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Articles 1861 - 1890 of 291657

Full-Text Articles in Physical Sciences and Mathematics

Corrosion Protection Assessment Of Offshore Wind Turbine Substructures Using Beasy Cp Simulation Analysis, Chuan-Yang Wan, Hung-Hua Sheu, Sheng-Yu Wang, Yao-Ming Wang, Wei-De Chen, Ming-Yuan Lin, Hung-Bin Lee Jun 2026

Corrosion Protection Assessment Of Offshore Wind Turbine Substructures Using Beasy Cp Simulation Analysis, Chuan-Yang Wan, Hung-Hua Sheu, Sheng-Yu Wang, Yao-Ming Wang, Wei-De Chen, Ming-Yuan Lin, Hung-Bin Lee

Journal of Marine Science and Technology–Taiwan

This study investigates the corrosion protection assessment of offshore wind turbine substructures established in the waters off Keelung, Taiwan. First, a cathodic protection system for the monopile foundation is designed and established. The Boundary Element Method (BEM) is applied using the BEASY simulation software to develop a 3D geometric model for cathodic protection. In the steel monopile simulation analysis, the exposed marine environment is set based on the sea conditions of the Keelung small boat marina, including parameters such as salinity, resistance, and polarization curves, to establish an effective cathodic protection system for underwater structures. By simulating these parameters, a …


Face-To-Face Versus Distance Education In Competence-Based Maritime Education And Training, Clara Borén, Marcella Castells-Sanabra, Manel Grifoll Jun 2026

Face-To-Face Versus Distance Education In Competence-Based Maritime Education And Training, Clara Borén, Marcella Castells-Sanabra, Manel Grifoll

Journal of Marine Science and Technology–Taiwan

The COVID-19 pandemic created significant challenges for higher education, with universities being shut down and face-to-face teaching and assessment shifting to an online format. This presented an opportunity to focus on the continuity of learning through distance education, especially in the maritime context, due to the on-board training requirements, and even though five years have passed, this shift has reshaped the education landscape, proving that remote learning has come to stay.

At the Barcelona School of Nautical Studies, we have developed a weather routing software in the framework of distance education and teaching innovation. We conducted a teaching trial alternatively …


A Bibliometric And Visualization Analysis Of Global Giant Clam Research, Chia-Hsiang Chen, Chih-Hsien Chang Jun 2026

A Bibliometric And Visualization Analysis Of Global Giant Clam Research, Chia-Hsiang Chen, Chih-Hsien Chang

Journal of Marine Science and Technology–Taiwan

In this study, bibliometric analysis and visualization tools were used to investigate the academic network and knowledge structure surrounding global giant clam research. A total of 551 relevant publications from the Web of Science database, published from 1900 to 2024, were analyzed. The findings indicate that research on giant clams has experienced considerable growth since 2012, peaking in publication output in 2021. Sixty-six countries were represented in the study sample, with the United States, Australia, China, Singapore, and Japan being the most represented ones. Notably, the rate of international collaboration was only 29%, highlighting a need for additional integrated cross-border …


(Re)Claiming Homeplace: Dance As Embodied Resistance & Healing For Health & Spatial Justice, Preeya G. Kannan Jun 2026

(Re)Claiming Homeplace: Dance As Embodied Resistance & Healing For Health & Spatial Justice, Preeya G. Kannan

University Honors Theses

This thesis argues that dance functions as both an upstream public health intervention and a form of radical spatial resistance; creating healing, agency, and belonging among historically marginalized communities. Drawing on bell hooks' concept of homeplace, Jasbir Puar's assemblage theory, Nancy Krieger's eco-social theory, and Katherine McKittrick's Black geographies, I position the body as both an ecological and political landscape shaped by histories of colonialism, racial capitalism, displacement, and resilience.

