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2023

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Articles 1201 - 1230 of 9777

Full-Text Articles in Engineering

Effect Of Hf Alloying On Magnetic, Structural, And Magnetostrictive Properties In Feco Films For Magnetoelectric Heterostructure Devices, Thomas Mion, Margo Staruch, Konrad Bussmann, Goran Karapetrov, Olaf Van 'T Erve, Sara Mills, Heonjune Ryou, Ramasis Goswami, Patrick G. Callahan, David J. Rowenhorst, Syed B. Qadri, Samuel Lofland, Peter Finkel Nov 2023

Effect Of Hf Alloying On Magnetic, Structural, And Magnetostrictive Properties In Feco Films For Magnetoelectric Heterostructure Devices, Thomas Mion, Margo Staruch, Konrad Bussmann, Goran Karapetrov, Olaf Van 'T Erve, Sara Mills, Heonjune Ryou, Ramasis Goswami, Patrick G. Callahan, David J. Rowenhorst, Syed B. Qadri, Samuel Lofland, Peter Finkel

College of Science & Mathematics Departmental Research

Materials with high magnetoelectric coupling are attractive for use in engineered multiferroic heterostructures with applications such as ultra-low power magnetic sensors, parametric inductors, and non-volatile random-access memory devices. Iron-cobalt alloys exhibit both high magnetostriction and high saturation magnetization that are required for achieving significantly higher magnetoelectric coupling. We report on sputter-deposited (Fe0.5Co0.5)1-xHfx (x = 0 - 0.14) alloy thin films and the beneficial influence of Hafnium alloying on the magnetic and magnetostrictive properties. We found that co-sputtering Hf results in the realization of the peening mechanism that drives film stress from highly tensile to slightly compressive. Scanning electron microscopy and …


System-Level Noise Performance Of Coherent Imaging Systems, Derek J. Burrell, Joshua H. Follansbee, Mark F. Spencer, Ronald G. Driggers Nov 2023

System-Level Noise Performance Of Coherent Imaging Systems, Derek J. Burrell, Joshua H. Follansbee, Mark F. Spencer, Ronald G. Driggers

Faculty Publications

We provide an in-depth analysis of noise considerations in coherent imaging, accounting for speckle and scintillation in addition to “conventional” image noise. Specifically, we formulate closed-form expressions for total effective noise in the presence of speckle only, scintillation only, and speckle combined with scintillation. We find analytically that photon shot noise is uncorrelated with both speckle and weak-to-moderate scintillation, despite their shared dependence on the mean signal. Furthermore, unmitigated speckle and scintillation noise tends to dominate coherent-imaging performance due to a squared mean-signal dependence. Strong coupling occurs between speckle and scintillation when both are present, and we characterize this behavior …


11.06.2023 Orsp Connect, Liz Williamson Nov 2023

11.06.2023 Orsp Connect, Liz Williamson

ORED Newsletter

No abstract provided.


Advanced Multiscale Molecular Dynamics Simulations Of Amorphous Polymers, Sahar Zenoozi Nov 2023

Advanced Multiscale Molecular Dynamics Simulations Of Amorphous Polymers, Sahar Zenoozi

USF Tampa Graduate Theses and Dissertations

Polymers are in a wide range of material forms with various resources, including natural to synthetic processes. Polymers consist of covalently bonded monomers to each other. The chain length of polymers varies from a few monomers to thousands of monomers. This wide range of chain length enables polymers with attractive capabilities of chemical and physical properties. Thus, polymers are highly attractive in different scientific and industrial applications such as drug delivery, optical coatings, catalysts, semiconductors and organic photovoltaics. This work has combined updated accurate methods for accurate initial conformations, and modified force field parameters to produce a generalized method for …


Wind Farm Optimization And Analysis Of Complex Wake Structures, Rubel Chandra Das Nov 2023

Wind Farm Optimization And Analysis Of Complex Wake Structures, Rubel Chandra Das

Mechanical Engineering ETDs

A high-fidelity computational solver was developed with direct numerical simulation (DNS), large eddy simulation (LES), and Concurrent Precursor Method (CPM) capabilities. Extensive validation ensured the solver's accuracy in modeling fluid dynamics, including the wake characteristics of both utility and miniature-scale wind turbines. Key performance statistics (e.g., velocity and turbulence intensity profiles) were compared against established theoretical, computational, and experimental results. The study examined the influence of ground clearance on turbine performance, comparing two scenarios with different hub heights. Results showed that larger ground clearance facilitates quicker wake recovery. Finally, the study uses a nine-turbine array model to explore wind farm …


