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Emulsion Characterization Study For Improved Bilgewater Treatment And Management, Daniela Diaz Hernandez Jan 2020

Emulsion Characterization Study For Improved Bilgewater Treatment And Management, Daniela Diaz Hernandez

Electronic Theses and Dissertations, 2020-

The need for proper management of bilgewater to meet discharge regulations (e.g., 15 ppm oil) has revealed the necessity to expand the current understanding of bilgewater emulsions. This study proposed to evaluate emulsion stability under various environmental conditions and to identify governing parameters for emulsion formation. The stabilizing properties of eight-commercial cleaners and two-neat surfactants were evaluated. In situ characterization techniques were used for monitoring emulsion stability. Additionally, a needle-type pH microsensor and fluorescence spectroscopy were used for analyzing mass transfer at the oil-water interface. Water quality of extracted bilgewater showed to highly vary between vessels (e.g., conductivity: 1.74 -- …


Tensor Network States: Optimizations And Applications In Quantum Many-Body Physics And Machine Learning, Justin Reyes Jan 2020

Tensor Network States: Optimizations And Applications In Quantum Many-Body Physics And Machine Learning, Justin Reyes

Electronic Theses and Dissertations, 2020-

Tensor network states are ubiquitous in the investigation of quantum many-body (QMB) physics. Their advantage over other state representations is evident from their reduction in the computational complexity required to obtain various quantities of interest, namely observables. Additionally, they provide a natural platform for investigating entanglement properties within a system. In this dissertation, we develop various novel algorithms and optimizations to tensor networks for the investigation of QMB systems, including classical and quantum circuits. Specifically, we study optimizations for the two-dimensional Ising model in a transverse field, we create an algorithm for the $k$-SAT problem, and we study the entanglement …


Tunable Few- To Many-Cycle Source For High-Order Harmonic Generation And Time-Resolved Spectroscopy, John Beetar Jan 2020

Tunable Few- To Many-Cycle Source For High-Order Harmonic Generation And Time-Resolved Spectroscopy, John Beetar

Electronic Theses and Dissertations, 2020-

The temporal confinement of laser light pulses to durations approaching the optical period, and the subsequent conversion of these pulses into extreme ultraviolet and x-ray wavelengths through the process of high-order harmonic generation (HHG), has enabled measurement and control of ultrafast processes spanning picosecond to attosecond timescales. Typically achieved by nonlinear compression of multi-cycle pulses in gas-filled hollow-core fibers, compression to single-and even sub-cycle durations is now becoming routine due to the availability of state-of-the-art Ti:sapphire laser amplifiers outputting millijoule level pulses with pulse durations below ten cycles. Even so, reliance on mJ-level Ti:sapphire lasers has in most cases limited …


Total Synthesis Of Natural Products From Oxidative Dearomatization, Nameer Ezzat Jan 2020

Total Synthesis Of Natural Products From Oxidative Dearomatization, Nameer Ezzat

Electronic Theses and Dissertations, 2020-

The goal of our research is to prepare natural products and related core structures through oxidative dearomatization. The development of a stereoselective iron (III)-mediated intramolecular cascade dearomatization of phenol allowed access to various spirocyclohexadienones and tropons in one step using potassium ferricyanide via single electron transfer (SET). Using this oxidative dearomatization reaction, the thesis focuses on three main parts. The first part is the synthetic efforts toward total synthesis of Harringtonolide. The second part focused on the synthesis of spiro[4.5]decane, a core structure in multiple natural products. The spiro compounds were prepared from ortho hydroxyphenyl nitroalkanes using SET reaction with …


Theoretical Analysis Of The Conduction Properties Of Self Assembled Molecular Tunnel Junctions, Cameron Nickle Jan 2020

Theoretical Analysis Of The Conduction Properties Of Self Assembled Molecular Tunnel Junctions, Cameron Nickle

