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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Evaluation Of Emerging Screening Technologies For The On-Site Detection And Identification Of Methamphetamine And Its Precursors In Simulated Clandestine Lab Operations, Alexis Nicole Wilcox Jan 2023

Evaluation Of Emerging Screening Technologies For The On-Site Detection And Identification Of Methamphetamine And Its Precursors In Simulated Clandestine Lab Operations, Alexis Nicole Wilcox

Graduate Theses, Dissertations, and Problem Reports (ETD)

Stimulant drugs comprise one of the top drug categories abused in the United States. Due to its accessibility, low price, and manufacturing simplicity, methamphetamine is frequently placed within the top 10 seized drugs in the country. As of March 2023, methamphetamine is the most seized controlled substance in the United States, with 34,291 kg. In 2022, the United States seized over 79,000 kg of methamphetamine. One reason for the proliferation of methamphetamine is related to the production itself, which does not require large warehouses but can be manufactured in houses using relatively accessible materials and small containers. When a clandestine …


The Influence Of Spirituality On Caregiver Burden And Quality Of Life In Older Adult Informal Caregivers, Stephanie Marie Young Jan 2023

The Influence Of Spirituality On Caregiver Burden And Quality Of Life In Older Adult Informal Caregivers, Stephanie Marie Young

Graduate Theses, Dissertations, and Problem Reports (ETD)

Background: Caregiver burden reduces quality of life (QOL) and is associated with poorer health outcomes. Older adults may be more susceptible to caregiver burden due to advancing age and declining health. Spirituality has been shown to reduce caregiver burden and improve QOL.

Purpose: The purpose of this study was to evaluate the direct or indirect influence of spirituality on caregiver burden and caregiver QOL in older adult caregivers. The specific aims were 1) to determine the prevalence of caregiver burden in a nationally representative sample of older adult informal caregivers of other adults and 2) to investigate the relationships among …


Forecasting And Optimizing Sensitivity To Low-Frequency Gravitational Waves, Andrew Ryan Kaiser Jan 2023

Forecasting And Optimizing Sensitivity To Low-Frequency Gravitational Waves, Andrew Ryan Kaiser

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pulsars are among the most exotic objects in our Universe. These rapidly
spinning, high magnetic field neutron stars can be used for a wide range of
scientific studies: from the makeup of their own extremely dense and poorly
understood interior to using their extremely regular signals to detect gravita-
tional waves (GWs). Pulsar timing continues to expand to broader communi-
ties, with larger and more sensitive radio telescopes planned and partnerships
between pulsar timing arrays (PTAs) that span the entire globe. A realm of
new physics with the detection of a background hum of gravitational waves
from black holes merging …


Framework For Data Acquisition And Fusion Of Camera And Radar For Autonomous Vehicle Systems, Clay Edward Vincent Jan 2023

Framework For Data Acquisition And Fusion Of Camera And Radar For Autonomous Vehicle Systems, Clay Edward Vincent

Graduate Theses, Dissertations, and Problem Reports (ETD)

The primary contribution is the development of the data collection testing methodology for autonomous driving systems of a hybrid electric passenger vehicle. As automotive manufacturers begin to develop adaptive cruise control technology in vehicles, progress is being made toward the development of fully-autonomous vehicles. Adaptive cruise control capability is classified into five levels defined by the Society of Automotive Engineering. Some vehicles under development have attained higher levels of autonomy, but the focus of most commercial development is Level 2 autonomy. As the level of autonomy increases, the sensor technology becomes more advanced with a sensor suite which includes radar, …


The Influence Of Instrumental Sources Of Variance On Mass Spectral Comparison Algorithms, Isabel Cristina Galvez Valencia Jan 2023

The Influence Of Instrumental Sources Of Variance On Mass Spectral Comparison Algorithms, Isabel Cristina Galvez Valencia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Current search algorithms for the identification of substances based only on their electron ionization mass spectra provide the correct compound as their top result approximately 80% of the time. One contributing factor to the ~20% deviation in the first-hit recognition rate is that traditional algorithms work by comparing the unknown spectrum to an ‘ideal’ or consensus spectrum of each reference compound. The inclusion of replicate reference spectra in a database has been shown to improve the probability of ranking the correct identity in the number one position, but the variance in ion abundances caused by different conditions or different instruments …


