Physical Sciences and Mathematics Commons^™

Ice-Movement History And Kimberlite Indicator Mineral Dispersal Study, Pelly Bay, Lower Boothia Peninsula, And Wager Plateau Areas, Nunavut, Canada, Carl Ozyer

Electronic Thesis and Dissertation Repository

This study reconstructs the ice flow history of the eastern portion of the Keewatin sector of the Laurentide Ice Sheet by integrating field work, remote imagery, and work by others. The study reveals at least seven ice flow phases during the Wisconsinan, including ice streams. A model was developed using inverse distance weighed (IDW) interpolation with GIS to identify and isolate potential kimberlite bedrock sources in kimberlite indicator mineral-rich areas in the Pelly Bay area, Nunavut. Kimberlite indicator mineral (KIM) data were normalized by “peer size” to better understand how KIM grains from three kimberlite sources are distributed within three …

Exploring Bacterial Nanowires: From Properties To Functions And Implications, Kar Man Leung

Electronic Thesis and Dissertation Repository

The discovery of electrically conductive bacterial nanowires from a broad range of microbes provides completely new insights into microbial physiology. Shewanella oneidensis strain MR-1, a dissimilatory metal-reducing bacterium, produces extracellular bacterial nanowires up to tens of micrometers long, with a lateral dimension of ~10 nm. The Shewanella bacterial nanowires are efficient electrical conductors as revealed by scanning probe techniques such as CP-AFM and STM.

Direct electrical transport measurements along Shewanella nanowires reveal a measured nanowire resistivity on the order of 1 Ω∙cm. With electron transport rates up to 10⁹/s at 100 mV, bacterial nanowires can serve as a …

Validation And Application Of Wind Profiler Measurements Of Atmospheric Turbulence, Armin Dehghan

Electronic Thesis and Dissertation Repository

This thesis focuses on the investigation of the reliability of turbulence measurements by radars when the spectral-width method is used. This method employs the spectral widths observed by radar (experimental spectral width) to determine turbulence. However, the experimental width can be affected by non-turbulent effects, including radar geometry. Therefore, the spectral width due to non-turbulent effects (theoretical spectral width) must be removed from the experimental width. This can occasionally lead to negative values of turbulence.

It is our aim (1) to study the effects of both experimental and theoretical spectral widths on the accuracy of turbulence measurements, (2) to study …

Rational Design And Advanced Fabrication Of Metallic Nanostructures For Surface-Enhanced Raman Spectroscopy, Betty Cristina Galarreta

Electronic Thesis and Dissertation Repository

One of the main challenges in analytical science and technology is to develop devices that provide unambiguously the chemical nature of the material of interest with the minimum intrusiveness, the smallest amount of analyte, and the shortest acquisition time. Among the promising methods for such purpose, optical spectroscopy such as surface-enhanced Raman scattering is considered a suitable option. This spectroscopic technique takes advantage of the interaction between an optical field and metallic nanostructures to magnify the electromagnetic field in the vicinity of the nanostructure, resulting in an amplified signal of the vibrational fingerprints of the adsorbed molecules onto the metallic …

Some Single And Combined Operations On Formal Languages: Algebraic Properties And Complexity, Bo Cui

Electronic Thesis and Dissertation Repository

In this thesis, we consider several research questions related to language operations in the following areas of automata and formal language theory: reversibility of operations, generalizations of (comma-free) codes, generalizations of basic operations, language equations, and state complexity.

Motivated by cryptography applications, we investigate several reversibility questions with respect to the parallel insertion and deletion operations. Among the results we obtained, the following result is of particular interest. For languages L₁, L₂ ⊆ Σ^∗, if L₂ satisfies the condition L₂ΣL₂ ∩ Σ⁺L₂Σ⁺ = ∅, then …

Workflow-Net Based Cooperative Multi-Agent Systems, Yehia T. Kotb

Electronic Thesis and Dissertation Repository

Workflow-nets are mathematical frameworks that are used to formally describe, model and implement workflows. First, we propose critical section workflow nets (abbreviated WFCSnet). This framework allows feedbacks in workflow systems while ensuring the soundness of the workflow. Feedback is generally not recommended in workflow systems as they threaten the soundness of the system. The proposed WFCSnet allows safe feedback and limits the maximum number of activities per workflow as required. A theorem for soundness of WFCSnet is presented. Serializability, Separability, Quasi-liveness and CS-Properties of WFCSnet are examined and some theorems and lemmas are proposed to mathematically formalize them. In this …

Microrheology And Microstructure Of Poly(Vinyl Alcohol)-Based Physical Gels, Nan Yang

Electronic Thesis and Dissertation Repository

We study the microrheology and microstructure of physically cross-linked poly(vinyl alcohol) (PVA) gels using atomic force microscopy, dynamic light scattering and particle tracking. We compare the microscopic rheological properties with the bulk properties measured using conventional shear rheometry, and correlate the rheological properties to the structure of the materials.

