Digital Commons Network^™

Mathematical Model For Helically Propagating Spatially Multiplexed Mimo Channels Inside Single Core Optical Fibers, Ibrahim Barka

Theses and Dissertations

It all started when our curiosity was sparked by observing light beams from a Multi-Channel Laser Source precisely coupled into a single-core optical fiber positioned on an optical bench in the lab. The multiplexed light beams, characterized by different spatial azimuthal angles, were guided by the fiber, tracing helical paths and producing a bright central spot with concentric rings depending on the launched angles, a phenomenon we came to call Spatial Domain Multiplexing (SDM). Conventional concepts of hybrid and LP modes couldn’t fully explain the behavior of SDM modes, leading us to the question of the types of field configurations …

Intent Visualization In Human-Agent Teams, Rahul Tushar Mehta

Theses and Dissertations

Despite advances in autonomous systems, effective collaboration between humans and intelligent agents remains a significant challenge, particularly in shared-control scenarios. This study investigates how intent visualization affects human-agent collaboration in telecollaboration scenarios, examining its impact on team performance, operator trust, and workload. Using a custom simulation environment and Wizard-of-Oz methodology, we conducted an experiment with 13 participants who completed exploration tasks under two conditions: a baseline interface and an enhanced interface with intent visualization. Results showed that while intent visualization did not significantly improve objective performance metrics, it led to a 22.6\% increase in explicit disagreements between operators and the …

Dissecting Metabolic Landscape Of Alveolar Macrophage, Sunayana Malla

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

The highly plastic nature of alveolar macrophage (AM) plays a crucial role in the defense against inhaled particulates and pathogens in the lungs. Depending on the signal, AM acquires either the classically activated M1 phenotype or the alternatively activated M2 phenotype. In this study, we investigate the metabolic shift in the activated phases of AM (M1 and M2 phases) by reconstructing context specific genome-scale metabolic (GSM) models. Metabolic pathways such as pyruvate metabolism, arachidonic acid metabolism, chondroitin/heparan sulfate biosynthesis, and heparan sulfate degradation are found to be important driving forces in the development of the M1/M2 phenotypes. Additionally, we formulated …

The Viability Of Styrofoam Beads In Concrete Mixtures, Colin Edward Sykes

Construction Management

This experiment revolved around the idea that an aggregate replacement in a concrete mixture could not only maintain its structural integrity but increase its sustainability as well. This idea was formulated into the experiment of embedding Styrofoam beads into concrete. The outcome of this experiment showed the compressive strength of the concrete increased the greatest with the substitution of Styrofoam beads for fine aggregate up to 20%. This 20% Styrofoam replacement mixture exhibited an 189% increase in compressive strength when compared to the control group in the third week of testing. In addition to this impressive compressive strength, the weight …

The Use Of Augmented Reality (Ar) Technology In Construction, Luke Zamlich

Construction Management

Building Information Modeling (BIM) has revolutionized construction by replacing traditional paper-based methods with advanced software, improving data management and project workflows. However, as projects become more complex, challenges like communication gaps and design errors persist, often leading to cost overruns. Augmented Reality (AR) is an emerging technology that could address some of these issues by enhancing real-time visualization and collaboration, helping avoid costly rework. Despite its potential, AR remains underutilized in the construction industry. This paper explores the feasibility of integrating AR into modern construction workflows to complement BIM models and improve on-site project management. A literature review highlights AR’s …

Building Safely: How Spanish Specific Safety Can Impact Job Sites, Luis D. Aguilar Montano

Construction Management

This project explores how Spanish Specific Safety Training is being approached in the construction industry, with an attempt to identify some possible issues associated with language barriers and accessibility to these trainings. This research involved data collection through thirty analytical surveys, in addition to conducting three semi-structured interviews with construction workers and supervisors. The focus of the data collection was to gain insights into several key areas, including training accessibility, workplace injuries, language barriers, and worker comfort. The survey results indicated strong support for Spanish-language safety training, with respondents recognizing its potential to improve safety and overall worker comfort. Many …

