Digital Commons Network^™

Implications And Recommendations For U.S. Security Alliances: South Korea's Anticipated Nuclear Proliferation, Ethan Czapla

Honors Program: Senior Projects (Public)

In 2023, South Korean President Yoon Suk-yeol suggested South Korea should consider pursuing a sovereign nuclear weapon arsenal, a striking departure from the history of South Korea’s non-proliferation posture. The pursuit of a nuclear capability or redeployment of nuclear weapons has gained traction among the South Korean public, as over 70% supported acquiring a sovereign nuclear capability in 2021. In this paper, I argue nuclear proliferation in South Korea would (1) destabilize regional security, (2) diminish U.S. security alliances, and (3) undermine the international rules-based order regarding non-proliferation and offer policy recommendations for U.S. defense practitioners in order to boost …

Adolescent Algorithm Addiction, Canyon Skare

Honors Program: Senior Projects (Public)

There’s no question that online Social Networking Sites have contributed to the sharp decline in mental health among adolescents. This thesis explores a number of Addictive Online Behaviors that have contributed to negative mental health outcomes, namely examining at total screentime, level of engagement, and total number of accounts one has in relation to phone addiction and social media addiction. It was found that total screentime and total number of accounts were more strongly correlated with social media addiction than phone addiction. Additionally, differences in app usage among gender was explored, finding that boys favored YouTube and Discord while Girls …

Aphid-Ant Relationships: The Role Of Cuticular Hydrocarbons And Different Chemical Stimuli In Triggeringmutualistic Behavior, Amged El-Harairy, Ahmed El-Harairy, Alaa Mahfouz

Department of Chemical and Biomolecular Engineering: Faculty Publications

In ant-aphid interactions, various aphid species offer honeydew to the ant partner and increase their density by ant attendance, whilst others never attend ant species, in which case ants tend to treat them as prey. In this regard, ants should have the ability to distinguish myrmecophile aphid species from non-mutualistic species, so that mutualistic aphids will be accepted as partners rather than prey. Although ant-aphid interactions are now the focus of chemical ecology studies, the role of the different chemical stimuli in determining mutualistic interactions has not been completely clarified. Therefore, we have investigated the cuticular hydrocarbon profile of four …

Distribution Fitting And Anova Test To Analyze Pavement Sensing Patterns For Condition Assessments, Dada Zhang, Chun-Hsing Ho

Durham School of Architectural Engineering and Construction: Faculty Publications

Purpose – The purpose of this paper is to investigate the vehicle-based sensor effect and pavement temperature on road condition assessment, as well as to compute a threshold value for the classification of pavement conditions.

Design/methodology/approach – Four sensors were placed on the vehicle’s control arms and one inside the vehicle to collect vibration acceleration data for analysis. The Analysis of Variance (ANOVA) tests were performed to diagnose the effect of the vehicle-based sensors’ placement in the field. To classify road conditions and identify pavement distress (point of interest), the probability distribution was applied based on the magnitude values of …

Will Saf Turbocharge The Corn Ethanol Market?, Richard K. Perrin, Lilyan E. Fulginiti, Felipe Miranda De Souza Almeida

Cornhusker Economics

The long-run outlook for the corn ethanol industry is questionable, due to a transition to electric and hybrid vehicles. One source of hope for the long run is the potential demand for producing Sustainable Aviation Fuel (SAF). SAF is a key component in the United States Aviation Climate Action Plan, a path to net-zero greenhouse gas (GHG) emissions in the aviation industry by 2050. Demand for ethanol for SAF offers hope to the ethanol industry, but it depends a great deal on policy decisions that are being made now. Here we sketch out this story.

