Physical Sciences and Mathematics Commons^™

The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology., Lori E. Porter

College of Arts & Sciences Senior Honors Theses

The large-scale structure (LSS) of the Universe is comprised of galaxy filaments, tendrils, and voids. The majority of the Universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside voids are void galaxies and expected to be some of the most isolated objects in the Universe. However, their standard morphology remains poorly studied. This study, using the Galaxy and Mass Assembly (GAMA) data and Galaxy Zoo survey, aims to remedy this. For completeness purposes, we use void galaxies identified by Alpaslan et al. (2014) with stellar masses (M*) of 10 …

Repytah: An Open-Source Python Package For Building Aligned Hierarchies For Sequential Data, Chenhui Jia, Lizette Carpenter, Thu Tran, Amanda Y. Liu, Sasha Yeutseyva, Mariun Tapal, Yingke Wang, Zoie Kexin Zhou, Jordan Moody, Denise Nava, Eleanor Donaher, Lillian Yusha Jiang, Ben Bruncati, Katherine M. Kinnaird

Computer Science: Faculty Publications

We introduce repytah, a Python package that constructs the aligned hierarchies representation that contains all possible structure-based hierarchical decompositions for a finite length piece of sequential data aligned on a common time axis. In particular, this representation–introduced by Kinnaird (2016) with music-based data (like musical recordings or scores) as the primary motivation–is intended for sequential data where repetitions have particular meaning (such as a verse, chorus, motif, or theme). Although the original motivation for the aligned hierarchies representation was finding structure for music-based data streams, there is nothing inherent in the construction of these representations that limits repytah to only …

Reverse Mathematics Of Ramsey's Theorem, Nikolay Maslov

Electronic Theses, Projects, and Dissertations

Reverse mathematics aims to determine which set theoretic axioms are necessary to prove the theorems outside of the set theory. Since the 1970’s, there has been an interest in applying reverse mathematics to study combinatorial principles like Ramsey’s theorem to analyze its strength and relation to other theorems. Ramsey’s theorem for pairs states that for any infinite complete graph with a finite coloring on edges, there is an infinite subset of nodes all of whose edges share one color. In this thesis, we introduce the fundamental terminology and techniques for reverse mathematics, and demonstrate their use in proving Kőnig's lemma …

Distance Correlation Based Feature Selection In Random Forest, Jose Munoz-Lopez

Electronic Theses, Projects, and Dissertations

The Pearson correlation coefficient is a commonly used measure of correlation, but it has limitations as it only measures the linear relationship between two numerical variables. In 2007, Szekely et al. introduced the distance correlation, which measures all types of dependencies between random vectors X and Y in arbitrary dimensions, not just the linear ones. In this thesis, we propose a filter method that utilizes distance correlation as a criterion for feature selection in Random Forest regression. We conduct extensive simulation studies to evaluate its performance compared to existing methods under various data settings, in terms of the prediction mean …

Experimental Methodologies In Assessing Ceramic Shrinkage In Residual Fingerprints For Archaeological Application, Luke Aaron Burnor

Electronic Theses, Projects, and Dissertations

This research evaluates the extent of ceramic shrinkage using a natural clay source that was locally available and known to be used by native populations in the American Southwest. The experiment took into account variables of temper mixture and firing temperature to assess the extent and potential need for shrinkage calibration in archaeological biometric research (specifically fingerprints). An experimental design was employed to test shrinkage rates while accounting for natural temper materials found frequently in the archaeological record including sand, grog, and quartz. The experiment evaluated whether shrinkage rates may have skewed data collected in previous studies regarding sex and …

Relative Reactivity Of Six Amino Acids With Sodium Hypochlorite Measured By Gas Chromatography/ Mass Spectrometry And Methyl Chloroformate Derivatization., Josephine Wangui Gitau

