Engineering Commons^™

Investigating Changes In Trends Of Traffic Crashes Due To Covid-19 Pandemic In Florida’S Freeways, Ntagwanko Kisabanzira

UNF Graduate Theses and Dissertations

The COVID-19 pandemic outbreak caused a shift in traffic patterns that have in turn influenced a change in traffic accident trends. Due to stay-at-home orders that were issued across the United States, transportation agencies reported low traffic demands on highways after the pandemic outbreak. Low traffic volumes are associated with relatively higher speeds that are linked to increased severity of crashes. Several states reported an increase in fatal crashes after the outbreak of the COVID-19 pandemic. This paper evaluates the traffic crash trends on three interstates in Florida (I-10, I-75, and I-95) and sheds light on what happened before, during, …

Crystalline Analysis Of Geomicrobially-Induced Calcium Carbonate Precipitation In Sands Using A Surface Percolation Treatment Technique, Justin Edward Mulloney

UNF Graduate Theses and Dissertations

Ottawa 50/70 sand specimens and natural beach sand samples were treated using bio-augmented geomicrobies via a surface percolation technique. Testing was conducted on these specimens to determine how resultant calcium carbonate precipitation changed as a function of temperature, depth from the surface, and in the presence of magnesium. Specifically, x-ray Diffraction (XRD), a Scanning Electron Microscope (SEM), and Energy Dispersive X-ray Spectroscopy (EDS) were used to determine and quantify the presence of calcium carbonate and its associated phase. Results showed a direct relationship between temperature and precipitated calcium carbonate. In addition, as an unintended consequence associated with the treatment, ammonium …

Analyzing Benefits Of Connected Vehicle Technologies During Incidents On Freeways And Diversion Strategies Implementation: A Microsimulation-Based Case Study Of Florida's Turnpike, Francisca P. Kasubi

UNF Graduate Theses and Dissertations

The full utilization of connected vehicles (CVs) is highly anticipated to become a reality soon. As CVs become increasingly prevalent in our roadway network, connected technologies have enormous potential to improve safety. This study conducted a microscopic simulation to quantify the benefits of CVs in improving freeway safety along a 7.8-mile section on Florida’s Turnpike (SR-91) system. The simulation incorporated driver compliance behavior in a CV environment. The simulation was implemented via an existing VISSIM network model partially developed by the Florida Department of Transportation (FDOT). In addition, the study analyzed how CVs would assist in detour operations as a …

Linear Generators In Wave Energy Conversion: Performance, Feasibility, And Location Study, Luis Fernandez De Valderrama

UNF Graduate Theses and Dissertations

As the energy demand increases and climate change becomes a major problem, the solution to decrease greenhouse gas emissions and mitigate the effects of climate change involves increasing the use of sustainable and renewable sources to generate electricity. However, developed renewable sources have inconveniences that make them incapable of generating the totality of the electricity that a country demands. Wave energy is an alternative renewable energy source that can help mitigate the inconveniences of other renewable sources and decrease the emission of greenhouse gases.

This study aims to find the potential of linear generators in wave energy by analyzing the …

Exploring The Use Of Drones For Conducting Traffic Mobility And Safety Studies, Abdallah N. Kinero

UNF Graduate Theses and Dissertations

ABSTRACT

Advanced traffic data collection methods, including the application of aerial sensors (drones) as traffic data collectors, can provide real-time traffic information more efficiently, effectively, and safely than traditional methods. Traffic trajectory data like vehicles’ coordinates and point timestamps are challenging to obtain at intersections using traditional field survey methods. The coordinates and timestamps crucial in calculating trajectories can be obtained using drones and their particular integrated software. Thus, this study explores the use of unmanned aerial systems (UAS), particularly tethered drones, to obtain traffic parameters for traffic mobility and safety studies at an unsignalized intersection in Tallahassee, Florida. Tethered …

Modeling Coastal Vulnerability Of The St. Johns River And Northeastern Florida Shorelines, Madison E. Heppe

UNF Graduate Theses and Dissertations

Coastal and riverine communities, with anthropogenic congestion and natural and economic resources, are vulnerable to climate change impacts including rising sea levels and increasing severity and frequency of storms. Coastal habitats are being increasingly recognized as natural infrastructure that provides resiliency against these stressors. However, few studies have analyzed coastal vulnerability at landscape scale with finely resolved spatial data that account for habitats and demographics. The purpose of this study is to map the coastal vulnerability of the St. Johns River and adjacent Northeastern Florida Atlantic shoreline within the St. Johns River Water Management District. Unique to this study is …