Through this community-based participatory research study, Homeplace, I explore dance as a form of social prescription that centers liberation rather than pathology. Movement is often reduced in public health discourse …


Engineering Nanoelectrocatalytic Systems For Co2 And Nitrate Conversion Into Value-Added Chemicals, Abdelrahman Mohamed Abdelmohsen Jun 2026

Engineering Nanoelectrocatalytic Systems For Co2 And Nitrate Conversion Into Value-Added Chemicals, Abdelrahman Mohamed Abdelmohsen

Theses and Dissertations

The thesis addresses two major related environmental crises: nitrate pollution of water systems and the ever-increasing levels of atmospheric carbon dioxide. Both challenges are closely linked to anthropogenic disturbance of nitrogen and carbon cycles and require sustainable, energy efficient mitigation techniques. In this study, we investigate electrochemical conversion routes as a unified approach to convert these pollutants into value-added compounds: ammonia (NH3) via nitrate reduction (NO3-RR) and ethylene (C2H4) via carbon dioxide reduction (CO2RR). The first half of this work deals with the design and engineering of Cu-Zn alloy electrocatalysts for efficient NO3-RR. Tuning the alloy composition and surface nanostructure …


Automatic Glossing In Under-Resourced Languages: Case Studies In Bribri And Cook Islands Māori, Carter D. Anderson Jun 2026

Automatic Glossing In Under-Resourced Languages: Case Studies In Bribri And Cook Islands Māori, Carter D. Anderson

Linguistics Undergraduate Senior Theses

Interlinear glossing is a major task in Indigenous language documentation. In this paper, I explore how effectively two Large Language Models, ByT5 and Gemini 2.5 Flash, can produce interlinear glossed text. I also examine how prompting an LLM with different types of information (dictionary entries, other training samples, and translations) can augment model performance. I apply these models to two under-resourced Indigenous languages: Bribri, which is morphologically complex from Costa Rica, and Cook Islands Māori, which has a simpler morphology and is from the Cook Islands in the Pacific Ocean. ByT5 exhibits much better performance when glossing Cook Islands Māori …


Examining The Impact Of The Palisades And Eaton Fires On Air Quality In Los Angeles, Ryan Edward Glenn Jun 2026

Examining The Impact Of The Palisades And Eaton Fires On Air Quality In Los Angeles, Ryan Edward Glenn

Earth Sciences Undergraduate Senior Theses

Wildland-urban-interface (WUI) fires in the US are increasing in frequency and intensity with disproportionately large impacts on air quality and human health. In January 2025, the Palisades and Eaton wildfires swept across the Los Angeles Basin, burning residential areas and destroying vegetation. Despite their significance, WUI fires remain understudied compared to wildland fires, especially in regard to emissions composition. Here, I utilize a combination of field samples, modeling, and remotely-sensed datasets to survey the emissions profiles and variations during the 2025 Palisades and Eaton wildfires. I find that 75.1% of Los Angeles County was exposed to surface PM2.5 rated ‘unhealthy’ …


Assessing The Origin Of The Talus Deposit In King Ravine In The Presidential Range Of New Hampshire, Margaret M. Keating Jun 2026

Assessing The Origin Of The Talus Deposit In King Ravine In The Presidential Range Of New Hampshire, Margaret M. Keating

Earth Sciences Undergraduate Senior Theses

The timing and mechanisms driving the retreat of the Laurentide Ice Sheet (LIS) after the Last Glacial Maximum (LGM; 26-19 ka) in the Presidential Range of the White Mountains, New Hampshire, remains inconsistently interpreted. King Ravine, located within the Presidential Range, contains a landform that preserves geomorphic evidence relevant to this debate. Here, I investigate the origin of this landform by assessing its age, surficial morphology, and internal structure. I present a topographic analysis of King Ravine, including a detailed new geomorphic map of the drainage basin and deposit. To constrain the timing of landform formation and activity, I determined …


Exploring Paleoproterozoic Marine Redox States In A Young Banded Iron Formation From The Needle Mountains, Jaya Sharma Jun 2026

