policy brief

Higher Bus Ridership Unlikely to Increase Community COVID-19 Transmission

Abstract

Public transportation has been blamed for facilitating the spread of COVID-19 in dense, urban areas. As a response to the COVID-19 pandemic, transit agencies have reduced service and implemented mask-wearing mandates and social distancing aboard transit. Some prior studies that address public transportation provide some evidence that negative COVID-19 outcomes are linked to high transit use. One early study of COVID-19 transmission on trains in China found that transmission is also affected by the density of passengers, seat spacing, and length of time traveled with other passengers aboard the trains.

Suggested Citation
David Brownstone and Henry Bernal (2021) Higher Bus Ridership Unlikely to Increase Community COVID-19 Transmission. Policy Brief. UC ITS. Available at: https://doi.org/10.7922/g2p26wgh.

policy brief

Shared Autonomous Mobility Services Show Promise for Increasing Access to Employment in Southern California

Abstract

Workers in Southern California currently face transportation related challenges accessing employment opportunities, including but not limited to high parking costs and/or limited parking availability in dense employment and residential areas; long commute distances between residential areas and employment opportunities; and poor transit service quality in many areas. These challenges are particularly burdensome for low-income households that may not have access to a personal vehicle and/or live in job-poor neighborhoods, as having a personal vehicle may be the only viable way to get to work.

Suggested Citation
Arash Ghaffar, Michael Hyland, Navjyoth Sarma, Suman Mitra and Tanjeeb Ahmed (2020) Shared Autonomous Mobility Services Show Promise for Increasing Access to Employment in Southern California. Policy Brief. UC ITS. Available at: https://doi.org/10.7922/g24f1p14.

working paper

The Impacts of Motor Vehicle Operation on Water Quality: A Preliminary Assessment

Abstract

Environmental studies of motor vehicles typically focus on air pollution or noise, but ignore water pollution. In this paper, we examine some of the impacts of motor vehicle transportation on non-point source and on groundwater pollution. Our estimates of the present value of costs for cleaning up leaking underground storage tanks and for controlling highway runoff for major arterials range from $45 billion to $235 billion, which is at least as much as noise damages. Our review of applicable measures suggests that effective policies should combine economic incentives, information campaigns, and enforcement measures, coupled with preventive environmental measures.

published journal article

Mitigating impacts associated with a high-penetration of plug-in electric vehicles on local residential smart grid infrastructure

Journal of Power Sources

Abstract

The transition to plug-in battery and fuel cell electric vehicles (PEVs) is emerging as a principal strategy to mitigate greenhouse gas (GHG) and criteria pollutant emissions. For PEVs, this paradigm shift requires attention to the impact of home charging on the grid in an era where distributed energy resources (DERs), such as solar panels and batteries, are being commercially deployed. To understand the integration of light-duty PEVs with residential DERs, a model is developed to simulate PEV charging demand profiles in combination with field data from three different home groups of varying DER configurations. A valley-filling smart charging algorithm is explored to optimize vehicle charging, more effectively utilize solar PV, reduce emissions, and reduce peak demand. The results show that (1) the impact on transformer hot spot temperature and loss of life is acceptable for all cases, (2) smart charging can increase transformer life, (3) while PEV deployment reduces GHG emissions, additional reduction can be achieved through the integration of DERs and smart charging, and (4) the addition of DERs and implementation of smart charging virtually eliminate the negative impacts of PEVs on distribution grid infrastructure, increases PV penetration, and reduces emissions and peak demand.

Suggested Citation
B. Hudson, G. Razeghi and S. Samuelsen (2024) “Mitigating impacts associated with a high-penetration of plug-in electric vehicles on local residential smart grid infrastructure”, Journal of Power Sources, 593, p. 233961. Available at: 10.1016/j.jpowsour.2023.233961.

working paper

Can Land Use Policy Really Affect Travel Behavior? A Study of the Link between Non-Work Travel and Land Use Characteristics

Publication Date

December 1, 1996

Associated Project

Working Paper

UCI-ITS-WP-96-15, UCI-ITS-AS-WP-96-5

Areas of Expertise

Abstract

Planners are increasingly viewing land use policies as a way to manage transportation demand. Yet the evidence on the link between land use and travel behavior is inconclusive. This paper uses travel diary data for Southern California residents to examine the demand for non-work travel. Both non-work automobile trips and non-work miles travelled by car are modelled as a function of individual sociodemographic variables and land use characteristics near the person’s place of residence. The land use variables are rarely statistically significant, and diagnostic tests suggest that land use (and thus residential location choice) is endogenous to non-work travel. The implications are twofold. The link between land use and non-work travel is weak at best, at least for the sample studied here, and future research should treat residential location and thus nearby land use characteristics as endogenous in models of travel behavior.

