Digital Commons Network^™

Remote Sensing Assessment Of Ionospheric Total Electron Content Over Thanjavur Gps Station Geomagnetic 2.91 N 152.22 E, Veera Kumar Maheswaran

Theses and Dissertations

A Global Positioning System (GPS) station for ionosphere studies was established during December 2019 in Thanjavur (Geographic 10.72◦ E, 79.01◦ N, Geomagnetic 2.91◦ N, 152.22◦ E). The study involved analysing Total Electron Content (TEC) data and correcting biases to estimate Slant Total Electron Content (STEC). STEC was then converted to Vertical Total Electron Content (VTEC), useful for space weather, navigation, surveying, and environmental monitoring.

During the course of our study, this Thanjavur station witnessed a Annular Solar eclipse of Dec-26, 2019. The Solar eclipses can impact ionospheric conditions, causing VTEC depletion. This study shows how the near-earth environment changes during …

Motion Based Analysis Of Ultrasound Imaging For The Study Of Musculoskeletal Tissue Bio Mechanics, Ananth Hari R

Theses and Dissertations

Ultrasound image analysis plays an important role in diagnosing musculoskeletal injuries and monitoring rehabilitation exercises. The first and foremost step in this analysis involves segmentation of region of interest from the ultrasound images. The segmentation of the musculoskeletal tissues from the ultrasound images is challenging due to the inherent drawback present in ultrasound like : (1) Poor image quality due to image corruption by speckle noise, shadows, and attenuation. (2) Dis-continuous boundaries due to orientation dependence during the acquisition of image. (3) Low contrast between nearby anatomical structures. Hence in order to overcome these drawbacks, there is a need for …

Improving Fatigue Characteristics Of Cold Formed Low Carbon Steel, Venkatesan D

Theses and Dissertations

EN353 is a low carbon alloy steel, predominantly used in the manufacturing of heavy-duty gears, shafts, and pinions, especially crown wheel and pinions. It is usually carburized, hardened, and tempered to produce a hard, wear-resistant case. Heat- treated EN353 steel exhibits enhancement in ductility, toughness, strength, and hardness as the internal stresses get relieved in the material. Spheroidizing of medium and high carbon steel is a method of prolonged heating at a temperature below the eutectoid temperature, where pearlite, the lowest energy arrangement of steel, gets converted to ferrite and cementite.

The graphite content of steel assumes a spheroidal shape, …

Identification Of Delamination Defect In Fibre Reinforced Polymer Composite Tapered Plate Based On Vibration Measurement, Venkatesan M

Theses and Dissertations

Fibre-reinforced polymer (FRP) composite plates have been widely used in various engineering applications due to their high strength-to-weight ratio, corrosion resistance, and durability. Despite their many benefits, Delamination is a separation of the layers in composite material and can occur due to various factors such as impact, fatigue, and manufacturing defects. Identifying delamination in composite structures is crucial for ensuring safety and reliability. In this study, model-dependent vibration methods, which are an effective non-destructive technique, were utilised for delamination identification. The primary objective is to investigate the dynamic behaviour of delaminated thickness-tapered plates and develop a reliable methodology for delamination …

Abnormal Event Detection Using Hypergraph Based Multiple Objects Tracking Techniques In Surveillance Videos, Palanivel S

Theses and Dissertations

Abnormal event detection aims to identify the events that deviate from expected normal patterns. This work primarily focuses on detection of rare events in public places. The existing research challenges in a video-based surveillance systems for the vehicle have been analysed and presence of abnormal objects in traffic-oriented videos have been detected. A novel approach for event summarization and rare event detection has been proposed in this work. The key ingredient in this work is the incorporation of Hypergraph (HG) matching.

Despite the reasonable amount of success achieved by a large number of researchers over the globe, distinguishing important videos …

Mathematics In Sri Rudram Of Krishna Yajurveda Taittiriya Samhita, Sundar Ks

Theses and Dissertations

This thesis is an attempt to bring out the concealed mathematical information in the Vedic text “Śri Rudram”, by applying Vedic Numerical Code to digitally decode the mantras in the Śri Rudram which forms part of the fourth canto of the Krishna Yajur Veda Taittiriya Samhitā.

