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Louisiana State University

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Multi-Scale Feedback And Feeding In The Closest Radio Galaxy Centaurus A, B. Mckinley, S. J. Tingay, M. Gaspari, R. P. Kraft, C. Matherne, A. R. Offringa, M. Mcdonald, M. S. Calzadilla, S Veilleux, S. S. Shabala, S. D. J. Gwyn, J. Bland-Hawthorn, D. Crnojevic, B. M. Gaensler, M. Johnston-Hollitt Dec 2021

Multi-Scale Feedback And Feeding In The Closest Radio Galaxy Centaurus A, B. Mckinley, S. J. Tingay, M. Gaspari, R. P. Kraft, C. Matherne, A. R. Offringa, M. Mcdonald, M. S. Calzadilla, S Veilleux, S. S. Shabala, S. D. J. Gwyn, J. Bland-Hawthorn, D. Crnojevic, B. M. Gaensler, M. Johnston-Hollitt

Faculty Publications

Supermassive black holes and supernova explosions at the centres of active galaxies power cycles of outflowing and inflowing gas that affect galactic evolution and the overall structure of the Universe(1,2). While simulations and observations show that this must be the case, the range of physical scales (over ten orders of magnitude) and paucity of available tracers make both the simulation and observation of these effects difficult(3,4). By serendipity, there lies an active galaxy, Centaurus A (NGC 5128)(5,6), at such a close proximity as to allow its observation over this entire range of scales and across the entire electromagnetic spectrum. In …


Deep Underground Neutrino Experiment (Dune) Near Detector Conceptual Design Report, A. Abed Abud, B. Abi, R. Acciarri, M. A. Acero, G. Adamov, D. Adams, M. Adinolfi, A. Aduszkiewicz, Z. Ahmad, J. Ahmed, T. Alion, S. Alonso Monsalve, M. Alrashed, C. Alt, A. Alton, P. Amedo, J. Anderson, C. Andreopoulos, M. P. Andrews, F. Andrianala, S. Andringa, N. Anfimov, A. Ankowski, M. Antonova, S. Antusch, A. Aranda-Fernandez, A. Ariga, L. O. Arnold, M. A. Arroyave, J. Asaadi, A. Aurisano, V. Aushev, D. Autiero Dec 2021

Deep Underground Neutrino Experiment (Dune) Near Detector Conceptual Design Report, A. Abed Abud, B. Abi, R. Acciarri, M. A. Acero, G. Adamov, D. Adams, M. Adinolfi, A. Aduszkiewicz, Z. Ahmad, J. Ahmed, T. Alion, S. Alonso Monsalve, M. Alrashed, C. Alt, A. Alton, P. Amedo, J. Anderson, C. Andreopoulos, M. P. Andrews, F. Andrianala, S. Andringa, N. Anfimov, A. Ankowski, M. Antonova, S. Antusch, A. Aranda-Fernandez, A. Ariga, L. O. Arnold, M. A. Arroyave, J. Asaadi, A. Aurisano, V. Aushev, D. Autiero

Faculty Publications

The Deep Underground Neutrino Experiment (DUNE) is an international, world-class experiment aimed at exploring fundamental questions about the universe that are at the forefront of astrophysics and particle physics research. DUNE will study questions pertaining to the preponderance of matter over antimatter in the early universe, the dynamics of supernovae, the subtleties of neutrino interaction physics, and a number of beyond the Standard Model topics accessible in a powerful neutrino beam. A critical component of the DUNE physics program involves the study of changes in a powerful beam of neutrinos, i.e., neutrino oscillations, as the neutrinos propagate a long distance. …


Spatial Cluster Detection With Threshold Quantile Regression, Junho Lee, Ying Sun, Huixia Judy Wang Dec 2021

Spatial Cluster Detection With Threshold Quantile Regression, Junho Lee, Ying Sun, Huixia Judy Wang

Faculty Publications

Spatial cluster detection, which is the identification of spatial units adjacent in space associated with distinctive patterns of data of interest relative to background variation, is useful for discerning spatial heterogeneity in regression coefficients. Some real studies with regression-based models on air quality data show that there exists not only spatial heterogeneity but also heteroscedasticity between air pollution and its predictors. Since the low air quality is a well-known risk factor for mortality, various cardiopulmonary diseases, and preterm birth, the analysis at the tail would be of more interest than the center of air pollution distribution. In this article, we …


