Theories And Implementation Technology On The Multi-Resolution Spatial Data Model

Two kinds of multi-resolution spatial data model are studied in this paper. One is the Feature Model and HOOM Model based on DLG data. The other is multi-resolution DEM Model based on terrain data using the algorithms of Self-Adaptive Triangular Regular Networks and Hierarchical Triangular Irregular Networks. Main works are concentrated on the following.Objected-oriented semantic relationships among feature objects are visualized by normalized Hypergraph model. Spatial data models are defined and designed in UML standard,which is useful to programming and implementation.By studying the relationships among resolution,map scale and scale. The conclusion is drawn that resolution feature is used as main scale characteristics of spatial data. Based on basic feature model,feature spatial relationship,semantic relationship keywords and formal theory are further presented. And HBDS model is extended to HOOM model. HOOM is an Objected-oriented integrated spatial model,which integrated geometric model,geographical feature model,geographical representation model,spatial calculation model and temporal model that based on Hypergraph model. A normal Object-oriented multi-resolution model is proposed to manage integrated multi-resolution spatial data that is DLG and DEM data.Spatial data model is formalized according to partial order relationship,equivalence relationship and simplicial complex theory. A formalizing two-tuple (M,F) multi-resolution spatial data model is presented. Based on the Jarno Peschie algorithms,an improved algorithm of road network map generalization is developed.Key issues on multi-resolution representation and real-time simplification algorithms of multi-resolution of terrain model are then studied,which are simplification algorithms of DEM,relativity calculation,off-line calculation,region division calculation,visibility calculation depending on FOV(Field of View) and error control,and real-time reality rendering. The simplification algorithms of self-adaptive triangulation regular networks and hierarchical triangulation irregular networks basically depending on FOV are thoroughly studied.In the end,based on theories and methods discussed in this paper,a GIS platform named HyperGIS and HyperTerrain of terrain visualization software are developed and implemented.