Charge It! Translating Electric Vehicle Research Results to Engage 7th and 8th Grade Girls

Journal of Science Education and Technology - Despite attempts to generate interest in science and technology careers, US students continue to show reduced interest in science, technology,...     

新形势下高校奖学助学的标准及其实施研究

我国高校资助政策体系应从无偿资助为主向有偿资助、奖励资助转变。扩大有偿资助比例和范围,加大奖学金资助力度,减少无偿资助。既要发挥资助体系的扶贫解困功能,还要发挥其教育功能。     

FACR：一种快速且准确的车辆识别器

现存的细粒度车辆识别器在多个数据集上取得了良好的性能。但这些方法通常运行效率低;而且当图像中存在多辆车时,易受背景干扰,不能准确地定位注意力区域。提出一种快速且准确的车辆识别器FACR,与现存方法相比有如下3个特点：1)其注意力区域定位组件,对图像中背景车辆有很高的鲁棒性;2)网络结构相对简单,在保持准确度相当的情况下,计算效率更高;3)首次使用层次分类的方法对车辆进行细粒度分类,使得单一网络能同时用于识别汽车类型、生产商、汽车型号和生产年份。在Compcars和Stanford Cars标准数据集上进行实验。结果表明,与现存方法相比,FACR在计算效率和分类精度方面具有良好性能。     

Editorial: Single-blind or double-blind review processes?

Educational Studies in Mathematics - The investigation at scale of the tensions that teachers need to manage when deciding to follow recommendations for practice has been hampered by the problem of...     

Do more hours in center-based care cause more externalizing problems? A cross-national replication study

Whether high quantities of center-based care cause behavior problems is a controversial question. Studies using covariate adjustment for selection factors have detected relations between center care and behavior problems, but studies with stronger internal validity less often find such evidence. We examined whether within-child changes in hours in center-based care predicted changes in externalizing problems in toddlers and preschoolers (N = 10,105; 49% female; data collection 1993–2012) in seven studies, including from Germany, Netherlands, Norway, two from Canada and two from the U.S. Race/ethnicity data were only collected in the United States (57% and 80% White; 42% and 13% African-American; 1.2% and 5% Latinx). Meta-analyses showed no association (r = .00, p = .88) between hours in center-based care and externalizing problems.     

The future is present in the past: A meta-analysis on the longitudinal associations of parent–adolescent relationships with peer and romantic relationships

Positive peer and romantic relationships are crucial for adolescents' positive adjustment and relationships with parents lay the foundation for these relationships. This longitudinal meta-analysis examined how parent–adolescent relationships continue into later peer and romantic relationships. Included longitudinal studies (k = 54 involving peer relationships, k = 38 involving romantic relationships) contained demographically diverse samples from predominantly Western cultural contexts. Multilevel meta-regressions indicated that supportive and negative parent–adolescent relationships were associated with supportive and negative future peer and romantic relationships. Meta-analytic structural equation modeling (k = 54) indicated that supportive parent–adolescent relationships unidirectionally predicted supportive and negative peer relationships, while negative parent–adolescent relationships were bidirectionally associated with supportive and negative peer relationships. Maintaining mutually supportive relationships with parents may help adolescents to develop positive social relationships.     

吸附气体小分子石墨烯的紫外光谱的第一性原理研究

为研究吸附气体小分子的石墨烯紫外光谱,可以能够灵敏准确的测量出石墨烯吸附的气体小分子的种类。本文采用杂化密度泛函B3LYP方法在6-31G*的基组上优化了吸附CO,H2O,CH4气体分子的石墨烯的稳定结构。采用杂化密度泛函B3LYP方法在6-31+G*的基组上计算了吸附CO,H2O,CH4气体分子的石墨烯的稳定状态下的电子结构。基于Gelius模型,算出其紫外光谱。这为通过光学手段研究和制备高灵敏度的气体小分子探测器探索了一条新的道路。     

Consensus for multiple heterogeneous Euler–Lagrange systems with time-delay and jointly connected topologies

In this paper, we consider the consensus problem of multiple agents modeled by Euler–Lagrange (EL) equation, among which two classes of agents are addressed, i.e., some agents with exactly known parameters and the others with parametric uncertainties. We propose a distributed consensus protocol for the heterogeneous EL systems in which both time-delay and jointly connected topologies are taken into consideration. Based on graph theory, Lyapunov theory and Barbalat?s lemma, the stability of the controller is proved. A distinctive feature of this work is to investigate the consensus problem of EL systems with heterogeneous dynamics, time-delay and jointly connected topologies in a unified theoretical framework. Simulation results are also provided to illustrate the effectiveness of the obtained results.     

Mean-square exponential stability for a class of discrete-time nonlinear singular Markovian jump systems with time-varying delay

This paper investigates the problem of mean-square exponential stability for a class of discrete-time nonlinear singular Markovian jump systems with time-varying delay. The considered systems are with mode-dependent singular matrices _Er(k)$E_{r\left(k\right)}$. By using the free-weighting matrix method and the Lyapunov functional method, delay-dependent sufficient conditions which guarantee the considered systems to be mean-square exponentially stable are presented. Finally, some numerical examples are employed to demonstrate the effectiveness of the proposed methods.     

竞技运动视频识别与比较系统的研究

竞技运动视频的识别与比较系统是现代科技训练方法在竞技运动训练中的实现。以定点拍摄的跳远运动视频为研究对象,实现了视频中运动目标分割和提取,进行对运动目标进行合成比较。通过对运动员实际训练体态或动作与标准体态或动作的比较,达到科学的运动分析与诊断的目的。这些功能的实现都是借助于VC++平台在WidowsXP系统下研究和实现的,系统便携、操作简单,有现场实效性。