Diving Beneath The Sea Of Stellar Activity: Chromatic Radial Velocities Of The Young Au Mic Planetary System, Bryson Cale, Michael Reefe, Peter Plavchan, Angelle Tanner, Eric Gaidos, Jonathan Gagne, Peter Gao, Stephen R. Kane, Victor J. S. Bejar, Nicolas Lodieu, Guillem Anglada-Escude, Ignasi Ribas, Enric Palle, Andreas Quirrenbach, Pedro Amado, Ansgar Reiners, Jose A. Caballero, Maria Rosa Zapatero Osorio, Stefan Dreizler, Andrew W. Howard, Benjamin J. Fulton, Sharon Xuesong Wang, Kevin I. Collins, Mohammed El Mufti, Justin Wittrock, Emily A. Gilbert, Thomas Barclay, Baptiste Klein, Eder Martioli, Robert Wittenmyer, Duncan Wright, Brett Addison, Teruyuki Hirano, Motohide Tamura, Takayuki Kotani, Norio Narita, David Vermilion, Rena A. Lee, Claire Geneser, Johanna Teske, Samuel N. Quinn, David W. Latham, Gilbert A. Esquerdo, Michael L. Calkins, Perry Berlind, Farzaneh Zohrabi, Caitlin Stibbards, Srihan Kotnana, Jon Jenkins, Joseph D. Twicken, Christopher Henze, Richard Kidwell, Jr., Christopher Burke, Joel Villasenor, Patricia Boyd Dec 2021

Diving Beneath The Sea Of Stellar Activity: Chromatic Radial Velocities Of The Young Au Mic Planetary System, Bryson Cale, Michael Reefe, Peter Plavchan, Angelle Tanner, Eric Gaidos, Jonathan Gagne, Peter Gao, Stephen R. Kane, Victor J. S. Bejar, Nicolas Lodieu, Guillem Anglada-Escude, Ignasi Ribas, Enric Palle, Andreas Quirrenbach, Pedro Amado, Ansgar Reiners, Jose A. Caballero, Maria Rosa Zapatero Osorio, Stefan Dreizler, Andrew W. Howard, Benjamin J. Fulton, Sharon Xuesong Wang, Kevin I. Collins, Mohammed El Mufti, Justin Wittrock, Emily A. Gilbert, Thomas Barclay, Baptiste Klein, Eder Martioli, Robert Wittenmyer, Duncan Wright, Brett Addison, Teruyuki Hirano, Motohide Tamura, Takayuki Kotani, Norio Narita, David Vermilion, Rena A. Lee, Claire Geneser, Johanna Teske, Samuel N. Quinn, David W. Latham, Gilbert A. Esquerdo, Michael L. Calkins, Perry Berlind, Farzaneh Zohrabi, Caitlin Stibbards, Srihan Kotnana, Jon Jenkins, Joseph D. Twicken, Christopher Henze, Richard Kidwell, Jr., Christopher Burke, Joel Villasenor, Patricia Boyd

Faculty Publications

We present updated radial-velocity (RV) analyses of the AU Mic system. AU Mic is a young (22 Myr) early-M dwarf known to host two transiting planets-P-b similar to 8.46 days, R-b = 4.381(-0.18)(+0.18) R-circle plus, P-c similar to 18.86 days, R-c = 3.5(-0.16)(+0.16) R-circle plus. With visible RVs from Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical echelle Spectrographs (CARMENES)-VIS, CHIRON, HARPS, HIRES, MINERVA-Australis, and Tillinghast Reflector Echelle Spectrograph, as well as near-infrared (NIR) RVs from CARMENES-NIR, CSHELL, IRD, iSHELL, NIRSPEC, and SPIRou, we provide a 5 sigma upper limit to the mass of AU …


Search For Lensing Signatures In The Gravitational-Wave Observations From The First Half Of Ligo-Virgo's Third Observing Run, R. Abbott, T. D. Abbott Dec 2021

Search For Lensing Signatures In The Gravitational-Wave Observations From The First Half Of Ligo-Virgo's Third Observing Run, R. Abbott, T. D. Abbott

