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Development Of A Computational Application To Aid With Chemometric And Forensic Analysis Of Fire Debris Samples, Michelle Corbally Jan 2022

Development Of A Computational Application To Aid With Chemometric And Forensic Analysis Of Fire Debris Samples, Michelle Corbally

Electronic Theses and Dissertations, 2020-2023

Fire debris analysis is a forensic science discipline that determines if an ignitable liquid residue is present or absent in a fire debris sample. Currently, fire debris analysis results in categorical statements based on qualitative data, not the quantitative evidentiary value of data. The purpose of this research was to develop a novel software application to aid fire debris analysts in the identification and classification of ignitable liquid residues that are found in fire debris samples. The developed application uses target factor analysis (TFA) and Pearson correlation for compound identification in gas chromatograms using mass spectral comparison and allows for …

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Development Of Holographic Phase Masks For Wavefront Shaping, Nafiseh Mohammadian Jan 2022

Development Of Holographic Phase Masks For Wavefront Shaping, Nafiseh Mohammadian

Electronic Theses and Dissertations, 2020-2023

This dissertation explores a new method for creating holographic phase masks (HPMs), which are phase transforming optical elements holographically recorded in photosensitive glass. This novel hologram recording method allows for the fast production of HPMs of any complexity, as opposed to the traditional multistep process, which includes the design and fabrication of a master phase mask operating in the UV region before the holographic recording step. We holographically recorded transmissive HPMs that are physically robust (they are recorded in a silicate glass volume), can handle tens of kilowatts of continuous wave (CW) laser power, are un-erasable, user defined, require no …

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Characterizing The Particle Size Distribution In Saturn's Rings Using Cassini Uvis Stellar Occultation Data, Stephanie Eckert Jan 2022

Characterizing The Particle Size Distribution In Saturn's Rings Using Cassini Uvis Stellar Occultation Data, Stephanie Eckert

Electronic Theses and Dissertations, 2020-2023

NASA's Cassini mission to Saturn revolutionized modern understanding of the planet's vast and intricate ring system. We use stellar occultation data from Cassini's UVIS High Speed Photometer (HSP) to characterize the particle size distribution in the rings with two methods. First, we discern the sizes of the smallest particles at ring edges by forward-modeling observed diffraction signatures which appear as spikes in the signal, the shape and amplitude of which depends on the size and abundance of the smallest particles. We then probe the upper end of the size distribution using occultation statistics. Although the distribution of photon counts in …

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Reticular Design And Synthesis Of Metal-Organic Frameworks With Targeted Emergent Properties, David Fairchild Jan 2022

Reticular Design And Synthesis Of Metal-Organic Frameworks With Targeted Emergent Properties, David Fairchild

Electronic Theses and Dissertations, 2020-2023

The research presented in this dissertation describes the design and synthesis of substitutional-solid-solution-based multivariate metal-organic frameworks (SSS-based MTV MOFs) with functionalized organic linkers to study their emergent properties in the crystalline solid state. The synthetic versatility and tunability of organic chemistry coupled with the predictable organization of inorganic structures enables MTV MOF systems to further the fundamental understanding of structure-composition-property relationships for the targeted design of applied materials due to their ability to control the structure, composition, and property independently. To begin, a set of terphenyl linkers with varied steric and electronic properties were crystallized as a family of UiO-type …

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Control Of Coherence In Attosecond Atomic Ionization, Saad Mehmood Jan 2022

Control Of Coherence In Attosecond Atomic Ionization, Saad Mehmood

Electronic Theses and Dissertations, 2020-2023

The motion of electrons in atoms, molecules, and in condensed matter unfolds on a time scale from the attosecond (1 as = 10-18 s) to several femtoseconds (1 fs= 10-15 s). The advent of attosecond light pulses has opened the way to the time-resolved study of electronic motion and of ionization processes using pump-probe spectroscopy. In this thesis, we examine three aspects of the ionization dynamics in poly-electronic atoms: i) the coherence of the emerging charged fragments, ii) two-photon ionization pathways, and iii) the reconstruction of photoionization amplitudes from experimental observable. We focus on the role of autoionizing states and …

