Digital Commons Network^™

The Impact Of Community On Professional Identity In Computer Science Education, Ian A. Kollipara

School of Computing: Dissertations, Theses, and Student Research

This thesis explores the application of Communities of Practice (CoPs) in Computer Science Education. The work consists of two qualitative studies examining related but distinct populations: (1) K–12 CS teachers and (2) undergraduate CS students. The first study presents a retrospective analysis of conneCTION, an online CoP for K–12 CS educators, identifying strengths, weaknesses, and design considerations that inform future platform development. The second study investigates how participation in a CoP can mitigate negative and exclusionary stereotypes in CS. This study was conducted in an under-explored context: a small, private, religious, Midwestern university, and examines an existing community, the Programming …

A Webcam Eye Tracking Infrastructure For Software Engineering Tasks, Zachary M. Kozak

School of Computing: Dissertations, Theses, and Student Research

Performing eye tracking utilizing commodity webcams has been explored for over a decade, but limited camera quality and sensitivity to head movements have hindered its adoption in research settings. Recent advances in consumer-grade webcams and machine learning methods present an opportunity to improve the accuracy of webcam eye tracking and extend the feasibility of studies beyond controlled laboratory environments.

Current popular webcam eye tracking methods restrict implementations to the browser and rely on continuous user interactions for calibration, limiting the kinds of studies that can be conducted. This thesis presents a feature-based gaze prediction system that incorporates eye geometry and …

Breeding For Diverse Color And Protein Quality In Popcorn And Sweet Corn, Jonathan Niyorukundo

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

Sweet corn and popcorn are important crops consumed globally as vegetable and snack, respectively. They are deemed healthy foods due to high fiber and carotenoid contents, especially in yellow varieties. Commercial varieties are optimized for high-yielding agronomics, and previous efforts were made to improve specific macro- and micronutrient contents. Both sweet corn and popcorn have poor protein quality due to the inadequate essential amino acids such as lysine and tryptophan. Moreover, commercial varieties are predominantly yellow, thereby offering no diversity of other maize colors, which are potentially healthier and more appealing to the consumer. In this project, we sought to …

Unleashing Stress: The Effects Of Training, Bond Strength, And Stress On Pet Dog Behaviors And Health, London Maria Wolff

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

Humans and dogs have formed a unique ability to communicate with each other through evolutionary and developmental mechanisms. This increased communication serves to form dynamic interspecies bonds by facilitating learning and training over the lifetime of a dog. However, it is not known what factors permit the unique capacity of dogs to form bonds with, and learn from, their human companions. Odor is a notable candidate for interspecies communication about emotional states, with studies showing that both dogs and humans use odor information to detect human emotions (Calvi et al., 2020). Possibly, this may include detection of both acute and …

Problems With Small Drinking Water Systems In Developing And Developed Countries: How Do They Compare?, Kurt Kesteloot

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

This dissertation compares the factors that drive the long-term functionality of small drinking water systems (serving fewer than 10,000 people) in developing and developed country contexts, with a focus on groundwater supplies. Using regression analysis in SAS and complementary fuzzy-set Qualitative Comparative Analysis (fsQCA) for developing countries, the study integrates two datasets: 23 Engineers Without Borders project surveys (90+ variables across 14 countries) and a multi-year National Park Service inspection dataset (approximately 1,561 systems; 7,460 recorded deficiencies, enriched with U.S. Census ZIP-code aggregates). In developing countries, statistically significant predictors of success include government cash contributions (odds ratio [OR] ≈ 67.6), …

Open Multi-Agent Systems: The Free-Range-Zoo Framework And Moasei Competition, Ceferino J. Patino Iv

School of Computing: Dissertations, Theses, and Student Research

The field of multi-agent reinforcement learning (MARL) has made significant strides in addressing sequential decision-making problems under uncertainty. However, traditional MARL frameworks assume closed-world settings with fixed agent sets, static task distributions, and unchanging environment dynamics. This thesis presents two complementary contributions that advance the state of open-world multi-agent systems research: (1) the free-range-zoo framework, an open-source environment suite for MARL in open environments featuring dynamic agent populations, evolving task sets, and changing operational frames; and (2) the MOASEI Competition, an international benchmarking event that leverages free-range-zoo to evaluate how artificial agents handle openness in complex, partially observable domains. The …

External Force Control Of Transitional And Turbulent Flows, Cesar Alberto Leos

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

Turbulence in wall-bounded flows governs momentum transport, drag, and energy efficiency in a wide range of engineering systems, yet its response to external forcing remains incompletely understood across transitional and high Reynolds number regimes. This dissertation investigates an active flow control strategy based on spanwise external forcing and demonstrates how it modifies the dynamics of transitional and turbulent channel flows with the objective of identifying the mechanisms through which forcing alters transition, flow physics, and turbulent drag reduction.

