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Full-Text Articles in Transportation

Understanding Multi-Homing And Switching By Platform Drivers, Xiaotong Guo, Andreas Haupt, Hai Wang, Rida Qadri, Jinhua Zhao Sep 2023

Understanding Multi-Homing And Switching By Platform Drivers, Xiaotong Guo, Andreas Haupt, Hai Wang, Rida Qadri, Jinhua Zhao

Research Collection School Of Computing and Information Systems

Freelance drivers in the shared mobility market frequently switch or work for multiple platforms, affecting driver labor supply. Due to the importance of driver labor supply for the shared mobility market, understanding drivers’ switching and multi-homing behavior is vital to managing service quality on – and effective regulation of – mobility platforms. However, a lack of individual-level data on driver behavior has thus far impeded a deeper understanding. This paper taxonomizes and estimates perceived switching and multi-homing frictions on mobility platforms. Based on a structural model of driver labor supply, we estimate switching and multi-homing costs in a platform duopoly …


Attention And Task Engagement During Automated Driving, James Richard Unverricht Aug 2023

Attention And Task Engagement During Automated Driving, James Richard Unverricht

Psychology Theses & Dissertations

Many young drivers suffer fatal crashes each year in the United States at a rate approximately three times greater than more experienced drivers. Automated driving systems may serve to mitigate young drivers high crash rates but remain underexplored in research. This dissertation project examined the effects of levels of automation and interestingness of auditory clips on latent hazard anticipation in young drivers during simulated driving. Participants drove a vehicle at varying levels of vehicle automation (SAE Level 0, 2, or 3) in simulated scenarios, each containing a latent hazard event during which a boring, neutral, or interesting auditory clip was …


Fiber-Based Seismic Damage And Collapse Assessment Of Reinforced Concrete Single-Column Pier-Supported Bridges Using Damage Indices, Yu-Fu Ko, Jessica Gonzalez Aug 2023

Fiber-Based Seismic Damage And Collapse Assessment Of Reinforced Concrete Single-Column Pier-Supported Bridges Using Damage Indices, Yu-Fu Ko, Jessica Gonzalez

Mineta Transportation Institute

Near-fault earthquakes can have major effects on transportation systems due to the structural damage they impose on bridges. Therefore, it is imperative to assess the seismic damage of bridges appropriately, and this research focuses on reinforced concrete (RC) bridges. This research advances the seismic performance assessment of RC single-column pier-supported bridges with flexural failure under near-fault ground motion by use of ductility coefficients and damage indices. The methodology included modeling fiber-based nonlinear beam-column elements to simulate the damage development process of RC bridge piers under earthquake loadings, considering the global buckling of longitudinal steel bars, examining the cracking and spalling …


System-Of-Systems Integration For Civil Infrastructures Resiliency Toward Multihazard Events, Vahid Balali Aug 2023

System-Of-Systems Integration For Civil Infrastructures Resiliency Toward Multihazard Events, Vahid Balali

Mineta Transportation Institute

Civil infrastructure systems—facilities that supply principal services, such as electricity, water, transportation, etc., to a community—are the backbone of modern society. These systems are frequently subject to multi-hazard events, such as earthquakes. The poor resiliency of these infrastructures results in many human casualties and significant economic losses every year. An outline of a holistic view that considers how different civil infrastructure systems operate independently and how they interact and communicate with each other is required to have a resilient infrastructure system. More specifically a systems engineering approach is required to enable infrastructure to remain resilient in the case of extreme …


An Advanced Simulation Architecture For Testing Autonomous And Connected Vehicles Enabled By Virtual Reality, Defu Cui Aug 2023

An Advanced Simulation Architecture For Testing Autonomous And Connected Vehicles Enabled By Virtual Reality, Defu Cui

Electrical & Computer Engineering Theses & Dissertations

With the advancement of intelligent transportation systems, autonomous driving and connected driving are seen as potential solutions to alleviate traffic congestion, enhance traffic safety, and improve efficiency. Extensive testing and validation of autonomous vehicles (AVs) and connected vehicles (CVs) including connected autonomous vehicles are crucial to ensure their safety and reliability. However, testing and validating AVs and CVs on public roads faces challenges such as high costs, inadequate support from transportation infrastructure with communication technologies, and safety concerns, among others. Simulations have become essential tools for testing autonomous driving and connected driving. As mixed traffic involves multiple domains including traffic …


