Engineering Commons^™

A Proposed Metals Recovery Assessment Protocol To Evaluate Mine Waste For Critical Minerals And Rare Earth Recovery Prior To Site Remediation, Claire Mbia

Graduate Theses & Non-Theses

The Metals Recovery Assessment (MRA) protocol involves collecting and evaluating information to assess the possibility for recovery of critical or rare earth minerals at mine sites to offset remediation or redevelopment costs associated with land reuse at Superfund or closed mine sites. This protocol provides a tool to implement metals recovery in conjunction with property reuse, and may involve a review of available records, visual inspections of the site, sample collection and discussions with local government officials and community members. The selection for metals recovery would be intended to both achieve metals reduction which may be required for the protection …

Unraveling The Impact Of Vessel Geometry In Resonant Acoustic Mixing, Jefferson Guthrie

Graduate Theses & Non-Theses

This study aimed to advance the understanding of ResonantAcoustic® Mixing (RAM) and its application in industrial powder processing. RAM, which consists of vertically oscillating boundaries operating at nominally 60 Hz with accelerations up to 100 g’s, is particularly effective for mixing fine powders and materials. RAM is able to complete mixing processes 10 to 100 times faster than traditional methods without the risk of cross contamination. Despite RAM’s growing potential, the underlying mechanisms of RAM are not fully understood, limiting its optimization and broader adoption. Research in this study sought to bridge existing gaps in understanding by investigating the influence …

Biogenic Synthesis Of Metallic And Bimetallic Oxide Nanoparticles For Water Treatment Applications, Gunarani G.I

Theses and Dissertations

Access to clean water is a quality-of-life indicator. The availability of clean water apart from water scarcity is marred due to contamination by heavy metals and synthetic dyes, posing a grave environmental and public health challenge. This necessitates the implementation of advanced and sustainable treatment solutions towards water remediation. This research work focusses on the fabrication and application of biogenic and chemically synthesized metallic and bimetallic nanoparticles for the efficient removal of uranium, chromium, and toxic dyes from aqueous environments. The study particularly focuses on zero-valent (C-Fe and B-Fe) and bimetallic (C-NiFe and B-NiFe) nanoparticles, evaluating their adsorption capabilities and …

Rare Earth Mineral Flotation – A Comparison Of Silicates To Oxides, Carbonates And Phosphates, Abdul Mamudu

Graduate Theses & Non-Theses

Flotation is a processing method used to separate valuable minerals from gangue minerals based on differences in hydrophobicity. When applied to ores bearing rare earth minerals (REMs) variations in rare earth element (REE) concentrations within the REMs can lead to inconsistent flotation results. Prior work at Montana Technological University examined the adsorption of collectors on the surfaces of synthetic REMs to assess recovery via flotation. Previous studies showed that the results obtained for Salicyl Hydroxamic Acid (SHA) on rare earth oxides REO), rare earth carbonates (REC), and rare earth phosphates (REP) vary depending on the coordination number (CN) and the …

Characterization Of A Magnetically Contained Hot Filament Plasma Source With A Wide-Sweeping Langmuir Probe, Jonas Rowan

Doctoral Dissertations and Master's Theses

Ionospheric plasma research in the Space and Atmospheric Instrumentation Laboratory’s Space Plasma Chamber has been hindered by the lack of a suitable plasma diagnostic instrument and understanding of its hot-filament plasma source. This thesis describes efforts made to remedy both problems. A wide-range Sweeping Langmuir Probe was developed with a ±35 V sweeping range to fully analyze ion and electron saturation regions in the entire IV curve. A method was derived to estimate the chamber source’s filament temperatures. The new Langmuir probe was integrated into a refurbished automated system designed in Python to measure plasma parameters for various chamber conditions, …

Solar Sailing Adaptive Control Around The Earth-Moon Lagrange Point L4 For Stellar Observations, Luis Mendoza Zambrano

Doctoral Dissertations and Master's Theses

To expand our knowledge about the influence of the Sun in the cislunar region, as well as our understanding of shocks due to Coronal Mass Ejections and large coronal magnetic reconnection, a solar sailing approach is proposed to separately capture lunar occultations and observe the solar corona from L₄ of the Earth-Moon system. Single and multiple shooting techniques are described along with a pseudo arc-length continuation method for preliminary orbit design. Periodic orbits in the vicinity of L₄ are obtained in the context of the Earth-Moon circular restricted three-body problem (CR3BP) and the Sun-Earth-Moon bi-circular restricted four-body problem …

