Physical Sciences and Mathematics Commons^™

Optimal Control Applied To Population And Disease Models, Rachael Lynn Miller Neilan

Doctoral Dissertations

This dissertation considers the use of optimal control theory in population models for the purpose of characterizing strategies of control which minimize an invasive or infected population with the least cost. Three different models and optimal control problems are presented. Each model describes population dynamics via a system of differential equations and includes the effects of one or more control methods.

The first model is a system of two ordinary differential equations describing dynamics between a native population and an invasive population. Population growth terms are functions of the control, constructed so that the value of the control may affect …

High-Sensitivity Spectral Fluorescence Lifetime Imaging For Resolving Spectroscopically Overlapping Species, Justin Lee Crawford

Masters Theses

The capability to resolve the contributions from spectroscopically overlapping fluorophores has enabled significant breakthroughs in cellular imaging. However, commercial microscopes for this purpose use analog light detection with least squares curve-fitting analysis and improvements in sensitivity are needed. To this end, a microscope has been constructed with high throughput and single-photon detection capability. The fluorescence is separated through use of a prism spectrometer or a series of dichroic mirrors into four spectral bands and detected using four single-photon avalanche diode (SPAD) detectors, which provide high-quantum efficiency in the red spectral region. The detectors are connected to a time-correlated single photon …

Fluorescence Characterization Of Karst Aquifers In East Tennessee, Teresa L. Brown

Masters Theses

Karst and fractured rock aquifers are primary sources of drinking water in the Appalachian region, even though most are inherently susceptible to surface-derived contamination. Many of the obstacles to water supply protection in such systems could be alleviated through the use of tracer testing to delineate recharge areas and surface-to-groundwater connections. Tracer testing is currently under-utilized, however, due to public safety concerns and ambivalence on the part of regulatory agencies. This study aimed to address this issue through a characterization of the fluorescent properties of typical carbonate aquifers for the purpose of refining the timing and design of low-concentration dye …

Microfluidic Device For The Electrokinetic Manipulation Of Single Molecules, Jason Keith King

Masters Theses

Manipulation and trapping of single molecules in solution is a useful tool for studies of biological molecules and molecular dynamics, but has to date been implemented in only one or two dimensions. The goal of the research in this thesis is to develop a microfluidic device to address the need for three-dimensional manipulation of single fluorescent molecules in solution. The device consists of two pairs of platinum electrodes deposited onto two standard borosilicate glass coverslips via ultraviolet microlithography and ionic sputtering. The two coverslips are sandwiched together such that the electrode tips form a tetrahedral configuration, and by applying appropriate, …

Some Congruence Modulo 2 Statements Of Primitive Conway Vassiliev Invariants., James M. Dawson

Masters Theses

Polynomial knot invariants can often be used to define Vassiliev invariants on singu- lar knots. Here Vassiliev invariants form the Conway, Jones, HOMFLY, and Kauffman polynomials are explored. Also, some explanation is given about how symbols of the Jones and Conway polynomial can evaluated on suitable chord diagrams. These in- variants are further used to find expressions that are congruent modulo 2 to some low degree invariants derived from the Primitive Conway polynomial.

Factors Affecting Redox Magnetohydrodynamics For Flow In Small Volumes, Matthew D. Gerner

Graduate Theses and Dissertations

Lab-on-a-chip technologies offer the possibility of developing analytical devices that are low-cost, portable, disposable, fast, and operable by non-technical personnel. Such devices require automated methods to manipulate ultra-small volumes (picoliters) of samples and solution, including pumping, stirring, and positioning. Current methods for ultra-small volume microfluidics have limitations that restrict their use including high voltage requirements, disadvantageous flow profiles or rates, and relatively complicated fabrication due to mechanical parts. Redox magnetohydrodyanmics (RMHD) that utilizes permanent magnets for portability shows promise as a micropump with ease of switching flow direction, no moving parts, compatibility with both aqueous and non-aqueous solutions, low voltages …

Grades 7-8 Mean, Median, And Mode, Rich Miller Iii

Math

This lesson is a math lesson for seventh and eighth grade students on mean, medium, and mode. Through this lesson students will be able to understand the measures of central tendency and their definitions, how to calculate them and what steps are involved, and how the theories can be applied on real life. In this lesson, students are tiered by ability and are able to pick a project based off of their interest and the math concept they are working on. Each activity has a tiered task card to guide the students.

