Physical Sciences and Mathematics Commons^™

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, …

Wald Confidence Intervals For A Single Poisson Parameter And Binomial Misclassification Parameter When The Data Is Subject To Misclassification, Nishantha Janith Chandrasena Poddiwala Hewage

Electronic Theses and Dissertations

This thesis is based on a Poisson model that uses both error-free data and error-prone data subject to misclassification in the form of false-negative and false-positive counts. We present maximum likelihood estimators (MLEs), Fisher's Information, and Wald statistics for Poisson rate parameter and the two misclassification parameters. Next, we invert the Wald statistics to get asymptotic confidence intervals for Poisson rate parameter and false-negative rate parameter. The coverage and width properties for various sample size and parameter configurations are studied via a simulation study. Finally, we apply the MLEs and confidence intervals to one real data set and another realistic …

Frequency And Temperature Dependence Of Shear Wave Speed With Rheological Properties In A Micellar Fluid, E. G. Sunethra K. Dayavansha

Electronic Theses and Dissertations

Wormlike micellar fluids, which flow when subjected to long-term stresses, are mechanically viscoelastic over shorter durations and can support shear waves. These fluids are birefringent under shear, allowing the study of shear wave propagation using both optical and acoustic modalities. Microstructural phase transitions of the micelles are temperature dependent and can manifest as sharp changes in the shear wave speed as a function of temperature. In this work, the behavior of shear waves in a fluid consisting of hexadecyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSal) combined in a 5:3 ratio in a 200 mM concentration is studied. The temperature-dependent microstructural …

Analysis Of Nucleus Properties Of The Enigmatic Comet 29p/Schwassmann-Wachmann 1, Charles Schambeau

Electronic Theses and Dissertations

We present results from a continuing effort to understand activity drivers for the enigmatic Comet 29P/Schwassmann-Wachmann 1 (SW1). SW1 has been of interest since its discovery almost 100 years ago because of its nearly continuous, quiescent activity beyond the water-sublimation line and its highly variable, outburst activity while receiving a nearly constant insolation due to its low eccentricity orbit. These characteristics make SW1 a useful target for investigating both distant cometary activity drivers and also cometary outburst behavior. We approach answering these questions through a detailed analysis of SW1; first by measuring nucleus properties required for a more accurate nucleus …

Warning Confidence And Perceptions Of Lava Flow Hazard Diversion Strategies At Kīlauea And Mauna Loa Volcanoes, Hawai‘I, Ashleigh Reeves

Electronic Theses and Dissertations

The 2014-15 lava flow crisis at Kīlauea volcano, Hawai‘i and post-September 2015 elevated unrest at adjacent Mauna Loa volcano provided opportunities to assess households’ psychological and behavioral responses to different levels of volcanic activity. Weused the Protective Action Decision Model to examine stakeholder perceptions and confidence in warnings, in addition toattitudes toward lava flow mitigation strategies, such as diversion by berms and bombing, and people’s acceptance of additional risk to personal property in exchange for protecting important elements of their community, such as schools, major roads, electrical substation, and shopping centers. Respondents’ confidence in events important in decision-making during emergencies …

The 2-Domination Number Of A Caterpillar, Presley Chukwukere

Electronic Theses and Dissertations

A set D of vertices in a graph G is a 2-dominating set of G if every vertex in V − D has at least two neighbors in D. The 2-domination number of a graph G, denoted by γ₂(G), is the minimum cardinality of a 2- dominating set of G. In this thesis, we discuss the 2-domination number of a special family of trees, called caterpillars. A caterpillar is a graph denoted by P_k(x₁, x₂, ..., x_k), where x_i is the number of leaves attached to the ith vertex …

Distribution Of A Sum Of Random Variables When The Sample Size Is A Poisson Distribution, Mark Pfister

Electronic Theses and Dissertations

A probability distribution is a statistical function that describes the probability of possible outcomes in an experiment or occurrence. There are many different probability distributions that give the probability of an event happening, given some sample size n. An important question in statistics is to determine the distribution of the sum of independent random variables when the sample size n is fixed. For example, it is known that the sum of n independent Bernoulli random variables with success probability p is a Binomial distribution with parameters n and p: However, this is not true when the sample size …

