Physical Sciences and Mathematics Commons^™

Global, Continental, And Local Scale Paleoenvironmental Reconstruction Methods For Interpreting The History Of Miocene North America And The Great Plains, Willow Hue Nguy

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

The Miocene of North America is characterized by dynamic changes in herbivore communities, habitat composition, and global climate. Long-term cooling and drying trends influenced large changes in floral and faunal communities. The Great Plains, North America shifted from closed-canopy biomes to open-canopy biomes with C3-grasses to biomes with C4-grasses. This shift affected the herbivore communities as browsing-adapted ungulates were replaced by grazing-adapted ungulates. Much focus has centered on the Great Plains, so it is not well understood how the changes in biomes compare to other regions of North America. The models used for vegetation density indicate open-canopy biomes since at …

Investigating Programming Behaviors To Understand Student Engagement And Experience In Introductory Programming Courses, Marcus Eugene Gubanyi

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

Introductory programming courses are foundational to developing students’ problem-solving abilities and shaping their persistence in computing pathways. Engagement with programming tasks plays a central role in student learning and experience. Many research measures, including self-reports and code submissions, offer only a limited view of student engagement with programming tasks. This dissertation leverages programming process data, consisting of keystrokes and compilation events, to capture the programming process as it unfolds and to investigate observable programming behaviors. Guided by educational theories, three studies examine how students’ programming behaviors vary across instructional and assessment contexts, how they relate to motivational profiles, and how …

Large-Scale Experimental Study On The Impact Of Air Cleaning & Ventilation On Indoor Air Quality And Student Illness-Related Absenteeism, Daud Nosham

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

This large-scale randomized experimental field study investigated the effect of portable air purifiers (PAPs) on classroom’s air quality and student’s illness related absenteeism. PAPs were installed in 317 classrooms from various school districts located in Eastern Nebraska. The classrooms were randomly assigned into four conditions: three treatment conditions (T1, T2 & T3) and one control condition (device without any filter). T1 was equipped with HEPA filters, T2 added Activated Carbon (AC) layer to HEPA, and T3 further integrated Germicidal Ultraviolet (GUV) alongside HEPA and AC filters. The measured variables were carbon dioxide (CO2), fine particles (PN2.5) and coarse particles (PNcoarse), …

An Integrated Modeling Framework To Evaluate Circularity Of The Corn–Water–Ethanol–Beef Nexus, Heydi Han

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

This dissertation examines the transition from conventional linear agricultural and food bioenergy systems toward more circular, resilient, and resource-efficient configurations. Prior research indicates that spatial and temporal variability in soil, weather, animal biological responses, and management decisions strongly influences productivity, nutrient-use efficiency, and profitability. Studies have also shown that a diversified circular system can buffer these sources of variability, improving stability and adaptive capacity. Building on these insights, the central focus of this work is to develop an integrated modeling framework to evaluate circularity within the Corn-Water-Ethanol-Beef (CWEB) nexus and explore how climate variability and management choices shape system-wide performance. …

Making Deep Neural Networks Trustworthy: Intelligibility And Safety Through Symbolic Methods, Eleanor Catherine Quint

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

The rapid adoption of deep learning has come at the cost of properties long valued in artificial intelligence: intelligibility and safety. This dissertation develops methods that restore these properties by coupling neural networks with symbolic structure.

First, for supervised classification, I propose a differentiable decision tree integrated with a supervised variational autoencoder. The resulting model maintains competitive accuracy and generative performance while exposing clear macro-features in its latent space, improving interpretability.

Second, for reinforcement learning, I extend constrained Markov decision processes by specifying constraints in formal languages. This formal language constrained MDP enables the use of automata for state augmentation, …

Stable Isotope Paleoecology In The Bridgerian (Early Eocene): Investigation Of The Bridgerian Crash And The Canopy Effect, Aaron M. English

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Early Eocene Climatic Optimum (EECO) was the warmest sustained interval of the Cenozoic. Its waning stages coincided with a marked decline in mammalian biodiversity known as the Bridgerian Crash, which was likely driven by increasingly cooler and drier conditions. Paleobotanical evidence suggests the early Eocene supported wet, subtropical to tropical forests at mid-latitudes, however the structure of these forests at the close of the EECO remains poorly understood. In this study, I measure carbon isotope values (d¹³C_E) from the enamel of early Bridgerian (~52.2 – 48.3 Ma) herbivorous mammals from the Greater Green River …

How Eppley Airfield Could Be Reducing Your Power Bill (But They’Re Not), Cherry Pham

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Eppley Airfield in Nebraska is spending $950 million on their renovation and services are still running, even during construction. Part of the airport’s renovation budget could be allotted to installing solar canopies. In the long run, airports with solar canopies reduces their own electricity expenses.