A Microscopic Simulation Approach For Developing Ramp Metering Activation Guidelines For Weekends, Sarah T. Kasomi

UNF Graduate Theses and Dissertations

Traffic congestion is one of the major concerns in urban motorways. Agencies are implementing various Transportation Systems Management and Operations (TSM&O) strategies to reduce traffic congestion on roadway networks. Ramp metering is a TSM&O strategy that utilizes signals installed at freeways’ on-ramps to dynamically manage traffic entering the freeway. RMSs have been effective at alleviating recurring congestion. Recurring congestion, however, constitutes less than half of all congestion. More than half of all congestion is due to non-recurring events such as incidents, work zones, adverse weather conditions, special events, etc., that adversely affect the performance of a highway. Non-recurring congestion on …

Analysis Of Shallow Water Underwater Noise From Marine Pile Driving Using Computational Fluid Dynamics And Empirical Data Fitting, Moses Bosco

UNF Graduate Theses and Dissertations

There has been a growing concern in recent years about the effects of anthropogenic noise due to pile driving on underwater wildlife. Current guidelines for mitigating hydroacoustic effects associated with these geotechnical events are based upon a relatively simple transmission loss formulation known as the Practical Spreading Loss Model (PSLM). This model is easy to implement, but it may produce overly conservative results. Sound data during pile drives from several sites in Florida showed much higher sound attenuation than predicted by the PSLM. The first part of this study focused on explaining this discrepancy using computational fluid dynamics. Specifically, synthetic …

Determination Of Extreme Flood Events In The Black Creek, Julington Creek, Dubin Creek, Big Davis Creek, Ortega River, And Pablo Creek Sub-Basins Of The Lower St. Johns River Basin, Florida, Usa, Samantha Kovalenko

UNF Graduate Theses and Dissertations

Extreme flood estimation is a continuously developing field of research. Economic and community well-being are dependent on flood risk preventative planning, which can only be successfully implemented through sound flood estimating methods. Without the execution of proper flood prevention measures, many communities remain at risk. In addition to a new extreme flood estimation methodology, this research presents a new approach to establish flood estimates. Traditionally, more than one flood estimate per return frequency storm does not exist. This research produced a set of 10-, 25-, 50-, and 100-year flood estimates for the Black Creek, Julington Creek, Durbin Creek, Big Davis …

Estimating A Range Of Flow Rates Resulting From Extreme Storm Events Within The Wekiva River Watershed Through Statistical Testing And Modeling, Wesley K. Koning

UNF Graduate Theses and Dissertations

The middle portion of the St. Johns River is located in East-Central Florida, USA. This region of the St. Johns River is increasingly subject to urbanization and conversion of forest areas to agricultural land. Overall, these changes mean that future flood events in the area could adversely impact local citizens. Therefore, the examination of extreme flood events and resiliency to such events is critical. The purpose of this preliminary study is to explore a range of practical applications to estimate extreme flood flows at watercourses within the Middle St. Johns River Basin, focusing specifically upon the Wekiva River sub-basin. The …

Preliminary Design And Analysis Of A Wave Energy Converter With Electromagnetic Induction, Laura Fernandez De Valderrama

UNF Graduate Theses and Dissertations

As the energy demand increases with the constantly increasing population, as well as the effort to replace conventional fossil fuels with cleaner sources of energy, ocean energy has emerged as a potential global resource. The ocean contains an enormous amount of energy that has not been exploited yet, although efforts have augmented during the past decades.

The overall purpose of this research is to design, model, and analyze, a wave energy converter (WEC) prototype to contribute to the current research in this field. This particular work represents the first stage of the research process in which the ultimate goal is …

Synthesis And Characterization Of Carbon Sequestering Calcium Carbonate Cement, Mohammad Jobaer Uddin

UNF Graduate Theses and Dissertations

The cement industry is the second-largest manufacturing emitter of CO₂, and the manufacture and placement of concrete accounts for 7-8% of anthropogenic CO2 emissions. There is increasing pressure on the cement industry to develop a sustainable cement to support rapid global urban development without the associated emissions of cement production. The calcination reaction required to manufacture Portland cement is the prime source of emissions, so eliminating the release of CO₂ liberated during calcination of limestone provides an excellent opportunity to produce a more sustainable cement. Calcium carbonate (CaCO₃) cement is a novel alternative, which can …

