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Full-Text Articles in Physical Sciences and Mathematics

Assessing The Utility Of Breast Cancer Polygenic Risk Scores And Association With Clinical Factors In A Population Of Breast Cancer Patients, John L. Slunecka Jan 2024

Assessing The Utility Of Breast Cancer Polygenic Risk Scores And Association With Clinical Factors In A Population Of Breast Cancer Patients, John L. Slunecka

Dissertations and Theses

INTRODUCTION: Breast cancer (BC) is the most common cancer among women and is classified as a complex disease. Advances in population genomics have led to the development of polygenic risk scores (PRSs) with the potential to enhance current risk models, but replication is often limited. OBJECTIVE: We sought to assess the predictive capabilities of two high-powered BC PRSs in a sample population selected for breast cancer. In addition, the capacity of the PRSs to predict clinical variables that could improve BC screening and treatments was explored. METHODS: Two published PRS algorithms (313 vs 3820) were used to score female subjects …


A Memory Efficient Deep Recurrent Q-Learning Approach For Autonomous Wildfire Surveillance, Jeremy A. Cantor Jan 2024

A Memory Efficient Deep Recurrent Q-Learning Approach For Autonomous Wildfire Surveillance, Jeremy A. Cantor

UNF Graduate Theses and Dissertations

Previous literature demonstrates that autonomous UAVs (unmanned aerial vehicles) have the po- tential to be utilized for wildfire surveillance. This advanced technology empowers firefighters by providing them with critical information, thereby facilitating more informed decision-making processes. This thesis applies deep Q-learning techniques to the problem of control policy design under the objective that the UAVs collectively identify the maximum number of locations that are under fire, assuming the UAVs can share their observations. The prohibitively large state space underlying the control policy motivates a neural network approximation, but prior work used only convolutional layers to extract spatial fire information from …


Transformer-Enabled Deep Reinforcement Learning For Coverage Path Planning, Daniel B. Tiu Jan 2024

Transformer-Enabled Deep Reinforcement Learning For Coverage Path Planning, Daniel B. Tiu

UNF Graduate Theses and Dissertations

Coverage path planning (CPP) is the problem of covering all points in an environment and is a well-researched topic in robotics due to its sheer practical relevance. This paper investigates such an offline CPP problem where the primary objective is to minimize the path length to achieve complete coverage. Furthermore, the literature suggests that taking turns leads to a higher energy use than going straight. To this end, we design a novel objective function that aims to minimize the number of turns as well. We have proposed a deep reinforcement learning (DRL)-based framework that uses a Transformer model. Unlike state-of-the-art …


Properties Of Skew-Polynomial Rings And Skew-Cyclic Codes, Kathryn Hechtel Jan 2024

Properties Of Skew-Polynomial Rings And Skew-Cyclic Codes, Kathryn Hechtel

Theses and Dissertations--Mathematics

A skew-polynomial ring is a polynomial ring over a field, with one indeterminate x, where one must apply an automorphism to commute coefficients with x. It was first introduced by Ore in 1933 and since the 1980s has been used to study skew-cyclic codes. In this thesis, we present some properties of skew-polynomial rings and some new constructions of skew-cyclic codes. The dimension of a skew-cyclic code depends on the degree of its generating skew polynomial. However, due to the skew-multiplication rule, the degree of a skew polynomial can be smaller than its number of roots and hence tricky to …


External Support Structures In Fused Deposition Modeling 3d Printing, Adam Mystkowski Jan 2024

External Support Structures In Fused Deposition Modeling 3d Printing, Adam Mystkowski

Undergraduate Honors Theses

3D Printing, sometimes also referred to as Additive Manufacturing, is a technology that has garnered a lot of attention in the past several years. While the technology has attracted a significant community of hobbyists, the benefits of the technology have also been recognized in manufacturing. While there are many different types of 3D Printing techniques, the most common type is Fused Deposition Modeling (FDM), mainly due to its relatively low cost compared to other types. However, the technique also present a significant limitation: it tends to struggle with models that have overhanging parts. When a layer is extruded by an …