Synthesis Of Quasi-Freestanding Graphene Films Using Radical Species Formed In Cold Plasmas, Michael A. Mathews Jr. Jan 2023

Synthesis Of Quasi-Freestanding Graphene Films Using Radical Species Formed In Cold Plasmas, Michael A. Mathews Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

For over a decade, the Stinespring laboratory has investigated scalable, plasma assisted synthesis (PAS) methods for the growth of graphene films on silicon carbide (SiC). These typically utilized CF4-based inductively coupled plasma (ICP) with reactive ion etching (RIE) to selectively etch silicon from the SiC lattice. This yielded a halogenated carbon-rich surface layer which was then annealed to produce the graphene layers. The thickness of the films was controlled by the plasma parameters, and overall, the process was readily scalable to the diameter of the SiC wafer.

The PAS process reproducibly yielded two- to three-layer thick graphene films …


Exploring Opportunities And Challenges Of Adopting Exoskeletons And Exosuits In Construction: Identifying Facilitators, Barriers, And Potential Solutions To Those Barriers, Dilruba Mahmud Jan 2023

Exploring Opportunities And Challenges Of Adopting Exoskeletons And Exosuits In Construction: Identifying Facilitators, Barriers, And Potential Solutions To Those Barriers, Dilruba Mahmud

Graduate Theses, Dissertations, and Problem Reports (ETD)

Exoskeletons and exosuits (collectively termed as EXOs) have the potential to reduce the risk of work-related musculoskeletal disorders (WMSDs) by protecting workers from exertion and muscle fatigue due to physically demanding, repetitive, and prolonged work in construction workplaces. However, the use of EXOs in construction is in its infancy, and much knowledge for driving acceptance, adoption, and application of this technology is still lacking. This paper aims to identify the potential facilitators and barriers to adopting EXOs in the construction industry, along with potential solutions to those identified barriers to fostering the adoption of EXOs in construction workplaces through a …


Workflow For Integrating Geomechanics, Hydraulic Fracturing, And Reservoir Simulation To Determine Marcellus Shale Horizontal Well Production Potential, Awadh Aljassasi Jan 2023

Workflow For Integrating Geomechanics, Hydraulic Fracturing, And Reservoir Simulation To Determine Marcellus Shale Horizontal Well Production Potential, Awadh Aljassasi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main goal of the study was to accurately predict the production potential of Marcellus shale horizontal well with multistage of hydraulic fractures by incorporating geomechanical factors, gas adsorption, hydraulic fracturing treatment data in the reservoir simulation model. To achieve this goal, core plug measurements, well logs, image logs, hydraulic fracture treatment data, and production data were analyzed, combined, and used to develop a reservoir simulation model. Rocks mechanical properties were estimated from the well logs and then correlated with the core measurement to accurately predict the minimum horizontal stress in the reservoir. Adsorption characteristics, porosity, and permeability were estimated …


Quantifying Variation In High-Quality Footwear Replicate Impressions, Samantha K. Brady Jan 2023

Quantifying Variation In High-Quality Footwear Replicate Impressions, Samantha K. Brady

Graduate Theses, Dissertations, and Problem Reports (ETD)

A footwear impression collected at a crime scene can provide information about the shoe that created it, yielding investigative leads, excluding persons-of-interest, and linking evidence between cases. The analysis of footwear evidence often requires the preparation of test impressions from known exemplar shoes created under controlled laboratory conditions for comparison to questioned impressions. The goal of these comparisons is to evaluate the degree of similarities and differences between the questioned impression and potential sources.

Given that this comparison leads to an assessment of the nature and degree of agreement between questioned and known impressions, it is important to characterize the …


Applications In Macroeconometrics, Corey J.M. Williams Jan 2023

Applications In Macroeconometrics, Corey J.M. Williams

Graduate Theses, Dissertations, and Problem Reports (ETD)

The title of this work, "Applications in Macroeconometrics," reflects the unifying theme of my essays: new, and original research in applied macroeconomics, and applied econometrics. This dissertation consists of three chapters specifically looking at producer price inflation pass-through, technical progress, and moral hazard in United States critical banking markets.

