Digital Commons Network^™

Spectrum Of The Lakes: Using Satellite Remote Sensing To Unveil Water Color In Minnesota's Sentinel Lakes For Water Quality Monitoring, Andrew J. Dooley, Wondwosen M. Seyoum, Catherine M. O'Reilly

Faculty Publications - Geography, Geology, and the Environment

Traditional water quality monitoring methods often face limitations of equipment costs and labor demands, requiring innovative approaches to effectively assess the ecological health of inland lakes across vast areas. This research explores the application of free, publicly available water color chromaticity analysis for midcontinent lakes in Minnesota, USA. We examined water color variations in Minnesota’s Sentinel Lakes using Landsat 8 OLI data to analyze surface reflectance samples collected from the deepest area within each lake during the late summer, corresponding to peak annual insolation and trophic activity. The median dominant visible wavelength was used to characterize water color. Results indicate …

Hunting And Fishing Ceos: Environmental Plunderers Or Saviors?, Thomas Covington, Steve Widler, Keven Yost

Finance Faculty Works

CEOs who participate in hunting and fishing benefit by appreciating natural environments and permanently consuming natural resources. We examine whether CEOs who hunt and fish make different environmental decisions and find that firms led by CEOs who obtain the most hunting and fishing licenses have lower environmental performance as measured by MSCI-KLD. This effect is strongest in the environmental category of climate change but also extends to pollution, waste, and the protection of natural capital. Furthermore, firms led by CEOs with the most hunting and fishing licenses are significantly more likely to pay a regulatory settlement for an environmental regulatory …

Development And Evaluation Of Machine Learning Models For Early Pediatric Sepsis Prediction, Ancita M. Andrade

Browse all Theses and Dissertations

Sepsis is a leading cause of pediatric mortality, claiming more lives in the United States annually than all childhood cancers combined. Early identification in Emergency Departments (EDs) remains challenging, as the current Phoenix criteria establishes an updated international consensus definition for sepsis, however is not designed for use as a screening tool. This study aimed to develop predictive models identifying pediatric patients at risk of sepsis within 24 hours of admission. Multiple tree-based and deep learning models were trained utilizing clinical and laboratory data from the initial four hours of presentation. Both the LightGBM and LSTM architectures demonstrated superior performance, …

Computational Assessment Of Vitrimers Self-Healing For Renewable Energy And Aerospace Structures, Walaaeldin Mohamed Ahmed Derbala

Browse all Theses and Dissertations

Self-healing polymers, particularly vitrimers, are emerging as promising candidates in the development of advanced materials for renewable energy and aerospace structures. These materials exhibit dynamic covalent bond exchange mechanisms that enable reprocess ability, damage repair, and extended operational lifetime under harsh conditions. This study presents a density functional theory (DFT)-based computational investigation of the mechanistic pathways and energetics of bond exchange reactions in model vitrimer systems. We explore transition states, energy barriers, and thermodynamic features corresponding to associative and dissociative self-healing reactions in vitrimers. The study focuses on Diaminodiphenyl disulfide (AFD), a bifunctional molecule composed of two para-substituted aminophenyl rings …

Development And Application Of Gpu Based Monte Carlo Simulation Techniques In Radiation Medicine, Satzhan Sitmukhambetov

Physics Dissertations - Archive

Cancer remains a significant public health challenge, with treatments like radiation therapy forming a cornerstone of modern care. To address this challenge, advanced computer simulations can improve radiotherapy in two primary ways. From one hand, mechanistic simulations help elucidate the fundamental radiobiological working principles, which could contribute to the clinical advancements from a bottom-up framework. On the other hand, modality simulations could help design better clinical systems with better detection and therapeutic capabilities. This research enhances these critical simulation tools by introducing two significant developments.

