Phd Dissertation

A multi-criteria decision making for prioritizing potential alternatives truck management strategies

Publication Date

January 1, 2008

Author(s)

Choong Heon Yang

Areas of Expertise

Freight, Logistics, & Supply Chain

View Phd Dissertation

Abstract

The objective of this dissertation is to develop a decision-making framework for prioritizing potential alternatives of truck management strategies using Multi-Criteria Decision-Making (MCDM) method. The motivation is drawn from the need for investigating and evaluating all likely impacts, resulting from the implementation of alternative truck strategies. The conventional evaluation methods such as the cost-benefit analysis can be addressed impacts involving monetary costs, but we believe these are insufficient to investigate all likely impacts. Our decision-making framework is developed to deal with all impacts that can transformable and non-transformable into monetary costs as well as to reflect decision-makers judgments. Two main objectives of this study are accomplished. The first is to explore all likely impacts, resulting from the implementation of alternatives truck management strategies, by performing a specific case study of before and after cases using traffic simulation models. A key feature of this part is to analyze various performance measures. They include both measures that can transformable and non-transformable into monetary costs as well as can reflect the standpoints of the public and the private sectors. Secondly, our framework is developed based on the Analytical Hierarchy Process (AHP), one of popular multi-criteria decision-making (MCDM) methods. This method enables the judgments and preferences of decision-maker to be quantified based on the relative importance of their own criteria, and to allow a quantitative interpretation from others. Another important contribution is to develop a 100-score conversion formula, a standard normalization technique. Since quantitative measurements have different scales, we need to incorporate these measurements into a single value. The formulas allow decision-makers to facilitate comparisons across potential alternatives. Final decision scores can be produced by multiplying the sum of scores of sub-criteria by estimated weight of the criteria. We believe that these final scores provide the argument to prioritize potential alternatives.

Suggested Citation

ChoonHeon Yang (2008) A multi-criteria decision making for prioritizing potential alternatives truck management strategies. Ph.D.. University of California, Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/u4evf/cdi_proquest_journals_304659069 (Accessed: October 14, 2023).

Phd Dissertation

Automatic discovery and diagnosis of security and safety defects in autonomous driving software

Publication Date

January 1, 2025

Author(s)

Ziwen Wan

View Phd Dissertation

Abstract

The technology behind Autonomous Driving (AD) is rapidly evolving, with companies like Waymo and Baidu already offering commercial robotaxi services in San Francisco and Wuhan, respectively, and Tesla planning its own service. Given the critical safety implications of AD systems, concerns about their reliability and security are slowing widespread adoption. To address these issues, it is essential to understand the boundary of how well AD vehicles handle unexpected real-world scenarios and how secure they are against potential attacks. Improving software testing and analysis techniques can enhance the safety and security of AD vehicles, accelerating their deployment. My dissertation focuses on enhancing testing and debugging in the AD software development life cycle through innovative automated tools. First, I analyzed the security of the AD software planning component and identified a new type of vulnerability: semantic DoS vulnerabilities, which can be exploited by real-world physical threats and have severe consequences. Second, I developed PlanFuzz, a new modular testing tool designed to efficiently discover zero-day semantic DoS vulnerabilities in the planning component. Unlike existing designs that rely on time-consuming and potentially buggy simulators, our novel approach directly connects fuzzing, the proven successful software testing techniques, with AD software testing for planning components. This significantly enhances the ability to discover new vulnerabilities within a realistic time frame. We evaluate PlanFuzz on 3 planning implementations from practical open-source AD systems, and find that it can effectively discover 9 previously-unknown semantic DoS vulnerabilities without false positives. Finally, I introduced an automated cause analysis tool for the AD software stack. This tool, which follows testing, efficiently and automatically identifies the root causes of discovered issues, enabling timely fixes for bugs and vulnerabilities. >98.5% of the manual efforts can be saved with such automated approach.

Suggested Citation

Ziwen Wan (2025) Automatic discovery and diagnosis of security and safety defects in autonomous driving software. PhD Dissertation. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/17uq3m8/alma991035687103704701.

published journal article

Going beyond the flood insurance rate map: Insights from flood hazard map co-production

Nat. Hazards Earth Syst. Sci.

