Civil and Environmental Engineering Commons^™

Sizing A New Bike Sharing System For The University Of Nevada, Las Vegas, Nesley Orochena

UNLV Theses, Dissertations, Professional Papers, and Capstones

The strategic planning objectives for a novel Bike Sharing Systems (BSS) are to locate the BSS stations, size the stations, and determine the bicycle fleet size, among others. Current guidelines to design BSS programs are tailored to city centers with large coverage areas and high bicycle to population ratios, and thus not directly transferable to a university setting. An ordered probit model was created using data from a university online stated preference survey to determine the key factors that affect the uptake rates for the UNLV BSS program and to estimate the potential demand. The demand analysis was incorporated into …

Strategic Implications For The United States Of The Belt And Road Initiative In Africa, Alec Monnie

Independent Study Project (ISP) Collection

The belt and road initiative is one of the most significant developments of the twenty-first century, which the United States will need to learn to adapt to. Much of the academic literature regarding the belt and road initiative mentions that Africa is a significant participant in this policy development, but fail to elaborate as to why that is, or what the implications for this are for the United States. This article expands upon the strategic significance of the African continent, and explains the implications thereof for the United States and China. This article argues that the belt and road initiative …

Research On Optimization Of The Ship Routeing System In Qiongzhou Strait, Qifu Wang

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

Toward Car Free Key West, Mary Bishop

Journal of Transportation Demand Management Research

This paper explores the transportation problems created by the large volume of tourist arrivals to the island of Key West, Florida. A survey of visitors to the island was conducted to uncover their perspectives related to the barriers and benefits of various transportation modes in hopes to inform City staff on the development of transportation options that will meet the needs and desires of tourists. The results from 398 respondents revealed a variety of trends, including varying travel choices depending on the number of visits, where visitors were from, and arrival types. From these trends, priority groups for behavior change …

Minimodal: Dimensional Domain Of Miniature Shipping Containers For Intermodal Freight Transportation, Lee Stapley

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

This study explores the feasibility of miniature shipping container usage within existing intermodal transportation (IT) supply chains. Smaller intermodal container shipments may help realign freight shipments with the most efficient transportation mode, rail. These containers embolden the dimensional domain (DD) of shipping. The shipping container dimensional domain (container size variation and modal fluidity) is widespread and results in shipments that are often larger or more infrequent than needed. The DD impacts transport mode, shipping frequency, shipment velocity, intermodal supply chain accessibility, and regional shipping networks. This study suggests that container size impacts the DD and, therefore, mode choice. As miniature …

Developing Algorithms To Detect Incidents On Freeways From Loop Detector And Vehicle Re-Identification Data, Biraj Adhikari

Civil & Environmental Engineering Theses & Dissertations

A new approach for testing incident detection algorithms has been developed and is presented in this thesis. Two new algorithms were developed and tested taking California #7, which is the most widely used algorithm to date, and SVM (Support Vector Machine), which is considered one of the best performing classifiers, as the baseline for comparisons. Algorithm #B in this study uses data from Vehicle Re-Identification whereas the other three algorithms (California #7, SVM and Algorithm #A) use data from a double loop detector for detection of an incident. A microscopic traffic simulator is used for modeling three types of incident …

Deep Reinforcement Learning Approach For Lagrangian Control: Improving Freeway Bottleneck Throughput Via Variable Speed Limit, Reza Vatani Nezafat

Civil & Environmental Engineering Theses & Dissertations

Connected vehicles (CVs) will enable new applications to improve traffic flow. The focus of this dissertation is to investigate how reinforcement learning (RL) control for the variable speed limit (VSL) through CVs can be generalized to improve traffic flow at different freeway bottlenecks. Three different bottlenecks are investigated: A sag curve, where the gradient changes from negative to positive values causes a reduction in the roadway capacity and congestion; a lane reduction, where three lanes merge to two lanes and cause congestion, and finally, an on-ramp, where increase in demand on a multilane freeway causes capacity drop. An RL algorithm …

Wrack Lines Volume 19, Number 1, Spring/Summer 2019, Nancy Balcom, Syma Ebbin, David Gregorio, Richard Telford, Judy Benson

Wrack Lines

Issue theme is: "Making Connections: As the Climate Changes, People and Nature Intertwine in New Ways." Articles include: "As More Roads Become Rivers, Communities Search for Solutions;" "Solving an Engineering Conundrum: As Coastal Homes Get Elevated, New Research Looks at Whether Vulnerability to Wind Damage Is Increasing;" "Along the Coast, Residents Consider How to Heed Sandy's Warning of What's to Come;" "All Rivers, All Lives Run to the Sea," about the intersection of waterways and the world of nature writer Edwin Way Teale; and "Crosscurrents: Connecticut Sea Grant's Retrospective Exhibition Makes Waves," about reaching new audiences and building bridges with …

