Digital Commons Network^™

Seasonal Comparison Of Air Quality Variables And Evaluation Of Carbon Dioxide And Particulate Measurement Period In Classrooms, Daud Nosham

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Indoor air quality and thermal environmental variables were measured in 55 classrooms in the mid-western United States spanning a full academic year. The studied air quality and environmental factors included carbon dioxide, temperature, relative humidity, particle counts, air velocity, formaldehyde, total volatile organic compounds, carbon monoxide, nitrogen dioxide, and ozone.

Carbon dioxide and Particulate matter concentrations were measured for a four-day measurement period. Then one-day, two-day, and four-day occupied time average concentrations were calculated which were then compared statistically to figure out an appropriate measurement period for these air quality variables. Kruskal Wallis test and Wilcoxon test were used to …

International Women Graduate Students: Transition To Public Research Universities In The Midwest, Tran Thanh Truc Nguyen

Department of Educational Administration: Dissertations, Theses, and Student Research

This phenomenological qualitative study explored the experiences of international women graduate students (IWGSs) in transitioning to public research universities in the Midwest. The study utilized Schlossberg’s transition theory (Anderson et al., 2012) to gain insights into the perceptions of six participants during their college transition process. Based on the analysis of data collected through in-depth phenomenological interviews with each participant, three themes emerged that described the challenges faced by the participants during their transition. These themes were: solitary voyage, a dilemma of self-reliance and reliance, and a vicious cycle of limited time and financial constraints. Through the three themes, the …

Strong First Order Electroweak Phase Transitions In The Standard Model With A Real Scalar Singlet Extension, Anthony James Hooper

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The large matter-antimatter asymmetry of the universe and whether the electroweak sector has always been broken are currently unanswered by the standard model (SM). One solution that addresses both these concerns is to impose a strong first order electroweak phase transition (SFOEWPT) and ensure electroweak baryogenesis occurs. Models that undergo a SFOEWPT in the early universe create bubbles of the true vacuum that expand until the universe reaches the vacuum expectation value measured today. If the phase transition is strong enough, then these bubbles may generate a detectable stochastic gravitational wave (GW).

However, the SM by itself can only perform …

Design And Optimization Of A Novel Monolithic Spring For High-Frequency Press-Pack Sic Fet Modules, Bogac Canbaz

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

Silicon Carbide (SiC) Field-Effect Transistor (FET) modules lead the way in power electronics, being superior in efficiency and robustness for high-frequency applications. The shift towards SiC from traditional silicon (Si)-based devices is driven by its superior thermal conductivity, higher electric field strength, and operational efficiency at elevated temperatures. These features are critical for the development of next-generation, grid-oriented power converters aimed at enhancing the reliability and sustainability of power systems. This research focuses on high-frequency press-pack (HFPP) SiC FET modules, addressing the primary challenge of miniaturizing SiC FET dies without compromising performance, through an innovative press-contact design essential for increased …

Talking About Writing: Scenes Of Writing Workshops In History And Practice, Erika Luckert

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation envisions the writing workshop as a space where we do essential political and social work—where we can reimagine writing, and the teaching of writing, in more interdependent and inclusive ways. This research responds to the work of BIPOC writers and scholars who have urged those of us in Writing Studies to address the homogeneity of the workshop’s history, and to revise its exclusionary logics. Drawing on interviews and observations of teachers in undergraduate creative writing and composition classrooms across the United States, the author examines what actually happens when students talk together about their in-progress writing. This dissertation …

Charge And Strain Engineering Of Ferroic And Correlated Oxides, Yifei Hao

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation presents a comprehensive study of the charge and strain effects on the electronic and magnetic properties of epitaxial ferroic and correlated oxide thin films and heterostructures. We perform the planar Hall effect to quantify the magnetocrystalline anisotropy (MCA) in epitaxial La_1-xSr_xMnO₃ films (x = 0.2 and 0.33) deposited on SrTiO₃ substrates. The biaxial magnetic anisotropy energy of L_0.67Sr_0.33MnO₃ is about 17% larger than La_0.8Sr_0.2MnO₃. By comparing with the theoretically predicted values, we have decoupled the doping and strain effects on …

