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Lsu General Catalog 2023-2024, Louisiana State University And Agricultural And Mechanical College

LSU General Catalog

The LSU General Catalog describes all undergraduate and graduate departments and programs with degree requirements and courses offered for each one. The LSU General Catalog includes information on registration and financial aid as well as academic services offered to all students.

A Finite Element Method For A Two-Dimensional Pucci Equation, Susanne C. Brenner, Li Yeng Sung, Zhiyu Tan

Faculty Publications

A nonlinear least-squares finite element method for strong solutions of the Dirichlet boundary value problem of a two-dimensional Pucci equation on convex polygonal domains is investigated in this paper. We obtain a priori and a posteriori error estimates and present corroborating numerical results, where the discrete nonsmooth and nonlinear optimization problems are solved by an active set method and an alternating direction method with multipliers.

An Interior Maximum Norm Error Estimate For The Symmetric Interior Penalty Method On Planar Polygonal Domains, Susanne C. Brenner, Li Yeng Sung

Faculty Publications

We establish an interior maximum norm error estimate for the symmetric interior penalty method on planar polygonal domains.

A Geometric Trapping Approach To Global Regularity For 2d Navier-Stokes On Manifolds, Aynur Bulut, Manh Khang Huynh

Faculty Publications

In this paper, we use frequency decomposition techniques to give a direct proof of global existence and regularity for the Navier-Stokes equations on two-dimensional Riemannian manifolds without boundary. Our techniques are inspired by an approach of Mattingly and Sinai [15] which was developed in the context of periodic boundary conditions on a flat background, and which is based on a maximum principle for Fourier coefficients. The extension to general manifolds requires several new ideas, connected to the less favorable spectral localization properties in our setting. Our arguments make use of frequency projection operators, multilinear estimates that originated in the study …

Right-Angled Coxeter Groups With Non-Planar Boundary, Pallavi Dani, Matthew Haulmark, Genevieve Walsh

Faculty Publications

We investigate the planarity of the boundaries of right-angled Coxeter groups. We show that non-planarity of the defining graph does not necessarily imply non-planarity of every boundary of the associated right-angled Coxeter group, although it does in many cases. Our techniques yield a characterization of the triangle-free defining graphs such that the associated right-angled Coxeter group has boundary a Menger curve.

Unavoidable Induced Subgraphs Of Large 2-Connected Graphs, Sarah Allred, Guoli Ding, Bogdan Oporowski

Faculty Publications

Ramsey_ proved that for every positive integer n, every sufficiently large graph contains an induced Kn or Kn. Among the many extensions of Ramsey's theorem, there is an analogue for connected graphs: For every positive integer n, every sufficiently large connected graph contains an induced Kn, K1,n, or Pn. In this paper, we establish an analogue for 2-connected graphs. In particular, we prove that for every integer exceeding two, every sufficiently large 2-connected graph contains one of the following as an induced subgraph: Kn, a subdivision of K2,n, a subdivision of K2,n with an edge between the two vertices of …

On Gupta's Codensity Conjecture, Yan Cao, Guantao Chen, Guoli Ding, Guangming Jing, Wenan Zang

Faculty Publications

Let G = (V, E) be a multigraph. The cover index ξ (G) of G is the greatest integer k for which there is a coloring of E with k colors such that each vertex of G is incident with at least one edge of each color. Let δ (G) be the minimum degree of G, and let Φ (G) be the codensity of G, defined by Φ (G) = min (equation presented) {^2|E+(U)||U|+1 : U ⊆ V, | U| ≥ 3 and odd }, where E⁺(U) is the set of all edges of G with …

Part I — Introduction: Social Physics And The Vespace Project, Jeffrey M. Leichman, Ben Samuel

Faculty Publications

This article introduces the VESPACE project, an international, multi-disciplinary digital humanities initiative to build a computer-mediated playable simulation—a video game—of the eighteenth-century Paris Fair theatre. As part of this project, a weeklong postgraduate workshop was convened by the authors in May 2020 to develop protocols and procedures for coding literary and historical data for the Ensemble social physics engine that will govern behaviour of non-player characters (NPCs) in the interactive model. This article lays out the history and theory of social physics, the potential impacts of this project on historiographic practice, and the methodology and outcomes of the workshop week. …

Exploring The Spatial Autocorrelation In Soil Moisture Networks: Analysis Of The Bias From Upscaling The Texas Soil Observation Network (Txson), Yaping Xu, Cuiling Liu, Lei Wang, Lei Zou