3d-Printed Fluidic Devices And Incorporated Graphite Electrodes For Electrochemical Immunoassay Of Biomarker Proteins, Abdulhameed Alabdulwaheed

Electronic Theses and Dissertations

Biomarkers are measurable indicators of health status or disease state that can be used for diagnosis and may help guide patient treatment strategies. Enzyme-linked immunosorbent assays (ELISA) and other many clinical techniques currently used for measuring biomarker proteins lack sensitivity, demand high analysis cost, are often not well-suited for measuring multiple biomarkers in a single sample, and require long analysis times. Here, we demonstrate simple, low-cost 3D-printed flow-through devices with integrated electrodes modified with gold nanoparticles (AuNPs) for electrochemical immunoassays of S100B, a biomarker protein related to conditions like skin cancer and brain injuries. Flow-through devices are fabricated from photocurable-resin …

Synthesis And Characterization Of Zinc(Ii) Dipyrrin Photosensitizers, Norah Alqahtani

Electronic Theses and Dissertations

Photocatalytic carbon dioxide reduction transforms CO2 to useful chemicals and fuels, reducing CO2 emissions and making fossil fuels more renewable. Due to a lack of earthabundant sensitizers, we want to design new earth-abundant sensitizers to go with the many known carbon dioxide reduction catalysts. Zn(II) dipyrrin complexes strongly absorb visible light, but their excited state properties have not been widely studied. To investigate their photophysical properties, two Zn dipyrrin complexes, with and without heavy atoms, were synthesized and characterized by NMR and mass spectrometry. The photophysical properties of the two complexes were measured in polar and non-polar solvents, particularly fluorescence …

Novel Relative Spontaneous Ignition Temperature Determination Using Carbon Dioxide Onset With Sta/Ir, Antonio David Trevino

Electronic Theses and Dissertations

Simultaneous thermal analysis, coupled with infrared spectroscopy (STA/IR), was utilized to monitor the evolution of gaseous products during the thermal degradation of samples from Triadica sebifera (Chinese tallow), Ligustrum sinense (Chinese privet), and Ilex vomitoria (yaupon) plants. Identification of carbon dioxide was successful with a spectral match of 90.2 percent and further used in the determination of relative spontaneous ignition temperature, or RSIT. The RSIT value during the growing season for Chinese tallow, Chinese tallow stem, Chinese privet, and Yaupon were 208.4°C, 250.3°C, 210.1°C, and 232.3°C respectively. During the dormant seasons, the values for Chinese tallow stem, Chinese privet, and …

High Dynamic Range Optical Devices And Applications., Elijah Robert Jensen

Electronic Theses and Dissertations

Much of what we know about fundamental physical law and the universe derives from observations and measurements using optical methods. The passive use of the electromagnetic spectrum can be the best way of studying physical phenomenon in general with minimal disturbance of the system in the process. While for many applications ambient visible light is sufficient, light outside of the visible range may convey more information. The signals of interest are also often a small fraction of the background, and their changes occur on time scales so quickly that they are visually imperceptible. This thesis reports techniques and technologies developed …

Developments In Multivariate Post Quantum Cryptography., Jeremy Robert Vates

Electronic Theses and Dissertations

Ever since Shor's algorithm was introduced in 1994, cryptographers have been working to develop cryptosystems that can resist known quantum computer attacks. This push for quantum attack resistant schemes is known as post quantum cryptography. Specifically, my contributions to post quantum cryptography has been to the family of schemes known as Multivariate Public Key Cryptography (MPKC), which is a very attractive candidate for digital signature standardization in the post quantum collective for a wide variety of applications. In this document I will be providing all necessary background to fully understand MPKC and post quantum cryptography as a whole. Then, I …

Information Theoretic Thresholding Techniques Based On Particle Swarm Optimization., Surina Surina

