Get More Out of Variable Speed Limit (VSL) Control: An Integrated Approach to Manage Traffic Corridors with Multiple Bottlenecks [Brief]

69A3551747109Traffic congestion and the resulting stop-and-go motion of traffic on freeways increases travel delay, consumes more fuel and poses greater crash risks to motorists. Variable speed limit (VSL) control, where motorists are advised to travel under a lower speed limit on certain sections of the road, has been used to smooth traffic flow and reduce congestion. This project develops VSL control strategies to reduce fuel consumption and emissions on a freeway with multiple bottlenecks. The core objective is to minimize fuel use and emissions with no or minimal increase of travel time

Automated Analysis of Wildlife-Vehicle Conflict Hotspots Using Carcass and Collision Data [Brief]

69A3551747109Wildlife-vehicle conflict (WVC) occurs when traffic coincides with a place where animals decide to cross the surface of a roadway. State departments of transportation have a consistent need to understand rates and locations of WVC but inconsistent access to tools to measure statistical significance of clusters of WVC which could need mitigation. The project objective was to develop a standard method for analyzing WVC \u201chotspots\u201d (areas of concern) that any state could use to identify potential locations for WVC mitigation

Examining the Geography of Opportunity through a New Public Transit Opportunity Index [Brief]

USDOT Grant 69A3551747109The objective of this project is to develop a new index of geographic opportunity that improves upon existing measures to analyze the spatial relationship between the location of jobs and populations in urban settings. We develop a job accessibility measure based on Generalized Transit Feed Specification data which can be used to replace measures of actual commute times of workers and linear distance measures of job access to produce better estimates for job accessibility for the most vulnerable populations

Life Cycle Assessment of Environmental and Economic Impacts of Deploying Alternative Urban Bus Powertrain Technologies in the South Coast Air Basin [Research Brief]

To address issues of air quality and greenhouse gas emissions in the South Coast Air Basin, local transit agencies are considering shifting their urban buses to battery electric buses (BEBs) and hydrogen fuel cell electric buses (FCEBs). However, each of these options vary in their effectiveness in reducing emissions over their life cycle, associated life cycle costs and environmental footprint, and ability to meet operational needs

The Cost-Effectiveness of Alternative Policies for Reducing GHG emissions in the Freight Sector [Brief]

We develop a novel simulation that integrates aspects of route-level and multi-market models to evaluate the cost-effectiveness of alternative public policies that stimulate a faster adoption of cleaner technologies to reduce GHG emissions in the freight sector. The route-level model adds important spatial features that influence fuel consumption and fleet composition, such as nodes of pickup and delivery; while the multi-market model allows for adjustments in final prices, which in turn affect the sizes of fleet sectors and output markets. Most of the effort was in conceptualizing this integration and highlight its benefits. Preliminary simulations are conducted to illustrate the emissions that result from Phase 1 EPA regulations and ZEVs

Implications of Information Structure in Control of Urban Traffic Networks

69A3551747109Caltrans 65A0674 (TO-017)First, the authors consider optimal control of traffic flow over networks using a combination of variable speed limit, ramp meter, lane-changing, and routing control. While this problem has attracted significant attention, most of the prior work has been limited to centralized or open-loop control. The authors propose to develop the foundations for a framework to design closed-loop control under given information structures. The emphasis will be on computational tractability and characterization of performance gap with respect to centralized control. Second, the authors propose to study optimal information design to influence route choice decisions of drivers in dynamic environments. Specifically, the authors adopt the framework of algorithmic persuasion, under which the system planner can exploit information asymmetry about the knowledge of the real-time state of the network to release noisy information or recommend routes to the drivers in order to optimize social objective. The study of algorithmic persuasion in the context of routing games is very recent, and more so, the existing work implicitly assumes the drivers to evaluate the incentive compliant nature of the recommendations from the system planner only asymptotically, they do not consider externality from drivers who do not participate in persuasion, and assume static traffic flow models. In this project, the authors propose to address these shortcomings to develop foundations for algorithmic persuasion in routing games. The methodological contributions will be supplemented with case studies using traffic data from the Los Angeles area, and with simulation case studies in VISSIM

Race, Class, and the Production of and Exposure to Vehicular Pollution in Los Angeles [Brief]

69A3551747109Vehicular air pollution has created an ongoing public health crisis. Through a Los Angeles case study, we examine how different communities\u2019 driving volume and exposure to vehicular air pollution relate to race/ethnicity and socioeconomic status, and how this relationship varies across the region

Implementation of Action 6 of CSFAP Phase 2a Tracking Economic Competitiveness

USDOT Grant 69A3551747109 GO-Biz: 17GOB034This project continues earlier work aimed at implementing Action 6 of the California Sustainable Freight Action Plan (CSFAP). Action 6 requires the development of performance measures for monitoring the economic competitiveness of the freight sector, as well as the establishment of targets for increased economic competitiveness. The purpose of this project is to complete the performance measures and comparison groups, as well as to identify an appropriate economic competitiveness target. As with the previous stages of this research, the research team collaborated with the Economic Competitiveness Working Group. The Working Group includes representatives of various freight sectors, as well as public agencies. The project has resulted in a comprehensive set of performance measures and a complete set of baseline metrics and comparisons

Mobility, Accessibility and Disadvantaged Neighborhoods: Assessing Diversity in Transportation-Related Needs and Opportunities [Research Brief]

USDOT Grant 69A3551747109Caltrans No. 65A0674 TOThis project examines the commonalities and differences among disadvantaged neighborhoods in mobility and access to opportunities. Our approach utilizes the concept of spatial-transportation mismatch (STM), which hypothesizes that spatial distance and poor transportation are barriers to regional employment, and educational and health-care opportunities. The study compares one highly urbanized county (Los Angeles) and one more agricultural agriculture based (San Joaquin)

Ride-Hailing, Ridesharing, and Transit Ridership: A National Study Using the 2017 National Household Travel Survey

USDOT Grant 69A3551747109Caltrans Grant 65A0674Launched with the promise of \u201ccar-sharing\u201d reducing the need for private vehicle ownership, ridehail/TNC services such as Uber and Lyft have been in competition with transit agencies for riders ever since their emergence - prompting the question whether ridehail is a complement to or a substitute for transit. This study uses person-level data from the 2017 National Household Travel Survey and from a SACOG travel model (\u201cSACOG Replica\u201d) to evaluate the overlap between users of ridehailing (such as Uber and Lyft) and public transit riders, and whether the complementarity between modes varies across space. While usage of both transit and ridehailing is greater within half a mile of frequent rail service than further from stations, it is inconclusive whether the complementarity between modes varies with distance to rail transit. A second specification testing the relationship between transit and the portion of ridehail usage unexplained by demographics and land uses suggests that this association could result from individual preferences rather than the modes themselves being complementary. Further, ridehail trips peak at different hours than transit trips even among users of both modes, suggesting that the two modes serve different types of trips rather than ridehailing solving the transit first/last-mile problem