Engineering Commons^™

Flexible Cu Nanostructured Laser-Induced Graphene Electrodes For Highly Sensitive And Non-Invasive Lactate Detection In Saliva, Anju Joshi, Gymama Slaughter

Center for Bioelectronics Publications

A scalable and facile fabrication strategy is presented for developing a flexible, nanostructured, non-enzymatic electrochemical sensor for lactate detection based on copper-modified laser-induced graphene (CuNPs/LIG). A one-step electrodeposition process was employed to uniformly decorate the porous LIG framework with copper nanostructures, offering a cost-effective and reproducible approach for constructing enzyme-free sensing platforms. Scanning electron microscopy and energy-dispersive X-ray spectroscopy confirmed dense Cu nanostructure loading and efficient interfacial integration across the conductive LIG surface. The resulting CuNPs/LIG electrode exhibited excellent electrocatalytic performance, achieving a sensitivity of 8.56 μA µM⁻¹ cm⁻² with a low detection limit of 42.65 …

Recent Advances In Triboelectric Nanogenerators For Biomedical And Cardiovascular Monitoring, Amit Sarode, Jegan Rajendran, Gymama Slaughter

Center for Bioelectronics Publications

Triboelectric nanogenerators (TENGs) have emerged as versatile self-powered platforms for wearable and implantable biomedical sensing, offering an alternative to battery-dependent electronic devices. By converting biomechanical energy from physiological motion into electrical signals, TENGs enable simultaneous energy harvesting and active sensing within flexible, lightweight, and biocompatible architectures. This review summarizes recent advances from 2020 to 2025 in triboelectric nanogenerator (TENG)-based cardiovascular monitoring. The discussion focuses on material systems, device configurations, sensing mechanisms, and applications including pulse detection and cuffless blood pressure estimation. Representative studies are compared to highlight emerging trends in wearable and self-powered sensing technologies. However, differences in experimental conditions, …

Linker-Free Gold-Sputtered Tapered Optical Fiber Plasmonic Sensors For High-Sensitivity Refractive Index Detection In Microfluidic Platforms, Erem Ujah, Gymama Slaughter

Center for Bioelectronics Publications

Gold-sputtered tapered optical fiber (Au-TOF) sensors were developed for high-sensitivity refractive-index (RI) detection using aqueous glucose standards spanning 1.33–1.41 RIU (0–50% w/v). The sensors were fabricated using a reproducible workflow combining flame-brushing tapering, plasma surface preparation, and rotational magnetron sputtering, enabling azimuthally uniform gold coatings without the use of thiol or sulfur linker chemistries. Two sputtering durations (24 s and 30 s) were investigated to examine thickness-dependent plasmonic coupling and sensing performance. Optical measurements were conducted using a broadband supercontinuum source and compact spectrometer within a 20 µL microfluidic sensing chamber. Increasing glucose concentration produced a monotonic decrease in transmission …

A Portable Potentiostat Integrated With A Pt/Zno/Lig Electrode For Non-Enzymatic Glucose Detection, Reagan Aviha, Gymama Slaughter

Center for Bioelectronics Publications

Continuous glucose monitoring is critical for effective diabetes management; however, conventional benchtop potentiostats are bulky, costly, and unsuitable for decentralized point-of-care (PoC) applications. To address these limitations, this work presents a miniaturized, low-cost electrochemical sensing platform integrating a non-enzymatic glucose sensor with a portable potentiostat. The sensing electrode is based on laser-induced graphene modified with zinc oxide and platinum nanostructures via electrodeposition to enable sensitive glucose detection under physiological conditions. A custom-designed portable potentiostat was developed to control electrode potentials and perform electrochemical measurements, and its performance was experimentally validated against a commercial Metrohm system. Glucose detection was evaluated using …

Ai-Driven Prediction And Reconstruction Of Missing Cased-Hole Logs For Improved Well System Understanding, Samuel Avilez Martinez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Well logging is a fundamental technique in formation evaluation providing continuous, real-time measurements of geological and petrophysical properties within a well. Through the systematic analysis of well logs, engineers and geoscientists can accurately determine critical formation characteristics, including porosity, permeability, lithology, and fluid composition. Well logging is fundamental for making informed decisions and reducing uncertainties in the exploration and development of oil and gas reservoirs.

