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Full-Text Articles in Engineering

Kinetics, Thermodynamics, And Biological Characterizations Of Hydrolysates Enzymatically Produced From Proteins Extracted From Microalgae, Hebah Al-Amodi Nov 2024

Kinetics, Thermodynamics, And Biological Characterizations Of Hydrolysates Enzymatically Produced From Proteins Extracted From Microalgae, Hebah Al-Amodi

Theses

This thesis aims to explore the use of Zeolitic Imidazolate Framework-L (ZIF-L) as a support for immobilizing alcalase and its potency in producing protein hydrolysates. ZIF-L was synthesized at room temperature using an aqueous solution, and alcalase was immobilized through adsorption batch experiment. The successful immobilization of alcalase on ZIF-L was confirmed through Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The maximum adsorption capacity of alcalase on ZIF-L was determined to be 672.1 ± 5.5 mg g-1 at 40°C using an initial protein concentration of 5 mg mL-1. Adsorption equilibrium data …


3d Printed Microfluidic Fabrication Methodology, Characterization, Mechanical Design, And Applications In Electrostatic Artificial Muscles And Benthic Microbial Fuel Cells, Terak B. Hornik Nov 2024

3d Printed Microfluidic Fabrication Methodology, Characterization, Mechanical Design, And Applications In Electrostatic Artificial Muscles And Benthic Microbial Fuel Cells, Terak B. Hornik

Master's Theses

The fabrication of microfluidic devices often requires specialized methods. The development of these methods requires careful characterization and understanding of the processes involved. Using primarily PolyJet 3D printing technology, microfluidics offers a wide scope of applications such as microfluidic benthic microbial fuel cells (MBMFCs) and electrostatic artificial muscles. MBMFCs benefit from the confinement of the microbes resulting in close proximity between the electrode and the organisms. Using a modular design called the Sponge, assembly and upscaling is possible. Electrostatic artificial muscles benefit from a microfluidic approach due to the non-linearity of electrostatic attraction creating disproportionate benefits when miniaturized. When designed …


Deciphering Rodent Behavior: Unraveling Complex Decision-Making Through High-Throughput Data Analysis In Behavioral Neuroscience, Atanu Giri Nov 2024

Deciphering Rodent Behavior: Unraveling Complex Decision-Making Through High-Throughput Data Analysis In Behavioral Neuroscience, Atanu Giri

Open Access Theses & Dissertations

Understanding the effects of substance use on decision-making is critical for both clinical andtranslational research. In this thesis, I present two complementary studies that explore decision- making behavior in rodents with a focus on alcohol consumption and novel experimental frame- works. The first study examines the impact of acute alcohol consumption on decision-making in a behavioral approach-avoidance task. Rats were presented with a concurrent choice of consuming alcohol and sucrose mixtures across four distinct concentrations, allowing for the analysis of ap- proach or avoidance behavior. Sex-dependent differences emerged, with male rats demonstrating a significantly higher tendency to approach higher alcohol …


Smuggling Of Person By Sea In Southeast Asia : From Regional Perspective, Sovisal Srey Nov 2024

Smuggling Of Person By Sea In Southeast Asia : From Regional Perspective, Sovisal Srey

World Maritime University Dissertations

No abstract provided.


Enhancement Of Search And Rescue Within The Coastal Waters Of Sierra Leone, Mohamed Osman Kamara Nov 2024

Enhancement Of Search And Rescue Within The Coastal Waters Of Sierra Leone, Mohamed Osman Kamara

World Maritime University Dissertations

No abstract provided.


Precision Bottlebrush Polymers: Synthesis, Characterization, And Structure-Property Relationship, Nduka D. Ogbonna Nov 2024

Precision Bottlebrush Polymers: Synthesis, Characterization, And Structure-Property Relationship, Nduka D. Ogbonna

LSU Doctoral Dissertations

Bottlebrush polymers, a type of non-linear polymer characterized by densely grafted side chains on a linear backbone, offer a versatile platform for material design due to their unique thermomechanical and rheological behavior. Addressing the grand challenge of achieving structural precision for bottlebrush polymers remains crucial because traditional disperse mixtures are plagued with batch variability, limiting our ability to control their functions, and correlate theoretical predictions with experiments. To date, narrow-dispersity bottlebrush polymers remain highly heterogeneous, as they are typically synthesized from disperse linear building blocks.

