Phd Dissertation

Real option-based procurement for transportation services

Abstract

Uncertainty in transportation capacity and cost poses a significant challenge for both shippers and carriers in the trucking industry. In the practice of adopting lean and demand-responsive logistics systems, orders are required to be delivered rapidly, accurately and reliably, even under demand uncertainty. These tougher demands on the industry motivate the need to introduce new instruments to manage transportation service contracts. One way to hedge these uncertainties is to use concepts from the theory of Real Options to craft derivative contracts, which we call truckload options in this dissertation. In its simplest form, a truckload call (put) option gives its holder the right to buy (sell) truckload services on a specific route, at a predetermined price on a predetermined date. The holder decides if a truckload option should be exercised depending on information available when the option expires. Truckload options are not yet available, however, so the purpose of this dissertation is to develop a truckload options pricing model and to show the usefulness of truckload options to both shippers and carriers. Since the price of a truckload option depends on the spot price of a truckload move, we first model the dynamics of spot rates using a common stochastic process. Unlike financial markets where high frequency data are available, spot prices for trucking services are not public and we can only observe some monthly statistics. This complicates somewhat the estimation of necessary parameters, which we obtain via two independent methods (variogram analysis and maximum likelihood), before developing a truckload options pricing formula. Finally, a numerical illustration based on real data shows that truckload options would be quite valuable to the trucking industry. This dissertation develops a method to create value through more flexible procurement contracts, which could benefit the trucking industry as a whole—particularly in an uncertain business environment. Truckload rates and options prices are rigorously investigated and modeled. In addition, parameter estimation for a continuous stochastic model is explored using discrete statistics. Finally, numerical examples are illustrated and a picture of truckload option trading is presented. Results suggest that truckload options have the potential of significantly benefiting the trucking and logistics industries.

Suggested Citation
Mei-Ting Tsai (2008) Real option-based procurement for transportation services. Ph.D.. University of California, Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/1go3t9q/alma991035092933704701 (Accessed: October 14, 2023).

published journal article

Repeat wildfire and smoke experiences shared by four communities in Southern California: local impacts and community needs

Environmental Research: Health

Publication Date

September 1, 2024

Author(s)

Suellen Hopfer, Anqi Jiao, Mengyi Li, Anna Lisa Vargas, Jun Wu

Abstract

Abstract Families in unincorporated communities in Southern California’s Eastern Coachella Valley (ECV) increasingly experience the burden of repeat wildfires and smoke. This study describes their lived wildfire and smoke experiences, health impacts, unique community-level inequities that compound wildfire risk and air quality effects, communication preferences, and resource needs for future wildfire preparedness. A wildfire community vulnerability framework informed the focus group discussion guide, exploring individual, community, and local government level factors that potentially influence community response and mitigation behaviors to repeat wildfire and smoke. Ten focus groups with 118 participants occurred in spring 2023 with four communities in ECV, California. Findings center on narratives of acute wildfire-related experiences, including evacuation and burned trailer homes, acute and chronic self report physical and mental health impacts of wildfires and smoke, daily life disruptions, staying indoors for protection, and local interactions described as a community strength in responding to fires. Participants from unincorporated, low-income, and monolingual Spanish-speaking communities predominantly consisting of farm workers requested greater emergency preparedness and response information, training and education in Spanish, postfire resources, lower trash service fees, increased enforcement of illegal dumping and burning, and use of multimodal and bilingual communication channels for wildfire, smoke, and wind alerts.

