Digital Commons Network^™

Spatial Hearing In Simulated Reverberant Classroom Environments, Gabriel Seth Evan Weeldreyer

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

Spatial hearing provides access to auditory spatial cues that promote speech perception in noisy listening situations. However, reverberation degrades auditory spatial cues and limits listeners’ ability to utilize these cues for segregating target speech from competing babble. Hence, spatial unmasking—an intelligibility benefit from a spatial separation between a target and masker—is reduced in reverberant environments as compared to free field. This work tests the hypothesis that interaural decorrelation, the result of increasing reverberation, will broaden the perceived auditory source width with a cascading effect of reduced auditory spatial acuity and subsequently poorer spatial unmasking. To understand the perceptual consequences of …

Impact Of Plant Defenses And Aphid-Associated Microbes In Modulating Sorghum–Sugarcane Aphid Interactions, Edith Ikuze

Department of Entomology: Dissertations, Theses, and Student Research

Sorghum (Sorghum bicolor) is a vital cereal crop globally, facing challenges from invasive pests such as the sugarcane aphid (SCA; Melanaphis sacchari). To elucidate mechanisms of sorghum resistance to SCA, we examined the role of plant defenses and the influence of aphid-associated microbes in modulating sorghum defenses. Lignin is a complex heterogenous polymer present in nearly all plant cell walls that plays a critical role in protecting plants from various stresses. In this study, we investigated the role of the caffeoyl coenzyme-A O-methyltransferase (CCoAOMT), one of the core enzymes in monolignol biosynthesis pathway that leads to lignin …

First-Principles Studies Of Spin Transport And Spin-Orbit Torques, Giovanni Gabriel Báez Flores

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

This dissertation presents first-principles studies focusing on the effects of interfacial spin relaxation in metallic interfaces, interfacial intermixing on spin-orbit torques, and the effects of alloying on the transport properties of Fe|MgO|Fe magnetic tunnel junctions. Spin transport and spin-orbit torques are at the heart of phenomena in magnetic memory devices, such as tunnel magnetoresistance and magnetization switching. This work explores spin transport, spin-orbit coupling, spin-orbit torques, and tunneling magnetoresistance in a variety of materials and interfaces.

First discussed is the role of spin-orbit coupling at metallic interfaces by establishing a generalized magnetoelectronic circuit theory for normal metal (NM) interfaces, (NM|NM), …

Genome-Scale Metabolic Modeling Of Chitin-Degrading Microbial Systems, Aimee Kristin Kessell

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

As a major component of fungal cell walls and exoskeletons of invertebrates, chitin is widespread in soils, constituting the second most abundant biopolymer in nature. Composed of N-acetyl-D-glucosamine chains, it serves as a vital source of nutrients, including both carbon and nitrogen, for the growth of microorganisms. A solid understanding of the microbial degradation of chitin is critical for predicting their impacts on biogeochemical cycling in soil ecosystems. Organisms that degrade biopolymers (degraders) produce energetically expensive extracellular enzymes to break down complex organic carbons into simpler labile forms that are sharable with other species, including those that do not contribute …

An Annotated Bibliography Of 45 Select 21st-Century Electroacoustic Pieces For B-Flat Clarinet Suitable For The Undergraduate Clarinetist, Emily Jean Rose

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

Electroacoustic literature for the clarinet is bountiful and accessible, though many students do not experience working with this genre until they become a graduate student, if even then. Utilizing a detailed rubric, each of these 45 works in this document are graded according to their accessibility, techniques explored, and overall difficulty to approach to better serve the educator and assist the undergraduate clarinetist in performing this genre of repertoire.

With the accessibility of electronics and electronic equipment coming more readily available to composers and performers at the start of the 21st-century, electroacoustic literature found a sense of deliverance in the …

Effect Of Biomass Water Dynamics In Cosmic-Ray Neutron Sensor Observations: A Long-Term Analysis Of Maize–Soybean Rotation In Nebraska, Tanessa Morris

School of Natural Resources: Dissertations, Theses, and Student Research

The precise measurement of soil water content (SWC) is crucial for effective water resource management. This study utilizes the Cosmic Ray Neutron Sensor (CRNS) for area-averaged SWC measurements, emphasizing the need to consider all hydrogen sources, including the time-variable ones like plant biomass and water content. Chapter 1 presents a background on soil moisture estimation, CRNS technology, and an overview of the study. It discusses various soil moisture measurement techniques, highlights the gap in knowledge addressed by CRNS technology, explains CRNS functionality and advancements, and outlines the study's motivations and methods.