To address this longstanding challenge of structural heterogeneity in brush polymers, the primary objective of …


Development Of Multifunctional Wood Composites With Integrated Phase Change Materials For Enhanced Thermal Management, Self-Healing, And Sustainability., Emmanuel Igbokwe Nov 2024

Development Of Multifunctional Wood Composites With Integrated Phase Change Materials For Enhanced Thermal Management, Self-Healing, And Sustainability., Emmanuel Igbokwe

LSU Master's Theses

Abstract

This study focused on incorporating self-healing, flame retardancy, and energy harvesting capabilities into the wood composite to contribute to more sustainable and energy-efficient building practices. Oriented strand board has been widely used as sheath for roofing or dry walls in residential buildings. Residential buildings account for a large portion of energy consumption. Therefore, an oriented strand board with energy harvesting capability is highly desired. Additionally, flame retardancy and damage self-healing and end-of-life recycling are also critical features for buildings.

In this study, we prepared a novel oriented strand board by constructing sandwich structures. The face sheets of the sandwich …


Resource Harvesting For Parallel Functions In Serverless Workflows, Peiman Fotouhi Oct 2024

Resource Harvesting For Parallel Functions In Serverless Workflows, Peiman Fotouhi

LSU Master's Theses

In the rapidly evolving landscape of cloud computing, serverless architectures have gained attention for their scalability and cost-effectiveness. This thesis aims to introduce a novel approach to maximize resource utilization in serverless environments through the concept of harvesting idle resources within Directed Acyclic Graph (DAG)-based workloads. Our proposed solution targets resource harvesting at parallel stages by utilizing Machine Learning models to accurately harvest or accelerate serverless functions. Additionally, we present a scheduling algorithm specifically designed to address the unique requirements of DAG workloads in cloud environments.

The framework leverages dynamic resource allocation techniques to identify and exploit idle resources within …


Performance Analysis Of C++ Parallel Algorithms In Hpx, Srinivas Yadav Singanaboina Oct 2024

Performance Analysis Of C++ Parallel Algorithms In Hpx, Srinivas Yadav Singanaboina

LSU Master's Theses

The exponential growth in computational power and the increasing demand for high-performance applications have driven the need for greater parallel efficiency. Over the years, the number of cores in consumer-level CPUs and high-performance computing (HPC) systems has grown significantly. In response, numerous parallel programming li- braries have been developed. Each of these libraries offers unique mechanisms to enhance parallel performance. In this paper, we investigate the performance of five such paral- lel programming backends: C++ std::execution::par, OpenMP, TBB, Taskflow, and HPX. We evaluate these libraries using two sets of benchmarks. The first set focuses on standard C++ STL algorithms, including …


Impacts Of Phosphate And Residual Free Chlorine On The Precipitation, Stability And Dissolution Of Lead Corrosion Products, Yao Ma Oct 2024

Impacts Of Phosphate And Residual Free Chlorine On The Precipitation, Stability And Dissolution Of Lead Corrosion Products, Yao Ma

McKelvey School of Engineering Graduate Student Theses & Dissertations

Lead release from lead pipes into drinking water is a critical threat to public health. Orthophosphate addition is an established method of controlling lead concentrations in tap water. Many phosphate-based inhibitors currently used by utilities are blends of orthophosphate and polyphosphate. Orthophosphate can limit lead release from pipes by forming low-solubility lead phosphate solids on pipe inner surfaces. In contrast, polyphosphate can accelerate lead release by forming soluble lead-phosphate complexes. Due to the potential conversion from polyphosphate to orthophosphate in the distribution system and to complex dynamics of water chemistry in lead service lines (LSLs), the net impact of a …


Biodegradable And Green Controlled Release Formulations For Fertilizers, Srivalli Sriperambudur Oct 2024

Biodegradable And Green Controlled Release Formulations For Fertilizers, Srivalli Sriperambudur