Electronic Theses and Dissertations, 2020-

As the size scale of electrical devices approach the atomic scale. Moore's law is predicted to be over for semiconductor devices. Studies into the replacement of semiconductor technology with organic devices was first predicted by Avriam and Ratner[1] in 1974. Since then significant research into molecular based organic devices has been conducted. The work presented in this dissertation explores the theoretical frameworks used to model transport through molecular junctions. We present studies which seek to garner a better understanding of the charge transport through molecular junctions and how the conduction properties can be optimized. We show that a single atom …


The Dollar General: Continuous Custom Gesture Recognition Techniques At Everyday Low Prices, Eugene Taranta Jan 2020

The Dollar General: Continuous Custom Gesture Recognition Techniques At Everyday Low Prices, Eugene Taranta

Electronic Theses and Dissertations, 2020-

Humans use gestures to emphasize ideas and disseminate information. Their importance is apparent in how we continuously augment social interactions with motion—gesticulating in harmony with nearly every utterance to ensure observers understand that which we wish to communicate, and their relevance has not escaped the HCI community's attention. For almost as long as computers have been able to sample human motion at the user interface boundary, software systems have been made to understand gestures as command metaphors. Customization, in particular, has great potential to improve user experience, whereby users map specific gestures to specific software functions. However, custom gesture recognition …


Algorithms And Applications Of Novel Capsule Networks, Rodney Lalonde Jan 2020

Algorithms And Applications Of Novel Capsule Networks, Rodney Lalonde

Electronic Theses and Dissertations, 2020-

Convolutional neural networks, despite their profound impact in countless domains, suffer from significant shortcomings. Linearly-combined scalar feature representations and max pooling operations lead to spatial ambiguities and a lack of robustness to pose variations. Capsule networks can potentially alleviate these issues by storing and routing the pose information of extracted features through their architectures, seeking agreement between the lower-level predictions of higher-level poses at each layer. In this dissertation, we make several key contributions to advance the algorithms of capsule networks in segmentation and classification applications. We create the first ever capsule-based segmentation network in the literature, SegCaps, by introducing …


Atomic Scale Processes And Electronic Band Structure Engineering In Thin Layered Materials, Brandon Blue Jan 2020

Atomic Scale Processes And Electronic Band Structure Engineering In Thin Layered Materials, Brandon Blue

Electronic Theses and Dissertations, 2020-

In this work, a variety of layered materials are considered for their potential technologic applications and the role of structure on the physical properties of the material system as a whole. Transition metal dichalcogenides form the core of the work discussed here, with additional results from an iron pnictide-based superconductor and for a biologically-sourced proton conductor. Here, a commercial scanning tunneling microscope (STM) with liquid cryogenic cooling provides information about both the atomic-scale structure of the surface and the local electronic density of states (LDOS) as a function of position. The interplay of superconducting and charge-density wave states is discussed …


Efficient String Algorithms With Applications In Bioinformatics, Sahar Hooshmand Jan 2020

Efficient String Algorithms With Applications In Bioinformatics, Sahar Hooshmand

Electronic Theses and Dissertations, 2020-

The work presented in this dissertation deals with establishing efficient methods for solving some algorithmic problems, which have applications to Bioinformatics. After a short introduction in Chapter 1, an algorithm for genome mappability problem is presented in Chapter 2. Genome mappability is a measure for the approximate repeat structure of the genome with respect to substrings of specific length and a tolerance to define the number of mismatches. The similarity between reads is measured by using the Hamming distance function. Genome mappability is computed for each position in the string and has several applications in designing high-throughput short-read sequencing experiments. …


The Effects Of Gesture Presentation In Video Games, Jack Oakley Jan 2020

The Effects Of Gesture Presentation In Video Games, Jack Oakley

Electronic Theses and Dissertations, 2020-

As everyday and commonplace technology continues to move toward touch devices and virtual reality devices, more and more video games are using gestures as forms of gameplay. While there is much research focused on gestures as user interface navigation methods, we wanted to look into how gestures affect gameplay when used as a gameplay mechanic. In particular, we set out to determine how different ways of presenting gestures might affect the game's difficulty and flow. We designed two versions of a zombie game where the zombies are killed by drawing gestures. The first version of the game is a touchscreen-based …


