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Linux Malware Obfuscation, Brian Roden May 2023

Linux Malware Obfuscation, Brian Roden

Computer Science and Computer Engineering Undergraduate Honors Theses

Many forms of malicious software use techniques and tools that make it harder for their functionality to be parsed, both by antivirus software and reverse-engineering methods. Historically, the vast majority of malware has been written for the Windows operating system due to its large user base. As such, most efforts made for malware detection and analysis have been performed on that platform. However, in recent years, we have seen an increase in malware targeting servers running Linux and other Unix-like operating systems resulting in more emphasis of malware research on these platforms. In this work, several obfuscation techniques for Linux …


Design Of A Sigma-Delta Adc In 65nm Cmos Process, Michael Lee Thompson Iii May 2023

Design Of A Sigma-Delta Adc In 65nm Cmos Process, Michael Lee Thompson Iii

Electrical Engineering Undergraduate Honors Theses

Analog and digital signals both play a vital role in electrical engineering and the technology of today. As the role of electrical and computer engineers becomes more deeply involved in the development of new technology, an understanding of how these signals are utilized, and what they represent, is a necessity. Due to the inherent limitations involved with analog signals, there is a need for these signals to be accurately and efficiently converted to digital signals for processing. The job of the analog-to-digital converter, or ADC, is to receive this analog input signal (voltage or current) and create a digital representation …


Geochemical Analysis And Numerical Modeling Of Central And East Tennessee Mississippi Valley-Type Ore Districts: Constraints On Ore Genesis, Jackson Price Copeland May 2023

Geochemical Analysis And Numerical Modeling Of Central And East Tennessee Mississippi Valley-Type Ore Districts: Constraints On Ore Genesis, Jackson Price Copeland

Geosciences Undergraduate Honors Theses

A simple two-way stochastic mixing model is presented for analysis of the lead (Pb) isotope compositions of the North American Mississippi Valley-Type (MVT) districts of East Tennessee, Central Tennessee, and Central Kentucky. Four distinct mixing scenarios were run to critically evaluate the stochastic model and examine different hypotheses regarding the genesis of Central Tennessee and Central Kentucky MVT deposits. Additionally, Pb isotope analysis was conducted on sphalerite samples from the Central and East Tennessee MVT districts. Model and sampling results suggest that Central Tennessee and Central Kentucky ores likely formed by mixing of three fluids. In contrast to conclusions from …


Reverse Engineering Post-Quantum Cryptography Schemes To Find Rowhammer Exploits, Sam Lefforge May 2023

Reverse Engineering Post-Quantum Cryptography Schemes To Find Rowhammer Exploits, Sam Lefforge

Computer Science and Computer Engineering Undergraduate Honors Theses

Post-quantum cryptography is a necessary countermeasure to protect against attacks from quantum computer. However, the post-quantum cryptography schemes are potentially vulnerable to side channel attacks. One such method of attacking involves creating bit-flips in victim memory through a process called Rowhammer. These attacks can vary in nature, but can involve rowhammering bits to raise the encryption scheme's decryption failure rate, or modifying the scheme's random seed. With a high enough decryption failure rate, it becomes feasible to generate sufficient information about the secret key to perform a key recovery attack. This thesis proposed two attacks on proposed post-quantum cryptography algorithms, …


Realtime In-Network Cyberattack Detection In Power Grid Systems Using A Programmable Network, Luke Waind May 2023

Realtime In-Network Cyberattack Detection In Power Grid Systems Using A Programmable Network, Luke Waind

Computer Science and Computer Engineering Undergraduate Honors Theses

Power grid communication networks are important systems to detect intrusions from an attacker due to them being necessary to maintain critical infrastructure. This thesis applies recent advancements in P4 technology to detect cyberattacks in SCADA systems. In previous work, a list has been compiled of potential attacks that exploit one of the most common protocols in SCADA systems, DNP3. Solutions for detecting these attacks can be categorized by the broad methods that they use. The two methods that are focused on are single-packet inspection and multiple-packet inspection. For each of these, a specific attack is chosen and a detection algorithm …


