INTEGRATING GIS CONCEPTS INTO TRANSPORTATION NETWORK DATA-STRUCTURES

Transportation network data structures must be designed to meet the re quirements of the analyses being conducted and must be compatible with the selected graphical user interface. Increasing interest in geograp hic information systems (GIS) and Intelligent transportation systems ( ITS) have further burdened the network data structure. It is possible to implement object oriented programming (OOP) technology to satisfy t hese needs, without making the data structure excessively complicated. This paper shows how a well-developed network data structure can inco rporate major capabilities normally associated with stand-alone GIS's. The design of a network data structure derives from both theoretical and practical considerations. A design of a network data structure, co mposed entirely of objects, is presented. Examples of its implementati on, limitations, advantages, and possible extensions are drawn from ex perience with the General Network Editor (GNE).