A Comparison Of Mass Timber Perceptions Among Construction Professionals Over Time, Josh A. Higginson

Construction Management

Mass timber is a relatively new construction building material consisting of large-scale engineered wood products such as cross-laminated timber (CLT) and glue-laminated timber (glulam). It is gaining attention as a sustainable alternative to traditional steel and concrete, offering benefits such as reduced carbon emissions and enhanced aesthetic appeal. Despite being used on notable projects recently, it is not yet widely accepted by the industry as a whole. This study investigates the evolving awareness, benefits, and challenges associated with mass timber construction among U.S. construction professionals. Through a survey of over 100 construction practitioners, primarily from Cal Poly’s Construction Management Advisory …

Caed Shop Entrance Wall Redesign, Theodore Haoran Khuong, Joelle Schalesky, Ellen Elizabeth Untalan, Katherine Evalyn Timbes

Construction Management

This paper details the preconstruction process involving the replacement and redesign of the north wall at the CAED Support Shop at Cal Poly, San Luis Obispo. Accomplished by an interdisciplinary team of Architectural Engineering and Construction Management students, this project explores the requirements and procedures of generating a project proposal to submit to Cal Poly Facilities Management. The project, initiated in the fall of 2024, aimed to redesign the wall aligned with the adjacent Engineering West building and replace it with a CMU low lift grouted wall. The CAED Support Shop is offered as a resource to all CAED students …

Cal Poly Gateway Decathlon Deliverable 3: Cost Estimate Development, Ruby Maria Sierra

Construction Management

The Gateway Decathlon is a global competition where university teams design, build, and operate sustainable, energy-efficient, and cost-effective homes using advanced technologies and materials. Teams create homes with renewable energy, energy-efficient systems, and sustainable materials. The competition evaluates design, energy efficiency, sustainability, and market viability. Currently, teams are working on Deliverable 3, which includes technical documentation, architectural plans, energy simulations, and cost analyses to ensure project feasibility. This deliverable bridges the design and construction phases and sets the foundation for building and operating the homes, helping to advance sustainable building practices and energy-efficient solutions.

Microbiome Variation In Production Phenotypes And The Role Of Colonization History In Microbiome Establishment, Seidu Adams

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

Ruminant-based agriculture is expected to continue to be a major contributor to food security to feed the growing population. At the heart of nutrient degradation of complex organic matter within the rumen are its microbes. These microbes can convert otherwise unusable organic matter into usable protein and energy and can provide up to 50% of the animal’s protein needs and up to 70% of the energy needs. The microbial functional capacity within the rumen determines the nutrients utilized and the end products of fermentation. However, our understanding of microbial functional capacity within the rumen and factors that influence the rumen …

Domain-Specific Machine Learning Approaches For Geospatial Problems, Shine Bedi

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

This dissertation explores novel algorithms for complex geospatial problems at the intersection of environmental, social, and computational sciences. Emphasizing the unique challenges of the geospatial domain, particularly the deviation from the independent and identical distribution (IID) assumption, the research spans various methodologies across different domains, demonstrating the benefits of specialized approaches in spatial analysis.

First, we show that machine learning techniques can be effectively used in environmental modeling, which often has severe class imbalance challenges. Using artificial neural networks (ANN), support vector machines (SVM), and extreme gradient boosting (XGB) and techniques to address class imbalance provides insights into groundwater quality …

Dynamics Of Flexible Freestanding Structures Under Ground Motion Excitation, Seyed Mohammadreza Farooghi Mehr

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

Freestanding structures are characterized by being unattached at the base, exhibiting rigid or flexible motion under ground motion excitation with various potential responses including rocking (rotation at the base about corner points), pure sliding, slide-rocking, and overturning. While rigid freestanding structures have been extensively studied, the behavior of flexible freestanding structures—particularly the interaction between modes involving sliding—remains underexplored. Existing literature has focused on the deformation and rocking motions of flexible freestanding structures through both analytical and experimental approaches, which have shown indications of sliding at the base. These findings highlight the necessity of incorporating sliding motion into analytical models to …

