published journal article

Measuring Air Carrier Passengers’ Values of Time by Trip Component

Transportation Research Record: Journal of the Transportation Research Board

Publication Date

January 1, 2016

Author(s)

Steven Landau, Geoffrey D. Gosling, Kenneth Small, Thomas Adler

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Abstract

This paper investigates how the value of airline passenger time varies by trip component and how the calculation of value of time can be related to capital investments specific to each component. Travel time is often a significant consideration in benefit–cost analysis for airport projects. The empirical results reported in this paper are based on a stated preference survey and subsequent model estimation. The survey used two conjoint exercises—one related to airport ground access and in-airport time components and a second covering attributes related to the flight itinerary. It was found that values of time differ by trip segment and travelers’ trip purpose.

Suggested Citation

Steven Landau, Geoffrey D. Gosling, Kenneth Small and Thomas Adler (2016) “Measuring Air Carrier Passengers’ Values of Time by Trip Component”, Transportation Research Record: Journal of the Transportation Research Board, 2569(1), pp. 24–31. Available at: 10.3141/2569-03.

conference paper

Electric Vehicles in Urban Delivery Fleets: How Far Can They Go?

Proceedings, 104th Annual Meeting of the Transportation Research Board

Publication Date

January 1, 2025

Author(s)

Dingtong Yang, Michael Hyland

Abstract

The goal of this study is to provide insights into the expected role of medium-duty electric vehicles (EVs) in urban delivery fleets and to analyze the effectiveness of EV subsidies on EV fleet penetration and tailpipe emissions. To meet this goal, we propose a modeling framework that determines the minimum-cost fleet size and fleet mix (of EVs and conventional vehicles) and vehicle routes for a profit-maximizing delivery company. Second, we conduct extensive analyses using this modeling framework and Southern California network data; we vary the EV driving range, per-mile cost of EVs, demand rate. We find that the optimal fleet mix nearly always includes EVs and conventional vehicles. Moreover, we find that EV subsidies have limited effectiveness with current EV batteries and service regions designed around conventional vehicles. Hence, improving EV battery technology is critical to electrifying urban delivery fleets.

Suggested Citation

Dingtong Yang and Michael Hyland (2025) “Electric Vehicles in Urban Delivery Fleets: How Far Can They Go?”, in Proceedings, 104th Annual Meeting of the Transportation Research Board. Washington, D.C..

published journal article

The bottleneck model: An assessment and interpretation

Economics of Transportation

Publication Date

March 1, 2015

Author(s)

Kenneth Small

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Suggested Citation

Kenneth A. Small (2015) “The bottleneck model: An assessment and interpretation”, Economics of Transportation, 4(1-2), pp. 110–117. Available at: 10.1016/j.ecotra.2015.01.001.

policy brief

New Tool from UC Irvine Could Save the State Millions while Providing Better Data on Truck Activity in California

Publication Date

October 1, 2019

Author(s)

Andre (Yeow Chern) Tok, Stephen Ritchie, Craig Rindt

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Abstract

Author(s): Tok, Andre; Ritchie, Stephen G.; Rindt, Craig

Suggested Citation

Andre Tok, Stephen G. Ritchie and Craig Rindt (2019) New Tool from UC Irvine Could Save the State Millions while Providing Better Data on Truck Activity in California. Policy Brief. Available at: https://escholarship.org/uc/item/12w5z2c8 (Accessed: October 11, 2023).

book/book chapter

Demand for Passenger Transportation

Publication Date

January 1, 2021

Author(s)

Kenneth Small, Robin Lindsey

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Suggested Citation

Kenneth A Small and Robin Lindsey (2021) “Demand for Passenger Transportation”, in International Encyclopedia of Transportation. Elsevier, pp. 127–133. Available at: 10.1016/B978-0-08-102671-7.10021-1.

conference paper

Improving Transit System Resilience Using Shared Autonomous Vehicles

Proceedings, 104th Annual Meeting of the Transportation Research Board

Publication Date

January 1, 2025

Author(s)