Faculty Publications

Microwave remote sensing such as soil moisture active passive (SMAP) can provide soil moisture data for agricultural and hydrological studies. However, the scales between station-measured and satellite-measured products are quite different, as stations measure on a point scale while satellites have a much larger footprint (e.g., 9 km). Consequently, the validation for soil moisture products, especially inter-comparison between these two types of observations, is quite a challenge. Spatial autocorrelation among the stations could be a contribution of bias, which impacts the dense soil moisture networks when compared with satellite soil moisture products. To examine the effects of spatial autocorrelation to …

Planetary Protection: An International Concern And Responsibility, Athena Coustenis, Niklas Hedman, Peter T. Doran, Omar Al Shehhi, Eleonora Ammannito, Masaki Fujimoto, Olivier Grasset, Frank Groen, Alexander G. Hayes, Vyacheslav Ilyin, K. Praveen Kumar, Caroline Emmanuelle Morisset, Christian Mustin, Karen Olsson-Francis, Jing Peng, Olga Prieto-Ballesteros, Francois Raulin, Petra Rettberg, Silvio Sinibaldi, Yohey Suzuki, Kanyan Xu, Maxim Zaitsev

Faculty Publications

Planetary protection is a set of measures agreed upon at an international level to ensure the protection of scientific investigation during space exploration. As space becomes more accessible with traditional and new actors launching complex and innovative projects that involve robotics (including sample return) and human exploration, we have the responsibility to protect the pristine environments that we explore and our own biosphere. In this sense, the Committee on Space Research (COSPAR) provides the international standard for planetary protection as well as a forum for international consultation. COSPAR has formulated a Planetary Protection Policy with associated requirements for responsible space …

Learning Infused Quantum-Classical Distributed Optimization Technique For Power Generation Scheduling, Reza Mahroo, Amin Kargarian

Faculty Publications

The advent of quantum computing can potentially revolutionize how complex problems are solved. This article proposes a two-loop quantum-classical solution algorithm for generation scheduling by infusing quantum computing, machine learning, and distributed optimization. The aim is to facilitate employing noisy near-term quantum machines with a limited number of qubits to solve practical power system optimization problems, such as generation scheduling. The outer loop is a three-block quantum alternating direction method of multipliers (QADMM) algorithm that decomposes the generation scheduling problem into three subproblems, including one quadratically unconstrained binary optimization (QUBO) and two non-QUBOs. The inner loop is a trainable quantum …

Interfacial Activity And Surface Pka Of Perfluoroalkyl Carboxylic Acids (Pfcas), Ruchi Patel, Luis E. Saab, Philip J. Brahana, Kalliat T. Valsaraj, Bhuvnesh Bharti

Faculty Publications

Perfluoroalkyl carboxylic acids (PFCAs) are widely used synthetic chemicals that are known for their exceptional stability and interfacial activity. Despite their industrial and environmental significance, discrepancies exist in the reported pKa values for PFCAs, often spanning three to four units. These disparities stem from an incomplete understanding of how pH influences the ionized state of PFCA molecules in the bulk solution and at the air-water interface. Using pH titration and surface tension measurements, we show that the pKa values of the PFCAs adsorbed at the air-water interface differ from the bulk. Below the equivalence point, the undissociated and dissociated forms …

Editorial: Application Of Periodic Structure Theory With Finite Element Approach, Chitaranjan Pany, Guoqiang Li

Faculty Publications

No abstract provided.

Toward The Development Of Plasticity Theories For Application To Small-Scale Metal Structures, Bin Zhang, K. L. Nielsen, J. W. Hutchinson, W. J. Meng

Faculty Publications

Experiments are performed on micron-scale single-crystal prototypical structural elements experiencing combined torsion and bending to gather data on their load-carrying capacity in the range of size and strain relevant to micron-scale structures for which little data are available. The observed strengthening dependence on size for the structural elements is in general accord with trends inferred from prior tests such as indentation and pure torsion. In addition, the experiments systematically reveal the strengthening size-dependence of structural elements whose surface has been passivated by a very thin Cr coating, an effect shown to have substantial strengthening potential. A state-of-the-art strain gradient plasticity …

Optimizing Pier Design To Mitigate Scour: A Comprehensive Review And Large Eddy Simulation Study, A. M. Aly, F. Khaled

Faculty Publications

Scour-induced sediment erosion poses a significant threat to the safety and longevity of infrastructure, including bridges, wind turbines, elevated buildings, and coastal infrastructure. Despite the well-known destructive consequences of scour, accurate models that capture the complexity of its dynamics remain elusive, impeding the development of effective countermeasures. We provide a comprehensive review of existing literature on scour dynamics and examine the fluid dynamics and bed shear stress surrounding bridge piers. We propose CFD (Computational Fluid Dynamics) simulations with LES (Large-Eddy Simulation). The current paper demonstrate that LES is a more effective technique than RANS (Reynolds averaged Navier-Stokes) for investigating bridge …

