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Full-Text Articles in Physical Sciences and Mathematics

Effectiveness Of Urban Composting And Waste Management In The San Francisco Bay Area, Elijah Ashiagbor May 2025

Effectiveness Of Urban Composting And Waste Management In The San Francisco Bay Area, Elijah Ashiagbor

Master's Projects and Capstones

The increasing food waste epidemic contributes to environmental degradation through amplified GHG emissions, notably CH4, from MSW landfills. Addressing this challenge is essential for public health and environmental sustainability. This research reviews municipal composting initiatives within the San Francisco Bay Area, evaluating effectiveness, efficiency, and sustainability. Utilizing data from CalRecycle and local municipalities, this study analyzes different composting processes, regulatory compliance with California’s Senate Bill 1383, and factors affecting waste diversion rates. Key discoveries indicate that in-vessel composting shows better efficiency and compost quality compared to windrow methods, particularly suitable for urban counties with space limitations. However, participation rates in …


Analyzing Ballast Water Treatments, Invasive Species, And Pathogens, And A Decade-Long Analysis On The San Francisco And Baltimore Ports, Jasmin Ibarra-Cortes May 2025

Analyzing Ballast Water Treatments, Invasive Species, And Pathogens, And A Decade-Long Analysis On The San Francisco And Baltimore Ports, Jasmin Ibarra-Cortes

Master's Projects and Capstones

Installation of advanced technologies to treat ballast water on ships is necessary to meet current ballast water management standards and reduce the secondary spread of invasive species during intracoastal voyages. This research includes a literature review on non-native aquatic species, particularly diapausing eggs, and available treatment methods for installation. A comparative analysis from 2014 - 2024 on bulker, tanker, and container vessels arriving coastwise to the ports of San Francisco and Baltimore was performed to evaluate treatment installation trends, traffic patterns, and the effectiveness of treatment(s) on targeting diapausing eggs. Use of ultraviolet (UV) radiation combined with filtration has increased …


Fe/Co/Ni-Doped Mos2 An Electrocatalyst For Overall Water Splitting, Himanshi Lnu May 2025

Fe/Co/Ni-Doped Mos2 An Electrocatalyst For Overall Water Splitting, Himanshi Lnu

Electronic Theses & Dissertations

Electrochemical water splitting is a promising method for sustainable hydrogen production, addressing global energy challenges. However, its practical application is limited by the need for efficient and durable electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). In this study, MoS₂ was doped with Co, Ni, and Fe at varying concentrations (5:0.5, 5:1, and 5:1.5) using a hydrothermal synthesis method to evaluate their potential as electrocatalysts for water splitting. Characterization revealed that metal doping significantly altered the electronic and morphological properties of MoS₂, enhancing its catalytic performance. Electrochemical evaluations in alkaline media demonstrated that Co-doped MoS₂ …


Trade-Off Between Limonene & Geraniol-Based Reprocessable And Non-Reprocessable Epoxy Thermosets: Role Of Aliphatic Diamines In Polymer Networks Design, Priyankkumar Kanubhai Patel May 2025

Trade-Off Between Limonene & Geraniol-Based Reprocessable And Non-Reprocessable Epoxy Thermosets: Role Of Aliphatic Diamines In Polymer Networks Design, Priyankkumar Kanubhai Patel

Electronic Theses & Dissertations

The growing demand for sustainable materials, driven by environmental concerns and the rapid depletion of fossil fuels, has garnered significant attention in the fabrication of bio-based epoxy thermosets as renewable alternatives to petroleum-derived thermosetting polymers. The present study focuses on the synthesis and characterization of epoxy prepolymer resins derived from limonene and geraniol via a two-step process, followed by the fabrication of thermally cross-linked flexible epoxy thermoset films using various traditional aliphatic diamine curing agents, namely 1,2-ethylenediamine (EDA), 1,4-butylenediamine (BDA), and 1,6-hexamethylenediamine (HDA). Additionally, the incorporation of cystamine, a disulfide-containing diamine, enabled the formation of a covalent adaptable network through …