Carbon Markets: A New Opportunity For Farmers, Emma Wrede

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Farmers have always known that healthy soil is their greatest asset to their success. Carbon markets are simply finding a new way to identify, measure, and compensate that value in a new way. In a time where every dollar counts, carbon credit markets can strengthen farmers’ margins and enhance their land health which they depend on. With continued research, improved regulation, and clearer guidelines, this system will work for both farmers and the environment.

Nebraska's Hidden Goldmine: Wind Power On Farms, Adelaide Witte

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Nebraska’s been hesitant to go all in on wind energy. People often worry about things like noise, how turbines look, or even potential impacts on human health. Community concerns are valid and should always be acknowledged. However, addressing them doesn’t require putting all development on hold.

“The Good Life” Of Ai, Lauren Smith

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Artificial Intelligence, or AI, is powered by data centers, sprawling warehouses of servers that require massive amounts of electricity and water to operate. The United Statesalready has more than 1,000 data centers, with nearly 400 more on the way.

Nebraska is next. Google is building a major new data center in North Lincoln, adding to the 18 operating across the state.

Our collective use of tools like ChatGPT, Google’s Gemini and Microsoft’s Copilot has fueled a boom in generative AI, and with it a surge in energy and water consumption.

The need for AI regulation isn’t a future concern. It’s …

The Land Competition Between Crops And Solar: Why Nebraska Farmers May Not Have To Choose, Jada Vogel

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

There are significant benefits that can come from implementing agrivoltaics on farms in Nebraska. The economic gains from the use of agrivoltaics alone may be sufficient to get individuals to pursue their use.

The Myth Of Clean Manufacturing, Andrea Phan

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

We must act now and reform renewable energy credits to reflect real progress. This means tightening Scope 2 rules so that renewable claims are tied to additional, time and location matched, clean power. It means rewarding measurable integration, so that real emissions are avoided, not waived by retroactive certificates. RECs can still play a role, but only in a system that demands we use the tools we already have.

Nebraska’S Best Option: Carbon Capture, Leah Bates

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Some may argue that carbon capture technologies are not optimal due to their high costs or how they take focus away from implementing renewable energy sources. However, carbon capture and storage technologies are currently the best options in reducing carbon emission and Nebraska is leading the way.

Water Current, Volume 57, No. 3, Fall 2025

Water Current Newsletter

No abstract provided.

Learn To Fly: Enabling Deep Learning Based Perception And Control In Aerial Robotics, Krishna Muvva

School of Computing: Dissertations, Theses, and Student Research

Uncrewed Aerial Vehicles (UAVs) are increasingly deployed in dynamic, GPS degraded, and cluttered environments, yet their autonomy remains fundamentally constrained by limitations in onboard perception and real-time control. This dissertation addresses these challenges by proposing a unified framework that co-designs deep learning-based perception and model-based control, organized around three core thrusts: Learn to Track, Learn to Localize, and Learn to Evade.

Learn to Track develops dynamic and adaptive perception control mechanisms that optimize CNN inference for target tracking. A control-aware CNN framework dynamically adjusts inference frequency based on UAV motion, reducing latency while maintaining visual lock. An adaptive CNN with …

A Better Great Plains: Bridging The Implementation Gap For A Better Future, David W. Sandahl

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

The Northern Great Plains is experiencing extensive native grassland loss and landscape degradation, jeopardizing both ecological integrity and the socio-economic systems that rely upon these ecosystems. In an early effort to lessen degradation, the United States Department of Agriculture (USDA) introduced the Conservation Reserve Program (CRP) which generated ecosystem services benefits such as reduced soil erosion, improved water quality, and increased species diversity through the retirement of cropland and rangeland for 10- or 15-year contracts. However, CRP has not fully modernized alongside today’s agriculturalists and adoption remains shaped by an historically fraught socio-political context characterized by deep-seated mistrust between ranchers, …

Use Of Modified Z-Domain Peptides To Specifically Label The Constant Region Of Immunoglobulin G And Vegf, Madeline Allen

Department of Chemistry: Dissertations, Theses, and Student Research

Antibodies are increasingly being used in medicinal therapies due to their ability to specifically bind to a target antigen. This fundamental behavior of antibodies has been used as a key component in drug development to address common problems with traditional drug molecules such as off-targeting, fast drug clearance, and low efficacy. This thesis provides some background into how antibodies can be used as potential treatments for a few diseases. Chapter 1 begins with an overview of the human immune system, and the role antibodies play within it. Then, the variety of ways in which antibodies can be used as medicinal …

