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Full-Text Articles in Engineering

Nonlinear Dynamics And Control Of An Autonomously Operated Towed System, Brian Allan Carr Jan 2025

Nonlinear Dynamics And Control Of An Autonomously Operated Towed System, Brian Allan Carr

Wayne State University Theses

Emergency towing vessels are a vital component of maritime safety. This study works to improve on previous works in the area of automating the towing of disabled ships. In doing so control methods for transient three degree of freedom dynamics of a tug and tow system which is connected with a finite element cable are evaluated. A Heaviside unit step function is inserted to void both the elastic and viscous interaction between the massive elements whenever the distance between two neighboring masses appears to be below the corresponding undeformed distance. This follows the representation of the cable as a one-dimensional …


Investigating The Role Of Knee Damping In Reducing Joint Forces During Walking And Its Implications For Osteoarthritis Patients, Samantha Briggs Jan 2025

Investigating The Role Of Knee Damping In Reducing Joint Forces During Walking And Its Implications For Osteoarthritis Patients, Samantha Briggs

Wayne State University Theses

Arthritis is a leading cause of activity limitation and chronic pain worldwide. Particularly in cases of knee osteoarthritis, mobility impairments are largely due to pain at the arthritic joint. During normal gait, forces across the knee joint peak during the weight acceptance and early midstance phases. Hence, providing damping at the knee joint during this period of the gait cycle may be effective in decreasing the joint forces and pain experienced by osteoarthritis patients while walking. To examine the role of knee damping in reducing joint forces, an eddy current braking device was automated to provide targeted resistance at the …


The Design Of A Bioinspired Impact Mitigation System Towards The Prevention Of Brain Injuries, Bryce H. Reimer Jan 2025

The Design Of A Bioinspired Impact Mitigation System Towards The Prevention Of Brain Injuries, Bryce H. Reimer

Master’s Theses

Traumatic brain injuries (TBIs), including concussions and chronic traumatic encephalopathy (CTE), remain a major concern across contact sports, military operations, and transportation. Despite advancements in protective equipment, current strategies often fall short in preventing the mechanical conditions that contribute to long-term neurological damage. This thesis presents the design and validation of a bioinspired impact mitigation system modeled after bighorn sheep horn structures, which have evolved to endure high-energy collisions without apparent brain injury.

Using biomimetic principles, the research integrates experimental and computational methods to evaluate how horn-like geometries reduce impact-induced accelerations. A custom drop tower was built to test dynamic …


Evaluation Of Physical And Chemical Stability In Liposomes Composed Of Mixed Phospholipids, Sharareh Rezaei, Kenny Mineart Jan 2025

Evaluation Of Physical And Chemical Stability In Liposomes Composed Of Mixed Phospholipids, Sharareh Rezaei, Kenny Mineart

Master’s Theses

Liposomes, spherical vesicles composed of lipid bilayers, are widely used in drug delivery due to their biocompatibility, biodegradability, and ability to interact with biological membranes. Despite these advantages, liposomes remain moderately unstable systems, highly susceptible to environmental stressors such as pH fluctuations, ionic strength variations, temperature changes, and interactions with other components. Addressing both chemical and physical instability is essential for translating liposomal formulations from experimental formulation to viable pharmaceutical products.

This study investigates the physicochemical characteristics of a mixed-phospholipid system in which one lipid is saturated, and the other is unsaturated (DMPC and DOPC respectively). Liposomes are prepared using …


Development And Clinical Validation Of The Sensor-E Exoskeleton For Objective Hand Function Assessment In Stroke Rehabilitation, Madison Bates Jan 2025

Development And Clinical Validation Of The Sensor-E Exoskeleton For Objective Hand Function Assessment In Stroke Rehabilitation, Madison Bates

Theses and Dissertations--Biomedical Engineering

Hand function is often impaired following neurological trauma or in conditions such as stroke, limiting independence and the ability to perform activities of daily living (ADLs). Current clinical assessments rely heavily on subjective rating scales that lack the resolution to detect subtle changes in motor performance, which can limit access to rehabilitation. Recent advances in wearable technologies highlight the potential for hand-worn devices to provide objective, real-time measures of hand function. However, most systems focus solely on kinematics and rarely capture both movement and exerted force. Moreover, integration into rehabilitation frameworks and brain-computer interface (BCI) protocols remains limited. To address …