Faculty Publications

We search for signatures of gravitational lensing in the gravitational-wave signals from compact binary coalescences detected by Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) and Advanced Virgo during O3a, the first half of their third observing run. We study: (1) the expected rate of lensing at current detector sensitivity and the implications of a non-observation of strong lensing or a stochastic gravitational-wave background on the merger-rate density at high redshift; (2) how the interpretation of individual high-mass events would change if they were found to be lensed; (3) the possibility of multiple images due to strong lensing by galaxies or galaxy …


A Deep Learning Framework Identifies Dimensional Representations Of Alzheimer’S Disease From Brain Structure, Zhijian Yang, Ilya M. Nasrallah, Haochang Shou, Junhao Wen, Jimit Doshi, Mohamad Habes, Guray Erus, Ahmed Abdulkadir, Susan M. Resnick, Marilyn S. Albert, Paul Maruff, Jurgen Fripp, John C. Morris, David A. Wolk, Christos Davatzikos, Yong Fan, Vishnu Bashyam, Elizabeth Mamouiran, Randa Melhem, Raymond Pomponio, Dushyant Sahoo, Singh Ashish, Ioanna Skampardoni, Lasya Sreepada, Dhivya Srinivasan, Fanyang Yu, Sindhuja Govindarajan Tirumalai, Yuhan Cui, Zhen Zhou, Katharina Wittfeld, Hans J. Grabe, Duygun Tosun, Murat Bilgel, Yang An Dec 2021

A Deep Learning Framework Identifies Dimensional Representations Of Alzheimer’S Disease From Brain Structure, Zhijian Yang, Ilya M. Nasrallah, Haochang Shou, Junhao Wen, Jimit Doshi, Mohamad Habes, Guray Erus, Ahmed Abdulkadir, Susan M. Resnick, Marilyn S. Albert, Paul Maruff, Jurgen Fripp, John C. Morris, David A. Wolk, Christos Davatzikos, Yong Fan, Vishnu Bashyam, Elizabeth Mamouiran, Randa Melhem, Raymond Pomponio, Dushyant Sahoo, Singh Ashish, Ioanna Skampardoni, Lasya Sreepada, Dhivya Srinivasan, Fanyang Yu, Sindhuja Govindarajan Tirumalai, Yuhan Cui, Zhen Zhou, Katharina Wittfeld, Hans J. Grabe, Duygun Tosun, Murat Bilgel, Yang An

Clinical Research Faculty Publications

Heterogeneity of brain diseases is a challenge for precision diagnosis/prognosis. We describe and validate Smile-GAN (SeMI-supervised cLustEring-Generative Adversarial Network), a semi-supervised deep-clustering method, which examines neuroanatomical heterogeneity contrasted against normal brain structure, to identify disease subtypes through neuroimaging signatures. When applied to regional volumes derived from T1-weighted MRI (two studies; 2,832 participants; 8,146 scans) including cognitively normal individuals and those with cognitive impairment and dementia, Smile-GAN identified four patterns or axes of neurodegeneration. Applying this framework to longitudinal data revealed two distinct progression pathways. Measures of expression of these patterns predicted the pathway and rate of future neurodegeneration. Pattern expression …


On The Role Of Matrix-Weights Elements In Consensus Algorithms For Multi-Agent Systems, Joshua Ogbebor, Xiangyu Meng Dec 2021

On The Role Of Matrix-Weights Elements In Consensus Algorithms For Multi-Agent Systems, Joshua Ogbebor, Xiangyu Meng

Faculty Publications

This paper examines the roles of the matrix weight elements in matrix-weighted consensus. The consensus algorithms dictate that all agents reach consensus when the weighted graph is connected. However, it is not always the case for matrix weighted graphs. The conditions leading to different types of consensus have been extensively analysed based on the properties of matrix-weighted Laplacians and graph theoretic methods. However, in practice, there is concern on how to pick matrix-weights to achieve some desired consensus, or how the change of elements in matrix weights affects the consensus algorithm. By selecting the elements in the matrix weights, different …


Bridge Load Posting Prediction, Sabarethinam Kameshwar, Md. Manik Mia, Sai Bandaru Dec 2021