Bio-Based Composites With Enhanced Mechanical Strength And Flame Retardancy, Riya Patel May 2025

Bio-Based Composites With Enhanced Mechanical Strength And Flame Retardancy, Riya Patel

Electronic Theses & Dissertations

Composites are versatile and useful in many fields, including aerospace, automotive, construction, and healthcare, due to their high mechanical strength. It is common practice to synthesize these materials using petroleum-based chemicals. Nonetheless, in the twenty-first century, scientists are more interested in using renewable resources to create composites. The greatest substitute for petroleum-based chemicals is vegetable oil. It has unsaturated double bonds that are modifiable chemically. In the present study, bio-polyol was synthesized using castor oil, an inedible vegetable oil. A ring-opening process was used to modify it and produce castor oil-based polyol. The synthesized castor oil-based polyol was characterized by …


Aerial Robotic Studies Of Volcanic Co2 Emissions, John Ericksen May 2025

Aerial Robotic Studies Of Volcanic Co2 Emissions, John Ericksen

Computer Science ETDs

Volcanic systems are inherently complex, involving dynamic interactions among magma flow, gas emissions, and atmospheric dispersion. This dissertation focuses on developing and analyzing autonomous UAS algorithms for efficiently surveying volcanic CO2 plumes, introducing several novel methods: the LoCUS algorithm, a swarm coordination and self-healing algorithm that supports gradient-based plume tracking, a transect-based technique that employs a 2D Gaussian fit to calculate CO2 plume flux, and the Sketch algorithm for rapid plume boundary tracing. By treating multiple UAS as a single scientific instrument, these methods leverage swarm algorithms to use in-situ data in ways impossible with individual drones. Validated through simulations …


Enhancing Water Supply Resilience & Sustainability: Potential Solutions To Address Water Scarcity In Bogotá, Colombia, Sophia Alvarez Wong May 2025

Enhancing Water Supply Resilience & Sustainability: Potential Solutions To Address Water Scarcity In Bogotá, Colombia, Sophia Alvarez Wong

Master's Projects and Capstones

Municipal water utilities are in urgent need of adapting to the intensifying impacts of climate change and population growth—key drivers of urban water scarcity worldwide. In rapidly expanding cities like Bogota, Colombia, these pressures have contributed to a severe water crisis driven by prolonged droughts, ecosystem degradation, increasing water demands, and overdependence on limited water sources. This study explores potential adaptation and management strategies that utilities can implement to sustainably strengthen supply system resilience and enhance water security, in the context of low- to middle-income regions. A series of comparative and case study analyses were conducted to assess the feasibility …


An Investigation Into The Inclusivity, Methodology, And Education Of Severe Weather In K-12 Schools, Stephen Holden Wooten May 2025

An Investigation Into The Inclusivity, Methodology, And Education Of Severe Weather In K-12 Schools, Stephen Holden Wooten

Theses and Dissertations

Schools are a focal point in the lives of everyone in the community, especially teachers, parents, and students. Investigating the connection between these individuals and tornadoes by identifying shortcomings in education, training, and emergency procedures can induce more effective and informed decision-making for future encounters. This study evaluated the inclusivity of tornado protocols for students with disabilities, uncovered where parents prefer their child to shelter in early dismissal situations and clarified how extensively natural hazard education and tornado drills are covered in schools. Two surveys and semi-structured interviews were used to obtain responses from earth science teachers, K-12 guardians, and …


06.16.2025 Ored Connect, Liz Williamson May 2025

06.16.2025 Ored Connect, Liz Williamson

ORED Newsletter

Email address Matters with SPAN and ARC Forms

Participant Support Costs training for PIs available in Blackboard


First Annual Advances In Business Education Conference 2025 Proceedings, Kelsey Metz, Joshua Ray May 2025

First Annual Advances In Business Education Conference 2025 Proceedings, Kelsey Metz, Joshua Ray

Advances in Business Education (ABE) Conference Proceedings

Conference Overview: The First Annual Advances in Business Education (ABE) Conference was held on May 16, 2025, at Lincoln Memorial University in Harrogate, Tennessee. Hosted by the LMU School of Business, the ABE Conference was established to promote teaching excellence through innovation and collaboration in business education. With a focus on fostering meaningful dialogue among educators, researchers, and students, the conference welcomed participants from across disciplines and institutions. The event was structured around three key tracks:

Pedagogy & Teaching Excellence: Showcasing innovative teaching methods and strategies for enhancing student learning and engagement.

