Reliably Assessing Growth with Longitudinal Diagnostic Classification Models     

Matthew J. Madison 《Educational Measurement》2019,38(2):68-78

Recent advances have enabled diagnostic classification models (DCMs) to accommodate longitudinal data. These longitudinal DCMs were developed to study how examinees change, or transition, between different attribute mastery statuses over time. This study examines using longitudinal DCMs as an approach to assessing growth and serves three purposes: (1) to define and evaluate two reliability measures to be used in the application of longitudinal DCMs; (2) through simulation, demonstrate that longitudinal DCM growth estimates have increased reliability compared to longitudinal item response theory models; and (3) through an empirical analysis, illustrate the practical and interpretive benefits of longitudinal DCMs. A discussion describes how longitudinal DCMs can be used as practical and reliable psychometric models when categorical and criterion‐referenced interpretations of growth are desired.  相似文献   

地球椭球模型中太阳位置计算的改进     

李文  赵永超 《中国科学院大学学报》2019,36(3):363-375

准确高效的太阳位置计算在遥感辐射定标、太阳能获取等多个领域具有重要应用价值。针对传统太阳赤纬角算法对不同年份数据差异考虑不足的问题，采用数值拟合法提出适用于不同年份的改进公式。根据误差曲线所呈现的周期性，采用傅里叶展开法提出以4年为周期的赤纬角改进算法，并推导出地球椭球模型下的太阳高度角公式。蒙气差影响太阳位置观测与计算。针对传统蒙气差算法在低仰角下误差较大的问题，提出0°~30°仰角下蒙气差的改进公式。把改进算法与相应的传统算法进行误差对比，结果表明，改进算法在太阳赤纬角、太阳高度角、低仰角下蒙气差计算的误差均明显降低，计算过程简单高效，符合相关工程项目应用需求。  相似文献   

Online visibility of software-related web sites: The case of biomedical text mining tools     

Gael Pérez-Rodríguez  Martín Pérez-Pérez  Florentino Fdez-Riverola  Anália Lourenço 《Information processing & management》2019,56(3):565-583

  相似文献   

The biomechanical characteristics of high-performance endurance running     

Stephen J. Preece  Christopher Bramah  Duncan Mason 《European Journal of Sport Science》2019,19(6):784-792

The biomechanical profile of high-level endurance runners may represent a useful model that could be used for developing training programmes designed to improve running style. This study, therefore, sought to compare the biomechanical characteristics of high-performance and recreational runners. Kinematic and kinetic measurements were taken during overground running from a cohort of 14 high-performance (8 male) and 14 recreational (8 male) runners, at four speeds ranging from 3.3 to 5.6?m?s^?1. Two-way ANOVA analysis was then used to explore group and speed effects and principal component analysis used to explore the interdependence of the tested variables. The data showed the high-performance runners to have a gait style characterised by an increased vertical velocity of the centre of mass and a flight time that was 11% longer than the recreational group. The high-performance group were also observed to adopt a forefoot strike pattern, to contact the ground with their foot closer to their body and to have a larger ankle moment. Importantly, although observed group differences were mostly independent of speed, the tested variables showed a high degree of interdependence suggesting an underlying unitary phenomenon. This is the first study to compare high-performance and recreational runners across a full range of kinematic and kinetic variables. The results suggest that high-performance runners maintain stride length with a prolonged aerial phase, rather than by landing with a more extended knee. These findings motivate future intervention studies that should investigate whether recreational runners could benefit from instruction to decrease shank inclination at foot contact.  相似文献   

“三个转型”综合改革：新时代世界一流体育大学发展的历史选择     

曹卫东 《北京体育大学学报》2019,42(1):17-22

摘要：新时代是我国发展新的历史方位，体育强国、教育强国、健康中国三大战略为世界一流体育大学提出了新的更高要求。为此，北京体育大学提出了“三个转型”综合改革，以推进世界一流体育大学建设和高水平竞技体育后备人才培养基地建设，为国家培养勇担新时代体育事业发展重任的优秀人才。为实现上述目标，应在深刻认识“三个转型”改革提出的背景基础上，深入理解“三个转型”的内涵与目标，全面推进“三个转型”综合改革，为新时代体育、教育事业贡献北京体育大学的力量。研究背景包括：1）新时代是“三个转型”的历史坐标，2）强国战略是“三个转型”的现实依据，3）创新模式是“三个转型”的客观需要；“三个转型”分别是：1）全面推进从传统经验型体育大学向现代科技型体育大学转型，2）从以夏季项目为主的体育大学向夏季冬季项目全面发展的体育大学转型，3）从本土化体育大学向国际化体育大学转型，其目的是实现两大办学目标：1）把北京体育大学建成中国高水平竞技体育后备人才培养基地，2）把北京体育大学建设成为世界一流体育大学；为了实现“三个转型”转型及其目标，必须准确把握“办大学与建基地、文化传承与科技创新、立足中国与放眼世界”三个维度及其核心关键问题。  相似文献   

Transforming in the visiting assistant professor role: collaborative self-study research in physical education teacher education     

