Mixed Spherical Degenerated Grid(MSDG) And Spatial Data Representation

With the rapid development of space exploration and information technology, thefast-accessed global mass spatial information raises new challenges to the organization,management, and representation of spatial data. Traditional division method of geographic spacebased on map projection and mappable unit can mainly resolve local problems and can basicallymeet the needs of application, but in dealing with global spatial information, its limitations suchas complex projection and lack of multi-scale integration management are gradually exposed.While spherical discrete grid provides a new way to solve the problems of lack of map projectionand multi-scale data management and so on. The main work and innovations are as follows:1. According to the division method of topographic map, a quadrilateral and triangleshybrid grid model-the hybrid spherical degradation quadtree grid model (Mixed SphericalDegenerated the Grid, the MSDG) is presented. Narrated the MSDG’s subdivision process,analysis and statistics of the MSDG geometric attributes are made. The results showed that: theMSDG model is layered, sub-heterogeneity, approximate equal in area, and other characteristics.2. According to division method of MSDG model and profile the degradation of themolecular unit distribution, the efficient quadtree index is chosen, a degenerative Z-filling curveto fill the grid cell is designed, and two encoding-degradation of the ranks of grid coding anddegradation of the quadtree grid coding are proposed. At the same time, the rank-degradationgrid encoding scheme and the neighboring search algorithm to determine the relationshipbetween grid cells are designed;3. By analyzing the distribution of the MSDG model sub-unit, the rank-degradation of thegrid code and quadtree-degradation of the coding to address coding and the geographiccoordinates of the two sets of coding schemes between positive operators of the conversionalgorithm and inverse conversion algorithm are respectively contra-posed. The accuracy of thealgorithm and coding precision of inverse conversion of the coordinate is analyzed;rank-quadtree degradation coding of positive and inverse operators of high efficiency, which is inline with the multilevel nature and multi-resolution features.4. Finally, in the proximity of the grid model, the encoding scheme and the grid cell todetermine the algorithm based on the judgment through the proposed slope method grid cell tofind the algorithm and the improved Bresenham grid cell search algorithm, the lattice vector linefeature network of expression.Through above-mentioned study, the main innovations of this composition are: 1. A spherical grid hierarchy, continuity, and an area-approximate-equal split model-thedegradation of mixed spherical grid model (MSDG) has been put forward, which can provide aviable split for the organization of the Global Spatial Data frame.2. According to the distribution of the MSDG unit, a degenerative Z-filling curve, thedesign of the two encoding-degradation in the ranks of the grid coding and degradation of thequadtree grid coding has been put forward, the degradation in the ranks of grid cells neighboringrelations to determine the algorithm has been given.3. Encoding for the MSDG designed two sets of positive operators of the encoding,inverse conversion algorithm has been designed.4. A slope-determined method grid unit to find algorithms, and improved the Bresenhamgrid unit to find the algorithm, Vector line elements of the path to fill has been put forward.