An Automated Approach To The Study And Classification Of Colliding And Interacting Galaxies, Steven Alvaro Boada

Masters Theses

Colliding galaxies are perhaps the greatest events changing and evolving our Universe. Consequently, the need for an understanding of how that interaction originated is very important. This thesis presents a framework in which the study of these events can be conducted in a timely and efficient manner. A genetic algorithm coupled with an initial conditions generator, a physics engine and an analysis package performs an automated search to visually match an unknown galactic interaction with a known event, thus providing the starting conditions that created such an interaction.

Single Molecule Detection Of Near-Infrared Phthalocyanine Dyes, You Li

Masters Theses

The major advantage associated with near-infrared monitoring is the fact that few compounds show intrinsic fluorescence in this region of the spectrum and hence background from other molecules is reduced. Phthalocyanine dyes provide emission at deep red and near infrared wavelengths but have excellent photostability and hence are an attractive candidate for near-infrared fluorescence bioassay applications. However, because of their small Stokes shifts, non-standard methods are needed for optimum separation of fluorescence from scattered laser light. This thesis reports the development of a custom confocal microscope that uses a lowcost laser diode operating at 667 nm for sample excitation and …

Geometrical Effects On Electromagnetic Enhancement To Sers From Metal Nanoparticle Dimer Arrays, Abigail Laurel Gaddis

Masters Theses

Much recent effort has been devoted to the study of the optical properties of metal nanoparticle substrates. In such finely ordered structures, surface plasmons can be induced by incident light. These collective excitations of the electrons in the nanoparticle create localized areas of high electromagnetic field intensity. The intense local fields generated are of interest for various applications, including Surface-enhanced Raman Scattering (SERS) for molecular detection and sensing. In this thesis, the optical properties of various nanoparticle dimer and array geometries are considered, including gold triangular prism dimers and silver spherical dimers. The effect of SERS due to electromagnetic interaction …

Elemental Analysis Of Soils Using Laser-Induced Breakdown Spectroscopy (Libs), Ningfang Yang

Masters Theses

Laser-induced breakdown spectroscopy (LIBS) has been applied for the quantitative analysis of various samples, but it is controversial for chemically-complex soils. In order to study the effect of delay time, gate width, and repetition rate on the LIBS signal in soil, the emission line at 396.84 nanometer was selected. The results indicated that repetition rate, delay time, and gate width significantly affected the LIBS signal, delay time was more important than gate width in controlling the LIBS signal. The optimum instrumental parameters for soil analysis were obtained when repetition rate, delay time, and gate width equaled 10 hertz, 1 microsecond, …

Change-Point Analysis: Asymptotic Theory And Applications, Michael Robbins

All Dissertations

The problem of undocumented change-points in data sets appears in many areas of science. Mathematical fundamentals of asymptotic methods used in change-point analysis are discussed, and several important maximally selected change-point statistics are introduced. First, the likelihood ratio method is applied to abstract data models within the setting of precipitation series. Basic inference as to the legitimacy and effectiveness of asymptotic methods at detecting undocumented change-points is provided. Next, maximally selected chi-square statistics are discussed in detail and applied to data on tropical cyclone behavior, where a widely available and widely analyzed data set on Atlantic basin cyclones is studied. …

