Engineering Commons^™

Experimental Investigation On Mechanical Properties Of Pla Reinforced By Bamboo Fiber/Montmorillonite Clay Hybrid Composites And Analysis Of Machining Characteristics, Nirmal Kumar K

Theses and Dissertations

The study presents a comprehensive investigation into the development, characterization, and machining analysis of novel bio-based polymer hybrid composites comprising Polylactic acid (PLA), bamboo powders (BP), and montmorillonite clay particles (MMT). Initially, the hybrid composites were fabricated using a solvent-free stir casting process, optimizing the weight percentages of BP and MMT to enhance mechanical and thermal properties.

Mechanical tests, including tensile, flexural, and impact tests, along with thermal analysis using thermogravimetric analysis and differential scanning calorimetry, were conducted to evaluate the performance of the composites. In the subsequent phases, advanced machining techniques were employed to analyze the machining characteristics of …

Optical Responses Of Hybrid Electromagnetic Nanostructures, Dominic Bosomtwi

Optical Science and Engineering ETDs

Fano resonances result from the interference between a broad background and a narrow state, producing asymmetric scattering profiles. Under specific conditions, destructive interference collapses the Fano resonance width, leading to bound states in the continuum (BICs) that localize light within a nanostructure while maintaining an infinitely high-quality factor (Q-factor).

This dissertation explores the design of nanostructures with multilayer hybrid plasmonic-dielectric metasurfaces using full-wave numerical simulations, facilitating multiple Fano resonances and BICs. By adjusting nanoantenna dimensions, multiple modes are excited at plasmonic-dielectric interfaces, leading to strong interactions and hybridization of energy levels, manifested as Rabi splitting.

These findings enable advancements in …

Development Of Multivariate-Coupled Grouting Diffusion Model For Rcc, Xiao Sun, Yao Wang, Hengrui Liu, Zhuanjia Yang, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Grouting Quality of Grout-Enriched Roller Compacted Concrete (RCC) is Difficult to Be Quantified Due to the Fact that the Crucial Effects, Such as Infiltration and the Compaction of the Skeleton of the RCC, Are Not Taken into Consideration. Combined with Model Testing, This Study Proposes an Improved Grouting Prediction Model Which Considers the Coupling Effect of Pore Fractal Properties, Time Variation of Grout Rheological Properties and Infiltration. Moreover, the Influence of Construction Parameters Such as Grouting Parameters, Construction Period Selection, Grouting Pipe Arrangement on the Grouting Effect Was Clarified. the Tests Indicated that the Maximum Diffusion Range of Slurry …

Medial Patellofemoral Ligament Augmented With A Reinforced Bioinductive Implant Is Biomechanically Similar To The Native Medial Patellofemoral Ligament At Time Zero In A Cadaveric Model, Sean Mcmillan, Seth Sherman, Zachary Brown, Erik Brewer, Elizabeth Ford

Rowan-Virtua School of Translational Biomedical Engineering & Sciences Departmental Research

Purpose: To biomechanically compare primary medial patellofemoral ligament (MPFL) repair (MPFLr) augmented with a reinforced bioinductive implant (RBI) to the native MPFL ligament and a semitendinosus (semi-T) MPFL reconstruction (MPFLR) at time zero. Methods: Four fresh-frozen matched pair cadavers (8 knees) were used to biomechanically compare the native MPFL to augmented MPFLr (n = 4) and semi-T MPFLR (n = 4). The native MPFL (n = 8) was isolated, preserving the femoral and patellar attachments, and pulled to failure. The semi-T was harvested from 1 of the matched pairs and whipstitched, as was a 250-mm × 5-mm RBI. A standard …

Factors Influencing Bridge Inspection In Developing Countries, Challenges And Future Directions: A Systematic Literature Review, Tuba Arshad, Dr. Rully Andhika Karim, Ayomi Dita Rarasati

Smart City

Bridges are very important to promote economic growth, mitigate poverty, and address persistent environmental issues. With the construction of new bridges, it is crucial to have an effective bridge inspection procedure. But most developing countries are still struggling in this field. This review examines common factors affecting bridge inspection in developing countries and their impact on bridge condition and performance while exploring strategies to improve those factors in developing countries in a systematic review. A total of 172 articles were identified through an explorative search of Direct Scopus, Google Scholar, and hand-search with limitations of the years 2013 to 2024. …

Space Program: Center For Space Research - Austin, Texas #1, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Professor Bob Twiggs titled "Space Program: Center for Space Research - Austin, Texas" from July 12, 2024.

