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Full-Text Articles in Physical Sciences and Mathematics

Edge Colored And Edge Ordered Graphs, Per Gustin Wagenius Jan 2024

Edge Colored And Edge Ordered Graphs, Per Gustin Wagenius

Graduate College Dissertations and Theses

In this work, the current state of the field of edge-colored graphs is surveyed. Anew concept of unshrinkable edge colorings is introduced which is useful for rainbow subgraph problems and interesting in its own right. This concept is analyzed in some depth. Building upon the linear edge ordering described in a recent work from Gerbner, Methuku, Nagy, Pálvölgyi, Tardos, and Vizer, edge-ordering graphs with the cyclic group is introduced and some results are given on this and a related counting problem.


Probabilistic Modeling Of Disease: Addressing Uncertainties In Within-Host And Population-Level Dynamics, Mariah Boudreau Jan 2024

Probabilistic Modeling Of Disease: Addressing Uncertainties In Within-Host And Population-Level Dynamics, Mariah Boudreau

Graduate College Dissertations and Theses

Mathematical modeling of disease dynamics provides powerful tools to understand, predict, and evaluate emerging diseases. These insights aid public health officials, along with other modelers. With a plethora of models to choose from, it is important to consider a model that encapsulates the stochastic nature of disease dynamics. Stochasticity not only conveys chances of stochastic extinction, but provides probabilistic outcomes, essential for capturing the stochastic nature of the real world. In this thesis, three stochastic models are presented, each addressing uncertainties in mechanisms and interpretation of these models, to aid other modelers and decision makers.Starting with the source of infection …


Analysis Of Ultra-Wideband Voltage Pulse Propagation On Dispersive Absorptive Transmission Lines, Katherine Aho Jan 2024

Analysis Of Ultra-Wideband Voltage Pulse Propagation On Dispersive Absorptive Transmission Lines, Katherine Aho

Graduate College Dissertations and Theses

Electromagnetic transient waves are pulsed events that occur when there is an abruptchange in the typical steady-state conditions on a transmission line. Digital pulses on integrated circuits and a lightning strike on overhead power lines are some examples of transient voltage pulses. Although transients occur within a very short time duration, they can propagate over long distances; much farther than a slowly-varying envelope signal can propagate. Lingering effects of transients can be damaging to electrical equipment if they are not properly mitigated. Despite the negative effects of transients, certain designed transient pulses may be used to an advantage in remote …


Assessing The Impact Of An Intervention To Build Food Agency During Emerging Adulthood, Amy Finley Jan 2024

Assessing The Impact Of An Intervention To Build Food Agency During Emerging Adulthood, Amy Finley

Graduate College Dissertations and Theses

Agriculture is an ancient human activity that has always changed the Earth. But the scale and scope of modern, industrialized agriculture is producing emergent problems in the food system, like unprecedented environmental degradation and high-calorie nutrient-poor diets that are driving poor health outcomes. Increasing cooking skills and the frequency of home cooking have been proposed as solutions to escalating rates of nutrition-related public health problems and may also be important to meeting diet-related sustainability goals like reducing meat consumption. Subsequently, the overarching aim of this thesis is to situate the importance of cooking as a strategy for food systems transformation, …


Unraveling Public Evacuation Likelihood: Structural Equation Models And The Extended Parallel Process Model In Focus, Molly Margaret Myers Jan 2024

Unraveling Public Evacuation Likelihood: Structural Equation Models And The Extended Parallel Process Model In Focus, Molly Margaret Myers

Graduate College Dissertations and Theses

This study explores the intricate relationships between risk perception, efficacy appraisal, and evacuation likelihood in the context of flooding among the United States public. The Extended Parallel Process Model (EPPM) developed by Witte (1992) serves as the theoretical framework for this study, emphasizing the two-pronged appraisal process of threat and efficacy, influencing individual responses to risk messaging. Analysis of the data delves into the relationships between risk perception and evacuation likelihood, offering insights into the public's understanding of flood risk and readiness for impending flood events. This study used Structural Equation Modeling (SEM) to discern the impact of threat and …


