The Construct Of Digital Space Of Global Mul-resolution Grid System And The Study Of Index Mechanism

With the development of earth-observation means, our interesting areas in dynamic remote-sensing inspecting are expanding from partial to global. Under this application background, it's not sufficient for global space information management demands with traditional plane data model, so an important research direction attracts our attention , that is a spherical data model of continuity, arrangement and dynamic. On the basis of managemental needs of global magnanimity space data, global multi-resolution grid system digital space construction and index mechanism are considerd, In this thesis, the emphasis is the creating of spherical grid which has potential of multi-resolution management, construction of global grid digital space, relationship between coding space and topological space, creating of partial high-precision grid and partial grid digital space. The followings are what we have done in this dissertation:1. The new designing steps and creating algorithm of storing-convenient, multi-resolution level index, potential management in icosahedrons dividing, hexagon unit global grid system are proposed, the geometry attributes difference with existing spherical hexagon grid are compared, on those bases, shortcomings of existing hexagonal index mechanism are analyzed and a new composing means is developed for spherical hexagonal grid pyramid.2. On the basis of spherical hexagon grid creating algorithm, a coding means of spherical grid pyramid structure is designed, we succeeded developing a digital grid space composed of coding space and topological space, discussing conversion problem from geodetic coordinates system to grid coding, proposing and realizing conversion algorithm based on hierarchical recursive discrete grid coordinate system, the veracity and reliability of computation can be assured.3. The foundermental manipulations such as seven scale operation, rotation operation and binary operation of coding space are defined, by making use of self-similarity between partial and whole coding space, we discussed some mutual operation and search algorithms including grid unit proximity search algorithm and hierarchical search algorithm, on the basis of coding space we can resume topological space of spherical grid successfully.4. The fundermental thought of partial high-precision grid forming and digital space construction are proposed, detailed edge problems of partial high-precision grid are analyzed, edge simplifying algorithm of spherical random polygon are studied, as well as co-relationship between points and spherical random polygon, grid district clipping based on span the developed surface, grid data hierarchical creating algorithm. On those bases, we developed partial grid digital space, discussed a seeking scheme of partial space in global grid digital space.