Digital Commons Network^™

Nickel Superalloy Composition And Process Optimization For Improved Weldability, Anna Cole

Dissertations, Master's Theses and Master's Reports

In order to improve the efficiency of advanced ultra-supercritical power plants, materials must be designed to maintain mechanical properties in high pressure and high temperature environments. Nickel superalloys are a viable option, but are expensive and are difficult to weld, leading to joint failures. The goal of this project is to experimentally evaluate computationally-designed nickel superalloys for increased weldability and decreased alloy cost, while maintaining mechanical properties. Two optimized nickel alloys were designed to these targets and compared to benchmark nickel superalloys. Both optimized alloys had lower cost, with a 5Co-4Ti alloy exceeding room temperature hardness and elastic modulus values, …

Direct Methane Capture Via Aerobic Methanotrophs, Waaseyaaban Landgren

Dissertations, Master's Theses and Master's Reports

Methane, a greenhouse gas with global warming potential 80 times greater than carbon dioxide, heavily contributes to global warming. Removing 1 Gt of atmospheric methane by 2050 would limit global temperature increase from reaching 1.5°C. Currently, biotrickling filter systems for removing atmospheric methane via methanotrophs exist, but not for very low methane concentrations (< 1 v%). Current research work at the University of Washington isolated and engineered a microbe strain which thrives at 500 ppmv methane, solving one obstacle in making this technology feasible. In this thesis, techno-economic analysis and environmental life cycle assessment conducted on this process have assessed its economic feasibility, greenhouse gas reduction potential, and possible areas of improvement. Study results show that at 500 ppmv methane, this process could remove atmospheric methane at a cost of $3,992-5,224 per tCH₄. The ideal case also produces annual net reduction in warming potential by 276-311 tCO₂e per process unit deployed.

Generalizing Medical Image Segmentation Task With Efficient Deep Learning Models, Abel A. Reyes-Angulo

Dissertations, Master's Theses and Master's Reports

Medical Image Segmentation is a critical task in the field of medical imaging, playing a crucial role in diagnostics, treatment planning, and disease monitoring. The emergence of Deep Learning (DL) has ushered in a new era in Artificial Intelligence (AI), propelling remarkable advancements in key domains like language translation, object recognition, and recommendation systems. This evolution has been accompanied by continuous enhancements in computational efficiency and improvements in predictive accuracy. The introduction of sophisticated algorithms, such as convolutional neural networks (CNNs) and transformers, exemplifies these advancements. DL algorithms have demonstrated exceptional efficacy in medical image segmentation tasks, showcasing the potential …

Holistic Energy Efficiency Analysis Of Electrified Off-Highway Material Handler: From Drive Cycle Characterization To Powertrain, Hydraulic, And Thermal System Performance, Alexander Czarnecki

Dissertations, Master's Theses and Master's Reports

Three complexities surrounding the operation and testing of hybrid electric, heavy-duty nonroad machines have been addressed experimentally and using 1D simulation. Their resolutions have been intertwined with the development of a prototype machine that was proven to reduce fuel consumption in excess of 20%. A real-world drive cycle that leveraged hydraulic cylinder position was developed and utilized to ensure accurate reproduction of hydraulic work between the baseline and hybrid machines, while simultaneously maintaining less than 5% RMS error in position for main load handling functions. The newly developed, machine-specific drive cycle also contributed towards making equivalent comparisons in energy consumption …

Design And Control Of Reversible Adhesion: Switchable Adhesive Molecules And Electrochemical Approaches, Kan Wang

Dissertations, Master's Theses and Master's Reports

Smart adhesives are materials that can reversibly gain or lose adhesion in response to external stimuli such as temperature, pH, electric fields, or light. Their switchable and temporary adhesion makes them highly promising for applications in wound healing, manufacturing, and robotic locomotion. Among them, catechol-based polymers have been widely studied for pH- and electro-responsive adhesion, due to their reversible non-covalent crosslinking. However, their performance is limited by irreversible covalent crosslinking reactions and the need for conductive surfaces in electrochemical systems. While boronic acid has been used to protect catechol, its reversibility remains limited. Therefore, new adhesive molecules and system designs …

Performance And Environmental Impact Of Waste Glass Asphalt In Cold Regions, Kai Xin

