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Comparison Of A Modified And Traditional Rapid Infiltration Basin For Treatment And Control Of Nutrients In Wastewater Effluent, Jessica Cormier
Comparison Of A Modified And Traditional Rapid Infiltration Basin For Treatment And Control Of Nutrients In Wastewater Effluent, Jessica Cormier
Electronic Theses and Dissertations
Rapid infiltration basins (RIB) have been historically used in Florida for groundwater recharge, effluent disposal, or a combination of both. However, this technique has proven ineffective in providing nitrogen control unless the RIB is modified in some manner. In this study, a traditional RIB was compared to a modified RIB constructed with manufactured biosorption activated media (BAM) to evaluate nitrate removal from reclaimed water. The RIBs are used for reclaimed and excess storm water disposal. Few, if any, studies have been published where BAM-modified RIBs have been used for this purpose. In this work, a mixture of clay, tire crumb, …
Electrochemical Microsensors For In Situ Monitoring Of Chemical Compounds In Engineered And Natural Aquatic Systems, Jared Church
Electrochemical Microsensors For In Situ Monitoring Of Chemical Compounds In Engineered And Natural Aquatic Systems, Jared Church
Electronic Theses and Dissertations
The adaption of needle-type electrochemical microsensor (or microelectrode) techniques to environmental science and engineering systems has transformed how we understand mass transport in biotic and abiotic processes. Their small tip diameter (5-20μm) makes them a unique experimental tool for direct measurements of analytes with high spatial and temporal resolutions, providing a quantitative analysis of flux, diffusion, and reaction rate at a microscale that cannot be obtained using conventional analytical tools. However, their applications have been primarily limited to understanding mass transport dynamics and kinetics in biofilms. With the advancement of sensor fabrication and utilization techniques, their potential applications can surpass …
Nanofiltration Of Perfluorinated Compounds As A Function Of Water Matrix Properties, Hadi Toure
Nanofiltration Of Perfluorinated Compounds As A Function Of Water Matrix Properties, Hadi Toure
Electronic Theses and Dissertations
Perfluorinated compounds (PFCs) have been manufactured and used in various industries including food packaging, paintings, and coating industries. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are the most commonly investigated PFCs that have bioaccumulative properties and a strong persistence in environment. Despite the growing interest in using membrane technology to remove PFOA and PFOS from water, little information is available on the impact of natural water matrices on the removal of PFOA and PFOS when using nanofiltration (NF). The presence of natural organic matter (NOM) and cations (Ca2+ and Mg2+) in water matrices and their interactions with the PFCs …
A Framework For Assessing Sustainability Impacts Of Truck Routing Strategies, Haluk Laman
A Framework For Assessing Sustainability Impacts Of Truck Routing Strategies, Haluk Laman
Electronic Theses and Dissertations
The impact of freight on our transportation system is further accentuated by the fact that trucks consume greater roadway capacity and therefore cause more significant problems including traffic congestion, delay, crashes, air pollution, fuel consumption, and pavement damage. Assessing the actual effects of truck traffic is a growing need to support the ability to safely and efficiently move goods and people in areas where roadway expansion is not the best option. On one hand, trucks need to efficiently serve commerce and industry, while at the same time their activities need not contribute to a decline in the quality or public …
Fusing Freight Analysis Framework And Transearch Data: An Econometric Data Fusion Approach, Salah Uddin Momtaz
Fusing Freight Analysis Framework And Transearch Data: An Econometric Data Fusion Approach, Salah Uddin Momtaz
Electronic Theses and Dissertations
A major hurdle in freight demand modeling has always been the lack of adequate data on freight movements for different industry sectors for planning applications. Freight Analysis Framework (FAF), and Transearch (TS) databases contain annualized commodity flow data. The primary motivation for our study is the development of a fused database from FAF and TS to realize transportation network flows at a fine spatial resolution (county-level) while accommodating for production and consumption behavioral trends (provided by TS). Towards this end, we formulate and estimate a joint econometric model framework grounded in maximum likelihood approach to estimate county-level commodity flows. The …