Despite its significance, the acquisition of reliable well log data in oil and gas wells is often compromised by various operational, mechanical, and formation-related challenges, as well as pressure, fluid, and equipment constraints. In high-risk …

Elucidating Structure–Reactivity Relationships In Ni-Catalyzed Co2 Methanation, Majed Alam Abir

Graduate Theses, Dissertations, and Problem Reports (ETD)

The catalytic hydrogenation of carbon dioxide (CO₂) to methane represents a promising strategy for carbon utilization and renewable energy storage within power-to-gas systems. When coupled with hydrogen derived from renewable electricity, CO₂ methanation enables the conversion of intermittent energy sources into storable and transportable chemical fuels compatible with existing natural gas infrastructure. Nickel-based catalysts have emerged as leading candidates for this reaction due to their high activity towards CO₂ methanation, abundance, and cost. However, the performance and long-term stability of Ni catalysts are strongly influenced by catalyst support properties, Ni nanoparticle size, and promoter effect, and …

Real-Time Lidar-Based Vehicle Detection Using Pointpillars For Connected And Automated Vehicle Applications, Jared Townsend Behr

Graduate Theses, Dissertations, and Problem Reports (ETD)

This work explores the implementation of a real-time LiDAR processing model for autonomous vehicle design. Automotive perception systems are becoming increasingly important as Advanced Driver Assistance Systems (ADAS) and Connected and Automated Vehicle (CAV) technologies continue to progress toward higher levels of autonomy. Reliable perception is paramount for autonomous features, such as adaptive cruise control (ACC), where identifying and tracking a lead vehicle is a safety critical task.

Many production ADAS perception systems primarily rely on radar and camera sensors for object detection and sensor fusion. These sensors work well to achieve classification and accurate distance detections; however, they are …

Swarm Of One: Self-Organization In Multicellular Robots, Trevor Riley Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Designing robots traditionally relies on centralized, top-down methods that constrain adaptability and resiliency, producing systems optimized for specific tasks. However, such systems often fail in complex environments, such as extraterrestrial, disaster, or natural settings, where designers cannot foresee every scenario a robot may encounter. Achieving autonomy in these contexts requires robots that are resilient and capable of adapting to the unknown. Multicellular organisms exhibit this adaptability through self-organization, where complex structures and behaviors emerge from local interactions among their cells. Such organisms can be viewed simultaneously as a single entity and a swarm of cooperating cells, i.e., a Swarm-of-One.

This …

Development And Validation Of A Multi-Output Neural Network-Based Virtual Temperature Sensor For Electric Vehicle Thermal Management, Dalton Michael Wiggins

Graduate Theses, Dissertations, and Problem Reports (ETD)

Battery electric vehicles (BEVs) rely on accurate thermal management to ensure component performance, efficiency, safety, and long-term durability. Critical propulsion system components, including electric motors and high-voltage battery packs, are commonly monitored using physical temperature sensors. However, these sensors increase system cost, introduce additional hardware complexity, and may be impractical for directly measuring temperatures at critical internal locations. Virtual temperature sensors (VTSs) provide a software-based alternative by estimating component temperatures using readily available vehicle operating data.

This research presents the development and validation of a long short-term memory (LSTM) neural network-based virtual temperature sensor capable of simultaneously estimating the motor …

Analysis Of Battery Degradation Effects On Optimized Torque Splitting In Dual-Motor Electric Vehicles, Homer E. Butcher

Graduate Theses, Dissertations, and Problem Reports (ETD)

Battery electric vehicle performance depends on both powertrain efficiency and battery-health. In dual-motor all-wheel-drive battery electric vehicles, driver-requested torque can be distributed between front and rear electric drive units, creating an opportunity to reduce electrical energy demand through torque allocation. However, lithium-ion battery aging changes the electrical behavior of the energy storage system through capacity fade and internal resistance growth. Capacity fade reduces the usable energy and vehicle range, while resistance growth increases voltage drop, current-related losses, and battery electrical loading. This thesis evaluates how these degradation effects influence the energy consumption, simulated range, and battery electrical behavior of optimized …

Semantic-Weighted Lidar–Camera Slam For Robust Mapping In Vegetation-Rich Environments, David Aigbovboise Akhihiero

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many LiDAR odometry and SLAM methods are lightweight and effective, but they assume that all LiDAR point returns are equally reliable. In practice, this assumption is often violated in vegetation rich or semi transparent environments, where in a single beam footprint, LiDAR beams may intersect multiple scattering surfaces like leaves, branches or glass. These ambiguities in returns produces probabilistic or biased range measurements that violate the assumptions of most geometric registration frameworks and can lead to drift and inconsistency.

