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981.
An important characteristic of virtual assembly is interaction.Traditional direct manipulation in virtual assembly relies on dynamic collision detection,which is very time-consuming and even impossible in desktop virtual assembly environment.Feature-matching is a critical process in harmonious virtual assembly,and is the premise of assembly constraint sensing.This paper puts forward an active object-based feature-matching perception mechanism and a feature-matching interactive computing process,both of which make the direct manipulation in virtual assembly break away from collision detection.They also help to enhance virtual environment understandability of user intention and promote interaction performance.Experimentl results show that this perception mechanism can ensure that users achieve real-time direct manipulation in desktop virtual environment. 相似文献
982.
Wai?Yu Email author Stephen?Brewster Email author 《Universal Access in the Information Society》2003,2(2):105-124
This paper introduces the development of a multimodal data visualisation system and its evaluations. This system is designed to improve blind and visually impaired peoples access to graphs and tables. Force feedback, synthesized speech and non-speech audio are utilised to present graphical data to blind people. Through the combination of haptic and audio representations, users can explore virtual graphs rendered by a computer. Various types of graphs and tables have been implemented, and a three-stage evaluation has been conducted. The experimental results have proven the usability of the system and the benefits of the multimodal approach. The paper presents the details of the development and experimental findings, as well as the changes of role of haptics in the evaluation. 相似文献
983.
984.
We have considered the role of charge-density-pseudogap for phonon-mediated super-conductivity on two-dimensional lattice. The propagators that enter generalized Eliashberg equations have been renormalized to account for quasi-particle energies related to the formation of the pseudogap, which has been assumed to be of d-wave symmetry. We have evaluated the superconducting transition temperature Tc as a function of doping. It occurs that Tc for d-wave symmetry well reflects experimental behavior. Our results for the isotope shift exponent show that at low doping, the presence of the pseudogap may contribute to > 1/2 as well as to > 1/2 values. 相似文献
985.
Podchernyaeva Irina A. Lavrenko Vladimir A. 《Powder Metallurgy and Metal Ceramics》2001,40(1-2):44-48
The formation of a surface layer on low-alloyed steel during light-thermal treatment with a composite material based on Si3N4 Al2O3 was investigated. The working surfaces were studied using metallographic, x-ray diffraction, and electron-probe microanalysis. It was found that the corrosion-resistant phases Al2SiO5, (Fe, Cr)2O3, (Cr, Al) 2O3, and NiCrO4 formed in the alloyed layer, increasing its microhardness by 2-5 times and its corrosion resistance in sea water by more than two orders of magnitude. 相似文献
986.
A fundamental objective of human–computer interaction research is to make systems more usable, more useful, and to provide users with experiences fitting their specific background knowledge and objectives. The challenge in an information-rich world is not only to make information available to people at any time, at any place, and in any form, but specifically to say the right thing at the right time in the right way. Designers of collaborative human–computer systems face the formidable task of writing software for millions of users (at design time) while making it work as if it were designed for each individual user (only known at use time). User modeling research has attempted to address these issues. In this article, I will first review the objectives, progress, and unfulfilled hopes that have occurred over the last ten years, and illustrate them with some interesting computational environments and their underlying conceptual frameworks. A special emphasis is given to high-functionality applications and the impact of user modeling to make them more usable, useful, and learnable. Finally, an assessment of the current state of the art followed by some future challenges is given. 相似文献
987.
孙茂松 《术语标准化与信息技术》2001,(3):19-23
本文扼要介绍了国家重点基础研究发展规划项目"973"项目中与语言信息处理领域相关的课题"面向大规模真实文本的汉语计算理论、方法和工具"的基本情况;讨论了该课题的主要研究目标、研究内容及具体实施方案;向读者显示了该课题的若干最新进展,并指出了标准(规范)问题在语言工程中的重要性. 相似文献
988.
城市精神反映了城市共同的理想目标、精神信念、文化底蕴、行为准则和生活方式的价值观念体系和群体意识,城市精神通过城市行为识别并表现出来。城市精神识别与政府行为、企业行为、公众行为、窗口行业行为、市民个体行为、行为环境改善、经济健康发展等城市行为具有互动性。城市精神的行为识别表现将促进城市形象的建设,增进城市个性繁荣与城市可持续发展,塑造完美的城市文化,延续历史文脉,促进社会文明。 相似文献
989.
Despite all the effort dedicated to bringing better User-Centered Design (UCD) tools to market, current studies show that the industry is still dominated by tools that do not support the activities and workstyles of designers. Also, there is a growing need for interaction design tools aimed at software engineers, a problem related to bringing usability into the software engineering processes.
We propose a new workstyle model that can be effectively used to envision, design and evaluate a new generation of innovative interaction and software design tools, aimed at integrating usability and software engineering.
We illustrate the effectiveness of our model by describing a new tool, called CanonSketch, that was built in order to support UCD in terms of the dimensions in our workstyle model. We also describe an evaluation study aimed at contrasting paper prototyping with our tool as well as the level of workstyle support. 相似文献
990.
The purpose of this paper is to propose and discuss a new method for information acquisition called collegial verbalisation. The method is explored in an empirical case study, and it consists of vehicle operators being videotaped while driving, followed by some of their colleagues making verbal reports while watching the video data. These colleagues have previously experienced exactly the same driving task as the operators, that is, they have travelled the same route, with the same craft, and used the same instrumentation. Thus, they are very familiar with the driving task and the driver environment. The empirical study is carried out on a high-speed ferry. The method is explored in relation to three rather open hypotheses: the amount of information provided in general; the reliability of the data; and how it contributes to the detection of 'buggy mental models' within the operators. The method is discussed in relation to the more traditional forms of verbal reports: concurrent and retrospective verbalisations, respectively. From the results of the empirical exploration, it is suggested that the method of collegial verbalisation may have combinatorial advantages that makes it more powerful as an analytical tool than the traditional forms of verbalisation, specifically if one wants to analyse work tasks that are dynamic and where the operators' behaviours are highly automated. However, more elaborate and systematic investigations must be conducted on the topic, and the paper therefore ends with a suggestion on an experimental design for this purpose. 相似文献