Based on the information available …

Pollen-Mediated Gene Flow From Herbicide-Resistant Yellow Corn To Non-Genetically Engineered Food-Grade White Corn, Mandeep Singh, Vipan Kumar, Stevan Z. Knezevic, John L. Lindquist, Suat Irmak, Santosh Pitla, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Nebraska is the number one producer of food-grade white corn in the United States. Pollen-mediated gene flow (PMGF) from genetically engineered high alpha-amylase corn, known as Enogen corn, to food-grade white corn can have undesirable outcomes. Alpha-amylase can convert starch in white corn to sugar during or after its processing, degrading the quality of processed products. Thus, proximity to Enogen corn puts white corn production at risk. The objectives of this study were to evaluate the PMGF from herbicide-resistant yellow corn to food-grade white corn and assess the significance of wind speed and direction. Field experiments were set up using …

Combining Multi-View Uav Photogrammetry, Thermal Imaging, And Computer Vision Can Derive Cost-Effective Ecological Indicators For Habitat Assessment, Qiao Hu, Ligang Zhang, Jeff Drahota, Wayne Woldt, Dana Varner, Andy Bishop, Ted Lagrange, Christopher M. U. Neale, Zhenghong Tang

School of Natural Resources: Faculty Publications

Recent developments in Unmanned Aircraft Vehicles (UAVs), thermal imaging, and Automachine learning (AutoML) have shown high potential for precise wildlife surveys but have rarely been studied for habitat assessment. Here, we propose a framework that leverages these advanced techniques to achieve cost-effective habitat quality assessment from the perspective of actual wildlife community usage. The framework exploits vision intelligence hidden in the UAV thermal images and AutoML methods to achieve cost-effective wildlife distribution mapping, and then derives wildlife use indicators to imply habitat quality variance. We conducted UAV-based thermal wildlife surveys at three wetlands in the Rainwater Basin, Nebraska. Experiments were …

Synergistic Preparation And Application In Pcu Of Α‑Calcium Sulfate Hemihydrate Whiskers From Phosphogypsum And Electrolytic Manganese Residue, Ting Wang, Xuan Ke, Jia Li, Ying Wang, Weiwei Guan, Xia Sha, Chenjing Yang, Tian Zhang

Department of Civil and Environmental Engineering: Faculty Publications

The α-calcium sulfate hemihydrate whiskers (α-CSHWs) were first prepared using phosphogypsum (PG) and electrolytic manganese residue (EMR) as raw materials for coating urea, demonstrating excellent controlled-release properties. The effects of different reaction conditions on α-CSHWs, achieved by optimizing the reaction time, the concentrations of NH₄⁺, Mn²⁺, and other factors, were discussed. Results showed that when the EMR content was 25 wt%, the reaction temperature was 100 °C, and the reaction time was 3 h, α-CSHWs with a length-to-diameter ratio of 39 were obtained. Through experiments and density functional theory (DFT), the mechanism of α-CSHWs preparation …

Spatiotemporal Reaction Dynamics Control In Two-Photon Polymerization For Enhancing Writing Characteristics, Aofei Mao, Sarah Fess, Nada Kraiem, P. Li, Zhipeng P. Wu, Qiuchi Zhu, Xi Huang, Peixun Fan, Bai Cui, Jean-Francois Silvain, Suxing Hu, Mitchell Anthamatten, Sean P. Regan, David Harding, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Since 2001, 3D microfabrication based on two-photon polymerization (TPP) has drawn extensive attention and interest in biology, optics, photonics, material science, and high-energy physics. The in-volume fabrication capability due to the threshold behavior of two-photon absorption enables TPP higher flexibility compared with other nanofabrication techniques. However, as determined by the in-volume fabrication feature as well as various reaction dynamics, the writing characteristics of TPP, such as throughput, accuracy, surface quality, and fabrication capability, are still limited. Herein, a comprehensive study is performed on the spatiotemporal behavior of reaction dynamics during TPP fabrication, mainly focusing on spatiotemporal characteristics of radical diffusion, …

Up-Regulation Of Non-Photochemical Quenching Improves Water Use Efficiency And Reduces Whole-Plant Water Consumption Under Drought In Nicotiana Tabacum, Benjamin Turc, Seema Sahay, Jared Haupt, Talles De Oliveira Santos, Geng Bai, Katarzyna Glowacka

