Classification of individual articles from all of science by research level

A system of four research levels, designed to classify scientific journals from most applied to most basic, was introduced by Francis Narin and colleagues in the 1970s. Research levels have been used since that time to characterize research at institutional and departmental levels. Currently, less than half of all articles published are in journals that been classified by research level. There is thus a need for the notion of research level to be extended in a way that all articles can be so classified. This article reports on a new model – trained from title and abstract words and cited references – that classifies individual articles by research level. The model covers all of science, and has been used to classify over 25 million articles from Scopus by research level. The final model and set of classified articles are further characterized.     

大学生个人情况与抑郁症之间关系的Logistic回归分析

为了研究大学生个人情况与抑郁症之间的关系,本文对湖北武汉的华中师范大学、华中科技大学、中国地质大学、中南民族大学、华中农业大学、武汉理工大学等院校的6056名学生的个人情况与抑郁症情况进行了问卷调查;并对调查结果进行了Logistic回归分析,并发现其中9个因素对抑郁症的发病有显著影响;就其原因进行了简要的探讨,并与已有的结论进行了比较论证。研究结果为进一步研究大学生患抑郁症的诱因提供了科学依据,并对大学生抑郁症的防治有较好的指导意义。     

The Accomplishment Quotient Technic

The authors consider the problem of classifying an unknown observation into 1 of several populations by using tree-structured allocation rules. Although many parametric classification procedures are robust to certain assumption violations, there is need for classification procedures that can be used regardless of the group-conditional distributions that underlie the model. The authors discuss the tree-structured allocation rule. The tree rule is compared with linear discriminant and logistic regression procedures via Monte Carlo and real data analysis.     

浅析高校物流人才培养模式

物流人才的培养对于物流业的发展起着决定性的作用。根据我国物流人才的需求状况和我国物流人才培养的水平及存在的主要问题,紧紧抓住"实践"的培养方式,努力探索出适合我国国情和特色的物流人才培养的新模式。     

非财务因素变化对企业财务危机影响的实证分析

以深、沪两市2006～2007年被认定为财务状况异常的42家ST公司为财务危机样本,另选取与其一一对应的42家财务健康公司相配对,对股权结构、公司治理和审计意见等3个方面的8个非财务变量进行描述性统计．并运用logistic回归模型分别检验其对财务危机的解释力。研究结果表明,审计师意见的预警效果最好,年度股东大会出席率的影响次之,其他非财务变量均不显著。     

顶尖博士生科研绩效的影响因素研究

博士生科研绩效是博士生学习与科研活动成果的重要体现,直接反映其科研能力的高低,顶尖博士生必然有着非常突出的科研绩效。本文从个体因素、导师因素和培养机制等因素出发,以中国科学技术大学理学院已毕业的博士生为样本收集相关数据建立二值逻辑回归模型,研究影响顶尖博士生培养的关键点及作用机理。数据分析结果表明导师的学术经验、学术地位和所给予的指导量是顶尖博士生培养的关键点。中国高校可以提高导师队伍的整体科研能力,并将每位导师所带博士生的数量控制在一个合理的范围内,以培养出更多顶尖博士生。     

天津地方铁路数字专用调度通信系统

本文通过天津地方铁路数字专用调度通信系统介绍了铁路数字调度网的构成,系统信道分配及可靠性分析,数字调度的功能,以及今后发展使用过程中需要完善的问题,以与读者探讨。     

Country,School and Students Factors Associated with Extreme Levels of Science Literacy Across 25 Countries

A huge gap in science literacy is between students who do not show the competencies that are necessary to participate effectively in life situations related to science and technology and students who have the skills which would give them the potential to create new technology. The objective of this paper is to identify, for 25 countries, distinct subgroups of students with characteristics that appear to be associated with this proficiency gap. Data were based on the answers of 46,131 PISA 2006 students with scores classified below level 2 or above level 4, as well as the answers of their principals to school questionnaire and the OECD indicators of the financial and human resources invested in education at the national level for secondary school. The dependent variable of the analysis was a dichotomous variable the values of which represent the two different groups of students. The independent variables were the OECD indicators, and the items and indices derived from the student and school questionnaires. The analysis was based on classification trees and the findings were replicated and extended by the means of a multilevel logistic regression model. The results show that very specific levels of teachers’ salaries, parental pressure on schools, school size, awareness of environmental issues, science self-efficacy and socio-economic status have a very important role in predicting whether 15 year olds in OECD countries will belong to the lower or the highest proficiency groups as regards their aptitude in the context of life situations involving problems of a scientific nature.     

从唐代边塞诗看唐蕃关系的发展变化--唐代边塞诗系列研究之三

唐代边塞诗生动反映了唐蕃之间复杂多变的民族关系，和平亲善、和同一家使汉蕃两族和亲通婚、互派使，沟通情感，加强联络，使双方的经济化得以交流融合，但围绕着河湟、西域之争，唐蕃之间又纷争不休，战事不断，但无论怎样。汉蕃两族自古以来的血肉联系是无法割断的。     

在高校后勤社会化改革中做好学生思想政治工作

高校后勤社会化改革对加速高等教育事业起到了积极推动作用，但也给学生思想政治工作带来了新的情况和问题，提出了新的要求。章分析了高校后勤社会化改革为学生思想政治工作提供的新机遇、面临的新挑战，并从树立学生为主体的现代教育理念，构建学生思想政治工作新机制，强化育人意识，将制度建设与学生思想政治工作紧密结合，以及建立稳定的高素质的思想政治工作队伍等方面，探讨了新形势下学生思想政治工作的方法与途径。