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Full-Text Articles in Transportation

The Legacy Of Car-Share And Light-Rail Transit For Mobility And Accessibility Improvements In Economically Marginalized Neighborhoods In The New York Metro Area, Kyeongsu Kim Feb 2021

The Legacy Of Car-Share And Light-Rail Transit For Mobility And Accessibility Improvements In Economically Marginalized Neighborhoods In The New York Metro Area, Kyeongsu Kim

Dissertations, Theses, and Capstone Projects

This dissertation explores the value of the car-share program and a new light rail system with respect to their impact on mobility and accessibility improvements in economically and transportation access-wise marginalized neighborhoods in NYC and its adjacent communities. It consists of three main essays that took deep dives into how each new service or system altered mobility or accessibility for those in need. The first essay (Chapter 2) investigates car-share vehicle utilization rates of the Zipcar across NYC. It assesses the utilization rates by vehicle type, service location, time period, and weekday usage compared to weekend activity. With a multivariate …


The Use Of Dynamic Message Signs (Dmss) On The Freeways: An Empirical Analysis Of Dmss Logs And Survey Data, Boniphace Kutela, Hualiang Teng Jan 2021

The Use Of Dynamic Message Signs (Dmss) On The Freeways: An Empirical Analysis Of Dmss Logs And Survey Data, Boniphace Kutela, Hualiang Teng

Civil and Environmental Engineering and Construction Faculty Research

This study evaluates the Dynamic Message Signs (DMSs) use to dissipate incident information on the freeways in Las Vegas, Nevada. It focuses on the DMSs message timing, extent, and content, from the operators’ and drivers’ perspectives, considering the variability in drivers’ freeway experience. Two-week incidents data with fifty-nine incidents, DMS log data, and responses from a survey questionnaire were used. The descriptive analysis of the incidents revealed that about 54% of the incidents had their information posted on the DMSs; however, information of only 18.6% of the incidents was posted on time. The posted information covered the incident type (54.2%), …


Zone Path Construction (Zac) Based Approaches For Effective Real-Time Ridesharing, Meghna Lowalekar, Pradeep Varakantham, Patrick Jaillet Jan 2021

Zone Path Construction (Zac) Based Approaches For Effective Real-Time Ridesharing, Meghna Lowalekar, Pradeep Varakantham, Patrick Jaillet

Research Collection School Of Computing and Information Systems

Real-time ridesharing systems such as UberPool, Lyft Line and GrabShare have become hugely popular as they reduce the costs for customers, improve per trip revenue for drivers and reduce traffic on the roads by grouping customers with similar itineraries. The key challenge in these systems is to group the “right” requests to travel together in the “right” available vehicles in real-time, so that the objective (e.g., requests served, revenue or delay) is optimized. This challenge has been addressed in existing work by: (i) generating as many relevant feasible combinations of requests (with respect to the available delay for customers) as …


Workshop Outcomes Report: 1st International Workshop On Seismic Resilience Of Arctic Infrastructure And Social Systems, Majid Ghayoomi, Katharine Duderstadt, Alexander Kholodov, Alexander Shiklomanov, Matthew Turner, Elham Ajorlou Jan 2021

Workshop Outcomes Report: 1st International Workshop On Seismic Resilience Of Arctic Infrastructure And Social Systems, Majid Ghayoomi, Katharine Duderstadt, Alexander Kholodov, Alexander Shiklomanov, Matthew Turner, Elham Ajorlou

Faculty Publications

No abstract provided.


