后危机时代中美信息技术投资替代作用的结构特征——基于CES Copula 贝叶斯估计方法

技术进步是当今经济增长的主要推动力,信息技术投资亦是各个国家提高经济效率的主要手段和投资方向。本文旨在分析信息技术对传统资本、劳动力的交互作用是否会随着投资强度和发展阶段而改变,通过Copula贝叶斯估计法,利用经验数据对比,分析我国与美国在信息技术,资本、劳动力投资交互作用的结构性特征,经过对比发现,我国信息技术对我国资本、劳动力的替代效应明显弱于美国,且呈现中心区域增强的替代作用。信息技术投资替代性的结构性差异值得我们深入研究,以免过高或低的估计信息技术价值,对于国家层次的信息技术投资决策具有重要作用。     

Levels and statistical analysis of aerosol phase PAHs over Qingdao alongshore

Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured during various seasons at six different cities/locations in Qingdao alongshore. The annual average PAHs concentration ranged from 16 ng/m3 (at a clean com- pared site) to 308 ng/m3 (in an industry site). The average total particulate PAHs concentration was 74.5 ng/m3 with a higher concentration of particulate PAHs in winter. Based on a year-round dataset, the sources of PAHs in the air of Qingdao were drawn by principal factor analysis and correlation analysis. The results indicated that vehicle emissions and oil burning were the main source of PAHs in Qingdao alongshore.     

论大学课堂里启发式教学

本文探讨了大学课堂里运用启发式教学的三种方式,不完全归纳式,关联式和直观式。通过对概率统计课程中部分知识点的讲授为例,详细阐述了这些方法的运用和实施,并对教师的要求做了相关的探讨。     

高中生学业成绩因素的交互作用

文章探讨影响高中生学业成绩的各因素的交互作用。用追溯回归法分析各因素与学业成就的交叉时序，通过显著性检验，探索各因素的变动对学业成绩的影响，并对高中生在不同年级、不同性别的学习各因素及学业成绩进行比较。结果表明：高中生的学习各因素水平之间呈正相关，而与学业成绩相关不显著；高中生学习的动力因素、个性因素变动对学业成绩的影响显著，而技术因素、环境因素的变动对学业成绩的影响不显著；高一与高二的学习各因素没有差异，而学业成绩则呈显著差异；高中男生与女生的动力因素、个性因素、技术因素呈显著差异，而在环境因素、学业成绩的差异则不显著。     

“十二五”以来中国创新政策效果评价与政策启示

构建过程导向的因子理想关联评价模型和结果导向的三阶段DEA效率评价模型,对"十二五"以来的创新政策效果做评估,发现2010-2018年科技创新政策整体是有效的,但主要影响因子存在地区差距较大、有效性波动等问题;政策效果出现东西差距缩小、南北差距拉大、东北明显落后、中西部依赖性强等特点;创新效率由中心城市到经济圈再到其他地区递减.检验近年创新政策实施效果,对制定"十四五"创新政策有重要的参考价值.     

In situ hyperspectral data analysis for pigment content estimation of rice leaves

INTRODUCTIONPigmentsarecloselyrelatedtothephysiolog icalfunctionofleaves.Chlorophyllsabsorblightenergyandtransferitintothephotosyntheticpro cess.Carotenoids (yellowpigments)canalsocontributeenergytothephotosyntheticsystem .Becauseoftheimportanceofpigments…     

高等数学对关联基础课的相关性影响

通过对学生成绩的抽样统计,采用数理统计分析方法得出高等数学对相关基础课--大学物理、线性代数、概率论与数理统计的成绩都有影响,从而肯定了高等数学在理工科学科中的基础性地位.     

Mission impossible? Reflecting upon the relationship between physical education,youth sport and lifelong participation

It is widely believed that school physical education (PE) is or, at the very least, can (even should) be a crucial vehicle for enhancing young people's engagement with physically active recreation (typically but not exclusively in the form of sport) in their leisure and, in the longer run, over the life-course. Despite the prevalence of such beliefs, there remains a dearth of evidence demonstrating a ‘PE effect’. Indeed, the precise nature of the relationship between PE, youth¹1. Youth is defined as a life-stage that in chronological terms can be very broadly mapped onto the latter teenage years, with some leeway at the upper end to include the post-teen years up to young adulthood. Thus, youth is regarded as a period of transition ranging from roughly 15 to 25 years. For the purposes of this article, the emphasis will be on the latter secondary school years. sport and lifelong participation is seldom explored other than in implicit, often speculative and discursive, ways that simply take-for-granted the positive effects of the former (PE) on the latter (youth and adult participation in sport and physically active recreation). Using largely European studies to frame the issue, this article reflects upon the supposedly ‘causal’ relationship between PE, youth sport and lifelong participation and, in doing so, highlights the inherent problems associated with attempts to identify, characterise and establish a ‘PE effect.’ In the process, the article points to a need for more longitudinal and biographical research exploring sports careers and the sporting habituses of young people, not least in order to better understand in precisely what circumstances PE interventions might work to enhance youth involvement in sport and physical activity and, subsequently, lifelong participation.     

区域竞技体育发展现状与社会人口结构的相关研究

分别以我国六大区域(华北、东北、华东、中南、西南、西北)为研究对象,运用文献资料、数理统计和逻辑分析等方法,对区域竞技体育现状与社会人口结构(职业、城乡、文化、年龄、发展及分布结构)进行相关分析.结果表明:传统型人口产业结构是制约我国竞技体育发展的重要因素,发展型和现代型人口产业结构对竞技体育发展具有积极影响.竞技体育与非农业人口成正向关系,与农业人口成反向关系.竞技体育与高文化程度人群存在显著正相关.年轻型人口社会可为竞技体育发展提供人才储备,成年型人口社会是竞技体育发展的"黄金时期",而老年型人口社会可能制约竞技体育的发展.人口发展结构与竞技体育呈负相关,人口分布结构也可通过一些渠道影响竞技体育.