published journal article

Traffic-related Air Pollution and Lung Cancer Incidence: The California Multiethnic Cohort Study

American Journal of Respiratory and Critical Care Medicine

Publication Date

October 15, 2022

Author(s)

Iona Cheng, Johnny Yang, Chiuchen Tseng, Jun Wu, Salma Shariff-Marco, Seri Park, Shannon M. Conroy, Pushkar P. Inamdar, Scott Fruin, Timothy Larson, Veronica W. Setiawan, Mindy C. DeRouen, Scarlett Lin Gomez, Lynne R. Wilkens, Loïc Le Marchand, Daniel O. Stram, Jonathan Samet, Beate Ritz, Anna H. Wu

View published journal article

Abstract

Rationale: Although the contribution of air pollution to lung cancer risk is well characterized, few studies have been conducted in racially, ethnically, and socioeconomically diverse populations. Objectives: To examine the association between traffic-related air pollution and risk of lung cancer in a racially, ethnically, and socioeconomically diverse cohort. Methods: Among 97,288 California participants of the Multiethnic Cohort Study, we used Cox proportional hazards regression to examine associations between time-varying traffic-related air pollutants (gaseous and particulate matter pollutants and regional benzene) and lung cancer risk (n = 2,796 cases; average follow-up = 17 yr), adjusting for demographics, lifetime smoking, occupation, neighborhood socioeconomic status (nSES), and lifestyle factors. Subgroup analyses were conducted for race, ethnicity, nSES, and other factors. Measurements and Main Results: Among all participants, lung cancer risk was positively associated with nitrogen oxide (hazard ratio [HR], 1.15 per 50 ppb; 95% confidence interval [CI], 0.99–1.33), nitrogen dioxide (HR, 1.12 per 20 ppb; 95% CI, 0.95–1.32), fine particulate matter with aerodynamic diameter <2.5 μm (HR, 1.20 per 10 μg/m3; 95% CI, 1.01–1.43), carbon monoxide (HR, 1.29 per 1,000 ppb; 95% CI, 0.99–1.67), and regional benzene (HR, 1.17 per 1 ppb; 95% CI, 1.02–1.34) exposures. These patterns of associations were driven by associations among African American and Latino American groups. There was no formal evidence for heterogeneity of effects by nSES (P heterogeneity > 0.21), although participants residing in low-SES neighborhoods had increased lung cancer risk associated with nitrogen oxides, and no association was observed among those in high-SES neighborhoods. Conclusions: These findings in a large multiethnic population reflect an association between lung cancer and the mixture of traffic-related air pollution and not a particular individual pollutant. They are consistent with the adverse effects of air pollution that have been described in less racially, ethnically, and socioeconomically diverse populations. Our results also suggest an increased risk of lung cancer among those residing in low-SES neighborhoods.

Suggested Citation

Iona Cheng, Juan Yang, Chiuchen Tseng, Jun Wu, Salma Shariff-Marco, Sung-shim Lani Park, Shannon M. Conroy, Pushkar P. Inamdar, Scott Fruin, Timothy Larson, Veronica W. Setiawan, Mindy C. DeRouen, Scarlett Lin Gomez, Lynne R. Wilkens, Loïc Le Marchand, Daniel O. Stram, Jonathan Samet, Beate Ritz and Anna H. Wu (2022) “Traffic-related Air Pollution and Lung Cancer Incidence: The California Multiethnic Cohort Study”, American Journal of Respiratory and Critical Care Medicine, 206(8), pp. 1008–1018. Available at: 10.1164/rccm.202107-1770OC.

research report

Development of the Capability-Enhanced PARAMICS Simulation Environment

Publication Date

April 1, 2005

Author(s)

Lianyu Chu, Henry Liu, Michael McNally, Will Recker

Final Report

UCB-ITS-PRR-2005-12

Areas of Expertise

Infrastructure Delivery, Operations, & Resilience

View research report

Abstract

This report summarizes research work conducted under TO4304 at the University of California, Irvine. Under this task order, the research team provided Caltrans with on-call direct support, technical guidance, and research related support. A series of Paramics plug-ins were developed and have been released to Caltrans. These plug-ins include actuated signal, multiple actuated signal timing plan, actuated signal coordination, detector data aggregator, ramp metering control, on-ramp queue override control, ALINEA ramp metering control, BOTTLENECK ramp metering control, SWARM Ramp metering control, and Freeway MOE. They complement the current Paramics simulation model and enhance its functionalities. This report describes how we developed these plug-ins and the step-by-step procedure to use them. It can be used as user manuals.