Deep Learning Vision-Based Bridge Inspection With Resource-Constrained Unmanned Aircraft Systems, Ji Young Lee

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

Bridge inspection is critical for ensuring structural integrity, extending the service life of infrastructure, and minimizing maintenance costs. As bridges age and endure increasing loads, regular inspections help detect early signs of wear, such as cracks or corrosion, that could impact safety and performance. However, traditional inspection methods are labor-intensive, requiring significant time, specialized equipment, and manual access to challenging areas, which can lead to costly disruptions. Additionally, reliance on human inspectors introduces subjectivity, with assessments varying by individual expertise. These factors highlight the inefficiencies and safety risks in current inspection practices, underscoring the need for more objective, efficient solutions. …

Improving Thermionic Power Generation Via The Reduction Of Emission Barriers, Chace E. Franey

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This thesis investigates methods to improve the performance of thermionic energy converters (TECs) by reducing the emission barriers. A TEC generates electricity from thermal energy when electrons are emitted from a hot electrode (the emitter) through a vacuum gap and absorbed by a cooler electrode (the collector). Due to their lack of working fluids and inherently compact nature, TECs have garnered attention over the years for their potential as a means of power generation in space or high-grade waste heat recovery. Historically, however, the practical implementation of TECs has been hindered by significant technical challenges. Recent advancements in microfabrication techniques …

Electrochemical Treatment Of Mining And Oilfield Wastewater Using Recycled Titanium Alloy Electrodes, Sean Michael Thompsen

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This thesis explores the integration of circular economy principles into wastewater treatment through the innovative use of recycled Ti-6Al-4V titanium alloy electrodes. By repurposing titanium alloys from metal additive manufacturing (AM) waste, the research aims to address the treatment of acidic and oil-contaminated industrial wastewater in a sustainable manner. The recycled electrodes demonstrate notable stability and fouling resistance in challenging acidic conditions, attributed to their unique surface porosity and conductive properties. Electrochemical processes, including hydrogen evolution at the cathode, facilitate metal ion precipitation and destabilize surfactant-stabilized oil droplets. Cyclic voltammetry and long-term stability tests highlight the electrodes’ resilience, providing an …

Development Of A Surface-Mounted Strong Post For The Midwest Guardrail System, Gnyarienn Selva Kumar

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This research investigated the development of a surface-mounted strong post for the Midwest Guardrail System (MGS), designed to replicate the behavior of the standard MGS post, a W6 x8.5, 72-in. long post embedded 40 in. into strong soil. The MGS is a strong post, W-beam guardrail system that has been successfully evaluated in many applications using crashworthiness criteria described in the American Association of State Highway and Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH). However, in some locations, conventional soil-embedded posts are impossible to install due to subgrade obstructions like concrete slabs, mow strips, utilities, and limited right-of-way. …

Polarimetry Terahertz Imaging Of Human Breast Cancer Surgical Specimens, Nikita Gurjar, Keith Bailey, Magda O. El-Shenawee

Electrical Engineering and Computer Science Faculty Publications and Presentations

Purpose

We investigate terahertz (THz) polarimetry imaging of seven human breast cancer surgical specimens. The goal is to enhance image contrast between adjacent tissue types of cancer, healthy collagen, and fat in excised breast tumors. Based on the biological perception of random growth of cancer and invasion of surrounding healthy tissues in the breast, we hypothesize that cancerous cells interact with the THz electric field in a different manner compared with healthy cells. This difference can be best captured using multiple polarizations instead of single polarization.

