Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 270

Full-Text Articles in Entire DC Network

Wavelet Compression As An Observational Operator In Data Assimilation Systems For Sea Surface Temperature, Bradley J. Sciacca Dec 2023

Wavelet Compression As An Observational Operator In Data Assimilation Systems For Sea Surface Temperature, Bradley J. Sciacca

University of New Orleans Theses and Dissertations

The ocean remains severely under-observed, in part due to its sheer size. Containing nearly billion of water with most of the subsurface being invisible because water is extremely difficult to penetrate using electromagnetic radiation, as is typically used by satellite measuring instruments. For this reason, most observations of the ocean have very low spatial-temporal coverage to get a broad capture of the ocean’s features. However, recent “dense but patchy” data have increased the availability of high-resolution – low spatial coverage observations. These novel data sets have motivated research into multi-scale data assimilation methods. Here, we demonstrate a new assimilation approach …


Measuring The Lengths Of Sperm Whales Of The Northern Gulf Of Mexico By Wavelet Analysis Of Their Usual Clicks, George Drouant Dec 2023

Measuring The Lengths Of Sperm Whales Of The Northern Gulf Of Mexico By Wavelet Analysis Of Their Usual Clicks, George Drouant

University of New Orleans Theses and Dissertations

Abstract

Acoustic recordings of underwater sounds produced by marine mammals present an attractive alternative to costly and logistically complex ship based visual surveys for collecting population data for various species.

The first reported use of underwater acoustic recordings in the long-term monitoring of sperm whale populations was by Ackleh et al. (Ackleh et al., 2012). The paper describes counting sperm whale clicks at different locations to track population changes over time.

Analysis of sperm whale clicks offers additional insight into sperm whale populations. The echo location clicks (usual clicks) of sperm whales can be used to give an estimate of …


Analysis Of Forensic Artifacts In Database Memory Using Support Vector Machine, Mahfuzul I. Nissan Dec 2022

Analysis Of Forensic Artifacts In Database Memory Using Support Vector Machine, Mahfuzul I. Nissan

University of New Orleans Theses and Dissertations

Memory analysis allows forensic investigators to establish a more complete timeline of system activity using a snapshot of main memory (i.e., RAM). Investigators may rely on such analysis to detect malicious activity and understand the scope of what data was exfiltrated. This is of particular interest in the presence of incomplete or untrusted logs, where a privileged user (or an attacker with such capabilities) can altogether bypass or disable logging. In such instances, a forensic investigator can still rely on the fact that data must ultimately be processed in memory, regardless of the information that is recorded in audit logs. …


Photoproducts And Transformations Of Organic Pollutants In Aquatic Environments, Elizabeth Whisenhant Dec 2022

Photoproducts And Transformations Of Organic Pollutants In Aquatic Environments, Elizabeth Whisenhant

University of New Orleans Theses and Dissertations

The degradation of petroleum-derived organic pollutants in aquatic systems occurs through lengthened exposure to UV and visible light. In this thesis, organic pollutants include crude oil, refined fuels, and plastic particles or films. The photo-oxidation of these pollutants are monitored over natural waters. To characterize the molecular signatures of photo-oxidized petroleum, bench-scale spills of refined fuels and crude oil were irradiated over Alaskan waters. A 4-component fluorescence PARAFAC model revealed a unique feature associated with photo-oxidized refined fuel unlike traditional “microbial”- or “terrestrial-like” components. In contrast, crude oil photolytically decomposed into humic-like components and oxidized aliphatics. FT-ICR MS data corroborated …


Tools For Predicting Emulsification Capacity Of Crude Oil Exposed To Sunlight: Impact Of Photoproduced Carboxylic Acids On Emulsion Stability, Chaka Nacaya Brown Dec 2022

Tools For Predicting Emulsification Capacity Of Crude Oil Exposed To Sunlight: Impact Of Photoproduced Carboxylic Acids On Emulsion Stability, Chaka Nacaya Brown