Suggested Citation

Lianyu Chu, Henry Liu, Michael McNally and Will Recker (2005) Development of the Capability-Enhanced PARAMICS Simulation Environment. Final Report UCB-ITS-PRR-2005-12. Institute of Transportation Studies, Irvine, p. 102p. Available at: https://escholarship.org/uc/item/5df164mw.

Phd Dissertation

Control Theoretic Approaches to Congestion Pricing for High-occupancy Toll Lanes

Publication Date

January 1, 2019

Author(s)

Xuting Wang

Areas of Expertise

Transportation Economics, Funding, & Finance Travel Behavior, Land Use, & the Built Environment

View Phd Dissertation

Abstract

The purpose of this study is to propose control theoretic approaches for high-occupancy toll (HOT) lanes operation. This dissertation considers different operation objectives, and provides pricing schemes for HOT lanes accordingly.To improve the system performance, the study first proposes a simultaneous estimation and control method for the same system as that in (Yin and Lou, 2009). An integral controller is applied to estimate the average value of time (VOT) of SOVs, and the dynamic prices are calculated based on the logit model. The closed-loop system is proved to be stable and guaranteed to converge to the optimal state both analytically and numerically. Two convergence patterns, Gaussian or exponential, are revealed. The effect of the scale parameter in the logit model is also examined.Then, a new lane choice model, i.e., the vehicle-based user equilibrium principle, is proposed to capture the lane choice of SOVs. A general lane choice model is derived based on the characteristics of the logit and the vehicle-based UE model. An insight regarding the dynamic price is obtained by analytically solving the optimal dynamic prices with constant demands of HOVs and SOVs, and then a feedback controller is designed to determine the dynamic prices without knowing SOVs’ lane choice models, but to satisfy the two control objectives: maximizing the flow-rate but not forming a queue on the HOT lanes. If the type of the lane choice model is given, the distribution of VOTs of the SOVs can be estimated.Next, an optimal control problem is proposed to examine the statement that revenue maximization should generally coincide with the optimization of freeway performances, such as maximizing overall travel-time savings or throughput. Results show that operators need to make different strategies based on the traffic demand. In order to maximize the revenue, operators should set a higher price to make the HOT lanes underutilized if the demand of HOVs is low. However, if the demand of HOVs is high, operators need to set a lower price to attract more SOVs to create congestion on the HOT lanes.It has long been known that drivers’ departure time choice behavior is one fundamental cause of congestion. In the last part of this dissertation, pricing schemes are proposed to consider both lane choice and departure time choice. In the study period, the demands for the HOT and GP lanes are higher than their capacities, which means the whole freeway is congested. However, the congestion period on the HOT lanes is short than that on the GP lanes. So, the HOT lanes are “underutilized”. It turns out that flat (instead of dynamic) pricing schemes are able to meet the following two constraints: (1) the total travel time and scheduling cost is minimized; and (2) the costs for each non-switching and switching SOV are the same. We show that different revenue and tolling constrains for certain type of vehicles lead to different pricing schemes.

Suggested Citation

Xuting Wang (2019) Control Theoretic Approaches to Congestion Pricing for High-occupancy Toll Lanes. Ph.D.. UC Irvine. Available at: https://escholarship.org/uc/item/0fs4t9kz (Accessed: October 12, 2023).

conference paper

New inductive signature data compression and transformation method for online vehicle reidentification

Proceedings of the 85th annual meeting of the transportation research board

Publication Date

January 1, 2006

Author(s)

Shin-Ting (Cindy) Jeng, Stephen Ritchie

Abstract

Traffic operations field computational resources as well as the bandwidth of field communication links are often quite limited. Accordingly, for on-line implementation of Advanced Transportation Management and Information Systems (ATMIS) strategies, such as vehicle reidentification, there is strong interest in development of fieldâ??based techniques and models that can perform satisfactorily while minimizing field computational and communication requirements. A new vehicle reidentification algorithm (REID-2) developed previously by the authors (1) was oriented toward algorithm simplification, but also demonstrated the added benefits of improved performance and much broader potential applicability (to both round and square single inductive loops) compared with earlier methods. However, the basis of REID-2 is directly matching inductive vehicle signatures, which typically consist of 200~1,200 data points (stored as integers, and obtained from IST-222 detector cards) per signature. The purpose of this research was to investigate if a relatively simple data compression and transformation technique could be applied successfully to the raw inductive signatures for each vehicle, and then use the resulting transformed vehicle signatures as inputs to vehicle reidentification. A Piecewise Slope Rate (PSR) approach was used to compress and transform the raw vehicle signatures. The results of this investigation, including sensitivity analyses, vehicle reidentification performance, and the accuracy of section travel time measurement, are very promising and suggest that the reduction in both computational effort and computer memory needed to store individual signatures with this approach could potentially benefit both the field computational and communication requirements needed for real-time implementation of this modified vehicle reidentification technique.

