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Full-Text Articles in Physical Sciences and Mathematics

Detrital Composition Of Triassic To Neogene Sandstones In The Sulaiman Fold-Thrust Belt, Pakistan: Implications For Pre- And Postcollisional Evolution Of The Northwestern Indian Margin, Shazia Fareed, Akhtar Kassi, Aimal Kasi, Namik Aysal Jan 2022

Detrital Composition Of Triassic To Neogene Sandstones In The Sulaiman Fold-Thrust Belt, Pakistan: Implications For Pre- And Postcollisional Evolution Of The Northwestern Indian Margin, Shazia Fareed, Akhtar Kassi, Aimal Kasi, Namik Aysal

Turkish Journal of Earth Sciences

Sandstones of the Triassic through Pliocene successions of the western Sulaiman Fold-Thrust Belt (SFTB), Pakistan, were studied, by polarizing microscope and using point-counting techniques, to determine systematic variations in detrital modes. The sandstones in the study area are categorized into pre- and postcollisional sandstone assemblages. The precollisional assemblage was deposited before the onset of collision of India with Eurasia (starting Late Cretaceous-Early Paleocene) and subcategorized as Wulgai- Mughal Kot, Bibai and Pab subassemblages. The postcollisional assemblage was deposited after the onset of collision and categorized as Ghazij and Urak subassemblages. The Wulgai-Mughal Kot subassemblage mostly comprises of highly quartzose sandstones …


Relative Tectonic Activity Assessment Of Kütahya Graben (Western Anatolia): Insights From Geomorphic Indices, Zeynep Kezer, Erman Özsayin Jan 2022

Relative Tectonic Activity Assessment Of Kütahya Graben (Western Anatolia): Insights From Geomorphic Indices, Zeynep Kezer, Erman Özsayin

Turkish Journal of Earth Sciences

Western Anatolia is known as one of the most seismically active regions in the world, consistent with earthquakes having a magnitude >6.0. The deformation in the region is predominantly controlled by normal faults, which play significant role on the morphological features as well as depositional processes in related grabens. WNW-trending Kütahya Graben is located at the northeastern part of this province and bounded by several N- and S-dipping active normal fault segments. This study aims to investigate the relative tectonic activity among the fault segments of the Kütahya Graben using geomorphic indices. The analyses of this study include mountain-front sinuosity …


Late Ediacaran Inertial-Interchange True Polar Wander (Iitpw) Event: A New Road To Reconcile The Enigmatic Paleogeography Prior To The Final Assembly Of Gondwana, Bin Wen, Cairong Luo, Yong-Xiang Li, Yanting Lin Jan 2022

Late Ediacaran Inertial-Interchange True Polar Wander (Iitpw) Event: A New Road To Reconcile The Enigmatic Paleogeography Prior To The Final Assembly Of Gondwana, Bin Wen, Cairong Luo, Yong-Xiang Li, Yanting Lin

Turkish Journal of Earth Sciences

The Ediacaran to Early Cambrian plate tectonics was dominated by a full dispersal of the supercontinent Rodinia and the subsequent amalgamation of Gondwana. There is a consensus that the final assembly of Gondwana was not completed until the Early Cambrian. Prior to the final assembly, however, one major uncertainty remains on the quantitative paleogeography: the mainland of Gondwana was plausibly positioned at either a high or low latitude at a single time instant to meet the dual-latitude ('high-latitude' and 'low-latitude') options of Laurentia and the requirement of


A Preliminary Account On Devonian Trilobites From Arabian Plate, Se Turkey, Catherine Cronier, İzzet Hoşgör Jan 2022

A Preliminary Account On Devonian Trilobites From Arabian Plate, Se Turkey, Catherine Cronier, İzzet Hoşgör