USF Tampa Graduate Theses and Dissertations

This study aims to address environmental concerns associated with conventional fertilizers, and the persistence of synthetic polymers in soils and investigates the use of biodegradable cellulose esters as sustainable coatings for controlled-release fertilizers (CRFs). The focus is mainly on the synthesis of biodegradable cellulose esters as sustainable coatings for CRFs and applied as a coating on urea fertilizer prills to control nutrient release. The synthesized biodegradable coatings aim to provide effective nutrient delivery over time while minimizing environmental impact. Cellulose esters were synthesized using both saturated and unsaturated fatty acids, followed by crosslinking using thiols. Characterization techniques like FTIR, DSC, …


Evaluating Laser Tracking For The Improvement Of Quality Control Methods Of Precast Concrete, Blake A. Barbay Oct 2024

Evaluating Laser Tracking For The Improvement Of Quality Control Methods Of Precast Concrete, Blake A. Barbay

LSU Master's Theses

Current quality control (QC) methods of precast concrete are outdated and present challenges of human error and lengthy inspections. Current research into modernizing QC practices revolves around the implementation of laser scanners, with less focus on the possibility of using laser trackers. The aim of this study is to evaluate the implementation of laser trackers into the QC process of precast concrete by comparing time, accuracy, and cost to the traditional method of using a tape measure. The time studies and accuracy tests were performed in the pre- and post-pour of the precast concrete process at a precast concrete plant …


Vulnerability Discovery On Broadcom Devices With Qemu, Christian Shane Douglas Little Oct 2024

Vulnerability Discovery On Broadcom Devices With Qemu, Christian Shane Douglas Little

USF Tampa Graduate Theses and Dissertations

System-on-chip (SoC) devices in the form of routers, access points, and smart appliances have become an increasingly prevalent aspect of our infrastructure. Performing vulnerability research on these devices may be exceptionally difficult given the on-hardware limitations, inability to guarantee certain aspects of the system, and lack of information when the appliance’s source code is not available.In this thesis, we present Broadfeather, a QEMU-based emulation target, and framework for dynamic analysis and instrumentation. While Broadfeather supports data types shared across many chips under the Broadcom umbrella, it is primarily geared towards the BCM6755 Wi-Fi 6E capable chipset. Broadfeather also features the …


An In-Situ Method For Quantifying Entropy Generation In Fatigue Via A Novel Thermographic Approach, Peyton J. Wilson Oct 2024

An In-Situ Method For Quantifying Entropy Generation In Fatigue Via A Novel Thermographic Approach, Peyton J. Wilson

LSU Master's Theses

This work features a new approach that is used to measure the rate of plastic work during a cyclic fatigue test, based on the first and second laws of thermodynamics. Using the one-dimensional Fourier heat equation coupled with the concept of fracture fatigue entropy, the rate of plastic work during fatigue can be measured without the need to interrupt a fatigue test, and the accumulated entropy to failure can be quantified. Experimental fatigue tests are conducted on Aluminum 6061-T6 specimens under cyclic axial loading and Carbon Steel 1018 specimens under fully reversed cyclic bending loading. The obtained results in addition …


Automation, Improvement, And Sensitivity Analysis Of 3d Parameterized Maize Stalk Models, Joseph Steven Carter Oct 2024

Automation, Improvement, And Sensitivity Analysis Of 3d Parameterized Maize Stalk Models, Joseph Steven Carter

Theses and Dissertations

Maize is the most grown crop in the world. Each year, 5% of maize is lost due to a phenomenon known as stalk lodging (breakage of the stalk below the ear). One of the most promising solutions to stalk lodging is to design stalks with superior geometry to increase stalk strength. Researchers have developed a 3D parameterized maize stalk model, but these models take a long time to structurally analyze and are missing important material properties. This thesis addressed these problems by developing an automated package for analyzing the 3D parameterized maize stalk model, and by measuring the longitudinal shear …


Multiscale & Multiphysics Model Of Damage In Lithium-Ion Batteries, Edris Akbari Oct 2024

Multiscale & Multiphysics Model Of Damage In Lithium-Ion Batteries, Edris Akbari

LSU Doctoral Dissertations

The demand for safer and more reliable lithium-ion batteries (LIBs) in electric vehicles has increased significantly, especially in addressing mechanical failures like internal short circuits (ISCs), which can lead to thermal runaway. This research investigates the mechanical behavior and damage mechanisms in lithium-ion pouch cells through a multiscale and multiphysics approach, focusing on Lithium Nickel Manganese Cobalt Oxide (NMC) and Lithium Iron Phosphate (LFP) batteries.

