Engineering Commons^™

Nonequilibrium Plasma Synthesis And Processing Of Iii-Nitride Materials, Dillon Patrick Moher

McKelvey School of Engineering Graduate Student Theses & Dissertations

Nitrogen is abundant on Earth as its diatomic form, and human activity has generated a significant demand for nitrogen-containing compounds. However, its triple bond energy of 941 kJ/mol makes it a poor reactive species in the ground state. Nitrogen-containing nonequilibrium plasmas are made up of background gas, electrons, ions, and a multitude of excited states of nitrogen or even atomic nitrogen. Many of these species have rather high reactivity. As such, the plasma medium is of great potential for driving chemical reactions that involve nitrogen as a reactant, i.e., nitrogen fixation into compounds like ammonia, high-energy-density polynitrogen compounds, and metal-nitride …

Analysis Of The Impact Of Pavement Characteristics On Road Traffic Safety And Pavement Management Using Statistical Heterogeneity Models, Huiqing Lyu

USF Tampa Graduate Theses and Dissertations

Pavement shall accommodate current and predicted traffic needs in a safe, durable, and cost-effective manner. Among pavement surface characteristics, pavement friction is a critical factor contributing to roadway safety, as it directly impacts a driver's ability to execute steering, braking, and acceleration maneuvers safely. Ensuring an adequate level of pavement friction is essential to minimize the skidding risk for all road users. Continuous pavement friction measurement (CPFM) has recently become a proven approach, revolutionizing safety-related pavement management and skidding crash injury prevention. Meanwhile, pavement roughness has long been linked to vehicle fuel efficiency and pavement structural degradation. Perceptions of pavement …

Measuring Integrated Accessibility For Sustainable Mobility: A Fuzzy Set Approach Case Study, Behnam Tahmasbi, Poria Hajian, Farzaneh Tahmasbi, Qian He

School of Earth & Environment Departmental Research

Sustainable transportation is vital to climate justice and social equity. Despite the efforts to achieve sustainability, there is still a lack of adequate measurement that integrates land use and transportation systems, which can be barriers to planning implementation. With methodological improvements in fuzzy theory application, this study develops an integrated index to measure the sustainability of multimodal accessibility. We do so by defining a fuzziness degree based on the different trip purposes and modes of transportation with a case study in Isfahan, Iran. Sustainable accessibility indicators were developed for walking, biking, and public transportation to represent the performance of each …

Forensicllm: A Local Large Language Model For Digital Forensics, Binaya Sharma

LSU Master's Theses

Large Language Models (LLMs) excel in diverse natural language tasks but often lack specialization in fields like digital forensics. Their reliance on cloud-based APIs or high-performance computers restricts their use in resource-limited environments, and response hallucinations could compromise their applicability in forensic contexts. We introduce ForensicLLM, a 4-bit quantized LLaMA-3.1-8B model fine-tuned using Retrieval Augmented Fine-tuning (RAFT) on 6,739 Q&A samples extracted from 1,082 digital forensic research articles and curated digital artifacts. Evaluation on 2,244 Q&A samples showed that ForensicLLM outperformed the base LLaMA-3.1-8B model by 4.06%, 5.43%, and 15.79% on BERTScore F1, BGE-M3 cosine similarity, and G-Eval, respectively. Compared …

Measuring And Modeling Grease Degradation, Alan Gurt

LSU Doctoral Dissertations

Lubricating grease is an ideal lubricant for many devices such as roller bearings, journal bearings, slide bearings, gears, and many types of joints due to its simplicity. Once grease is put in place, it can often provide adequate lubrication for extended periods of time without the need for a complex supply system that would generally be needed for oil lubrication. However, during prolonged use, various degradation mechanisms change the physical and chemical properties of grease, possibly leading to inadequate performance and machinery failure.