Action Recognition In Still Images: Confluence Of Multilinear Methods And Deep Learning, Marjaneh Safaei Jan 2020

Action Recognition In Still Images: Confluence Of Multilinear Methods And Deep Learning, Marjaneh Safaei

Electronic Theses and Dissertations, 2020-

Motion is a missing information in an image, however, it is a valuable cue for action recognition. Thus, lack of motion information in a single image makes action recognition for still images inherently a very challenging problem in computer vision. In this dissertation, we show that both spatial and temporal patterns provide crucial information for recognizing human actions. Therefore, action recognition depends not only on the spatially-salient pixels, but also on the temporal patterns of those pixels. To address the challenge caused by the absence of temporal information in a single image, we introduce five effective action classification methodologies along …


Reconstruction Of Bacterial Strain Genomes From Shotgun Metagenomic Reads, Xin Li Jan 2020

Reconstruction Of Bacterial Strain Genomes From Shotgun Metagenomic Reads, Xin Li

Electronic Theses and Dissertations, 2020-

It is necessary to study bacterial strains in environmental samples. The environmental samples are mixed DNA samples collected from the ocean, soil, lake, human body sites, etc. In a natural environment, they provide us new insights into the diversity of our earth. As for bacterial strains on or inside human bodies, to select the proper treatment for diseases caused by bacterial strains, it is critical to identify the corresponding strains and reconstruct their genomes. However, it is a challenge to do so with the DNA from a large number of unknown microbial species mixed together in an environmental sample. The …


Computational Methods For Discovery And Analysis Of Rna Structural Motifs, Shahidul Islam Jan 2020

Computational Methods For Discovery And Analysis Of Rna Structural Motifs, Shahidul Islam

Electronic Theses and Dissertations, 2020-

Understanding the 3D structural properties of RNAs will play a critical role in identifying their functional characteristics and designing new RNAs for RNA-based therapeutics and nanotechnology. In an attempt to achieve a better insight into RNAs, biochemical experiments have been conducted to produce data with positional details of atoms in RNA structures. This data has created opportunities for applying computational analysis to solve various biological problems. In this dissertation, we have addressed annotation issues of base-pairing interactions in the low-resolution structure data and presented new methods to analyze RNA structural motifs. Annotating base-pairing interactions is one of the critical steps …


The Physical Properties Of Asteroids, Leos Pohl Jan 2020

The Physical Properties Of Asteroids, Leos Pohl

Electronic Theses and Dissertations, 2020-

The Small Bodies of the Solar System are leftover material from the formation of planets. Compared with planetary bodies, they have undergone little transformation. Embedded in their physical properties, they provide clues to the conditions and processes that took place since the condensation of the Solar Nebula. Furthermore, asteroids are sources of raw materials that are becoming more costly to obtain from the interior of the Earth. The possibilities of extracting those materials has become a topic of significant interest. In this dissertation, I explore several properties of asteroid material: strength of asteroids, their shielding properties against high energetic particles …


Algorithms For Inferring Multiple Microbial Networks, Sahar Tavakoli Jan 2020

Algorithms For Inferring Multiple Microbial Networks, Sahar Tavakoli

Electronic Theses and Dissertations, 2020-

The interactions among the constituent members of a microbial community play a major role in determining the overall behavior of the community and the abundance levels of its members. These interactions can be modeled using a network whose nodes represent microbial taxa and edges represent pairwise interactions. A microbial network is a weighted graph that is constructed from a sample-taxa count matrix and can be used to model co-occurrences and/or interactions of the constituent members of a microbial community. The nodes in this graph represent microbial taxa and the edges represent pairwise associations amongst these taxa. A microbial network is …


