| The heavy reliance on single-occupant automobiles is a major contributor to congestion and poor air quality in metropolitan areas. One effective way to reduce vehicular emissions is to encourage urban travelers to switch from single-occupant auto to other travel modes, including public transit. The concept of personalized public transit relaxes the notion of fixed routes to improve access time. Once a call for transit service is received in the vicinity of an existing transit route, the transit vehicle is diverted to respond to the call. In this manner, flexible routes mimic the door-to-door attribute of a passenger car, thus substantially improving the attractiveness of the transit service to choice riders.; PPT software has been developed for the purpose of this project. The software provides the necessary tools for identifying the best diversion path for passenger pick up, modification of the network geometry and network continuity check. The service corridor has been constructed based on TIGER (Topologically Integrated Geographic Encoding and Referencing) Maps and transferred into ACCESS database (ACCESS is a Trade Mark of MicroSoft Corporation.) This database includes the network geometry, bus stop locations, route schedule, time points locations, available slack in the schedule, and turning prohibitions. The diversion path has to satisfy two major criteria. First that no near-side, far-side, and mid-block bus stops on the base route can be missed and second that usage of neighboring streets should be minimized during this diversion. The program takes the bus location and schedule adherence data, provided by the Dallas Area Rapid Transit (DART) Geographic Data System (GDS), as input variables and generates, among other time related information, the directions to the best Diversion path and the estimated time of arrival (ETA) to the location of the caller. The service will not be provided unless the resulted diversion time is less or equal to the available slack time between each pair of time points in every cycle. |
