Physical Sciences and Mathematics Commons^™

Secondary Enrichment Of Copper At The Madison Gold Skarn Deposit, Silver Star District, Montana, Christopher H. Gammons, Jill Sotendahl, Dan Everett

Geological Engineering

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana. This paper focuses on the chemical reactions responsible for secondary enrichment of copper...we argue that most of the secondary Cu enrichment occurred during a late hydrothermal event that replaced the high temperature skarn mineral assemblage with hematitic jasperoid. Evidence favoring this "hypogene" Cu enrichment hypothesis is presented.

Noninvasive, In-Vivo, Tissue Modulated Near Infrared Spectroscopy Of Fingertips: Resonance Raman Spectrum Of Human Hemoglobin, Bin Deng, Jerry Goodisman, George Shaheen, Rebecca J. Bussjager, Joseph Chaiken

Chemistry - All Scholarship

Tissue modulation refers to using external stimuli such as mechanical pressure and temperature to produce various spatiotemporal distributions of blood and conceivably other fluids in tissues. Having the capacity to execute tissue modulation¹ allows forms of difference spectroscopy to be used to isolate spectroscopic signals from specific components of the tissues noninvasively and in vivo. In the case of human fingertips we can think of the tissues present in the probed volume as being static tissue, plasma and red blood cells (RBCs). Static tissues deform under mechanical pressure based tissue modulation and the only possible fluid motions2 involve plasma …

Choosing Management Information Systems As A Major: Understanding The Smifactors For Mis, Thomas W. Ferratt, Stephen R. Hall, Jayesh Prasad, Donald E. Wynn

MIS/OM/DS Faculty Publications

Given declining management information systems (MIS) enrollments at our university, we seek to understand our students‘ selection of a major. Prior studies have found that students choose a major based on a number of factors, with subject matter interest consistently being most important. We contribute to the literature by developing a deeper understanding of what is meant by subject matter interest, which we refer to as smiFactors, for MIS as a major and career. Based on a qualitative analysis of open-ended survey questions completed by undergraduate business students, we confirm a number of smiFactors for MIS gleaned from recent studies …

Numerical Methods For Fmri Data Analysis, Geethmala Sridaran

Dartmouth College Master’s Theses

Brain imaging data are increasingly analyzed via a range of machine-learning methods. In this thesis, we discuss three specific contributions to the field of neuroimaging analysis methods: 1. To apply a recently-developed technique for identifying and viewing similarity structure in neuroimaging data, in which candidate representational structures are ranked; 2. Provide side-by-side analyses of neuroimaging data by a typical non-hierarchical (SVM) versus hierarchical (Decision Tree) machine-learning classification methods; and 3. To develop a novel programming environment for PyMVPA, a current popular analysis toolbox, such that users will be able to type a small number of packaged commands to carry out …

Ads/Cft Correspondence And Hydrodynamics Of Relativistic Heavy Ion Collisions, James Ethan Alsup

Doctoral Dissertations

The experiments performed at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Lab have discovered a state of matter called the strongly coupled quark-gluon plasma (sQGP). The strong coupling has limited the ability of the standard theory to describe such matter, namely Quantum Chromodynamics (QCD). However, string theory's anti-de Sitter/conformal field theory (AdS/CFT) correspondence has provided a new way to study the situation and in an analytical manner. So far, hydrodynamic properties of RHIC's plasma, such as elliptic flow and longitudinal expansion, have been seen to follow from classical supergravity calculations. In this dissertation I discuss some of the …

Hairy Particles: Polymer Brush-Supported Organocatalysts And Asymmetric Mixed Homopolymer Brushes, Xiaoming Jiang

Doctoral Dissertations

This dissertation presents the synthesis and studies of polymer brush-supported organocatalysts and asymmetric mixed homopolymer brushes grafted on particles. The brushes were synthesized from initiator-functionalized particles by surface-initiated “living” radical polymerizations.