Satellite Reorientation Using Reinforcement Learning Under Unknown Attitude Failure, Matthew Willoughby

Doctoral Dissertations and Master's Theses

This study presents a reinforcement learning (RL) approach for reestablishing communication with deep-space satellites under unknown attitude determination and control system (ADCS) failures. When traditional fault-tolerant control methods cannot restore signal, the proposed RL controller acts as a last-resort measure by autonomously reorienting the satellite’s antenna toward Earth while charging the battery via solar panels. A generic reward function, designed for the RL-based method, enables the controller to adapt to diverse failure scenarios, including severe actuator noise, misalignment, and complete actuator failure. Simulations are conducted in the Basilisk environment and trained with the tonic framework and demonstrate ranging capabilities of …

Soft Modular Robots: From Modular Tensegrity Structures To Bioinspired Sea Robots, Luyang Zhao

Dartmouth College Ph.D Dissertations

The rapid advancement of robotics necessitates systems capable of adapting to complex, unstructured environments. Soft robots, with their flexibility and compliance, excel in delicate interactions, making them ideal for medical applications and search-and-rescue missions. Modular robots, on the other hand, offer reconfigurability, enabling diverse task-specific adaptations in dynamic settings. Despite their individual advantages, the integration of soft and modular robotics remains underexplored. This proposal aims to develop soft modular robots that combine the adaptability of soft robotics with the versatility of modularity. These systems will be capable of autonomously transitioning between locomotion, manipulation, and infrastructure assembly across land, water, and …

Unified Evaluation Of Real-World Iot-Based Federated Learning, Yi Gu

Master's Theses

Federated learning (FL) is a novel paradigm that enables the training of a global machine learning (ML) model across distributed devices by exchanging model parameters instead of raw data in the training process. Internet of Things (IoT) devices typically operate with limited resources, have weaker security protections, and are more vulnerable to potential thermal stress (TS). Current evaluations of FL are mostly conducted through simulations of multiple clients on a single device. However, there remains a gap in understanding how FL performs under TS in real-world, low-power IoT environments. Conformal prediction (CP) is an effective method for quantifying uncertainty in …

Estimating Pedestrian Crossing Times At Scramble Crossings Via Machine Learning And Agent-Based Modeling, Sho Takami

Honors Capstones

Scramble crosswalks differ from conventional crosswalks in their ability for pedestrians to cross diagonally. This research compares the average crossing times and investigates the walking behaviors that pedestrians adopt to produce the speediest times in the two crosswalk configurations. Identification of the most efficient set of walking behaviors is done through an agent-based model, whereas producing polynomials relating crossing times to the most prominent walking behaviors is done through regression algorithms in machine learning. With the combination of these two approaches, it is revealed that pedestrians must adopt a relaxed walking style to make each crosswalk configuration efficient. Additionally, between …

First-Principles Studies Of Electrical Polarization Effects In Ferroelectrics, Antiferroelectrics And Defects, Louis Alaerts

Dartmouth College Ph.D Dissertations

Over the last few decades, density functional theory (DFT) has emerged as a formidable tool in the field of computational material science. Not only has it become a complementary method approach to experiments by rationalizing the many complex properties of materials but its formidable predictive power can also be used to identify the most promising candidates for specific applications. Point defects in semiconductors have become an important platform for the development of quantum networks due to their ability to act as spin-photon interfaces. Spectral diffusion, the broadening of the optical emission line, can significantly impact the performance of these defect-based …

Data-Driven Dynamic Decision-Making Using Discrete Optimization And Supervised Machine Learning, Navid Rashedi

Dartmouth College Ph.D Dissertations

In recent years, the operations research community has developed data-driven optimization techniques to solve complex combinatorial problems with the aid of machine learning. This thesis contributes to these efforts by combining machine learning with optimization to expedite online decision-making, with applications in transportation and healthcare.

