Digital Commons Network^™

Hybrid Two Dimensional Quantum Devices, Joshua Patrick Thompson

Graduate Theses and Dissertations

This thesis describes measurements on hybrid material systems involving two dimensional (2D) materials and phenomena along with the development of a small, hermetically sealed cell. The hermetic cell is designed to assist with analyzing sensitive 2D materials outside of an inert environment. When working with van der Waals materials that are especially sensitive to oxygen or water, it can be difficult to identify usable thin flakes without exposing them to air. To help preserve materials for analysis in air, a capsule was designed that isolates the material in an inert environment. Although the capsule is hermetically sealed, the encapsulated material …

The Effects Of Commercial Harvest On The Density And Demography Of Aquatic Turtles In Arkansas, Andrhea Darleen Massey

Graduate Theses and Dissertations

The United States is home to the second highest concentration of turtle species in the world, after Asia. As of 2018, there are 57 turtle species recognized within the US, 40% of which are listed as threatened or endangered, with the primary threats to population persistence identified as over-consumption and/or habitat loss. Within the US, the Mississippi Alluvial Valley (MAV) region represents the second highest turtle species richness, after the Mobile River Basin. The MAV region of Arkansas is one of the least regulated in terms of commercial aquatic turtle harvest and has undergone large-scale habitat conversion from bottomland hardwood …

Reflective Conversations: Exploring Faculty’S Perceptions Of Reflection To Enhance Teaching Effectiveness, Jonna Lynn Myers

Graduate Theses and Dissertations

The purpose of this pragmatic qualitative research study is to examine the impact of a faculty development program’s reflection component on teaching effectiveness as perceived by the faculty participants. This study utilizes Schön’s (1983) reflective practice, which calls professionals to move from the technical rationality position of development and practice (theoretical and detached) into a reflective position (practical and applicable). Schön contends that this movement occurs by focusing on reflection in the forms of reflection-in-action, reflection-on-action, and reflective conversations. This study specifically examines the reflection component embedded into the inaugural class of the Excellence in Teaching Program (ETP) at pseudonymous …

Detrital Zircon U-Pb Geochronology Of Upper Mississippian Siltstone, Oklahoma And Arkansas, Linnea Johnson

Graduate Theses and Dissertations

Although Upper Mississippian strata have been characterized extensively using lithostratigraphy, sequence stratigraphy, and biostratigraphy across the North American midcontinent, the origin of the silt comprising the Meramec STACK (Sooner Trend Anadarko Basin, Canadian and Kingfisher counties) reservoirs of the Anadarko Basin in west-central Oklahoma and age equivalent units is not well understood, despite its economic importance as an unconventional petroleum reservoir. Previously published models have variously invoked fluvial, marine, and aeolian sediment transport for Upper Mississippian siltstone present along the paleo-shelf edge of the Laurentian craton. This study uses detrital zircon U-Pb geochronology and grain morphology, handheld x-ray fluorescence (hXRF) …

Machine Learning Applied To A Modern-Pleistocene Petrographic Dataset: The Global Prediction Of Sand Mineralogy (Gloprsm) Model, Isaac Johnson

Graduate Theses and Dissertations

Petrography has long been used as a tool to decipher the sedimentary provenance of sand and sandstone from the relative proportions of framework grain types. Petrographers have also related the proportions of quartz (Q), feldspar (F), and lithic (L) grains to the processes that form and modify sediments within sediment routing systems. This past work has shown that factors including source lithology, climate, transport history, and tectonism work in concert to modify the framework mineralogy of sand. However, there is a lack of a quantitative understanding of the interactions and feedbacks between these factors and how they modify sand mineralogy. …

Incorporation Of Zinc In Pre-Alloyed Cuin[Zn]S2/Zns Quantum Dots, Jean Carlos Morales Orocu

Graduate Theses and Dissertations

Since the early 2000s heavy-metal-free quantum dots (QDs) such as CuInS2/ZnS have attempted to replace CdSe, their heavy-metal-containing counterparts. CuInS2/ZnS is synthesized in a two-step process that involves the fabrication of CuInS2 (CIS) nanocrystals (NCs) followed by the addition of zinc precursors. Instead of the usual core/shell architecture often exhibited by binary QDs, coating CIS QDs results in alloyed and/or partially alloyed cation-exchange (CATEX) QDs. The effect that zinc has on the properties of CIS NCs was studied by incorporating zinc during the first step of the synthesis. Different In:Cu:Zn ratios were employed in this study, maintaining a constant 4:1 …