Econometric Modeling Analysis Of Public Transit Ridership: Application For Orlando Region, Moshiur Rahman
Econometric Modeling Analysis Of Public Transit Ridership: Application For Orlando Region, Moshiur Rahman
Electronic Theses and Dissertations
Policy makers are considering several alternatives to counter the negative externalities of personal vehicle dependence. Towards this end, public transit investments are critical in growing urban regions such as Orlando, Florida. Transit system managers and planners mostly rely on statistical models to identify the factors that affect ridership as well as quantifying the magnitude of the impact on the society. These models provide vital feedback to agencies on the benefits of public transit investments which in turn act as lessons to improve the investment process. We contribute to public transit literature by addressing several methodological challenges for transit ridership modeling. …
Understanding How, Where And How Much Freight Flows Using 2012 Commodity Flow Survey Data, Nowreen Keya
Understanding How, Where And How Much Freight Flows Using 2012 Commodity Flow Survey Data, Nowreen Keya
Electronic Theses and Dissertations
In recent years, with increased economic globalization, growing e-commerce and internet based shopping, freight movement patterns are undergoing a transformative change. The shipment size distribution is moving towards a higher share of smaller size shipments affecting transportation mode and vehicle type requirements. In addition, freight transportation mode is closely affected by the destination location (and its attributes). In our dissertation, we contribute to freight research by developing a comprehensive framework to examine the how, where and how much freight flows in US. Specifically, we study the following dimensions of freight flow: (1) transportation mode, (2) mode and shipment weight choice …
Cost And Environmental Impacts Of Leachate Nitrogen/Phosphorus Management Approaches, Alaa Alanezi
Cost And Environmental Impacts Of Leachate Nitrogen/Phosphorus Management Approaches, Alaa Alanezi
Electronic Theses and Dissertations
Landfill leachate is a challenging wastewater to discharge into municipal wastewater treatment plants (WWTPs), the most common approach for leachate management, due to the presence of contaminants that may affect the performance of the treatment plant. Treatment, disposal, and transportation of leachate are expensive and therefore a concern. Currently, sidestream treatment is becoming increasingly common in WWTPs prior to returning the liquid to the plant influent. For this research, a new treatment scheme is introduced combining centrate and leachate to reduce contaminants, recover phosphorous and nitrogen through struvite precipitation, and reduce energy requirements through anaerobic ammonium oxidation (Anammox). By combining …
Safety Investigation Of Traffic Crashes Incorporating Spatial Correlation Effects, Khalid Alkahtani
Safety Investigation Of Traffic Crashes Incorporating Spatial Correlation Effects, Khalid Alkahtani
Electronic Theses and Dissertations
One main interest in crash frequency modeling is to predict crash counts over a spatial domain of interest (e.g., traffic analysis zones (TAZs)). The macro-level crash prediction models can assist transportation planners with a comprehensive perspective to consider safety in the long-range transportation planning process. Most of the previous studies that have examined traffic crashes at the macro-level are related to high-income countries, whereas there is a lack of similar studies among lower- and middle-income countries where most road traffic deaths (90%) occur. This includes Middle Eastern countries, necessitating a thorough investigation and diagnosis of the issues and factors instigating …
Evaluation And Augmentation Of Traffic Data From Private Sector And Bluetooth Detection System On Arterials, Yaobang Gong
Evaluation And Augmentation Of Traffic Data From Private Sector And Bluetooth Detection System On Arterials, Yaobang Gong
Electronic Theses and Dissertations
Traffic data are essential for public agencies to monitor the traffic condition of the roadway network in real-time. Recently, public agencies have implemented Bluetooth Detection Systems (BDS) on arterials to collect traffic data and purchased data directly from private sector vendors. However, the quality and reliability of the aforementioned two data sources are subject to rigorous evaluation. The thesis presents a study utilizing high-resolution GPS trajectories to evaluate data from HERE, one of the private sector data vendors, and BDS of arterial corridors in Orlando, Florida. The results showed that the accuracy and reliability of BDS data are better than …