In the domain of airline operations recovery, the focus is on the aircraft recovery process—repairing disrupted schedules by minimizing overall disruption costs. Traditional exact methods are too time-consuming, while heuristic approaches often yield poor solution quality and lack generalizability across varying formulations. To address these challenges, this research employs supervised machine learning to identify near-optimal …

Spatial Distribution Of The Bankfull Discharge Recurrence Interval Across Tennessee, Usa, Brayden P. Flanagan

Honors Theses

Stream restoration and water resources engineers use a wide variety of hydrological tools and refer to multiple databases to determine accurate watershed and stream characteristics required for site assessment and restoration projects. Regional curves provide significant watershed and stream data that stream restoration engineers use in various restoration projects. However, developing these curves is time-consuming, costly, and complex, as data collection and validation require extensive field studies at multiple sites within the restoration areas. This study evaluates whether pertinent information on regional curves and streamflow frequency could be combined to provide practical guidance on determining design peak flow discharges for …

Pressure Switch Tester, Michael Starasinich, Andrew Dobson, Jordan Huschen, Mitchell Smith, Melvin Brown Iii

Honors Capstones

Abstract—- The Pressure Switch Test Stand is a comprehensive and automated testing solution designed to streamline the actuation and validation of simultaneously. At the core of the system is a PLC-controlled architecture that enables precise control and simulation of pressure conditions, replicating real-world scenarios to ensure accurate and reliable switch performance.

This test stand integrates robust mechanical fixtures, a reliable pneumatic control system, custom-designed electrical circuits, and a modular software interface, working in unison to deliver consistent and high-fidelity testing outcomes. Each pressure switch undergoes a sequence of pressure ramps and holds, with the system continuously monitoring switch states, activation …

Dna Storage Of Images: From Pixels To Molecules, Cihan Ruan

Engineering Ph.D. Theses

DNA storage is rapidly emerging as a transformative solution for long-term, ultra-dense, and energy-efficient archival systems. This dissertation builds upon a deep understanding of image compression principles to design encoding frameworks that are uniquely attuned to the biochemical constraints of DNA storage. By fusing insights from traditional coding with molecular-level design, we develop a series of technically advanced solutions tailored for this emerging medium.

Our first contribution introduces Dynamic DNA-Fountain, a constrained codec that maps H.266 /VVC-compressed bitstreams to quaternary DNA sequences, optimizing for both information density and biochemical synthesis constraints. Building upon this foundation, we shift focus toward robustness—leveraging …

Intercellular Stress Generation During 1d Collective Migration Of Cancer Cells, Logan Waddle

Physics Undergraduate Honors Theses

Physical forces drive many cellular processes such as migration and proliferation. A metastatic tumor will have invasive strands/chains that extend from the main tumor. These chains of cells collectively migrate away from the main tumor to establish new colonies elsewhere in the body. However, how physical forces drive this collective invasion and the required energy for this process is not well understood. Invasion of a metastatic tumor to surrounding tissues leads to a majority of cancer-associated death and is often a collective effort among cells, it is therefore important to fully understand the process behind collective cancer invasion.

The goal …

Collecting Human Subject Data For Modeling Maximum Potential Power At Specific Cadence And Fatigue Levels, Alexander John Minnich

Honors College Theses

The overarching goal of this research project was to investigate the relationship between a participant's maximum power (Watts) at a given cadence (RPM) on a specific fatigue level. Before conducting any experiments, we hypothesized that maximum power and cadence would decay linearly with fatigue. To do this, six days of testing for each of 4 human subjects were split across two phases. The first 4 days were devoted to Phase one, which focuses on determining the physical abilities of each unique participant and finding metabolic constants such as Critical Power and Anaerobic Work Capacity. Phase two then tests maximal power …

Effect Of Beam Bracing On The Seismic Performance Of Laterally Skewed Reduced Beam Section Moment Connections With Composite Concrete Slabs, Pratik Ghimire

Graduate Theses and Dissertations

Existing experimental reduced beam section (RBS) moment frame investigations, particularly those used for prequalification in AISC-358, consider orthogonally oriented beam-to-column connections. While the design commentary provided in AISC-358 references recent skewed SMF numerical studies and potential performance effects when a lateral beam skew is introduced, limited experimental studies have been performed to verify the numerical findings. This study presents an experimental investigation into the cyclic behavior of RBS special moment frames that have lateral skew at the beam-to-column connection and composite concrete slabs. In this study, a skewed composite double-sided RBS connection is tested, having beam bracing outside the RBS …

Novel Atomic Layer Deposition Processes Of Silver For Battery Applications, Darlington Ehijie Imhanzuaria

