Engineering Commons^™

Directional Speaker Poster, Eugene Ng, Bryan Wong, Ruhaan Das

Student Works

Changi Airport is set to expand with a new terminal, Terminal 5. Currently, many of the airport's processes are manual, requiring a high dependence on staff. This proposal aims to incorporate automation and AI for a smoother passenger experience.

Integrated Dynamic Airline Route And Schedule Optimization, Bayan Begaliyeva

Student Works

By harnessing real-time and historical data in conjunction with advanced AI technologies, this project revolutionizes route and schedule planning, leading to enhanced efficiency, cost reduction, and an improved passenger experience.

Electrolyte Synthesis And Engineering For Alkali Metal Batteries, Yiwen Zhang

Dartmouth College Ph.D Dissertations

Batteries have been in increasing demand over the last decade for portable electronic devices, electric vehicles, and grid-scale energy storage systems. While the electrode materials define the characteristic features of a battery system, the composition of the electrolyte is of critical importance and needs to be engineered for different battery systems to ensure superior electrochemical performance. In this thesis, the basic functionality and fundamental mechanism of the electrolytes in battery systems are first introduced. Then, three major electrolyte engineering strategies are demonstrated, including electrolyte composition formulation, electrolyte-electrode component modification, and function-oriented electrolyte design. Firstly, the low-temperature capacity restraint of lithium …

Pore-Resolving Simulations Of Biomass Char Particle Combustion, Dongyu Liang, Simcha L. Singer

Mechanical Engineering Faculty Research and Publications

Biomass char morphology affects combustion behavior at the particle scale for zone II conditions, in which both heterogeneous reaction and intra-particle diffusion govern the overall rate. Furthermore, particle-scale processes affect reactor-scale outputs, and reactor-scale simulations are sensitive to particle-scale models. However, most char particle combustion models employ coarse-grained, effective-continuum approaches, which treat all porosity at the subgrid-scale. Effective-continuum approaches are not valid or accurate in the presence of large, irregular pores which can approach the size of the particle. A 3-D, pore-resolving CFD simulation approach using real biomass char particle geometries obtained from X-ray micro-computed tomography (micro-CT) is therefore used …

Triangular Fin Array Passively Actuated By Bimetallic Coils For Cubesat Thermal Control, Josh Cannon, Rydge B. Mulford, Brian D. Iverson

Faculty Publications

CubeSat thermal control can be especially demanding due to volume and size constraints, high power dissipation per unit surface area, and highly variable internal and external heat loads. As such, CubeSat developers must rely on thermal control systems that meet the specific requirements of their mission and environmental conditions. Deployable radiators enable satellites to increase their radiative surface area and to reveal highly emissive surfaces during times when increased heat rejection is desired. In colder conditions, when decreased heat loss is preferable, the radiators can be stowed. Passive thermal control systems are unpowered and can increase system reliability by not …

Low-Fidelity Design Optimization And Parameter Sensitivity Analysis Of Tilt-Rotor Evtol Electric Propulsion Systems, Tyler Critchfield, Andrew Ning

Faculty Publications

Urban air mobility requires a multidisciplinary approach to tackle the important chal- lenges facing the design of these aircraft. This work uses low-to-mid fidelity tools to model rotor aerodynamics, blade structures, vehicle aerodynamics, and electric propulsion for a tilt-rotor electric vertical takeoff and landing (eVTOL) aircraft. We use gradient-based design optimization and extensive parameter sensitivity analysis to explore the design space and complex tradeoffs of tilt-rotor distributed electric propulsion systems.