Ring Learning With Errors, Sarah Days-Merrill Jan 2024

Ring Learning With Errors, Sarah Days-Merrill

Graduate College Dissertations and Theses

Over the last twenty years, lattice-based cryptosystems have gained interest due to their levelof security against attacks from quantum computers. The main cryptosystems are based on the hardness of Ring Learning with Errors (RLWE). The Learning with Errors (LWE) problems were first introduced in 2005 by Regev [Reg09] and in 2010, [LPR10] developed the Ring Learning with Errors (RLWE) problems as candidates for safe encryption against quantum computers. Let K be a number field with ring of integers OK. For a prime q, the RLWE problems rely on samples of the form (a, b) ∈ OK/qOK × OK/qOK where a …


Capacitive Voltage Converter Method For The Search Of Water Ice On Celestial Bodies, Nathan Raymond Jan 2024

Capacitive Voltage Converter Method For The Search Of Water Ice On Celestial Bodies, Nathan Raymond

Graduate College Dissertations and Theses

Electrical Capacitance Tomography (ECT) is an advanced imaging technique used to map the permittivity of dielectric materials. ECT has diverse uses across various engineering fields, including industrial pipelines, the oil and gas sector, chemical manufacturing, and process monitoring, particularly for analyzing fluid flows. ECT can also be applied as a form of dielectric spectroscopy by measuring the response of materials under test (MUT) to changes in frequency, allowing for a detailed study of permittivity variations in a medium.One of NASA's Artemis missions is to locate and utilize in-situ resources. Transporting water to space is prohibitively expensive, with costs of $20,000 …


Nesting Habitat Selection And Management Of Three Freshwater Turtle Species Along The Shorelines Of Lake Champlain, Destini Acosta Jan 2024

Nesting Habitat Selection And Management Of Three Freshwater Turtle Species Along The Shorelines Of Lake Champlain, Destini Acosta

Graduate College Dissertations and Theses

Habitat loss, caused by factors like urbanization and land conversion, disrupts ecosystems and can lead to population declines and even extinctions of species that rely on those habitats for survival. Loss of shoreline habitat has been widespread and reduces nesting grounds for species like freshwater turtles, often threatening their reproductive success and population viability. In the Lake Champlain Basin, several turtle species have experienced declines and recovery efforts are limited by a lack of information on habitats selected during the crucial period of nesting. This study aimed to identify and characterize nesting habitat selection of freshwater turtles and included two …


Organic Fouling Mitigation In Forward Osmosis Technology Through The Use Of Oscilatting Alternating Current Electric Fields, Logan Werner Jan 2024

Organic Fouling Mitigation In Forward Osmosis Technology Through The Use Of Oscilatting Alternating Current Electric Fields, Logan Werner

Graduate College Dissertations and Theses

Forward osmosis (FO) is the term given to osmosis in water filtration applications. FO has many advantages to conventional membrane filtration processes. The lack of external pressure needed to force solvent through the membrane is dramatically decreased in FO, resulting in a lower cost of operation compared to reverse osmosis. Lower external pressures also result in decreased fouling on the membrane surface and improved permeate flux. Fouling is one of the foremost challenges within the membrane filtration industry and is one of the biggest contributors to operating costs. While FO results in less fouling than RO, fouling remains a major …


Employing Genetic Algorithms For Energy-Efficient Data Routing In Internet Of Things Networks, Farzana Akhter Jan 2024

Employing Genetic Algorithms For Energy-Efficient Data Routing In Internet Of Things Networks, Farzana Akhter

Graduate College Dissertations and Theses

The Internet of Things (IoT) connects a vast number of smart objects for various applications,such as home automation, industrial control, and healthcare. The rapid advancement in wireless technologies and miniature embedded devices has enabled IoT systems to be deployed in various environments. However, the performance of IoT devices is limited because of the imbalance of data traffic on different router nodes. Nodes that experience high data volume will have a higher energy depletion rate and, as a result, will reach the end of their life quicker than other routers that have less data traffic. Genetic Algorithms are a well-known technique …


Investigating The Effect Of Relative Humidity On Organic New Particle Formation From The Dark Ozonolysis Of Biogenic Volatile Organic Compounds, Austin Callum Flueckiger Jan 2024

