Use of place information for improved event tracking

The main purpose of topic detection and tracking (TDT) is to detect, group, and organize newspaper articles reporting on the same event. Since an event is a reported occurrence at a specific time and place and the unavoidable consequences, TDT can benefit from an explicit use of time and place information. In this work, we focused on place information, using time information as in the previous research. News articles were analyzed for their characteristics of place information, and a new topic tracking method was proposed to incorporate the analysis results on place information. Experiments show that appropriate use of place information extracted automatically from news articles indeed helps event tracking that identify news articles reporting on the same events.     

Optimization of some factors affecting the performance of query expansion

This paper examines the factors affecting the performance of global query expansion based on term co-occurrence data and suggests a way to maximize the retrieval effectiveness. Major parameters to be optimized through experiments are term similarity measure and the weighting scheme of additional terms. The evaluation of four similarity measures tested in query expansion reveal that mutual information and Yule's Y, which emphasize low frequency terms, achieve better performance than cosine and Jaccard coefficients that have the reverse tendency. In the evaluation of three weighting schemes, similarity weight performs well only with short queries, whereas fixed weights of approximately 0.5 and similarity rank weights were effective with queries of any length. Furthermore, the optimal similarity rank weight achieving the best overall performance seems to be the least affected by test collections and the number of additional terms. For the efficiency of retrieval, the number of additional terms needs not exceed 70 in our test collections, but the optimal number may vary according to the characteristics of the similarity measure employed.     

虚拟R＆D网络组织边界分析

虚拟R＆D网络组织边界问题是理解当代科学技术活动演化的重要问题.结合组织网络化发展的趋势,分析了组织边界的内涵,并在此基础上讨论了如何界定虚拟R＆D网络组织的边界,还对决定虚拟R＆D组织边界的重要因素做了进一步的研究,以期深化对这一问题的理解。     

量化数字人文综述

数字人文对多样化研究内容、语言和学者的包容性,使其在近20年得到突飞猛进的壮大,并逐渐涉及人文学、社会学、计算机科学等多个领域。然而,包容的“大帐篷”不仅在一定程度上限制了对数字人文具体学科内容、科研范畴、学者群体和学科历史的理解,也使得学科成长和拓展缺少客观数据和理论的支持,从而无法健康且可持续地发展。文章回顾前人对数字人文所做的学科研究,重点集中在使用计量和统计等方法来揭示数字人文的知识结构、内容演变、合作模式和学者背景等工作上,以期帮助学界从量化的角度认识数字人文的形成、发展和前景。     

中国图书馆市场分析及拓展策略

国内的图书馆主要分为四种类型:高校图书馆、公共图书馆、中小学图书馆、科研单位及企事业单位资料室.据资料显示,目前全国共有公共图书馆2736个(引自《"十五"时期我国社会事业发展的基本情况和特点》一文),普通高校图书馆1792个(根据《中国教育事业发展状况》分析得出),这两个数据是比较准确的,同时这也是国内图书馆市场的主要组成部分.     

Genetic analysis of fruit shape traits at different maturation stages in sponge gourd

The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits （fruit length and fruit perimeter） in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage （1-12 d after flowering） for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage （13-60 datter flowering）. The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage.     

浅谈新课改下的高中英语教学目标设计

教学目标的设定要考虑横向领域和纵向层级,而实用的高中英语教学目标应从三维阐述,具体的陈述应反应学生要习得的结果。     

高校实验室安全与环保教育方式和内容的思考

分析了高校实验室安全事故发生的因为、实验室安全与环保教育的主要对象、高校开展实验室安全与环保教育的重要性与紧迫性,在此基础上探讨了高校实验室安全与环保教育常规化、日常化、持久化的方式与内容,促进实验室与平安校园的建设.     

经管类学院多层一体化综合实验室构建研究

分析了经济管理类学院实验室建设存在的问题.结合学科特点,提出构建以网络技术为支撑、不拘泥于学科界限和物理空间,集学科融合、人才培养、科学研究于一体的多层一体化综合实验室,细述了构建思路和实现方案.     

模态试验分析在教学中的应用和实践

模态试验分析是了解结构动态特性的有效手段.通过模态试验,可以计算出结构的固有频率、模态振型、阻尼比等参数,为结构设计与优化打下坚实的基础.在实验教学中,通过对模态试验的基本原理、主要步骤和试验中注意事项的介绍和分析,可以指导学生完成模态实验,加深学生对理论知识的理解和掌握,提高学生的动手能力、独立思考能力和分析解决问题的能力.