Design, Synthesis, And Catalytic Application Of Crystalline Porous Nanomaterials, Zainab Abdullah Almansaf

Graduate Theses and Dissertations

Chapter 1: COFs (covalent organic frameworks) are a new type of microporous crystalline polymer connected by organic units via strong covalent bonds. Due to their well-defined crystalline structures and excellent chemical and thermal stabilities, COF materials are considered promising candidates in applications such as gas adsorption, catalysis, and energy storage.Chapter 2: A new covalent organic framework (COF) based on imine bonds was assembled from 2-(4-formylphenyl)-5-formylpyridine and 1,3,6,8-tetrakis(4-aminophenyl)pyrene, which showed an interesting dual-pore structure with high crystallinity. Postmetallation of the COF with Pt occurred selectively at the N donor (imine and pyridyl) in the larger pores. The metalated COF served as …

Mapping The Pathways To Campus Writing Sites: Implications For Writing Program Administrators, Meagon Clarkson-Guyll

Graduate Theses and Dissertations

This dissertation investigates the extent to which the writing program administrator and their affiliated writing program are structurally, organizationally, and rhetorically visibly connected to other campus sites of writing. To complete this project data was collected across five benchmarked institutions from publicly accessible online texts. Rhetorical analysis, informed by rhetorical genre studies and institutional ethnography, was conducted to conclude how writing programs are rhetorically situated in their home campus and how the role of the writing program administrator is rhetorically shaped within institutional structures and texts. The analysis concludes with recommended authorial interventions for the writing program administrator to adapt …

Body Mass And Body Condition Variation Of Mallards (Anas Platyrhynchos) Within And Among Winters Within The Lower Mississippi Alluvial Valley, John Thompson Veon

Graduate Theses and Dissertations

Most North American waterfowl overwinter in southern North America before migrating back to breeding grounds in the northern US and Canada. These species face the challenge of needing to maintain or increase their body mass during an environmentally difficult winter period. Successful body mass maintenance during the winter period has major ramifications not only for their winter survival but for their fitness across the entire year. Recent research in Europe and the western United States suggests that the body mass of mallards (Anas platyrhynchos) has increased from the late 1960s to early 2000s. However, the factors responsible for increases in …

Development And Characterization Of Monolayer And Sub-Monolayer Intermediate Band Solar Cells, Najla Alnami

Graduate Theses and Dissertations

Intermediate band solar cell (IBSC) is a new generation solar cell that is designed to overcome the main limitation of solar cell power conversion efficiency, which is the non-absorption of low photon energy. Experimental efforts towards fabricating high efficiency and low cost IBSC have not met the predictions of theoretical analysis. Existing implementations of the IBSC design using conventional Stranski-Krastanov (S-K) quantum dots (QDs) have resulted in a degradation in the solar cell device characteristics, which has been found to be caused by recapturing or trapping of excess carriers, low intermediate band material absorption, and increased recombination in the solar …

Gaas Growth On Sapphire Substrates (C And R Plane) For Integrated Microwave Photonics (Imwp), Samir Kumar Saha

Graduate Theses and Dissertations

The microwave signal processing in the optical domain creates new opportunities for information and communication technology (ICT) and networks by increasing speed, bandwidth, and processing capability. IMWP incorporates the functions of microwave photonics components/subsystems in monolithic or hybrid photonic circuits to meet future needs. Sapphire platforms have the potential to integrate all-in-one, for instance, light source, analog signal processing, light detection, CMOS control circuit, silicon on sapphire to achieve high-performance, low-cost mixed-signal optical links etc. Molecular beam epitaxy (MBE) has been used to grow GaAs on sapphire substrates to integrate optoelectronic devices in the same platform.