The study involved quasi-static and dynamic mechanical tests, including indentation and high-speed penetration, to evaluate stress-strain responses and fracture behaviors. Anisotropic mechanical properties were measured for individual battery components (anode, cathode, separator, and shell) using …


Design Of End Bent Piles For Downdrag, Tanna Frye Oct 2024

Design Of End Bent Piles For Downdrag, Tanna Frye

USF Tampa Graduate Theses and Dissertations

Embankments are commonly used for bridge approaches, with mechanically stabilized earth (MSE) walls being the preferred choice in Florida. However, the construction of embankments leads to the settlement of the underlying soil, regardless of soil type. When piles are driven before embankment construction, the initial settlement of the original soil creates relative movement between the pile and the surrounding soil, introducing frictional forces. When the existing soils move downward relative to the pile, a downward-oriented side shear known as downdrag is introduced. While downdrag is addressed in current codes and textbooks, it is often only briefly mentioned and primarily in …


Integrating Risk And Vulnerability: Exploring A Unified Model For Supply Chain Resiliency, William G. Cook Oct 2024

Integrating Risk And Vulnerability: Exploring A Unified Model For Supply Chain Resiliency, William G. Cook

USF Tampa Graduate Theses and Dissertations

The world has entered an era of retreating globalization, mounting geo-political tensions, rising protectionism, and increasing focus on the fragility of complex supply chains. The negative impacts of supply chain disruptions have been increasingly documented since the turn of the century. Given the global scale of recent disruptions, supply chain resiliency has become a national imperative. The Global Financial Crisis, the Covid-19 pandemic, and other major disruptive events demonstrate the active role of government in mitigating damage, the enduring effects of regulation, and the resultant re-evaluation of supply chain strategies by the private and public sectors. In this environment, supply …


Synthesis Of Neuronal Network Dynamics For Optimal Stimulus Encoding And Retention, Bethanna Thompson Oct 2024

Synthesis Of Neuronal Network Dynamics For Optimal Stimulus Encoding And Retention, Bethanna Thompson

McKelvey School of Engineering Graduate Student Theses & Dissertations

A central goal in neuroscience is to understand the relationship between the structure and activity of the brain and the resulting experience of thought and behavior that the brain underpins. Within this goal is the specific study of working memory: the process of storing, managing, and integrating incoming sensory information in the context of ongoing tasks. The process of working memory is foundational to higher cognition and reasoning, determining how we comprehend and interact with the world around us. The neural circuits responsible for working memory are seemingly able to store and process afferent stimuli with other recent or relevant …


Actuation And Stabilization Of Volume-Efficient Origami-Inspired Mechanisms, Hunter T. Pruett Oct 2024

Actuation And Stabilization Of Volume-Efficient Origami-Inspired Mechanisms, Hunter T. Pruett

Theses and Dissertations

Trends in the aerospace industry are driving payloads to be smaller and less expensive while yet delivering comparatively large antennas. Deployable reflectarray antennas (RA) are the object of much research to meet these demands because they operate in a flat plane and are easier to stow than parabolic reflector antennas. Because they operate in flat plane, deployable RAs are well-suited to thickness-accommodated origami-inspired mechanisms. This work addresses pattern selection and modification, thickness accommodation, actuation, and stabilization of origami-inspired mechanisms intended to be used as RAs. First, a modified Miura-ori pattern termed volume-efficient Miura-ori (VEMO) is introduced, selected for its ability …


Advancing Data-Driven Disaster Debris Characterization And Quantification, Jasmine Bekkaye Oct 2024

Advancing Data-Driven Disaster Debris Characterization And Quantification, Jasmine Bekkaye