Graduate Theses and Dissertations

This thesis presents a novel approach to enhance the performance and stability of anode-free lithium-ion batteries (AFLBs) by employing atomic layer deposition (ALD) to coat copper (Cu) current collectors with a silver-aluminum oxide (AgAlO_x) layer. Leveraging the unique capabilities of ALD for precise and conformal deposition, the AgAlO_x coating was achieved using triethyl phosphine-(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato)-silver(I) (Ag(fod)(PEt₃)), trimethylaluminum (TMA), and de-ionized water (H₂O) as precursors. This innovative coating method significantly enhanced the cycling stability and Coulombic efficiency (CE) of both Li||Cu and Cu||NMC811 cells, as evidenced by improved electrochemical performance metrics. The AgAlO_x layer …

Sample Archival System For Quantum Device Manufacturing: Design, Construction, And Integration, Corbin Russ

Graduate Theses and Dissertations

In the manufacturing of quantum devices using 2-dimentional (2D) materials, current processes rely on manual operations of production. MonArk Quantum Foundry is developing a facility to semi-automatically, and ultimately automatically, produce 2D materials. One crucial step in the experimentation process is archiving these materials and completed chips for future access. The sample archival system robot was produced to fulfill this need. The system is a 4 Degree-of-freedom (DOF) cartesian storage system that stores custom aluminum chip trays of sixty samples, having a total storage capacity of 14,400 samples. The sample archive system meets key goals from: it integrates with the …

Thermal Design And Control Of A Pcb-Based Solid-State Gas Generator (Ssgg) Heater For Space Applications, Chandler Dye

Graduate Theses and Dissertations

This thesis presents the development and experimental validation of a compact, solid-state gas generator (SSGG) heater integrated into a printed circuit board (PCB) for use in satellite deorbiting systems. Designed for CubeSat-class spacecraft, the system produces gas via the thermal decomposition of sodium azide (NaN₃). The project emphasizes minimal mass, low power consumption, and mechanical simplicity – key constraints for modern space missions. The heater system relies on Joule heating through patterned copper coils embedded within the PCB structure. NaN₃ is deposited into wells drilled into the board surface, where localized heating initiates its decomposition near 300°C. A range of …

Using Scaffolding, Gamification, And Self Awareness To Create Responsive Ux/Ui In Cad Software To Nurture Metacognition In Novice Users, Obed Ibrahim Gonzalez

Graduate Theses and Dissertations

Computer-aided Design (CAD) software represents a significant shift from manual and analog design processes to digital workflows, offering substantial utility, accuracy, and productivity benefits. However, CAD software often presents a steep learning curve, particularly for novice users who are new to the software or possess only basic knowledge. Traditional CAD curricula have predominantly focused on technical problem-solving—teaching tools and systems—while often neglecting strategic knowledge that encompasses reflection, planning, and refining, which are essential components of metacognition. Metacognition is crucial for transforming novices into experts who use fewer and more complex commands, employ sophisticated planning, and achieve their goals more efficiently. …

Development And Investigation Of A Novel Near-Wall Methodology For Large-Eddy Simulation Based On Dynamic Hybrid Rans-Les, Michael Tullis

Graduate Theses and Dissertations

The use of computational fluid dynamics (CFD) to test engineering designs with reduced cost and time compared to physical testing has become increasingly common in a range of industries and research fields. While numerical methods exist that can accurately solve the equations that govern the flow of fluids, these methods are computationally expensive for practical engineering problems due to the large amount of computational power needed to resolve the fluid flow over the entire range of length and time scales. Several different approaches have been introduced to address this computational cost issue, namely Reynolds-averaged Navier-Stokes (RANS) modeling and scale resolving …

Mechanical Properties And Microstructural Characteristics Of Hydrated Bcsa Cement At Extreme Temperatures, Behzad Farivar

Graduate Theses and Dissertations

Belitic Calcium Sulfoaluminate (BCSA) cement is an alternative binder known for its rapid setting and high early strength, making it ideal for applications such as fast-track construction and repair. This study presents a comprehensive investigation into the behavior of BCSA cement under a wide range of curing temperatures, with emphasis on early-age strength development, admixture effects, and the use of the maturity method for strength prediction.