Electronic Theses, Projects, and Dissertations

There are 20 common amino acids that act as building blocks for proteins and each one of them differ from each other due to their chemical structure of the R group. During the process of chlorination of water and wastewaters, amino acids present have been implicated as precursors of disinfection by-products. For the analysis of amino acids Gas Chromatography/Mass Spectrometry (GC/MS) is widely used. In this research six amino acids (glycine, valine, leucine, isoleucine, methionine, and phenylalanine) were derivatized with Methyl Chloroformate and analyzed using Gas Chromatography/Mass Spectrometry without heating. The main aim of this study was to observe the …

A Study Of Various Data Sizes Using Machine Learning, Sochaeta Koeum

Electronic Theses, Projects, and Dissertations

Social media is a great domain for news consumption; however, it is referred to as a double-edged sword. While it is user-friendly and low-cost, social media is the reason why fake news can spread rapidly, which is detrimental to society, businesses, and many consumers. Therefore, fake news detection is an emerging field. However, some challenges have restricted other researchers from developing a universal machine learning model that is fast, efficient, and reliable to stop the proliferation because of the lack of resources available, such as large-sized datasets. The goal of this culminating experience project is to explore how varying datasets …

Jackknife Empirical Likelihood Tests For Equality Of Generalized Lorenz Curves, Anton Butenko

Electronic Theses, Projects, and Dissertations

A Lorenz curve is a graphical representation of the distribution of income or wealth within a population. The generalized Lorenz curve can be created by scaling the values on the vertical axis of a Lorenz curve by the average output of the distribution. In this thesis, we propose two nonparametric methods for testing the equality of two generalized Lorenz curves. Both methods are based on empirical likelihood and utilize a U -statistic. We derive the limiting distribution of the likelihood ratio, which is shown to follow a chi-squared distribution with one degree of freedom. We conduct simulations to compare the …

Development Of Nonorthogonal Wavefunction Theories And Application To Multistate Reaction Processes., Emily Kempfer

Electronic Theses and Dissertations

Many prominent areas of technological development rely on exploiting the photochemical response of molecules. An application of particular interest is the control of molecular switches through a combination of different external stimuli. However, despite significant advances in theoretical approaches and numerous cases of successful application of theory, simulating photochemical reactions remains a computational challenge. Theoretical methods for describing excited states can be broadly divided into single-reference response methods and multireference methods. Single reference methods provide reliable semiquantitative results for single excitations. However, these methods cannot describe double-excited states, systems with strongly correlated ground states, or regions of degeneracy on the …

First Principles Study Of 2d Polar Heterostructures., Safia Abdullah R Alharbi

Electronic Theses and Dissertations

Recently, two-dimensional (2D) heterostructures have attracted extensive attention in nanomaterials science. They have been successfully fabricated and applied to nanotechnology in many fields, such as nanoelectronics, solar cells, sensors, energy stores, quantum information, etc. The most common heterostructures are 2D-lateral heterostructure (LH) and 2D-vertical heterostructure (VH) where each of them exhibits unique features depending on the direction of assembly, i.e., along in-plane or out-of-plane direction. Beyond the van der Waals-VH which possess of van der Waals (vdW) interaction, there are other types of heterostructures made of 2D polar materials that possess different types of chemical bonding nature, e.g., chemical bonds …

A Framework For Identifying Malware Threat Distribution On The Dark Web, Shelby Caldwell

<strong> Theses and Dissertations </strong>

The Dark Web is an ever-growing phenomenon that has not been deeply explored. It is no secret that in recent years, malware has become a powerful threat to technology users. The Dark Web is known for supporting anonymity and secure connections for private interactions. Over the years, it has become a rich environment for displaying trends, details, and indicators of emerging malware threats. Through the application of data science and open-source intelligence techniques, trends in malware distribution can be studied. In this research, we create a framework for helping identify malware threat distribution patterns. We examine this type of Dark …

A Case Study In Bivariate Spline Spaces, Ryann Lee Firestine

<strong> Theses and Dissertations </strong>

Loosely speaking, splines are piece-wise polynomial functions which are continuously differentiable of order r. The individual polynomial segments are degree less than or equal to d. Splines are typically associated with approximation theory, computer-aided graphic design, and partial differential equations. Due to the wide variety of applications, mathematicians became interested in better understanding the behavior of the vector spaces containing splines in various setting and values r and d. In particular, many focused on formulating the dimension of these vector spaces. In the 1980s, commutative algebra was first applied to the study of spline spaces. In our work, we use …