Exploring Paleoproterozoic Marine Redox States In A Young Banded Iron Formation From The Needle Mountains, Jaya Sharma

Earth Sciences Undergraduate Senior Theses

Banded iron formations (BIF) are redox-dependent chemical sedimentary rocks that have served as proxies for marine and atmospheric oxygen and iron conditions throughout Earth's history. While abundant in the Archean and early Proterozoic, the widespread deposition of BIFs declined following the Great Oxidation Event, as oxygenated surface waters prevented the accumulation of ferrous iron. However, the Needle Mountains, located in southwestern Colorado, house an anomalously young BIF deposited between 1786±10 Ma - 1801±6 Ma given existing geochronology. Here, we use rare earth element (REE) systematics, bulk chemistry, and petrographic analysis to determine the depositional conditions under which this BIF was …


Carbon Dioxide And Methane Greenhouse Gas Fluxes In Coastal Salt Marshes Of Cape Cod, Massachusetts, Hannah C. Clark Jun 2026

Carbon Dioxide And Methane Greenhouse Gas Fluxes In Coastal Salt Marshes Of Cape Cod, Massachusetts, Hannah C. Clark

Earth Sciences Undergraduate Senior Theses

Preserving “Blue Carbon”, or the carbon buried in suboxic or anoxic soil in coastal environments, is emerging as a potential natural climate solution (Fargione et al., 2018; Mcleod et al., 2011). Tidal wetlands act as both carbon sinks through uptake by vegetation and soil storage and serve as carbon sources via lateral transport of carbon through tidal flushing and emission of greenhouse gases (GHGs), including carbon dioxide (CO₂) and methane (CH₄) (Bansal et al., 2023). The C-NEWTS (“Carbon New England Wetland Time Series”) project, an NSF-funded collaboration between the USGS Woods Hole Coastal and Marine Science Center, Woods Hole Oceanographic …


Custom Sbc Gps Tracking And Geocaching Carputer Software Development And Implementation, Joshua A. Davis Jun 2026

Custom Sbc Gps Tracking And Geocaching Carputer Software Development And Implementation, Joshua A. Davis

University Honors Theses

This thesis argues that hardware-integrated capstone projects develop software engineering skills that traditional coursework cannot replicate. A team of eight developers built a GPS tracking system on a Raspberry Pi 4 over two academic terms, integrating real-time position streaming, the APRS amateur radio protocol for network-independent location sharing, and PostGIS spatial queries for "new road" detection. The system implements SmartBeaconing for adaptive GPS data reduction, achieving approximately 80% storage savings while preserving route fidelity. The project exposed challenges absent from classroom assignments: hardware debugging without stack traces, cross-layer integration failures, and coordination overhead when deploying to unfamiliar architecture; demonstrating that …


Beyond The Best Prompt: A Coverage View Of Multilingual Reasoning, Harshiv Mistry Jun 2026

Beyond The Best Prompt: A Coverage View Of Multilingual Reasoning, Harshiv Mistry

University Honors Theses

Multilingual LLMs reason more accurately in English than in other languages, and recent work links part of this gap to reasoning behavior: native-language traces contain fewer cognitive behaviors (verification, backtracking, subgoal setting, backward chaining) that support effective problem solving. We test whether prompting for these behaviors at inference time narrows the gap, across seven conditions varying chain-of-thought, instruction and reasoning language, and cognitive-behavior descriptions, on two models, three languages. We find that English-scaffolded reasoning is the strongest single strategy on both models, closing the Hindi gap on Qwen, though the explicit scaffold's value over plain chain-of-thought is model-dependent. Beyond aggregate …


Effects Of Changing Fire Regimes On Black Huckleberry Habitat Suitability, Emily Labarge Jun 2026

Effects Of Changing Fire Regimes On Black Huckleberry Habitat Suitability, Emily Labarge