A Coupled Source Panel, Actuator Line, And Viscous Vortex Particle Method In An O(N) Scheme, Ryan Anderson, Andrew Ning

Faculty Publications

Wake interactions play a significant role in aerodynamics. However, common modeling approaches are either expensive or lack fidelity, making them unreliable or difficult to use in the design process. The vortex particle method can capture the relevant physics effectively, but imposing boundary conditions with solid surfaces in a computationally efficient way is challenging. We explore two possible methods of imposing solid surface boundary conditions of vortex particle simulations. The first, a novel variation on a pure particle approach, is easy to implement but is moderately expensive, and suffers from some numerical instability. The second, source panels accelerated with a fast …

Aerostructural Predictions Combining Fenics And A Viscous Vortex Particle Method, Ryan Anderson, Andrew Ning, Ru Xiang, Sebastiaan P. C. Van Schie, Mark Sperry, Darshan Sarojini, David Kamensky, John T. Hwang

Faculty Publications

Electric Vertical Takeoff and Landing (eVTOL) aircraft experience complex, unsteady aerodynamic interactions between rotors, wings, and fuselage that can make design difficult. We introduce a new framework for predicting aerostructural interactions. Specifically, we demonstrate the coupling of a finite element solver with Reissner-Mindlin shell theory for computing deflections and a viscous vortex particle for capturing wakes. We perform convergence studies of the aerodynamics and the coupled aerostructural model. Finally, we share some preliminary results of the dynamic aeroelastic response of Uber’s eCRM-002 main wing, and share some qualitative observations.

Sparsity For Gradient-Based Optimization Of Wind Farm Layouts, Benjamin T. Varela, Andrew Ning

Faculty Publications

Optimizing wind farm layouts is an important step in designing an efficient wind farm. Optimizing wind farm layouts is also a difficult task due to computation times increasing with the number of turbines present in the farm. The most computationally expensive part of gradient- based optimization is calculating the gradient. In order to reduce the expense of gradient calculation, we performed a study on the use of sparsity in wind farm layout optimization. This paper presents the findings of the sparsity study and provides a method to use sparsity in wind farm layout optimization. We tested this sparsity method by …

Isogeometric Boundary-Conforming Body-In-White Crash Model Construction, Analysis, And Comparison With Fem Model, Kendrick M. Shepherd

Faculty Publications

In this paper, we discuss model generation to rebuild the body-in-white of a 1996 Dodge Neon finite element model into a isogeometric conforming analysis-suitable crash model. We then perform the first known boundary-fit isogeometric body-in-white crash analysis of the vehicle and compare results achieved by traditional finite element methods. Results indicate the value and potential of high-order meshes in analysis.

Machine Learning Prediction Of Dod Personal Property Shipment Costs, Tiffany Tucker, Torrey J. Wagner, Paul Auclair, Brent T. Langhals

Faculty Publications

U.S. Department of Defense (DoD) personal property moves account for 15% of all domestic and international moves - accurate prediction of their cost could draw attention to outlier shipments and improve budget planning. In this work 136,140 shipments between 13 personal property shipment hubs from April 2022 through March 2023 with a total cost of $1.6B were analyzed. Shipment cost was predicted using recursive feature elimination on linear regression and XGBoost algorithms, as well as through neural network hyperparameter sweeps. Modeling was repeated after removing 28 features related to shipment hub location and branch of service to examine their influence …

Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek

Publications

The design of an inward-turning, high-speed, three-dimensional streamline traced intake is presented from osculating axisymmetric theory. To satisfy the osculating intake design criteria, a stitched Busemann diffuser and Internal Conical Flow-A solution is used as the basic isentropic compressive streamline. This new contour provides efficient compression, high flow uniformity, and straight leading edge shocks of equal strength. Additionally, a novel method for constructing the inlet cowl is presented. The combined process leads to a new method of high-speed intake design. A generic shape-transitioned intake is constructed and named the Indiana Inlet for the Indiana universities that contributed to the project. …

Investigation Of Microstructurally Dependent Mechanical Properties Of Cold Sprayed Copper Using Correlative Microscopy, Quintin Otto

