The Effect of High School Socioeconomic Status on the Predictive Validity of SAT Scores and High School Grade‐Point Average

Research has often found that, when high school grades and SAT scores are used to predict first‐year college grade‐point average (FGPA) via regression analysis, African‐American and Latino students, are, on average, predicted to earn higher FGPAs than they actually do. Under various plausible models, this phenomenon can be explained in terms of the unreliability of predictor variables. Attributing overprediction to measurement error, however, is not fully satisfactory: Might the measurement errors in the predictor variables be systematic in part, and could they be reduced? The research hypothesis in the current study was that the overprediction of Latino and African‐American performance occurs, at least in part, because these students are more likely than White students to attend high schools with fewer resources. The study provided some support for this hypothesis and showed that the prediction of college grades can be improved using information about high school socioeconomic status. An interesting peripheral finding was that grades provided by students’ high schools were stronger predictors of FGPA than were students’ self‐reported high school grades. Correlations between the two types of high school grades (computed for each of 18 colleges) ranged from .59 to .85.     

高职“变频器系统运行与维护”课程分层小班教学实践与探索

实施分层小班教学,能提高教学的针对性和有效性,可有效激发学生学习的积极性和主动性,提高技能培养效果。该文以淮安信息职业技术学院"变频器系统运行与维护"课程的教学改革为例,探讨实施分层小班教学的意义和实施方法。     

Quasi-static mechanical behaviour of soils used for natural turf sports surfaces and stud force prediction

The quasi-static testing of soils used in natural turf pitches yields key parameters in soil modelling, including elastic moduli, Poisson’s ratio and Mohr–Coulomb parameters for shearing resistance and cohesion in soil. The bulk strength of a Sand soil used in the construction of elite sports surfaces was found to increase initially and then decrease with increasing water content due to apparent cohesion effects. For a Clay Loam soil, more common in recreational facilities, shear strength decreased with water content. Reducing density resulted in a reduction of shear strength and elastic moduli in both soils due to reduced packing of particles reducing particle–particle contact surface area. The effect of roots on the shear strength of a Sand soil was not significant but reduced elastic moduli significantly. Horizontal forces measured during running and turning in a biomechanics laboratory were in good agreement with forces predicted using a simple quasi-static soil model for coarse-grained (Sand) soils although this was not the case with the Clay Loam soil.     

我国优秀女子跳高运动员专项身体素质指标体系及评价标准 研究

运用特尔菲法、问卷调查法、格拉布斯法、因子分析以及回归分析等方法,对我国优秀女子跳高运动员专项身体素质进行研究.研究结果:(1)建立我国优秀女子跳高运动员专项身体素质指标体系;(2)建立关于专项身体素质的专项成绩预测模型;(3)研制包括专项身体素质典型指标的评价标准和评价方法,专项身体素质综合发展水平、专项身体素质发展均衡程度、专项身体素质综合发展水平与专项成绩相适应程度一系列评价标准和评价方法.     

Design of rules for in-flight non-parametric tuning of PID controllers for unmanned aerial vehicles

Designing high performance controllers for multirotors is a rigorous task that is often solved by trial and error approach. Trial and error tuning usually results in non-optimal controller parameters. Tuning controllers based on the existing quadrotor models would result in poor performance of quadrotors due to simplifications and inaccuracies in the underlying models. In this paper optimal tuning rules for quadrotor attitude dynamics are designed, which guarantees near-optimal performance and robustness. A single in-flight run of the Modified Relay Feedback Test that takes only few seconds with guaranteed stability is enough to have near-optimal tuning of the controller. The designed tuning rule is tested experimentally in-flight on a custom-built quadrotor. The results showed significant advantages in performance and robustness due to the proposed approach.     

VLAN技术在图书馆网络中的应用

作为一门新兴网络技术，VLAN极大地减轻了网络管理者的负担，正逐渐成为网络设计的首选方案。本文介绍了VLAN的定义、特点、划分方式以及在图书馆网络中的实际应用。     

The research and evaluation of serious games: Toward a comprehensive methodology

The authors present the methodological background to and underlying research design of an ongoing research project on the scientific evaluation of serious games and/or computer‐based simulation games (SGs) for advanced learning. The main research questions are: (1) what are the requirements and design principles for a comprehensive social scientific methodology for the evaluation of SGs?; (2) to what extent do SGs contribute to advanced learning?; (3) what factors contribute to or determine this learning?; and (4) to what extent and under what conditions can SG‐based learning be transferred to the real world? In the Netherlands between 2005 and 2012, several hundred SG sessions with 12 SGs were evaluated systematically, uniformly and quantitatively to create a dataset, which comprises data on 2488 respondents in higher education or work organizations. The authors present the research model, the quasi‐experimental design and the evaluation instruments. This focus in this paper is on the methodology and dataset, which form a sound foundation for forthcoming publications on the empirical results.     

创新性学习环境的构建:现代教学技术与课程整合的角度

创新性学习是人的本质及时代的要求。开展创新性学习要求创设相适应的创新性学习环境。创新性学习环境蕴含知识的泛在、探索的真实以及生成的自由等基本特征,需要课程元素与技术元素的同时加入才能达到涵养创新性学习的目的。因此,可以从现代教学技术与课程整合的角度,来建构创新性学习环境。