University of New Orleans Theses and Dissertations

The role of acids in the formation of emulsions from sunlight exposed petroleum is not well understood. To elucidate the impact of sunlight on the formation of emulsions from petroleum, Macondo, its surrogate and NIST 1619b and 2717a were separately exposed to simulated sunlight for up to 48 hours as a film dispersed into a quartz dish, or a film spread on water. Emulsion stability was scored from 0-5. All exposures demonstrated a correlation between emulsion stability and sunlight exposure with no observable emulsification in absence of photoproduction due to sunlight exposure. Aqueous studies of DOCHC (dissolved organic carbon …


Denoising And Deconvolving Sperm Whale Data In The Northern Gulf Of Mexico Using Fourier And Wavelet Techniques, Kendal Mccain Leftwich Dec 2022

Denoising And Deconvolving Sperm Whale Data In The Northern Gulf Of Mexico Using Fourier And Wavelet Techniques, Kendal Mccain Leftwich

University of New Orleans Theses and Dissertations

The use of underwater acoustics can be an important component in obtaining information from the oceans of the world. It is desirable (but difficult) to compile an acoustic catalog of sounds emitted by various underwater objects to complement optical catalogs. For example, the current visual catalog for whale tail flukes of large marine mammals (whales) can identify even individual whales from their individual fluke characteristics. However, since sperm whales, Physeter microcephalus, do not fluke up when they dive, they cannot be identified in this manner. A corresponding acoustic catalog for sperm whale clicks could be compiled to identify individual …


Synthesis And Electrochemical Characterization Of Alkali Metal Borides As Redox Active Anion Frameworks, Michael R. Shabetai Dec 2022

Synthesis And Electrochemical Characterization Of Alkali Metal Borides As Redox Active Anion Frameworks, Michael R. Shabetai

University of New Orleans Theses and Dissertations

Redox activity in intercalation cathodes is commonly attributed to changes in oxidation states of transition metal ions. Recently, a growing body of evidence revealed that the redox activity of oxygen contributes to the capacity of some known cathodes. We focused on designing an oxygen free intercalation cathode with redox-active anions. In order to overcome the entropic driving force for the decomposition of a charged redox active anion cathode, we looked for chemistries with solid (no gases) possible decomposition products. Additionally, the involvement of anions in a network of covalent bonds with shared electrons was considered as a possible way for …


Phosphate Mineralogy And Paragenesis Of The Fletcher Pegmatite, North Groton, New Hampshire, Susanna T. Kreinik Dec 2022

Phosphate Mineralogy And Paragenesis Of The Fletcher Pegmatite, North Groton, New Hampshire, Susanna T. Kreinik

University of New Orleans Theses and Dissertations

Investigation of phosphate assemblages selectively collected at the Fletcher Mine pegmatite, North Groton, New Hampshire, yielded eighteen discrete secondary phosphate species. Secondary phases were formed via metasomatic (high temperature) and hydrothermal (low temperature) alteration of primary triphylite and fluorapatite. Mineral associations bear proximal phases known to occur under contrasting conditions, both oxidizing and reducing, suggesting the formation of microenvironments during concomitant mineral generation. Late-stage hydrothermal fluids provide ions taken up in low temperature secondary phases with calcium and magnesium most prevalent in these suites. High iron to manganese ratios in analyzed specimens establish the relative evolution of the pegmatite host. …


Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin Aug 2022

Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin

University of New Orleans Theses and Dissertations

Polyploidy, a term used to describe organisms with cells having more than two paired sets of chromosomes, is a significant driver of diversification among land plants. Over a century of research has advanced our understanding of polyploidization in some taxa, but polyploid organisms remain understudied. In this dissertation, I investigate chromosome number evolution, phylogeographic structure, genetic differentiation, and the effects of climate change on ploidy level distribution using polyploid plant systems. In the first chapter, I inferred a molecular phylogeny of Allium, an economically important genus that includes cultivated crops and ornamentals, to investigate evolutionary transitions in chromosome number …


Facies Analysis Of Terrebonne Basin Using Vibracores And Chirp Seismic Data, Joseph M. Hankerson Aug 2022

