First Paragraph Cadastral systems are traditionally two-dimensional. However, there is now much talk of extending them into the third dimension, in part by incorporating the elevation information in a terrain model. Terrain models have been around for quite some time and so have the arguments between using a grid (or DEM-Digital Elevation Model, in American parlance), or a triangulation (TIN-Tr...

The geometry clipmap introduced in Losasso and Hoppe 2004 is a new level-of-detail structure for rendering terrains. It caches terrain geometry in a set of nested regular grids, which are incrementally shifted as the viewer moves. The grid structure provides a number of benefits over previous irregular-mesh techniques: simplicity of data structures, smooth visual transitions, steady rendering r...

Although it is clear that walking over different irregular terrain is associated with altered biomechanics, there is little understanding of how we quickly adapt to unexpected variations in terrain. This study aims to investigate which adaptive strategies humans adopt when performing an unanticipated step on an irregular surface, specifically a small bump. Nine healthy male participants walked ...

Segmentation is a rst step towards successful tracking and object recognition in 2-D pictures. Mostly the pictures are segmented with respect to quantities as range, intensity etc. Here a method is presented for segmentation of 2-D laser range pictures with respect to both range and variance simultaneously. This is very useful since man-made objects diier from the background in the terrain by t...

We present a technique for representing bounded-degree planar graphs succinctly while permitting I/O-efficient path traversal. To represent a graph G on N vertices, each with an associated key of q = O(lgN) bits, we use Nq +O(N) + o(Nq) bits. Using this representation, a path of length K can be traversed with O(K/ lgB) I/Os, where B is the disk block size. Our structure may be adapted to repres...

Although hydraulic erosion modeling on a GIS terrain models has been addressed by a body of previous work, it still remains an open problem. In GIS, raster representation and triangular irregular networks (TIN) are the most commonly used surface models, because they are simple and offer implicit topological information. However, these data structures do not allow the simulation of erosion on co...

Selection of a set of significant points from a raster digital terrain model is important for constructing a triangular irregular network. The set of points should contain information of terrain surface as rich as possible. INTRODUCTION The most common form of digital terrain model is the raster data structure. Its dense grids represent terrain surface very well for some applications. However, ...