James D. Ressler  K. Andrew R. Richards 《Sport, Education and Society》2019,24(5):507-519

Transitioning into faculty roles can be a challenging experience. Responsibilities related to teaching, research, and service can be difficult to balance, and mismatch between personal preferences for work focus and instructional expectations can be problematic. This is particularly true of visiting assistant professors who want to work toward tenure-track positions, but whose current job focus is on teaching. Through transformative learning theory and employing the methodologies of self-study, we sought to understand the experiences of Kevin, the second author and a first-year visiting assistant professor. We draw data from Kevin's reflective journal and discussions between Kevin and his critical friend, Jim. Themes included (a) becoming an academic, (b) a hard-wired disposition toward work, and (c) influence of the VAP on emotional and personal health. Results are discussed through the lens of transformative learning theory and focus on Kevin's growth during his year as a visiting assistant professor.  相似文献   

体育文化交流对中美关系改善的作用及启示——基于中美建交40年的历史考察     

肖焕禹  倪京帅 《武汉体育学院学报》2019,53(10):12-18

运用文献资料等研究方法，基于"契机-轨迹"理论，对中美建交40年来体育文化交流情况进行了回顾和梳理，分析了外交政策导向下中美体育文化交流"契机"的形成和"轨迹"的发展，解读中美建交的历史背景和体育文化交流的特征与价值。认为：在"和平与发展""构建开放合作和谐社会""新时代构建新型国际关系"外交政策的影响下，中美体育文化交流具有体育文化财富的共享性、体育竞技的对等性、体育文化交流的公共性特征；中美体育文化交流促进中美建交，促进中美和平发展；改变世界格局，获得话语权；树立国家形象，展示大国责任；深化体育改革，促进社会发展。  相似文献   

体育赛事转播权的多重解读及其类型化保护     

龚韬  刘智瑜  何炼红 《武汉体育学院学报》2019,53(11):43-48

体育赛事转播权是一种新兴的复合型权利，是指电视台、视频网站、直播平台等转播机构就其制作的体育赛事节目和提供的转播信号享有的著作权或者录音录像制品权、广播组织权，同时也是指赛事组织者就体育赛事享有的"转播许可权"。对其不同层次的内容应当分别予以解读，而不宜笼统地在"体育赛事转播权"这一概念下进行讨论。对赛事组织者的权利保护，有赖于体育法对其权利予以法定化；对相应的著作权人和邻接权人的保护，需要在完善著作权法的基础上，坚持作品独创性判断标准，并提升邻接权的保护水平。  相似文献   

基于单向流固耦合的不同风速下帆板帆翼空气动力性能仿真     

雷晓珊  马勇  蔺世杰 《武汉体育学院学报》2019,53(11):95-100

目的：探究不同风速对帆板帆翼结构以及周围流场的影响。方法：以奥运女子级别的Neil Pryde RS：X帆板帆翼为研究对象，考虑空气动力与结构的流固耦合效应，利用ANSYS Workbench进行单向流固耦合分析。结果：Realizable模型适合计算帆翼周围的流场湍流度，在风速为2m/s时帆翼升阻比最大；随着风速的增大，帆翼面发生变形和振动会导致风激振现象、背风面产生明显的涡脱现象，且帆翼表面应力区增大，全帆的应变逐步增加。结论：不同风速下的帆翼迎风面和背风面的压力分布、帆翼整体空气动力有一定差异，运动员比赛中应该根据当时风况调整帆翼参数。  相似文献   

Association between psychosocial stressors with emotional and behavioral problems among children of low-income addicted families living in Brazil     

《Child abuse & neglect》2019

BackgroundChildren exposed to substance use in their families are vulnerable to multiple risk factors in their development and at increased risk for emotional and behavioral problems. The aims of the study were as follows 1) estimate the prevalence of emotional and behavioral problems among children aged 6–11 years old, living with addicted family members in a low-income urban community of São Paulo, Southeastern Brazil; 2) evaluate the children’s exposure to family psychosocial stressors and substance use; and 3) investigate the factors related to the increased risk of emotional and behavioral problems and substance use.MethodsA cross-sectional study was conducted among 101 children aged 6–11 years old (M = 9.16 years, SD = 1.61). The instruments used were a sociodemographic questionnaire, the Child Behavior Checklist (CBCL) and the Psychosocial Stress Factors (PSF).ResultsHigh prevalence of problems was found for this sample: the CBCL showed 26.7% of clinical scores for Internalizing Problems, 40.6% for Externalizing Problems, and 40.6% for Total Problems. Exposure to family psychosocial stressors was also high, including severe disease (33%), physical aggression (28.9%), death (27.8%), psychiatric hospitalization (16.7%), suicide attempts (15.5%), and suicide (9.3%). Exposure to these family stressors was associated with an increase of two to four times in the prevalence of internalizing and externalizing problems.ConclusionsChildren exposed to substance abusers have more mental health problems than general population, even when compared to peers living in similar low-income areas. This is a group that should be target of a selective preventive intervention.  相似文献