Digital Commons Network^™

A Variable Shape Metastructure Based On Controlled Bistable Structural Elements, Mehmet R. Simsek

Mechanical & Aerospace Engineering Theses & Dissertations

The so-called hybrid position feedback controller is an unstable-then-stable position feedback controller, which is a second-order single-degree-of-freedom system in nature. This hybrid controller takes advantage of the resonant mode of a bistable system about one equilibrium position, destabilizes the system, and dynamically induces snap-through between the two equilibria. In this dissertation, a new multi degree of freedom metastructure concept that utilizes the hybrid position feedback controller is introduced. An arbitrary number of bistable “segments” or “structural elements” are attached to each other in a serial (or parallel) manner to generate a “distributed” bistable structure – also referred to as a …

Study Of Deep Learning Models To Classify Nasa’S Kepler Light Curves, Heena Minnich

Computer Science Theses & Dissertations

The search for exoplanets has been an ongoing effort since the first discoveries of planets beyond our solar system in the 1990s. Finding a potentially habitable planet outside our solar system could provide key insights on life elsewhere in the universe. NASA Missions such as the Kepler, launched in 2009 and completed in 2018, have provided a massive amount of data in this goal by using the transit method to discover repetitive and periodic dips in visible light around a star. The transit method has been used to measure flux, the brightness of a star over time. These flux time …

Examining The Role Of Access To Capital, Social Capital Networks, And Education In Supporting Black Founders And Investors In Technology-Based Entrepreneurship, Akosua Acheamponmaa

Engineering Management & Systems Engineering Theses & Dissertations

In recent years, a report from the Kauffman Index of Startup Activity shows that 540,000 Americans launch businesses each month (Fairlie et al., 2017). However, the number of women-owned and minority-owned businesses in the United States (U.S.) is disproportionately less than the proportion of women and minorities in the U.S. Although women slightly outnumber men in the U.S. (U.S. Census Bureau, 2019), new women-owned businesses represent only 39.4% of all U.S. businesses, while new male-owned businesses represent 60.51% (Fairlie et al., 2017). While Blacks or African Americans comprise approximately 13.4% of the U.S. population (U.S. Census Bureau, 2019), only 9.24% …

A Trustworthy Self-Sovereign Data And Identity Management Framework, Efat Fathalla

Electrical & Computer Engineering Theses & Dissertations

Data is a fundamental building block in the digital world, providing a basis for decision making and growth across numerous applications. In our modern world, we have become accustomed to collecting data on everything, including devices, machines, and people. The increased value of such data has led to aggressive harvesting mechanisms that prioritize data collection, storage, and pervasiveness while often disregarding security, privacy concerns, and compliance with regulations and standards. Such a pervasive attitude towards data has resulted in a loss of control, prompting concerns among individuals and mobilizing the scientific community towards advocating for data self-sovereignty.

Self-Sovereign Identity (SSI) …

A Clinical Problem-Solving Model For Identifying And Addressing Barriers To Learning In Skill-Acquisition Programs, Landon Scott Cowan

Dissertations (1934 -)

Applied Behavior Analysis (ABA) services for learners with autism spectrum disorder (ASD) and other intellectual and developmental disabilities frequently involve teaching a variety of skills, such as those related to communication, daily-living, and safety. There is an extensive literature available demonstrating effective instructional procedures (e.g., discrete-trial teaching, prompt-fading strategies) as well as procedural or environmental modifications that clinicians can apply when teaching these skills; however, minimal literature exists to guide clinicians in applying these procedures when learners encounter a barrier to learning. Thus, it is unclear what systematic methods, if any, clinicians are using to determine efficacious and efficient instructional …

Becoming Hispanic-Serving Institutions (Hsis): Disrupting Institutional Whiteness, Jacqueline Black

Dissertations (1934 -)

Hispanic-Serving Institutions (HSIs) educate disproportionately large percentages of Latinx and other underrepresented minority (URM) postsecondary students. But as most HSIs are also Historically White Colleges, whiteness permeates their campus structures, cultures, and practices. This study bridges gaps in our understanding around how legacies of historical whiteness on campuses that have recently become or are emerging as HSIs affect their efforts to serve Latinx/URM students. The project focuses on the perspectives of those faculty, staff, and administrators most intimately involved in “servingness” work on these campuses: HSI specialists. Employing a critical qualitative approach and guided by Critical Whiteness Studies and Omi …

An Evaluation Of Probabilistic Delay And Denial Training: Durability Against Treatment Relapse, Kendall Mae Kastner