In order to succinctly quantify the degradation of grease, it is essential to have robust, meaningful test …

Development Of Machine Learning-Based Tool For Prediction Of Long-Term Field Performance Of Asphalt Concrete Overlays In A Hot And Humid Climate, Elise Mansour

LSU Doctoral Dissertations

The performance of pavement plays a critical role in Maintenance, Rehabilitation and Reconstruction (MR&R) for highway agencies. Reliable and accurate estimation of pavement performance can be instrumental in prioritization of the limited resources and funding for highway agencies. The latter requires robust prediction models that can handle large-scale, real-world data and can forecast pavement performance in the long run. Unfortunately, the traditional performance prediction models have raised concerns regarding their efficiency and accuracy. It is because these models were based on a limited number of explanatory variables, were not up-to-date and were designed for forecasting short-term (up to five years) …

Mitigation Of The Environmental Impacts Of Lithium Extraction And Lithium Battery Manufacturing, Dominick R. Strollo

Sustainability Conference

Lithium extraction and the production methods utilized for lithium-ion batteries can have a large impact on the areas directly surrounding them, and if not mitigated properly, the rest of the world as well. For these batteries to be produced, lithium must be mined and refined from sources all around the world. The main concern of lithium mines is their impact on the water cycle and the surrounding water tables due to the heavy metals involved in the process and the sheer amount of water required. Production of the batteries themselves using the lithium slurry is far less impactful on the …

Automated Solutions For Hydroponic Plant Growth, Sydney Mcclure, Adam Lachguar

Sustainability Conference

Within the past year, Project H.O.M.E. has been focusing on the design and development of a semi-automatic hydroponic system specifically for sustaining plant life in Martian-like conditions. Given the significance of extended space-based travel, where the duration of human life in space is a crucial factor, growing food becomes imperative. This project has integrated electrical engineering and computer science, with features like automated pH testing and sensor-based evaluations. Key functionalities, including timed watering and automatic adjustments, were coded to enhance plant care. Initially, the project’s comprehensive research and strategic planning resulted in detailed blueprints and computer-aided design models for the …

Understanding The Plastic Issue (Poster Presentation), Regan Bossie, Peter Nguyen, John Mcswiggin, Adam Meadows

Sustainability Conference

The Plastic-Free Campus Initiative is an Embry-Riddle initiative advocating for the reduction and elimination of single-use plastics on the Daytona Beach campus.

Our poster presentation aims to highlight current issues and concerns by presenting plastic production trends, quantifying how plastic pollution has affected global ecosystems, and discussing the material characteristics of plastics and their consequences. The poster will provide an overview of the current state of global recycling and will outline key concerns that microplastics, and plastics in general, pose to public health. By presenting the current facts and concerns related to plastic and recycling, we hope to encourage individuals …

Float: A Multi-Scale Flood Loss Assessment Tool Developed From Experimentally Derived Material Damage, Anna Katya Opel

Doctoral Dissertations

Current practice of flood loss prediction presents limitations in accurately predicting building flood losses at multiple scales. While whole-building estimates can more accurately predict high-level losses (i.e., large groups of buildings), a significant analysis error is revealed with small-scale (i.e., individual, or small groups of buildings) investigation. The novel approach of collecting experimental flood data to support damage estimation has provided sufficient evidence that current damage models can and do under or overestimate loss. This research has developed a multi-scale approach to assessing flood losses based on experimentally derived material damage. The methodology is stored and accessible in a multi-scale …

Computational Design Of Complex Concentrated Alloys, Hamid Sharifi

Doctoral Dissertations

A high-throughput parameterization of modified embedded atom model (MEAM) interatomic potentials for combinations of Cu, Ti, Ni, Cr, Co, Al, Fe, and Mn was carried out using a genetic algorithm. Unary systems were parameterized based on DFT calculations and experimental results. MEAM potentials for 28 binary and 56 ternary combinations of the elements were parameterized to DFT results that were carried out with semi-automated frameworks. Specific attention was made to reproduce properties that impact compositional segregation, material strength, and mechanics. Utilizing the MEAM interatomic potentials and a Monte Carlo scheme, phase segregation in the CrNiCo, CuNiCr and CuNiCo fcc alloys …

Machine Learning-Driven Process Analysis And Optimization In Solid-State Welding And Fusion-Based Additive Manufacturing, Radif Uddin Ahmed

Master's Theses

In the modern era of advanced manufacturing, optimizing process parameters is pivotal in ensuring the quality and reliability of sophisticated component fabrication. This study presents a novel, data-driven approach to parameter optimization in two cutting-edge manufacturing techniques: Friction Stir Welding (FSW) and Laser Powder Bed Fusion (LPBF). By leveraging machine learning methodologies, this research addresses the critical challenge of efficiently determining optimal process parameters, a task traditionally relying on time-consuming and resource-intensive trial-and-error methods. This study will lead to a robust data-driven framework for process analysis of more advanced manufacturing techniques like the Additive Friction Stir Deposition (AFSD) process. Friction …

Effect Of Workload And Trust On Automation Levels In Human-Robot Collaboration, Abhiram Maddula

LSU Master's Theses

Automation is becoming increasingly common in manufacturing and assembly plants. The future lies in hybrid workspaces where the strengths of humans and robots complement each other, with robots excelling in precision, speed, and strength, and humans excelling in creativity, emotional intelligence, and complex decision-making. Collaborative robots can foster a more efficient and productive work environment by bridging the gap between human and machine capabilities. This study examines how semi-automated and automated modes impact human-robot collaboration, focusing on mental workload, trust, and task performance.

