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31.
A rationale and geometric parameters for optimal basketball shooting are provided. The premise is that shots requiring the
least energy are the easiest to control and thus have the greatest probability of success. The kinematics of the ball movement
are modelled and simulated for the free throw, for the direct shot, and for the bank shot off the backboard (the ‘layup’).
For the layup, the analysis includes the effects of friction, ball inertia, ball spin and impact restitution. The results
provide a means for shot planning and for coaching to improve shooting technique. The advantage of the layup for close-in
shooting is demonstrated. Results of numerical parameter studies are also presented, demonstrating the ranges of allowable
shooting error for the various shots, and thus also identifying the shots with highest probability of success. 相似文献
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33.
Irineu Loturco Lucas Adriano Pereira Cesar Cavinato Cal Abad Facundo Tabares José Eduardo Moraes Ronaldo Kobal 《Journal of sports sciences》2017,35(8):734-741
This study aimed at testing whether there are mean propulsive velocities (MPVs) capable of maximising the mean propulsive power (MPP) during the execution of bench press (BP), bench throw (BT), half squat (HS) and jump squat (JS). Additionally, we assessed the differences in MPP/MPV between ballistic and traditional exercises. Seventeen male rugby sevens players performed MPP tests in BP, BT, HS and JS and maximum isometric force (MIF) tests in HS and BP. The JS presented higher MPP (977.4 ± 156.2 W) than the HS (897.9 ± 157.7 W) (P < 0.05); the BP (743.4 ± 100.1 W) presented higher MPP than the BT (697.8 ± 70.4 W) (P < 0.05). Ballistic exercises presented higher optimum MPV (JS = 1.02 ± 0.07 m·s?1; BT = 1.67 ± 0.15 m·s?1) than traditional exercises (HS = 0.93 ± 0.08 m·s?1; BP = 1.40 ± 0.13 m·s?1) (P < 0.05). The optimum MPP in the JS, BT, HS and BP occurred at 28.2 ± 5.79, 23.3 ± 4.24, 32.4 ± 9.46 and 27.7 ± 5.33% of the MIF, respectively. The coefficient of variation (CV) of MPV at optimum MPP ranged from 7.4% to 9.7%, while the CV of %MIF ranged from 18.2% to 29.2%. The MPV is a more precise indicator of the optimum loads than the percentages of MIF due to its low inter-subject variability as expressed by CV. Therefore, MPV can be used to determine the optimum power load in the four investigated exercises. 相似文献
34.
The concept of industrial clustering has been studied in-depth by policy makers and researchers from many fields, mainly due to the competitive advantages it may bring to regional economies. Companies often take part in collaborative initiatives with local partners while also taking advantage of knowledge spillovers to benefit from locating in a cluster. Thus, Knowledge Management (KM) and Performance Management (PM) have become relevant topics for policy makers and cluster associations when undertaking collaborative initiatives. Taking this into account, this paper aims to explore the interplay between both topics using a case study conducted in a collaborative network formed within a cluster. The results show that KM should be acknowledged as a formal area of cluster management so that PM practices can support knowledge-oriented initiatives and therefore make better use of the new knowledge created. Furthermore, tacit and explicit knowledge resulting from PM practices needs to be stored and disseminated throughout the cluster as a way of improving managerial practices and regional strategic direction. 相似文献
35.
We designed and used a series of activities （named activities to teaching electric field （ATEF）） based on the Physics by Inquiry （PBI） strategy to teaching the electric field concept with university students. We used a concentration factor tool to assess the effectiveness of those activities used during three weeks of instruction. Results indicate that students who had traditional teaching obtained a very tiny gain （less than 1%）; concentration factors indicate that most of their responses fall into a random area, which is not favorable. On the other hand, the experimental group using our activities had greater gains （〉 10%） than the control group. Concentration factors showed that after instruction, students＇ mental models changed toward a favorable pattern about comprehension of electric field concept and Coulomb＇s law. A hypothesis test of two samples indicated that there is a significant difference between both traditional teaching and ATEF based on PBI. 相似文献
36.
Measuring the continuum of literacy skills among adults: educational testing and the LAMP experience
Cesar Guadalupe Manuel Cardoso 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2011,57(1-2):199-217
The field of educational testing has become increasingly important for providing different stakeholders and decision-makers with information. This paper discusses basic standards for methodological approaches used in measuring literacy skills among adults. The authors address the increasing interest in skills measurement, the discourses on how this should be done with scientific integrity and UNESCO??s experience regarding the Literacy Assessment and Monitoring Programme (LAMP). The increase in interest is due to the evolving notion of literacy as a continuum. Its recognition in surveys and data collection is ensured in the first commitment in section?11 of the Bel??m Framework for Action. The discourse on how measurements should be carried out concerns the need to find valid parsimonious approaches, also their relevance in different institutional, cultural and linguistic contexts as well as issues of ownership and sustainability. Finally, UNESCO??s experience with LAMP shows how important addressing these different issues is in order to equip countries with an approach that is fit for purpose. 相似文献
37.
Cesar R Torres 《国际体育史杂志》2013,30(3):344-364
For more than a century Baron Pierre de Coubertin was believed to be a self-inspired Olympic forebear. That idea has recently been challenged, most notably by historian David Young. According to Young, de Coubertin took the idea of international Olympic Games in modern times from W. P. Brookes. Young bases his case on new evidence found in the Brookes’s archives. In this article I present another piece of evidence helping to corroborate Brookes’s influence on de Coubertin’s work. Such evidence comes from the personal report of Alejo Peyret, a member of the Argentine delegation to the 1889 Paris Universal Exposition in which de Coubertin hosted the International Congress for the Propagation of Physical Exercise. In his report, Peyret provided a detailed account of all of the activities of the congress and commented on the state of physical education in France. By analyzing Peyret’s report, this article concludes that in mid-1889 de Coubertin was not concerned with reviving the Olympic Games. His focus was on improving France’s poor physical training system. This article also discusses the impact that the Argentine participation in the congress had on its incipient physical education and sporting movements. 相似文献
38.
Ricardo Dantas de Lucas Fabrizio Caputo Kristopher Mendes de Souza AndrÉ Roberto Sigwalt Karina Ghisoni Paulo Cesar Lock Silveira 《Journal of sports sciences》2013,31(1):22-27
Whole-body bone mineral density and bone mineral mass in young adult rugby union players. 相似文献
39.
In 1972 I attended the Pre-Olympic Scientific Congress in Munich. For the first time science and sport were brought together in connection with the Olympic Games. The organizers presented a book Sport in Blickpunkt der Wissenschaften (Sport from a Scientific Point of View) that summarized history and state of the art of the main sport scientific approaches (41). The German philosopher Hans Lenk gave a presentation of a broad array of past and present interpretations of sport from a philosophic viewpoint (49). The congress in Munch and Hans Lenk's presentation of sport as a suitable philosophic topic became decisive for my own lifelong interest in philosophy of sport. Soon after the Munich conference some American philosophers convened to launch the Philosophic Society for the Study of Sport. In 1973 the first issue of Journal of Philosophy of Sport was published (35). In several ways 1972 was a turning point for philosophy of sport as a serious academic discipline and for my own interest in sport philosophy. From here sport philosophy found its way to Norway and through this and along several other roads to other Nordic countries. 相似文献