A Definition Of Reliable Water Supply For Public Water Systems, Easton Hopkins Nov 2023

A Definition Of Reliable Water Supply For Public Water Systems, Easton Hopkins

Theses and Dissertations

"Reliable water supply" does not have a universal definition in Utah, or the Western United States, where water resources are limited and such a definition would be especially useful. Utah's three water agencies and 500 public water systems have no consistent method to define, evaluate, and report it, potentially leading to an inability to meet regulatory water demands. We propose a unified definition of reliable water supply for Utah's public water suppliers that can also be used elsewhere. The qualitative definition we propose is necessary to precede quantitative evaluations, set policy, and provide consistency to water resources management in Utah. …


Machine Learning Applications And Sustainable Development, Vishnu Pendyala Nov 2023

Machine Learning Applications And Sustainable Development, Vishnu Pendyala

Open Educational Resources

This presentation, "Machine Learning Applications and Sustainable Development," explores the intersection of machine learning and its impact on privacy, equity, and societal well-being. It delves into the potential for re-identification of "anonymized" data through various techniques like k-anonymity, L-diversity, and the vulnerabilities of large language models, illustrating these concepts with real-world examples such as the AOL search data, Netflix Prize dataset, and Strava's fitness tracking. The presentation also discusses solutions to enhance data privacy, including differential privacy and the emerging field of machine unlearning, highlighting their applications and limitations. Finally, it addresses the broader implications for civil rights and ethical …


An Ontology Design Pattern For Representing Causality, Utkarshani Jaimini, Cory Henson, Amit Sheth Nov 2023

An Ontology Design Pattern For Representing Causality, Utkarshani Jaimini, Cory Henson, Amit Sheth

Publications

The causal pattern is a proposed ontology design pattern for representing the structure of causal relations in a knowledge graph. This pattern is grounded in the concepts defined and used by the CausalAI community i.e., Causal Bayesian Networks and do-calculus. Specifically, the pattern models three primary concepts: (1) causal relations, (2) causal event roles, and (3) causal effect weights. Two use cases involving a sprinkler system and asthma patients are provided along with their relevant competency questions.


Computational Modeling Using A Novel Continuum Approach Coupled With Pathway-Informed Neural Networks To Optimize Dynein-Mediated Centrosome Positioning In Polarized Cells, Arkaprovo Ghosal, Padmanabhan Seshaiyar Dr., Adriana Dawes Dr., General Genomics Inc. Nov 2023

Computational Modeling Using A Novel Continuum Approach Coupled With Pathway-Informed Neural Networks To Optimize Dynein-Mediated Centrosome Positioning In Polarized Cells, Arkaprovo Ghosal, Padmanabhan Seshaiyar Dr., Adriana Dawes Dr., General Genomics Inc.

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Modeling Social Dynamics Through Coupling Mechanistic Models With Generative Artificial Intelligence, Navid Ghaffarzadegan, Ross Williams, Aritra Majumdar, Niyousha Hosseinichimeh Nov 2023

Modeling Social Dynamics Through Coupling Mechanistic Models With Generative Artificial Intelligence, Navid Ghaffarzadegan, Ross Williams, Aritra Majumdar, Niyousha Hosseinichimeh

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


A Behavioral Epidemic Model: A Simulation And Empirical Analysis, Ann Osi, Navid Ghaffarzadegan Nov 2023

A Behavioral Epidemic Model: A Simulation And Empirical Analysis, Ann Osi, Navid Ghaffarzadegan

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


New Dual Modality Technique Of Gamma-Ray Densitometry (Grd) And Optical Fiber Probe (Ofp) To Investigate Line-Averaged Diameter Profiles Of Gas, Liquid, And Solid Holdups Along The Height Of A Slurry Bubble Column, Omar Farid, Binbin Qi, Sebastián Uribe, Muthanna H. Al-Dahhan Nov 2023

New Dual Modality Technique Of Gamma-Ray Densitometry (Grd) And Optical Fiber Probe (Ofp) To Investigate Line-Averaged Diameter Profiles Of Gas, Liquid, And Solid Holdups Along The Height Of A Slurry Bubble Column, Omar Farid, Binbin Qi, Sebastián Uribe, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