Cultivating Academic Achievement: An Updated Social Psychological Explanation, Maika Malualelagi Tuala

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This study looks at how income differences affect children's social psychological development, which in turn shapes their academic achievement. Building on theories of social class, cultural capital, and self-concept formation, this dissertation offers a new social psychological model that connects parental SES, concerted cultivation, children's academic mindset and achievement. This new concept called “academic mindset” includes several key social-psychological factors that influence academic performance namely- self-esteem, locus of control, math and reading self-concepts, and educational expectations and values. The study uses data from the Early Childhood Longitudinal Study-1998 Kindergarten cohort and tests the model using multivariate regression analyses. Findings show …

Longhand Versus Laptop Note Taking And Lecture Rate Influence, Junrong Lu

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Most college students take lecture notes to prepare for tests. With technology development, more students are recording notes on laptops rather than writing them longhand. Previous studies comparing laptop and longhand note taking mediums yielded mixed results, highlighting the need to identify influencing factors. The present study investigated a potential factor, lecture rate, through two experiments. Experiment 1 examined whether lecture rate differentially influences longhand and laptop note taking without note review. Experiment 2 investigated lecture rate effects before and after note review. Dependent measures pertained to various note-taking indices (e.g., verbatim overlap with lecture transcripts and numbers of words, …

Sun, Thunder, Daugava: Accessible Choral Music From The Latvian Choral Tradition, Paul M. Von Kampen

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

I have been fortunate enough to visit Latvia twice, once in 2009 and again in 2023. With connections made through the global outreach arm of the Lutheran Church Missouri–Synod, I was able to incorporate myself into Latvian culture in ways that may not have been possible had I been a standard tourist. I am grateful to have been invited into the homes of Latvian friends, to have studied in the Jāzeps Vītols Music Academy Library, and to have celebrated both the Jāņi midsummer festival in the Latvian countryside and my twenty-second birthday on the shores of the mighty Daugava River. …

Approximation Via Degree Reduction Of Nonlinearities With Applications To Turbulent Flows, Flame Fronts, And Magnetohydrodynamics, Matthew Enlow

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

We perform an analytical and computational investigation on the effectiveness of a locally bounded truncation function, which we call a calming function, when applied to the nonlinear terms of several dissipative partial differential equations. In particular, the 3D Navier-Stokes equations of incompressible fluid flow, the 2D Kuramoto-Sivashinsky equations of laminar flame fronts, and the 2D MHD-Boussinesq equations of magnetohydrodynamics. Each of these equations have open questions about the global existence and uniqueness of their solutions. These calming functions effectively reduce the algebraic degree of select nonlinear terms, thus one can verify global wellposedness for these "calmed systems." More specifically, in …

Evaluation Of Essential Oils And Their Major Components For Disease Resistance, Serkan Tokgöz

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Essential oils (EOs) are natural hydrophobic compounds, which are highly complex, typically comprising 20 to 60 constituents, with two or three main components making up 20% to 95% of their composition, alongside other minor constituents. Research has firmly established the potent antibacterial and antifungal properties of EOs and their primary components. To assess their efficacy, one EO, nutmeg oil, and seven main components, including safrole, toscanol, safraleine, cinnamaldehyde, carvacrol, carvone, and thymol, were tested against four economically significant fungal pathogens (Alternaria solani, Fusarium graminearum, Rhizoctonia solani, and Sclerotiorum sclerotiorum), one oomycete pathogen (Phytium ultimum …

Next-Generation Crop Monitoring Technologies: Case Studies About Edge Image Processing For Crop Monitoring And Soil Water Property Modeling Via Above-Ground Sensors, Nipuna Chamara

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Artificial Intelligence (AI) has advanced rapidly in the past two decades. Internet of Things (IoT) technology has advanced rapidly during the last decade. Merging these two technologies has immense potential in several industries, including agriculture.