Extending The Service-Life Of Bridges Using Sustainable And Resilient Abutment Systems: An Experimental Approach To Electrochemical Characterization Of Lightweight Mechanically Stabilized Earth, Fariborz M. Tehrani, Kenneth L. Fishman, Farmehr M. Dehkordi Jul 2023

Extending The Service-Life Of Bridges Using Sustainable And Resilient Abutment Systems: An Experimental Approach To Electrochemical Characterization Of Lightweight Mechanically Stabilized Earth, Fariborz M. Tehrani, Kenneth L. Fishman, Farmehr M. Dehkordi

Mineta Transportation Institute

Bridges are critical components of transportation infrastructure. This research addresses the need to extend the service life of bridges by improving the safety and reliability of bridge abutments and reducing their life-cycle cost and footprints. Mechanically stabilized earth (MSE) is a known strategy to enhance the economy and performance of bridge abutments. In addition, the application of rotary-kiln-manufactured lightweight aggregate backfills improves the performance of MSE bridge abutments with a leaner structural system. Such improvements include a reduction of structural demands due to a lower density, free drainage of granular materials, a high internal friction angle, less settlement with no …


Electrical Vehicle Charging Infrastructure Design And Operations, Yu Yang, Hen-Geul Yeh Jul 2023

Electrical Vehicle Charging Infrastructure Design And Operations, Yu Yang, Hen-Geul Yeh

Mineta Transportation Institute

California aims to achieve five million zero-emission vehicles (ZEVs) on the road by 2030 and 250,000 electrical vehicle (EV) charging stations by 2025. To reduce barriers in this process, the research team developed a simulation-based system for EV charging infrastructure design and operations. The increasing power demand due to the growing EV market requires advanced charging infrastructures and operating strategies. This study will deliver two modules in charging station design and operations, including a vehicle charging schedule and an infrastructure planning module for the solar-powered charging station. The objectives are to increase customers’ satisfaction, reduce the power grid burden, and …


Imitation Improvement Learning For Large-Scale Capacitated Vehicle Routing Problems, The Viet Bui, Tien Mai Jul 2023

Imitation Improvement Learning For Large-Scale Capacitated Vehicle Routing Problems, The Viet Bui, Tien Mai

Research Collection School Of Computing and Information Systems

Recent works using deep reinforcement learning (RL) to solve routing problems such as the capacitated vehicle routing problem (CVRP) have focused on improvement learning-based methods, which involve improving a given solution until it becomes near-optimal. Although adequate solutions can be achieved for small problem instances, their efficiency degrades for large-scale ones. In this work, we propose a newimprovement learning-based framework based on imitation learning where classical heuristics serve as experts to encourage the policy model to mimic and produce similar or better solutions. Moreover, to improve scalability, we propose Clockwise Clustering, a novel augmented framework for decomposing large-scale CVRP into …


Estimation Of Recursive Route Choice Models With Incomplete Trip Observations, Tien Mai, The Viet Bui, Quoc Phong Nguyen, Tho V. Le Jul 2023

Estimation Of Recursive Route Choice Models With Incomplete Trip Observations, Tien Mai, The Viet Bui, Quoc Phong Nguyen, Tho V. Le

Research Collection School Of Computing and Information Systems

This work concerns the estimation of recursive route choice models in the situation that the trip observations are incomplete, i.e., there are unconnected links (or nodes) in the observations. A direct approach to handle this issue could be intractable because enumerating all paths between unconnected links (or nodes) in a real network is typically not possible. We exploit an expectation–maximization (EM) method that allows dealing with the missing-data issue by alternatively performing two steps of sampling the missing segments in the observations and solving maximum likelihood estimation problems. Moreover, observing that the EM method could be expensive, we propose a …


Optimization Of Station-Skip In A Cyclic Express Subway Service, Jingfeng Yang, Hai Wang, Jiangang Jin Jun 2023

Optimization Of Station-Skip In A Cyclic Express Subway Service, Jingfeng Yang, Hai Wang, Jiangang Jin

Research Collection School Of Computing and Information Systems

With rapid population growth and increasing demand for urban mobility, metropolitan areas such as Singapore, Tokyo, and Shanghai are increasingly dependent on public transport systems. Various strategies are proposed to improve the service quality and capacity of bus and subway systems. Express trains—i.e., trains that skip certain stations—are commonly used because they can travel at higher speeds, potentially reduce travel time, and serve more passengers. In this paper, we study cyclic express subway service (CESS), in which express trains provide routine transport service with cyclic (periodic) station-skip patterns that can be used in daily service. We propose an exact Mixed …


