published journal article

Walkability, transit access, and traffic exposure for low-income residents with subsidized housing

American journal of public health

Publication Date

April 1, 2013

Author(s)

Doug Houston, Victoria Basolo, Dongwoo Yang

View published journal article

Abstract

This article describes a study undertaken to consider the factors of walkability, transit access, and traffic exposure for low-income residents living in subsidized housing. Within the context of smart growth development, the authors assessed the spatial distribution of subsidized housing units provided through 2 federally supported, low-income housing programs in Orange County, California: the Housing Choice Voucher Program and the Low Income Housing Tax Credit (LIHTC) program. They used data from multiple sources to examine land-use and health-related built environment factors and then evaluated the associations of those patterns with exposure to different traffic levels. Their results showed that subsidized projects or units in walkable, poorer neighborhoods were associated with lower traffic exposure; higher traffic exposure was associated with more transit service, a Hispanic majority, and mixed-use areas. They conclude that programs that adopt smart growth development goals can provide good access to amenities and encourage active travel and physical activity, and yet may not expose residents to higher traffic levels.

Suggested Citation

Douglas Houston, Victoria Basolo and Dongwoo Yang (2013) “Walkability, transit access, and traffic exposure for low-income residents with subsidized housing”, American journal of public health, 103(4), pp. 673–678. Available at: 10.2105/ajph.2012.300734.

conference paper

Proceedings of the 14Th world congress on intelligent transport systems (ITS 2007), held beijing, October 2007

Publication Date

January 1, 2007

Author(s)

Chih-Lin (Albert) Chung, Lianyu Chu, Will Recker

Abstract

Fast incident response and management are main tasks of Traffic Management Center (TMC) operators. Using the latest microscopic simulation modeling techniques, a TMC operator training system was developed and set up at California Advanced Transportation Management Systems (ATMS) Testbed of University of California, Irvine. The system is designed to duplicate the standardized TMC software systems and data feeds in a secure environment, where TMC operators can be trained to enrich their experiences and enhance their skills based on various incident scenarios. Since the completion of the prototype system, three training classes have been performed and satisfactory results have been obtained. For the covering abstract see ITRD E140665.

Suggested Citation

L. Chu and W. Recker (2007) “Proceedings of the 14Th world congress on intelligent transport systems (ITS 2007), held beijing, October 2007”. ITS America.

conference paper

Estimation of the time-dependency of values of travel time and its reliability from loop detector data

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

Publication Date

January 1, 2006

Author(s)

Will Recker, Henry Liu, Xiaozheng He

Abstract

Although the effects of travel time and its reliability have been addressed in a variety of papers concerning pricing policies, most of the existing research is based on the assumption that travelersâ?? preferences are static over a given time interval, such as the morning commuting period. Here, we relax this assumption, assuming rather that travelersâ?? tastes toward the travel time and its reliability vary with time, and examine their time-dependent effects on travelerâ??s route choice decisions. We adopt a mixed logit formulation of route choice behavior as a function of travel time, reliability, and cost. To uncover the values of travel time and its reliability, we introduce an alternative approach to the use of traveler surveys to estimate the model coefficients by determining the parameter set that produces the best match between the aggregated results from the travelersâ?? route choice model and the observed time-dependent traffic volume data from loop detectors. We apply the methodology to loop detector data obtained from the California State Route 91 value-pricing project, and use a genetic algorithm to identify the parameters. The time-dependent values of travel time and values of reliability for the morning commuting period are estimated and their implications on the toll pricing policy are discussed. The results indicate that, under the time-dependent formulation, travel-time savings may be more important than uncertain travel time when departure time is close to such time constraints as work-start time.