Firstly, direct numerical simulations are performed to examine the subcritical transition under external forcing. The onset and sustenance of turbulence are shown …

Exploring The Relations Between Employer Beliefs And Workplace Practices: Organizational Factors And Autism Employment Outcomes, Melinda Ann Henson

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

Autistic individuals experience persistent employment disparities despite interventions targeting individual skills and supports, suggesting that workplace factors also shape employment outcomes. Self-Determination Theory (SDT) posits that workplace environments supporting employee autonomy, competence, and relatedness promote employment outcomes. This study examined SDT-aligned practices and tested associations between employer beliefs about autism as a form of neurodiversity, hiring receptivity, and employment outcomes for Autistic professionals. A preliminary aim was to evaluate the psychometric properties of a newly developed measure, the Workplace Inclusivity and Autonomy Survey (WIAS), designed to assess SDT practices via employer report. Participants included 43 professionals representing a range of …

German Is For You! The Making Of A High School Multikulti German Course, Jennene Aten

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

This teacher self-study examined the process of creating and teaching a multicultural German curriculum. This study necessarily involved observing students as they went through the semester of course work, but students are not the center of the research. I am. This research focuses on what I learned about teaching, specifically my teaching in my subject area and how I could improve my skills and methods.

Germany is an ethnically diverse nation but not usually thought of as such. The presentation of Germany in German language textbooks is generally portrayed as rather monochromatic. Students who study German, specifically in Fairfield, California, …

Improving Drought Science Communication And Accessibility, Lindsay Erin Johnson

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

Effective drought management depends not only on the accuracy of scientific data, but also on how that information is communicated and understood by diverse audiences. This dissertation examines drought communication through the lens of science communication, with a focus on improving readability, accessibility, understandability, and usability of drought information. Using a manuscript-style format, three studies investigate how drought information is written, delivered, and applied. Chapter 1 provides a brief overview and outline of this dissertation. Chapter 2 evaluates the readability of the U.S. Drought Monitor (USDM) national narratives over almost 8 years. Results show that these narratives are consistently written …

Laser Microprocessing Of Metallic And Composite Materials: Nanosecond Pulsed Laser Surface Melting, Laser Shock Peening, And Femtosecond Laser Machining, Qiuchi Zhu

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

This dissertation comprises three parts addressing laser microprocessing of metallic and composite materials through nanosecond pulsed laser surface melting, laser shock peening, and femtosecond laser machining. The first part discusses nanosecond pulsed laser surface melting for corrosion mitigation in stainless steel. Commercial 304 stainless steel (SS) was first used to establish a processing window for stable shallow remelting and rapid resolidification. The approach was then extended to 304L/308L SS welded joints relevant to nuclear dry storage canisters. The results show that nanosecond laser surface melting refines the near-surface microstructures in the heat-affected zone and improved pitting corrosion resistance. Electrochemical and …

A Multimodal Approach For Building Generalizable And Reliable Models Of Longitudinal Experiential Data, Ahatsham Hayat

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

This dissertation studies how to build generalizable and reliable models for longitudinal experiential (LE) data. Such data arises in domains where human behavior, experience, and context evolve over time, including education, behavioral health, and related human-centered settings. These datasets are often heterogeneous, partially observed, temporally structured, and vulnerable to out-of-distribution (OOD) shift, making them difficult to model with conventional machine learning pipelines.

