Digital Commons Network^™

An Analysis Of The Impact Of Strict Photo Id Laws On Election Turnout: Do They Discriminate Against Minority Voters?, Josh Gromowsky

Honors Program: Senior Projects (Public)

Over the last 20 years, states across the nation have passed photo ID laws requiring potential voters to provide a form of identification before they can cast their ballots. These laws have generated great controversy, with opponents of the laws accusing them of being racially discriminatory. Studies attempting to analyze their effects on turnout have resulted in differing results due to different methodologies, and no consensus has been reached in the academic literature regarding this topic. Recognizing that laws do not exist in isolation and that people can react to their implementation in different ways, this paper examines the effects …

Innovation For The Air: A Brief History Of Worldwide Aviation, Lauren Plumley

Honors Program: Senior Projects (Public)

The purpose of this report is to present a brief but comprehensive overview of the variety of innovations related to aviation, and to discuss their impact on scientific progress over the course of human history. Relevant discoveries from the fields of physics and aerodynamics, and the numerous technologies built based upon these discoveries, are discussed over a period ranging from ancient times to the twenty-first century. The scope of this report is an overview of the development of powered and unpowered aircraft, including lighter-than-air, heavier-than-air, and aerospace technologies. Aviation developments were generally not limited to one specific country or person, …

Prefix-Rewriting: The Falsification By Fellow Traveler Property And Practical Computation, Ash Declerk

Department of Mathematics: Dissertations, Theses, and Student Research

The word problem is one of the fundamental areas of research in infinite group theory, and rewriting systems (including finite convergent rewriting systems, automatic structures, and autostackable structures) are key approaches to working on the word problem. In this dissertation, we discuss two approaches to creating bounded regular convergent prefix-rewriting systems.

Groups with the falsification by fellow traveler property are known to have solvable word problem, but they are not known to be automatic or to have finite convergent rewriting systems. We show that groups with this geometric property are geodesically autostackable. As a key part of proving this, we …

Making Mistakes: Children’S Errors As Opportunities For Emergent Literacy Learning In Early Childhood, Clariebelle Gabas, Laura Cutler, Rachel E. Schachter

Department of Child, Youth, and Family Studies: Faculty Publications

Errors are a natural part of children’s knowledge building and learning experiences in early childhood (EC). Importantly, errors can be a powerful tool for tailoring instruction to children’s specific needs and supporting learning processes (Seifried & Wuttke, 2010). The leveraging of errors to support children’s emergent literacy learning became apparent to us when we examined data from a recent observational study of teachers’ practices in EC classrooms with children 3–5 years old. In our study of 400 classrooms, we identified the 30 classrooms in which children demonstrated the highest language gains and the 30 classrooms in which children demonstrated the …

Modeling And Visualization Of Competing Escalation Dynamics: A Multilayer Multiagent Network Approach, Josh Allen

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

Recent advances in military technology, such as hypersonic missiles, which can travel at more than five times the speed of sound and descend quickly into the atmosphere, give world nuclear superpowers a new edge. These advances up the game for nuclear superpowers with an extremely rapid, intense burst of military striking capability to secure upfront gains before encountering potentially overwhelming military confrontation. However, this so-called fait accompli has not been systematically studied by the United States in the perspective of the escalation philosophies of nuclear power competitors, or the mathematical modeling and visualization of multi-modal escalation dynamics. This gap may …

Leveraging Aruco Fiducial Marker System For Bridge Displacement Estimation Using Unmanned Aerial Vehicles, Mohamed Aly

School of Computing: Dissertations, Theses, and Student Research

The use of unmanned aerial vehicles (UAVs) in construction sites has been widely growing for surveying and inspection purposes. Their mobility and agility have enabled engineers to use UAVs in Structural Health Monitoring (SHM) applications to overcome the limitations of traditional approaches that require labor-intensive installation, extended time, and long-term maintenance. One of the critical applications of SHM is measuring bridge deflections during the bridge operation period. Due to the complex remote sites of bridges, remote sensing techniques, such as camera-equipped drones, can facilitate measuring bridge deflections. This work takes a step to build a pipeline using the state-of-the-art computer …

Sim-To-Real Reinforcement Learning Framework For Autonomous Aerial Leaf Sampling, Ashraful Islam

