Research On The Application Of Dynamic Segmentation Technique In Utgis

Urban Traffic Geographic Information System (UTGIS) is a kind of thematic geographic information system in which GIS technique can be used on traffic management, and it is also a feasible way to solve the current urban traffic problems.In the research of UTGIS development, Data Model and the mode of data management are two key factors of system development successful or not, which decide the efficiency of system running. This thesis points out that the linear reference system and dynamic segmentation technique are key technologies to the description and expression of the complexity, linearity and dynamical characteristics of traffic information based on the analysis of existing UTGIS Data Model. After discussing the principles and methods of the linear reference system and dynamic segmentation technique, the thesis talks over the realization process of dynamic segmentation technique on Maplnfo data model, relying on scientific research and development (R&D) of the Geographic Information Sub-System of LuoYang's Urban Traffic Management System. First, design the Arc-Node data model and traffic network topology based on the Maplnfo data model, and then set up the linear reference system which adjusts to the urban transportation network system. In order to improve the precision and speed of dynamic segmentation calculation, we establish the projection arithmetic model based on road curve features, reconstruct the liner reference segment. And then we set up the dynamic segmentation data model based on the Maplnfo data model. Afterward considering special database characteristics of UTGIS, we design the UTGIS Geo-Database management mode and database layers, focusing on design of table structure of UTGIS Geo-Database based on dynamic segmentation thoughts. In the end, we develop a prototype system, discuss the application of dynamic segmentation technique in the traffic symbol management, traffic accident handling and the traffic congestion leading, and prove the practicability and validity of the linear reference system and dynamic segmentation technique in UTGIS.