Business Research: Presenting research focused on advancing knowledge …


California Kelp Forests: An Analysis Of Macrocystis Pyrifera And Nereocystis Luetkeana Restoration After Decades Of Decline, Gabrielle K. Farrer May 2025

California Kelp Forests: An Analysis Of Macrocystis Pyrifera And Nereocystis Luetkeana Restoration After Decades Of Decline, Gabrielle K. Farrer

Master's Projects and Capstones

California’s kelp forests are some of the most biodiverse and productive ecosystems on the planet. Centuries of anthropogenic degradation via habitat destruction and climate change have culminated in decreased kelp forest habitat at an accelerated rate since at least the 1850s (Scarborough et al. 2022; Rogers-Bennett & Catton, 2019; Kumagai et al. 2024; Smith et al. 2023). This study synthesizes major threats, past and present, to California’s kelp forests, including the overharvesting of multiple species, pollution from coastal development, and climate change impacts. I also examine current management practices regarding kelp forests such as the use of marine protected areas …


A Roadmap For Greywater Reuse At The University Of San Francisco Hilltop Campus: A Financial, Regulatory, And Technical Feasibility Study, Apama'bo Anand Oszkar May 2025

A Roadmap For Greywater Reuse At The University Of San Francisco Hilltop Campus: A Financial, Regulatory, And Technical Feasibility Study, Apama'bo Anand Oszkar

Master's Projects and Capstones

Abstract

Water scarcity is increasing in California, so we need strategies to reduce potable water demand. Decentralized greywater systems offer promising solutions to this problem. This study provides a roadmap for successfully implementing greywater reuse at the University of San Francisco (USF) by addressing financial, technical, and regulatory considerations. By deploying a mixed-methods approach that combines qualitative expert interviews and quantitative water usage analysis, policy review, cost analysis, and case studies, this study established USF’s annual recycled water demand as 8 million gallons, with two primary uses: irrigation, which accounts for 67% of the demand, and toilet-urinal flushing, which represents …


Butte Priority Soils Operable Unit (Bpsou)2020 Consent Decree Appendix D Attachment C Sections 7 And 8 Discrepancies, Mike Mcanulty May 2025

Butte Priority Soils Operable Unit (Bpsou)2020 Consent Decree Appendix D Attachment C Sections 7 And 8 Discrepancies, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Re: Comment Letter For Butte Priority Soils Operable Unit (Bpsou) Principles For A Greener Cleanup Report (Dated December 23, 2024), Emma Rott May 2025

Re: Comment Letter For Butte Priority Soils Operable Unit (Bpsou) Principles For A Greener Cleanup Report (Dated December 23, 2024), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Global Attractivity Of Positive Solutions Of Higher Order Nonlinear Difference Equations And Its Applications, Abdulaziz Almaslokh May 2025

Global Attractivity Of Positive Solutions Of Higher Order Nonlinear Difference Equations And Its Applications, Abdulaziz Almaslokh

Theses and Dissertations

Difference equations play an effective role in many mathematical models that represent some phenomena in different fields such as physics, economics, engineering and biology. From this perspective, studying and analyzing such equations are interesting issues for the advancement of scientific research. In particular, studying the asymptotic behavior of positive solutions of some population models that are a system of difference equations has become a necessity. In this dissertation, we examine the global attractivity of positive solutions of certain higher order nonlinear difference equations and apply these results to some population models.