School of Computing: Dissertations, Theses, and Student Research

Using unmanned aerial systems (UAS) for leaf sampling is contributing to a better understanding of the influence of climate change on plant species, and the dynamics of forest ecology by studying hard-to-reach tree canopies. Currently, multiple skilled operators are required for UAS maneuvering and using the leaf sampling tool. This often limits sampling to only the canopy top or periphery. Sim-to-real reinforcement learning (RL) can be leveraged to tackle challenges in the autonomous operation of aerial leaf sampling in the changing environment of a tree canopy. However, trans- ferring an RL controller that is learned in simulation to real UAS …

Irrigation-As-A-Service For Smallholder Farmers, Ishani Lal

Department of Agricultural Economics: Dissertations, Theses, and Student Research

Irrigation is a crucial management practice that can help increase food security among smallholders globally while mitigating climate change impacts. High-efficiency irrigation technologies such as drip kits and sprinkler systems are relatively expensive and smallholder farmers cannot afford them to buffer crop yields against low precipitation. In many developing countries, farmers participate in robust informal markets for renting and sharing of irrigation equipment. Such services may be operated by farmers or via a third party such as irrigation start-ups, water user associations, non-governmental organizations, or even government agencies. These services are referred to collectively as Irrigation-as-a-Service (IaaS).

The objective of …

Summer Bridge Programs In National And Local Context, Osvaldo Palma Vargas

Honors Program: Senior Projects (Public)

Research suggests that summer bridge programs (SBPs) meet their intended goal, which is to improve first-generation students’ academic outcomes as defined by first-year retention and GPA. However, we know little about whether, and if so, how SBPs optimize the implementation of known best practices and how they are perceived by participating students. This thesis compares evidence regarding key practices of SBPs at a selection of Land Grant institutions, to identify commonalities and differences. In addition, this thesis compares the key practices of these peer institutions with a local SBP in place at the University of Nebraska-Lincoln, known as the Nebraska …

Magnetic Properties Of Polycrystalline Spinel Oxides From Solid State Reaction, Camden Olds

Honors Program: Senior Projects (Public)

Spinel crystal materials of nickel, cobalt, and iron oxides have seen abundant research for their strong conductivity, ferromagnetic and ferroelectric properties, and their catalytic uses. These can be synthesized by a number of means. This project explores the use of the solid state synthesis method, which benefits from simplicity, of this family of materials, looking for interesting phase shift lines in the triangle between of varying compositions of these three metals.

Nickel cobaltite and other related spinels were synthesized from two different solid state approaches and characterized using XRD and SQUID magnetometry. The range 0.5-0.6 of molar ratios of nickel …

Modeled Uranium Series Disequilibria In A Heterogeneous Mantle Underlying Iceland, Dana Andersen

Honors Program: Senior Projects (Public)

Regional lithologic heterogeneities in Earth’s mantle may significantly contribute to variations in magma productivity and crustal generation. Such heterogeneities may be a key factor in the anomalously high rates of magmatism and thickened crust of Iceland, which are not fully explained by the presence of a mantle plume. However, the exact lithologic composition of the mantle underlying Iceland is largely unknown. Recent trace element modeling has suggested a two-component melt source beneath Iceland, consisting of a typical upper mantle peridotite mixing with one of several compositions of pyroxenitic material. This study further investigates these potential melt sources by calculating U-series …

The Impact Of An Inquiry-Based Learning Professional Development Has On Science And Agricultural Teachers' Intent To Use Animal Science Concepts As A Context For Teaching Science, Kasey Harmon

Department of Agricultural Leadership, Education, and Communication: Dissertations, Theses, and Student Research

There is an emerging need for Tennessee and Nebraska high school students to increase their science proficiency. It is important that students are science literate to equip them with basic science skills needed for the workforce. Science literacy enables students to problem solve efficiently, appropriately assess societal issues, and make informed decisions. Inquiry-based learning (IBL) is a teaching strategy that has been shown to positively impact students’ ability to critically think and make informed decisions. Since IBL and agricultural education are centered around experiential learning, combining them gives students the opportunity to learn science in a real-world context. However, previous …

Studying Developer Eye Movements To Measure Cognitive Workload And Visual Effort For Expertise Assessment, Salwa D. Aljehane, Bonita Sharif, Jonathan I. Maletic