By converting the letters into numbers, it was possible to handle the concealed information in a mathematical and logical way to successfully arrive at a convincing reason for the traditional practice of chanting Śri Rudram eleven times in a particular prescribed manner; as well as finding the close relationship between the number 11 and …

Mg3sb2-Based Materials For Mid-Temperature Thermoelectric Application, Veera Prabhu K

Theses and Dissertations

Recently, there has been growing research in the scientific community regarding the conversion of heat flux into electricity, which has proven effective in mitigating energy crises. Solid-state thermoelectric (TE) devices use the Seebeck effect to efficiently convert waste heat into electricity. Traditional materials contain toxic, rare, and expensive elements like Lead, Tellurium, and Germanium that restrict large-scale production, commercialization, and practical utilization.

Recently, Mg3Sb2-based materials have been attractive due to their remarkable characteristics, including abundance, affordability, and environmental friendliness. Furthermore,n-type Mg3Sb2-based materials exhibit high TE performance because of their high band degeneracy in the conduction band minimum (CBM), and low …

Emergence Of Extreme Events In Nonlinear Oscillators Due To Parametric And External Excitations, Kaviya B

Theses and Dissertations

This comprehensive PhD thesis immerses itself in the intricate world of dynamical systems, aiming to understand, characterize, and develop innovative mitigation strategies for rare and extreme events occurring within diverse nonlinear oscillatory models. The term "events" spans a broad array of occurrences within defined systems, with "rare events" standing out as infrequent outliers or deviations from the norm.

Rare events span various disciplines such as oceanography, climate studies, biology, economics, ecology, encompassing phenomena like rogue waves, floods, cyclones, earthquakes, and financial crises. Recognized for their potential to cause substantial harm to both society and the environment, these events are widely …

An Adaptive Hybrid Deep Learning Architecture For Providing Guaranteed Qos In 5g Cellular Networks, Rajilal Mv Ms

Theses and Dissertations

Wireless network systems must have effective resource allocation, particularly in the context of 5G networks when flexibility is needed to meet a range of network requirements. Resource allocation is essential in cellular network contexts to guarantee equitable access to customers, partners, and cellular service users. Since resource distribution determines network performance, it offers significant advantages when executed well. One of the biggest issues with 5G technology is resource allocation, particularly when it comes to the Quality of Service (QoS) for various applications. Resources in wireless networks include items like channels, power, and spectrum; these must all be apportioned according to …

Analysis Of Isotopic Effects On Hydrogen Oxidation, Jacob Carter Wilde

Theses and Dissertations

Tritium generation presents a significant hazard during operation of nuclear reactors and necessitates safety precautions in the case of a combustion incident. Accurate kinetic models should inform these safety precautions, however, reliable tritium data do not exist to generate such models. This work focuses on laminar flame speed, which is an important component of kinetic models. Current estimates based on established kinetic theories and experimental measurements of the other isotopes of hydrogen predict tritium to have a flame speed approximately 70% that of standard protium over a broad range of stoichiometries at one atmosphere in air. These estimates are based …

Geology Of Sinai Tholus, Thaumasia Plateau, Mars, Haley Mosher

Theses and Dissertations

A new geologic map of the Sinai Tholus region on the Thaumasia plateau, Mars reveals the structural, magmatic, and stratigraphic complexity that can be found in the Tharsis region on Mars, and may help answer key questions about the origin of the subvolcanic basement, evolution of the regional stress field, development of Valles Marineris, and magmatic history of the region. Sinai Tholus is a topographic high in a relatively flat, lava flow covered part of Thaumasia Plateau, just south of the central part of Valles Marineris. Here, five stratigraphic units and one generalized impact unit have been mapped at a …

Phosphorene As A Chemical Nanosensor For Volatile Organic Compound Vapours - A Dft Outlook, Saravanan S

Theses and Dissertations

Based on the density functional theory framework, the structural stability of phosphorene allotropes and its various nanostructures are ensured. The various allotropes of phosphorene and its nanostructures such as nanosheets, nanoribbon and nanotubes are used as adsorbing materials for various volatile organic compounds (VOCs) such as alcohols, chloroform, amines and aldehydes. The results of adsorption energy are used to confirm physisorption or chemisorption of VOCs on phosphorene. In addition, the charge transfer outcome suggests whether phosphorene is acting as acceptor or donor of electrons upon interaction of target VOCs.