Exploring And Visualizing Spatial Effects And Patterns In Ride-Sourcing Trip Demand And Characteristics, Bishoy Kelleny, Sherif Ishak Jan 2021

Exploring And Visualizing Spatial Effects And Patterns In Ride-Sourcing Trip Demand And Characteristics, Bishoy Kelleny, Sherif Ishak

Civil & Environmental Engineering Faculty Publications

The complex demand pattern of ride-sourcing remains to be a challenge to transportation modeling practitioners due to the infancy and the inherently dynamic nature of the ride-sourcing system. Spatial effects exploration and analysis protocols can provide informative insights on the underlying structure of demand and trip characteristics. Those protocols can be thought of as an opportunistic strategy to alleviate the complexity and help specifying the appropriate econometric models for the system. Spatial effects exploration is comparable to point pattern analysis, in which, signals from spatial entities, like census tracts, can be analyzed statistically to reveal whether a specific phenomenon respective …


Online Bus Speed Prediction With Spatiotemporal Interaction: A Laplace Approximation-Based Bayesian Approach, Haipeng Cui, Kun Xie, Bin Hu, Hangfei Lin Jan 2021

Online Bus Speed Prediction With Spatiotemporal Interaction: A Laplace Approximation-Based Bayesian Approach, Haipeng Cui, Kun Xie, Bin Hu, Hangfei Lin

Civil & Environmental Engineering Faculty Publications

This study proposes a novel Bayesian hierarchical approach for online bus speed prediction by explicitly accounting for the spatiotemporal interaction (STI) of speed observations. The use of Laplace approximation can expedite the estimation of Bayesian models and enable the implementation of online prediction. Large numbers of trials are carried out to identify significant predictors and the optimal length of the look-back time window to achieve the highest prediction accuracy. The spatiotemporal interacting patterns are also explored, and results show that the Type IV model assuming the structured spatial effect interacts with the structured temporal effect can best accommodate the bus …


Modeling And Simulation Of Cascading Failures In Transportation Systems During Hurricane Evacuations, Yuan Zhu, Kaan Ozbay, Hong Yang, Fan Zuo, Di Sha Jan 2021

Modeling And Simulation Of Cascading Failures In Transportation Systems During Hurricane Evacuations, Yuan Zhu, Kaan Ozbay, Hong Yang, Fan Zuo, Di Sha

Computational Modeling & Simulation Engineering Faculty Publications

Effective and timely evacuation is critical in alleviating the impact of hurricanes. As such, evacuation models are often sought to support the preparedness of evacuations. One important task in the modeling process is to evaluate exogenous factors that cause transportation system capacity loss during evacuation. Typical factors include direct damage to the roadway network due to storm surge and cascading impacts because of other facilities failures. For example, power outage can lead to signal failure and subway suspension. This paper aims to develop a macroscopic simulation-based approach to study the capacity loss of the roadway network in evacuation due to …


Time Domain Boundary Element Method Prediction Of Noise Shielding By A Naca 0012 Airfoil, Douglas M. Nark, Fang Q. Hu Jan 2021

Time Domain Boundary Element Method Prediction Of Noise Shielding By A Naca 0012 Airfoil, Douglas M. Nark, Fang Q. Hu

Mathematics & Statistics Faculty Publications

As aircraft noise constraints become more stringent and the number/mixture of aircraft configurations grows, it becomes more important to understand the interaction of individual aircraft noise sources with nearby aircraft structures. Understanding these interactions and exploring possible approaches to mitigate or exploit their acoustic impact is essential for overcoming key noise barriers. This paper describes the further validation of a time domain boundary element approach for the prediction of the interactions between incident noise sources and nearby aircraft structures. Predictions were completed for multiple source locations and comparisons of these results with measured data are presented. Overall, very good agreement …


Conceptual Development Of A Probabilistic Graphical Framework For Assessing Port Resilience, Katherine Smith, Rafael Diaz, Yuzhong Shen, Francesco Longo Jan 2021

Conceptual Development Of A Probabilistic Graphical Framework For Assessing Port Resilience, Katherine Smith, Rafael Diaz, Yuzhong Shen, Francesco Longo

VMASC Publications

Technological advances such as cyber physical systems and autonomous vehicles combined with increased disruptions including the Covid-19 pandemic and coastal natural disasters have heightened the importance of port risk analysis methodologies and frameworks that can accurately quantify and optimize resilience. This work presents the conceptual development of a novel combination of analysis methodologies linking a probabilistic graphic approach on a network of risk events with a functional dependency approach on a system network. Key advantages of these two methodologies are the ability to model and learn causal interactions rather than simply correlations and a high level of computational efficiency. This …