Investigating The Effect Of Relative Humidity On Organic New Particle Formation From The Dark Ozonolysis Of Biogenic Volatile Organic Compounds, Austin Callum Flueckiger

Graduate College Dissertations and Theses

Solid or liquid particulate matter suspended in the air, also known as atmospheric aerosols, are a ubiquitous component of Earth’s atmosphere. It is important to understand the chemical and physical processes that lead to the formation of these aerosols as they have an impact on climate health and human health. An important subset of atmospheric aerosols are secondary organic aerosols (SOA) that form from the gas-phase oxidation of volatile organic compounds (VOCs). VOCs can be emitted via biogenic and anthropogenic pathways, however, global estimates place biogenic sources as the major contributor. Although widely studied, some of the fundamental mechanisms that …


Computing The Canonical Ring Of Certain Stacks, Jesse Franklin Jan 2024

Computing The Canonical Ring Of Certain Stacks, Jesse Franklin

Graduate College Dissertations and Theses

We compute the canonical ring of some stacks. We first give a detailed account of what this problem means including several proofs of a famous historical example. The main body of work of this thesis expands on our article \cite{Franklin-geometry-Drinfeld-modular-forms} in describing the geometry of Drinfeld modular forms as sections of a specified line bundle on a certain stacky modular curve. As a consequence of that geometry, we provide a program: one can compute the (log) canonical ring of a stacky curve to determine generators and relations for an algebra of Drinfeld modular forms, answering a problem posed by Gekeler …


Role Of Relative Humidity In New Particle Formation From Ozonlysis Of Atmospheric Volatile Organic Compounds, Christopher Snyder Jan 2024

Role Of Relative Humidity In New Particle Formation From Ozonlysis Of Atmospheric Volatile Organic Compounds, Christopher Snyder

Graduate College Dissertations and Theses

The impact of relative humidity (RH) on organic new particle formation (NPF) from ozonolysis of biogenic volatile organic compounds (BVOCs) remains an area of active debate. Previous reports provide contradictory results indicating both depression and enhancement of NPF under conditions of moderate RH, while others ignore the potential impact. Only several reports have suggested that the effect may depend on absolute mixing ratio of the precursor volatile organic compound (VOC, ppbv). However, before any experiments could be completed, development of new methods was necessary to overcome the limitation of sampling ultrafine nanoparticles (<50 nm aerodynamic diameter) with aerosol mass spectrometry. This dissertation includes a report on a new Particle Growth Apparatus (PaGA) that artificially grows particles from as small as 17 nm to over 110nm. Considerable effort was made to identify the most suitable growth matrix (squalane) and optimize particle growth for reproducibility and sensitivity.

The PaGA was then utilized in the …


Community Science And Coyote Stories: Capturing And Communicating Nature's Non-Material Values For Use In Decision-Making, Joshua Wright Morse Jan 2024

Community Science And Coyote Stories: Capturing And Communicating Nature's Non-Material Values For Use In Decision-Making, Joshua Wright Morse

Graduate College Dissertations and Theses

The reasons and ways that nature matters underlie every part of environmental decision-making. Yet, there are disparities in how different kinds of benefits from and values about nature are represented in policy and practice. This dissertation explores how decision-makers and community members value nature broadly and also in the context of a specific human-wildlife interaction in Vermont, United States.

In my first chapter, I conduct semi-structured interviews with environmental sector practitioners in Vermont to learn about their awareness of non-material values from nature. I find that practitioners talk readily about both material and non-material ecosystem services as well as multiple …


Entrepreneurial Behavior, Technology Adoption, And Climate Change Resilience: Evidence From Small And Medium-Scale Livestock And Maple Producers In Vermont, Dimagi Pitawala Jan 2024

Entrepreneurial Behavior, Technology Adoption, And Climate Change Resilience: Evidence From Small And Medium-Scale Livestock And Maple Producers In Vermont, Dimagi Pitawala

