Engineering Commons^™

Computational Fluid Dynamics Simulation Of Battery Thermal Management System At The Pack Level In Electric Vehicles, Yifan Chen

Electronic Theses and Dissertations

Electric vehicles (EVs) rely heavily on lithium batteries due to their high energy density, despite their tendency to generate excess heat during operation. Managing this heat is crucial for safety and performance. Battery Thermal Management Systems (BTMS) are essential for maintaining optimal battery temperature and mitigating risks like short circuits. This article examines various cooling methods for BTMS, including air and liquid cooling, and discusses the selection of cooling media and layout configurations within battery packs (BPs). It also highlights the importance of combining multiple cooling methods for efficient heat dissipation. Emerging technologies like Phase Change Materials (PCMs) show promise …

Designing Ris-Assisted Uav 3d Trajectory Using Deep Reinforcement Learning, Linsong Li

Electronic Theses and Dissertations

Unmanned aerial vehicles (UAVs) are increasingly employed as temporary base stations or access points to facilitate data transfer between ground terminals (GTs). However, in urban environments, UAV-GT communication links often face challenges due to obstructions from buildings and other obstacles, resulting in reduced data transfer efficiency. Reconfigurable intelligent surfaces (RIS) provide a promising solution by reflecting signals to enhance communication quality between UAVs and GTs. This thesis addresses the critical challenge of responsive UAV trajectory optimization in RIS-assisted communication networks. A novel approach is proposed, integrating federated learning with reinforcement learning techniques, specifically Double Deep Q-Network (DDQN) and Deep Deterministic …

Evaluation Of Aashto Seismic Design For Reinforced Concrete Bridge Columns, Andrew Leroy Grismer

Electronic Theses and Dissertations

Bridge failure can be catastrophic resulting in casualties and limiting the accessibility and emergency response efforts. Ensuring a high level of ductility for bridge columns through sufficient design methods and detailing is the most important aspect of the modern seismic codes. Reinforced concrete (RC) bridge columns are widely used in multi-span bridges located in seismic regions of the nation due to their controlled ductility and durability. The objective of this study was to systematically evaluate the AASHTO seismic design requirements for RC bridge columns and to comment on whether current bridge code is sufficient and safe. An extensive literature review …

Optimizing Large Language Models And Multimodal Approaches For Biomedical Publication And Satellite Imagery, Youngsun Jang

Electronic Theses and Dissertations

This dissertation comprises two main sections: the first focuses on natural language processing (NLP) for extracting key information from scientific literature using large language models (LLMs), and the second addresses remote sensing for detecting natural disasters, such as floods, from satellite imagery using a multimodal approach. The first section investigates methods to enhance Transformer-based models in classifying and extracting information from biomedical scientific publications. Key contributions include the development of a custom dataset for classification and Question and Answering (Q&A) tasks, fine-tuning Transformer models like the Bidirectional Encoder Representations from Transformers (BERT) and addressing multi-span answer issues with the TAg-based …

Development Of Bed Shear Stress In Open Channel Flow In Smooth-To-Rough And Rough-To-Smooth Transitions, Linet Chietunda Paul

Electronic Theses and Dissertations

The study of flows over sudden change in bed roughness in open channels is important in understanding the flow dynamics of a developing boundary layer. Parameters such as shear velocity, mean flow velocity, turbulence intensity and the Reynolds stress distribution are critical in channel design optimization and predicting sediment transport. In this thesis, a detailed examination of the distribution of these parameters is undertaken in a rough-to-smooth and smooth-to-rough transition. Laboratory experiments were conducted on rough-to-smooth transition (Case A) and smooth-to-rough transition (Case B) in an open channel flume. Measurements of the fluid velocity fields at the centerline of the …

Development And Evaluation Of A Retrofittable Variable Rate Applicator Controller, Ahmed Abdalla

Electronic Theses and Dissertations

The need to optimize resource utilization while increasing crop productivity is paramount. This research proposes a Low-cost Retrofittable Variable Rate Applicator Controller (VRAC) that aims to leverage the adoption of Variable Rate Technologies. The controller operates via the Raspberry Pi platform, a Global Positioning System (GPS), a stepper motor drive, and an anti-slip wheel encoder. The VRAC allows precise, on-the-fly control of variable-rate application of farming inputs. It utilizes GPS with 10 cm accuracy to pinpoint geographic coordinates in real-time. A wheel encoder measures traveling speed with a slip-resistant wheel design for precise RPM readings. The Raspberry processes the data, …