Understanding And Assessing Climate Change: Preparing For Nebraska’S Future, 2024 Climate Change Impact Assessment Report, Deborah J. Bathke, Eric Hunt, Heather Akin, Andrea D. Basche, Jesse E. Bell, Daniel R. Dileo, Ross Dixon, Martha Durr, Tonya Haigh, Francis John Hay, Kristina W. Kintziger, Nicholas A. Mcmillan, Hank Miller, Jerome Okojokwu-Idu, Crystal Powers, Tirthankar Roy, Zhenghong Tang, W. Ryan Wishart, Aaron R. Young, Sarah A. Sonsthagen, Jonathan J. Spurgeon

School of Natural Resources: Faculty Publications

Contents

Report Team

Acknowledgments

Executive Summary

Introduction

Climate Change Contexts: Global, National, and State

Observed Changes in Nebraska's Climate

Projections of Nebraska's Future Climate

Water Systems

Energy

Ecosystems

Agriculture

Human Health

Communities and the Built Environment

Indigenous Peoples

Climate Justice and Equity

The Response of Faith Communities

Nebraskans' Perceptions of Climate Change

Next Steps and Future Work

Supplemental Report: Adaptation, Risks, and Impacts

About the Authors

Faith-based Communities Survey

Evaluated Plans and Assessments

References

Futurescape Libraries Ai Toolkit, Keith Webster

Copyright, Fair Use, Scholarly Communication, etc.

A toolkit developed to explore scenario-specific strategies and activities that research libraries can undertake to prepare for various possible AI-influenced futures. The toolkit integrates the ARL/CNI AI Scenarios published in spring 2024 along with priorities trialed and refined by strategic thinkers working directly in, or adjacent to, the research library field during a Strategic Implications forum held December 7–8, 2024, in Washington, DC.

An Economic Assessment Of Precision Conservation With On-Farm Precision Experiment Data, Karina A. Schoengold, Badri Khanal, Taro Mieno, David S. Bullock

Cornhusker Economics

Using a novel dataset that includes within field variation in productivity, we find that partial field retirement for a prairie strip can not only provide conservation benefits, but can also be economically beneficial. We note that these results are for a single field with one year of data, and that additional years of production and fields are essential to determine how much these results can be generalized. We also note that precision systems can be costly, and a comparison of outcomes with and without this information is essential to determine if investing in such systems is profitable. However, variable rate …

Mapping Sedimentary And Crustal Thicknesses In The Northern Atlantic Ocean From Public Domain Geophysical Data, Hermione Lofton

College of Arts and Sciences: Undergraduate Theses and Other Student Projects

The Northern Atlantic Ocean is a complex region that contains many inactive and active tectonic features. These features include the Jan Mayen Microcontinent, Jan Mayen Fracture Zone, Aegir Ridge, Kolbeinsey Ridge, the Greenland-Iceland-Faroe Ridge, the Voring Plateau, the Voring Spur, and the Iceland Hotspot. This project is motivated by the region’s complex geology and its highly debated tectonic history and disputed crustal affinity. This study aims to evaluate tectonic elements of the Northern Atlantic Ocean with three major objectives. The first objective is to develop a map of crustal thickness from publicly available seismic refraction data. For the second objective, …

Drift Dynamics Of Early Life-Stage Invasive Carps, Saurav Karki

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

Asian carp species pose significant ecological threats to North American freshwater systems due to their invasive nature and prolific reproduction. Their semi buoyant eggs develop while drifting downstream with the river current. Understanding early life-stage transport is therefore critical for predicting recruitment potential and guiding management efforts. Existing fluvial egg drift models, including those relying on 1-D hydraulics and fully 3-D CFD-based models, are either inadequate for complex braided rivers or too computationally demanding for large-scale application. The Platte River in Nebraska, characterized by wide, shallow, multi-threaded channels, is dominated by two-dimensional flow conditions, making a depth-averaged 2-D modeling approach …

Traffic Prediction For Research And Education Networks: Anomaly-Aware Deep Learning And Benchmarking, Mohammad Arafath Uddin Shariff

School of Computing: Dissertations, Theses, and Student Research

Research and Education Networks (RENs) and High-Performance Computing (HPC) environments are critical infrastructures for modern scientific discovery, demanding sustained high-throughput and low-latency data transfers. Unlike commercial networks, RENs exhibit unique traffic characteristics, including predominant “elephant flows,” inherent burstiness, and complex temporal-spatial dynamics often decoupled from human-driven cycles. Traditional traffic forecasting methods, tailored for commercial Wide Area Networks (WANs), consistently fail to capture these distinct REN dynamics, leading to inefficient resource management and potential impediments to scientific progress.

