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Full-Text Articles in Engineering

Evaluating The Potential To Increase Oil Production From Legacy Fields In Montana, Noel Dapilee Aug 2025

Evaluating The Potential To Increase Oil Production From Legacy Fields In Montana, Noel Dapilee

Graduate Theses & Non-Theses

This research assesses the potential for Enhanced Oil Recovery (EOR) techniques to boost oil production in Montana. Eight major oil basins in Montana, comprising over 350 oil fields, were analyzed. Using a volumetric analytical method, the original oil in place (OOIP) was estimated for 42 fields where sufficient data were available for the calculation. By comparing the cumulative oil production with the OOIP, fields with significant remaining reserves were identified. Data for this project was obtained from the Montana Geological Society (MGS) and the Montana Board of Oil and Gas (MBOG), which provided comprehensive information on reservoir properties, fluid characteristics, …


Modeling Copper Biogeochemistry In Continental Environments: 0 – 93 °C, Paul Goldsborough Helfrich Aug 2025

Modeling Copper Biogeochemistry In Continental Environments: 0 – 93 °C, Paul Goldsborough Helfrich

Graduate Theses & Non-Theses

Microbiomes are intertwined with copper chemistry through both toxin and trace nutrient interactions. We produced and examined nineteen metagenomes from a creek recovering from historic copper mining to investigate how anthropogenic contamination shapes microbial community structure and functional potential. We then incorporated the metagenomic profiles and concurrently collected geochemical context into multivariate models to examine correlations between habitat geochemistry and microbial ecology. Residual copper and wastewater inputs alter stream habitability across seasonal gradients. We complimented initial analyses with new insights from high temperature environments. Combined dissolved inorganic carbon (DIC), temperature, pH, and silica stress constrain photosynthesis in hydrothermal features. Geochemical …


Design, Modeling, Control, And Analysis Of A Modular Two-Wheeled Self-Balancing Robotic System, Mishek Jair Musa Aug 2025

Design, Modeling, Control, And Analysis Of A Modular Two-Wheeled Self-Balancing Robotic System, Mishek Jair Musa

Graduate Theses and Dissertations

Two-wheeled self-balancing robots have garnered substantial attention within the realms of research and innovation in academia and industrial settings. In particular, advances in control algorithms, machine learning, reinforcement learning, and sensor technologies have played a pivotal role in their development. Although primarily recognized for their utility in personal transportation in the commercial sector, these robots possess potential applications across various domains, including search and rescue, healthcare, material handling, logistics, etc., due to their active stabilization and exceptional maneuvering capabilities. A particular area of interest lies in the creation of modular self-balancing robots designed for seamless reconfiguration and enhanced human interaction. …


Integration And Testing Of A Quadruped Robot With Ros2, Jeremy S. West Aug 2025

Integration And Testing Of A Quadruped Robot With Ros2, Jeremy S. West

Master's Theses

The Cal Poly Legged Robotics Group has been developing research and teaching platforms for agile legged robotics since 2020. These platforms are expected to provide students with opportunities to develop complete legged-robot systems from low-level control to advanced robotics tasks such as motion planning and decision making. However, the current prototyped quadruped robot lacked the software and sensing capabilities for high-level quadrupedal gaits and advanced robotic research.

To address these challenges, this project developed Switch, a robotic platform that builds upon the previous BRUCE platform with significant hardware and software upgrades. Switch features a modular design that allows individual software …


Development Of A Control System For An 8-Dof Quadrupedal Robotic Research Platform, Jack Butler Aug 2025

Development Of A Control System For An 8-Dof Quadrupedal Robotic Research Platform, Jack Butler

Master's Theses

Quadrupedal robots offer a versatile locomotion option that can extend the operating space of a robot into uneven terrains. However, controlling these systems presents significant challenges due to nonlinearities introduced by various factors.

