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Full-Text Articles in Physical Sciences and Mathematics

N-Heterocyclic Carbene Ligated Group 11 Trimethylsilylchalcogenolates: Building Blocks For Heterometallic Chalcogenide Molecules, Dickron Richard Nahhas Apr 2020

N-Heterocyclic Carbene Ligated Group 11 Trimethylsilylchalcogenolates: Building Blocks For Heterometallic Chalcogenide Molecules, Dickron Richard Nahhas

Electronic Thesis and Dissertation Repository

The synthesis of heterometallic chalcogenide molecules requires the continued investigation into the appropriate reagents necessary to introduce metal – chalcogen bonds in a controlled fashion. Trimethylsilyl metallochalcogenolates (MESiMe3) act as synthons introducing “ME“ in solution upon reacting with an appropriate ternary metal reagent, MX (X= halide, acetate, etc.). Recent work makes use of N–heterocyclic carbenes (NHCs) as a class of ancillary ligand that can stabilize these reagents and the heterometallic chalcogenide molecules obtained with them. Building on previous work, this thesis describes the synthesis of group 11 trimethylsilyl metallochalcogenolates stabilized by bis–1,3–tritylimidazole–2–ylidene (abbreviated ITr ...


Contraction Analysis Of Functional Competitive Lotka-Volterra Systems: Understanding Competition Between Modified Bacteria And Plasmodium Within Mosquitoes., Nickolas Goncharenko Apr 2020

Contraction Analysis Of Functional Competitive Lotka-Volterra Systems: Understanding Competition Between Modified Bacteria And Plasmodium Within Mosquitoes., Nickolas Goncharenko

Electronic Thesis and Dissertation Repository

We propose and analyze an extension to the classic Competitive Lotka-Volterra (CLV) model. The goal is to model competition between species, with a response from the environment. This response is a function of the population of all species and can represent numerous physical phenomena including resource limitation and immune response of a host due to infection. We name this new system a Functional Competitive Lotka-Volterra (FCLV) model. We mainly use the construction of contraction metrics, to determine global properties of the model. We use this result to analyze the competition between Plasmodium sp. and genetically engineered bacteria within the midgut ...


The Journey Of A Single Polymer Chain To A Nanopore, Navid Afrasiabian Apr 2020

The Journey Of A Single Polymer Chain To A Nanopore, Navid Afrasiabian

Electronic Thesis and Dissertation Repository

Single chain translocation has been eagerly studied for more than two decades due to its importance in biological processes and also, providing a better understanding of polymer dynamics. Polymer translocation can be divided into three stages of reaching the pore, entering the pore and passing through it. We study the delivery of the chain from the bulk to the entrance, which is called the capture process, for a single chain driven by hydrodynamic flow. Our molecular dynamics-lattice Boltzmann simulations show that the converging flow around the nanopore not only facilitates the process of finding the pore but also deforms the ...


Physical Dispersions Of Meteor Showers Through High Precision Optical Observations, Denis Vida Apr 2020

Physical Dispersions Of Meteor Showers Through High Precision Optical Observations, Denis Vida

Electronic Thesis and Dissertation Repository

Meteoroids ejected from comets form meteoroid streams which disperse over time due to gravitational perturbations and non-gravitational forces. When stream meteoroids collide with the Earth's atmosphere, they are visible as meteors emanating from a common point-like area (radiant) in the sky. Measuring the size of meteor shower radiant areas can provide insight into stream formation and age. The tight radiant dispersion of young streams are difficult to determine due to measurement error, but if successfully measured, the dispersion could be used to constrain meteoroid ejection velocities from their parent comets. The estimated ejection velocity is an uncertain, model-dependent value ...


Abelian Integral Method And Its Application, Xianbo Sun Apr 2020

Abelian Integral Method And Its Application, Xianbo Sun

Electronic Thesis and Dissertation Repository

Oscillation is a common natural phenomenon in real world problems. The most efficient mathematical models to describe these cyclic phenomena are based on dynamical systems. Exploring the periodic solutions is an important task in theoretical and practical studies of dynamical systems.

