Research On Intelligent Processing Models For Moving Objects Data

Moving objects are the entities which positions and attribute changes with the time. Storing and handling of moving objects data are very importment for the application fields, such as traffic control, intelligent transportation systems (ITS), fleet management, digital battlefield, ecology / environment monitoring, mobile communication systems and communication networks, etc., The informations in these system are references with the location and time, including the real time geographic informations, more and more people concern the technology of that how to collect, model, store, query, analysis and process these spatiotemporal informations. The developments of object-oriented technology, spatial database, temporal database, and spatio-temporal database systems are primarily motivated by applications which track and present mobile objects. With the persistent progress of mobile communication and Internet, location based services become conceivable. Product related to it will be one of the primary value-added services which are supplied by network carrier to users. At present, location based technology and services are studied and developed at home and abroad, and many projects are brought forward.Research on the mobile data is an importment field of database management technology, Existing DBMS's are not well equipped to handle continuously changing data, and manage space and time informations, dynamic model of the moving objects, spatiotemporal query, and indexing, etc., the location of a moving object is inherently imprecise because the database location of the object isn't always same with the moving object, there exists some uncertainty between them. In this thesis, we aim at the models of moving objects expressing the dynamic attributes, and solve the problems in their designing, storing, indexing, and location update policy for moving objects data processing. This thesis presents some key issues of moving objects processing on moving objects modeling, storing and processing in following innovative achievements:(1) Proposing a dynamic model of moving objects data Based on the dynamic attributes of moving objects, we systematically propose a dynamic modeling of moving objects called trajectory, which can represents history, present and future data of moving objects by considering their generic feathres. Based on it, we design the object-oriented models of moving entities, describe the moving objects in the electronic map, present the uncertainty in space and time for moving objects, and the cost model and update policies of moving objectes, as well as the storing design for moving objects data in the database system.(2) Proposing a query model for moving objects dataWe analysis the query in spatial database, temporal database, and spatiotemporal database, introduce sequencing logic to moving objects query, combine the characters of the mobile objects, and propose a query model for moving objects data, on the basis of the model we proposed designing the query for position and time and moving as: where the objects is in given time? When the object arrive the given place? The relationship between the moving objects and the fixed space objects(point, line, area etc.) , the topology and the time reference of the multi-objects, notifying the moving objects at the special spatiotemporal event occure, querying of the past, now and future of moving objects, and continue querys. Finally we use the UDF(user define function) of DBMS to define the spatiotemporal operator and use the R-TREE to obtain the performance of point query, time query and moving objects with the fixed space object.(3) Proposing a agent model of moving objects based on extension of G-net Based on the distributed network architcture, proposing an intelligent agent tohandle the moving objects in the system, we give the application of distributed objects and intelligent agents, use extend G-net to simulate the behavior of the agent in the moving objects, present the general architecture of moving objects processing systm, and develop the application architecture. The development of computer technology impel that the software system architecture adopts multi-tie Client/Server architecture instead of mainframe architecture. Currently, more and more systems move to the 3-tier or multi-tier system because the latter one shows better in scalability and reusability together with the emerging of Web technology, which makes web browsers the client tier of m-tier system. My design partitions the application in two basic conceptual ways: multi-tier architecture and traditional modular decomposition. These make the whole system become a multi-tier component system, loose-couple horizontally and vertically, and provide security, flexibility, testability and extensibility.(4) Developing a distributed system for moving objects data based on GISWith the analysis of GPS location, GPRS communication, GIS technique as well as the distributed technology and intelligent agent, we studied mobile object intelligent processing technology on GIS application. The system is integrated by GPS location sub-system, GPRS communication sub-system and GIS map sub-system, which takes the advantages of GPS's full directions and precision, the GPRS always online and low cost, and GIS's electronic map. A mobile entity processing general module has been given out, to discuss the solution of mobile data wirelessly transferring. The representation of moving object in database, the query of moving object, and the moving object replay are also designed and developed. Also, with the B/S architecture, users can access the system through the Internet using mobile terminals anywhere easily.