Critical Infrastructure Workforce Development Pods For Teaching Cybersecurity Using Netlab+, Gideon Sutterfield May 2023

Critical Infrastructure Workforce Development Pods For Teaching Cybersecurity Using Netlab+, Gideon Sutterfield

Computer Science and Computer Engineering Undergraduate Honors Theses

As digital automation for Industrial Control Systems has grown, so has its vulnerability to cyberattacks. The world of industry has responded effectively to this, but the world of academia is still lagging as its emphasis is still almost entirely on information technology. Considering this, we created a workforce development pod that serves as a hands-on learning module for teaching students key cybersecurity ideas surrounding operational technology using the NETLAB+ platform. A pod serves as the virtual environment where the learning exercise takes place. This project’s implementation involved the creation of a segmented network within the pod where a student starts …


Gradient Estimates And The Fundamental Solution For Higher-Order Elliptic Systems With Lower-Order Terms, Ariel E. Barton, Michael J. Duffy Jr. May 2023

Gradient Estimates And The Fundamental Solution For Higher-Order Elliptic Systems With Lower-Order Terms, Ariel E. Barton, Michael J. Duffy Jr.

Mathematical Sciences Faculty Publications and Presentations

We establish the Caccioppoli inequality, a reverse Hölder inequality in the spirit of the classic estimate of Meyers, and construct the fundamental solution for linear elliptic differential equations of order 2m with certain lower order terms.


Quantifying The Effect Of Socio-Economic Predictors And The Built Environment On Mental Health Events In Little Rock, Ar, Alfieri Ek, Grant Drawve, Samantha Robinson, Jyotishka Datta May 2023

Quantifying The Effect Of Socio-Economic Predictors And The Built Environment On Mental Health Events In Little Rock, Ar, Alfieri Ek, Grant Drawve, Samantha Robinson, Jyotishka Datta

Sociology and Criminology Faculty Publications and Presentations

Law enforcement agencies continue to grow in the use of spatial analysis to assist in identifying patterns of outcomes. Despite the critical nature of proper resource allocation for mental health incidents, there has been little progress in statistical modeling of the geo-spatial nature of mental health events in Little Rock, Arkansas. In this article, we provide insights into the spatial nature of mental health data from Little Rock, Arkansas between 2015 and 2018, under a supervised spatial modeling framework. We provide evidence of spatial clustering and identify the important features influencing such heterogeneity via a spatially informed hierarchy of generalized …


Excitation Power Dependence Of Blinking In Copper-Indium-Sulfide Quantum Dots, Nicholas Chambers May 2023

Excitation Power Dependence Of Blinking In Copper-Indium-Sulfide Quantum Dots, Nicholas Chambers

Physics Undergraduate Honors Theses

Under continuous excitation, quantum dots exhibit random transitions between fluorescent ON states and non-fluorescent OFF states --- a phenomenon known as blinking. A physical description of the mechanism responsible for blinking that applies broadly to many types of quantum dots remains under debate. We study the blinking behavior of the non-toxic CuInS2 quantum dot, a system that has seen little investigation at the single-particle level. In particular, the optical properties of CuInS2 quantum are often improved by adding ZnS to the nanoparticles, but this addition leads to complex structural-optical property relationships that are even less understood. To probe the relationship …


Culture In Computing: The Importance Of Developing Gender-Inclusive Software, Creighton France May 2023

Culture In Computing: The Importance Of Developing Gender-Inclusive Software, Creighton France

Computer Science and Computer Engineering Undergraduate Honors Theses

The field of computing as we know it today exists because of the contributions of numerous female mathematicians, computer scientists, and programmers. While working with hardware was viewed as “a man’s job” during the mid-20th century, computing and programming was viewed as a noble and high-paying field for women to occupy. However, as time has progressed, the U.S. has seen a decrease in the number of women pursuing computer science. The idea that computing is a masculine discipline is common in the U.S. today for reasons such as male-centered marketing of electronics and gadgets, an inaccurate representation of what it …