Suggested Citation
Suellen Hopfer, Anqi Jiao, Mengyi Li, Anna Lisa Vargas and Jun Wu (2024) “Repeat wildfire and smoke experiences shared by four communities in Southern California: local impacts and community needs”, Environmental Research: Health, 2(3), p. 035013. Available at: 10.1088/2752-5309/ad6209.

conference paper

Studies of emergency evacuation strategies based on kinematic wave models of network vehicular traffic

2008 11th international IEEE conference on intelligent transportation systems

Publication Date

October 1, 2008

Author(s)

Kai-Fu Qiu, Wenlong Jin

Abstract

How to efficiently control traffic during emergency evacuation is an important research issue. An emergency evacuation strategy, one of the main control strategies, aims to identify the best routing strategy so as to fully utilize the available capacity of a transportation network. In this study, we model the evacuation traffic with a kinematic wave model of network vehicular traffic. We present two evacuation route guidance strategies: one is to maximize the total number of vehicles evacuated from the origin zone during a period of time, and the other is a myopic strategy based on local traffic supplies of downstream links at an intersection. The first strategy is an offline strategy and can be solved by a genetic algorithm, while the second one can be solved online. The performances of the proposed methods are tested with a simple road network.

Suggested Citation
Kai-Fu Qiu and Wen-Long Jin (2008) “Studies of emergency evacuation strategies based on kinematic wave models of network vehicular traffic”, in 2008 11th international IEEE conference on intelligent transportation systems. IEEE, p. 222+. Available at: 10.1109/itsc.2008.4732595.

conference paper

Determining optimal sensor locations under uncertainty for advanced truck surveillance on California freeways

Proceedings of the 97th annual meeting of the transportation research board

Publication Date

January 1, 2018

Abstract

A new hybrid sensor technology integrating existing Weigh-In-Motion (WIM) axle configuration data combined with inductive signature data obtained from advanced Inductive Loop Detectors (ILDs) is gaining interest due to its potential to provide detailed classification of truck body types as well as anonymous tracking of truck movements on freeways. This paper investigates two proposed strategies for optimally deploying this new technology on California freeways based on actual truck GPS trajectories: (1) A flow-interception approach to maximize the total amount of net origin-destination (OD) flows captured using integer programming; and (2) A truck re-identification approach to maximize insights into origins and destinations of sampled truck trips, as well as routes of those trips using Genetic Algorithm. The flow-interception model is capable of selecting locations emphasizing different body types with flow-based weight factors. The truck re-identification model investigates the best locations to identify heavy truck movement by selecting pairwise locations, and is shown to be sensitive to the re-identification performance uncertainty.

Suggested Citation
Jaeyoung Jung, Andre Tok and Stephen G. Ritchie (2018) “Determining optimal sensor locations under uncertainty for advanced truck surveillance on California freeways”, in Proceedings of the 97th annual meeting of the transportation research board, p. 6p.

published journal article

Joint mixed logit models of stated and revealed preferences for alternative-fuel vehicles

Transportation Research Part B: Methodological

Publication Date

June 1, 2000

Author(s)

David Brownstone, David Bunch, Kenneth Train

Abstract

We compare multinomial logit and mixed logit models for data on California households’ revealed and stated preferences for automobiles. The stated preference (SP) data elicited households’ preferences among gasoline, electric, methanol, and compressed natural gas vehicles with various attributes. The mixed logit models provide improved fits over logit that are highly significant, and show large heterogeneity in respondents’ preferences for alternative-fuel vehicles. The effects of including this heterogeneity are demonstrated in forecasting exercises. The alternative-fuel vehicle models presented here also highlight the advantages of merging SP and revealed preference (RP) data. RP data appear to be critical for obtaining realistic body-type choice and scaling information, but they are plagued by multicollinearity and difficulties with measuring vehicle attributes. SP data are critical for obtaining information about attributes not available in the marketplace, but pure SP models with these data give implausible forecasts. (C) 2000 Elsevier Science Ltd. All rights reserved.

