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Articles 13501 - 13530 of 14121
Full-Text Articles in Physical Sciences and Mathematics
Optimal Adaptive Tracking Control Of Partially Uncertain Nonlinear Discrete-Time Systems Using Lifelong Hybrid Learning, Behzad Farzanegan, Rohollah Moghadam, Sarangapani Jagannathan, Pappa Natarajan
Optimal Adaptive Tracking Control Of Partially Uncertain Nonlinear Discrete-Time Systems Using Lifelong Hybrid Learning, Behzad Farzanegan, Rohollah Moghadam, Sarangapani Jagannathan, Pappa Natarajan
Electrical and Computer Engineering Faculty Research & Creative Works
This article addresses a multilayer neural network (MNN)-based optimal adaptive tracking of partially uncertain nonlinear discrete-time (DT) systems in affine form. By employing an actor–critic neural network (NN) to approximate the value function and optimal control policy, the critic NN is updated via a novel hybrid learning scheme, where its weights are adjusted once at a sampling instant and also in a finite iterative manner within the instants to enhance the convergence rate. Moreover, to deal with the persistency of excitation (PE) condition, a replay buffer is incorporated into the critic update law through concurrent learning. To address the vanishing …
Lifelong Learning-Based Multilayer Neural Network Control Of Nonlinear Continuous-Time Strict-Feedback Systems, Irfan Ahmad Ganie, S. (Sarangapani) Jagannathan
Lifelong Learning-Based Multilayer Neural Network Control Of Nonlinear Continuous-Time Strict-Feedback Systems, Irfan Ahmad Ganie, S. (Sarangapani) Jagannathan
Electrical and Computer Engineering Faculty Research & Creative Works
In This Paper, We Investigate Lifelong Learning (LL)-Based Tracking Control for Partially Uncertain Strict Feedback Nonlinear Systems with State Constraints, employing a Singular Value Decomposition (SVD) of the Multilayer Neural Networks (MNNs) Activation Function based Weight Tuning Scheme. the Novel SVD-Based Approach Extends the MNN Weight Tuning to (Formula Presented.) Layers. a Unique Online LL Method, based on Tracking Error, is Integrated into the MNN Weight Update Laws to Counteract Catastrophic Forgetting. to Adeptly Address Constraints for Safety Assurances, Taking into Account the Effects Caused by Disturbances, We Utilize a Time-Varying Barrier Lyapunov Function (TBLF) that Ensures a Uniformly Ultimately …
Introduction To Contemporary Mathematics Syllabus (Spring 2023), Heather Nunnally
Introduction To Contemporary Mathematics Syllabus (Spring 2023), Heather Nunnally
Open Textbooks and Course Materials
This syllabus was used in the Spring of 2023 for MATH 131: Introduction to Contemporary Mathematics. There were no textbook costs for this course; instead, MyOpenMath was used for the textbook and homework.
Efficient High Order Ensemble For Fluid Flow, John Carter
Efficient High Order Ensemble For Fluid Flow, John Carter
Doctoral Dissertations
"This thesis proposes efficient ensemble-based algorithms for solving the full and reduced Magnetohydrodynamics (MHD) equations. The proposed ensemble methods require solving only one linear system with multiple right-hand sides for different realizations, reducing computational cost and simulation time. Four algorithms utilize a Generalized Positive Auxiliary Variable (GPAV) approach and are demonstrated to be second-order accurate and unconditionally stable with respect to the system energy through comprehensive stability analyses and error tests. Two algorithms make use of Artificial Compressibility (AC) to update pressure and a solenoidal constraint for the magnetic field. Numerical simulations are provided to illustrate theoretical results and demonstrate …
An Unmanned Aircraft System For Marking Live Power Lines To Prevent Bird Collisions, Mattheuns D. Pretorius, Lourens Leeuwner, Kaajial Durgapersad, Constant Hoogstad, Peter Beckedahl, Michael D. Michael, Kishaylin Chetty
An Unmanned Aircraft System For Marking Live Power Lines To Prevent Bird Collisions, Mattheuns D. Pretorius, Lourens Leeuwner, Kaajial Durgapersad, Constant Hoogstad, Peter Beckedahl, Michael D. Michael, Kishaylin Chetty
Human–Wildlife Interactions