In this thesis, model-predictive control (MPC) is applied to an 8-DOF legged robot developed by Cal Poly’s Legged Robotics group. The MPC framework employs a lumped rigid-body model that treats the robot as a single rigid body with forces applied directly at the foot contact points. The controller is developed within the ROS2 environment, with integration of state estimation and gait-pattern generation, to provide maximum modularity and …


Evaluating (Bio)Degradation Of Carbon Tetrachloride In Fe(Iii)-Reducing Environments, Adam Rogers Aug 2025

Evaluating (Bio)Degradation Of Carbon Tetrachloride In Fe(Iii)-Reducing Environments, Adam Rogers

All Theses

Understanding degradation of carbon tetrachloride in-situ is vital for many remediation projects across the world, yet conclusive evidence of its feasibility is lacking in previous studies.

The main objective of this research is to assess the potential for carbon tetrachloride attenuation by biological, abiotic, and combined processes in a Fe(III)-reducing aquifer. In doing so, it assesses the effect of pH and stoichiometric ratio on abiotic degradation of carbon tetrachloride using various reducing agents, evaluates iron-mediated versus direct biotic degradation of carbon tetrachloride using pure cultures under resting and growth conditions, and characterizes the effects of culture strain, electron acceptors and …


Owl Solar-Powered Link: Duck Radio Mesh For Autonomous Monitoring, Jaden Tran, Shane Williams Aug 2025

Owl Solar-Powered Link: Duck Radio Mesh For Autonomous Monitoring, Jaden Tran, Shane Williams

Electrical Engineering

The Solar Duck Sensor Node transforms a standard DuckLink into a fully self-sustaining environmental monitor. A compact solar panel / power bank module plugs into the power ports of both the DuckLink and the Raspberry Pi Zero 2 W, keeping them charged through day-night cycles. The Pi Zero 2 W will perform local processing of sensor data. Sensor output will come from the Raspberry Pi AI Camera and its object detection capabilities. This output will be distilled into metadata and advertised over BLE. The DuckLink captures these packets, encapsulates them into LoRa payloads, and forwards them across the ClusterDuck mesh …


Simulation Of Photochemical Effects On Air Quality, Grace Li Aug 2025

Simulation Of Photochemical Effects On Air Quality, Grace Li

Chemical Engineering Undergraduate Honors Theses

Nitrogen dioxide (NO2) and ozone (O3) are both EPA criteria air pollutants in the troposphere, largely generated by combustion and therefore present in significant concentrations in urban areas. Sunlight facilitates chemical reactions between pollutants and ambient air. Aerosols modulate the amount of available energy required to drive such photochemical reactions, ultimately impacting air quality. Simulating photolysis rates with FastJX software is a resource-efficient strategy to study how these aerosols can affect air quality.


Analysis On Plasma Propulsion Thruster Material Reconfiguration For Thrust Stabilization, Chinedumu Chidiebere Okafo Aug 2025

Analysis On Plasma Propulsion Thruster Material Reconfiguration For Thrust Stabilization, Chinedumu Chidiebere Okafo

Mechanical & Aerospace Engineering Theses & Dissertations

Rocket propulsion has been a primary focus for scientific and technical advancement supporting space exploration. For long-duration, low-thrust space missions, propulsion systems designed with plasma energy as the primary source for generating thrust are of high interest. Plasma energy, like electric propulsion, involves the excited state of ionized atoms, where the ionized particles are separated and then act as a propellant to push a spacecraft in the intended direction for flight. Although more energy efficient compared to traditional rocket systems, plasma propulsion has the deficiency of consistent erosion of the metallic containment substrate, as plasma is being generated and released …


Multimedia Forensics: Identification And Verification Of Source Camera, Vehicle Speed Estimation, And Deepfakes Detection, Jiajun Jiang Aug 2025

Multimedia Forensics: Identification And Verification Of Source Camera, Vehicle Speed Estimation, And Deepfakes Detection, Jiajun Jiang

Electrical & Computer Engineering Theses & Dissertations

This dissertation advances multimedia forensics by addressing three critical research areas that enhance the authenticity verification and analysis of digital media. Multimedia forensics, which encompasses techniques for examining images, videos, audio, and text, faces increasing challenges due to sophisticated editing tools and massive data volumes. In the first study, a fast source camera identification and verification method based on PRNU analysis is proposed for video forensic investigations. By integrating camera rolling and I-frame analysis, this approach achieves a processing speed improvement of at least 15 times over conventional frame-by-frame methods while reducing false positives. The second study focuses on vehicular …