Evaluating The Integration Of Chlorine Dioxide Into A Coagulation, Sedimentation, And Filtration Process Treating Surface Water, Martin Coleman
Evaluating The Integration Of Chlorine Dioxide Into A Coagulation, Sedimentation, And Filtration Process Treating Surface Water, Martin Coleman
Electronic Theses and Dissertations
Methods of optimizing the coagulation, flocculation, sedimentation, and filtration (CSF) process at a conventional surface water treatment plant (WTP) were conducted to investigate opportunities for the reduction of disinfection by-product (DBP) precursor material. The research had two primary components: (1) optimize coagulant dosage and associated operating pH and (2) investigate pretreatment oxidation with chlorine dioxide (ClO2) and potassium permanganate (KMnO4). To accomplish the first component, jar tests were conducted at various pH and aluminum sulfate (alum) dosages to model current and potential treatment conditions during the CSF process at a WTP. Isopleths were developed to examine the removal efficiencies of …
Accommodating Exogenous Variable And Decision Rule Heterogeneity In Discrete Choice Models: Application To Bicyclist Route Choice, Bibhas Dey
Electronic Theses and Dissertations
The thesis contributes to our understanding of incorporating heterogeneity in discrete choice models with respect to exogenous variables and decision rules. Specifically, we evaluate latent segmentation based mixed models that allow for segmenting population based on decision rules while also incorporating unobserved heterogeneity within the segment level decision rule models. In our analysis, we choose to consider the random utility framework along with random regret minimization approach. Further, instead of assuming the number of segments (as 2), we conduct an exhaustive exploration with multiple segments across the two decision rules. Within each segment we also allow for unobserved heterogeneity. The …
A Holistic Analysis Of The Long-Term Challenges & Potential Benefits Of The Green Roof, Solar Pv Roofing, And Gripv Roofing Markets In Orlando, Florida, Carolina Kelly
Electronic Theses and Dissertations
Green roofs and roof-mounted solar PV arrays have a wide range of environmental and economic benefits, including significantly longer roof lifetimes, reductions in urban runoff, mitigation of the urban heat island (UHI) effect, reduced electricity demand and energy dependence, and/or reduced emissions of greenhouse gases (GHGs) and other harmful pollutants from the electricity generation sector. Consequently, green roofs and solar panels have both become increasingly popular worldwide, and promising new research has emerged for their potential combination in Green Roof Integrated Photovoltaic (GRIPV) roofing applications. However, due to policy resistance, these alternatives still have marginal market shares in the U.S., …
Seepage And Stability Analysis Of The Earth Dams Under Drawdown Conditions By Using The Finite Element Method, Salama Al-Labban
Seepage And Stability Analysis Of The Earth Dams Under Drawdown Conditions By Using The Finite Element Method, Salama Al-Labban
Electronic Theses and Dissertations
One of the major concerns in the behavior of an earth dam is the change in the exit gradient and the impact on the slope stability under drawdown conditions. Drawdown can cause increased seepage forces on the upstream slope which may result in the movement of soil particles in the flow direction and cause erosion problems. In this research, a numerical approach, based on the finite element method (FEM) is used to analyze the seepage through the dam and its foundation to study exit gradients and slope stability under both steady-state and transient conditions. The results show that a central …
Harmful Algal Bloom Mitigating Using Recycled Concrete Aggregate Coated With Fixed-Quat., Ikenna Ezeodurukwe
Harmful Algal Bloom Mitigating Using Recycled Concrete Aggregate Coated With Fixed-Quat., Ikenna Ezeodurukwe
Electronic Theses and Dissertations
Human activities generate surplus nutrients which may lead to algal bloom events in water resources along with serious ecological problems and thus substantial economic losses. Particularly, harmful algal blooms (HABs) represent toxic cyanobacterial blooms which produce cyanotoxins. The primary concerns of HABs are the exposures to a wide variety of cyanotoxins via ingestion of contaminated drinking water, inhalation during recreational activities, and consumption of contaminated fish and shellfish. However, conventional physical and chemical methods are not always possible to efficiently handle these HABs events. It is urgent to develop viable and rapid solutions to control HABs in field and mitigate …