To address this challenge, this dissertation proposes a semantic-weighted LiDAR-camera SLAM framework that integrates class dependent weights into a front-end LiDAR …

Mission-Focused Multidisciplinary Design Optimization Of Tilt-Rotor Evtol Propulsion System, Tyler Critchfield, Andrew Ning

Faculty Publications

Tilt-rotor propulsion system design requires a multidisciplinary approach to tackle important challenges and competing tradeoffs between disciplines. In this paper, we model rotor aerodynamics, blade structures, vehicle drag, electric propulsion, and tonal/broadband acoustics for a tilt-rotor, electric vertical takeoff and landing aircraft using low-to-mid fidelity tools. We use gradient-based design optimization with automatic differentiation and parameter sensitivity analyses to explore the design space and complex tradeoffs of tilt-rotor distributed electric propulsion systems, exploring effects of variations in payload/empty weight, battery specific energy, and blade tip speed. This framework models multiple operating points with a mission-focused objective to account for the …

Viscoelastic Behavior Of Magnetically Filled Pdms Elastomers: Influence Of Filler Loading And Particle Type, Madison Procyk

College of Graduate Studies: Theses & Dissertations

Magnetorheological elastomers (MREs) offer a promising pathway for soft, magnetically actuated drug‑delivery systems, yet material‑selection guidelines remain unclear due to limited comparative data across particle chemistries, size scales, and concentrations. This study systematically evaluates how magnetic filler type (carbonyl iron and magnetite) and particle size (micro vs. nano), at two weight percentages – 40 wt% and 50 wt% – in Sylgard 184 PDMS influence the viscoelastic behavior of MREs intended for compliant biomedical actuation. Eight particle formulations were prepared through sieving, controlled mixing, vacuum degassing, and isotropic curing, producing nineteen total specimens (16 with filler particles and 3 without). Dynamic …

A Real-Time Autonomous Mobile Robotic System For Crack Detection And 3d Laser Profiling In Construction Using Two-Stage Deep Learning, Emmanuella Ogun

College of Graduate Studies: Theses & Dissertations

This thesis presents an autonomous mobile robotic system that integrates real-time visual crack detection with laser-based three-dimensional profiling for building inspection. The system coordinates SLAM-based navigation, deep learning perception, and manipulator-guided measurement within a unified ROS 2 framework, enabling scan-on-demand workflows where laser profiling occurs selectively at visually detected defect locations. The detection pipeline employs a two-stage architecture combining U-Net semantic segmentation with Pix2Pix residual refinement, achieving 73.9% mean intersection-over-union and 76.4% F1-score on the CrackSeg9k benchmark while maintaining 16 frames-per-second real-time throughput. Real-world validation demonstrated 95% detection success on 80 campus images under challenging conditions. The profiling subsystem utilizes …

Influence Of The Sst K-Ω Stress-Limiter Coefficient On Transonic Shock Buffet Prediction For The Oat15a Supercritical Airfoil, Melinawo Vowotor

College of Graduate Studies: Theses & Dissertations

Transonic shock buffet predictions using the Shear Stress Transport (SST) k–ω turbulence model are known to be sensitive to the stress-limiter coefficient a₁, yet no systematic investigation of this sensitivity exists. This thesis presents a parametric study of a₁ for two-dimensional URANS simulation of shock buffet on the OAT15A supercritical airfoil at M = 0.73 and Re = 3 × 10⁶. Eleven a₁ values (0.25–0.37) are examined at α = 3.5°, and a matrix of five a₁ values across five angles of attack (3.0°–3.9°) maps the interaction with incidence. The results reveal that a₁ acts as a bifurcation parameter: a …

Network-Aware Airline-Specific Flight Delay Prediction Using Tree-Based Ensemble Models, Mary Dufie Afrane

College of Graduate Studies: Theses & Dissertations

Flight delays pose persistent challenges to the efficiency and reliability of air transportation systems, affecting airlines, airports, regulators, and passengers alike. As traffic demand grows and operational environments become increasingly interconnected, accurately predicting both departure and arrival delays has become crucial for effective planning and mitigation. This study presents a network-aware, airline-specific framework for predicting flight delays in U.S. domestic air transportation systems using tree-based ensemble machine learning models. A large-scale dataset of 1.98 million flights, enriched with weather information, is used to develop predictive models for both departure and arrival delays. To capture the structural and operational complexity of …