We develop a new technique for investigating the viscoelastic properties of soft materials using the atomic force microscope. The electronic feedback of an atomic force microscope is modified by adding a small oscillatory voltage to the deflection signal, and the amplitude and phase of the motion of the sample stage is …

Ergodicity And Seismicity Clustering With Applications In Statistical Seismology, Nelson Cho

Electronic Thesis and Dissertation Repository

The implications of understanding fault networks as ergodic systems are addressed here by using the Thirumalai-Mountain metric that identifies effective ergodic periods, when long but finite time intervals are considered. This framework was proven to be useful in statistical seismology studies. Initially, it was established that that the metric can be used to quantify seismicity clustering. Periods of effective ergodicity were characterized by the occurrence of declustered seismicity. This interpretation was implemented for synthetic and seismic data from southern California and Canadian mines.

Next, methods used in the estimation of regional seismic hazard were applied to mining induced seismicity. The …

Noncommutative Complex Geometry Of Quantum Projective Spaces, Ali Moatadelro

Electronic Thesis and Dissertation Repository

In this thesis, we study complex structures of quantum projective
spaces that was initiated in [19] for the quantum projective line,
$\mathbb{C}P^1_q$. In Chapters 2 and 3, which are the main parts of this thesis, we generalize the the results of [19] to the spaces $\mathbb{C}P^{2}_q$ and $\mathbb{C}P^{\ell}_q$. We consider a natural holomorphic structure on the quantum projective space already presented in [11,9],
and define holomorphic structures on its canonical quantum line bundles.
The space of holomorphic sections of these line bundles then will determine
the quantum homogeneous coordinate ring of the quantum projective space as the space of twisted …

Strategies For The Thermal And Photochemical Modification Of Gold Nanoparticles (Aunps) And The Fabrication Of Aunp Hybrid Materials, Hossein Ismaili

Electronic Thesis and Dissertation Repository

Among the existing approaches for the functionalization of the gold nanoparticle (AuNP), a direct interfacial organic reaction of terminal functional groups exposed on the surface of template nanoparticles with various reactants has been shown as a promising strategy to incorporate desired functionality onto the AuNP monolayer. In our own attempts to extend the types of reactions that can be utilized for efficient interfacial modifications of AuNPs, we examined uncatalyzed Huisgen 1,3-dipolar click-type cycloaddition of azide-modified AuNPs to terminal alkynes. These particular reactions were found to be generally too slow to be useful at ambient temperatures but it was shown that …

X-Ray Photoelectron Spectroscopy Studies On The Oxidation Processes Of Nickel, Chromium And Their Alloys, Bradley P. Payne

Electronic Thesis and Dissertation Repository

The reaction of polycrystalline Ni metal surfaces with low pressures (~ 130 Pa) of O₂ gas or H₂O vapour produced thin defective nickel oxide films containing both Ni²⁺ and Ni³⁺ species at 25^oC and 300^oC. Exposure of Ni metal samples to H₂O vapour resulted in a much slower reaction rate when compared to similar doses of O₂ gas. This difference was attributed to a slower place exchange with a surface hydroxyl (OH (ads)) intermediate compared to that of an adsorbed oxygen atom (O (ads)). This OH (ads) species …

Gkm Theory Of Rationally Smooth Group Embeddings, Richard P. Gonzales

Electronic Thesis and Dissertation Repository

This thesis is concerned with the study of rationally smooth group embeddings. We prove that the equivariant cohomology of any of these compactifications
can be described, via GKM-theory, as certain ring of piecewise polynomial functions.
Moreover, building on previous work of Renner, we show that the embeddings under consideration come equipped with both a canonical decomposition into rational cells and a filtration by equivariantly formal closed subvarieties.