In this experiment, 58 participants performed a primary task alongside a collaborative robot assembling a miniature lamppost …

Techno-Economic Analysis Of Waste Plastic Gasification, Henrik Don-Yor Ketting

Master's Theses

The increasing generation of plastic waste and its environmental impact has driven interest in alternative disposal methods such as gasification. This study presents a techno-economic analysis of the gasification of waste plastics, specifically polypropylene (PP) and polyethylene (PE), to produce syngas. A two-stage process—thermal decomposition followed by steam reforming—was simulated using Aspen Plus. The simulation results were validated against experimental data available in the literature. The economic analysis was conducted by estimating the capital and operating costs of the gasification plant, considering factors such as feedstock costs, energy requirements, and syngas purification systems. Net Present Value Calculations were used to …

Experimental And Numerical Investigation Of Droplet Dynamics In Microscale Systems: The Influence Of Surfactants And Nanoparticles On Environmental Applications, Negin Bahadori

Master's Theses

Emulsions are suspensions of droplets dispersed into an immiscible liquid phase, with at least a water phase and an oil phase. The capability to incorporate both hydrophilic and hydrophobic components makes emulsions amenable to a variety of applications, such as bilgewater treatment and oil recovery. To optimize bilgewater treatment or oil recovery, many aspects must be considered, such as the effect of emulsion stability, the wetting conditions and, more in general, the possibility to characterize droplet’s behavior over static or dynamic conditions. This thesis investigates the roles of surfactants and nanoparticles in understanding droplet behavior in oil-water systems, with a …

Effectiveness Of Virtual Reality Training Environments, Lindsay Kristina Gouedy

Doctoral Dissertations

As technology has evolved so has training methodology in many applied fields. Training of aviation professionals is adapting by including technology features that allow for safer and less costly training methods. Pilot training is expensive given the number of flight hours and all that is included in the cost of flying an airplane. The main goal of this project is to assess the efficacy of the use of virtual reality environments as a valid training tool. Based on our literature review, we hypothesized that trainees perform simulated flight tasks more efficiently, with fewer errors, when trained using VR technology. The …

The Santa Clara, 2024-11-15, Santa Clara University

The Santa Clara

No abstract provided.

Robotic Multi-Object Grasping From A Pile: Techniques And Algorithms For Enhanced Dexterity, Tianze Chen

USF Tampa Graduate Theses and Dissertations

As robots become increasingly integrated into real-world applications such as warehousing, fulfillment centers, and manufacturing, the need for efficient and adaptable robotic systems grows. One of the key challenges is enabling robots to grasp multiple objects simultaneously, as this significantly boosts the efficiency of tasks like batch picking, sorting, and object transferring, reducing both time and energy consumption. This dissertation presents a comprehensive multi-object grasping (MOG) pipeline that includes pre-grasp selection, end-pose selection, grasping synergy calculation, and a data-driven model for estimating the number of objects being grasped. Central to this work is the development of the Experience Forest structure, …

Performance Optimization And Application Of P-Type Transparent Semiconductors In The Cdte Solar Cells, Md Zahangir Alom

USF Tampa Graduate Theses and Dissertations

CdTe thin-film solar cells are one of the major interests in the solar industry for their favorable properties. For example, CdTe has a near-ideal bandgap (1.45 eV) for absorption of the solar spectrum, and a high absorption coefficient ( ̴ 105 cm-1) and can capture 99% of light with only 2 µm of film thickness. Moreover, CdTe can be doped both n and p-type. Additionally, low production costs contribute to more affordable panel prices (0.40 $/W) [1]. The highest efficiency achieved to-date for this material is 23.1% demonstrated by First Solar, which is still lower than the theoretical limit [2]. …

Identifying Hidden Factors Influencing Soil Olsen-P In An Alkaline Calcareous Soil Using Machine Learning And Geostatistical Techniques, Moussa Bouray, Mohammed Bayad, Adnane Beniaich, Ahmed G. El-Naggar, Rebecca Muenich, Kahlil El Mejahed, Abdallah Oukarroum, Mohamed El Gharous