Collisions with overhead power lines represent a significant cause of mortality for a number of large bird species worldwide. Certain threatened species are severely impacted by power line collisions, particularly those for which there are no other known significant threats. In South Africa, bird collisions with overhead power line cables, including collisions with phase conductors and shield wires, contribute significantly to annual threatened bird species mortalities associated with Eskom power lines. The most practical mitigation measure is to attach bird anti-collision devices as markers on the cables. Current marking methods involve installations by hand, where linemen are hoisted up to …
Impacts Of Land Cover Change On Urban Heat Island (Uhi) In Denver From 1985 To 2020, Sadia Islam Ritu
Impacts Of Land Cover Change On Urban Heat Island (Uhi) In Denver From 1985 To 2020, Sadia Islam Ritu
Electronic Theses and Dissertations
Rapid urbanization due to land use and land cover change has become one of the major problems in the fastest-growing cities during the past few decades. Land surface temperature has changed dramatically due to urban expansion, and it is a major driver of urban eco-environmental change. Increasing temperature leads to the Urban Heat Island (UHI) problem in rapidly growing cities like Denver, contributing to global warming at multiple scales. UHI study is significant to monitor and mitigate the urban heat islandrelated problem in the study area Denver. Satellite remote sensing analysis ready data (ARD) with 30 m resolution based on …
Some 2-Color Rado Numbers For A Linear Equation With A Negative Constant, Rachel Bergjord
Some 2-Color Rado Numbers For A Linear Equation With A Negative Constant, Rachel Bergjord
Electronic Theses and Dissertations
An r-coloring is a function Δ that assigns a color to each natural number from 1 to some number n using colors 0, 1, . . . , r − 1. A monochromatic solution (in Δ) to an equation L with m variables is an ordered m-tuple (x1, x2, . . . , xm) where Δ(x1) = Δ(x2) = · · · = Δ(xm) and (x1, x2, . . . , xm−1, xm) solves L. Given a linear equation L and t ∈ N, the t-color Rado number for L is the least integer n (if it exists) such that …
Identification And Quantification Of Novel Antimicrobials, Hazera Khatun Koly
Identification And Quantification Of Novel Antimicrobials, Hazera Khatun Koly
Electronic Theses and Dissertations
No abstract provided.
Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer
Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer
Electronic Theses and Dissertations
Corn (Zea mays L.) is a vital commodity in South Dakota’s agricultural sector. Optimal corn production occurs when there are sufficient mineral nutrients in the soil, especially potassium (K). Applications of K fertilizer are used when soil test K (STK) levels are deficient. Therefore, producers need reliable, thoroughly tested fertilizer recommendations to make profitable decisions and maintain environmental stewardship. South Dakota K fertilizer recommendations have not been updated in nearly 20 years. Simultaneously, changes in corn genetics, management practices, and climate patterns suggest that the critical soil test value (CSTV) for STK may have shifted in that same time frame. …
Cytotoxicity Profiling And Apoptotic Potential Of Carboxylic Acids-Based Deep Eutectic Solvents On Mammalian Cell Lines, Mavis Korankye
Cytotoxicity Profiling And Apoptotic Potential Of Carboxylic Acids-Based Deep Eutectic Solvents On Mammalian Cell Lines, Mavis Korankye
Electronic Theses and Dissertations
In the past few years, there has been a notable surge in demand for high-purity medicines due to the prevalence of chronic diseases such as cancer, hypertension, diabetes, cardiovascular diseases, and neurological disorders. Considerable efforts have been dedicated to discovering new solvents that are environmentally friendly and cost-effective that are well-suited for industrial applications. Deep eutectic solvents have gained recognition as a highly promising alternative to organic solvents and ionic liquids due to their easily sourced raw materials, simple and cheap preparation methods, high tunability, low volatility, low toxicity, and biodegradability. The industrial utilization of deep eutectic solvents (DESs) is …
The Live Bait Trade As A Pathway Of Inland Invasive Fish Species Introductions, Hannah Mulligan
The Live Bait Trade As A Pathway Of Inland Invasive Fish Species Introductions, Hannah Mulligan
Electronic Theses and Dissertations