Bridge Load Posting Prediction, Sabarethinam Kameshwar, Md. Manik Mia, Sai Bandaru

Publications

There are approximately 13,000 bridges in Louisiana facilitating movement of people, goods, and services. At present, about 12% of the bridges are load posted, i.e., they are deemed to lack the strength to safely carry all legal loads. With time bridges will age and deteriorate; at the same time, legal loads might increase. Load posted bridges disrupt the movement of goods and commerce. Therefore, objective of this research was to estimate the number of load posted bridges in Louisiana over the next 50 years. For this purpose, herein, a data based approach was used. For a given bridge type, the …


Smart Battery Management System For Electric Vehicles: Selflearning Algorithms For Simultaneous State And Parameter Estimation, And Stress Detection, Avimanyu Sahoo, Samir Ahmed Dec 2021

Smart Battery Management System For Electric Vehicles: Selflearning Algorithms For Simultaneous State And Parameter Estimation, And Stress Detection, Avimanyu Sahoo, Samir Ahmed

Publications

The project proposes to develop parameter-varying SOH-coupled models for lithium-ion battery and self-learning algorithms to learn the model for simultaneous state and parameter estimation and fault detection. The traditional battery models use constant parameters, limiting their accuracy for predicting the state of the charge and health over the complete life-cycle. In practice, the battery parameters vary with the change in the state of charge and state of health. SOH-coupled models can be used to estimate the state of charge and health accurately. Further, obtaining the model parameters is also a challenging task for designing filters or observers for state estimation. …


Ferris Bakes, Ferris Dehart Dec 2021

Ferris Bakes, Ferris Dehart

Honors Capstones

No abstract provided.


Nonsingular Quantum Gravitational Dynamics Of An Lemaitre-Tolman-Bondi Dust Shell Model: The Role Of Quantization Prescriptions, Kristina Giesel, Bao-Fei Li, Parampreet Singh Nov 2021

Nonsingular Quantum Gravitational Dynamics Of An Lemaitre-Tolman-Bondi Dust Shell Model: The Role Of Quantization Prescriptions, Kristina Giesel, Bao-Fei Li, Parampreet Singh

Faculty Publications

We study some consequences of the loop quantization of the outermost dust shell in the LemaitreTolman-Bondi spacetime with a homogeneous dust density using different quantization strategies motivated by loop quantum gravity. Prior work has dealt with loop quantizing this model by employing holonomies and the triads, following the procedure in standard loop quantum cosmology. In this work we compare this quantization with the one in which holonomies and gauge-covariant fluxes are used. While both of the quantization schemes resolve the central singularity, they lead to different mass gaps at which a trapped surface forms. This trapped surface which is matched …


Memory Forensics Comparison Of Apple M1 And Intel Architecture Using Volatility Framework, Joshua Duke Nov 2021

Memory Forensics Comparison Of Apple M1 And Intel Architecture Using Volatility Framework, Joshua Duke

LSU Master's Theses

Memory forensics allows an investigator to get a full picture of what is occurring on-device at the time that a memory sample is captured and is frequently used to detect and analyze malware. Malicious attacks have evolved from living on disk to having persistence mechanisms in the volatile memory (RAM) of a device and the information that is captured in memory samples contains crucial information for full forensic analysis by cybersecurity professionals. Recently, Apple unveiled computers containing a custom designed system on a chip (SoC) called the M1 that is based on ARM architecture. Our research focused on the differences …


Surface Engineering Of Materials For Optical And Biomedical Applications, Syed Mohammad Abid Hasan Nov 2021

Surface Engineering Of Materials For Optical And Biomedical Applications, Syed Mohammad Abid Hasan

LSU Doctoral Dissertations

The mechanisms of various optical and medical applications depend on the characteristics of the surface of the material which is being used to detect the molecule of interest. In this work, we focused on some specific areas of surface engineering that play a vital role to improve the performance of some material characteristics. Firstly, we focused on the wettability of graphene, which is important for surface modification and thermal/fluidic properties. The level of transparency to van der Waals forces, chemical bonds, and electrostatic interactions between atoms and molecules on two sides of graphene single layer is not well understood. Our …