The techniques developed in this monograph supply a method for constructing free
module generators on the equivariant cohomology of Q-filtrable GKM-varieties.
Our findings extend the earlier work of Arabia and Guillemin-Kogan on equivariant …

Diagnostic Checking, Time Series And Regression, Esam Mahdi

Electronic Thesis and Dissertation Repository

In this thesis, a new univariate-multivariate portmanteau test is derived. The proposed test statistic can be used for diagnostic checking ARMA, VAR, FGN, GARCH, and TAR time series models as well as for checking randomness of series and goodness-of- fit VAR models with stable Paretian errors. The asymptotic distribution of the test statistic is derived as well as a chi-square approximation. However, the Monte-Carlo test is recommended unless the series is very long. Extensive simulation experiments demonstrate the usefulness of this test and its improved power performance compared to widely used previous multivariate portmanteau diagnostic check. The contributed R package …

Double Helical Hydrogen-Bonded Aaa-Ddd Complexes And Supramolecular Polymers, Hong-Bo Wang

Electronic Thesis and Dissertation Repository

The design and characterization of linear oligomers that self-assemble into double helical structures has been a subject of interest to chemists since the elucidation of the double helix structure of DNA in 1953. Transition metal templates have been widely used in the construction of artificial double helical complexes from linear multidentate ligands. The use of other non-covalent interactions as the driving force in the self-assembly of these types of complexes is less common. Aromatic stacking interactions, anion templates, and salt-bridges have all been applied in this context. The great majority of these investigations have been concerned with the dimerization of …

The Complex Paragenetic History Of Basal Negaunee Iron Formation Iron Ores, Tilden Mine, Marquette District, Upper Michigan, Natalie J. Pietrzak

Electronic Thesis and Dissertation Repository

Variable mineral chemistry and textures of basal Negaunee iron ores mined in the Main Tilden Pit have led to metallurgical difficulties. Core-logging and detailed petrography supported by microprobe investigations, identify three upward fining lithofacies within the Main Pit Carbonate and overlying Martite ore domains: 1) Basal Clastics; 2) Medial BIF; and 3) Granular Iron Formation. Growth fault related subsidence controlled deposition of the Basal Clastics, comprised of detrital quartz dispersed in a matrix of chlorite, cemented by ferri-hydrite, chert and Mg-siderite. Subsequent starvation of any clastic input led to cyclic iron-silica precipitation throughout the deposition of Medial BIF. Increasing wave …

Structure And Strength: Anisotropic Polyvinyl Alcohol Hydrogels And Spider Mite Silk Fibres, Stephen Hudson

Electronic Thesis and Dissertation Repository

Polyvinyl alcohol (PVA) is a hydrophilic, biocompatible polymer which can be made into physically cross-linked hydrogels by freezing and thawing PVA solution. These hydrogels can be made with anisotropic mechanical properties closely matching those of porcine aorta, making them a promising material for producing artificial heart valves and heart valve stents.

Small- and ultra small-angle neutron scattering has been used to study the structure of isotropic and anisotropic PVA hydrogels at length-scales of 2 nm to 10 μm. By supplementing the neutron data with data from atomic force microscopy, a large range of length-scales have been probed, within which structural …

Exploring The Chemistry Of Cyclopentadienyl-Cobalt-Cyclobutadiene (Cpcocb) Complexes And Synthesis Of Side-Chain Cpcocb Polymers, Preeti Chadha

Electronic Thesis and Dissertation Repository

Synthetic metallopolymers have acquired ample attention recently due to their potential applications as precursors to functional soft materials. Organometallic polymers combine the best of both organic and inorganic polymers. Polyferrocenes comprise the major portion of organometallic polymers. Therefore, quest for new monomeric precursors to organometallic polymers has expediated. One efficient method for obtaining main-chain metallopolymers is by the ring opening polymerization (ROP) of strained cyclic metallacylophanes(MCPs). Organometallic polymers containing cyclopentadienyl-cobalt-cyclobutadiene (CpCoCb) have been targeted since early 1990’s due to their isoelectronic nature (cf. ferrocene) with three major groups working in this area. The early CpCoCb containing polymers were prepared …

Models, Techniques, And Metrics For Managing Risk In Software Engineering, Andriy Miranskyy

Electronic Thesis and Dissertation Repository

The field of Software Engineering (SE) is the study of systematic and quantifiable approaches to software development, operation, and maintenance. This thesis presents a set of scalable and easily implemented techniques for quantifying and mitigating risks associated with the SE process. The thesis comprises six papers corresponding to SE knowledge areas such as software requirements, testing, and management. The techniques for risk management are drawn from stochastic modeling and operational research.