Abelian integral is an integral of a polynomial differential 1-form over the real ovals of a polynomial Hamiltonian, which is a basic tool in complex algebraic geometry. In dynamical system theory, it is generalized to be a continuous function as a tool to study the periodic solutions in planar dynamical systems. The zeros of Abelian integral and their distributions ...


Earthquake Site Characterization Of Rock Sites In Eastern Canada And Stiff Ground Sites In Vancouver, British Columbia, Sameer Ladak Apr 2020

Earthquake Site Characterization Of Rock Sites In Eastern Canada And Stiff Ground Sites In Vancouver, British Columbia, Sameer Ladak

Electronic Thesis and Dissertation Repository

Site characterization is a crucial component in assessing seismic hazard, typically involving in situ shear-wave velocity (VS) depth profiling, and measurement of site amplification including site period. These methods are ideal for soil sites and less reliable in more complex geologic settings including rock sites. A multi-method approach to earthquake site characterization is tested at 25 seismograph stations across Eastern Canada. It is typically assumed these stations are installed on hard rock. We seek to identify which site characterization methods are most suitable at rock sites as well as to confirm the hard rock assumption. Active-source refraction and surface ...


Water Supply Capacity Development In The Context Of Global Change, Patrick Breach Apr 2020

Water Supply Capacity Development In The Context Of Global Change, Patrick Breach

Electronic Thesis and Dissertation Repository

The ANEMI model is an integrated assessment model of global change that emphasizes the role of water resources. The model is based on the principles of system dynamics simulation in order to analyze changes in the Earth system using feedback processes. Securing water resources for the future is a key issue of global change, and ties into global systems of population growth, climate change carbon cycle, hydrologic cycle, economy, energy production, land use and pollution generation.

This thesis focusses on the development of global water supplies necessary to keep pace with a growing population and global economy using an integrated ...


The Influence Of Radiolytically Produced Nitric Acid On The Corrosion Resistance Of Copper-Coated Used Nuclear Fuel Containers, Joseph P. Turnbull Apr 2020

The Influence Of Radiolytically Produced Nitric Acid On The Corrosion Resistance Of Copper-Coated Used Nuclear Fuel Containers, Joseph P. Turnbull

Electronic Thesis and Dissertation Repository

In Canada, the proposed disposal method for high level nuclear waste involves sealing the waste in steel containers with a 3 mm outer copper coating and burying it in a deep geologic repository. However, the thickness of the container is significantly reduced making a reassessment of the influence of γ-radiation, emitted by the waste form, on container corrosion a potential licensing requirement. Under humid aerated conditions, the formation of nitric acid is expected, potentially resulting in the formation of droplets or wetted layers on the container surface. Currently available literature on the corrosion of copper in nitric acid does not ...


Characterization Of Impactite Clay Minerals With Implications For Mars Geologic Context And Mars Sample Return, Christy M. Caudill Apr 2020

Characterization Of Impactite Clay Minerals With Implications For Mars Geologic Context And Mars Sample Return, Christy M. Caudill

Electronic Thesis and Dissertation Repository

Geological processes, including impact cratering, are fundamental throughout rocky bodies in the solar system. Studies of terrestrial impact structures, like the Ries impact structure, Germany, have informed on impact cratering processes – e.g., early hot, hydrous degassing, autometamorphism, and recrystallization/devitrification of impact glass – and products – e.g., impact melt rocks and breccias comprised of clay minerals. Yet, clay minerals of authigenic impact origin remain understudied and their formation processes poorly-understood. This thesis details the characterization of impact-generated clay minerals at Ries, showing that compositionally diverse, abundant Al/Fe/Mg smectite clays formed through these processes in thin melt-bearing breccia ...


Deep Learning On Smart Meter Data: Non-Intrusive Load Monitoring And Stealthy Black-Box Attacks, Junfei Wang Apr 2020

Deep Learning On Smart Meter Data: Non-Intrusive Load Monitoring And Stealthy Black-Box Attacks, Junfei Wang

Electronic Thesis and Dissertation Repository

Climate change and environmental concerns are instigating widespread changes in modern electricity sectors due to energy policy initiatives and advances in sustainable technologies. To raise awareness of sustainable energy usage and capitalize on advanced metering infrastructure (AMI), a novel deep learning non-intrusive load monitoring (NILM) model is proposed to disaggregate smart meter readings and identify the operation of individual appliances. This model can be used by Electric power utility (EPU) companies and third party entities, and then utilized to perform active or passive consumer power demand management. Although machine learning (ML) algorithms are powerful, these remain vulnerable to adversarial attacks ...