The electronic attributes such as band structure, projected density of states …

Enhancing The Efficacy Of Task-Based Grammar Teaching: A Study Through Error Analysis Of Esl Learners At The Tertiary Level, Dhivya P

Theses and Dissertations

This study aims to determine the effectiveness of modern methods of teaching grammar and to test the student's learning through activities and games. The objective is to identify the students' grammatical errors regarding prepositions, articles, concord, tenses, and redundancy by practical methods and task-based activities. The study employed Corder’s Error Analysis method to understand the students' language learning process, indicate errors, and identify opportunities to develop learners' language awareness.

A pilot study was conducted involving both pre test and posttest for the students. The primary research involved pre test, posttest and retention tests for the students to evaluate the error …

Hot Wire Chemical Vapor Deposition Of Tungsten Oxides For Photocatalytic Hydrogen Production From Water, Marvin Bonney

Theses and Dissertations

Anthropogenic climate change has generated an ever-increasing global ecological, economic, and political disaster for the world. In order to contain the damage and bring atmospheric carbon under control, human use of non-renewable hydrocarbons as the primary source of fuels for transportation and electrical generation needs to be phased out at the earliest possible date. Renewable, clean energy generation is currently technologically feasible and could provide the means for decarbonization of the global energy economy, but has to overcome challenges related to the intermittency of production. Hydrogen gas is a clean burning, renewable, and highly flexible method of storing such energy …

Informatics-Based Discovery Of New Natural Products, Their Biosynthesis, And Their Biological Roles, Ethan Older

Theses and Dissertations

In this work, genome mining and biosynthetic knowledge are applied for the discovery of new natural products, their biosynthetic pathways, and their promising biological activities and roles through the development of two unique new informatics-based approaches.

In chapter one, an overview of microbial natural product biological functions and biosynthesis is provided. The use of bioinformatics leveraging microbial natural product biosynthetic knowledge is also introduced. This chapter highlights the importance and need for developing innovative approaches to accessing microbial natural products, a vastly untapped source of new molecules with promising biological activities.

In chapter two, a correlational network linking the gene-encoded …

Approximate Computing And In-Memory Computing: The Best Of The Two Worlds!, Mohammed Essa Fawzy Essa

Theses and Dissertations

Machine learning (ML) has become ubiquitous, integrating into numerous real-life applications. However, meeting the computational demands of ML systems is challenging, as existing computing platforms are constrained by memory bandwidth, and technology scaling no longer yields substantial improvements in system performance. This work introduces novel hardware architectures to accelerate ML workloads, addressing both compute and memory challenges. In the compute domain, we explore various approximate computing techniques to assess their efficacy in accelerating ML computations. Subsequently, we propose the Approximate Tensor Processing Unit (APTPU), a hardware accelerator that utilizes approximate processing elements to replace direct quantization of inputs and weights …

Mild Hydrothermal Crystal Growth Strategies For Complex Inorganic Metal Fluorides, Navindra Keerthisinghe

Theses and Dissertations

Inorganic metal fluorides have been investigated for their interesting magnetic and optical properties, their electrochemical behavior, and their ionic conductivity. Fluoride materials can accommodate metals in very low oxidation states, which can be advantageous for designing new magnetic materials. Specifically, mixed metal fluorides incorporating transition metal cations often exhibit interesting magnetic behavior, such as frustrated magnetism. However, many challenges are encountered during the synthesis of such fluoride materials, including the inability to perform reactions under ambient conditions and the involvement of toxic gases for fluorination during solid-state reactions. Therefore, solution growth techniques such as mild hydrothermal synthesis are currently utilized …

Diversification And Evolution Of Hawaiian Megalagrion Damselflies (Pinapinao, Odonata: Coenagrionidae), Robert K. Hadfield

Theses and Dissertations

The Megalagrion damselflies of HawaiÊ»i present a valuable study system for understanding the impacts of geology on evolutionary processes. Despite their significance, our understanding of the temporal, geographic, and phylogenetic origins of these damselflies remains incomplete. Prior phylogenetic studies have proposed adaptive ecological and morphological progressions, but evaluating these hypotheses relies on a sound understanding of phylogenetic relationships within the genus. Previous phylogenetic analyses have produced conflicting topologies. To resolve these uncertainties, we performed phylogenetic analyses including divergence time estimation with 90 nuclear loci (>50 kbp) and 2 mitochondrial loci (>1000 bp), sampling representatives from each genus within …