Optimal Design Problems With State Constraints, Nha Van Tran Nov 2021

Optimal Design Problems With State Constraints, Nha Van Tran

LSU Doctoral Dissertations

This thesis focuses on constrained optimization problems with constraints on the state variables. When the constraints involve partial differential equations or variational inequalities, the optimization problem is also known as Mathematical Programs with Equilibrium Constraints. First, we applied active-set properties of optimal solutions to transform variational inequality constraints into partial differential equation constraints and devised an active-set method which allowed us to solve the optimization problems using the adjoint approach. We extended our approach to evolution problems with constraints on the trajectory of the state variable, such as the irreversibility condition in fracture mechanics. We implemented a gradient descent algorithm …


3-Dimensional Structural Determination Of Epidermal Growth Factor-Like Repeat 27 From Mouse Notch1 Using Nuclear Magnetic Resonance Spectroscopy, Justin Grennell Nov 2021

3-Dimensional Structural Determination Of Epidermal Growth Factor-Like Repeat 27 From Mouse Notch1 Using Nuclear Magnetic Resonance Spectroscopy, Justin Grennell

LSU Doctoral Dissertations

NOTCH1 has been associated with a variety of human ailments, such as cancer and heart disease. NOTCH1 is a transmembrane protein that contains 36 epidermal growth factor-like (EGF) repeats, which facilitate cell signaling by binding proteins on neighboring cells. Each repeat contains about 40 amino acids and has to be folded in a specific manner to function properly. The amino acid sequence, carbohydrate pattern, and calcium-binding sites of EGF-like repeats vary, but the pattern along the 36-repeat chain is conserved. The Abruptex region (EGF24-29) of NOTCH1 is a highly glycosylated (having undergone sugar addition) and flexible region, which gained its …


Non-Adiabatic Excited State Molecular Dynamics Using Ehrenfest And Modulated X-Ray Absorption In Titania, Alexander Matthew Meyer Nov 2021

Non-Adiabatic Excited State Molecular Dynamics Using Ehrenfest And Modulated X-Ray Absorption In Titania, Alexander Matthew Meyer

LSU Doctoral Dissertations

This dissertation contains two separate sections aside from an introduction (Chapter 1): theory and methods (Chapter 2), time dependent density functional theory with Ehrenfest for excited state lifetimes in materials (Chapter 3), and simulated field modulated X-ray absorption in titania (Chapter 4).

Excited state lifetime in insulators and semiconductors can be difficult to compute using quantum chemistry due to their dense excited states. Non-radiative decay in these materials requires the use of non-adiabatic effects to dissipate energy through the means of electron-nuclear coupling such as coherent phonon generation. One method of approaching this challenge in these materials is using Ehrenfest …


An Investigation Examining The Closing Of The Achievement Gap In Louisiana With The Ngss, George Cage Nov 2021

An Investigation Examining The Closing Of The Achievement Gap In Louisiana With The Ngss, George Cage

LSU Doctoral Dissertations

The purpose of this study was to investigate the Next Generation Science Standards (NGSS) and its implications of being a curricular and pedagogical intervention in terms of narrowing the achievement gap in science education for Children of Color. In using the explanatory mixed methods design, standardized test data and one-on-one interviews were examined to assess the effectiveness and impact of the NGSS’ implementation in the state of Louisiana. This study utilized student performance results from the LEAP 2025 to conduct a statistical analysis that measured trends in performance by Children of Color, specifically Black students, before and after the implementation …


Covariant Ergodic Quantum Markov Semigroups Via Systems Of Imprimitivity, Radhakrishnan Balu Nov 2021

Covariant Ergodic Quantum Markov Semigroups Via Systems Of Imprimitivity, Radhakrishnan Balu

Journal of Stochastic Analysis

No abstract provided.