Semi-Parametric Control Architecture For Autonomous Underwater Vehicles Subject To Time Delays, Ignacio Carlucho, Dylan Stephens, William Ard, Corina Barbalata

Faculty Publications

This paper presents a data-driven model-based control system for autonomous underwater vehicles (or AUVs) subject to input delays. This work is motivated by the input time delays that can arise in underwater robotics due to communication restrictions and sensor malfunctions. Such delays can highly degrade the performance of classical control structures resulting in unpredictable system behaviours. The proposed control architecture addresses such limitations. The approach incorporates a linear dynamic representation of the system obtained using the Koopman operator in an observer/state prediction formulation. The proposed control architecture is designed based on discrepancies between the data-driven estimation of the system's behaviour …

Event-Triggered Control Under Unknown Input And Unknown Measurement Delays Using Interval Observers, Michael Malisoff, Frederic Mazenc, Corina Barbalata

Faculty Publications

We provide a new input-to-state stabilizing event-triggered feedback design for linear systems with unknown input delays, unknown measurement delays, and unknown additive disturbances. Our trigger times are computed using only the matrices defining the system and time-lagged sampled state values. We use the theory of positive systems, interval observers, and a vector version of Halanay's inequality. We illustrate our method using a marine robotic model.

Analytical Advances In Homeowner Flood Risk Quantification Considering Insurance, Building Replacement Value, And Freeboard, Md Adilur Rahim, Rubayet Bin Mostafiz, Carol J. Friedland, Robert V. Rohli, Nazla Bushra

Faculty Publications

An accurate economic loss assessment for natural hazards is vital for planning, mitigation, and actuarial purposes. The widespread and costly nature of flood hazards, with the economically disadvantaged disproportionately victimized population, makes flood risk assessment particularly important. Here, flood risk is assessed as incurred by the homeowner vs. the flood insurer for insured U.S. properties through the derivation of average annual loss (AAL). AAL is estimated and partitioned using Monte Carlo simulation at the individual home scale, considering insurance coverage and deductible, and the first-floor height (i.e., height of the first floor above the ground), to determine the AAL proportion …

Flood Damage And Shutdown Times For Industrial Process Facilities: A Vulnerability Assessment Process Framework, Carol J. Friedland, Fatemeh Orooji, Ayat Al Assi, Matthew L. Flynn, Rubayet Bin Mostafiz

Faculty Publications

Much of the U.S. petrochemical infrastructure is heavily concentrated along the western coast of the Gulf of Mexico within the impact zone of major tropical cyclone events. Flood impacts of recent tropical disturbances have been exacerbated by an overall lack of recognition of the vulnerabilities to process systems from water intrusion, as well as insufficient disaster mitigation planning. Vulnerability assessment methods currently call for the aggregation of qualitative data to survey the susceptibility of industrial systems to floodwater damage. A means to quantify these consequences is less often employed, resulting in a poor translation of the threat of flood hazards …

Homeowner Flood Risk And Risk Reduction From Home Elevation Between The Limits Of The 100- And 500-Year Floodplains, Ayat Al Assi, Rubayet Bin Mostafiz, Carol J. Friedland, Robert V. Rohli, Md Adilur Rahim

Faculty Publications

Floods inflict significant damage even outside the 100-year floodplain. Thus, restricting flood risk analysis to the 100-year floodplain (Special Flood Hazard Area (SFHA) in the United States of America) is misleading. Flood risk outside the SFHA is often underestimated because of minimal flood-related insurance requirements and regulations and sparse flood depth data. This study proposes a systematic approach to predict flood risk for a single-family home using average annual loss (AAL) in the shaded X Zone–the area immediately outside the SFHA (i.e., the 500-year floodplain), which lies between the limits of the 1.0- and 0.2-percent annual flood probability. To further …

A Lagrangian Particle Model With Nesting Capability And Its Application To The Modeling Of Plastics In The Gulf Of Mexico, Weiyuan Dong

LSU Master's Theses

In our study, we refined an offline three-dimensional (3D) Lagrangian model named the Larval TRANSport Lagrangian (LTRANS) model and applied it to the Gulf of Mexico (GOM). Previous research that applied the model within the Texas-Louisiana (TXLA) shelf domain, which released plastics to simulate their trajectories and fate, showed that more than 40% of simulated particles did not reach the land boundaries. Some of those particles were assumed to move out of the TXLA domain. In reality, these particles could also re-enter the TXLA domain due to processes such as tidal excursion, mesoscale eddies and inertial oscillation. However, the model …

Runge-Kutta Methods For Rough Differential Equations, Martin Redmann, Sebastian Riedel

Journal of Stochastic Analysis

No abstract provided.