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Heat Transfer Characterization Of Carbon Dioxide In Micro Impinging Jet(S) Near Critical Conditions, Stephen Adeoye Jan 2022

Heat Transfer Characterization Of Carbon Dioxide In Micro Impinging Jet(S) Near Critical Conditions, Stephen Adeoye

Electronic Theses and Dissertations, 2020-2023

The continuous growth and demand of increased operating performances of electronics has brought about an increase in the chip power density posing threat to the thermal management of these devices. Although numerous thermal solutions ranging from passive to active cooling together with a variety of working fluids have been adopted, however, the question whether these available cooling methods could meet up with the ever-growing need for increased operating performances is a concerning one. Jet impingement cooling has been effectively used in many industrial applications due to its high heat transfer capability. The limited study at the micro scale suggests that …

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Applications For Machine Learning On Readily Available Data From Virtual Reality Training Experiences, Alec Moore Jan 2022

Applications For Machine Learning On Readily Available Data From Virtual Reality Training Experiences, Alec Moore

Electronic Theses and Dissertations, 2020-2023

The purpose of the research presented in this dissertation is to improve virtual reality (VR) training systems by enhancing their understanding of users. While the field of intelligent tutoring systems (ITS) has seen value in this approach, much research into making use of biometrics to improve user understanding and subsequently training, relies on specialized hardware. Through the presented research, I show that with machine learning (ML), the VR system itself can serve as that specialized hardware for VR training systems. I begin by discussing my explorations into using an ecologically valid, specialized training simulation as a testbed to predict knowledge …

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Cholera Transmission Dynamic Model With Environmental Impacts Of Plankton Reservoirs, Sweety Sarker Jan 2022

Cholera Transmission Dynamic Model With Environmental Impacts Of Plankton Reservoirs, Sweety Sarker

Electronic Theses and Dissertations, 2020-2023

Cholera is an acute disease that is a global threat to the world and can kill people within a few hours if left untreated. In the last 200 years, seven pandemics occurred, and, in some countries, it remains endemic. The World Health Organization (WHO) declared a global initiative to prevent cholera by 2030. Cholera dynamics are contributed by several environmental factors such as salinity level of water, water temperature, presence of plankton especially zooplankton such as cladocerans, rotifers, copepods, etc. Vibrio cholerae (V. cholerae) bacterium is the main reason behind the cholera disease and the growth of V. cholerae depends …

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Atmospheric Retrieval: Bayesian Methods, Machine Learning, And Application To Exoplanets, Michael Himes Jan 2022

Atmospheric Retrieval: Bayesian Methods, Machine Learning, And Application To Exoplanets, Michael Himes

Electronic Theses and Dissertations, 2020-2023

Atmospheric retrieval is the inverse modeling method where atmospheric properties are constrained based on measured spectra. Due to the low signal-to-noise ratios of exoplanet observations, exoplanetary retrieval codes pair a radiative transfer (RT) simulator with a Bayesian statistical framework in order to characterize the distribution of atmospheric parameters that could explain the observations (the posterior distribution). This requires on the order of 106 RT model evaluations, which requires hours to days of compute time depending on model complexity. In this work, I investigate atmospheric retrieval methods and apply them to observations of hot Jupiters. Chapter 2 presents a set of …

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Design And Mechanical Characterization Of Functionally Graded Sandwich Beams Fabricated Via Additive Manufacturing, Timothy Grondin Jan 2022

Design And Mechanical Characterization Of Functionally Graded Sandwich Beams Fabricated Via Additive Manufacturing, Timothy Grondin

Electronic Theses and Dissertations, 2020-2023

Lightweight aerospace structures have been sought after since humans took flight in 1903, making major strides in NASA's pursuit of the moon with the development of sandwich panel composites. Sandwich structures typically consist of two stiff phases (i.e., face sheets) separated by a lightweight phase (i.e., core), which are stacked together through adhesive layers. Such a structural arrangement provides a high stiffness-to-weight ratio and is often used in applications where weight saving is critical. Functionally Graded Materials (FGMs), refer to multifunctional materials, which contain a spatial variation of composition and/or microstructure for the specific purpose of altering thermal and structural …