Numerical Investigations Of Transient Wind Shear From Passing Vehicles Near A Road Structure (Part I: Unsteady Reynolds-Averaged Navier-Stokes Simulations), Hamid Rahai, Assma Begum Jan 2021

Numerical Investigations Of Transient Wind Shear From Passing Vehicles Near A Road Structure (Part I: Unsteady Reynolds-Averaged Navier-Stokes Simulations), Hamid Rahai, Assma Begum

Mineta Transportation Institute

In this research, the authors performed unsteady numerical simulations of a moving Ahmed body under a freeway overpass at different distances from the bridge columns in order to evaluate transient wind shear and the wind load on these columns. Results have shown that when the vehicle is at 0.75W distance from the bridge columns, an unsteady wind speed of up to 24 m/s is observed at the columns with a pressure coefficient difference of 0.9. Here W is the width of the vehicle. These results indicate with an appropriate system for harnessing these wind energy potentials, significant renewable electric power …


Developing Guidelines For Assessing The Effectiveness Of Intelligent Compaction Technology, Mehran Mazari, Siavash F. Aval, Siddharth M. Satani, David Corona, Joshua Garrido Jan 2021

Developing Guidelines For Assessing The Effectiveness Of Intelligent Compaction Technology, Mehran Mazari, Siavash F. Aval, Siddharth M. Satani, David Corona, Joshua Garrido

Mineta Transportation Institute

Many factors affect pavement compaction quality, which can vary. Such variability may result in an additional number of passes required, extended working hours, higher energy consumption, and negative environmental impacts. The use of Intelligent Compaction (IC) technology during construction can improve the quality and longevity of pavement structures while reducing risk for contractors and project owners alike. This study develops guidelines for the implementation of IC in the compaction of pavement layers as well as performing a preliminary life-cycle cost analysis (LCCA) of IC technology compared to the conventional compaction approach. The environmental impacts of the improved construction process were …


Maritime Robotics And Autonomous Systems Operations : Exploring Pathways For Overcoming International Techno-Regulatory Data Barriers, Tafsir Martin Johansson, Dimitrios Dalaklis, Aspasia Pastra Jan 2021

Maritime Robotics And Autonomous Systems Operations : Exploring Pathways For Overcoming International Techno-Regulatory Data Barriers, Tafsir Martin Johansson, Dimitrios Dalaklis, Aspasia Pastra

Articles

The current regulatory landscape that applies to maritime service robotics, aptly termed as robotics and autonomous systems (RAS), is quite complex. When it comes to patents, there are multifarious considerations in relation to vessel survey, inspection, and maintenance processes under national and international law. Adherence is challenging, given that the traditional delivery methods are viewed as unsafe, strenuous, and laborious. Service robotics, namely micro aerial vehicles (MAVs) or drones, magnetic-wheeled crawlers (crawlers), and remotely operated vehicles (ROVs), function by relying on the architecture of the Internet of Robotic Things. The aforementioned are being introduced as time-saving apparatuses, accompanied by the …


Smart Parking Systems: Reviewing The Literature, Architecture And Ways Forward, Can Biyik, Zaheer Allam, Gabriele Pieri, Davide Moroni, Muftah O' Fraifer, Eoin O' Connell, Stephan Olariu, Muhammad Khalid Jan 2021

Smart Parking Systems: Reviewing The Literature, Architecture And Ways Forward, Can Biyik, Zaheer Allam, Gabriele Pieri, Davide Moroni, Muftah O' Fraifer, Eoin O' Connell, Stephan Olariu, Muhammad Khalid

Computer Science Faculty Publications

The Internet of Things (IoT) has come of age, and complex solutions can now be implemented seamlessly within urban governance and management frameworks and processes. For cities, growing rates of car ownership are rendering parking availability a challenge and lowering the quality of life through increased carbon emissions. The development of smart parking solutions is thus necessary to reduce the time spent looking for parking and to reduce greenhouse gas emissions. The principal role of this research paper is to analyze smart parking solutions from a technical perspective, underlining the systems and sensors that are available, as documented in the …