Electronic Theses and Dissertations

In this dissertation, we discuss multi-level image thresholding techniques based on information theoretic entropies. In order to apply the correlation information of neighboring pixels of an image to obtain better segmentation results, we propose several multi-level thresholding models by using Gray-Level & Local-Average histogram (GLLA) and Gray-Level & Local-Variance histogram (GLLV). Firstly, a RGB color image thresholding model based on GLLA histogram and Tsallis-Havrda-Charv'at entropy is discussed. We validate the multi-level thresholding criterion function by using mathematical induction. For each component image, we assign the mean value from each thresholded class to obtain three segmented component images independently. Then we …

Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor

Electronic Theses and Dissertations

Metabolomics, the study of small molecules in biological systems, has enjoyed great success in enabling researchers to examine disease-associated metabolic dysregulation and has been utilized for the discovery biomarkers of disease and phenotypic states. In spite of recent technological advances in the analytical platforms utilized in metabolomics and the proliferation of tools for the analysis of metabolomics data, significant challenges in metabolomics data analyses remain. In this dissertation, we present three of these challenges and Bayesian methodological solutions for each. In the first part we develop a new methodology to serve a basis for making higher order inferences in metabolomics, …

Generalized Spatiotemporal Modeling And Causal Inference For Assessing Treatment Effects For Multiple Groups For Ordinal Outcome., Soutik Ghosal

Electronic Theses and Dissertations

This dissertation consists of three projects and can be categorized in two broad research areas: generalized spatiotemporal modeling and causal inference based on observational data. In the first project, I introduce a Bayesian hierarchical mixed effect hurdle model with a nested random effect structure to model the count for primary care providers and understand their spatial and temporal variation. This study further enables us to identify the health professional shortage areas and the possible impacting factors. In the second project, I have unified popular parametric and nonparametric propensity score-based methods to assess the treatment effect of multiple groups for ordinal …

Plasma Based Synthesis And Surface Modification Of Graphene., Rong Zhao

Electronic Theses and Dissertations

Graphene, an atom thick layer of carbon, has attracted intense scientific interest due to its exceptional electrical, mechanical and chemical properties. Especially, it provides a perfect platform to explore the unique electronic properties in absolute two-dimension. Pristine graphene possesses zero band gap and weakens its competitiveness in the field of semiconductors. In order to induce a band gap and control its semiconducting properties, functionalization and doping are two of the most feasible methods. In the context of functionalization, large area monolayer graphene synthesized by chemical vapor deposition was subjected to controlled and sequential fluorination using radio frequency plasma while monitoring …

Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller

Electronic Theses and Dissertations

The inherent heterogeneity of tumor tissue presents a major challenge to nanoparticle-medicated drug delivery. This heterogeneity spans from the molecular to the cellular (cell types) and to the tissue (vasculature, extra-cellular matrix) scales. Here we employ computational modeling to evaluate therapeutic response as a function of vascular-induced tumor tissue heterogeneity. Using data with three-layered gold nanoparticles loaded with cisplatin, nanotherapy is simulated with different levels of tissue heterogeneity, and the treatment response is measured in terms of tumor regression. The results show that tumor vascular density non-trivially influences the nanoparticle uptake and washout, and the associated tissue response. The drug …

Immobilization Of Gold Nanoparticles On Nitrided Carbon Fiber Ultramicroelectrodes By Direct Reduction, George Affadu-Danful

Electronic Theses and Dissertations

Due to enhanced properties such as large surface area-to-volume ratio, metal nanoparticles are often employed as catalysts for various applications. However, most studies involving nanoparticle catalysts have been conducted on collections of particles rather than single nanoparticles. Results obtained for ensemble systems can be difficult to interpret due to variations in particle loading and interparticle distance, which are often challenging to control and characterize. In this study, two immobilization strategies for incorporating gold nanoparticles (AuNPs) on carbon fiber ultramicroelectrodes (UMEs) were compared with the goal of extending these techniques to nanoelectrodes for studies of single AuNPs. Both layer-by-layer deposition of …

Hydrodynamic Drivers Of Dissolved Oxygen Variability Within A Highly Developed Tidal Creek In Myrtle Beach, South Carolina, Douglas Matthew Pastore