A new hybrid measurement technique was developed and employed to study line-averaged three-phase holdup distribution in a Slurry Bubble Column Reactor (SBCR) using gamma-ray densitometry (GRD) and point optical fiber probe (OFP) techniques. The OFP technique was used to measure the local gas holdup at 45 nodes in the cross-section area of the SBCR at three different axial levels. Thus, the GRD technique measured the spectrum of the SBCR for two different orientations simultaneously with the OFP technique at the same operating conditions to determine the solid holdup distribution radially and axially. The line-averaged solid holdup for 25% solids loading …


Optimal And Robust Control Problems Of Microalgae Cultivation, Mariana Rodriguez-Jara, Luis A. Ricardez-Sandoval, Carlos E. Ramirez-Castelan, Hector Puebla Nov 2023

Optimal And Robust Control Problems Of Microalgae Cultivation, Mariana Rodriguez-Jara, Luis A. Ricardez-Sandoval, Carlos E. Ramirez-Castelan, Hector Puebla

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Novel Systems Engineering Framework Analysis Of Photovoltaic Models And Equations, Peter R. Michael Nov 2023

Novel Systems Engineering Framework Analysis Of Photovoltaic Models And Equations, Peter R. Michael

USF Tampa Graduate Theses and Dissertations

This dissertation analyzes Photovoltaic PV equations and models for silicon based systems from a Systems Engineering framework. Background information includes an introduction, a summary of the state of PV use, a brief history of photovoltaics, and the detailed derivation of equations that enable the finding of the PV parameters contained in the PV models.The novel inquiry, leveraging systems engineering frameworks, includes three areas useful in analyzing PV equations and models. The first is a statistical verification of common simplifications of PV equations at the primary conditions of short circuit, open circuit, and maximum power. Additional analysis shows other simplifications that …


Bridging Domain Gaps For Cross-Spectrum And Long-Range Face Recognition Using Domain Adaptive Machine Learning, Cedric Armel Nimpa Fondje Nov 2023

Bridging Domain Gaps For Cross-Spectrum And Long-Range Face Recognition Using Domain Adaptive Machine Learning, Cedric Armel Nimpa Fondje

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Face recognition technology has witnessed significant advancements in recent decades, enabling its widespread adoption in various applications such as security, surveillance, and biometrics applications. However, one of the primary challenges faced by existing face recognition systems is their limited performance when presented with images from different modalities or domains( such as infrared to visible, long range to close range, nighttime to daytime, profile to f rontal, etc.) Additionally, advancements in camera sensors, analytics beyond the visible spectrum, and the increasing size of cross-modal datasets have led to a particular interest in cross-modal learning for face recognition in the biometrics and …


Profess 12: Project Report Pr4: The Profess 12 Summer School Toolkit, Una Beagon, Margaret Morgan, Ruchita Jani, Rosalind M Henry, Janet Mckennedy, Brian Bowe Nov 2023

Profess 12: Project Report Pr4: The Profess 12 Summer School Toolkit, Una Beagon, Margaret Morgan, Ruchita Jani, Rosalind M Henry, Janet Mckennedy, Brian Bowe

Reports

This document forms part of the PROFESS 12 Summer School Toolkit for engineering educators as a component of Work Package 3 in the HEA funded PROFESS 12 (PROFessional skills for Engineering students - Summer School to achieve SDG 12) Project.

This handbook outlines the pedagogical background to the design of the Summer School and describes in detail the components of each session, outlining the aims and objectives, teaching and learning activities and links to resources or templates as required. Educators are encouraged to provide feedback or additional relevant resources to the project team for inclusion as alternative options.

A student …


Performance Evaluation Of Millimeter Wave – Mimo System Based On Hybrid Precoding And Combining, Youstina.N. Samir, Fayez .W. Zaki, Hala .B. Nafea Nov 2023

Performance Evaluation Of Millimeter Wave – Mimo System Based On Hybrid Precoding And Combining, Youstina.N. Samir, Fayez .W. Zaki, Hala .B. Nafea

Mansoura Engineering Journal

In 5G wireless communication network, the mmwave used in most applications to provides high data rates, low latency, high system capacity, and huge available bandwidths, but in multiuser case in mmwave frequency range occurs high path loss and decreasing the system performance. The efficient way to achieve high performance large antenna arrays is hybrid precoding techniques that shall be applied at the base stations (BS) and Mobile Stations (MS). It's found that the full digital precoding with large antenna arrays consumes high power and high hardware cost. In this paper, the current work presents low complexity hybrid precoding and combining …