First, this work introduces a metaphase DNA model into a microscopic Monte Carlo simulation framework …

Polarimetric Capture And Differentiable Rendering, Katherine Anne Salesin

Dartmouth College Ph.D Dissertations

Many scientific fields rely on the capture and modeling of light to extract underlying information about the world. Often, more information can be extracted by capturing more about the nature of the light, such as its spectral shape or polarization state. While polarization is a relatively unexplored topic in computer graphics, when used in tandem with other recent advancements in the field it has enormous potential to improve both forward and inverse models in other scientific disciplines. We demonstrate this potential in two distinct settings in this thesis.

First, we apply the capture of polarized light to an inverse problem …

Reducing Operator Training Time Through Virtual Reality: A Case Study On The Lpkf Protomat E44 Machine, Joshua C. Patel

Browse all Theses and Dissertations

This thesis presents the development of an immersive virtual reality (VR) simulation that replicates the operation of the LPKF ProtoMat E44 PCB milling machine. Aimed at reducing operator training time and improving procedural understanding, the simulation offers an interactive and realistic environment where users can safely engage with machine workflows and start-up sequences. The emphasis is on accurate representation, usability, and maintaining immersion to support intuitive learning. Although formal evaluation is outside the scope of this work, the system is designed to serve as a foundation for cost-effective, scalable training in technical and manufacturing contexts, offering a modern alternative to …

Generative Adversarial Networks (Gans) For High-Dimensional Biological Data, Harigovind Harikumar

Browse all Theses and Dissertations

This thesis investigates the application of Generative AI models, mainly Generative Adversarial Network (GAN) models to high dimensional and low sample size biological datasets like Motion Sickness, Breast Cancer, Crohn, and Melanoma. We utilized and compared three generative AI frameworks: Vanilla GAN, Wasserstein GAN (WGAN), Locality-Sensitive Hashing GAN (LSH-GAN) and Omics GAN. To address the challenges associated with high-dimensionality and low sample size, which was leading to very poor outputs of biological synthetic samples, we came up with an approach to stop the model when it reaches its saturation level. That is, we printed the loss plots to see where …

Great Lakes And Its Regional Climate In The Future, Miraj Bhakta Kayastha

Dissertations, Master's Theses and Master's Reports

The overarching objective of this dissertation is to enhance our predictive understanding of the Great Lakes regional climate by utilizing advanced modeling techniques and provide comprehensive insights into the future of the Great Lakes. This dissertation focuses on four areas pertinent to the future of the Great Lakes hydroclimate and extreme events, beginning with the derivation of robust water level projections for the Great Lakes in Chapter 2. Using a regional climate modeling system with a two-way coupled three-dimensional (3D) hydrodynamic lake and ice model for the Great lakes, we analyze long-term future changes in the over-lake precipitation, lake evaporation, …

Comparative Efficacy Of Hallucinogens In Treating Mood Disorders Through A Meta-Analysis Of Symptom Reduction, Dosage, And Duration, John Marco D.F. Muniz

Honors Undergraduate Theses

Background: Hallucinogens including psilocybin, lysergic acid diethylamide (LSD), ketamine, N,N-dimethyltryptamine (DMT) (as ayahuasca), have re-emerged as potential rapid-acting treatments for mood disorders. We conducted a meta-analysis of placebo-controlled trials evaluating their efficacy in depression and anxiety disorders. Methods: A systematic review identified 12 trials (Total ≈ 670) meeting inclusion criteria (randomized, placebo-controlled). Data on Cohen’s d and Hedges’ g effect sizes for depression- and anxiety-related outcomes were extracted. We computed pooled effect sizes (weighted by sample size and inverse variance), performed subgroup analyses by drug, diagnosis, follow-up duration, and outcome measure type, and assessed heterogeneity (I², Q …

Role Of C4 Resources In Isotopic Variability In Diet Among Children From Kellis 2 Cemetery, Dakhleh Oasis, Egypt, Faith R. Hendrix