Suggested Citation

Wilfred W. Recker, Henry X. Liu and Xiaozheng He (2006) “Estimation of the time-dependency of values of travel time and its reliability from loop detector data”, in Proceedings of the 85th annual meeting of the transportation research board, p. 27p.

conference paper

Envy-free pricing for collaborative consumption of supply in transportation systems

Papers selected for the 22nd international symposium on transportation and traffic theory

Publication Date

January 1, 2017

Author(s)

Roger Lloret-Batlle, R. (Jay) Jayakrishnan

View conference paper

Abstract

Consumption of supply in transportation systems has generally always followed a First-Come-First-Served (FCFS) rule. This article proposes new control policies based on the concept of envy-freeness which outperform FCFS in both efficiency and fairness. We call an allocation envy-free when no agent feels any other agent’s allocation to be better than their own, at the current price. Envy-free allocations are thus considered fair. Several new contributions are made: we first present a conceptual theoretical supply demand framework which formally introduces the new supply paradigm. We propose and simulate a new problem, queue jumping operations on highways, in which vehicles can skip positions in a queue and compensate the overtaken vehicles with a payment. We present a new concept, dynamic envy-freeness, and provide a new envy ranking criterion, Constant Elasticity of Substitution Envy Intensity (CESEI) that is applied to PEXIC, an exchange-based traffic signal control scheme. (C) 2017 The Authors. Elsevier B.V. All rights reserved.

Suggested Citation

Roger Lloret-Batlle and R. Jayakrishnan (2017) “Envy-free pricing for collaborative consumption of supply in transportation systems”, in . Mahmassani, H and Nie, Y and Smilowitz, K (ed.) Papers selected for the 22nd international symposium on transportation and traffic theory. ELSEVIER SCIENCE BV (Transportation research procedia), pp. 772–789. Available at: 10.1016/j.trpro.2017.05.043.

published journal article

Continuous formulations and analytical properties of the link transmission model

Transportation Research Part B: Methodological

Publication Date

April 1, 2015

Author(s)

Wenlong Jin

View published journal article

Suggested Citation

Wen-Long Jin (2015) “Continuous formulations and analytical properties of the link transmission model”, Transportation Research Part B: Methodological, 74, pp. 88–103. Available at: 10.1016/j.trb.2014.12.006.

published journal article

Simultaneous estimation of states and parameters in Newell's simplified kinematic wave model with Eulerian and Lagrangian traffic data

Transportation Research Part B: Methodological

Publication Date

October 1, 2017

Author(s)

Zhe (Jared) Sun, Wenlong Jin, Stephen Ritchie

View published journal article

Suggested Citation

Zhe Sun, Wen-Long Jin and Stephen G. Ritchie (2017) “Simultaneous estimation of states and parameters in Newell's simplified kinematic wave model with Eulerian and Lagrangian traffic data”, Transportation Research Part B: Methodological, 104, pp. 106–122. Available at: 10.1016/j.trb.2017.06.012.

published journal article

Lane-level localization and mapping in GNSS-Challenged environments by fusing lidar data and cellular pseudoranges

IEEE Transactions on Intelligent Vehicles

Publication Date

March 1, 2019

Author(s)

Mahdi Maaref, Joe Khalife, Zaher Kassas

View published journal article

Suggested Citation

Mahdi Maaref, Joe Khalife and Zaher M. Kassas (2019) “Lane-level localization and mapping in GNSS-Challenged environments by fusing lidar data and cellular pseudoranges”, IEEE Transactions on Intelligent Vehicles, 4(1), pp. 73–89. Available at: 10.1109/tiv.2018.2886688.

research report

Large-Scale Traffic Simulation Through Distributed Computing of Paramics

Publication Date

October 1, 2004

Associated Project

Large-Scale Traffic Simulation Through Distributed Computing of Paramics

Author(s)

