Measuring Search Engine Quality

The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures.     

促进高校体育教师科学研究水平的方法与措施

高校体育教师的生命力来自于体育科学研究。高校体育教师必须与体育科学研究紧密的联系在一起。高校体育科学研究就是以高校体育教育现象和体育教育问题为对象,运用科学研究的原则和方法,探寻体育教学规律及有体育教育途径和方法的科学实践活动.努力提高高校体育教师的体育科学研究水平,有利于提高高校体育教师的整体素质,有利于教育科研的发展,提高教育质量。     

关于科技论文关键词标引的问题与对策

在对关键词进行一般描述的基础上,论述了科技论文关键词标引的意义,分析目前科技论文关键词标引中存在的问题,并提出相应的对策.     

对大学生健康教育的思考

根据健康新观念和针对当前大学生存在的各种非健康性表现，阐述大学生健康教育的必要性，并对大学生健康教育问题进行思考和提出建议。     

模拟海拔2000m和3000m高原训练的不同时程对大鼠骨骼肌蛋白质代谢的影响

用低压氧舱模拟海拔2 000 m、3 000 m高原低氧环境对大鼠进行耐力训练,探讨不同海拔高原训练1周及返回平原训练1～2周对大鼠骨骼肌蛋白质代谢及肌糖原和血清睾酮含量的影响.研究发现:海拔2 000 m、3 000 m高原耐力训练导致大鼠骨骼肌蛋白质分解代谢显著加强,肌糖原含量显著提高,并有随高度增加而加强的趋势,但血清睾酮含量无明显变化;返回平原后骨骼肌蛋白质代谢第1周迅速恢复到正常状态,第2周保持稳定,肌糖原含量第1周下降,第2周显著回升,而血清睾酮含量均无明显变化;实验支持高原训练的高度应选择在2 000 m～3 000 m之间、回平原参赛时间应选择在2周左右的观点.     

试论足球队中核心队员组织能力的培养

通过分析足球队中核心队员的组织能力对整个球队建设与成功的作用和影响 ,论述了足球队中核心队员组织能力培养的重要性 ,并就核心队员组织能力的培养提出自己的看法。     

Reprographic rights in Singapore: the story of CLASS

The Copyright Licensing and Administration Society of Singapore was established in 1999. It is now profitable and commercially significant, perhaps uniquely so in Asia. Critical factors in its growth have included a statutory (non‐voluntary) photocopying licence provision for educational institutions in the Copyright Act; and widespread support from the local and international communities of rightsholders. Tentative consensus has been established with educators over a fair level of remuneration for copying. Further work needs to be done to extend or amend the current model for electronic copying, for the private sector and for other countries in the region.