Local Climate Action Planning As A Tool To Harness The Greenhouse Gas Emissions Mitigation And Equity Potential Of Autonomous Vehicles And On-Demand Mobility, Serena Alexander, Asha Weinstein Agrawal, Benjamin Y. Clark Jan 2021

Local Climate Action Planning As A Tool To Harness The Greenhouse Gas Emissions Mitigation And Equity Potential Of Autonomous Vehicles And On-Demand Mobility, Serena Alexander, Asha Weinstein Agrawal, Benjamin Y. Clark

Mineta Transportation Institute

This report focuses on how cities can use climate action plans (CAPs) to ensure that on-demand mobility and autonomous vehicles (AVs) help reduce, rather than increase, green-house gas (GHG) emissions and inequitable impacts from the transportation system. We employed a three-pronged research strategy involving: (1) an analysis of the current literature on on-demand mobility and AVs; (2) a systematic content analysis of 23 CAPs and general plans developed by municipalities in California; and (3) a comparison of findings from the literature and content analysis of plans to identify opportunities for GHG emissions reduction and mobility equity.

Findings indicate that maximizing …


Examining Bicycle And Motorized Vehicle Speeds And Their Relationships In The Context Of Urban Roadways, Jaclyn Sue Schaefer Dec 2020

Examining Bicycle And Motorized Vehicle Speeds And Their Relationships In The Context Of Urban Roadways, Jaclyn Sue Schaefer

Dissertations and Theses

This thesis presents a compilation of papers exploring passenger car and bicycle speeds through their interactions with each other and with urban roadway factors.

First, following a concern raised in part of the traffic literature that a large mode shift toward bicycling may cause travel time delays and potentially exacerbate congestion instead of alleviate it unless bicycle lanes are installed, an empirical study detailing how the presence of bicycles on urban roads without bicycle lanes may affect passenger car speeds is presented. Pneumatic tube data from six predominantly low speed, low volume roads in Portland, Oregon were utilized to identify …


Enhanced Traffic Incident Analysis With Advanced Machine Learning Algorithms, Zhenyu Wang Dec 2020

Enhanced Traffic Incident Analysis With Advanced Machine Learning Algorithms, Zhenyu Wang

Computational Modeling & Simulation Engineering Theses & Dissertations

Traffic incident analysis is a crucial task in traffic management centers (TMCs) that typically manage many highways with limited staff and resources. An effective automatic incident analysis approach that can report abnormal events timely and accurately will benefit TMCs in optimizing the use of limited incident response and management resources. During the past decades, significant efforts have been made by researchers towards the development of data-driven approaches for incident analysis. Nevertheless, many developed approaches have shown limited success in the field. This is largely attributed to the long detection time (i.e., waiting for overwhelmed upstream detection stations; meanwhile, downstream stations …


A Parametric Analysis Of A Turbofan Engine With An Auxiliary Bypass Combustion Chamber – The Turboaux Engine, Kaleab Fetahi Dec 2020

A Parametric Analysis Of A Turbofan Engine With An Auxiliary Bypass Combustion Chamber – The Turboaux Engine, Kaleab Fetahi

Mechanical & Aerospace Engineering Theses & Dissertations

A parametric study of a novel turbofan engine with an auxiliary combustion chamber, nicknamed the TurboAux engine is presented. The TurboAux engine is conceived as an extension of a low-bypass turbofan engine with an auxiliary bypass annular combustion chamber around the core stream. The study presented in this thesis is motivated by the need to facilitate clean secondary burning of fuel at temperatures higher than conventionally realized, from air exiting the low-pressure compressor. The parametric study starts by analyzing the turbojet engine and its performance with and without an afterburner segment attached. Following that, the conventional turbofan and its mixing …


Methodologies To Quantify Transit Performance Metrics At The System-Level Using High-Resolution Gps, Stop-Level, And Gtfs Archived Transit Data, Travis Bradley Glick Nov 2020

Methodologies To Quantify Transit Performance Metrics At The System-Level Using High-Resolution Gps, Stop-Level, And Gtfs Archived Transit Data, Travis Bradley Glick

Dissertations and Theses

Performance metrics have typically focused at two main scales: a microscopic scale that focuses on specific locations, time-periods, and trips; and, a macroscopic scale that averages metrics over longer times, entire routes, and networks. When applied to entire transit systems, microscopic methodologies often have computational limitations while macroscopic methodologies ascribe artificial uniformity to non-uniform analysis areas. These limitations highlight the need for a middle approach.