Developing And Simulating A Communication Plan For Mitigation Of Secondary Crashes: Leveraging Connected Vehicle Technologies, Denis Elia Monyo

UNF Graduate Theses and Dissertations

The Federal Highway Administration (FHWA) has identified secondary crashes (SCs) on United States (US) highways as one of the core transportation issues that needs to be addressed. These crashes contribute to increased property damage, injuries, and fatalities and a decline in traffic flow conditions on freeways and adjacent arterials. The purpose of this study was to 1) propose a communication plan that leverages connected vehicle (CV) technologies to increase awareness to road users to target the mitigation of SCs, and 2) to evaluate the potential benefits of the proposed communication plan with CV technologies in alleviating SCs.

This study used …

Investigating The Leading Causes Of Fatalities Of Aging Pedestrians Using Bayesian Network Model, Luciano Lalika

UNF Graduate Theses and Dissertations

Identifying factors associated with older pedestrian fatalities is key to implementing strategies aimed at improving pedestrian safety. This study focused on investigating the leading risk factors for older pedestrian fatalities at Florida roadway intersections. Analyses consisted of a Bayesian logistic regression (BLR) model to identify significant factors influencing pedestrian fatality, followed by a Bayesian Network (BN) model to identify the leading cause of pedestrian fatality among the statistically significant risk factors. Furthermore, the probabilistic inference of the leading causes of older pedestrian fatalities obtained from the BN was conducted through individual evidence predictive inference, diagnostic inference, and combined evidence predictive …

A Computational Analysis Of Marine Fenders Under Heavy Weather Mooring Conditions, Zachary Eskew

UNF Graduate Theses and Dissertations

Dynamic loading of marine fenders is a situation that is unique to the United States Navy (USN), due to the use of Heavy Weather Mooring (HWM) for naval vessels during extreme weather events, such as hurricanes. Traditional analysis has not been concerned with the fender reaction on vessel hulls. However, newer classes of Naval ships, such as the Littoral Combat Ships (LCS), have designs that emphasize speed and agility, resulting in them having thinner hulls more susceptible to damage from fenders. In traditional analysis, fenders are modeled as idealized springs, with static- load derived spring constants from manufacturer charts. This …

Investigation Of Expedient, Cost Effective And Sustainable Soil Stabilization For Tactical Vehicles Using Surfactant-Induced Soil Stabilization (Siss), Joshua Sasser

UNF Graduate Theses and Dissertations

Surfactant-induced soil stabilization (SISS) is a new method for soil stabilization whereby anionic surfactants and alkaline earth metals are introduced to a soil matrix. This research served as a preliminary study into SISS’ suitability as a temporary soil stabilization method that could be used to improve wheeled vehicle traction during amphibious type naval operations conducted on a beach head.

Beach sand specimens were treated with sodium dodecyl sulfate (SDS; aka sodium lauryl sulfate) and calcium chloride using two methods: hand mixing in testing cylinders and surface percolation in bench scale sandboxes. Treated cylinders were tested for unconfined compressive strength (UCS) …

Evaluating Mobility And Safety Benefits Of Freeway Service Patrols: A Case Study Of Florida's Road Rangers, Jimoku H. Salum

UNF Graduate Theses and Dissertations

The Florida’s Road Rangers monitor the freeways for incidents to minimize their adverse impacts on traffic. The objectives of this study were to evaluate the extent to which Road Rangers reduce incident clearance duration (ICD), incident-induced traffic delays (IITDs) and secondary crashes (SCs).

