待证结论构造辅助函数法

按待证结论构造辅助函数法对解答微积分中一类题是一种有效的方法,它提供了一种创造性思维模式,是逆向思维的一个很好的方法。     

女子足球运动员注意瞬脱特征的实验研究

为揭示女子足球运动员的注意瞬脱特征,采用自行开发的测试软件对20名女子足球运动员和38名普通体育女大学生的注意瞬脱特征进行测试,结果发现,女子足球运动员注意瞬脱出现的时间点、注意瞬脱持续时间、注意瞬脱程度都与普通体育女大学生之间存在非常显著的群体差异.     

传统武术与现代武术(散打)在技击特征上的差异研究

从多角度对传统武术和现代武术散打进行比较，分析了传统武术在技击特征上的弱点和现代武术散打的优势，有利于更好地体现传统武术中“攻防含义”的艺术魁力，使武术套路和武术散打在现代体育领域里发挥更大的积极作用。     

基于主成分分析法的科技期刊评价方法

针对目前科技期刊评价方法中存在的指标之间相关性问题和指标权重选取问题,提出了基于主成分分析的科技期刊评价方法.该评价方法通过相关系数矩阵的特征向量将评价指标线性变化成彼此独立的主成分,根据主成分累计贡献值确定主成分的取用维数,由主成分方差确定权重.其优点是:可以消除由于指标间的相关性带来的偏差,降低计算维数,从而降低指标选择的难度,提高评价结果的可信度;此外,可以消除人为确定指标权重引起的弊病,使评价结果更具客观性和准确性.     

读者利用图书馆的平等权利的衡量方法

如何对一个社会或地区甚至是某个图书馆在保障读者平等地利用图书馆的权利方面进行评价？在什么情况下,可以说读者的这种权利得到了改善？在定义读者群体的差别性的基础上,遵循J．罗尔斯（1988）的思路,指出平等权的实现程度取决于“最小受惠者”时图书馆的利用。     

大学评价指标国内外差异原因分析

从大学评价指标的重要性入手,对国内、外7所大学评价主体的评价指标从社会大众认知差异方面、国家相关的教育与行政法律、法规与政策方面和大学评价研究及发布主体单位差异三个方面的原因进行了比较分析。     

Spread or Sacrifice: Dilemma for Lighting Policies

ABSTRACT

Light sensitive objects will fade on display. Collection managers and curators face the dilemma whether to spread fading over several similar objects or sacrifice one. This paper describes an experiment in which participants were asked how they would want to pass on a collection of seventeenth century hand-coloured maps to coming generations. Results show that while colour changes are hardly visible, both public and professionals do not perceive them as damage and prefer to spread fading. Once fading becomes clearly visible in all maps, the preference shifts to sacrificing one map. The tipping point lies around five just noticeable changes. This information can be used when selecting objects for exhibition. The outcome also implies it would be prudent to assess the degree of fading of much exhibited objects and consider whether and when to choose for a sacrifice strategy.     

Research universities on the ResearchGate social networking site: An examination of institutional differences,research activity level,and social networks formed

As one of the largest active academic social networking sites, ResearchGate (RG) has been utilized by scholars to share publications, seek collaborators, communicate work in progress, and build scholarly reputation. This study collects data from RG users from 61 U.S. research universities at different research activity levels, as categorized by the Carnegie Classification of Institutions of Higher Education, to examine the impact of institutional differences on RG reputational metrics. The results confirm that RG is a research-oriented academic social networking site that closely and realistically mirrors the research activity level of institutions. With an increase in the research activity level of a university, its affiliated RG users tend to have higher RG scores, more publications and citations, and more profile views and followers, while the average number of reads of their publications and followees tend to be lower and fluctuant. In addition, RG users primarily follow others from institutions of a higher research activity level, forming virtual social networks centered around esteemed institutions. The study suggests academic social networks can serve as indicators in evaluation of research activities among research institutions, and such sites can be helpful and credible for acquiring resources, keeping informed about research, and promoting academic influence.     

影响雪与滑板摩擦系数的几种因数的研究

介绍了雪与滑板的测量系统和利用单片机对数据采集系统。为了提高实验精度,对光电门进行了改进,大大缩短了电平跳变时间,同时对雪与滑板之间的摩擦系数作了比较系统的实验研究。实验结果为制作雪的模型材料提供了基本依据。     

Comparing the magnitude and direction of asymmetry during the squat,countermovement and drop jump tests in elite youth female soccer players

ABSTRACT

The aims of the present study were to provide an in-depth comparison of inter-limb asymmetry and determine how consistently asymmetry favours the same limb during different vertical jump tests. Eighteen elite female under-17 soccer players conducted unilateral squat jumps (SJ), countermovement jumps (CMJ) and drop jumps (DJ) on a portable force platform, with jump height, peak force, concentric impulse and peak power as common metrics across tests. For the magnitude of asymmetry, concentric impulse was significantly greater during the SJ test compared to CMJ (p = 0.019) and DJ (p = 0.003). No other significant differences in magnitude were present. For the direction of asymmetry, Kappa coefficients revealed fair to substantial levels of agreement between the SJ and CMJ (Kappa = 0.35 to 0.61) tests, but only slight to fair levels of agreement between the SJ and DJ (Kappa = ?0.26 to 0.18) and CMJ and DJ (Kappa = ?0.13 to 0.26) tests. These results highlight that the mean asymmetry value may be a poor indicator of true variability of between-limb differences in healthy athletes. The direction of asymmetry may provide a useful monitoring tool for practitioners in healthy athletes, when no obvious between-limb deficit exists.