Freshwater systems are susceptible to numerous anthropogenic pathways of invasive species introductions and subsequent establishment. Once establishment occurs, invasive species not only impact biodiversity, ecosystem function, and human health, but also cost the global economy billions of dollars every year. Recreational fishing is one of the most prevalent pathways for invasive species introductions in freshwater systems due to increased propagule pressure from boating and angling activity. Within recreational fishing, the live bait trade represents a secondary pathway whereby anglers illegally release baitfish (and water) that may contain invasive species. Preventative actions, including regulations, education, and inspections have been implemented to …
Understanding The Role Of Hba/Hbd Variations On Deep Eutectic Solvent Properties And Activity Using Acetylsalicylic Acid As A Model Drug, Michael Frimpong
Understanding The Role Of Hba/Hbd Variations On Deep Eutectic Solvent Properties And Activity Using Acetylsalicylic Acid As A Model Drug, Michael Frimpong
Electronic Theses and Dissertations
Deep eutectic solvents (DES) are emerging as a versatile class of solvents, attracting considerable attention for their unique solvent properties and potential applications. This study examines the effects of variations in combinations as well as molar ratios of hydrogen-bond acceptor (HBA) and hydrogen-bond donor (HBD) on the structure of DES. It further explores the structure-activity relationship, measured using the rate of acetylsalicylic acid (ASA) degradation in the solvent. The project is based on the model that variations in HBA/HBD combinations and their relative molar ratios impact the solvent structure (hydrogen bonding), observable in physicochemical measurements, infrared (IR), and nuclear magnetic …
Effects Of Agricultural Chemicals On Native Plants Of The Northern Great Plains, Gabrielle Bolwerk
Effects Of Agricultural Chemicals On Native Plants Of The Northern Great Plains, Gabrielle Bolwerk
Electronic Theses and Dissertations
Agricultural chemicals are ubiquitous on the Northern Great Plains landscape and have negative impacts on non-target plant communities, even at small doses. Northern Great Plains grassland plant communities may experience herbicide drift from agricultural fields or be subject to livestock pharmaceuticals in grazing lands. My research objective was to evaluate if and how native plants are affected by agricultural chemical presence at different concentrations. In Chapter 2, I studied the effect of different concentrations of three common agricultural herbicides (2,4-D, atrazine, and trifluralin) on the germination, emergence, and growth of native plant species of the Northern Great Plains. I performed …
Investigations Into The Electronic And Magnetic Properties Of (Crps4)N Layers, Alexandria R. Alcantara
Investigations Into The Electronic And Magnetic Properties Of (Crps4)N Layers, Alexandria R. Alcantara
UNF Graduate Theses and Dissertations
2D magnetic semiconductors have become of interest due to their magneto-optical effects in lower dimensionality. More specifically, CrPS4 has gained renewed attention due to its A-type AFM order and air stability prompting analysis and stability studies in its layered forms for use in scalable technology such as spintronic and optoelectronic devices. In this study, we benchmark our approach using the SCAN meta-GGA functional used without U-parameterization on bulk CrPS4 to demonstrate the accuracy of our methodology to use as tools to go beyond current CrPS4 theoretical studies. We examine the 2D electronic nature and optical spectrum for use in experimental …
Elliptic Functions And Iterative Algorithms For Π, Eduardo Jose Evans
Elliptic Functions And Iterative Algorithms For Π, Eduardo Jose Evans
UNF Graduate Theses and Dissertations
Preliminary identities in the theory of basic hypergeometric series, or `q-series', are proven. These include q-analogues of the exponential function, which lead to a fairly simple proof of Jacobi's celebrated triple product identity due to Andrews. The Dedekind eta function is introduced and a few identities of it derived. Euler's pentagonal number theorem is shown as a special case of Ramanujan's theta function and Watson's quintuple product identity is proved in a manner given by Carlitz and Subbarao. The Jacobian theta functions are introduced as special kinds of basic hypergeometric series and various relations between them derived using the triple …
