2003年全国武术套路冠军赛女子长拳难度动作完成情况分析

武术套路难度动作是整套动作的主体。难度动作完成的好坏是反映运动员技术水平高低和整套动作技术价值的主要依据。运动员在参赛时,也特别注意难度动作的选择、完成的质量,并且力求合理地把它们布局在全套动作中。对2003年全国武术套路冠军赛(女子赛区)长拳难度动作完成质量进行分析、研究,并找出其影响因素,对提高长拳套路难度动作完成质量,促进武术运动科学化训练具有十分重要的现实意义。     

2002年全国健美操锦标赛难度动作分析

通过现场观看比赛和录像观察,对2002年全国健美操锦标赛的男子单人和女子单人项目的前8名的成套动作中的难度动作数量、组别、分值、C组难度动作空中姿态类型,进行统计分析.结果表明,目前我国运动员的成套动作中所选择的四个组别难度动作的比例基本合理,且符合运动员各自的身体素质能力和训练水平,完成质量比往年有很大的提高.但在C组跳与跃类难度动作的选择上缺乏多样性,存在着较多的空中姿态重复现象,与竞技健美操最新发展趋势有一定的差距.     

国际评分规则的修改对竞技健美操技术发展的影响

运用比较分析的方法对国际体联健美操技术委员会所颁布的全部版本的竞技健美操评分规则中的完成与难度部分的修改进行研究,结果表明规则的演变引导健美操技术逐渐向竞技级别化的方向发展;对于成套动作中所采用的难度动作的编排和完成质量提出了更高的要求。     

2002年全国健美操锦标赛难度动作分析

通过现场观看比赛和录像观察，将2002年全国健美操锦标赛的男子单人和女子单人项目的前8名的成套动作中的难度动作数量、组别、分值、C组难度动作空中姿态类型，进行统计分析。结果表明：目前我国运动员的成套动作中所选择的4个组别难度动作的比例基本合理，且符合运动员各自的身体素质能力和训练水平，完成质量比往年有很大的提高。但在C组跳与跃类难度动作的选择上缺乏多样性，存在着较多的空中姿态重复现象，与竞技健美操最新发展趋势有一定的差距。     

One hundred and fifty years of sprint and distance running – Past trends and future prospects

Sprint and distance running have experienced remarkable performance improvements over the past century. Attempts to forecast running performances share an almost similarly long history but have relied so far on relatively short data series. Here, we compile a comprehensive set of season-best performances for eight Olympically contested running events. With this data set, we conduct (1) an exponential time series analysis and (2) a power-law experience curve analysis to quantify the rate of past performance improvements and to forecast future performances until the year 2100. We find that the sprint and distance running performances of women and men improve exponentially with time and converge at yearly rates of 4% ± 3% and 2% ± 2%, respectively, towards their asymptotic limits. Running performances can also be modelled with the experience curve approach, yielding learning rates of 3% ± 1% and 6% ± 2% for the women's and men's events, respectively. Long-term trends suggest that: (1) women will continue to run 10–20% slower than men, (2) 9.50 s over 100 m dash may only be broken at the end of this century and (3) several middle- and long-distance records may be broken within the next two to three decades. The prospects of witnessing a sub-2 hour marathon before 2100 remain inconclusive. Our results should be interpreted cautiously as forecasting human behaviour is intrinsically uncertain. The future season-best sprint and distance running performances will continue to scatter around the trends identified here and may yield unexpected improvements of standing world records.     

Will Obama's My Brother's Keeper and Similar Initiatives Have a Positive Impact on Low-Income Students?

Barack Obama's My Brother's Keeper is designed to narrow persistent gaps that boys and young men of color confront often and to help all young people achieve their potential in college and career. An important part of this initiative is comprehensive mentoring that supports students in schools and in communities. Because ethnic-minority students have extremely low graduation rates in high school and college, an essential question is addressed: Can My Brother's Keeper and similar initiatives with a mentoring component be effective in helping minority students to achieve success in elementary and secondary schools and in college?     

非对称损失下单边截断分布族参数的经验Bayes检验及其收敛速度

在一种非对称损失下,构造了一类单边截断型分布族参数的经验Bayes检验,建立其收敛速度,在一定条件下证明了它的收敛速度可以任意接近于1/2。最后给出满足定理条件的一个例子。     

《秋水庵花影集》的成书及版本考论

《秋水庵花影集》是晚明散曲大家施绍莘现存可知的唯一的一部作品集,它成书的每一个环节无不浸润着施绍莘的心血。由于施绍莘的精心安排,明刻本《秋水庵花影集》呈现出了独特的面貌。     

一类投资组合模型的模糊两阶段算法

对多目标证券组合投资模型进行了研究，模型以风险损失率作为风险。该模型是一多目标线性优化问题．我们采用模糊折衷算法对模型进行了求解，算例给出了该模型的一个实例的最优解。