Image Processing And Machine Learning Using Lidar And 360 Camera In Underground Mines, Ana Fabiola Patricia Tejada Peralta Jan 2025

Image Processing And Machine Learning Using Lidar And 360 Camera In Underground Mines, Ana Fabiola Patricia Tejada Peralta

Theses and Dissertations--Mining Engineering

Underground mining environments present several safety challenges due to low visibility, poor lighting, and the absence of GPS coverage. These factors hinder situational awareness and delay hazard detection, particularly during post-disaster conditions. This research introduces an integrated framework that combines image processing and machine learning techniques applied to 360-degree camera and LiDAR data to enable automated object detection and remote monitoring in underground mines.

The study was divided into two main stages: 2D object detection and 3D object detection. The 2D component employed images captured with a Ricoh Theta Z1 360° camera and utilized YOLO-based deep learning models for object …


Performance Evaluation Of Managed Switch Configurations For Secure And Efficient Plc-Based Industrial Automation Networks, Ahmed Salama Jan 2025

Performance Evaluation Of Managed Switch Configurations For Secure And Efficient Plc-Based Industrial Automation Networks, Ahmed Salama

All Graduate Theses, Dissertations, and Other Capstone Projects

This thesis explores how managed switches can improve network performance and security in PLC-based industrial systems. Using simulations in GNS3 and Cisco Packet Tracer, and packet analysis via Wireshark, the study compares unmanaged and managed switch configurations. Redundancy protocols, particularly STP and RSTP, are evaluated under failure scenarios. Results show that RSTP offers faster recovery times, making it more suitable for time-sensitive environments. Additionally, managed switch features like VLANs, port security, and MAC filtering significantly reduce vulnerabilities and improve network segmentation. The findings highlight the importance of incorporating both cybersecurity and redundancy in industrial network design as systems move toward …


‘Waves Of Imagination’ Unconditional Spectogram Diffusion Using Diffusion Architecture., Rahul Vanukuri Jan 2025

‘Waves Of Imagination’ Unconditional Spectogram Diffusion Using Diffusion Architecture., Rahul Vanukuri

Computer Science and Engineering Theses - Archive

The swift evolution of wireless communication technologies,particularly in the field of rf signals or in CBRS bands,demands increasingly sophisticated signal processing techniques to ensure efficient transmission, reception, and spectrum management.Traditional approaches to signal generation and reconstruction, although effective in controlled environments, often struggle to cope with the challenges presented by real-world noisy conditions, hardware constraints, and limited access to large-scale datasets. In response to these limitations, this thesis explores the application of diffusion models—a class of generative models known for their ability to produce high-fidelity samples—to the domain of spectrogram generation for communication signals.

Different from conventional strategies to simulate …


Transient Thermal Finite Element Simulation For Process Modeling In Wire Arc Additive Manufacturing, Satya Sai Kumar Pilli Jan 2025

Transient Thermal Finite Element Simulation For Process Modeling In Wire Arc Additive Manufacturing, Satya Sai Kumar Pilli

Dissertations, Master's Theses and Master's Reports

This thesis presents the development of a transient thermal framework for Wire Arc Additive Manufacturing (WAAM) created using ANSYS Workbench. This study aims to understand the inherent properties and thermal behavior of WAAM by using the Finite Element (FE) simulation technique to reduce the need for experiments. Specifically, the transient thermal WAAM simulation framework uses the heat source Goldak model to understand the thermal behavior for a given voltage, initial temperature, and travel speed during the process to predict process temperature. The outcomes of this thesis aim to significantly decrease material waste and repetitive experiments and accelerate production process design …


Design Of Aluminum-Copper Alloy With Scandium In Solution, Austin M. Depottey Jan 2025

Design Of Aluminum-Copper Alloy With Scandium In Solution, Austin M. Depottey

Dissertations, Master's Theses and Master's Reports

The 2xxx series of precipitation-strengthened aluminum-copper alloys are commonly used in high-temperature applications (up to 300°C) where lightweight metals are required. Scandium additions to aluminum-copper alloys have gained recent academic interest due to improved high-temperature mechanical properties, by forming coarsening- resistant Al3Sc dispersoids and stabilization of θ′ precipitates. However, gaps in knowledge about the effects of scandium present a challenge to successful commercialization of aluminum-copper-scandium alloys. This work seeks to explore these knowledge gaps and ultimately design and test a commercially feasible aluminum- copper alloy with scandium. To better understand the processing conditions required to avoid the detrimental W-phase (Al8Cu4Sc), …


