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排序方式: 共有1691条查询结果,搜索用时 78 毫秒
91.
James E. Corter Sven K. Esche Constantin Chassapis Jing Ma Jeffrey V. Nickerson 《Computers & Education》2011
A large-scale, multi-year, randomized study compared learning activities and outcomes for hands-on, remotely-operated, and simulation-based educational laboratories in an undergraduate engineering course. Students (N = 458) worked in small-group lab teams to perform two experiments involving stress on a cantilever beam. Each team conducted the experiments in one of three lab formats (hands-on, remotely-operated, or simulation-based), collecting data either individually or as a team. Lab format and data-collection mode showed an interaction, such that for the hands-on lab format learning outcomes were higher when the lab team collected data sets working as a group rather than individually collecting data sets to be combined later, while for remotely-operated labs individual data collection was best. The pattern of time spent on various lab-related activities suggests that working with real instead of simulated data may induce higher levels of motivation. The results also suggest that learning with computer-mediated technologies can be improved by careful design and coordination of group and individual activities. 相似文献
92.
为更好地将移动自组网络用于网络控制系统(NCS),结合NCS的网络特性,提出了一种基于链路信号质量的QoS路由算法。主要QoS机制包括根据接收信号强度选择较稳定的路由;用Hello报文广播节点的预留带宽;中间节点为所有受影响的数据流修复路由、目的节点向源节点广播路由修复报文进行路由修复。NS2仿真表明当节点移动性强时,该QoS路由算法可有效减少网络的平均端到端时延和丢包率,提高控制系统稳定性。 相似文献
93.
陈木朝 《电脑编程技巧与维护》2011,(8):96-97
介绍了一种基于Ajax和FMS的视频直播学习系统。该系统采用B/S结构,应用支持异步请求的Ajax技术提供即时通信,利用基于RTMP协议的FMS提供流媒体服务。由于客户端只需要一个支持Flash的网页浏览器,并且具有占用带宽少、响应及时、视频质量高和容易部署等特点,该系统在远程教育等领域具有较大的应用前景。 相似文献
94.
This paper proposes a web-based interactive speaking improvement system for EFL learners. Using fuzzy matching, the system automatically compares the learner’s and the system’s pronunciation and immediately provides corrective interaction whereby the student can improve speaking via continuous imitation and practice at the computer. The system, having been tested on Taiwanese students who needed to achieve a speaking proficiency equivalent to CEF Level A2, is found to be highly effective for the intended purpose. 相似文献
95.
在Ad Hoc网络中,如何基于多信道有效地利用网络中的频谱资源,提高网络的性能,已经成为近几年来研究的热点。在DSDV路由协议的基础上,提出了一种基于减少网络中的信道切换的路由算法——OLCH-DSDV,该算法采用最小切换时延的信道分配策略,尽量减少信道切换产生的时延,从而降低了网络时延,提高了吞吐量。该算法要求源节点通过自身维护的路由和信道使用信息,选择到达目的节点的最优路径,也就是需要最少信道切换的路径。仿真结果表明该路由改进算法在有效提高系统吞吐量的同时,也有效地减少了网络中的传输时延。 相似文献
96.
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98.
Nikolaos Vernadakis Panagiotis AntoniouMaria Giannousi Eleni ZetouEfthimis Kioumourtzoglou 《Computers & Education》2011
The purpose of this study was to determine the effectiveness of a hybrid learning approach to deliver a computer science course concerning the Microsoft office PowerPoint 2003 program in comparison to delivering the same course content in the form of traditional lectures. A hundred and seventy-two first year university students were randomly assigned into two teaching method groups: traditional lecture instruction (TLI) and hybrid lecture instruction (HLI). Each group received six 95-min periods of instruction divided into 4 sections: a) 5-min brief outline of the key learning points, b) 40-min lecture on general knowledge c) 45-min constructivist-inspired learning activities and d) 5-min summary on key learning points. In the beginning and the end of this study students completed a 17-item multiple choice knowledge test. Two-way analysis of variances (ANOVA), with repeated measures on the last factor, were conducted to determine effect of method groups (TLI, HLI) and measures (pre-test, post-test) on knowledge test. The measures main effect was significant, as well as the groups x measures interaction effect. Two independent-samples t test were conducted to follow up the significant interaction. Differences in mean ratings of knowledge performance between the two teaching groups were not significantly different at first measure, while the TLI method group yielded a significantly lower mean rating at second measure. The findings indicated that HLI approach might be a superior option for undergraduate students on learning the Microsoft office PowerPoint 2003 program. 相似文献
99.
Pedro Almenar 《Computers & Mathematics with Applications》2012,63(1):310-317
This paper presents an upper bound for the distance between a zero and a critical point of a solution of the second order linear differential equation (p(x)y′)′+q(x)y(x)=0, with p(x),q(x)>0. It also compares it with previous results. 相似文献
100.
教育客户服务中心结构设计 总被引:1,自引:0,他引:1
教育客户服务中心系统是以提高教育服务质量和效率为目标,研究相关的信息描述、定义、存储、检索、交换、分析和挖掘技术,综合构成教育客户服务中心的前台接入和后台处理的最新技术,通过与教学服务管理系统和教学行为分析和质量评估系统集成,为高校的招生、教务管理等教育服务管理工作提供高效的辅助手段,促进教育资源的信息规范化。 相似文献