Turkish Journal of Earth Sciences

Recently, several Devonian localities and the related biota occurring from the southeastern Turkey were reinvestigated. Although, the Hakkari-Çukurca and the Diyarbakır-Hazro areas of the Arabian Plate are considered as an important source of the Devonian macrofossils from the north Arabian sector of Gondwana, the existing record of Devonian trilobites in these regions was hitherto unknown. We here report and illustrate for the first time Lower and Middle Devonian trilobites represented by three proetid pygidia and one calymenid pygidium. The morphological features of these pygidia suggest that they can be assigned to undetermined species of Gravicalymene (Calymenidae) and Podoliproetus (Proetidae), two …


Nature And Crystallization Stages Of Spherulites Within The Obsidian: Acıgöl (Cappadocia- Nevşehir, Turkey), Bahatti̇n Güllü, Kiymet Deni̇z Jan 2022

Nature And Crystallization Stages Of Spherulites Within The Obsidian: Acıgöl (Cappadocia- Nevşehir, Turkey), Bahatti̇n Güllü, Kiymet Deni̇z

Turkish Journal of Earth Sciences

The study area comprises a part of the Central Anatolian Cenozoic volcanism within the Cappadocia Volcanic Province (CVP). Obsidian, perlite rhyolite flows, and volcanic ashes are observed in the study area and the spherulites within the obsidian are the objects of this study. The spherulites occupied within the obsidian in the form of round nodules 0.5-10 cm in diameter. The confocal Raman spectra of feldspar minerals within the spherulites are characterized by T-O-T and M-O lattice modes in the range of 100-250 cm-1, O-T-O deformation and T-O-T lattice modes in the range of 250-350 cm-1, and …


Analysis, Processing, And Migration Of The Marine 4-Component Walkaway Vsp Data Set From The Seg Seam-1 Gulf Of Mexico Salt Elastic Modelling Project: Synthetic Study, Cemal Erdemi̇r Jan 2022

Analysis, Processing, And Migration Of The Marine 4-Component Walkaway Vsp Data Set From The Seg Seam-1 Gulf Of Mexico Salt Elastic Modelling Project: Synthetic Study, Cemal Erdemi̇r

Turkish Journal of Earth Sciences

The four component (4C) walkaway vertical seismic profile (WVSP) marine elastic synthetic data set from the SEG's SEAM-1 salt modeling project in the Gulf of Mexico (GOM) are examined, analyzed, processed, and migrated for P-P reflections using a reverse time prestack migration (RTM) algorithm to construct a subsurface image around the Well-1 VSP borehole. The imaging results from the three data sets; pressure-p, geophone vertical (z), and horizontal inline (x) components, have shown great successes in correctly locating and imaging sediments near and below the borehole as well as the vertical face of the salt, which is about 5 km …


Vertical Variations Of Minerals In Clayey Sedimentary Rocks In The Cores Of Two-Deep Exploration Wells From The Kozlu Coalfield (Zonguldak, Nw Türkiye), With Emphasis On Tonstein (Schieferton) Formation, Ali̇ İhsan Karayi̇ği̇t, Emi̇ne Sütcü, Abi̇di̇n Temel, Mustafa Ni̇yazi̇ Gündoğdu Jan 2022

Vertical Variations Of Minerals In Clayey Sedimentary Rocks In The Cores Of Two-Deep Exploration Wells From The Kozlu Coalfield (Zonguldak, Nw Türkiye), With Emphasis On Tonstein (Schieferton) Formation, Ali̇ İhsan Karayi̇ği̇t, Emi̇ne Sütcü, Abi̇di̇n Temel, Mustafa Ni̇yazi̇ Gündoğdu

Turkish Journal of Earth Sciences

The majority of Turkish bituminous coal resources are located in the Zonguldak Basin. The Carboniferous coal seams in the Alacaağzı, Kozlu, and Karadon formations have received interest. However, the detailed mineralogical compositions of clayey sedimentary rocks in coal-bearing sequences in the basin have been limited. This study aims to investigate vertical variations of mineralogical compositions of Carboniferous and Early Cretaceous clayey sedimentary rocks cored in the two-deep exploration wells (K20/K and K20/H) from the Kozlu coalfield using XRD and SEM-EDX analyses data. In addition, a special interest is also given to tonstein layers identified within the Kozlu and Karadon formations. …