Regional Expansion And Evaluation Of Potential Chemical Control For Invasive Apple Snails (Pomacea Maculata) In Southwest Louisiana, Julian M. Lucero Nov 2021

Regional Expansion And Evaluation Of Potential Chemical Control For Invasive Apple Snails (Pomacea Maculata) In Southwest Louisiana, Julian M. Lucero

LSU Master's Theses

The integration of monitoring and chemical control is an efficient strategy for managing invasive apple snails, Pomacea maculata, in the rice (Oryza sativa L.) and crawfish systems of southwest Louisiana. However, their current distribution, expansion rates, and susceptibility to chemical control methods in this area are not well known. This study evaluated the expansion of P. maculata in southwest Louisiana and assessed potential chemical control for P. maculata among toxicity assays using various application rates. The effects of potential chemical control were also assessed on a non-target species, the red swamp crawfish (Procambarus clarkii). P. maculata …


Numerical Investigation Of The Impact Of Distortion On The Hydrodynamics In The Lower Mississippi River Physical Model (Lmrpm), Ali Heidarizhaleh Nov 2021

Numerical Investigation Of The Impact Of Distortion On The Hydrodynamics In The Lower Mississippi River Physical Model (Lmrpm), Ali Heidarizhaleh

LSU Doctoral Dissertations

The Lower Mississippi River Physical Model (LMRPM) is a distorted-scale, 1:6000 horizontal and 1:400 vertical, movable-bed model that is being used to complement ongoing numerical and field studies directed at studying how non-cohesive sediment transport will be impacted by future changes in relative sea level rise and river discharges, as well various management strategies, such as river sediment diversions, in the lower ~190 miles of the Mississippi River The LMRPM was designed using Froude number (Fr) similarity between the prototype and the model, while the flow Reynolds number is relaxed, but determined to be high enough to ensure rough turbulent …


Congruences Between Coefficients Of A Class Of Eta-Quotients And Their Applications To Combinatorics, Shashika Petta Mestrige Nov 2021

Congruences Between Coefficients Of A Class Of Eta-Quotients And Their Applications To Combinatorics, Shashika Petta Mestrige

LSU Doctoral Dissertations

Ramanujan in $1920$s discovered remarkable congruence properties of the partition function $p(n)$. Later, Watson and Atkin proved these congruences using the theory of modular forms. Atkin, Gordon, and Hughes extended these works to $k$-colored partition functions. In $2010$, Folsom-Kent-Ono and Boylan-Webb proved the congruences of $p(n)$ by studying a $\ell$-adic module associated with a certain sequence of modular functions which are related to $p(n)$.

Primary goal of this thesis is to generalize the work of Atkin, Gordon, Hughes, Folsom-Kent-Ono, and Boylan-Webb about the partition function to a larger class of partition functions. For this purpose we study a closely related …


System Design And Optimization For Efficient Flash-Based Caching In Data Centers, Jian Liu Nov 2021

System Design And Optimization For Efficient Flash-Based Caching In Data Centers, Jian Liu

LSU Doctoral Dissertations

Modern data centers are the backbone of today’s Internet-based services and applications. With the explosive growth of the Internet data and a wider range of data-intensive applications being deployed, it is increasingly challenging for data centers to satisfy the ever-increasing demand for high-quality data services. To relieve the heavy burden on data center systems and accelerate data processing, a popular cost-efficient solution is to deploy high-speed, large-capacity flash-based cache systems. However, we are facing multiple critical challenges from device hardware, systems, to application workloads. In this dissertation, we focus on designing highly efficient caching solutions to cope with the explosive …


Developing A Watershed-Based Plan Evaluation Framework For Socio-Ecological Network Analysis In The Upper Pontchartrain Basin, Lindsey R. Lamana Nov 2021

Developing A Watershed-Based Plan Evaluation Framework For Socio-Ecological Network Analysis In The Upper Pontchartrain Basin, Lindsey R. Lamana

LSU Master's Theses

Louisiana's efforts to create regional watershed planning under the Louisiana Watershed Initiative (LWI) suggest the need to evaluate existing governance systems such as the coordination, development, and implementation of plans. The Network Analysis and Plan Evaluation (NAPE) Framework developed in this study answers initial questions related to the LWI’s long-term resilience outcomes from the content analysis and extraction of relational data in plans of LWI Region 7 located in the Upper Pontchartrain Basin. Actor-Plan Coordination Networks reveal the coordination and collaboration of entities, and a Network of Plans presents the integration of planning documents in the Region. Local government organizations …


Metal Fatigue And Crack Propagation Using Thermodynamic/Thermoelectric Approach, Behnam Hajshirmohammadi Nov 2021