University Honors Theses

Black huckleberries are a significant cultural, ecological, and economic species in the Pacific Northwest. Historically, black huckleberries were tended with cultural fire by Indigenous peoples, and now also hold importance as a resource in the non-timber forest product economy. Research has begun on the impacts of climate change on suitable black huckleberry habitat and on changing fire regimes, but not in relation to each other. To address this gap, I examined the area of overlap between suitable black huckleberry habitat and fire burn probability into mid-century climate projections. I determined the current ownership entities with management jurisdiction in areas with …


Chondrites From Northwestern Nevada: The Jungo Dense Collection Area, Nico Morrelli Jun 2026

Chondrites From Northwestern Nevada: The Jungo Dense Collection Area, Nico Morrelli

University Honors Theses

Dense collection areas are regions where meteorites are more frequently found, and can help researchers study the meteorite flux to Earth. The Jungo dry lake bed is a dense collection area (DCA) in Humboldt County, Nevada and is currently the recovery location of eleven officially classified meteorites. Five of these samples were classified as part of this work. All five are ordinary chondrites, two of which are likely paired with previously classified Jungo samples. Jungo 021 is likely paired with Jungo 005, and Jungo 017 is likely part of the previously established pairing group of Jungo 002, 003, and 004. …


Effects Of Fine Sediment On The Productivity Of Stream Ecosystems In The Pacific Northwest, Veena I. Davis Jun 2026

Effects Of Fine Sediment On The Productivity Of Stream Ecosystems In The Pacific Northwest, Veena I. Davis

University Honors Theses

Salmon are important to the culture, ecosystem and economy of the Pacific Northwest. However, populations have declined significantly since European colonization. Salmon require specific conditions for each life stage and are highly sensitive to environmental stressors. Excess fine sediment is a leading form of pollution as it degrades salmon spawning habitat and the benthos upon which their main food source, stream insects, live. To evaluate the effect of sediment pollution on food availability for salmon smolt, we conducted an experiment  estimating the amount of stream insect biomass and calories lost due to sediment pollution. We counted insects on substrate samples …


Mycelial Modeling: Teaching Biology Students Statistical Modeling With Mushrooms, Colette Wolf Jun 2026

Mycelial Modeling: Teaching Biology Students Statistical Modeling With Mushrooms, Colette Wolf

University Honors Theses

This paper summarizes and describes the development of a set of learning materials that were created to educate students and professionals from other fields in statistical modeling techniques. These materials are primarily aimed at biology students, but are still intended to be useful for anyone who is interested in incorporating decision trees and random forest models into their personal research in the future. By directing the reader towards the JMP software, these materials navigate around the statistical knowledge base and coding implementation practices that otherwise would serve as a barrier to learning statistical modeling techniques, and instead focus on the …


Assessing Spatial Distribution Of Plausible Earthquake-Triggered Landslides Relative To Ca. 1000 Ybp Earthquake On The Gales Creek Fault, Jacqueline Rheingans Jun 2026

Assessing Spatial Distribution Of Plausible Earthquake-Triggered Landslides Relative To Ca. 1000 Ybp Earthquake On The Gales Creek Fault, Jacqueline Rheingans

University Honors Theses

Modern coseismic landslides cluster near the surface trace of the fault that ruptured, suggesting that clustering of paleolandslides may record information about paleoearthquakes. This study documents the pattern of prehistoric landslides near the Gales Creek Fault (GCF), northwest Oregon, to assess whether it reflects an independently known paleoearthquake. The GCF is located northwest of Portland through the Cascadia fore-arc basin where landslides are often triggered by intense rainfall during the wet season or potentially by seismic shaking on the megathrust or on crustal faults. In order to understand how a seismic event on the GCF will impact landslide distribution I …


Pitching Fwar Vs Bwar As Predictors Of Team Success In The Mlb Regular Season, Jason Lee Jun 2026

