published journal article
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published journal article
Traffic-related air pollution and Parkinson’s disease in central California
ISEE Conference Abstracts
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Author(s)
Abstract
BACKGROUND AND AIM: Air pollution exposure may increase the risk of Parkinson’s Disease (PD). We assessed associations between long-term traffic-related air pollution exposures and PD in central California. METHOD: We generated air pollution exposures for 688 PD patients and 851 population controls enrolled in the Parkinson’s, Environment and Genes (PEG) studies 1 and 2. First, we estimated annual average carbon monoxide (CO) concentrations between 1981-2016 using the California Line Source Dispersion Model, version 4 (CALINE4) to model local traffic sources and, additionally, fine particulate matter (PM2.5) concentrations between 2000-2016 based on a high-resolution geoscience-derived model. Exposures were assessed as 10-year averaged CO and 5-year averaged PM2.5 prior to a PD diagnosis and a reference date in controls. We used logistic regression models to estimate odds ratios (OR) and 95% confidence intervals (95%CI), adjusting for age, sex, race, education, and study wave. RESULTS: For CO, each interquartile range (IQR) increase in 10-year average exposure prior to diagnosis was found to be associated with an OR of 1.06 (95% CI: 1.01-1.11) for residential and of 1.08 (0.99-1.18) for occupational address-based exposures. A per IQR increase in 5-year average PM2.5 prior to PD also increased the OR for PD at occupational address (OR=1.26; 95% CI 0.96-1.67). Associations were similar for 5- and 15-year exposure averages and were robust to adjustment for smoking or pesticide exposures. CONCLUSIONS: We found consistent evidence for positive associations between PD and long-term exposure to local traffic-related air pollution in central California measured by CO and PM2.5 at home and workplace addresses.
Suggested Citation
Beate Ritz, Dayoon Kwon, Jeff M Bronstein, Jun Wu and Kimberly C Paul (2023) “Traffic-related air pollution and Parkinson’s disease in central California”, ISEE Conference Abstracts, 2023(1). Available at: 10.1289/isee.2023.OP-277.published journal article
Real-time vehicle classification using inductive loop signature data
Transportation Research Record
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Suggested Citation
Shin-Ting (Cindy) Jeng and Stephen G. Ritchie (2008) “Real-time vehicle classification using inductive loop signature data”, Transportation Research Record, 2086(1), pp. 8–22. Available at: 10.3141/2086-02.conference paper
Efficient route guidance in vehicular wireless networks
2014 IEEE wireless communications and networking conference (WCNC)
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Author(s)
Suggested Citation
Yu Stephanie Sun, Lei Xie, Qi Alfred Chen, Sanglu Lu and Daoxu Chen (2014) “Efficient route guidance in vehicular wireless networks”, in 2014 IEEE wireless communications and networking conference (WCNC). IEEE, pp. 2694–2699. Available at: 10.1109/wcnc.2014.6952854.conference paper
Impacts of information technology on personal travel and commercial vehicle operations : Research challenges and opportunities
Proceedings of the 80th annual meeting of the transportation research board
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Abstract
Travel, like many other aspects of daily life is being transformed by the information technology revolution. Accessibility can no longer be measured only in terms of travel time, distance or generalized travel cost. Information technology gives people virtual accessibility to a rapidly growing range of activities. E-commerce has become a catalyst for structural changes in the freight transportation industry and is changing where freight moves, the size of typical shipments and the time within which goods must be delivered. In this paper we explore some of the potential effects of information technology on transportation, both personal and freight
Suggested Citation
Thomas F. Golob and Amelia C. Regan (2001) “Impacts of information technology on personal travel and commercial vehicle operations : Research challenges and opportunities”, in Proceedings of the 80th annual meeting of the transportation research board, p. 45 p..conference paper
DeepOpp: Context-aware mobile access to social media content on underground metro systems
2017 IEEE 37th international conference on distributed computing systems (ICDCS)
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Author(s)
Suggested Citation
Di Wu, Dmitri I. Arkhipov, Thomas Przepiorka, Qiang Liu, Julie A. McCann and Amelia C. Regan (2017) “DeepOpp: Context-aware mobile access to social media content on underground metro systems”, in 2017 IEEE 37th international conference on distributed computing systems (ICDCS). IEEE, pp. 1219–1229. Available at: 10.1109/icdcs.2017.269.published journal article
OAK-TREE: One-of-a-kind traffic research and education experiment
Transportation Research Record
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The creation and progress of OAK-TREE (One-of-a-Kind Traffic Research and Education Experiment) are chronicled. OAK-TREE is a traffic educational laboratory experiment that was developed and conducted at the University of California at Irvine (UCI) during the spring quarter of 1996. This project involved a cooperative effort between the academic community and public-sector transportation operating agencies in developing a comprehensive field and laboratory educational experience for undergraduate students in transportation engineering. The agencies involved in this effort were the Department of Civil and Environmental Engineering at the University of California at Irvine, the Advanced Traffic Surveillance and Control Center of the city of Los Angeles, the Transportation Management Center of the city of Anaheim, and the Irvine Traffic Research and Control Center of the city of Irvine. These agencies were instrumental in creating an innovative laboratory experience for academic training in the use of state-of-the-practice resources and methods for traffic engineering. The results were the development of a state-of-the-art traffic-control educational laboratory at UCI and the genesis of a unique traffic-control course that fulfilled the requirements of both fundamental academic education and rigorous professional training.
