结构方程与中国农村儿童入学的决定因素

中国农村儿童的入学率和辍学率到底是多少？哪些因素导致儿童辍学？家庭、社区和学生个人等诸方面因素作用辍学的路径是什么？使用2006年中西部地区20个县908名儿童的截面数据,运用SEM方法,考察教育供给、家庭教育支持、儿童在校表现和儿童失学之间的关系。结果发现,教育供给和儿童在校表现显著影响儿童失学,家庭教育支持对儿童失学不存在直接影响。通过儿童在校表现这一中介变量,教育供给和家庭教育支持同时间接作用于儿童失学。     

Mapping students' interest in a new domain: Connecting prior knowledge,interest, and self-efficacy with interesting tasks and a lasting desire to reengage

How students experience educational environments and the interconnections between their readiness, task experiences and their long-term desire to reengage with course content are critical questions for educators. Research postgraduate students (n = 310) at a research-intensive university in Hong Kong, engaging in a 24-h introductory teaching course, participated in this study. Learner readiness for the course was assessed as prior Domain interest, self-efficacy, and knowledge. Subsequently, students completed four formative assessments, reported their on-task interest in seven strategically chosen tasks and end-of-course Course and Domain interest. Longitudinal-SEM tested interconnections between readiness components, Task, Course and Domain interest. Initial self-efficacy beliefs for teaching predicted early Task interest, while Domain interest was a predictor of Task interest in explicitly practical task experiences. Strong interconnections between Task interest across the study were evident. Individual written and social discussion tasks presented strong contributions to future Course/Domain interest. Implications for theory and practice are discussed.     

Revisiting the Model Size Effect in Structural Equation Modeling

Fitting a large structural equation modeling (SEM) model with moderate to small sample sizes results in an inflated Type I error rate for the likelihood ratio test statistic under the chi-square reference distribution, known as the model size effect. In this article, we show that the number of observed variables (p) and the number of free parameters (q) have unique effects on the Type I error rate of the likelihood ratio test statistic. In addition, the effects of p and q cannot be fully explained using degrees of freedom (df). We also evaluated the performance of 4 correctional methods for the model size effect, including Bartlett’s (1950), Swain’s (1975), and Yuan’s (2005) corrected statistics, and Yuan, Tian, and Yanagihara’s (2015) empirically corrected statistic. We found that Yuan et al.’s (2015) empirically corrected statistic generally yields the best performance in controlling the Type I error rate when fitting large SEM models.     

花冠表面角质层对生药辛夷鉴定的意义

辛夷药材的使用一直比较混乱,本文首次尝试使用扫描电镜对望春花MagnoliabiondiiPamp.、武当玉兰M.sprengeriPamp.、玉兰M.denudataDesr.和紫玉兰M.lilifloraDesr.等4种植物的花冠表面角质层特征进行超微结构鉴别的研究,认为花冠表面角质层特征可以作为辛夷药材的鉴定依据。     

食蟹猴疟原虫卵囊扫描电镜研究

猕猴感染食蟹猴疟原虫子孢子产生速发和复发，利用扫描电子显微镜对速发型虫体卵囊和迟发型虫体卵囊进行了研究，结果发现速发型虫体卵囊和迟发型虫体卵囊有很大不同．速发型虫体卵囊壁光滑且较簿；而迟发型虫体卵囊壁较厚且有很多皱褶，而且有孔洞存在．认为两种类型的卵囊不是造成疟疾复发的原因，迟发型虫体卵囊上的孔洞不是在孢子逸出孔．     

基于SEM的科技型企业自主创新能力影响因素实证研究

应用技术创新理论、结构方程模型的方法,分析影响科技型企业自主创新能力的各种因素并针对诸因素对于自主创新能力的影响程度进行实证研究,最后提出相关建议.     

基于SEM模型的公安情报分析效能研究

[目的/意义]旨在为有效提升公安情报分析效能提供科学、客观、可靠的理论依据与实践指导.[方法/过程]详细探究了组织支持、感知行为控制、情报知识共享、外部约束性行为各潜在变量与公安情报分析效能之间存在的深层次内在联系.[结果/结论]构建了公安情报分析效能的SEM模型,并基于此提出提升公安情报分析效能的实践应用措施及方法.     

我国星级酒店业知识转化与核心能力形成的相关性研究

通过对我国星级酒店业知识转化与核心能力培育实践的现实性调查,借助于结构方程模型,揭示了我国星级酒店业知识转化在核心能力培育过程中的微观激励性机理,从而为我国星级酒店业进一步实施知识转化战略、有效地促进核心能力的培育提供了理论上的借鉴。     

基于结构方程模型的企业业务流程外包绩效评价研究

主要是对企业业务外包绩效进行定量的评价;目前关于企业业务流程外包绩效评价的研究方法有层次分析法、数据包络分析、模糊聚类分析法等,而将结构方程模型应用于企业业务流程外包绩效的评价却很少见,因此采用结构方程模型的方法对企业业务外包绩效进行研究;最后,在结构方程模型的实证研究结果下,构建了业务外包绩效评价模型,并且通过案例说明了该评价模型的使用方法,模型不但能对企业业务外包绩效进行定量的评价,而且为发包方提高企业的绩效提供了理论依据。     

电磁振动对金属粉末注射型坯结构均匀性的影响

把电磁振动技术引入到金属粉末注射成型中,在一定的工艺条件下,逐步调节振动频率和振幅,制备出不同振动条件的注射型坯,并通过SEM等实验手段对型坯的物料分散状态和微观结构进行研究,以探讨振动频率和振幅对型坯微观结构的影响。结果表明：施加振动后,型坯微观结构均散程度大大提高,且随着振动频率或振幅的不断增大,均散程度逐渐达到最好后,均匀和完善程度有所降低,但仍然好于稳态成型时的状态。