Pitching Fwar Vs Bwar As Predictors Of Team Success In The Mlb Regular Season, Jason Lee

University Honors Theses

Pitching Wins Above Replacement (WAR) is an area of sabermetrics capable of being used to predict regular season success in Major League Baseball. Fangraphs WAR (fWAR) and Baseball Reference WAR (bWAR) were used to construct regression models to predict regular season winning percentage, to build logistic models to establish a relationship between pitching WAR and the probability to win an individual regular season game, and to overlay density plots to consider WAR accumulation by pitching role and observe the difference of impact between starter and relief pitchers. This research finds that while pitching fWAR and pitching bWAR are both statistically …


The Role Of Urban Forests In Mitigating Flooding Effects: A Case Study In Savannah, Georgia, Gillian Bush Jun 2026

The Role Of Urban Forests In Mitigating Flooding Effects: A Case Study In Savannah, Georgia, Gillian Bush

Undergraduate Theses, Capstones, and Recitals

Flooding in coastal communities is shaped by the interaction between natural systems and urban development. Chatham County, a low-elevation region in the Savannah, Georgia metropolitan area along the eastern coast of the United States, is prone to coastal storms and frequently affected by flooding. It serves as a useful case study to better understand the factors behind flooding and the areas that are most at risk. This study uses GIS-based analysis to examine the overlap between flood risk, urban forest cover, and impervious surfaces. The results indicate elevated vulnerability along major transportation corridors and barrier islands, where high-risk flood zones …


Digital Bodily Autonomy: Consent Issues, Labor Displacement, And Legal Understandings Of Ai Generated Deepfake Pornography, Mariah Barrett Jun 2026

Digital Bodily Autonomy: Consent Issues, Labor Displacement, And Legal Understandings Of Ai Generated Deepfake Pornography, Mariah Barrett

Undergraduate Theses, Capstones, and Recitals

In the United States, nonconsensual pornographic deepfakes are becoming an increasingly prevalent problem as AI deepfake creation software improves and becomes widely available. Despite this, patchwork legislation across the country is inconsistent and conflicting regarding this issue. In this paper, I explore the background of pornography and obscenity laws and demonstrate how these frameworks are not properly constructed to apply to the digital sphere. Then, I address major themes within deepfake literature such as consent issues, bodily autonomy, labor displacement, and verifiable identity as a commodity through the case study of OnlyFans. I explore current and proposed legislation within the …


Rapid-Prototyping Nanofabrication: Lcd-Based Projection Lithography And Physical Vapor Deposition, Sabeel Saleem Mohammmed Jun 2026

Rapid-Prototyping Nanofabrication: Lcd-Based Projection Lithography And Physical Vapor Deposition, Sabeel Saleem Mohammmed

University Honors Theses

The semiconductor industry's continued growth, driven in large part by demand for artificial intelligence hardware, has highlighted the need for greater workforce development in regions adjacent to major fabrication centers like Oregon's Silicon Forest. This capstone project lays the groundwork for a small scale and student led semiconductor fabrication lab at Portland State University by demonstrating two of the core steps in chip manufacturing: photolithography and thin film deposition. Rather than relying on conventional fixed reticles, this work explores a unique, low cost approach to patterning that uses an ultraviolet-compatible liquid crystal display (LCD) as a programmable reticle, allowing arbitrary …


A Novel, Embedding-Based Approach To Longitudinal Survey Data Imputation, Julia Rezvani Jun 2026

A Novel, Embedding-Based Approach To Longitudinal Survey Data Imputation, Julia Rezvani

University Honors Theses

Longitudinal surveys are ubiquitous in the social sciences as a means of tracking changes in behavior and opinions with time and identifying potential causal mechanisms. These surveys are frequently plagued by missing data and semantic drift, both of which limit their effectiveness and scientific utility. Imputation algorithms allow researchers to fill gaps in collected survey datasets, imperfectly reconstructing lost data. Although deep learning algorithms have been used in imputation to great success, approaches which simultaneously leverage the semantic and temporal structure of longitudinal surveys have not yet been developed. We propose a novel imputation architecture which is capable of leveraging …