Effects Of Variation In Altitude And Temperature On The Restraining Force And Internal Gauge Pressure Of Constrained Dunnage Airbags, Charles R. Weaver Aug 2025

Effects Of Variation In Altitude And Temperature On The Restraining Force And Internal Gauge Pressure Of Constrained Dunnage Airbags, Charles R. Weaver

All Theses

Dunnage airbags are an increasingly popular choice for securing cargo. During transit, changes in ambient temperature and pressure can cause airbags to expand generating damaging horizontal compressive forces in the trailer or container. Previous studies have developed numerical models for the behavior of Kraft paper and woven polypropylene fabric dunnage airbags under standard conditions but do not account for the behavior of airbags under varied altitudes and temperatures. This study provides empirical data on the internal gauge pressure and restraining force dynamics of 4-ply Kraft, woven polypropylene, and polyvinyl chloride airbags under simulated altitude and temperature conditions. Tensile testing characterizes …


Advancing Multi-Physics Modeling For Microwave Heating: Application In Micro-Reactor Design And Optimization, Raghav Adhikari Aug 2025

Advancing Multi-Physics Modeling For Microwave Heating: Application In Micro-Reactor Design And Optimization, Raghav Adhikari

All Theses

Microreactors are a type of small-scale chemical reactors for achieving reduced volume, improved product selectivity and higher reaction rate. It allows precise temperature control, which is crucial for sensitive chemical processes. Microreactors can be employed as key components of conducting small-scale reactions with improved reactor configuration and process efficiency. It is important to identify a localized and precise heating mechanism to trigger and control the corresponding chemical reactions.

In fact, microwave heating has gathered significant attention in recent years due to its ability to deliver efficient, rapid, and localized heating, which can accelerate reaction rates and enhances the reaction selectivity. …


Optimizing Park Locations While Considering Resident Behavior, Lu Liu Aug 2025

Optimizing Park Locations While Considering Resident Behavior, Lu Liu

All Theses

Urban parks and green-spaces significantly enhance community well-being by improving physical health, mental wellness, and environmental quality. Given these extensive benefits, ensuring fair and widespread access to urban parks represents a critical priority in urban planning. Despite the advantages of parks, optimizing their location poses unique and complex challenges distinct from traditional facility location problems, such as those involving emergency services or schools. The core distinction arises from the decentralized nature of residents’ park selection behaviors. Unlike centralized allocations typically managed by public administrators, park usage decisions are driven by individual preferences and behaviors. This decentralized decision-making introduces two additional …


Evaluating The Impact Of Activated Carbon On The Biodegradation Of Btex Compounds, Megan Barkley Aug 2025

Evaluating The Impact Of Activated Carbon On The Biodegradation Of Btex Compounds, Megan Barkley

All Theses

BTEX compounds—benzene, toluene, ethylbenzene and xylenes—are toxic, volatile, aromatic hydrocarbons. They are primarily found in petroleum products and can easily enter the environment. Typical remediation techniques include sorption to activated carbon, pump and treat, and bioremediation. Research suggests that combining sorption to activated carbon and bioremediation may enhance BTEX removal. This study evaluates the impact of granular activated carbon (GAC) on the biodegradation of ethylbenzene and toluene, using an enrichment culture of aerobic bacteria.

The main objectives of this study are to grow and maintain a culture that degrades BTEX compounds, evaluate the effect of activated carbon on the biodegradation …


Development Of A Homogenized Material Model For Carbon Fiber–Aluminum Transition Joints Using Fea And Optimization, Nicholas M. Couch Aug 2025

Development Of A Homogenized Material Model For Carbon Fiber–Aluminum Transition Joints Using Fea And Optimization, Nicholas M. Couch

All Theses

The integration of metals and composites in automotive structures improves manufacturability and overall structural performance. The proposed Ultrasonic Additive Manufacturing (UAM) joint provides a promising solution for joining aluminum and carbon fiber; however, modeling its behavior across an entire vehicle can be computationally expensive. To address this challenge, a homogenized material card is developed to efficiently capture the joint’s mechanical response while maintaining computational efficiency. A novel characterization method is implemented, employing implicit simulations and optimization techniques to determine the effective material properties of the UAM transition joint. This approach enables rapid iteration of material parameters, facilitating the efficient evaluation …