Incorporating Equity Into Sea-Level Rise Planning: Perspectives From Practitioners Across California, Nayré Herrera Jan 2024

Incorporating Equity Into Sea-Level Rise Planning: Perspectives From Practitioners Across California, Nayré Herrera

Cal Poly Humboldt theses and projects

Scholars along with national and state governments have increasingly made calls to incorporate an equity lens into climate adaptation processes and into sea-level rise planning specifically. However, the language used in these high-level policies remains vague. There remains a need to learn from practitioners on the ground about the challenges and opportunities for effectively incorporating an equity lens into sea-level rise adaptation and planning efforts. I conducted interviews with 17 individuals who are working within their agencies or organizations to advance equity across the California coast along with a review of 17 California coastal policy documents to gain insights into …


The Science Of Gravitational-Wave Sources And Beyond Compact Binary Coalescences, Yanyan Zheng Jan 2024

The Science Of Gravitational-Wave Sources And Beyond Compact Binary Coalescences, Yanyan Zheng

Doctoral Dissertations

"This work focuses on the field of gravitational-wave astronomy by extending the scope of detectable sources beyond compact binary coalescences, All the gravitational-wave detections so far come from compact binary coalescences. Focusing on core-collapse supernovae as promising sources for short gravitational-wave transients, this work reports optically targeted searches for gravitational-wave emitted by core-collapse supernovae during the third observing run of the LIGO and Virgo detectors. It also predicts the search sensitivity for the ongoing fourth and forthcoming fifth observing runs. Moreover, the work introduces a novel computational framework for testing the spatial distribution of binary black hole sources, allowing for …


Experimental Investigation Of High-Temperature Brine-Shale Interactions, Anna Atasha Hoffmann Jan 2024

Experimental Investigation Of High-Temperature Brine-Shale Interactions, Anna Atasha Hoffmann

Doctoral Dissertations

"Hydrofracturing (fracking), a common practice in the Petroleum Industry to induce or improve fluid flow in tight formations, creates chemical disequilibrium that further alters the porosity and permeability of host rocks and results in the production of saline and contaminated produced waters (PW). The PW of the Tuscaloosa Marine Shale (TMS) are Na-Ca-Mg-K-Cl brines with mean concentrations of approximately 16% Total Dissolved Solids (TDS) and circumneutral pH. Analysis of composition suggests the PW result from a 20 to 80% dilution of formation waters (relict brines of the Louann Salt) by fracking fluid. Trace element concentrations generally show moderate to strong …


Nitrate Contamination In Two California Groundwater Basins: What Creates Disparities?, Catherine Protiva Jan 2024

Nitrate Contamination In Two California Groundwater Basins: What Creates Disparities?, Catherine Protiva

Scripps Senior Theses

Nitrate contamination is a major problem within California groundwater basins. A form of nitrogen, nitrates leach into groundwater aquifers from the surface where they remain for many decades. The most common source for the contaminant is agricultural sources like nitrogen fertilizer. Consequently, the problem is concentrated in regions of the state with a history of large-scale agricultural production. When water is pulled from contaminated basins and used as drinking water, the nitrates can cause serious negative health consequences, most commonly methemoglobinemia, also known as blue baby syndrome. In this thesis, I will examine what factors contribute to a region’s ability …


Improving Accessibility And Understanding: Studying The Impact Of Human Activities And Dam Removals On Anadromous Fish Species In The Pacific Northwest, Adia F. Bennett Jan 2024

Improving Accessibility And Understanding: Studying The Impact Of Human Activities And Dam Removals On Anadromous Fish Species In The Pacific Northwest, Adia F. Bennett

Scripps Senior Theses

Human activities in North American watersheds have significantly impacted anadromous fish, causing some species of salmon and steelhead to become threatened and endangered. These fish hold ecological, cultural, and economic importance, yet factors such as habitat destruction, overfishing, pollution, climate change, and hydroelectric dams continue to degrade populations. Dams are particularly harmful to anadromous fish, sparking a recent movement advocating for dam removals. This study uses NOAA’s 2022 Biological Viability Assessment to examine the response of anadromous fish to recent dam removals in the Pacific Northwest. Four populations were selected to analyze due to their interaction with sites that had …