Seaweed As A Carrier For Microplastics, Stephanie M. Rodriguez Jan 2020

Seaweed As A Carrier For Microplastics, Stephanie M. Rodriguez

Honors Undergraduate Theses

Analysis of seaweed as a vector for microplastics is an integral part of understanding the formation and deposition of micro-sized plastic waste in seawater. The project itself originated due to the influx of seaweed (and mismanaged plastic waste) residing on the shores of St. Kitts and Nevis and the constant deposition of plastic pollution intertwined within the seaweed. The natural occurrence of the two together lead to the consideration of fragmented plastics remaining on the seaweed. The objective of this research is to stain, identify, and quantify the concentration of microplastics sourced from both store-bought and environmental seaweed samples. A …


Algebraic And Combinatorial Approaches For Counting Cycles Arising In Population Biology, Brian Chau Jan 2020

Algebraic And Combinatorial Approaches For Counting Cycles Arising In Population Biology, Brian Chau

Honors Undergraduate Theses

Within population biology, models are often analyzed for the net reproduction number or other generalized target reproduction numbers, which describe the growth or decline of the population based on specific mechanisms. This is useful in determining the strength and efficiency of control measures for inhibiting or enhancing population growth. The literature contains many algebraic and combinatorial approaches for deriving the net reproduction number and generalized target reproduction numbers from digraphs and associated matrices. Finding, categorizing, and counting the permutations of disjoint cycles, or cycles unions is a requirement of the Cycle Union approach by Lewis et al. (2019). These cycles …


Development Of An Environmental Disposition Scale: A Guide For Fostering Sustainable Behavior, Jady Chen Jan 2020

Development Of An Environmental Disposition Scale: A Guide For Fostering Sustainable Behavior, Jady Chen

Honors Undergraduate Theses

Promoting sustainable behavior or environmentally responsible behavior poses challenges because there is no overarching solution for behavior changes. Both surveys and interventions are context specific, meaning behaviors do not necessarily influence other behaviors and the same values, norms, and beliefs do not necessarily translate to the same level of sustainable behavior. Because there are regional differences in ideologies in the United States, a country level approach to encourage sustainable behavior would not be as effective as having interventions that directly correlate with the motivations that encourage environmentally responsible behavior. A survey will be conducted with University of Central Florida undergraduate …


Detection Of A Peptide Hormone - Somatostatin - Label-Free Split-Aptameric Probes, Charles A. Dowis Jan 2020

Detection Of A Peptide Hormone - Somatostatin - Label-Free Split-Aptameric Probes, Charles A. Dowis

Honors Undergraduate Theses

Peptide hormones are important biomolecules that transduce downstream effects such as cell proliferation, regulation, and gene expression. Their levels have been upregulated in various disorders such as cancer, yet detection methods are lacking. We designed two split aptamer-based assays for the detection of a peptide hormone – Somatostatin (SST) – with different signal readouts: fluorescent readout based on light-up aptamers and the colorimetric readout of ABTS peroxidation from a G-quadruplex. We used an already selected split-aptamer –SSTA5–for SST for our designs and we had expected the developed detection systems to exhibit detection and quantification capabilities that would hopefully allow their …


A Model Experiment To Investigate The Possibility Of Glyphosate Contamination In St. Kitts And Nevis, Winston Fu Jan 2020

A Model Experiment To Investigate The Possibility Of Glyphosate Contamination In St. Kitts And Nevis, Winston Fu

Honors Undergraduate Theses

Glyphosate is a broad-spectrum herbicide that is used globally to combat the spread of weeds among crops. Not all countries around the world have been using the herbicide. For example, island countries such as Dominica and St. Kitts and Nevis do not use the herbicide on their crops. However, St. Kitts and Nevis imports food and other agricultural products from around the world, leading to the hypothesis that glyphosate is contaminating the soil through those imported products. The aim of this research project was to determine if glyphosate is present in the island country of St. Kitts and Nevis. A …


Musical Cryptography Using Long Short-Term Memory Networks, Curtis Helsel Jan 2020