Machine Learning Design And Experimental Production Of Recycled Aluminum Alloys With Magnesium And Iron, Skylar Patten Jan 2025

Machine Learning Design And Experimental Production Of Recycled Aluminum Alloys With Magnesium And Iron, Skylar Patten

Dissertations, Master's Theses and Master's Reports

Recycling aluminum saves up to 95% of the energy required for primary production but introduces impurities such as iron that limit alloy performance. The Al-Mg-Fe system, though commercially used, remains underexplored. This work applies machine learning with Multi-Objective Bayesian Optimization (MOBO) using Thermo-Calc simulations to design Al-Mg-Fe-Si-Cu-Zn alloys with improved castability and reduced porosity. The optimization targeted freezing range, shrinkage, drag coefficient, and microstructural parameters, identifying compositions with high Mg, Si, and Cu and low Zn as optimal. Predicted alloys were experimentally cast and characterized, with yield strengths exceeding 95 MPa and elongation comparable to commercial 319 aluminum in the …


Computation Of Natural Relative Trajectories In The Elliptic Restricted Three-Body Problem, Dane Huck Jan 2025

Computation Of Natural Relative Trajectories In The Elliptic Restricted Three-Body Problem, Dane Huck

Masters Theses

"Humankind’s presence in deep space is certain to increase throughout future decades. Future missions will continue to exploit the complex dynamics making use of liberation point orbits. Along with this trend is the rise of small satellites ("small sats") and fractionated spacecraft in general. Compared to traditional monolithic spacecraft, small sats can often have higher maneuverability, be a fraction of the cost, and be more expendable in nature. The growing interest in these two areas drives the need for improvements in the area of relative motion in deep space. One obvious use of small sats in deep space is for …


Fetal Acidosis Prediction Using Attention Enhanced Convolutional Neural Networks, Anusha Adhikari Jan 2025

Fetal Acidosis Prediction Using Attention Enhanced Convolutional Neural Networks, Anusha Adhikari

Masters Theses

This study explores the integration of spectral mixtures of fetal heart rate (FHR) and uterine contraction (UC) signals to enhance the prediction of fetal acidosis, utilizing the CTU-CHB dataset. Several classification models were trained using two distinct oversampling techniques and inputs, demonstrating that models incorporating spectral mixtures significantly outperform those using raw signals. These models, particularly when combined with convolutional neural networks (CNNs) and attention mechanisms, achieved a notable F1-score of 0.98, with the highest model achieving an area under the Receiver Operating Characteristic (ROC) curve of 0.95. The research employs a variety of techniques including short-time Fourier transform and …


Emi Mitigation, Material Characterization, Transformer Equivalent Circuit Modeling, Reza Vahdani Jan 2025

Emi Mitigation, Material Characterization, Transformer Equivalent Circuit Modeling, Reza Vahdani

Masters Theses

Modern high-frequency electronic systems demand precise characterization and modeling techniques to ensure signal integrity and electromagnetic compatibility. This thesis presents three core studies focused on real-world challenges in high-speed and power electronics: EMI mitigation using 3D printed absorbers, wideband liquid dielectric characterization, and accurate transformer modeling.

The first study demonstrates a targeted approach to mitigating electromagnetic interference (EMI) in a commercial router. By using holography imaging to identify radiation hotspots, custom absorber structures were designed with commercially available materials, fabricated via 3D printing, and applied directly to emission sources. Radiated emission tests in a reverberation chamber showed up to 9 …


Ground Testing Of Cryogenic Environments In Vacuum Conditions, Lucas A. Scott Jan 2025