UNF Graduate Theses and Dissertations

This project employs multi-instrument materials characterization to analyze material made with the “Cold Spray” additive manufacturing process. Cold spray is an emerging additive manufacturing technique with unique benefits resulting from its low temperature adhesion process induced by plastic deformation. Metallic powder collides at high speeds creating three dimensional materials and coatings without the need for melting. Copper cold sprayed specimens were analyzed using a series of imaging techniques to characterize the microstructure at varying levels of detail and magnification. Scanning electron microscopy and electron back scattered diffraction were paired with microhardness testing to generate a correlative comparison between microstructure and …

Analysis Of Pervious Oyster Shell Habitat (Posh) Unit Performance Using Computational Fluid Dynamics, Lauren E. Cope

UNF Graduate Theses and Dissertations

In recent years, pervious oyster shell habitat (POSH) units have been developed and deployed as part of living shoreline projects in Northeast Florida. POSH units are modular artificial oyster reef structures made from cement and recycled oyster shells. POSH units aim to attenuate wave energy, trap sediment, restore salt marsh habitat, and improve oyster recruitment. Previous studies demonstrated the units’ ability to attract oyster larvae and reduce shoreline bed stress in some areas. This paper looks to further understand the effect of POSH unit placement on bed stress under boat wake conditions using computational fluid dynamics (CFD). Results indicated that …

Frequency Analysis Of A New Empirical Model To Predict Underwater Transmission Loss During Impact Pile Driving, Mariam S. Makoleo

UNF Graduate Theses and Dissertations

Over the years, anthropogenic noise generated by pile driving activities has increased, posing a significant concern for marine organisms and their ecosystems. This study aims to entail a comprehensive frequency analysis of a new empirical model to predict underwater transmission loss during impact pile driving. To achieve this objective, extensive data collection was undertaken, and spectral and frequency analyses were conducted to examine the frequency content and attenuation patterns of the sound. The results of the study reveal that sound attenuation is frequency-dependent. Notably, low frequencies, typically below 100 Hz, and very high frequencies, approximately 10 kHz, were found to …

Analyzing Physiological Signals During The Menstrual Cycle: Introducing An Application Of Circular Statistics, Krystal D. Sides

UNF Graduate Theses and Dissertations

Physiological signals are used in engineering and the sciences to determine the state of functionality of certain physiological systems such as the human endometrium. Many women use the basal body temperature method to track ovulation, or their fertile window. However, temperature tracking alone is subject to environmental factors. Non-invasive wearable devices can be tools in recording cycle-related physiological features relevant to women’s health research. This research uses the Empatica E4 wristband to track changes in the physiological features during sleep across the menstrual cycle of ovulating and non-ovulating females. Due to the cyclic nature of menstrual cycles, analytic solutions to …

Sustainable Transportation: Behavioral Analysis Of Working-From-Home And Electric Vehicles Adoption, Zeinab Bayati

UNF Graduate Theses and Dissertations

Sustainable transportation plays a crucial role in mitigating environmental impacts, and this study examines two key aspects, namely working from home (WFH) and the adoption of electric vehicles (EVs), in the context of promoting sustainable practices.

The first part of this thesis focuses on how people's perceptions towards working from home have changed as a result of their experiences during COVID-19. To analyze these changes, a random parameter logit (RPL) model is developed based on a nationwide public dataset collected during the pandemic in the United States. Dependent variable of the model is constructed through comparing data from the first …

Ovulation Prediction Using Random Forest Algorithm On Physiological Data, Kimberly D. Laynes

UNF Graduate Theses and Dissertations

Human infertility rates are on the rise -- studies have shown that one in every four women have trouble conceiving and every year those rates are rising [Halleran22]. This trend motivates procedures such as in-vitro fertilization (IVF) and intrauterine insemination (IUI) to produce a pregnancy. Such procedures are not only intricate and expensive but also carry potential unintended consequences for women's physical and mental well-being. A more profound comprehension of the menstrual cycle and its multiple phases, particularly detecting the ovulation period itself, promotes optimized treatment outcomes and reduces associated risks. To facilitate ovulation detection, new sensing technologies built into …

Predicting Florida's Extreme Wind Events: A Deep Learning Approach, Irene Josephat Byemerwa