Removal Of Phosphorous, Copper And Zinc From Stormwater Using Powdered Activated Carbon (Pac) Based Water Treatment Residuals, Foysol Mahmud

Electronic Theses and Dissertations

The main aim of this research was to evaluate the efficacy of Powdered Activated Carbon (PAC) based water treatment residual (WTR) in eliminating phosphorus (P), Copper (Cu), and Zinc (Zn) from stormwater. The characteristics of the PAC WTR were analyzed, and a series of batch and column tests were conducted to determine its capacity to remove P, Cu, and Zn from stormwater and synthetic solutions. The PAC WTR conformed to the Langmuir isotherm model, demonstrating P adsorption capacities of 3.51 mg/g at pH 5. Regarding Cu and Zn removal, the PAC WTR also adhered to the Langmuir isotherm model, showing …

Feasibility Study Of Managing Peak Cooling Loads To Achieve Energy Cost Reduction In A Northern Climate Campus, Mark Rizkalla

Electronic Theses and Dissertations

South Dakota State University Facilities and Services Office is facing the challenge of paying high electricity bills every year, the potential of campus growth will add more burden on the energy needed to cover this demand, especially in summer months when high cooling loads are added to the electrical loads which lead to the peak loads that costs SDSU a large amount of money. The purpose of this research is to study the feasibility of managing the peak loads to reduce energy costs by applying a suitable system that fits SDSU campus nature. The methodology used is studying the capability …

Structural Construction And Surface Modification Of Copper Current Collectors For Lithium Metal Batteries, Yaohua Liang

Electronic Theses and Dissertations

Graphene, a prevalent anode material in commercial lithium-ion batteries, has reached its theoretical capacity limit. The imperative is to develop high-capacity anode materials to meet the growing demand for energy density. Lithium metal, renowned for its exceptionally high theoretical specific capacity density (3680 mAh g-1) and low reduction potential (-3.04 V, relative to the standard hydrogen electrode), is commonly dubbed the "Holy Grail" for negative electrode materials in high-energy-density batteries. However, practical advancements in lithium metal anodes face obstacles like low Coulombic efficiency, limited cycle life, and heightened reactivity to the electrolyte and internal short circuits resulting from lithium dendrite …

Simulation Of Reacting Supersonic Flow In A Cavity Flameholder, Mohamed Benjelloun Touimi

Electronic Theses and Dissertations

Scramjet engines, or Supersonic Combustion Ramjets, are pivotal for achieving and maintaining hypersonic flight speeds. These engines leverage the high-speed airflow to compress and mix air and fuel for combustion. A significant challenge in Scramjet engine design is ensuring stable and efficient combustion within this high-speed environment. Cavity flameholders are crucial components that stabilize the combustion process by creating a subsonic region where the fuel-air mixture can ignite and sustain combustion. This research simulates this supersonic flow within the combustion chamber to accurately model and analyze the combustion dynamics. Various turbulence models, including RANS, and DES, are evaluated for their …

Evaluation Of Nutrient Removal From Modified Woodchips And Organic Matter Leached From Tree Leaves After Simulated Wildfire Thermal Alteration, Zengyue Wang

Electronic Theses and Dissertations

Nonpoint source pollution (NPS) from stormwater runoff, carrying a variety of contaminants, presents substantial challenges to water treatment processes and public health. Among the primary pollutants, phosphate and nitrate significantly contribute to the degradation of water quality, resulting in issues such as eutrophication and methemoglobinemia. Tree leaves, which are a major source of dissolved organic carbon (DOC) in forested watersheds and serve as a key fuel for wildfires, further exacerbate these challenges. Post-wildfire, the altered DOC is mobilized by precipitation, leading to stormwater runoff that impacts natural water bodies and complicates treatment processes, particularly through the formation of hazardous disinfection …

Evaluating The Impact Of Perceptual Loss In Generative Adversarial Models And Diffusion Models For Document Image Enhancement, Farzaneh Karimpour

Electronic Theses and Dissertations

Documents often suffer from various types of degradation which make them difficult to read and restrict OCR performance. This study investigates the effectiveness of perceptual loss in enhancing document image cleanup by comparing a GAN-based model and a diffusion model. In our experiments, we utilized the DE-GAN model as a GAN-based model and the NAF-DPM model as a diffusion model, both enhanced by incorporating perceptual loss. We then compared the results of both models and evaluated them by using the DIBCO 2013, DIBCO 2017, and H-DIBCO 2018 datasets revealed that our approach consistently outperforms existing state-of-the-art methods. Results showed that …