Henry Liu, Wenteng Ma, R. (Jay) Jayakrishnan, Will Recker

Final Report

UCB-ITS-PRR-2004-42

View research report

Abstract

Simulation modeling is an increasingly popular and effective tool for analyzing transportation problems, which are not amendable to study by other means. We examine the need for parallel or distributed simulation approaches from the need for computational speed-ups, availability of options towards that, and then at the need to distribute the effort to develop network simulation contexts and datasets. After an overview of the general techniques for the distributed discrete-event simulation and previous efforts on the distributed traffic simulation, we present the general architecture of the proposed distributed modeling framework. Two categories of modeling strategies, namely, light global control / independent subnets vs. heavy global control / coordinated subnets are described. We have implemented the distributed scheme of light global control / independent subnets and the implemented details, such as communication techniques and vehicle transferring across the boundary of two subnets are discussed. Unlike the previous studies using the dedicated high performance machines, our efforts are to utilize the low-cost networked PCs that are commonly available. By using the API supported by off-the-shelf Paramics software, we are able to distribute the computational load of microscopic simulation to multiple single-processor PCs without access the proprietary source codes of the simulation program. Performance testing and analysis of the implemented prototype demonstrate that the proposed framework is very promising.

Suggested Citation

Henry X. Liu, Wenteng Ma, R. Jayakrishnan and Will Recker (2004) Large-Scale Traffic Simulation Through Distributed Computing of Paramics. Final Report UCB-ITS-PRR-2004-42. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/4h1451bn.

published journal article

Feasibility study for SOFC-GT hybrid locomotive power: Part I. Development of a dynamic 3.5 MW SOFC-GT FORTRAN model

JOURNAL OF POWER SOURCES

Publication Date

January 1, 2012

Author(s)

Andrew S. Martinez, Jack Brouwer, Scott Samuelsen

View published journal article

Abstract

This work presents the development of a dynamic SOFC-GT hybrid system model applied to a long-haul freight locomotive in operation. Given the expectations of the rail industry, the model is used to develop a preliminary analysis of the proposed system’s operational capability on conventional diesel fuel as well as natural gas and hydrogen as potential fuels in the future. It is found that operation of the system on all three of these fuels is feasible with favorable efficiencies and reasonable dynamic response. The use of diesel fuel reformate in the SOFC presents a challenge to the electrochemistry, especially as it relates to control and optimization of the fuel utilization in the anode compartment. This is found to arise from the large amount of carbon monoxide in diesel reformate that is fed to the fuel cell, limiting the maximum fuel utilization possible. This presents an opportunity for further investigations into carbon monoxide electrochemical oxidation and/or system integration studies where the efficiency of the fuel reformer can be balanced against the needs of the SOFC. (C) 2012 Elsevier B.V. All rights reserved.

Suggested Citation

Andrew S. Martinez, Jacob Brouwer and G. Scott Samuelsen (2012) “Feasibility study for SOFC-GT hybrid locomotive power: Part I. Development of a dynamic 3.5 MW SOFC-GT FORTRAN model”, JOURNAL OF POWER SOURCES, 213, pp. 203–217. Available at: 10.1016/j.jpowsour.2012.04.024.

research report

Transportation financing opportunities for the state of California

Publication Date

October 1, 2006

Author(s)

Asha Weinstein, Jennifer Dill, Todd Goldman, John Hall, Franziska Holtzman, Joe Recker

Abstract

Available funding for transportation in California is expected to decline significantly over the next 15 years if the current transportation finance system remains unchanged. This report presents an analysis of a range of alternative sources of revenue, as well as different finance options. The research is based upon reviews of existing literature, interviews with key stakeholders, analyses of revenue trends, fuel tax rates and trends, statewide ballot measures, and two statewide phone surveys. The facility-based sources considered were toll roads and lanes, truck-only toll lanes, privatized rest areas, and public-private partnerships (PPPs). The taxes and fees evaluated were increasing fuel taxes by a fixed amount, indexing fuel taxes to inflation, mileage-based fees, vehicle registration fees, vehicle license fees, weight-mile taxes for trucks, a statewide sales tax, and state general fund revenues allocated either for current expenditures or to pay off general obligation bonds. Each of the revenue and finance options was evaluated according to five criteria: (1) revenue generation; (2) ease of implementation; (3) transportation system performance; (4) equity; and (5) political feasibility.

Suggested Citation

Asha Weinstein, Jennifer Dill, Todd Goldman, John Hall, Franziska Holtzman and Joe Recker (2006) Transportation financing opportunities for the state of California, p. 234p.