Analysis On High Mass X-Ray Binary Spectral Shape Dependence On Luminosity For Ngc3310, Izabela Pavel May 2023

Analysis On High Mass X-Ray Binary Spectral Shape Dependence On Luminosity For Ngc3310, Izabela Pavel

Physics Undergraduate Honors Theses

In most normal galaxies, the most X-ray luminous sources are high-mass X-ray binaries (HMXBs), which are binary star systems that contain compact objects (black holes or neutron stars) accreting from massive (> 8M⊙) companion stars. These HMXBs are thought to have been important sources of ionizing emission within star-forming galaxies that may have contributed to the heating of the intergalatic medium (gas over large cosmic scales) in the early Universe. When studying how HMXBs contribute to interstellar medium feedback, a single spectral shape of an absorbed power-law is typically assumed to be universal. The goal of this thesis is to …


Automating The Determination Of Tight-Binding Representations For Two-Dimensional Ferroelectrics, Joseph Roll May 2023

Automating The Determination Of Tight-Binding Representations For Two-Dimensional Ferroelectrics, Joseph Roll

Physics Undergraduate Honors Theses

Two-dimensional (atomically thin) materials have been greatly explored in the last two decades since the exfoliation of graphene in 2004. Since then, many exotic material properties have been shown for these systems; these new properties often arise from certain crystal symmetries or lack thereof. One of interest is ferroelectricity in which a noncentrosymmetric crystal structure can lead to a switchable intrinsic electric dipole in our material. This can then lead to second-harmonic generation in which two photons enter a material at a given frequency and one photon exits the material at double the original frequency. The study presented here makes …


Biochar As A Lake Management Option For Harmful Algal Blooms: Lab Experiments And Bioassays, Brittany Mc Intyre May 2023

Biochar As A Lake Management Option For Harmful Algal Blooms: Lab Experiments And Bioassays, Brittany Mc Intyre

Graduate Theses and Dissertations

Harmful Algal Blooms (HABs) are an increasing global concern for water management due to their increased frequency, distribution, and toxin production. In freshwaters the growth of cyanobacteria (commonly known as blue-green algae), due to anthropogenic nutrient enrichment is the primary driver of HABS; these are often referred to as cyanoHABs. The management of cyanoHABs should be focused on in the watershed through best management and conservation practices or the physical, chemical and biomanipulation of the lake or reservoir that is experiencing these blooms. In this study, we examine the use of biochar as an option for the management or treatment …


Improving Tribological Properties Of Polydopamine/Polytetrafluoroethylene Coatings Through Incorporating Core-Shell Nanoparticles And Laser Surface Texturing, Firuze Soltani-Kordshuli May 2023

Improving Tribological Properties Of Polydopamine/Polytetrafluoroethylene Coatings Through Incorporating Core-Shell Nanoparticles And Laser Surface Texturing, Firuze Soltani-Kordshuli

Graduate Theses and Dissertations

Polytetrafluoroethylene (PTFE) is a widely used polymer that has unique properties such as chemical and temperature resistance, corrosion resistance, low maintenance cost, and a very low coefficient of friction (COF). These distinctive properties have made PTFE a promising candidate for industrial applications where surfaces are in relative motion. PTFE can be utilized as a thin film solid lubricant to significantly reduce the friction between moving surfaces. However, PTFE coatings have low cohesion and poor adhesion to the substrate resulting in its low wear resistance. This fact limits the application of PTFE coatings in load-bearing situations. To address these limitations, an …


