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Full-Text Articles in Physical Sciences and Mathematics

Advances In Deep Learning With Applications To Computer Vision And Astronomy, Zhihang Hu Aug 2021

Advances In Deep Learning With Applications To Computer Vision And Astronomy, Zhihang Hu

Dissertations

Deep Learning has spanned a variety of applications in computer vision as well as computational astronomy. These two aspects obtained similar data structure, therefore, their solutions can be transferable between each other. This dissertation look into two video-related tasks in computer vision and propose a novel problem in computational astronomy.

Specifically, acquiring an in-depth understanding of videos has been a cornerstone problem in computer vision. This problem has been studied by various researchers from different perspectives, among which video prediction has attracted much attention. Video prediction aims to generate the pixels of future frames given a sequence of context frames. …


Designing Collaborative Lifelogging To Facilitate Learning In Collaborative Physical-Recreation Communities, Sayed Mousa Ahmadi Olounabadi Aug 2021

Designing Collaborative Lifelogging To Facilitate Learning In Collaborative Physical-Recreation Communities, Sayed Mousa Ahmadi Olounabadi

Dissertations

Since the 1940s, researchers have envisioned lifelogging as the systematic capture and utilization of lived experiences for augmenting learning, performance, and community Unfortunately, this vision was never actualized since few, if any, systems support lifelogging in the term's original sense. Technologies that emerged through the Quantified-Self (QS) movement allowed users to monitor and track almost every life aspect. However, the decontextualized self-tracking data QS systems produced are unsuitable for supporting learning and community engagement, and therefore have not made lifelogging a reality yet. Central to this dissertation is understanding how to augment learning and community through lifelogging. This is particularly …


Analysis Of Container Throughput: Demand Forecast And Seaport Competitiveness Assessment, Hussain Talat Sulaimani Aug 2021

Analysis Of Container Throughput: Demand Forecast And Seaport Competitiveness Assessment, Hussain Talat Sulaimani

Dissertations

Seaports play a crucial role in the container industry, where they act as important nodes in the transport chain to facilitate international trade. In a competitive market, port capacity plays a significant role in defining its competitive position to attract demand and avoid congestion. Failing to provide suitable capacity results in the loss of market share. Therefore, port decision-makers face the challenge of maintaining and developing suitable port facilities to provide efficient services to port users. One of the aspects that decision-makers consider in the planning and development process is analyzing container demand. The analysis of container demand can be …


Synthesis And Characterization Of Novel Organic Ligands With Their Complexes Of Platinum, Copper And Uranium, Mustafa Adnan Yasin Aldulaimi Aug 2021

Synthesis And Characterization Of Novel Organic Ligands With Their Complexes Of Platinum, Copper And Uranium, Mustafa Adnan Yasin Aldulaimi

Dissertations

Transition metal complexes of symmetrical and asymmetrical Schiff bases have played a significant role in the field of coordination, inorganic, and bioinorganic chemistry as models for biological, analytical, industrial, and pharmaceutical applications. Over recent years a great deal of interest has developed in new transition metal complexes of Schiff base ligand. The preparation of novel organic ligands is the most important step in the development of metal complexes that exhibit unique properties and novel reactivity. To highlight the presentation of this dissertation and to provide more detailed investigations, the dissertation was separated into six chapters according to the sequence of …


Ensemble Data Fitting For Bathymetric Models Informed By Nominal Data, Samantha Zambo Aug 2021

Ensemble Data Fitting For Bathymetric Models Informed By Nominal Data, Samantha Zambo

Dissertations

Due to the difficulty and expense of collecting bathymetric data, modeling is the primary tool to produce detailed maps of the ocean floor. Current modeling practices typically utilize only one interpolator; the industry standard is splines-in-tension.