Suggested Citation
Marlon G. Boarnet and Sharon Sarmiento (1996) Can Land Use Policy Really Affect Travel Behavior? A Study of the Link between Non-Work Travel and Land Use Characteristics. Working Paper UCI-ITS-WP-96-15, UCI-ITS-AS-WP-96-5. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/7db9v4zb.

published journal article

Measuring the Built Environment with Google Street View and Machine Learning: Consequences for Crime on Street Segments

Journal of Quantitative Criminology

Publication Date

September 1, 2022

Author(s)

John R. Hipp, Sugie Lee, Donghwan Ki, Jae Hong Kim

Abstract

Despite theoretical interest in how dimensions of the built environment can help explain the location of crime in micro−geographic units, measuring this is difficult.

Suggested Citation
John R. Hipp, Sugie Lee, Donghwan Ki and Jae Hong Kim (2022) “Measuring the Built Environment with Google Street View and Machine Learning: Consequences for Crime on Street Segments”, Journal of Quantitative Criminology, 38(3), pp. 537–565. Available at: 10.1007/s10940-021-09506-9.

research report

Maximizing the Air Quality and Environmental Justice Benefits of Zero Emission Off-road Vehicles and Equipment in California

Abstract

Diesel fuel powered off-road vehicles and equipment used in agriculture, construction, mining, and industry have significant air quality and public health impacts due to high levels of pollutant emissions. Replacing these with zero emission powertrains represents a key strategy for reducing the harmful environmental impacts. However, the air quality impacts of zero emission off-road vehicles have not been assessed. Using the CMAQ model, we find that fully converting the off-road sector to zero emission equipment can decrease annual PM2.5 up to 0.9 μg/m3 and reduce daily maximum 8-hr average (MDA8) ozone as much as 6 ppb in Southern California. Statewide, these improvements yield benefits to public health potentially ranging up to $22.0 billion annually. The results further demonstrate the ability of zero emission off-road equipment to achieve health benefits within socially and economically disadvantaged communities.

Suggested Citation
Michael MacKinnon, Kai Wu and Scott Samuelsen (2025) Maximizing the Air Quality and Environmental Justice Benefits of Zero Emission Off-road Vehicles and Equipment in California. Available at: https://ezid.cdlib.org/id/doi:10.7922/G21Z42SX (Accessed: September 16, 2025).

research report

Fiscal and organizational impacts of part-time labor in public transit

Suggested Citation
Charles A. Lave, Genevieve. Giuliano and Kenneth M. Chomitz (1985) Fiscal and organizational impacts of part-time labor in public transit. Washington, DC: Office of Service and Management Demonstrations, Urban Mass Transportation Administration : Distributed in cooperation with Technology Sharing Program, Office of the Secretary of Transportation. Available at: https://catalog.hathitrust.org/Record/010607876.

published journal article

Evaluation of information applications of a self-organizing distributed traffic information system for a large-scale real-world traffic network

Computer-Aided Civil and Infrastructure Engineering

Publication Date

November 1, 2008

Author(s)

Suggested Citation
Xu Yang and Will Recker (2008) “Evaluation of information applications of a self-organizing distributed traffic information system for a large-scale real-world traffic network”, Computer-Aided Civil and Infrastructure Engineering, 23(8), pp. 575–595. Available at: 10.1111/j.1467-8667.2008.00557.x.

conference paper

One Year into the Pandemic: Heterogeneity in COVID- 19 Spread Patterns and Human Mobility Characteristics across US Counties

101st Annual Meeting of the Transportation Research Board (TRB)

Publication Date

January 1, 2022

Author(s)

Yusuf Sarwar Uddin, Rezwana Rafiq
Suggested Citation
Md Yusuf Sarwar Uddin and Rezwana Rafiq (2022) “One Year into the Pandemic: Heterogeneity in COVID- 19 Spread Patterns and Human Mobility Characteristics across US Counties”. 101st Annual Meeting of the Transportation Research Board (TRB).