Comparative Analysis Of Deep Learning-Based Anomaly Detection Models For Gps Spoofing Detection, Hasan Mirzakhaninafchi

Electronic Theses and Dissertations

As autonomous vehicles (AVs) become integral to modern transportation, their susceptibility to cyber-attacks, particularly GPS spoofing, presents a serious security threat. This study addresses these challenges by applying a suite of deep learning models to enhance the detection of anomalous GPS signals. Focusing on autoencoder-based architectures, the proposed models such as long short-term memory-based variational autoencoder (LSTM-VAE), LSTM-based autoencoder (LSTM-AE), multilayer perceptron-based variational autoencoder (MLP-VAE), MLP-based Autoencoder (MLPAE), Stacked LSTM-based variational autoencoder (Stacked-LSTM-VAE), stacked LSTM-based autoencoder (Stacked-LSTM-AE), memory-augmented-LSTM-VAE (Mem-LSTM-VAE), and time-series-anomaly-detection-generative-adversarial-networks (TadGAN) were trained exclusively on authentic GPS data. This unsupervised learning approach which used for the above-mentioned models enables …

Computational Characterization Of Extracellular Electro-Osmotic Flow During Tissue Repair, Ashley Jorgensen-Blocker

Electronic Theses and Dissertations

Electrical stimulation (ES) therapy promotes the healing of chronic epidermal wounds and suppresses the degeneration of articular cartilage. Despite the success of ES therapy, the underlying mechanisms by which ES promotes tissue repair are largely unknown, preventing the standardization and optimization of treatments. One proposed mechanism involves electro-osmotic flow (EOF), electrically driven water flow generated within close proximity to the cell surface. EOF induces the transport of macromolecules and removes metabolic wastes and inflammatory molecules from these dense tissues through interstitial flow. This dissertation investigates the application of weak electric fields (EFs) to non-excitable cells and the generation of EOF …

An Integrated Hybrid P2p-Dr Networks For A Transactive Energy Market Platform Considering Electricity Network Constraints, Sheroze Liaquat

Electronic Theses and Dissertations

No abstract provided.

Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump

Electronic Theses and Dissertations

Biomanufactured 3D-organoids show promise for modeling and treating various conditions, particularly insulin-dependent diabetes mellitus (type-1 diabetes). Pancreatic islet organoids serve as sustainable sources of insulin-producing β-cells, potentially restoring insulin regulation in patients and providing a long-term solution for diabetes. Hydrogel droplet printing is an emerging technique in regenerative medicine due to its advantageous tunability and biocompatibility; however, challenges of consistency, quality control, and scalability persist. To address these issues, we developed a novel air-jetting based droplet bioprinting system for the generation of monodispersed alginate micro-droplets. The objective of this project was to incorporate human induced pluripotent stem cells (hiPSCs) into …

Large - Scale Manufacturing Of Fluorescent Perfluorocarbon Nanoemulsions For Oxygen Delivery, Anneliese Troidle

Electronic Theses and Dissertations

Over 100,000 Americans are currently waiting for a life – saving organ transplant, yet 17 patients die daily waiting for a transplant they will never receive [1]. Preservation of organs is an area that has seen innovation throughout the years and can improve rates of transplantation, yet vascularized composite allotransplantation preservation has not followed suit [2]. Current standard of care is use of electrolyte solutions such as Histidine – Tryptophan – Ketoglutarate (HTK) or University of Wisconsin (UW) Solution, yet these perfusates lack an oxygen carrying component [3]. Hemoglobin – based oxygen carriers (HBOCs) …

A Modular Framework For Surface-Embedded Actuation And Optical Sensing In Soft Robots., Paul Bupe Jr

Electronic Theses and Dissertations

This dissertation explores the development and integration of modular technologies in soft robotics, with a focus on the OptiGap sensor system. OptiGap serves as a simple, flexible, cost-effective solution for real-time sensing of bending and deformation, validated through simulation and experimentation. Working as part of an emerging category of soft robotics called Soft, Curved, Reconfigurable, Anisotropic Mechanisms, or SCRAMs, this research also introduces the Thermally-Activated SCRAM Limb (TASL) technology, which employs shape-memory alloy (SMA) wire embedded in curved sheets for surface actuation and served as the initial inspiration for OptiGap. In addition, the EneGate system is presented as a complementary …