Personal Equation, Nicholas Hobbs May 2023

Personal Equation, Nicholas Hobbs

Graduate Theses and Dissertations

The body of this paper is a formatted version of text which exists natively on the web and is accessible at www.personalequation.art. Its non-linear narrative is meant to accompany and mirror, not describe, the artwork in the exhibition. The following two paragraphs are copied from the exhibition statement accompanying Personal Equation, which is on view in the Reading Room at the Fayetteville Public Library from April 3 to June 30, 2023: A personal equation is one that attempts to account for the inevitable role of subjectivity in scientific observations. The term was coined by astronomers in the 18th century who, …


Evaluation Of Hydrogeochemical Characteristics Of San Joaquin, Tulare, And Mojave Aquifers, Southern California, Maedeh Hassanvand May 2023

Evaluation Of Hydrogeochemical Characteristics Of San Joaquin, Tulare, And Mojave Aquifers, Southern California, Maedeh Hassanvand

Graduate Theses and Dissertations

Before making attempts to enhance and manage the quality of water, a thorough understanding of these processes is necessary since the chemical quality of groundwater is impacted by a number of linked processes. This would be more important in arid and semiarid regions like the southern part of California where more rely on groundwater for agriculture and drinking water uses than the other states. As a result, fundamental knowledge of the governing processes of groundwater chemistry is required for effective water resource management. Thus, this study is primarily concerned with three aspects in Mojave, Tulare, and San Joaquin aquifers: The …


Modeling And Control Strategies For A Two-Wheel Balancing Mobile Robot, John Alan Moritz May 2023

Modeling And Control Strategies For A Two-Wheel Balancing Mobile Robot, John Alan Moritz

Graduate Theses and Dissertations

The problem of balancing and autonomously navigating a two-wheel mobile robot is an increasingly active area of research, due to its potential applications in last-mile delivery, pedestrian transportation, warehouse automation, parts supply, agriculture, surveillance, and monitoring. This thesis investigates the design and control of a two-wheel balancing mobile robot using three different control strategies: Proportional Integral Derivative (PID) controllers, Sliding Mode Control, and Deep Q-Learning methodology. The mobile robot is modeled using a dynamic and kinematic model, and its motion is simulated in a custom MATLAB/Simulink environment. The first part of the thesis focuses on developing a dynamic and kinematic …


Geophysical Assessment Of Internal Erosion Damage At The Crawford County Levee, Samuel Ross Hokett May 2023

Geophysical Assessment Of Internal Erosion Damage At The Crawford County Levee, Samuel Ross Hokett

Graduate Theses and Dissertations

Levee failures during flooding events can result in catastrophic loss of life and property. Soil erosion during high water events is a primary cause of levee failures. Accordingly, this research focuses on the geophysical assessment of internal erosion damage in levees. This thesis presents a case study utilizing Capacitively Coupled Resistivity (CCR), Direct Current Electrical Resistivity Tomography (DC ERT), and Multichannel Analysis of Surface Waves (MASW) to assess internal erosion damage at the Crawford County Levee System in Van Buren, AR, that occurred during the 2019 Arkansas River flood. Geophysical surveys acquired included longitudinal CCR, DC ERT, and MASW lines …


Framing How We Think About Curves, Megan Sattler May 2023

Framing How We Think About Curves, Megan Sattler

Mathematical Sciences Undergraduate Honors Theses

A frame defines a basis at a point in R^n, and we can frame a curve by placing one at every point along it. This thesis investigates adapted framed curves in R^2 and R^3 in which they are used to provide information about how a curve twists and turns. We derive differential information from the frames that describe how they change and consequently how the curve changes. We also deduce special properties of each framing and discuss how the differential information suffices to describe the shape of curves.


