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The exposition light rail line study: A before and after study of the impact of new light rail transit service
Publication Date
Author(s)
Abstract
A detailed study shows changes in travel behavior around new Exposition (Expo) Line light rail stations in Los Angeles. The Expo Line runs 8.7 miles from downtown Los Angeles. The six western-most stations along the Expo Line comprise the experimental neighborhoods, and similar control group neighborhoods were chosen nearby. This research project enrolled experimental households, within œ mile of a new Expo Line station, and control households, living beyond œ mile from the station. In fall of 2011, those households were asked to track their travel for seven days. In approximately half of the households, an adult also carried a GPS device and an accelerometer, to measure travel and physical activity. Evidence shows that the Expo Line is associated with large reductions in VMT, some increase in rail transit ridership, changes in physical activity, and large reductions in GHG emissions among households living within œ mile of a station. The research design, using a control group to account for factors other than the rail investment, allows causal inferences to be made more strongly than is often the case in social scientific research. Viewed from the perspective of the greater Los Angeles region, these impacts will be small, but they are large in the neighborhoods surrounding the Expo Line.
Suggested Citation
Marlon G. Boarnet, Andy Hong, Jeongwoo Lee, Xize Wang, Weijie Wang, Doug Houston and Steven Spears (2013) The exposition light rail line study: A before and after study of the impact of new light rail transit service, p. vii, 64p.published journal article
Method for creating a real-time distributed travel history database. Persistent Traffic Cookies Project
Transportation Research Record
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Author(s)
Suggested Citation
James E. Marca, Craig R. Rindt and R. Jayakrishnan (2006) “Method for creating a real-time distributed travel history database. Persistent Traffic Cookies Project”, Transportation Research Record, 1972(1), pp. 69–77. Available at: 10.1177/0361198106197200109.published journal article
Association between local traffic-generated air pollution and preeclampsia and preterm delivery in the south coast air basin of California
Environmental Health Perspectives
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Author(s)
Abstract
Background: Preeclampsia is a major complication of pregnancy that can lead to substantial maternal and perinatal morbidity, mortality, and preterm birth. Increasing evidence suggests that air pollution adversely affects pregnancy outcomes. Yet few studies have examined how local traffic generated emissions affect preeclampsia in addition to preterm birth. Objectives: We examined effects of residential exposure to local traffic-generated air pollution on preeclampsia and preterm delivery (PTD). Methods: We identified 81,186 singleton birth records from four hospitals (1997-2006) in Los Angeles and Orange Counties, California (USA). We used a line source dispersion model (CALINE4) to estimate individual exposure to local traffic-generated nitrogen oxides (NO_x ) and particulate matter ¡ 2.5 𝜇m in aerodynamic diameter (PM_2.5 ) across the entire pregnancy. We used logistic regression to estimate effects of air pollution exposures on preeclampsia. PRD (gestational age ¡ 37 weeks), moderate PTD (MPTD; gestational age ¡ 35 weeks), and very PTD (VPTD; gestational age ¡ 30 weeks). Results: We observed elevated risks for preeclampsia and preterm birth from maternal exposure to local traffic-generated NO_x and PM_2.5 . The risk of preeclampsia increased 33
Suggested Citation
Jun Wu, Cizao Ren, Ralph J. Delfino, Judith Chung, Michelle Wilhelm and Beate Ritz (2009) “Association between local traffic-generated air pollution and preeclampsia and preterm delivery in the south coast air basin of California”, Environmental Health Perspectives, 117(11), pp. 1773–1779. Available at: 10.1289/ehp.0800334.working paper
Impacts of Motor Vehicle Operation on Water Quality in the United States - Clean-up Costs and Policies
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Areas of Expertise
Abstract
This paper investigates the costs of controlling some of the environmental impacts of motor vehicle transportation on groundwater and on surface waters. We estimate that annualized costs of cleaning-up leaking underground storage tanks range from $0.8 billion to $2.1 billion per year over ten years. Annualized costs of controlling highway runoff from principal arterials in the US are much larger: they range from $2.9 billion to $15.6 billion per year over 20 years (1.6% to 8.3% of annualized highway transportation expenditures.) Some causes of non-point source pollution were unintentionally created by regulations or could be addressed by simple design changes of motor vehicles. A review of applicable measures suggests that effective policies should combine economic incentives, information campaigns, and enforcement, coupled with preventive environmental measures. In general, preventing water pollution from motor vehicles would be much cheaper than cleaning it up.
