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Invariants For Turaev Genus One Links, Oliver T. Dasbach, Adam M. Lowrance Jan 2018

Invariants For Turaev Genus One Links, Oliver T. Dasbach, Adam M. Lowrance

Faculty Publications

The Turaev genus defines a natural filtration on knots where Turaev genus zero knots are precisely the alternating knots. We show that the signature of a Turaev genus one knot is determined by the number of components in its all-A Kaufiman state, the number of positive crossings, and its determinant. We also show that either the leading or trailing coeficient of the Jones polynomial of a Turaev genus one link (or an almost alternating link) has absolute value one.


Stability And Robustness Analysis For Switched Systems With Time-Varying Delays, Frédéric Mazenc, Michael Malisoff, Hitay Özbay Jan 2018

Stability And Robustness Analysis For Switched Systems With Time-Varying Delays, Frédéric Mazenc, Michael Malisoff, Hitay Özbay

Faculty Publications

A new technique is presented for the stability and robustness analysis of nonlinear switched time-varying systems with uncertainties and time-varying delays. The delays are allowed to be discontinuous (but are required to be piecewise continuous) and arbitrarily long with known upper bounds. The technique uses an adaptation of Halanay’s inequality and a trajectory-based technique, and is used for designing switched controllers to stabilize linear time-varying systems with time-varying delays.


Strong Converse For The Feedback-Assisted Classical Capacity Of Entanglement-Breaking Channels, D. Ding, M. M. Wilde Jan 2018

Strong Converse For The Feedback-Assisted Classical Capacity Of Entanglement-Breaking Channels, D. Ding, M. M. Wilde

Faculty Publications

Quantum entanglement can be used in a communication scheme to establish a correlation between successive channel inputs that is impossible by classical means. It is known that the classical capacity of quantum channels can be enhanced by such entangled encoding schemes, but this is not always the case. In this paper, we prove that a strong converse theorem holds for the classical capacity of an entanglement-breaking channel even when it is assisted by a classical feedback link from the receiver to the transmitter. In doing so, we identify a bound on the strong converse exponent, which determines the exponentially decaying …


Gluten-Free Bakery And Pasta Products: Prevalence And Quality Improvement, Yupeng Gao, Marlene E. Janes, Busarawan Chaiya, Margaret A. Brennan, Charles S. Brennan, Witoon Prinyawiwatkul Jan 2018

Gluten-Free Bakery And Pasta Products: Prevalence And Quality Improvement, Yupeng Gao, Marlene E. Janes, Busarawan Chaiya, Margaret A. Brennan, Charles S. Brennan, Witoon Prinyawiwatkul

Faculty Publications

An increasing demand of gluten-free (GF) products is caused by a growing number of diagnosed coeliacs and a consumption trend to eliminate allergenic proteins from diet. Driven by the rapidly growing market, comprehensive understanding of GF products is necessary. The purpose of this review was to concisely present an overview of various approaches to improve physicochemical and sensory qualities of GF bread, cake/muffin and pasta/noodle products. Some novel techniques used in GF products were discussed in this review. These techniques included the use of different alternative flours (including GF cereals, pseudo-cereals, legume flours, fruit and vegetable powders and seafood powders), …


Evaluation Of Certain Hypergeometric Functions Over Finite Fields, Fang Ting Tu, Yifan Yang Jan 2018

Evaluation Of Certain Hypergeometric Functions Over Finite Fields, Fang Ting Tu, Yifan Yang

Faculty Publications

For an odd prime p, let φ denote the quadratic character of the multiplicative group Fp×, where Fp is the finite field of p elements. In this paper, we will obtain evaluations of the hypergeometric functions 2F1(Formula presented), x ∈ Fp, x ≠ 0, 1, over Fp in terms of Hecke character attached to CM elliptic curves for characters ψ of Fp× of order 3, 4, 6, 8, and 12.


