Traffic Operations and Management

Adaptive Offsets for Signalized Streets

Daganzo, Carlos F.
Lehe, Lewis J.
Argote-Cabanero, Juan
2017

This paper shows that severe congestion on streets controlled by traffic signals can be reduced by dynamically adapting the signal offsets to the prevailing density with a simple rule that keeps the signals’ green-red ratios invariant. Invariant ratios reduce a control policy’s impact on the crossing streets, so a policy can be optimized and evaluated by focusing on the street itself without the confounding factors present in networks. Designed for heavy traffic with spillovers, the proposed policies are adaptive and need little data - they only require average traffic density readings and...

The Effect of Crosswalks on Traffic Flow

Knoop,Victor L.
Daganzo, Carlos F.
2018

In urban areas and especially in inner cities, pedestrians crossing the road considerably influence the road traffic flow. For political reasons, priority could be given to pedestrians. A larger number of crossings reduces the pedestrian load per crossing and facilitates both the pedestrian flow and the car flow; the ultimate case is a “cross anywhere” scenario. Earlier work shows that the road capacity decreases with the square of the pedestrian crossing time, hence a short crossing time is desired. Crosswalks can ensure pedestrians cross orthogonally, and thus quickly, and can thereby...

Effect of Transit Signal Priority on Bus Service Reliability

Anderson, Paul
Daganzo, Carlos F.
2020

As every user knows buses tend to bunch. To alleviate this problem, transit agencies introduce slack into their schedules and then hold buses back to schedule at pre-established control points along their routes. Unfortunately, this practice retards buses and only works with low frequency systems; i.e., when the headways are long. For higher frequency systems, which effectively operate without a schedule, headway-based control strategies show promise but unfortunately, they also retard buses. To alleviate bus retardation in all its forms, transit signal priority (TSP) is commonly used....

Traffic Signal Plans to Decongest Street Grids

Sadek, Bassel
Doig Godier, Jean
Cassidy, Michael J.
Daganzo, Carlos F.
2022

Two new synchronization strategies are developed for signalized grids of two-directional streets. Both strategies are found to reduce congestion significantly more than do other approaches. One of the strategies is static and the other adaptive. Both use a common timing pattern for all signals on the grid but use a different offset for each. The static strategy serves the morning rush by providing perfect forward progression on all streets in the directions that point toward a reference intersection, one that is located near the center of gravity of all workplaces. For the evening rush,...

Mobile Millennium Final Report

Bayen, Alexandre M.
Butler, Joe
Patire, Anthony D.
2011

Mobile Millennium is a research project that includes a pilot traffic-monitoring system that uses the GPS in cellular phones to gather traffic information, process it, and distribute it back to the phones in real time.

Eulerian Trilogy

Sun, Dengfeng
Yang, Samuel
Bayen, Alexandre M.
2012