Promoting Collaboration And Multi-Directional Reliance By Sharing Mental Model Information For Effective Multi-Agent Teaming, Audrey L. Aldridge May 2025

Promoting Collaboration And Multi-Directional Reliance By Sharing Mental Model Information For Effective Multi-Agent Teaming, Audrey L. Aldridge

Theses and Dissertations

Successful human-agent teaming requires teammates to form and maintain a shared or common understanding of several attributes regarding taskwork and teamwork. With enhanced information sharing, mental model development, and team functionality, teammates (human, autonomous) can learn to anticipate each others' behaviors, preferences, and needs as well as understand their capabilities and limitations. In designing a framework to support this type of cooperative teaming, there is a need to determine how sharing knowledge, mental models, and common understandings impacts teaming dynamics and performance. By incorporating each individual's understanding into a human-agent interface, this research enables better team coordination and performance through …


Real-Time Enhanced Tornado Warning Product Guidance Based On Tornado Debris Signature Height And Population Density, Alexander Cooke May 2025

Real-Time Enhanced Tornado Warning Product Guidance Based On Tornado Debris Signature Height And Population Density, Alexander Cooke

Theses and Dissertations

This research aims to develop an operational program for enhancing real-time tornado warning capabilities by integrating tornado debris signature (TDS) analysis with population impact assessment. The proposed Python-based tool will ingest Level II radar data to identify and analyze TDS, estimating tornado intensity based on maximum TDS height. For high-intensity tornadoes, the program will project the potential impact area using storm motion vectors and integrate this with population density data. The system will assess whether the situation meets National Weather Service criteria for enhanced warning products, providing forecasters with rapid, objective guidance for critical warning decisions. The program’s performance will …


Optimizing Mars Terrain Segmentation With Weakly Supervised Learning: A Focus On Weighted Loss From Annotation Metadata, Malika Dutta May 2025

Optimizing Mars Terrain Segmentation With Weakly Supervised Learning: A Focus On Weighted Loss From Annotation Metadata, Malika Dutta

Theses and Dissertations

The study of planetary surfaces heavily depends upon space rovers that gather detailed images of terrain needed for analysis and navigation. Deep neural networks and other sophisticated machine learning techniques are necessary for autonomous navigation in challenging terrain. However, the inconsistent annotations by citizen scientists frequently hinder the performance of these models. This study seeks to optimize terrain segmentation to improve the autonomous capabilities of future Mars rovers by presenting a novel weakly supervised learning framework to handle noise and unreliability in datasets. Using factors like number of clicks, pixel accuracy, and annotator dependability, the method utilizes annotation metadata in …


Application Of Pu Learning In Detection Of Ddos Attacks, Gagana Sathya Narayana Prasad May 2025

Application Of Pu Learning In Detection Of Ddos Attacks, Gagana Sathya Narayana Prasad

Theses and Dissertations

The gcore radar 2024 says, the number of DDoS attacks has been increased by 46% in 12 months. Supervised and unsupervised techniques struggle detecting DDoS attacks due to the scarcity of labeled attack samples and an overwhelming presence of benign traffic. In contrast PU- Learning offers a promising solutions by dividing the data into positive and unlabeled data. This study explores the effectiveness of PU-learning in detecting DDoS attacks by comparing it with unsupervised methods. This method employs PU Bagging, Two Step method and auto-encoder based models to extract meaningful patters from network traffic data, utilizing CICDDoS2017 dataset for evaluation. …


Evaluating Rainfall Sensitivity Over Land To Tropical Cyclone Parameters Using Idealized Wrf, Madison C. Yawn May 2025

Evaluating Rainfall Sensitivity Over Land To Tropical Cyclone Parameters Using Idealized Wrf, Madison C. Yawn

Theses and Dissertations

Tropical cyclones (TCs) are extreme weather events impacting the United States nearly every year. These events often cause severe damage due to the associated responses they produce including storm surge and rainfall, and the accurate estimation of these TC hazards is necessary to support coastal engineering, risk assessment, and emergency management activities. Evaluating TC-driven hazards is often done in combination with numerical models to simulate how environmental interactions alter the physical processes and responses of these storms. The purpose of this study was to simulate synthetic TC events using the Advanced Weather Research and Forecasting (WRF) model to understand how …


Atmospheric Turbulence Education Effects On Flight Anxiety, Megan A. Hanna May 2025