Investigating Citation Linkage As A Sentence Similarity Measurement Task Using Deep Learning, Sudipta Singha Roy Mar 2020

Investigating Citation Linkage As A Sentence Similarity Measurement Task Using Deep Learning, Sudipta Singha Roy

Electronic Thesis and Dissertation Repository

Research publications reflect advancements in the corresponding research domain. In these research publications, scientists often use citations to bolster the presented research findings and portray the improvements that come with these findings, at the same time, to make the contents more understandable to the audience by navigating the flow of information. In the science domain, a citation refers to the document from where this information originates but doesn't specify the text span that is actually being cited. A more precise reference would indicate the text being referenced. This thesis develops a framework which can create a linkage between the ...


Source Parameters Of Induced Seismicity In North America, Joanna M. Holmgren Mar 2020

Source Parameters Of Induced Seismicity In North America, Joanna M. Holmgren

Electronic Thesis and Dissertation Repository

Source parameters of earthquakes play a key role in the understanding of earthquake behavior and modelling of seismic hazard. They describe the size of earthquakes, including how much energy is generated during the rupture, and how the ground motion is distributed over different frequency bands and azimuths. The last decade’s increase in induced seismicity caused by oil and gas production has led to an interest in understanding the underlying earthquake processes and how they can be modelled. This thesis is divided into three studies, each examining source parameters of induced earthquakes in North America.

In the first study, I ...


Hierarchical Group And Attribute-Based Access Control: Incorporating Hierarchical Groups And Delegation Into Attribute-Based Access Control, Daniel Servos Mar 2020

Hierarchical Group And Attribute-Based Access Control: Incorporating Hierarchical Groups And Delegation Into Attribute-Based Access Control, Daniel Servos

Electronic Thesis and Dissertation Repository

Attribute-Based Access Control (ABAC) is a promising alternative to traditional models of access control (i.e. Discretionary Access Control (DAC), Mandatory Access Control (MAC) and Role-Based Access control (RBAC)) that has drawn attention in both recent academic literature and industry application. However, formalization of a foundational model of ABAC and large-scale adoption is still in its infancy. The relatively recent popularity of ABAC still leaves a number of problems unexplored. Issues like delegation, administration, auditability, scalability, hierarchical representations, etc. have been largely ignored or left to future work. This thesis seeks to aid in the adoption of ABAC by filling ...


Visualization And Joint Analysis Of Monitored Multivariate Spatio-Temporal Data With Applications To Forest Fire Modelling And Sports Analytics, Devan Becker Mar 2020

Visualization And Joint Analysis Of Monitored Multivariate Spatio-Temporal Data With Applications To Forest Fire Modelling And Sports Analytics, Devan Becker

Electronic Thesis and Dissertation Repository

This thesis develops and applies novel techniques for the study of complex data structures with applications to wildland fire analytics and sports analytics. We consider situations where different models share information, including many different variables recorded simultaneously in aerial wildland fire fighting, how the frequency and severity of wildland fires are related, and how the shot locations of hockey players can be decomposed into spatial components that are shared across different players.

The first study analyzes flight patterns while fighting a wildland fire using several outlier detection techniques. These techniques applied several definitions of ``outlier'' to determine whether or not ...


Driving Maneuver Detection Using Knowledge Distillation Networks, Kyle Windsor Mar 2020

Driving Maneuver Detection Using Knowledge Distillation Networks, Kyle Windsor

Electronic Thesis and Dissertation Repository

In this thesis, we examine the current state of Advanced Driving Assistance Systems (ADAS) and their relation to maneuver prediction in the literature. We then attempt to solve the problem of variable inter-driver behavior by applying a novel distillation learning system using RoadLab data on tracked driver cephalo-ocular gaze behavior in tandem with high-resolution CANbus data. Current training-based methods in maneuver prediction are potentially subject to underfitting as drivers may exhibit different behavior when preparing to maneuver, but it has been shown that drivers can be grouped into at least two distinct behavior models. We use this information to personalize ...