Facies Analysis Of Terrebonne Basin Using Vibracores And Chirp Seismic Data, Joseph M. Hankerson

University of New Orleans Theses and Dissertations

This study was conducted in upper and lower Madison Bay as well as Lake Boudreaux in Terrebonne basin located in southcentral Louisiana. This region is part of the recently abandoned Lafourche delta complex (0.6-0.8 kyr). Much of coastal Louisiana is comprised of formerly active delta complexes of the Mississippi River that have undergone subsequent reworking. As more restoration actions are being considered to combat land loss in coastal Louisiana, exploring the framework of a recently abandoned delta complex could aid in these plans. Utilizing core descriptions and CHIRP seismic data, facies analysis was performed to produce cross sections that display …


Protein-Protein Interaction Prediction From Language Of Biological Coding, Nayan Howladar Aug 2022

Protein-Protein Interaction Prediction From Language Of Biological Coding, Nayan Howladar

University of New Orleans Theses and Dissertations

Protein-protein interactions in a cell are essential to the characterization and performance of various fundamental biological processes. Due to the tedious, resource-expensive, and time-consuming experimental processes, computational techniques to solve protein pair interaction difficulties have emerged as an active research area in bioinformatics. This research seeks to develop an innovative machine learning-based technique that predicts the interaction of a protein pair based on carefully selected input features and exploits information-rich evolutionary information. We developed a protein-protein interaction predictor, PPILS, that leverages the evolutionary knowledge from the protein language model. We examined several distinct neural network architectures: CNN+LSTM, Transformer, Encoder-Decoder, and …


Synthesis, Derivatives, And Applications Of Structured Nanomaterials, Md Shahidul Islam Khan Aug 2022

Synthesis, Derivatives, And Applications Of Structured Nanomaterials, Md Shahidul Islam Khan

University of New Orleans Theses and Dissertations

Nanomaterials offer abundant applications not accessible in regular bulk structures. A nanotubular structure (nanoscroll or nanotube) is a 1D architecture with distinct properties varying from that of the parent material. The new structure for example provides more surface area and presents more active sites on the structure exterior, interior, or edges. In this research, different nanotubular materials were targeted including nanopeapods (NPPs), nanoscrolls (NScs), and their various derivatives.

Halloysite nanotubes (HNT) were used as pod materials to grow noble metal NPs in their lumen. The synthesis was done rapidly, within 2 minutes at 55 C. This allows the growth …


Parallel Algorithms For Scalable Graph Mining: Applications On Big Data And Machine Learning, Naw Safrin Sattar Aug 2022

Parallel Algorithms For Scalable Graph Mining: Applications On Big Data And Machine Learning, Naw Safrin Sattar

University of New Orleans Theses and Dissertations

Parallel computing plays a crucial role in processing large-scale graph data. Complex network analysis is an exciting area of research for many applications in different scientific domains e.g., sociology, biology, online media, recommendation systems and many more. Graph mining is an area of interest with diverse problems from different domains of our daily life. Due to the advancement of data and computing technologies, graph data is growing at an enormous rate, for example, the number of links in social networks is growing every millisecond. Machine/Deep learning plays a significant role for technological accomplishments to work with big data in modern …


Ocean Wave Prediction And Characterization For Intelligent Maritime Transportation, Pujan Pokhrel Aug 2022

Ocean Wave Prediction And Characterization For Intelligent Maritime Transportation, Pujan Pokhrel

University of New Orleans Theses and Dissertations

The national Earth System Prediction (ESPC) initiative aims to develop the predictions
for the next generation predictions of atmosphere, ocean, and sea-ice interactions in the scale of days to decades. This dissertation seeks to demonstrate the methods we can use to improve the ESPC models, especially the ocean prediction model. In the application side of the weather forecasts, this dissertation explores imitation learning with constraints to solve combinatorial optimization problems, focusing on the weather routing of surface vessels. Prediction of ocean waves is essential for various purposes, including vessel routing, ocean energy harvesting, agriculture, etc. Since the machine learning approaches …


