Physical Sciences and Mathematics Commons^™

An Optimal Threshold Strategy In The Two-Envelope Problem With Partial Information, Martin Egozcue, Luis Fuentes García

Martin Egozcue

No abstract provided.

Alignment Of The Western And Eastern Passage Tombs At Knowth Tomb 1, Frank Prendergast, Tom Ray

Book/Book Chapter

This report presents a summary account of two surveys undertaken by the authors to determine and interpret the alignments of the western and eastern passage tombs at Knowth, Co. Meath. The findings indicate that contrary to earlier suggestions, the eastern passage and the western passage (inner and outer) are not aligned towards sunrise and sunset respectively at the period of the vernal and autumnal equinoxes.

One-Dimensional Weakly Nonlinear Model Equations For Rossby Waves, David Henry, Rossen Ivanov

Articles

In this study we explore several possibilities for modelling weakly nonlinear Rossby waves in fluid of constant depth, which propagate predominantly in one direction. The model equations obtained include the BBM equation, as well as the integrable KdV and Degasperis-Procesi equations.

Study Of Nonlinear Vibration Of Euler-Bernoulli Beams By Using Analytical Approximate Techniques, Saman Bagheri, Ali Nikkar

Ali Nikkar

In this paper, nonlinear responses of a clamped-clamped buckled beam are investigated. Two efficient and easy mathematical techniques called He’s Variational Approach and Laplace Iteration Method are used to solve the governing differential equation of motion. To assess the accuracy of solutions, we compare the results with the Runge-Kutta 4th order. The results show that both methods can be easily extended to other nonlinear oscillations and it can be predicted that both methods can be found widely applicable in engineering and physics.

Ligand-Receptor Interactions For Supramolecular Disassembly With Applications In Screening And Drug Delivery, Diego F. Amado Torres

Diego Amado Torres

Proteins have the capacity to bind specific sets of compounds known as ligands, these are small molecules with a recurrent theme in their molecular design that is a characteristic exploited here to (i) identify particular affinities of small molecules for proteins with the aim of using them as ligands, inhibitors, or targeting moieties in more complex systems by means of a methodology that screens small molecules based on protein affinity; (ii) decorate a self-assembling supramolecular system at different positions, making it responsive to a complementary protein with the aim of exploring differences in disassembly and sensitivity of the release of ...

Initial Characterization Of A Conserved Active Site Residue For The Cdc34 Ubiquitin Conjugating Enzyme, Arvin Akoopie

Theses

Ubiquitin-conjugating enzymes (E2s) covalently modify protein substrates with ubiquitins. The active site cysteine residues on E2s are essential for catalyzing the transfer of ubiquitin from the E2 active site onto the protein substrate, however there is a limited amount of information available concerning additional active site residues for E2s that may also participate in catalysis. Cdc34 is an essential E2 that has merited the lion’s share of attention for biochemical analysis of the E2 family. Previous phylogenetic analysis of Cdc34 amino acid sequences has identified an invariably conserved histidine residue close to the active site cysteine in the primary ...

Tweet Mapper Visualization Software, Andrew W. Nash, Shawn M. Cox, Michael T. Adams

University of Tennessee Honors Thesis Projects

No abstract provided.

Predicting Response In Mobile Advertising With Hierarchical Importance-Aware Factorization Machine, Richard Jayadi Oentaryo, Ee Peng Lim, David Jia Wei Low, David Lo, Michael Finegold

Research Collection School Of Information Systems

Mobile advertising has recently seen dramatic growth, fueled by the global proliferation of mobile phones and devices. The task of predicting ad response is thus crucial for maximizing business revenue. However, ad response data change dynamically over time, and are subject to cold-start situations in which limited history hinders reliable prediction. There is also a need for a robust regression estimation for high prediction accuracy, and good ranking to distinguish the impacts of different ads. To this end, we develop a Hierarchical Importance-aware Factorization Machine (HIFM), which provides an effective generic latent factor framework that incorporates importance weights and hierarchical ...

Capturing And Analyzing Network Traffic From Common Mobile Devices For Security And Privacy, Billy Overton

Undergraduate Honors Theses

Mobile devices such as tablets and smartphones are becoming more common, and they are holding more information. This includes private information such as contacts, financial data, and passwords. At the same time these devices have network capability with access to the Internet being a prime feature. Little research has been done in observing the network traffic produced by these mobile devices. To determine if private information was being transmitted without user knowledge, the mobile capture lab and a set of procedures have been created to observe, capture and analyze the network traffic produced by mobile devices. The effectiveness of the ...

Boundaries Of A Complex World, Andrei Ludu

Andrei Ludu

No abstract provided.