This thesis addresses this critical gap by developing and validating a robust, scalable, and anomaly-aware traffic forecasting framework specifically tailored for REN/HPC networks. …

A Multi-Isotope Investigation Of Mammoth Diet, Habitat, And Movement Patterns In The Central Great Plains, U.S.A., Jacob Mccloskey

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

During the Last Glacial Maximum (LGM), the Great Plains in Nebraska consisted of wooded parklands and grasslands, whereas spruce (Picea) forests, parklands, and steppe grasslands dominated east of the Missouri River. I analyzed bulk carbon (δ¹³C), oxygen (δ¹⁸O), and strontium (⁸⁷Sr/⁸⁶Sr) isotopes from tooth enamel in isolated mammoth (Mammuthus) molars to compare diet and movement patterns in two late Pleistocene assemblages: one in Nebraska (n = 24), and one in western Iowa and Missouri (n = 17). Furthermore, I identified a morphometric subset of molars as …

Low-Level Polarimetric Signatures Of Supercells During Ef3+ Tornado Production, Anthony Noah Began

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Most EF3+ tornadoes are produced by supercells. Understanding of microscale features surrounding intense tornado production remains limited. This research aims to determine commonalities in low-level microphysical processes during intense tornado production via polarimetric radar signature assessment with a Python-based algorithm. Polarimetric variables hypothesized to reflect low-level wind profiles such as the differential reflectivity (Z_DR) arc and the Z_DR–K_DP (specific differential phase) separation vector will be investigated. Supercells which produced EF3+ tornadoes will be examined since these tornadoes pose the highest threat. From 2010 to 2024, the United States recorded approximately 19,100 tornadoes which resulted in …

Evaluation Of Performance Characteristics And Groundwater Contamination Risks Associated With On-Farm Swine Carcass Disposal Via Composting And Shallow Burial With Carbon, Gustavo Castro Garcia

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

This dissertation evaluates the performance of three on-farm swine carcass disposal methods: whole carcass composting (WCC), ground carcass composting (GCC), and shallow burial with carbon (SBC), focusing on biosecurity factors and groundwater contamination risks. Foreign animal diseases (FADs), such as African swine fever and classical swine fever, pose severe economic and animal well-being risks if introduced to the United States. With confirmation of an FAD, swine movement will be halted, creating an urgent need for practical, biosecure, and environmentally responsible on-farm disposal strategies for swine carcasses. Nebraska, as a leading swine-producing state, exemplifies the vulnerability of high-density livestock regions to …

Online Prediction Of Streaming Data, Aleena Chanda

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

We present two new approaches for point prediction with streaming data based on a) the Count-Min sketch and b) Gaussian Process Priors with random bias. The methods are intended for the most general case where no true model can be usefully formulated for the data stream. In statistical contexts, this is often called the M open problem class. For the Count Min Sketch method we show that the predicted distribution function ^F converges to F under the assumption that the data consists of i.i.d samples from a fixed distribution function F. To implement the Gaussian Process Prior methods, we used …

Reductive And Nucleophilic Cleavage Of Peroxides And Synthesis Of Tocotrienols As Radioprotective Targets, Amber Marie Schuster

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

I. SET CLEAVAGE OF PEROXIDES: INFLUENCE OF REDUCTANT AND PEROXIDE ON THE RATE AND MODE OF ALKOXY RADICAL FORMATION

The reductive cleavage of organic peroxides to generate alkoxy radicals is frequently accomplished via single-electron transfer (SET) from a reductant. Previous reports employ either symmetrical peroxides or peroxides with predictable cleavage behavior, such as peresters. We were interested in how the structure of the peroxide and the nature of the reducing system combine to impact the rate of reaction and the selectivity for alkoxy radical formation during cleavage of unsymmetric peroxides. In this dissertation, one will find the reactions of a …

How Developers Use Type-System Related Programming Language Features, Samuel W. Flint

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

Optional type annotations are a popular feature of programming languages that allow developers to omit explicit type information in code while, in some cases, retaining many of the benefits of static typing, such as in-code documentation, improved detection of type errors, or enforcement of code properties. However, how developers use and understand optional type annotations is not clear. The focus of this dissertation is to understand the use and comprehension of optional type annotations.

Optional type annotations are examined through four lenses: first, by examining the evolution of usage in a statically typed programming language (Kotlin, the default language for …

Resilience Of Interdependent Transportation And Healthcare Systems: A Simulation-Driven Framework Incorporating Social Equity And Facility Optimization, S. Yasaman Ahmadi

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

The overarching goal of this dissertation is to develop an integrated, simulation-driven framework to assess and enhance the resilience of interdependent transportation and healthcare systems before, during, and after natural hazards. By examining how spatial disruptions, social vulnerability, operational constraints, and infrastructure interdependencies affect access to and functionality of hospitals, this research offers a multifaceted evaluation of system performance under stress. This dissertation examines the impact of natural hazards, particularly floods, on the interdependent transportation and healthcare systems. The proposed approach combines and advances GIS-based network analysis, graph-theoretical modeling, and discrete-event simulation to evaluate system performance under different scenarios. The …