Metal Fatigue And Crack Propagation Using Thermodynamic/Thermoelectric Approach, Behnam Hajshirmohammadi

LSU Doctoral Dissertations

The present dissertation concentrates on the fatigue life of metals and fatigue crack growth (FCG). The basic concept of fatigue thermodynamics is used for this purpose. With the application of thermoelectricity, a method is developed on the basis of fracture fatigue entropy (FFE) for the rapid estimation of the fatigue life of components. To this end, thermoelectric signals captured from a specimen during cyclic loading are analyzed, and a procedure is proposed for the calculation of fatigue life based on the thermoelectric signals in the beginning and the steady-state zone of fatigue. Temperature gradient and electric potential gradients in metals …


Interface-Induced Lattice Structure And Magnetism In Ultrathin Transition Metal Oxide Trilayers, David Howe Nov 2021

Interface-Induced Lattice Structure And Magnetism In Ultrathin Transition Metal Oxide Trilayers, David Howe

LSU Doctoral Dissertations

The study of magnetism has been a rich playground in condensed matter physics due to the multiple mechanisms capable of producing the effect and its relationship to multiple characteristics of a material. Transition metal oxides (TMOs) have been of particular interest for ongoing research into magnetic phenomenon due to the abundance of interesting physical phenomena found in member systems such as colossal magnetoresistance, skyrmion formation, and interface-driven 2D electron gases. Thin films introduce an additional thickness-dependent element, where reduction below a critical thickness eliminates the magnetic coherence of a system and FM order is lost. The atomic structure of these …


De Finetti’S Theorem In Categorical Probability, Tobias Fritz, Tomáš Gonda, Paolo Perrone Nov 2021

De Finetti’S Theorem In Categorical Probability, Tobias Fritz, Tomáš Gonda, Paolo Perrone

Journal of Stochastic Analysis

No abstract provided.


Pore-Scale Modeling Of Fluid Flow And Particle Transport In Multi-Scale Porous Media, Bin Wang Nov 2021

Pore-Scale Modeling Of Fluid Flow And Particle Transport In Multi-Scale Porous Media, Bin Wang

LSU Doctoral Dissertations

Nanomaterials have recently gained much interest in the field of petroleum engineering and environmental engineering. Understanding the particle transport mechanisms in geological porous media is important to design fit-for-purpose nanomaterials and certain operating parameters for practical usage of those materials. It has been known that natural rock has multi-scale porosity (macroporosity and microporosity) in nature. The microporosity can have a strong impact on the flow and mass transport, but the microscale physics and macroscopic consequences remain poorly understood.

The first part of this dissertation introduces a new higher-order, locally mass conserving FEM method. Stokes equation and Darcy equation are solved …


Using Uav Technology Paired With Multispectral Cameras To Assess Crown Rust Epidemics In Oats, Turner A. Graham Nov 2021

Using Uav Technology Paired With Multispectral Cameras To Assess Crown Rust Epidemics In Oats, Turner A. Graham

LSU Master's Theses

Crown rust, caused by Puccinia cornonata f. sp. avenae, is a common disease of oats (Avena sativa) found virtually everywhere oats are cultivated. This disease has caused yield losses of 10 to 40% worldwide. Early detection is important for effective management. A more recently utilized technology in agriculture is unmanned aerial vehicles (UAVs). UAVs, or drones, equipped with cameras are now being used as a resource to take images of fields to identify pests and other issues that may be occurring. Normalized differentiated vegetative index (NDVI) is a numerical indicator used to determine the vegetative health of …


Temperature Affects The Time Required To Discern The Relationship Between Primary Production And Export Production In The Ocean, Edward Laws, Kanchan Maiti Nov 2021

Temperature Affects The Time Required To Discern The Relationship Between Primary Production And Export Production In The Ocean, Edward Laws, Kanchan Maiti

Faculty Publications

No abstract provided.


Temperature Affects The Time Required To Discern The Relationship Between Primary Production And Export Production In The Ocean, Edward Laws, Kanchan Maiti Nov 2021

Temperature Affects The Time Required To Discern The Relationship Between Primary Production And Export Production In The Ocean, Edward Laws, Kanchan Maiti

Faculty Publications

No abstract provided.