Physical Sciences and Mathematics Commons^™

Precious Plastics - Plastic Brick Machine Fabrication, Timothy Ukaobasi Kanu, Evi Paraskevi Troulis

Architectural Engineering

The goal of this research is to determine the structural parameters of the recycled plastic polypropylene when molded into bricks resembling CMU blocks. To accomplish this, three mechanisms had to be assembled: the shredder, the injector, and the 1x1 mold. A tensile and compression test were to be performed on the plastic brick, and the values would be used to compare the tensile and compressive strength of PP plastic bricks, as well as their modulus of elasticity and stress vs. Strain performance. These values would be analyzed to determine whether it would be feasible to build an entire plastic wall. …

Psf Sampling In Fluorescence Image Deconvolution, Eric A. Inman

Master's Theses

All microscope imaging is largely affected by inherent resolution limitations because of out-of-focus light and diffraction effects. The traditional approach to restoring the image resolution is to use a deconvolution algorithm to “invert” the effect of convolving the volume with the point spread function. However, these algorithms fall short in several areas such as noise amplification and stopping criterion. In this paper, we try to reconstruct an explicit volumetric representation of the fluorescence density in the sample and fit a neural network to the target z-stack to properly minimize a reconstruction cost function for an optimal result. Additionally, we do …

Northeast Pacific Eelgrass Dynamics: Interannual Expansion Distances And Meadow Area Variation Over Time, Stuart H. Munsch, Fiona L. Beaty, Kathryn M. Beheshti, W. Bryant Chesney, Charlie A. Endris, Travis G. Gerwing, Margot Hessing-Lewis, Peter M. Kiffney, Jennifer K. O’Leary, Luba Reshitnyk, Beth L. Sanderson, Ryan K. Walter

Physics

Ecosystems constantly change, yet managers often lack information to move beyond static habitat assumptions. As human impacts and geographic information systems advance, it is important and feasible to quantify past habitat boundary shifts to inform management decisions (e.g. protective perimeters) robust to near-term habitat changes. This is the case in eelgrass (Zostera spp.), an ecosystem engineer that forms dynamic, often protected meadows. Practitioners protect areas to avoid human stress to eelgrass, but they can lack quantitative descriptions of the near-term potential for eelgrass meadows to shift into unprotected areas. Here, we quantified interannual eelgrass meadow boundary shifts within 23 sites …

Spatial Distribution Of Seawater Carbonate Chemistry And Hydrodynamic Controls In A Low-Inflow Estuary, Sarah E. Bartoloni, Ryan K. Walter, Sydney N. Wewerka, Jolie Higgins, Jennifer K. O'Leary, Emily E. Bockmon

Physics

Coastal and estuarine systems play an important role in the global carbon cycle and often have complex carbonate chemistry dynamics due to a multitude of biogeochemical and physical drivers. Compared to classic estuaries, mechanisms driving the distribution of carbonate parameters in low-inflow estuaries are understudied. The spatial distribution of carbonate chemistry and hydrodynamic parameters were characterized in Morro Bay, a short and seasonally hypersaline estuary on the Central California Coast, during the dry, low-inflow season to better understand in situ modifications. Sampling transects were completed in the main channel in June, August, and September of 2018, bracketing both a high …

The Close Agn Reference Survey (Cars): A Parsec-Scale Multi-Phase Outflow In The Super-Eddington Nls1 Mrk 1044, N. Winkel, B. Husemann, M. Singha, V. N. Bennert, F. Combes, T. A. Davis, M. Gaspari, K. Jahnke, R. Mcelroy, C. P. O'Dea, M. A. Pérez-Torres

Physics

Context. The interaction between active galactic nuclei (AGNs) and their host galaxies is scarcely resolved. Narrow-line Seyfert 1 (NLS1) galaxies are believed to represent AGN at early stages of their evolution and to allow one to observe feeding and feedback processes at high black hole accretion rates.

Aims. We aim to constrain the properties of the ionised gas outflow in Mrk 1044, a nearby super-Eddington accreting NLS1. Based on the outflow energetics and the associated timescales, we estimate the outflow’s future impact on the ongoing host galaxy star formation on different spatial scales.