Suggested Citation

Shin-Ting (Cindy) Jeng and Stephen G. Ritchie (2006) “New inductive signature data compression and transformation method for online vehicle reidentification”, in Proceedings of the 85th annual meeting of the transportation research board, p. 26p.

published journal article

Enabling efficient offline mobile access to online social media on urban underground metro systems

IEEE Trans. Intell. Transport. Syst.

Publication Date

July 1, 2020

Author(s)

Di Wu, Lambros Lambrinos, Thomas Przepiorka, Dmitri Arkhipov, Qiang Liu, Amelia Regan, Julie A. McCann

View published journal article

Suggested Citation

Di Wu, Lambros Lambrinos, Thomas Przepiorka, Dmitri I. Arkhipov, Qiang Liu, Amelia C. Regan and Julie A. McCann (2020) “Enabling efficient offline mobile access to online social media on urban underground metro systems”, IEEE Trans. Intell. Transport. Syst., 21(7), pp. 2750–2764. Available at: 10.1109/tits.2019.2911624.

working paper

A Dynamic Analysis of Travel Demand

Publication Date

December 1, 1985

Author(s)

Thomas Golob, Leo J. G. van Wissen, Henk Meurs

Working Paper

UCI-ITS-WP-85-11

Areas of Expertise

Travel Behavior, Land Use, & the Built Environment

View working paper

Abstract

A panel data set is analysed with the goal of identifying patterns of change in the use of various modes of transport. The data set, which represents a national sample of the Netherlands, is comprised of over 2000 individuals surveyed in three waves six months apart in 1984 and 1985. The data were processed in the form of categorical variables depicting use or non-use of each mode at each wave and were analysed using log-linear models. Results indicated that there were significant patterns of change for all of the modes studied. Some of these patterns were interpreted as representing seasonality, while others were interpreted as representing more fundamental adjustments in travel behavior.

Suggested Citation

Thomas F. Golob, Leo van Wissen and Henk Meurs (1985) A Dynamic Analysis of Travel Demand. Working Paper UCI-ITS-WP-85-11. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/6464x49x.

conference paper

Vehicle reidentification with the inductive loop signature technology

Proceedings of the 10th international conference of eastern asia society for transportation studies (EASTS), taipei, taiwan

Publication Date

September 1, 2013

Author(s)

Shin-Ting (Cindy) Jeng, Chih-Lin (Albert) Chung, Lianyu Chu

Suggested Citation

S-T. Jeng and L. Chu (2013) “Vehicle reidentification with the inductive loop signature technology”, in Proceedings of the 10th international conference of eastern asia society for transportation studies (EASTS), taipei, taiwan.

published journal article

Local truckload pickup and delivery with hard time window constraints

Transportation Research Part B: Methodological

Publication Date

February 1, 2002

Author(s)

Xiubin Wang, Amelia Regan

View published journal article

Suggested Citation

Xiubin Wang and Amelia C. Regan (2002) “Local truckload pickup and delivery with hard time window constraints”, Transportation Research Part B: Methodological, 36(2), pp. 97–112. Available at: 10.1016/s0965-8564(00)00037-9.

published journal article

Environmental uncertainty and the timing of environmental policy

Natural Resource Modeling

Publication Date

June 1, 2008

Author(s)

Jean-Daniel Saphores

View published journal article

Suggested Citation

Jean-Daniel M. Saphores (2008) “Environmental uncertainty and the timing of environmental policy”, Natural Resource Modeling, 17(2), pp. 163–190. Available at: 10.1111/j.1939-7445.2004.tb00132.x.

published journal article

Fine Particulate Matter, Its Constituents, and Spontaneous Preterm Birth

JAMA Network Open

Publication Date

November 13, 2024

Author(s)