Chemical And Physical Properties Of Fine Fractions From A Village Proximate To A Uranium Mine: Insights About Soil Health, Mary P. Haley

Nanoscience and Microsystems ETDs

Thousands of abandoned uranium mines (AUM) in Native American tribal lands have not been fully remediated, leaving uranium mine wastes exposed and accessible for potential erosion and transport by wind. Analyzing the metal and organic content of the fine-grained fractions in soils could uncover the impact of mine legacy on the soil health in communities that live in proximity to AUM. This study investigates the physical and chemical properties of the fine-grained fraction (μm) of soils to quantify the effect of heavy metal-bearing particulates on the soil health in the village of Paguate and within the Jackpile-Paguate AUM located on …

Membrane Hinges For Deployable Systems, C. Mitchel Skinner

Theses and Dissertations

Origami-inspired and deployable technology has become increasingly common in a variety of applications including satellite and antenna designs for space applications. The drive to utilize ultra-thin materials in the design of these deployable space structures has led to the development of membrane hinges. Membrane hinges show promise as an effective surrogate fold because of their potential advantages including requiring minimal volume and mass, allowing for small bending radii, and functioning without lubricant. Two challenges associated with membrane hinges include reliability after repeated cyclic loading and predictability of a large deployable with radially-unconstrained membrane hinges. The research presented includes the cyclic …

Fem-Based Conductive Heat Transfer Analytical Description Of Solidification Rate And Temperature Gradient During Lateral Laser Beam Oscillation Welding Of Aluminum Alloy, Jason Cheon, Cheolhee Kim, Sanghoon Kang, Minjung Kang

Mechanical and Materials Engineering Faculty Publications and Presentations

This study investigates the feasibility of utilizing the finite element method (FEM)-based conductive heat transfer (CHT) analysis simulation to determine temperature gradients and solidification rates at the solid–liquid interface during laser beam oscillation welding. By comparing experimental observations with FEM-based CHT analysis, the underlying microstructural evolution and grain formation during welding were examined. FEM-based CHT enables the calculation of temperature gradients (G) and solidification rates (R), offering insights into the formation of equiaxed structures, which are crucial for suppressing hot cracking. Columnar-to-equiaxed structure transition thresholds, such as G/R and G³/R, accurately predict …

Gene Expression Analysis Reveals Dysregulation In Traumatic Brain Injury Leading To Tauopathy, Kristina M. Tosi

USF Tampa Graduate Theses and Dissertations

Traumatic Brain Injury (TBI) causes a cascade of detrimental events within neurons, contributing to a host of neurological diseases relating to dementia. In this study we have performed a meta-analysis comparing differentially expressed genes (DEG) in specific cell types such as neurons and microglia revealing inflammation as a common driver of neurological deficiencies post TBI. Inflammation and hypoxia are well characterized features of TBI; however, the molecular mechanisms causing tau hyperphosphorylation by tauopathy associated genes (TAG) post-TBI are currently poorly understood. Furthermore, there are limited in-vitro neuroinflammatory models that mimic primary and secondary TBI. We hypothesize that inducing hypoxia and …

Performance Assessment Of Aboveground Storage Tanks During Flood Events, Md Manik Mia

