排序方式： 共有181条查询结果，搜索用时 15 毫秒
31.
Kelly L. Lockwood Pierre J. Gervais Donald R. Mccreary 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):231-241
Technical evaluation in the sport of figure skating is characterized by a subjective marking system. Figure skating judges are responsible for quickly and accurately discerning the quality of technical elements as well as assigning a score to the overall aesthetic appearance of a performance. Traditionally, overall placement marks are assigned for the entire performance; however, the landing of a jump is widely acknowledged as one of the most critical elements of a skater's program. Therefore, our aims were to identify the biomechanical variables that contribute to technical success in executing landings and to establish whether landings rated as biomechanically optimal are also awarded high technical merit scores by judges. Ten nationally ranked competitive figure skaters were asked to execute on‐ice, double and triple revolution jumps and to try to land the jumps void of technical faults within a calibrated space. Data were collected at 60 Hz using standard three‐dimensional videography. Data reduction was done using the APAS system (Ariel Dynamics Inc). Concurrently, videotapes were viewed and evaluated by 42 accredited judges to determine the perceived technical quality of the landing performances. Judges were asked to evaluate the landing phase of each jump against a landing criteria document. A comparative criteria model was developed to facilitate an assessment of excellence in landing performances through both empirical and subjective analyses. Results of these analyses were twofold: a biomechanical profile of on‐ice landings was obtained, and on‐ice jump landing strategies rated by empirical evaluations were in agreement with judge's perceptions of the same performances. 相似文献
32.
Allana Slater Anne Smith Leon Straker 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(1):45-56
High impact forces during gymnastic landings are thought to contribute to the high rate of injuries. Lower limb joint flexion is currently limited within gymnastic rules, yet might be an avenue for reduced force absorption. This study investigated whether lower limb flexion during three gymnastic landings was related to force. Differences between landings were also explored. Twenty-one elite women's artistic gymnasts performed three common gymnastic techniques: drop landing (DL), front and back somersaults. Ankle, knee, and hip angles, and vertical ground reaction force [(vGRF) magnitude and time to peak], were measured using three-dimensional motion analysis and force platform. The DL had significantly smaller peak vGRF, greater time to peak vGRF and larger lower limb flexion ranges than landing from either somersault. Peak vGRF and time to peak vGRF were inversely related. Peak vGRF was significantly reduced in gymnasts who landed with greater hip flexion, and time to peak was significantly increased with increasing ankle, knee, and hip flexion. Increased range of lower limb flexion should be encouraged during gymnastic landings to increase time to peak vGRF and reduce high impact force. For this purpose, judging criteria limitations on lower limb flexion should be reconsidered. 相似文献
33.
给出余指函数的定义，应用余指函数得出素数判定的一种新判别方法。此判别法在计算机上切实可行，很可能计算量是一个二次多项式级的判别方法。 相似文献
34.
胡胜 《沈阳教育学院学报》2004,6(4):136-138
主要通过文献资料法，揭示竞赛现场信息的含义及其构成因素。明确收集和处理竞赛现场信息能力培养目标，方法是以学校为中心、以市区教委和体委为基点、以专业竞赛体育组织为依托来进行的。 相似文献
35.
读者参与现场采购是图书馆实行人本服务的一项举措,有利于促进图书馆与公众和读者的交流,可以减轻采购馆员的工作压力,具有直观性、针对性和时效性较强等优点。图书馆推广读者现场采购活动要克服思想障碍,加强组织协调,激发读者兴趣,综合利用多种手段克服其不足。 相似文献
36.
运用文献资料法、问卷调查法以及数理统计法对江苏省普通高校学生的篮球裁判能力进行研究分析,并对调查结果进行统计。调查结果表明:学校重视程度不足、缺乏系统的专题培训、篮球教学课时偏少、缺少执裁实践机会以及忽视学生兴趣的培养是影响篮球裁判能力培养的主要因素。 相似文献
37.
基于4省12市实地调研中"小产权房"持有主体状况之分析,根据我国相关法律制度与访谈材料的研究结果可知,信息因素和知识因素对"小产权房"持有主体的行为选择有一定程度的影响;"小产权房"的持有行为与持有主体的家庭收入高低呈负相关性;价差因素是民众选择持有"小产权房"的主要动机;"小产权房"的持有主体对"小产权房"未来处置的期盼呈现多样化特征,且与中国当前土地制度及土地管理制度的现实和精神不完全吻合。 相似文献
38.
汪定明 《四川教育学院学报》2013,(4):118-121
英语专业学生网络自主阅读互评模式结合现有成熟网络平台,针对英语错误僵化问题,以输入假说和输出假说为理论基础,引入错误分析方式,建立了基于网络的任务型阅读小组,将英语阅读、写作、评阅、修改、纠正、错误分析等一系列活动融为一体,进行为期一年的实验。通过分析实验结果,验证该模式可以用来消除和缓解语言错误僵化问题,对英语教学具有实践性意义。 相似文献
39.
《学校用计算机》2013,30(3-4):65-78
ABSTRACT This study focused on whether Internet use improves skills for practical use of information, which is termed information literacy in Japan. Data from Japanese elementary school children (n = 702) were analyzed in a two-wave panel study in order to estimate the causal relationship between Internet use and information literacy. Structural equation modeling was the specific technique applied in a cross-lagged effect model. Results of the analysis indicated that greater use of the Internet led to higher information literacy in the whole-scale measure of practical use of information, as well as in the subskill areas of collecting, judging, and expressing information. 相似文献
40.
孙冬青 《吉林体育学院学报》2008,24(3):56-57
根据乒乓球回接旋转球技术的特点,通过对判断、移动、回接等方面的分析,讨论了乒乓球运动中回接旋转球技术的对策,解决如何提高回接旋转球的质量。 相似文献