UNF Graduate Theses and Dissertations

Extreme wind events, such as hurricanes and tropical storms, have devastating impacts on infrastructure, economy, and public safety in Florida. Traditional predictive methods, linear regression, logistic regression, and autoregressive integrated moving-average (ARIMA) models have limitations in accounting for non-stationarity and nonlinearity in meteorological data, leading to less accurate predictions. The primary objective of this study is to leverage the capabilities of deep learning algorithms, specifically, Feedforward Neural Networks (FFNNs), to develop a predictive model that outperforms traditional predictive methods in forecasting extreme wind events in Florida. The deep learning model was trained, validated, and tested using historical wind speed data …

Development Of High Kinetic Inductance Superconducting Nanowire Devices On High Permittivity Strontium Titanate Substrates, Jamie Timmons

UNF Graduate Theses and Dissertations

This thesis involves the fabrication and characterization of devices made from two different superconducting materials: yttrium barium copper oxide (YBCO), a high-TC complex oxide, and niobium nitride (NbN), a low-TC transition metal nitride. Both types of devices are fabricated on strontium titanate substrates, which provides a good lattice match to YBCO and also an extremely large permittivity at low temperature. We demonstrate that wet etching of YBCO thin films via bromine can be a viable microfrabriation technique for the material. Using approximately 35 nm thick epitaxially grown YBCO on an STO substrate, we were able to fabricate YBCO “microwires” with …

Development Of Practical Assessment Techniques For Sinkhole Potential In Florida Based On Sinkhole Vulnerability Indices, Sylvia Pesha

UNF Graduate Theses and Dissertations

Sinkholes are natural geohazards prevalent in Florida's distinctive karst geology, posing risks to public safety, infrastructure, and groundwater integrity. Considering the increasing frequency of sinkhole occurrences in Florida due to land development in vulnerable soils, understanding the potential for sinkhole occurrence can aid in the identification of high-risk locations and inform effective mitigation strategies. Researchers have developed three point-based indices to be used when assessing the vulnerability a project site has to sinkhole formation based on the encountered subsurface conditions. Engineers have historically used an index based on the subsurface layer thicknesses, called the Raveling Index (RI). In recent years, …

Object Tracking With An Event Camera, Nader Ahmed , '23, Rezhwan A. Kamal , '23

Senior Theses, Projects, and Awards

In this project, an event-based camera was used to develop a functional proof of concept for a procedural 3-D cube tracking system. Hough space shape detection was used to track the position of cube edges in the image space, and an optimization-based algorithm was used in conjunction for finding the pose of the cube. Additionally, a ghosting effect was seen following the trailing edge of events. A sensor model was developed for simulating and investigating this phenomenon.

Synthesis Of High-Temperature Ybco Superconductors, Simon Ji , '23

Senior Theses, Projects, and Awards

Superconductors are a fascinating class of materials that seem to defy physics. For my project, I attempted to create one of the most famous types of superconductor, Yttrium Barium Copper Oxide (YBCO), using commonly available chemicals found online and equipment that already exists on campus. This report gives a short description of the theory behind superconductors, and outlines the synthesis procedures I followed that involved citrate pyrolysis and high-temperature treatment using a tube furnace. I succeeded in creating YBCO samples that exhibited superconducting behaviors, and also designed a small magnetic track that can be used for demonstration purposes.

Mapping And Navigation With The Fetch Robot, Dorothy Najjuma Kamya , '23

Senior Theses, Projects, and Awards

The goal of this project was to design software for the Fetch mobile manipulator robot to create a map of the second floor of Singer Hall, be able to locate itself on the map generated and navigate to a given position on the map. This was implemented within the Gazebo simulator initially, and then uploaded to the robot. The project can be extended to make the Fetch robot an interactive tour guide for Singer Hall, or to perform low-level tasks around the building like calling the elevator or carrying small objects between rooms. The interactive tour guide functionality is a …

Inverting Kite Structure & Stability For Airborne Wind Energy, Joshua Vandervelde , '23