Multicellular And Multiscale Models Of Microbes And Host Systems, Elebeoba May Nov 2023

Multicellular And Multiscale Models Of Microbes And Host Systems, Elebeoba May

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Kinetic Optimization Of The Batch Crystallization Of An Active Pharmaceutical Ingredient In The Presence Of A Low-Solubility, Precipitating Impurity, Mitchell Paolello, Ilyes Bichari, Davinia Brouckaert, Mirvatte Francis, Dawn Yang, Gerard Capellades Nov 2023

Kinetic Optimization Of The Batch Crystallization Of An Active Pharmaceutical Ingredient In The Presence Of A Low-Solubility, Precipitating Impurity, Mitchell Paolello, Ilyes Bichari, Davinia Brouckaert, Mirvatte Francis, Dawn Yang, Gerard Capellades

Henry M. Rowan College of Engineering Departmental Research

The presence of impurities above regulatory thresholds has been responsible for recent recalls of pharmaceutical drugs. Crystallization is one of the most used separation processes to control impurities in the final drug. A particular issue emerges when impurities are poorly soluble in the crystallization solvent and simultaneously precipitate with the product. This publication reports the development of a population balance model to investigate if the impurity crystallization kinetics can be selectively inhibited in a seeded batch crystallization system containing acetaminophen (ACM), a commonly used small-molecule active pharmaceutical ingredient (API), and curcumin (CUR), a simulated low-solubility/co-precipitating impurity. Raman spectroscopy was used …


A Multi-Organ Maize Metabolic Model Connects Temperature Stress With Energy Production And Reducing Power Generation, Niaz Bahar Chowdhury, Margaret Simons- Senftle, Berengere Decouard, Isabelle Quillere, Martine Rigault, Karuna Anna Sajeevan, Bibek Acharya, Ratul Chowdhury, Bertrand Hirel, Alia Dellagi, Costas Maranas, Rajib Saha Nov 2023

A Multi-Organ Maize Metabolic Model Connects Temperature Stress With Energy Production And Reducing Power Generation, Niaz Bahar Chowdhury, Margaret Simons- Senftle, Berengere Decouard, Isabelle Quillere, Martine Rigault, Karuna Anna Sajeevan, Bibek Acharya, Ratul Chowdhury, Bertrand Hirel, Alia Dellagi, Costas Maranas, Rajib Saha

Department of Chemical and Biomolecular Engineering: Faculty Publications

Climate change has adversely affected maize productivity. Thereby, a holistic understanding of metabolic crosstalk among its organs is important to address this issue. Thus, we reconstructed the first multi-organ maize metabolicmodel, iZMA6517, and contextualized itwith heat and cold stress transcriptomics data using expression distributed reaction flux measurement (EXTREAM) algorithm. Furthermore, implementing metabolic bottleneck analysis on contextualized models revealed differences between these stresses. While both stresses had reducing power bottlenecks, heat stress had additional energy generation bottlenecks.We also performed thermodynamic driving force analysis, revealing thermodynamics-reducing power-energy generation axis dictating the nature of temperature stress responses. Thus, a temperaturetolerant maize ideotype can …


Nano Composite Piezo-Responsive Foam Enabled Pressure Mapping, Jake Duane Sundet Nov 2023

Nano Composite Piezo-Responsive Foam Enabled Pressure Mapping, Jake Duane Sundet

Theses and Dissertations

Pressure injuries cause pain both physically and financially. By creating a comfortable pressure mapping system, pressure injuries can more easily be prevented, and a large expenditure avoided. Nano composite piezo-responsive foam (NCPF) is an inexpensive foam that can be used to measure a static load while still providing a comfortable interface. As NCPF compresses, the impedance changes, correlating to a change in pressure. Optimizing electrode geometry is needed to take full advantage of the impedance change NCPF incurs upon deformation. To optimize electrode geometry, a design of experiment was performed which concluded that a one square inch area of interlaced …


Optimal Inverter-Based Resource Installation To Minimize Technical Energy Losses In Distribution Systems, Felipe B. Dantas, Damasio Fernandes, Washington L.A. Neves, Alana K.X.B. Branco, Flavio Costa Nov 2023

Optimal Inverter-Based Resource Installation To Minimize Technical Energy Losses In Distribution Systems, Felipe B. Dantas, Damasio Fernandes, Washington L.A. Neves, Alana K.X.B. Branco, Flavio Costa