Discrete Dynamics Over Finite Fields, Jang-Woo Park

All Dissertations

A dynamical system consists of a set V and a map f : V → V . The primary goal is to characterize points in V according to their limiting behaviors under iteration of the map f . Especially understanding dynamics of nonlinear maps is an important but difficult problem, and there are not many methods available. This work concentrates on dynamics of certain nonlinear maps over finite fields. First we study monomial dynamics over finite fields. We show that determining the number of fixed points of a boolean monomial dynamics is #P–complete problem and consider various cases in which …

Development Of Improved Torsional Potentials In Classical Force Field Models Of Poly (Lactic Acid), James Mcaliley

All Dissertations

In this work, existing force field descriptions of poly (lactic acid), or PLA, were improved by modifying the torsional potential energy terms to more accurately model the bond rotational behavior of PLA. Extensive calculations were carried out using density functional theory (DFT), for small PLA molecules in vacuo, and also using DFT with a continuum model to approximate the electronic structure of PLA in its condensed phase. From these results, improved force field parameters were developed using a combination of the OPLS and CHARMM force fields. The new force field, PLAFF2, is an update to the previously developed PLAFF model …

Correction To “The Theory Of Quaternion Orthogonal Designs”, Tadeusz Wysocki, Beata Wysocki, Sarah Spence Adams

Sarah Spence Adams

Seberry et al. claimed that even though the dual-polarized transmission channel cannot be considered as described by means of a single quaternionic gain, the maximum-likelihood (ML) decoding rule can be decoupled for orthogonal space–time-polarization block codes (OSTPBCs) derived from quaternion orthogonal designs (QODs) [1, Sec. IV]. Regretfully, a correction is necessary, and we will show that decoupled decoding using the method presented therein is only optimal for codes derived from certain QODs, not from arbitrary QODs as previously suggested.

A Framework For Technology Transfer, Arcot Desai Narasimhalu

Arcot Desai NARASIMHALU

Technology transfer is often perceived to be transfer of intellectual property (IP). Very few realize that there are other means of transferring technology. Most common means of technology transfer is the transfer of the IP alone. While this is interesting in itself, it is not the best means of transferring technology in all cases. IP such as patents, trademark and copyrighted material can easily be transferred in this manner. However, that is the lowest level of technology transfer possible. The next level of technology transfer is the ability to handover technology from the originating team to the recipient team. This …

The Spectroelectrochemical, Magnetic, And Structural Characterization Of Reduced Hexaazatriphenylenehexacarbonitrile, Hat(Cn)6., Joseph Gallegos, Anthony Francis, Nathan Ockwig, Paul Rasmussen, Raphael Raptis, Paul Challen, Issouf Ouedraogo

Paul R. Challen

The cyanoazacarbon, hexaazatriphenylenehexacarbonitrile, or HAT(CN)6, is readily reduced and the spectroelectrochemical properties associated with the multiple reductions are described. The singly reduced radical monoanion forms stable salts and we report the crystal structure and magnetic properties for the tetrabutylammonium salt. [Tetra-n-butylammonium] [HAT(CN)6] behaves ferromagnetically below 3K and follows Curie Law behavior at higher temperatures after correction for Pauli-type susceptibility. The room temperature conductivity of the powdered salt is 3.8×10−8S/cm. The crystal structure shows closely bound pairs of radical anions with slip-stacking of these pairs to form a staircase, features that elucidate the observed properties. Thin films of HAT(CN)6 were found …

A Sensitivity Matrix Methodology For Inverse Problem Formulation, Ariel Cintron-Arias, H. T. Banks, Alex Capaldi, Alun L. Lloyd

Alex Capaldi

We propose an algorithm to select parameter subset combinations that can be estimated using an ordinary least-squares (OLS) inverse problem formulation with a given data set. First, the algorithm selects the parameter combinations that correspond to sensitivity matrices with full rank. Second, the algorithm involves uncertainty quantification by using the inverse of the Fisher Information Matrix. Nominal values of parameters are used to construct synthetic data sets, and explore the effects of removing certain parameters from those to be estimated using OLS procedures. We quantify these effects in a score for a vector parameter defined using the norm of the …

