The Research On The Key Technology Of Web GIS Path Planning

Nowday the Internet has become an important part of people’s life, based on the network of geographic information service life bring convenience for people at the same time also brought people know geography new ways of the world.This paper introduces the path planning of some key technologies in network environment, focused on the POI search, layered road network data organization and the shortest path search algorithm.Paper’s main work includes:(1) road network data model is introduced and the research status and existing problems of path planning algorithm, detailed discusses the road network topology relationship of data processing and storage, and puts forward the improved A*algorithm is proposed.(2) spatial database of interest points were introduced in this paper some of the concepts.Use Lucene.net toolkit, generate POI database index, and realize the function of POI search query.(3) in the organization of road network data, introduces the ideas of dual graph method to establish units of segmental arc topological relationship linked list, and the road network are hierarchical processing.(4)focuses on path query algorithm of graph theory in the classical Dijkstra and A*algorithms, this paper introduces the Dijkstra and A*algorithm for path and the calculation process, the time complexity of the two were analyzed.On this basis, put forward the improved A*algorithm, considering the road grade, traffic factors such as road conditions, the passage of time, in A*evaluation function is introduced into traffic capacity factor to estimate to expand segmental arc generation value, in order to plan A path is closer to the user’s expectations.(5) the author used the Visual Studio2010based on segment is A*, Duan Liqiong improved A*algorithm and the proposed considering traffic capacity of A*algorithm of path planning function, USES the real road network data, analysis of the above algorithm;Finally, the author combined with mentor project "navigation and location research on spatial information service platform technology requirements, the POI search and consider the traffic capacity of A*algorithm is applied to the project, good results have been achieved.