Approach

Time domain pulsed signals are experimentally collected from each pixel of the specimen …

Prevalence Of Autism Spectrum Characteristics In Students Taking Undergraduate Computing Courses, Rachel Michaela Mettenbrink

School of Computing: Dissertations, Theses, and Student Research

The incidence rate of autism spectrum condition (ASC) has increased significantly in recent decades, as awareness of the condition and its impacts increases amongst clinicians, parents, and the general population. Medical literature has proposed that there may be a relationship between ASC and participation in the computing field. This study tests for the prevalence of autism spectrum condition traits measured by delivering the Autism Spectrum Quotient (AQ) to a population of undergraduate computer science students. We examine the relationships between AQ scores and students taking undergraduate computer science classes, sex, socioeconomic status, and parents in the computing industry. Additionally, we …

Exploring Variably Saturated Flow Formulations For Modflow: Implementing A Fully 3d Richards' Equation In Modflow 6, Sebastian Vazquez-Gasty

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

This thesis explores the implementation of a fully 3D Richards’ equation solution into MODFLOW 6 to solve for saturated/unsaturated flow. Currently, MODFLOW 6 has limited capability for solving unsaturated zone flow problems by using the Unsaturated Zone Flow (UZF) package, which neglects capillarity and assumes vertical 1-dimensional flow. Various formulations of the Richards’ equation were first evaluated for their strengths and weaknesses. Various numerical solution approaches to Richards’ equation were also studied to understand the robustness and efficiency of different approaches and to select one that would best fit into the MODFLOW 6 framework. The MODFLOW 6 framework was also …

Self-Regulated Learning Through Self-Concordant Goals, Social Modeling And Sustainability Focus, Oana Mandrutiu-Iancu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Research has shown that when students spend time reflecting and autonomously selecting their college goals, they show high intrinsic motivation, low extrinsic motivation and improvement in emotional and social adjustment over the first several months of college. Despite of this, it is estimated that 77% of first- and second-year students are undecided on their major and many remain undecided as they transition into their junior and senior year. Moreover, in education settings the primary emphasis is on academic success, but focusing solely on academic goals is limiting. As learning is inherently social, academic and social domains cannot be separated, while …

Harmonizing Vaccine And Infrastructure Development To Tame Cholera Outbreaks Across Africa, Amira Mohamed Taha, Hussam Mahmoud, Emad M. Hassan, Mohamed M. Ghonaim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Vaccines and clean water shortages continue to give rise to cholera outbreaks in Africa. Coordinated efforts to increase vaccine distribution and improve physical infrastructure are needed while considering future outbreaks and water demands due to conflicts and climate events.

Examining The Adoption Of Digital Transformation Initiatives In Higher Education Institutions: A Mixed-Methods Investigation Of Employee Perceptions And Decision-Making Processes, Donald Behneman

Masters Theses and Doctoral Dissertations

Digital transformation refers to the strategic integration of innovative technologies, which include mobile devices, artificial intelligence, and cloud computing, to name a few. These digital technologies weave into business processes to drastically enhance and ultimately improve the customer experience, optimize operational efficiency, or forge new revenue streams (Beach, 2021). This mixed-methods study investigated the dynamics of digital transformation in higher education from the perspective of information technology professionals. There were four primary research questions: • Research Question 1 (RQ1): Does one or more demographic factor predict an employee’s level of decision-making in higher education as it relates to digital transformation? …

Impact Of Electrical Testing Strategies On The Performance Metrics Of Bio-Organic-Based Resistive Switching Memory, Muhammad Awais, Hao Zhe Leong, Nadras Othman, Mohamad Danial Shafiq, Feng Zhao, Kuan Yew Cheong

Electrical and Computer Engineering Faculty Research & Creative Works

Resistive Random-Access Memory (ReRAM) is considered as one of the most promising non-volatile memory technologies because of its high scalability, fast switching speed, and low power consumption. While many review papers are focused on investigating material types, material properties, device fabrication methods, and device structures, the influence of electrical testing strategies on ReRAM performance has yet been reviewed, particularly for bio-organic-based ReRAM. This review compiled, analyzed, and discussed how compliance current, voltage sweep rate, voltage sweep range, and voltage sweeping direction affect the ON/OFF ratio, read memory window, and both SET and RESET voltages of ReRAM.

