The Key Technology Of ITS Information Service System And Its Application

Nowadays ITS has became a focus in China and the whole world?In order to salve the aggravating problem of transportation , Governments > institutes and firms apply new technology to analysis the transportation requirement and apply information and communication technology to every part of traffic transportation and make good achievement . This thesis is the main content of my work in this field .This paper have eight chapters and is divided into four segments. First ,1 applied UML to establish the business model of the ITS information service system and find out the actors and use_cases of the ITS information service system .The model is a high system model of the ITS information service system. I sum up the key technology of the ITS information service system from the business model. Second , I establish the framework of the object_oriented geodatabase of generality GIS platform .GIS is a key technology of the ITS information service system .The store and organization of geographical data is a key problem of GIS and the efficiency of the store and visiting geographical data is an important performance of GIS. This paper generalize the definition of line , area of geographical object and the definition of spatial relationship in GIS . The paper applied the object_oriented technology to analyze the logic relationship of the spatial objects based these definition and to generalize the spatial object model . The spatial object model become the base of the framework of the object_oriented geodatabase . This paper also find out the bi_tree is a practicable imagery of the area in GIS and give a algorithm of the problem that if a point is in an area and analyze the time complexity of the solution based the imagery Third , the paper analyze some low algorithms of spatial analysis . The spatial analysis is an important component of GIS and distinguishes GIS from the general cartographic system and management information system . The spatial analysis performance is an important performance of GIS . The paper analyze some lowproblem of spatial analysis ,such as the relationship of point_lint , line_line ,line_box and find out highefficient algorithms of these problem. For example ,if we compare the algorithm in this paper with the algirithm by Pentium CPU , we will find the algorithmes in this paper canreduce time 24%~37% in theory. Fourth is the version control model of the object_oriented database and its application. The object_oriented database is an hot spot the researches into databases . The version control of the object_oriented database is an important mechanism of the multiuser concurrency control .Compared to the solid base_line of the general version control model,the paper present a mobile base_line.The four contents of this paper are well integrated with the ITS information service system. The business model of the ITS information service system is the high level model of the ITS information service system .The geographic information system is a key technology of the ITSinformation service system, the framework of the object_oriented geodatabase and the version control model of the object_oriented database are the key technology of the geographic information system , the low algorithms of spatial analysis is the core technology to enhance the GIS performance.All content of this thesis ,except the first part , have been applied in the general GIS platform of Cread corporation,Wuhan and is summary of my work in the design and implement of the platform framework and the spatial analysis algorithms. The general GIS platform of Cread is a new generation GIS platform .In order to reduce the platform development period and to enhance the reusing ability of platform ,we apply object_oriented technology to analysis the key technology and general problem of GIS . The platform in the lead of this field . The platform is working in a few province and city work as the base platform to manage and scheme land .