Chapter 2 reports a study conducted near Mead, Nebraska, …

Clothing, From Textiles To Pixels: Exploring The Possibilities Of Design With Clo3d Software, Tina Shetabi

Department of Textiles, Merchandising and Fashion Design: Dissertations, Theses, and Student Research

This project explores the application of Clo3d software as a transformative educational tool in couture fashion design instruction. Despite couture's rich tradition of meticulous craftsmanship and personalized design, its teaching methodologies have yet to fully leverage digital advancements. This project examines the integration of Clo3d into the apparel design program curriculum, specifically focusing on the undergraduate course Digital Apparel Design at the University of Nebraska Lincoln. Through a combination of theoretical knowledge and practical application, this project aims to determine how digital tools like Clo3d can enhance the learning outcomes of fashion design students by providing a more interactive and …

Predicting The Future Of Myanmar’S Civil War: Can Half A Century Of Military Rule Be Defeated?, Nathan Ritterling

Honors Program: Senior Projects (Public)

In 2021, the military of Myanmar launched a coup in response to their overwhelming defeat in the 2020 elections, resulting in an end to the country’s tentative move towards democracy and in intense violence to suppress opposition to the coup. Anti-junta forces quickly formed in the aftermath to directly oppose the military and return the country to democratic rule, and began collaborating with long-standing ethnic militias in their efforts. This has led to a state of prolonged civil war, as the two sides fight for dominance over the nature of Myanmar’s future government. This paper investigated the potential outcome of …

Topgolf Callaway Brands, Corp. Strategic Analysis, Sean Smith

Honors Program: Senior Projects (Public)

Topgolf Callaway Brands, Corp. (the “Company”, “Topgolf Callaway”, “Topgolf”, or “Callaway”) is an industry-leading golf and active lifestyle company that provides golf entertainment experiences, designs and manufactures premium golf equipment, and sells golf and active lifestyle apparel and other accessories through their family of brand names. They operate under the Topgolf, Callaway, Jack Wolfskin, OGIO, TravisMathew, Odyssey and Toptracer logos for their various product and service offerings. This report seeks to understand the industries in which the firm operates, the forces present in those industries, the resources and advantages of the firm, risks associated with their operations, and recommends several …

Mechanical Engineering Capstone: A Reflection On The Design And Prototyping Of A Portable Water Heating System, Timothy Goldsmith

Honors Program: Senior Projects (Public)

This thesis includes several documents from a Mechanical Engineering Capstone course. These include project postmortem reports written at the conclusion of each term. These reports summarize the designing and prototyping of a portable water heating system. Additionally, this thesis includes written feedback on the final presentations for six other senior design teams. In these documents, presentations and projects are evaluated and encouragement and feedback are provided for the teams. The final component of this thesis is an essay reflecting on the different leadership roles assumed during the capstone course.

Coarse-Work: An Investigation Into The Impact Of Materiality In The Interior Educational Setting, Isabel G. Robb

Honors Program: Senior Projects (Public)

Education design in modern suburban America curates learning environments that are cold and impersonal, being used more as a place to keep youth during the day than as a place where they can truly learn about and understand the world around them. This learning environment does not suit all students, especially those with learning disabilities, and it leaves little room for flexibility in classroom usage.

Focusing on creating a learning environment where all students feel welcome and are able to effectively learn, this projective design research project aims to provide a comprehensive intervention through the built environment and interior design, …

Orms And Database Design, Kalim Dumas

Honors Program: Senior Projects (Public)

This thesis explores the relationship between database design and Object-Relational Mapping (ORM) design, investigating how they have evolved together and influenced each other. It addresses a theoretical discussion, a practical implementation, and some observations regarding integrating an ORM into my Senior Design project. My Senior Design project was originally built without the intention of implementing an ORM.