The Ericksen Model Of Liquid Crystals With Colloidal And Electric Effects, Ricardo H. Nochetto, Shawn W. Walker, Wujun Zhang Jan 2018

The Ericksen Model Of Liquid Crystals With Colloidal And Electric Effects, Ricardo H. Nochetto, Shawn W. Walker, Wujun Zhang

Faculty Publications

We present a robust discretization of the Ericksen model of liquid crystals with variable degree of orientation coupled with colloidal effects and electric fields. The total energy consists of the Ericksen energy, a weak anchoring (or penalized Dirichlet) energy to model colloids, and an electrical energy for a given electric field. We describe our special discretization of the total energy along with a method to compute minimizers via a discrete quasi-gradient flow algorithm which has a strictly monotone energy decreasing property. Numerical experiments are given in two and three dimensions to illustrate that the method is able to capture non-trivial …


Convergence Analysis Of A Finite Element Approximation Of Minimum Action Methods, Xiaoliang Wan, Haijun Yu, Jiayu Zhai Jan 2018

Convergence Analysis Of A Finite Element Approximation Of Minimum Action Methods, Xiaoliang Wan, Haijun Yu, Jiayu Zhai

Faculty Publications

In this work, we address the convergence of a finite element approximation of the minimizer of the Freidlin–Wentzell (F-W) action functional for nongradient dynamical systems perturbed by small noise. The F-W theory of large deviations is a rigorous mathematical tool to study small-noise-induced transitions in a dynamical system. The central task in the application of F-W theory of large deviations is to seek the minimizer and minimum of the F-W action functional. We discretize the F-W action functional using linear finite elements and establish the convergence of the approximation through G-convergence.


Tourmaline Compositions And Textures: Reflections Of The Fluid Phase, Barbara L. Dutrow, Darrell J. Henry Jan 2018

Tourmaline Compositions And Textures: Reflections Of The Fluid Phase, Barbara L. Dutrow, Darrell J. Henry

Faculty Publications

© 2018, Czech Geological Survey. All rights reserved. Tourmaline uniquely records evidence of its geologic history in its composition and, if properly decoded, provides insight into the geologic environment of formation. Recent studies suggest that tourmaline not only retains chemical information on the host-rock environment, but also provides signatures on the fluid phase with which it interacted. Such signatures are embedded in its major-and minor-element compositions as well as in its isotopes. Some of these elemental signatures are qualitative, while others provide quantitative evaluation of the evolving fluid-phase compositions. Chemical fingerprints of interacting fluids are found as compositional variations in …


Cylindrical Shell With Junctions: Uncertainty Quantification Of Free Vibration And Frequency Response Analysis, Harri Hakula, Vesa Kaarnioja, Mikael Laaksonen, Aly Mousaad Aly Jan 2018

Cylindrical Shell With Junctions: Uncertainty Quantification Of Free Vibration And Frequency Response Analysis, Harri Hakula, Vesa Kaarnioja, Mikael Laaksonen, Aly Mousaad Aly

Faculty Publications

Numerical simulation of thin solids remains one of the challenges in computational mechanics. The 3D elasticity problems of shells of revolution are dimensionally reduced in different ways depending on the symmetries of the configurations resulting in corresponding 2D models. In this paper, we solve the multiparametric free vibration of complex shell configurations under uncertainty using stochastic collocation with the p-version of finite element method and apply the collocation approach to frequency response analysis. In numerical examples, the sources of uncertainty are related to material parameters and geometry representing manufacturing imperfections. All stochastic collocation results have been verified with Monte Carlo …


Modeling A New Design For Extracting Energy From Geopressured Geothermal Reservoirs, Esmail Ansari, Richard Hughes, Christopher D. White Jan 2018

Modeling A New Design For Extracting Energy From Geopressured Geothermal Reservoirs, Esmail Ansari, Richard Hughes, Christopher D. White

Faculty Publications

Reducing geothermal energy recovery costs and environmental concerns has led to interest in modeling new borehole heat exchanger designs. These heat exchangers are environment-friendly because they inject all the geofluid back into the reservoir after harvesting its energy, resulting in zero mass withdrawal from the system. This study develops reduced-order reservoir models for quickly estimating production temperature and thermal recovery from borehole heat exchangers using inspectional analysis and predictive modeling. An inspectional analysis suggests that there are nineteen dimensionless numbers necessary to fully scale this design. These dimensionless numbers were used in the statistical modeling. A Box–Behnken experimental design was …


Chaucer's Divided "I": Narrative Voice And Performance Dynamics In Late Fourteenth-Century English Literature, Isaac Mcduffie Dec 2017

Chaucer's Divided "I": Narrative Voice And Performance Dynamics In Late Fourteenth-Century English Literature, Isaac Mcduffie

LSU Doctoral Dissertations

Throughout the twentieth century, various Chaucer scholars have worked to achieve the now-consensus opinion that Chaucer wrote his works expecting them to be both listened to within a group setting and read privately in an individual setting. These scholars have either assumed or expressly stated that the experience of listening to and reading Chaucer’s works would have been the same. This dissertation argues otherwise. I show that in the late fourteenth century, English vernacular was only starting to be understood as a written language, and this peculiar circumstance created tensions between both listening and reading modes of reception. Such tensions …


