Old Models with New Tricks: Bridging the Gap in Bureau of Public Roads (BPR) Functions with A Cross-Resolution Perspective of Theoretical Fundamentals and Emerging Applications

In transportation planning, volume-delay functions (VDFs) are essential functions used for traffic assignment and network design problems. However, the static Bureau of Public Roads (BPR) function, created by the US Bureau of Public Roads in 1964, can only provide average travel time measures and cannot capture traffic dynamics at an oversaturated bottleneck. This talk will systematically review VDF-related research, including modeling efforts that connect traffic flow’s fundamental diagrams (FDs) to queueing models and link delay/performance functions under both undersaturated and oversaturated conditions. We will discuss a cross-resolution modeling approach for understanding the dynamic relationship between demand and supply and resulting congestion. We will also describe oversaturated system dynamics using parsimonious macroscopic analytical formulations with consistent mesoscopic queue vehicular fluid models. By providing a unified integration of multi-scale models, city planners can have a valid analytical framework to analyze queue saturation evolution processes. The effectiveness of this approach will be demonstrated through case studies using empirical data from heavily congested corridors in metropolitan areas, including New York, Los Angeles, and Phoenix. This talk will showcase how old models can be revitalized with new tricks to address the challenges of transportation planning and feedback-based control in the modern era.

PRESENTER

Xuesong (Simon) Zhou is an Associate Professor of Transportation Systems at the School of Sustainable Engineering and the Built Environment, Arizona State University (ASU), Tempe, Arizona. Dr. Zhou’s research focuses on developing methodological advancements in multimodal transportation planning applications, including dynamic traffic assignment, traffic estimation and prediction, large-scale routing, and rail scheduling. Dr. Zhou serves as an Associate Editor of Transportation Research Part C, an Executive Editor-in-Chief of Urban Rail Transit, and an Editorial Board Member of Transportation Research Part B. He was the former Chair of INFORMS Rail Application Section (2016) and currently serves as a subcommittee chair of the TRB Committee on Transportation Network Modeling (AEP40).

Dr. Zhou is the Director of the ASU Transportation+AI Lab, where he is the principal architect and programmer for several open-source packages, including DTALite, NEXTA, and OSM2GMNS, which have collectively received over 100,000 downloads and many system deployments at various metropolitan planning agencies and state DOTs. He has published over 100 papers in Transportation Research Part B, Transportation Research Part C, and other leading transportation journals, with an H-index of 54 and a total of 9,000 citations in Google Scholar.

In addition to his academic achievements, Dr. Zhou is passionate about connecting practitioners, researchers, academics, students, and others involved in transportation planning and travel modeling. He serves as the conference chair for the TRB Innovations in Travel Analysis and Planning Conference in 2023, and a board member of Zephyr Foundation, a non-profit organization dedicated to advancing transportation research and education.