Suggested Citation
David Brownstone, David S. Bunch and Kenneth Train (2000) “Joint mixed logit models of stated and revealed preferences for alternative-fuel vehicles”, Transportation Research Part B: Methodological, 34(5), pp. 315–338. Available at: 10.1016/s0191-2615(99)00031-4.

published journal article

Real-time truck characterization system: A pilot implementation of the Freight Mobility Living Laboratory (FML2)

Transportation Research Interdisciplinary Perspectives

Abstract

California possesses multiple major freight gateway and logistics facilities that serve both the state and the entire U.S. But the economic, environmental, and local community impacts of trucks, especially heavy-duty trucks that are currently essential to our supply chains and freight transportation system remain poorly measured due to the lack of comprehensive and detailed truck activity data. This paper describes the pilot implementation of the real-time, scalable, and cost-efficient Freight Mobility Living Laboratory (FML2). This system provides truck characterizations across multiple attributes, such as truck body types, axle-based and Gross Vehicle Weight Rating (GVWR)-based classification and is currently deployed at 30 detection locations in Southern California along major freight corridors to support freight modeling and analysis needs. This paper details the design of the FML2 from edge data processing, predictive model development, communication architecture, and backend data storage to the real-time data dashboard to visualize the classification results. Three case studies have been presented at the end of the paper to demonstrate the potential of FML2 for use by both researchers and practitioners to gain further insights on truck activities.

Suggested Citation
Yiqiao Li, Andre Y. C. Tok, Guoliang Feng and Stephen G. Ritchie (2024) “Real-time truck characterization system: A pilot implementation of the Freight Mobility Living Laboratory (FML2)”, Transportation Research Interdisciplinary Perspectives, 27, p. 101212. Available at: 10.1016/j.trip.2024.101212.

published journal article

The cost of convenience; Air pollution and noise on freeway and arterial light rail station platforms in Los Angeles

Transportation Research Part D: Transport and Environment

Publication Date

December 1, 2016

Author(s)

Abstract

Light rail transit (LRT) systems constitute one of the most sustainable public transportation modes and transit agencies have increasingly constructed LRT lines along the median of roadways to reduce land acquisition costs and traffic conflicts. Despite these conveniences, few studies have examined the air pollution and noise exposures for passengers on LRT station platforms within freeway or arterial medians. In response, we monitored particle number count (PNC) concentrations and noise levels on 17 station platforms in the Los Angeles metro system in summer 2012 and assessed differences between freeway and arterial platforms. We visited each station On average 7 times for approximately 19 min with two teams carrying a full set of instruments. As expected, impacts were higher on green line platforms in the center of a grade-separated freeway compared to blue line platforms in the center of an arterial due to being in close proximity to greater traffic volumes. Overall, freeway-arterial platform differences were 35,100 versus 20,000 particles/cm(3) for PNC and 83 versus 62 dBA for noise. This average noise intensity on green line platforms was four times that on blue line stations. We also found that PNC concentrations were significantly higher at open air monitoring platform positions compared to standing under a shade canopy (about 2000 particles/cm3 higher), but that noise levels were significantly lower at open air positions compared to under canopy positions (about 3.2 dBA lower). Results identify important factors for transport planners to consider when locating and designing in-roadway LRT platforms. (C) 2016 Elsevier Ltd. All rights reserved.

Suggested Citation
Douglas Houston, Andy Dang, Jun Wu, Zohir Chowdhury and Rufus Edwards (2016) “The cost of convenience; Air pollution and noise on freeway and arterial light rail station platforms in Los Angeles”, Transportation Research Part D: Transport and Environment, 49, pp. 127–137. Available at: 10.1016/j.trd.2016.09.011.