Dynamic Hotspot Identification For Limited Access Facilities Using Temporal Traffic Data, Samer Al Amili
Dynamic Hotspot Identification For Limited Access Facilities Using Temporal Traffic Data, Samer Al Amili
Electronic Theses and Dissertations
Crash frequency analysis is the most critical tool to investigate traffic safety problems. Therefore, an accurate crash analysis must be conducted. Since traffic continually fluctuates over time and this effects potential of crash occurrence, shorter time periods and less aggregated traffic factors (shorter intervals than AADT) need to be used. In this dissertation, several methodologies have been conducted to elevate the accuracy of crash prediction. The performance of using less aggregated traffic data in modeling crash frequency was explored for weekdays and weekends. Four-time periods for weekdays and two time periods for weekends, with four intervals (5, 15, 30, and …
Investigating And Facilitating The Transferability Of Safety Performance Functions, Ahmed Tarek Ahmed Farid
Investigating And Facilitating The Transferability Of Safety Performance Functions, Ahmed Tarek Ahmed Farid
Electronic Theses and Dissertations
Safety performance functions (SPFs) are essential analytical tools in the road safety field. The SPFs are statistical regression models used to predict crash counts by roadway facility type, crash type and severity. The national Highway Safety Manual (HSM) is a generic guidebook used for road safety evaluation and enhancement. In it, default SPFs, developed using negative binomial (NB) regression, are provided for multiple facility types and crash categories. Roadway agencies, whether public or private, may opt to not invest their resources in data collection and processing to develop own localized SPFs. Instead, the agencies may adopt the HSM's. However, the …
Hierarchical Corridor Safety Analysis Using Multiple Approaches, Saif Alarifi
Hierarchical Corridor Safety Analysis Using Multiple Approaches, Saif Alarifi
Electronic Theses and Dissertations
Traffic crashes are a major cause of concern globally. Extensive efforts from transportation professionals have been made to investigate new methods to identify the contributing factors to crashes at various locations on the road network. Corridors, among other road network's components, play a vital role in moving people and goods between primary zones in different areas, and the safety and operational improvements of them have been the focus of many studies since they carry the most traffic on the road network. Corridors contain mainly intersections and segments, and previous corridor studies have focused on a sole type of road entity. …
A Decision Support Model For Autonomous Trucks Strategies, Ahmad Mohamed
A Decision Support Model For Autonomous Trucks Strategies, Ahmad Mohamed
Electronic Theses and Dissertations
We examined the potential to improve the movement of freight using Truck Platooning Lane strategies on limited access highways in the State of Florida. In the First part of this research, we investigated the potential benefits from dedicating one lane from existing lanes for autonomous trucks only. In this regard, a general framework tool was developed to evaluate and compare different measurements (e.g., travel tim and emissions) to better assist decision makers to determine the most effective freight transportation strategy. Additionally, the travel time, level of service and emissions on Florida Strategic Intermodal System (SIS) were systematically analyzed using a …
Sinkhole Detection And Quantification Using Lidar Data, Amirarsalan Rajabi
Sinkhole Detection And Quantification Using Lidar Data, Amirarsalan Rajabi
Electronic Theses and Dissertations
The state of Florida is highly prone to sinkhole incident and formation, mainly because of the soluble carbonate bedrock which is susceptible to dissolution and groundwater recharge that causes internal soil erosions. Numerous sinkholes, particularly in Central Florida, have occurred. Florida Subsidence Incident Report (FSIR) database contains verified sinkholes with Global Positioning System (GPS) information. In addition to existing detection methods such as subsurface exploration and geophysical methods, a remote sensing method can be an alternative and efficient means to detect and characterize sinkholes with a wide coverage. the first part of this study is aimed at developing a method …
Assessing The Impact Of Radionuclides Released Into The Floridan Aquifer By A Massive Sinkhole On Local Municipal Water Supplies, Maria Arenas Daza