Transition Towards A Brighter Future: Energy Usage Analysis At Pilgrim Place And Recommendations For Decarbonization, Zhuoyao Wu Jan 2024

Transition Towards A Brighter Future: Energy Usage Analysis At Pilgrim Place And Recommendations For Decarbonization, Zhuoyao Wu

Scripps Senior Theses

This thesis summarizes the semester-long project I and other Environmental Analysis major students collaborated on for the EA 190 Capstone Project aims to find effective methods to reduce emissions and increase energy efficiency. Our group partnered with the Climate Resilience Initiative team (CRI) at Pilgrim Place, a social and environmental justice-focused retirement community in Claremont, CA. As the demand for effective methods for energy efficiency in communal spaces increases, we have conducted an energy analysis and researched potential functional technologies to replace high fossil fuel consumption sources. Our final deliverable is a written report that analyzes the data we collected …


Machine Learning And Natural Language Processing For Crossword Puzzles, Finn Brennan Jan 2024

Machine Learning And Natural Language Processing For Crossword Puzzles, Finn Brennan

Senior Projects Spring 2024

Senior Project submitted to The Division of Science, Mathematics and Computing of Bard College.


Locigraph: Ai Agent Framework For Browser-Based Knowledge Graph Construction, Nathan Cho Jan 2024

Locigraph: Ai Agent Framework For Browser-Based Knowledge Graph Construction, Nathan Cho

Senior Projects Spring 2024

This work presents LociGraph, an artificial intelligence agent that can autonomously search information on the non-public web, such as email inboxes, online communities, social media, or web applications not searchable on a public search engine. With a given query, the agent will browse the web using the keyboard and mouse to find a webpage containing the relevant information and extract the information in a structured format. For example, if the agent is given the query [Alex, studied at, ?] on your email inbox, the agent will start by typing “Alex” into the search bar, click on email related to …


Dumonym: Crafting And Assessing Lexical Simplification, From Algorithms To Models, Jeremias Brea De Los Angeles Jan 2024

Dumonym: Crafting And Assessing Lexical Simplification, From Algorithms To Models, Jeremias Brea De Los Angeles

Senior Projects Spring 2024

Lexical Simplification is the process of replacing complex words with simpler alternatives in a given text. This project aims to use different approaches in the field of Natural Language Processing to create a series of lexical Simplification models. The framework of lexical simplifiers will also be explored and researched, to give more insight of the mechanisms and approaches used to achieve successful text simplification. I will develop a pipeline of steps, based on my research, with the aim to create a framework for a functional lexical simplification model. I will develop a series of distinct lexical simplification models based on …


Folding And Embedding Cubical Complexes, Skye Rothstein Jan 2024

Folding And Embedding Cubical Complexes, Skye Rothstein

Senior Projects Spring 2024

Senior Project submitted to The Division of Science, Mathematics and Computing of Bard College.

In this project we study the folding properties of several special classes of cubical complexes. First, we look at polyominoids, which are arrangements of congruent squares in 3-space, glued edge-to-edge at 90° and 180° angles. We construct and analyze the mechanical configuration space for n-cell polyominoids, which is a graph with vertex set given by all n-cell polyominoids, where two vertices are connected by an edge if you can transform one into the other by one hinge movement. For n = 4, we provide a complete …


Pumping A Transition, Christopher Daniel Hallman Jan 2024

Pumping A Transition, Christopher Daniel Hallman

Senior Projects Spring 2024

This thesis is an exploration into the physical mechanism responsible for the acceleration experienced when pumping a ramp on a bicycle, skateboard, or related human-powered vehicle. Pumping is the technique by which one propels oneself on a ramp, which is very similar to the process of pumping a playground swing. It is my hypothesis that the acceleration one experiences when pumping a ramp is primarily due to the conservation of angular momentum, affected by altering ones moment of inertia relative to the focal point of the curve through which one is traveling. This report documents my attempt to accurately describe …