Senior Theses, Projects, and Awards

Airborne Wind Energy (AWE) is an emerging method of extracting clean energy from high altitude airstreams with tethered kites, but inflated kites presently lack actuators to control lift and roll. Inverting wings show promise at providing both forms of maneuverability and have so far been researched to validate lift vector manipulation. This capstone project aims to demonstrate the applicability of inverting wings to roll control by segmenting an inflated wing into sections with independent inversion control, inducing a roll moment. The preliminary results from this novel wing design suggest that double inversion does indeed facilitate roll control, but further roll …

Max Fit Event Management With Salesforce, Akshay Dagwar

Electronic Theses, Projects, and Dissertations

MAX FIT Gym is looking for an event management software program to help manage activities very efficiently, along with attendees and environmental statistics. The event management program is developed and deployed using the Salesforce platform. MAX FIT can efficiently create, edit, and remove events and send email alerts to clients. This task operated on opportunities captured under MAX FIT, including all clients, and prepared information in the Salesforce cloud. This also includes product inventory with various varieties of protein products, and business owners can also add more products to their inventory. In the event management program, the event addresses within …

Breast Density Classification Using Deep Learning, Conrad Thomas Testagrose

UNF Graduate Theses and Dissertations

Breast density screenings are an accepted means to determine a patient's predisposed risk of breast cancer development. Although the direct correlation is not fully understood, breast cancer risk increases with higher levels of mammographic breast density. Radiologists visually assess a patient's breast density using mammogram images and assign a density score based on four breast density categories outlined by the Breast Imaging and Reporting Data Systems (BI-RADS). There have been efforts to develop automated tools that assist radiologists with increasing workloads and to help reduce the intra- and inter-rater variability between radiologists. In this thesis, I explored two deep-learning-based approaches …

Energy-Efficient Hmac For Wireless Communications, Cesar Enrique Castellon Escobar

UNF Graduate Theses and Dissertations

This thesis introduces the Farming Lightweight Protocol (FLP) optimized for energy-restricted environments that depend upon secure communication, such as multi-robot information gathering systems within the vision of ``smart'' agriculture. FLP uses a hash-based message authentication code (HMAC) to achieve data integrity. HMAC implementations, resting upon repeated use of the SHA256 hashing operator, impose additional resource requirements and thus also impact system availability. We address this particular integrity/availability trade-off by proposing an energy-saving algorithmic engineering method on the internal SHA256 hashing operator. The energy-efficient hash is designed to maintain the original security benefits yet reduce the negative effects on system availability. …

Analysis Of Underwater Noise Due To Pile Driving In Florida Using Individual Hammer Blows, Consolatha Constantine Mushi

UNF Graduate Theses and Dissertations

In recent years, the potential impact on marine organisms of sound waves generated by pile driving has become a growing concern. Previous research in this field has predominantly relied upon single-strike averages to analyze underwater sound data. However, it was unclear from these analyses if or how much attenuation may vary during typical pile drives. This study involved collecting sound data from multiple locations during a given pile driving operation at the same time and used these data to analyze sound decay from each hammer blow individually. In addition to this, computational fluid dynamics (CFD) was used to better understand …

Modified Reactive Sputter Deposition Of Titanium Nitride Thin Films Via Hipims With Kick-Pulse And Improvement Of The Structure-Zone Model, Andrew Miceli

UNF Graduate Theses and Dissertations

Direct current (DC) and radio frequency (RF) sputtering methods have been commonplace in industry for several decades and widely studied in literature. Hard films of nitrides, such as titanium nitride (TiN), have been deposited using reactive DC sputtering onto cutting tools and medical devices extensively as well. For these applications, the films require excellent adhesion, high density, and high hardness. High-Power Impulse Magnetron Sputtering (HIPIMS) has emerged over the last several years as a method to produce films with increased density and mechanical properties. Process-structure-property relationships for reactive HIPIMS are not yet well developed. Additionally, conventional HIPIMS suffers from relatively …