Analysis Of Disengagements In Semi-Autonomous Vehicles: Drivers’ Takeover Performance And Operational Implications, Francesca M. Favaro, Sky Eurich, Syeda Rizvi, Shivangi Agarwal, Sumaid Mahmood, Nazanin Nader

Mineta Transportation Institute

This report analyzes the reactions of human drivers placed in simulated Autonomous Technology disengagement scenarios. The study was executed in a human-in-the-loop setting, within a high-fidelity integrated car simulator capable of handling both manual and autonomous driving. A population of 40 individuals was tested, with metrics for control takeover quantification given by: i) response times (considering inputs of steering, throttle, and braking); ii) vehicle drift from the lane centerline after takeover as well as overall (integral) drift over an S-turn curve compared to a baseline obtained in manual driving; and iii) accuracy metrics to quantify human factors associated with the …

Do Transportation Network Companies Decrease Or Increase Congestion?, Gregory D. Erhardt, Sneha Roy, Drew Cooper, Bhargava Sana, Mei Chen, Joe Castiglione

Civil Engineering Faculty Publications

This research examines whether transportation network companies (TNCs), such as Uber and Lyft, live up to their stated vision of reducing congestion in major cities. Existing research has produced conflicting results and has been hampered by a lack of data. Using data scraped from the application programming interfaces of two TNCs, combined with observed travel time data, we find that contrary to their vision, TNCs are the biggest contributor to growing traffic congestion in San Francisco. Between 2010 and 2016, weekday vehicle hours of delay increased by 62% compared to 22% in a counterfactual 2016 scenario without TNCs. The findings …

That Bike Is Too Heavy: Merging Bicycling Physics, Human Physiology And Travel Behavior, Alexander Y. Bigazzi

PSU Transportation Seminars

Are the Biketown bikes too heavy? Does better gear motivate people to cycle more? How much faster will someone go on an e-bike?

Although urban cycling is widely known as physically active transportation, the actual physics of cycling have been given little attention in transportation engineering and planning. In contrast, the field of sports science has developed detailed data and models of road bicycle performance, but only for sport and racing cyclists.

What can we learn about utilitarian cycling by integrating knowledge of the physical attributes of bicycles and cyclists?

This seminar examines the ways in which bicycle physics, and …

Auto-Calibration Of Wim Using Traffic Stream Characteristics, Johnson Baker

Graduate Theses and Dissertations

This project evaluates the performance of Weigh-in-Motion (WIM) auto-calibration methods used by the Arkansas Department of Transportation (ARDOT). Typical auto-calibration algorithms compare the WIM measured weights of vehicles from the traffic stream to reference values, using five-axle tractor-trailer configured trucks for comparisons, e.g. Federal Highway Administration (FHWA) Class 9. Parameters of the existing algorithms including the Front Axle Weight (FAW) reference value, the sampling frequency required to update the calibration factor, and thresholds for Gross Vehicle Weight (GVW) bins were evaluated. The primary metric used to estimate algorithm performance was Mean Absolute Percent Error (MAPE) between the WIM and static …

Identifying And Incorporating Driver Behavior Variables Into Crash Prediction Models, Mohammad Razaur Rahman Shaon

Theses and Dissertations

All travelers are exposed to the risk for crashes on the road, as none of the roadways are entirely safe. Under Vision Zero, improving traffic safety on our nation’s highways is and will continue to be one of the most pivotal tasks on the national transportation agenda. For decades, researchers and transportation professionals have strived to identify causal relationships between crash occurrence and roadway geometry, and traffic-related variables on the mission of creating a safe environment for the traveling public. Although great achievements have been witnessed such as the publication of the Highway Safety Manual (HSM), research is rather limited …

Modeling Driver-Pedestrian-Infrastructure Interactions At Signalized Midblock Crosswalks, Boniphace Kutela

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cities and metropolitan areas are increasingly facilitating pedestrians’ movement by the provision of pedestrian walking facilities. As pedestrian traffic increases, the risk of crash involvement increases, especially at midblock locations, where pedestrians are exposed to unsafe interactions with vehicular traffic. To improve pedestrians’ safety at midblock locations, various countermeasures are provided, which include signalized crosswalks. Several studies have analyzed driver-pedestrian interactions, as well as pedestrian-infrastructure interactions at signalized midblock crosswalks. However, more in-depth studies are necessary, due to shortfalls of study assumptions, which have led to the application of improper statistical models, as seen in the literature. Improved models are …