School of Computing: Faculty Publications

Eye movement data provides valuable insights that help test hypotheses about a software developer’s comprehension process. The pupillary response is successfully used to assess mental processing effort and attentional focus. Relatively little is known about the impact of expertise level in cognitive effort during programming tasks. This paper presents a quantitative analysis that compares the eye movements of 207 experts and novices collected while solving program comprehension tasks. The goal is to examine changes of developers’ eye movement metrics in accordance with their expertise. The results indicate significant increase in pupil size with the novice group compared to the experts, …

Optimal R&D Investment In The Management Of Invasive Species, William Haden Chomphosy, Dale T. Manning, Stephanie A. Shwiff, Stephan Weiler

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive alien species (IAS) threaten world biodiversity, ecosystem services, and economic welfare. While existing literature has characterized the optimal control of an established IAS, it has not considered how research and development (R&D) into new removal methods or technologies can affect management decisions and costs over time. R&D can lower the costs of control in a management plan and creates an intertemporal trade-off between quick but costly control and gradual but cheaper removal over time. In this paper, we develop and solve a continuous time dynamic optimization model to study how investment in R&D influences the optimal control of an …

Physiological Response To Political Messaging, Kelsey Wright

Honors Program: Senior Projects (Public)

The overall goal of this study was to understand if individuals who politically identify as Democrats or Republicans have a statistically significant difference in their emotional response to congruent and incongruent political media clips. I used physiological measures of arousal, valence, and emotional control to understand threat response while participants watched congruent and incongruent political media clips. There was no significant difference between the response to congruent and incongruent media in individuals who identify as Democratic or Republican. There was no significant difference in physiological measures when individuals viewed congruent media clips than viewing incongruent media clips. However, there was …

Recycling Attitudes And Behaviors Toward Single-Use Plastics At The University Of Nebraska–Lincoln, Jadyn Chasek

Department of Environmental Studies: Undergraduate Student Theses

Today, single-use plastics pose an issue in the world with pollution from improper disposal as well as from the manufacturing of single-use plastic products. There is a need for change, plastic products have begun to consume the planet and harm life on Earth. Many people look to college universities for an opportunity to change issues such as the overconsumption of single-use plastics. A college campus is the perfect environment to study what changes can be made to fix an issue as well as how to implement those changes. This study was conducted at the University of Nebraska-Lincoln, where the undergraduate …

Amazon Deforestation And Its Effects On Local Climate, Andrew Baker

Department of Environmental Studies: Undergraduate Student Theses

The Amazon has been faced with extensive deforestation beginning in the 1960’s mainly for the purpose of cattle ranching and agriculture, as well as logging and mining making up smaller but noticeable portions. This rainforest is a place rich in its biodiversity of plants and animals, and until recently it was also one of the planet’s largest natural carbon sinks. This is important to help offset anthropogenic carbon emissions that are accelerating climate change, but because of the land use changes it has been subjected to, it has become another source of carbon release. This study aims to determine what …

State Of Utah Et Al. V Walsh Et Al., Ethan Halman Gonzalez

Department of Environmental Studies: Undergraduate Student Theses

To expand upon that, the State of Utah et al. wants to show the Department of Labor’s “Prudence and Loyalty in Selecting Plan Investments and Exercising Shareholder Rights” Rule proposed in December 2022, is arbitrary and capricious under the Administrative Procedure Act (APA) and Employment Retirement Income Security Act of 1974 (ERISA). The suit argues that the Department of Labor (DOL) oversteps the APA—as under the APA, the Court “shall… hold unlawful and set aside agency action, findings, and conclusions” that are “in excess of statutory jurisdiction, authority, or limitations,” or “arbitrary capricious, an abuse of discretion, or otherwise not …

Analyzing Sea Level Rise Adaptation And Mitigation Strategies In Louisiana And The Netherlands, Jonah Mcdowell

Department of Environmental Studies: Undergraduate Student Theses

Sea level rise is an increasingly dangerous threat. As a byproduct of climate change, this is an issue that has the potential to impact countless people, animals, and ecosystems across the globe. As sea level rise continues to worsen, it is imperative that coastal communities develop their own strategies and plans to combat this problem. This study focuses on two areas, the state of Louisiana and the country of the Netherlands, and studies how they have responded to this problem. These locations were chosen because sea level rise is proportionally more severe at these two locations compared to other areas …