In this dissertation we introduce a new nominal-informed ensemble interpolator designed to improve modeling accuracy in regions of sparse data. The method is guided by a priori domain knowledge provided by artificially intelligent classifiers. We recast such geomorphological classifications, such as ‘seamount’ or ‘ridge’, as nominal data which we utilize as foundational shapes in an expanded ordinary least squares regression-based algorithm. To our knowledge …


Doping Of Conjugated Polymers: Preparation, Characterization And Device Fabrication, Kan Tang Aug 2021

Doping Of Conjugated Polymers: Preparation, Characterization And Device Fabrication, Kan Tang

Dissertations

Semiconducting conjugated polymers (CPs) as emerging materials for advanced electronic applications such as sensors, OPVs, and OEFTs has become an intriguing research topic in the past decades. It opens a new avenue of “flexible” electronics, which has shown great potential in next-generation electronic devices.

However, due to the nature of CP materials and related solution processing techniques, unlike almost perfectly crystalline silicon materials, CPs in the solid-state often exhibit much lower crystallinity if it is not complete amorphous, which severely hinder the electronic property and optical property of the materials. The crystallinity of CPs in a film is often uniquely …


Photopolymer Networks With Tunable Command Destruct Properties, William Walker Aug 2021

Photopolymer Networks With Tunable Command Destruct Properties, William Walker

Dissertations

Photoinduced thiol-catalyzed hydrogen abstraction and beta-scission of acyclic benzylidene acetals is demonstrated as a new route to “command-destruct” polymer thermosets. Using this approach, we show that poly(thioether acetal) networks synthesized via thiol-ene photopolymerization rapidly degrade to alkyl benzoate byproducts when triggered with light, transitioning from solid to liquid within seconds. The light-driven construction and destruction processes, accessible via distinct differences in kinetics, are readily amendable for photopatterning, additive/subtractive manufacturing, and wavelength-selective applications.

The first chapter of this dissertation details the development of command-destruct poly(thioether acetal) networks via a previously unexplored mechanism for polymer degradation. The degradation mechanism is confirmed via …


"Not In My Town": A Community's Response To Water And Soil Pollution, Karolina Staros Aug 2021

"Not In My Town": A Community's Response To Water And Soil Pollution, Karolina Staros

Dissertations

At the core of this dissertation is the acknowledgment that social movements are complex networks of people who face many obstacles in their efforts to achieve social change. One critique of social movements is that their goals and mission are limited to short term ideas and not long-term, systemic transformation. The lack of long term, systemic change can be observed when social movement groups mobilize for the same cause over and over again with what appears to be little progress over a period of time. The exact blueprint for a social movement’s success does not exist, but it is posited …


Understanding Potential Climate Change Impacts On Water Resources Within A Fractured Rock Watershed In Northern Togo, Mahawa-Essa Mabossani Akara Aug 2021

Understanding Potential Climate Change Impacts On Water Resources Within A Fractured Rock Watershed In Northern Togo, Mahawa-Essa Mabossani Akara

Dissertations

More than 72% of sub-Saharan Africa land surface is comprised of hard rock with fractured rock aquifers supplying water to an estimated 25% of the rural population. Given low porosity and storativity, fractured rock aquifers are particularly vulnerable to stresses such as projected population growth and climate variability. General circulation models of sub-Saharan Africa predict increases in temperature and in occurrences of extreme precipitation trends, such as flooding and drought. Adaptation strategies that promote optimal uses of water resources have emerged, although, most focus exclusively on surface water resources. This project investigates the potential impact of climate change on surface …


Computational Studies Of Carbon Nanocluster Solidification, Chathuri C. Silva Jul 2021

Computational Studies Of Carbon Nanocluster Solidification, Chathuri C. Silva

Dissertations

A subset of micron-size meteoritic carbon particles formed in red giant atmospheres show a core-rim structure, likely condensed from a vapor phase into super-cooled carbon droplets that nucleated graphene sheets (~40Å) on randomly oriented 5-atom loops during solidification, followed by coating with a graphite rim. Similar particles form during slow cooling of carbon vapor in the lab.

