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This paper introduces the functional structure and framework of a universal GML schema-based parser. A valid algorithm for parsing various application schemas of GML is discussed in this paper. By making researches on intrinsic mechanism of core schemas, a set of grammatical and semantic parsing APIs are established to implement GML data parsing. The APIs would serve as the foundational operation collection for universal GML schema-based parsing engine.

In order to effectively solve the dynamic vehicle routing problem with time window, an insertion heuristic algorithm was proposed. In this algorithm, in order to reduce the time of searching routes, before searching all of the current routes, a set of candidate paths were selected by using GIS buffer analysis function under the new demand points. Meanwhile, the average satisfaction degree of customers, the traveling distance and the waiting time of vehicles are considered synthetically to optimize the increase of total cost caused by new customers. Finally, an example was presented to show the validity of the proposed algorithm.

Most of the 3D's data acquisition for buildings is a huge project, while the existing 2D data has not been fully exploited. This paper puts forward a method based on the existing 2D vector data to construct the simulated 3D map service. The key technique is to introduce the city 2D building's attribute “height” as elevation data, then based on the elevation data and the 2D geometric data, the simple 3D model can be constructed. After that, using the projection transformation and shear transformation to convert the simple 3D models to 2D data which have 3D visualization effect. Finally drawing the processed building data in 2D plane to achieve the 3D viewing effect. The proposed method is rapid flexible simplify and enhances people's sense of geospatial cognition.