We have identified several research gaps in utilizing IoT technology in agriculture. One problem was the digital divide between rural, unconnected, or limited connected areas and urban areas for utilizing images for decision-making, which has advanced with the growth of AI. Another area for improvement was the farmers' demotivation to use in-situ soil moisture sensors for irrigation decision-making due to inherited installation difficulties. As Nebraska …

Examining Theoretically Derived Mechanisms Underlying The Relationships Between Sexual Arousal, Alcohol Use History, And Sexual Aggression, Kailey Ann Richner

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Various interventions have attempted to reduce the rates of sexual violence perpetrated by college men; however, meta-analyses suggest interventions need to further evaluate theoretically derived mechanisms to improve outcomes (Malamuth et al., 2018; DeGue et al., 2014; Vladutiu, et al., 2011). To address this concern, the present study utilized the Integrated Theory of Sexual Offending (ITSO; Ward et al., 2016; Ward & Beech, 2008; 2006) to explore mechanisms underlying the relationships between sexual arousal, alcohol use history (AUH), and sexual aggression. Working memory, impulsivity, and affective forecasting paradigms were selected to map onto the ITSO’s neuropsychological mechanisms. The interaction between …

Singing While Acting: A Mixed Methods Study Of Classical Singers’ Application Of The Chekhov And Meisner Acting Methods, Amy C. Johnson

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

When considering the minimal acting training incorporated into most voice performance programs, it is understandable why many singers struggle to balance vocal demands with acting demands. Furthermore, the expectations on singers to deliver authentic and nuanced performances are increasing as opera evolves. There is little in-depth understanding of classical singers’ experiences with applying specific acting techniques to their singing. There is also little information about how different acting methods may affect classical singing. This mixed methods collective case study aims to identify the impact of training in a specific acting method on classical singing. The qualitative strand focuses on the …

Surface Chemistry Of Femtosecond Laser Processed Surfaces, Graham Kaufman

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

Micromachining and surface functionalization with femtosecond lasers is a rapidly developing technology in the field of materials and interfacial sciences due to its flexibility towards materials, tunability in surface features, and prospects for scalability. Many interfacial applications have been shown to be enhanced with femtosecond laser-induced surface texturing including two-phase heat transfer, antimicrobial properties, electrochemical systems and more. However, without ideal surface chemistry, the enhancements cannot be optimized for a given application. Surfaces functionalized by femtosecond lasers tend to have transient surface chemistries when exposed to the atmosphere, changing important interfacial properties like the interaction of the solid surfaces and …

Exploring Affective Experiences Of Queer Individuals Navigating Relationships With Evangelical Parents, Grace Pappas

School of Social Work Faculty Publications and Presentations

An abundance of scholarship explores and discusses the process of queer identity development, including the experience of disclosing one’s queer identity, often referred to as coming out. Coming out to one’s parent(s) can be a challenging and complex experience for queer individuals, particularly for children from religious families. In this study, I explored the nuanced relationships between queer individuals and their Evangelical parents. I conducted qualitative interviews with nine participants. Using thematic analysis and Ahmed’s theory of affect and happy objects, I constructed four themes: (a) learning the affect queer carries, (b) feeling the affects of being queer, (c) how …

The Effects Of Partisanship On Legislative Support For Environmental Policies In The United States, Rachel Summers

Department of Environmental Studies: Undergraduate Student Theses

This study investigates the relationship between political partisanship and support for environmental policies at the state level in the United States from the years 2017-2022. To do this, the study focused on two policy areas, water and land, for the average proposed, enacted, and failed bills for all 50 states in the timeframe, with the states categorized as Democratic, swing, or Republican based on the 2016 and 2020 elections. While the study did find that Democratic states were more likely to introduce environmental bills than Republican states, the study also found that there was no statistical difference in the enactment …

Charging Forward: A Comparative Analysis Of Facilitators To Electric Vehicle Adoption In Three U.S. States, Abigail Schroeder

Department of Environmental Studies: Undergraduate Student Theses

Electric vehicles (EVs) are a way to reduce greenhouse gas emissions from transportation, but low consumer adoption rates present a challenge. In order to understand what factors may facilitate EV adoption, a comparative analysis of three U.S. states was performed. These states have the highest rates of EV adoption in the country. Thus, studying them provided insights into what may make EV adoption successful. California, Hawaii, and Washington are the states with the highest EV adoption rates. Based on previous research, a list of 12 characteristics that may influence EV adoption was compiled and applied to each state, focusing on …

Impact Of Pollution On Marginalized Communities: Case Study Of Omaha, Nebraska, Miqaela Davis