Dissertations (1934 -)

Delay and Denial Teaching is a prevalent prescribed intervention following successful implementation of Functional Communication Training (FCT). Although there is strong empirical evidence in support of delay and denial teaching as an intervention to reach socially acceptable outcomes, there has yet to be systematic assessments of this intervention’s susceptibility to treatment relapse. The goal of this evaluation is to arrange treatment challenges which mimic the conditions that threaten treatment outcomes in the natural environment, specifically transferring treatment to a new environment or treatment integrity omission errors. Researchers replicated recent iterations of delay and denial teaching procedures (Hanley et al., 2014; …

Probing Charge Transport Mechanisms In 2d Semiconductive Metal Organic Framewoks, James Nyakuchena

Dissertations (1934 -)

Metal organic frameworks (MOFs) are a class of highly porous crystalline materials constructed from metal nodes connected by multitopic organic ligands. Due to their unique properties such as large surface area, tunable pore structure, and structural diversity, they have demonstrated potential in a wide array of applications including gas storage and separation, sensing, catalysis, and drug delivery. However, there are only a handful of MOFs reported that have electrical conductivity, which prevents their applications in photoelectronic and photocatalytic applications. This is because hard metals and redox inactive ligands with terminal hard linking bases such as carboxylates are often used in …

Immune Cell And Muscle Bioenergetics In Persons With Multiple Sclerosis, Kathryn Anne Kern

Dissertations (1934 -)

The pathology of Multiple Sclerosis (MS) is immune-mediated, associated with excessive lymphocyte activity, and dysregulated immune cell metabolism. Biomarkers readily detected in the blood have superior utility in research and the clinical laboratory for their pathological, diagnostic, and prognostic value as well as translatability. There is a need for additional biomarkers of disease status in MS. Therefore, the purpose of this dissertation was to determine whether peripheral blood immune cell (PBMC) metabolism differed between people with MS and non-MS controls, and whether PBMC bioenergetics correlated to muscle energetics and clinical end points including clinical, psychosocial, and functional outcomes. Specific cellular …

Arming The Naked Public Square: America’S Catholic Bishops Confront The Reagan Administration, 1980-1983, Brooke Tranten

Dissertations (1934 -)

This dissertation examines 1983 pastoral on war and peace, The Challenge of Peace, from the National Conference of Catholic Bishops (NCCB). It analyzes in-depth the process of the ad hoc committee of the NCCB that wrote the pastoral alongside the simultaneous debates within the American Catholic community and the Reagan administration surrounding the pastoral. Special attention is given here to the interactions of the Reagan administration with the ad hoc committee, led by Archbishop Joseph Bernardin, and the role of American Catholic lay critics Michael Novak, Philip Lawler, and George Weigel. It also explicates the intrapersonal aspect of drafting process, …

The Mental Health Management Of Individuals In Sex Work, Bianca Tocci

Dissertations (1934 -)

ABSTRACT:

This dissertation examines the mental health implications and experiences of individuals engaged in sex work, employing a constructivist grounded theory approach to explore the nuanced realities of this marginalized population. Through in-depth interviews with sex workers, this study reveals the complex interplay of positive aspects (enjoyment and empowerment), and the negative (severe risks faced by individuals in this field, including verbal abuse, physical violence, and sexual assault). The findings underscore the critical need for a holistic and nuanced understanding of sex work, challenging prevalent stereotypes and emphasizing the importance of ongoing consent, communication, and respect for sex workers' boundaries. …

Monitoring Hydrocarbons In Air Using Adaptive Multivariate Sensor Signal Processing And Analysis Of Humidity Effects, Sakin Sarwar Satter

Dissertations (1934 -)

Volatile organic hydrocarbons such as BTEX (benzene, toluene, ethylbenzene, xylenes), commonly released into the ambient environment from sources such as gasoline or household products, are known to be hazardous to human health. As a result, real-time monitoring of such compounds in ambient environments is required for safety. Gas sensors with high sensitivity, sufficient selectivity, and fast response times are needed for effective monitoring of the environment. This dissertation addresses some challenges in environmental monitoring using gas sensors, especially with multi-analyte mixtures in the presence of humidity. This work uses sensor arrays with multivariable sensing parameters (sensitivity and response time constant) …

Bikeability Disparities In Orange County, California: Intersection Of Place And Demographics, Jeanette Gritton, Maria Cristina Martinez, Georgiana Bostean, Megan Thiele Strong