Here we investigate the nucleation and growth of carbon rings and graphene sheets using density functional theory (DFT). Our objectives: (1). explore different computational techniques in DFT-VASP for various carbon structures and compare the results with literature, (2). investigate the nucleation and growth …


Stereocontrolled Mannosylation By Hydrogen-Bond-Mediated Aglycone Delivery, Catherine Alex Jul 2021

Stereocontrolled Mannosylation By Hydrogen-Bond-Mediated Aglycone Delivery, Catherine Alex

Dissertations

Stereocontrolled Mannosylation by Hydrogen-Bond-Mediated Aglycone Delivery

Carbohydrates are the essential bio-molecules of life as they form the forefront of interactions with receptors, proteins, pathogens, or neighboring cells. On cell-surfaces, carbohydrates are mostly found as linear or branched glycoconjugates, and a majority of them are linked via either 1,2-cis or 1,2-trans O-glycosidic linkages. There is no template-driven pathway for achieving the synthesis of glycans unlike other biomolecules like proteins and nucleic acids. The synthesis of 1,2-trans glycosides can be reliably achieved via the neighboring group assistance. The synthesis of 1,2-cis glycosides is difficult because, beyond weak anomeric effects, there are …


Analysis Of The Primary Volatile Compositions In The Oort Cloud And Jupiter-Family Comets Towards The Goal Of Understanding Their Origin And Diversity, Mohammad Saki Jun 2021

Analysis Of The Primary Volatile Compositions In The Oort Cloud And Jupiter-Family Comets Towards The Goal Of Understanding Their Origin And Diversity, Mohammad Saki

Dissertations

Knowledge of the initial conditions present in the early solar nebula is required to understand the evolution and its current volatile content. Comets were some of the first objects to accrete in the solar nebula. They are among the most pristine (primitive) remnants of the solar system formation, and their present-day volatile composition likely reflects the composition and conditions where (and when) they formed. Therefore, they are fossils of the solar system formation. High-resolution near-infrared spectroscopy is a valuable tool for sampling the parent volatile (i.e., ices subliming directly from the nucleus) composition of comets via analysis of fluorescence emission …


Dominating Functions In Graphs, Maria Talanda-Fisher Jun 2021

Dominating Functions In Graphs, Maria Talanda-Fisher

Dissertations

Domination in graphs has become one of the most popular areas of graph the- ory, no doubt due to its many fascinating problems and applications to modern society, as well as the sheer mathematical beauty of the subject. While this area evidently began with the work by the French mathematician Claude Berge in 1958 and the Norwegian-American mathematician Oystein Ore in 1962, domination did not become an active area of research until 1977 with the appearance of the survey paper by Ernest Cockayne and Stephen Hedetniemi. Since then a large number of variations of domination have surfaced and provided numerous …


Novel Low Temperature Properties Of Filled And Unfilled Single Crystal Irsb3, Matthew Cook Jun 2021

Novel Low Temperature Properties Of Filled And Unfilled Single Crystal Irsb3, Matthew Cook

Dissertations

The skutterudite family of materials has garnered a lot of attention in the condensed matter community and it persists to be an important system for exploring the fundamental physics of solids. The initial interest into compounds with this common structure was due to their promising thermoelectric properties giving the possibility of efficient energy harvesting. Since, there has been a huge effort to systematically synthesize new filled skutterudite compounds, as nearly every type of strongly correlated behavior has been found within this family. As the field of topological materials has gained momentum, these materials have also been given a renewed interest …


Characterizing Undergraduate Students’ Proving Processes Around “Stuck Points”, Yaomingxin Lu Jun 2021

Characterizing Undergraduate Students’ Proving Processes Around “Stuck Points”, Yaomingxin Lu

Dissertations

Learning to prove mathematical propositions is a cornerstone of mathematics as a discipline (de Villiers, 1990). However, since proving is a different mathematical activity as compared to students’ prior experience, research has also shown that many undergraduate students struggle to learn to prove, including those who major in mathematics (Moore, 1994; Selden, 2012). While the field has generated research that has analyzed the final products of proof (Selden & Selden, 2009) and there are frameworks for analyzing problem-solving processes (e.g., Carlson & Bloom, 2005; Schoenfeld, 1985, 2010), much remains to be known about analyzing undergraduate students’ proving processes. With a …