A Historical Analysis Of The U.S. Federal Emergency Management Agencies (Fema) Response And Recovery To Gulf Coast Hurricane And Other Weather-Related Disasters, Lauren Marie Denning Jan 2022

A Historical Analysis Of The U.S. Federal Emergency Management Agencies (Fema) Response And Recovery To Gulf Coast Hurricane And Other Weather-Related Disasters, Lauren Marie Denning

Graduate Research Papers

The growing changes in our environment combined with the increased number of catastrophic climate and weather- related events are occurring more frequently and continuing to intensify in the United States and Worldwide. These events are resulting in mass destruction in our environment and infrastructure, significant loss in human lives, and costing billions of dollars in response and recovery. Although there is no way to prevent these events, governments and populations can take steps to adapt and prepare for these events. This will ultimately decrease the overall impacts that these events have on our environment and future generations to come.

This …


Non-Chromatographic Oligonucleotide Purification And Automated Polyethyleneglycol Synthesis, Dhananjani N. A. M. Eriyagama Jan 2022

Non-Chromatographic Oligonucleotide Purification And Automated Polyethyleneglycol Synthesis, Dhananjani N. A. M. Eriyagama

Dissertations, Master's Theses and Master's Reports

Synthetic oligodeoxynucleotides (ODN) have various applications in many areas such as, synthetic biology, chemical biology, antisense drug development, and data storage. As a result, there is a high demand for synthetic ODNs. Many advances have been made with ODN synthesis the purification still remains a bottleneck. The non-chromatographic purification method is developed to address this problem. Similarly, polyethylene glycols (PEGs) have been used in many areas including pharmaceutical applications, surface science, and nanomedicine due to its unique properties. However, monodispersed PEG synthesis is expensive with existing methods. A novel automated solid phase synthesis method is developed to obtain monodispersed PEGs. …


Free Energies For Nonlinear Materials With Memory, John Murrough Golden Jan 2022

Free Energies For Nonlinear Materials With Memory, John Murrough Golden

Articles

An exploration of representations of free energies and associated rates of dissipation for a broad class of nonlinear viscoelastic materials is presented in this work. Also included are expressions for the stress functions and work functions derivable from such free energies. For simplicity, only the scalar case is considered. Certain standard formulae are generalized to include higher power terms.

It is shown that the correct initial procedure in this context is to specify the rate of dissipation as a positive semi-definite functional and then to determine the free energy from this, rather than the other way around, which would be …


Mathematical Analysis Of The Van Der Waals Equation, Emil Prodanov Jan 2022

Mathematical Analysis Of The Van Der Waals Equation, Emil Prodanov

Articles

The parametric cubic van der Waals polynomial $p V^3 - (R T + b p) V^2 + a V - a b$ is analysed mathematically and some new generic features (theoretically, for any substance) are revealed: the temperature range for applicability of the van der Waals equation, $T > a/(4Rb)$, and the isolation intervals, at any given temperature between $a/(4Rb)$ and the critical temperature $8a/(27Rb)$, of the three volumes on the isobar--isotherm: $3b/2 < V_A \le 3b$, $ 2b < V_B < 4b/(3 - \sqrt{5})$, and $3b < V_C < b + RT/p$. The unstable states of the van der Waals model have also been generically localized: they lie in an interval within the isolation interval of $V_B$. In the case of unique intersection point of an isotherm with an isobar, the isolation interval of this unique volume is also determined. A discussion on finding the volumes $V_{A, B, C}$, on the premise of Maxwell's hypothesis, is also presented.