Arash Ghaffar, Jiangbo (Gabe) Yu, Michael Hyland

Abstract

This study investigates the use of shared autonomous vehicles (SAVs) to enhance the resilience of fixed-route transit systems. This study focuses on the strategic deployment of SAVs during disruptive events to serve stranded transit passengers alongside regular SAV travelers. The study begins by detailing the Santa Clara Valley Transportation Authority (VTA) Light Rail Transit (LRT) system, highlighting its capacities, challenges, and the potential improvements offered by SAVs. We present three disruptive scenarios. In the first scenario, a temporary transit disruption caused by an earthquake prompts the deployment of SAVs to transport stranded passengers to their homes or designated drop-off locations. The second scenario assumes a short-term transit operation disruption due to an earthquake in which SAVs transport stranded passengers to their homes or designated SAV drop-off locations. Third scenario examines a complete, long-term transit shutdown resulting from a safety/security issue, such as a mass shooting-induced multi-month system closure. We propose and deploy an agent-based model to test various SAV deployment strategies in these three scenarios to understand the improvement of performance metrics such as traveler wait time and delay in the disrupted transit system. The results provide a concrete demonstration of the promising role of SAVs during transit system disruption. Through the disruption scenarios, we provide insights into the performance under various fleet sizes and their availability of use. This study provides a valuable analysis for urban planners, transportation authorities, and policymakers interested in leveraging shared mobility and automation technologies for improved urban mobility resilience.

Suggested Citation

Arash Ghaffar, Jiangbo Yu and Michael F. Hyland (2025) “Improving Transit System Resilience Using Shared Autonomous Vehicles”, in Proceedings, 104th Annual Meeting of the Transportation Research Board. Washington, D.C..

published journal article

Energy policies for passenger motor vehicles

Transportation Research Part A: Policy and Practice

Publication Date

July 1, 2012

Author(s)

Kenneth Small

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Suggested Citation

Kenneth A. Small (2012) “Energy policies for passenger motor vehicles”, Transportation Research Part A: Policy and Practice, 46(6), pp. 874–889. Available at: 10.1016/j.tra.2012.02.017.

research report

Analyzing the 2012 California Household Travel Survey using R

Publication Date

February 11, 2016

Author(s)

Craig Rindt, Suman Mitra, Jean-Daniel Saphores

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Abstract

The 2010-12 CHTS, which resulted from a statewide, collaborative effort, enabled the collection of travel information from 42,560 Californian households. This rich dataset has helped update regional and statewide travel and will help update environmental models.In 2014, the Institute of Transportation Studies at Irvine (ITS) and Caltrans initiated the “Enhancing the Value of the 2010-12 California Household Travel Survey (CHTS)” contract. This contract was motivated by the idea that potential value of the CHTS is not always well understood by Caltrans staff and that some Caltrans staff from the Office of Travel Forecasting and Analysis may benefit from updating their knowledge of statistical modeling to comfortably query CHTS data and to estimate some common transportation econometrics models.This report provides numerous examples of how to perform various types of statistical analysis on the CHTS. In chapter 2, we discuss the R language and environment for statistical analysis, which was chosen as the primary analysis tool for this project. The following chapters provide specific examples of statistical analysis taken from the contract tasks. In all cases, the actual R code used to perform the analysis is provided, along with detailed discussion of the methods imployed. Chapter 3 describes the Task 1 diagnostic review of the CHTS. In chapter 4, we demonstrate the computation of statistical weights for various subpopulations in the CHTS—a critical component of any analysis involving the CHTS. In chapter 5, we cover the creation of a “linked trip” dataset, which provides a means for analyzing CHTS data in a manner that is compatible with conventional 4-step, trip based models. In chapter 6, we describe the creation of CHTS summary tables generated as part of task 3 work. Finally, chapter 7 describes the solution of a number of statistical queries that were answered under task 4 statistical support tasks.