Computational Study Of Nonlinear Electrokinetic Phenomena In Shear-Thinning Fluids, Wai Yuen Leung Aug 2025

Computational Study Of Nonlinear Electrokinetic Phenomena In Shear-Thinning Fluids, Wai Yuen Leung

All Theses

Electrokinetic phenomena have been widely used for fluid pumping and particle manipulation in micro/nanofluidic systems. They refer to the motion of fluids or particles in response to an electric field because of the spontaneous formation of an electric double layer at the fluid-solid interface. Understanding electrokinetic phenomena in micro/nanochannels is critical for a wide range of applications across various engineering fields, such as disease diagnostics, contaminant treatment and cell analysis. To date, numerous studies have been reported on electrokinetic phenomena in Newtonian fluids, where the classical Helmholtz-Smoluchowski theory indicates a linear relationship between fluid electroosmosis/particle electrophoresis and electric field. However, …


Life Cycle Assessment Of The Cultivation Of Lettuce In A Hydroponic System Using The Nutrient Film Technique, Raquel Jordan Aug 2025

Life Cycle Assessment Of The Cultivation Of Lettuce In A Hydroponic System Using The Nutrient Film Technique, Raquel Jordan

All Theses

Hydroponic systems are an emerging method of soilless crop cultivation typically done inside a greenhouse where nutrients are delivered dissolved in water rather than being supplied from the soil. Potential benefits of hydroponic systems include reduced irrigation requirements, higher crop yield per area, and the ability to grow crops year-round in nontraditional areas such as urban settings, cold climates, and sites with contaminated soil. However, hydroponic systems tend to have high energy requirements for lighting and climate control, which can yield significant environmental impacts. To explore the environmental impacts of cultivating lettuce in a nutrient film technique (NFT) hydroponic system, …


The Development And Application Of A Method To Simulate Commotio Cordis Inducing Impacts For The Evaluation Of Football Chest Protective Equipment, Bianca J. Henline Aug 2025

The Development And Application Of A Method To Simulate Commotio Cordis Inducing Impacts For The Evaluation Of Football Chest Protective Equipment, Bianca J. Henline

All Theses

As one of the most widely played and watched contact sports in the United States, football presents a significant risk of blunt chest trauma. Thus, effective chest protection is essential to prevent rare but fatal injuries like commotio cordis. Despite this, current test methods for certifying chest protective equipment fail to account for injury metrics relevant to commotio cordis events. Recent literature identifies rib deformation and viscous criterion as critical predictors of commotio cordis, yet these metrics are not adequately addressed in the existing testing standard. Furthermore, this standard exclusively assesses chest gear specific to baseball and lacrosse through projectile …


Machine Learning Based Medical Ultrasound Image Classification And Grad-Cam Interpretation, Victoria C. Hemphill Aug 2025

Machine Learning Based Medical Ultrasound Image Classification And Grad-Cam Interpretation, Victoria C. Hemphill

All Theses

This work takes a step in creating a diagnostic tool for the classification decision process of Achilles tendinopathy using ultrasound images. An attention-based multiple instance learning model is developed to classify the images. Typically, doctors capture multiple ultrasound images of the Achilles tendon during a study to determine a complete diagnosis. Multiple instance models adopt this behavior by providing a single label for a set of instances (images). The images are grouped into ”bags” at the study level and passed into the model. The MIL model then uses its attention property to assign an importance score to each image to …


Visor-Zt: A Visibility, Simulation, And Operational Resilience Framework For Zero Trust Security In Ros 2, Noah Tinker Aug 2025

Visor-Zt: A Visibility, Simulation, And Operational Resilience Framework For Zero Trust Security In Ros 2, Noah Tinker

All Theses

Robotic systems are becoming more and more prevalent in modern society, with Robot Operating System 2 (ROS 2) being the dominant operating system for these implementations. Its popularity can be attributed to its design, which is purpose-built for distributed systems and asynchronous communications. However, ROS 2 security is static and therefore less capable of responding to contemporary threats and network behavior. This becomes a greater issue when considering its applications in the military and defense sectors, where security is of the highest importance. In recent years, the U.S. Department of Defense (DoD) has implemented zero trust (ZT) security based on …


