A rule induction framework for the determination of representative learning design in skilled performance

Representative learning design provides a framework for the extent to which practice simulates key elements of a performance setting. Improving both the measurement and analysis of representative learning design would allow for the refinement of sports training environments that seek to replicate competition conditions and provide additional context to the evaluation of athlete performance. Using rule induction, this study aimed to develop working models for the determination of high frequency, representative events in Australian Rules football kicking. A sample of 9005 kicks from the 2015 Australian Football League season were categorised and analysed according to the following constraints: type of pressure, kick distance, possession source, time in possession, velocity and kick target. The Apriori algorithm was used to develop two models. The first consisted of 10 rules containing the most commonly occurring constraint sets occurring during the kick in AF, with support values ranging from 0.15 to 0.22. None of the rules contained more than three constraints and confidence values ranged from 0.63 to 0.84. The second model considered ineffective and effective kick outcomes and displayed 70% classification accuracy. This research provides a measurement approach to determine the degree of representativeness of sports practice and is directly applicable to various team sports.     

庄子摆脱社会之困的方法论探讨及其生态解读

庄子认为,人的一生都面临着命运、社会、自我以及环境等因素带来的难以摆脱的困境。其中,社会之困主要是指时势、儒家仁义等对人的限制或束缚。庄子对时势之困采取了安时处顺、无为而治的消解方法,对仁义之困采取了法天贵真、掊击圣人、以道释儒的化解策略。在庄子所采取的摆脱社会困境的种种策略和方法中所贯穿的都是顺物自然的生态学原则。     

Preparation time influences ankle and knee joint control during dynamic change of direction movements

The influence of preparation time on ankle joint biomechanics during highly dynamic movements is largely unknown. The aim of this study was to evaluate the impact of limited preparation time on ankle joint loading during highly dynamic run-and-cut movements. Thirteen male basketball players performed 45°-sidestep-cutting and 180°-turning manoeuvres in reaction to light signals which appeared during the approach run. Both movements were executed under (1) an easy condition, in which the light signal appeared very early, (2) a medium condition and (3) a hard condition with very little time to prepare the movements. Maximum ankle inversion angles, moments and velocities during ground contact, as well as EMG signals of three lower extremity muscles, were analysed. In 180°-turning movements, reduced preparation time led to significantly increased maximum ankle inversion velocities. Muscular activation levels, however, did not change. Increased inversion velocities, without accompanying changes in muscular activation, may have the potential to destabilise the ankle joint when less preparation time is available. This may result in a higher injury risk during turning movements and should therefore be considered in ankle injury research and the aetiology of ankle sprains.     

The Co-Effects of Query Structure and Expansion on Retrieval Performance in Probabilistic Text Retrieval

The effects of query structures and query expansion (QE) on retrieval performance were tested with a best match retrieval system (InQuery¹). Query structure means the use of operators to express the relations between search keys. Six different structures were tested, representing strong structures (e.g., queries with facets or concepts identified) and weak structures (no concepts identified, a query is a bag of search keys). QE was based on concepts, which were first selected from a searching thesaurus, and then expanded by semantic relationships given in the thesaurus. The expansion levels were (a) no expansion, (b) a synonym expansion, (c) a narrower concept expansion, (d) an associative concept expansion, and (e) a cumulative expansion of all other expansions. With weak structures and Boolean structured queries, QE was not very effective. The best performance was achieved with a combination of a facet structure, where search keys within a facet were treated as instances of one search key (the SYN operator), and the largest expansion.     

河南省高师体育院系开展网络教学的影响因素分析

文章运用文献资料法、问卷调查法、数理统计法、逻辑分析法等研究方法,分析了目前河南省高师体育院系网络教学过程中存在的实际问题,探讨了影响网络教学开展的主要因素,并提出了相应的对策,以期对当前河南省高师体育院系网络教学工作的顺利开展有所裨益。     

教师观念更新与教学模式改革创新的探讨——兼谈贯彻新《纲要》

实施新《纲要》要有创新精神,要更新观念、统一思想,才能创新体育课程教学模式,观念是否更新直接影响体育改革的质量。因此,高校体育教师更新观念是教学模式改革创新的前提,而教师素质的提高又是更新观念的基础。高校体育教师只有努力提高自身的综合素质,更新知识、转变观念,才能更好地实现新《纲要》的课程目标。     

Teachers’ conceptions of teacher-research and self-perceptions as enquiring practitioners—A longitudinal case study

Recognizing the importance teachers’ own voices play in their own professional development, the case study reported in this paper aims to illuminate the role that formal instruction and immersion in research can play in shaping teachers’ views of teacher-research and of themselves as future enquiring practitioners. The study was conducted with a group of nine overseas teachers attending a B.Ed. (Honours) degree in TEFL run by a higher education institution in Britain. Data were collected via questionnaires, semi-structured interviews and field notes from direct observation. Using a grounded theory methodology, the multiple sources of data were integrated into a theoretical model of ways of describing teacher research. The results of the study confirm previous assumptions that the highly-structured nature of the academic format of doing and reporting research may fall short of providing teachers with skills and tools for reflection that are easily transferable to practice.     

四连杆变幅机构平衡重系统的优化设计

本文介绍了一种四连杆变幅机构平衡重系统的优化设计方法。它将该系统的设计归结为五维、5个目标函教、9个约束条件的数学模型,应用改进的随机方向法求该数学模型的最优解。经改进的随机方向法,对于解决机构类优化设计中经常出现的反正弦、反余弦函数变量值大于1的问题提出了笔者的看法。 文中进行了实例计算,其结果较用传统方法得出的结果有显著进步,可直接应用于实际生产。     

金融发展对研发投资结构的影响分析

通过对融资约束、不同金融机构功能优势以及基础研究、应用研究、试验开发三类研发活动特点的分析,阐释了金融发展对三类研发活动的影响机理,同时结合面板模型回归结果得到：银行中介对基础研究、应用研究、试验开发三类研发活动投资强度的促进作用依次增强,股票市场对三类研发活动投资强度的促进作用依次减弱。这反映了二者的风险偏好及对研发投资活动的风险承能力不同,较之于股票市场,稳定经营的银行更偏向离市场近、且风险小的研发投资。基于目前中国研发投资内部结构比例不合理的现状,实现科技与金融的合理有机结合、提高基础研究在研发投资中的比重,关键是完善国内金融市场、优化金融结构,提高研发资金的配置效率。     

社会性别理论视角下的女大学生创业制约因素及其对策分析

大学生就业形势日趋严峻,女大学生就业难,已成为社会无法回避的现实问题。在国家以创业促进就业政策鼓励推动下,虽然越来越多的女大学生走上自主创业之路,但创业之路充满艰辛。本文基于社会性别理论视角,对江苏省48所高校46个本科专业660名创业女大学生进行了调查,对女大学生的创业特点、制约因素进行了深入分析后,提出了对策及建议。