A method for personalising the blade size for competitors in flatwater kayaking

The intent of this project was to explore the feasibility of personalising the paddle blade size for individual flatwater kayakers based on their power output profiles. Twelve elite male kayakers performed on a kayak ergometer at the same intensity and resistance that they would normally experience while paddling at race pace for 500 m on the water. The kayak ergometer was instrumented so that power profiles could be determined from the instantaneous force and velocity of the representative centre point of the paddle blade. From the power profile information, the researchers calculated a personalised blade size that was expected to improve performance for those kayakers differing more than 5% from the calculated ‘ideal’ size. For the elite kayakers studied, it was recommended that seven of the paddlers should increase their blade size by approximately 5–10%. For the remaining five paddlers, the results indicated that their current blade sizes were within the expected measurement error of their predicted ideal value and should be retained. It is anticipated that this research will provide the theoretical rationale for elite kayakers to see the need to personalise their blade size based on their own muscle power profiles.     

利用情感因素优化大学英语课堂教学效果

本文从教育心理学的角度探讨了大学英语教学中情感因素的积极作用,以及如何克服消极情感,改进课堂教学策略,提高大学英语课堂教学效果.     

他砂汉语的标记被动式

他砂汉语的标记被动式有"名<,受>着+[名<,施>]+动""名<,受>+名<,施>+各+动""名<,受>着+名<,施>+各+动"等三种类型.讨论这三种标记被动式的用法及被动标志的来源.他砂汉语中由被动标记"各"和"着……各"构成的被动式均与土家语的影响有关,它们在形成过程中经历了土家语的抵抗和改造,属于汉语、土家语深度...     

游泳水槽动态阻力测量装置的研制

在介绍国内、外游泳动态阻力现状研究的基础上，从理论上重新阐述了动态阻力和推进力的定义；确立了游泳水槽动态阻力测量装置的研究方案设计和技术路线；实现了游泳项目运动学和动力学参数的同步测试，为分析、诊断、优化游泳技术动作提供了有效的科研手段。     

论儒家思想对中国传统体育竞技性的消极影响

从儒学中庸、实用主义、严格的等级制度和道德观念以及“复古”、“守陈”四个方面阐述了儒家思想对中国传统体育竞技性的消极影响,以期为中国传统体育竞技性的发展提供借鉴.     

The influence of the hand’s acceleration and the relative contribution of drag and lift forces in front crawl swimming

The aim of this study was to assess the effect of the hand’s acceleration on the propulsive forces and the relative contribution of the drag and lift on their resultant force in the separate phases of the front crawl underwater arm stroke. Ten female swimmers swam one trial of all-out 25-m front crawl. The underwater motion of each swimmer’s right hand was recorded using four camcorders and four periscope systems. Anatomical landmarks were digitised, and the propulsive forces generated by the swimmer’s hand were estimated from the kinematic data in conjunction with hydrodynamic coefficients. When the hand’s acceleration was taken into account, the magnitude of the propulsive forces was greater, with the exception of the mean drag force during the final part of the underwater arm stroke. The mean drag force was greater than the mean lift force in the middle part, while the mean lift force was greater than the mean drag force in the final part of the underwater arm stroke. Thus, swimmers should accelerate their hands from the beginning of their backward motion, press the water with large pitch angles during the middle part and sweep with small pitch angles during the final part of their underwater arm stroke.     

划水时手指张角的变化对游泳推进力影响的数值模拟

针对游泳中划水时手指应该张开与否的分歧,运用CFD数值模拟的方法,通过建立手掌和手指的简化模型,先后计算了手指分别张开不同角度及不同划水攻角时对应的阻力和阻力系数,计算结果表明手指张开角度越大其阻力和阻力系数越小。     

绘制船舶碰撞运动轨迹的数学模型探讨

根据船舶碰撞事故调查及事故报告中可获得的环境资料和船舶运动过程资料，对建立适用于绘制船舶碰撞发生前运动轨迹的数学模型作了初步探讨。     

再论武术文化的消极保护

面对武术文化近年来在保护方面存在的缺失,当前对其实施全面的消极保护意义重大。研究认为:消极保护与积极发展是武术传承过程中密不可分的两个方面;而从主观上进一步明确武术文化消极保护的重要性、人力物力上的充分保障以及消极保护方法与手段上的不断创新三个方面,是武术文化消极保护得以顺利实施的关键。     

被动运动和电刺激对失神经大鼠股骨生物力学性能影响的研究

目的:探讨被动运动和电刺激对失神经大鼠股骨生物力学性能的影响。方法:切断大鼠坐骨神经和股神经,造成失神经支配大鼠废用性骨质疏松模型,并随机将大鼠分为假手术组、对照组(NCG)、被动运动组(PMG)、电刺激组(ESG)和被动运动 电刺激组(PMESG)5组,观察各组大鼠股骨生物力学指标的变化。结果:与假手术组比较,其余各组股骨弹性模量、极限强度、结构刚度、最大载荷、能量吸收均显著性降低(P<0.05),最大应变值显著性升高(P<0.05);与对照组比较,各组弹性模量、极限强度、结构刚度、最大载荷、能量吸收均显著性升高(P<0.05),最大应变值除被动运动组仅见降低趋势外(P>0.05),其余各组均显著性降低(P<0.05)。结论:大鼠失神经支配可引起股骨生物力学性能下降,电刺激和被动运动治疗可减缓失神经大鼠股骨生物力学性能的改变。因此,被动运动和电刺激能有效预防失神经所致的废用性骨质疏松,二者联合作用效果更佳。