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Articles 1 - 30 of 39
Full-Text Articles in Transportation Engineering
The Effect Of The Socioeconomic Variety In Greater Cairo On Transport Mode Choices, Rafik Yanni
The Effect Of The Socioeconomic Variety In Greater Cairo On Transport Mode Choices, Rafik Yanni
Theses and Dissertations
In the last decade, Egypt has experienced a noticeable upgrade in its infrastructure investment, implementing a lot of transport projects, especially in the Greater Cairo region. In a city with over 20 million residents, variations lie in socioeconomic elements like income, age, gender, and neighborhood, which shape people’s choice of mobility modes based on their culture and lifestyle. The questions then become: whom are these new projects targeting? What are the barriers to using these services? And is there any willingness to change commuting habits if conditions changed? This thesis investigates how the socioeconomic variety in Greater Cairo metropolitan region …
Vibration-Based Algorithm For Diagnostic And Prognostic Condition Monitoring Of Railroad Bearings And Wheels, Jeffery Ray Pams
Vibration-Based Algorithm For Diagnostic And Prognostic Condition Monitoring Of Railroad Bearings And Wheels, Jeffery Ray Pams
Theses and Dissertations
Bearing and wheel failure accounts for the majority of equipment-related train derailments on US railroads. Current wayside monitoring systems have been insufficient in the prevention of catastrophic derailments prompting the rail industry to explore the possible integration of onboard condition monitoring systems into their rail operations. The University Transportation Center for Railway Safety (UTCRS) in partnership with Hum Industrial Technology, Inc., has developed a wireless onboard system intended for the condition monitoring of railroad bearings and wheels. This thesis presents the development, evaluation, and implementation of an algorithm designed to be used in conjunction with these systems to provide railroad …
Hydronic Parking Lots: A Solution For Urban Heat Island Mitigation, Sumeet Jinnappa Paramaj
Hydronic Parking Lots: A Solution For Urban Heat Island Mitigation, Sumeet Jinnappa Paramaj
Theses and Dissertations
The Urban Heat Island (UHI) effect has emerged as a critical challenge in modern cities. It contributes to elevated local temperatures, placing significant stress on urban ecosystems and public health. One of the primary drivers of this phenomenon is the widespread use of impervious surfaces, such as dark-colored parking lots, which absorb heat during the day and gradually release it at night. This ongoing cycle results in persistently warmer urban environments. As cities continue to expand and densify, the need for effective, sustainable strategies to reduce urban heat becomes increasingly urgent.
This project aims to explore innovative interventions, particularly in …
Design Of An Above Pavement Wireless Sensor Node (Apwsn) For Real-Time Roadway Monitoring Using Piezoelectric Energy-Harvesting, Jochy Jonathan Perez
Design Of An Above Pavement Wireless Sensor Node (Apwsn) For Real-Time Roadway Monitoring Using Piezoelectric Energy-Harvesting, Jochy Jonathan Perez
Theses and Dissertations
The evolution of Smart Highway and Internet of Things (IoT) technologies offers new opportunities to improve the safety and efficiency of vehicular traffic on roads. This research effort describes the development of a wireless pavement sensor that provides a novel method to detect key pavement parameters while incorporating low-power energy harvesting that leverages the kinetic energy generated by vehicular traffic. The Above Pavement Wireless Sensor Node (APWSN) is the embodiment of the approach. APWSN can facilitate the strategic deployment of sensors on a wide variety of roads to enable real-time data collection to support decision-making processes for road infrastructure maintenance …
Assessment For Sustainable Transportation Systems In Egypt, Hagar Mohamed Fares
Assessment For Sustainable Transportation Systems In Egypt, Hagar Mohamed Fares
Theses and Dissertations
The assessment of a sustainable transportation system poses a significant challenge for local governments, as it dramatically influences the promotion of environmentally friendly modes of transportation with the objective of safeguarding the public's welfare and health in their daily activities. The integration of such assessment should be implemented from the initial stages of system planning to its operational and maintenance phases, particularly in light of the increasing number of urban development activities nationwide. In order to facilitate decision-making processes, it is imperative to establish an efficient rating system that incorporates cultural and social constraints and comprehensively considers the three dimensions …