Pavement Condition Survey Using Drone Technology, Lerose Lane, Dingxin Cheng Jun 2023

Pavement Condition Survey Using Drone Technology, Lerose Lane, Dingxin Cheng

Mineta Transportation Institute

Timely repairs of pavement defects are essential in protecting both public road and highway systems. Identification of pavement distresses is necessary for planning pavement repairs. This has previously been performed by engineers surveying the roadways visually in the field. As drone usage has progressed, it has become clear that drones are a valuable tool to enhance visual documentation, improve project communication, and provide various data for processing. The use of drone technology has improved both the speed and accuracy of capturing data. Available software has allowed the data to be processed and analyzed in an office environment. This report summarizes …


Historic Downtown Streetscape Plan Price City, Utah, Patricia Beckert May 2023

Historic Downtown Streetscape Plan Price City, Utah, Patricia Beckert

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The idea of a small-town Main Street has profound meaning within the American culture that has prevailed for the past two centuries. Historically, Main Street serves as the beating heart of a community, a place where economic, social, cultural, and civic activities are centered (Francaviglia, 1996; Main Street America, n.d.). Since the beginning of the 19th century, many factors have led to the decline of Main Streets, and despite a variety of efforts from different stakeholders, that decline has only intensified in recent decades (Isenberg, 2008; Orvell, 2014 Howard, 2015). In 1980, after a three-year project conducted by the National …


Electric Vehicle Routing Problem – Models And Algorithms, Hesamoddin Tahami May 2023

Electric Vehicle Routing Problem – Models And Algorithms, Hesamoddin Tahami

Engineering Management & Systems Engineering Theses & Dissertations

The transportation sector is a major greenhouse gas emitter that is heavily regulated to reduce its dependence on oil. These regulations along with the growing customer awareness of global warming have led to the investigation of new transportation problems that consider using eco-friendly vehicle fleets. Promising alternatives to traditional fleets include alternative fuel vehicles (AFVs) and electric vehicles (EVs). These twenty-first-century vehicles offer an appealing advantage of consistently reducing their environmental impact, but due to the current technology, they exhibit bothersome limitations. The short driving range along with limited charging infrastructure may consequently cause issues related to range anxiety, i.e., …


Editorial: Innovative Shared Transportation, Marco Nie, Hai Wang, Wai Yuen Szeto May 2023

Editorial: Innovative Shared Transportation, Marco Nie, Hai Wang, Wai Yuen Szeto

Research Collection School Of Computing and Information Systems

Recent technological developments—mobile computing, autonomous driving, alternative fuel vehicles, and blockchain, to name a few—have enabled numerous innovations in mobility, transportation, and logistics services. They offer unprecedented opportunities to transform conventional transportation systems, for both personal travel and freight logistics, with novel solutions. Of these solutions, those built on the emerging concept of shared economy, such as Uber, Didi, and Cargostream, have received much attention recently. The rapidly expanding scope of shared transportation services now includes ride-sourcing, ridesharing, car sharing, hitch service, flexible paratransit, shared freight delivery, shared logistics, bike sharing, shared last-mile service, parking space sharing, and so on.


Smart Transportation In Small- And Medium-Sized Cities In Central California, Hongwei Dong May 2023

Smart Transportation In Small- And Medium-Sized Cities In Central California, Hongwei Dong

Mineta Transportation Institute

The research on smart transportation in the United States has centered on large metropolitan areas. The adoption of smart transportation technologies in small-and medium-sized cities outside of large metropolitan areas is less studied and understood. This study examined the adoption of smart transportation technologies in small-and medium-sized cities in Central California. The analysis was based on the online survey responses from 29 transportation officials and professionals who worked for 18 municipal government departments and six metropolitan planning organizations (MPOs) in Central California as well as in depth semi-structured interviews with seven of them. The study showed that smart transportation in …


Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures, Pitiporn Asvapathanagul, Simone Galano, Andrea Calabrese, Mehran Rahmani, Maggie Ly, Daniela Flores, Michael Hernandez, Nicholas Banuelos May 2023

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures, Pitiporn Asvapathanagul, Simone Galano, Andrea Calabrese, Mehran Rahmani, Maggie Ly, Daniela Flores, Michael Hernandez, Nicholas Banuelos