Lazy-Adaptive Tree: An Optimized Index Structure For Flash Devices, D. Agrawal, D. Ganesan, Ramesh K. Sitaraman, Y. Diao, S. Singh

Ramesh Sitaraman

Flash memories are in ubiquitous use for storage on sensor nodes, mobile devices, and enterprise servers. However, they present significant challenges in designing tree indexes due to their fundamentally different read and write characteristics in comparison to magnetic disks. In this paper, we present the Lazy-Adaptive Tree (LA-Tree), a novel index structure that is designed to improve performance by minimizing accesses to ash. The LA-tree has three key features: 1) it amortizes the cost of node reads and writes by performing update operations in a lazy manner using cascaded buffers, 2) it dynamically adapts buffer sizes to workload using an …

Expanding Photovoltaic Penetration With Residential Distributed Generation From Hybrid Solar Photovoltaic Combined Heat And Power Systems, Joshua M. Pearce

Joshua M. Pearce

Cayley-Dixon Projection Operator For Multi-Univariate Composed Polynomials, Arthur Chtcherba, Deepak Kapur, Manfred Minimair

Manfred Minimair

The Cayley-Dixon formulation for multivariate projection operators (multiples of resultants of multivariate polynomials) has been shown to be efficient (both exper- imentally and theoretically) for simultaneously eliminating many variables from a polynomial system. In this paper, the behavior of the Cayley-Dixon projection op- erator and the structure of Dixon matrices are analyzed for composed polynomial systems constructed from a multivariate system in which each variable is substi- tuted by a univariate polynomial in a distinct variable. Under some conditions, it is shown that a Dixon projection operator of the composed system can be expressed as a power of the resultant …

Radial Distribution Of Stars, Gas, And Dust In Sings Galaxies. Ii. Derived Dust Properties, J.C. Munoz-Mateo, A. Gil De Paz, S. Boissier, J. Zamorano, D.A. Dale, P.G. Perez-Gonzalez, Michele D. Thornley

Michele Thornley

Multiple Loci Within The Major Histocompatibility Complex Confer Risk Of Psoriasis, Bing-Jian Feng, Liang-Dan Sun, Razieh Soltani-Arabshahi, Anne M. Bowcock, Rajan P. Nair, Philip Stuart, James T. Elder, Steven J. Schrodi, Ann B. Begovich, Goncalo R. Abecasis, Xue-Jun Zhang, Kristina P. Callis Duffin, Gerald G. Krueger, David E. Goldgar

Steven J Schrodi

Psoriasis is a common inflammatory skin disease characterized by thickened scaly red plaques. Previously we have performed a genome-wide association study (GWAS) on psoriasis with 1,359 cases and 1,400 controls, which were genotyped for 447,249 SNPs. The most significant finding was for SNP rs12191877, which is in tight linkage disequilibrium with HLA-Cw*0602, the consensus risk allele for psoriasis. However, it is not known whether there are other psoriasis loci within the MHC in addition to HLA-C. In the present study, we searched for additional susceptibility loci within the human leukocyte antigen (HLA) region through in-depth analyses of the GWAS data; …

Statistical Investigation Of Structure In The Discrete Logarithm, Andrew Hoffman

Mathematical Sciences Technical Reports (MSTR)

The absence of an efficient algorithm to solve the Discrete Logarithm Problem is often exploited in cryptography. While exponentiation with a modulus is extremely fast with a modern computer, the inverse is decidedly not. At the present time, the best algorithms assume that the inverse mapping is completely random. Yet there is at least some structure, and to uncover additional structure that may be useful in constructing or refining algorithms, statistical methods are employed to compare modular exponential mappings to random mappings. More concretely, structure will be defined by representing the mappings as functional graphs and using parameters from graph …

Discrete Logarithm Over Composite Moduli, Marcus L. Mace

Mathematical Sciences Technical Reports (MSTR)