Center for Plant Science Innovation: Faculty Publications

Water supply limitations will likely impose increasing restrictions on future crop production, underlining a need for crops that use less water per mass of yield. Water use efficiency (WUE) therefore becomes a key consideration in developing resilient and productive crops. In this study, we hypothesized that it is possible to improve WUE under drought conditions via modulation of chloroplast signals for stomatal opening by up-regulation of non-photochemical quenching (NPQ). Nicotiana tabacum plants with strong overexpression of the PsbS gene encoding PHOTOSYSTEM II SUBUNIT S, a key protein in NPQ, were grown under differing levels of drought. The PsbS-overexpressing lines lost …

Development Of Quantitative Structure Activity Relationships (Qsars) For Predicting The Aggregation Of Tio2 Nanoparticles Under Favorable Conditions, Jaewoong Lee

Department of Civil and Environmental Engineering: Faculty Publications

This study developed multi-linear regression (MLR) quantitative structure-activity relationships (QSARs) to predict n-TiO₂ aggregation in the presence of high concentrations of representative emerging organic contaminants (EOCs), which presented favorable conditions to interaction with n-TiO₂. The largest diameter change (Δ 517 nm at 0 h and Δ 1164 nm at 12 h) of n-TiO₂ was observed by estrone, while the smallest diameter change (Δ -114 nm at 0 h and – 4 nm at 12 h) was observed by lincomycin during experimental periods. In addition, the zeta potential changes of n-TiO₂ were …

A Deep Learning Convolutional Neural Network For Antenna Near-Field Prediction And Surrogate Modeling, Md Rayhan Khan, Constantinos L. Zekios, Shubhendu Bhardwaj, Stavros V. Georgakopoulos

Department of Electrical and Computer Engineering: Faculty Publications

This study investigates the use of deep learning techniques for building a generalized surrogate model that can accurately and very efficiently predict antenna performance parameters. Notably, we focus on applications where a substantial amount of simulation time is required and prior data is available for deep learning use. Specifically, for these applications, we introduce deep learning models that efficiently and reliably model the near-field of the antenna. These models, in turn, accurately predict far-field properties and essential antenna metrics, such as the reflection coefficient. To demonstrate the efficiency of our method, the widely used rectangular patch antenna is considered, encompassing …

Synthesis Of Current Evidence On Factors Influencing The Suitability Of Synthetic Biodegradable Mulches For Agricultural Applications: A Systematic Review, Michael Madin, Katherine Nelson, Kanji Fatema, Karina Schoengold, Abhilekha Dalal, Ikenna Onyekwelu, Rushrukh Rayan, Sanaz Saki Norouzi

Department of Agricultural Economics: Faculty Publications

Mulching practice offers farmers an opportunity to minimize the effects of drought, water loss, and soil erosion on crop production. Plastic film is widely used as a mulching material; however, contamination of arable lands by residual plastic has become a serious concern. Synthetic biodegradable mulch films and sprays may offer a more sustainable alternative to plastic films, however current evidence on the factors that influence the suitability of these products for agricultural applications is fragmented, making it unclear under what conditions these products meet agronomic, environmental, and societal needs. We address this gap by conducting a systematic review of studies …

Microclimate, An Important Part Of Ecology And Biogeography, Julia Kemppinen, Jonas J. Lembrechts

School of Biological Sciences: Faculty Publications

Brief introduction: What are microclimates and why are they important? Microclimate science has developed into a global discipline. Microclimate science is increasingly used to understand and mitigate climate and biodiversity shifts. Here, we provide an overview of the current status of microclimate ecology and biogeography in terrestrial ecosystems, and where this field is heading next.