Atmospheric Turbulence Education Effects On Flight Anxiety, Megan A. Hanna

Theses and Dissertations

This study examines the effect of turbulence education on flight anxiety. A pre-post methodology measured students’ anxiety levels before and after a study abroad flight, using an educational video during the pre-flight survey to change their feelings. The Flight Anxiety Situations (FAS) questionnaire assessed anxiety at three survey points: pre-video, post-video, and post-flight. Qualitative analysis using Friedman’s test and the Wilcoxon Signed-rank test, indicated that turbulence education effectively decreased generalized and anticipatory flight anxiety, particularly in non-phobic students. Text analysis of open-ended responses suggested increased scientific knowledge post-video helped students apply technical atmospheric processes to their feelings. Turbulence education was …


Apatite Entrapment Of Iodine For Nuclear Waste Disposal Applications, William E. Laird May 2025

Apatite Entrapment Of Iodine For Nuclear Waste Disposal Applications, William E. Laird

Theses and Dissertations

The purpose of this thesis is to provide baseline knowledge of iodine incorporation into calcium phosphate minerals, specifically apatite. Iodine-129 is a fission product in Spent Nuclear Fuel (SNF) that can administer significant amounts of radiation in small quantities. Apatite (Ca10(PO4)6 (OH, F, Cl)) has been studied for the use of radionuclide confinement. Experimental design was set up to mimic temperatures expected in geologic repositories from 40 to 250℃. Experiments are broken into 2 groups based on iodine species being examined. The first group focuses on iodate (IO3-) which is prevalent under oxidized conditions, and the second handles iodide (I-) …


Cyber Security Threat Recognition And Preparedness Of Undergraduate Students, Litany Hope Lineberry May 2025

Cyber Security Threat Recognition And Preparedness Of Undergraduate Students, Litany Hope Lineberry

Theses and Dissertations

Cybersecurity awareness and preparedness are critical competencies for individuals across academic disciplines and professional sectors. However, undergraduate students often lack sufficient knowledge and skills to recognize and mitigate cybersecurity threats. This dissertation examines cybersecurity threat recognition and preparedness among undergraduate students through a three-phase research approach. Study 1 explores faculty perspectives on students' cybersecurity awareness, identifying gaps in knowledge and preparedness across various fields of study. Study 2 investigates industry professionals' perceptions of new hires’ cybersecurity readiness, assessing the alignment between academic training and industry expectations. Study 3 evaluates the effectiveness of an online intervention designed to enhance students' cybersecurity …


The Role Of Enso Diversity In Modulating Tornadic Activity In The United States, Davis Boyd Newton May 2025

The Role Of Enso Diversity In Modulating Tornadic Activity In The United States, Davis Boyd Newton

Theses and Dissertations

Tornado activity in the United States is influenced by large-scale climate patterns, especially by the El Niño-Southern Oscillation (ENSO). While prior research has explored ENSO’s impact on severe weather, the influence of ENSO flavors, Central Pacific (CP) and Eastern Pacific (EP), on tornadic activity remains understudied. Using tornado records, reanalysis data, and sea surface temperature anomalies, we assess how convective available potential energy (CAPE), wind shear, and jet stream dynamics influence tornado frequency and distribution. Results indicate that CP La Niña years had significant increases in tornado frequency, particularly across the Midwest, Central Plains, and Southeast. EP ENSO years had …


Earth Analogue Analysis Of Volcanic/Tectonic Interactions With Applications To Venusian Stresses, Michael Ortigoza May 2025

Earth Analogue Analysis Of Volcanic/Tectonic Interactions With Applications To Venusian Stresses, Michael Ortigoza

Theses and Dissertations

Venus shares many geological similarities with Earth, yet its tectonic processes and magma injection mechanisms remain poorly understood. A key question in planetary geology is how effusive volcanism persists despite the intense horizontal compression terrestrial bodies experience over time. To explore these issues, we examine the Spanish Peaks dike swarm in Colorado which serves as an ideal site for investigating magma intrusion under compressive stress conditions. Through field mapping, orientation measurements, and structural analysis, we identify a strong relationship between pre-existing joints and dike orientations, suggesting that these fractures serve as critical magma pathways in compressive regimes. Additionally, evidence of …