Graduate College Dissertations and Theses

Agriculture, particularly livestock and maple production, is at the core of Vermont’s identity, landscape, and economy. Although Vermont is famous for its unique small farms and exceptional maple syrup, more recently it has become known as one of the fastest-warming states in the United States, threatening the viability of the state’s vibrant agricultural sector. In addition to climate change, increasing farm consolidation, low farmgate prices, market competition, and changing consumer demands and lifestyles have begun to affect the viability of small and medium-scale livestock farms and maple operations. While numerous policies and programs seek to ensure the viability of these …


Building A Kinder Super Highway: Online Group Behavior Driven By Platform Design And Social Policy, Milo Trujillo Jan 2024

Building A Kinder Super Highway: Online Group Behavior Driven By Platform Design And Social Policy, Milo Trujillo

Graduate College Dissertations and Theses

Much of human socialization occurs online, and is mediated by telecommunicationsplatforms, particularly social media. These platforms both facilitate and restrict interaction in two ways: first, through the technical affordances they offer, such as conversation trees or direct messages or community self-moderation and voting; and second, through social policy, particularly regarding what content is permissible on a platform and how infractions are penalized. My work engages with platform influence over group social behavior through a series of case studies and through introducing purpose-built methodology.

I begin by examining the influence GitHub exhibits over open-source software de-velopment by contrasting the development practices …


A Computational Journey Through Conspiracy Theories: A Genealogical Approach, Mohsen Ghasemizade Jan 2024

A Computational Journey Through Conspiracy Theories: A Genealogical Approach, Mohsen Ghasemizade

Graduate College Dissertations and Theses

In an era where misinformation and conspiracy theories (CTs) proliferate, this study presents an approach to understanding and categorizing CTs through the development of a detailed `family tree'. By adopting different definitions, we explore CTs as efforts to explain events through the lens of hidden, malevolent forces, distinguishing between actual conspiracies and theoretical beliefs without empirical proof. Leveraging an analysis of 1769 articles from fact-checking websites and employing Keyphrase Extraction, we compiled a dataset that led to the identification of 769 unique conspiracies. A RoBERTa-based binary classifier was developed, achieving an F1 score of 87\%, to distinguish CTs from non-CT …


Effective Drag Coefficient Prediction On Single-View 2d Images Of Snowflakes, Cameron Hudson Jan 2024

Effective Drag Coefficient Prediction On Single-View 2d Images Of Snowflakes, Cameron Hudson

Graduate College Dissertations and Theses

The drag coefficient of snowflakes is an crucial particle descriptor that can quantify the relationships with the mass, shape, size, and fall speed of snowflake particles. Previous studies has relied on estimating and improving empirical correlations for the drag coefficient of particles, utilizing 3D images from the Multi-Angled Snowflake Camera Database (MASCDB) to estimate snowflake properties such as mass, geometry, shape classification, and rimming degree. However, predictions of the drag coefficient with single-view 2D images of snowflakes has proven to be a challenging problem, primarily due to the lack of data and time-consuming, expensive methods used to estimate snowflake shape …


Robust Interventions In Network Epidemiology, Erik Weis Jan 2024

Robust Interventions In Network Epidemiology, Erik Weis

Graduate College Dissertations and Theses

Which individual should we vaccinate to minimize the spread of a disease? Designing optimal interventions of this kind can be formalized as an optimization problem on networks, in which we have to select a budgeted number of dynamically important nodes to receive treatment that optimizes a dynamical outcome. Describing this optimization problem requires specifying the network, a model of the dynamics, and an objective for the outcome of the dynamics. In real-world contexts, these inputs are vulnerable to misspecification---the network and dynamics must be inferred from data, and the decision-maker must operationalize some (potentially abstract) goal into a mathematical objective …


Investigations Of Low-Frequency Vibrations In Crystalline Organic Semiconductors And Their Impact On Material Properties, Peter Alexander Banks Jan 2023

Investigations Of Low-Frequency Vibrations In Crystalline Organic Semiconductors And Their Impact On Material Properties, Peter Alexander Banks