On-Ice Detection, Classification, Localization And Tracking Of Anthropogenic Acoustic Sources With Machine Learning, Steven J. Whitaker Jan 2022

On-Ice Detection, Classification, Localization And Tracking Of Anthropogenic Acoustic Sources With Machine Learning, Steven J. Whitaker

Dissertations, Master's Theses and Master's Reports

Arctic acoustics have been of concern in recent years for the US navy. First-year ice is now the prevalent factor in ice coverage in the Arctic, which changes the previously understood acoustic properties. Due to the ice melting each year, anthropogenic sources in the Arctic region are more common: military exercises, shipping, and tourism. For the navy, it is of interest to detect, classify, localize, and track these sources to have situational awareness of these surroundings. Because the sources are on-water or on-ice, acoustic radiation propagates at a longer distance and so acoustics are the method by which the sources …


Defining The Endmember System Of Us Soils And Quantifying Relationships, And A Hyperspectral Approach To The Alteration Strength Index, Rachel Rulison Jan 2022

Defining The Endmember System Of Us Soils And Quantifying Relationships, And A Hyperspectral Approach To The Alteration Strength Index, Rachel Rulison

Dissertations, Master's Theses and Master's Reports

Soils form a complex part of the environment, providing important functions in systems such as food production, groundwater movement, and ecosystem health. There have been numerous studies on soil geochemistry and the origin of elements within soils, but few studies into quantifying the relationships between elements and geographical data on a national scale. Using geochemical data obtained by the USGS, the surficial soils of the US were defined by a 13-endmember system using Polytopic Vector Analysis and mapped in GIS. Correlation matrices provided Pearson’s correlation coefficients for elements in the Top 5 cm soil profile, the A horizon, and the …


Multilevel Computational Investigation Into The Dynamics And Reaction Mechanisms Of Non-Heme Iron And 2-Oxoglutarate Dependent Enzymes, Shobhit Sanjeev Chaturvedi Jan 2022

Multilevel Computational Investigation Into The Dynamics And Reaction Mechanisms Of Non-Heme Iron And 2-Oxoglutarate Dependent Enzymes, Shobhit Sanjeev Chaturvedi

Dissertations, Master's Theses and Master's Reports

Computational chemistry methods have been extensively applied to investigate biological systems. This dissertation utilizes a multilevel computational approach to explore the dynamics and reaction mechanisms of two groups of enzymes belonging to non-heme Fe(II) and 2-oxoglutarate (2OG) dependent superfamily – histone lysine demethylases from class 7 and ethylene forming enzyme (EFE). Chapter 2 uncovers the role of conformational dynamics in the substrate selectivity of histone lysine demethylases 7A and 7B. The molecular dynamics (MD) simulations of the two enzymes revealed the importance of linker flexibility and dynamics in relative orientations of the reader (PHD) and the catalytic (JmjC) domains. Chapter …


A Surrogate Model Of Molecular Dynamics Simulations For Polar Fluids: Supervised Learning Methods For Molecular Polarization And Unsupervised Methods For Phase Classification, Zackerie W. Hjorth Jan 2022

A Surrogate Model Of Molecular Dynamics Simulations For Polar Fluids: Supervised Learning Methods For Molecular Polarization And Unsupervised Methods For Phase Classification, Zackerie W. Hjorth

Dissertations, Master's Theses and Master's Reports

Molecular Dynamic (MD) simulation is a standard computational tool in soft matter physics. While very powerful, it is computationally expensive, leading to some simulations taking days or even weeks to complete depending on the size of your computer cluster. Finding computationally cheap surrogate models which can learn the output features of MD simulation is therefore highly motivated. In this report I explore the use of deep neural network ensembles as well as support vector machine regressors as surrogate models for MD simulation. From the output of the surrogate models, we can then employ unsupervised learning methods to get insight into …


A Combined Spectral And Energy Morphology Analysis Of Gamma Ray Source Hawc J2031+415 In The Cygnus Constellation, Ian Herzog Jan 2022

A Combined Spectral And Energy Morphology Analysis Of Gamma Ray Source Hawc J2031+415 In The Cygnus Constellation, Ian Herzog

Dissertations, Master's Theses and Master's Reports

HAWC J2031+415 is a probable pulsar wind nebula (PWN) located in the Cygnus Cocoon region near a complex OB star cluster. First observed by the High-Energy-Gamma-Ray Astronomy (HEGRA) observatory in the TeV energy regime, the source had no apparent counterpart in lower energy ranges. Previous work using 1343 days of data from the High-Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory has determined that three sources are present in the Region of Interest (ROI): HAWC J2031+415, HAWC J2030+409 (also known as the Cocoon), and 3HWC J2020+403 (associated with the Gamma Cygni supernova remnant) \cite{Ian_01, Binita_01}.