Ground Testing Of Cryogenic Environments In Vacuum Conditions, Lucas A. Scott

Masters Theses

The environment in the vacuum of space is unforgiving and ever-changing. Not only facing the lack of a protective atmosphere, but powerful radiation and extreme temperature ranges as well. Equipment destined for space must be hardened to withstand them. Just launching satellites that are theoretically able to survive these conditions is unfeasibly costly in the event of failure. Because of this, spacecraft must be tested in a simulated environment that can match the harsh climate in space. Therefore, it is the goal of the Gas and Plasma Dynamics Lab's (GPDL) to test and prove specific methods of recreating these conditions. …


Overpressure Waveform Comparison Of High Explosive, Methane, And Coal Dust Explosions, Frank James Schott Jan 2025

Overpressure Waveform Comparison Of High Explosive, Methane, And Coal Dust Explosions, Frank James Schott

Masters Theses

Methane and coal dust explosions remain a leading cause of catastrophic mining accidents, making it critical to understand their overpressure characteristics for better hazard modeling, mitigation, and regulation. Although high explosives (HE), flammable gases, and dusts have been studied separately, direct waveform comparisons in identical environments are rare. This study addresses that gap by comparing overpressure waveforms from HE, methane-air mixtures, and coal dust explosions to assess differences in peak pressure, impulse, rise time, and phase duration. Twenty-seven tests were conducted using standardized instrumentation and sensor arrays. Results showed that HE generated the highest peak pressures with short positive phases …


Frequency-Tracker And Power Supply For Piezoelectric Lunar Dust Removal Actuator, Praneeth Uddarraju Jan 2025

Frequency-Tracker And Power Supply For Piezoelectric Lunar Dust Removal Actuator, Praneeth Uddarraju

Masters Theses

"This work presents a reconfigurable phase-locked loop (PLL)-based control system for the resonant excitation of piezoelectric actuators aimed at automated removal of particulate contaminants from photovoltaic (PV) surfaces—particularly in extraterrestrial environments such as the lunar surface. Regolith or lunar dust buildup on solar panels is a serious hazard to the effectiveness of energy harvesting on extended missions. By using high-frequency structural excitation and inertial forces the suggested system removes surface impurities. Tunable Sallen-Key low-pass filters for reliable feedback conditioning are used in conjunction with a digitally implemented PLL on an FPGA (XLR8 platform) to precisely lock the drive frequency to …


Frozen Commons: Food Security And Food Sovereignty In Rural Alaskan Communities And Tribes, Catey Selby, Weiwei Mo Jan 2025

Frozen Commons: Food Security And Food Sovereignty In Rural Alaskan Communities And Tribes, Catey Selby, Weiwei Mo

Honors Theses and Capstones

This project explored the challenges, needs, and potential solutions related to food security and food sovereignty in rural Alaskan communities. These communities have long relied on traditional subsistence practices like fishing, hunting, and foraging, but those practices have been increasingly affected by climate change, regulatory restrictions, and commercial overfishing. Key issues identified included shorter hunting seasons, changes in animal migration, unsafe ice conditions, habitat loss, complex land ownership, and permitting barriers. Large-scale commercial fisheries also put additional pressure on subsistence resources, reducing access to traditional food sources.

The project focused on identifying key stakeholders—such as government agencies, tribal organizations, and …


Floating Offshore Structures: A Literature Review Of Current Technologies, Dynamic Behavior, And Energy Applications Post-2021, Stephen Michael Nolin Jan 2025

Floating Offshore Structures: A Literature Review Of Current Technologies, Dynamic Behavior, And Energy Applications Post-2021, Stephen Michael Nolin

Honors Theses and Capstones

No abstract provided.


Optimization Of Small-Scale Bioreactors For Increased Pdna Production And Yield, Laura M. Hills Jan 2025

Optimization Of Small-Scale Bioreactors For Increased Pdna Production And Yield, Laura M. Hills

Honors Theses and Capstones

No abstract provided.