Effects Of Land Use On Soil Microbial Communities In Tropical Montane Forests Of Malaysian Borneo, Yang Kai Tang May 2023

Effects Of Land Use On Soil Microbial Communities In Tropical Montane Forests Of Malaysian Borneo, Yang Kai Tang

Graduate Theses and Dissertations

Land use, such as logging and forest conversion to agriculture, can modify soil physicochemical and biological properties, and affect soil health. To understand how land use change can impact soil properties and canopy structure, we used a land use gradient in Malaysian Borneo consisting of six sites, including old growth forests, mixed forests, and agriculture fields. Specifically, we aimed to answer the following questions: (1) How do soil physicochemical properties vary across land use types? (2) Does bacterial diversity and composition vary across different land use types? (3) Does fungal diversity and composition vary across different land use types? We …


Insights Into Star Formation And Agn Activity In Protocluster Environments From Morphological Studies And Sed Fitting, Erik B. Monson May 2023

Insights Into Star Formation And Agn Activity In Protocluster Environments From Morphological Studies And Sed Fitting, Erik B. Monson

Graduate Theses and Dissertations

In this dissertation I present work done from 2018-2023 to investigate the growth of galaxies and supermassive black holes (SMBH) in high redshift overdensities (protoclusters) by studying the star-forming galaxy and active galactic nucleus (AGN) population in the SSA22 protocluster. I examined possible environmental sources of the enhanced star formation and AGN activity in the z = 3.09 SSA22 protocluster using Hubble WFC3 ∼ 1.6 μm observations of the SSA22 field, including new observations centered on eight X-ray selected protocluster AGN. To investigate the role of mergers in the observed AGN and star formation enhancement, quantitative and visual morphological classifications …


Early Childhood Educational Toys Through An Architectural Perspective, Anindhitha Sudhakaran May 2023

Early Childhood Educational Toys Through An Architectural Perspective, Anindhitha Sudhakaran

Architecture Undergraduate Honors Theses

This capstone explores the overlaps between architectural training and early childhood education, and how architectural design can inform the design process of creating educational toys for young children. Through an analysis of pedagogies used throughout history in early childhood education and my own personal experiences of architecture school, an understanding of how an architectural perspective can influence activities for three- to five-year-olds is developed. Precedent studies of open-ended educational toys designed by educators and designers introduced the design thinking mindset necessary to create an effectively enriching toy. The next phase of this project involves designing an educational toy for the …


Designing For Mass Customization Housing Through Generative Design, Tania Salgueiro May 2023

Designing For Mass Customization Housing Through Generative Design, Tania Salgueiro

Architecture Undergraduate Honors Theses

This research proposal aims to investigate computational design strategies for sustainable, affordable, and more equitable housing. The study will focus on the use of generative design tools, such as parametric modeling, rule-based modeling, and optimization, to aid architects and designers in creating custom housing complexes for single families in small and medium urban lots. The goal is to develop a computational method that considers sustainability, affordability, and long-term usage parameters to create housing designs that meet the desired spatial qualities. The research question asks how generative design tools can support designers in approaching affordable housing given the increasing demand for …


Chicken Keypoint Estimation, Rohit Kala May 2023

Chicken Keypoint Estimation, Rohit Kala

Computer Science and Computer Engineering Undergraduate Honors Theses

Poultry is an important food source across the world. To facilitate the growth of the global population, we must also improve methods to oversee poultry with new and emerging technologies to improve the efficiency of poultry farms as well as the welfare of the birds. The technology we explore is Deep Learning methods and Computer Vision to help automate chicken monitoring using technologies such as Mask R-CNN to detect the posture of the chicken from an RGB camera. We use Meta Research's Detectron 2 to implement the Mask R-CNN model to train on our dataset created on videos of chickens …


Medication Errors In Pediatric Care And Preventative Solutions, Tyler Tidwell May 2023

Medication Errors In Pediatric Care And Preventative Solutions, Tyler Tidwell

Political Science Undergraduate Honors Theses

The research presented extensively examines previous reports covering pediatric medication errors (PMEs). Utilizing specific studies into the frequency and types of medication errors along with public surveys and policy discussion, the data and suggestions here provide commentary on the scope of PMEs, suggested institutional reform, and most importantly, legislative recommended action necessary to stymie the tide of PMEs. A significant portion of the research contained fixates on the literature review to provide ample familiarity with the background and scope of PMEs, but the subsequent sections will discuss their implication. After providing details on the magnitude of the issue, regulatory and …