Faculty Research, Scholarly, and Creative Activity

Active transportation modes such as walking and biking are gaining popularity for their extensive health and environmental benefits, yet scholars know little about how place-based accessibility varies by area sociodemographic composition. This study is among the first to examine sociodemographic disparities (by both race and socioeconomic status) in bikeability while allowing for heterogeneity in disparities. Consideration of bikeability disparities is particularly critical within the framework of urban planning concepts that promote equitable accessibility and reduced dependency on automobiles, such as the 15-minute city. Geographically Weighted Regressions examined associations between census tract-level bikeability (using an index that combines five components), socioeconomic …

Analysis Of Fast-Cured Plastic Scintillator Variations, Andrew K. Nesbitt, John W. Mcclory, Juan J. Manfredi, Andrew W. Decker

Faculty Publications

Organic plastic scintillators are widely used in a variety of homeland security applications, most commonly as detectors for radiation portal monitors due to their relative low cost, physical robustness, and fast-timing properties. However, plastic scintillators also typically provide lower light yields and photon sensitivity compared to other detector material alternatives, so many studies over the past two decades have sought ways to overcome these shortfalls. Research recently conducted at the Air Force Institute of Technology and Oak Ridge National Laboratory demonstrated that photocuring novel plastics offered a viable method for producing fast-curing plastic scintillators (FCPSs). These formulations included an acrylic …

Improved Accuracy And Efficiency Of Primary Care Fall Risk Screening Of Older Adults Using A Machine Learning Approach, Wenyu Song, Nancy K Latham, Luwei Liu, Hannah E Rice, Michael Sainlaire, Lillian Min, Linying Zhang, Tien Thai, Min-Jeoung Kang, Siyun Li, Christian Tejeda, Stuart Lipsitz, Lipika Samal, Diane L Carroll, Lesley Adkison, Lisa Herlihy, Virginia Ryan, David W Bates, Patricia C Dykes

Faculty, Staff and Students Publications

Background: While many falls are preventable, they remain a leading cause of injury and death in older adults. Primary care clinics largely rely on screening questionnaires to identify people at risk of falls. Limitations of standard fall risk screening questionnaires include suboptimal accuracy, missing data, and non-standard formats, which hinder early identification of risk and prevention of fall injury. We used machine learning methods to develop and evaluate electronic health record (EHR)-based tools to identify older adults at risk of fall-related injuries in a primary care population and compared this approach to standard fall screening questionnaires.

Methods: Using patient-level clinical …

Reliable Identification Of Binary Supermassive Black Holes From Rubin Observatory Time-Domain Monitoring, Megan C. Davis, Kaylee E. Grace, Jonathan R. Trump, Jessie C. Runnoe, Amelia Henkel, Laura Blecha, W N. Brandt, J Andrew Casey-Clyde, Maria Charisi, Caitlin A. Witt

Faculty Publications

Periodic signatures in time-domain observations of quasars have been used to search for binary supermassive black holes (SMBHs). These searches, across existing time-domain surveys, have produced several hundred candidates. The general stochastic variability of quasars, however, can masquerade as a false-positive periodic signal, especially when monitoring cadence and duration are limited. In this work, we predict the detectability of binary SMBHs in the upcoming Rubin Observatory Legacy Survey of Space and Time (LSST). We apply computationally inexpensive sinusoidal curve fits to millions of simulated LSST Deep Drilling Field light curves of both single, isolated quasars and binary quasars. The period …

Soil Incubation Methods Lead To Large Differences In Inferred Methane Production Temperature Sensitivity, Zhen Li, Robert F. Grant, Kuang-Yu Chang, Suzanne B. Hodgkins, Jinyun Tang, Alexandra Cory, Zelalem A. Mekonnen, Scott R. Saleska, Eoin L. Brodie, Ruth K. Varner, Virginia I. Rich, Rachel M. Wilson, Jeff P. Chanton, Patrick Crill, William J. Riley

Faculty Publications

Quantifying the temperature sensitivity of methane (CH4) production is crucial for predicting how wetland ecosystems will respond to climate warming. Typically, the temperature sensitivity (often quantified as a Q10 value) is derived from laboratory incubation studies and then used in biogeochemical models. However, studies report wide variation in incubation-inferred Q10 values, with a large portion of this variation remaining unexplained. Here we applied observations in a thawing permafrost peatland (Stordalen Mire) and a well-tested process-rich model (ecosys) to interpret incubation observations and investigate controls on inferred CH4 production temperature sensitivity. We developed a field-storage-incubation modeling approach to mimic the full …