My first chapter seeks to quantify the pass-through (PT) and causal direction of producer to consumer prices. We further disaggregate PPI down to commodity-specific indices to quantify disaggregated PPI PT coefficients. By estimating an augmented Phillips Curve, we find short-run PT of aggregate PPI to be around 7 percent. Using a …


Morphological, Physiological, And Transcriptional Responses Of Populus Trichocarpa To Water Deficit Stress, Kristin Justine Ratliff Jan 2023

Morphological, Physiological, And Transcriptional Responses Of Populus Trichocarpa To Water Deficit Stress, Kristin Justine Ratliff

Graduate Theses, Dissertations, and Problem Reports (ETD)

Under the threat of climate change with continued fossil fuel use, investment in developing renewable energies is increasingly important. One category of renewable energy sources, biofuels, is well suited to industries that require a liquid fuel source. However, producing biofuel feedstocks is challenging from a sustainability perspective, as they require extensive land area and resource input to grow on marginal lands. The identification of strategies that feedstock species use to maintain productivity with limited to no resource inputs could aid in the selection of optimal genotypes or targets of breeding or engineering efforts to maximize productivity in feedstock plantations. Some …


Response Maintenance By Mediated Reinforcement With Forced Alternation Of Reinforcement Opportunities, Kento Yasukawa Jan 2023

Response Maintenance By Mediated Reinforcement With Forced Alternation Of Reinforcement Opportunities, Kento Yasukawa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Three experiments were conducted to investigate the effects of mediated reinforcement –reinforcers delivered to either of two co-actors by the responses of the other co-actor, but independently of the responses of the co-actor receiving the reinforcer– on the maintenance of responding of the co-actors. In each experiment, using a discrete-trials procedure, responding and receiving reinforcers alternated between co-actors. In Experiment 1, the alternation followed each reinforcer. Also investigated in this experiment were the effects of the presence and absence of social stimuli and of the role of reinforcement delays on individual responding. The number of consecutive reinforcer deliveries to either …


Internalized Heterosexism, Shame Proneness, And Disclosure In Clinical Supervision Among Sexual Minority Supervisees, Christian Joseph Carey Jan 2023

Internalized Heterosexism, Shame Proneness, And Disclosure In Clinical Supervision Among Sexual Minority Supervisees, Christian Joseph Carey

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sexual minority supervisees face unique struggles including prejudice, discrimination, and heterosexism, which may impact their psychological well-being and development within the supervisory experience through shame proneness and reduced disclosure. This study aims to explore the challenges facing sexual minority trainees and contribute to the empirical knowledge of multicultural supervision. Thus, this study proposes two mediation models for the hypothesized relationships among internalized heterosexism, shame-related withdrawal, shame-related negative self-evaluation, and disclosure in supervision. A total of 170 supervisees identifying as sexual minorities completed an online survey. The primary analysis included a three-step linear regression and confirmatory analysis for mediation. The results …


Effects Of Combined Ethanol And Nicotine Administration On Delay Discounting In Male And Female Sprague-Dawley Rats, Rebecca Lillian Chalme Jan 2023

Effects Of Combined Ethanol And Nicotine Administration On Delay Discounting In Male And Female Sprague-Dawley Rats, Rebecca Lillian Chalme

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethanol (EtOH) and nicotine (NIC) are among the most commonly used and co-used drugs in the world. Co-use occurs in people who use one or both drugs chronically, but also in people who only consume one or both drugs acutely, often in a “bingeing and chipping” pattern. Given that each drug on its own has previously been shown to affect impulsive choice in delay-discounting procedures, with some indication that drug effects could vary by sex, the purpose of the present experiments was to investigate effects of combined EtOH and NIC at a range of dose combinations on delay discounting in …


Mitigation And Preparedness In Disaster Communication: Examining The Need For Closing The Loop In The Discourse Of Renewal Theory, Abigail Renee Riggs Jan 2023

Mitigation And Preparedness In Disaster Communication: Examining The Need For Closing The Loop In The Discourse Of Renewal Theory, Abigail Renee Riggs

Graduate Theses, Dissertations, and Problem Reports (ETD)

Flooding across rural Appalachia has historically negatively impacted communities, and flood frequency is only expected to increase in the region as global temperatures rise. This indicates a need for effective disaster and crisis communication in flood-prone communities within the region. The discourse of renewal and readiness for renewal theories provide potential avenues for improving crisis and disaster communication. Readiness for renewal in particular focuses on closing the gap between the pre and post-crisis phases. However, readiness for renewal has yet to be applied to disaster communication and has not been studied qualitatively. Additionally, ethical guidelines for communication within renewal have …