Dissertations, Master's Theses and Master's Reports

The reuse of waste glass in asphalt mixtures has significant potential in sustainable pavement engineering, yet its performance under cold, freeze–thaw conditions remain underexplored. This dissertation presents a first-of-its-kind comprehensive evaluation of glass asphalt for cold regions, simultaneously assessing its low-temperature cracking resistance, moisture susceptibility, field performance, and life-cycle environmental impacts. A series of laboratory tests were performed on asphalt mixtures incorporating various proportions of crushed waste glass aggregate, including Disk-Shaped Compact Tension (DCT) and Indirect Tensile (IDT) tests for low-temperature fracture resistance, and Tensile Strength Ratio (TSR) and Hamburg Wheel Tracking (HWTT) tests for moisture damage and rutting susceptibility. …

Estimating Unconfined Compressive Strength (Ucs) Of Rocks From Measurement While Drilling (Mwd) Data, Can Erdem

Dissertations, Master's Theses and Master's Reports

Measurement-while-drilling (MWD) technology enables the real-time monitoring of drilling parameters during the drilling process. MWD data can provide valuable insight into the mechanical behavior of intact rocks and rock masses, which is essential for geotechnical applications such as foundation design and underground construction. The aim of this study is to correlate real-time drilling parameters, recorded using a laboratory-developed MWD system, with the unconfined compressive strength (UCS) of rocks. A custom laboratory MWD system was designed to simultaneously record four key drilling parameters: thrust (axial force, crowd), torque, penetration rate, and rotational speed. The custom-built MWD system was used to continuously …

Microbial Hydrocarbon Degradation And Carbon Cycling In Marine And Freshwater Sediments: A Comparative Metagenomic Analysis, Yogita M. Warkhade

Dissertations, Master's Theses and Master's Reports

Microbes are essential in keeping our environment balanced, especially by fixing carbon dioxide and breaking down hydrocarbons in aquatic sediments. This thesis explores how microbial communities perform these tasks in different sediment environments, including marine areas (Caspian Sea and Mediterranean Sea) and freshwater ecosystems (Great Lakes). The first part of this thesis reviews current knowledge about how microbes degrade hydrocarbons. It highlights the importance of different pathways microbes use depending on oxygen availability. The second part provides a detailed study of the microbial communities found in marine sediments from the Caspian Sea and Mediterranean Sea, showing that microbes in these …

Dam It All: A Multi-Scalar Investigation Into The Ecological Role And Function Of Beaver Dams, Kenneth Larsen

Dissertations, Master's Theses and Master's Reports

The central theme of this dissertation is ecological scaling, which examines how small, localized features, such as beaver ponds, contribute to large-scale watershed processes and how different modeling approaches at various scales reveal distinct insights. Through a combination of probabilistic modeling and high-resolution empirical research, this work demonstrates that small ponded systems, particularly those created by beavers (Castor canadensis), serve as critical biogeochemical control points, whose contributions to sediment and nutrient dynamics have been historically underestimated.

In Chapter 1, I contextualize this research within the broader fields of freshwater ecology, watershed modeling, and ecological restoration. I introduce the …

Innovations In Balanced Mix Design: Establishing Gwp Thresholds For Various Nmas And Evaluating Superpave Vs. Bmd In High Content Rubber Asphalt, Kai Xin

Dissertations, Master's Theses and Master's Reports

Traditional volumetric asphalt mix design methods, such as Superpave, frequently struggle to address critical performance parameters, leading many agencies to seek more robust approaches. Balanced Mix Design (BMD) has emerged as a forward-looking alternative by directly measuring rutting and cracking resistance in the laboratory. In this study, BMD principles were applied to asphalt mixtures featuring three distinct NMAS mixes and two high content rubber mixes, introduced through both dry and semi-wet processes. Compared with conventional volumetric constraints, BMD provided greater flexibility in adjusting binder content and gradation to accommodate elevated crumb-rubber levels. The resulting mixtures satisfied both rutting and cracking …

Method For Assessing Gasoline Powered Internal Combustion Engine Exhaust Accumulation When Idling In Enclosed Space By Automatic Shut Off, Eamon Mcclintock

Dissertations, Master's Theses and Master's Reports

About 120 fatalities/year are caused by Carbon Monoxide (CO) poisoning outside of the vehicle which can take place in the garage or attached house. A controlled test environment was created to mimic a garage with representative ventilation, volume, and instrumentation. Tests were performed with vehicles of varying engine displacement size using parameters tuned to replicate four scenarios of vehicle operation including vehicle start state, HVAC operation, and ambient temperature. A house model was built to model CO accumulation using realistic air exchange rates to simulate air transfer between the garage and attached house. Depletion of Oxygen (O2) in the garage …

