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41.
为了满足机载显示器图形生成系统的小尺寸、低功耗需求,提出了一种基于龙芯2K1000的全国产图形生成与处理方案。该方案以2K1000为核心构建硬件平台,使用2K1000内部集成的中央处理器、图形处理器、显示控制器,以及外部的内存实现图形的计算生成和双缓存显示,配合国产可编程逻辑器件实现图形与外视频的叠加显示及机载通信总线扩展。软件上采用航空专用的国产天脉操作系统,基于天脉操作系统设计了关键的图形显示驱动、帧存驱动、显示控制器驱动。实验结果表明,在输出1 024 pixel×768 pixel分辨率显示时,典型机载图形画面帧率达到35 frame/s,整体功耗约10 W。该方案扩展性强、功耗低,满足实时显示需求,在机载显示器领域有着广泛的应用空间。 相似文献
42.
Monday Eze Charles Okunbor Deborah Aleburu Olubukola Adekola Ibrahim Ramon Nneka Richard-Nnabu Oghenetega Avwokuruaye Abisola Olayiwola Rume Yoro Esomu Solomon 《计算机系统科学与工程》2022,41(2):595-609
This work demonstrates in practical terms the evolutionary concepts and computational applications of Parametric Curves. Specific cases were drawn from higher order parametric Bezier curves of degrees 2 and above. Bezier curves find real life applications in diverse areas of Engineering and Computer Science, such as computer graphics, robotics, animations, virtual reality, among others. Some of the evolutionary issues explored in this work are in the areas of parametric equations derivations, proof of related theorems, first and second order calculus related computations, among others. A Practical case is demonstrated using a graphical design, physical hand sketching, and programmatic implementation of two opposite-faced handless cups, all evolved using quadratic Bezier curves. The actual drawing was realized using web graphics canvas programming based on HTML 5 and JavaScript. This work will no doubt find relevance in computational researches in the areas of graphics, web programming, automated theorem proofs, robotic motions, among others. 相似文献
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44.
We propose an architecture for multi-user augmented reality with applications in visualisation, presentation and education, which we call Studierstube. Our system presents three-dimensional stereoscopic graphics simultaneously to a group of users wearing light weight see-through head mounted displays. The displays do not affect natural communication and interaction, making working together very effective. Users see the same spatially aligned model, but can independently control their viewpoint and different layers of the data to be displayed. The setup serves computer supported cooperative work and enhances cooperation of visualisation experts. This paper presents the client-server software architecture underlying this system and details that must be addressed to create a high-quality augmented reality setup. 相似文献
45.
When students use computers as learning tools, the whole process of learning, and, indeed, the learners themselves, are transformed. This article illustrates some techniques that foster transformative learning in computer-assisted first-year literature classes: first, a lesson plan on A Valediction: Forbidding Mourning that uses Microsoft Word functions, including format painter, tables, and annotation to explore meaning in context; second, a plan for learners to use subconference options in the Daedalus Interactive Writing Environment to analyze Oedipus Rex; finally, a demonstration of how students engage in a meta-reflection process as they explore Barn Burning with Freelance Graphics.Marguerite Jamieson is an English instructor at Anne Arundel Community College in Arnold, Maryland, and a doctoral student at George Mason University. Her research interests include forming bridges between adult learning theory and contemporary literary theory — especially drawing on transformational learning theory and the work of Mikhail Bakhtin and Lev Vygotsky.Rebecca Kajs holds a doctorate in English from Texas Woman's University with a concentration in rhetoric. For ten years, she taught the use of heuristic tools for reading analysis at the University of Texas at Arlington. She is currently an associate professor of English and Philosophy at Anne Arundel Community College.Anne Agee holds a doctorate in rhetoric from The Catholic University of America. A professor of English and formerly director of the Humanities Computer Center at Anne Arundel Community College, she is currently the college's Coordinator of Instructional Technology. Dr. Agee and Professor Jamieson have collaborated in a study of the learning environment in a computer classroom, the results of which were published in the Fall 1995 issue of Teaching/Learning Conversations. Dr. Agee has also published Using [Daedalus] InterChange as a Teachers' Journal in the Fall 1995 issue of Wings. 相似文献
46.
罗枫 《艺术与设计.数码设计》2011,(3)
文章分别从彩陶发生以及纹样的演变、装饰图形的抽象化和原始装饰图形意蕴的象征性三个方面来阐述原始思维在原始装饰图形形式上的体现,指出原始人类的装饰图形创造过程本身就是一个思维认识的过程,这个过程是在不断的时间和认识的反复循环中发展和丰富起来的。 相似文献
47.
介绍了TW8811的基本结构和特性,论述实现位图OSD的基本原理,给出了基于TW8811的车载DVD音影系统图形化用户界面的设计方案,并讨论关键元器件的选取及使用注意事项.该设计方案实现的车载音影系统操作界面友好、灵活性强,只需修改相应的图形库即可应用于需要视频图形叠加的其他领域. 相似文献
48.
Ajax技术给传统的爬虫带来了巨大的挑战,为了能够提取出在Ajax程序中隐藏的WEB资源,需要解决两大关键问题:JavaScript脚本解析和每一次脚本事件触发后的页面状态信息的保存。提出一种适合Ajax的爬虫模型,在模型中设计了一个嵌入的脚本解析引擎和使用了有向状态图,有效地解决了上述的两个关键问题。实验结果显示该爬虫模型能够有效地提取出Ajax程序中的隐藏资源。 相似文献
49.
为解决服务配置组合过程中服务知识的重用问题,建立服务知识重用策略及其表示方法.采用了形式化定义的方法对孤立服务知识进行建模,析取常见的服务知识重用模式与策略,提出利用拓扑模型的方式对服务知识的重用策略进行描述,构建基本的服务重用拓扑模型结构.实验分析结果表明,该方法使复杂的服务知识组件关系变得清晰、完整,解决以往的建模方法中信息描述不完全的问题. 相似文献
50.
Higher‐order finite element methods have emerged as an important discretization scheme for simulation. They are increasingly used in contemporary numerical solvers, generating a new class of data that must be analyzed by scientists and engineers. Currently available visualization tools for this type of data are either batch oriented or limited to certain cell types and polynomial degrees. Other approaches approximate higher‐order data by resampling resulting in trade‐offs in interactivity and quality. To overcome these limitations, we have developed a distributed visualization system which allows for interactive exploration of non‐conforming unstructured grids, resulting from space‐time discontinuous Galerkin simulations, in which each cell has its own higher‐order polynomial solution. Our system employs GPU‐based raycasting for direct volume rendering of complex grids which feature non‐convex, curvilinear cells with varying polynomial degree. Frequency‐based adaptive sampling accounts for the high variations along rays. For distribution across a GPU cluster, the initial object‐space partitioning is determined by cell characteristics like the polynomial degree and is adapted at runtime by a load balancing mechanism. The performance and utility of our system is evaluated for different aeroacoustic simulations involving the propagation of shock fronts. 相似文献