Bias, Structure, And Inference In Applied Network Analysis, Anna Vasenina Jun 2026

Bias, Structure, And Inference In Applied Network Analysis, Anna Vasenina

Dartmouth College Ph.D Dissertations

This dissertation develops mathematical and statistical methods for extracting reliable information from network data across biological applications, with an emphasis on understanding what observed network structure can and cannot resolve. The first study leverages protein–protein interaction network topology in the c-di-GMP signaling system of Pseudomonas fluorescens, showing that node centrality measures accurately classify protein domain types and that physical interaction structure contributes statistically significant predictive power for biofilm formation phenotypes across nearly 200 environments, while gene expression does not. The second study examines sampling bias in lemur-plant trophic interaction networks in Madagascar, demonstrating that differential detection of diurnal versus …


Refining A Flow Injection Analysis Method For Trace Concentrations Of Iron In Seawater, Brooke I. Stafford, Liam W. Hodgson, Noah S. Schuhmann, Elijah J. Vestal, Claire P. Till Jun 2026

Refining A Flow Injection Analysis Method For Trace Concentrations Of Iron In Seawater, Brooke I. Stafford, Liam W. Hodgson, Noah S. Schuhmann, Elijah J. Vestal, Claire P. Till

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Iron is an essential micronutrient required for the growth of phytoplankton, the base of the oceanic food chain. Iron exists in the ocean in extremely low concentrations, limiting primary productivity in ~⅓ of the surface ocean, and can be affected by physical processes such as upwelling of water masses, and by biological and chemical processes within the water. In order to further our understanding of iron availability in the ocean, here we refine and improve our understanding of an analytical method to measure nanomolar iron in seawater. The method used is an adaptation of Lohan et al. (2006), a flow …


Exploring The Relationship Between Tree Dbh And Lichen Cover On Coast Redwood, Grace M. Personeus, Sierra Gittleman, Alisa A. Zarattini Jun 2026

Exploring The Relationship Between Tree Dbh And Lichen Cover On Coast Redwood, Grace M. Personeus, Sierra Gittleman, Alisa A. Zarattini

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

We investigated the relationship between Diameter at Breast Height (DBH) and lichen cover on coast redwood (Sequoia sempervirens) to see if larger trees had higher percentages of cover. We measured cover using 10 cover classes on the southeastern and southwestern sides of trees in a secondary growth forest. We found a significant relationship between DBH and cover, yet no significant difference between the two sides measured. We suggest that further research with a larger sample size and more varied age classes will provide further insight into the relationship.


Allosteric And Uncompetitive Inhibition Of Yeast Alcohol Dehydrogenase Identified By Enzyme Kinetics, Dylan Jeremy Harrison, Jenny A. Cappuccio Jun 2026

Allosteric And Uncompetitive Inhibition Of Yeast Alcohol Dehydrogenase Identified By Enzyme Kinetics, Dylan Jeremy Harrison, Jenny A. Cappuccio

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Enzyme kinetics is a powerful technique used to quantify the rate at which an enzyme converts a substrate into a product and to identify potential inhibitors. In this study, kinetic analysis was employed to assess the activity of yeast alcohol dehydrogenase (YADH) in the presence and absence of sweeteners commonly found in alcoholic beverages. YADH catalyzes the oxidation of ethanol to acetaldehyde using NAD⁺ as a cofactor; the reduction to NADH can be monitored spectrophotometrically at 340 nm. Based on structural similarities to the ribose moiety of NAD⁺, it was hypothesized that sucrose and sucralose could directly interact with the …


A Professional Development Course On Data-Driven Dynamical Systems At A Primarily Undergraduate Institution: Part A - Scientific Content, Alessandro M. Selvitella, Jeffrey R. Anderson Jun 2026

A Professional Development Course On Data-Driven Dynamical Systems At A Primarily Undergraduate Institution: Part A - Scientific Content, Alessandro M. Selvitella, Jeffrey R. Anderson

CODEE Journal

In the age of data-driven decision making, ordinary differential equations (ODEs) remain a powerful and interpretable framework for modeling dynamic processes, especially when integrated with modern tools from statistical learning and data-driven dynamical systems. Yet, general undergraduate and graduate curricula do not typically address key opportunities in data-driven dynamical systems.