Polymer brush-supported organocatalysts were designed to combine the advantages of both soluble polymer- (high activity) and crosslinked insoluble polymer-supported catalysts (recyclability). Chapter 1 describes the synthesis of a polymer brush-supported 4-N,N-dialkylaminopyridine (DAAP) catalyst from initiator-functionalized latex particles by surface-initiated nitroxide-mediated radical polymerization (NMRP). The hairy particles efficiently catalyzed the acylation of secondary alcohols and Baylis-Hillman reaction and were recycled  six times with no or negligible decrease in the …

Wind Power And Human Health: Flicker, Noise, And Air Quality, Erik Nordman

Technical Reports

The second of a series of wind energy issue briefs synthesizes the state of the science around wind energy siting issues like flicker and noise, and analyzes how West Michigan communities are addressing these challenges. The issue brief also assesses how wind energy could improve air quality and human health outcomes in West Michigan and the region.

4-Bromo-N 2,N 2,N 6,N 6-Tetra­Ethyl­Pyridine-2,6-Dicarboxamide, Daniel T. De Lill, Ana De Bettencourt-Dias

Chemistry and Physics Faculty Articles

The title compound, C₁₅H₂₂BrN₃O₂, consists of a pyridine ring with a bromine atom in the para position and two diethyl­amide groups in the ortho positions of the ring. Despite the positions of the three substituents on the pyridine ring, the mol­ecule does not exhibit either local or crystallographic twofold symmetry as the two diethyl­amido units exhibit significantly different N_py—C—C—N_am torsion angles of 46.3 (4) and 62.7 (4)° (py is pyridine and am is amine). Inter­molecular C—H⋯O inter­actions support the packing.

How Lightning Tortuosity Affects The Electromagnetic Fields By Augmenting Their Effective Distance, S L. Meredith, S K. Earles, I N. Kostanic, Niescja E. Turner, C E. Otero

Physics and Astronomy Faculty Research

A novel approach for developing the electromagnetic fields from a lightning return stroke which follows a tortuous path will be presented. The proposed model is unique in that it recognizes that the symmetrical tortuosity of lightning directly impacts the observable distance r, which in turn, alters the resulting electromagnetic fields. In the literature, lightning return stroke models typically employ the assumption that the cloud-to-ground path is straight. Although this assumption yields fairly consistent results across an array of varying approaches, it does not account for lightning's natural physical appearance. Furthermore, straight-line models only account for the cloud-to-ground discharges and do …

Green’S Functions And The Adiabatic Hyperspherical Method, Seth T. Rittenhouse, Nirav P. Mehta, Chris H. Greene

Physics and Astronomy Faculty Research

We address the few-body problem using the adiabatic hyperspherical representation. A general form for the hyperangular Green’s function in d dimensions is derived. The resulting Lippmann-Schwinger equation is solved for the case of three particles with s-wave zero-range interactions. Identical particle symmetry is incorporated in a general and intuitive way. Complete semianalytic expressions for the nonadiabatic channel couplings are derived. Finally, a model to describe the atom loss due to three-body recombination for a three-component Fermi gas of ⁶Li atoms is presented.

Acyl-Chain Mismatch Driven Superlattice Arrangements In Dppc/Dlpc/Cholesterol Bilayers, Brian Cannon, Anthony Lewis, Pentti Somerharju, Jorma Virtanen, Juyang Huang, Kwan H. Cheng

Physics and Astronomy Faculty Research

Fluorescence and infrared spectroscopy and cholesterol oxidase activity were employed to investigate the effect of phosphatidylcholine (PC) acyl chain length mismatch on the lateral organizations of lipids in liquid-ordered dipalmitoyl-PC/dilauroyl-PC/cholesterol (DPPC/DLPC/CHOL) bilayers. Plots of steady-state fluorescence emission anisotropy of diphenylhexatriene (DPH) labeled PC (DPH-PC) embedded in the DPPC/DLPC/CHOL bilayers revealed significant peaks at several DPPC mole fractions (Y_DPPC) when the cholesterol mole fraction (X_CHOL) was fixed to particular values. Analogously, the DPH-PC anisotropy peaked at several critical X_CHOL’s when Y_DPPC was fixed. Acyl chain C−H and C═O vibrational peak frequencies of …