The initial stage of …

Two-Dimensional Black Phosphorus For Terahertz Emission And Near-Field Radiative Heat Transfer, Mahmudul Hasan Doha

Graduate Theses and Dissertations

The main focus of this work is to investigate two potential optical and optoelectronic applications of black phosphorus (BP): the near-field radiative heat transfer in plasmonic heterostructures with graphene and terahertz emission from multi-layer BP photoconductive antennas. When the separation distance between graphene-black phosphorene is much smaller than or comparable to the thermal wavelength at different temperatures, a near-field radiation heat transfer breaks the Planck blackbody limit. The magnitude of the near-field radiation enhancement acutely depends on the gate voltage, doping, and vacuum gap of the graphene and BP pair. The strong near-field radiation heat transfer enhancement of the specific …

Remixed, Remastered: Investigating Organizational Adaptation In Higher Music Education, Jacob Bruce Hertzog

Graduate Theses and Dissertations

Higher music education presents a unique opportunity to examine change within higher education due to the digital revolution in the music industry over the past two decades. The purpose for conducting this study was to describe, map, and explain the strategies that higher music education programs are using to adapt to the digital revolution in the music industry. This study was grounded in organizational adaptation theory, drawing upon nine well-established theories: population ecology, life cycles, strategic choice, isomorphism, symbolic action, resource dependence, cybernetics, and network theory. Critical concepts of the turbulent environment, environmental perception, and organizational adaptation strategy emerged from …

Experimental And Computational Studies Of Electron Rich Alkenes, Alexa May

Graduate Theses and Dissertations

Thermal homolysis is one of the most fundamental reactions in organic chemistry. Free radical reactions are generally initiated by light or a radical initiator to generate the first radical, which can then propagate or terminate the reaction. Direct thermal homolysis requires no chemical initiators, just an increase in temperature depending on the homolysis energy.There are few studies of direct radical homolysis in complex systems or under mild conditions. The reactions involving C-N homolysis under mild conditions are reported in Chapter 1. Though the authors do not all propose a radical mechanism, we believe they can all be explained by a …

A Causal Comparative Study Of Stem Persistence Between Supported And Non-Supported Stem Interested Students, Elizabeth Bernardi

Electronic Theses and Dissertations

Many students who enter a STEM track in college move out of that track before graduation (National Science Foundation, 2018). The purpose of this study was to assess whether there was a difference in STEM-related major persistence for population proportions of students actively involved in the Science Scholars program and those who were STEM-interested but not program participants. This program oriented students to the STEM program, facilitated engagement with peers and faculty, exposed students to research opportunities, and filled in potential learning gaps (Gibson et al., 2019).

The questions guiding the current research included:

Q1. Was there a statistically significant …

The Morphodynamic Interaction Of River Deltas And Their Marshes, Kelly M. Sanks

Graduate Theses and Dissertations

Globally, many of the largest river deltas contain vast marsh platforms that are currently threatened due to a combination of anthropogenic alterations to rivers and increasing relative sea level rise. Restoration and management plans for river deltas depend on optimizing riverine sediment accumulation in marsh platforms. However, the accumulation of organic material in marsh platforms is often neglected in predictive models and the interaction of ecogeomorphic processes governing marsh accumulation with the physical processes governing river delta growth is poorly understood.

Herein, I investigate this complex relationship through a combination of field and experimental studies. I show that in coastal …

Analysis Of Bacteriorhodopsin Suspended In A Bilayer Lipid Membrane, Moath Alhejji

Graduate Theses and Dissertations

The bacteriorhodopsin protein’s unique characteristic of proton pumping can convert light energy to electric energy. The aim of this research was to generate photocurrent using bacteriorhodopsin in a bi-layer lipid membrane. Lipid monolayer and bilayer were formed using painting and folding methods, respectively. Capacitance and resistance of the lipid membranes were measured and used to validate the best methodology. My results show that the folding method is more efficient in incorporating Bacteriorhodopsin. The photocurrent was generated by illuminating a green laser (532 nm) on the bilayer lipid membranes. The patch clamp electrophysiology technique was used to apply voltage across the …

Automated Flight Controller Adaptive Compensation For Actuator Failures In Transport Type Aircraft, Daniel James Fresella

Graduate Theses and Dissertations

Aircraft operate over a wide range of conditions including atmospheric, weight, and center ofgravity changes. This presents a substantial challenge to automatic control system designers. When these operating conditions are merged with a partial or full control surface failure, automatic flight control is near impossible with conventional controllers. Additionally, when pilots experience control failure emergencies during flight, workload and fatigue increase drastically. The continued research of automatic flight control systems that can seamlessly adapt to unmodelled failures will enable a new generation of robust aircraft control. In this paper a 9th order 6 degree of freedom aircraft model is used …