The dissertation develops a multimodal research program that progresses from traditional machine learning and deep learning methods to contextual large language modeling, vision-language modeling (VLM), and finally a frozen-backbone multimodal framework designed to improve robustness and generalization. Across …

Integrated Approaches For Valorization Of Chicken Feather Waste: From Extraction To Application Of Keratin-Based Bioproducts, Muhammad Ehtasham Akram

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

This dissertation explores the optimization of chicken feathers keratin hydrolysate (CFKH) production using alkaline hydrolysis (AH) and sub-critical water hydrolysis (SCWH), focusing on acquiring high keratin yield in the hydrolysate. Then, CFKH along with other locally sourced materials, was used to develop bioplastics with regenerative agriculture properties (BioWRAP), with the ultimate objective of applying it as a soil mulch to suppress weeds in agricultural crops. This work also addresses challenges in process design and industrial scale-up of BioWRAP. Chapter 1 is a literature review that introduces terms like biobased, biodegradable, and bioplastics, materials and methods used to make bioplastics, and …

Program And Proceedings, The Nebraska Academy Of Sciences 1880–2026: 146th Anniversary Year, One Hundred-Thirty-Sixth Annual Meeting

Nebraska Academy of Sciences: Programs and Proceedings

Program and abstracts of the proceedings for the Nebraska Academy of Sciences 136th annual meeting, 2025

Sessions

Aeronautics and Space Science

Anthropology

Biological and Medical Sciences

Earth Sciences

Ecology, Sustainability, and Environmental Science

Physics and Engineering

General Poster Session

2026 Maiben Lecture: Shifting Extremes: Understanding Nebraska’s Changing Climate and Preparing for What Lies Ahead, Deborah Bathke

2026 Friends of Science Awards: Julie Shaffer and Irina Filina

2026 C. Bertrand and Marian Othmer Schultz Colleaguate Schoalrship Award: Piper Ryschon and Bryce Reeson

In Memoriam: Paul Royster

Carmen Manrique De Quintero: A Forgotten Legacy In Colombian Piano Music, Lina Maria Luisa Marín Diaz

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

This doctoral document investigates the life and piano works of Carmen Manrique de Quintero (1871–1931), a pivotal yet overlooked figure in Colombian music history. Positioned as a stylistic bridge between the nineteenth-century estética del salón [salon aesthetics] and the professionalization of the Colombian composer, Manrique de Quintero’s output represents a sophisticated synthesis of European forms and Colombian national rhythms. Despite her membership in the influential Garay artistic lineage and her prolific body of work, her legacy has suffered from editorial blurring, fragmented documentation, and systematic intellectual appropriation. Using a multidisciplinary approach of genealogical reconstruction and artistic archaeology, this study restores …

Transitional And Turbulent Dynamics In Viscoelastic Wall-Bounded Flows, Alexia Martinez Ibarra

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

The addition of small amounts of long-chain polymers to a turbulent flow has been reported to modify the flow phenomena when compared to Newtonian flows, resulting in a significant skin-friction reduction. Although polymer-induced drag reduction has been extensively studied through both experimental and numerical studies, a unified and predictive understanding of the phenomenon is still lacking. This dissertation focuses on better understanding of this phenomenon, particularly on the transitional regime, which remains largely unexplored but is of utmost importance for both practical and fundamental purposes.

Firstly, direct numerical simulations are performed to study the effect of polymers on the laminar-turbulent …

On The Transport Of Chloroplast Lipids, Cailin Smith

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

Chloroplasts are green, photosynthetically active organelles ubiquitous to the plant kingdom. Owing to their cyanobacterial origin, chloroplasts consist of three membranes: the outer envelope, the inner envelope, and the thylakoid, the latter of which is the site of the light-dependent reactions of photosynthesis. Not only do the lipids that make up these membranes delineate aqueous compartments, but they also respond dynamically to developmental and environmental cues, constitute the matrix that scaffolds protein machinery, and even serve as functional components of some proteinaceous complexes. However, while lipids are of vital importance to the structure and function of the chloroplast, the mechanisms …

Integration Of Bayesian Networks And Neural Networks For High-Dimensional Data Analysis, Cooper Schmer

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

High-dimensional biomedical datasets, such as omics data, present significant challenges for predictive modeling due to noise, redundancy, and computational complexity. This thesis proposes a hybrid framework that integrates Bayesian Networks (BNs) and Artificial Neural Networks (NNs) to improve classification performance of such data sets while reducing input dimensionality. Central to this work is a novel feature selection method based on d-separation, a structural property of Bayesian networks that encodes conditional independence relationships.