Publication Date

April 1, 2018

Author(s)

Adam Luke, Brett F. Sanders, Kristen A. Goodrich, David L. Feldman, Danielle Boudreau, Ana Eguiarte, Kimberly Serrano, Abigail Reyes, Jochen E. Schubert, Amir AghaKouchak, Victoria Basolo, Richard Matthew

View published journal article

Suggested Citation

Adam Luke, Brett F. Sanders, Kristen A. Goodrich, David L. Feldman, Danielle Boudreau, Ana Eguiarte, Kimberly Serrano, Abigail Reyes, Jochen E. Schubert, Amir AghaKouchak, Victoria Basolo and Richard A. Matthew (2018) “Going beyond the flood insurance rate map: Insights from flood hazard map co-production”, Nat. Hazards Earth Syst. Sci., 18(4), pp. 1097–1120. Available at: 10.5194/nhess-18-1097-2018.

book/book chapter

Framing urban systems and planning concerns as a multi-level problem

Publication Date

January 1, 2011

Author(s)

Jae Hong Kim, G.J.D. Hewings

Suggested Citation

J.H. Kim and G.J.D. Hewings (2011) “Framing urban systems and planning concerns as a multi-level problem”, in N. Brooks, K. Donaghyand G. Knaap (eds.) The oxford handbook of urban economics and planning. Oxford University Press, pp. 674–700.

working paper

Travel Behavior Comparisons of Active Living and Inactive Living Lifestyles

Publication Date

September 1, 2006

Author(s)

Konstadinos Goulias

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

View working paper

Abstract

The past century’s radical change, innovation in transportation technology and concomitant increase in options for our travel modes moves us away from walking to an almost total extinction of modes that require physical exercise. This is accompanied by a modern American city design that requires the use of an automobile with urban sprawl creating distant destinations that alter older methods of travel and make active forms of transportation almost impossible. However, many more reasons exist that motivate people to choose physically inactive modes as our research shows here. Using a two-day activity diary collected in Centre County Pennsylvania, we identify which factors influence active versus inactive mode choice. In this analysis, we examine the correlation between trip purpose and travel mode, the correlation between age and travel mode, and perform an analysis of travel distances to determine what the distance threshold is for active modes. In addition, a latent class cluster analysis establishes a profile for both physically active as well as inactive travelers and their correlation with person and household characteristics. Key findings include that trips made using active modes are significantly different than trips made by inactive modes and persons with active transportation lifestyles are significantly different than persons with inactive lifestyles. This raises the following issue: policies designed for and motivated by persons with active lifestyles risk to fail if they do not succeed in meeting the needs for everyday life of those with inactive lifestyles.

policy brief

Potential Uses of Hydrogen in California’s Clean Energy Transition

Publication Date

September 1, 2022

Associated Project

Policy Brief Series on the Role of Hydrogen in California’s Transportation System

Author(s)

Lewis Fulton

Areas of Expertise

Zero-Emission Vehicles & Low-Carbon Fuels

View policy brief

Abstract

Currently, hydrogen is used in California in only a few significant applications, with refining being the most dominant. However, hydrogen has the potential to be a major zero-carbon energy carrier across many applications, including transportation, buildings, and various industries. What would be required for this kind of scale-up? What is the potential for hydrogen in different sectors and in different parts of the state? How can this potential be realized? Scaling up the use of hydrogen will likely require strong policies because currently it is produced on a small scale and is therefore expensive. This brief covers basic concepts of how hydrogen could be used, and how much end-use demand potential there could be for different applications across transportation, buildings and industry; however, it should be noted that this brief does not consider hydrogen used within the electricity system). It also considers strategy to some degree – such as where the greatest efforts should be placed. It builds on research that is ongoing on UC campuses as well as other sources.

Suggested Citation

Lewis Fulton (2022) Potential Uses of Hydrogen in California’s Clean Energy Transition. Policy Brief. UC ITS. Available at: https://doi.org/10.7922/g2sq8xq9.