There are a lot of complicated discrepancies between Relational Databases (RDBs) and Object-Oriented Programming Languages (OOPLs), called the Impedance Mismatch Problem. The fact that they are both foundational pillars in software engineering means that one cannot simply change to match the other. ORMs …

Evaluating Oer Resources As An Inclusive Teaching Practice, Hannah Ray

Honors Program: Senior Projects (Public)

Open Educational Resources (OER) have become a popular alternative to traditional textbooks for university students throughout the U.S. due to their affordability and positive educational outcomes. To better determine the outcomes of OER usage, this study evaluates the implementation of OER at an individual course level and across courses at the University of Nebraska-Lincoln (UNL). Student success was measured by the DFW rates, which refers to the number of students who received a grade letter of D, failed, or withdrew from the course, before and after the implementation of OER resources in various courses. At the individual course level, students’ …

T-Mobile Strategic Audit, Naren Narasimhan, Kathryn Kraemer, Alex Nydahl, Carlos Fuentes, Cole Swofford

Honors Program: Senior Projects (Public)

This strategic audit delves into the performance and competitive landscape of T-Mobile within the wireless communications industry. The research question driving this study was to assess T-Mobile's position and prospects across various facets of its business operations. The research methodology was gathered from T-Mobile's official sources such as its website, annual reports, press releases, and other publicly available information. The audit offers a comprehensive examination of T-Mobile's strategic landscape, encompassing industry dynamics, the company's mission, and its overarching objectives. It proceeds with an extensive external and internal analysis, culminating in insights into T-Mobile's competitive advantage and future positioning vis-à-vis other …

First Solar Strategic Audit, Sydney Pelster, Abigail Cota, Katherine Schoenfelder, Nolan Mauk, Eli Waring

Honors Program: Senior Projects (Public)

This case study explores First Solar, a global leader in the photovoltaic solar module industry. Using strategic management strategies and principles, we have curated a strategic audit to analyze the company’s competitive position. We used First Solar’s publications and website as well as general articles on the solar industry, analyst findings, and additional public findings as the basis of our analysis. Overall, our goal was to apply the learned strategic management concepts to a complex organization and identify First Solar’s potential competitive advantages.

We looked at many factors for First Solar, including firm analysis, industry analysis, external analysis, internal analysis, …

Determining The Impacts Of Corn Silage Mixing Ratios On Hydrogen Production From Beef Cattle Manure, Katya Faber-Quimby

Honors Program: Senior Projects (Public)

With global warming becoming an increasingly serious threat and a growing population requiring additional energy resources, interest in the production of clean energy from the agricultural sector has surged in popularity. Biohydrogen, also known as green hydrogen, is H₂ that has been produced using renewable energy, such as from agricultural byproducts or waste materials. It presents a promising alternative to nonrenewable resources due to its high potential for energy storage and lack of carbon emissions when used. Cattle manure has been explored as a resource for the production of biohydrogen. Selecting for hydrogen-producing microbes in the manure serves the …

Modeling Pedestrian And Bicyclist Crash Exposure With Location-Based Service Data, Yunwoo Nam, Jason Hawkins, Don Butler, Nicholas Aldridge, Mohammad Elayan, Kwant Il (Jason) Yoo

Nebraska Department of Transportation: Research Reports

The rising popularity of non-motorized transportation has brought about safety risks. The inclusion of accurate traffic volume information is one of the key elements to produce robust outcomes when researching safety. The project investigates and enhances transportation safety for pedestrians and bicyclists, emphasizing the integration of Location-Based Services (LBS) data, particularly StreetLight data, to analyze traffic volume and associated risks. The calibration process demonstrates the significance of traffic volume as a key variable influencing prediction accuracy across pedestrian, bicyclist, and vehicle models. The crash analysis reveals a strong correlation between crash counts and traffic activity, with noteworthy findings emerging at …

Ecological Dynamics Of Cenozoic North American Mammals, Alexandria Brandis Shupinski

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

Understanding how community structure is affected by various ecological, climatic, and environmental changes is a long-standing goal in ecology. However, disentangling human impacts from these other variables is difficult when using short modern timescales and anthropogenically altered communities. The fossil record provides a means to investigate community structure dynamics across critical intervals, excluding humans as a variable. Here, in three studies, I assess changes in North American mammal paleocommunity structure across the last 66 million years (Ma) at multiple temporal and spatial scales. In Chapter 1, I identify changes in mammal functional diversity (FD) locally and continentally, using three independent …

Lockheed Martin Strategic Audit, Trevor Deboer, Gunnar Lombard, Sam Nelson, Tj Taylor, Paul Wynegar

Honors Program: Senior Projects (Public)

Abstract

This case study explores Lockheed Martin, a global leader in defense contracting. Our team performed a strategic audit using the theories of strategic management. Our research was pulled from various sources, including Lockheed Martin’s website, SEC filings, related news articles, and relevant industry analysis. The goals of this case study revolved around collecting data and performing analysis to evaluate Lockheed Martin’s potential for competitive advantage in the airplane and parts manufacturing industry.