Batteryless Nfc-Enabled Wireless Sensor Node: Design, Optimization, And Implementation, Rishin Patra

Dissertations, Master's Theses and Master's Reports

This thesis presents the design, construction, and testing of a batteryless Near-field communication (NFC) powered wireless sensor node intended for maintenance free, short range Internet of Things (IoT) applications. The work focuses on harvesting energy from a 13.56 MHz NFC field to power a very low-power sensing platform capa- ble of measuring temperature, pressure, and humidity without the use of batteries or wired power. The motivation behind this approach is the growing need for reliable, sustainable, and low-maintenance sensing systems that can operate in environments where battery replacement is impractical, undesirable, or environmentally costly. The prototype is built around a …

Indigenous-Industrial Heritage: Centering Indigenous Voices In Minnesota's Iron Range, Larissa A. Juip

Dissertations, Master's Theses and Master's Reports

Industrial heritage refers to the material remains, sites, landscapes, and practices associated with industrial and extractive activities. As a field, it has historically been concerned with the conservation, management, and interpretation of industrial sites and activities and forms a central narrative within Minnesota's museums. Yet such accounts often privilege object-centered narratives while silencing the presence, knowledge, and contributions of Indigenous and Descendant communities, obscuring their enduring relationships to extractive landscapes. In recent decades, critiques of traditional industrial heritage approaches have identified gaps in the discipline related to the exclusion of marginalized populations, including Indigenous Peoples. Minnesota is home to eleven …

Iron Ore Tailings Reprocessing By Electrostatic Separation Plus Two Stages Froth Flotation, Vincent Bailey Arohunmolase

Dissertations, Master's Theses and Master's Reports

The reprocessing of tailings is crucial for recovering valuable iron and reducing the environmental impact associated with tailings disposal. This study investigates the practicality of reprocessing tailings to enhance iron oxide content, combining electrostatic separation with a two-stage froth flotation process using oleic acid (direct flotation) and amine (reverse flotation). The primary goal is to efficiently recover valuable iron from tailings, thereby reducing waste and promoting sustainable resource utilization. The process aims to upgrade the iron oxide content to around 93-99% Fe₂O₃, making the recovered material suitable for the production of direct-reduced iron.

Electrostatic separation was …

Finding Antipatterns Across Languages With Abstract Syntax Trees, Daniel T. Masker

Dissertations, Master's Theses and Master's Reports

Finding antipatterns in student code is a difficult task that is useful for helping beginner programmers. Antipatterns are common mistakes that students make while writing code. Code critiquers are tools that find antipatterns and provide rich, immediate feedback to students, even when professors aren’t available. WebTA is a code critiquer that finds antipatterns using regular expressions (regex), error messages, and language-specific abstract syntax trees (ASTs). Each of these tools has obstacles to antipattern searching that are difficult to overcome. Regex is without context, limiting the patterns it can recognize. Additionally, even experienced users have difficulty reading and debugging regex. Error …

Effectiveness, Coherence, And Justice Implications Of Clean Energy Policies In The United States, Josephine Amponsem

Dissertations, Master's Theses and Master's Reports

Public policies have been adopted and implemented at various government levels in the United States, aiming to facilitate the clean energy transition process. This dissertation examines three distinct but related dimensions of clean energy policies: policy effectiveness, policy coherence, and distributional policy impact. First, I evaluate the impact of the American Reinvestment and Recovery Act (ARRA) on clean energy adoption at the utility level using a quasi-experimental design: the Difference-in-Difference estimation. Secondly, I use the state of California as a case study to investigate the role of policy coherence in public policy success. Thirdly, I investigate whether communities with different …

Bayesian Alloy Design With Additive Synthesis, Michael R. Sulwer

Dissertations, Master's Theses and Master's Reports

To reduce carbon emissions and increase power out, steam powerplants need to increase the operating temperatures and pressures of steam turbines to improve efficiency. This necessitates the development of high temperature alloys with superior strength and stability. This research aims to design a class of solid solution High Entropy Alloys (HEAs) to exceed the high temperature performance of commercial alloys like Haynes 230 while maintaining comparable costs for Advanced Ultra Supercritical (A-USC) steam cycles. This project integrates Bayesian optimization and Calculation of Phase Diagrams (CALPHAD) within an Integrated Computational Materials Engineering (ICME) framework to predict and optimize key material properties: …