Phage-Bacteria Interaction And Prophage Sequences In Bacterial Genomes, Amjad Khan Feb 2020

Phage-Bacteria Interaction And Prophage Sequences In Bacterial Genomes, Amjad Khan

Electronic Thesis and Dissertation Repository

In this investigation, we examined the interaction of phages and bacteria in bacterial biofilm colonies, the evolution of prophages (viral genetic material inserted into the bacterial genome) and their genetic repertoire. To study the synergistic effects of lytic phages and antibiotics on bacterial biofilm colonies, we have developed a mathematical model of ordinary differential equations (ODEs). We have also presented a mathematical model consisting of a partial differential equation (PDEs), to study evolutionary forces acting on prophages. We fitted the PDE model to three publicly available databases and were able to show that induction is the prominent fate of intact ...


A Micromechanics-Based Multiscale Approach Toward Continental Deformation, With Application To Ductile High-Strain Zones And Quartz Flow Laws, Xi Lu Feb 2020

A Micromechanics-Based Multiscale Approach Toward Continental Deformation, With Application To Ductile High-Strain Zones And Quartz Flow Laws, Xi Lu

Electronic Thesis and Dissertation Repository

Earth’s lithosphere may be regarded as a composite material made of rheologically heterogeneous elements. The presence of these heterogeneous elements causes flow partitioning, making the deformation of Earth’s lithosphere heterogeneous on all observation scales. Understanding the multiscale heterogeneous deformation and the overall rheology of the lithosphere is very important in structural geology and tectonics. The overall rheology of Earth’s lithosphere on a given observation scale must be obtained from the properties of all constituents and may evolve during the deformation due to the fabric development. Both the problem of flow partitioning and characterization of the overall rheology ...


Rare-Metal Alkaline Granite From The Arabian Shield, Saudi Arabia, Abdullah A. Aseri Feb 2020

Rare-Metal Alkaline Granite From The Arabian Shield, Saudi Arabia, Abdullah A. Aseri

Electronic Thesis and Dissertation Repository

Mineral deposits of high field strength elements (HFSE) and rare earth elements (REE) are commonly within granites that have experienced strong post-magmatic alterations. There has been a long debate on whether the mineralization is due to magmatic and/or hydrothermal processes. The Arabian Shield hosts several economical rare-metal alkaline granites that are poorly understood. This work aims to evaluate the nature of the mineralization in three rare-metal granites from the Arabian Shield, showing distinct mineralization styles ranging between disseminated mineralization at Al-Ghurayyah, pegmatite and hematized granite at Jabal Sayid, and quartz veins at Dyaheen.

The granites from all three areas ...


Early Meteoritic Records Of Asteroidal Melt And Impact Environments, Brendt Hyde Feb 2020

Early Meteoritic Records Of Asteroidal Melt And Impact Environments, Brendt Hyde

Electronic Thesis and Dissertation Repository

The characterization of meteorites formed in early melt and impact environments helps deepen our understanding of the processes involved in the formation and modification of terrestrial bodies in the solar system. The main objective of this thesis is to interpret and describe a range of igneous and metamorphic environments on asteroidal bodies, through the chemical, microstructural and isotopic analysis of meteorites, and to place these in the context of evolving rocky bodies in the early protoplanetary disk. Study of the meteorite Northwest Africa (NWA) 869 has led to the novel discovery of a eucrite impactor clast in chondritic regolith material ...


Network Impact Modeling And Analysis: A Qos Perspective, Tarandeep K. Randhawa Feb 2020

Network Impact Modeling And Analysis: A Qos Perspective, Tarandeep K. Randhawa

Electronic Thesis and Dissertation Repository

The International Data Corporation (IDC) estimated that total digital data created, replicated, and consumed was 4.4 Zettabytes (ZB) in the year 2013, 8 ZB in 2015, and predicted to reach 40 ZB by 2020. This massive amount of internet traffic put a great overhead on network capacity which may impact network Quality of Service (QoS) such as latency, jitter, throughput, packet loss, and load balancing. From the Internet Service Provider’s (ISP’s) perspective, understanding the possible impact of the future internet traffic on its network is critical for provisioning their network capacity in a cost-effective manner while meeting ...


