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Methods for the construction of DEMs of artificial slopes considering morphological features and semantic information

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Journal of Mountain Science 2022年第2期19卷 563-577页

作者： XU Yan ZHAO Ming-wei LU Jie WANG Chun JIANG Ling YANG Can-can HUANG Xiao-li Geographic Information and Tourism.College Chuzhou UniversityChuzhou 239000China State Key Laboratory of Resources and Environmental Information System Beijing 100101China College of Forestry Beijing Forestry UniversityBeijing 100083China

As human activities increase,artificially modified terrain is increasingly widely distributed in road,hydrological,and urban *** modified terrain plays an important role in protecting from geological disasters and in the planning and design of urban *** with natural slopes,artificial slopes have obvious morphological *** modeling methods are no longer suitable for digital elevation model(DEM)modeling of artificial slopes because they often seriously distort the DEM *** this paper,from the perspective of morphological characteristics,artificial slopes are divided into two types,namely,regular slopes and irregular slopes,based on whether the top and bottom lines of the artificial slope are ***,according to the morphological characteristics of the two types of slopes,the following DEM construction methods are designed:the first method(perpendicular+inverse distance weighted)is suitable for regular slopes,and the second method(perpendicular+high-accuracy surface modeling)is suitable for irregular ***,a DEM construction test is carried out using the artificial slopes in the study *** results show that for the regular and irregular slopes in the study area,the construction method proposed in this paper has significant advantages in morphological accuracy over the traditional method(triangulated irregular network),and the elevation accuracy method is also superior to the traditional method(using this method,the mean error and standard deviation error of the regular slope DEM are 0.08 m and 0.13 m,respectively,and those of the irregular slope DEM are 0.08 m and 0.06 m).In addition,the top lines and bottom lines can be included in the DEM construction of the background area after processing the elevation information of the boundary line to realize a smooth transition in the boundary between the artificial slope and the background area.

关键词： Artificial slopes DEM Morphological characteristics triangulated irregular network High-accuracy surface modeling

Terrain Simplification Research in Augmented Scene Modeling

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Journal of China University of Geosciences 2001年第4期12卷 351-355页

作者： Ming Delie You Kefei Tian Jinwen Liu Jian State Key Laboratory for Image Processing and Intelligent Control, Institute for Pattern Recognition and Artificial Intelligence , Huazhong University of Science and Technology , Wuhan 430074 Wang Guangju State Key Laboratory for Image Processing and Intelligent Control Institute for Pattern Recognition and Artificial Intelligence Huazhong University of Science and Technology Wuhan 430074 Faculty of Information Engineering China University of Geosciences Wuhan 430074

Augmented reality is the merging of synthetic sensory information into a user's perception of a real environment. As one of the most important tasks in augmented scene modeling, terrain simplification research has gained more and more attention. In this paper, we mainly focus on point selection problem in terrain simplification using triangulated irregular network. Based on the analysis and comparison of traditional importance measures for each input point, we put forward a new importance measure based on local entropy. The results demonstrate that the local entropy criterion has a better performance than any traditional methods. In addition, it can effectively conquer the 'short-sight' problem associated with the traditional methods.

关键词： augmented reality scene modeling terrain simplification triangulated irregular network importance measures local entropy.

Large-Scale Terrain Simplification and Visualization Based on TIN

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Computer Aided Drafting,Design and Manufacturing 2008年第2期18卷 1-8页

作者： KANG Lai, WU Ling-da, YANG Bing, SONG Han-chen (College of Information Systems & Management, National University of Defense Technology, Changsha 410073, China)

In the preprocessing phase, the global terrain model is partitioned into blocks with their feature points being picked out to generate TIN model for each terrain block, then the multi-resolution models of terrain organized in the form of quad-tree is created bottom-up. Cracks between terrain blocks are avoided by inserting vertices to form common boundaries. At run-time, a view-dependent LOD algorithm is used to control the loading and unloading of the proper blocks by an additional synchronous thread. To eliminate the artifacts created by LOD transitions, geomorphing is used in real-time. These rendering strategies increase the throughput of GPU and avoid imbalance of load among CPU, GPU and Disk I/O. Experimental results show that the system can perform visually smooth rendering of large-scale terrain scenes with fine quality at an average rate of 80 fps.

关键词： real-time rendering 3D terrain multi-resolution triangulated irregular network quad-tree