Some of the various analyses performed on Lockheed Martin include firm analysis, industry analysis, internal analysis, external analysis, competitive dynamics, business-level strategy, corporate-level strategy, and exploring their …

Olympic Infrastructure: The Effect On Host Cities, Abriana Wilson

Honors Program: Senior Projects (Public)

Hosting the Olympic Games is an event associated with promoting urban development, economic surplus, and enhanced global visibility. However, the development of the Olympic Games is a topic that curates debate and scrutiny. This thesis aims to thoroughly analyze the different effects of Olympic Infrastructure on host cities. This study investigates both short- and long-term effects of large-scale Olympic development through real-world analysis, and qualitative, and quantitative data. Key areas of focus include legacy building, environmental awareness, health and safety, displacement, and sustainability. This research seeks to evaluate past Olympic Games to provide host cities with the information to create …

Spotify: A Strategic Analysis Of A Digital Music Streaming Industry Leader, Madison Giacomo

Honors Program: Senior Projects (Public)

Spotify (Spotify Technology S.A) is a digital music streaming platform headquartered in Stockholm, Sweden. Offering music, podcasts, and audiobooks, Spotify is the leading digital music streaming platform with over 30% of the market share. Spotify bases their business model on user growth and experience, content acquisition and expansion, monetization, and partnerships and collaborations. Spotify’s main focus is to differentiate themselves through a personalized user experience, offering music and podcast recommendations based on listening history. This analysis looks to understand Spotify’s growth and business strategy within a competitive industry, through the use of a PESTEL analysis, Porter’s Five Forces Analysis, evaluating …

Mapping Stratcom: The Architecture Of Offutt, The U.S. Military, And Strategic Command, Anna Miles

Honors Program: Senior Projects (Public)

Architecture and the military have always been intertwined. The built environment both on and off U.S. military installations responds to the events, history, and influences of the military. This project explores one example of this by investigating the history of the United States Strategic Command (USSTRATCOM), headquartered at Offutt Air Force Base in Nebraska, through the lens of architecture.

When exploring USSTRATCOM, this project aims to understand not only its history, but also its impact: on Offutt, on the world, and most importantly, on architecture. Firstly, the project explores the history of the military in the state of Nebraska and …

Design And Fabrication Of A Carbon Fiber Wheel For The Husker Motorsports Club, Benjamin Bashtovoi, Jordan Chapin, Michael Pineda, Caden Lind, Thomas Crum

Honors Program: Senior Projects (Public)

Every year, the Husker Motorsports team participates in a Formula SAE competition that challenges students to design and manufacture a Formula-style vehicle to compete against colleges from around the world. The Husker Motorsports club has sponsored this senior capstone project to improve the vehicle’s performance by reducing unsprung mass. Unsprung mass reduction has numerous benefits on vehicle dynamics, including improved acceleration, handling, and braking. To achieve these performance improvements, the team developed carbon-fiber composite wheels that weigh less than the current wheel solution and provide better rigidity. The team designed and modeled the wheel according to the 2023-2024 competition car …

Drag Reduction In Channel Flow Configurations For Laminar And Turbulent Flow Past Superhydrophobic Surfaces, Henry Louis Ems

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

In this work, we present friction drag reduction in minichannel laminar flow past superhydrophobic metallic surfaces. Femtosecond laser surface processing (FLSP), a one-step scalable method, was used to create permanent microscale and nanoscale structures on 316 stainless steel plates. The resulting superhydrophilic plates were covered by tall (215 μm) or short (27 μm) structures. The FLSP plates were then transitioned to superhydrophobic by evaporative deposition of a fluorinated silane, a low surface energy coating. Using purified water, the friction factor was obtained by measuring pressure drop along a minichannel with a rectangular cross section for flow rates corresponding …

Irt-Based Irrigation Scheduling And Dry Bean Crop Water Productivity Under Different Irrigation Scenarios In The Nebraska High Plains, Angie Gradiz