Department of Environmental Studies: Undergraduate Student Theses

Environmental justice has been a struggle within our country for years. The goal of Environmental justice is for the fair treatment and equal voice for every single individual regardless of race, income, gender, etc. There has been environmental injustice and racism in many cities, but this study focuses on Omaha, Nebraska. Key questions include: What are some specific pollutants that are prevalent in areas with differing racial majorities in Omaha? What are some of the health patterns in these areas and does it relate to environmental racism? How has Omaha reinforced environmental racism through city planning? Using the Climate and …

Educational Influences On Environmental Perception: A Semester Analysis Of The New Ecological Paradigm Scale In Undergraduates, Zoe Zingler

Department of Environmental Studies: Undergraduate Student Theses

This study evaluated the impact of a geography course, GEOG 181: Global Environmental Issues, at the University of Nebraska-Lincoln on students’ endorsement of the New Ecological Paradigm (NEP) using a pre-course and post-course NEP scale survey. Analyzing paired responses (n = 40) through t-tests and z-scores, only four of 15 statements had statistically significant shifts observed for the entire sample. However, a targeted analysis of students initially possessing lower endorsement of the NEP—early deniers—revealed significant paradigm shifts post-course. While women initially showed stronger NEP endorsement, men demonstrated notable changes following the course towards endorsement of the NEP. Academic majors, whether …

Sliding Markov Decision Processes For Dynamic Task Planning On Uncrewed Aerial Vehicles, Trent Wiens

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Mission and flight planning problems for uncrewed aircraft systems (UASs) are typically large and complex in space and computational requirements. With enough time and computing resources, some of these problems may be solvable offline and then executed during flight. In dynamic or uncertain environments, however, the mission may require online adaptation and replanning. In this work, we will discuss methods of creating MDPs for online applications, and a method of using a sliding resolution and receding horizon approach to build and solve Markov Decision Processes (MDPs) in practical planing applications for UASs. In this strategy, called a Sliding Markov Decision …

Development Of A Multi-Use Modular Microfluidic Platform Using 3d Printing, Carson Emeigh

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Microfluidic lab-on-a-chip (LoC) technology has driven numerous innovations due to their ability to perform laboratory-scale experiments on a single chip using microchannels. Although LoC technology has been innovative, it still suffers from limitations related to its fabrication and design flexibility. Typical LoC fabrication, with photolithography, is time consuming, expensive, and inflexible. To overcome the limitations of LoC devices, modular microfluidic platforms have been developed where multiple microfluidic modules, each with a specific function or group of functions, can be combined on a single platform. Modular microfluidics have overcome some of the limitations of LoC devices, but currently, their fabrication is …

Paying To Reduce Disparity: Financially Incentivizing Workforce Diversity And Its Effects On Managers’ Promotion Decisions And Employees’ Effort, Bret S. Sheeley

College of Business: Dissertations, Theses, and Student Research

Disparities in employee representation persist in higher-level organizational positions despite recent attention to workforce diversity and its associated benefits. In response, companies have begun integrating diversity initiatives with varying degrees of specificity (hereafter, “initiative specificity”) into their managers’ compensation packages to increase underrepresented employees’ representation in higher-level organizational positions. This study uses an experiment to examine how offering managers financial incentives to accomplish diversity initiatives (hereafter, “diversity incentives”) and initiative specificity interact to influence managers’ promotion decisions and employees’ effort choices in a promotion setting.

The results suggest that as underrepresented employees’ pre-promotion efforts increase relative to overrepresented employees’ efforts, …

“Think Leader, Think Alpha Male” And The Evolution Of Leader Stereotypes., Christopher Von Rueden

Jepson School of Leadership Studies articles, book chapters and other publications

Over the past few decades, the representation of women in top leadership positions has steadily increased around the world, yet remains well below gender parity. Do leader stereotypes and preferences still favor men? Based on a series of studies with U.S. participants, Wiezel, Barlev, Martos, and Kenrick (2024) argue that leaders remain stereotyped as male, which is consistent with a “think leader, think alpha-male” model. Inconsistent with the model, the authors also find that women are slightly preferred as leaders, due in part to greater association of men with dominance-based leadership. In general, Wiezel et al. (2024) provide a valuable …

Breakaway Luminaire Pole Research, Jacob Conway

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This document reports the efforts conducted to determine critical parameters and configurations for Manual for Assessing Safety Hardware 2016 (MASH) Test Level 3 (TL-3) compliant breakaway luminaire poles supported by slip bases, including identifying pole configurations with the potential to meet MASH TL-3 as well as recommending critical configurations for full-scale crash testing. A thorough literature review was conducted which included survey results collected from Midwest Pooled Fund state departments of transportation (DOTs), standard plans from state DOT’s, and past luminaire pole testing.