Development Of A Decision Support System For Sustainable Water Planning In Abu Dhabi, Uae, Mohamed Ibrahim Kizhisseri Jun 2021

Development Of A Decision Support System For Sustainable Water Planning In Abu Dhabi, Uae, Mohamed Ibrahim Kizhisseri

Dissertations

One of the main challenges for water managers is to foresee the future accurately; then, design appropriate policies and infrastructure plans accordingly. The use of decision support systems in the field of water resource management and planning is now widely implemented, but its use in sustainable water planning of a nation or state in arid and semi-arid areas, such as Middle East countries, remains limited. The main objective of this dissertation is to present a graphical software tool that can assist water planners and decision-makers in long-term water management and planning. Sustainable planning for Abu Dhabi’s future water supply is …


Methods For Extending Biomedical Reference Ontologies And Interface Terminologies For Ehrr Text Annotation, Vipina Kuttichi Keloth May 2021

Methods For Extending Biomedical Reference Ontologies And Interface Terminologies For Ehrr Text Annotation, Vipina Kuttichi Keloth

Dissertations

Biomedical ontologies and terminologies are a cornerstone in various electronic health record systems (EHRs) for encoding information related to diseases, diagnoses, treatments, etc. Ontologies in general represent entities (concepts) and events along with all interdependent properties and relationships in an efficient way to facilitate easy access, retrieval and sharing. With the landscape of medicine rapidly changing, biomedical ontologies and terminologies need to rapidly evolve to support interoperability, medical coding, record keeping, and healthcare activities in general, and to facilitate interdisciplinary research. Extending ontologies by identifying new and missing concepts plays a vital role in the maintenance of ontologies to keep …


Reconstituting The Cyanobacterial Circadian Clock In Vitro, Pyong Hwa Kim May 2021

Reconstituting The Cyanobacterial Circadian Clock In Vitro, Pyong Hwa Kim

Dissertations

Cyanobacteria are photosynthetic organisms that are known to be responsible for oxygenating Earth’s early atmosphere. Having evolved to ensure optimal survival in the periodic light/dark cycle on this planet, their genetic codes are packed with various tools, including a sophisticated biological timekeeping system. Among the cyanobacteria is Synechococcus elongatus PCC 7942, the simplest clock-harboring organism with a powerful genetic tool that enabled the identification of its intricate timekeeping mechanism. The three central oscillator proteins—KaiA, KaiB, and KaiC—drive the 24 h cyclic gene expression rhythm of cyanobacteria, and the "ticking" of the oscillator can be reconstituted inside a test tube just …


Intermittent Dynamics Of Dense Particulate Matter, Chao Cheng May 2021

Intermittent Dynamics Of Dense Particulate Matter, Chao Cheng

Dissertations

Granular particle systems are scattered around the universe, and they can behave like solids when there exist strong force-bearing networks, so that the granular system can resist certain stress without deformation. When such a network is not present, particles yield to small stress and behave like a fluid. A wide range of systems exhibit intermittent dynamics as they are slowly loaded, with different dynamical regimes governing many industrial and natural phenomena. While a significant amount of research on exploring intermittent dynamics of granular systems has been carried out, not much is known about the connection between particle-scale response and the …


Radio Diagnostics Of Particles And Plasma In The Solar Corona, Sherry Chhabra May 2021

Radio Diagnostics Of Particles And Plasma In The Solar Corona, Sherry Chhabra

Dissertations

Radio diagnostics, in addition to their capabilities in exploring intense, impulsive bursts, also provide a high sensitivity to much weaker events, which may not show any substantial signature in other wavelengths.