Evaluation Of Commission And Omission Errors During Differential Reinforcement Of Other Behavior, Lindsey M. Hronek Jan 2023

Evaluation Of Commission And Omission Errors During Differential Reinforcement Of Other Behavior, Lindsey M. Hronek

Graduate Theses, Dissertations, and Problem Reports (ETD)

Differential reinforcement of other behavior (DRO) is a reinforcement schedule that commonly includes the delivery of a reinforcer following an interval during which a target behavior did not occur and extinction (i.e., the reinforcer is withheld following any instances of the target behavior). Although interventions using DRO schedules can decrease target behavior when implemented as designed, little is known about the efficacy of DRO interventions when they include fidelity errors. A growing field of literature has demonstrated different ways fidelity errors can affect the outcomes of other interventions (e.g., DRA, response cost, and skill acquisition). One study by Foreman et …


Bedrock Channel Geometry: Meter To Micron Scale Controls On Fluvial Incision, Nicholas J. Colaianne Jan 2023

Bedrock Channel Geometry: Meter To Micron Scale Controls On Fluvial Incision, Nicholas J. Colaianne

Graduate Theses, Dissertations, and Problem Reports (ETD)

The relative resistance of various rock types to incisional processes vary widely and the properties governing bedrock erodibility are poorly understood. Lithologic properties influencing erodibility are the culmination of a rock’s depositional, diagenetic, and exhumation processes. Difficulty identifying a convenient physical proxy for erodibility suggests examining evidence of these processes holistically may offer insight into the role of each in setting a rock’s resistance to incisional forces. In this study we use measured channel geometries along a short stretch of the Dry Fork, WV hosting three distinct lithologic settings to infer relative erodibility against measured and observed fluvial, lithologic, and …


Love, Life, And Controversial Topics: A Content Analysis Of The Top Liked Abortion Tiktok Videos Before And After The Overturning Of Roe V. Wade, Jill E. Sturges Jan 2023

Love, Life, And Controversial Topics: A Content Analysis Of The Top Liked Abortion Tiktok Videos Before And After The Overturning Of Roe V. Wade, Jill E. Sturges

Graduate Theses, Dissertations, and Problem Reports (ETD)

TikTok is a trendy social media platform that has attracted billions of monthly users. Anyone can post a short video about their interests, beauty, relationships, travel, and controversial topics if they are 13 or older. Many young adults turn to social media platforms, such as TikTok, to help them make decisions regarding their everyday lives and to discuss controversial topics, such as abortion. The concern with social media content is the misinformation and disinformation that can spread rapidly across the globe with a click of a button. Numerous studies have begun to examine social media platforms for the accuracy of …


Challenges And Solutions For Native Mandarin-Chinese Speakers In Singing German Lieder, Fei Xia Jan 2023

Challenges And Solutions For Native Mandarin-Chinese Speakers In Singing German Lieder, Fei Xia

Graduate Theses, Dissertations, and Problem Reports (ETD)

ABSTRACT Challenges and Solutions for Native Mandarin-Chinese Speakers in Singing German Lieder Fei Xia The purpose of this research is to focus on the challenges faced by Mandarin-Chinese speaking singers singing German Lieder, as well as providing these singers with solutions for overcoming these difficulties. Singing art songs such as French Mélodies and German Lieder can greatly improve singers’ artistic and aesthetic values because of the beauty of the poetry and the language. However, it is very difficult for native Mandarin- Chinese speakers to sing German Lieder. Some of the primary difficulties faced by Mandarin-Chinese-speaking singers are German diction and …


Effects Of Ethanol And Nicotine Co-Administration On Risky Choice In Rats, Erin E. Wylie Jan 2023

Effects Of Ethanol And Nicotine Co-Administration On Risky Choice In Rats, Erin E. Wylie

Graduate Theses, Dissertations, and Problem Reports (ETD)

Individuals often engage in the comorbid use of alcohol (ethanol) and nicotine, leading to further-escalated health consequences than the use of either drug in isolation. Given the poor health outcomes resulting from the combined administration of ethanol and nicotine, some of which may be due to increased risky choice, more basic research is needed to better characterize drug/dose interactions on risky choice. Probability-discounting procedures involve a series of discrete choices between a smaller, certain reinforcer (i.e., a safer choice) and a larger, increasingly uncertain reinforcer (i.e., a riskier choice). Probability-discounting procedures allow for the assessment of …