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Uncovering Ophelia: The Reclamation Of Women's Madness Through Feminist Disability Studies, Amy Crawford Jan 2022

Uncovering Ophelia: The Reclamation Of Women's Madness Through Feminist Disability Studies, Amy Crawford

Electronic Theses and Dissertations, 2020-2023

In his essay "The Philosophy of Composition," Edgar Allan Poe proclaims that "the death of a beautiful woman is unquestionably the most poetical topic in the world," and this sentiment remains curiously persistent within the literary world. Artists have looked towards their beautiful muses for centuries as a source of inspiration and introspection, and the faces that these muses wear were often swooning, longing, or even dead. Nineteenth-century British aesthetics solidified a gendered ideology that remains prevalent to this day; in particular, one subculture of Victorian aesthetics that emerged during this period was the Cult of Ophelia: a collection of …

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Polymer Derived Ceramic For Lithium-Ion Storage, And Electrospun Polyelectrolyte Fiber For Heavy Metal Ions Removal, Zeyang Zhang Jan 2022

Polymer Derived Ceramic For Lithium-Ion Storage, And Electrospun Polyelectrolyte Fiber For Heavy Metal Ions Removal, Zeyang Zhang

Electronic Theses and Dissertations, 2020-2023

This dissertation includes two major projects. The first project investigated the great potential of polymer-derived ceramics (PDCs) as lithium-ion battery anode materials with good cycling stability and large capacity. SiCNO ceramic nanoparticles were produced by pyrolysis of polysilazane nanoparticles synthesized via an oil-in-oil emulsion crosslinking. The SiCNO nanoparticles had an average particle size of around 9 nm and contained graphitic carbon, Si3N4, and SiO2 domains. The electrochemical behavior of SiCNO nanoparticles anode was investigated to evaluate the Li-ion storage performance and understand its mechanism of Li-ion storage. The lithiation of SiCNO was observed at ~0.385 V versus Li/Li+. The anode …

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Characterization Of A Malachite Green Dna Aptamer And Development Of Malachite Green Dna Aptamer Sensor, Martin O'Steen Jan 2022

Characterization Of A Malachite Green Dna Aptamer And Development Of Malachite Green Dna Aptamer Sensor, Martin O'Steen

Electronic Theses and Dissertations, 2020-2023

Hydrogels have been extensively studied for use in applications such as tissue engineering, drug delivery systems, wound dressing, actuators, valves, and sensors in Micromechanical Systems (MEMS), among others. Thermo-responsive hydrogels in particular pose various advantages such as their capability to respond to an external stimulus and reverse the response when the stimulus is removed and the ability to imbibe a significant amount of solvent and increase their volume by over 1000%. Extensive research has been conducted to tune and improve hydrogel's rate and degree of swelling and mechanical properties. Previous work showed that when synthetic clay (Laponite) is cross-linked with …

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An Econometric Analysis Of Domestic Aviation In The Us, Sudipta Dey Tirtha Jan 2022

An Econometric Analysis Of Domestic Aviation In The Us, Sudipta Dey Tirtha

Electronic Theses and Dissertations, 2020-2023

In this dissertation, we examine two dimensions of domestic aviation - demand and delay - that directly influence economic impact of the sector. We conduct a comprehensive analysis of airline demand employing airline data compiled by Bureau of Transportation Statistics. The demand analysis is conducted in three steps. First, we propose a novel modeling approach for modeling airline demand evolution over time. Specifically, we develop a joint panel group generalized ordered probit (GGOP) model system for modeling air passenger arrivals and departures in a discretized framework that subsumes the traditional linear regression approach. Further, we consider the influence of observed …

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A Unified Tool For Adaptive Collocation Techniques Applied To Solving Optimal Control Problems, Bethany Kelly Jan 2022

A Unified Tool For Adaptive Collocation Techniques Applied To Solving Optimal Control Problems, Bethany Kelly