Electronic Theses and Dissertations

Erosion and water quality degradation have been observed in Singleton Swash in Myrtle Beach, SC, and have been hypothesized to be related to migration of the beach-face channel. Dredging this channel temporarily fixes erosional threats to nearby infrastructure but the effects on water quality are not well understood. It is hypothesized that variations in dissolved oxygen (DO) concentration (used here as a proxy for water quality) within the water column are related to changes in vertical mixing and transport due to oceanic tidal forcing. This study utilizes current meters, pressure sensors, and optical DO probes to measure and study the …

Seasonal Occurrence, Relative Abundance, And Migratory Movements Of Juvenile Sandbar Sharks, Carcharhinus Plumbeus, In Winyah Bay, South Carolina, Caroline Collatos

Electronic Theses and Dissertations

Winyah Bay, located on the coast of South Carolina, is the fourth largest U.S. estuary by discharge rate (Voulgaris et al. 2002), and provides an annually used habitat for juvenile C. plumbeus (Abel et al. 2006, Gary 2009). From May to September 2016 and 2017, we set a total of 303 bottom longlines in middle and lower Winyah Bay to assess sex ratios, size distributions, and catch per unit effort (CPUE), as well as the potential influence of abiotic parameters on CPUE. A subset of eleven juvenile C. plumbeus was tagged with VEMCO (V16-4H) acoustic transmitters to analyze seasonal occurrence, …

Holocene Formation History Of Mud Depocenters On The Continental Shelf In The Gulf Of Cadiz, Southwestern Spain, Mary Lee King

Electronic Theses and Dissertations

Holocene mud accumulation on the continental shelf in northern Gulf of Cadiz, from the Guadalquivir River to the Tinto-Odiel Estuary, is described as two types of mud depocenters (MDCs): a sheet-like prodelta and mud belt. Despite a substantial number of investigations of this continental shelf (Somoza et al., 1997; Hernández-Molina et al., 2000; Lobo et al., 2001; synthesis: Lobo et al., 2015), information on Holocene sediment facies and a robust stratigraphic age model remained unestablished (Lobo et al., 2002; and Lobo and Ridente, 2014). Objectives of this study are to describe the dynamics of MDC formation in a chrono- and …

Semi-Quantitative Assessment On Winyah Bay's Microplastic Contamination Levels, Samantha Ladewig

Electronic Theses and Dissertations

Although there is much concern globally regarding microplastic contamination in aquatic environments, there is little documentation on microplastic contamination concentrations within South Carolina inland waters and coastal areas. Specifically, Winyah Bay, SC should be of high priority for microplastic contamination evaluations as it is the third largest drainage basin (47,060 km2) and the second largest (157 km2) estuarine system on the east coast of the United States. Today, the general influencing physical factors on microplastic transport are mostly known by the scientific community, however, transport and deposition patterns of microplastics heavily vary by location depending on various physical, chemical, and …

Impact Of Data Selection On The Accuracy Of Atmospheric Refractivity Inversions Performed Over Marine Surfaces, Ian Joseph Matsko

Electronic Theses and Dissertations

Within the Earth’s atmosphere there is a planetary boundary layer that extends from the surface to roughly 1 km above the surface. Within this planetary boundary layer exists the marine atmospheric boundary layer, which is a complex turbulent surface layer that extends from the sea surface to roughly 100 m in altitude. The turbulent nature of this layer combined with the interactions across the air-sea interface cause ever changing environmental conditions within it, including atmospheric properties that affect the index of refraction, or atmospheric refractivity. Variations in atmospheric refractivity lead to many types of anomalous propagation phenomena of electromagnetic (EM) …

Hardbottom Characterization And Relationship To The Geologic Framework In Long Bay, South Carolina, Cathryn J. Wheaton

Electronic Theses and Dissertations

Hardbottom seafloor is a common element among sediment-starved portions of the inner continental shelf along the U.S. Atlantic margin. These areas are characterized by indurated sediment surfaces that are heavily altered by biological and physical processes. Long Bay, in northeastern South Carolina, offers ideal environmental conditions for hardbottom exposure with only patchy Holocene sand deposits, interspersed with extensive hardbottom areas. Here we use high-resolution multibeam bathymetry, CHIRP subbottom profiling and electrical resistivity data, along with surficial sediment samples, hardbottom thin sections, and water column radioisotope (radon-222) analysis to investigate the origin and geologic framework of a region of hardbottom seafloor …