Effectiveness Of Electrosynthesized Hydrogen Peroxide In Urease Inactivation For Stabilization Of Source-Separated Urine To Recover Urea, Brooke E. Covert Aug 2025

Effectiveness Of Electrosynthesized Hydrogen Peroxide In Urease Inactivation For Stabilization Of Source-Separated Urine To Recover Urea, Brooke E. Covert

All Theses

The practice of separating urine at a building scale, rather than mixing with domestic wastewater to be treated at water resource recovery facilities, allows for concentrated urine to be directly treated with the aim of resource recovery. However, source separation and treatment present challenges during separation, storage, and transport. This study evaluated the use of hydrogen peroxide-producing electrochemical cells, which represent a technology that uses electricity as an input, to stabilize urine through cathodically produced peroxide to enable downstream water and nutrient recovery. The electrochemical cells have been previously shown to stabilize urine with electrochemically produced peroxide as an effective …


A Generalizable And Privacy-Preserving Framework For Anomaly Detection In Heterogeneous Iot Environments, Mahshid Rezakhani Aug 2025

A Generalizable And Privacy-Preserving Framework For Anomaly Detection In Heterogeneous Iot Environments, Mahshid Rezakhani

All Theses

With the rapid growth of Internet of Things (IoT) devices across various sectors, detecting anomalies in such systems has become increasingly challenging. IoT environments produce diverse and evolving data streams, often lacking labeled examples, which limits the effectiveness of traditional machine learning models. These models typically require frequent retraining and struggle to adapt to new deployment conditions. This thesis proposes a flexible, privacy-aware framework for anomaly detection in multivariate time series data generated by heterogeneous IoT systems. The approach integrates a long short-term memory variational autoencoder (LSTM-VAE) with contrastive learning and adversarial adaptation, enabling the model to generalize across domains, …


Polyphenols For The Mitigation Of Vascular Calcification; In Vitro And In Vivo Studies, Abdullah Altuhami Aug 2025

Polyphenols For The Mitigation Of Vascular Calcification; In Vitro And In Vivo Studies, Abdullah Altuhami

All Theses

Globally, cardiovascular diseases, in most cases associated with calcification, are the main cause of death. However, currently, the only effective cure is to undergo surgery to augment or receive a healthy donor heart, which could be very difficult due to the long waiting list and the associated risks. The possibility of body rejection of the foreign organs is attributed to immunoreaction or the risk of infection, since the donor must be on immunosuppressant drugs that lower the body's immunity and facilitate the body's acceptance of the new organ as one of its own. Taking that into consideration, using tissue-engineered vascular …


Effect Of Cigarette Smoke Extract And Nutrient Deficiency On Energy Metabolism And Biosynthesis: An In Vitro Intervertebral Disc Explant Culture Study, Avery E. Madden Aug 2025

Effect Of Cigarette Smoke Extract And Nutrient Deficiency On Energy Metabolism And Biosynthesis: An In Vitro Intervertebral Disc Explant Culture Study, Avery E. Madden

All Theses

Low back pain consistently ranks among the leading causes of disability worldwide, with degenerative changes in spinal intervertebral discs (IVDs) recognized as a key contributor. Degeneration arises from the disruption of mechanical and biological cues within the disc’s cartilaginous tissue, often exacerbated by aging or injury. In recent decades, cigarette smoking has also been identified as a significant risk factor, as IVD degeneration is more prevalent among individuals with a history of smoking. Smoke inhalation is thought to promote degeneration both directly, by exposing cells to water-soluble toxic chemicals in smoke; and indirectly, through nutrient deficiency resulting from vasoconstriction and …


Mission-To-Designs: Automating Uav Conceptual Design Generation, Nana A. Adjei Aug 2025

Mission-To-Designs: Automating Uav Conceptual Design Generation, Nana A. Adjei

All Theses

The conceptual design stage of Unmanned Aerial Vehicles (UAVs) is an exploratory phase where designers are tasked with developing and evaluating a wide range of viable design concepts, considering different geometries and configurations based on mission requirements. The goal is to identify the most suitable design after the exploration for further development and progression to the next phase. Several tools and frameworks have been developed to assist designers in this stage, each offering unique capabilities, but all with the common aim of aiding in the efficient development and evaluation of conceptual designs. This is important in the UAV design process …