Upper Bounds On Secret-Key Agreement Over Lossy Thermal Bosonic Channels, Eneet Kaur, Mark M. Wilde Dec 2017

Upper Bounds On Secret-Key Agreement Over Lossy Thermal Bosonic Channels, Eneet Kaur, Mark M. Wilde

Faculty Publications

Upper bounds on the secret-key-agreement capacity of a quantum channel serve as a way to assess the performance of practical quantum-key-distribution protocols conducted over that channel. In particular, if a protocol employs a quantum repeater, achieving secret-key rates exceeding these upper bounds is evidence of having a working quantum repeater. In this paper, we extend a recent advance [Liuzzo-Scorpo, Phys. Rev. Lett. 119, 120503 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.120503] in the theory of the teleportation simulation of single-mode phase-insensitive Gaussian channels such that it now applies to the relative entropy of entanglement measure. As a consequence of this extension, we find tighter upper bounds …


Exploring The Origins Of The Dzyaloshinskii-Moriya Interaction In Mnsi, C. Dhital, L. Debeer-Schmitt, Q. Zhang, W. Xie, D. P. Young, J. F. Ditusa Dec 2017

Exploring The Origins Of The Dzyaloshinskii-Moriya Interaction In Mnsi, C. Dhital, L. Debeer-Schmitt, Q. Zhang, W. Xie, D. P. Young, J. F. Ditusa

Faculty Publications

By using magnetization and small-angle neutron scattering measurements, we have investigated the magnetic behavior of the Mn1-xIrxSi system to explore the effect of increased carrier density and spin-orbit interaction on the magnetic properties of MnSi. We determine estimates of the spin wave stiffness and the Dzyaloshinskii-Moriya (DM) interaction strength and compare with Mn1-xCoxSi and Mn1-xFexSi. Despite the large differences in atomic mass and size of the substituted elements, Mn1-xCoxSi and Mn1-xIrxSi show nearly identical variations in their magnetic properties with substitution. We find a systematic dependence of the transition temperature, the ordered moment, the helix period, and the DM interaction …


Inferences On Mass Composition And Tests Of Hadronic Interactions From 0.3 To 100 Eev Using The Water-Cherenkov Detectors Of The Pierre Auger Observatory, A. Aab, P. Abreu, M. Aglietta, I. Al Samarai, I. F.M. Albuquerque, I. Allekotte, A. Almela, J. Alvarez Castillo, J. Alvarez-Muñiz, G. A. Anastasi, L. Anchordoqui, B. Andrada, S. Andringa, C. Aramo, F. Arqueros, N. Arsene, H. Asorey, P. Assis, J. Aublin, G. Avila, A. M. Badescu, A. Balaceanu, F. Barbato, R. J. Barreira Luz, J. J. Beatty, K. H. Becker, J. A. Bellido, C. Berat, M. E. Bertaina, X. Bertou, P. L. Biermann, J. Biteau, S. G. Blaess Dec 2017

Inferences On Mass Composition And Tests Of Hadronic Interactions From 0.3 To 100 Eev Using The Water-Cherenkov Detectors Of The Pierre Auger Observatory, A. Aab, P. Abreu, M. Aglietta, I. Al Samarai, I. F.M. Albuquerque, I. Allekotte, A. Almela, J. Alvarez Castillo, J. Alvarez-Muñiz, G. A. Anastasi, L. Anchordoqui, B. Andrada, S. Andringa, C. Aramo, F. Arqueros, N. Arsene, H. Asorey, P. Assis, J. Aublin, G. Avila, A. M. Badescu, A. Balaceanu, F. Barbato, R. J. Barreira Luz, J. J. Beatty, K. H. Becker, J. A. Bellido, C. Berat, M. E. Bertaina, X. Bertou, P. L. Biermann, J. Biteau, S. G. Blaess

Faculty Publications

We present a new method for probing the hadronic interaction models at ultrahigh energy and extracting details about mass composition. This is done using the time profiles of the signals recorded with the water-Cherenkov detectors of the Pierre Auger Observatory. The profiles arise from a mix of the muon and electromagnetic components of air showers. Using the risetimes of the recorded signals, we define a new parameter, which we use to compare our observations with predictions from simulations. We find, first, inconsistencies between our data and predictions over a greater energy range and with substantially more events than in previous …