Steric Effects Of Alkyl Ammonium Salts On The Combustion Of Exchanged Smectite Clays, Celeste A. Keith

Electronic Theses and Dissertations

Bomb calorimetry was explored as a new method for determining the cation exchange capacity (CEC) of clays. Smectite clays were modified with several alkyl ammonium salts varying in number of carbons and the spatial orientation of the carbons about the central nitrogen atom. The clays used, standards purchased from the Source Clay Repository, have CECs of 44, 80, 88, and 120 meq/100 g. Theoretically, the combustion energy of the organo-clays should be approximately the same for each salt. Any differences in energy would be due to the different structures of the salts and how they are oriented in the interlamellar …

Speleogenetic Evolution And Geological Remote Sensing Of The Gypsum Plain, Eddy County, New Mexico, Jessica Shields

Electronic Theses and Dissertations

Permian evaporites of the Gypsum Plain region of the Delaware Basin host extensive karst phenomena, as well as unique diagenetic alterations of host strata. Because of the complex, poorly understood hydrogeologic system, little has been established concerning the relation and evolution of the overprinted, modern and ancient karst manifestations within the Gypsum Plain, as a whole. Through a combination of traditional field studies and the development of improved remote sensing methodologies, this study established the speleogenetic evolution of the Gypsum Plain in relation to the greater tectonic, stratigraphic, hydrogeologic and climatic history of the Delaware Basin. Emphasis was focused on …

A Geophysical Delineation Of A Normal Fault Within The Gulf Coastal Plain, Montgomery County, Texas, Danielle Minteer

Electronic Theses and Dissertations

The Gulf Coast of Texas has been a known hydrocarbon basin for many years with various structural trapping mechanisms such as anticlines, faults and salt domes. While most large salt domes have been extensively studied in the Gulf Coastal Plain, many smaller normal faults have not been studied in detail. This research study employs an integrated geophysical approach to mapping the Big Barn fault in Montgomery County, Texas. This fault is located on the Gulf Coastal Plain and is approximately 20 miles north of Houston, Texas. Most normal faults in the Gulf Coastal Plain formed as a result of the …

Developmental Mathematics: A Quantitative Investigation Of Instructor Classification As Related To Student Success, Brittany A. Fish

Electronic Theses and Dissertations

The purpose of this quantitative study was to examine what type of predictive power exists between an instructor’s employment classification, student gender, student race, and first-generation status on a student’s academic success in developmental mathematics, as measured by final semester grades at a regionally comprehensive state university in Texas between fall 2013 and spring 2017. Data were collected from the institution under study and the sample population included 1932 unique student observations. The data collected in this study were analyzed through a binary logistic regression model to determine whether an instructor’s employment classification, student gender, student race, and first-generation status …

Environmental Assessment Of Road Brining And Injection Wells For Disposal Of Oil And Gas Liquid Waste, Marissa Madia

Electronic Theses and Dissertations

The dramatic increase in oil and gas drilling operations in Pennsylvania over the last decade has presented a challenge for their wastewater disposal (e.g., flowback, produced water). Currently, these fluids are treated in permitted brine treatment plants or exported out of state to deep injection well facilities. In Pennsylvania, road brining for dust control is permitted for conventional well brines, and permits for three injection wells for unconventional brines are pending. This study focused on water quality impacts due to road brining in Farmington Township (45 samples) and ground and surface water in Grant Township (41 samples) prior to the …

A Computational Model Of Team-Based Dynamics In The Workplace: Assessing The Impact Of Incentive-Based Motivation On Productivity, Josef Di Pietrantonio

Electronic Theses and Dissertations

Large organizations often divide workers into small teams for the completion of essential tasks. In an effort to maximize the number of tasks completed over time, it is common practice for organizations to hire workers with the highest level of education and experience. However, despite capable workers being hired, the ability of teams to complete tasks may suffer if the workers' individual motivational needs are not satisfied.

To explore the impact of incentive-based motivation on the success of team-based organizations, we developed an agent-based model that stochastically simulates the proficiency of 100 workers with varying abilities and motive profiles to …