The first two papers relate to software testing and maintenance. The first paper describes and validates novel iterative-unfolding technique for filtering a set of execution traces relevant to a …

Numerical Simulations Of Composition Changes In The High Latitude Thermosphere During Disturbed Conditions, Albert T. Russell

Electronic Thesis and Dissertation Repository

The closure of magnetospheric currents in the high latitude ionosphere makes the
high latitude thermosphere a very dynamic environment. The composition and dynamics
of this region become even more complex during geomagnetic disturbances
as the electric fields from the magnetosphere now have the ability to substantially
alter the winds and composition of this region. This complexity is especially apparent
in mass spectrometer observations of composition changes, with heavier gases
(N₂,O₂, andAr) showing substantial enhancements while lighter gases (He and O)
normally exhibit moderate to severe depletions. Quantifying the changes in atomic
and molecular oxygen can be …

Magnetic Diffusion In Star Formation: From Clouds To Cores To Stars To Disks, Wolfgang B. Dapp

Electronic Thesis and Dissertation Repository

We investigate magnetic diffusion on scales from molecular clouds over prestellar and
protostellar cores down to young stellar objects (YSOs) and their surrounding protoplanetary disk.
In Chapter 2, we present thin-sheet simulations that exhibit long-lived magnetic-tension-driven oscillations, founded in the interaction of the cloud's magnetic field with that anchored in an external medium. In contrast with "local" simulations in a periodic box, where turbulence decays away in approximately a sound crossing time, and needs to be continually replenished by driving, our simulation has "global" aspects, and retains some kinetic energy indefinitely. We provide an analytical explanation for these modes, that …

The Effect Of The Environment On The Corrosion Products And Corrosion Rates On Gas Transmission Pipelines, Brent Sherar

Electronic Thesis and Dissertation Repository

This thesis reports a series of investigations examining external corrosion processes along gas transmission pipelines. TransCanada PipeLines Ltd. (TCPL) has developed six proposed corrosion scenarios to describe external pipeline corrosion, based primarily on corrosion products and corrosion rates (CRs) observed at field sites. The six proposed corrosion scenarios can be divided into two groups: abiotic and biotic. The three abiotic corrosion scenarios are (1) anaerobic corrosion, (2) aerobic corrosion, and (3) anaerobic corrosion turning aerobic; while (4) anaerobic corrosion with microbial effects, (5) aerobic corrosion turning anaerobic with microbial effects, and (6) anaerobic corrosion with microbial effects turning aerobic comprise …

Arrangements Of Submanifolds And The Tangent Bundle Complement, Priyavrat Deshpande

Electronic Thesis and Dissertation Repository

Drawing parallels with the theory of hyperplane arrangements, we develop the theory of arrangements of submanifolds. Given a smooth, finite dimensional, real manifold $X$ we consider a finite collection $\A$ of locally flat codimension $1$ submanifolds that intersect like hyperplanes. To such an arrangement we associate two posets: the \emph{poset of faces} (or strata) $\FA$ and the \emph{poset of intersections} $L(\A)$. We also associate two topological spaces to $\A$. First, the complement of the union of submanifolds in $X$ which we call the \emph{set of chambers} and denote by $\Ch$. Second, the complement of union of tangent bundles of these …

Coupled Heat And Water Transport In Frozen Soils, Ranjeet M. Nagare

Electronic Thesis and Dissertation Repository

The effect of freezing on soil temperature and water redistribution was examined in four Mesocosms maintained at different initial water content profiles. An innovative experimental setup involving use of a frozen base layer acting as a proxy to permafrost beneath an active layer made up of packed and undisturbed peat cores was used. The experimental setup was successfully validated for its ability to maintain one dimensional change in temperature and soil water content in frozen soil. There was a substantial amount of water redistribution towards the freezing front, enough to create an impermeable frozen, saturated zone within 15 cm of …

Uncertainty Estimation Of Extreme Precipitations Under Climate Change: A Non-Parametric Approach, Tarana A. Solaiman

Electronic Thesis and Dissertation Repository

Assessment of climate change impacts on hydrology at watershed scale incorporates (a) downscaling of global scale climatic variables into local scale hydrologic variables and (b) assessment of future hydrologic extremes. Atmosphere-Ocean Global Climate Models (AOGCM) are designed to simulate time series of future climate responses accounting for human induced green house gas emissions. The present study addresses the following limitations of climate change impact research: (i) limited availability of observed historical information; (ii) limited research on the detection of changes in hydrologic extremes; and (iii) coarse spatio-temporal resolution of AOGCMs for use at regional or local scale. Downscaled output from …