Microclimate investigations in ecology and biogeography: We highlight the latest research on interactions between microclimates and organisms, including how microclimates influence individuals, and through them populations, communities and entire ecosystems and their processes. We also briefly discuss recent research on how organisms shape microclimates from …

Composting Reduces The Risks Of Resistome In Beef Cattle Manure At The Transcriptional Level, Yuepeng Sun, Zachery R. Staley, Bryan Woodbury, Jean-Jack Riethoven, Xu Li

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Transcriptomic evidence is needed to determine whether composting is more effective than conventional stockpiling in mitigating the risk of resistome in livestock manure. The objective of this study is to compare composting and stockpiling for their effectiveness in reducing the risk of antibiotic resistance in beef cattle manure. Samples collected from the center and the surface of full-size manure stockpiling and composting piles were subject to metagenomic and metatranscriptomic analyses. While the distinctions in resistome between stockpiled and composted manure were not evident at the DNA level, the advantages of composting over stockpiling were evident at the transcriptomic level in …

On Skew-Symmetric Splitting And Entropy Conservation Schemes For The Euler Equations, Björn Sjögreen, H.C. Yee

United States National Aeronautics and Space Administration: Publications

The Tadmor type of entropy conservation formulation for the Euler equations and various skew-symmetric splittings of the inviscid flux derivatives are discussed. Numerical stability of high order central and Padé type (centered compact) spatial discretization is enhanced through the application of these formulations. Numerical test on a 2-D vortex convection problem indicates that the stability and accuracy of these formulations using the same high order central spatial discretization are similar for vortex travel up to a few periods. For two to three times longer time integrations, their corresponding stability and accuracy behaviors are very different. The goal of this work …

Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Articles
Chapters in Books
Books
Field Guides
Geologic Maps
Other Maps
Cover Photographs
Other Photographs
Newspaper and Other Articles
Test-Hole Logs
Television Programs
Geonotes
Abstracts
Reviews
Manuscripts Accepted (A), Submitted (S), or in Preparation (P)
Geologic Maps in Press
Geologic Maps-Nebraska
Public Documents
Miscellaneous Publications
Editing

Updated March 2024

Field Research Report: Results From The Enreec Vri Field For The 2021, 2022, And 2023 Crop Seasons, Derek M. Heeren, Ali T. Mohammed, Eric Wilkening, Christopher M. U. Neale, Alan L. Boldt, Ankit Chandra, Precious Nneka Amori, Ivo Z. Goncalves, Yeyin Shi, Guillermo R. Balboa

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Long-term irrigation management research has been conducted from 2014 to 2023 for corn and soybean at the Eastern Nebraska Research, Extension, and Education Center (ENREEC) Variable Rate Irrigation (VRI) Field located in subhumid east-central Nebraska (in the Lower Platte North Natural Resources District). The objective of this report was to present the overall results from the VRI Field for 2021 to 2023. Across the three growing seasons, there were the following irrigation treatments: Best Management Practice (BMP), 50% BMP, 125% BMP, rainfed, Spatial ET Modeling Interface (SETMI), SDD1, SDD2, machine-learning-based Cyber-Physical System (CPS), a student team recommended rate, and industry …

Integrated Stem Professional Development: Utilizing Best Practices In An Online Format, Sarah Haines, Sumreen Asim, Jeanna R. Wieselmann, Deepika Menon

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

Online professional development (PD) can reach teachers from widespread areas. Here, we describe PD activities that are part of a project focused on integrated science, technology, engineering, and mathematics (iSTEM) teaching self-efficacy and effectiveness among early-career elementary teachers. Toward our objective of building a community of elementary teachers focused on improving their iSTEM teaching, we are conducting online PD institutes over four summers. These PD institutes are designed using Desimone’s five critical features of effective PD: content focus, active learning, coherence, duration, and collective participation. Our institutes engage teachers in an initial synchronous online session, which is followed by independent …

Stage And Discharge Prediction From Documentary Time-Lapse Imagery, Kenneth W. Chapman, Troy E. Gilmore, Mehrube Mehrubeoglu, Christian D. Chapman, Aaron R. Mittelstet, John E. Stranzl Jr.