The Lie Algebra Sl2(C) And Krawtchouk Polynomials, Nkosi Alexander
The Lie Algebra Sl2(C) And Krawtchouk Polynomials, Nkosi Alexander
UNF Graduate Theses and Dissertations
The Lie algebra L = sl2(C) consists of the 2 × 2 complex matrices that have trace zero, together with the Lie bracket [y, z] = yz − zy. In this thesis we study a relationship between L and Krawtchouk polynomials. We consider a type of element in L said to be normalized semisimple. Let a, a^∗ be normalized semisimple elements that generate L. We show that a, a^∗ satisfy a pair of relations, called the Askey-Wilson relations. For a positive integer N, we consider an (N + 1)-dimensional irreducible L-module V consisting of the homogeneous polynomials in two variables …
Breast Density Classification Using Deep Learning, Conrad Thomas Testagrose
Breast Density Classification Using Deep Learning, Conrad Thomas Testagrose
UNF Graduate Theses and Dissertations
Breast density screenings are an accepted means to determine a patient's predisposed risk of breast cancer development. Although the direct correlation is not fully understood, breast cancer risk increases with higher levels of mammographic breast density. Radiologists visually assess a patient's breast density using mammogram images and assign a density score based on four breast density categories outlined by the Breast Imaging and Reporting Data Systems (BI-RADS). There have been efforts to develop automated tools that assist radiologists with increasing workloads and to help reduce the intra- and inter-rater variability between radiologists. In this thesis, I explored two deep-learning-based approaches …
Assessing The Performance Of A Particle Swarm Optimization Mobility Algorithm In A Hybrid Wi-Fi/Lora Flying Ad Hoc Network, William David Paredes
Assessing The Performance Of A Particle Swarm Optimization Mobility Algorithm In A Hybrid Wi-Fi/Lora Flying Ad Hoc Network, William David Paredes
UNF Graduate Theses and Dissertations
Research on Flying Ad-Hoc Networks (FANETs) has increased due to the availability of Unmanned Aerial Vehicles (UAVs) and the electronic components that control and connect them. Many applications, such as 3D mapping, construction inspection, or emergency response operations could benefit from an application and adaptation of swarm intelligence-based deployments of multiple UAVs. Such groups of cooperating UAVs, through the use of local rules, could be seen as network nodes establishing an ad-hoc network for communication purposes.
One FANET application is to provide communication coverage over an area where communication infrastructure is unavailable. A crucial part of a FANET implementation is …
Apparent Contours For Piecewise Smooth Surfaces, Sarah Marie Jackman
Apparent Contours For Piecewise Smooth Surfaces, Sarah Marie Jackman
UNF Graduate Theses and Dissertations
The set of points on an embedded surface $M$ that are tangent to a set viewing direction $\mathbf{v}$ is called the contour generator of $M$. The projection of those points to an image plane is called a surface's apparent contour. Apparent contours hold certain properties that allow for reconstruction of the original surface using only the information of the apparent contour. In this paper, we explore the structure of the apparent contour through contact classes and singularity types. Additionally we examine the properties of apparent contours that allow for 3 dimensional reconstruction. Our goal is to extend the properties of …
Exploring Mottness And Electronic Order In Strongly Correlated Vanadate Thin Films, Nathan Bairen
Exploring Mottness And Electronic Order In Strongly Correlated Vanadate Thin Films, Nathan Bairen
UNF Graduate Theses and Dissertations
Mott insulators provide a window into some of the most intensely investigated phenomena in physics. Recent discoveries—including the emergence of high-temperature superconductivity in doped Mott insulators not from the cuprate family of superconductors—have inspired investigation into systems with strong electron-electron interactions. One of these systems is La1-xSrxVO3, in which one end-member, LaVO3, is a Mott insulator and the other, SrVO3, is a strongly correlated metal.