Methods. We applied a spectroastrometric analysis to …

Genealogical Relationship Extraction From Unstructured Text Using Fine-Tuned Transformer Models, Lubomir Stanchev, Carloangello Parrolivelli

Computer Science and Software Engineering

The paper tackles the task of extracting genealogical relationships, such as “sibling-of”, “parent-of”, “child-of”, and “spouse-of”, from unstructured, free-form text. In order to solve the problem, we propose a three-stage pipeline consisting of Named Entity Recognition (NER), Coreference Resolution (CR), and Relationship Classification (RC). NER identifies tokens in the text that refer to people, such as proper nouns or nicknames, using the SpaCy software. CR maps multiple tokens representing pronouns to their antecedents. For example, CR could map “She”, “His sister”, and “Maria” to the antecedent “Maria Johnson”. CR allows us to transform a genealogical relationship between two tokens, such …

A Cradle-To-Gate Life Cycle Assessment Of American Hops In The Craft Beer Supply Chain, Carson Bristol

Master of Science in Environmental Sciences and Management Projects

The hop industry represents a culturally and economically significant industry in the United States due to the product’s significant role in the beer industry, but little is known about the environmental impacts associated with hop production. There exists a significant lack of specific research quantifying the emissions contribution of hop production, and the work that has been done lacks consensus in the scientific community. In an effort to overcome this, this study conducts a cradle-to-gate life cycle assessment (LCA) of aroma hop production broken into four phases, beginning with propagation of seedlings by tissue culture and ending with packaged T-90 …

Assessing The Effectiveness Of Climate Change Science Communication In An Online Carbon Footprint Assessment, Jack Dimmock

Master of Science in Environmental Sciences and Management Projects

Climate change literacy and knowledge are influential in enabling people to take climate change mitigation and adaptation actions. Education about climate change usually takes place through two avenues, formal education and informal institutions, such as museums, television shows, and websites. To help residents reduce their household greenhouse gas emissions and adapt to the local impacts of climate change, the San Luis Obispo Climate Coalition is using the carbon footprint website Bright Action (https://resilientslo.org). Bright Action calculates household carbon footprints, suggests ways to reduce carbon footprints, and provides educational material about climate change mitigation and adaptation. This study seeks to assess …

Building Structures From Mycelium, Noah M. Brown

Physics

The purpose of this project was to develop a method for creating bricks from mycelium and agricultural waste. The bulk of the research happened in two parts, the first part being a period in which different substrates, strains, and methods were used build the bricks. This research took place in San Luis Obispo and was aided by a group of students in PSC392 under Dr. Pete Schwartz in early 2022. After developing a method for constructing these bricks, the research was moved to St. Thomas, Jamaica, in collaboration with an ecovillage called The Source Farm from July to September. The …

Wildfire Spread Prediction Using Attention Mechanisms In U-Net, Kamen Haresh Shah, Kamen Haresh Shah

Master's Theses

An investigation into using attention mechanisms for better feature extraction in wildfire spread prediction models. This research examines the U-net architecture to achieve image segmentation, a process that partitions images by classifying pixels into one of two classes. The deep learning models explored in this research integrate modern deep learning architectures, and techniques used to optimize them. The models are trained on 12 distinct observational variables derived from the Google Earth Engine catalog. Evaluation is conducted with accuracy, Dice coefficient score, ROC-AUC, and F1-score. This research concludes that when augmenting U-net with attention mechanisms, the attention component improves feature suppression …

Wordmuse, John M. Nelson

Computer Science and Software Engineering

Wordmuse is an application that allows users to enter a song and a list of keywords to create a new song. Built on Spotify's API, this project showcases the fusion of music composition and artificial intelligence. This paper also discusses the motivation, design, and creation of Wordmuse.

Predicting Startup Success Using Publicly Available Data, Emily Gavrilenko

Master's Theses

Predicting the success of an early-stage startup has always been a major effort for investors and venture funds. Statistically, there are about 305 million total startups created in a year, but less than 10% of them succeed to become profitable businesses. Accurately identifying the signs of startup growth is the work of countless investors, and in recent years, research has turned to machine learning in hopes of improving the accuracy and speed of startup success prediction.