Graduate College Dissertations and Theses

An increasing amount of attention has been dedicated to small-molecule based crystalline organic semiconducting materials, with regular reports of newly-designed molecules that are specifically engineered to produce high-performance organic devices. Commonly, these molecules contain distinct chemical characteristics that are specifically incorporated to inhibit the large-amplitude, low-frequency vibrational motions that occur about intermolecular van der Waals contacts. These molecular motions have been historically considered a primary factor that uniquely limits the semiconducting performance of these materials, as the large displacements induced by these vibrations strongly diminish the electronic coupling between molecules in the lattice. This phenomenon is denoted as electron-phonon coupling, …


Data-Driven Reachability Of Non-Linear Systems Via Optimization Of Chen-Fliess Series, Ivan Perez Avellaneda Jan 2023

Data-Driven Reachability Of Non-Linear Systems Via Optimization Of Chen-Fliess Series, Ivan Perez Avellaneda

Graduate College Dissertations and Theses

A reachable set is the set of all possible states produced by applying a set of inputs, initial states, and parameters. The fundamental problem of reachability is checking if a set of states is reached provided a set of inputs, initial states, and parameters, typically, in a finite time. In the engineering field, reachability analysis is used to test the guarantees of the operation’s safety of a system. In the present work, the reachability analysis of nonlinear control affine systems is studied by means of the Chen-Fliess series. Different perspectives for addressing the reachability problem, such as interval arithmetic, mixed-monotonicity, …


Developing Muscle Synergy Functions For Remote Gait Analysis, Nicole Marie Donahue Jan 2023

Developing Muscle Synergy Functions For Remote Gait Analysis, Nicole Marie Donahue

Graduate College Dissertations and Theses

Digital medicine promises to improve healthcare and enable its delivery to rural and underserved communities. A key component of digital medicine is accurate and robust remote patient monitoring. For example, remote monitoring of biomechanical measures of limb impairment during daily life could allow near real-time tracking of rehabilitation progress and personalization of rehabilitation paradigms in those recovering from orthopedic surgery. Wearable sensors have long been suggested as a means for quantifying muscle and joint loading, which can provide a direct measure of limb impairment. However, current approaches either do not provide these measures or require unwieldy wearable sensor arrays and/or …


Forest Management Tradeoffs: Examining Relationships Between Timber Harvest, Carbon Sequestration And Storage, Bioenergy, And Wildlife, Michelle L. Brown Jan 2023

Forest Management Tradeoffs: Examining Relationships Between Timber Harvest, Carbon Sequestration And Storage, Bioenergy, And Wildlife, Michelle L. Brown

Graduate College Dissertations and Theses

Timber harvesting is the leading cause of adult tree mortality in forests of the northeastern United States. While current rates of harvest are generally sustainable, there is considerable pressure to increase harvest to meet timber production, climate, and energy goals. Maximizing one of these values may compromise other forest resources, including a wide range of ecosystem services and the conservation of native species. This dissertation investigates the effects of timber harvest on carbon sequestration and storage, bioenergy, and wildlife. First, I estimated current harvest regimes for different forest types and regions across the U.S. states of New York, Vermont, New …


Timeseries Analysis To Characterize Complex Phenomena In Environmental And Human Health Applications, Jeremy Ernest Matt Jan 2023

Timeseries Analysis To Characterize Complex Phenomena In Environmental And Human Health Applications, Jeremy Ernest Matt

Graduate College Dissertations and Theses

Studying and evaluating time series signals that emerge when monitoring complex phenomena requires fusing, visualizing, and often reducing the dimensionality of large amounts of data to reveal the patterns and relationships that appear at different scales. In this work, we develop methods for monitoring, visualizing, and identifying the complex relationships that appear in time series data collected from two very different domains – health care conversations and river networks – to facilitate large-scale understanding of these systems. Fostering connection between clinicians and patients and their families in the context of serious illness is a fundamental component of good clinical communication …


An Analysis Of A Linear Algebra Based Group Key Exchange Protocol, Annie Zhang Jan 2023