Artificial Intelligence For Digital Deception: A Study On Detection, Generation, And Evaluation, Tasnim Akter Onisha Jan 2025

Artificial Intelligence For Digital Deception: A Study On Detection, Generation, And Evaluation, Tasnim Akter Onisha

College of Graduate Studies: Theses & Dissertations

The rapid advancement of artificial intelligence has significantly influenced digital media, enabling both the detection and generation of synthetic content. This thesis, titled Artificial Intelligence for digital deception: A Study on Detection, Generation, and Evaluation, explores AI’s role in digital deception through three distinct studies focused on facial expression analysis for deepfake detection, machine learning-based spam classification on cloud platforms, and the evaluation of generative AI state-of-the-art text to video models. The first study investigates the effectiveness of facial expression analysis in distinguishing between deepfake and genuine videos. Using Noldus FaceReader 7, participant’s emotional responses were analyzed while viewing deep-fake …


A Finite Volume-Based Approach For Modeling Hyperbaric Oxygen Therapy For Healing Chronic Wounds, Cade M. Layser Jan 2025

A Finite Volume-Based Approach For Modeling Hyperbaric Oxygen Therapy For Healing Chronic Wounds, Cade M. Layser

College of Graduate Studies: Theses & Dissertations

The current number of people in America with diabetes is approximately 38.4 million, that population is expected to rise to 54.9 million by 2030. Chronic wounds, which are characterized by impaired or stalled healing, are commonly associated with diabetes. These wounds if not treated properly can cause significant complications such as sepsis, infection, and gangrene which can lead to limb amputation or death of the patient. Limb amputations can be a large financial burden and significantly reduce the patient’s quality of life. The timely and efficient treatment of chronic wounds is essential to prevent adverse patient outcomes. Hyperbaric Oxygen therapy …


Defect Detection In Extrusion-Based Bio-Printed Constructs Using Video-Based Vibration Analysis, Md Anisur Rahman Jan 2025

Defect Detection In Extrusion-Based Bio-Printed Constructs Using Video-Based Vibration Analysis, Md Anisur Rahman

College of Graduate Studies: Theses & Dissertations

Bio-additive manufacturing has emerged as a transformative advancement in biomedical engineering, enabling the fabrication of complex biological structures. However, maintaining the precision and quality of printed constructs remains a significant challenge, particularly in applications such as bioprinted organ transplants. Among the key factors affecting structural integrity, dimensional inconsistencies and interlayer defects present major obstacles, potentially compromising mechanical stability and functionality. This study explores the detection of defects caused by variations in dimensional accuracy and layer-to-layer adhesion. To address these challenges, a video-based motion estimation technique is employed as a non-contact and non-destructive evaluation method. Traditional approaches, such as contact-based and …


Identification Of Corrosion Damage, Vibration, And Loose Conections In Aircraft Data Transmission Lines Using Reflected And Transmitted Signals; Formulation Of Vegetable Oil-Based Nanofluids As Cutting Fluids For Mql Machining, Saidanvardzhon Valiev Jan 2025

Identification Of Corrosion Damage, Vibration, And Loose Conections In Aircraft Data Transmission Lines Using Reflected And Transmitted Signals; Formulation Of Vegetable Oil-Based Nanofluids As Cutting Fluids For Mql Machining, Saidanvardzhon Valiev

Doctoral Dissertations

This research presents a novel Frequency Domain Transmitometry (FDT) method that uses transmitted signals (S21) to detect and characterize aircraft data transmission lines (ADTL) corrosion damage without additional reflectometry circuitry. Corrosion experiments were conducted according to ASTM G85-A5 over 14 weeks. Combined FDT and reflected signals (S11) analyses revealed distinct three-peak signatures associated with damage and corrosion. The square root of the Area Under the Curve (AUC) of the FDT damage peak and the Full Width at Three-Quarter Maximum (FW3QM) of the S11 damage peak is correlated with corrosion propagation depth and width. S11 signals were further used for vibration …


Process-Structure-Property Relationships In Laser Powder Bed Fusion Produced 17-4 Ph Steel, Ben Brown Jan 2025

Process-Structure-Property Relationships In Laser Powder Bed Fusion Produced 17-4 Ph Steel, Ben Brown

Doctoral Dissertations

Laser powder bed fusion (LPBF) is a metal additive manufacturing method that produces non-traditional microstructures as a result of the rapid solidification and thermal cycling inherent to the process. When using LPBF-produced material in application, these unique microstructures challenge the applicability of well-developed mechanical property databases achieved by conventional heat treatments. For wider adoption of this technology, a more holistic understanding is necessary on how process attributes develop material structure, which dictate mechanical properties. This dissertation explores the process structure-property relationships in LPBF 17-4 PH steel through systematic evaluation of atmospheric processing and heat treatment effects on microstructure and mechanical …