Related Publications

policy brief | Sep 2022

Hydrogen Can Have a Much Lower Carbon Intensity than Fossil Fuels But This Largely Depends on How It Is Produced and Distributed

policy brief | Sep 2022

Can Green Hydrogen Be a Cost Competitive Transportation Fuel by 2030?

published journal article

Development of an intelligent system for automated pavement evaluation

Transportation Research Record

Publication Date

January 1, 1990

Author(s)

Stephen Ritchie, Mohamed Kaseko, B. Bavarian

Suggested Citation

S.G. Ritchie, M. Kaseko and B. Bavarian (1990) “Development of an intelligent system for automated pavement evaluation”, Transportation Research Record, 1311, pp. 112–119.

Phd Dissertation

PUBLIC TRANSPORTATION AT A CROSSROADS Transportation Network Companies, COVID-19, and Transit Ridership

Publication Date

January 1, 2022

Author(s)

Farzana Khatun

Areas of Expertise

Public Transit, Shared Mobility, & Active Transportation

View Phd Dissertation

Abstract

Public transportation in the U.S., including in California, was declining before COVID-19, and the pandemic made a bad situation much worse. In this dissertation, I analyze data from the 2009 and 2017 National Household Travel Surveys and from a California survey administered in May 2021 by IPSOS using both discrete choice (cross-nested logit and generalized ordered logit) and quasi-experimental (propensity score matching) tools first to investigate how Transportation Network Companies (TNCs, e.g., Uber and Lyft) impacted transit ridership before COVID-19, before analyzing how COVID-19 affected transit and other modes.In Chapter 2, my results for the U.S. show that individuals/households who use either public transit or TNCs share socio-economic characteristics, reside in similar areas, and differ from individuals/households who use neither public transit nor TNCs. In addition, individuals/households who use both public transit and TNCs tend to be Millennials or belong to Generation Z, with a higher income, more education, no children, and fewer vehicles than drivers. In Chapter 3, I quantify the impact of TNCs on household transit use by comparing travel for households from the 2017 NHTS (who had access to both transit and TNCs) matched with households from the 2009 NHTS (who only had access to transit) using propensity score matching. Overall, I find a 22% drop for weekdays (1.6 fewer daily transit trips by each household) and a 15% decrease for weekends (1.4 fewer daily transit trips by each household). In Chapter 4, I analyze how Californians changed transportation modes due to COVID-19 and explore their intentions to use different modes after COVID-19. I find that driving but especially transit and TNCs could see substantial drops in popularity after the pandemic. Many Hispanics, African Americans, Asians, lower-income people, and people who would like to telecommute more intend to use transit less. Key obstacles to a resurgence of transit after COVID-19 are insufficient reach and frequency, shortcomings that are especially important to younger adults, people with more education, and affluent households (“choice riders”). My findings highlight the danger of public transit entering into outsourcing agreements with TNCs, neglecting captive riders, and exposing choice riders to TNCs.

Suggested Citation

Farzana Khatun (2022) PUBLIC TRANSPORTATION AT A CROSSROADS Transportation Network Companies, COVID-19, and Transit Ridership. Ph.D.. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/u4evf/cdi_proquest_journals_2727675504 (Accessed: October 12, 2023).

conference paper

Characterizing Freight Trucks using Advanced Technology-Based Methods

100th Transportation Research Board (TRB) Annual Meeting

Publication Date

January 1, 2021

Author(s)

Andre (Yeow Chern) Tok

Suggested Citation

Andre Tok (2021) “Characterizing Freight Trucks using Advanced Technology-Based Methods”. 100th Transportation Research Board (TRB) Annual Meeting, Washington, DC.

conference paper

Functional modeling compiler for system-level design of automotive cyber-physical systems

2014 IEEE/ACM international conference on computer-aided design (ICCAD)

Publication Date

November 1, 2014

Author(s)

Arquimedes Canedo, Jiang Wan, Mohammad Al Faruque

View conference paper

Suggested Citation

Arquimedes Canedo, Jiang Wan and Mohammad Abdullah Al Faruque (2014) “Functional modeling compiler for system-level design of automotive cyber-physical systems”, in 2014 IEEE/ACM international conference on computer-aided design (ICCAD). IEEE, pp. 39–46. Available at: 10.1109/iccad.2014.7001327.