Honors Undergraduate Theses

Using stable carbon isotope analysis, this study investigates dietary diversity in children buried at the Kellis 2 Cemetery (c. AD 50–450) in Egypt's Dakhleh Oasis. From the analysis of δ¹³C isotope values in hair keratin and bone collagen, the study reconstructs short-term and long-term dietary signals in juvenile and adult subjects. The aim is to clarify the role of C₄ plants—particularly millet—in weaning and childhood diets in a Romano-Christian Egyptian village context. A total of 631 segmented hair and 54 bone collagen samples were analyzed from 127 juveniles and 97 adults. Juvenile individuals (i.e., under 15 years biological age) showed …

Biomechanics Of The Atherosclerotic Lipidome: (Un)Expected Statin Interactions And Membrane Remodelling, Ethan M. Fong

Pomona Senior Theses

Statins interact with lipid membranes in ways that shape their pharmacokinetics, off-target effects, and pleiotropic actions, yet these interactions' mechanical and biophysical consequences remain poorly understood. This thesis employs a combination of surface plasmon resonance (SPR), quartz crystal microbalance with dissipation monitoring (QCM-D), and rheological modelling to characterize how representative statins intercalate within biomimetic supported lipid bilayers (SLBs) of healthy and diseased composition. SPR reveals that lipophilic statins exhibit higher apparent affinities and slower dissociation kinetics, especially in cholesterol- and anionic lipid-rich membranes. QCM-D analyses demonstrate that statins alter membrane mass, dissipation, and interfacial stiffness in a statin- and membrane-dependent …

The Tyrant King Of The Auction House: The Disastrous “Fine Artification” Of The Dinosaur, Amelia C. Kolstad

Anthós

This article examines how fine art auctioneers market dinosaur fossils as art pieces to wealthy collectors, depriving the paleontological field of specimens for scientific research. Drawing from recent examples of fossils sold at fine art auctions, this article notes how rising auction prices for specimens as ‘art’ prevent museums and research institutions from acquiring specimens for research and restoration. Kolstad concludes that the art auction houses’ marketing of fossils as art is detrimental to paleontological research. To protect fossils and their scientific value, Kolstad proposes alternatives, such as selling replicas to collectors and highlighting the importance of original specimens for …

A Critical Juncture: The Convergence Of Natural Resource Management And Tribal Sovereignty, Anna Aleta Butterfield

Graduate Student Portfolios, Professional Papers, and Capstone Projects

This portfolio reflects the work I’ve done in my four years as a dual degree student, pursuing a Master of Science in Environmental Studies and a juris doctorate degree, and focuses on policies and laws surrounding natural resource management. It touches on how those policies relate to and expand or constrict the exercise of sovereignty by indigenous populations.

This piece first considers the effects of plastic on salmon populations and those indigenous groups that rely on salmon for subsistence and cultural purposes. The remaining three pieces focus on various aspects of the Confederated Salish and Kootenai Tribes - Montana Water …

Congestion Mitigation For Foraging Robot Swarms Using Spiral Path Strategies, Arturo Gonzalez, Qi Lu

Computer Science Faculty Publications

Swarm robotics offers robust and scalable solutions for tasks such as foraging, but congestion near central collection zones remains a critical challenge, especially with increasing swarm sizes. Traditional solutions, such as static path planning or local repulsion-based methods, often fail to prevent interrobot collisions or bottlenecks near the collection zones. This research presents a comparative study of three strategies to mitigate congestion when returning resources to the central collection zone. The research herein focuses on tightly packed environments where, in theory, robots should follow a preplanned spiral, either ad-hoc, square, or circular, with congestion detection as described in the first …

Robust Mitigation Strategy For Misleading Pheromone Trails In Foraging Robot Swarms, Ryan Luna, Qi Lu