I Gather The Fawns, Kelly Facenda

Gandy Dancer Archives

No abstract provided.

Msw Portfolio: Education, Application, Reflection, And Growth, Catherine Ristvedt Keller

Graduate Student Portfolios, Professional Papers, and Capstone Projects

Exploring and the social work competencies, values, and dimensions of practice. Defining and moving past positionality. Applying social work ethics, skills, and tools, and exploring how the Independent Living approach can influence the medical model for improved patient outcomes.

Buried Pipeline Performance Under Surface Loading Using Finite Eelement Analyses And Innovative Soil Box Testing Methodologies., Adam Gabreil Cantrell

Electronic Theses and Dissertations

Buried pipelines are used extensively in the utility industry to deliver natural gas to customers. Reasonable estimates indicated that there are approximately 26,000,000 miles of pipeline, of various diameters throughout the United States (PHMSA, 2018). For protection, and to relieve urban congestion, these pipelines are nearly always buried under ground. After the pipes are installed, however, there is little opportunity for inspection, or for supplemental protection, when needed. Thus, to reduce the likelihood of rupturing a natural gas pipeline, design guidelines that ensure consistent, minimum protection of these utilities, have been developed and implemented. Pipeline design and installation regulations for …

Elevator Music., Lillian Caroline Reed

Electronic Theses and Dissertations

A spy, doctor, engineer, and businessman find themselves trapped in a malfunctioning elevator in a contemporary, humorous take on Sartre's No Exit. Are these four, who come to despise each other, gathered here by chance? Is this eternal elevator ride some sort of divine punishment?

Is this hell?

Greek Key-Inspired Fractal Metamaterials With Enhanced Flexibility And Energy Absorption., Zhennan Zhang

Electronic Theses and Dissertations

Architected materials with intricate three-dimensional (3D) geometries offer unique properties and functionalities but face challenges in manufacturing costs and complexity. This research explores the integration of simple 2D Greek Key-inspired lattices into fractal designs to achieve exceptional mechanical performance. Using 3D printing and kerfing, these fractal structures demonstrate enhanced flexibility and energy absorption capabilities. Through three-point bending and in-plane tensile tests, the 2D fractal lattices exhibited a 600-fold reduction in bending force and a tensile stretch capacity of up to 520%, significantly outperforming brittle parent materials. Out-of-plane compression tests revealed a five-fold increase in energy absorption compared to honeycomb structures, …

Exploratory Learning In Two Modalities: Tabular Vs Graphical., Lianda Velic

Electronic Theses and Dissertations

In traditional educational settings, an instructor delivers a lecture prior to providing students a practice activity. Exploratory learning reverses this order to encourage active learning and engagement, typically improving learning outcomes. However, more research is needed in order to determine how to optimally design exploratory learning materials, and how differences in such design impact learning processes and outcomes. The current study investigated the impact of instructional order and activity modality type (tabular or graphical) on learning outcomes. Undergraduate students (N=252) were taught the statistical concept of consistency and the formula to compute standard deviation. In the instruct-first condition, …

Victims Unknown: An Evaluation Of The Way Louisville, Kentucky Communicated About Aids At The End Of The 20th Century, Alexander M. Vernon

Electronic Theses and Dissertations

This is thesis examines the way that printed news sources reported on AIDS during the height of the epidemic in Louisville, Kentucky. It compares between mainstream and grass-roots sources to work to identify shortcomings in reporting, and how reporting on a public health crisis can be improved upon in the future. It uses an intersectional framework to deconstruct why certain news sources reported on specific demographics of the population, across racialized and gendered lines. Chapter One analyzes the epidemic and then contextualizes the language that was used. Chapter Two focuses on mainstream local newspapers, while also defining demographics of AIDS …