Modeling Reliability of Multimodal Transportation Networks

This research aims to study the reliability of transit and multimodal transportation system. The proposed approach is to study the factors contributing in travel time uncertainty, to develop mathematical relations for measuring such factors, and to use these factors in transit network models. The main models to work on are path algorithms and passenger assignment. Planned tasks are as following: Task 1: The study will begin with reviewing the literature in transportation system reliability. This includes studies on the definition and measurement of transit network reliability as well as studies on solving reliability-based routing problems. Task 2: The project will then select or propose appropriate measures that reflect reliability of a path in a transit network. Possible measures are standard deviation of travel time, probability of missing transit vehicles, variations in waiting time, etc. The process of calculating the proposed measures from available data will be studied. Task 3: Selected measures are then incorporated in transit path algorithms, such that instead of the shortest, the most reliable path can be calculated between an origin and a destination. This is the core part of the study and methodological contributions are anticipated upon completion of this task. Extensions to a transit passenger assignment model will be considered as well. Task 4: Research findings in terms of developed algorithms and possible case studies will be disseminated through journal articles and conference presentations during and after the completion of the study.