Displacement Model, Based On The Principle Of Automatic Generalization Of Elasticity

Automated generalization in cartography is a bottleneck in the development of GIS, which is also an international problem. And how to deal with the relationship of cartographic feature is one of the issues of cartographic generalization, while the displacement is an important way to deal with the relation. This thesis attempts to discuss how to solve the displacement by the theory of Elastic mechanics.An important premise of transferring the geo-spatial information is to express the spatial relation correctly. So that expressing the feature's spatial relation correctly is an important constraint to the work of displacement. Spatial relationship could be sorted into spatial topological relationship spatial mensural relationship and spatial azimuth relationship. Only after the work has considered all of the spatial relationship, good results of displacement could be obtained according to the principle of specifications of cartography.The characteristic of spread determines displacement's complicacy. Only when the work has controlled the spread of displacement and solved problem that it brings on, new conflicts could be avoided after the operation of displacement and correct spatial relationship could be ensured. The work also has to use an optimum method to solve the problem of displacement's spread. And there is an available way to reach this aim. That is a method based on the theory of Elastic mechanics.Based on targets' character, displacement could be divided into two parts, translation and deformation. Translation means targets moving as a whole without changing there shape character. And deformation means targets changing parts of there shape to solve the conflicts.The main researches of this thesis are:1. Achieving to explore the conflicts of targets and doing some analysis of the force bearing on the targets.2. Carrying out a spatial clustering on a basis of barriers and according to it the thesis expresses the spatial relationship of targets by using the Delaunay triangulation network and the minimum spanning tree. At the same time it regards a class as an elastomer to get the size of the displacement by simulating the deformation of the targets under the force.3. Achieving to aggregate the network targets and according to it regarding this aggregation as an elastomer. And then the work can get the size of the displacement with a plane pole model elastomer.