Phd Dissertation

Assessing Benefits and Costs of Urban Environmental Attributes in a Hedonic Framework: Three Southern California Case Studies

Abstract

This dissertation research focuses on understanding benefits or costs of some urban amenities and disamenities using the Hedonic Pricing (HP) method. It includes three Southern California case studies where different hedonic models (fixed effects, spatial Durbin model, and geographically weighted regression) are estimated to obtain unbiased and consistent parameter estimates. In the first case study, I analyze 20,660 transactions of single family detached houses sold in 2003 and 2004 in the city of Los Angeles, CA, to estimate the value of urban trees, irrigated grass, and non-irrigated grass areas. I rely on fine-grained hedonic models with many covariates to control for unobserved neighborhood characteristics. I find that Angelenos like lawns: 78 percent of the properties examined would gain value with additional irrigated grass in their neighborhood and even more (83 percent) on their parcel. However, additional parcel trees would decrease the value of almost half (46 percent) of the properties examined and they would have only a small positive impact on most of the others. By contrast, additional neighborhood trees would slightly increase the value of over 80 percent of the properties analyzed. This suggests that while Los Angeles residents may want additional trees, they are unwilling to pay for them. These results have implications for urban tree planting programs that rely primarily on private property owners. The second case study quantifies the impact of urban green spaces on the value of 1,197 multifamily buildings sold in 2003-2004 in the city of Los Angeles, California; these green spaces are either on their parcels or in their vicinity (an area 200 meters outward of each parcel boundary). It is necessary to examine multifamily houses separately because they belong to a different market. To assess the robustness of the results, I contrast a spatial Durbin model with a geographically weighted regression model and conduct an extensive sensitivity analysis. I find that increases in grassy areas either on the parcels of multifamily buildings or in their vicinity would typically not enhance their value, and neither would more parcel tree canopy cover (TCC); by contrast, most multifamily properties would benefit from an increase in vicinity TCC. These results suggest that most multifamily building owners have no incentives to increase the tree canopy cover or the grassy areas on their properties. In the third case study, I investigate the impact of freeway traffic on property values using hedonic pricing models, with a particular interest for truck traffic. I analyze 4,715 sales of single family houses that took place in 2003 and 2004 in part of the busy transportation corridor that links the Ports of Los Angeles and Long Beach to downtown Los Angeles. These houses are located at least 200 meters from the nearest arterial road to filter out the impact of traffic on arterial roads. In order to minimize the risk of omitted variable bias and spatial autocorrelation, I estimate a fine-grained fixed effects model. I find that a one percent increase in the proportion of truck traffic could decrease the value of a $420,000 house located between 100 and 400 meters from the nearest freeway by between $2,000 and $2,750. These results are important for policy makers and owners of single family houses located close to freeways as the ports of Los Angeles and Long Beach are forecasting sharp increases in drayage truck activity as the economy recovers.

Suggested Citation
Wei Li (2011) Assessing Benefits and Costs of Urban Environmental Attributes in a Hedonic Framework: Three Southern California Case Studies. Ph.D.. University of California, Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/17uq3m8/alma991010645479704701 (Accessed: October 13, 2023).

conference paper

Dirty road can attack: Security of deep learning based automated lane centering under {Physical-World} attack

30th USENIX Security Symposium (USENIX Security 21)

Publication Date

January 1, 2021

Author(s)

Takami Sato, Junjie Shen, Ningfei Wang, Yunhan Jia, Xue Lin, Qi Alfred Chen
Suggested Citation
Takami Sato, Junjie Shen, Ningfei Wang, Yunhan Jia, Xue Lin and Qi Alfred Chen (2021) “Dirty road can attack: Security of deep learning based automated lane centering under {Physical-World} attack”, in 30th USENIX Security Symposium (USENIX Security 21), pp. 3309–3326. Available at: https://www.usenix.org/conference/usenixsecurity21/presentation/sato (Accessed: October 11, 2023).

published journal article

Economic valuation of the taehwa field ecological park: An application of a contingent valuation method with preference uncertainty

journalofenvironmentalpolicy

Publication Date

March 1, 2010

Author(s)

Suggested Citation
Jae Hong Kim (2010) “Economic valuation of the taehwa field ecological park: An application of a contingent valuation method with preference uncertainty”, journalofenvironmentalpolicy, 9(1), pp. 109–135. Available at: 10.17330/joep.9.1.201003.109.