武汉亚锦赛中国男篮获胜核心因素研究——以进攻和防守技术为分析对象

第26届亚锦赛男篮比赛已经落下帷幕,中国队、约旦队、韩国队分获冠、亚、季军。我国男篮在取得成绩的同时,也存在着诸多问题。运用文献资料法、观察法、数理统计法对武汉亚锦赛男篮的各项技术进行研究,分析我国男篮的优势与劣势,为男篮备战2012年伦敦奥运会提供有价值的参考。     

Ground reaction force characteristics of Tai Chi push hand

Abstract

Push Hand is an advanced training technique for the Yang-style old frame 108 forms Tai Chi Chuan. It is performed by two practitioners. To clarify how people use forces during Push Hand training, it is important to review the ground reaction force (GRF). Here, we quantify the characteristics of the GRF during Push Hand training. Kinematic data and GRF data from 10 Tai Chi Chuan practitioners (29.9 ± 7.87 years) were synchronously recorded using a three-dimensional motion analysis system (200 frames · s^?1) and three-dimensional force plates (1000 Hz). The resultant GRF for both feet for the 0%, 50% and 100% phases of attack and defence were compared to body weight using a paired-samples t-test. The differences in the resultant GRF between the 0%, 50% and 100% phases of attack and defence were tested by one-way repeated-measures ANOVA. The significance level was set to 0.05. The total resultant GRF was almost equal to the participant’s body weight in push hand. This result was consistent throughout the entire push hand process. Our results revealed that the GRF was comparable to the body weight, implying that practitioners do not push or resist their opponents during the push hand process.     

Dynamics of the martial arts high front kick

Fast unloaded movements (i.e. striking, throwing and kicking) are typically performed in a proximo‐distal sequence, where initially high proximal segments accelerate while distal segments lag behind, after which proximal segments decelerate while distal segments accelerate. The aims of this study were to examine whether proximal segment deceleration is performed actively by antagonist muscles or is a passive consequence of distal segment movement, and whether distal segment acceleration is enhanced by proximal segment deceleration. Seventeen skilled taekwon‐do practitioners were filmed using a high‐speed camera while performing a high front kick. During kicking, EMG recordings were obtained from five major lower extremity muscles. Based on the kinematic data, inverse dynamics computations were performed yielding muscle moments and motion‐dependent moments. The results indicated that thigh deceleration was caused by motion‐dependent moments arising from lower leg motion and not by active deceleration. This was supported by the EMG recordings. Lower leg acceleration was caused partly by a knee extensor muscle moment and partly by a motion‐dependent moment arising from thigh angular velocity. Thus, lower leg acceleration was not enhanced by thigh deceleration. On the contrary, thigh deceleration, although not desirable, is unavoidable because of lower leg acceleration.     

Information recall of younger and older skilled athletes: The role of display complexity,attentional resources and visual exposure duration

This study was concerned with the interactive role of experience of athletic skill with other relevant environmental variables (display complexity, attentional resources, exposure time of stimuli) on perception (recall) of structured handball game situations. Nineteen experienced (older) and 19 less experienced (younger) handball players were assigned randomly either to ball‐bouncing (diverted attention) or to calm seated (focused attention) conditions. In each of the two conditions, the subjects were exposed to a total of 36 slides containing 2–3, 5–6 and 8–10 players. Eighteen slides were exposed for 0.5 s and 18 for 1.0 s. All the slides contained structured defence and offence situations. Recall scores were subjected to repeated‐measures ANOVA using attention condition and age as between‐subject factors and task complexity and exposure duration as within‐subject factors. The results showed that the recall of less experienced players deteriorated more than the recall of more experienced players following exposure to complex displays (≥ 8 players) while engaging in a secondary task (bouncing). The findings suggest that research paradigms should be applied in the field of sport which share both ecological validity and a potential to discover the cognitive substrates underlying experience and age in skilled motor performance.     

数字地球：十五年发展与前瞻

“数字地球”理念产生至今已走过15年历程。以1999年和2009年分别发表的《数字地球北京宣言》为里程碑,数字地球科学技术发展纲领不断得到完善。人类正利用数字地球技术深入地认识地球、理解地球,进而合理开发和利用人类赖以生存的地球资源。7次国际数字地球会议和4次数字地球峰会的召开成功打造国际学术交流平台,促进全球发展。2012年,新一代数字地球理念应运而生,“数字地球”被赋予了新的理解与诠释,新一轮数字地球研究热潮正兴起,全球科技合作新模式将逐步建立。回顾历史,中国在应对数字地球带来的挑战方面是积极并卓有成效的。特别是在中科院的主导下,国际数字地球学会的建立,《国际数字地球学报》的创刊,中科院数字地球重点实验室的建立,数字地球科学平台的研发等,在全球数字地球发展历程中起到了重要的引领作用。面向未来,在大数据时代和数据密集型科学背景下,本文提出开展数字地球2030研究。     

中英文词表概念映射关系及处理方案研究*

从资源整合、跨语言检索的角度,介绍了词表互操作及概念映射的需求,分析了主要映射类型的研究情况,基于词表内聚合关系与映射类型的关联提出概念映射关系的几种处理方案,如基于等同关系及译项进行中英文同义词集及词义的相似匹配;基于词表内明确标明的组代关系及暗含的组配情况,推荐候选的复合等同映射;基于多重属分关系,推理一对多映射的候选语词;基于分类思想,解决专指概念与分面主题词、宽泛概念与基本大类的映射情况。此外,讨论了映射干扰的产生原因,如分类深度、多义项、语义关系矛盾、映射方向等。     

加强文明礼仪素养培养促进高校校园文化建设

具备良好礼仪素养的大学生,能有效展示个人魅力和涵养,同时彰显校园文化,有助于构建和谐校园,从而推动校园文化建设。而随着社会的不断变化,在大学生当中出现了一些不文明的行为,这些行为与校园文明礼仪的要求和校园文化建设的氛围很不和谐;同时,高校文明礼仪素养培养教学过程中也存在一些问题。本文阐述了礼仪素养培养对校园文化建设的重要意义,并指出了高校校园文化建设中学生礼仪素养培养存在的问题,同时,提出了加强校园文化建设过程中礼仪素养培养的方法。     

将绿色化学引入大学课堂

科技的发展带给我们丰富的物质资源同时也破坏了我们赖以生存的环境,危害着我们的身心健康。为了还我们一个健康的生活环境,从20世纪中叶开始人们提出了绿色化学的概念。绿色化学具有原子经济性的特点,可以实现零排放,并且节约资源,对环境起到很好的保护作用。在高校化学教学中渗透绿色化学知识不仅拓宽了学生的知识范围,更重要的是教会了他们如何去热爱环境、保护环境和治理环境,实现人与自然的和谐相处,推动人类社会的全面协调可持续发展。