Sedimentary, Claire E. Sullivan Jan 2024

Sedimentary, Claire E. Sullivan

Senior Projects Spring 2024

S E D I M E N T A R Y is a mixed-media exploration of the layers and connections between the synthetic and natural world -- Where do the natural and built environments begin and end? In what ways might natural elements and man-made materials mimic or defy one another? What aesthetic, economic, or sustainable possibilities can be unearthed when nature's laws and patterns are applied to our calculated, built environment? Most importantly, how responsible must we hold ourselves and one other for our particular interactions with and impact on our environment? S E D I M E N …


Consistent Monte Carlo Methods For Non-Linear Applications In Light Transport, Zackary T. Misso Jan 2024

Consistent Monte Carlo Methods For Non-Linear Applications In Light Transport, Zackary T. Misso

Dartmouth College Ph.D Dissertations

The study of light transport focuses on describing the propagation of light from emitters to sensors through accurately describing the interactions light can undergo with everything in between. Physically-based rendering is the process of applying the laws of light transport to formulate practical algorithms which simulate the flow of light for the purpose of synthesizing images of virtual environments.

Unfortunately, there are very few interesting scene configurations which can be computed analytically. Instead, modern solutions predominantly rely on Monte Carlo integration to stochastically estimate the transfer of light since the process is both unbiased and consistent. Meaning, it is expected …


Random Walk Methods For Geometry Representation Agnostic Transport, Dario R. Seyb Jan 2024

Random Walk Methods For Geometry Representation Agnostic Transport, Dario R. Seyb

Dartmouth College Ph.D Dissertations

In computer graphics, we use geometry representations to model a wide range of virtual scenes—from the fantastical worlds shown in animated movies to intricate mechanical parts.
These representations provide the context for transport problems—light transport is used to produce images of virtual scenes and diffusive transport to simulate distributions of quantities like heat.

There are many types of representations each with their own advantages.
For example, explicit ones make it easy to directly manipulate surfaces, while implicit representations allow for intuitive modeling by non-technical users and straightforward integration into machine learning systems.
Unfortunately, many algorithms that work on these digital …


Towards Explainable Neural Network Fairness, Mengdi Zhang Jan 2024

Towards Explainable Neural Network Fairness, Mengdi Zhang

Dissertations and Theses Collection (Open Access)

Neural networks are widely applied in solving many real-world problems. At the same time, they are shown to be vulnerable to attacks, difficult to debug, non-transparent and subject to fairness issues. Discrimination has been observed in various machine learning models, including Large Language Models (LLMs), which calls for systematic fairness evaluation (i.e., testing, verification or even certification) before their deployment in ethic-relevant domains. If a model is found to be discriminating, we must apply systematic measure to improve its fairness. In the literature, multiple categories of fairness improving methods have been discussed, including pre-processing, in-processing and post-processing.
In this dissertation, …


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, …


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 …


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 …


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 …


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 …


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 …


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 …


Stable Oxygen Isotope Variability As A Proxy For Large-Scale Dynamics Of The South American Summer Monsoon, Rebecca Orrison Jan 2024

Stable Oxygen Isotope Variability As A Proxy For Large-Scale Dynamics Of The South American Summer Monsoon, Rebecca Orrison

Electronic Theses & Dissertations (2024 - present)

Terrestrial archives of oxygen isotope records are particularly important for the study of South American hydrology, where hydroclimate observations over the historical period are sparse and often not long enough to characterize multidecadal to centennial-scale changes. Knowledge of such low-frequency changes is critically important for interpreting and constraining projections of future change and detecting the emergence of forced change beyond the envelope of natural variability. This dissertation focuses on the past, present, and future of South American tropical and subtropical climate, with an emphasis on the mature phase of the monsoon season (December, January, and February; DJF) using oxygen isotopes …