Biological and Agricultural Engineering Faculty Publications and Presentations

Phosphorus (P) deficiency is one of the major constraints for sustainable crop production in calcareous soils. This study aimed to elucidate the key soil characteristics modulating the variability of soil Olsen P in these typical soils. A comprehensive soil sampling initiative (1.5 samples per hectare) was conducted on a 100-ha farm, considering 31 attributes that included soil physical and chemical properties, and geographic attributes. Three machine learning algorithms—partial least squares regression (PLSR), random forest (RF), and cubist regression (CR)—were employed to understand key variables controlling soil Olsen P. Furthermore, the same data set was used to spatially map the …

Analyzing The Key Characteristics And Benefits Of Ccpr (Cold Central Plant Recycling) In Road Rehabilitation And Sustainability, Bassam Abou Yassine

Civil Engineering ETDs

Cold mix asphalt (CMA) technologies are being used in the United States and have environmental benefits. However, these technologies are not fully developed. We do not yet know their resilient and dynamic modulus, which are important for designing pavement thickness. They have not being used widely because we do not know also their performance. This study looks at three Cold Central Plant Recycling (CCPR) materials to help fill this gap. We conducted several lab tests, including the Hamburg Wheel Tracking Test (HWTT), Semi-Circular Bending Test (SCB), and Texas Overlay Test (TOT). We also tested the mechanical properties of the CCPR …

Modeling W/V-Band Satellite Communications In The Presence Of Noise Jamming, Ryan Michael Eckman

Electrical and Computer Engineering ETDs

Understanding the performance of wideband modulated signals under noise jamming conditions is important for advancing W/V-band military satellite communications. This research developed and validated models to predict performance degradation of a communication channel in the presence of wideband noise jamming. Channel models were developed that included both modulated communication signals and jammer signals. Integrated models included environmental link factors and practical implementation factors. Integrated models were verified and validated using outdoor radio frequency environments utilizing two W/V-band transceivers, a portable W-band jammer, and software defined radios. Experimental results demonstrated excellent agreement with integrated model predictions. Channel degradation due to the …

Optimizing Electric Vehicle Fleet Integration In Industrial Demand Response: Maximizing Vehicle-To-Grid Benefits While Compensating Vehicle Owners For Battery Degradation, Andre Leippi, Markus Fleschutz, Kevin Davis, Anna-Lena Klingler, Michael D. Murphy

Publications

This paper addresses the integration of electric vehicle (EV) fleets into industrial smart grids to increase operational flexibility. It focuses on an extended multi-objective optimization problem that minimizes two primary objectives: (i) the electricity expenditure of a company using its employees’ EV batteries as temporary distributed energy storage, and (ii) the costs associated with the degradation of EV batteries, given the additional usage from the company’s perspective. In this paper, the utilization of an EV fleet is simulated at the individual car level over a one-year period. These optimization problems were balanced by using real-time electricity prices and the effective …

Formation Mechanism And Strengthening Method Of Geometric-Mechanical Structure Of Plugging Zone In Deep Naturally Fractured Reservoir, Chengyuan Xu, Honglin Zhang, Jianhong Fu, Yili Kang, Zhenjiang You

Research outputs 2022 to 2026

Efficient fracture plugging plays a critical role during drilling and completion of deep naturally fractured reservoirs, minimizing fluid loss, and ensuring reservoir protection. This study investigates the formation process of the geometric-mechanical structure of fracture plugging zones through a series of experiments including microscopic visualization, photoelastic and fracture plugging experiments. By examining these experiments, we reveal the relationship between lost circulation materials (LCMs) at the micro-scale, force chain network structures at the meso-scale, and the pressure stability of plugging zones at the macro-scale. Based on the analytic hierarchy process (AHP), we introduce an evaluation index for assessing the stability of …

Surely You Can’T Be Serious: A Student’S Guide For Flight School Closure, Aidan Mcglasson, Sarah Nilsson

Publications

Flying aircraft, whether at a general aviation, commercial, or military level, is deeply engrained in American culture. Opinion polls place being a professional pilot as one of the most respected, and prestigious jobs in the country (Mushtaque, 2023). As evidenced by the popularity of movies such as Airplane!, Top Gun, or Sully, flying is something that fascinates many people. Perhaps contributing to its mystique is the difficulty and expense in obtaining the necessary training and certifications to be a pilot. Some people undergo flight training with the goal of flying commercially, as an airline or corporate pilot, while others do …