Si Nanocrystal Synthesis Via Double Implantation And Variable Implantation, James M. Gaudet Feb 2020

Si Nanocrystal Synthesis Via Double Implantation And Variable Implantation, James M. Gaudet

Electronic Thesis and Dissertation Repository

Silicon (Si) nanocrystals (nc) precipitated from silicon-implanted silicon oxide (SiO2) are of interest as a novel light source for illumination, biomedical applications, optical computing, etc. They have some advantages over conventional III-V compound semiconductor nanocrystals produced by colloidal synthesis. They are compatible with Si/SiO2 based semiconductor processing, are stable, non-toxic at point of synthesis and consumption, and their luminescence falls with the infrared transmission window of biological materials. Unfortunately, synthesis of Si-nc embedded SiO2 is uneconomical and is not as amenable to precise control of the size distribution of nanocrystals as is the case for III-V ...


Analysis Of Oxidatively Damaged Proteins By Mass Spectrometry, Vincent Saullo Feb 2020

Analysis Of Oxidatively Damaged Proteins By Mass Spectrometry, Vincent Saullo

Electronic Thesis and Dissertation Repository

As humans age, exposure to oxidative stress may induce protein degradation or aggregation; both resulting in loss of protein function. Protein oxidative damage remains a dominant pathology in many common ailments. To combat these pathologies, scientists must understand the nature of oxidative modifications and their effects on protein structure and dynamics. This work employs a range of mass spectrometry (MS) methods to characterize and analyze the effects of oxidative damage on the model protein myoglobin (Mb). Mb was oxidized using tert-butyl hydroperoxide, and the resulting modifications were characterized by top-down and bottom-up MS workflows. Hydrogen/deuterium exchange MS indicated elevated ...


Towards The Development Of Network Service Cost Modeling-An Isp Perspective, Yasmeen Ali Feb 2020

Towards The Development Of Network Service Cost Modeling-An Isp Perspective, Yasmeen Ali

Electronic Thesis and Dissertation Repository

Accurate network costing provides insightful information to any ISP for better network planning, profits, and decision making. Developing precise cost models for communication network services has always been a challenge for Internet Service Providers (ISP) due to the complex nature of today’s advanced shared cloud and network infrastructure. Currently, developing and maintaining such cost models require significant effort and time for the network planners in an ISP. The proposed novel methodology reduces the development cycle time significantly for the cost model, which leads to the ISP’s operational cost savings. We also experimented with K-means clustering for grouping router ...


A Visual Analytics System For Making Sense Of Real-Time Twitter Streams, Amir Haghighatimaleki Jan 2020

A Visual Analytics System For Making Sense Of Real-Time Twitter Streams, Amir Haghighatimaleki

Electronic Thesis and Dissertation Repository

Through social media platforms, massive amounts of data are being produced. Twitter, as one such platform, enables users to post “tweets” on an unprecedented scale. Once analyzed by machine learning (ML) techniques and in aggregate, Twitter data can be an invaluable resource for gaining insight. However, when applied to real-time data streams, due to covariate shifts in the data (i.e., changes in the distributions of the inputs of ML algorithms), existing ML approaches result in different types of biases and provide uncertain outputs. This thesis describes a visual analytics system (i.e., a tool that combines data visualization, human-data ...


Studying Resting State And Stimulus Induced Bold Activity Using The Generalized Ising Model And Independent Component Graph Analysis, Sivayini Kandeepan Jan 2020

Studying Resting State And Stimulus Induced Bold Activity Using The Generalized Ising Model And Independent Component Graph Analysis, Sivayini Kandeepan

Electronic Thesis and Dissertation Repository

Although many technical advancements have been made, neuroscientists still struggle to explain the underlying behaviour of how brain regions communicate with each other to form large-scale functional networks. functional Magnetic Resonance Imaging (fMRI) has been commonly used to investigate changes between brain regions over time using the Blood Oxygen Level Dependent (BOLD) signal.

The goal of this thesis is to show the applicability of novel techniques and tools, such as the generalized Ising model (GIM) and the independent component graph analysis (GraphICA), to obtain information on the functional connectivity of populations with altered perception of consciousness. The GIM was used ...