In this work, I use the newest …


Chromatography-Mass Spectroscopy Analysis Of Native American Pottery For Maple Syrup Residues, Alexis Wirtz Jan 2022

Chromatography-Mass Spectroscopy Analysis Of Native American Pottery For Maple Syrup Residues, Alexis Wirtz

Honors Program Theses

The research conducted regards whether or not Native Americans understood how to create maple syrup before the influence of Europeans. The analytical technique that was used is gas chromatography-mass spectrometry (GC-MS). This technique assisted in understanding what organic residues resided within the pottery and what those organic residues tell us about Native American history. An analysis of organic residues was performed on the following types of pottery: proof of concept pottery, weathered pottery (an analog of the proof of concept), and Native American pottery. The residues used in analysis were obtained through the usage of different solvent systems - Acetone: …


Fine Scale Mapping Of Laurentian Mixed Forest Natural Habitat Communities Using Multispectral Naip And Uav Datasets Combined With Machine Learning Methods, Parth P. Bhatt Jan 2022

Fine Scale Mapping Of Laurentian Mixed Forest Natural Habitat Communities Using Multispectral Naip And Uav Datasets Combined With Machine Learning Methods, Parth P. Bhatt

Dissertations, Master's Theses and Master's Reports

Natural habitat communities are an important element of any forest ecosystem. Mapping and monitoring Laurentian Mixed Forest natural communities using high spatial resolution imagery is vital for management and conservation purposes. This study developed integrated spatial, spectral and Machine Learning (ML) approaches for mapping complex vegetation communities. The study utilized ultra-high and high spatial resolution National Agriculture Imagery Program (NAIP) and Unmanned Aerial Vehicle (UAV) datasets, and Digital Elevation Model (DEM). Complex natural vegetation community habitats in the Laurentian Mixed Forest of the Upper Midwest. A detailed workflow is presented to effectively process UAV imageries in a dense forest environment …


Development Of A Computational Application To Aid With Chemometric And Forensic Analysis Of Fire Debris Samples, Michelle Corbally Jan 2022

Development Of A Computational Application To Aid With Chemometric And Forensic Analysis Of Fire Debris Samples, Michelle Corbally

Electronic Theses and Dissertations, 2020-2023

Fire debris analysis is a forensic science discipline that determines if an ignitable liquid residue is present or absent in a fire debris sample. Currently, fire debris analysis results in categorical statements based on qualitative data, not the quantitative evidentiary value of data. The purpose of this research was to develop a novel software application to aid fire debris analysts in the identification and classification of ignitable liquid residues that are found in fire debris samples. The developed application uses target factor analysis (TFA) and Pearson correlation for compound identification in gas chromatograms using mass spectral comparison and allows for …


Characterizing The Particle Size Distribution In Saturn's Rings Using Cassini Uvis Stellar Occultation Data, Stephanie Eckert Jan 2022

Characterizing The Particle Size Distribution In Saturn's Rings Using Cassini Uvis Stellar Occultation Data, Stephanie Eckert

Electronic Theses and Dissertations, 2020-2023

NASA's Cassini mission to Saturn revolutionized modern understanding of the planet's vast and intricate ring system. We use stellar occultation data from Cassini's UVIS High Speed Photometer (HSP) to characterize the particle size distribution in the rings with two methods. First, we discern the sizes of the smallest particles at ring edges by forward-modeling observed diffraction signatures which appear as spikes in the signal, the shape and amplitude of which depends on the size and abundance of the smallest particles. We then probe the upper end of the size distribution using occultation statistics. Although the distribution of photon counts in …


