U.S.-Italy Cooperative Research: Visibility Characteristicsof Digital Terrain Models

该奖项将使伦斯勒理工学院的乔治纳吉教授 意大利国家研究所的Bianca Falcidieno博士 意大利热那亚的理事会，继续成功合作， 始于1981年。 在前一阶段开发的算法 研究用于定义一种数据结构，称为可见性图， 一个适当的三角地形模型。 地图显示 任何两点之间是否有一条畅通的视线。 该算法与现有的隐藏面算法有关， 结合了基于其独特特性的概念， 问题. 此外，可见性模型的全局性质 提供了一个有用的替代偏导数定义 地形实体 已经开发了其他算法， 所得到的可见性图，以排列最佳观测值 点 在调查人员要考虑的问题中， 是：视线（电视，调频，雷达）通信和 监视问题;隐藏路径;定位导航; 从可见性地图到原始地形的逆变换 数据;数据压缩;重要地形的提取 如山脊和山谷的特征。 美国PI将带来与计算机的合作经验 图像的视觉、光学扫描和工程应用 识别，遥感，地理数据处理， 计算几何 意大利方面将提供专业知识， 计算地理学，计算机制图学，计算机图形学， 实体建模和图论。 这项研究预计将 对计算几何学和地形信息 系统和电信。

This award will enable Prof. George Nagy of Rensselaer Polytechnic Institute and Dr. Bianca Falcidieno of the Italian National Research Council in Genova, Italy, to continue a successful collaboration that started in 1981. An algorithm developed in the previous stage of the research is used to define a data structure, called a visibility map, on an appropriately triangulated terrain model. The map shows whether there is an unimpeded line of sight between any two points. The algorithm is related to existing hidden-surface algorithms, but incorporates concepts based on the unique characteristics of the problem. Additionally, the global nature of the visibility model provides a useful alternative to partial derivatives for defining topographic entities. Other algorithms have been developed applying the resulting visibility map to rank order the best observation points. Among the problems to be considered by the investigators are: line of sight (television, FM, radar) communications and surveillance problems; hidden paths; orientation and navigation; the inverse transform from the visibility map to the original terrain data; data compression; and the extraction of significant terrain features such as ridges and valleys. The U.S. PI will bring to the collaboration experience with computer vision, optical scanning, and engineering applications of pattern recognition, remote sensing, geographic data processing, and computational geometry. The Italian side will provide expertise in computational geography, computer cartography, computer graphics, solid modeling, and graph theory. The research is expected to contribute to computational geometry, to topographic information systems, and to telecommunications.