Roadway Runoff Impacts To Trout Streams Studies For Ms4 Permit, Jobayed Hossain Badhan

College of Graduate Studies: Theses & Dissertations

Roadway runoff from Georgia Department of Transportation (GDOT) highway infrastructure poses measurable, but temporally constrained threats to cold-water trout ecosystems in northern Georgia. This study investigates temperature and dissolved oxygen (DO) dynamics in three secondary trout streams receiving GDOT roadway discharges, with the primary objective of evaluating compliance with Georgia Rule 391-3-6-.03(6)(ii),(v) under the Municipal Separate Storm Sewer System (MS4) permit framework. Field monitoring was conducted from April 2024 through October 2025 across two consecutive summer seasons using a tiered, multi-instrument approach: YSI ProDSS handheld grab sampling provided regulatory-grade reference measurements; HOBO MX-801 optical DO dataloggers recorded continuous 5-minute-interval temperature …

Effects Of Composition, Nodularity, Pouring Temperature, Inoculation, And Mold Strength On Wall-Movement In Sgi Castings During Solidification And Cooling, Noah Brack

College of Graduate Studies: Theses & Dissertations

The iron-carbon casting alloy known as spheroidal graphite iron (SGI), nodular graphite iron, or ductile iron (DI) experiences complex volume changes during its solidification and cooling as graphite nodules and austenite form. These volume changes result in forces on the mold cavity walls and can deform the mold walls in cases when mold walls lack the strength to resist the deformation. This wall movement can cause the formation of casting defects such as swell, warped part geometry, and shrinkage porosity. Though this phenomenon has been studied in the past, it remains difficult to predict casting wall movement with existing data. …

Formalizing Asymmetric Control-Telemetry Separation In Distributed Industrial Control Systems, Andrew Manison

College of Graduate Studies: Theses & Dissertations

Distributed industrial control systems often place control and telemetry traffic on the same communication substrate even though the two workloads impose different requirements. Control paths need bounded request-response latency and predictable acknowledgement semantics, whereas telemetry paths benefit from scalable publish-subscribe fanout and tolerance for consumer-side delay. This thesis argues that, for the tested class of mixed workloads on shared commodity infrastructure, these communication roles should be separated architecturally rather than forced through a single protocol. To evaluate that claim, the thesis formalizes an asymmetric control- telemetry pattern and instantiates it in the Asymtra framework using gRPC for synchronous control and …

Comprehensive Performance Evaluation Of Devops Infrastructure Under Dynamic Workloads, Abdulrazaq Mamud

College of Graduate Studies: Theses & Dissertations

This research aims to investigate performance optimization and reliability issues related to cloud-based computing environments through an analysis of three key infrastructure components: virtualized CPU resource management, distributed API rate limiting, and web server deployment architectures. This research combines machine learning and system experimentation as a way of exploring the impact of infrastructure-level behaviors on overall system performance and scalability. The first component of the research focuses on analyzing CPU Fragmentation in Virtualized Environments, where unbalanced workload allocation on Virtual CPU Cores causes increased tail latency, resulting in Service Level Agreement violations. Metrics are analyzed using the Random Forest classifier …

The Effect Of Chamber Geometry On The Performance Of Oscillating Water Column, Timilehin O. Osunade

College of Graduate Studies: Theses & Dissertations

This thesis investigates the effect of internal chamber geometry on the performance of a piezoelectric oscillating water column (OWC) wave energy harvester. Four acrylic chamber configurations with internal top-surface angles of 0°, 30°, 45°, and 60° were tested under 32 controlled conditions combining synchronous (SYN) and asynchronous (ASC) forcing at input voltages of 4, 6, 8, and 10 V. A 35 mm piezoelectric disc mounted at the chamber roof served as the power take-off element and, subject to the RC-limit caveat disclosed in Section 3.2.1, as a first-order dynamic analogue of the chamber pressure for phase-based compressibility analysis. All test …

Feasibility Of Quantifying The Dosage Of Zycotherm In Its Modified Asphalt Binders, Susmita Acharjee

College of Graduate Studies: Theses & Dissertations

The quantification of low-percentage additives in asphalt binders is challenging due to their minimal concentration and the complex composition of the binder matrix. Zycotherm, a nano-organosilane anti-stripping additive, is typically used in very small dosages (0.05%–0.20%), making its detection and quantification particularly difficult. This study investigated the feasibility of estimating Zycotherm dosage in asphalt binders by examining chemical and rheological and moisture responses. Two asphalt binder grades, PG 64-22 and PG 76-22, were modified with Zycotherm at dosages of 0.05%, 0.10%, 0.15%, and 0.20% by weight of binder, along with corresponding base binders. Laboratory experiments were conducted using Fourier Transform …