Application Of Artificial Intelligence Techniques To Improve Leadership Decision Making With Uncertainty, Michael David Parrish Jan 2025

Application Of Artificial Intelligence Techniques To Improve Leadership Decision Making With Uncertainty, Michael David Parrish

Doctoral Dissertations

"Every good leader is a good manager, but not every good manager is a good leader. The difference between the leader and the manager is critical decision-making. Today’s decision-making environment is characterized as Volatile, Uncertain, Complex, and Ambiguous (VUCA). With the exponential increase in the technical capabilities of systems, the human has become the weakest link in the use of such systems. To remain relevant, good leaders must continuously adapt to new advances in technology and processes.

The research contributions of this work provide several unique and novel solutions for leaders to utilize artificial intelligence tools to improve and optimize …


Raft-Based Polymer And Nanoparticle Materials For Traumatic Brain Injury Treatment And Diagnostics, Aaron Priester Jan 2025

Raft-Based Polymer And Nanoparticle Materials For Traumatic Brain Injury Treatment And Diagnostics, Aaron Priester

Doctoral Dissertations

"Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. Neurodegenerative diseases that develop post-TBI can be, in part, attributed to DNA and cell-damaging reactive oxygen species (ROS) and lipid peroxidation products (LPOx). This thesis focused on overcoming the limits of current TBI material treatment approaches by employing a RAFT (reversible-addition fragmentation chain transfer) polymer approach that incorporated novel therapeutic, diagnostic and peptide-targeting monomers. An improved nanoparticle synthesis approach was also developed. Thiol and thioether-containing monomers neutralize both ROS and LPOx while Gd-containing monomers with enhanced magnetic resonance imaging (MRI) contrast provide diagnostics and material tracking in …


Atmospheric Transport Of Radionuclides, Meteorological Data Mining & Synthesis For Site Data Supplementation, Ben Yao Sonpon Jan 2025

Atmospheric Transport Of Radionuclides, Meteorological Data Mining & Synthesis For Site Data Supplementation, Ben Yao Sonpon

Doctoral Dissertations

"This research aligns with the NRC's vision of implementing risk-informed decision-making to support its regulatory charter. The suite of tools developed includes automated procedures for data mining and extracting meteorological (met) data from various national and regional repositories. A second data analytics tool automates the process of data fusion into a uniform format while preserving data fidelity. Autocorrelations were then established, and correlation coefficients were calculated between the Callaway Nuclear Power Plant (Callaway) and nearby off-site weather stations. The complexity of these correlations depends on factors such as physical proximity, geographic features, and topology, potentially necessitating multivariate analysis (MVA). Furthermore, …


Transport And Plugging Behavior Of Co2-Resistant Preformed Particle Gels In High Conductive Channels For Conformance Control, Adel Alotibi Jan 2025

Transport And Plugging Behavior Of Co2-Resistant Preformed Particle Gels In High Conductive Channels For Conformance Control, Adel Alotibi

Doctoral Dissertations

"Improving oil recovery is essential with rising global oil demand and declining production in mature fields. CO2 flooding has been widely applied as a major Enhanced Oil Recovery (EOR) method due to its effectiveness in boosting oil recovery while enabling safe carbon storage in the subsurface. However, in fractured and highly heterogeneous reservoirs, CO2 often flows through paths of least resistance, leading to early breakthrough or quick excessive CO2 production and leaving substantial oil in unswept zones or areas. Traditional in-situ polymer gels have been applied to control CO2 flooding conformance, their performance has been varied, …


Mitigating Frost Heave And Thaw Weakening In Roads Using Wicking Geotextile, Javad Galinmoghadam Jan 2025

Mitigating Frost Heave And Thaw Weakening In Roads Using Wicking Geotextile, Javad Galinmoghadam

Doctoral Dissertations

"Excess water is known to be the primary cause of soil and foundation problems. In cold regions, water-related problems are exacerbated by seasonal freezing and thawing cycles. Frost heave and thaw weakening is the leading cause of premature pavement failure and consume considerable budgets of the Department of Transportations in cold regions. The first step to designing mitigation measures is the ability to predict frost heave under different conditions. This study aims to introduce a new method for quantifying frost heave using a prediction model based on the state surface approach. This proposed model addressed many inconsistencies and limitations of …