Examining The Overall Impact Of Computer-Based Mathematics Instruction On Math Achievement In An Alternative High School, Jacqueline Levon Gilyard

Theses and Dissertations

Over the past decade, the United States has witnessed a remarkable surge in computer-based instruction, revolutionizing the way students learn and educators teach. This action research study aimed to investigate the overall impact of computer-based instruction on mathematics achievement in the alternative high school setting. The research design incorporated both quantitative and qualitative methods to gather comprehensive data for twenty high school students enrolled in an alternative high school setting. The quantitative data analysis involved examining pre-and post-test scores, graduation data, and final course grades to assess the effect of computer-based instruction on mathematics achievement. All of the students showed …

Examining The Impact Of A Professional Learning Community On Teachers' Awareness Of Neurodiversity In The Classroom, Taylor Diane Williams

Theses and Dissertations

In this action research study, the researcher sought to explore the influence of Professional Learning Community (PLC) participation on the recognition and awareness of general education teachers on neurodiversity in their classrooms. Additionally, the study aimed to investigate the effects of the teachers’ awareness on their instructional approaches. The participants of this study hail from a variety of cultures and languages from around the world. Conducted over a six-week period in an international school in southern Germany, the participants demonstrated an enhanced understandings of neurodiversity through their engagement in the PLC sessions. The data collection tools used in the study …

Evaluating Nutrient Limitation Of Phytoplankton Growth In North Inlet Estuary, Sc, Catherine Schlenker

Theses and Dissertations

The biolimiting nutrients nitrogen (N) and phosphorus (P) are vital components of molecules essential to life. In marine systems, N:P ratios tend to follow the “Redfield ratio” of 16:1, which is often used to infer nutrient limitation of phytoplankton biomass. Traditionally, estuaries are thought to be N-limited (N:P < 16), but there have been increasing instances of P-limitation (N:P > 16) in coastal waters worldwide. Over the last few decades, nutrient loading in North Inlet Estuary (NIE) has changed such that dissolved inorganic nitrogen (DIN):dissolved inorganic phosphorus (DIP) ratios have increased by ca. 130%. This increase suggests that the estuary may be transitioning to N and P colimitation or primary P-limitation. We …

Modeling, Analysis, Approximation, And Application Of Viscoelastic Structures And Anomalous Transport, Yiqun Li

Theses and Dissertations

(Variable-order) fractional partial differential equations are emerging as a competitive means to integer-order PDEs in characterizing the memory and hereditary properties of physical processes, e.g., anomalously diffusive transport, viscoelastic mechanics and financial mathematics, and thus have attracted widespread attention. In particular, optimal control problems governed by fractional partial differential equations are attracting increasing attentions since they are shown to provide competitive descriptions of challenging physical phenomena. Nevertheless, variable-order fractional models exhibit salient features compared with their constant-order analogues and introduce mathematical difficulties that are not typical encountered in the context of integer-order and constant-order fractional partial differential equations.

This dissertation …

Controlling Properties Of Hybrid Materials: Leaching Kinetics And Electronic Structure, Anna Berseneva

Theses and Dissertations

Hybrid materials are a unique class of materials that merge the properties of organic and inorganic building blocks. These materials are at the frontier of material science due to their wide modularity and applicability in numerous fields, ranging from catalysis to nuclear waste treatment. Unprecedented tunability of physical properties via changes in organic, inorganic moieties and their connectivity, enables for hybrid materials to address current challenges in the materials’ applications improving energy landscape.

The presented work consists of six chapters where the synthesis and design of new hybrid materials, fundamental understanding of electronic behavior and its modulation in organic-inorganic materials, …

Classifying Floor Accelerations For Gait Estimation And Detection, Jean Michel Franco Lozada

Theses and Dissertations

Structural vibrations are traditionally used to learn about structural systems, such as determining the dynamic characteristics of a structure and evaluating its structural performance under certain dynamic loads. Recently, researchers have proposed the use of structural vibrations to know more about the occupants of the structure in addition to the structure itself. One example of such would be to determine when a person falls, or to identify the location of a person walking in a building. Using structural vibrations to study occupants can be directly applicable to many fields, ranging from healthcare to security applications. One powerful use of structural …