To learn about a startup, investors have to navigate many different internet sources and often rely on personal intuition to determine the startup’s potential …

Irreducible Representations From Group Actions On Trees, Charlie Liou

Master's Theses

We study the representations of the symmetric group $S_n$ found by acting on

labeled graphs and trees with $n$ vertices. Our main results provide

combinatorial interpretations that give the number of times the irreducible

representations associated with the integer partitions $(n)$ and $(1^n)$ appear

in the representations. We describe a new sign

reversing involution with fixed points that provide a combinatorial

interpretation for the number of times the irreducible associated with the

integer partition $(n-1, 1)$ appears in the representations.

Rainwater Catchment System Designed For California Polytechnic State University Building 34, Jonah S. Aere

Construction Management

California Polytechnic State University currently receives its water supply from either Whale Rock Reservoir, for distilled water, or pumped from six ground wells, for agricultural use. Although the university’s Agricultural College requires a certain amount of water to grow crops, these demands are often not met due to the lack of water within these underground wells. A rainwater capture system could be constructed to ease the water supply burden which is already depleting, reduce wasted drainage, and maintain a sustainable agricultural water source without being dependent on other locations. This would benefit the institution by reducing imported water thereby saving …

Water Quality Assessment For San Luis Obispo Creek And Stenner Creek, Jesse Stewart

Master of Science in Environmental Sciences and Management Projects

Water quality was assessed in five stream segments in San Luis Obispo Creek and its tributary Stenner Creek in spring 2022. Two sites were selected along the San Luis Obispo Creek, and three sites along Stenner Creek. The stream segments were evaluated using the Surface Water Ambient Monitoring Program’s procedures for bioassessment of California streams. This procedure describes the collection of physical, chemical, and biological parameters including streamflow, substrate, flow habitat, and benthic macroinvertebrates toward a quantification of a California Stream Condition Index (CSCI). The California Polytechnic State University: San Luis Obispo, Stream Measurements and Water Quality course provided student …

Thermal Degradation Of Erythritol, Sudheendra Gamoji

Physics

The Insulated Solar Electric Cooker (ISEC) is a double walled Aluminum pot with a resistive heater directly connected to a solar panel whose goal is to create and disseminate cheap solar cookers in rural areas that primarily rely on biomass for cooking. Phase Change Materials (PCMs) like Erythritol, a sugar substitute, take a tremendous amount of energy to melt, and when they solidify they release the energy. Through the use of PCMs, the ISECs will produce enough heat to cook food even after the sun sets. However, PCMs like Erythritol degrade over repeated heat exposure, so the purpose of this …

Seasonal Controls On Nearshore Dissolved Oxygen Variability And Hypoxia In A Coastal Embayment, Ryan K. Walter, Stephen A. Huie, Jon Christian P. Abraham, Alexis Pasulka, Kristen A. Davis, Thomas P. Connolly, Piero L.F. Mazzini, Ian Robbins

Physics

Declining dissolved oxygen (DO) is emerging as an increasingly important stressor in nearshore ecosystems, and there is a growing need to better understand DO dynamics and hypoxia risk in this highly variable environment. In this study, we collected data from monthly cruises on the inner shelf, continuous nearshore moorings inside and outside a small coastal upwelling embayment (San Luis Obispo Bay in Central California), and weekly phytoplankton measurements inside the bay during the upwelling season. Nearshore DO was generally dominated by low-frequency synoptic variability, with increased DO variance near the surface relative to the bottom and inside the bay compared …

Vermicompost Versus Traditional Compost Amendments Leads To Different Soil Health Outcomes In A Mediterranean Vineyard, Elizabeth L. Luck

Master of Science in Environmental Sciences and Management Projects

Compost application has become a common practice in vineyard management to increase soil and crop health, however, the environmental externalities such as greenhouse gas emissions (GHG) from cropping systems that utilize organic fertilizers, such as compost, is uncertain. Vermicompost, which is compost created through the digestion of organic matter by earthworms, and its related ‘extract’ are commonly thought to provide more benefits for soil and crop health compared to standard compost. However, organic fertilizers such as vermicompost, vermicompost extract, and compost have not been compared in their effects on soil health in Mediterranean vineyards. In this two-year study, I assessed …