Risk Assessment Framework For Evaluation Of Cybersecurity Threats And Vulnerabilities In Medical Devices, Maureen S. Van Devender

<strong> Theses and Dissertations </strong>

Medical devices are vulnerable to cybersecurity exploitation and, while they can provide improvements to clinical care, they can put healthcare organizations and their patients at risk of adverse impacts. Evidence has shown that the proliferation of devices on medical networks present cybersecurity challenges for healthcare organizations due to their lack of built-in cybersecurity controls and the inability for organizations to implement security controls on them. The negative impacts of cybersecurity exploitation in healthcare can include the loss of patient confidentiality, risk to patient safety, negative financial consequences for the organization, and loss of business reputation. Assessing the risk of vulnerabilities …

Magnetic Properties Of Polycrystalline Spinel Oxides From Solid State Reaction, Camden Olds

Honors Theses

Spinel crystal materials of nickel, cobalt, and iron oxides have seen abundant research for their strong conductivity, ferromagnetic and ferroelectric properties, and their catalytic uses. These can be synthesized by a number of means. This project explores the use of the solid state synthesis method, which benefits from simplicity, of this family of materials, looking for interesting phase shift lines in the triangle between of varying compositions of these three metals.

Nickel cobaltite and other related spinels were synthesized from two different solid state approaches and characterized using XRD and SQUID magnetometry. The range 0.5-0.6 of molar ratios of nickel …

A Generalized Family Of Exponentiated Composite Distributions With Applications To Insurance And Survival Data, Bowen Liu

UNLV Theses, Dissertations, Professional Papers, and Capstones

The concept of composite distributions was proposed in the early 2000s as a good parametric solution to model the data with heavy tails. Since the concept was proposed, it has been widely used in different areas, such as modeling insurance claim size data, predicting the risk measures in insurance data analysis, fitting survival time data, and modeling precipitation data. While a lot of the composite distributions demonstrated great performances in real applications, many commonly used composite distributions such as the inverse gamma-Pareto (IGP) or exponential-Pareto (EP), did not demonstrate great performances when fitting to several particular data sets. In order …

Field Observations And Stable Isotope Analysis Of Alunite At The Sulphur Bank Mercury Mine, Clear Lake, California, David Edward Muller

Open Access Theses & Dissertations

The Sulphur Bank mercury mine is a historic mine located in Lake County, California, first exploited in the 1860s. Underground mining of mercury took place from 1873 to 1906 and open-pit mining of mercury was done from 1927 to 1957. The U.S. Environmental Protection Agency listed the Sulphur Bank mine and the adjacent Clear Lake as a Superfund site in 1990 due to mercury contamination at the mine site and in the sediment and food web of Clear Lake. Previous studies have described the vein material mineralogy and wall-rock alteration at Sulphur Bank as well as the composition of water …

Enhancing Basic Geology Skills With Artificial Intelligence: An Exploration Of Automated Reasoning In Field Geology, Perry Ivan Quinto Houser

Open Access Theses & Dissertations

This thesis explores the use of Artificial Intelligence, specifically semantics, ontologies, and reasoner techniques, to improve field geology mapping. The thesis focuses on two use cases: 1) identifying a geologic formation based on observed characteristics; and 2) predicting the geologic formation that might be expected next based upon known stratigraphic sequence. The results show that the ontology was able to correctly identify the geologic formation for the majority of rock descriptions, with higher search results for descriptions that provided more detail. Similarly, the units expected next were correctly given and if incorrect, would provide a flag to the field geologist …

