Human kinematics and event control: on-line movement registration as a means for experimental manipulation     

Oudejans RR  Coolen BH 《Journal of sports sciences》2003,21(7):567-576

In human movement and sports science, manipulations of perception and action are common and often comprise the control of events, such as opening or closing liquid crystal goggles. Most of these events are externally controlled, independent of the actions of the participants. Less common, although sometimes desirable, are event manipulations that are dependent on the unconstrained movements of participants. As an example, we describe a method we used previously to manipulate vision of basketball jump shooters on the basis of on-line registration of their own movements. The shooters wore liquid crystal goggles that opened or shut as a function of specific kinematic features of these movements. The novel aspect of this method is that the criteria for detecting movement patterns and performing the appropriate manipulations are adjustable to the specific sport context and the complexity and variations of the unconstrained movements. The method was implemented as a finite state machine: a computer system that can be used for pattern recognition. We discuss this method, how it works and the potential it has for studying perceptual-motor skills in sport. Furthermore, the results of the basketball experiment are briefly summarized and complemented with new analyses.  相似文献   

Learning from the experts: practice activities of expert decision makers in sport   总被引：3，自引：0，他引：3  

Baker J  Côté J  Abernethy B 《Research quarterly for exercise and sport》2003,74(3):342-347

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论图书馆工作应以读者为本   总被引：17，自引：1，他引：16  

郭大仁 《四川图书馆学报》2003,(1):39-41

读者的要求是图书馆发展的动力,随着现代文明的不断发展,“以读者为本”的办馆思想,将逐步融于图书馆的各项工作之中,成为引领21世纪图书馆发展的新理念。  相似文献   

开放性课程资源在五年制学前教育专业地理教学中的应用研究     

杨达 《教育与教学研究》2011,(9):72-75

新的地理课程标准强调学习对生活有用的、对终身发展有用的地理。非常重视校外地理课程资源的开发利用,形成学校与社会、家庭密切联系,教育资源共享的开放性课程。开放性是指进行课堂教学时所摄取的资源不仅仅局限于课堂上和书本里,要挖掘蕴藏在学校、家庭、社区、社会生活中更为丰富的课程资源。五年制学前教育专业学生的学习能力不是很强,只有充分利用开放性课程资源进行教学,才能很好地提高课堂教学质量,改善教学方法,激发学生学习的兴趣,培养学生的综合能力,完成课标要求。  相似文献   

Screening of Xylanolytic Aspergillus fumigatus for Prebiotic Xylooligosaccharide Production Using Bagasse     

Ana Flavia Azevedo Carvalho  Pedro de Oliva Neto  Paula Zaghetto de Almeida  Juliana Bueno da Silva  Bruna Escaramboni  Glaucia Maria Pastore 《Food Technology and Biotechnology》2015,53(4):428-435

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Disrupting the wall accumulation of human sperm cells by artificial corrugation     

H. A. Guidobaldi  Y. Jeyaram  C. A. Condat  M. Oviedo  I. Berdakin  V. V. Moshchalkov  L. C. Giojalas  A. V. Silhanek  V. I. Marconi 《Biomicrofluidics》2015,9(2)

Many self-propelled microorganisms are attracted to surfaces. This makes their dynamics in restricted geometries very different from that observed in the bulk. Swimming along walls is beneficial for directing and sorting cells, but may be detrimental if homogeneous populations are desired, such as in counting microchambers. In this work, we characterize the motion of human sperm cells ∼60 μm long, strongly confined to ∼25 μm shallow chambers. We investigate the nature of the cell trajectories between the confining surfaces and their accumulation near the borders. Observed cell trajectories are composed of a succession of quasi-circular and quasi-linear segments. This suggests that the cells follow a path of intermittent trappings near the top and bottom surfaces separated by stretches of quasi-free motion in between the two surfaces, as confirmed by depth resolved confocal microscopy studies. We show that the introduction of artificial petal-shaped corrugation in the lateral boundaries removes the tendency of cells to accumulate near the borders, an effect which we hypothesize may be valuable for microfluidic applications in biomedicine.  相似文献   

Kinematic,kinetic and EMG analysis of four front crawl flip turn techniques     

Suzana Matheus Pereira  Caroline Ruschel  Marcel Hubert  Leandro Machado  Helio Roesler  Ricardo Jorge Fernandes 《Journal of sports sciences》2015,33(19):2006-2015