A Jump-Diffusion Process For Asset Price With Non-Independent Jumps, Yihren Wu, Majnu John

Journal of Stochastic Analysis

No abstract provided.

Light-Weight Structural Optimization Through Biomimicry, Machine Learning, And Inverse Design, Adithya Challapalli

LSU Doctoral Dissertations

In load-bearing lightweight architectures, cellular materials were frequently utilized. While octahedron, tetrahedron, and octet truss lattice truss were built for lightweight architectures with stretching and flexural dominance, it can be believed that new cells could easily be designed that might perform much better than the present ones in terms of mechanical and architectural characteristics. Machine learning-based structure scouting and design improvisation for better mechanical performance is a growing field of study. Additionally, biomimicry—the science of imitating nature’s elements—offers people a wealth of resources from which to draw motivation as they work to create a better quality of life.

Here, utilizing …

Application Of Distributed Fiber-Optic Sensing For Pressure Predictions And Multiphase Flow Characterization, Gerald Kelechi Ekechukwu

LSU Doctoral Dissertations

In the oil and gas industry, distributed fiber optics sensing (DFOS) has the potential to revolutionize well and reservoir surveillance applications. Using fiber optic sensors is becoming increasingly common because of its chemically passive and non-magnetic interference properties, the possibility of flexible installations that could be behind the casing, on the tubing, or run on wireline, as well as the potential for densely distributed measurements along the entire length of the fiber. The main objectives of my research are to develop and demonstrate novel signal processing and machine learning computational techniques and workflows on DFOS data for a variety of …

Quantization Of The Monotone Poisson Central Limit Theorem, Yungang Lu

Journal of Stochastic Analysis

No abstract provided.

A Very Luminous Jet From The Disruption Of A Star By A Massive Black Hole, Igor Andreoni, Michael W. Coughlin, Daniel A. Perley, Yuhan Yao, Wenbin Lu, S. Bradley Cenko, Harsh Kumar, Shreya Anand, Anna Y.Q. Ho, Mansi M. Kasliwal, Antonio De Ugarte Postigo, Ana Sagués-Carracedo, Steve Schulze, D. Alexander Kann, S. R. Kulkarni, Jesper Sollerman, Nial Tanvir, Armin Rest, Luca Izzo, Jean J. Somalwar, David L. Kaplan, Tomás Ahumada, G. C. Anupama, Katie Auchettl, Sudhanshu Barway, Eric C. Bellm, Varun Bhalerao, Joshua S. Bloom, Michael Bremer, Mattia Bulla, Eric Burns, Sergio Campana, Poonam Chandra

Faculty Publications

Tidal disruption events (TDEs) are bursts of electromagnetic energy that are released when supermassive black holes at the centres of galaxies violently disrupt a star that passes too close¹. TDEs provide a window through which to study accretion onto supermassive black holes; in some rare cases, this accretion leads to launching of a relativistic jet^2–9, but the necessary conditions are not fully understood. The best-studied jetted TDE so far is Swift J1644+57, which was discovered in γ-rays, but was too obscured by dust to be seen at optical wavelengths. Here we report the optical detection of …

Pnp Maxtools: Autonomous Parameter Control In Maxmsp Utilizing Mir Algorithms, Austin Alexander Franklin

LSU Doctoral Dissertations

This research presents a new approach to computer automation through the implementation of novel real-time music information retrieval algorithms developed for this project. It documents the development of the PnP.Maxtools package, a set of open source objects designed within the popular programming environment MaxMSP. The package is a set of pre/post processing filters, objective and subjective timbral descriptors, audio effects, and other objects that are designed to be used together to compose music or improvise without the use of external controllers or hardware. The PnP.Maxtools package objects are designed to be used quickly and easily using a `plug and play' …

From Mapping Place To Mapping Space In Library Gis Work, Lena Denis

Journal of Critical Digital Librarianship

At many academic libraries, library workers run the teaching, general reference consultations, technical troubleshooting, and software and licensing maintenance in Geographic Information Systems (GIS) for their institutions. This is very much the case in the Data Services unit of Johns Hopkins University’s Sheridan Libraries, where staff receive requests for help with a wide variety of mapping projects every semester. Sometimes they are straightforward requests for technical assistance, but sometimes they underpin much deeper investigations into how to situate people and significant events through time and geographic settings. This article discusses these types of requests in the context of the philosophical …

Applications Of A Superposed Ornstein-Uhlenbeck Type Processes, Santatriniaina Avotra Randrianambinina, Julius Esunge

Journal of Stochastic Analysis

No abstract provided.