LSU Doctoral Dissertations

This research addressed the performance of aboveground storage tanks (ASTs) and connected pipelines during floods. ASTs, integral to the oil and gas industry, store hazardous materials like crude oil and chemicals. Positioned near coastal regions, especially the hurricane-prone Gulf Coast, these areas are vulnerable to natural hazards such as floods and hurricanes. This vulnerability can lead to potential environmental and economic disasters, as seen with past hurricanes.
The primary objectives were to investigate AST bottom plate failure mechanisms under flood conditions, assess material failure in tank shells and bottom plates using finite element models, examine the behavior of connected pipelines, …

Vysion Software, Isaias Hernandez-Dominguez Jr, Chander Luderman Miller

2024 Symposium

Vision loss presents significant challenges in daily life. Existing solutions for blind and visually impaired individuals are often limited in functionality, expensive, or complex to use. Vysion Software addresses this gap by developing a user-friendly, all-in-one AI companion app that provides features including text summarization, real-time audio descriptions, and AI-enhanced navigation. This project details the development plan, initial functionalities, and future vision for Vysion Software.

Slimsat, Robert J. Twiggs, Nick Pugh

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs and Nick Pugh titled "SlimSat" from July 11, 2024.

Biocompatibility Of Mussel-Inspired Water-Soluble Tissue Adhesives, Aishwarya V. Menon, Amelia A. Putnam-Neep, Caitlin E. Brown, Christa J. Crain, Gert Breur, Sanjeev K. Narayanan, Jonathan Wilker, Julie C. Liu

School of Chemical Engineering Faculty Publications

Wound closure in surgeries is traditionally achieved using invasive methods such as sutures and staples. Adhesion-based wound closure methods such as tissue adhesives, sealants, and hemostats are slowly replacing these methods due to their ease of application. Although several chemistries have been developed and used commercially for wound closure, there is still a need for better tissue adhesives from the point of view of toxicity, wet-adhesion strength, and long-term bonding. Catechol chemistry has shown great promise in developing wet-set adhesives that meet these criteria. Herein, we have studied the biocompatibility of a catechol-based copolymer adhesive, poly([dopamine methacrylamide]-co-[methyl methacrylate]-co-[poly(ethylene glycol) methyl …

Development And Characterization Of Automated Screen Mesh-Based Microfluidic Device To Perform Continuous Countercurrent Liquid-Liquid Extraction, Quinn Mcculloch

Nanoscience and Microsystems ETDs

Continuous Countercurrent Microfluidic Liquid-Liquid Extraction (CC-MLLE) shows tremendous potential to generate large numbers of equilibrium stages of separation in a small footprint, with a minimum of pumping, valving, and phase separation steps. However, CC-MLLE rarely appears in literature because it requires a delicate balance between capillary and hydrodynamic forces for deterministic flow.

This dissertation showcases a patented screen mesh-based CC-MLLE invention that performs stable, long-duration (> 36 hr.), countercurrent liquid-liquid extraction and achieves 37 equilibrium stages within a 38.5 μl internal volume. The device is fabricated from chemically resistant polyetheretherketone plastic, using standard machine shop equipment, a plotting cutter, screen …

The Newgeneratortm Decentralized Wastewater Treatment System For Non-Sewered Sanitation: Technology Advancement Through Field Evaluation And Modeling, Hsiang-Yang Shyu

USF Tampa Graduate Theses and Dissertations

Non-sewered sanitation systems (NSSS) offer innovative solutions to sanitation challenges in areas lacking basic facilities, utilizing advanced treatment technologies for on-site water reuse. The NEWgenerator (NG), an advanced NSSS developed at the University of South Florida under the Bill & Melinda Gates Foundation’s Reinventing the Toilet Challenge, integrates an anaerobic membrane bioreactor (AnMBR), an ion exchange-based nutrient capture system (NCS), and an electrochlorinator for final disinfection. This study builds on previous field trials of the NG system, focusing on developing, evaluating, and optimizing its water reuse capabilities through field trials, system dynamics modeling, and advanced monitoring techniques.