Electronic & Magnetic Properties Of Ba(Fe,Co)2as2 & Uru2si2, Travis J. Williams

Open Access Dissertations and Theses

This thesis details a collection of experiments performed on two condensed matter systems, Co-doped BaFe₂As₂ and URu₂Si₂. These two materials are related by their structural type (ThCr₂Si₂-type) serving as great examples of the diversity of material properties present in this family. They are also both superconducting materials and belong to the collection of strongly-correlated electron systems. The interest in studying the Ba(Fe,Co)₂As₂ group of materials is due to the high superconducting transition temperature in these (and related) materials, while the compound URu₂Si_{2 ...}

Phase Field Crystal Studies Of Strain-Mediated Effects In The Thermodynamics And Kinetics Of Interfaces, Jonathan F E Stolle

Open Access Dissertations and Theses

In this dissertation, the Phase Field Crystal (PFC) Method is used to study a number of problems in which interfaces and elastic effects play important roles in alloys. In particular, the three topics covered in this work are grain boundary thermodynamics in alloys, dislocation-mediated formation of clusters in binary and ternary alloys, and solutal effects in explosive crystallization. Physical phenomena associated with grain boundaries, such as Read-Shockley-like behaviour and Gibbs adsorp- tion theorem, were shown to be accurately captured in both PFC- and XPFC-type models. In fact, a connection between the solute segregation behaviour and physical properties of the system ...

Neutron Scattering Studies Of Magnetic Oxides Based On Triangular Motifs, Katharina Fritsch

Open Access Dissertations and Theses

The following dissertation presents neutron scattering studies on three specific magnetic insulating oxide materials whose lattice is based on triangular structural motifs. Each of the three materials studied, LuCoGaO₄, Co₃V₂O₈ and Tb₂Ti₂O₇, displays an interesting disordered ground state that is reached by different mechanisms: site disorder, geometric frustration, and quantum fluctuations induced by a transverse magnetic field. The main focus of this work is the characterization of the resulting magnetic ground states and magnetic excitations within these systems.

Chapters 3, 4 and 5 contain original work in the form ...

Direct Numerical Simulations Of Magnetic Helicity Conserving Astrophysical Dynamos, Alex J. Cridland

Open Access Dissertations and Theses

Here we present direct numerical simulations of a shearing box which models the MHD turbulence in astrophysical systems with cylindrical geometries. The purpose of these simulations is to detect the source of the electromotive force - the driver of large scale magnetic field evolution. This electromotive force is responsible for the large scale dynamo action which builds and maintains the magnetic field against dissipation in plasmas. We compare the estimates of the electromotive force from the kinematic approximation of mean field theory - the most prevalent theory for astrophysical dynamos - with a modified version of mean field theory which restricts the electromotive ...

Asymptotic Theory For Three Infinite Dimensional Diffusion Processes, Youzhou Zhou

Open Access Dissertations and Theses

This thesis is centered around three infinite dimensional diffusion processes:

(i). the infinitely-many-neutral-alleles diffusion model [Ethier and Kurtz, 1981],

(ii). the two-parameter infinite dimensional diffusion model [Petrov, 2009] and [Feng and Sun, 2010],

(iii). the infinitely-many-alleles diffusion with symmetric dominance [Ethier and Kurtz, 1998].

The partition structures, the ergodic inequalities and the asymptotic theory of these three models are discussed. In particular, the asymptotic theory turns out to be the major contribution of this thesis.

In Chapter 2, a slightly altered version of Kingman's one-to-one correspondence theorem on partition structures is provided, which in turn becomes a handy tool ...

Likelihood-Based Inferential Methods For Some Flexible Cure Rate Models, Suvra Pal

Open Access Dissertations and Theses

Recently, the Conway-Maxwell Poisson (COM-Poisson) cure rate model has been proposed which includes as special cases some of the well-known cure rate models discussed in the literature. Data obtained from cancer clinical trials are often right censored and the expectation maximization (EM) algorithm can be efficiently used for the determination of the maximum likelihood estimates (MLEs) of the model parameters based on right censored data.

By assuming the lifetime distribution to be exponential, lognormal, Weibull, and gamma, the necessary steps of the EM algorithm are developed for the COM-Poisson cure rate model and some of its special cases. The inferential ...

Application Of Magnetic “Fishing” And Mass Spectrometry For Function-Based Assays Of Biomolecular Interactions, Meghan J. Mcfadden

Open Access Dissertations and Theses

The human interactome presents a goldmine of potentially powerful therapeutic targets, yet very few small molecule modulators of protein-protein interactions (PPI) have been identified. PPI pose a particular challenge for drug discovery, and one of the major obstacles to fully exploiting these interactions is a lack of appropriate technologies to screen for modulating compounds. This thesis aims to address the need for function- based approaches that target PPI by using magnetic beads (MB) and mass spectrometry (MS) to develop efficient assays to monitor these interactions and their modulation by small molecules. The work begins with the validation of a novel ...

