排序方式： 共有61条查询结果，搜索用时 15 毫秒
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本研究利用Cybex6000肌肉力量等动测试评定系统,对10名优秀男子赛艇运动员的躯干肌群的力量进行向心等动测试,测试速度分别为60°/s、120°/s、180°/s、240°/s.测试的结果表明优秀赛艇运动员的躯干屈伸肌群的相对峰力矩、相对功均随着测试速度的增加而逐渐减少,屈伸肌群的相对功率随着测试速度的增加而增加,并且屈肌在240°/s达到最大值,而伸肌在180°/s左右已达到最大值. 相似文献
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Leo Ng Angus Burnett Amity Campbell Peter O'Sullivan 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):255-259
The aim of the study was to determine the accuracy and variability of an electromagnetic device in measuring spinal kinematics on a traditional and replica rowing ergometer. Kinematic data collected from the 3-Space FastrakTM system using a Standard Concept II ergometer were compared with a replica ergometer that was in part, composed of non-ferrous materials (modified ergometer). The Fastrak's sensors were fixed to a wooden “spine” with known angles (as measured by an inclinometer). The mean inclinometer angle from four sensors (1 ± 0.2°) was significantly different than the mean angle recorded on the standard ergometer ( ? 5.4 ± 3.4°) (p = 0.007) whilst the angles recorded on the modified ergometer (1.4 ± 0.8°) were statistically equivalent to the inclinometer recordings (p = 0.660). These results indicate that the presence of ferrous material in a standard ergometer reduced the accuracy and increased the variability of data collected with the electromagnetic device. However, information collected on largely non-ferrous ergometers can provide coaches, biomechanists and clinicians with a quick and effective way to measure trunk kinematics during ergometer rowing. 相似文献
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Christopher Joyce Angus Burnett Jodie Cochrane Kevin Ball 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):108-120
The aims of this study were (i) to determine whether significant three-dimensional (3D) trunk kinematic differences existed between a driver and a five-iron during a golf swing; and (ii) to determine the anthropometric, physiological, and trunk kinematic variables associated with clubhead speed. Trunk range of motion and golf swing kinematic data were collected from 15 low-handicap male golfers (handicap = 2.5 ± 1.9). Data were collected using a 10-camera motion capture system operating at 250 Hz. Data on clubhead speed and ball velocity were collected using a real-time launch monitor. Paired t-tests revealed nine significant (p ≤ 0.0019) between-club differences for golf swing kinematics, namely trunk and lower trunk flexion/extension and lower trunk axial rotation. Multiple regression analyses explained 33.7–66.7% of the variance in clubhead speed for the driver and five-iron, respectively, with both trunk and lower trunk variables showing associations with clubhead speed. Future studies should consider the role of the upper limbs and modifiable features of the golf club in developing clubhead speed for the driver in particular. 相似文献
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针对场技术课程教师"难教"、学生"难学"的状况,将相关课程组成以"电磁场理论"为基础的射频方向课程群,找出主干脉络;并针对课程实践性强的特点,开发了与课程群课程相关的实践项目。在教学过程中对教学方法、教学手段、实践教学进行了相应改革。结果表明,这些方法的实施减轻了学生对场技术课程的畏惧心理,激发了学习兴趣,使他们的实践能力和创新能力得以提高。 相似文献
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目的:描述艺术体操运动员在日常状况下和完成专项动作时脊柱异常的表现及左右对称性,探讨与之相关的因素。方法:以9名艺术体操运动员为研究对象,进行站立位脊柱X光片拍摄,获得脊柱额状面和矢状面的弯曲方向和角度;使用三维摄像方法定量评价运动员完成后搬腿动作和侧搬腿动作时的脊柱活动幅度;运用后伸肌群和双侧屈肌群测试系统对运动员的坐姿躯干后伸和双侧侧屈等长收缩力量进行测试。比较躯干活动幅度和躯干肌肉力量的左右对称性,比较不同脊柱侧凸方向间躯干活动差异。检验脊柱弯曲角度与躯干活动特征的相关性。结果:后搬左侧腿时的活动幅度显著小于后搬右侧腿(P<0.01),对应躯干向左扭转的幅度显著大于向右扭转幅度(P<0.05)。侧搬腿时躯干活动幅度越大对应的躯干扭转角度越大。胸曲角度与右侧搬腿活动幅度角存在正相关(P<0.05),与右侧搬腿躯干扭转角之间为显著负相关(P<0.05),腰曲角度与左侧搬腿活动幅度角之间存在显著正相关(P<0.05),与右侧搬腿躯干扭转角之间存在显著负相关(P<0.05)。肌肉力量方面,胸曲角度越大,3个位置躯干后伸力矩峰值越小。侧屈力量上,运动员绝大多数角度下的右屈力量显著大于左屈力量。胸曲角度、腰°曲角度分°别与不同躯干侧屈角度下右屈力矩峰值存在显著负相关。腰曲角度与左屈0、15°、30和右屈15°位置的躯干左屈力矩峰值存在显著负相关。结论:艺术体操运动员躯干两侧活动度和肌肉力量存在不对称,后伸幅度左侧大于右侧,侧屈肌力右侧大于左侧;但这种不对称与脊柱额状面上异常弯曲无明显关系;集中于躯干右侧和躯干后伸动作的训练,可能是导致胸曲变直的原因。 相似文献
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一般的 2层交换机与 3层交换机之间的互联可通过桥接、中继、单臂路由及VLAN等方式 ,这基于一个前提就是它们都支持同一的标准 .IEEE 80 2 .1Q就是局域网通过VLAN互联的标准 . 相似文献
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陈彦祥 《包头职业技术学院学报》2008,9(2)
依据JJG133-2005<汽车油罐车容量>检定规程和工作经验,参照国家计量技术规范JJF1059-1999<测量不确定度的评定与表示>,对汽车油罐车容量测量结果不确定度进行了评定. 相似文献