Suggested Citation

Craig R. Rindt, Suman K. Mitra and Jean-Daniel Saphores (2016) Analyzing the 2012 California Household Travel Survey using R. Final Report. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/9n42t87s.

conference paper

The Rise of Self-Driving: Impacts on the Number, Size, and Location of Warehouses

Proceedings, 104th Annual Meeting of the Transportation Research Board

Publication Date

January 1, 2025

Author(s)

Lu Xu, Dewei Xiao, Saphores， Jean-Daniel

Abstract

With the arrival of autonomous driving technology, the logistics industry, particularly warehousing, is facing unprecedented changes. This study aims to explore how the expected drop in freight transportation costs due to truck automation may affect the number, size, and location of warehouses in a simple framework built around a monocentric city that receives supplies from a “port” located southwest of the city center. We formulated and solved a mixed-integer program that combine a static facility location model with a monocentric city model that provides simple estimates of population density and urban land rents. We found that as freight cost reduction increases from 0% to 90%, the optimum number of warehouses drops from 7 to 1, the average warehouse size expands from 8,125 to 10,833 square feet, drayage truck mileage drops by up to 24% while delivery truck mileage soars by up to 147%, for a net mileage increase of up to 18%. Our methodology and findings should be of interest to warehouse operators, retailers, and policymakers concerned with land use and environmental quality.

Suggested Citation

Lu Xu, Dewei Xiao and Saphores, Jean-Daniel (2025) “The Rise of Self-Driving: Impacts on the Number, Size, and Location of Warehouses”, in Proceedings, 104th Annual Meeting of the Transportation Research Board. Washington, D.C..

conference paper

SLAMSpoof: Practical LiDAR Spoofing Attacks on Localization Systems Guided by Scan Matching Vulnerability Analysis

IEEE International Conference on Robotics and Automation

Publication Date

February 19, 2025

Author(s)

Rokuto Nagata, Kenji Koide, Yuki Hayakawa, Ryo Suzuki, Kazuma Ikeda, Ozora Sako, Qi Alfred Chen, Takami Sato, Kentaro Yoshioka

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Abstract

Accurate localization is essential for enabling modern full self-driving services. These services heavily rely on map-based traffic information to reduce uncertainties in recognizing lane shapes, traffic light locations, and traffic signs. Achieving this level of reliance on map information requires centimeter-level localization accuracy, which is currently only achievable with LiDAR sensors. However, LiDAR is known to be vulnerable to spoofing attacks that emit malicious lasers against LiDAR to overwrite its measurements. Once localization is compromised, the attack could lead the victim off roads or make them ignore traffic lights. Motivated by these serious safety implications, we design SLAMSpoof, the first practical LiDAR spoofing attack on localization systems for self-driving to assess the actual attack significance on autonomous vehicles. SLAMSpoof can effectively find the effective attack location based on our scan matching vulnerability score (SMVS), a point-wise metric representing the potential vulnerability to spoofing attacks. To evaluate the effectiveness of the attack, we conduct real-world experiments on ground vehicles and confirm its high capability in real-world scenarios, inducing position errors of $geq$4.2 meters (more than typical lane width) for all 3 popular LiDAR-based localization algorithms. We finally discuss the potential countermeasures of this attack. Code is available at https://github.com/Keio-CSG/slamspoof

Suggested Citation

Rokuto Nagata, Kenji Koide, Yuki Hayakawa, Ryo Suzuki, Kazuma Ikeda, Ozora Sako, Qi Alfred Chen, Takami Sato and Kentaro Yoshioka (2025) “SLAMSpoof: Practical LiDAR Spoofing Attacks on Localization Systems Guided by Scan Matching Vulnerability Analysis”, in IEEE International Conference on Robotics and Automation. arXiv. Available at: https://ics.uci.edu/~alfchen/pubs/ken_icra25.pdf (Accessed: August 21, 2025).