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本文以4200t/h装船机伸缩机构中常用的销齿条传动为例分析,利用ANSYS结构有限元分析软件,具体分析了销齿条传动过程中销轴的弯曲应力分布图,为销齿条传动中销轴的设计和加工提供了相关参考数据. 相似文献
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齿轮损坏是机械传动装置中容易出现的问题,利用渐开线直齿圆柱齿轮参数测定技术,解决设备维修中齿轮损坏的实际问题,说明继承成熟技术本身也是一种创新. 相似文献
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本文提出了一种新型的上肢康复机构,将3-RRS机构应用在上肢康复机构中。首先对3-RRS机构进行位置正解分析,然后根据算例,应用matlab软件得出在一定的驱动条件下,动平台中心位置运动的位移、速度和加速度曲线。并分析该机构的性能,可知此机构适用于人体上肢康复运动。 相似文献
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十三、“新航线号”扑翼机
飞机的问世实现了人类飞行的梦想,但有一种飞行模式,人类至令也没有真正将其征服,那就是扑冀飞行。除去材料方面的难点,实现扑翼飞行还有很多困难,如传动,平衡控制、以及如何实现既能扑冀又能向前飞行等。 相似文献
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近年来,德国的很多体育专家和政治家认为,由奥委会和体联两套机构管理体育的方式效率低、花费大,应该建立一个统一的主管机构。目前德国奥委会和德国体联正在有计划地商议合并问题。2005年6月2 8日,德国体联和德国奥委会共同成立的组织机构委员会将两家机构合并的草案公之于众,提请讨论。新机构的名字拟为德国奥林匹克体育联盟(DOSB)。2005年9月23日,德国各州体联就此召开特别会议,并发表声明,支持合并,期望提升大众体育在新机构中的地位。 相似文献
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This study examined the effect of carbohydrate ingestion on metabolic and performance-related responses during and after a simulated 1h cycling time trial. Eight trained male cyclists (VO 2 peak = 66.5ml kg -1 min -1 ) rode their own bicycles mounted on a windload simulator to imitate real riding conditions. At a self-selected maximal pace, the cyclists performed two 1h rides (separated by 7 days) and were fed either an 8% carbohydrate or placebo solution. The beverages were administered 25 min before (4.5ml kg -1 ) and at the end (4.5ml kg -1 ) of the ride. With carbohydrate feeding, plasma glucose tended (P = 0.21) to rise before the time trial. Compared with rest, the plasma glucose concentration decreased significantly (P < 0.05) at the end of both rides, with no statistically significant difference being observed between treatments. Thereafter, plasma glucose increased significantly (P < 0.05) at 15 and 30 min into recovery, and was significantly higher at 30 min during the carbohydrate trial compared with the placebo trial. No significant changes in plasma free fatty acids were observed during the ride. However, a significant increase (P < 0.05) in free fatty acids was found at 15 and 30 min into recovery, with no difference between trials. Mean power output was significantly (P < 0.05) greater during the carbohydrate compared with the placebo trial (mean - S.E.: 277-3 and 269-3W, respectively). The greater distance covered in the carbohydrate compared with the placebo trial (41.5-1.06 and 41.0–1.06km, respectively; P < 0.05) was equivalent to a 44s improvement. We conclude that pre-exercise carbohydrate ingestion significantly increases endurance performance in trained cyclists during a 1h simulated time trial. Although the mechanism for this enhancement in performance with carbohydrate ingestion cannot be surmised from the present results, it could be related to a higher rate of carbohydrate oxidation, or to favourable effects of carbohydrate ingestion on the central component of fatigue. 相似文献
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Roy J. Shephard 《Journal of sports sciences》2013,31(7):603-620