Michigan Tech Publications

This paper proposes an algorithm for the optimal installation of inverter-based resources (IBR) composed of wind energy conversion systems, photovoltaic systems, and battery energy storage systems in distribution systems using genetic algorithm (GA) and the cuckoo search (CS) as optimization techniques. The OpenDSS software is used to calculate the power flow in the distribution system with different penetration levels of IBRs. It is used a standard load shape of the IEEE 123 bus system programmed in OpenDSS and irradiance, temperature, and wind speed curves from Brazil. The proposed algorithm, using a genetic algorithm and cuckoo search, was able to define …


Wire Electrical Discharge Machining Of Aisi304 And Aisi316 Alloys: A Comparative Assessment Of Machining Responses, Empirical Modeling And Multi-Objective Optimization, Mona Aboueleaz, Noha Naeim, Islam Abdelgaliel, Mohamed Aly, Ahmed Elkaseer Nov 2023

Wire Electrical Discharge Machining Of Aisi304 And Aisi316 Alloys: A Comparative Assessment Of Machining Responses, Empirical Modeling And Multi-Objective Optimization, Mona Aboueleaz, Noha Naeim, Islam Abdelgaliel, Mohamed Aly, Ahmed Elkaseer

Mechanical Engineering

This research investigates the multi-response of both material removal rate (MRR) and surface roughness (Ra) for the wire electrical discharge machining (WEDM) of two stainless steel alloys: AISI 304 and AISI 316. Experimental results are utilized to compare the machining responses obtained for AISI 316 with those obtained for AISI 304, as previously reported in the literature. The experimental work is conducted through a full factorial experimental design of five running parameters with different levels: applied voltage, transverse feed, pulse-on/pulse-off times and current intensity. The machined workpieces are analyzed using an image processing technique in order to evaluate the size …


Integrated Periphyton Biofilters In Marine Recirculating Aquaculture Systems, Adam N. Bell Nov 2023

Integrated Periphyton Biofilters In Marine Recirculating Aquaculture Systems, Adam N. Bell

USF Tampa Graduate Theses and Dissertations

Marine aquaculture is a growing industry that has the potential to reduce eutrophication, overfishing, and loss of biodiversity. Recirculating aquaculture systems (RAS) are a type of aquaculture system that decreases discharge, raises biological control, and conserves water; however, RAS are challenged due to high energy cost, low biodiversity, water quality control, and waste nutrients. Periphyton biofilters are a new technology that allows for feed production, water quality control, microbial diversity, and resource recovery in marine aquaculture systems. The overarching question that this dissertation investigates is, how can periphyton biofilters be integrated into RAS to address the challenges of modern sustainable …


Synthetic Aperture Scatter Imaging, Qian Huang, Zhipeng Dong, Gregory Nero, Yuzuru Takashima, Timothy J. Schulz, David J. Brady Nov 2023

Synthetic Aperture Scatter Imaging, Qian Huang, Zhipeng Dong, Gregory Nero, Yuzuru Takashima, Timothy J. Schulz, David J. Brady

Michigan Tech Publications

Diffraction limits the minimum resolvable feature on remotely observed targets to $\lambda R_{c}/A_{c}$, where $\lambda$ is the operating wavelength, $R_{c}$ is the range to the target and $A_{c}$ is the diameter of the observing aperture. Resolution is often further reduced by scatter or turbulence. Here we show that analysis of scattered coherent illumination can be used to achieve resolution proportional to $\lambda R_{s}/A_{s}$, where $R_{s}$ is the range between the scatterer and the target and $A_{s}$ is the diameter of the observed scatter. Theoretical analysis suggests that this approach can yield resolution up to 1000× better than the diffraction limit. …


A Novel Application Of Spinning Disk Technology To Collect Plasma From Whole Blood Prior To Quantifying Plasma Rna, Naomi Rapier-Sharman, Mae-Lynn L. Hutchinson, Carlos M. Moreno, Abraham Quaye, Brian D. Poole, K. Scott Weber, William G. Pitt, Brett E. Pickett Nov 2023

A Novel Application Of Spinning Disk Technology To Collect Plasma From Whole Blood Prior To Quantifying Plasma Rna, Naomi Rapier-Sharman, Mae-Lynn L. Hutchinson, Carlos M. Moreno, Abraham Quaye, Brian D. Poole, K. Scott Weber, William G. Pitt, Brett E. Pickett