Computer Science Faculty Publications

This study advances the security of swarm robotics by examining the resilience of stigmergic communication in foraging robot swarms against deceptive strategies. We specifically investigate the swarm’s vulnerability to attacks via misleading pheromone trails laid by detractor robots, which significantly hinder foraging performance. Through simulations, we evaluated the adverse effects of such attacks on resource collection and forager capture rates, highlighting a notable decline as the percentage of detractors increases. To counter these threats, we implement a robust defense mechanism utilizing DBSCAN for density-based clustering of pheromone trails, complemented by a cluster grouping method that effectively isolates batches of detractors …

Macroinvertebrate Communities And Food Web Structure In Tundra Streams Are Shaped By Substrate Size And Beaver Impoundments, Mathew K. Mervyn

Theses and Dissertations (Comprehensive)

North American beavers (Castor Canadensis) are expanding their range into the Arctic tundra as climate change drives earlier ice and snowmelt, and increased shrub cover. As ecosystem engineers, beavers build dams that alter water chemistry by creating impoundments within streams, trapping sediment and organic matter, and modifying nutrient cycling. This thesis evaluates how beaver impoundments interact with natural geomorphic variation in tundra streams and how impoundments affect tundra freshwater ecosystems in the western Canadian Arctic.

In Chapter 2, I compared water chemistry and benthic macroinvertebrate (BMI) community composition across 16 stream reaches, including those with and without beaver dams, with …

Crime Modeling Using An Integrated Cnn–Lstm Architecture With Embedded Self-Excitation, Pawandeep Kaur

Theses and Dissertations (Comprehensive)

It is often assumed that natural phenomena occur randomly over time. However, careful analysis reveals that these events typically form some series or sequences and exhibit distinctive temporal patterns. These patterns are not exclusive to nature. They also appear in human activities, often studied under the concept of bursty human dynamics. The statistical methods analyzing bursty human dynamics not only capture overall trends or seasonality but also explore how past events influence future ones. It makes the analysis more realistic and the results more closely aligned with reality. Bursty human dynamics can be studied at two levels: the individual level …

Heterotrophy Of Particulate Organic Matter Subsidies Contributes To Divergent Bleaching Responses In Tropical Sclaractinian Corals, Connor R. Love, Kelly E. Speare, Michael D. Fox, Veronica Z. Radice, Kelton W. Mcmahon, Gretchen E. Hofmann,, David L. Valentine, Marie E. Strader

Biological Sciences Faculty Publications

Heterotrophic feeding on plankton and particulate organic matter (POM) by tropical Scleractinian corals is known to aid in the resistance and recovery from thermally induced bleaching. However, the relative importance of heterotrophy in promoting bleaching resistance and recovery is likely to vary based on ecological context and the severity of heat stress. In 2019, the Pacific Island of Mo'orea experienced mass coral mortality during a widespread marine heatwave. Many Acropora hyacinthus colonies on the shallow reef slope (5 m) were resistant to bleaching, while colonies on the deeper fore reef (14 m) often bleached and subsequently recovered, despite similar thermal …

Analyzing Microbial Communities In Porites Astreoides, Sanaa Caldwell, Katie Parker, Daniel Barshis

Biological Sciences Faculty Publications

Coral reefs are vital marine ecosystems that support many different species and ecosystem services through protecting coastlines from storms and erosion, providing raw materials for medication, and facilitating diversity amongst marine species. Anthropogenic climate change is causing ocean temperatures to exceed the range of coral thermal tolerance resulting in more coral bleaching events globally. However, some corals have the capacity to withstand high temperatures through different thermal tolerance strategies. A balanced microbial community plays a critical role in coral health and recent studies have indicated that a balanced microbiome is associated with temperature-stress tolerant corals. Yet, there is a severe …

Thermal Tolerance Limits Of Mesophotic Corals In American Samoa, Daniel Barshis, Veronica Z. Radice, Katherine E. Parker, Nicholas Evensen