The biology and medicine of rowing are briefly reviewed. Effort in a 2000 -m race is about 70% aerobic. Because the boat (and in some instances a cox) must be propelled, successful competitors are very tall, with a large lean mass and aerobic power. Large hearts may lead to erroneous diagnoses of a cardiomyopathy. Large respiratory minute volumes must be developed by chest muscles that are also involved in rowing. The vital capacity is typically large, and breathing becomes entrained. Expiration cannot be slowed relative to inspiration (as normally occurs at high rates of ventilation) and the limiting flow velocity may be reached, with the potential for airway collapse. Performance is strongly related to the power output at the ‘anaerobic threshold’, and lactate measures provide a guide to an appropriate intensity of endurance training. Peak blood lactate levels are higher in males (commonly 11–19 mmol·l -1 and occasionally as high as 25 mmol·l -1) than in females (9–11 mmol·l -1), probably because males have a greater muscle mass in relation to blood volume. The skeletal muscles are predominantly slow twitch in type, developing an unusual force and power at low contraction velocities. Many rowers have a suboptimal diet, eating excessive amounts of fat. Lightweight rowers also have problems of weight cycling. Aerobic power and muscle endurance often change by 10% over the season, but such fluctuations can be largely avoided by a well-designed winter training programme. Injuries include back and knee problems, tenosynovitis of the wrist and, since the introduction of large blades, fractures of the costae. 相似文献
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重新认识体育的社会关联 总被引:3,自引:1,他引:2
体育与政治之间存在一个悖论,体育的发展与经济实力之间没有直线相关,体育与教育部分重叠,体育与宗教最为近缘,体育可借用科学手段,体育的艺术禀性日益明显,体育与养生反映着两种人生观。 相似文献
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本文在专家访谈、问卷调查、数理统计和文献资料分析的基础上,探析了上海社区体育竞赛参与者的特点、参与者对社区体育赛事运作管理的看法等问题。在此基础上从引进社区体育赛事的志愿者、整合社区体育赛事的各种资源、开发社区体育竞赛的无形资产、组建非营利性的专业团队、规范社区体育赛事的服务管理等方面提出了进一步满足上海社区居民日益增长的体育竞赛参赛需求的对策与措施。 相似文献
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对全面把握游泳训练环节的探讨 总被引:4,自引:0,他引:4
从系统观点出发,结合训练实践,对全面把握游泳训练环节进行探讨。认为应强化非智力因素在运动员多年训练中的作用,在育材全过程中不断选材,从整体上把握动态训练的全过程,把培养高水平运动员的整个过程置于一个严格的科学控制之下。 相似文献
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结合欧洲足球技战术的发展特点,就鲁能泰山足球队的体能训练、技术训练、防守阵型、进攻方式、定位球、职业态度、球星培养等诸方面所存在的不足进行了分析,提出相应的改进意见。 相似文献
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朱新新 《体育科技文献通报》2010,18(3):52-53,57
本文运用文献资料法,逻辑分析法,在遵循逻辑学、哲学、心理学原理的前提下,对竞技健美操技术的概念进行了界定,对竞技健美操技术进行了分类研究,在此基础上分析了竞技健美操技术的结构,为系统、科学的组织竞技健美操的教学和训练提供理论上的参考,为促进竞技健美操理论体系的完善和协调发展做出一定的贡献。 相似文献
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本文运用文献资料法、历史法、因素分析等方法,从体育考古学的角度对古滇国主要墓葬群出土文物进行深入研究.研究表明:古滇文化已具备体育文化构建因子,滇国在重大节日举行的斗牛、竞渡、磨秋、剽牛祭祀等民俗活动中已彰显出体育的特色,是古滇民族主要的民俗体育活动形式.古滇人民观念不羁、思想无垠,演绎了独具特色的古滇民俗体育文化,是我们中华民族灿烂辉煌的体育文化中的一支奇葩. 相似文献
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进入21世纪以来,我国经济进入经济转型期,内需拉动型经济成为我国经济发展的新方向。人口数量的激增,老龄化程度的加重成为了我国经济发展的又一障碍。重视老年人蕴藏的巨大社会价值,发展老年体育产业将成为我国增强内需的一条新思路。 相似文献