Conservation and Survey Division: Faculty and Staff Publications

Imagery from fixed, ground-based cameras is rich in qualitative and quantitative information that can improve stream discharge monitoring. For instance, time-lapse imagery may be valuable for filling data gaps when sensors fail and/or during lapses in funding for monitoring programs. In this study, we used a large image archive (>40,000 images from 2012 to 2019) from a fixed, ground-based camera that is part of a documentary watershed imaging project (https://plattebasintimelapse.com/). Scalar image features were extracted from daylight images taken at one-hour intervals. The image features were fused with United States Geological Survey stage and discharge data as response variables …

Pollinator Communities And Their Ecosystem Services At Conservation Grasslands And Adjacent Croplands, Araceli Gomez Villegas

Department of Entomology: Dissertations, Theses, and Student Research

Pollinators are intrinsically linked to the success of unmanaged and managed ecosystems by providing pollination services that aid in the reproduction of wildflowers and many crops. Land use change, habitat loss, fragmentation, and related landscape-level phenomena (for example, increased pesticide exposure) threaten pollinators and have been associated with population declines. In the Midwestern region of the United States, land conversion of native prairies and grasslands to row-crop agriculture has been one of the largest contributors to pollinator habitat loss. Conservation programs, such as the Conservation Reserve Program, have worked towards removing environmentally sensitive lands from agriculture production and enrolling them …

Weakly Supervised Attention-Based Recognition Under Spectral, Turbulence, And Resource Variations, Kshitij Naresh Nikhal

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

While supervised optimization paradigms are ubiquitous across diverse recognition systems, the risk of over-fitting and increasing bias have limited their applicability.

This dissertation focuses on unsupervised learning—learning without precisely curated data—and argues that unsupervised learning methods can enable both discriminability and generalizability. Through the use of attention-based machine learning and advanced clustering, unsupervised methods are able to focus on fine-grained information in images without any explicit supervision. The dissertation introduces a domain-bridging framework for tasks like cross-spectrum matching and long-range recognition, utilizing intra-domain clustering and inter-domain matching to generate pseudo-labels. Additionally, a hash-based network is proposed to accelerate the search …

Narratives Of Reproductive Control In The American Eugenics Movement, Cassandra M. Provost

Honors Program: Senior Projects (Public)

In this paper, I will explore the eugenics movement as a pseudo-scientific political, social, and legal phenomenon which had a devastating historical impact on America’s most vulnerable women, as well as briefly discuss its residual effects on contemporary reproductive rights conversations, through the lens of literature. Using an interdisciplinary discourse and narrative analysis approach, I identify two distinct themes within the explored narratives: (1) the importance of a government’s attempt to override a person’s autonomy by destroying the person’s ability to reproduce, and (2) the impropriety of actions based on a negative attitude toward disabled or undesirable persons. In my …

Quantum Computing And U.S. Cybersecurity: A Case Study Of The Breaking Of Rsa And Plan For Cryptographic Algorithm Transition, Helena Holland

Honors Program: Senior Projects (Public)

The invention of a cryptographically relevant quantum computer would revolutionize computing power, transforming industry and national security. While a theoretical possibility at the time of this writing, the ability of quantum algorithms to solve the factoring and discrete logarithm problems, upon which all currently employed public-key cryptography depends, presents a serious threat to digital communications. This research examines both the mathematics and government policy behind these risks and their implications for cybersecurity. Specifically, a case study of RSA, Shor’s algorithm, and the American Intelligence Community’s plan to transition toward quantum-resistant algorithms is presented to analyze quantum threats and opportunities and …

Evaluation Of Ndot’S Sediment Barrier Practices Using Performance Data, Michael A. Perez, Wesley N. Donald, J. Blake Whitman, Brian G. Roche