Herein, we detail two studies regarding this system. In our oxidation study, we optimized the growth parameters for LaVO3, finding that the ultra-high vacuum technique …
Ovulation Prediction Using Random Forest Algorithm On Physiological Data, Kimberly D. Laynes
Ovulation Prediction Using Random Forest Algorithm On Physiological Data, Kimberly D. Laynes
UNF Graduate Theses and Dissertations
Human infertility rates are on the rise -- studies have shown that one in every four women have trouble conceiving and every year those rates are rising [Halleran22]. This trend motivates procedures such as in-vitro fertilization (IVF) and intrauterine insemination (IUI) to produce a pregnancy. Such procedures are not only intricate and expensive but also carry potential unintended consequences for women's physical and mental well-being. A more profound comprehension of the menstrual cycle and its multiple phases, particularly detecting the ovulation period itself, promotes optimized treatment outcomes and reduces associated risks. To facilitate ovulation detection, new sensing technologies built into …
Extracting Road Surface Marking Features From Aerial Images Using Deep Learning, Michael Kimollo
Extracting Road Surface Marking Features From Aerial Images Using Deep Learning, Michael Kimollo
UNF Graduate Theses and Dissertations
The traffic and roadway safety agencies spend significant efforts each year collecting roadway data, including lane configurations and other road surface marking data, such as areas with school zone markings, sidewalks, left turns, right turns, bicycle lanes, etc., for safety analysis and planning purposes. The current manual data collection methods pose significant operational and quality control challenges as they are costly and prone to errors. In addition to that the manual data collection is labor intensive and takes too much time involving high equipment costs, questionable data accuracy guarantees, and concerns about the safety of the crew.
This study aims …
Novel Approaches To Compute Manifold Operators With The Radial Basis Functions Method, Jacob James Blazejewski
Novel Approaches To Compute Manifold Operators With The Radial Basis Functions Method, Jacob James Blazejewski
Dissertations, Master's Theses and Master's Reports
The bulk of this dissertation is mainly composed of four chapters, which are organized as follows: Chapter 1 provides an introduction to the Radial Basis Functions (RBF) method by briefly outlining its historical developments and reviewing the RBF interpolation and the RBF-Finite Difference (FD) methodologies, and their advantages/disadvantages. Chapter 2 describes the Orthogonal Gradients (OGr) method and the Fast OGr method and how these can be used to compute differential operators restricted to hypersurfaces and space curves ($\Gamma$) embedded in R3. We will highlight a challenge of pairing Fast OGr with RBF-FD on nearly flat local clusters and how to …
Additive P-Value Combination Test, Xing Ling
Additive P-Value Combination Test, Xing Ling
Dissertations, Master's Theses and Master's Reports
This dissertation includes four Chapters. A brief description of each chapter is organized as follows.
In Chapter 1, some developments on multiple hypotheses tests are introduced. Some preliminaries about the definition and the assumption are included.
In Chapter 2, a Stable Combination Test is proposed to combine $p$-values from multiple hypotheses tests. We show the proposed method controls the family-wise error rate at the target level and maintains asymptotically optimal power even when the elementary p-values from the individual hypotheses are dependent.
In Chapter 3, a deeper dig into the additive p-value combination test is performed. A common idea behind …
Invasive Buckthorn Mapping: A Uav-Based Approach Utilizing Machine Learning, Gis, And Remote Sensing Techniques In The Upper Peninsula Of Michigan, Vikranth Madeppa
Invasive Buckthorn Mapping: A Uav-Based Approach Utilizing Machine Learning, Gis, And Remote Sensing Techniques In The Upper Peninsula Of Michigan, Vikranth Madeppa
Dissertations, Master's Theses and Master's Reports
An Invasive species is a species that is alien or non-native to the ecosystem which causes harm to economic, environmental, or human health (E.O. 13112 of Feb 3, 1999). Invasive species have posed a serious threat to ecosystems across the globe. These invasive species have impacts on the biodiversity and productivity of invaded forests. Remotely sensed data is a valuable resource for understanding and addressing issues related to invasive species. This study presents a novel approach for mapping the distribution of two invasive plant species, Common and Glossy Buckthorn, using unmanned aerial vehicles (UAVs), machine learning algorithms, geographic information systems …
Climate Changes In El Salvador: Impacts Of ‘La Canícula’ (Midsummer Drought) On Agricultural Practices And Decision-Making In Rural Communities, Paola M. Rivera González