This study aimed to analyse the kinematic, kinetic and electromyographic characteristics of four front crawl flip turn technique variants. The variants distinguished from each other by differences in body position (i.e. dorsal, lateral, ventral) during rolling, wall support, pushing and gliding phases. Seventeen highly trained swimmers (17.9 ± 3.2 years old) participated in interventional sessions and performed three trials of each variant, being monitored with a 3-D video system, a force platform and an electromyography (EMG) system. Studied variables: rolling time and distance, wall support time, push-off time, peak force and horizontal impulse at wall support and push-off, centre of mass horizontal velocity at the end of the push-off, gliding time, centre of mass depth, distance, average and final velocity during gliding, total turn time and electrical activity of Gastrocnemius Medialis, Tibialis Anterior, Biceps Femoris and Vastus Lateralis muscles. Depending on the variant, total turn time ranged from 2.37 ± 0.32 to 2.43 ± 0.33 s, push-off force from 1.86 ± 0.33 to 1.92 ± 0.26 BW and centre of mass velocity during gliding from 1.78 ± 0.21 to 1.94 ± 0.22 m · s^?1. The variants were not distinguishable in terms of kinematical, kinetic and EMG parameters during the rolling, wall support, pushing and gliding phases.  相似文献   

泉州师范学院大学生体质健康状况及变化趋势的研究     

张达 《湖北体育科技》2015,(7):587-589

运用文献资料、测试、调查和数理统计等方法,对2011-2013年泉州师范学院在校大学生体质健康标准测试数据进行统计分析,总结研究区间内该校大学生体质健康状况及其变化趋势,为学校全面掌握学生的体质健康状况以及准确把握体育工作重点和努力方向提供科学依据,同时针对暴露出的体质健康问题提出相应改进建议。  相似文献   

钢筋增强超高韧性水泥基复合材料梁的剪切性能试验研究     

Li-jun HOU  Zhi-yong LUAN  Da CHEN  Shi-lang XU 《浙江大学学报(A卷英文版)》2015,(4)

目的：揭示不同剪跨比和配箍率的钢筋增强超高韧性水泥基复合材料（RUHTCC）梁的抗剪性能,为超高韧性水泥基复合材料（UHTCC）用于结构关键抗剪部位提供参考。方法：基于抗剪试验结果,阐明剪跨比和配箍率对RUHTCC梁抗剪性能的影响,明确UHTCC与箍筋之间的复合抗剪效应,揭示 RUHTCC 梁的抗剪机理。方法：以剪跨比和配箍率为变量参数,通过 RUHTCC梁在跨中集中荷载作用下的弯曲试验,研究RUHTCC 梁的剪切裂缝形态、荷载-挠度行为、破坏模式、开裂剪切强度和极限剪切强度等抗剪性能,并结合试验结果,分析 RUHTCC 梁的剪力传递机理。结论：1. RUHTCC梁呈现出优良的剪切抗力以及稳态的斜裂缝扩展过程和多缝剪切开裂行为。2.配置少量的箍筋可将典型的剪切破坏转变为较为延性的弯剪破坏甚至弯曲破坏。然而,箍筋的配置并未显著提高 RUHTCC 梁的抗剪能力,同时耦合UHTCC与箍筋也没有表现出协同抗剪效应。3.拉杆-拱模型和桁架-拱模型可用以描述RUHTCC短梁和细长梁的抗剪机理。  相似文献   

学前教育中羌文化传承的“生态语境”与“叙事体验”探究     

来嫔  杨达 《康定民族师范高等专科学校学报》2015,24(2)

羌文化是多元文化中的重要一支,却面临着羌语濒危,文化主体、文化传承“生态语境”缺失,文化传承行为严重失衡等现实困境.学前儿童是未来文化主体,教育是人类文化得以传承的主要途径,学前教育是实施民族文化传承教育的关键期和重要期,学前教育中羌文化传承“语境”损毁而导致羌文化传承教育弱化.因此,塑造学前教育羌文化传承的“生态语境”,突围羌文化传承困境,实施学前儿童羌文化传承“叙事体验”教育,是学前教育羌文化传承的有效建设和重要驱动.  相似文献