published journal article

Arterial bus lane warrants

Australian Road Research

Publication Date

January 1, 1978

Author(s)

Suggested Citation
S.G. Ritchie (1978) “Arterial bus lane warrants”, Australian Road Research, 8(4), pp. 63–67.

conference paper

An approximate least-square Monte-Carlo algorithm for solving the multi-period continuous network design problem

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

Publication Date

January 1, 2018

Abstract

This paper proposes a new algorithm to solve the Multi-period Continuous Network Design Problem (MPCNDP) in a real options framework. The MPCNDP aims to find the long-term optimal highway expansion plan for a road network with stochastic demand. Analytical methods, finite difference methods or Least Square Monte Carlo simulation (LSMC) are not applicable for solving the MPCNDP because of the high dimension of the stochastic demand variables and the complexity of the intrinsic complexity of the network design problem. The authors propose an algorithm, which they call â??Approximate Least Square Monte Carlo simulationâ?? (ALSMC). This algorithm applies least square regression to estimate the value of the termination payoff function without knowing the optimal capacity improvement plan. During each iteration, only a multi-period CNDP with deterministic demand needs to be solved, which dramatically reduces the computing time of each termination payoff function. The authors first test the ALSMC method on a simple example for which the exact solution is known, and show that it converges quickly to the solution. They then test the ALSMC method on a small network with 6 centroids and 16 links, which has been used as a benchmark in dozens of papers. The authors find that the ALSMC method gives quick and reasonably accurate estimates of the termination payoff function.

Suggested Citation
Ke Wang and Jean-Daniel M. Saphores (2018) “An approximate least-square Monte-Carlo algorithm for solving the multi-period continuous network design problem”, in Proceedings of the 97th annual meeting of the transportation research board, p. 18p.

published journal article

Microsimulation of flexible transit system designs in realistic urban networks

Transportation Research Record

Suggested Citation
Cristián E. Cortés, Laia Pagès and R. Jayakrishnan (2005) “Microsimulation of flexible transit system designs in realistic urban networks”, Transportation Research Record, 1923(1), pp. 153–163. Available at: 10.1177/0361198105192300117.

published journal article

The process of information propagation in a traffic stream with a general vehicle headway: A revisit

Transportation Research Part C: Emerging Technologies

Publication Date

June 1, 2010

Author(s)

Bruce (Xiubin) Wang, Teresa M. Adams, Wenlong Jin, Qiang Meng
Suggested Citation
Bruce (Xiubin) Wang, Teresa M. Adams, Wenlong Jin and Qiang Meng (2010) “The process of information propagation in a traffic stream with a general vehicle headway: A revisit”, Transportation Research Part C: Emerging Technologies, 18(3), pp. 367–375. Available at: 10.1016/j.trc.2009.05.011.

research report

Role of Vehicle Technology on Use: Joint analysis of the choice of Plug-in Electric Vehicle ownership and miles traveled

Publication Date

September 1, 2023

Author(s)

Final Report

NCST-UCD-RR-23-30

Abstract

The increasing diversity of vehicle type holdings and growing demand for BEVs and PHEVs have serious policy implications for travel demand and air pollution. Consequently, it is important to accurately predict or estimate the preference for vehicle holdings of households as well as the vehicle miles traveled by vehicle body- and fuel-type to project future VMT changes and mobile source emission levels. Leveraging the 2019 California Vehicle Survey data, this report presents the application of a utility-based model for multiple discreteness that combines multiple vehicle types with usage in an integrated model, specifically the MDCEV model. The model results suggest the important effects of household demographics, residence location, and built environment factors on vehicle body type and powertrain choice and usage. Further the predictions associated with changes inbuilt environment factors like population density can inform the design of land-use and transportation policies to influence household vehicle holdings and usage that can in turn impact travel demand and air quality issues in California.View the NCST Project Webpage

Suggested Citation
Debapriya Chakraborty, David S. Bunch and David Brownstone (2023) Role of Vehicle Technology on Use: Joint analysis of the choice of Plug-in Electric Vehicle ownership and miles traveled. Final Report NCST-UCD-RR-23-30. Available at: https://escholarship.org/uc/item/3jj3v7pw (Accessed: October 11, 2023).

published journal article

Examining the joint effects of heatwaves, air pollution, and green space on the risk of preterm birth in California

Environmental Research Letters

Publication Date

October 1, 2020

Author(s)

Yi Sun, Sindana D. Ilango, Lara Schwarz, Qiong Wang, Jiu-Chiuan Chen, Jean M. Lawrence, Jun Wu, Tarik Benmarhnia

Abstract

Background. Exposure to high air temperature in late pregnancy is increasingly recognized as a risk factor for preterm birth (PTB). However, the combined effects of heatwaves with air pollution and green space are still unexplored. In the context of climate change, investigating the interaction between environmental factors and identifying communities at higher risk is important to better understand the etiological mechanisms and design targeted interventions towards certain women during pregnancy. Objectives. To examine the combined effects of heatwaves, air pollution and green space exposure on the risk of PTB. Methods. California birth certificate records for singleton births (2005–2013) were obtained. Residential zip code-specific daily temperature during the last week of gestation was used to create 12 definitions of heatwave with varying temperature thresholds and durations. We fit multi-level Cox proportional hazard models with time to PTB as the outcome and gestational week as the temporal unit. Relative risk due to interaction (RERI) was applied to estimate the additive interactive effect of air pollution and green space on the effect of heatwaves on PTB. Results. In total, 1 967 300 births were included in this study. For PM2.5, PM10 and O3, we found positive additive interactions (RERIs >0) between heatwaves and higher air pollution levels. Combined effects of heatwaves and green space indicated negative interactions (RERIs 0) for more intense heatwaves. Conclusion. This study found synergistic harmful effects for heatwaves with air pollution, and potential positive interactions with lack of green space on PTB. Implementing interventions, such as heat warning systems and behavioral changes, targeted toward pregnant women at risk for high air pollution and low green space exposures may optimize the benefits of reducing acute exposure to extreme heat before delivery.