Empleo Regional Y Transporte Público: Un Estudio De Caso Comparado De Accesibilidad Al Transporte De Parques Industriales En El Gran Buenos Aires Basado En La Medida De Sistema De Información Geográfica, Clara Wang

Independent Study Project (ISP) Collection

La accesibilidad al transporte es considerada como un elemento crítico del desarrollo urbano y además la clave del empleo. Este informe intenta analizar el problema de la baja tasa del empleo local enfrente de Malvinas Argentinas (MA)en relación con el bajo nivel de conectividad entre la zona industrial y residencial del municipio. Para contextualizar el problema de este desequilibrio en la región metropolitana de Buenos Aires, La Matanza (LM) será el caso de estudio por tratarse de un municipio similar en localización y estructura industrial. El Sistema de Información Geográfica (SIG) se utiliza para análisis de espacio y visualización de …

Latent Choice Models To Account For Misclassification Errors In Discrete Transportation Data, Lacramioara Elena Balan

Civil & Environmental Engineering Theses & Dissertations

One of the most fundamental tasks when it comes to analyzing data using statistical methods is to understand the relationship between the explanatory variables and the outcome. Misclassification of explanatory variables is a common risk when using statistical modeling techniques. In this dissertation, we define ‘misclassification,’ as a response that is reported or recorded in the wrong category; for example, a variable is registered as a one when it should have the value zero. Misclassification can easily happen in any data; for example, in an interview setting where the respondent misunderstands the question or the interviewer checks the wrong box. …

Webinar: Rethinking Streets For Bikes: An Evidence Based Guide Of Bike-Friendly Street Retrofits, Marc Schlossberg, Roger Lindgren

TREC Webinar Series

There is a growing demand for better infrastructure and fewer barriers to biking and other forms of space-efficient micromobility. Tackling daily trips by bike is easier on the environment, healthier for users and non-users alike, uses precious urbanized public and private land more efficiently, costs taxpayers less to build and maintain infrastructure, and when routes are safe and comfortable, moving by bike is also fun! Complete Streets policies are being adopted across the country, and there is an active conversation around the safety imperative of a Complete Streets approach. Yet, local officials often need both design guidance and the …

Webinar: Modeling Freeway Traffic In A Mixed Environment: Connected And Human-Driven Vehicles, Xianfeng Terry Yang

TREC Webinar Series

Although connected vehicles (CVs) will soon go beyond testbeds, CVs and human-driven vehicles (HVs) will co-exist over a long period. Hence, it is critical to consider the interactions between these two types of vehicles in traffic flow modeling. In this study, we aim to develop a macroscopic model to understand how CVs would impact HVs in the traffic stream. Grounded on the second-order traffic flow model, we study the relationships among flow, density, and speed by two sets of formulations for the groups of CVs and HVs, respectively. A set of friction factors, which indicate CVs' impact to HVs, are …

The Resilient City: A Platform For Informed Decision-Making Process, Paul Niculescu-Mizil Gheorghe, Jarutpong Vasuthanasub, Adrian Gheorghe

Engineering Management & Systems Engineering Faculty Publications

As over half of the world’s inhabitants lives in metropolises, the rapid growth in urbanization has made cities becoming more and more exposed and vulnerable to a broad spectrum of threats and hazards. In order to respond to such difficulties, a concept of resilience is considered a significant component for the long-term planning and sustainable development of the cities. “Resilient City” is a new paradigm that challenges the idealistic principle of stability and resistance to change implicitly in sustainable development and success. However, building a resilient city requires a holistic approach, as well as the appropriate adoption of knowledge and …

An Initial Exploration Of The 2005 Iowa Rural Interstate Speed Limit Increase Using Linear Regression, Thomas Ryan Cook

Electronic Theses and Dissertations

Speed limit increases, particularly on interstates have been studied and researched many times over the course of the last 50 years in the United States. These research efforts began after the implementation of the National Maximum Speed Law (NMSL), which reduced all speed limits to a maximum of 55-mph. In the years that followed, this restriction was relaxed to 65-mph with the Surface Transportation and Uniform Relocation Assistance Act (STURAA) and ultimately repealed later by the National Highway System Designation Act (NHSDA). Since the repeal, states reacted in myriad of ways and many studies documented the changes of those reactions. …