ITRAF, an object-oriented graphical user interface (GUI) for the Personal Computer (PC) Windows environment was designed at Oak Ridge National Laboratory to simplify the TRAF models input data process. Based on a link-node concept, ITRAF allows the user to graphically construct the network and input most of the required data by clicking buttons or dragging icons. Because of its object-oriented basis, ITRAF creates the data structures as the network is being developed, assigning TRAF default values to parameters and making guesses based on the topology of the network (such as the destination of the turning movements, for example). This reduces the effort in developing the data base in two ways. First, the user no longer needs to deal with the cumbersome data structure of the TRAF models (i.e., 80-column data cards utilizing numerical codes and adhering to strict formats), which is now created "behind the scenes" as he/she provides the geometric and traffic operational data graphically. And secondly, because ITRAF will anticipate in many instances the user's actions, thus reducing the number of steps to enter the data. ITRAF also provides extensive error checking which contributes further in alleviating the data input effort. (A)
Abstract