Suggested Citation
Yi Sun, Sindana D. Ilango, Lara Schwarz, Qiong Wang, Jiu-Chiuan Chen, Jean M. Lawrence, Jun Wu and Tarik Benmarhnia (2020) “Examining the joint effects of heatwaves, air pollution, and green space on the risk of preterm birth in California”, Environmental Research Letters, 15(10), p. 104099. Available at: 10.1088/1748-9326/abb8a3.

published journal article

Macroscopic characteristics of lane-changing traffic

Transportation Research Record

Publication Date

January 1, 2010

Author(s)

Suggested Citation
Wen-Long Jin (2010) “Macroscopic characteristics of lane-changing traffic”, Transportation Research Record, 2188(1), pp. 55–63. Available at: 10.3141/2188-07.

working paper

Aggression on Roadways

Publication Date

June 1, 1989

Associated Project

Author(s)

Working Paper

UCI-ITS-WP-90-5, UCTC 16

Areas of Expertise

Abstract

Aggression and the automobile have had a long standing association, yet research on aggressive behavior has neglected the roadway context. This chapter reviews existing work which has included archival analysis, field interview studies, personality research, and field experiments. Among the recurrent themes have been the relationship between aggressivity in driving to accident liability and to violence in the larger social context. Validity issues in road aggression research are discussed, and a typology of roadway aggression is presented. The typology maps a range of contemporary forms, most of which have never been investigated scientifically and have received sparse academic attention otherwise, despite having high social and scientific relevance. Disinhibiting influences that heighten the probability of roadway aggression are discussed.

Suggested Citation
Raymond W. Novaco (1989) Aggression on Roadways. Working Paper UCI-ITS-WP-90-5, UCTC 16. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/3w38m6z8.

Phd Dissertation

Vehicle monitoring for traffic surveillance and performance using multi-sensor data fusion

Abstract

As traffic surveillance technology continues to advance, more complete and intelligent traffic information are available by processing detector data. The proposed dissertation aims to investigate thoroughly the use of recent detector technology in order to obtain useful freeway performance measurements by integrating multi sensor data fusion with a vehicle monitoring algorithm. Vehicle monitoring refers to the identification of the same vehicles at different locations. In this dissertation, two different state-of-the-art traffic detectors are introduced and the subsequent datasets are fused in order to obtain a more robust and effective traffic dataset for vehicle monitoring. Algorithm development for data fusion and real-time vehicle monitoring for traffic surveillance and performance, TRASURF (TRAffic SURveillance and performance) is developed, described, and investigated. Examinations of feature vector extraction from each advanced traffic sensor, fusion across multiple technologies, and analysis of sensor performance are major tasks prior to the development of the vehicle monitoring algorithm-TRASURF. A real dataset was used for single freeway section vehicle monitoring algorithm development and evaluation. Based on extensive field dataset analysis, PARAMICS (PARAllel MICroscopic Simulation), a microscopic traffic simulation model, was used for simulated fused data generation. Based on simulation dataset, multi-section vehicle monitoring algorithm, TRASURF, was tested and evaluated. The proposed simulation framework could be of great value for both testing and performance comparison of traffic surveillance algorithms. Developed vehicle monitoring system, TRASURF, will reconstruct individual vehicle trajectories, which will contribute to effective and efficient traffic surveillance. Furthermore, this enables the derivation of a variety of useful traffic information including network-wide traffic information such as path travel times and origin destination matrices. In addition to the multi-section TRASURF development, this dissertation also investigates and describes various applications of new detector data. Moreover, investigations on various applications of advanced detectors in transportation fields, and especially in single loop configuration, are also presented. The benefit of this approach can be explained by the fact that most of the freeway loop configurations in California, as well as in many other locations, adopt the single loop concept. Unavailable directly from conventional loop detectors, accurate traffic data extraction based on advanced loop detectors will make a vital contribution in many traffic operation and management fields.

Suggested Citation
Seri Park (2004) Vehicle monitoring for traffic surveillance and performance using multi-sensor data fusion. PhD Dissertation. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/1go3t9q/alma991035093146404701.

conference paper

Panel session - effective strategies to diversify engineering faculty

Proceedings. Frontiers in education. 36th annual conference

Publication Date

January 1, 2006

Author(s)

Lisa Frehill, Ann Gates, Steven Castillo, Emir Macari, Amelia Regan
Suggested Citation
Lisa Frehill, Ann Gates, Steven Castillo, Emir Macari and Amelia Regan (2006) “Panel session - effective strategies to diversify engineering faculty”, in Proceedings. Frontiers in education. 36th annual conference. IEEE, pp. 1–1. Available at: 10.1109/fie.2006.322453.