The initial case study examines a complex event consisting of multiple radio sources/bursts associated with a fast coronal mass ejection (CME) and an M 2.1 class solar flare (SOL2015-09-20). ‘First-light’ data from the Owens Valley Radio Observatory–Long Wavelength Array is put in context with observations from Large Angle and Spectrometric Coronagraph onboard the Solar and Heliospheric Observatory, along with the WAVES radio spectrograph onboard WIND, the Expanded Owens Valley …


Development Of Deep Learning Neural Network For Ecological And Medical Images, Shaobo Liu May 2021

Development Of Deep Learning Neural Network For Ecological And Medical Images, Shaobo Liu

Dissertations

Deep learning in computer vision and image processing has attracted attentions from various fields including ecology and medical image. Ecologists are interested in finding an effective model structure to classify different species. Tradition deep learning model use a convolutional neural network, such as LeNet, AlexNet, VGG models, residual neural network, and inception models, are first used on classifying bee wing and butterfly datasets. However, insufficient data sample and unbalanced samples in each class have caused a poor accuracy. To make improvement the test accuracy, data augmentation and transfer learning are applied. Recently developed deep learning framework based on mathematical morphology …


Safe Yield Comparisons For The 1960’S And 2000’S Drought In The Passaic River Basin, Stephanie R. Santos May 2021

Safe Yield Comparisons For The 1960’S And 2000’S Drought In The Passaic River Basin, Stephanie R. Santos

Dissertations

The Passaic River Basin is a complex system of rivers, tributaries, reservoirs, and some of the largest water purveyors in the State of New Jersey. Located in the northeastern part of the State, it drains approximately 800 square miles of water that is used for distribution to the five major purveyors: North Jersey District Water Supply Commission, Passaic Valley Water Commission, Jersey City, Newark, and New Jersey American Water. These purveyors operate under a safe yield, which is defined by the New Jersey Department of Environmental Protection (NJDEP) as the amount of water that should be continuously available should the …


First-Principles Density Functional Theory Studies On Perovskite Materials, Aneer Lamichhane May 2021

First-Principles Density Functional Theory Studies On Perovskite Materials, Aneer Lamichhane

Dissertations

Perovskites are a family of materials with a diverse combination of different elements. As a consequence, they exhibit numerous functionalities such as pyroelectric, piezoelectric, ferroelectric, and ferromagnetic with applications in photovoltaic cells, LEDs, superconductivity, colossal magneto-resistance, and topological insulators. After 2009, perovskites have gained notoriety as suitable materials for solar cells and alternative candidates to silicon-based conventional solar cells. Generally, oxide perovskites exhibit good dielectric properties, halide perovskites display good photonic qualities, and chalcogenide perovskites are used in applications in solid-state lighting, sensing, and energy harvesting. In this dissertation, various types of perovskites ranging from oxide to halide are investigated …


Optimizing Work Zone Schedules Considering Traffic Diversion With Artificial Bee Colony Algorithm, Celina Semaan May 2021

Optimizing Work Zone Schedules Considering Traffic Diversion With Artificial Bee Colony Algorithm, Celina Semaan

Dissertations

Highway maintenance activities often decrease roadway capacity and intrude traffic movements. The need to finish the project on time and under a specific budget while minimizing the traffic congestion and complying with the emission standards requires an appropriate work zone schedule optimization. The objective of this research is to improve the efficiency of work zone activities and minimize the total project cost including maintenance, user, and emission cost.

While previous studies investigated the work zone optimization problem, they did not consider the implementation of emission standards nor applied a green diversion strategy. This dissertation analyzes the optimization of work zone …


Intelligent And Secure Fog-Aided Internet Of Drones, Jingjing Yao May 2021

Intelligent And Secure Fog-Aided Internet Of Drones, Jingjing Yao

Dissertations

Internet of drones (IoD), which utilize drones as Internet of Things (IoT) devices, deploys several drones in the air to collect ground information and send them to the IoD gateway for further processing. Computing tasks are usually offloaded to the cloud data center for intensive processing. However, many IoD applications require real-time processing and event response (e.g., disaster response and virtual reality applications). Hence, data processing by the remote cloud may not satisfy the strict latency requirement. Fog computing attaches fog nodes, which are equipped with computing, storage and networking resources, to IoD gateways to assume a substantial amount of …