A Dedicated Lane Analysis For Supply Chain Resilience In The U.S.-Mexico Border: Cost-Comparison And Simulation Models, Carlo A. Zorola Gonzalez
A Dedicated Lane Analysis For Supply Chain Resilience In The U.S.-Mexico Border: Cost-Comparison And Simulation Models, Carlo A. Zorola Gonzalez
Theses and Dissertations
Supply chains have been actively developing and implementing strategies to enhance resilience in response to various disruptive events like the COVID-19 pandemic, hurricanes, geopolitical tensions, and climate change. These strategies aim to address demand and supply imbalances, logistical challenges, and policy restrictions encountered in transborder commerce. One area significantly impacted by such disruptions is cross-border trade between the US and Mexico. Understanding these strategies is crucial for achieving supply chain resilience, defined as the ability of a supply chain to quickly adapt to sudden disruptions without affecting the flow of goods. In both the US-Mexico and US-Canada borders …
Assessing Military Parking: A Deep Learning Approach To Evaluating Standards And Impacts, Ryan D. Lalonde
Assessing Military Parking: A Deep Learning Approach To Evaluating Standards And Impacts, Ryan D. Lalonde
Theses and Dissertations
Current United States Department of Defense (DoD) standards require a minimum amount of parking for each building. This requirement defines how much off-street parking to construct. However, the impact of these requirements remains unclear. This study builds upon the emerging field of overhead imagery analytics by directly tying it to parking on military installations. Specifically, this study leverages a pretrained deep learning car detection model, Car Detection – USA, developed by Esri for use within ArcGIS, and couples it with open-access temporal imagery sourced from Google Earth Pro to assess selected parking lots across Area B, Wright-Patterson Air Force Base, …
Laboratory Evaluation Of Warm Mix Additives At Lower Than Traditional Compaction Temperatures, Abdelrahman Mahmoud Waheish Ali
Laboratory Evaluation Of Warm Mix Additives At Lower Than Traditional Compaction Temperatures, Abdelrahman Mahmoud Waheish Ali
Theses and Dissertations
The study aims to evaluate the impact of warm mix additives (WMA) on the rheological and performance properties of asphalt binders and mixtures. For this purpose, PG 76-28 and PG 58-28 were obtained with one organic (Sasobit Redux) and three chemical WMA (Rediset, Evotherm, and Zycotherm). All WMA-modified asphalt binders were aged at three different aging levels. Laboratory tests such as performance grade (PG), critical temperature differential (ΔTc), asphalt binder cracking device (ABCD), linear amplitude sweep test (LAS), and Fourier transform infrared spectroscopy (FTIR) were performed. In addition to the binder testing plan, this study also evaluated the impact of …
Vulnerable Road User Safety: Data Collection, Analysis, And Countermeasures, Anahita Kakhani
Vulnerable Road User Safety: Data Collection, Analysis, And Countermeasures, Anahita Kakhani
Theses and Dissertations
The safety of pedestrians and bicyclists (vulnerable road users) has become a paramount global concern, especially with a 53% and 31% surge in related crashes over the past decade in the U.S. Despite transportation agencies implementing various safety measures to address this issue, the number of severe injuries among these road users continues to climb annually. This underscores the urgent need for innovative methodologies and technologies to pinpoint the factors compromising their safety. To do so, this study aimed to introduce and employ techniques and countermeasures to gain deeper insight into risks faced by vulnerable road users. This study includes …
Developing A Smart And Sustainable Public Transportation System: A Case Study In Camden, New Jersey, Zahra Vafakhah
Developing A Smart And Sustainable Public Transportation System: A Case Study In Camden, New Jersey, Zahra Vafakhah
Theses and Dissertations
The transportation sector is a major contributor to air pollution and Greenhouse Gas (GHG) emissions. As a significant source of emissions, public transportation presents an opportunity for mitigation through electrification. However, transitioning to an electric bus fleet necessitates substantial investments in bus procurement and charging infrastructure. To address the associated costs, this study introduces a mixed-integer linear mathematical model developed to optimize the location of on-route fast charging stations within bus networks. The central objective of this optimization formulation is to minimize the overall cost of establishing the charging infrastructure. The study employs a real-world case study focusing on a …