A Study Of Group Effectiveness In A Virtual Reality Environment., Dalton Clay Sparks

Electronic Theses and Dissertations

Virtual Reality (VR) technology has revolutionized the study of team effectiveness, yet many studies in this domain lack a comprehensive approach, focusing narrowly on performance metrics. This thesis investigates VR team effectiveness by integrating traditional Team Effectiveness frameworks with VR-specific dynamics. Utilizing Data Envelopment Analysis (DEA) and Group Style Inventory (GSI), this study assesses teams within a VR environment, specifically a multiplayer submarine simulation game, IronWolfVR. Fifteen groups, totaling 45 participants, were observed for their collaborative gameplay, incorporating physiological measures (Heart Rate and Electrodermal Activity), team coordination dynamics, and various survey-based assessments (demographics, System Usability Scale, Simulator Sickness Questionnaire, and …

Quantifying Impacts Of Climate Change On Headwater Streamflow Regime In Robinson Forest: Insights From 35-Years Of Data Collection., Lauren Brown

Electronic Theses and Dissertations

Climate change may shift patterns of streamflow permanence in headwater systems by altering the frequency, magnitude, duration, timing, and rate of change of surface streamflow, impacting both local ecosystems as well as regional water budgets and availability. While much uncertainty surrounds modeling-based methods to quantify the impacts of climate change on water budgets, long-term hydrologic data collected from headwaters in experimental research forests serve as critical evidence to reduce such uncertainty. The objective of this study is to quantify shifts in frequency, magnitude, duration, timing, and rate of change of streamflow in two headwater catchments with relatively little recent disturbance …

Convolution And Autoencoders Applied To Nonlinear Differential Equations, Noah Borquaye

Electronic Theses and Dissertations

Autoencoders, a type of artificial neural network, have gained recognition by researchers in various fields, especially machine learning due to their vast applications in data representations from inputs. Recently researchers have explored the possibility to extend the application of autoencoders to solve nonlinear differential equations. Algorithms and methods employed in an autoencoder framework include sparse identification of nonlinear dynamics (SINDy), dynamic mode decomposition (DMD), Koopman operator theory and singular value decomposition (SVD). These approaches use matrix multiplication to represent linear transformation. However, machine learning algorithms often use convolution to represent linear transformations. In our work, we modify these approaches to …

Synergistic Strategies In Sinter-Based Material Extrusion (Mex) 3d Printing Of Copper: Process Development, Product Design, Predictive Maps And Models., Kameswara Pavan Kumar Ajjarapu

Electronic Theses and Dissertations

3D printing pure copper with high electrical conductivity and exceptional density has long been challenging. While laser-based additive manufacturing technologies suffered due to copper's highly reflective nature towards laser beams, parts printed via binder-assisted technologies failed to reach over 90% IACS (International Annealed Copper Standard), electrical conductivity. Although promising techniques such as binder jetting, filament, and pellet-based 3D printing that can print copper exist, they however still face difficulties in achieving both high sintered densities and electrical conductivity values. This is due to a lack of comprehensive understanding of property evolution from green to sintered states and the strategies that …

Quantification Of Tumor Biophysical Heterogeneity Through Mechanical And Ultrastructural Analysis., Bradley James Mahaffey

Electronic Theses and Dissertations

Glioblastoma (GBM) is a highly invasive, aggressive brain cancer that carries a median survival of 15 months. This poor prognosis is due, in part, to its resistance to standard therapeutic intervention. Recent studies have demonstrated that tumor heterogeneity plays a critical role in facilitation therapy resistance by mediating tumor adaptation through microenvironmental cues. Efforts to describe these microenvironmental differences may aid in the development of strategies to combat resistance. GBM can be separated into two distinct regions – a core and a rim, which are thought to drive specific aspects of tumor evolution. The core is proliferative as evidenced by …

Automated Usability Evaluation Utilizing Log Files And Data Mining Techniques., Sima Shafaei

Electronic Theses and Dissertations

Usability evaluation is one of the essential aspects of software production. This evaluation should be done during the entire life cycle of a software application, from pre-production to production and post-production. However, the collection and evaluation of usability data can be a very challenging, time-consuming, and expensive task to be conducted manually, particularly for certain types of products and working conditions. These challenges may include the need to recruit participants fully engage and motivate them during evaluation, and factor in environmental conditions. Other challenges may include collecting data in real-world environments, especially when the users are geographically dispersed, minimizing evaluator …