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Irrigation plays a critical role for crop production in western Nebraska of the United States, where crop evapotranspiration often exceeds in-season precipitation. This study investigated the impacts of different irrigation treatments on yield and key physiological parameters of dry edible beans grown in semi-arid western Nebraska during the 2022-2023 growing seasons. Seven irrigation levels (0%, 25%, 50%, 75%, 100%, 125%, 150%) of the fully irrigated treatment (FIT), were applied using a Variable Rate Irrigation (VRI) Linear-Move Sprinkler System. Additionally, an eighth treatment was scheduled based on measurement from infrared radiometry thermometers (IRT) to evaluate the performance of the two-source energy …

Toxicological Effects And Treatment Of Accidental Ingestion Of Simparica Trio® In Felis Catus: An Investigative Review, Aussia M. Stander

Honors Program: Senior Projects (Public)

Simparica TRIO^®, a canine endectocide manufactured by Zoetis, contains sarolaner, moxidectin, and pyrantel pamoate salt in an orally administered chewable tablet. These compounds are all toxic to both cats and dogs in sufficient amounts. As Simparica TRIO^® rises in popularity among pet owners, Felis catus (felines, cats) in multi-pet households (households with both cats and dogs) are at increased risk of overdosage and toxicosis from accidental ingestion of Simparica TRIO^® due to their smaller weight.

Simparica TRIO^® is not for feline use and little literature exists on the symptoms of and treatment for accidental ingestion …

Consequences Of The Megafauna Extinction: Changes In Food Web Networks On The Edwards Plateau Across The Pleistocene–Holocene Transition, Quentin A. Smith Jr.

School of Biological Sciences: Dissertations, Theses, and Student Research

We are experiencing biodiversity loss due to climate change and human impacts, which is not only harmful to the environment but can also alter the composition of communities and interactions among species. The late Pleistocene experienced a loss of large-bodied mammals which resulted in significant changes in community structure due to changes in body size, diet, and species associations. The impact of these changes on species interactions and community structure across the Pleistocene-Holocene transition remains poorly understood. Using a robust data set of species composition, stable isotopes, body size, and climate variables, we constructed and compared ecological networks of mammal …

Impact Of Strategic Postweaning Supplementation On March- And May-Born Yearling Range Heifer And Calf Growth And Performance In The Nebraska Sandhills, Josie Nicole Crouch

Department of Animal Science: Dissertations, Theses, and Student Research

Three experiments were conducted at the Gudmundsen Sandhills laboratory near Whitman, Nebraska. Experiment 1, a retrospective regression analysis, evaluated the impact of heifer percentage of mature body weight (BW) at breeding on heifer performance, subsequent pregnancy rates, and calf production. Overall pregnancy rates were greater (P < 0.01) for heifers at 60 to 70% of mature BW than 50 to 55%, with no differences in pregnancy rates (P ≥ 0.15) after 2-years of age. Heifers at 50 to 60% of mature BW had a greater (P = 0.05) proportion give birth in the first 21-d. A higher percentage of mature BW at breeding resulted in greater (P < 0.01) BW at birth and weaning for offspring.

Experiments 2 and 3 were 3-year studies that evaluated the impact …

Implementation And Effectiveness Of Stress Management Strategies Among Stem Students At The University Of Nebraska-Lincoln, Dylan Hiser

Honors Program: Senior Projects (Public)

High-stakes exams often induce significant stress among STEM (Science, Technology, Engineering, and Math) students, impacting their academic performance and overall well-being. As the opportunity for careers in STEM grows rapidly, understanding the stressors that students face remains critical in mitigating the effects of this stress and ensuring the success of these students. The objective of this study is to determine how well STEM students respond to recommended interventions that mitigate exam stress and to identify trends in these students’ exam scores. To accomplish this, a set of surveys was sent to undergraduate STEM students at the University of Nebraska-Lincoln. The …

Final Design Of Legion Hall Revitalization In Potter, Nebraska, Madison Brennfoerder

Honors Program: Senior Projects (Public)

This project was conducted to renovate and revitalize the Legion Hall community center in the Village of Potter located in western Nebraska north of the Interstate. The work completed for this project can be separated into five disciplines: Hydrologic & Hydraulic Design, Geotechnical Analysis, Structural Analysis, Environmental Analysis, and Transportation Design. Legion Hall is a historical building within The Village of Potter which was built in 1917. The Village of Potter has recently acquired the rights to the hall and is seeking to revitalize the historical community center to increase tourism in the village.