Establishing A Baseline For Detecting Lotl Attacks In Windows Operating Systems, Ashlyn Martin Phillips May 2025

Establishing A Baseline For Detecting Lotl Attacks In Windows Operating Systems, Ashlyn Martin Phillips

Theses and Dissertations

There has been an increasing realization of the rise in living off the land (LOTL) attacks where adversaries misuse legitimate system tools, particularly with state-sponsored actors targeting critical infrastructure in the United States. These attacks are difficult to detect because they allow attackers to remain present in a system without the user’s knowledge for an extended period. This thesis establishes an initial baseline specifically for Windows operating systems to measure normal system activity, focusing on CPU usage, memory utilization, and process activity. It particularly examines the use of PowerShell alongside other applications. The findings from this baseline are used to …


Investigations Into Fluorescence Of Fluorene Dimers: Linker Impacts And Tuning Potential Through Substituent Addition, Abigail R. Ressler May 2025

Investigations Into Fluorescence Of Fluorene Dimers: Linker Impacts And Tuning Potential Through Substituent Addition, Abigail R. Ressler

Theses and Dissertations

Fluorene-based fluorescing conjugated polymers are being used to develop sensors that show great sensitivity and selectivity, however, important questions about the photophysics of these systems remain unanswered. For example, a fluorescence intensity difference was observed between fluorene dimers linked with either an acetylene (diFA) or phenyl (diFP). The polymers diFA and diFP have similar structures and extinction coefficients, yet diFA yielded a five times higher fluorescence intensity than diFP. In project one, Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) were used to calculate the ground and excited states of diFA and diFP. A python code was developed to solve …


Integrating Case Studies With Meteorologists’ Insight: Assessing Meteorologists’ Perception And Utilization Of Composite Indices, Brianna Marie Salazar May 2025

Integrating Case Studies With Meteorologists’ Insight: Assessing Meteorologists’ Perception And Utilization Of Composite Indices, Brianna Marie Salazar

Theses and Dissertations

Meteorologists from sectors, including broadcast, academia, and operations, use derived composite indices such as 0-1km and 0-3km energy helicity index (EHI), effective-layer supercell composite parameter (SCP), fixed-layer and effective layer significant tornado parameter (STP), in addition to other resources, when developing severe local storm forecasts. This study utilizes the Weather Research and Forecasting (WRF) model to create simulations of composite indices for two tornado-producing events: 31 March 2023 and 3 May 1999. With modifications to geographical location, these simulated scenarios are then utilized in the survey to gauge how meteorologists assess where tornado potential is highest. Additionally, a combination of …


Zeroizing Trust In A Naïve Federated Zero Trust Environment, Keith E. Strandell May 2025

Zeroizing Trust In A Naïve Federated Zero Trust Environment, Keith E. Strandell

Theses and Dissertations

The position of the United States on the global stage is predicated on information dominance and the ability to project power through cooperative engagements with mission partners in both wartime and peacetime. Recent cyber-attacks highlighted the need for a more robust cybersecurity posture. As the United States progresses toward the adoption of Zero Trust, it is incumbent on the Department of Defense to assess the impact to the ability to share data across strategic partnerships while securing the data of both the United States and its partners. This paper proposes research into ensuring an environment rooted in Zero Trust and …


Synthetic Data Augmentation For Retinoblastoma Using Diffusion, Andrew Thompson May 2025

Synthetic Data Augmentation For Retinoblastoma Using Diffusion, Andrew Thompson

Theses and Dissertations

Many AI models rely on large and high quality datasets for optimal training. In certain cases, data can be difficult or expensive to obtain, making training difficult. Rare medical conditions are one of these cases. Datasets for retinoblastoma are severely lacking in quantity. Diffusion has been used to create synthetic data in the industrial, medical, and financial domains. By applying the latest Diffusion methods to retinoblastoma, this work seeks to improve predictive model performance on identifying retinoblastoma.