INTERACTIVE NETWORK MODEL FOR ANALYSIS AND CARTOGRAPHIC DISPLAY OF RAILROAD TRAFFIC FLOW.

To implement provisions of Section 503 of the Railroad Revitalization and Regulatory Reform Act of 1976, the Federal Railroad Administration sponsored the development at Princeton University of an interactive computer graphics model of the U. S. rail system. The model has been implemented and applied to a number of railroad problems, including the flow of freight traffic, accident locations, flows of hazardous materials, traffic diversions, and Amtrak passenger volumes. Some of the problems encountered in the development of the network model and the data base are described, and examples of applications of the model are offered and illustrated with copies of the graphic displays produced for each study. The interactive system used for model development and implementation is discussed.