Since ICD distributions are often right-skewed, the study applied quantile regression to relate ICD to influencing factors. Data skewed to the right is usually a result of lower bounds in a data set being extremely low relative to the rest of the data. Data from 28,000 incidents that occurred on freeways in Jacksonville, Florida were analyzed. Of …

Evaluating The Mobility And Safety Benefits Of Adaptive Signal Control Technology (Asct), John Herman Kodi

UNF Graduate Theses and Dissertations

The Adaptive Signal Control Technology (ASCT) is a traffic management strategy that optimizes signal timing based on real-time traffic demand. This thesis proposes a comprehensive methodology of quantifying the mobility and safety benefits of the ASCT deployed in the state of Florida. A Bayesian switch-point regression model was proposed to evaluate the mobility benefits of ASCT. The analysis was based on a 3.3-mile corridor along Mayport Road from Atlantic Boulevard to Wonderwood Drive in Jacksonville, Florida. The proposed analysis was used to estimate the possible dates that separate the two operating characteristics, i.e., with and without ASCT. Also, the posterior …

Testing Coulwave For Use In Modeling Cross-Shore Sand Transport And Beach Profile Evolution, Patrick Michael Cooper

UNF Graduate Theses and Dissertations

Realistic, reliable, and effective modeling of cross-shore sediment transport is not present in the current literature. Building that model requires the accurate recreation of breaking wave processes in the nearshore. To develop that first step for an as-yet-to-be-designed model, multiple phase-resolving wave transformation algorithms are reviewed for in-depth investigation. The COULWAVE model is selected for robust testing. Testing of the COULWAVE model shows that, although capable of recreating realistic results, it does not adequately describe major wave characteristics in the surf zone, across a wide range of conditions, to warrant use in a future cross-shore sediment transport model.

Simulation Exploration Of The Potential Of Connected Vehicles In Mitigating Secondary Crashes, Mike Alvin Soloka

UNF Graduate Theses and Dissertations

Secondary crashes (SCs) on freeways are a major concern for traffic incident management systems. Studies have shown that their occurrence is significant and can lead to deterioration of traffic flow conditions on freeways in addition to injury and fatalities, albeit their magnitudes are relatively low when compared to primary crashes. Due to the limited nature of crash data in analyzing freeway SCs, surrogate measures provide an alternative for safety analysis for freeway analysis using conflict analysis. Connected Vehicles (CVs) have seen compelling technological advancements since the concept was introduced in the 1990s. In recent years, CVs have emerged as a …

Development, Validation, And Utilization, Of A Long-Term Nearshore Synthetic Wave Record, Sergio A. Pena

UNF Graduate Theses and Dissertations

The need for a consistent and accurate production of long-term nearshore wave record is discussed. With multiple decades of offshore hindcasts and long, continuous data sets available, it is possible to create a nearshore synthetic wave record. The Brevard County coastline offers an area with a high quality 62-year long offshore hindcast, as well as an 11-year long and nearly continuous high-resolution nearshore wave record to compare with model performance. This thesis presents the steps in the development and performance of the synthetic nearshore wave record produced. A novel approach was used to compare, validate and calibrate this type of …

Operational Effectiveness Of Connected Vehicle Smartphone Technology On A Signalized Corridor, Festo Mjogolo

UNF Graduate Theses and Dissertations

Over the last decade, extensive research efforts have been placed on performance evaluation and the benefits of innovative CV applications. Findings indicate that CV technology can effectively mitigate the safety, mobility, and environmental challenges experienced on transportation networks. Most of research evaluated CV technology through simulation studies. However, a field study provides a more ideal method of assessing CV technology effectiveness. Therefore, a field study to obtain the actual effectiveness of CV technology was warranted, to validate previous findings, and to add to the body of knowledge surrounding this topic. This thesis presents both a field study and simulation evaluation …

The Operational And Safety Effects Of Heavy Duty Vehicles Platooning, Ahmed Alzahrani

UNF Graduate Theses and Dissertations

Abstract

Although researchers have studied the effects of platooning, most of the work done so far has focused on fuel consumption. There are a few studies that have targeted the impact of platooning on the highway operations and safety. This thesis focuses on the impact of heavy-duty vehicles (HDVs) platooning on highway characteristics. Specifically, this study aims at evaluating the effects of platooning of HDVs on capacity, safety, and CO₂ emissions.