Climate Changes In El Salvador: Impacts Of ‘La Canícula’ (Midsummer Drought) On Agricultural Practices And Decision-Making In Rural Communities, Paola M. Rivera González
Dissertations, Master's Theses and Master's Reports
The Central American Dry Corridor (CADC), a tropical, dry-forest region, is characterized by distinct rainy and dry seasons, which influence the local agricultural calendar and planting decisions in rural communities. La canícula is a period of decreased precipitation during the rainy season, which occurs during the corn-planting season in El Salvador. La canícula is expected to change in intensity and duration in the next decades, which would impact small-scale farmers and their livelihoods. Climate variability and uncertainty has led to crop loss, water scarcity, and food insecurity in rural communities dependent on subsistence farming. Farmers’ experiences with a changing climate …
Chemical Decomposition Of Flexible Polyurethane Foam To Generate A Media For Microbial Upcycling, Kaushik Baruah
Chemical Decomposition Of Flexible Polyurethane Foam To Generate A Media For Microbial Upcycling, Kaushik Baruah
Dissertations, Master's Theses and Master's Reports
Polyurethane waste is becoming a global concern as a large amount is being disposed of in landfills every year, and only a fraction is being recycled. Several polyurethane recycling techniques exist, of which ammonolysis and base-catalyzed hydrolysis is the least explored. Flexible polyurethane foam (FPUF) decomposition can generate amines that can act as a carbon source for the growth of microbial consortia. This study aims to generate a novel media capable of microbial upcycling via ammonolysis and base-catalyzed hydrolysis of flexible polyurethane foams (FPUFs) using ammonium hydroxide and subsequently determine the reaction conditions for maximum solubilization of polyurethane foam in …
Structural Analysis And Slip Kinematics Of The Keweenaw Fault System Between Bête Grise Bay And Gratiot Lake, Keweenaw County, Michigan, Daniel J. Lizzadro-Mcpherson
Structural Analysis And Slip Kinematics Of The Keweenaw Fault System Between Bête Grise Bay And Gratiot Lake, Keweenaw County, Michigan, Daniel J. Lizzadro-Mcpherson
Dissertations, Master's Theses and Master's Reports
The Keweenaw fault is perhaps the most significant geologic structure on the Keweenaw Peninsula, with an estimated 7-11 km of reverse slip juxtaposing volcanic strata of the ~1.1 Ga Portage Lake Volcanics above ~1.0 Ga Jacobsville Sandstone. The fault has been interpreted as a rift-bounding normal fault later inverted by compressional pulses of the Grenville Orogeny or, more recently, as part of a detached thrust fault system unrelated to an earlier normal fault. The fault is shown on published maps as a single continuous fault trace whose sinuosity implies multiple fault segments and complex slip dynamics. Mapping along Bête Grise …
Study Of Electronic And Magnetic Properties Of Bilayer Graphene Nanoflakes And Bimetallic Chalcogenides Using First-Principles Density Functional Theory And Machine Learning, Dharmendra Pant
Dissertations, Master's Theses and Master's Reports
Graphene, a one-atom-thick material, has been a wonder material since its discovery because of its superlative electronic, mechanical, and optical properties. When a layer of graphene is rotated over another layer, it exhibits many intriguing behaviors, ranging from superconductivity to the anomalous Hall effect to ferromagnetism at a magic angle of 1°, and hence the twisted bilayer graphene has been the subject of intense research in recent years. The surge in interest in this moiré structure can be attributed to the emergence of electronic flat minibands near the magic angle. Here, we studied the electronic and magnetic properties of twisted …
Multiscale Molecular Modeling Studies Of The Dynamics And Catalytic Mechanisms Of Iron(Ii)- And Zinc(Ii)-Dependent Metalloenzymes, Sodiq O. Waheed
Multiscale Molecular Modeling Studies Of The Dynamics And Catalytic Mechanisms Of Iron(Ii)- And Zinc(Ii)-Dependent Metalloenzymes, Sodiq O. Waheed
Dissertations, Master's Theses and Master's Reports
Enzymes are biological systems that aid in specific biochemical reactions. They lower the reaction barrier, thus speeding up the reaction rate. A detailed knowledge of enzymes will not be achievable without computational modeling as it offers insight into atomistic details and catalytic species, which are crucial to designing enzyme-specific inhibitors and impossible to gain experimentally. This dissertation employs advanced multiscale computational approaches to study the dynamics and reaction mechanisms of non-heme Fe(II) and 2-oxoglutarate (2OG) dependent oxygenases, including AlkB, AlkBH2, TET2, and KDM4E, involved in DNA and histone demethylation. It also focuses on Zn(II) dependent matrix metalloproteinase-1 (MMP-1), which helps …