Effects Of Thinning On Carbon Dynamics In A Temperate Coniferous Forest, Janelle S. Trant

Open Access Dissertations and Theses

Forest ecosystems are a significant component of the global carbon (C) cycle. Afforestation is considered a cost-effective and ecologically viable means to sequester atmospheric carbon. However, afforestation requires intensive management practices, including thinning, to maintain and enhance the carbon sequestration capability of the forest. This study examines thinning effects on forest carbon dynamics using eddy covariance (EC) methods. In January 2012, a 74-year-old white pine (Pinus strobus) plantation located in southern Ontario was selectively thinned. Approximately 30% of trees, equating to 2308 m³ of wood (sawlogs and pulpwood), were removed to improve light, water and nutrient availability for remaining ...

Defect Localization Using Dynamic Call Tree Mining And Matching And Request Replication: An Alternative To Qos-Aware Service Selection, Anis Yousefi

Open Access Dissertations and Theses

This thesis is concerned with two separate subjects; (i) Defect localization using tree mining and tree matching, and (ii) Quality-of-service-aware service selection; it is divided into these parts accordingly.

In the first part of this thesis we present a novel technique for defect localization which is able to localize call-graph-affecting defects using tree mining and tree matching techniques. In this approach, given a set of successful executions and a failing execution and by following a series of analyses we generate an extended report of suspicious method calls. The proposed defect localization technique is implemented as a prototype and evaluated using ...

Development Of A Thgem Imaging Detector With Delay Line Readout, Andrei Hanu

Open Access Dissertations and Theses

Position sensitive detectors represent a class of particle detectors widely used in high-energy physics, astrophysics, biophysics and medicine for imaging the spatial distribution of various radioactive sources. In recent years, a new class of gas based detectors, so-called micropattern gas detectors (MPGDs), has emerged. While modern MPGDs rival solid state detectors in terms of spatial and temporal resolution, their cost of production is significantly lower. A Thick Gaseous Electron Multiplier (THGEM) imaging detector, with a two-dimensional delay line readout, has been constructed as a concept for a large area imaging detector with reasonable spatial resolution. The delay line based THGEM ...

The Wet Adhesion Of Polyvinylamine To Cellulose, John-Louis Diflavio

Open Access Dissertations and Theses

A systematic investigation of Polyvinylamine (PVAm) as a strength-enhancing polymer for wet paper was undertaken through the development of a new test method that simulates the influence of polymers on fibre-fibre bonding in paper. Pairs of wet regenerated cellulose membranes were laminated using the paper strength-enhancing polymer as the lamination adhesive. The resulting laminates served as a physical model for fibre-fibre bonds in paper and the wet laminate strength was determined by ninety degree peeling experiments. Key experimental parameters and sources of error were identified.

The mechanism of PVAm paper wet strength enhancement was explored by the wet cellulose delamination ...

Direct Infusion Lipidomics: Profiling The Lipidome Of A Composite Tailings Reclamation Site, Paul A. Hodgson

Open Access Dissertations and Theses

The comprehensive analysis of intact lipids (called lipidomics) can provide information about the presence of microbial communities in an ecosystem and assist in understanding the biogeochemistry in that system. In previous work we had developed a method to determine the profiles of eight phospholipid classes in a soil microorganism by direct-infusion electrospray mass spectroscopy using tandem mass spectrometry. The work done in this study encompasses first the optimization of previous methodology for use with water and sediment samples containing low concentration of phospholipids and large amounts of organic contaminants and secondly the application of this method to the analysis of ...

Multinuclear Nmr Spectroscopy Methods For The Study Of Structure And Dynamics In Solid-State Electrolytes For Lithium Ion Batteries, Tara L. Spencer Noakes

Open Access Dissertations and Theses

This thesis evaluates several solid-state NMR spectroscopy approaches to studying lithium ion dynamics in solid-state electrolytes. With the goal of reducing the risks associated with current liquid electrolytes, solid-state electrolytes provide non-flammable materials that are also stable against attack by cathode and anode materials. Solid-state NMR spectroscopy offers a versatile method to determine structural details and can also provide information about ion mobility in solid-state electrolytes. Challenges involved in the study of solid-state electrolytes include the difficulty in distinguishing between ^6,7Li resonances due to the small chemical shift range of diamagnetic lithium species. The NMR methods selected in ...