An Analysis Of A Linear Algebra Based Group Key Exchange Protocol, Annie Zhang

Graduate College Dissertations and Theses

Group key exchange protocols are used to establish session keys, which can then be used as encryption keys to set up secure channels of communication, between more than two parties simultaneously. Many different group key exchange protocols exist and require security proofs in order to determine the strength of the protocol and answer the following questions: does the protocol provide authentication, and if so, to what degree? Does the protocol provide key secrecy? In this thesis we examine a particular group key exchange protocol that we call the \textit{vector space projection protocol} as first described in “A Group Key Establishment …


Paleolimnological Data Synthesis To Assess Long-Term Ecological Change In Vermont Lakes, Ismar Biberovic Jan 2023

Paleolimnological Data Synthesis To Assess Long-Term Ecological Change In Vermont Lakes, Ismar Biberovic

Graduate College Dissertations and Theses

Lakes are excellent early indicators of environmental change on a landscape scale. Due to their connectedness in the landscape, any alteration of land-cover extends beyond a single watershed and can only be amplified by the effects of climate change. These processes can reflect differently across lakes of various characteristics, however, combined, they can leave a lasting impact on biogeochemical processes of a lake, resulting in profound effects on biological communities residing in it. Lake sediments are terrific archives that integrate and preserve this evidence, which then allows us to investigate the extent to which a lake has changed given its …


Bayesian Experimental Design For Control And Surveillance In Epidemiology, Bren Case Jan 2023

Bayesian Experimental Design For Control And Surveillance In Epidemiology, Bren Case

Graduate College Dissertations and Theses

Effective public health interventions must balance an array of interconnected challenges, and decisions must be made based on scientific evidence from existing information. Building evidence requires extrapolating from limited data using models. But when data are insufficient, it is important to recognize the limitations of model predictions and diagnose how they can be improved. This dissertation shows how principles from Bayesian experimental design can be applied to surveillance and control efforts to allow researchers to get more out of their data and direct limited resources to best effect. We argue a Bayesian perspective on data gathering, where design decisions are …


Group-Level Frameworks For Data Ethics, Privacy, Safety And Security In Digital Environments, Juniper Lovato Jan 2023

Group-Level Frameworks For Data Ethics, Privacy, Safety And Security In Digital Environments, Juniper Lovato

Graduate College Dissertations and Theses

In today's digital age, the widespread collection, utilization, and sharing of personal data are challenging our conventional beliefs about privacy and information security. This thesis will explore the boundaries of conventional privacy and security frameworks and investigate new methods to handle online privacy by integrating groups. Additionally, we will examine approaches to monitoring the types of information gathered on individuals to tackle transparency concerns in the data broker and data processor sector. We aim to challenge traditional notions of privacy and security to encourage innovative strategies for safeguarding them in our interconnected, dispersed digital environment.

This thesis uses a multi-disciplinary …


On The Construction Of More Lifelike Devices, Shawn Lawrence Beaulieu Jan 2023

On The Construction Of More Lifelike Devices, Shawn Lawrence Beaulieu

Graduate College Dissertations and Theses

Devices which blur the distinction between the living and the inanimate are being reported with heightened frequency. But what forms of organization, and what modes of internal change and worldly interaction, are required for truly lifelike devices, rather than ones which abstractly mimic life in simulation? This thesis presents results from two publications which attempt to mitigate a problem known to limit the performance of artificial neural networks, called ``catastrophic forgetting"; and a third paper which tries to articulate a vision for the construction of more lifelike devices—whose form, function, and putative environment are not conclusively specified prior to their …


Leveraging A Machine Learning Based Predictive Framework To Study Brain-Phenotype Relationships, Sage Hahn Jan 2023

Leveraging A Machine Learning Based Predictive Framework To Study Brain-Phenotype Relationships, Sage Hahn

Graduate College Dissertations and Theses

An immense collective effort has been put towards the development of methods forquantifying brain activity and structure. In parallel, a similar effort has focused on collecting experimental data, resulting in ever-growing data banks of complex human in vivo neuroimaging data. Machine learning, a broad set of powerful and effective tools for identifying multivariate relationships in high-dimensional problem spaces, has proven to be a promising approach toward better understanding the relationships between the brain and different phenotypes of interest. However, applied machine learning within a predictive framework for the study of neuroimaging data introduces several domain-specific problems and considerations, leaving the …