Regenerative Agriculture: A Pathway For Addressing Nebraska’S Water Quality And Soil Degradation Challenges, Kjersten Hyberger

Department of Environmental Studies: Undergraduate Student Theses

It is important to begin this thesis by acknowledging that the State of Nebraska is on stolen Native land. Furthermore, the University of Nebraska is a land-grant university that was ultimately given 89,920 acres of Native lands for the paltry sum of $11,194. To date, the University of Nebraska has benefited from a 51:1 profit ratio on the funds raised from its 1873 land grant, raising over $500,000 in endowment principle. I humbly acknowledge that the privilege of earning my degree at UNL came through the often violent and bloody displacement of multiple tribal nations (High Country News, 2020).

Place-Based Pedagogies In Post-Secondary Science Education: A Scoping Literature Review, Megan Swain

Department of Environmental Studies: Undergraduate Student Theses

How do we connect students to a class and how do educational professionals create those connections? What makes an educational experience memorable? How do we cultivate students who are passionate and engaged? These are all important questions in educational fields and ones that have increasing importance in a world of growing virtual education. This thesis aims to look deeper into one method, place-based education that attempts to answer some of these questions.

Place-based education (PBE) is a pedagogy that utilizes the local physical environment and community as an educational tool. Educators focus lessons on places, people, and things surrounding their …

Energy Efficient Integrated Mems Neural Network For Simultaneous Sensing And Computing, Hamed Nikfarjam, Mohammad Megdadi, Mohammad Okour, Siavash Pourkamali, F. M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

Biological systems seamlessly combine multiple functions in lightweight and energy-efficient structures. Such capability in synthetic structures would be desirable in numerous engineering applications such as aerospace, robotics and wearable devices. Here we report an integrated silicon-based structure configured to sense, perform different classification algorithms, and produce an action signal within the same physical layer. The algorithms are coded in the mechanical responses of the sensing elements of multiple coupled micro-electromechanical systems (MEMS), simultaneously capturing acceleration measurements to produce an actuated signal. This all-in-one structure operates with zero circuitry and low power consumption. As a demonstration, we designed and fabricated a …

Theory Of Invariant Manifold And Foliation And Uniqueness Of Center Manifold Dynamics, Bo Deng

Department of Mathematics: Faculty Publications

Here we prove that the dynamics on any two center-manifolds of a fixed point of any C^k,1 dynamical system of finite dimension with k ≥ 1 are C^k-conjugate to each other. For pedagogical purpose, we also extend Perron’s method for differential equations to diffeomorphisms to construct the theory of invariant manifolds and invariant foliations at fixed points of dynamical systems of finite dimensions.

Exploration Of The Lived Experiences Of Native American Science Teachers Of The Great Plains: A Narrative Inquiry, Uma Ganesan

Department of Teaching, Learning, and Teacher Education: Theses and Other Student Research

The complicated history of the education of Native American children through U.S. government-sponsored practices has led to the elimination of the Native children’s sense of Indian identity, culture, and language (Noel, 2002). In addition, increased emphasis on standardization and high-stakes accountability under the No Child Left Behind Act of 2001 has resulted in less culturally responsive educational efforts and more Indigenous students left behind in school systems (Castagno & Brayboy, 2008). This has led to Indigenous students being underrepresented in science, technology, engineering, and mathematics (STEM) fields where they account for only 3% of STEM workers (Fry, Kennedy, & Funk, …

Exploring Stem Teaching Assistants’ Self-Efficacy And Its Relation To Approaches To Teaching, Cody R. Smith, Deepika Menon, Annette Wierzbicki, Jenny Dauer

Department of Teaching, Learning, and Teacher Education: Faculty Publications

Undergraduate and graduate teaching assistants (TAs) play large roles in introductory undergraduate education despite having little to no teaching experience or professional development (PD). Self-efficacy and teaching approach have each been studied as independent variables that impact teaching performance and student learning in the absence of practiced skill or developed knowledge. This study explored relationships between TAs’ teaching approaches and teaching self-efficacy. Self-efficacy was measured using the Graduate Teaching Self-Efficacy Scale (GTA-TSES), and teaching approach was measured using the Approaches to Teaching Inventory (ATI). The following research questions guided the study: What is the relationship between TAs’ approaches to teaching …