State Estimation—Beyond Gaussian Filtering, Haozhan Meng May 2022

State Estimation—Beyond Gaussian Filtering, Haozhan Meng

University of New Orleans Theses and Dissertations

This dissertation considers the state estimation problems with symmetric Gaussian/asymmetric skew-Gaussian assumption under linear/nonlinear systems. It consists of three parts. The first part proposes a new recursive finite-dimensional exact density filter based on the linear skew-Gaussian system. The second part adopts a skew-symmetric representation (SSR) of distribution for nonlinear skew-Gaussian estimation. The third part gives an optimized Gauss-Hermite quadrature (GHQ) rule for numerical integration with respect to Gaussian integrals and applies it to nonlinear Gaussian filters.

We first develop a linear system model driven by skew-Gaussian processes and present the exact filter for the posterior density with fixed dimensional recursive …


Levee Seepage Identification From Aerial Images Using Machine Learning, Sofiane Benkara May 2022

Levee Seepage Identification From Aerial Images Using Machine Learning, Sofiane Benkara

University of New Orleans Theses and Dissertations

Levees protect from natural disasters that can threaten human health, infrastructure, and biological systems by protecting low-lying lands near or below sea level from flooding. However, seepage in those levees undermines their structural integrity, leading to failures. Today the United States has approximately over a hundred thousand miles of levee, many of which are reaching or have surpassed their initial design life. Given the concern, there is a need to develop reliable, rapid, and non-intrusive levee monitoring systems to detect the presence of seepage. This study explores the use of Deep Convolutional Neural Network (DCNN) integrated with Discrete Cosine Transform …


Video Games, Grief, And The Character Link System, Nam Nguyen May 2022

Video Games, Grief, And The Character Link System, Nam Nguyen

University of New Orleans Theses and Dissertations

Grief can encompass more than just the loss of real-life people. It can be felt with the loss of a pet, changes in daily structure, and even the loss of video game characters. The topic of grief related to video games and video game characters comes at a time when games as a service (GaaS) continue to increase in popularity and the phenomenon where these games also inevitably terminate service. To combat this unique form of grief, the Character LINK System was created as a tool that uses simple natural language processing (NLP) techniques to offer support to the bereaved …


Analysis Of Residual Neural Networks For Marine Mammal Classification Using Multi-Channel Spectrograms, Daniel T. Murphy Dec 2021

Analysis Of Residual Neural Networks For Marine Mammal Classification Using Multi-Channel Spectrograms, Daniel T. Murphy

University of New Orleans Theses and Dissertations

Surveys of marine mammal populations are an essential part of monitoring the welfare of these animals and their ecosystems. Marine mammal vocalizations provide a reliable method of identifying most species, but passive acoustic monitoring of underwater audio may generate large quantities of data that exceed the capacity of human classifiers. Preprocessing and machine learning techniques provide a method of automating the classification process. In this study, we explore machine learning approaches to vocalization classification using convolutional neural networks with residual learning. Optimal parameters for noise-removal, spectrographic window functions, preprocessing augmentations, and multi-channel spectrogram generation are derived through a series of …


Fine Grained Delta Front Sediment Transport, Sarah Noel Dec 2021

Fine Grained Delta Front Sediment Transport, Sarah Noel

University of New Orleans Theses and Dissertations

Insights into transformative coastal processes are unlocked though understanding sediment transport mechanisms in fine-grained delta front environments. Movement of fine-grained sediments on delta fronts is not wholly explained through advection settling models. While advection settling models generally assume deposition into a still body, numerical modeling of sediment re-entrainment suggests there may be tidal, wave, and/or non-steady hydrograph influences allowing particles to reach greater distances by altering the decelerating velocity field. This research explores both an advection settling model and a mass conservation Rouse profile model to understand the irreducible delta front processes controlling sediment deposition. Using field data collected on …


Effects Of Biological Cohesion On Wave Ripple Dynamics, Malcolm F. Cross Dec 2021