Evaluating The Permeability Of Porous Aggregate Concrete Using Electrical Resistivity-Based Measurements, Ariel Miguel Mendez Aragoncillo
Evaluating The Permeability Of Porous Aggregate Concrete Using Electrical Resistivity-Based Measurements, Ariel Miguel Mendez Aragoncillo
Theses and Dissertations
Recycled concrete aggregates (RCA) and lightweight aggregates (LWA) are popular alternative aggregates for concrete. However, due to their highly porous structure, concrete with RCA and LWA shows a different microstructure and higher permeability than conventional concrete. Thus, the existing relationships used to evaluate the permeability and, consequently, the durability of concrete are not applicable in concretes with RCA and LWA. This research examined the permeation properties of recycled aggregate concrete (RAC) and lightweight aggregate concrete (LWAC). The relationships between electrical resistivity-based measurements in RAC and LWAC and their permeation properties were determined and compared to that of normal weight aggregate …
A Data-Driven Method For Damage Detection In An Open Deck Steel Truss Railroad Bridge Under The Moving Train Load, Mahesh Pokhrel
A Data-Driven Method For Damage Detection In An Open Deck Steel Truss Railroad Bridge Under The Moving Train Load, Mahesh Pokhrel
Theses and Dissertations
Open-Deck (OD) steel truss railroad bridges are one of the most common types of railroad bridges in the United States. They are, however, significantly vulnerable to the dynamic effects of moving train load. In the long run, these dynamic effects cause fatigue damage to the structural members. The damage in most of the railroad bridges are monitored by visual inspections which are sometimes unreliable and inconsistent due to human error. This study explores the identification and classification of damage to an open deck railroad bridge from both time-domain (statistical features) and time-frequency domain features (Hilbert-Huang Transform) extracted through acceleration response …
The Effect Of Four Decades Of Deregulation On Competition And Productivity Of The U.S. Freight Transportation Industry, Seungjae Shin
The Effect Of Four Decades Of Deregulation On Competition And Productivity Of The U.S. Freight Transportation Industry, Seungjae Shin
Theses and Dissertations
This study reviews the competition and productivity of the U.S. freight transportation industry for the past 41 years. This study investigated the trends of HHI market concentration index values and labor productivity values of rail and truck sectors and tried to find any relationships between the two values in the separate periods before and after the abolishment of the ICC. This study also investigated how the existence of a regulatory body impacted productivity of the freight transportation industry by using a Cobb Douglas production function on annual financial statement data in the U.S. stock exchange market. This study found that: …
Piezoresistivity Of Electrically Conductive Asphalt Concrete, Mateo Schmit Mendoza
Piezoresistivity Of Electrically Conductive Asphalt Concrete, Mateo Schmit Mendoza
Theses and Dissertations
Electrically conductive asphalt concrete is considered as a multifunctional construction material due to its structural and non-structural functions. This study aims to investigate piezoresistivity of conductive asphalt concrete. Piezoresistivity is an electrical property of some materials which electrical resistivity changes with induced strain and subsequently, it has the potential for self-sensing smart technology. Graphite Powder F-516 with various contents was added into the asphalt mixtures to impart the electrical conductivity. Electrochemical impedance spectroscopy (EIS) was selected to measure the electrical properties of the specimens in dry and wet conditions, and low and high temperatures. The impedance measurement shows that the …
Wrong-Way Driving: Data Collection, Analysis, And Safety Countermeasures, Parisa Hosseini
Wrong-Way Driving: Data Collection, Analysis, And Safety Countermeasures, Parisa Hosseini
Theses and Dissertations