Numerical LS-DYNA models were developed for luminaire poles with 4-bolt slip base utilized by the Utah Department …

Peritextual Elements In Chinese Nonfiction Picturebooks, Sunah Chung, Jongsun Wee, Sohyun Meacham

Faculty Publications

The present work is a comparison of the peritext typology found across various nonfiction picturebooks focusing on Chinese people, including Chinese Americans. Nineteen nonfiction books were chosen following selection methods described in previous literature. Books were individually analysed to see which of five categories they fit under, and insider/outsider status for each author and illustrator was recorded as well. All five types were found in the surveyed Chinese nonfiction picturebooks; however, none of the books encouraged readers to take action for social change. We also found slight variation in peritext usage between the insiders and outsiders for authors and illustrators. …

Characterization Of Fibronectin Adhesion Isolated Dental Pulp Progenitor Cell Populations, Heoijin Kim

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: The DPSC constitutes a significantly small population, comprising approximately 1% of the total cells in the pulp tissue. Therefore, it is imperative to successfully culture and populate DPSCs in vitro before utilizing them for therapeutic purposes. Understanding DPSC heterogeneity is crucial for innovative regenerative therapies, prompting the investigation of mixed populations using fibronectin as a biological marker. It is reported that cellular phenotype and biological function may undergo alterations as cells replicate in a cultured environment or the substrate to which the cells adhere.

Objectives: In this study, we compared and analyzed the impact of various isolation methods on …

Analyses Of Thermal And Spectral Characteristics Of Artificial Turf And Natural Grass In Las Vegas Valley, Tarannum Kalam Khandoker

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis presents a comprehensive analysis of the thermal and spectral characteristics of Las Vegas Valley (LVV). The first objective examines the effects of artificial turf on the urban thermal environment in the LVV by analyzing the impact of Land Surface Temperature (LST) and surface albedo at 26 ROIs that transitioned from natural to artificial turf, alongside another 26 ROIs that remained unchanged between 2018 and 2022 utilizing available Landsat 8 satellite images for the respective years. In the comprehensive comparison of ROIs over the two years in question, it was observed that transitioning to artificial turf correlated with elevated …

Investigative Research On Design Parameters And Criticality Models For Microreactors, Cameron Jensen

UNLV Theses, Dissertations, Professional Papers, and Capstones

With increased energy demand and the desire to reduce reliance on fossil fuels, nuclear power will need to play a prominent role in achieving carbon-free energy independence. Large nuclear reactors are necessary to meet this objective. However, they are expensive and take a long time to build. For remote locations (e.g., military bases) and smaller communities, large nuclear reactors would not be feasible or cost effective. Small reactors (microreactors) can fill this necessary gap. These reactors would be factory-built, delivered quickly, and operated with high intrinsic levels of safety. With microreactors still in conceptual and testing states, there is a …

The Effect Of Transcranial Direct Current Stimulation Of The Dorsolateral Prefrontal Cortex On Muscle Fatigue Resistance, Taylie Thompson Liddell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Transcranial direct current stimulation (tDCS) delivered to the dorsolateral prefrontal cortex (DLPFC) can increase endurance time in lower body cycling tasks. The purpose was to examine the effect of DLPFC-tDCS on the time to task failure (TTF) of a fatiguing contraction performed by hand muscles. The study used a double-blind, randomized, SHAM-controlled, crossover design. Participants completed two experimental sessions on separate days with a washout between sessions. All facets of the experiments were identical except the stimulation condition (DLPFC-tDCS or SHAM) that was given concurrent with the fatiguing contraction. The fatiguing contraction involved gripping a manipulandum with the index finger …