Quantifying The Effect Of Initial Molecular Weight Distribution On The Degradation Of Linear Polyethylene At High Temperatures Using Dissipative Particle Dynamics, Cassandra L. Simpson Aug 2025

Quantifying The Effect Of Initial Molecular Weight Distribution On The Degradation Of Linear Polyethylene At High Temperatures Using Dissipative Particle Dynamics, Cassandra L. Simpson

All Theses

Polyolefins are the primary contributors to greenhouse gas emissions and supply chain energy requirements with respect to other commodity polymers. In order to explore more efficient methods for recycling and upcycling these plastics, it is important to consider the kinetics of polymer fragments during the degradation process to more accurately reflect experimental outcomes. The molecular weight distribution of synthetic polymers is an important factor to consider when synthesizing, processing, and manufacturing industrial plastics. The breadth of this distribution, or dispersity, is determined by the ratio of the weight average molecular weight to the number average molecular weight, and is correlated …


Technology-Enabled Foreign Object (Fo) Prevention, Christopher Lee Colaw Aug 2025

Technology-Enabled Foreign Object (Fo) Prevention, Christopher Lee Colaw

Open Access Theses & Dissertations

The aviation industry incurs $14 billion per year in cost due to Foreign Object (FO) damage and the prevention and resolution techniques associated with foreign object debris. While aircraft loss, material scrap and rework contribute to that cost impact, a traditional approach to aircraft design and manufacturing which is based on human performance is also a significant driver. Failure modes and effects analysis of human based aircraft manufacturing reveals that two of the largest risks are associated with unknown potential for FO creation and the inability to recall or objectively provide evidence of FO conformity for cases of inquiry, learning, …


Elucidation Of Nano-Mechanical Property Evolution Of 3d-Printed Zirconia, Diana Hazel Leyva Marquez Aug 2025

Elucidation Of Nano-Mechanical Property Evolution Of 3d-Printed Zirconia, Diana Hazel Leyva Marquez

Open Access Theses & Dissertations

This dissertation presents an in-depth look at the mechanical behavior, size changes, and process improvement of ceramic and polymer materials made with additive manufacturing (AM). The work consists of four separate but related studies, each tackling important challenges in fabrication, characterization, and predictive modeling. Chapter 1 examines the nano-mechanical property changes of 3D-printed zirconia made using digital light processing (DLP). By employing nanoindentation and scanning electron microscopy (SEM), the effects of print orientation and sintering on hardness, elastic modulus, and microstructure are revealed. The results indicate that 0°-oriented sintered samples have up to 140% higher hardness compared to preconditioned samples, …


Effective Transformer Networks For Undersampled Magnetic Resonance Image Reconstruction, Tahsin Rahman Aug 2025

Effective Transformer Networks For Undersampled Magnetic Resonance Image Reconstruction, Tahsin Rahman

Open Access Theses & Dissertations

The proliferation of data-driven tools for solving problems in every possible domain, coupled with rapid advances in computing technology, has led to an arms race of AI development and application research in industry and academia. One field of research that stands to gain immeasurably from this revolution is medical imaging. It is a critical part of modern diagnostics, and advancements in this area can directly benefit the average person by making healthcare more accessible, accurate, and affordable. Breakthroughs in mainstream image processing and computer vision have long fueled development in medical imaging, and it is now common to see cutting …


Low Energy Ion Irradiation Effects In Electronic Devices And Materials, David C. Mccall Aug 2025

Low Energy Ion Irradiation Effects In Electronic Devices And Materials, David C. Mccall

All Dissertations

The physics and engineering of ion-solid interactions are governed by the ion beam characteristics (flux, charge, energy) and target(s) in question. Here I present work on two projects related to the extraction of a high flux of low charge state Argon ions from a commercial plasma source and the irradiation of an engineered target, a transistor, with high charge state Argon ions.

An end-Hall ion source that produces a a high current plasma of ions and electrons in a rough vacuum environment is characterized. Using a Langmuir probe and multiple pressure measurements, the ion and electron content of the source …