Environmental Justice Mapping In The U.S. Pacific Island Territory Of Guam, Ben Rocha

Master of Science in Environmental Sciences and Management Projects

Academics, regulators, and the public currently use geospatial analysis tools to identify locations that may be candidates for further environmental justice review in the continental United States (U.S.). However, current environmental justice geospatial analysis tools overlook a small but significant portion of the U.S. - the U.S. Pacific Islands. This study analyzes environmental justice within the U.S. Territory of Guam using existing geospatial analysis methods and publicly available environmental, climate, and socio-economic data to: (1) Spatially map relevant demographic and environmental data and (2) determine the correlation, if any, between the exposure to environmental hazards and the socio-economic status of …

Environmental Justice Mapping In The U.S. Pacific Island Territory Of Guam, Sina Schwenk-Mueller

Master of Science in Environmental Sciences and Management Projects

Academics, regulators, and the public currently use geospatial analysis tools to identify locations that may be candidates for further environmental justice review in the continental United States (U.S.). However, current environmental justice geospatial analysis tools overlook a small but significant portion of the U.S. - the U.S. Pacific Islands. This study analyzes environmental justice within the U.S. Territory of Guam using existing geospatial analysis methods and publicly available environmental, climate, and socio-economic data. This research aims to: (1) spatially map relevant demographic, environmental, and climate data and (2) determine the correlation, if any, between the exposure to environmental hazards, climate …

Barriers And Motivations To Residential Pro-Environmental Actions In San Luis Obispo, Dalis Rae De La Mora

Master of Science in Environmental Sciences and Management Projects

Carbon neutrality has become an important focus for many municipalities, with the inclusion of mitigation measures targeted at the residential sector becoming increasingly prominent for the implementation of climate action plans (CAPs). However, many analyses fall short in identifying the barriers and motivations faced by residents to adopting pro-environmental actions in their daily lives, focusing instead on the available actions themselves. This research aims to identify both the barriers and motivations to adopting pro-environmental behaviors and assess their relationship(s) to key demographic variables, along with climate change perceptions. Using the city of San Luis Obispo (SLO) as a case study, …

Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd

Physics

Positive Thermal Coefficients, PTCs, are materials that abruptly change in resistance in response to changes in temperature. The purpose of this experiment is to explore the viability of using the switching type ceramic PTC thermistor as a replacement for current resistive heaters. These types of PTCs have a nonlinear change in resistance with increases in temperature. This device will be used as a temperature-controlling heating element intended to power an Insulated Solar Electric Cooker (ISEC). The ISEC is designed to cook meals throughout the day for impacted communities as an alternative cooking method that doesn’t require biofuel as an energy …

An Inexpensive Maximum Power Point Tracking System For An Insulated Solar Electric Cooker Using An Off-The-Shelf Buck Converter, Andrew A. Perez

Physics

A specialized control circuit using an off-the-shelf buck converter is built for an Insulated Solar Electric Cooker (ISEC). Cost and efficient power delivery are the focus. An ISEC is synonymous to a direct load heat resistor, allowing a specific maximum power point tracking (MPPT) algorithm and fewer components. Only a microcontroller, voltage sensor, and digital-to-analog converter are used with the buck converter to maximize the power delivered by a 100W solar panel for the 3.3Ω load.

Impacts Of Fertility On Physiological Stress, Photosynthetic Activity, And Crop Development In Salanova Lettuce, Sarah I. Miller

Master of Science in Environmental Sciences and Management Projects

The agricultural industry is one of the main drivers of soil degradation due to conventional crop production methods and overuse of soil which results in accelerated erosion, loss of soil fertility, acidification, and salinization (Lal, 2015). Loss of soil fertility from degradation can be detrimental to crop production as plants grown under nutrient limited conditions show signs of physiological stress and reduced photosynthetic rates leading to reduced yields (Zangani et al., 2021). Organic crop production and fertilizers are viable alternatives to conventional methods as they improve soil fertility and the physiological and biological properties of soil (Ilahi et al., 2021). …

Hydrologic Response Of Little Creek To The 2020 Czu Lightning Complex Fire At The Swanton Pacific Ranch, Kylie E. Dupuis