Assessing The Impact Of Radionuclides Released Into The Floridan Aquifer By A Massive Sinkhole On Local Municipal Water Supplies, Maria Arenas Daza
Electronic Theses and Dissertations
In late August 2016, a sinkhole spanning 45 feet (13.7 meters) in diameter opened at a phosphate fertilizer facility (Mosaic Company) near Mulberry, Florida, leaking an estimated 215 million gallons (813,000 cubic meters) of radionuclide-contaminated water 300 feet into the Floridan aquifer. An investigation to determine possible impacts to the environment and local community drinking water supplies was implemented that focused on two 1.5 million gallon per day (MGD) Tampa Bay Water (TBW) production wells and two Polk County Utilities (PCU) water treatment facilities. Water samples collected between June 2017 and January 2018 at the TBW and PCU sites were …
Performance Predication Model For Advance Traffic Control System (Atcs) Using Field Data, Masood Mirza
Performance Predication Model For Advance Traffic Control System (Atcs) Using Field Data, Masood Mirza
Electronic Theses and Dissertations
Reductions in capital expenditure revenues have created greater demands from users for quality service from existing facilities at lower costs forcing agencies to evaluate the performance of projects in more comprehensive and "greener" ways. The use of Adaptive Traffic Controls Systems (ATCS) is a step in the right direction by enabling practitioners and engineers to develop and implement traffic optimization strategies to achieve greater capacity out of the existing systems by optimizing traffic signal based on real time traffic demands and flow pattern. However, the industry is lagging in developing modeling tools for the ATCS which can predict the changes …
Treatment Of Leachate Organic Matter Through Sunlight Driven Processes, Duncan Lozinski
Treatment Of Leachate Organic Matter Through Sunlight Driven Processes, Duncan Lozinski
Electronic Theses and Dissertations
The ability to manage leachate during post-closure care (PCC) of a landfill may be increasingly difficult as leachate organic matter (LOM) becomes recalcitrant when a landfill ages, requiring advanced and costly treatment technologies. This research investigated the ability to treat LOM through sunlight driven processes, with a focus on photolysis, to provide insight to landfill owners and operators on the potential of wetlands treatment as a means for reducing long-term risks and costs associated with leachate treatment during PCC. The study was completed in eight batch tests, where leachate was exposed to natural sunlight in central Florida for a period …
Analyzing Destination Choices Of Tourists And Residents From Location Based Social Media Data, Md Mehedi Hasnat
Analyzing Destination Choices Of Tourists And Residents From Location Based Social Media Data, Md Mehedi Hasnat
Electronic Theses and Dissertations
Ubiquitous uses of social media platforms in smartphones have created an opportunity to gather digital traces of individual activities at a large scale. Traditional travel surveys fall short in collecting longitudinal travel behavior data for a large number of people in a cost effective way, especially for the transient population such as tourists. This study presents an innovating methodological framework, using machine learning and econometric approaches, to gather and analyze location-based social media (LBSM) data to understand individual destination choices. First, using Twitter's search interface, we have collected Twitter posts of nearly 156,000 users for the state of Florida. We …
Explore Contributing Geometric Factors And Built-Environment On Bicycle Activity And Safety At Intersections, Scott Castro
Explore Contributing Geometric Factors And Built-Environment On Bicycle Activity And Safety At Intersections, Scott Castro
Electronic Theses and Dissertations
This study attempts to explore all factors associated with bicycle motor-vehicle crashes at intersections in order to improve bicycle safety and bicycle activity. Factors such as exposure (bicycle and vehicle volumes), existing facilities (bike lanes, sidewalks, shared-use paths), geometric design (# of lanes, speed limit, medians, legs, roadway conditions), and land-use were collected and evaluated using Poisson, Zero-Inflated Poisson, and Negative Binomial models in SAS 9.4 software. Increasing the bicycle travel mode can have positive lasting effects on personal health, the environment, and improve traffic conditions. Deterrents that keep users from riding bicycles more are the lack of facilities and …
Applying Machine Learning Techniques To Analyze The Pedestrian And Bicycle Crashes At The Macroscopic Level, Md Sharikur Rahman