Universal Design For Learning (Udl)- Strategies For Engaging Rural Youth Co-Researchers With Informal Stem Learning, Amanda Bastoni, Jayson Seaman, Andrew D. Coppens, Cindy Hartman, Kate Moscouver, Courtnie Lachaine

Faculty Publications

This article describes methods and findings from a study focused on youth living in rural communities in northern New Hampshire who struggle with accessing STEM learning opportunities for reasons including economic underinvestment and geographical isolation. These challenges also negatively impact researchers hoping to learn how rural youth benefit from informal STEM learning experiences, which contribute to low-project participation and retention rates. As in other amenity-rich rural areas, the communities in this study are promoting outdoor recreation as a vehicle for economic development. We wanted to understand if outdoor recreation activities tied to economic growth initiatives — activities which youth have …

Normalized Ground State Of A Mixed Dispersion Nonlinear Schrodinger Equation With Combined Power-Type Nonlinearities, Zhouji Ma, Xiaojun Chang, Zhaosheng Feng

School of Mathematical & Statistical Sciences Faculty Publications

We study the existence of normalized ground state solutions to a mixed dispersion fourth-order nonlinear Schrodinger equation with combined power-type nonlinearities. By analyzing the subadditivity of the ground state energy with respect to the prescribed mass, we employ a constrained minimization method to establish the existence of ground state that corresponds to a local minimum of the associated functional. Under certain conditions, by studying the monotonicity of ground state energy as the mass varies, we apply the constrained minimization arguments on the Nehari-Pohozaev manifold to prove the existence of normalized ground state solutions.

Pulsed-Power Neutron Production With Deuterated Polymer Accelerator Targets, Anthony O. Hagey, Juan J. Manfredi, Whitman T. Dailey, S. L. Jackson, E. R. Kaiser, J. W. Schumer

Faculty Publications

This document presents an investigation of the effect of deuterated accelerator targets on the neutron fluence from a local mass injection dense plasma focus (LMIDPF) driven by the United States Naval Research Laboratory's (NRL) Hawk pulsed-power generator. Deuterated targets were made using two methods: a well-established thin-film casting technique for flat targets and a more novel additive manufacturing technique that allowed targets to be three-dimensional (3D) printed in both flat and conical geometries. These targets were then tested during neutron-producing experiments conducted using Hawk, and theneutron fluences measured for the various target types were compared. Additive manufacturing was used as …

Patterns Of Comorbidity Of Developmental & Behavioral Problems Among Children In One Family: Impact On Parental Decisions & Need For Services, Ngozi V. Enelamah, Melissa L. Villodas, Andrew Foell, Mansoo Yu, Margaret Lombe, Chrisann Newransky, Von Nebbitt

Faculty Publications

No abstract provided.

What Weight Changes Really Happened During Covid-19 Among Older Adults?, John A Batsis, Dennis T Villareal

Faculty, Staff and Students Publications

No abstract provided.

Chronic Pain And Opioid Addiction - Conservative Options?, Jessy Johnson

Aurora GME

No abstract provided.

On The Origin Of The Sudden Heliospheric Open Magnetic Flux Enhancement During The 2014 Pole Reversal, Stephan G. Heinemann, Mathew J. Owens, Manuela Temmer, James A. Turtle, Charles N. Arge, Carl J. Henney, Jens Pomoell, Eleanna Asvestari, Jon A. Linker, Cooper Downs, Ronald M. Caplan, Stefan J. Hofmeister, Camilla Scolini, Rui F. Pinto, Maria S. Madjarska

Faculty Publications

Coronal holes are recognized as the primary sources of heliospheric open magnetic flux (OMF). However, a noticeable gap exists between in situ measured OMF and that derived from remote-sensing observations of the Sun. In this study, we investigate the OMF evolution and its connection to solar structures throughout 2014, with special emphasis on the period from September to October, where a sudden and significant OMF increase was reported. By deriving the OMF evolution at 1 au, modeling it at the source surface, and analyzing solar photospheric data, we provide a comprehensive analysis of the observed phenomenon. First, we establish a …

Likely Common Coronal Source Of Solar Wind And 3he-Enriched Energetic Particles: Uncoupled Transport From The Low Corona To 0.2 Au, D G. Mitchell, M E. Hill, D J. Mccomas, C M S Cohen, Nathan A. Schwadron, P S. Mostafavi, W H. Matthaeus, N E. Raouafi, S T. Al-Nussirat, D E. Larson, A Rahmati, J C. Kasper, P L. Whittlesey, R Livi, S D. Bale, M Pulupa, J Giacalone, R L. Mcnutt, E R. Christian, M E. Wiedenbeck, T Sharma