The proposed approach introduces a count-based d-separation metric to quantify the relevance of variables to a target outcome, along with a thresholding scheme to balance feature selection robustness …

The Impact Of State And Federal Policies On Academic Researchers: Findings From A National Survey, Dylan Ruediger, Chelsea Mccracken, Jonathan Barefield

Copyright, Fair Use, Scholarly Communication, etc.

Key findings

● State and federal policies targeting divisive concepts or DEI are shaping research agendas at scale and across disciplines. Twenty percent of all respondents, and 29 percent of researchers working in states with divisive concepts or similar laws, reported having avoided certain research topics because of state laws and policies.

● Eight percent of respondents representing a wide range of disciplines reported having had a federal grant cancelled in 2025.

● Eleven percent of respondents reported that federal and state policies restricting research activities are compelling them to seek employment out of state, to leave the academy, or …

David Berkowitz, Enzyme-Assisted Organic Synthesis & Nsf Officer, Mark A. Griep, David B. Berkowitz

Department of Chemistry: Faculty Interviews

Dr. Dave Berkowitz was born in Urbana, Illinois. He earned his bachelor's degree in chemistry from the University of Chicago, where he did undergraduate research. Next, he earned his doctorate from Harvard University. However, his advisor, Steve Benner, moved from Harvard to ETH Zurich, also called the Swiss Federal Institute of Technology. Dave accompanied him to Zurich, where he completed his dissertation work. When Dave returned to the U.S., he did a postdoc with the legendary Samuel Danishefsky at Yale University. In 1991, he joined UNL as an assistant professor of chemistry and quickly rose through the ranks. Dave is …

Transport Phenomena Of Multiphase Flow And Slippery Microsphere Suspensions In Confined Space, Ryan Haggerty

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

Understanding multiphase flow has many important environmental and engineering applications. For example, understanding gas flow in porous media is useful for energy storage, petroleum engineering, and contaminant cleanup. Nano- and microparticle transport is vital for enhanced oil recovery techniques and environmental contamination. Despite their relevance to environmental engineering, multiphase flows, especially with concentrated particle suspensions, are still a complex and developing topic. Additionally, hydrophobic surfaces are a relatively new area of research, for while the effects of hydrophobicity are observable, the mechanisms may occur on several scales. Hydrophobicity leads to a property called “slip,” which contradicts the traditional treatment of …

Interview With Orca Award Winner Paul Olson, Unl English; Literature, Curricular Reform, Great Plains Studies, Mark A. Griep, Paul A. Olson

UNL ORCA Interview Series

Paul Olson was awarded the ORCA in 1984. He was born in 1932 in Washburn, Wisconsin. During his youth, his family also farmed in Nebraska and South Dakota. He earned a bachelor’s degree from Bethany College in Lindsborg, Kansas. Next, he earned a master’s in English from the University of Nebraska, had a Fulbright fellowship to spend a year at London University in England, and earned his doctorate in medieval and Renaissance studies from Princeton University in New Jersey. In 1957, he joined UNL as an assistant professor of English and was soon promoted to full professor. One of his …

Antecedents And Consequences Of Consumer Behavior In Circular Fashion: Cognitive, Normative, And Behavioral Pathways Shaping Purchase And Participation Intentions, Mahmudul Hasan Sabuj

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

The increasing environmental impact of the fashion industry has intensified the need for a systemic transition from linear to circular production and consumption models. Despite growing interest in circular fashion, there remains a limited understanding of the underlying behavioral dimensions that drive consumer engagement in sustainable practices. Grounded in the Theory of Planned Behavior (TPB) and Norm Activation Theory (NAT), this study examines consumer behavior through an integrated framework capturing cognitive, social, and normative influences.

Using data collected from a structured online survey (N = 575), the study employs Exploratory Factor Analysis (EFA), reliability analysis, and multiple regression techniques to …

Unl Emeriti And Retirees Association Newsletter, Spring 2019

UNL Emeriti and Retirees Association: Newsletters and Other Materials

University of Nebraska-Lincoln Emeriti and Retirees Association Newsletter, Spring 2019

Water Current, Volume 58, No. 1, Spring 2026

Water Current Newsletter

No abstract provided.

