dissertation, thesis, or capstone

The Effect of Bus lane Management Techniques on Operator Experience, Safety, and On-Time Performance

research report

Estimating the Pollution Abatement Potential of Electric Vehicle Subsidies

Abstract

The true net environmental benefit of an electric vehicle is relative to the vehicle that an electric vehicle buyer would have bought and driven had they not opted for an electric vehicle. This “counterfactual” vehicle cannot be observed, but its fuel economy can be estimated. We use a quasi-experimental variation in a generous California electric vehicle subsidy program to show that buyers of electric vehicles would have, on average, purchased fuel-efficient gasoline-powered cars had they not gone electric.

research report

Synthesis of State-level Planning and Strategic Actions on Automated Vehicles: Lessons and Policy Guidance for California

Abstract

This synthesis provides a summary and comparative analysis of actions states across the United States are taking in response to automated vehicles (AVs). The research focuses on state-level stakeholder forums (e.g., task forces, committees) and state-level strategic actions (e.g., studies, initiatives, programs) initiated by a state legislature, governor, or state agency. The analysis found that automated vehicle stakeholder forums and strategic actions address a diverse set of focus areas, but they pay minimal attention to the implications of automated vehicles on the environment, public health, social equity, land use, public transit, goods movement, and emergency response. Also, forums and strategic actions commonly include members from state transportation departments, the legislature, and academia; however, representatives from industry and non-governmental organizations (NGOs) are included less often. Academia and researchers participate in the majority of automated vehicle forums and actions, either in an advisory capacity (i.e., sharing expertise and experience) and/or through conducting research. Based on this analysis, the synthesis concludes with a recommendation for California to form a state-level working group representing leaders from the public sector, industry, non-governmental organizations, and academia to advise the Governor and the Legislature on automated vehicle policy across a range of focus areas.

dissertation, thesis, or capstone

Gaining Wait? Analyzing the Congestion Impacts of Road Diets in Los Angeles

research report

Vulnerability of California Roadways to Post-Wildfire Debris Flow

Publication Date

July 1, 2020

Author(s)

Mikhail Chester

Abstract

A vulnerability assessment of California roadways to post-wildfire debris flows is developed. The work examines current and future conditions, considering climate change scenarios and how they affect fire risk and precipitation. Results show how post-fire debris flow risks change from today into the future. A discussion is presented on how to prioritize investments considering the criticality of roadways within the broader network.

research report

Distraction ‘Hangover’: Characterization of the Delayed Return to Baseline Driving Risk After Distracting Behaviors

Abstract

Drivers know that smartphones distract them. Trying to limit distraction, drivers can use hands-free devices, where they only briefly glance at the smartphone. However, the cognitive cost of switching tasks from driving to communicating back to driving adds an underappreciated, potentially long period to the total distraction time. This project measured the effect of hands-free smartphones on driving behaviors by engaging ninety-seven 21- to 78-year-old individuals who self-identified as active drivers and smartphone users in a simulated driving scenario that included smartphone distractions. Peripheral cue and car-following tasks were used to assess driving behavior, along with synchronized eye-tracking. This research found that simulated driving performance drops to dangerous levels after smartphone distraction for all ages and for both voice and texting. The participants swerved for 15.1 seconds after a voice distraction and for a longer 20.6 seconds after a text distraction. Participants from the 71+ age group missed seeing about 50% of peripheral cues within 4 seconds of the distraction. Coherence with the lead car during the following task dropped from 0.54 to 0.045 during the distraction, and seven participants rear-ended the lead car.

published journal article

Induced Vehicle Travel in the Environmental Review Process

Abstract

If we expand roadway capacity, more drivers will come, or so economic theory suggests and a substantial body of empirical research now shows. Despite strong evidence, the “induced travel” effect is often ignored, underestimated, or misestimated in the planning process, particularly in the assessment of the environmental impacts of roadway capacity expansions. Underestimating induced travel will generally lead to an overestimation of the traffic congestion relief benefits a highway expansion project might generate, along with an underestimation of its environmental impacts. A major reason that induced travel tends to be underplayed in environmental analyses is that travel demand models do not typically include all of the feedback loops necessary to accurately predict the induced travel effect. We developed an online tool, based on elasticities reported in the literature, to facilitate the estimation of the induced vehicle travel impacts of roadway capacity expansion projects in California, with potential future expansion to other geographies. We describe the tool, apply it to five case study highway capacity expansion projects, and then compare the results with the induced travel estimates reported in the environmental impact analyses for those projects. Our results suggest that environmental analyses frequently fail to fully capture the induced vehicle travel effects of highway capacity expansion projects.