Biological Sciences Faculty Publications

We analyzed the thermal tolerances of multiple coral species from an upper mesophotic (38–40m) and a shallow reef (5–10m) with our portable Coral Bleaching Automated Stress System (CBASS). Depth generalist Montipora grisea (deep and shallow) and depth specialists Pachyseris speciosa and Leptoseris sp. (deep only) were assayed from Leone, located on the western coast of Tutuila in American Samoa. Fragments from 10 genotypes of each species were exposed to a 17-hour thermal stress assay reaching four maximum temperatures ranging from 30–38°C under in situ light conditions (150 μmol photons m⁻² s⁻¹ under a Lee Filters “deep …

A Multispecies, Multisite Assessment Of Coral Thermal Tolerances In American Samoa, Using Acute Heat Stress Assays, Ponchanok Weeriyanun, Nicolas R. Evensen, Katherine E. Parker, Veronica Z. Radice, Daniel J. Barshis

Biological Sciences Faculty Publications

Reef-building corals are being impacted by increasing seawater temperatures, with marine heatwaves leading to mass bleaching events and extensive mortality. However, corals can display variation in thermal tolerance, both within and among species. In this study, we sampled four coral species (Acropora hyacinthus, Montipora grisea, Pocillopora verrucosa, and Porites lobata) from two sites on Tutuila, American Samoa, with contrasting environmental regimes but similar Maximum Monthly Means (MMM). Coral fragments were subjected to short-term acute heat stress experiments using the Coral Bleaching Automated Stress System (CBASS). PAM Fluorometry was used to measure the symbiont’s effective quantum yield (Fv/Fm) following heat stress …

Low Salinities Impair Heat Tolerance And Alter Reproductive Traits With No Implications For Survival In A Marine Annelid From Coastal Habitats, Gabrielle Newton, Gloria Massamba-N'Siala

Biological Sciences Faculty Publications

Climate change is expected to intensify salinity and temperature fluctuations in estuarine and coastal habitats. However, the impact of salinity variation on ectotherms’ thermal tolerance remains underexplored, limiting our understanding of the interplay between these stressors. This study investigated salinity-dependent changes in life history traits (survival, growth rate, fecundity, and egg size) over a 33-day exposure to a salinity gradient (12, 17, 22, 27, 32, 35, 40, 45, 50) in the marine annelid Ophryotrocha labronica. Individuals that survived the salinity treatments were assessed for their upper and lower thermal tolerance limits. Female individuals, the target of the study, exhibited …

Investigating The Relationships Between Biotic And Abiotic Factors Affecting Migratory Behavior In Westslope Cutthroat Trout Within The Pend Oreille System, Garrett M. Duncan

EWU Masters Thesis Collection

Salmonids express several different life histories from migrating to oceans and back or staying in their natal streams as a resident. Migratory individuals are a vital part of the overall success of populations due to the potential for increased genetic diversity and increased fecundity they offer over resident individuals. This research was completed in three basins including Priest River, Pack River, and Lightning Creek which are all connected to the Pend Oreille Basin and are important producers of Westslope Cutthroat Trout (Oncorhynchus clarkii lewisi). Thirty-nine sites were sampled between the three basins. Results were compared between these tributaries that have …

Understanding The Influence Of Image Enhancement On Underwater Object Detection: A Quantitative And Qualitative Study, Ashraf Saleem, Ali Awad, Sidike Paheding, Evan Lucas, Timothy C. Havens, Peter C. Esselman

Michigan Tech Publications

Underwater image enhancement is often perceived as a disadvantageous process to object detection. We propose a novel analysis of the interactions between enhancement and detection, elaborating on the potential of enhancement to improve detection. In particular, we evaluate object detection performance for each individual image rather than across the entire set to allow a direct performance comparison of each image before and after enhancement. This approach enables the generation of unique queries to identify the outperforming and underperforming enhanced images compared to the original images. To accomplish this, we first produce enhanced image sets of the original images using recent …

Giving Props To Soil Property Predictive Models: Utilizing Mir To Predict Soil Health Properties, Diala M. Abboud