Wrong-way driving (WWD) crashes have been a long-lasting issue for transportation agencies during the past decades. According to the AAA Foundation's latest statistics, on divided highways, a total of 2,921 WWD fatal crashes were documented from 2010 to 2018, resulting in 3,546 fatalities. In order to analyze WWD events, this study attempts to initially develop a methodology to identify actual WWD crashes from potential WWD crashes in police reports by using text mining and machine learning techniques. Afterward, developing a hazard-based duration model, this study investigates the contributing factors related to the distance traveled by a wrong-way (WW) driver involved …
Inequity Of Access Across America: A Spatial, Temporal, And Modal Disparity Analysis, Sanju Maharjan
Inequity Of Access Across America: A Spatial, Temporal, And Modal Disparity Analysis, Sanju Maharjan
Theses and Dissertations
The overarching goal of this dissertation is to examine the spatial, temporal, and modal disparity of access across America. This is achieved by posing three research objectives. The first objective determines the spatial and temporal disparity of transit and automobile access gap, its impact on transit use, and its socioeconomic and built environment correlates. The second objective examines the spatial and temporal disparity of slightly and extremely risky bike infrastructure and measures the social inequity of access to bike infrastructure. The third objective indicates spatial transit access mismatch between high- and low-wage employment across metropolitans. Three findings are discerned. First, …
Investigating The First/Last Mile Problem In Underserved Communities: A Case Study In Camden City, Nj, Ruqaya Alfaris
Investigating The First/Last Mile Problem In Underserved Communities: A Case Study In Camden City, Nj, Ruqaya Alfaris
Theses and Dissertations
The first/last mile (FLM) is defined as the distance a transiting person should complete before boarding or after alighting at a transit station. The FLM trip is one of the major barriers to access transit, which significantly affects individuals' accessibility to critical services. Specifically, this is prevalent in underserved communities in which public transportation constitutes the major mode of travel. As a case study, the current study discusses the FLM barriers in Camden City, NJ. The study comprehensively reviews the existing literature of the FLM practice to identify the lessons learned from previously conducted plans and programs. To supplement the …
Investigation Of Distracted Driving Events In New Jersey, Ahmed Sajid Hasan
Investigation Of Distracted Driving Events In New Jersey, Ahmed Sajid Hasan
Theses and Dissertations
Every year, thousands of people die in the United States due to crashes involving distracted driving, with this cause contributing to 25% of all fatal traffic crashes in New Jersey in particular. Over the past several years, various techniques (e.g., surveys, crash reports, videos, and simulations) were developed and implemented by the transportation safety community to identify and evaluate distracted driving events. However, these methods collect cross-sectional data on individual subjects and do not provide the actual number of distractions on the road. To fill this gap, this study collected longitudinal data on distracted driving events in the state of …
Assessment Of Key Imperatives For Enhancing Precast Adoptability In Egypt, Mostafa Sameh
Assessment Of Key Imperatives For Enhancing Precast Adoptability In Egypt, Mostafa Sameh
Theses and Dissertations
Precast Concrete’s modular application concept is a major construction method that has been used historically seen in various shapes, forms, and with a wide range of constituents. Examples include Ancient Egypt and China among several impressive structures in old civilizations. The major advantages of precast concrete lie in its adaptability, resilience, and versatility which makes precast concrete one of the most agile building materials. Precast concrete as we know it today has been introduced to our markets over the past several decades. Having similar advantages to that of old precast building methods, the road has been paved for wider use …
Traffic Time Headway Prediction And Analysis: A Deep Learning Approach, Saumik Sakib Bin Masud
Traffic Time Headway Prediction And Analysis: A Deep Learning Approach, Saumik Sakib Bin Masud
Theses and Dissertations