Effects Of Biological Cohesion On Wave Ripple Dynamics, Malcolm F. Cross

University of New Orleans Theses and Dissertations

In coastal environments, wave-generated oscillatory flow in the bottom boundary layer mobilizes sediment resulting in bedform generation and evolution. The presence of bedforms on the seafloor affects sediment transport, wave attenuation, and acoustic scattering. Many studies have examined the dynamics of sediment transport and the development of bedforms on the seafloor due to the interaction of waves and currents. However, these studies have relied heavily on laboratory experiments undertaken using sands with no biological influence. This research aims to understand the effects of increased cohesion within the sediment particles resulting from biological influences (e.g., extracellular polymeric substances (EPS)) on the …


Kudzu Invasion And Control In Southern Upland Forests Of Mississippi, Gina M. Profetto Dec 2021

Kudzu Invasion And Control In Southern Upland Forests Of Mississippi, Gina M. Profetto

University of New Orleans Theses and Dissertations

Kudzu, Pueraria montana var. lobata (Willd.), is a common invasive species throughout the American South. In southern upland mixed oak-pine forests of Mississippi, kudzu invasion generally and indiscriminately suppressed the pre-invasion plant community. Three different control methods reduced kudzu density but differed in the level of reduction achieved and in their effects on the pre-existing plant community. A combination of burning and herbicides produced the most desirable outcome in terms of restoring the pre-invasion community. Kudzu invasion significantly increased nitrate pools compared to control sites, but had no effect on ammonium or nitrite, or on the microbial processes of mineralization …


Fast & Efficient Simulation For Long Polymeric Chains, Naeyma N. Islam Dec 2021

Fast & Efficient Simulation For Long Polymeric Chains, Naeyma N. Islam

University of New Orleans Theses and Dissertations

No abstract provided.


Ecological Factors Influencing Population Dynamics Of The Mississippi Sandhill Crane, Grus Canadensis Pulla, Henry W. Woolley Dec 2021

Ecological Factors Influencing Population Dynamics Of The Mississippi Sandhill Crane, Grus Canadensis Pulla, Henry W. Woolley

University of New Orleans Theses and Dissertations

My dissertation encompasses three studies involving ecological factors influencing the Mississippi sandhill crane (Grus canadensis pulla) population at Mississippi Sandhill National Wildlife Refuge. To examine influences on the historical population I studied trends in nesting, number of chicks fledged annually, and their environmental and biotic drivers during 1991-2018. I expected precipitation to be positively associated with population measures and drought, extreme heat, and predation to be inversely related to population measures. To examine the influence of current habitat food production on the crane population I quantified measures of production in 2018 and 2019 and their relationship to time …


Machine Learning For Terminal Procedure Chart Change Detection, Anthony M. Marchiafava May 2021

Machine Learning For Terminal Procedure Chart Change Detection, Anthony M. Marchiafava

University of New Orleans Theses and Dissertations

Terminal Procedure Charts are a constantly updated and necessary tool for aircraft personnel to approach and take off from airport runways safely. Detecting changes within these charts is a time-consuming and laborious process. Here machine learning techniques were used to predict regions of change in charts based on detecting the charts image regions and comparing features extracted from those regions. Outlined are methodologies to detect differences between two separate charts to produce images with changed regions clearly indicated. Both more conventional computer vision and machine learning techniques were applied. For images with minor shifts, the proposed model is able to …


The Kati Module System: Modular Design For Delivering Character Focused Dialogue In Games, Stephen J. Marcel May 2021

The Kati Module System: Modular Design For Delivering Character Focused Dialogue In Games, Stephen J. Marcel

University of New Orleans Theses and Dissertations

The Kati Module System is an interconnected set of programming modules intended to facilitate dynamic text authoring for interactive experiences (for example, games). It is a long-standing goal for interactive experiences to dynamically adapt their textual output based on the user or player's choices and predilections, but to account for this vast possibility space requires an amount of authoring that is frequently untenable, especially for small studios. Advances in machine learning have produced incredible progress in the field of Natural Language Generation (NLG). Though this produces impressive surface level text, it does so without an internal representation that can be …


Sounds Of Silence: A Study Of Stability And Diversity Of Web Audio Fingerprints, Shekhar Chalise May 2021