Towards Automated Data Mining: Reinforcement Intelligence For Self-Optimizing Feature Engineering, Kunpeng Liu Jan 2022

Towards Automated Data Mining: Reinforcement Intelligence For Self-Optimizing Feature Engineering, Kunpeng Liu

Electronic Theses and Dissertations, 2020-2023

Feature engineering is one of the most important components in data mining and machine learning. One of the key thrusts in data mining is to answer: How should a low-dimensional geometry structure be extracted and reconstructed from high-dimensional data? To solve this issue, researchers proposed feature selection, PCA, sparsity regularization, factorization, embedding, and deep learning. However, existing techniques are limited in achieving full automation, globally optimal, and explainable explicitness. Can I address the automation, optimal, and explainability challenges in data geometry reconstruction? A low-dimensional data geometry structure is crucial for SciML methods (e.g., GP models), and the accuracy of these …


Balancing User Experience For Mobile One-To-One Interpersonal Telepresence, Kevin Pfeil Jan 2022

Balancing User Experience For Mobile One-To-One Interpersonal Telepresence, Kevin Pfeil

Electronic Theses and Dissertations, 2020-2023

The COVID-19 virus disrupted all aspects of our daily lives, and though the world is finally returning to normalcy, the pandemic has shown us how ill-prepared we are to support social interactions when expected to remain socially distant. Family members missed major life events of their loved ones; face-to-face interactions were replaced with video chat; and the technologies used to facilitate interim social interactions caused an increase in depression, stress, and burn-out. It is clear that we need better solutions to address these issues, and one avenue showing promise is that of Interpersonal Telepresence. Interpersonal Telepresence is an interaction paradigm …


Testing The Influence Of Water Depth In Design Of Created Oyster Reef For Living Shoreline Applications, Peter Vien Jan 2022

Testing The Influence Of Water Depth In Design Of Created Oyster Reef For Living Shoreline Applications, Peter Vien

Electronic Theses and Dissertations, 2020-2023

Living shoreline stabilization has become a popular practice in shoreline restoration and bank protection; however, there are still many uncertainties regarding effective site design using living materials. For example, natural wave-breaks may be formed of created reefs, but the optimum water depth for hydrodynamic influence may differ from the preferred depth to ensure organism recruitment. The objective of this research is to understand how water depth relative to the crest of submerged artificial oyster reef structures influences nearshore hydrodynamic processes and sediment transport or retention in nearshore areas. A field study, sited in a microtidal estuary on the Atlantic coast …


Computational Methods To Analyze Next-Generation Sequencing Data In Genomics And Metagenomics, Saidi Wang Jan 2022

Computational Methods To Analyze Next-Generation Sequencing Data In Genomics And Metagenomics, Saidi Wang

Electronic Theses and Dissertations, 2020-2023

This thesis focuses on two important computational problems in genomics and metagenomics with the public available next-generation sequencing data. One is about gene regulation, for which we explore how distal regulatory elements may interact with the proximal regulatory elements. The other is about metagenomics, in which we study how to reconstruct bacterial strain genomes from shotgun reads. Studying gene regulation, especially distal gene regulation, is important because regulatory elements, including those in distal regulatory regions, orchestrate when, where and how much a gene is activated under every experimental condition. Their dysfunction results in various types of diseases. Moreover, the current …


Quantum Graph Parameters, Parisa Darbari Kozekanan Jan 2022

Quantum Graph Parameters, Parisa Darbari Kozekanan

Electronic Theses and Dissertations, 2020-2023

This dissertation considers some of the advantages, and limits, of applying quantum computing to solve two important graph problems. The first is estimating a graph's quantum chromatic number. The quantum chromatic number is the minimum number of colors necessary in a two-player game where the players cannot communicate but share an entangled state and must convince a referee with probability one that they have a proper vertex coloring. We establish several spectral lower bounds for the quantum chromatic number. These lower bounds extend the well-known Hoffman lower bound for the classical chromatic number. The second is the Pattern Matching on …