The research evaluates BCSA cement performance in both hot and cold environments, ranging from approximately -28.9 °C (-20°F) to 49 °C (120°F). In warm climates, citric acid was used as a set retarder to …

Generative Ai In Cs Education: Navigating The Intersection Of Student Usage And Faculty Vision, Matthew Scott Mcclenahan

Graduate Theses - Engineering Management

Generative AI tools are rapidly transforming both educational and professional landscapes, creating an imperative for computing education to adapt. This mixed-methods study investigates how Computer Science and Software Engineering students utilize these tools and how faculty perceive their impact within a small private STEM institution. Through surveys of 40 CS/SE students and 29 faculty members, complemented by in-depth interviews with 10 faculty, this dual perspective enables direct comparison between student practices and faculty perceptions, helping to identify areas where educational policies and practices may need adjustment.

Analysis identified six distinct categories of GenAI usage: Learning Enhancement (29.2%), Productivity and Efficiency …

Mentorship As Experienced By Black Woman In Stem At Predominantly White Institutions, Chelsei Lasha Arnold

Honors Theses

Black female college students have experienced a marginalized history in STEM higher education. Although students associated with this identity are enrolling and earning college degrees at historic rates, there is a gap in the resources available, especially at predominantly white institutions (PWIs), for these students once they reach collegiate level. The goal of this study is to examine the role of mentorship in the lived experiences of Black women STEM students at PWIs. I used interpretive phenomenological analysis on transcribed interviews to examine psychological patterns, and then I carefully analyzed the phenomenon of being mentored. Through the analysis, I sought …

Analysis Of The Mechanical, Microstructural, And Biocompatibility Properties Of Novel Magnesium-Based Hybrid Nanocomposite Materials For Orthopedic Applications, Thomas H. Mcgehee

Biomedical Engineering Undergraduate Honors Theses

Bone fractures and complete joint replacements are becoming more common, primarily because of accidents and age-related issues. Conventional solutions to treat these orthopedic injuries involve inert metal alloys to correct bone fractures until the healing process is complete, where a secondary revision surgery is then required to remove the implant. Issues regularly associated with these solutions include stress shielding, bone resorption, infection, inflammation, and implant loosening. Magnesium (Mg)-based nanocomposites offer promising potential as an alternative to commonly used metal alloys because of their favorable mechanical properties and biocompatibility. A particularly advantageous property of Mg is its natural biodegradation in vivo, …

Fff Process Parameter Identification With Machine Learning Models, Owen Davis Smith

Honors Theses

Additive manufacturing (AM) has seen increasing popularity in recent times, owing to its efficiency and high speeds, particularly with processes such as Fused Filament Fabrication (FFF). Input process parameters have large impacts on the final part. Incomplete process parameters, which can occur for a variety of reasons, make tasks such as replicating AM studies difficult. A machine learning model can be trained on in-situ layer-wise images collected during a print to combat this issue, predicting process parameters with sufficient data. In this study, two parameters were tested: infill pattern orientation and extrusion width. Twelve parts were produced per parameter and …

Understanding Initial Capacity Loss In Substituted Layered Oxide Cathodes For Lithium-Ion Batteries, Gy Wyco

Graduate Dissertations and Theses

Layered oxide LiCoO₂ (LCO) pioneered the commercialization of lithium-ion batteries (LIBs) in 1991, yet the growing demand for higher energy density has driven the development of substituted layered oxides, including LiNiᵧMn𝓏Co₁₋ᵧ₋𝓏O₂ (NMC) and LiNiᵧCo₁₋ᵧ₋𝓏Al𝓏O₂ (NCA). Despite the increased energy density, achieving full lithium reversibility during the first charge-discharge cycle remains a critical challenge: approximately 0.08–0.11 Li is “irreversibly” lost after delithiation, resulting in a substantial capacity loss of 10–15%. This loss is conventionally attributed to bulk lithium transport limitations arising from three interrelated factors: (1) contraction of the c-axis lattice during lithiation, (2) reduced rate of tetrahedral site hopping (TSH) …

Gpu-Based Visual Effects System, Matthew Jaffe

Programming Theses and Dissertations

The objective of my thesis is to create a robust and efficient VFX system that can be used to edit and add particle effects to games. This system utilizes a compute shading pipeline to simulate millions of particles in real time. The behavior of particles is widely customizable through many different properties which can be manipulated changed over the lifetime of particles and introduce procedural randomness. There are many ways to customize the motion of the particles with various forces and collision. Additionally, particles can be rendered as billboarded quads, full meshes or partial meshes with different settings to further …