ITS Berkeley

Energy Efficient Nonlinear Microscopic Dynamical Model for Autonomous and Electric Vehicles

Yeo, Yuneil
Lee, Jaewoong
Moura, Scott
Monache, Maria Laura Delle
2025

This article proposes a nonlinear microscopic dynamical model for autonomous electric vehicles (A-EVs) that considers battery energy efficiency in the car-following dynamics. The model builds upon the Optimal Velocity Model (OVM), with the control term based on the battery dynamics to enable thermally optimal and energy-efficient driving. We rigorously prove that the proposed model achieves lower energy consumption compared to the Optimal Velocity Follow-the-Leader (OVFL) model. Through numerical simulations, we validate the analytical results on the energy efficiency. We additionally...

Urban and Socioeconomic Disparities in PM2.5 Exposure Across 340 Latin American Cities

Ascencio, Edson J
Barja, Anthony
Montes-Alvis, Jose M
Kephart, Josiah L.
Gouveia, Nelson
Benmarhnia, Tarik
Diez Roux, Ana V.
Bilal, Usama
Miranda, J. Jaime
Carrasco-Escobar, Gabriel
Rodríguez, Daniel A.
2025

Background: Fine particulate matter (PM2.5) is a leading global health risk. Latin American cities exhibit some of the world's highest urban PM2.5 levels, yet studies on neighborhood-level PM2.5 exposure and associated disparities in the region are limited. Methods: We conducted a cross-sectional ecological analysis of 53,041 neighborhoods across 340 cities in eight Latin American countries, leveraging the SALURBAL dataset. Annual PM2.5 concentrations were derived from satellite data and linked to socioeconomic and urban characteristics. A multilevel model analyzed associations between...

Leveraging Commuting Patterns and Workplace Charging to Advance Equitable EV Charger Access

Wang, Ruiting
Kwon, Ha-Kyung
Jordan, Katherine H.
Moura, Scott
Boloor, Madhur
Machala, Michael L.
2026

This study introduces a framework for improving accessibility to and quantifying social equity priorities in electric vehicle charging infrastructure through strategic workplace charger placement. We develop a customizable equity evaluation model that quantifies access disparities across demographic groups. This model is used to construct an optimization framework that informs charging infrastructure deployment decisions. Leveraging commuting patterns, we demonstrate in the case study of Oakland, California that strategically placing workplace charging can achieve, on average, a 1.8-fold...

Beyond Centrality: Understanding Urban Street Network Typologies Through Intersection Patterns

Kuncheria, Anu
Walker, Joan L.
Macfarlane, Jane
2025

The structure of road networks plays a pivotal role in shaping transportation dynamics. It also provides insights into how drivers experience city streets and helps uncover each urban environment's unique characteristics and challenges. Consequently, characterizing cities based on their road network patterns can facilitate the identification of similarities and differences, informing collaborative traffic management strategies, particularly at a regional scale. While previous studies have investigated global network patterns for cities, they have often overlooked detailed characterizations...

Why do Immigrants Drive Less? Confirmations, Complications, and New Hypotheses from a Qualitative Study in New Jersey, USA

Chatman, Daniel G.
Klein, Nicholas J.
2013

Recent immigrants to the United States drive autos less than the US-born, with rapid increases in their ownership and use of autos over time, and a persistently lower level of auto use even when controlling for socioeconomic characteristics and time in the US. Quantitative studies have not yet explained these phenomena. Given that population growth in the US is largely dependent on immigration, understanding auto ownership and use among immigrants is important for transportation sustainability. We conducted six focus groups with US residents born in India, the Philippines, and Latin...

Using Disaggregate Vehicle Data to Investigate How Ride-Hailing Services Influence Personal Vehicle Use Across a Metropolitan Region

Montilla, Michael A. N.
Hui, Matthew
Chatman, Daniel G.
2025

App-based ride-hailing has become a popular form of urban transportation. Previous research suggests that it may in some cases enable lower reliance on private vehicles, but that it is also associated with increases in congestion and vehicle miles traveled (VMT). We examined how the introduction of the Uber ride-hailing service in the Boston area related to changes in the average daily VMT of individual vehicles. This research is unique because it focuses on the use patterns of individual automobiles instead of relying on aggregate measures of auto use, or estimates based on surveys, as...

Use of App-based Ridehailing Services and Conventional Taxicabs by Adults with Disabilities

Cochran, Abigail L.
Chatman, Daniel G.
2021

App-based ridehailing services such as Uber and Lyft are growing rapidly and serving more trips in large U.S. cities than conventional taxicabs, on which people with disabilities have historically depended. Analyzing the 2017 National Household Travel Survey, we found that adults with disabilities use app-based ridehailing at a much lower rate than adults without disabilities. This is partly because people with disabilities are older, have lower incomes, and live less in larger cities. But even when controlling for these factors, having a disability predicts lower use of app-based...

Transit Service, Physical Agglomeration and Productivity in US Metropolitan Areas

Chatman, Daniel G.
Noland, Robert B.
2014

Public transit improvements could cause more clustered and higher-density employment and enable urban growth, giving rise to agglomeration economies by improving labour market accessibility, increasing information exchange and facilitating industrial specialisation. Using data on US metropolitan areas, this paper traces the links from transit service to central city employment density, urbanised area employment density and population; and from these physical agglomeration measures to average wages and per capita GMP. Significant indirect productivity effects of transit service are found....

Transit Access and the Agglomeration of New Firms : A Case Study of Portland and Dallas.

Noland, Robert B.
Chatman, Daniel G.
Klein, Nicholas J.
2014

The objective of this paper is to examine whether new firms are more likely to form near rail transit stations. Two relatively new light-rail systems—one in Portland, Oregon, and the other in Dallas, Texas—form the basis of the analysis. A geocoded, time-series database of firm births from 1991 through 2008 is analyzed using all firm births, firm births of various sizes, and firm births of specific industry sectors. A random effects, negative binomial model is used to examine associations between proximity to rail stations and other spatially defined variables. Results show that newly...

Theory Versus Implementation in Congestion-priced Parking: An Evaluation of SFpark, 2011–2012

Chatman, Daniel G.
Manville, Michael
2014

Shortages of street parking can cause cruising, a major source of urban congestion. We used SFpark, a federally funded experiment in market-priced parking in San Francisco, to study how changes in meter prices influenced on-street parking availability. We supervised observations of more than 13,400 vehicles parked on a subset of dynamically priced and control blocks at three points in time during 2011 and 2012. Repeated-observation, change-on-change regressions show that when prices rose, the block-level occupancy of parking fell, suggesting that SFpark worked as intended. But blocks where...