Fault Influence On Castle Mesa Fracture Node Pattern, Kaitlin Steinauer

Theses/Capstones/Creative Projects

Fracture nodes are useful in determining the connectivity of a fracture pattern which is important when considering hydrogeological and mechanical behavior of a rock. Four node types are used to describe the pattern, including isolated (I), perpendicular abutting (T), low-angle abutting (Y), and cross-cutting (X). Faults can affect a fracture pattern by creating a highly fractured zone in their vicinity. I investigate the Moab Tongue Member of the Entrada Formation at Castle Mesa in Moab, Utah to determine a) how the percentage of different node types changes with distance from the fault, b) any difference in node type proportions between …

Artificial: A Study On The Use Of Artificial Intelligence In Art, Hayden Ernst

Theses/Capstones/Creative Projects

In the past three to five years there have been significant improvements made in AI due to improvements in computing capacity, the collection and use of big data, and an increase in public interest and funding for research. Programs such as ChatGPT, DALL•E, and Midjourney have also gained tremendous popularity in a relatively short amount of time. This led me to this project in which I aimed to gain a deeper understanding of these art generator AI and where they fit into art as a whole. My goal was to give recommendations to museums and exhibits in Omaha on what …

The Intersection Of Urban Heat Islands And The Cdc Social Vulnerability Index In Two Border Cities, Ileana Morales

Open Access Theses & Dissertations

No abstract provided.

The Effects Of Prior Calculus Classes On Success In Organic Chemistry, Tori Williamson

Theses/Capstones/Creative Projects

Within University of Nebraska – Omaha (UNO) chemistry-based degree programs, organic chemistry along with at least two semesters of calculus are required courses. There is, however, no requirement for the order in which these courses should be taken. This is mainly due to the notion that for chemistry courses, organic chemistry is detached from the typical quantitative concepts studied in other chemistry-based courses. This is untrue, however, as many organic chemistry concepts rely on three-dimensional spatial visualizations and manipulations. Spatial awareness skills are strengthened within higher-level calculus classes. A survey was administered to organic chemistry students enrolled in 2022-2023. The …

The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford

Theses/Capstones/Creative Projects

This study assesses chemical weathering trends as they relate to glacial retreat. The chemical environment of surfaces exposed to the atmosphere differs significantly from beneath a glacier. As a glacier melts, changes to the biogeochemical processes generate environmental gradients. This study analyzed chemical weathering signals at different distances from a glacial front by comparing the elemental composition of leachate derived from sediments in southeastern Greenland. Samples from proglacial, nonglacial, and moraine locations were weathered in a laboratory setting, and ion chromatography was used to determine the elemental composition of the products. Divergent trends in leachate composition were observed as distance …

Constraining The Sources Of Ultra-High-Energy Cosmic Rays Across And Above The Ankle With The Spectrum And Composition Data Measured At The Pierre Auger Observatory, A. Abdul Halim, P. Abreu, M. Aglietta, I. Allekotte, K. Almeida Cheminant, A. Almela, B. Fick, D. Nitz, I. Norwood, A. Puyleart, Et. Al

Michigan Tech Publications

In this work we present the interpretation of the energy spectrum and mass composition data as measured by the Pierre Auger Collaboration above 6 × 1017 eV. We use an astrophysical model with two extragalactic source populations to model the hardening of the cosmic-ray flux at around 5 × 1018 eV (the so-called "ankle"feature) as a transition between these two components. We find our data to be well reproduced if sources above the ankle emit a mixed composition with a hard spectrum and a low rigidity cutoff. The component below the ankle is required to have a very soft spectrum …

Path Integral Monte Carlo For Entanglement In Bosonic Lattices At T = 0, Emanuel Casiano-Diaz

Doctoral Dissertations

Path-Integral Monte Carlo Worm Algorithm is one of many Quantum Monte Carlo (QMC) methods that serve as powerful tools for the simulation of quantum many-body systems. Developed in the late 90’s, this algorithm has been used with great success to study a wide array of physical models where exact calculation of observables is not possible due to the exponential size of the Hilbert space. One type of systems that have eluded PIMC-WA implementation are lattice models at zero temperature, which are of relevance in experimental settings, such as in optical lattices of ultra-cold atoms. In this thesis, we develop a …