Fair And Diverse Group Formation Based On Multidimensional Features, Mohammed Saad A Alqahtani

Graduate Theses and Dissertations

The goal of group formation is to build a team to accomplish a specific task. Algorithms are being developed to improve the team's effectiveness so formed and the efficiency of the group selection process. However, there is concern that team formation algorithms could be biased against minorities due to the algorithms themselves or the data on which they are trained. Hence, it is essential to build fair team formation systems that incorporate demographic information into the process of building the group. Although there has been extensive work on modeling individuals’ expertise for expert recommendation and/or team formation, there has been …

Catalytic Activity Of Molybdenum-Dioxo Complexes, Randy Tran

Graduate Theses and Dissertations

This dissertation details the development of rationally designed dioxomolybdenum catalyst active for deoxydehydration (DODH), the net reduction of diols and polyols into alkenes and dienes. Catalyst design involved variations on dioxomolybdenum(VI) supported by a dianionic meridional pincer ligand. Rational substrate scope was explored using aliphatic diols, aromatic diols, and biomass derived diols. Various reductants were tested for ability to catalyze the reaction. The substrate specific mechanism of DODH was explored utilizing NMR and in-situ infrared spectroscopy and important rate constants and rate determining steps were found to aid in the optimization of ideal reaction conditions. Catalytic activity was observed to …

Parenting The Gifted: Caregivers’ Perspectives Of Challenges And Their Confidence To Support Their Exceptional Children, Kristi A. Mascher

Graduate Theses and Dissertations

This phenomenological study uses Bandura’s theory of self-efficacy (1977) to examine the lived experiences of eight parents of gifted children and how their experiences, both positive and negative, shape their perception of their confidence and may contribute to building future supports for gifted parents and caregivers. Qualitative data, collected through semi-structured interviews and analyzed with an interpretive/hermeneutic lens, provides seven major themes derived from the voices of parents with children of varying ages and exceptionalities. In addition, this study concludes with a discussion surrounding the additional challenges associated with parenting the exceptional, frameworks for gifted parent support systems, as well …

The Nature Of Informal Educators In Science Centers, Science Museums And Zoos: Case Studies Of Personnel, Practices, Programs, Outreach And Organization, Courtney Erickson

Graduate Theses and Dissertations

Informal Science Centers provide educational experiences for people across the country daily. While the terminology is often similar, there are differences between institutions, often determined by mission, organizational structure, and experience. The purpose of this study was to identify shared experiences and unique characteristics of eight informal science centers around the country. The significance of the study was to add to the understanding of informal science educators' responsibilities, organizational structure, decision-making process, and development. Data for the study was collected using qualitative measures through a researcher-created interview, sent to fifteen institutions, after the recommendation from two well-known informal science researchers. …

Adapting Animals: Nineteenth-Century British Literature, Science, And Media, Kristen Layne Figgins

Graduate Theses and Dissertations

In the nineteenth century, Charles Darwin and other proponents of evolutionary theory provided a theoretical framework for discussing the question of humanity’s place in the world. These nascent theories emphasized the shared animal nature of humans and the nonhuman creatures who had once occupied a distinctly lower place on the chain of being. My dissertation addresses the question of how nineteenth-century scientific attitudes about animals were reflected in the literature of the period. By examining culture-texts from the nineteenth century, it is clear that literature was an active participant in extending scientific knowledge, often by playing with the blending categorical …

The Use Of Singlebeam Echo-Sounder Depth Data To Produce Demersal Fish Distribution Models That Are Comparable To Models Produced Using Multibeam Echo-Sounder Depth, Marcela Montserrat Landero Figueroa, Miles J. G. Parsons, Benjamin J. Saunders, Ben Radford, Chandra Salgado-Kent, Iain M. Parnum

Research outputs 2014 to 2021

Seafloor characteristics can help in the prediction of fish distribution, which is required for fisheries and conservation management. Despite this, only 5%–10% of the world's seafloor has been mapped at high resolution, as it is a time-consuming and expensive process. Multibeam echo-sounders (MBES) can produce high-resolution bathymetry and a broad swath coverage of the seafloor, but require greater financial and technical resources for operation and data analysis than singlebeam echo-sounders (SBES). In contrast, SBES provide comparatively limited spatial coverage, as only a single measurement is made from directly under the vessel. Thus, producing a continuous map requires interpolation to fill …

