Study On A Spatio-temporal Data Model Of Urban Public Traffic Based On GIS-T And Application

The data in urban public transport is characterized by the complicated spatio-temporal nature, which requires a scientific and efficient spatio-temporal data model to store and manage it. Due to deficiency in searching data and processing spatial relationship of spatio-temporal objects, however, traditional models built on base state with amendments have to be improved and expanded to meet specific application requirements. Data modeling is a key basis to establish a GIS application system. Thus, the construction of data model of urban public transport will lay the foundation for GIS-T application in this field.Firstly, based on theories of temporal GIS and spatio-temporal data models, the thesis ameliorates and enlarges the models built on base state with amendments and, on this basis and presents an approach of object-oriented spatio-temporal data model. Secondly, following the approach, this thesis builds a spatio-temporal data model of urban public transport and further provides some cases to examine this theoretical model. Finally, this model is employed in the design and development of GIS for planning of urban public traffic in Guangzhou, China, with further examination for this model being conducted.Specifically, targeting the existing problems of traditional models built on base state with amendments, this research proposes "critical index of object variation" to determine a base state interval and solves the problems of data store and search. To overcome the limitations of relational paradigm of relational database and object-relation GIS, an approach of event-driven and object-oriented spatio-temporal data modeling is presented in this thesis, which solves technical difficulties in object-oriented spatio-temporal data modeling. Through the approach of data modeling, a spatio-temporal data model better matches the nature of objective world, thus solving the arrangement problem of spatial data. The construction of data model of urban public transport has illustrated theoretical exploration in data modeling, which provides theoretical and methodological exploration for GIS data modeling and sets abasis for application of research results in urban public transport field. To process complicated spatial objects and maintain their temporal consistency, this thesis builds event-driven dynamic activity model and temporal model of urban public transport and expands temporal characteristics of spatial objects represented by temporal labeling. The application of this approach in developing GIS of urban public transport has successfully solved the issues of analysis and evaluation of public transport network beyond the traditional ones, which not only indicates theoretical advancement of this present research and applicability of its results, but also furnishes Guangzhou departments of transport management with some decision support in undertaking planning of urban public traffic.