Pile Setup Effects On Driven Piles In Southeastern Coastal States, Peya Sharif

College of Graduate Studies: Theses & Dissertations

The resistance of driven piles typically increases with time after installation, a phenomenon known as pile setup. This behavior is primarily associated with the dissipation of excess porewater pressure and the progressive reconsolidation of soil surrounding the pile shaft, particularly it is observed in cohesive soils. Although several empirical and analytical models have been proposed to estimate pile setup, their practical implementation in foundation design remains limited due to uncertainties associated with soil conditions, pile geometry, resistance variability, and time dependent behavior. To address some of these uncertainties, this study collected 221 pile load test data at the End of …

The Effects Of Membrane Structure And Filtration Conditions On Virus Filtration, Wenbo Xu, Xianghong Qian, Hironobu Shirataki, Daniel Strauss, Sumith R. Wickramasinghe

Biomedical Engineering Faculty Publications and Presentations

Virus filtration is used for validation of virus clearance in the manufacture of monoclonal antibodies. Requirements for this size exclusion process include 10,000-fold reduction of virus particles and at least 95 % recovery of the monoclonal antibody in the permeate. The size difference between the rejected parvovirus particles, 25 nm, and monoclonal antibody, 10-12 nm, is about two. Membranes are designed with pore sizes around the average size of the parvovirus. Given the polydispersity in membrane pore size and virus particles, filter performance is dependent on membrane properties, feed and operating conditions. Compromised performance usually occurs due to product related …

Development Of Alternative Plasma Etching Techniques For The Selective Removal Of Tan With Respect To Sioch Dielectric Materials To Enable Future Back-End-Of-The-Line Scaling, Ivo Otto Iv

Electronic Theses & Dissertations (2024 - present)

Transistor scaling has continued according to Moore’s Law for over fifty years. As transistor size decreases, adequate power delivery is required to enable transistor scaling without performance loss. Power delivery is provided by a metal interconnect network with insulating dielectric that connects the transistor level to the power source, the signal speed within this metal line network limiting transistor level switching speeds. Reduction of signal delay has moved from primarily dimension-based improvement towards adoption of conductor and dielectric materials with lower resistivity and a reduced dielectric constant value, respectively: transitioning from Al/SiO₂ to Cu/low-κ SiOCH. With this transition comes …

6 Degrees Of Freedom Robotic Arm, Vansh Garg , ‘26, Eric Chen , ‘26, Kaw Moo , ‘26

Senior Theses, Projects, and Awards

This project involved the design, fabrication, and testing of a 6 degree of freedom robotic arm. The goal was to demonstrate that a low-cost, 3D-printed system could achieve useful strength, modularity, and basic manipulation for simple pick-and-place tasks. Potential applications include education, prototyping, hobbyist robotics, and low-precision automation.

The mechanical system uses 3D-printed arm links, cycloidal gearboxes, belt-driven transmission, bearings, and a modular end effector. These components were selected to balance cost, manufacturability, and performance, with gear reduction used to increase available joint torque. The electrical system provides motor actuation, power distribution, and controller integration, while the software enables command-based …

Solar Charging Chair, Joseph Austrian , ‘26, Jude Hemmins , ‘26, Neghemi Micah , ‘26

Senior Theses, Projects, and Awards

For our E90 project, we constructed an outdoor Adirondack-style chair with a built-in battery and solar panel, so users can charge their devices while sitting outside. Through data collection and analysis, we were able to verify that our solar energy system, consisting of a 30W panel, 96Whr battery, MPPT charge controller, and DC-AC inverter, performs better than theoretically expected. The chair was built using pressure-treated lumber with the electrical components in a weatherproof box and solar panel attached to the back rest. The total cost was $667.15.

Development Of A 3d-Printed Hemodynamic Model To Characterize Doppler Signatures Of Obstructed Tapvr, Michael R. Turner, Maher R. Saadeh, Holly D. Bauser-Heaton, Vahid Serpooshan

Summer Research Program Abstracts

No abstract provided.

Quantifying Hemodynamics In Implantable Cardiac And Renal Support Devices Using Computational Modeling, Alexander D. De Oliveira

Summer Research Program Abstracts

No abstract provided.