Theses and Dissertations--Plant and Soil Sciences

Soil health is critical to sustaining life on Earth, influencing plant growth, agricultural productivity, water quality, and overall ecosystem sustainability. In response to climate change and intensifying land use, the need to improve our understanding of soil health has become increasingly urgent. The application of mid-infrared (MIR) spectroscopy coupled with statistical modeling has emerged as a promising, cost-effective approach to predict soil health parameters, offering a quicker alternative to traditional wet chemistry analyses. MIR methods have been successfully applied to predict various soil health properties, such as bulk density (BD), cation exchange capacity (CEC), base saturation (BS), electrical conductivity (EC), …

Microbial Community Stabilization By Restored Oyster Reefs: Implications For Blue Carbon Storage, Natalie Boydstun

College of Graduate Studies: Theses & Dissertations

Coastal ecosystems provide critical carbon sequestration services, yet the microbial mechanisms underlying carbon storage remain poorly understood, particularly in non-vegetated habitats. This study investigated whether restored oyster reefs (Crassostrea virginica) enhance sediment carbon storage potential by stabilizing microbial communities and promoting efficient organic matter processing. I hypothesized that reef-mediated sediment stabilization and organic deposition would create conditions favoring microbial degradation of complex carbon compounds into stable soil organic matter, ultimately supporting anaerobic carbon storage. To test this, I compared sediment biogeochemistry, enzyme activity, and microbial community structure between three restored oyster reef sites and two unstructured control sites …

Numerical Simulation Of The Fracture Resistance Of A Flame Deflector Under Impact And High Temperature By Using The Extended Finite-Element Method, Guangzhong Liu, Yuqing Feng, Tong Lin, Zhixin Xiong, Zhenting Chen

Journal of Marine Science and Technology–Taiwan

During the launch of rockets at sea, the flame deflector of the launch platform is subject to transient impact loads and high temperatures, which can result in the fracturing of the flame deflector, thereby endangering the platform and launch safety. In this study, dynamic crack propagation in a flame deflector under the aforementioned conditions was numerically investigated using the extended finite-element method (XFEM). The bulk of the flame deflector was modeled using shell elements, the local area in which the crack evolves was modeled using solid elements, and discontinuities were modeled using enrichment functions in the XFEM. The degrees of …

Application Of Genetic Algorithm In Container Vessel Stowage Planning With Carbon Tax Considerations, Ming-Feng Yang, Wei-Hao Su, Ko-Meng Hu, Yu-Hsuan Li

Journal of Marine Science and Technology–Taiwan

This study developed a method for optimizing stowage planning for container vessels, a crucial aspect of international trade logistics. Over 80% of global trade depends on containerized transportation; thus, effective stowage planning is essential for minimizing transportation costs and enhancing operational efficiency. In the proposed hybrid optimization approach, integer programming is combined with a genetic algorithm to generate optimal stowage plans. The key factors considered in this method include load capacity limits, stacking constraints, and carbon tax regulations. The proposed method involves maximizing space utilization while minimizing logistics costs, with particular emphasis on reducing port dwell times. The findings of …

Research On Multi-Ship Collision Avoidance Decision-Making Based On Improved Velocity Obstacle Method Using Dynamic Elliptical Ship Domains, Tang Xinwei, Li Weifeng

Journal of Marine Science and Technology–Taiwan

The velocity obstacle method offers collision avoidance solutions for critical multi-ship encounter scenarios. This thesis introduces a Reciprocal Velocity Obstacle (RVO) approach based on dynamic elliptical ship domains for multi-ship collision avoidance. Initially, the concept of dynamic elliptical ship domains is presented, building upon the original static elliptical ship domain Velocity Obstacle (VO) method. Subsequently, multi-ship encounter scenarios are simulated in both virtual environments and real nautical charts, comparing the two methods. The analysis results demonstrate the improved method's excellent performance in both cases, underscoring its advantages. This research provides more effective collision avoidance strategies for multi-ship encounters.