Trust-Me: Resource Allocation And Server Selection Based On Trust In Multi-Access Edge Computing, Sean Tsikteris

Electrical and Computer Engineering ETDs

Multi-access Edge Computing (MEC) is crucial for Internet of Things (IoT) applications by optimizing data processing and reducing latency. This thesis presents contributions to resource allocation and decision-making in edge computing environments. The TRUST-ME model is introduced, involving multiple edge servers and IoT devices (users) offloading computing tasks to MEC servers. A utility function is designed to assess latency and cost benefits for IoT devices using server resources. The core innovation is a novel trust model that evaluates IoT devices’ confidence in MEC servers by integrating both direct and indirect trust, based on interactions and feedback from other devices. In …

Enhancing Frp-Concrete Interface Bearing Capacity Prediction With Explainable Machine Learning: A Feature Engineering Approach And Shap Analysis, Yanping Zhu, Woubishet Zewdu Taffese, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study introduces a novel approach to predict the shear bearing capacity of FRP-concrete interfaces using explainable machine learning. Eight algorithms are employed: three standalone models (Artificial Neural Network, Support Vector Regression, and Decision Tree) and five ensemble learning models (Bagging, Random Forest, Adaptive Boosting, Gradient Boosting, and Extreme Gradient Boosting). Four scenarios with varying input features, including engineered features inspired by mechanics-based bearing capacity equations, are examined. Notably, the inclusion of engineered features such as the stiffness of the FRP strip (Kf) significantly enhanced prediction accuracy and efficiency, although the width correction coefficient (bf/bc) did not yield significant benefits, …

Antimicrobial Activity And Photostability Of Cationic Conjugated Polyelectrolytes, Mohammed Ismael Khalil

Chemical and Biological Engineering ETDs

Antimicrobial resistance is a growing global health concern, driving the need for novel

therapeutic strategies. This study explores the antimicrobial efficacy of conjugated

polyelectrolytes (CPEs) and oligo-phenylene ethynylenes (OPEs) in bacterial and viral

inactivation. Quantitative analysis revealed that light-activated CPEs and OPEs

effectively reduced bacterial viability within minutes, with significant log reductions

observed under both light and dark conditions. Additionally, the antiviral potential of a

cationic conjugated oligomer was investigated, demonstrating rapid and near-complete

inactivation of SARS-CoV-2 under visible light, both in solution and on filter materials.

Further analysis of their photophysical properties revealed that, even after

photobleaching, the compounds …

How Wildfires Threaten Water Resources: A Case Study Following The Largest Wildfire Recorded In New Mexico, Eric A. Joseph

Civil Engineering ETDs

Wildfire disturbance propagation along fluvial networks remains poorly understood. We use incident, atmospheric, and water-quality data from the largest wildfire in New Mexico’s history to quantify how this gigafire affected surface runoff processes and mobilized wildfire disturbances into fluvial networks after burning 1382 km². Surface runoff post-fire increased compared to pre-fire conditions, and precipitation events that are frequently observed in the affected watershed (<2-year recurrence) and fell during the post-fire first rainy season resulted in uncorrelated, less frequently observed runoff events (10-year recurrence). Wavelet coherence analysis highlighted that water quality disturbances propagated variably along the network, even at sites located >160 km downstream of the burn perimeter. Our findings emphasize the need to incorporate spatially resolved longitudinal sampling designs into wildfire water quality research and highlight the spatiotemporal co-dependency among atmospheric, terrestrial, aquatic processes …

Robust Data-Driven Run-To-Run Control Via One-Step Constrained Optimization For Automated Serial Sectioning, Rhianna M. Oakley

Mechanical Engineering ETDs

This Thesis develops a one-step predictive run-to-run controller (R2R-MPC) for automating a mechanical serial sectioning (MSS) system. MSS is a destructive material analysis process that iteratively removes slices of material and captures 2D images, reconstructing them into 3D representations. Commonly used in material science for characterizing materials and failure analysis, MSS typically operates in an open-loop fashion, which experiences high variability in material removal due to system disturbances. To address this, a robust closed-loop R2R-MPC is presented, modeling MSS process uncertainty using a linear differential inclusion identified from operational historical data. The R2R-MPC is posed as an optimization problem that …