Musical Cryptography Using Long Short-Term Memory Networks, Curtis Helsel

Honors Undergraduate Theses

Musical cryptography is a technique in which plain text messages are enciphered into a musical composition. Recently, a surge of music composition by means of machine learning have produced natural-sounding music that can be deemed as composed by humans. The combination of machine-generated music and enciphering a message into the composition is a logical step in musical cryptography. Outlined in this thesis is a method that incorporates the use of a specific type of recurrent neural network, Long Short-Term Memory, and a variant of the substitution cipher to form of symmetric-key cryptography system. Exploration was also completed to determine how …


Predicting Structures Of 2d Materials Enabled By Machine Learning, Sonali Joshi Jan 2020

Predicting Structures Of 2d Materials Enabled By Machine Learning, Sonali Joshi

Honors Undergraduate Theses

Prediction of stable structures of two-dimensional (2D) materials that have not been experimentally realized is an important pre-requisite step for the development of these materials for various technological uses without the extensive trial-error experiments. Traditional methods such as density functional theory (DFT) can be used to find the energies of structures computationally, however, calculating the energies of the total number of structures possible would be daunting timewise as well. We propose using machine learning methods to reduce the search time for 2D materials’ geometric structures. Our case study for this process consists of hexagonal graphene-like boron–carbon–nitrogen (h-BCN). Our …


Equivariance And Invariance For Robust Unsupervised And Semi-Supervised Learning, Liheng Zhang Jan 2020

Equivariance And Invariance For Robust Unsupervised And Semi-Supervised Learning, Liheng Zhang

Electronic Theses and Dissertations, 2020-

Although there is a great success of applying deep learning on a wide variety of tasks, it heavily relies on a large amount of labeled training data, which could be hard to obtain in many real scenarios. To address this problem, unsupervised and semi-supervised learning emerge to take advantage of the plenty of cheap unlabeled data to improve the model generalization. In this dissertation, we claim that equivariant and invariance are two critical criteria to approach robust unsupervised and semi-supervised learning. The idea is as follows: the features of a robust model ought to be sufficiently informative and equivariant to …


Nonlinear Optical Mechanisms In Semiconductors And Enhanced Nonlinearities At Epsilon-Near-Zero, Sepehr Ahmadzadeh Benis Jan 2020

Nonlinear Optical Mechanisms In Semiconductors And Enhanced Nonlinearities At Epsilon-Near-Zero, Sepehr Ahmadzadeh Benis

Electronic Theses and Dissertations, 2020-

Light does not interact with itself in linear optical materials. Such interactions occur only in non-linear optical (NLO) materials and typically require high intensity optical beams to be signifi-cant. The ever-increasing role of NLO, where intense light may change the properties of the me-dium, has created a pressing demand to invent materials for achieving more efficient light-light and light-matter interaction due to their potential capacity to augment and possibly replace cur-rent technologies with more efficient devices. There are numerous applications of NLO devices in fundamental science, technology, health, and defense such as all-optical computation and sig-nal processing, ultrashort laser technology, …


Attosecond Transient Absorption Spectroscopy In The Water Window, Andrew Chew Jan 2020

Attosecond Transient Absorption Spectroscopy In The Water Window, Andrew Chew

Electronic Theses and Dissertations, 2020-

The push to study the atomic and molecular dynamics at ever smaller time scales has been the main driving force for developing laser systems with ever shorter pulse durations. Thus far, picosecond lasers and femtosecond lasers have been used with great success in femtochemistry to study molecular dynamics such as molecular rotation and vibration, which all occur in the tens to hundreds of femtosecond. To study electron dynamics however, which are on the order of attoseconds, one needs attosecond laser sources to be able to have the time resolution required to probe ultrafast electron dynamics such as AC Stark shifts, …


Theoretical Studies Of Collisions Involving Three Bodies And Electron-Molecule Collisions Relevant To Astrophysical And Atmospheric Conditions, Chi Hong Yuen Jan 2020