First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda Dec 2017

First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda

Faculty Publications

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars …


Characterization Of Pathogenic Vibrio Parahaemolyticus From The Chesapeake Bay, Maryland, Arlene J. Chen, Nur A. Hasan, Bradd J. Haley, Elisa Taviani, Mitch Tarnowski, Kathy Brohawn, Crystal N. Johnson, Rita R. Colwell, Anwar Huq Dec 2017

Characterization Of Pathogenic Vibrio Parahaemolyticus From The Chesapeake Bay, Maryland, Arlene J. Chen, Nur A. Hasan, Bradd J. Haley, Elisa Taviani, Mitch Tarnowski, Kathy Brohawn, Crystal N. Johnson, Rita R. Colwell, Anwar Huq

Faculty Publications

Vibrio parahaemolyticus is the leading cause of bacterial gastroenteritis associated with seafood consumption in the United States. Here we investigated the presence of virulence factors and genetic diversity of V. parahaemolyticus isolated from water, oyster, and sediment samples from the Chesapeake Bay, Maryland. Of more than 2,350 presumptive Vibrio collected, more than half were confirmed through PCR as V. parahaemolyticus, with 10 encoding both tdh and trh and 6 encoding only trh. Potentially pathogenic V. parahaemolyticus were then serotyped with O1:KUT and O3:KUT predominant. Furthermore, pulsed-field gel electrophoresis was performed and the constructed dendrogram displayed high diversity, as did results …


Boulder Distribution Analysis Of Impact Craters In The Tharsis Region And Elysium Planitia, Mars, Nicole Button Dec 2017

Boulder Distribution Analysis Of Impact Craters In The Tharsis Region And Elysium Planitia, Mars, Nicole Button

LSU Master's Theses

Crater counting is an accepted method for dating the surface of a planetary body. An older landscape will have a higher areal density of craters due to exposure of impacts occurring over a longer time period. Since each initial impact only forms one primary crater, secondary craters need to be excluded in the crater counting method to appropriately catalog only distinct impact events. However, small primary craters may be difficult to distinguish from secondary craters. Understanding physical features of impact craters, such as the ejecta blanket, would improve the planetary community’s ability to differentiate between the two types of craters. …


Characterizations Of Some Classes Of Graphs That Are Nearly Series-Parallel, Victoria Fontaine Dec 2017

Characterizations Of Some Classes Of Graphs That Are Nearly Series-Parallel, Victoria Fontaine

LSU Doctoral Dissertations

A series-parallel graph can be built from a single-edge graph by a sequence of series and parallel extensions. The class of such graphs coincides with the class of graphs that do not have the complete graph K4 as a minor. This dissertation considers a class M1 of graphs that are close to being series-parallel. In particular, every member of the class has the property that one can obtain a series-parallel graph by adding a new edge and contracting it out, or by splitting a vertex into two vertices whose neighbor sets partition the neighbor set of the original …


Erratum: First Search For Gravitational Waves From Known Pulsars With Advanced Ligo (Astrophysical Journal (2017) 839 (12) Doi: 10.3847/1538-4357/Aa677f), B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, A. Allocca, P. A. Altin, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Appert, K. Arai, M. C. Araya, J. S. Areeda, N. Arnaud, K. G. Arun, S. Ascenzi, G. Ashton Dec 2017

Erratum: First Search For Gravitational Waves From Known Pulsars With Advanced Ligo (Astrophysical Journal (2017) 839 (12) Doi: 10.3847/1538-4357/Aa677f), B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, A. Allocca, P. A. Altin, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Appert, K. Arai, M. C. Araya, J. S. Areeda, N. Arnaud, K. G. Arun, S. Ascenzi, G. Ashton

Faculty Publications

There is an error in Equation?(4) of the original paper, which should instead be (Formula Presented) This makes it consistent with Equation?(3) of Aasi et al. (2014), which was actually used when calculating the value of the Q22 upper limits from the h0 upper limits for the results of this paper.