Investigating Mems Devices In Flow Conditions Relevant To Flow-Through Systems., Mohammad Shafquatul Islam

Electronic Theses and Dissertations

Advancements in microscale actuating technologies has substantially expanded the possibilities of interacting with the surrounding environment. Microstructures that deflect in response to mechanical forces are one of the largest application areas of microelectromechanical systems (MEMS). MEMS devices, functioning as sensors, actuators, and support structures, find applications in inertial sensors, pressure sensors, chemical sensors, and robotics, among others. Driven by the critical role of catalytic membrane reactors, this dissertation aims to evaluate enzyme activity on polymeric membranes and explore how fabrication methods from the field of Electrical and Computer Engineering (ECE) can incorporate sensing and actuation into these porous surfaces. Toward …

Adaptive Personalized Drug Delivery Method For Warfarin And Anemia Management: Modeling And Control., Affan Affan

Electronic Theses and Dissertations

Personalized precision medicine aims to develop the appropriate treatments for suitable patients at the right time to obtain optimal results. Personalized medicine is challenging due to inter- and intra-patient variability, narrow therapeutic window, the effect of other medications, comorbidity (more than one disease at a time), nonlinear patient dynamics, and time-varying patient dose response characteristics which include bleeding (internal and external). This research aims to develop a framework for an adaptive personalized modeling and control method with minimum clinical patient specific dose response data for optimal drug dosing. The proposed methodology is applied to anemia and warfarin management. It is …

Design, Fabrication, And Integration Of Robotic Skin Sensors For Human Robot Interaction., Olalekan Olakitan Olowo

Electronic Theses and Dissertations

Enhancing physical human-robot interaction in modern robotics relies on refining the tactile perception of robot skin sensors. This research focuses on crucial aspects of the development process, including fabrication techniques, miniaturization, and integration for a more efficient collaborative human-robot interface. The fabrication process of robot skin sensors, designed to mimic human skin, is explored both within and outside cleanroom environments. An enhanced technique is presented to increase fabrication yield and create more miniaturized sensor designs with feature sizes in the tens of microns. These sensors function as piezoresistive arrays using organic polymers like PEDOT: PSS as the pressure-sensing medium. Various …

Thermo-Mechanical Instabilities In Next-Generation Friction Materials In High-Speed Sliding Systems, Kingsford Koranteng

Electronic Theses and Dissertations

For centuries, the manufacturing industry has incorporated metals like copper into friction materials to enhance thermal properties and minimize thermo-mechanical instabilities (TMI) in high-speed sliding systems. Unfortunately, these metals have adverse environmental effects due to the emission of hazardous particulate matter. As a result, there is a growing movement towards adopting next-generation friction materials as an alternative solution.

The study begins by conducting experimental and numerical investigations to examine the instabilities found in metal-based friction materials. The primary objective is to utilize the insights gained from the investigations to computationally explore effective strategies for mitigating various instabilities that may arise …

Molecular Dynamics Study Of Characterization In Metal-Free Friction Materials, Yizhan Zhang

Electronic Theses and Dissertations

Metallic friction materials currently used in industry may adversely impact the environment. Substitutions for metals in friction materials, on the other hand, can introduce operational safety issues and other unforeseeable issues such as thermal-mechanical instabilities and insufficient strength. In view of it, this dissertation focuses on developing different kinds of materials from simple structure to complex structure and evaluating the material properties with the assistance of molecular dynamics (MD) tools at the nano scale.

First, the concept of the contacted surfaces in friction at the atomic scale was introduced in order to get accurate understanding of the friction process compared …

Quantitative, Photocurrent Multidimensional Coherent Spectroscopy, Adam Halaoui

Electronic Theses and Dissertations

Multidimensional coherent spectroscopy (MDCS) is a quickly growing field that has a lot of advantages over more conventional forms of spectroscopy. These advantages all come from the fact that MDCS allows us to get time resolved correlated emission and absorption spectra using very precisely chosen interactions between the density matrix and the excitation laser. MDCS spectra gives the researcher a lot of information that can be extracted purely through qualitative analysis. This is possible because state couplings are entirely separated on the spectra, and once we know how to read the data, we can see how carriers transport in the …