Change Point Detection For Streaming Data Using Support Vector Methods, Charles Harrison Jan 2022

Change Point Detection For Streaming Data Using Support Vector Methods, Charles Harrison

Electronic Theses and Dissertations, 2020-2023

Sequential multiple change point detection concerns the identification of multiple points in time where the systematic behavior of a statistical process changes. A special case of this problem, called online anomaly detection, occurs when the goal is to detect the first change and then signal an alert to an analyst for further investigation. This dissertation concerns the use of methods based on kernel functions and support vectors to detect changes. A variety of support vector-based methods are considered, but the primary focus concerns Least Squares Support Vector Data Description (LS-SVDD). LS-SVDD constructs a hypersphere in a kernel space to bound …


Distance Perception Through Head-Mounted Displays, Sina Masnadi Jan 2022

Distance Perception Through Head-Mounted Displays, Sina Masnadi

Electronic Theses and Dissertations, 2020-2023

It has been shown in numerous research studies that people tend to underestimate distances while wearing head-mounted displays (HMDs). We investigated various possible factors affecting the perception of distance is HMDs through multiple studies. Many contributing factors has been identified by researchers in the past decades, however, further investigation is required to provide a better understanding of this problem. In order to find a baseline for distance underestimation, we performed a study to compare the distance perception in real world versus a fake headset versus a see-through HMD. Users underestimated distances while wearing the fake headset or the see-through HMD. …


Methods For Defending Neural Networks Against Adversarial Attacks, Sharvil Shah Jan 2022

Methods For Defending Neural Networks Against Adversarial Attacks, Sharvil Shah

Electronic Theses and Dissertations, 2020-2023

Convolutional Neural Networks (CNNs) have been at the frontier of the revolution within the field of computer vision. Since the advent of AlexNet in 2012, neural networks with CNN architectures have surpassed human-level capabilities for many cognitive tasks. As the neural networks are integrated in many safety critical applications such as autonomous vehicles, it is critical that they are robust and resilient to errors. Unfortunately, it has recently been observed that deep neural network models are susceptible to adversarial perturbations which are imperceptible to human vision. In this thesis, we propose a solution to defend neural networks against white box …


Towards Leveraging Sparse Infrared Datasets For Multiple View Synthesis, Few Shot Learning And Background Invariant Recognition, Maliha Arif Jan 2022

Towards Leveraging Sparse Infrared Datasets For Multiple View Synthesis, Few Shot Learning And Background Invariant Recognition, Maliha Arif

Electronic Theses and Dissertations, 2020-2023

This dissertation presents a study of various machine learning techniques for recognizing vehicular objects in infrared images. State of the art methods for computer vision have not been widely explored for this part of the electromagnetic spectrum (EM). Challenges that arise due to the dearth of infrared training images, terrain clutter, and thermal phenomenology have not been fully addressed. Infrared dataset collection and annotation is both difficult and expensive. What if there is a way we can generate infrared images and diminish the need for collecting data out in the field? Our first research study encompasses an encoder-decoder model that …


Identifying Challenges And Opportunities For Designing Social Media Nudges For Adolescents, Oluwatomisin Obajemu Jan 2022

Identifying Challenges And Opportunities For Designing Social Media Nudges For Adolescents, Oluwatomisin Obajemu

Electronic Theses and Dissertations, 2020-2023

With the prevalence of online risks encountered by youth online, strength-based approaches such as nudges have been recommended as a potential solution to subtly guide teens toward safer decisions. However, most nudging interventions to date have not been designed to cater to teens’ unique needs and online safety concerns. To address this gap, this study aimed to better understand adolescents’ perceptions and feedback on online safety nudges to inform the design of more effective online safety interventions. We conducted 12 semi-structured interviews and 3 focus group sessions with 21 teens (13 – 17 years old) to get their feedback on …