Length-based vehicle classification in multi-lane traffic flow

For the realtime classification of moving vehicles in the multi-lane traffic video sequences, a length-based method is proposed. To extract the moving regions of interest, the difference image between the updated background and current frame is obtained by using background subtraction, and then an edge-based shadow removal algorithm is implemented. Moreover, a thresholding segmentation method for the region detection of moving vehicle based on location search is developed. At the estimation stage, a registration line is set up in the detection area, then the vehicle length is estimated with the horizontal projection technique as soon as the vehicle leaves the registration line. Lastly, the vehicle is classified according to its length and the classification threshold. The proposed method is different from traditional methods that require complex camera calibrations. It calculates the pixel-based vehicle length by using uncalibrated traffic video sequences at lower computational cost. Furthermore, only one registration line is set up, which has high flexibility. Experimental results of three traffic video sequences show that the classification accuracies for the large and small vehicles are 97.1% and 96.7% respectively, which demonstrates the effectiveness of the proposed method.     

光学系统成像的仿真研究

利用波动光学的基本理论,对复杂的光学系统的成像进行分析,并结合MATLAB语言的编程和图像处理功能。通过数值模拟形象地把光学系统成像的结果显示出来。结果表明,在对单透镜系统成像分析的基础上,可以对各种复杂的光学系统的成像进行分析。利用这种方法作为辅助教学手段,有助于学生更加深刻地理解光学系统的成像,提高教学质量。     

The reality of virtual worlds: pros and cons of their application to foreign language teaching

This article presents our experience of testing the OpenSim platform as a tool in teaching French to 108 tourism students at Universidad Rey Juan Carlos (Madrid, Spain). The article begins with some theoretical reflections on the behaviour of the student when using a virtual platform by means of an avatar, and with our observations of how this doubling of identity is actually the greatest asset of virtual worlds when we intend to apply them to teaching (1. Introduction). Then we move on to present our goals and method of work (2. Aims and methodology) and to analyse the development of the virtual space or sim, setting out the teaching strategies that were employed in each of the islands we created, and which correspond to reading comprehension, listening comprehension and written expression (3. Metaverse design). In order to assess the language learning results, we also devised tests throughout the experiment, which were repeated one month later. The assessment shows that the process of language acquisition is positive (4. Results analysis). Finally, we demonstrate that the rise of virtual worlds has been backed up by psycholinguistic factors, but at the same time their applicability and sustainability depend on technical aspects and very especially on theoretical and pedagogical tenets which are still to be drawn up (5. Conclusions).     

把“红色虚拟旅游”引入到高校纲要课教学中

课堂教学是高校思想政治教育的主渠道。充分利用现代新媒体,通过跟随课本红色虚拟旅游,开展“重上井冈山”、“重走长征路”、“回延安”、“沂蒙颂”等红色旅游系列活动,增强大学生的课堂参与度,从而提高教学实效,传播精神正能量,实现引导大学生认可接受并主动践行社会主义核心价值观的目的。以《重走长征路》为例,对红色虚拟旅游教学改革的基本原则、实施方案、心得体会进行总结。     

基于VRP的中小学虚拟科技馆的设计和实现

中小学虚拟科技馆作为建设数字化校园的一部分,可以使学生在虚拟科技馆中自由浏览,体验或操控虚拟展示的科学技术和产品,弥补实体科技馆的局限,培养学生的科学精神和素养。文章阐述了建设中小学三维立体虚拟科技馆的步骤、虚拟科技馆的数据采集与教学设计、虚拟科技馆建筑与展品的建模与烘培方法以及利用VR-Platform构建虚拟场景、实现虚拟交互控制的方法。     

影响教育虚拟社区中学习动机激发因素的实证分析

教育虚拟社区中的学习动机是学习者通过自我调节,使自身的内在要求与学习行为的外在诱因相协调,引起和维持学习者在教育虚拟社区中的学习活动,并激励、指引学习者的行为朝向一定学习目标的内部心理状态。在基于课程＂学习科学与技术＂的教育虚拟社区学习实践的基础上,实证分析了教育虚拟社区中学习动机激发的影响因素,通过描述性统计、回归分析、因子分析和聚类分析发现：教师因素、学习者因素、环境因素和文化因素是影响学习者在教育虚拟社区中学习动机激发的四大要素,学习者在教育虚拟社区中学习动机的激发有赖于以上各因素协同作用的发挥,由此提出了影响教育虚拟社区学习动机激发因素的分析模型。     

基于XEN云平台的网络安全实验教学

网络安全实验课程中要求学生进行一些比较复杂的实验,实验环境的搭建往往涉及到多台主机,并且这些主机需要按照实验规范组成一个特定的拓扑结构。对于学生而言,在构建实验环境时会受到个人设备硬件条件的限制,为了满足多人同时进行网络安全实验的需求,我们设计并实现了一种基于XEN开源软件的网络安全实验云平台,向学生提供虚拟网络实验环境。本文着重介绍了基于XEN的实验云平台的体系架构,分析了如何在云平台上快速构建复杂的虚拟网络,以进行网络安全实验教学。最后,我们通过一个防火墙实验的实例来说明该云平台的使用和有效性。通过在学生中进行教学实践表明,基于XEN的网络安全实验云平台大大简化了实验环境的构建,减少了实验硬件投资,可以很好地容纳多人同时进行实验。     

基于UDK引擎的图书馆虚拟漫游系统的设计与实现

在信息数字化、可视化、虚拟化的演变进程中,虚拟现实技术为数字图书馆的发展和演变开阔了全新的视野.文章分析了虚拟现实技术在图书馆应用的国内外现状,界定了虚拟现实图书馆的概念并阐述了其特点与优势.在此基础上,以图书馆虚拟漫游系统为例,介绍了使用UDK（Unreal Development Kit）引擎和3ds max开发虚拟图书馆漫游系统的过程和技术问题,提出了一套开发高真实、高交互的3D虚拟图书馆漫游系统的可行方案.     

面向成人教育开放式虚拟实验平台的设计与应用

实践教学是成人教育的一块短板,现有的实践教学资源也较为零散、单一。文章针对这些结构差异、开发语言不同,甚至数据库管理系统也各异的课程实验系统,提出了一种采用面向服务架构(SOA)技术,将这些孤立的异构系统集成到统一的实验管理平台中,实现一个松耦合、标准化的开放式虚拟实验平台。各类课程实验项目具备统一的操作模式和管理方式,便于成人学生通过网络进行虚拟仿真实验。