Master's Theses

In this study, stage, streamflow, and precipitation data was collected from small watersheds in the Swanton Pacific Ranch for the first two hydrologic years following the 2020 CZU Lightning Complex. The Little Creek watershed was setup for high-resolution data collection with four separate stage gauge sites (Main Stem, North Fork, South Fork, and Upper North Fork) and four rain gauge sites (Al Smith House, Ridgeline, Upper North Fork, and Landing 23). Stage gauge sites were also established at Queseria, Archibald, and Mill creeks. Preliminary post-fire rating curves were developed for the four sites of Little Creek. The Main Stem (MS) …

Spatial And Temporal Characteristics Of California Commercial Fisheries From 2005 To 2019 And Potential Overlap With Offshore Wind Energy Development, Yi-Hui Wang, Ryan K. Walter, Crow White, Benjamin I. Ruttenberg

Physics

As climate change accelerates and fisheries management continues to evolve, California's commercial fisheries are changing. To improve the understanding of recent California fisheries dynamics, we compiled and analyzed commercial landings receipts to characterize temporal and spatial variation in landing and value of key fisheries groups within the exclusive economic zone across the state from 2005 to 2019. We found that California fisheries continue a shift first observed in the 1980s from higher‐biomass, lower‐value species, such as coastal pelagic species and market squid, toward lower‐biomass, higher‐value species, such as Dungeness crab Cancer magister and groundfish. Over the 15‐year time series analyzed, …

Deep Learning For Detecting Trees In The Urban Environment From Lidar, Julian R. Rice

Master's Theses

Cataloguing and classifying trees in the urban environment is a crucial step in urban and environmental planning. However, manual collection and maintenance of this data is expensive and time-consuming. Algorithmic approaches that rely on remote sensing data have been developed for tree detection in forests, though they generally struggle in the more varied urban environment. This work proposes a novel method for the detection of trees in the urban environment that applies deep learning to remote sensing data. Specifically, we train a PointNet-based neural network to predict tree locations directly from LIDAR data augmented with multi-spectral imaging. We compare this …

The Close Agn Reference Survey (Cars): Tracing The Circumnuclear Star Formation In The Super-Eddington Nls1 Mrk 1044, N. Winkel, T. A. Davis, I. Smirnova-Pinchukova, V. N. Bennert, F. Combes, M. Gaspari, K. Jahnke, J. Neumann, C. P. O'Dea, M. Pérez-Torres, M. Singha, G. R. Tremblay, H. W. Rix

Physics

Context. The host galaxy conditions for rapid supermassive black hole growth are poorly understood. Narrow-line Seyfert 1 (NLS1) galaxies often exhibit high accretion rates and are hypothesized to be prototypes of active galactic nuclei (AGN) at an early stage of their evolution.

Aims. We present adaptive optics (AO) assisted VLT MUSE NFM observations of Mrk 1044, the nearest super-Eddington accreting NLS1. Together with archival MUSE WFM data, we aim to understand the host galaxy processes that drive Mrk 1044’s black hole accretion.

Methods. We extracted the faint stellar continuum emission from the AGN-deblended host and performed spatially resolved emission line …

Multiple Object Tracking For Marine Science, Nicholas A. Wachter

Computer Science and Software Engineering

As drone and computer vision technology has been improving, many fields of study have been quick to utilize it to improve the accuracy and ease of data collection. The combination of the two technologies is perfect for surveying large areas and identifying features of interest. Marine science utilizes these technologies for activities such as animal tracking and population counting. I am working with the Drones for Marine Science research group at Cal Poly who want to build a fleet of drones that will fly out over the ocean to identify and track various marine animals. My role will be to …

Solid Thermal Storage As An Energy Storage Device In Insulated Solar Electric Cookers: Thermal Modeling And Experiment, Michael Antonio Fernandez

Physics

The use of solid thermal storage (STS) as an energy storage device in insulated solar electric cookers (ISEC) was explored using a thermal simulation before retrofitting an existing cooker without energy storage and testing it under several conditions. STS sizing, material selection, and geometry were examined from both theoretical and practical perspectives and re-examined following experimental results. Characterization of the system’s thermal interfaces and methods to improve their thermal conductivities were investigated resulting in several performance enhancements to the system.