In the first …

Hurricane Vulnerability Of Above Ground Storage Tanks, Santosh Ghimire

LSU Master's Theses

The objectives of this research were to: 1) develop an approach to determine the effectiveness of regional storm surge reduction strategies and structural mitigation measures for aboveground storage tanks (ASTs), and 2) study the feasibility of controlled flotation of ASTs during flood and storm surge events. This study provided a comprehensive risk assessment strategy for regional portfolio of tanks, considering all dominant failure modes relevant to future planning initiatives aimed at reducing AST failures. Additionally, this research contributed a new methodology to prevent AST failures during flooding, offering a potential solution to prevent hazardous spills.

Design guidelines such as API …

Embedding Direction Of Arrival And Antenna Beamforming Algorithms On Automated Software Defined Radio Platforms, Adrian J. Lewis

Electrical and Computer Engineering ETDs

Antenna arrays are an essential technology in the modern era in both communications and radar applications. The algorithms used for antenna arrays are beginning to be embedded in smart device applications to enable greater communication abilities. This thesis explores the idea of embedding direction of arrival and beamforming algorithms using a software defined radio platform. Specifically, the Multiple Signal Classification (MuSiC) algorithm and Minimum Variance Distortionless Response (MVDR) algorithm are combined. The combination of similar algorithms has the potential to be used in many internet of things applications to enable more dynamic communication ability.

Book Review: Credible: The Power Of Expert Leaders, Carl L. Tolbert

The Journal of Values-Based Leadership

Amanda Goodall’s (2023) book Credible: The Power of Expert Leaders argues why expert leaders are needed more now than ever across all organizational domains. Goodall describes the book as a chronicle of the “natural experiment” showcasing failures of nonexperts leading various sized groups and organizations, also citing parallel success by expert leaders (p. 1). The book is divided into eight chapters, starting with the introduction and examining the need for experts, the recruitment and development of experts, and finally, the organizational environment to sustain experts. The introduction begins as a corollary to Nichols’ (2024) work regarding how society no longer …

Vacuum Assisted Resin Transfer Method, Henry Allen

2024 Symposium

The vacuum assisted resin transfer method (VARTM) is a process used to make composite materials. This process is done using a mold or plate as a base and then building up the rest of the set up from there. On the base is the vacuum seal tape, spiral or percolated tubing, a connector for the tubing, the fiber plies in the center, separation layer, vacuum mesh, and the vacuum bag layer. This setup is then connected to the resin container. The other end is connected to a catch pot and vacuum pump. The purpose of the VARTM guided study was …

Adaptive Screen Capture Video Analysis, Ugesh Egala

Electrical and Computer Engineering ETDs

This thesis presents a system for analyzing student activities during class sessions to gain insights into the learning process. A dataset consisting of 14 screen recordings, with 2 videos labeled across two stages, was used for training, validation, and testing. The methodology employs adaptive sampling, initially at 10 frames per minute to identify active regions, followed by detailed analysis at 1 frame per second using OCR to detect typing activities through character changes. The results demonstrate over a 50% reduction in computational load while maintaining high accuracy in detecting student engagement. A total of 26 hours of screen capture videos …

Bio-Inspired Robotic Framework For Spatiotemporal Analyses In Environmental Monitoring Applications, Maliha Kabir

Electrical Engineering Theses

Frequent fluctuations in the environment's temperature and climate significantly impact our crop fields. Floods and droughts occur in different places in different seasons, which is very unusual and affects the crops' health and productivity. During these calamities, they are also not able to monitor their crop fields. However, if it is possible by providing farmers with information about their fields' conditions like temperature, pressure, and soil moisture, we can help them assess environmental conditions for specific areas. This data can also aid farmers in determining the appropriate amounts of fertilizers and pesticides to apply to their crops and which crops …

The Growth Of Ethanol In Brazil: Sugarcane, Corn, And A Few Other Things, Fabio Mattos

Cornhusker Economics

Although we can expect more ethanol produced from corn in the coming years, it is unclear whether it will keep expanding at the same pace as in recent years or how much it will contribute to total ethanol production.