Evaluating The Effects Of Modifying Mixing And Pelleting Parameters On Feed Quality, Pellet Production Rate, And Broiler Performance, Lucas E. Knarr Jan 2023

Evaluating The Effects Of Modifying Mixing And Pelleting Parameters On Feed Quality, Pellet Production Rate, And Broiler Performance, Lucas E. Knarr

Graduate Theses, Dissertations, and Problem Reports (ETD)

In Chapter 2, an experiment was conducted to evaluate the effect of different mixer types (MTY) and mix times (MTI) on mix uniformity (MU). A 2 (mix time) x 3 (mixer type) factorial was utilized in this experiment to create six treatments, each mixed in three randomized complete blocks. Mix times were designated adequate or inadequate, were based on the manufacturers’ recommendation, and varied based on the mixer utilized. The mixer types utilized included a vertical mixer, horizontal mixer, and transfer mixing system. The transfer mixing system can be described as a batch-to-mix system …


Cue Reactivity In Electronic Cigarette Users With Sign-Tracking Or Goal-Tracking Behaviors, Polina Krom Jan 2023

Cue Reactivity In Electronic Cigarette Users With Sign-Tracking Or Goal-Tracking Behaviors, Polina Krom

Graduate Theses, Dissertations, and Problem Reports (ETD)

Polina Krom

Cue reactivity is an important predictor of addiction course and relapse. However, cue reactivity is only observed after an addiction develops. As such, it is unclear to what degree cue reactivity represents a state stemming from the addiction process versus a trait-like propensity towards developing cue-reward associations. Work in animal models has pointed to important individual differences in trait-like inclination to attribute incentive salience to reward-predictive cues that is associated with addiction-relevant behavioral and neurobiological features. These individual differences manifest as sign-tracking (ST) and goal-tracking (GT) behaviors during Pavlovian conditioning. Little research has attempted to translate ST and …


Footwear Image Quality Classification: Using Subjective Assessments And Objective Image Metrics To Predict Impression Quality, En-Tni Lin Jan 2023

Footwear Image Quality Classification: Using Subjective Assessments And Objective Image Metrics To Predict Impression Quality, En-Tni Lin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Shoeprints deposited during the commission of a crime vary in quality as a function of numerous factors, such as substrates, media, and the specific physical activities carried out by perpetrators. This variability in impression quality impacts the amount of information available from questioned crime scene impressions, and therefore an examiner's confidence in providing opinions of source attribution. In response, this research attempted to characterize footwear impression quality based on image sharpness, contrast, entropy, homogeneity, noise, quantity of information, and complexity, and to integrate these hand-engineered feature descriptions with subjective opinions of impression quality.

The methodology followed a five-pronged approach. First, …


Applications Of Digital Filters In Radio Astronomy, Joseph William Kania Jan 2023

Applications Of Digital Filters In Radio Astronomy, Joseph William Kania

Graduate Theses, Dissertations, and Problem Reports (ETD)

The radio sky spans tens of orders of magnitude in length, density, and time.
In this thesis, using novel filtering techniques and two different telescopes,
we investigate two tracers of cosmic structure: Baryon Acoustic Oscillations
(BAOs) and Fast Radio Bursts (FRBs). BAOs formed as the universe cooled
after the Big Bang. BAOs provide a fiducial length scale of the universe
throughout cosmic time and thus can be used to understand how the universe
is evolving. FRBs are very bright, short timescale, bursts of as-yet unknown
origin which occur uniformly on the sky at a rate of a few thousand per …


Probabilistic Short Term Solar Driver Forecasting With Neural Network Ensembles, Joshua Daniell Jan 2023

Probabilistic Short Term Solar Driver Forecasting With Neural Network Ensembles, Joshua Daniell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Commonly utilized space weather indices and proxies drive predictive models for thermosphere density, directly impacting objects in low-Earth orbit (LEO) by influencing atmospheric drag forces. A set of solar proxies and indices (drivers), F10.7, S10.7, M10.7, and Y10.7, are created from a mixture of ground based radio observations and satellite instrument data. These solar drivers represent heating in various levels of the thermosphere and are used as inputs by the JB2008 empirical thermosphere density model. The United States Air Force (USAF) operational High Accuracy Satellite Drag Model (HASDM) relies on JB2008, and …


“Ingenious Entanglements”: Sheriffs, Capitalism, And Civil Society In America, 1750-1850, Chad R. Holmes Jan 2023