Guidance For Left-Turn Flashing Yellow Arrow (Fya) Implementation In Nebraska, Aemal Khattak, Li Zhao, Frank Selase Dzawu

Nebraska Department of Transportation: Research Reports

This research evaluates the safety performance of flashing yellow arrows (FYA) and driver behavioral responses in Nebraska, using data from 324 FYA intersections (Lincoln 160; Omaha 164) to develop evidence-based implementation guidance. The study addresses critical knowledge gaps in local driver acceptance patterns, the effectiveness of phasing configurations, and a comprehensive safety assessment that integrates crash and conflict analyses. The methodology employed four complementary analyses: (1) negative binomial crash frequency modeling of 3945 unique left turn crashes (2015-2024) across Lincoln and Omaha; (2) binary logistic regression of 948 gap acceptance decisions across 43 intersections; (3) linear regression of post-encroachment time …

Update Of Intersection/Interchange Guidelines For Rural Expressways In Nebraska, Aemal Khattak, Mm Shakiul Haque

Nebraska Department of Transportation: Research Reports

Nebraska Department of Transportation (NDOT) staff frequently decide on changes to existing two-way stop- controlled (TWSC) intersections on rural expressway to alternative facilities, such as a restricted crossing U-turn (RCUT), a roundabout, a signalized intersection, or an interchange. As Nebraska makes progress toward completion of its expressway system, updated and defensible decision-making is essential for conversion of TWSC highway intersections. NDOT’s existing guidelines, developed in the 1990s, no longer reflect current operations, safety performance, or modern intersection designs.

This project updated and expanded NDOT’s guidance using contemporary traffic operational and safety data, combined with robust microsimulation and safety performance modeling. …

Ultra-High-Performance Concrete (Uhpc) For Bridge Deck Overlay And Structural Deck Repair, Jiong Hu, George Morcous, Akbota Aitbayeva, Ming Gerges

Nebraska Department of Transportation: Research Reports

Ultra-high-performance concrete (UHPC) is an advanced cementitious material known for its exceptional strength and durability, making it an ideal material for bridge deck overlays and repairs that address the common issue of premature deck deterioration. Conventional UHPC is typically flowable and self-leveling, which makes it unsuitable for deck surfaces with cross-slopes and/or sloped vertical profiles. Therefore, a highly thixotropic UHPC that responds well to vibration while remaining stable on sloped surfaces is needed for overlay applications. Mixtures with varying binder content, water-to-binder ratio, fiber content, and dosages of admixtures were developed and evaluated. Two of the most effective and economical …

A Software-Defined Radio Testbed For Mimo-Ofdm Communications, Chaz G. Maschman

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

In this thesis, we implement a testbed for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems via GNU Radio. Specifically, we implement a configurable framework for the construction of MIMO-OFDM software-defined radio (SDR) systems as a GNU Radio module. The GNU Radio MIMO-OFDM module consists of multiple algorithmic blocks necessary for implementation of a MIMO-OFDM system. This includes a library for the generation of orthogonal or pseudo-random pilot sequences, amendments to the Schmidl-Cox protocol for MIMO synchronization, and the creation of click-and-drag GNU Radio blocks implementing the conversion of arbitrary data sent via external programs to MIMO-OFDM frames, the initial …

Gamma Sigma Delta, Nebraska Chapter Newsletter, Issue #69 Spring 2026

Gamma Sigma Delta, Nebraska Chapter: Newsletters

President's message, Dustin Loy

Undergraduate Scholarship Awards

2026 Chapter Officers and Committees

Faculty Awards

Membership info and dues form

Grad Student Scholarship

Award of Merit

NU Foundation Fund

New Initiates

Save the Date

In Memoriam:
Kara Daye Heideman (March 31, 1980-December 11, 2025)
L. Dale Van Vleck (June 11, 1933-December 23, 2025)
James (Jim) Eugene Specht (September 12, 1945-February 13, 2026)
Irvin Thomas Omtvedt (June 12, 1935-April 6, 2026)
Fayrene L. Hamouz (June 6, 1946-April 8, 2026)
Robert L. Raun (April 22, 1928-April 22, 2026)