Design And Syntheses Of Fluorescent Cytosine Analogues, David W. Dodd

Electronic Thesis and Dissertation Repository

The avid hybridization of peptide nucleic acid (PNA) to DNA and RNA along with the molecule’s biological stability has led it to be used in both antisense and antigene capacities. PNA acts against translation via a steric blockade mechanism. It is therefore reasonable to assume that increased heteroduplex stability could lead to increased potency. Two ways of doing this were explored. I) N-Terminal attachment of a platinous chloride chelating moiety to PNA complementary to Xenopus noggin was synthesized with the objective of selective, covalent platination of the target transcript in vivo. Phenotypes consistent with knockdown of the selected …

Characteristic Polynomial Of Arrangements And Multiarrangements, Mehdi Garrousian

Electronic Thesis and Dissertation Repository

This thesis is on algebraic and algebraic geometry aspects of complex hyperplane arrangements and multiarrangements. We start by examining the basic properties of the logarithmic modules of all orders such as their freeness, the cdga structure, the local properties and close the first chapter with a multiarrangement version of a theorem due to M. Mustata and H. Schenck.

In the next chapter, we obtain long exact sequences of the logarithmic modules of an arrangement and its deletion-restriction under the tame conditions. We observe how the tame conditions transfer between an arrangement and its deletion-restriction.

In chapter 3, we use some …

An Analytical And Numerical Treatment Of Inclined Elliptical Orbits About A Kerr Black Hole, Peter G. Komorowski

Electronic Thesis and Dissertation Repository

Since its publication in 1915, Einstein's theory of general relativity has yielded significant results; they include: analytical solutions to the Einstein field equations; improved analysis of orbital dynamics; and the prediction of gravitational wave (GW) radiation. Gravitation is the weakest of the fundamental interactions; and theoretical models of GW generation and propagation show that its detection poses a significant technical challenge. Unlike the study of electromagnetic radiation, experiments within the laboratory are virtually impossible; so astronomical sources of GW, such as binary black hole systems, offer an alternative. But GW detection remains difficult. The matched filtering techniques used to discriminate …

Late Pleistocene Climate And Proboscidean Paleoecology In North America: Insights From Stable Isotope Compositions Of Skeletal Remains, Jessica Z. Metcalfe

Electronic Thesis and Dissertation Repository

This thesis uses the carbon, nitrogen, and oxygen isotope compositions of mammoth (Mammuthus) and mastodon (Mammut) skeletal remains to reconstruct paleoclimate and paleoecology in Late Pleistocene North America. Analytical methods, sampling strategies, environmental adaptations and seasonal behaviors of proboscideans were investigated.

Reliable and reproducible results are crucial for a study of this nature. A persistent methodological problem in the isotope analysis of structural carbonate in bioapatite was solved by reacting bioapatite under “sealed vessel” conditions.

Growth rate determinations are critical for designing sampling strategies and interpreting results. Histological and isotopic measurements demonstrated variations in enamel growth …

Strategies For Waveform Tomography Of Long-Offset, 2-D Exploration Seismic Data, Andrew J. Brenders

Electronic Thesis and Dissertation Repository

Waveform Tomography, combines starting models from traveltime tomography with tomographic waveform inversion. This approach to inversion recovers a “best fit” velocity model by iteratively minimizing the misfit between the observed, frequency-domain waveform data and modelled, synthetic waveforms. The method is both computationally efficient and an improvement over ray-based tomographic methods. Synthetic benchmark studies and experiments with long-offset, 2-D, exploration seismic field data, demonstrate that Waveform Tomography can yield accurate, high resolution velocity models, vital in seismic exploration for hydrocarbons.

I first present an application of Waveform Tomography to long-offset, 2-D, synthetic marine seismic data using the 2004 BP velocity benchmark. …

Impact Of Geomagnetically Induced Currents On Power Transformers, Jonathan E. Berge

Electronic Thesis and Dissertation Repository

This thesis deals with the impact of Geomagnetically Induced Current (GIC) on power transformers in electrical power systems. A simulator to calculate the flows of GIC in an electrical power network, based on an assumed or measured induced geoelectric potential is proposed. This simulator includes all needed mapping techniques to handle a system that cover a large geographical area.

A correlation between GIC and the reactive power absorbed in the core of the saturated transformer is proposed. That correlation is used to estimate GIC in a transformer utilizing existing reactive power measuring infrastructure within the electrical grid without the need …