This first paper in a series focuses on the mathematical and methodological core of a professional development course first developed in the academic year 2025-2026 at a Primarily Undergraduate Institution, Purdue University Fort Wayne. The curriculum developed in this course emphasized how regression, regularization, and sparse identification can be used …


Phase-Resolved Measurement And Arbitrary Mode Conversion Of Structured Light, Somayeh Ghazanfarpour Jun 2026

Phase-Resolved Measurement And Arbitrary Mode Conversion Of Structured Light, Somayeh Ghazanfarpour

Electronic Theses and Dissertations

This dissertation presents a single-shot phase and amplitude retrieval technique based on spatial light modulator (SLM)-based digital holography. The proposed method enables accurate reconstruction of complex optical fields from a single interferogram, reducing sensitivity to environmental fluctuations and improving experimental stability compared to conventional multi-shot approaches. In addition, a programmable arbitrary mode converter is developed using SLM-based wavefront shaping. By introducing controlled astigmatism and engineering the differential Gouy phase between orthogonal components, the system enables flexible transformation between structured light modes, including Hermite–Gaussian and Laguerre–Gaussian beams. Numerical results demonstrate reliable phase recovery and efficient mode conversion, validating the performance of …


Quantifying Terrain Controls On Satellite-Based Snow Water Equivalent Estimation: A Spatially Explicit Machine Learning Approach, Brant Giovannetti Jun 2026

Quantifying Terrain Controls On Satellite-Based Snow Water Equivalent Estimation: A Spatially Explicit Machine Learning Approach, Brant Giovannetti

Geography and the Environment: Graduate Student Capstones

Terrain variables are widely incorporated into machine learning Snow Water Equivalent (SWE) models but are rarely evaluated for their independent contribution relative to spectral predictors. Using a four-tier stepwise Random Forest framework with Harmonized Landsat Sentinel-2 imagery and Airborne Snow Observatory LiDAR ground truth, this study isolates the contribution of elevation, slope, northness, and eastness across Peak and Ablation snowpack regimes in the East Taylor River Watershed, Colorado. During peak snowpack, adding terrain improved R² by 0.214, with elevation alone accounting for 42.8% of model importance. During ablation, full-dataset terrain gains were modest, increasing R² by only 0.036. However, when …


Geospatial Governance Failures In The Department Of Defense: Contractor Noncompliance, Ai Adoption, And The Parallel Treatment Of Gis And Cybersecurity, Lyndsey Olmstead Jun 2026

Geospatial Governance Failures In The Department Of Defense: Contractor Noncompliance, Ai Adoption, And The Parallel Treatment Of Gis And Cybersecurity, Lyndsey Olmstead

Geography and the Environment: Graduate Student Capstones

The Department of Defense's treatment of geographic information systems and cybersecurity as parallel rather than integrated policy domains produces geographically predictable vulnerability patterns across its global military installation footprint. This capstone investigates that conclusion through original spatial analysis, constructing a five-variable composite geospatial vulnerability index across the six U.S. Combatant Command regions using publicly available unclassified data. EUCOM ranked highest overall, driven by GPS/PNT spoofing density, commercial satellite coverage, and cyber incident frequency; CENTCOM ranked second, driven by OSINT exposure incidents and governance risk. The null hypothesis of random geographic distribution is rejected. Findings confirm the structural governance gap documented …