LSU Doctoral Dissertations

Natural hazards generate tremendous amounts of debris that negatively impact communities and overwhelm waste management infrastructure. The challenge in disaster debris planning and management stems from inconsistent and scarce post-disaster debris quantity data due to the chaotic nature of recovery operations. This leads to a limited understanding of key factors influencing disaster debris generation across hazards and regions, hindering the accuracy and efficiency of modeling. With the increasing availability of comprehensive post-disaster waste datasets, the capacity to understand debris generation is expanding. This dissertation aims to fill knowledge gaps on disaster debris generation as follows: (1) investigate existing technologies for …


Magnetic Resonance Imaging Of Ultrasound Fields For Visualization And Measurement Of Pressure Amplitudes, Paul-Emile Victor Passe-Carlus Oct 2024

Magnetic Resonance Imaging Of Ultrasound Fields For Visualization And Measurement Of Pressure Amplitudes, Paul-Emile Victor Passe-Carlus

Theses and Dissertations

In vivo pressure estimations for therapeutic ultrasound has the potential of rendering treatments using non-invasive ultrasound targeting safer and more reliable. By quantifying pressures and their respective spatial locations, better acoustic predictions and models can be made. In this thesis, we aim to measure a pressure field from a piezo-electric transducer through a ballistic gel medium by using an external gradient coil to encode the pressure field in a way that can be read and quantified using an MRI scanner. We describe the methods and the results pertaining to visualizing a pressure field. The setup was able to capture pressure …


Development Of Temperature Measurement And Control Of 3d Printed Microfluidic Devices Towards Biomolecular Analysis, Derek A. Sanchez Oct 2024

Development Of Temperature Measurement And Control Of 3d Printed Microfluidic Devices Towards Biomolecular Analysis, Derek A. Sanchez

Theses and Dissertations

Microfluidics are devices with channels or reservoirs that have dimensions in the range of micrometers. They have an increasing role in biological analysis processes due to their ability to use very small sample volumes. Many microfluidic processes rely heavily on precise temperature measurement and control. Advances in 3D printing have led to high resolution digital light processing stereolithography (DLP-SLA) printers capable of using bio-compatible materials, available at BYU. This custom 3D printer has a resolution of 7.6 µm in the XY plane and 10 µm in the Z axis. Combined with a custom-made resin, we can produce microfluidic features as …


Design And Analysis Of Optimal Energy Efficient Routing Protocols For Lifetime Maximization And Qos Enhancement In Wireless Body Area Networks, Karthikeyan S Oct 2024

Design And Analysis Of Optimal Energy Efficient Routing Protocols For Lifetime Maximization And Qos Enhancement In Wireless Body Area Networks, Karthikeyan S

Theses and Dissertations

In recent times, Wireless Body Area Networks (WBAN) a subsection of Wireless Sensor Networks (WSN) a promising technology for the future healthcare realm with cutting-edge technologies that can assist healthcare professionals like doctors, nurses and biomedical engineers which enables one-to-one care by implementing Tele-Medicine and Tele-Health solutions. Machine Learning (ML) and Internet of Things (IoT) enabled medical big data is the future of the healthcare sector and Medical Technology-based industries leading to applications in other sectors such as fitness tracking for commercial purposes, Sportsperson health monitoring to track their day-to-day activities and wearable devices for critical and emergency care.

Recent …


Improving Ground-Based Measurements And Understanding Of Mineral Dust And Trace Elements In Ambient Particulate Matter On A Global Scale, Xuan Liu Oct 2024

Improving Ground-Based Measurements And Understanding Of Mineral Dust And Trace Elements In Ambient Particulate Matter On A Global Scale, Xuan Liu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Mineral dust is a major component of ambient particulate matter (PM) globally, affecting visibility, air quality, human health, climate, and biogeochemistry. Dust mass cannot be directly measured and therefore is typically estimated using a dust equation to sum common oxides of major crustal elements based on measured elemental composition data. Both an accurate dust equation and reliable elemental data are essential to accurately estimate dust mass. However, most dust equations fail to account for all major dust compounds, exclude non-dust components of some elements, or account for regional variations in dust composition. Attenuation effects for light elements measured by the …


Thermo-Structural Analysis Of Stiffened Fgm Panels With Cutout Under Non Uniform And Localized In-Plane Edge Loadings, Balaraman P Oct 2024