Anqi Jiao, Alexa N. Reilly, Tarik Benmarhnia, Yi Sun, Chantal Avila, Vicki Chiu, Jeff Slezak, David A. Sacks, John Molitor, Mengyi Li, Jiu-Chiuan Chen, Jun Wu, Darios Getahun

Areas of Expertise

Safety, Public Health, & Mobility Justice

View published journal article

Abstract

The associations of exposure to fine particulate matter (PM2.5) and its constituents with spontaneous preterm birth (sPTB) remain understudied. Identifying subpopulations at increased risk characterized by socioeconomic status and other environmental factors is critical for targeted interventions.To examine associations of PM2.5 and its constituents with sPTB.This population-based retrospective cohort study was conducted from 2008 to 2018 within a large integrated health care system, Kaiser Permanente Southern California. Singleton live births with recorded residential information of pregnant individuals during pregnancy were included. Data were analyzed from December 2023 to March 2024.Daily total PM2.5 concentrations and monthly data on 5 PM2.5 constituents (sulfate, nitrate, ammonium, organic matter, and black carbon) in California were assessed, and mean exposures to these pollutants during pregnancy and by trimester were calculated. Exposures to total green space, trees, low-lying vegetation, and grass were estimated using street view images. Wildfire-related exposure was measured by the mean concentration of wildfire-specific PM2.5 during pregnancy. Additionally, the mean exposure to daily maximum temperature during pregnancy was calculated.The primary outcome was sPTB identified through a natural language processing algorithm. Discrete-time survival models were used to estimate associations of total PM2.5 concentration and its 5 constituents with sPTB. Interaction terms were used to examine the effect modification by race and ethnicity, educational attainment, household income, and exposures to green space, wildfire smoke, and temperature.Among 409 037 births (mean [SD] age of mothers at delivery, 30.3 [5.8] years), there were positive associations of PM2.5, black carbon, nitrate, and sulfate with sPTB. Adjusted odds ratios (aORs) per IQR increase were 1.15 (95% CI, 1.12-1.18; P < .001) for PM2.5 (IQR, 2.76 μg/m3), 1.15 (95% CI, 1.11-1.20; P < .001) for black carbon (IQR, 1.05 μg/m3), 1.09 (95% CI, 1.06-1.13; P < .001) for nitrate (IQR, 0.93 μg/m3), and 1.06 (95% CI, 1.03-1.09; P < .001) for sulfate (IQR, 0.40 μg/m3) over the entire pregnancy. The second trimester was the most susceptible window; for example, aORs for total PM2.5 concentration were 1.07 (95% CI, 1.05-1.09; P < .001) in the first, 1.10 (95% CI, 1.08-1.12; P < .001) in the second, and 1.09 (95% CI, 1.07-1.11; P < .001) in the third trimester. Significantly higher aORs were observed among individuals with lower educational attainment (eg, less than college: aOR, 1.16; 95% CI, 1.12-1.21 vs college [≥4 years]: aOR, 1.10; 95% CI, 1.06-1.14; P = .03) or income (<50th percentile: aOR, 1.17; 95% CI, 1.14-1.21 vs ≥50th percentile: aOR, 1.12; 95% CI, 1.09-1.16; P = .02) or who were exposed to limited green space (<50th percentile: aOR, 1.19; 95% CI, 1.15-1.23 vs ≥50th percentile: aOR, 1.12; 95% CI, 1.09-1.15; P = .003), more wildfire smoke (≥50th percentile: aOR, 1.19; 95% CI, 1.16-1.23 vs <50th percentile: aOR, 1.13; 95% CI, 1.09-1.16; P = .009), or extreme heat (aOR, 1.51; 95% CI, 1.42-1.59 vs mild temperature: aOR, 1.11; 95% CI, 1.09-1.14; P < .001).In this study, exposures to PM2.5 and specific PM2.5 constituents during pregnancy were associated with increased odds of sPTB. Socioeconomic status and other environmental exposures modified this association.

Suggested Citation

Anqi Jiao, Alexa N. Reilly, Tarik Benmarhnia, Yi Sun, Chantal Avila, Vicki Chiu, Jeff Slezak, David A. Sacks, John Molitor, Mengyi Li, Jiu-Chiuan Chen, Jun Wu and Darios Getahun (2024) “Fine Particulate Matter, Its Constituents, and Spontaneous Preterm Birth”, JAMA Network Open, 7(11), p. e2444593. Available at: 10.1001/jamanetworkopen.2024.44593.