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101.
Despite the widespread use of social media by students and its increased use by instructors, very little empirical evidence is available concerning the impact of social media use on student learning and engagement. This paper describes our semester‐long experimental study to determine if using Twitter – the microblogging and social networking platform most amenable to ongoing, public dialogue – for educationally relevant purposes can impact college student engagement and grades. A total of 125 students taking a first year seminar course for pre‐health professional majors participated in this study (70 in the experimental group and 55 in the control group). With the experimental group, Twitter was used for various types of academic and co‐curricular discussions. Engagement was quantified by using a 19‐item scale based on the National Survey of Student Engagement. To assess differences in engagement and grades, we used mixed effects analysis of variance (ANOVA) models, with class sections nested within treatment groups. We also conducted content analyses of samples of Twitter exchanges. The ANOVA results showed that the experimental group had a significantly greater increase in engagement than the control group, as well as higher semester grade point averages. Analyses of Twitter communications showed that students and faculty were both highly engaged in the learning process in ways that transcended traditional classroom activities. This study provides experimental evidence that Twitter can be used as an educational tool to help engage students and to mobilize faculty into a more active and participatory role.  相似文献   
102.
谢伟 《工业控制计算机》2011,24(4):16-17,20
近几年,各级政府开始要求城市供水企业将高层建筑二次供水纳入日常管理范围,为了达到科学高效的管理目标,提出采用计算机、网络和自控技术对二次供水泵站进行远程监控,并详细介绍了系统的建设目标、建设原则、网络结构、中心端硬软件配置、现场端数据采集和地址分配。该系统实现了不同型号设备跨平台的集成,在实践中具有推广价值。  相似文献   
103.
用VBA及ActiveX技术实现AutoCAD的二次开发   总被引:6,自引:0,他引:6  
论述了利用 Auto CAD内嵌的 VBA语言开发工具和 Active X技术 ,阐明了 Auto CAD进行二次开发的基本理论和方法。  相似文献   
104.
Abstract Recent upsurge in emphasis on larger class sizes and work‐based learning requires lecturers to be equipped to switch from traditional face‐to‐face teaching techniques to communicating with students using new technologies. Dialogue is the vital ingredient which underpins the successful learning experience, and staff in HE are facing a challenge in developing the necessary skills to make effective use of the emerging communication tools. These skills can only be acquired through practice, understanding of the pedagogy and awareness of the various options available. The aim of this paper is to explore, through presenting a case study, the potential benefits of cross‐institutional collaboration in information and communication technology staff development. Since both the University of Strathclyde and Glasgow Caledonian University were investigating ways of promoting good practice in the development and use of new learning technologies, it seemed prudent to combine forces and share ideas. The paper will examine how attempts were made to bridge the skills gap by enabling academic staff to experience Internet communication from the perspective of both student and teacher.  相似文献   
105.
Abstract Searching for information on the WWW involves locating a website and locating information on that site. A recent study implied that novice users' training needs exclusively relate to locating websites. The present case study tried to reveal the knowledge and skills that constitute these training needs. Fourteen pre‐university students, classified as novice (n = 7) or experienced WWW‐user (n = 7) performed three web search tasks. Their actions and verbalisations were recorded. Between‐group comparisons showed minimal performance differences. However, qualitative analyses of novice users' search performance suggest that their ability to locate websites could be enhanced by instructing monitoring skills and advanced system knowledge.  相似文献   
106.
A two-step method to optimize anisotropic composite panels with T-shaped stiffeners, including a new formulation of the transverse shear properties and an approximation of the ply contiguity (blocking) constraints as functions of the lamination parameters is provided. At the first step, a representative element of the stiffened panel (superstiffener) is optimized using mathematical programming and lamination parameters subjected to combined loading (in-plane and out-of-plane) under strength (laminate or ply failure), buckling and practical design constraints. Ply blocking constraints are imposed at this step to improve convergence towards practical laminates. At the second step, the actual superstiffener’s laminates are obtained by using a genetic algorithm. Results, for the case considered, show that the inclusion of transverse shear effects has an associated 2.5% mass penalty and that neglecting its effects might invoke earlier buckling failure. In addition, the influence of designing for failure strength at laminate or ply level is assessed.  相似文献   
107.
陈文智 《计算机应用研究》2001,18(3):109-110,130
介绍了一个能够在用户态下支持动态加载服务的应用系统,重点阐述了该系统的实现思想和方法。  相似文献   
108.
本文叙述了用PHI—550型给定的俄歇电子能谱(AES)研究了一种新的、性能优异的二次电子发射材料——MgO薄膜。薄膜由Ag—Mg合金经特殊高温激活工艺处理而成。以前人们对这种薄膜内部的各种元素的化学状态以及纵向原子浓度的分布状态一直不太清楚,本实验的成功证明了俄歇(Auger)电子能谱是研究这种薄膜的一种非常合适的实验方法。从实验结果中,我们发现如下几点 1.激活后,Mg和O原子的化学状态发生了显著的变化。 2.激活后,Mg、O和Ag原子的纵深分布也发生了显著的变化。 3.Mg原子氧化不充分,为了改进这一缺点,我们发明了一种新工艺。 4.使用新工艺激活,Mg原子可获充分氧化。  相似文献   
109.
气泡混合轻质土置换高速公路路堤工后沉降研究   总被引:2,自引:0,他引:2  
以申嘉湖杭高速公路(练杭段)堆载预压处理段路基沉降速率较大断面采用气泡混合轻质土置换高速公路路堤为例,采用土体弹塑性本构模型及Sjerrum等时e—lgp曲线理论,对置换后地基土体的应力路径变化进行理论分析,地基土处于超固结状态;通过现场实测沉降资料,置换前处理段沉降观测点月沉降量在14mm~18mm,置换后沉降观测点月沉降量在2nm~4mm,沉降速率收敛较快,处理后效果明显,能够有效减少工后沉降。结果表明,采用气泡混合轻质土置换高速公路路堤不仅施工方便,质量容易控制,而且处理效果显著,是一种有效的减少软土地基工后沉降的控制方法。  相似文献   
110.
针对漫滩洪水特性提出了改善黄河下游“二级悬河”的方案,应用动床模型试验对改善方案进行了模拟研究。结果显示:控制漫滩可以有效的减缓“二级悬河”的发展,加大主槽累计冲刷量,减小滩区淹没面积及改善河道横比降。如果黄河下游遭遇大漫滩洪水,可以在控制漫滩条件下排放最大洪峰流量不超过10 000 m3/s的过程洪水。  相似文献   
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