Energy Transitions In Underserved Communities: Meaningful Engagement To Address Energy Burdens And Air Pollution, Nyasha Milanzi

Dissertations, Master's Theses and Master's Reports

This report presents two connected studies focused on environmental justice and community engagement in energy transitions. The first study examines engagement practices in EPA-funded projects using interviews and public abstracts. Applying the EngageINFEWS framework, it analyses stakeholder dynamics and offers recommendations for working with underserved communities. Key insights include addressing power imbalances, securing funding, building capacity, and fostering communication. The second study centres on the REJuST project, which supports energy justice in a rural northern community impacted by public health concerns linked to a bioenergy facility burning wood, paper, plastics, and tire-derived fuels. I use survey data to explore resident …

Phase-Field Method Of Fracture In Fiber-Reinforced Polymer Composites: Theory, Modeling, And Validation, Akash Kumar

Dissertations, Master's Theses and Master's Reports

Fiber-reinforced polymer composites (FRPCs) are widely used in aerospace, automotive, and civil engineering due to their high specific strength, stiffness, and durability. However, their anisotropic and heterogeneous nature makes fracture prediction challenging, with damage modes classified as intralaminar failure (matrix cracking, fiber breakage, fiber-matrix debonding) and interlaminar delamination. Delamination, driven by weak through-thickness strength and high interlaminar stresses, is a predominant failure mechanism in FRPCs. While cohesive zone models (CZMs) are commonly used for delamination, they are computationally expensive and inefficient for capturing intralaminar fractures where crack paths are unknown. To address this, we developed a unified phase field-based cohesive …

Molecular Modeling Methods And Applications For Accelerating Polymerization And Pyrolysis Studies, Joshua D. Kemppainen

Dissertations, Master's Theses and Master's Reports

Polymer matrix composites and carbon-carbon composites play critical roles in the aerospace, automotive, and construction industries. Different matrix materials and processing conditions can lead to a large variety of composite materials and composite properties. Integrated computational materials engineering has been used to tailor PMC matrix materials and processing conditions to specific properties and manufacturing techniques. The integrated computational materials engineering process modeling framework uses molecular dynamics at the nanometer length scale to characterize the evolving thermo-mechanical properties of the polymer as it cures. Then finite element analysis is used at the micrometer length scale to adjust cure cycles to tailor …

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, …

Distributing Composition: Rhetorical Agency In First-Year Writing, Elizabeth Novotny

Dissertations, Master's Theses and Master's Reports

This project centers on engaging students in class lessons related to rhetorical agency. Typically understood as the capacity to act, within rhetoric, I define agency as the capacity to make meaning. In most traditional Western conceptions, agency is primarily located with the individual rhetor. However, these views were increasingly challenged throughout the later twentieth century as theorists from various traditions came to understand that discussing our agency as solely our own doing was insufficient. In contrast to an individualistic understanding of agency, theories that characterize rhetorical agency as more fragmented have evolved, where, instead of writing and rhetoric being …

From Plasmonics To Superfluorescence: Engineering Light- Matter Interactions For Quantum Optical Phenomena, Aaron J. Wildenborg

Dissertations, Master's Theses and Master's Reports

This work presents different ways to engineer light-matter interactions by using nanostructures to exploit quantum-optical phenomena. First, sodium (Na) is predicted to be an ideal plasmonic material due to its ultra-low optical losses from the visible to the near-infrared (NIR). However, Na has practical limitations due to its high chemical reactivity. Using a scalable fabrication method for Na plasmonic nanostructures by combining phase-shift photolithography and a thermo-assisted spin-coating process, we produced nano-pit arrays of varying periodicities (300-600 nm), supporting tunable surface plasmon polariton (SPP) modes spanning visible to NIR. These structures demonstrated SPP resonances as narrow as 9.3 nm, with …

Linear Response Of Driven Non-Hermitian Photonic Systems, Lucas R. Simonson

Dissertations, Master's Theses and Master's Reports

The notion of non-Hermitian engineering in optics and photonics has attracted considerable attention in the past decade. From laser devices and sensing applications to light trapping and guiding, non-Hermitian engineering provides additional degrees of freedom that allows for more control over light-matter interaction. It is thus of great importance to develop a deep insight into the linear response of non-Hermitian optical systems. We begin by studying the linear response of non-Hermitian Hamiltonian systems under general conditions and derive an expression for its Green's operator in terms of its eigenvectors and its canonical Jordan vectors. Next, we investigate the quantum noise …