working paper
Regional Impacts of Neotraditional Neighborhood Development
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Associated Project
Author(s)
Working Paper
Areas of Expertise
Abstract
In recent years, the Neotraditional Neighborhood Development (NTND) land use planning movement, which is also known as “Traditional Neighborhood Development”, has gained increasing attention from planning, engineering, and development professionals. This increased popularity stems from the recognition that the concepts embodied in NTND address many of the most pressing social and economic problems in urban areas, including growth management, traffic congestion, open space preservation, and housing shortages. Through basic changes in land use patterns, street geometries, and network design, NTND attempts to improve accessibility via increased efficiency in travel/activity patterns. Improvements in network connectivity are coupled with lower speeds resulting in comparable travel times but reduced vehicle miles traveled, less congestion, and improved air quality.
Suggested Citation
Michael G. McNally (1993) Regional Impacts of Neotraditional Neighborhood Development. Working Paper UCI-ITS-WP-93-8, UCTC 172. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/5nq0f552.published journal article
HyperDetect: A Real-Time Hyperdimensional Solution for Intrusion Detection in IoT Networks
IEEE Internet of Things Journal
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Author(s)
Abstract
Network-based security has emerged as an increasingly critical challenge in the domain of the Internet of Things (IoT). A number of network intrusion detection systems (NIDS), typically relying on sophisticated machine learning (ML) algorithms, have been proposed to monitor network traffic and detect malicious activity. However, these NIDS designs require extensive memory and computational power, exceeding the capability of today’s IoT devices, and often fail to provide timely detection of network attacks. To tackle this issue, we propose mathsf HyperDetect , the first attempt at NIDS modeling that leverages the highly efficient and parallel operations of brain-inspired hyperdimensional computing (HDC). Our innovative model updating method effectively mitigates model saturation and significantly reduces the number of retraining iterations needed to reach convergence. Additionally, we employ a novel dynamic encoding technique to regenerate insignificant dimensions, considerably lowering the dimensionalities required to achieve high-quality performance and further accelerating the learning process. mathsf HyperDetect delivers on average 5.02times faster training and 31.83times faster inference compared to state-of-the-art (SOTA) learning approaches on a wide range of network intrusion classification tasks. We also extensively evaluate mathsf HyperDetect on embedded hardware to demonstrate its low-latency and resource-efficient characteristics.
Suggested Citation
Junyao Wang, Haocheng Xu, Yonatan Gizachew Achamyeleh, Sitao Huang and Mohammad Abdullah Al Faruque (2024) “HyperDetect: A Real-Time Hyperdimensional Solution for Intrusion Detection in IoT Networks”, IEEE Internet of Things Journal, 11(8), pp. 14844–14856. Available at: 10.1109/JIOT.2023.3345279.published journal article
Policy Implications of Incorporating Hybrid Vehicles into High-Occupancy Vehicle Lanes
Journal of Transportation Systems Engineering and Information Technology
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Author(s)
Suggested Citation
KS Nesamani, Lianyu Chu and Will Recker (2010) “Policy Implications of Incorporating Hybrid Vehicles into High-Occupancy Vehicle Lanes”, Journal of Transportation Systems Engineering and Information Technology, 10(2), pp. 30–41. Available at: 10.1016/s1570-6672(09)60031-3.working paper
A Model of Household Interactions in Activity Patterns
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Author(s)
Working Paper
Abstract
Time is an important aspect of the activity patterns of individuals. An activity pattern can be described by means of a time-space diagram (Hagerstrand, 1970), that describes, for each moment within a given time interval, the location and type of activity of an individual. These time-space patterns are the result of various decisions and events experienced by that individual. In this paper, we will focus on the time dimensions of the space-time activity patterns of individuals. More specifically, we will focus attention on the allocation of time to a number of out-of-home activities. Other aspects, such as the timing and scheduling of activities are outside the scope of this paper.
Suggested Citation
Leo J.G. van Wissen (1989) A Model of Household Interactions in Activity Patterns. Working Paper UCI-ITS-WP-89-9, UCI-ITS-AS-WP-89-1, UCTC 15. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/1j36k4h3.conference paper