Tax Client Goals, Regulatory Pressure, And Professional Decision-Making, Spenser G. Seifert

Theses and Dissertations

Drawing on goal theory, I illuminate how client preferences become internalized goals for tax professionals and how these client goals influence the motivated reasoning and ultimate decision-making of tax professionals. Using this theoretical framework, I then utilize an experiment to explore how the presence of salient situational factors – goal specificity, goal progress, and regulatory pressure – influence tax professionals’ decision-making. The results suggest that, as a result of their roles as both client advocates and CPAs, tax professionals default to non-specific “do your best” goals regardless of client preference specificity. Additionally, I find that increased regulatory pressure may curb …

Thermodynamic Modeling Of Uranium Nitride With Select Actinides And Fission Products, Eric Reece Mcmanus

Theses and Dissertations

Uranium mononitride fuel is being investigated as a potential nuclear fuel for a Westinghouse lead-cooled fast reactor due to factors such as its high uranium density, high melting point, and favorable thermal conductivity. To obtain an understanding of the thermochemical behavior of UN fission products and minor actinides, thermodynamic data was obtained from various resources to create a database to represent the behavior of the fuel. This database was used to generate an Ellingham diagram to represent the relative thermodynamic stability of the phases over the reactor temperature range. A simulation was run computing the equilibrium state of the fuel, …

Bass-Triadic Cadence Formulae In Melchior Neusidler’S Original Compositions From Il Primo (-Secondo) Intabolatura Di Liuto, Christopher Mcdonald

Theses and Dissertations

There was a paradigmatic shift in the discourse surrounding lute music between the early sixteenth and seventeenth centuries. The lute treatises written by early sixteenth-century German lutenists, such as Hans Judenkünig, Hanse Gerle, and Hans Newsidler, focused on technical directives that support a linear conception of music. However, lutenists active in the late sixteenth and early seventeenth century, such as Matthaeus Waissel and Jean-Baptiste Besard, describe technical accommodations for vertically conceived structures. Contemporaneously, at the turn of the seventeenth century, the discourse on bass primacy and triadic structures developed from an undercurrent, cast in the shadow of counterpoint treatises, to …

Evaluation Of A Statewide Suicide Awareness And Prevention Program, Darien Collins

Theses and Dissertations

Mental health challenges are prevalent among young people in South Carolina, with suicide being a leading cause of death for individuals aged 10 to 24. Ending the Silence (ETS) serves as a gatekeeper training to engage students, school staff, families, and community members in conversations surrounding mental health challenges and suicide awareness. The University of South Carolina School Behavioral Health Team (SBHT), led by Dr. Mark Weist, with funding from the South Carolina (SC) Blue Cross Blue Shield Foundation (BCBS), worked with the South Carolina National Alliance on Mental Illness (NAMI) on a three-year evaluation of their ETS program. Results …

Deconvolving Provenance Signatures Of Pliocene-Pleistocene Coastal Loess Deposits Along The Atlantic Margin Of Argentina, Will Robert Quanrud

Theses and Dissertations

Dust derived from southern South America provides critical nutrients for autotropic marine biota in the South Atlantic Ocean, such that fluxes of wind-blown sediment may ultimately affect the concentration of atmospheric CO2. Expansive sand, silt, and loess deposits are exposed in Central Argentina, recording millions of years of eolian processes; however, the provenance and transport pathways of this dust remains unclear. Coastal loess deposits ranging in age from Pliocene to upper Pleistocene are present along the Atlantic margin of Argentina and provide information on sediment transport pathways for the last 4 million years. Nine samples of loess were collected and …

Uav-Based Tracking And Following Of Railroad Lines, Keith Michael Lewandowski

Theses and Dissertations

Given the pivotal role of the railroad industry in modern transportation and the potential risks associated with track malfunctions, the inspection and maintenance of railroad tracks emerges as a critical concern. While existing solutions excel in performing accurate measurements and detection, they often rely on large, expensive, and time-consuming platforms for inspections. This project, however, seeks to solve the same problem with the use of an unmanned aerial vehicle (UAV), significantly reducing time and cost while maintaining detection capabilities. In particular, this solution is ideal for large-scale, high-level inspections following major events such as floods [6], hurricanes [7] or earthquakes …