This dissertation presents a mesoscopic analysis based around timepoint-segments, which are a novel application of an existing system for many transit agencies. For this research, routes are divided into a consecutive group of bus stops …


Feasibility Study Of The Implementation Of An Effective And Eco-Friendly Energy Management System : Case Study Of Palermo's Fincantieri Shipyard, Bryan Singer Asturias Nov 2020

Feasibility Study Of The Implementation Of An Effective And Eco-Friendly Energy Management System : Case Study Of Palermo's Fincantieri Shipyard, Bryan Singer Asturias

World Maritime University Dissertations

No abstract provided.


The Development Of An Operational Kpi For Energy Efficiency Ship Operation, Danuja Wijayanto Nov 2020

The Development Of An Operational Kpi For Energy Efficiency Ship Operation, Danuja Wijayanto

World Maritime University Dissertations

No abstract provided.


The Energy Efficiency Of Maritime Autonomous Surface Ship (Mass), Dang Cuong Nguyen Nov 2020

The Energy Efficiency Of Maritime Autonomous Surface Ship (Mass), Dang Cuong Nguyen

World Maritime University Dissertations

No abstract provided.


Accident Analysis And Prevention : Application Of Hfacs In Maritime Casualty Investigation Reports Of Ecuador, David Guevara Haro Nov 2020

Accident Analysis And Prevention : Application Of Hfacs In Maritime Casualty Investigation Reports Of Ecuador, David Guevara Haro

World Maritime University Dissertations

No abstract provided.


Promoting Maritime Safety Through ‘Findings’ Of Accident Investigations, Surveys And Audits In The Pacific : The Case Of Papua New Guinea, Conny Ralph Hauseng Nov 2020

Promoting Maritime Safety Through ‘Findings’ Of Accident Investigations, Surveys And Audits In The Pacific : The Case Of Papua New Guinea, Conny Ralph Hauseng

World Maritime University Dissertations

No abstract provided.


The Application Of Renewable Energy Supply In A Port Container Terminal : Bandar Abbas Port Container Terminal Case Study, Zhila Gordani Nov 2020

The Application Of Renewable Energy Supply In A Port Container Terminal : Bandar Abbas Port Container Terminal Case Study, Zhila Gordani

World Maritime University Dissertations

No abstract provided.


An Equity Focused Study On The Trip Temporal Distributions Of Vulnerable Road Users, Santiago Espinosa Wild Oct 2020

An Equity Focused Study On The Trip Temporal Distributions Of Vulnerable Road Users, Santiago Espinosa Wild

Civil and Environmental Engineering Master's Project Reports

The United States is a megadiverse nation with a transportation system that, for decades, was designed to serve primarily able-bodied, white, male motorists. This legacy creates a situation in which varying socio-demographic groups experience the transportation system differently with contrasting safety, accessibility, and convenience outcomes. This project introduces descriptive statistics and binary logistic models that provide transportation professionals and policy makers with a quantitative understanding on how, why, and when certain socio-demographic groups are more likely to engage in a trip. This project provides tools to measure and understand the equity implications of a wide array of transportation policy decisions. …


Online Traffic Signal Control Through Sample-Based Constrained Optimization, Srishti Dhamija, Alolika Gon, Pradeep Varakantham, William Yeoh Oct 2020

Online Traffic Signal Control Through Sample-Based Constrained Optimization, Srishti Dhamija, Alolika Gon, Pradeep Varakantham, William Yeoh