Facebook In County 4-H Extension Programs In Arkansas: Is It Effective For Communication?, Haley Padgett May 2023

Facebook In County 4-H Extension Programs In Arkansas: Is It Effective For Communication?, Haley Padgett

Graduate Theses and Dissertations

As social media rises in popularity, agents with 4-H responsibilities have the opportunity to implement social media platforms in their communication outreach. The purpose of this study was to identify how agents with 4-H responsibilities in Arkansas use Facebook for communication purposes and their perceptions of its effectiveness. This information helps provide understanding of the effects of Facebook on county 4-H programs in Arkansas and assists agents in determining how to implement or better utilize Facebook in their county programs. The study had three research objectives: 1) describe the usage of Facebook by agents in Arkansas with at least a …


Subterraneans: A Regional Earth Dwelling For Comfort And Beauty, Isaak Benchoff May 2023

Subterraneans: A Regional Earth Dwelling For Comfort And Beauty, Isaak Benchoff

Architecture Undergraduate Honors Theses

Subterraneans is a study of an affordable, self-sufficient, sustainable, and dignified housing prototype for the region of Northwest Arkansas. It is a design process investigation based on the ideas of turning a local, sustainable material into affordable homes that can be built within a community of people sharing land and resources. The homes would utilize as many natural materials as possible to minimize the impact on the Earth and the cost to the owners.

Research looked at many different vernacular building precedents as well as the work done by contemporary design firms in the area of economical, low-impact, and passively …


Photon Correlation Measurements And Second Harmonic Generation Using Pulsed Lasers, Apoorva Bisht May 2023

Photon Correlation Measurements And Second Harmonic Generation Using Pulsed Lasers, Apoorva Bisht

Physics Undergraduate Honors Theses

Correlation measurements are one of the fundamental ways to understand the photon statistics/distribution for a source of light. It is also an important method to confirm single photon sources by confirming the anitbunching nature. This project developed a correlation measurement system, utilized field programmable gate arrays, and non-linear crystals for processes like second harmonic generation and down conversion.


Consumer Valuation And Preferences For Sustainably Produced Rice In Ghana, Vera Adabrah-Danquah May 2023

Consumer Valuation And Preferences For Sustainably Produced Rice In Ghana, Vera Adabrah-Danquah

Graduate Theses and Dissertations

Sustainable agricultural production is a systematic concept that integrates environmental health, economic profitability, and social/economic equity goals. Improving the sustainability of food production is of utmost importance to the human race, given the growing population and the increased depletion of natural resources. Improving sustainability is particularly important for rice, a global food staple with a significant environmental footprint. Rice accounts for 10% of global methane emissions. The Sustainable Rice Platform (SRP) standard is the first globally recognized certified sustainable production standard for rice. This study focuses on consumers' preferences for sustainable rice in Ghana, including consumers’ perceptions of different SRP's …


Characterization Of Public Opinion On Severity Of Mental Illness And Hiv Based On Individual Traits Using Hierarchical Multi-Category Probit Models, Md Moinul Ahsan May 2023

Characterization Of Public Opinion On Severity Of Mental Illness And Hiv Based On Individual Traits Using Hierarchical Multi-Category Probit Models, Md Moinul Ahsan

Graduate Theses and Dissertations

In this thesis, we focus on modeling categorical response variables from public opinion datasets. A hierarchical probit model was used to analyze these different variables. Particularly for multinomial data, we tried different covariate settings to see the model’s performance. For that purpose, we tried two different estimation techniques. The first algorithm uses identified parameters by fixing the first diagonal element of the covariance matrix at 1. The second algorithm uses one unidentifiable parameter and subsequently identifies the parameters by fixing the trace of the covariance matrix. The results from the simulation study confirm that the trace-restricted algorithm performs better with …