Sounds Of Silence: A Study Of Stability And Diversity Of Web Audio Fingerprints, Shekhar Chalise

University of New Orleans Theses and Dissertations

Browser fingerprinting presents a grave threat to privacy as it allows user tracking even in private browsing modes. Prior measurement studies on HTML5-based fingerprinting have been limited to Canvas and WebGL but not Web Audio APIs. We aim to fill this gap by conducting the first large-scale systematic study of web audio fingerprints and studying their stability as well as diversity properties. Using MTurk and social media platforms, we collected 8 different audio fingerprints from 694 users.

Firstly, we show that the audio fingerprints are unstable unlike other fingerprinting methods with some users having as many as 20 different fingerprints. …


Isolation And Determination Of The Composition And Structural Components That Comprise Dissolved Organic Matter Using Normal Phase Liquid Chromatography, Jonathan A. Long Jr May 2021

Isolation And Determination Of The Composition And Structural Components That Comprise Dissolved Organic Matter Using Normal Phase Liquid Chromatography, Jonathan A. Long Jr

University of New Orleans Theses and Dissertations

A comprehensive understanding of the reactivity associated with organic carbon is critical for recognizing the behavior of newly formed compounds in aquatic environments. In an effort to study the reactivity of complex mixtures, understanding the different processes affiliated with them are key. Understanding the reactivity associated with organic carbon can help to improve chromatographic separation. Using a combination of light and heavy crude oil, a separation procedure was developed to obtain a complete representation of the aromatic subfraction of the crude oil sample. The crude oils were separated into four distinct fractions based on the number of condensed aromatic rings …


Convolutional Neural Networks For Deflate Data Encoding Classification Of High Entropy File Fragments, Nehal Ameen May 2021

Convolutional Neural Networks For Deflate Data Encoding Classification Of High Entropy File Fragments, Nehal Ameen

University of New Orleans Theses and Dissertations

Data reconstruction is significantly improved in terms of speed and accuracy by reliable data encoding fragment classification. To date, work on this problem has been successful with file structures of low entropy that contain sparse data, such as large tables or logs. Classifying compressed, encrypted, and random data that exhibit high entropy is an inherently difficult problem that requires more advanced classification approaches. We explore the ability of convolutional neural networks and word embeddings to classify deflate data encoding of high entropy file fragments after establishing ground truth using controlled datasets. Our model is designed to either successfully classify file …


Machine Learning Based Restaurant Sales Forecasting, Austin B. Schmidt May 2021

Machine Learning Based Restaurant Sales Forecasting, Austin B. Schmidt

University of New Orleans Theses and Dissertations

To encourage proper employee scheduling for managing crew load, restaurants have a need for accurate sales forecasting. We predict partitions of sales days, so each day is broken up into three sales periods: 10:00 AM-1:59 PM, 2:00 PM-5:59 PM, and 6:00 PM-10:00 PM. This study focuses on the middle timeslot, where sales forecasts should extend for one week. We gather three years of sales between 2016-2019 from a local restaurant, to generate a new dataset for researching sales forecasting methods.

Outlined are methodologies used when going from raw data to a workable dataset. We test many machine learning models on …


Dimensionless Analysis Of Trajectories Of Cylindrical Objects Dropped Into Water In Two Dimensions, Yi Zhen May 2021

Dimensionless Analysis Of Trajectories Of Cylindrical Objects Dropped Into Water In Two Dimensions, Yi Zhen

University of New Orleans Theses and Dissertations

Nondimensionalization is powerful technique and is widely applied in the study of fluid mechanics and engineering because it helps to reduce the number of free parameters, identify the relative size of effects of parameters, and gain a deeper insight of the essential nature of phenomena. The nondimensionalization of 2D theory has been completed by the author (Zhen et.al.,2020) and new dimensionless equations of motion were obtained. In this study, new dimensionless dynamic equations are extended by incorporating new parameters to cope with various environmental conditions. The new dimensionless analysis of dropped cylindrical objects is consisted of four parts.

Part 1, …