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1.
Evidence suggests that transient visual information, such as animations, may be more challenging to learn than static visualizations. However, when a procedural-manipulative task is involved, our evolved embodied cognition seems to reverse this transitory challenge. Hence, for object manipulative tasks, instructional animations may be more suitable than statics. We investigated this argument further by comparing animations with statics using a Lego task shown to university students, by examining three potential moderators of effectiveness: (a) the environment of manipulation (virtual or physical), (b) the quality of visual information (focused or unfocused), and (c) the presence of hands (no hands or with hands). In Experiment 1 we found an advantage of animation over statics, and no differences among the environments. In Experiment 2, we again observed an animation advantage, a small advantage of focused static information compared to unfocused static information, and a positive effect of not showing the hands.  相似文献   
2.
The effects of physical embodiment and physical presence were explored through a survey of 33 experimental works comparing how people interacted with physical robots and virtual agents. A qualitative assessment of the direction of quantitative effects demonstrated that robots were more persuasive and perceived more positively when physically present in a user׳s environment than when digitally-displayed on a screen either as a video feed of the same robot or as a virtual character analog; robots also led to better user performance when they were collocated as opposed to shown via video on a screen. However, participants did not respond differently to physical robots and virtual agents when both were displayed digitally on a screen – suggesting that physical presence, rather than physical embodiment, characterizes people׳s responses to social robots. Implications for understanding psychological response to physical and virtual agents and for methodological design are discussed.  相似文献   
3.
虚拟仪器(VI)将计算机采集测试分析引入到电子测量领域,用数字化和软件技术极大地提高了测量的灵活性。而VI远程测控系统是网络技术、通信技术一计算机虚拟技术结合的产物。远程控制技术能够使操作突破地域的限制,已在网络环境下PⅢ工控机上实现。  相似文献   
4.
以8031单片机为核心的泄漏电流测试仪的硬件结构和软件设计。  相似文献   
5.
梁辉 《铜业工程》2002,(4):69-71,76
提出VPN接入设备的体系结构 ,包括系统的应用模型、层次划分和内部详细结构 ,阐述实现VPN的关键技术。  相似文献   
6.
Collaborative work is an important part of tertiary education but it is very difficult to arrange and supervise for extremely large classes of students in their first year. The possibility that computer-mediated communication can be used to facilitate this type of learning is appealing from a pragmatic organisational point of view. This paper explains in detail what a ‘virtual team’ is in the educational context. It reports on an interpretive field study where students taking an introductory course were allowed to choose where and when they did the required collaborative work. The paper discusses the factors that should be taken into account when offering students the option of working as a virtual team. These include factors that influence the students’ choice. The project cannot be considered to have been successful but indicates reasons for the lack of success and suggests contexts in which it would be valuable to repeat the project. The importance of extensive preparation in terms of teaching the students necessary social and technological skills cannot be over emphasised.  相似文献   
7.
A new dynamic buffer allocation strategy based on the notion of marginal gains is presented for the buffer cache that is used by the operating system to store frequently accessed disk blocks in main memory, and the performance of the proposed strategy is compared with those of previous allocation strategies. In the proposed strategy, marginal gain values are predicted by exploiting functions that approximate the expected number of buffer hits per unit time. Experimental results from both trace-driven simulation and an actual implementation in the FreeBSD operating system show that the proposed strategy accurately predicts the marginal gain values for various workloads resulting in significantly improved buffer hit ratios.  相似文献   
8.
“一步建站”Web管理系统是指通过Web界面一次性提交用户资料,系统自动完成为上网建站用户开通虚拟服务器、进行域名解析、创建FTP维护账号及指定租用硬盘空间大小等一系列操作。同时,该系统还可对已开通的用户站点进行管理。  相似文献   
9.
面向大规模定制的虚拟设计研究   总被引:2,自引:0,他引:2  
综述了大规模定制的范围经济性和面向大规模定制的基本设计方法,并提出了一个虚拟设计框架,该框架改变了传统的设计模式,利用先进的设计方法学和仿真支撑技术为产品开发提供了最大柔性和敏捷性。同时,它提供了一个多学科合作的设计环境,用户直接参与进设计循环中。最后,结合新型剑杆织机的开发,展示了一个能够支持新产品快速成功开发的虚拟设计环境。  相似文献   
10.
本文介绍了纸尿裤生产线自动控制系统的硬件组成和应用软件。选用三菱运动控制器,设计出满足高精度相位、速度、位置、张力控制要求的自动化系统。  相似文献   
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