In the modern world of Intelligent Transportation System (ITS), time headway is a key traffic flow parameter affecting ITS operations and planning. Defined as “the time difference between any two successive vehicles when they cross a given point”, time headway is used in various traffic and transportation engineering research domains, such as capacity analysis, safety studies, car-following, and lane-changing behavior modeling, and level of service evaluation describing stochastic features of traffic flow. Advanced travel and headway information can also help road users avoid traffic congestion through dynamic route planning, for instance. Hence, it is crucial to accurately model headway distribution …
Evaluating The Effectiveness Of The Pedestrian Safety Intervention Program: Behavioral And Observational Approach, Deep Patel
Theses and Dissertations
Pedestrians are considered as the most vulnerable road users. On a nationwide scale, according to the National Highway Traffic Safety Administration, there were 6,075 pedestrian fatalities and more than 85,000 pedestrian injuries as a result of traffic crashes in 2017. This study provides national and state pedestrian fatality statistics, a systematic literature review of pedestrian injury severity, observational (video-based) & behavioral (survey-based) evaluation of the Street-Smart NJ pedestrian safety intervention campaign. Street-Smart NJ is a public education, awareness, and behavioral change campaign program that aims to improve pedestrian safety by increasing awareness of pedestrian safety risks and improving compliance with …
Assessment Of Some Of The Common Practices Used In Scheduling Highway Projects, Jennifer Reyes
Assessment Of Some Of The Common Practices Used In Scheduling Highway Projects, Jennifer Reyes
Theses and Dissertations
There are several factors documented in the literature that can affect the accuracy of estimated project durations in highway construction, such as weather, location, and soil conditions. Recently, the Texas Department of Transportation (TxDOT) raised a concern regarding some of the practices used when estimating the contract time for projects. This research presents an assessment of the effect that two practices identified have on the estimated project duration. These two practices include: 1) the estimated lead/lag times in project schedules and 2) scheduling with only critical or controlling activities. The effect of these practices is measured, primarily, by using four …
The Evaluation Of High Molecular Weight Methacrylate As A Treatment Option For Shrinkage Cracks In Airfield Pavement, Austin R. Hayes
The Evaluation Of High Molecular Weight Methacrylate As A Treatment Option For Shrinkage Cracks In Airfield Pavement, Austin R. Hayes
Theses and Dissertations
Air Force policy dictates that only epoxy can be used as a treatment option for shrinkage cracks in concrete airfield pavement. However, since epoxy is not ideal for shrinkage cracks, this research focuses on the evaluation of high molecular weight methacrylate (HMWM) as a treatment option. Laboratory experiments were performed on four sealants to determine whether they could penetrate a crack 24 inches deep, bond to the concrete, and resist water intrusion. Three HMWMs (TK-2415, Kwik Bond KBP 103, and Castek Transpo T-70) and one epoxy (TK-2110) were assessed. The four sealers were applied to 32 concrete specimens with crack …
The Cost Of Jaywalking On Traffic Congestion In An Intersection In Greater Cairo: A Case Study, Hussein Gawdat
The Cost Of Jaywalking On Traffic Congestion In An Intersection In Greater Cairo: A Case Study, Hussein Gawdat
Theses and Dissertations
There have been many studies focusing on different types of traffic delays, pedestrians’ interaction at signalized intersections and economic losses as a result of these delays. However, there is a huge gap in the current literature, regionally and globally, in studying the traffic delays associated with jaywalking. In Egypt, jaywalking is considered a common phenomenon, however, population increased drastically over the past decades in Greater Cairo leading to more congested streets. This research provides a case study that investigates the economic effect of jaywalking on traffic flow in Mashaal, a sample location in Greater Cairo, due to traffic congestion. The …
Risk Analysis Of Autonomous Vehicle And Its Safety Impact On Mixed Traffic Stream, Plaban Das
Risk Analysis Of Autonomous Vehicle And Its Safety Impact On Mixed Traffic Stream, Plaban Das
Theses and Dissertations
In 2016, more than 35,000 people died in traffic crashes, and human error was the reason for 94% of these deaths. Researchers and automobile companies are testing autonomous vehicles in mixed traffic streams to eliminate human error by removing the human driver behind the steering wheel. However, recent autonomous vehicle crashes while testing indicate the necessity for a more thorough risk analysis. The objectives of this study were (1) to perform a risk analysis of autonomous vehicles and (2) to evaluate the safety impact of these vehicles in a mixed traffic stream. The overall research was divided into two phases: …