This study is based on a hypothetical model that was created using the VISSIM software. VISSIM is a powerful simulation software designed to mimic the field traffic flow …

Investigating The Effects Of Rainfall On Traffic Operations On Florida Freeways, Lucia Andrew

UNF Graduate Theses and Dissertations

Rainfall affects the performance of traffic operations and endangers safety. A common and conventional method (rain gauges) for rainfall measurements mostly provide precipitation records in hourly and 15-minute intervals. However, reliability, continuity, and wide area coverage pose challenges with this data collection method. There is also a greater likelihood for data misrepresentation in areas where short duration rainfall is predominant, i.e., reported values may not reflect the actual equivalent rainfall intensity during subintervals over the entire reporting period. With recent weather and climate patterns increasing in severity, there is a need for a more effective and reliable way of measuring …

A Study On Erosion Resistance For Microbially Induced Calcite Treated Beach Sand, Abigail Chek

UNF Graduate Theses and Dissertations

Microbial induced calcite precipitation (MICP) was used to treat several sandboxes filled with naturally occurring beach sand collected from Atlantic Beach, FL. Unlike most previous MICP studies, a surface-spray technique was used to treat these sandboxes where relatively high-concentration bacteria solution and high concentration calcium chloride/urea solutions were applied directly to the boxes’ surfaces. Several different treatment combinations were tested whereby bacterial optical density, bacteria/urea/calcium chloride volume relative to void space, and bacteria/urea/calcium chloride ratio were manipulated. Treated sandboxes were tested for erodibility using a pocket erodometer and for calcification using a wash method. In addition, sandboxes were dissected after …

Evaluating The Performance Of Cooperative Merging Assistance System For Aging Drivers, Flavius Matata

UNF Graduate Theses and Dissertations

Freeway merging maneuvers demand considerable attention by drivers and are among the more complex operations drivers must perform on freeways. Aging drivers, a growing population in the United States, face added challenges when merging. This study utilized Vissim models created in a previous study that modeled the behavior of aging drivers during freeway merging. An algorithm for Cooperative Merging Assistance System (CMAS) that utilizes Connected Vehicle (CV) technology was developed in this study. The Vissim models were created for two interchanges on I-75 in Fort Myers, Florida, each with different geometric characteristics. Acceleration lane lengths of 1000ft and 1500ft were …

An Analysis Of Hydroacoustic Transmission Loss Associated With Marine Pile Driving, Jonathan Paul Berube

UNF Graduate Theses and Dissertations

There has been a growing concern in recent years about the effects of anthropogenic noise due to marine pile driving on underwater wildlife. Current guidelines for mitigating hydroacoustic effects associated with these events are based upon relatively simple transmission loss formulations. The advantage to these guidelines is that computing transmission loss using their prescribed methods is not labor intensive, but their disadvantage is that they may not take all variables into account. Because of this, it may be possible to improve transmission loss computations. To better-characterize marine pile driving sound transmission loss, a unique in-water instrumentation system was developed. This …

The Use Of Real-Time Connected Vehicles And Here Data In Developing An Automated Freeway Incident Detection Algorithm, Hendry Nyanza Imani

UNF Graduate Theses and Dissertations

Traffic incidents cause severe problems on roadways. About 6.3 million highway crashes are reported annually only in the United States, among which more than 32,000 are fatal crashes. Reducing the risk of traffic incidents is key to effective traffic incident management (TIM). Quick detection of unexpected traffic incidents on roadways contribute to quick clearance and hence improve safety. Existing techniques for the detection of freeway incidents are not reliable.

This study focuses on exploring the potential of emerging connected vehicles (CV) technology in automated freeway incident detection in the mixed traffic environment. The study aims at developing an automated freeway …

Effect Of Vessel-Generated Waves In Near Low Tide Conditions On Shorelines In The Intracoastal Waterways, Mackenzie Lee Sanchez

UNF Graduate Theses and Dissertations

Erosion is caused when there is a net loss of sediment in a coastal system, i.e. when the amount of sediment leaving a system is more than the amount of sediment entering that same system. This investigation will focus on vessel-generated waves and their effect on the shorelines of the Jacksonville, Florida Intracoastal Waterways near low tide conditions. The investigation conducted herein examines variations in turbidity and pressure measurements in response to passing vessels at a single site location previously selected in 2016. The primary water/shoreline interaction recorded during this investigation is located below the visible scarp (near low tide …

Development Of Forward And Inversion Schemes For Cross-Borehole Ground Penetrating Radar, Donald Jones

UNF Graduate Theses and Dissertations

Tomography is an imaging technique to develop a representation of the internal features of material using a penetrating wave, such as an electromagnetic wave. The calculation method used is an example of an inverse problem, which is a system where the input and the output are known but the internal parameters are not. These parameters can be estimated by understanding the responses of a penetrating wave as it passes through the unknown media. A forward problem is just the opposite; the internal structure and input penetrating wave is known and the output is determined. For both forward and inverse problems, …