Suggested Citation
Carlos Sun, Wilfred Recker, Stephen Ritchie, Brian Gallagher, Eric Shen and John Thai (1997) “OAK-TREE: One-of-a-kind traffic research and education experiment”, Transportation Research Record, 1603(1), pp. 106–111. Available at: 10.3141/1603-14.Phd Dissertation
Modelling and Optimization of Smart Mobility Systems with Agent Envy as a Paradigm for Fairness and Behavior
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Abstract
Smart Urban Mobility in the future demands a paradigm shift. Transportation supply needs to be designed to incorporate individual-level preferences in an era of readily-available information about other users and network performance. It is, therefore, reasonable to expect that an individual would have information to compare his/her transportation allocation with other users. For individuals having the same goal (e.g., the shortest path to the destination from the same departure location and time), the peer to peer comparison may induce ‘envy’ if the user perceives his/her assigned travel option to be worse than that of his/her peers.In turn, a user may adjust his/her travel options until he/she does not feel envy. This concept is an extension of the well-known travel behavior assumption called “User Equilibrium”. Existing behavior models, however, do not allow users to compare their allocations with others on an individual basis. Furthermore, it is assumed that users have perfect information about their own alternative and all users are homogeneous. A smart mobility system of the future may also include users who are not human but machines such as logistics, an autonomous vehicle that may have programmed behavior, and thus they too can be considered “agents” in our analysis.This dissertation is dedicated to modeling a smart mobility system which accounts for individual level of allocation. Mobility systems that include connected, autonomous, and subscribed components to various extents will all qualify as smart systems in this context. More specifically, we focus on the optimization of the allocation problem to achieve both system-wide efficiency and minimum envy among individuals. We consider envy to be an important allocation aspect in the transportation system. Maximizing the efficiency of a system necessarily brings about some level of unfairness where some users (or agents) are allocated to inferior alternatives. When agents having superior alternatives can compensate the envy of groups having inferior alternatives, an envy-free state can be achieved—which can be shown to be Pareto efficient state. Using a combination of pricing and incentives, we propose an optimization model to arrive at this new equilibrium.This research has significant contributions in that the proposed model provides a framework to combine system-wide objectives with individual users’ utility objectives. Furthermore, we consider user heterogeneity, which has not been researched in the general area of transportation assignment. The proposed optimization model can be applied to pricing strategies both for commercial and public agencies, who have real-time information about customer characteristics and system performance.Numerical results from running our optimization on both illustrative and real networks show that the proposed model converges to both envy-free and system optimum states with appropriate allocation and pricing schemes. Our findings show that the proposed smart mobility system technically works efficiently without governmental subsidy since the budget-balance mechanism trades off credits among users. In addition, the level of user heterogeneity affects the amount of credits charged or disbursed.
Suggested Citation
Daisik Nam (2019) Modelling and Optimization of Smart Mobility Systems with Agent Envy as a Paradigm for Fairness and Behavior. Ph.D.. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/1gpb62p/alma991035165597104701 (Accessed: October 12, 2023).Phd Dissertation
Human Activity Recognition: A Data-driven Approach
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Areas of Expertise
Abstract
In this research, we propose a series of models designed to take advantage of the availability of data–both structured and unstructured–from a variety of sources ranging including passive data, questionnaires, and social media data to analyze underlying patterns and trends in travel and activity behavior, and to provide results that support enhancements both in transportation planning and the application of programming to support such efforts. First, we introduce a framework for automatically inferring the travel modes and trip purposes of human movement when tracked by a GPS device. We utilize a multiple changepoints algorithm to divide trajectories into segments using only speed data. Then, Random Forest is used to classify segments into moving and not-moving types. For moving segments, travel mode (car, bus, train, walk, and bike) is predicted. Next, multiple machine learning algorithms are employed, validated, and tested to identify the most suitable model for inferring trip purposes. The overall accuracy for prediction is over 80% on the testing set, both with and without data on socio-demographic variables. The model also predicts “shop” trips with an accuracy of 92.1%, while its accuracy for “go home” and “studying” trips reaches 100%. Additionally, we utilize the classification results in the first stage of research to compare households’ travel patterns from before a new light rail transit line began service to two periods of time after service began. Our results indicate that, although the average of activity duration varies significantly over days of week and waves, the random effect of these two factors on activity duration was minor; time of day contributed over one third of the total variance in the duration. Finally, the dissertation demonstrates uses of Twitter data as a potentially important data source to understand comments, criticisms, and responses about light rail in Los Angeles. The results of information flow analysis, sentiment estimation, topic modeling, and its application can be useful for exploring trends among commuters and how their sentiment changed according to the light rail line they used, the time of day, and the day of the week.
Suggested Citation
Thi Bich Thuy Luong (2015) Human Activity Recognition: A Data-driven Approach. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/1gpb62p/alma991016176269704701 (Accessed: October 12, 2023).conference paper
Accessibility in a metropolis - Toward a better understanding of land use and travel
Land development and public involvement in transportation: Planning and administration
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Author(s)
Abstract
An attempt was made to determine how accessibility affects aspects of long-term and short-term travel behavior. The accessibility indices that were used represent the ease with which opportunities for engagement in activities can be reached from a geographical zone in an urban area. The behavioral aspects examined include engagement in activities, automobile ownership and use, and travel patterns as represented by the number of trips, number of trip chains, and total travel time expenditure. Data from the Kyoto-Osaka-Kobe metropolitan area of Japan and the southern California coast are used to examine the following conjectures: time availability is more closely associated with engagement in activities than accessibility; accessibility no longer affects automobile ownership or use in the metropolises of industrialized countries where motorization has matured; and given automobile ownership and use, travel patterns are conditionally independent of accessibility.