Mineta Transportation Institute

Although concrete is the most widely used building material in the world, its limited tensile strength makes cracking a common phenomenon in concrete elements. This study investigates the potential of autonomous self-healing as an eco-friendly and lowcost method to increase the durability of concrete. The crack-healing potential of different types of high-alkaline-tolerant bacteria or calcite-precipitation microorganisms is investigated. High-alkaline-tolerant bacteria and calcite-precipitation microorganisms were used to retrofit lab-fractured concrete samples. The samples healed with each of these bacteria groups were cast and tested under compressive load up to failure to measure the compressive strength of the concrete samples. The outcomes …


Preconstruction Support Cost Hours Estimating On Caltrans Pavement Rehabilitation Projects, Nigel Blampied, Tariq Shehab, Elhami Nasr, Laxmi Sindhu Samudrala May 2023

Preconstruction Support Cost Hours Estimating On Caltrans Pavement Rehabilitation Projects, Nigel Blampied, Tariq Shehab, Elhami Nasr, Laxmi Sindhu Samudrala

Mineta Transportation Institute

Because the construction phase accounts for the majority of project costs for pavement rehabilitation projects, most research on infrastructure project cost estimating focuses on that phase, rather than on the preconstruction phases. Nevertheless, costs incurred prior to construction, referred to in this report as "preconstruction costs" are significant and worthy of consideration (See Section 2.1 of the report for a more detailed and precise definition of preconstruction). In the 20202021 fiscal year, for instance, the California Department of Transportation (Caltrans) spent more than $169 million on preconstruction work for pavement rehabilitation projects. This report presents the results of a study …


Modeling And Evaluating Alternatives To Enhance Access To An Airport And Meet Future Expansion Needs, Srinivas S. Pulugurtha, Abimbola Ogungbire, Chirag Akbari Apr 2023

Modeling And Evaluating Alternatives To Enhance Access To An Airport And Meet Future Expansion Needs, Srinivas S. Pulugurtha, Abimbola Ogungbire, Chirag Akbari

Mineta Transportation Institute

The continued growth of air travel calls for the incessant construction effort at many airports and their surroundings. Thus, there is a need to determine how airports can better manage existing infrastructure to accommodate this growth. This study, therefore, focuses on (1) investigating how changes in transportation infrastructure have affected travel time reliability (TTR) of the surrounding road network within the airport vicinity over time, and, (2) exploring selected unconventional intersection designs and proposing new inbound/outbound access routes from the nearby major roads to the airport. The efficiency of road networks that surrounds large airports is discussed using Charlotte Douglas …


Using Thermal Remote Sensing To Quantify Impact Of Traffic On Urban Heat Islands During Covid, My-Thu Tran, Bo Yang Apr 2023

Using Thermal Remote Sensing To Quantify Impact Of Traffic On Urban Heat Islands During Covid, My-Thu Tran, Bo Yang

Mineta Transportation Institute

A three-month lockdown in the U.S. at the beginning of the COVID-19 outbreak in 2020 greatly reduced the traffic volume in many cities, especially large metropolitan areas such as the San Francisco Bay Area. This research explores the impact of transportation on climate change by using remote sensing technology and statistical analysis during the COVID-19 lockdown. Using thermal satellite data, this research measures the intensity of the urban heat island, the main driver for climate change during the urbanization process. The research team acquired morning and afternoon MODIS data in the same periods in 2019 before the pandemic and 2020 …


Planning For Pedestrians And Bicyclists During Construction Projects, John Habermann, P.E. Mar 2023

Planning For Pedestrians And Bicyclists During Construction Projects, John Habermann, P.E.

Purdue Road School

This session will explore how the Texas Department of Transportation Waco District addressed pedestrian/bicyclist safety and mobility during a multi-year construction project along I-35. This presentation will demonstrate the value of online tools, field implementations, and data collection. Attendees will learn the value of assembling a stakeholder steering committee; counting pedestrian and bicyclists before, during, and after construction; effectively using pavement clings; and using a webpage dedicated to pedestrian/bicyclist updates.


See A Sign? Make A Call, John Habermann, P.E. Mar 2023

See A Sign? Make A Call, John Habermann, P.E.

Purdue Road School

DOT staff and technology resources have the proven potential to help combat human trafficking if DOT employees know the indicators of human trafficking and how to cooperate with requests from agencies for information that can be derived from DOT assets. The Texas A&M Transportation Institute, NCHRP, and the Heart of Texas Human Trafficking Coalition will discuss the intersection of human trafficking with the transportation sector. Attendees will also learn the main components of human trafficking, the basic signs of human trafficking on DOT facilities, and resources to use in their own states.