In an age of digital information, security is of utmost importance. Many encryption schemes, such as the Diffie-Hellman Key Agreement and RSA Cryptosystem, use a function which maps x to y by a modular power map with generator g. The inverse of this function - trying to find x from y - is called the discrete logarithm problem. In most cases, n is a prime number. In some cases, however, n may be a composite number. In particular, we will look at when n = p^b for a prime p. We will show different techniques of obtaining graphs of this …

Structural Properties Of Power Digraphs Modulo N, Joseph Kramer-Miller

Mathematical Sciences Technical Reports (MSTR)

We define G(n, k) to be a directed graph whose set of vertices is {0, 1, ..., n−1} and whose set of edges is defined by a modular relation. We say that G(n, k) is symmetric of order m if we can partition G(n, k) into subgraphs, each containing m components, such that all the components in a subgraph are isomorphic. We develop necessary and sufficient conditions for G(n, k) to contain symmetry when n is odd and square-free. Additionally, we use group theory to describe the structural properties of the subgraph of G(n, k) containing only those vertices relatively …

Surface Geometry Of C60 On Ag(111), H. I. Li, K. Pussi, K. J. Hanna, Lin-Lin Wang, Duane D. Johnson, H.-P. Cheng, H. Shin, S. Curtarolo, W. Moritz, J. A. Smerdon, R. Mcgrath, R. D. Diehl

Duane D. Johnson

The geometry of adsorbed C60 influences its collective properties. We report the first dynamical low-energy electron diffraction study to determine the geometry of a C60 monolayer, Ag(111)−(23√×23√)30°−C60, and related density functional theory calculations. The stable monolayer has C60 molecules in vacancies that result from the displacement of surface atoms. C60 bonds with hexagons down, with their mirror planes parallel to that of the substrate. The results indicate that vacancy structures are the rule rather than the exception for C60 monolayers on close-packed metal surfaces.

Preparing For A Changing And Variable Climate, Glynn Ward

Research Reports

Climate change has the potential to reshape the Australian wine industry. Regions will be differentially impacted and will respond according to their unique viticultural, environmental, economic and social characteristics. An industry forum and regional workshop series was held in Western Australia focusing on three wine regions: Margaret River, Pemberton and Mount Barker. Fine scale climate information (mesoscale maps) and overviews of current and emerging technologies and resources that can be used by the wine industry to plan for and manage the risks and opportunities resulting from a changing and variable climate were presented. The information indicated that the wine regions …

Preparing For A Changing And Variable Climate: Final Report To Grape And Wine Research And Development Corporation Rt 07/02-2, Glynn Ward

All other publications

Climate change has the potential to reshape the Australian wine industry. Regions will be differentially impacted and will respond according to their unique viticultural, environmental, economic and social characteristics. An industry forum and regional workshop series was held in Western Australia focusing on three wine regions: Margaret River, Pemberton and Mount Barker. Fine scale climate information (mesoscale maps) and overviews of current and emerging technologies and resources that can be used by the wine industry to plan for and manage the risks and opportunities resulting from a changing and variable climate were presented. The information indicated that the wine regions …

Generating Derivative Structures From Multilattices: Algorithm And Application To Hcp Alloys, Gus L. W. Hart, Rodney W. Forcade

Faculty Publications

We present an algorithm for generating all derivative superstructures of a nonprimitive parent lattice. The algorithm has immediate application in important materials design problems such as modeling hexagonal-close-packed (hcp) alloys. Extending the work of Hart and Forcade [Phys. Rev. B 77, 224115 (2008)] (which applies only to Bravais lattices), this approach applies to arbitrary multilattices. The algorithm enumerates superlattices and atomic configurations using permutation groups rather than direct geometric comparisons. The key concept is to use the quotient group associated with each superlattice to determine all unique atomic configurations. The algorithm is very efficient; the run time scales linearly with …