一类基于混沌系统的图像加密算法

混沌序列具有容易生成、对初始条件敏感、以及具有白噪声等统计特性。文章基于logistic映射所产生的混沌序列,提出一种新的图像加密算法,通过计算机实验仿真表明,该算法具有良好的加密效果。     

学习型社会教育资源组织与配送模式构建——以服务业从业人员为例

21世纪的终身学习的特点就是“以学习者为中心”,在社会教育资源越来越丰富的时代,需要对社会教育资源进行有效整合,服务于学习型社会。根据服务业就业门槛低等特征,文章构建了一个包括学习方案研究中心、配送中心、传播网络和渠道、有效的学习评估系统等构成部分的学习型社会教育资源的组织与配送模式。     

基于Logistic模型的中国国家能源消费总量预测研究

建立算法优化后的中国国家能源年度消费总量Logistic模型,并以2003年至2010年中国国家能源消费年度统计数据为基础,对中国未来20年的能源消费情况进行研究和预测,2015年、2020年、2030年分别为38.46亿吨标准煤、41.13亿吨标准煤和42.50亿吨标准煤,能源消费弹性系数呈逐年下降趋势,指出我国能源消费发展趋势,提出我国能源政策建议。     

Cognitive,Affective, Personality,and Demographic Predictors of Foreign-Language Achievement

Abstract

The ability of cognitive, affective, personality, and demographic variables to predict second-language acquisition among college students was investigated. An all possible subsets regression analysis was used to compare the proportion of variance in foreign-language achievement explained by each variable. The analysis revealed that variables from each of the 4 domains were important predictors of foreign-language achievement. Overall, academic achievement, as measured by GPA average, was the best predictor, explaining 11.5% of the variance in foreign-language achievement. Foreign-language anxiety, the next best predictor, explained 10.5% of the variance. The educational implications of these findings for understanding foreign-language achievement are discussed, along with suggestions for future research.     

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。