Nutrition, Childhood Development And Prevalence Of Anemia In Ghanaian Children: Analysis Of Health Survey, Joycelyne E. Ewusie

Open Access Dissertations and Theses

Malnutrition and Anemia in children continue to be major public health challenges in most developing countries, particularly in Africa. Malnutrition and Anemia pervade all aspects of their health, growth, cognitive and social development. They lead to irreversible and lifelong effects that prevent children from realising their full potential. This study was designed to examine the prevalence and determinants of malnutrition and anemia in children under 5 years of age in the Ghanaian population. This research is based on data from the Ghana Demographic and Health Survey (GDHS) 2008, obtained from the Ghana Statistical Service (GSS). The survey is an extensive ...

Biometric-Based Carbon Estimates And Environmental Controls Within An Age-Sequence Of Temperate Forests, Michelle V. Kula

Open Access Dissertations and Theses

Understanding the response of forest carbon uptake and growth to interannual climate variability and forest management practices is important, given the large quantity of carbon stored in forests, and their significant role in the global carbon cycle. Since 2004, biometric and micrometeorological measurements were taken in an age-sequence (10-, 38- and 73-years-old as of 2012) of white pine (Pinus strobes L.) plantation forests in southern Ontario, Canada, providing an 8 year record of carbon sequestration, growth and climate. The 73-year old conifer site was thinned in early 2012, where 25% of trees were removed to improve light and water dynamics ...

In Vivo X-Ray Fluorescence Of Bone Lead In The Study Of Human Lead Metabolism In A Cohort Of The General Population And Smelter Employees, Sepideh Behinaein

Open Access Dissertations and Theses

After developing the clover-leaf geometry system, the system was used for the first time in a major survey in 2008 to measure the lead levels of 497 smelter employees in the province of New Brunswick in Canada, who participated in a lead study during the time interval of 14 January to 6 March 2008. Participants were measured for lead concentration in the left tibia and right calcaneus, each for 30 min. The minimum detection limit (MDL) of the clover leaf geometry detector system was improved by a factor 3.1 compared to a conventional system. Improvement of the detection system ...

What You See Is What You Get: Synthetic Photometry Of Hydrodynamic Simulations Of Binary Star Systems, Kevin A. Sooley

Open Access Dissertations and Theses

In this thesis we present a procedure by which synthetic photometry of a hydrodynamic model of star or star-like object can be calculated in a regime where the photosphere is not radially resolved. In order to properly model the unresolved photosphere, we present a method where pressure and density are integrated outward from the outermost resolved radius of the star and then interpolated in temperature-surface gravity space between a set of MARCS \citep{Gustafsson2008a} stellar atmosphere models. These interpolations are accurate to within 10\% of expected temperature values and are determined by minimizing the difference between the integrated pressure, density ...

On The Number Of Distinct Squares In Strings, Mei Jiang

Open Access Dissertations and Theses

We investigate the problem of the maximum number of distinct primitively rooted squares in a string. In comparison to considering general strings, the number of distinct symbols in the string is introduced as an additional parameter of the problem. Let S(d,n) = max {s(x) | x is a (d,n)-string}, where s(x) denotes the number of distinct primitively rooted squares in a string x and a (d,n)-string denotes a string of length n with exactly d distinct symbols.

Inspired by the d-step approach which was instrumental in Santos' tackling of the Hirsch conjecture, we introduce ...

An Analysis Of The Practical Dpg Method, Jay Gopalakrishnan, Weifeng Qiu

Mathematics and Statistics Faculty Publications and Presentations

We give a complete error analysis of the Discontinuous Petrov Galerkin (DPG) method, accounting for all the approximations made in its practical implementation. Specifically, we consider the DPG method that uses a trial space consisting of polynomials of degree p on each mesh element. Earlier works showed that there is a "trial-to-test" operator T, which when applied to the trial space, defines a test space that guarantees stability. In DPG formulations, this operator T is local: it can be applied element-by-element. However, an infinite dimensional problem on each mesh element needed to be solved to apply T. In practical computations ...

Mechanistic Aspects Of The Complexation, Chalcogen Abstraction And Sigma Bond Insertion Reactions By Transient Silylenes And Germylenes In Solution, Svetlana S. Kostina

Open Access Dissertations and Theses

The complexation reactions of silylenes (SiMe₂, SiPh₂ and SiMes₂) and germylenes (GeMe₂, GePh₂ and GeMes₂) with a series of O-, S-, N- and P-donors have been studied in hexanes solution. The equilibrium constants for complexation of SiMes₂ and GeMes₂ with 7 Lewis bases were determined, and demonstrate that the silylene is more Lewis acidic than the germylene by ca. 1 kcal mol^-1. Diethyl ether reacted with the six tetrellylenes with equilibrium constants that decrease in the order SiPh₂ > SiMe₂ > GePh₂ > GeMe₂ > SiMes₂ > GeMes₂, establishing a ...