Faculty Publications

Parker Solar Probe (PSP) observations of a small dispersive event on 2022 February 27 and 28 indicate scatter-free propagation as the dominant transport mechanism between the low corona and greater than 35 solar radii. The event occurred during unique orbital conditions that prevailed along specific flux tubes that PSP encountered repeatedly between 25 and 35 Rs during outbound orbit 11. This segment of the PSP orbit exhibits almost stationary angular motion relative to the rotating solar surface, such that in the rotating frame, PSP’s motion is essentially radial. The time dispersion often observed in impulsive solar energetic particle (SEP) events …

The Inextricability Of Students’ Mathematical And Physical Reasoning In Quantum Mechanics Problems, Kaitlyn Stephens Serbin, Megan Wawro

School of Mathematical & Statistical Sciences Faculty Publications

Reasoning with mathematics plays an important role in university students’ learning throughout their courses in the scientific disciplines, such as physics. In addition to understanding mathematical concepts and procedures, physics students often must mathematize physical constructs in terms of their associated mathematical structures and interpret mathematical entities in terms of the physical context. In this study, we investigate physics students’ reasoning about mathematics in relation to physics content addressed in two quantum mechanics problems. Through qualitative analysis of interview data from twelve students, results show that 1) students use intricate, nonuniform problem-solving methods with reasoning that moves fluidly between structural …

Prescription And Dispensation Of Qt-Prolonging Medications In Individuals Receiving Hemodialysis, Virginia Wang, Chin-Hua Lily Wang, Magdalene M Assimon, Patrick H Pun, Wolfgang C Winkelmayer, Jennifer E Flythe

Faculty, Staff and Students Publications

IMPORTANCE: Individuals with dialysis-dependent kidney failure have numerous risk factors for medication-related adverse events, including receipt of care by multiple clinicians and initiation of some QT-prolonging medications with known risk of torsades de pointes (TdP), which is associated with higher risk of sudden cardiac death. Little is known about the prescription and dispensation patterns of QT-prolonging medications among people receiving dialysis, hindering efforts to reduce drug-related harm from these and other medications in this high-risk population.

OBJECTIVE: To examine prescription and dispensation patterns of QT-prolonging medications with known TdP risk and selected interacting medications prescribed to individuals receiving hemodialysis.

DESIGN, …

Balancing Wellness And Leadership: Exploring Black Women Administrators’ Subjective Well-Being, Resilience, And Radical Self-Care In Higher Education, Lashae Grottis

Electronic Theses and Dissertations

Leaders in higher education experience high and unrealistic demands for their skills, time, and energy, causing stress, competing priorities, burnout, compromised health, and attrition. However, unlike other racial and gender groups, Black women higher education administrators experienced these challenges more intensely. As a result of chronic stress associated with being undervalued and overworked, discriminatory and unwelcoming workplaces, and intersectional biases, Black women leaders are leaving higher education workplaces. Despite the link between gendered racism and unwellness, little is known about the problem from a positive leadership perspective. This study addressed the lack of knowledge of the wellness strategies Black women …

Best Practices In Professional Learning Communities That Influence Teacher Self-Efficacy, Silian Molly Hornsby

Electronic Theses and Dissertations

This qualitative case study examined best practices in professional learning communities (PLCs) that influence teacher self-efficacy. Participants were primary and intermediate teachers and teacher leaders from a large suburban elementary school in Texas. Participants had to have at least 1 year of teaching and PLC experience. The semistructured teacher and teacher-leader interviews were recorded and transcribed in real time using Otter.ai software. After members checked the transcription, the transcription was uploaded into the NVivo software for coding and identifying common themes. The findings were separated into themes based on the study’s research questions. Research question 1 explored what teachers and …

The Impact Of Gratitude On Academic Advisor Job Satisfaction, Alexandria M. Widener

Electronic Theses and Dissertations

Academic advisors face high job demands and have among the highest turnover rates in higher education. Gratitude may have a positive impact on job satisfaction, but it has not been studied in this population. The purpose of this quantitative correlational study was to understand how dispositional gratitude at work, expression of gratitude at work, and receipt of gratitude at work predict job satisfaction in academic advisors. Academic advisors who were members of NACADA: The Global Community for Academic Advising, served in a full-time role at an institution of higher education in the United States, had worked a minimum of 6 …