Ansi Z97 Impact Testing Of Thin Glass, Justin P. Anthony

Dissertations, Master's Theses and Master's Reports

To determine whether thin glass constructions can pass Z97 impact test to qualify as safety glass an extensive protocol was performed. Constructions including monolithic, chemically strengthened, filmed, laminated, and triple pane insulated glass units comprised of thin glass ranging in thickness between 0.50 mm and 1.6mm were evaluated. Test results indicate annealed specimens, and laminated specimens performed similar to constructions with 3 mm and 6 mm glass. Specimens with 0.2 mm film consistently performed as safety glass for thicknesses between 0.7 mm and 1.6 mm and similar performance for specimens with 0.1 mm film with thickness of 1.1 mm and …

Proximal Seismic Tracking Of Pyroclastic Density Currents At Volcán De Fuego, Guatemala, Jacob A. Krier

Dissertations, Master's Theses and Master's Reports

Pyroclastic Density Currents (PDCs) are deadly flows of ash, tephra, gas, and solidified magma which predominantly occur when an ash plume collapses during a volcanic eruption. PDCs are also able to form when large deposits of ash at the summit of a volcano are displaced during an eruption and flow downslope. This is typically the mechanism behind PDCs that occur at Volcán de Fuego such as one that occurred in 2018 killing at least 430 people. The purpose of this paper is to track the propagation of PDCs that occurred at Fuego seismologically in order to better understand how they …

Knowledge Integrated Deep Learning For Enhanced Fault Diagnosis And Prognosis For Rotating Machinery And Its Applications On Marine Systems, Yunsheng Su

Dissertations, Master's Theses and Master's Reports

This dissertation develops a knowledge-informed deep learning framework for robust fault diagnosis and prognosis across various engineered systems, including bearings, lithium-ion batteries, and mooring systems in wave energy converters (WECs). A deep transfer learning (DTL) method is first developed to improve bearing fault diagnosis by fusing data from multiple sources and extracting key features using convolutional neural networks (CNNs). Building upon this, a knowledge-informed deep network (KIDN) framework is proposed, integrating physics-based features with deep learning to enhance diagnostic accuracy and generalizability. A constrained Gaussian process (CGP) model is further employed to guide adaptive network design and reduce model tuning …

Developing A Graphql Mesh Federated Api Gateway: Rapid Integration Of New Endpoints Into A Predefined Schema, Noah Kolczynski

Dissertations, Master's Theses and Master's Reports

The Navy’s Undersea Warfare Decision Support System (USW-DSS) uses data from an ever growing number of sensors, accessible through an equally growing number of Application Programming Interfaces (APIs). Due to the lack of standardization among these sensors and APIs, as the system has continued to grow, the challenge of collecting and using these data has become increasingly prevalent. Previous work at Michigan Tech, in collaboration with engineers at ARiA (Applied Research in Acoustics LLC), introduced a GraphQL Mesh federated API gateway. The gateway would enable the combination of diverse API sources into a predefined hierarchical structure. This report follows the …

Life Cycle Assessment And Techno-Economic Analysis Of Mine Tailings As A Sustainable Raw Material For Mineral Carbonation And Recovery Of Critical Minerals, Vida Amankwaa

Dissertations, Master's Theses and Master's Reports

This study assesses the feasibility of using mine tailings for mineral carbonation and nickel recovery through a comprehensive Life Cycle Assessment (LCA) and Techno-Economic Analysis (TEA). The LCA quantifies greenhouse gas emissions, energy use, and resource consumption, while the TEA evaluates capital investment, operational costs, and process efficiency. The conventional beneficiation process at Eagle Mine serves as a baseline, highlighting its environmental footprint and operational costs. Results indicate that tailings reprocessing incurs higher costs ($34.76 per tonne of tailings processed) compared to conventional ore processing ($25.90 per tonne) due to increased energy consumption and material handling requirements. Additionally, several mineral …

Computational Tools For Protein Classification In Metagenomes, Fawad Ullah

Dissertations, Master's Theses and Master's Reports

Advances in genomic sequencing have dramatically increased the amount and the speed at which genomic data is being generated. These technological advances have enabled the ability to profile the genetic information of organisms and communities at unprecedented scales. Many methods have been developed to identify and classify genes within these datasets. However, many generic pipelines for gene annotation struggle to accurately predict specific protein classes that may not be represented in their databases. Two major challenges exist for classification of specific protein classes in metagenomic databases. The first is the fact that many metagenomic assemblies are highly fragmented with many …