The Effects Of Legacy Sulphur Deposition On Methylmercury Production In Northern Peatlands; Geochemical And Biological Considerations, Jennifer L. Blythe Jan 2020

The Effects Of Legacy Sulphur Deposition On Methylmercury Production In Northern Peatlands; Geochemical And Biological Considerations, Jennifer L. Blythe

Electronic Thesis and Dissertation Repository

Mercury is a ubiquitous element with a complex geochemical cycle. Aquatic ecosystems such as wetland soils convert inorganic mercury to organic, neurotoxic methylmercury though the activity of sulphate-reducing bacteria (SRB). Sulphate stimulates the activity of SRB, and the production of methylmercury in these environments. My aim was to investigate the effect that legacy sulphate has on Hg methylation in northern peatlands through a laboratory sulphate addition experiment with differentially sulphate-exposed peats and a field study of peatlands subjected to different levels of sulphate. Results from the laboratory study indicate that peatlands in regions of higher atmospheric sulphate deposition show enhanced ...


Algorithms For Mappings And Symmetries Of Differential Equations, Zahra Mohammadi Dec 2019

Algorithms For Mappings And Symmetries Of Differential Equations, Zahra Mohammadi

Electronic Thesis and Dissertation Repository

Differential Equations are used to mathematically express the laws of physics and models in biology, finance, and many other fields. Examining the solutions of related differential equation systems helps to gain insights into the phenomena described by the differential equations. However, finding exact solutions of differential equations can be extremely difficult and is often impossible. A common approach to addressing this problem is to analyze solutions of differential equations by using their symmetries. In this thesis, we develop algorithms based on analyzing infinitesimal symmetry features of differential equations to determine the existence of invertible mappings of less tractable systems of ...


Effects Of Impurities On Calcium Oxalate Crystallization As Measured By Atomic Force Microscopy, Himasha Wijesekara Dec 2019

Effects Of Impurities On Calcium Oxalate Crystallization As Measured By Atomic Force Microscopy, Himasha Wijesekara

Electronic Thesis and Dissertation Repository

Calcium oxalate crystals are found in kidney stones as either calcium oxalate monohydrate (COM) or calcium oxalate dihydrate (COD). COM crystals are the most abundant form as they are thermodynamically more stable than COD crystals under physiological conditions. Certain aspartic acid-rich molecules such as osteopontin (OPN) are known to affect stone formation by inhibiting COM and COD growth. We have studied COM {010} and COD {100} faces in the presence of OPN, poly-aspartic acid (poly-ASP) and synthetic peptides derived from OPN to investigate the inhibitor mechanism.

We observed that poly-ASP preferentially inhibits one particular direction of {010} faces on COM ...


Enriched Derivators, James Richardson Dec 2019

Enriched Derivators, James Richardson

Electronic Thesis and Dissertation Repository

In homotopical algebra, the theory of derivators provides a convenient abstract setting for computing with homotopy limits and colimits. In enriched homotopy theory, the analogues of homotopy (co)limits are weighted homotopy (co)limits. In this thesis, we develop a theory of derivators and, more generally, prederivators enriched over a monoidal derivator E. In parallel to the unenriched case, these E-prederivators provide a framework for studying the constructions of enriched homotopy theory, in particular weighted homotopy (co)limits.

As a precursor to E-(pre)derivators, we study E-categories, which are categories enriched over a bicategory Prof(E) associated to E ...


Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol Dec 2019

Numerical And Semi-Analytical Estimation Of Convective Heat Transfer Coefficient For Buildings In An Urban-Like Setting, Anwar Demsis Awol

Electronic Thesis and Dissertation Repository

Urban building arrangements such as packing density, orientation and size are known to influence the microclimate surrounding each building. Studies on the impact of urban microclimatic changes on convective heat transfer coefficient (CHTC) from a stock of buildings, however, have been rare in surveyed literature. The present study focuses on numerical and analytical investigation of CHTC from building-like models with homogeneous set of equal and unequal planar and frontal densities. Consequently, the study discusses the CHTC response in relation to broader changes in the urban surface form. Part of the process involves the development of a simplified one-dimensional semi-analytical CHTC ...