Electronic Theses and Dissertations, 2020-2023

In this work, a user-friendly MATLAB tool is introduced to solve nonlinear optimal control problems by applying collocation techniques using Coupled Radial Basis Functions (CRBFs). CRBFs are a new class of Radial Basis Functions combined with a conical spline r^5, which provides the advantage of insensitivity to the shape parameter while maintaining accuracy and robustness. To solve optimal control problems, software tools are often employed to implement numerical methods and apply advanced techniques to solving differential equations. Although several commercial software tools exist for solving optimal control problems, such as ICLOCS2, GPOPS, and DIDO, there are no options available that …

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Mathematical Model For Giraffe Population Dynamics, Huntir Bass Jan 2022

Mathematical Model For Giraffe Population Dynamics, Huntir Bass

Electronic Theses and Dissertations, 2020-2023

Since the 1980s the overall giraffe population has dropped at least 40% causing some researchers to label this rapid decline as the "Silent Extinction." Due to this plummet, understanding the behaviors of the giraffe population is absolutely necessary before they are on the brink of extinction. Through the usage of mathematical modeling methodologies, a general model is created to illustrate the relationship between juvenile and adult female giraffes through numerous interaction parameters. Variations on specific variables generate different simulations, which allows more biological accuracy. With each variation having an established coexistence equilibrium between the juvenile and adult female populations, the …

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Various Dynamical Regimes, And Transitions From Homogeneous To Inhomogeneous Steady States In Nonlinear Systems With Delays And Diverse Couplings, Ryan Roopnarain Jan 2022

Various Dynamical Regimes, And Transitions From Homogeneous To Inhomogeneous Steady States In Nonlinear Systems With Delays And Diverse Couplings, Ryan Roopnarain

Electronic Theses and Dissertations, 2020-2023

This dissertation focuses on the effects of distributed delays modeled by 'weak generic kernels' on the collective behavior of coupled nonlinear systems. These distributed delays are introduced into several well-known periodic oscillators such as coupled Landau-Stuart and Van der Pol systems, as well as coupled chaotic Van der Pol-Rayleigh and Sprott systems, for a variety of couplings including diffusive, cyclic, or dynamic ones. The resulting system is then closed via the 'linear chain trick' and the linear stability analysis of the system and conditions for Hopf bifurcations that initiate oscillations are investigated. A variety of dynamical regimes and transitions between …

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Methods And Characterization Of Topological And Disordered-Induced Protection Of Coherence In Quantum Systems, Sayandip Dhara Jan 2022

Methods And Characterization Of Topological And Disordered-Induced Protection Of Coherence In Quantum Systems, Sayandip Dhara

Electronic Theses and Dissertations, 2020-2023

Quantum computers can efficiently simulate natural processes and solve certain types of mathematical problems. Two of the key issues preventing the development of platforms to realize a scalable quantum machine are the decoherence of the qubits due to the interaction with the environment and the existence of a large overhead to correct errors. Although there already exist noisy intermediate-scale quantum machines, we still need to improve much to be able to solve problems faster than the already existing classical computers. In this dissertation, we explore two approaches to tackle both issues. We propose a scheme where, using quasi-Majorana zero modes …

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Analysis And Characterization Of Smokeless Powders And Smokeless Powder Residues, Emily Lennert Jan 2022

Analysis And Characterization Of Smokeless Powders And Smokeless Powder Residues, Emily Lennert

Electronic Theses and Dissertations, 2020-2023

The ability to associate a smokeless powder, smokeless powder residue, or organic gunshot residue (OGSR) to one another may be helpful in determining the origin of a suspected sample and aid in linking a suspect to a crime scene. In this study, smokeless powders were extracted and analyzed via gas chromatography – mass spectrometry (GC-MS) and direct analysis in real time – high resolution mass spectrometry (DART-HRMS). Subsequently, group definition was performed using hierarchical cluster analysis and principal component analysis followed by internally validated classification models. Then, smokeless powder residues were generated in-lab and extracted. Resulting residue data from each …

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Methodology Of Augmented Reality Chinese Language Articulatory Pronunciation Practice: Game And Study Design, Daria Sinyagovskaya Jan 2022

Methodology Of Augmented Reality Chinese Language Articulatory Pronunciation Practice: Game And Study Design, Daria Sinyagovskaya