Applying Machine Learning Techniques To Analyze The Pedestrian And Bicycle Crashes At The Macroscopic Level, Md Sharikur Rahman
Electronic Theses and Dissertations
This thesis presents different data mining/machine learning techniques to analyze the vulnerable road users' (i.e., pedestrian and bicycle) crashes by developing crash prediction models at macro-level. In this study, we developed data mining approach (i.e., decision tree regression (DTR) models) for both pedestrian and bicycle crash counts. To author knowledge, this is the first application of DTR models in the growing traffic safety literature at macro-level. The empirical analysis is based on the Statewide Traffic Analysis Zones (STAZ) level crash count data for both pedestrian and bicycle from the state of Florida for the year of 2010 to 2012. The …
Development And Application Of An Optimization Approach For Cost-Effective Deployment Of Advanced Wrong-Way Driving Countermeasures, Adrian Sandt
Electronic Theses and Dissertations
Wrong-way driving (WWD) is a dangerous behavior, especially on high-speed divided highways. The nature of WWD crashes makes it difficult for agencies to combat them effectively. Advanced WWD countermeasures equipped with flashing lights, detection devices, and cameras can significantly reduce WWD. However, these countermeasures' high costs mean that agencies often cannot deploy them at all exit ramps. To help agencies identify the most cost-effective deployment locations for advanced WWD countermeasures, an innovative WWD countermeasure optimization approach was developed. This approach consists of a WWD hotspots model and a WWD countermeasures optimization algorithm. The WWD hotspots model uses non-crash WWD events, …
Assessing The Impact Of Multi-Variate Steering-Rate Vehicle Control On Driver Performance In A Simulation Framework, Michael Xynidis
Assessing The Impact Of Multi-Variate Steering-Rate Vehicle Control On Driver Performance In A Simulation Framework, Michael Xynidis
Electronic Theses and Dissertations
When a driver turns a steering-wheel, he or she normally expects the vehicle's steering system to communicate an equivalent amount of signal to the road-wheels. This relationship is linear and occurs regardless of the steering-wheel's position within its rotational travel. The linear steering paradigm in passenger vehicles has gone largely unchanged since mass production of passenger vehicles began in 1901. However, as more electronically-controlled steering systems appear in conjunction with development of autonomous steering functions in vehicles, an opportunity to advance the existing steering paradigms arises. The following framework takes a human-factors approach toward examining and evaluating alternative steering systems …
A Joint Econometric Approach For Modeling Crash Counts By Collision Type, Tanmoy Bhowmik
A Joint Econometric Approach For Modeling Crash Counts By Collision Type, Tanmoy Bhowmik
Electronic Theses and Dissertations
In recent years, there is growing recognition that common unobserved factors that influence crash frequency by one attribute level are also likely to influence crash frequency by other attribute levels. The most common approach employed to address the potential unobserved heterogeneity in safety literature is the development of multivariate crash frequency models. The current study proposes an alternative joint econometric framework to accommodate for the presence of unobserved heterogeneity – referred to as joint negative binomial-multinomial logit fractional split (NB-MNLFS) model. Furthermore, the study undertakes a first of its kind comparison exercise between the most commonly used multivariate model (multivariate …
Use Of Accelerated Calcite Precipitation Method To Investigate Calcium Carbonate Precipitation From Recycled Concrete For Drainage System Applications, Toni Curate
Electronic Theses and Dissertations
Recycled concrete aggregate (RCA) is a sustainable construction material that is a viable option for use in drainage systems by replacing virgin aggregate. Replacing virgin aggregate with RCA is beneficial from both economic and environmental perspectives. However, the use of RCA as pipe backfill materials may cause a long-term performance issue such as potential clogging due to fines accumulation and calcite precipitation on filter fabric. Previous studies investigated the long-term performance of RCA regarding flow rate. Therefore, this study investigated calcite precipitation potential of RCA. The Accelerated Calcite Precipitation (ACP) procedure was devised and used to estimate "life-time" calcite precipitation …