Introduction To The Special Issue On Innovation In Transportation-Enabled Urban Services, Part 1, Niels Agatz, Soo-Haeng Cho, Hai Wang, Saif Benjaafar Mar 2023

Introduction To The Special Issue On Innovation In Transportation-Enabled Urban Services, Part 1, Niels Agatz, Soo-Haeng Cho, Hai Wang, Saif Benjaafar

Research Collection School Of Computing and Information Systems

Rapid developments in city infrastructure and technol-ogies are creating numerous opportunities and inspiring innovative and emerging urban services. Among these innovations, complex systems of urban transportation and logistics have embraced advances and have been reshaped significantly. They enable innovative new urban services, which are now booming and changing everyday life for urban residents.This special issue of Service Science explores perspectives on innovation in transportation-enabled urban services. We hope that the special issue will enhance the understanding of the planning, operation, and management of such services. Contributions are expected to demonstrate rigorous model development, economic/ econometric analysis, and decision-making tools based …


Evaluating Automated Truck Platoon (Atp) Deployment For The Los Angeles–Inland Empire Trade Corridor Enhancement, Shailesh Chandra, Aastha Chaudhary, Prakhar Srivastava, Jose Torres-Aguilera Mar 2023

Evaluating Automated Truck Platoon (Atp) Deployment For The Los Angeles–Inland Empire Trade Corridor Enhancement, Shailesh Chandra, Aastha Chaudhary, Prakhar Srivastava, Jose Torres-Aguilera

Mineta Transportation Institute

The California Freight Mobility Plan 2020 lists the Los Angeles-Inland Empire trade corridor region as a prominent industrial hub experiencing an increase in freight flows. The California Freight Mobility Plan also regards automated truck platoon (ATP) as an emerging opportunity to minimize congestion on the trade corridor routes. Percentage change in accessibility from 2022 (“without” ATP) to 2040 (“with” ATP) is calculated for the eighteen industry sectors of the Los Angeles-Inland Empire trade corridor. The application of the accessibility formulation was carried out with data on travel time from I-710 and I-10 within Los Angeles County. The findings suggest that …


Evaluation, Comparison, And Improvement Recommendations For Caltrans Financial Programming Processes And Tools, Wenbin Wei, Nigel Blampied, Raajmaathangi Sreevijay Feb 2023

Evaluation, Comparison, And Improvement Recommendations For Caltrans Financial Programming Processes And Tools, Wenbin Wei, Nigel Blampied, Raajmaathangi Sreevijay

Mineta Transportation Institute

The California Transportation Improvement Program System (CTIPS) is the main tool used by Caltrans’ Division of Financial Programming to support the business of transportation programming. It is a multi-agency joint-use project programming database system applied to develop and manage various state and federal transportation programming documents. The goal of this project is to evaluate CTIPS and explore various new options that will maintain the current functionality of CTIPS, meet legislative guidelines for ADA compliance, ensure security of the system, and have sufficient scalability and capabilities for integration with other systems in the future. The research is based on the review …


A Diversity-Enhanced Memetic Algorithm For Solving Electric Vehicle Routing Problems With Time Windows And Mixed Backhauls, Jianhua Xiao, Jingguo Du, Zhiguang Cao, Xingyi Zhang, Yunyun Niu Jan 2023

A Diversity-Enhanced Memetic Algorithm For Solving Electric Vehicle Routing Problems With Time Windows And Mixed Backhauls, Jianhua Xiao, Jingguo Du, Zhiguang Cao, Xingyi Zhang, Yunyun Niu

Research Collection School Of Computing and Information Systems

The electric vehicle routing problem (EVRP) has been studied increasingly because of environmental concerns. However, existing studies on the EVRP mainly focus on time windows and sole linehaul customers, which might not be practical as backhaul customers are also ubiquitous in reality. In this study, we investigate an EVRP with time windows and mixed backhauls (EVRPTWMB), where both linehaul and backhaul customers exist and can be served in any order. To address this challenging problem, we propose a diversity-enhanced memetic algorithm (DEMA) that integrates three types of novel operators, including genetic operators based on adaptive selection mechanism, a selection operator …


Improving Safety Service Patrol Performance, Mecit Cetin, Hong Yang, Kun Xie, Sherif Ishak, Guocong Zhai, Junqing Wang, Giridhar Kattepogu Jan 2023

Improving Safety Service Patrol Performance, Mecit Cetin, Hong Yang, Kun Xie, Sherif Ishak, Guocong Zhai, Junqing Wang, Giridhar Kattepogu