Career Interests, Sarah Stepanek, Megan Paul

Umbrella Summaries

Career interests reflect individuals’ “trait-like preferences for activities, environments, and outcomes that motivate goal strivings and achievement” (Jones et al., 2020). Simply put, interests are a series of likes and dislikes that develop alongside one’s cognitive abilities and personality to shape human behavior (Jones et al., 2020; Low et al., 2005). Interests, thus, drive the amount of time and effort individuals spend acquiring knowledge and abilities within a certain domain and their pursuit of educational and career goals (Jones et al., 2020). According to vocational choice theory, individuals tend to seek work that aligns with their interests, and when this …

The Influence Of The Substrate On The Functionality Of Spin Crossover Molecular Materials, Saeed Yazdani, Jared Phillips, Thilini K. Ekanayaka, Ruihua Cheng, Peter A. Dowben

Department of Physics and Astronomy: Faculty Publications

Spin crossover complexes are a route toward designing molecular devices with a facile readout due to the change in conductance that accompanies the change in spin state. Because substrate effects are important for any molecular device, there are increased efforts to characterize the influence of the substrate on the spin state transition. Several classes of spin crossover molecules deposited on different types of surface, including metallic and non-metallic substrates, are comprehensively reviewed here. While some non-metallic substrates like graphite seem to be promising from experimental measurements, theoretical and experimental studies indicate that 2D semiconductor surfaces will have minimum interaction with …

Classroom Social Support: A Multiple Phenomenological Case Study Of Mathematics Graduate Teaching Assistants’ Decision Making In The Classroom, Brittany Johnson

Department of Mathematics: Dissertations, Theses, and Student Research

Research suggests that support offered by an instructor can have a significant impact on the student experience, both in terms of classroom performance and affective well-being. Research also suggests that there are different types of support that instructors can offer (e.g., emotional support, instrumental support, informational support, and appraisal support). Although such research suggests that students perceive and are affected by these different types of support in different ways, there does not appear to be research surrounding the decision-making process behind instructors offering the support or the extent to which social support is a priority for them in the classroom. …

Stabilizing Polar Phases In Binary Metal Oxides By Hole Doping, Tengfei Cao, Guodong Ren, Ding-Fu Shao, Evgeny Y. Tsymbal, Rohan Mishra

Department of Physics and Astronomy: Faculty Publications

The recent observation of ferroelectricity in the metastable phases of binary metal oxides, such as HfO₂, ZrO₂, Hf_0.5Zr_0.5O₂, and Ga₂O₃, has garnered a lot of attention. These metastable ferroelectric phases are typically stabilized using epitaxial strain, alloying, or defect engineering. Here, we propose that hole doping plays a key role in the stabilization of polar phases in binary metal oxides. Using first-principles density-functional-theory calculations, we show that holes in these oxides mainly occupy one of the two oxygen sublattices. This hole localization, which is more pronounced …

Climate-Controlled Submarine Landslides On The Antarctic Continental Margin, Jenny A. Gales, Robert M. Mckay, Laura De Santis, Michele Rebesco, Jan Sverre Laberg, Amelia E. Shevenell, David M. Harwood, R. Mark Leckie, Denise K. Kulhanek, Maxine King, Molly Patterson, Renata G. Lucchi, Sookwan Kim, Sunghan Kim, Justin Dodd, Julia Seidenstein, Catherine Prunella, Giulia M. Ferrante, Iodp Expedition

Department of Earth and Atmospheric Sciences: Faculty Publications

Antarctica’s continental margins pose an unknown submarine landslidegenerated tsunami risk to Southern Hemisphere populations and infrastructure. Understanding the factors driving slope failure is essential to assessing future geohazards. Here, we present a multidisciplinary study of a major submarine landslide complex along the eastern Ross Sea continental slope (Antarctica) that identifies preconditioning factors and failure mechanisms. Weak layers, identified beneath three submarine landslides, consist of distinct packages of interbedded Miocene- to Pliocene-age diatom oozes and glaciomarine diamicts. The observed lithological differences, which arise from glacial to interglacial variations in biological productivity, ice proximity, and ocean circulation, caused changes in sediment deposition …