Theoretical Studies Of Collisions Involving Three Bodies And Electron-Molecule Collisions Relevant To Astrophysical And Atmospheric Conditions, Chi Hong Yuen

Electronic Theses and Dissertations, 2020-

Accurate rate coefficients of atomic and molecular processes allow us to probe the conditions in space and understand the history of the Universe. Although experimental rate coefficients are the most desirable, availability of accurate rate coefficients of some processes depends on rigorous theoretical studies. In this dissertation, theoretical tools for collisions involving three bodies are discussed and applied to three different reactions. Rate coefficient of the reactive scattering of H2 + D- is computed using the ABC program. The present results are about ten times smaller than the experimental upper limit, suggesting that a further improvement of the sensitivity of …


3d Localization Of Defects In Facility Inspections, Nicholas Califano Jan 2020

3d Localization Of Defects In Facility Inspections, Nicholas Califano

Electronic Theses and Dissertations, 2020-

Wind tunnels are crucial facilities that support the aerospace industry. However, these facilities are large, complex, and pose unique maintenance and inspection requirements. Manual inspections to identify defects such as cracks, missing fasteners, leaks, and foreign objects are important but labor and schedule intensive. The goal of this thesis is to utilize small Unmanned Aircraft Systems with onboard cameras and computer vision-based analysis to automate the inspection of the interior and exterior of NASA's critical wind tunnel facilities. Missing fasteners are detected as the defect class, and existing fasteners are detected to provide potential future missing fastener sites for preventative …


Discovery Of New Topological Quantum Materials By Photoemission, Md Mofazzel Hosen Jan 2020

Discovery Of New Topological Quantum Materials By Photoemission, Md Mofazzel Hosen

Electronic Theses and Dissertations, 2020-

A topological insulator (TI) is a novel electronic state of quantum matter characterize by a bulk insulating bandgap and spin-polarized metallic surface states. Recently, the idea of topology protected surface states extended to semimetallic/metallic systems such as Dirac and Weyl semimetals. Unlike topological insulators where only surface states are interesting and topologically protected, Dirac and Weyl semimetals feature unusual bands in both on the surface and bulk. Dirac semimetals show photon-like linear band dispersion and exhibit a variety of exotic properties that include surface Fermi arc, large magnetoresistance, and high carrier mobility, etc. Recently, a new type of topological phase …


Novel Fibers And Components For Space Division Multiplexing Technologies, Juan Carlos Alvarado Zacarias Jan 2020

Novel Fibers And Components For Space Division Multiplexing Technologies, Juan Carlos Alvarado Zacarias

Electronic Theses and Dissertations, 2020-

Passive devices and amplifiers for space division multiplexing are key components for future deployment of this technology and for the development of new applications exploring the spatial diversity of light. Some important devices include photonic lantern (PL) mode multiplexers supporting several modes, fan-in/fan-out (FIFO) devices for multicore fibers (MCFs), and multimode amplifiers capable of amplifying several modes with low differential modal gain penalty. All these components are required to overcome the capacity limit of single mode fiber (SMF) communication systems, driven by the growing data capacity demand. In this dissertation I propose and develop different passive components and amplifiers for …


Iterative Optical Diffraction Tomography For Reconstruction Of Multiply-Scattering Objects, Shengli Fan Jan 2020

Iterative Optical Diffraction Tomography For Reconstruction Of Multiply-Scattering Objects, Shengli Fan

Electronic Theses and Dissertations, 2020-

As a label-free, non-destructive, high-resolution, and quantitative imaging technique, optical diffraction tomography (ODT) has been widely used to image biological samples and microstructures, such as cells, tissues, and optical fibers. The refractive-index (RI) distribution of an object is reconstructed from multi-view measurements of diffracted fields emerging from the object. Typical ODT setups include the object rotating configuration (ORC) and the illumination scanning configuration (ISC). One major limitation of ODT is that it is only applicable to weakly-scattering objects. In this dissertation, novel methods have been developed to overcome the reconstruction difficulty caused by multiple scattering, so as to extend ODT …