Research Collection School Of Computing and Information Systems

Traffic congestion reduces productivity of individuals by increasing time spent in traffic and also increases pollution. To reduce traffic congestion by better handling dynamic traffic patterns, recent work has focused on online traffic signal control. Typically, the objective in traffic signal control is to minimize expected delay over all vehicles given the uncertainty associated with the vehicle turn movements at intersections. In order to ensure responsiveness in decision making, a typical approach is to compute a schedule that minimizes the delay for the expected scenario of vehicle movements instead of minimizing expected delay over the feasible vehicle movement scenarios. Such …


Deep Reinforcement Learning Approach To Solve Dynamic Vehicle Routing Problem With Stochastic Customers, Waldy Joe, Hoong Chuin Lau Oct 2020

Deep Reinforcement Learning Approach To Solve Dynamic Vehicle Routing Problem With Stochastic Customers, Waldy Joe, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In real-world urban logistics operations, changes to the routes and tasks occur in response to dynamic events. To ensure customers’ demands are met, planners need to make these changes quickly (sometimes instantaneously). This paper proposes the formulation of a dynamic vehicle routing problem with time windows and both known and stochastic customers as a route-based Markov Decision Process. We propose a solution approach that combines Deep Reinforcement Learning (specifically neural networks-based TemporalDifference learning with experience replay) to approximate the value function and a routing heuristic based on Simulated Annealing, called DRLSA. Our approach enables optimized re-routing decision to be generated …


Non-Conventional Vehicles As A Way Towards Carbon Neutrality In Iceland, Julia Sokolowska Oct 2020

Non-Conventional Vehicles As A Way Towards Carbon Neutrality In Iceland, Julia Sokolowska

Independent Study Project (ISP) Collection

Paris Agreement’s chief objective is to protect the Earth and its inhabitants from a point of no return, when the effects of climate change will be so intense that they will shift the equilibrium of ecosystems. The distinctiveness of this international environmental treaty is that it does not impose climate change mitigation measures, but rather allows nation states to create their own set of measures, the NDCs, to reach the global warming of ‘well below 2oC’ by the end of the century. Thus, Iceland has submitted its own NDC, the Climate Action Plan 2018-2030, which has an ambitious goal of …


Zone Path Construction (Zac) Based Approaches For Effective Real-Time Ridesharing, Meghna Lowalekar, Pradeep Varakantham, Patrick Jaillet Sep 2020

Zone Path Construction (Zac) Based Approaches For Effective Real-Time Ridesharing, Meghna Lowalekar, Pradeep Varakantham, Patrick Jaillet

Research Collection School Of Computing and Information Systems

Real-time ridesharing systems such as UberPool, Lyft Line, GrabShare have become hugely popular as they reduce the costs for customers, improve per trip revenue for drivers and reduce traffic on the roads by grouping customers with similar itineraries. The key challenge in these systems is to group the "right" requests to travel together in the "right" available vehicles in real-time, so that the objective (e.g., requests served, revenue or delay) is optimized. This challenge has been addressed in existing work by: (i) generating as many relevant feasible (with respect to the available delay for customers) combinations of requests as possible …


Bus Frequency Optimization: When Waiting Time Matters In User Satisfaction, Songsong Mo, Zhifeng Bao, Baihua Zheng, Zhiyong Peng Sep 2020

Bus Frequency Optimization: When Waiting Time Matters In User Satisfaction, Songsong Mo, Zhifeng Bao, Baihua Zheng, Zhiyong Peng

Research Collection School Of Computing and Information Systems

Reorganizing bus frequency to cater for the actual travel demand can save the cost of the public transport system significantly. Many, if not all, existing studies formulate this as a bus frequency optimization problem which tries to minimize passengers’ average waiting time. However, many investigations have confirmed that the user satisfaction drops faster as the waiting time increases. Consequently, this paper studies the bus frequency optimization problem considering the user satisfaction. Specifically, for the first time to our best knowledge, we study how to schedule the buses such that the total number of passengers who could receive their bus services …