Electronic Theses and Dissertations, 2020-2023

Learning a language can be hard. Learning a language that contains tones to convey meaning is even harder. This dissertation presents a novel methodology for creating a language practice using augmented reality that has never been used before. The design of a new app in AR and non-AR versions can evaluate the same practice methodology. This methodology was applied to new software and was examined in regard to the importance of this software. Although the study results are inconclusive, progress has been made in answering research questions on the effectiveness of AR versus non-AR and the reliability of peer assessment. …

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High Fidelity Injury Severity Analysis Using Econometric Modeling Approaches, Ahmed Kabli Jan 2022

High Fidelity Injury Severity Analysis Using Econometric Modeling Approaches, Ahmed Kabli

Electronic Theses and Dissertations, 2020-2023

Crash severity models are typically developed using police reported injury severity databases. However, several research studies have identified various challenges associated with police reported data. Therefore, the current dissertation is focusing on developing high resolution crash severity models based on medical professional driver injury severity reported using Abbreviated Injury Scale for eight body regions. The dissertation focused on developing a disaggregate injury severity modeling framework that can enhance the estimation accuracy of independent variable impacts on severity. Within this broad research vision, the dissertation has multiple objectives. First, a joint random parameters multivariate model structure with as many dimensions as …

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Shape Parameter & Nodal Distribution Insensitive Radial Basis Functions For Nonlinear Optimal Control Problems, Ahmed Elsadek Ahmed Elshafee Seleit Jan 2022

Shape Parameter & Nodal Distribution Insensitive Radial Basis Functions For Nonlinear Optimal Control Problems, Ahmed Elsadek Ahmed Elshafee Seleit

Electronic Theses and Dissertations, 2020-2023

Computational optimal control relies mainly on pseudospectral methods. The use of Chebyshev and Legendre polynomials is ubiquitous in the literature. This family of methods has good accuracy characteristics but constraints the nodal distribution to a certain grid that is denser at the boundaries. In this work, a set of novel Coupled Radial Basis Functions (CRBFs) is introduced as an approximation means for the nonlinear optimal control problem. CRBFs are real-valued Radial Basis Functions (RBFs) augmented with a conical spline. They do not require a specific nodal distribution. A plethora of research articles were published on the optimization of the shape …

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Reverse Engineering Of Adversarial Samples By Leveraging Patterns Left By The Attacker, Rahul Ambati Jan 2022

Reverse Engineering Of Adversarial Samples By Leveraging Patterns Left By The Attacker, Rahul Ambati

Electronic Theses and Dissertations, 2020-2023

Intrinsic susceptibility of deep learning to adversarial examples has led to a plethora of attack techniques with a common broad objective of fooling deep models. However, we find slight compositional differences between the algorithms achieving this objective. These differences leave traces that provide important clues for attacker profiling in real-life scenarios. Inspired by this, we introduce a novel problem of 'Reverse Engineering of aDversarial attacks' (RED). Given an adversarial example, the objective of RED is to identify the attack used to generate it. Under this perspective, we can systematically group existing attacks into different families, leading to the sub-problem of …

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An Examination Of Florida's High Stakes Testing: A Post-Hoc Study Of The Academic Achievement Of Students With Borderline Intellectual Functioning, Rhonda Mcmahon Jan 2022

An Examination Of Florida's High Stakes Testing: A Post-Hoc Study Of The Academic Achievement Of Students With Borderline Intellectual Functioning, Rhonda Mcmahon

Electronic Theses and Dissertations, 2020-2023

This study compares achievement of students with borderline intellectual functioning by investigating differences in Florida Standards Assessment results for those who received special education services and those who did not receive services. A review of the literature finds research focused on this population is limited with few effective strategies identified to help these students keep pace with the increasing demand of today's classrooms. This post-hoc causal-comparative study uses an analysis of variance to determine if there are statistically significant achievement differences in Florida Standards Assessment results in English Language Arts and Mathematics for students when examining the effect of the …

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Osiris-Rex Surface Imaging To Constrain Properties Of The Asteroid (101955) Bennu, Alicia Allen Jan 2022

Osiris-Rex Surface Imaging To Constrain Properties Of The Asteroid (101955) Bennu, Alicia Allen