Thermo-Structural Analysis Of Stiffened Fgm Panels With Cutout Under Non Uniform And Localized In-Plane Edge Loadings, Balaraman P

Theses and Dissertations

Most aerospace applications involve structural components with a high stiffness-toweight ratio and excellent resistance to high temperatures. Buckling, vibration as well as other forms of instability are the consequences of a non uniform stress field caused by non uniform, localized edge loadings and the presence of discontinuities. In order to improve structural properties and increase load bearing capacity, designers concentrate on structural integrity, especially in high-temperature applications. The adaptability and customizable nature of functionally graded material (FGM) make it valuable in addressing these challenges.

Metal-ceramic FGM is an advanced composite material that integrates the distinctive qualities of metal and ceramic …


Synergistic Approaches For Microstructural Refinement, Enhanced Mechanical And Wear Behaviour In Additively Manufactured 17-4 Ph Stainless Steel, Pradeep Kumar S Oct 2024

Synergistic Approaches For Microstructural Refinement, Enhanced Mechanical And Wear Behaviour In Additively Manufactured 17-4 Ph Stainless Steel, Pradeep Kumar S

Theses and Dissertations

The surface and microstructural characteristics of additively manufactured parts play a significant role under mechanical loading. Due to its high strength, tailorable mechanical properties by heat treatment, and ease of printability, the 17-4 precipitation hardened (PH) stainless steel is gaining attention in the additive manufacturing (AM) field.

Selective Laser Melting (SLM), one of the laser-based powder bed fusion (L-PBF) processes, is capable of making fully dense metallic parts with high geometrical fidelity and greater design flexibility at high resolution. The main factors limiting the adoption of SLM are poor surface roughness, anisotropic microstructure, and the formation of micro-pores in the …


Development Of Brain Tumor Detection And Feature Extraction Through Deep Learning Approach, Sivapathi A Oct 2024

Development Of Brain Tumor Detection And Feature Extraction Through Deep Learning Approach, Sivapathi A

Theses and Dissertations

As the body's central control system, the human brain is susceptible to a wide variety of disorders, including tumors characterized by abnormal cell growth. It is imperative to detect these tumors as early as possible to plan effective treatment and improve patient outcomes. By using contemporary medical imaging methods, this research seeks to improve the accuracy and efficiency of brain tumor detection through the careful preprocessing and analysis of images, particularly Magnetic Resonance Imaging (MRI) [1]. To provide context for the subsequent research efforts, the challenges inherent in brain tumor detection are discussed comprehensively, including segmentation accuracy, small lesion detection, …


Evaluation Of Bridge Deterioration Factors: From Design Parameters To Community Impact., Lawrencia Akuffo Oct 2024

Evaluation Of Bridge Deterioration Factors: From Design Parameters To Community Impact., Lawrencia Akuffo

Theses and Dissertations

The structural health and economic variables influencing the state of bridges in New Jersey are thoroughly examined in this thesis. The predictive modeling of bridge conditions using stepwise selection and linear logistic regression approaches is the primary focus of the opening chapter. With its precise predictions about bridge condition, either being fair/good, our model offers insightful information about resource allocation and maintenance by identifying bridge features which affect the deterioration of bridges the most. This gives effective infrastructure management, which not only relies on the identification of the important predictors and their effects on bridge conditions but also ranks them …


Analysis Of Shock Absorption By Spring-Assisted Crutch Tips, Noah Hirschegger, Daegan Caime, Mohamed Atta Oct 2024

Analysis Of Shock Absorption By Spring-Assisted Crutch Tips, Noah Hirschegger, Daegan Caime, Mohamed Atta

Senior Theses

Angel Consulting was originally created to address the problem of excessive wear and tear on the joints of individuals who use crutches for long periods of time. This company has sought to alleviate these issues with a proprietary spring-assisted crutch tip, which reduces the impact of crutch use and will hopefully be able to assist people in alleviating joint damage and discomfort. The team's main purpose is to determine an optimal metric for both marketability and effectiveness and to test the prototype design to ensure the validity of assistance for people who require chronic crutch use. To do this, we …