Impact Of User Traversal On Performance Of Stem Learners In Immersive Virtual Environments, Eric W. Nersesian May 2021

Impact Of User Traversal On Performance Of Stem Learners In Immersive Virtual Environments, Eric W. Nersesian

Dissertations

The emerging technologies of augmented and virtual reality (AR/VR) may have vast implications to societal communication and representation of information. AR/VR computer interfaces are unique in that they may be placed spatially around the user in three-dimensional (3D) space; this affords new methods of both presentation and user interaction with the target information.

This may be especially impactful in the education of science, technology, engineering, and mathematics (STEM) professionals. Prior research has shown that simulations and visualizations improve the performance of STEM learners compared to live instruction and textbook reading. Yet, research into AR/VR as a learning environment for widespread …


Deep Learning On Image Forensics And Anti-Forensics, Zhangyi Shen May 2021

Deep Learning On Image Forensics And Anti-Forensics, Zhangyi Shen

Dissertations

Image forensics protect the authenticity and integrity of digital images. On the contrary, as the countermeasures of digital forensics, anti-forensics is applied to expose the vulnerability of forensics tools. Consequently, forensics researchers could develop forensics tools against possible new attacks. This dissertation investigation demonstrates two image forensics methods based on convolutional neural network (CNN) and two image anti-forensics methods based on generative adversarial network (GAN).

Detecting unsharp masking (USM) sharpened image is the first study in this dissertation. A CNN architecture comprises four convolutional layers and a classification module is proposed to discriminate sharpened images and unsharpened images. The results …


Eigenvalue Problems For Fully Nonlinear Elliptic Partial Differential Equations With Transport Boundary Conditions, Jacob Lesniewski May 2021

Eigenvalue Problems For Fully Nonlinear Elliptic Partial Differential Equations With Transport Boundary Conditions, Jacob Lesniewski

Dissertations

Fully nonlinear elliptic partial differential equations (PDEs) arise in a number of applications. From mathematical finance to astrophysics, there is a great deal of interest in solving them. Eigenvalue problems for fully nonlinear PDEs with transport boundary conditions are of particular interest as alternative formulations of PDEs that require data to satisfy a solvability condition, which may not be known explicitly or may be polluted by noisy data. Nevertheless, these have not yet been well-explored in the literature. In this dissertation, a convergence framework for numerically solving eigenvalue problems for fully nonlinear PDEs is introduced. In addition, existing two-dimensional methods …


Global Mhd And Acoustic Solar Modeling And Helioseismic Analysis, Andrey M. Stejko May 2021

Global Mhd And Acoustic Solar Modeling And Helioseismic Analysis, Andrey M. Stejko

Dissertations

Computational fluid dynamic simulations have become one of the most prolific avenues of study in the fields of solar and stellar physics within the last several decades. With the advent of ever increasing computing power, high-definition global models of the Sun have become indispensable in understanding the complex and chaotic nature of flows in the solar interior, as well as their impact on the evolution of the global solar dynamo. The mechanisms that connect the generation of the toroidal magnetic field at the base of the convection zone to the emergence of a poloidal field onto the solar surface can …


Asymmetric Multivariate Archimedean Copula Models And Semi-Competing Risks Data Analysis, Ziyan Guo May 2021

Asymmetric Multivariate Archimedean Copula Models And Semi-Competing Risks Data Analysis, Ziyan Guo

Dissertations

Many multivariate models have been proposed and developed to model high dimensional data when the dimension of a data set is greater than 2 (d ≥ 3). The existing multivariate models often force the “exchangeable” structure for part or the whole model, are not very flexible which tends to be of limited use in practice. There is a demand for developing and studying multivariate models with any pre-specified bivariate margins.

Suppose there exists such a class of flexible models with any pre-specified bivariate margins. Given a multivariate data, what is the distribution function and how to easily estimate the parameters …