Honors Undergraduate Theses

This study used images taken from the OSIRIS-REx spacecraft sample-return mission and projected onto a three-dimensional shape model to determine surface properties of the asteroid (101955) Bennu. Two major projects were completed. For the first project, images of the pre-sampled Nightingale site and post-sampled Nightingale were compared to determine how the TAGSAM sampling maneuver effected the surface of the asteroid directly at the sampling site and in the surrounding area. This analysis demonstrated how spacecraft can potentially affect a small body during this and future sample-return missions. For the second project, several craters on Bennu’s surface were selected and all …

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The Effect Of Technological Advancements On Interactions In The Agricultural Commodities Market, Savannah B. Armas Jan 2022

The Effect Of Technological Advancements On Interactions In The Agricultural Commodities Market, Savannah B. Armas

Honors Undergraduate Theses

The objective of this research is to find, if and how, real and financial technological advancements influence interactions in the agricultural commodities market. Statistical testing was conducted to identify potential correlation and any positive linear relationships in the price data between agricultural commodities and their complementary agricultural chemical producers. Testing if higher trade volumes in this industry result from higher technology usage were initiated by identifying shared linear growth between general index volumes and agricultural commodities, alongside their chemical complement stock volumes. The scientific development of chemical engineering mirrors financial technologies influencing trader behavior as a significant contributor to agricultural …

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Multicolor Ramsey And List Ramsey Numbers For Double Stars, Jake Ruotolo Jan 2022

Multicolor Ramsey And List Ramsey Numbers For Double Stars, Jake Ruotolo

Honors Undergraduate Theses

The core idea of Ramsey theory is that complete disorder is impossible. Given a large structure, no matter how complex it is, we can always find a smaller substructure that has some sort of order. For a graph H, the k-color Ramsey number r(H; k) of H is the smallest integer n such that every k-edge-coloring of Kn contains a monochromatic copy of H. Despite active research for decades, very little is known about Ramsey numbers of graphs. This is especially true for r(H; k) when k is at least 3, also known as the multicolor Ramsey number of …

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Self-Assessment Of Elementary Lesson Plans Through An Ecological Lens, Scott Edward Sebree Jan 2022

Self-Assessment Of Elementary Lesson Plans Through An Ecological Lens, Scott Edward Sebree

Honors Undergraduate Theses

Classrooms are ecosystems. Classrooms have well defined boundaries and host living and nonliving elements. These elements interact as classroom lessons and day to day ongoings occur. These interactions have potential to be synergized to increase learning outcomes. The purpose of this research is to develop a self-reflective instrument for teachers to consider the elements, interactions, and synergy of lessons. An instrument was developed based on models of other survey instruments (Cantu, 2015) (Appendix A). Content validity experts were recruited, and the instrument was refined as a self-reflective tool. As a self-reflective instrument teachers can use reflective practice to further intentional …

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Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar Jan 2022

Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar

Honors Undergraduate Theses

Hybridization of two or more DNA or RNA strands is well documented for the process taking place with all strands free in solution or when one strand is immobilized on a substrate. This study contributes to the investigation of the hybridization process when two single DNA strands (ssDNA) are in close proximity. We took advantage of an X sensor in which hybridization of four DNA strands enables the formation of a DNA four-way junction (crossover or X) structure. We immobilized multiple layers of crossover structures to study its hybridization being triggered by short ssDNA coming from solution and further investigate …

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Instanton Counting, Matrix Models, And Characters, Spencer Tamagni Jan 2022

Instanton Counting, Matrix Models, And Characters, Spencer Tamagni

Honors Undergraduate Theses

In this thesis we study symmetries of quantum field theory visible only at the non-perturbative level, which arise from large deformations of the integration contour in the path integral. We exposit the recently-developed theory of qq-characters that organizes such symmetries in the case of N = 2 supersymmetric gauge theories in four dimensions. We sketch the physical origin of such observables from intersecting branes in string theory, and the mathematical origin as certain
equivariant integrals over Nakajima quiver varieties. We explain some of the main applications, including the derivation of Seiberg-Witten geometry for quiver gauge theories and the relations to …

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