Nebraska Department of Transportation: Research Reports

To protect waterways adjacent to construction projects with disturbed land, a 50 ft (15 m) vegetated buffer or equivalent sediment controls are required. However, there is little guidance on the effectiveness of vegetated buffers in removing sediment or how sediment barriers can aid shorter buffers or replace buffers. A modeling methodology was developed and used to determine the performance of 11,664 50 ft (15 m) vegetated buffer configurations with Nebraska conditions; sediment capture averaged 92.6% and ranged from 18.5% to 99.5%. To determine the performance of Nebraska Department of Transportation standard and modified sediment barrier installations, a large-scale testing methodology …

Soil Nitrate Prediction Using Ftir-Atr, Vis-Nir, And Raman Spectroscopy, Sabiha Ferdous

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

Fourier transform infrared spectroscopy (FTIR) combined with Attenuated total reflectance (ATR), Visible-Near Infrared spectroscopy (Vis-NIR), and Raman spectroscopy (RS) are non-destructive techniques for rapid determination of nitrogen compounds in soil. Leveraging FTIR-ATR and Vis-NIR spectra using partial least squares regression (PLSR) modeling, the study aims to predict soil nitrate content and explored the feasibility of Raman spectroscopy to detect nitrate (NO₃^-), nitrite (NO₂^-), and ammonium (NH₄⁺) in soil. Soil samples were collected from four different fields, dried, sieved (2mm), and then used for collecting spectra (FTIR-ATR and Vis-NIR). Laboratory analysis was …

Integrated Stem Professional Development: Utilizing Best Practices In An Online Format, Sarah Haines, Sumreen Asim, Deepika Menon, Jeanna Wieselmann

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

Summary

• STEM Career focus

o Children’s literature integration

o Resources shared on Canvas Site

o Vicarious experiences--classroom video

• Engineering o Modeling of integrated STEM lessons with participants

o Observe STEM lessons with STEM OP debrief

• Lessonplandesignandfeedback

Rural Student-Home Community Engagement Impact As A Result Of Study Abroad Experiences: From Preparation Through Return, Todd M. Karr

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

This qualitative study utilized a constructivist grounded theory approach to understand how rural students engaged with people in their home community as it related to before, during, and after their study abroad experience and what impact that engagement had on their experiences. Participants included 15 students who self-identified as being from a rural background that studied abroad for a minimum of one semester. Participants included students from one of two large, public universities in the state of New Mexico. Data collection included two semi-structured, in-depth interviews with each participant.

The study used a constant comparison method to generate a theory …

Bermad: Batch Effect Removal For Single-Cell Rna-Seq Data Using A Multi-Layer Adaptation Autoencoder With Dual-Channel Framework, Xiangxin Zhan, Yanbin Yin, Han Zhang

Department of Food Science and Technology: Faculty Publications

Motivation: Removal of batch effect between multiple datasets from different experimental platforms has become an urgent problem, since single-cell RNA sequencing (scRNA-seq) techniques developed rapidly. Although there have been some methods for this problem, most of them still face the challenge of under-correction or over-correction. Specifically, handling batch effect in highly nonlinear scRNA-seq data requires a more powerful model to address under-correction. In the meantime, some previous methods focus too much on removing difference between batches, which may disturb the biological signal heterogeneity of datasets generated from different experiments, thereby leading to over-correction.

Results: In this article, we …

Securing Synchrophasors Using Data Provenance In The Quantum Era, Kashif Javed, Mansoor Ali Khan, Mukhtar Ullah, Muhammad Naveed Aman, Biplab Sikdar

School of Computing: Faculty Publications

Trust in the fidelity of synchrophasor measurements is crucial for the correct operation of modern power grids. While most of the existing research on data provenance focuses on the Internet of Things, there is a significant need for effective malicious data detection in power systems. Current methods either fail to detect malicious data modifications or require certain Phasor Measurement Units (PMUs) to be physically secured. To solve these issues, this paper presents a new protocol to establish data provenance in synchrophasor networks. The proposed protocol is based on Physically Unclonable Functions (PUFs) and harnesses the principles of quantum unreality and …