Multi-Hazard Performance Assessment Of High-Rise Buildings, Jad El Khoury Antoun Dec 2017

Multi-Hazard Performance Assessment Of High-Rise Buildings, Jad El Khoury Antoun

LSU Master's Theses

In the last few decades, there has been an important increase in building high-rise constructions in many cities around the world. Since they offer several benefits in populous areas in terms of space efficiency, economy and sustainability, tower buildings attracted practitioners and researchers to understand better their exclusive behavior and response to natural hazards (e.g., hurricanes, earthquakes). Because of their flexibility and their commonly limited damping, skyscrapers are more susceptible to wind and earthquake actions than low- and mid-rise buildings. Moreover, many locations are prone to multiple hazards; hence, it is important to understand thoroughly the structural behavior of structures …


Dinoflagellate Cysts Track Eutrophication In The Northern Gulf Of Mexico, Andrea M. Price, Melissa M. Baustian, R. Eugene Turner, Nancy N. Rabalais, Gail L. Chmura Dec 2017

Dinoflagellate Cysts Track Eutrophication In The Northern Gulf Of Mexico, Andrea M. Price, Melissa M. Baustian, R. Eugene Turner, Nancy N. Rabalais, Gail L. Chmura

Faculty Publications

We examined organic-walled dinoflagellate cysts from one 210Pb-dated sediment core and 39 surface sediment samples from the northern Gulf of Mexico to determine the relationship between nutrient enrichment and cyst assemblages in this region characterized by oxygen deficiency. The core spans from 1962 to 1997 and its sampling location is directly influenced by the Mississippi River plume. Surface sediments were collected in 2006, 2007, 2008, and 2014 and represent approximately 1 to 4 years of accumulation. A total of 57 cyst taxa were recorded, and four heterotrophic taxa in particular were found to increase in the top section (1986–1997) of …


Polyamorphic Transformations In Fe-Ni-C Liquids: Implications For Chemical Evolution Of Terrestrial Planets, Xiaojing Lai, Bin Chen, Jianwei Wang, Yoshio Kono, Feng Zhu Dec 2017

Polyamorphic Transformations In Fe-Ni-C Liquids: Implications For Chemical Evolution Of Terrestrial Planets, Xiaojing Lai, Bin Chen, Jianwei Wang, Yoshio Kono, Feng Zhu

Faculty Publications

©2017. American Geophysical Union. All Rights Reserved. During the formation of the Earth's core, the segregation of metallic liquids from silicate mantle should have left behind evident geochemical imprints on both the mantle and the core. Some distinctive geochemical signatures of the mantle-derived rocks likely own their origin to the metal-silicate differentiation of the primitive Earth, setting our planet apart from undifferentiated meteorites as well as terrestrial planets or moons isotopically and compositionally. Understanding the chemical evolution of terrestrial planetary bodies requires knowledge on properties of both liquid iron alloys and silicates equilibrating under physicochemical conditions pertinent to the deep …


Comparison Of Five Methods For Parameter Estimation Under Taylor's Power Law, Peijian Shi, David A. Ratkowsky, Ningtao Wang, Yang Li, Lei Zhao, Gadi V.P. Reddy, Bai Lian Li Dec 2017

Comparison Of Five Methods For Parameter Estimation Under Taylor's Power Law, Peijian Shi, David A. Ratkowsky, Ningtao Wang, Yang Li, Lei Zhao, Gadi V.P. Reddy, Bai Lian Li

Faculty Publications

Taylor's power law (TPL) can be applied to the mean-variance relationship for various quantities, e.g., population densities over space and time, biomass of plants in the growth processes, developmental rates and growth rates of arthropods at different temperatures, etc. When TPL holds in the grouped data (e.g., the biomass of plants at different investigation times with limited replicates at each investigation), we must consider the heterocedasticity when carrying out the parameter estimation for a given mathematical model. We propose two new target functions based on TPL and attempt to more accurately estimate the model parameter(s). By capturing the mean-variance relationship, …


Mechanical Specific Energy Versus Depth Of Cut In Rock Cutting And Drilling, Yaneng Zhou, Wu Zhang, Isaac Gamwo, Jeen Shang Lin Dec 2017

Mechanical Specific Energy Versus Depth Of Cut In Rock Cutting And Drilling, Yaneng Zhou, Wu Zhang, Isaac Gamwo, Jeen Shang Lin

Faculty Publications

The relationship between Mechanical Specific Energy (MSE) and the Rate of Penetration (ROP), or equivalently the depth of cut per revolution, provides an important measure for strategizing a drilling operation. This study explores how MSE evolves with depth of cut, and presents a concerted effort that encompasses analytical, computational and experimental approaches. A simple model for the relationship between MSE and cutting depth is first derived with consideration of the wear progression of a circular cutter. This is an extension of Detournay and Defourny's phenomenological cutting model. Wear is modeled as a flat contact area at the bottom of a …


Numerical Analysis Of Downhole Heat Exchanger Designed For Geothermal Energy Production, I. Akhmadullin, M. Tyagi Dec 2017

Numerical Analysis Of Downhole Heat Exchanger Designed For Geothermal Energy Production, I. Akhmadullin, M. Tyagi