One point to keep an eye on is the typical dynamics of markets. If supply and demand conditions and price movements make corn-ethanol more profitable, ethanol plants in Brazil will keep increasing their production. If it makes more economic sense to produce corn-ethanol (as it happened recently), they will use more corn to produce ethanol.

Supply and demand conditions for ethanol, …

Geospatial Analysis Of Hydrologic Nitrogen In Ohio Using Terrain Ruggedness Index (Tri) And Terrain Position Index (Tpi), Shreyas N. Rajagopalan, Olatunde D. Akanbi, Vibha S. Mandayam, Erika I. Barcelos, Roger H. French

Student Scholarship

Hydrologic nitrogen in ecosystems can significantly impact water quality. Excessive nitrogen, often originating from agricultural runoff, wastewater discharge, and industrial activities, can lead to eutrophication – the over-enrichment of water bodies with nutrients, resulting in excessive algal growth and depleted oxygen levels. This study aims to use geospatial analytics to identify areas in Ohio that are more susceptible to high nitrogen levels due to their topographic characteristics.

Terrain Ruggedness Index (TRI) and Terrain Position Index (TPI) are two key metrics derived from Digital Elevation Models (DEMs) that can help characterize the landscape. TRI measures the variability in elevation of adjacent …

Fairification Of Geospatial Data, Attiksh Ansool Panda, Olatunde D. Akanbi, Vibha S. Mandayam, Erika I. Barcelos, Roger H. French

Student Scholarship

FAIRification (Findability, Accessibility, Interoperability, and Reusability) of geospatial and temporal data from the United States Geological Survey (USGS) is crucial for the continuance of the National Science Foundation (NSF) Engineering Research Center for Advancing Sustainable and Distributed Fertilizer Production (CASFER) whose aim is to aid in the development of eco-friendly fertilizers. The USGS data contains key information about water quality and contaminants, which are important metrics for our geospatial project since our work aims to track the contaminants' flow and work towards their reduction and subsequent elimination. FAIR principles refer to - Findability, Accessibility, Interoperability, and Reusability. This is important …

Geospatial And How It's Used By Casfer, Eduardo A. Castillo, Olatunde D. Akanbi, Vibha S. Mandayam, Erika I. Barcelos, Roger H. French

Student Scholarship

Project CASFER has a goal to develop the next generation of decarbonized nitrogen based fertilizer. They want to do this by

• Capturing nitrogen from waste, recycling the nitrogen, then producing and distributing CASFER fertilizers to farmers. 

CASFER is made up of 5 different universities that all work together to make up CASFER, Texas Tech University, Case Western University, FAMU, Georgia tech, and MIT.

Development And Operationalizing Of The Learning Experience Design Process To Create Integrated Stem Interventions, Vanessa Begat

LSU Doctoral Dissertations

Globally, the demand for people prepared to enter Science, Technology, Engineering and Math (STEM) careers is increasing. To help fill this demand, many formal and informal STEM educational interventions have been implemented in the K-12 domain. However, due to the lack of a clearly defined framework for documenting the nature and scope of the intervention (National Research Council, 2014), the interventions vary greatly in their success, sustainability, and replicability. This research is grounded in Educational Design Research and uses the principle of Learning Experience Design (LXD) to develop a framework for thoughtfully designing and documenting a STEM intervention. This framework …

Experimentally Verified Effective Doping Model For Lactate And Troponin Ofet Biosensors Using Machine Learning Algorithm, Sameh O. Abdellatif, Hana Masalam, Salma Ahmed

Electrical Engineering

No abstract provided.

Experimental Validation Of An Analytical Transient Model For Saturated Boosting Gain In Dc–Dc Converters With Variable Duty Cycle, Goliana Samir, Simon Ezzat, Wagdy Anis, Sameh O. Abdellatif

Electrical Engineering

No abstract provided.

Low-Power Dc-Dc Converters For Smart And Environmentally-Friendly Electric Vehicles: Design, Simulation, And Fabrication On A Glass Substrate, Michelle Makar, Sameh O. Abdellatif

Electrical Engineering

No abstract provided.