“Ingenious Entanglements”: Sheriffs, Capitalism, And Civil Society In America, 1750-1850, Chad R. Holmes

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sheriffs served as indispensable legal actors who facilitated the expansion of democracy and capitalist transformation, processes that eventually limited their ability to profit from their work and diminished their social status. This dissertation is organized around specific sheriffs and the actions they performed to illustrate how county officers influenced society beyond the execution of court orders. These men—Rhode Island’s Beriah Brown, Pennsylvania’s John Barker, and Massachusetts’s Elisha Porter, Luke Baldwin, and Charles P. Sumner—believed they understood how to balance community demands and state directives in ways that would produce personal profit and greater authority. The work of these officers and …


Abundance-Habitat Relationships And Aquatic-Terrestrial Habitat Selection Patterns For Wood Turtles (Glyptemys Insculpta) In The Upper Midwest, Jena Marie Staggs Jan 2023

Abundance-Habitat Relationships And Aquatic-Terrestrial Habitat Selection Patterns For Wood Turtles (Glyptemys Insculpta) In The Upper Midwest, Jena Marie Staggs

Graduate Theses, Dissertations, and Problem Reports (ETD)

Due to range-wide population declines, wood turtles (Glyptemys insculpta) are under review for federal listing under the United States Endangered Species Act. Understanding how habitat associations and environmental conditions influence population dynamics and spatiotemporal activity patterns is fundamental for designing effective management strategies. Previous work on wood turtle abundance-habitat relationships focused on broad-scale habitat relationships in northeastern North America. However, regional differences in climate, habitat conditions, and land use patterns limit their applicability to much of the wood turtle’s Upper Midwest distribution. Much of our understanding of wood turtle activity patterns is based on radiotelemetry studies, which are biased towards …


Glial Cell-Specific Contribution Of Pkr-Like Er Kinase (Perk) In Neuroinflammation And Behavior, Anirudhya Lahiri Jan 2023

Glial Cell-Specific Contribution Of Pkr-Like Er Kinase (Perk) In Neuroinflammation And Behavior, Anirudhya Lahiri

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neurological disorders such as multiple sclerosis (MS) are a major public health concern in the US, with no available therapeutic cure. Chronic neuroinflammation and aberrant proteostasis in the central nervous system (CNS) are the major hallmarks of neurological diseases. Endoplasmic Reticulum (ER) is a major cellular organelle involved in protein synthesis, folding and maturation of various secretory and transmembrane proteins. Pathophysiological stressors such as trauma and infection result in misfolded protein accumulation in the endoplasmic reticulum (ER) lumen, which results in ER stress. To regain proteostasis (protein homeostasis), cells activate the unfolded protein response (UPR). UPR is an evolutionarily conserved …


Characterizing & Mitigating Interstellar Scattering In Radio Observations Of Pulsars, Jacob E. Turner Jan 2023

Characterizing & Mitigating Interstellar Scattering In Radio Observations Of Pulsars, Jacob E. Turner

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pulsars are rapidly rotating neutron stars that emit concentrated beams of radiation from their magnetic poles. Measuring the arrival of these pulses via pulsar timing is a powerful tool in efforts to detect low frequency gravitational waves (GWs). However, the interstellar medium (ISM) presents a significant source of timing uncertainty that must be mitigated to improve the sensitivity of pulsar timing efforts to these GW signals. By examining the effects of pulsar emission interactions with this medium, we can properly correct for the resulting effects in pulsar timing efforts, as well as study the astronomical unit-to-parsec scale structure and behavior …


Advancing Prosthetic Design Using Neural And Mechanical Dynamics, Kacie E. Hanna Jan 2023

Advancing Prosthetic Design Using Neural And Mechanical Dynamics, Kacie E. Hanna

Graduate Theses, Dissertations, and Problem Reports (ETD)

Limb loss poses a significant challenge to mobility and the performance of daily activities. Currently, nearly half of the amputees using powered prosthetics abandon their device due to inadequate limb coordination and movement control abilities. In the healthy system, passive and neural dynamics facilitate the synchronized activation of muscles necessary for coordinated movement. However, in the amputee, the system is disrupted. The goal of this research is to use neural and mechanical dynamics to inform the design of prosthetic devices in order to restore intuitive control and coordinated limb movement.

The first aim of this research is to investigate neural …