Faculty Publications

The spinning disk technology has previously been utilized to isolate bacterial components from blood in hours instead of days. We hypothesized that this platform could be applied as an alternative approach to isolating plasma RNA from a whole blood sample. We consequently tested the efficacy of the spinning disk technology to extract plasma from whole blood upstream of RNA isolation and analysis. To do so, we collected plasma using either the spinning disk or the typical two-spin centrifuge method. We found that the spinning disk method results in significantly more hemolysis during collection than the conventional two-spin centrifuge method. However, …


S-Net: A Multiple Cross Aggregation Convolutional Architecture For Automatic Segmentation Of Small/Thin Structures For Cardiovascular Applications, Nan Mu, Zonghan Lyu, Mostafa Rezaeitaleshmahalleh, Cassie Bonifas, Jordan Gosnell, Marcus Haw, Joseph Vettukattil, Jingfeng Jiang Nov 2023

S-Net: A Multiple Cross Aggregation Convolutional Architecture For Automatic Segmentation Of Small/Thin Structures For Cardiovascular Applications, Nan Mu, Zonghan Lyu, Mostafa Rezaeitaleshmahalleh, Cassie Bonifas, Jordan Gosnell, Marcus Haw, Joseph Vettukattil, Jingfeng Jiang

Michigan Tech Publications

With the success of U-Net or its variants in automatic medical image segmentation, building a fully convolutional network (FCN) based on an encoder-decoder structure has become an effective end-to-end learning approach. However, the intrinsic property of FCNs is that as the encoder deepens, higher-level features are learned, and the receptive field size of the network increases, which results in unsatisfactory performance for detecting low-level small/thin structures such as atrial walls and small arteries. To address this issue, we propose to keep the different encoding layer features at their original sizes to constrain the receptive field from increasing as the network …


Research Outreach Interdisciplinary Activity To Classify Olive Oil Blends Integrating Multicolor Imaging, Image Processing, And Machine Learning, Allan Abraham, Kameshwaran Balachandran Nov 2023

Research Outreach Interdisciplinary Activity To Classify Olive Oil Blends Integrating Multicolor Imaging, Image Processing, And Machine Learning, Allan Abraham, Kameshwaran Balachandran

Undergraduate Research (Journal)

This outreach undergraduate research project presents a low-cost method to distinguish the quality of different olive oils. The proposed method is based on an indirect measurement of the chlorophyll molecules present when a green laser diode illuminates the oil sample. Oil blends can be classified into five classes (no olive oil, light olive oil, medium olive oil, olive oil, and extra virgin olive oil) by quantifying the ratio of the red channel versus the green channel along the laser illumination path from a color image. After labeling each oil blend, a convolutional neural network has been implemented and trained to …


Development, Implementation, And Evaluation Of Swirl-Combustion Strategies For Optimal Performance Of Ammonia As A Fuel For Gas Turbine Engines, Varun Nanjunda Rao Viswamithra Nov 2023

Development, Implementation, And Evaluation Of Swirl-Combustion Strategies For Optimal Performance Of Ammonia As A Fuel For Gas Turbine Engines, Varun Nanjunda Rao Viswamithra

LSU Doctoral Dissertations

In an effort to reduce harmful effects of greenhouse gas emissions, ammonia is being pursued as a fuel for power generation as it is a carbon-free energy source. However, the use of ammonia-air mixtures in premixed swirl combustors poses challenges due to low flame speed and reactivity resulting in combustor stability issues in addition to high Nitrous Oxide (NOx) emissions due to the presence of fuel-bound Nitrogen. The first part of this study attempts to overcome lean blowout limits of methane-ammonia-air mixtures using a novel, multi-point () injection strategy, whereby micron-sized holes on the swirler vanes generate a co-flowing stream …


Biological Seawater Desalination Using Green Algae And Cyanobacteria, Abdul Mannan Zafar Nov 2023

Biological Seawater Desalination Using Green Algae And Cyanobacteria, Abdul Mannan Zafar

Thesis/ Dissertation Defenses

Water shortage in many coastal parts of the world is reaching alarming situation, including the United Arab Emirates. Urbanization and rapid population growth are generating critical water demands with an increase in per capita consumption. Seawater is usually treated by membrane processes such as reverse osmosis (RO). However, this technology is energy intensive and generates excessive brine as a waste. The solution to this problem can be found in natural remediation techniques that can reduce salt concentration from seawater, such as halophytes. A salt-tolerant species can consume Na+ and Clions and increase cellular growth which is termed biological desalination or …