on the ways in which
technology affects the social structure (roles and expectations, instructional patterns, organization) of those institutions.
He has done work on human-computer interaction, as well as on how new communication technologies have changed the educational
system of the former USSR. 相似文献
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