Evaluating The Impact Of Different Types Of Stabilized Bases On The Overall Performance Of Flexible Pavements, Andrae Anthony Francois
Evaluating The Impact Of Different Types Of Stabilized Bases On The Overall Performance Of Flexible Pavements, Andrae Anthony Francois
Theses and Dissertations
This study was initiated with the aim of evaluating the impact of stabilized and untreated base layers on the performance (i.e., fatigue and rutting) of flexible pavements. Four field sections constructed using stabilized base layers (i.e., bituminous (asphalt emulsion), calcium chloride (CaCl-2), Portland cement, and geogrid stabilized base layers) and a control section constructed using untreated RAP aggregates were analyzed in this study. Falling Weight Deflectometer (FWD) tests were conducted on all the field sections and the collected data was used to backcalculate the elastic moduli for all layers. The influence of the stabilized bases and the untreated RAP base …
Quantifying Transit Access In New York City: Formulating An Accessibility Index For Analyzing Spatial And Social Patterns Of Public Transportation, Maxwell S. Siegel
Quantifying Transit Access In New York City: Formulating An Accessibility Index For Analyzing Spatial And Social Patterns Of Public Transportation, Maxwell S. Siegel
Theses and Dissertations
This paper aims to analyze accessibility within New York City’s transportation system through creating unique accessibility indices. Indices are detailed and implemented using GIS, analyzing the distribution of transit need and access. Regression analyses are performed highlighting relationships between demographics and accessibility and recommendations for transit expansion are presented.
The Application Of Sensors On Guardrails For The Purpose Of Real Time Impact Detection, Matthew D. Sturtevant
The Application Of Sensors On Guardrails For The Purpose Of Real Time Impact Detection, Matthew D. Sturtevant
Theses and Dissertations
The United States roadway system has deteriorated over time due to its age, increasing delays in completing preventative maintenance, and the lack of timely repairs following damage to the infrastructure. Proper asset management drives the need for generalized methods to integrate new sensing capabilities into existing Intelligent Transportation Systems in a time efficient and cost effective manner. In this thesis, we present a methodology for the deployment of new sensors into an existing ITS system. The proposed methodology employs a three phase approach that incorporates data modeling, spatial analysis in Geographic Information Systems, and cost optimization to provide enhanced decision …
Impact Of Snow Removal Operations On Thermoplastic Pavement Markings, Monica L. Monfette
Impact Of Snow Removal Operations On Thermoplastic Pavement Markings, Monica L. Monfette
Theses and Dissertations
This pilot study explored the effect snow removal operations have on thermoplastic pavement markings. Including snow removal as a separate independent variable is unique because much of the previous research performed on pavement marking degradation mentioned snow removal as a direct cause in a marking degrading more rapidly; however, it is mentioned as an afterthought and a suggestion to be considered in future research. This pilot study looked at 10 thermoplastic markings and all marking data were collected in the field, using a hand-held retroreflectometer. Data collected began 60 days after initial marking application and ended 12 months after initial …
Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham
Degradation Modeling Of Polyurea Pavement Markings, Jonathan D. Needham
Theses and Dissertations
Polyurea is a long life pavement marking material used for assets requiring long periods of uninterrupted accessibility. Knowing the performance characteristics of such markings is critical to asset management planning focused on maximizing marking material life-cycles. This paper presents the performance characteristics of polyurea pavement markings in North Carolina using linear regression models. The models generated by this research provide pavement marking managers with tools to better allocate limited manpower and resources in order to optimize budgets while meeting newly proposed pavement marking retroreflectivity levels of service as proposed by the Federal Highway Administration. This research constructed performance models for …