Interdisciplinary And Innovative: A Nursing And Computer Science Collaboration To Create A Barcode Medication Administration System, Jodi Lisbeth Berndt, Peter Ohmann, Imad Rahal, Lindsey Hoeschen, Andrew Rothstein

Nursing Faculty Publications

Preventing medication errors remains a priority in nursing education. The implementation of Barcode Medication Administration (BCMA) systems is one strategy that has been used to reduce medication errors. Practice using BCMA in simulated settings may enhance the transfer of these skills to the clinical practice setting. However, the purchase of BCMA educational products available for nursing students can be cost prohibitive for many nursing programs. To overcome the barrier of cost, an interdisciplinary and innovative collaborative approach was used to create a fully functional low-cost BCMA system.

An Application Risk Assessment Of Werner Enterprises, Nathan Andres

Theses/Capstones/Creative Projects

Risk assessments provide a systematic approach to identifying potential risks that could negatively impact an organization’s operations, financial performance, and reputation. Using a risk assessment, companies can evaluate potential risks and vulnerabilities, prioritize them based on their potential impact, and develop strategies to manage and address these risks effectively.

Werner Enterprises Inc. is a nationally known trucking company headquartered in Omaha, Nebraska. Our cybersecurity capstone project motivation was to partner with Werner to produce an assessment of known application risks in a functional way that can be repeated for all of Werner’s applications. To achieve this, we created a risk …

Predicting The Pebcak: A Quantitative Analysis Of How Cybersecurity Education, Literacy, And Awareness Affect Individual Preparedness., Annie Goodman

Theses/Capstones/Creative Projects

This essay explores the relationship between individuals' cybersecurity education, literacy, awareness, and preparedness. While cybersecurity is often associated with complex hacking scenarios, the majority of data breaches and cyber-attacks result from individuals inadvertently falling prey to phishing emails and malware. The lack of standardized education and training in cybersecurity, coupled with the rapid expansion of technology diversity, raises concerns about individuals' cybersecurity preparedness. As individuals are the first line of defense and the weakest link in cybersecurity, understanding the influence of education, literacy, and awareness on their adherence to best practices is crucial. This work aims to survey a diverse …

Creating The Optimal Wedding Seating Chart, Madison Lane

Theses/Capstones/Creative Projects

The purpose of this project is to develop an effective seating arrangement for a wedding reception that enhances the comfort of guests. The ultimate aim is to create a harmonious and enjoyable atmosphere for all attendees. To achieve this, an integer program was designed to optimize the seating arrangement for the author’s upcoming wedding on May 27th, 2023. To ensure accuracy and feasibility, actual feedback was gathered from the guests to evaluate their compatibility and preferences. The proposed seating chart optimization not only addresses the placement of guests but also determines the number of tables required for the reception. The …

Let’S Make Patterns!: Symmetric Rubik’S Cube Permutations, Danny Anderson

Theses/Capstones/Creative Projects

Rubik’s cubes are well-known for having several different patterns, or permutations, that can be made from them. Meanwhile, cubes generally display a wide variety of symmetries. Naturally, these ideas can be combined to form a notion of "symmetric Rubik's cube patterns." The goal of this paper is to find an algorithm that can produce all of the permutations that display symmetries.

Elucidating Unique Sources And Persistent Hydrologic Pathways Of Chloride To Perennial Freshwater Streams: Root River Analog In A Cold-Weather Environment, Leah Elizabeth Dechant

Theses and Dissertations

Chloride in freshwater streams is increasing in concentration, persisting throughout the year, and contributing to the salinization of water resources. The primary source and pathway of chloride in cold-weather environments are thought to be road salt and runoff. However, mounting evidence displays that other sources and pathways of chloride play an important role yet studies to elucidate them at a high resolution, both temporally and spatially, and across diverse land use are lacking. In this study, chloride was quantified continuously for an urban and rural stream year-round in a watershed thought to be heavily impacted by road salt. Bivariate mixing …