Faculty Publications

A traditional way of geothermal energy production implies hot brine extraction from the reservoir to a surface facility. This method is economically profitable only for high enthalpy reservoirs associated with shallow depths and high temperatures. The low enthalpy geothermal (LEG) projects are out of consideration due to the high cost of produced electric power related to expensive drilling, cost of the binary cycle system, and long term installation cost. This paper presents a new zero mass extraction method utilizing downhole heat exchanger (DHE) with no geo-fluid production to the surface. The well design stays as a single horizontal well with …


A Study Of The Urban Red Fox (Vulpes Vulpes) Population In Baton Rouge, Louisiana Using Social Media, Ahsennur Soysal Nov 2017

A Study Of The Urban Red Fox (Vulpes Vulpes) Population In Baton Rouge, Louisiana Using Social Media, Ahsennur Soysal

LSU Master's Theses

Foxes are timid yet resourceful animals that are integrated into many urban environments. Because they are elusive, collecting information about the number of urban foxes, their diet and spatial distribution, their interactions with the ecological community in their urban habitat, as well as residents’ response to them, is difficult. Involving stakeholders to participate in the data collection on wildlife via citizen science on social media is one way to overcome this complication, while simultaneously engaging residents in the ecology happening around them. Therefore, we used social media as the platform to engage the public to document and map the foxes …


Scaling Relationships Between Cranial Morphological Features And Cranial Capacity In Modern Humans, Jacob Jesch Nov 2017

Scaling Relationships Between Cranial Morphological Features And Cranial Capacity In Modern Humans, Jacob Jesch

LSU Master's Theses

Certain cranial morphologies referred to here as “cranial predictor features” are known to allometrically scale with body mass at statistically significant levels. Brain size likewise is known to scale with body mass, with brain-to-body-mass ratio being expressed numerically via the encephalization quotient. The study at hand aims to demonstrate whether brain size via its skeletal proxy of cranial capacity also scales with cranial predictor features. Correlation analysis was employed on two samples of contemporary male and female modern humans, respectively, in order to determine the statistical significance and degree of association between cranial predictor features and cranial capacity, as well …


Nonlinear Model-Based Control For Neuromuscular Electrical Stimulation, Ruzhou Yang Nov 2017

Nonlinear Model-Based Control For Neuromuscular Electrical Stimulation, Ruzhou Yang

LSU Doctoral Dissertations

Neuromuscular electrical stimulation (NMES) is a technology where skeletal muscles are externally stimulated by electrodes to help restore functionality to human limbs with motor neuron disorder. This dissertation is concerned with the model-based feedback control of the NMES quadriceps muscle group-knee joint dynamics. A class of nonlinear controllers is presented based on various levels of model structures and uncertainties. The two main control techniques used throughout this work are backstepping control and Lyapunov stability theory.

In the first control strategy, we design a model-based nonlinear control law for the system with the exactly known passive mechanical that ensures asymptotical tracking. …


Development Of Remote Hydroxylation Via Redox Catalysis And Mild Activation Of Thioglycosides For O-Glycosylation, Kristina Deveaux Nov 2017

Development Of Remote Hydroxylation Via Redox Catalysis And Mild Activation Of Thioglycosides For O-Glycosylation, Kristina Deveaux

LSU Doctoral Dissertations

The focus of this dissertation is the development of a C-H functionalization method using redox catalysis and the synthesis of saccharides using thioglycosides. Chapter 1 is a review of C-H functionalization and visible-light photoredox catalysis. Over the years there have been many significant contributions to the field of C-H functionalization. Select examples have been discussed and a foundation for the method developed in chapter 2 has been outlined. Chapter 2 discusses the development and optimization of a C-H functionalization method. This approach uses the Tzo directing group and Ir(ppy)3 to activate a remote C-H bond via 1,6- and …


Multimode Approach To Classical And Quantum Diffraction, Zhihao Xiao Nov 2017

Multimode Approach To Classical And Quantum Diffraction, Zhihao Xiao

LSU Doctoral Dissertations

I have investigated classical diffraction of optical beams with multimode approach, which is a significant improvement upon the traditional Huygens–Fresnel principle based diffraction theory. I have also investigated quantum diffraction with multimode approach, which describes the behavior of multimode quantum state. Multimode approach to classical and quantum diffraction provides a clear mathematical formalism and is verified by numerical simulations. In addition, I present the work on superconducting qubit and oscillator with time-dependent coupling coefficient, with first order correction with finite qubit energy and schemes based on and π pulses.