Civil & Environmental Engineering Faculty Publications

Safety Service Patrols (SSPs) provide motorists with assistance free of charge on most freeways and some key primary roads in Virginia. This research project is focused on developing a tool to help the Virginia Department of Transportation (VDOT) optimize SSP routes and schedules (hereafter called SSP-OPT). The computational tool, SSP-OPT, takes readily available data (e.g., corridor and segment lengths, turnaround points, average annual daily traffic) and outputs potential SSP configurations that meet the desired criteria and produce the best possible performance metrics for a given corridor. At a high level, the main components of the developed tool include capabilities to: …


Evaluation Of Nanoclay Additives For Improving Resistance To Moisture Damage In Hot Mix Asphalt (Hma), Amro El Badawy, Ashraf Rahim Jan 2023

Evaluation Of Nanoclay Additives For Improving Resistance To Moisture Damage In Hot Mix Asphalt (Hma), Amro El Badawy, Ashraf Rahim

Mineta Transportation Institute

Transportation has an enormous impact on the U.S. economy and on the lives of all Americans. Many modes of transportation rely on pavement, but pavement conditions deteriorate over time because of the combined effects of traffic and climate. Exposure to moisture often causes premature failure of asphalt pavements as it reduces the stiffness of the asphalt and enables stripping of the asphalt from the aggregate. This research evaluates the effectiveness of clay nanomaterials (i.e., nanoclays) in improving the resistance of hot mix asphalt (HMA) to moisture damage and compares the enhancement results to anti-stripping additives commonly used in pavement construction. …


Coordinating Multi-Party Vehicle Routing With Location Congestion Via Iterative Best Response, Waldy Joe, Hoong Chuin Lau Jan 2023

Coordinating Multi-Party Vehicle Routing With Location Congestion Via Iterative Best Response, Waldy Joe, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

This work is motivated by a real-world problem of coordinating B2B pickup-delivery operations to shopping malls involving multiple non-collaborative logistics service providers (LSPs) in a congested city where space is scarce. This problem can be categorized as a vehicle routing problem with pickup and delivery, time windows and location congestion with multiple LSPs (or ML-VRPLC in short), and we propose a scalable, decentralized, coordinated planning approach via iterative best response. We formulate the problem as a strategic game where each LSP is a self-interested agent but is willing to participate in a coordinated planning as long as there are sufficient …


Are Ride-Hailing Services Safer Than Taxis? A Multivariate Spatial Approach With Accomodation Of Exposure Uncertainty, Guocong Zhai, Kun Xie, Hong Yang, Di Yang Jan 2023

Are Ride-Hailing Services Safer Than Taxis? A Multivariate Spatial Approach With Accomodation Of Exposure Uncertainty, Guocong Zhai, Kun Xie, Hong Yang, Di Yang

Civil & Environmental Engineering Faculty Publications

Despite many research efforts on ride-hailing services and taxis, limited studies have compared the safety performance of the two modes. A major challenge is the need for reliable mode-specific exposure data to model their safety outcomes. Moreover, crash frequencies of the two modes by injury severities tend to be spatially and inherently correlated. To fully address these issues, this study proposes a novel multivariate conditional autoregressive model considering measurement errors in mode-specific exposures (MVCARME). More specially, a classical measurement error structure is used to accommodate the uncertainty of mode-specific exposures estimated, and a multivariate spatial specification is adopted to capture …


Evaluation Of Left Shoulder As Part-Time Travel Lane Design Alternatives And Transportation Management Center Staff Training Module Development, Zhuohang Deng, Zhiliang Luo, Neil Hockaday, Ahmed Farid, Anurag Pande Jan 2023

Evaluation Of Left Shoulder As Part-Time Travel Lane Design Alternatives And Transportation Management Center Staff Training Module Development, Zhuohang Deng, Zhiliang Luo, Neil Hockaday, Ahmed Farid, Anurag Pande

Mineta Transportation Institute

Permanent capacity expansion, such as adding new lanes, is no longer a viable strategy to address traffic congestion in California; hence, ITS (Intelligent Transportation System) strategies, such as part-time use of the shoulder as a travel lane, need to be explored. The use of the shoulder as a travel lane during peak traffic hours has limited applications in the US, and most use the right shoulder as a part-time travel lane even though either the right or left shoulder (but not both) may be used. Caltrans District 5 is exploring the use of Left Shoulder as a Part-time Travel Lane …