Duty To Address Climate Change Litigation Risks For Australian Energy Companies—Policy And Governance Issues, Prafula Pearce

Research outputs 2014 to 2021

The transition from fossil fuels to renewable energy requires cooperation from all, including corporations, shareholders, and institutional investors. The purpose of this paper is to explore climate change litigation risks for Australian energy companies and investors from a policy and governance perspective. Companies are increasingly reporting their climate policies to satisfy their shareholders and investor demands. In addition, the government and judiciary are making laws and decisions to support the Paris Agreement. This paper explores whether company directors can and, in some cases, should be considering the impact of climate change litigation risks on their business, or else risk breaching …

Nano-Grating Assisted Light Absorption Enhancement For Msm-Pds Performance Improvement: An Updated Review, Narottam Das, Mohammad Nur-E-Alam, Alif Islam, Ain Zulaikha Maslihan Ain

Research outputs 2014 to 2021

The primary focus of this review article mainly emphasizes the light absorption enhancement for various nanostructured gratings assisted metal-semiconductor-metal photodetectors (MSM-PDs) that are so far proposed and developed for the improvement of light capturing performance. The MSM-PDs are considered as one of the key elements in the optical and high-speed communication systems for applications such as faster optical fiber communication systems, sensor networks, high-speed chip-to-chip interconnects, and high-speed sampling. The light absorption enhancement makes the MSM-PDs an ideal candidate due to their excellent performances in detection, especially in satisfying the high-speed or high-performance device requirements. The nano-grating assisted MSM-PDs are …

Investigating Strike-Slip Faulting Parallel To The Icelandic Plate Boundary Using Boundary Element Models, Anna E.R. Pearson, John P. Loveless

Geosciences: Faculty Publications

Most faults in Iceland strike roughly parallel to the divergent plate boundary, a part of the North American-Eurasian plate boundary, which would be expected to lead to primarily normal faulting. However, several studies have observed a significant component of rift-parallel strike-slip faulting in Iceland. To investigate these fault kinematics, we use the boundary element method to model fault slip and crustal stress patterns of the Icelandic tectonic system, including a spherical hotspot and uniaxial stress that represents rifting. On a network of faults, we estimate the slip required to relieve traction imposed by hotspot inflation and remote rifting stress and …

Genome Annotation Using Average Mutual Information, Garin P. Newcomb

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Advancements in high-throughput DNA sequencing technologies and ambitious goals for their use are resulting in the generation of a deluge of unannotated sequenced genomes. This makes computational tools that can aid in annotation increasingly valuable.

Here, we provide a detailed exploration of the utility as well as the limitations of average mutual information (AMI) in several steps of genome annotation. For a genomic sequence, AMI is a measure of the information a base contains about the base separated by a fixed lag. A profile is constructed by calculating AMI at multiple lags. In addition to traditional AMI, we employ two …

Risk-Based Machine Learning Approaches For Probabilistic Transient Stability, Umair Shahzad

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Power systems are getting more complex than ever and are consequently operating close to their limit of stability. Moreover, with the increasing demand of renewable wind generation, and the requirement to maintain a secure power system, the importance of transient stability cannot be overestimated. Considering its significance in power system security, it is important to propose a different approach for enhancing the transient stability, considering uncertainties. Current deterministic industry practices of transient stability assessment ignore the probabilistic nature of variables (fault type, fault location, fault clearing time, etc.). These approaches typically provide a conservative criterion and can result in expensive …

Order And Harmony: Kepler’S Guiding Forces, Dan Broadbent

Faculty Publications

Adapted from the article “Order and Harmony: Kepler’s Guiding Forces” included in “Towards Mysteries of the Cosmos with Johannes Kepler – on the 450th Anniversary of His Birth,” a commemorative volume published by the Obserwatorium Atronommiczne Krolowej Jadwigi Rzepienniku Biskupim (Queen Jadwiga Observatory of Rzepiennik Biskupi Poland) December 2021. Adapted with permission.

As the subject librarian for physics and astronomy at Brigham Young University, the author has had the privilege of handling some of Johannes Kepler’s original books preserved in the university’s archives. One of the most impressive materials in the archive is a large page from Mysterium Cosmographicum that …