Automated Theorem Prover Axiom Management, Ashley T. Holeman, Ewen Denney

STAR Program Research Presentations

Automated Theorem Provers (ATPs), are computer programs that use collections of axioms,which are logical statements assumed to be true, in order to prove conjectures. NASA uses these programs to verify safety and functional requirements in domains like Guidance, Navigation, and Control. There are about 30 axioms on each major topic including the theory of coordinate systems, elementary arithmetic and linear algebra. These axioms have been created over the duration of many projects and combined into a single file. One task is to manage the axioms by arranging them into logical sections, deleting unnecessary ones and rewriting some into a more …

On Numerical Solutions Of Two-Dimensional Boussinesq Equations By Using Adomian Decomposition And He's Homotopy Perturbation Method, Syed T. Mohyud-Din, Mustafa Inc, Ebru Cavlak

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we obtain the approximate solution for 2-dimensional Boussinesq equation with initial condition by Adomian's decomposition and homotopy perturbation methods and numerical results are compared with exact solutions.

A Note On He’S Parameter-Expansion Method Of Coupled Van Der Pol–Duffing Oscillators, N. H. Sweilam, M. M. Khader

Applications and Applied Mathematics: An International Journal (AAM)

This paper presents the analytical and approximate solutions of the coupled chaotic Van der Pol-Duffing systems, by using the He's parameter-expansion method (PEM). One iteration is sufficient to obtain a highly accurate solution, which is valid for the whole solution domain. From the obtained results, we can conclude that the suggest method, is of utter simplicity, and can be easily extended to all kinds of non-linear equations.

Exact Solitary-Wave Special Solutions For The Nonlinear Dispersive K(M,N) Equations By Means Of The Homotopy Analysis Method, Ahmet Yıldırım, Canan Ünlü, Syed T. Mohyud-Din

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we study the nonlinear dispersive K(m,n) equations which exhibit solutions with solitary patterns. New exact solitary solutions are found. The two special cases, K(2, 2) and K(3, 3), are chosen to illustrate the concrete features of the homotopy analysis method in K(m,n) equations. The nonlinear equations K(m,n) are studied for two different cases, namely when m = n being odd and even integers. General formulas for the solutions of K(m,n) equations are established.

Homotopy Perturbation Method And The Stagnation Point Flow, P. Donald Ariel

Applications and Applied Mathematics: An International Journal (AAM)

The laminar steady flow of an incompressible, viscous fluid near a stagnation point has been computed using the homotopy perturbation method (HPM). Both the cases, (i) two-dimensional flow and (ii) axisymmetric flow, have been considered. A sequence of successive approximations has been obtained in the solution, and the convergence of the sequence is achieved by using the Padé approximants. It is found that there is a complete agreement between the results obtained by the HPM and the exact numerical solution.

Performance Measures In Acousto-Optic Chaotic Signal Encryption System Subject To Parametric Variations And Additive Noise, Monish Ranjan Chatterjee, Anjan K. Ghosh, Mohammed A. Al-Saedi

Electrical and Computer Engineering Faculty Publications

Signal encryption and recovery using chaotic optical waves has been a subject of active research in the past 10 years. Since an acousto-optic Bragg cell with zeroth- and first-order feedback exhibits chaotic behavior past the threshold for bistability, such a system was recently examined for possible chaotic encryption using a low-amplitude sinusoidal signal applied via the bias input of the sound cell driver.

Subsequent recovery of the message signal was carried out via a heterodyne strategy employing a locally generated chaotic carrier, with threshold parameters matched to the transmitting Bragg cell. The simulation results, though encouraging, were limited to relatively …

A Global Characterization Of Tubed Surfaces In ℂ2, Michael Bolt

University Faculty Publications and Creative Works

Let M3 S C2 be a three times differentiable real hypersurface. The Levi form of M transforms under biholomorphism, and when restricted to the complex tangent space, the skew-Hermitian part of the second fundamental form transforms under Möbius transformations. The surfaces for which these forms are constant multiples of each other were identified in previous work, provided the constant is not unimodular. Here it is proved that if the surface is assumed to be complete and if the constant is unimodular, then the surface is tubed over a strongly convex curve. The converse statement is true, too, and is easily …

An Examination Of Heritage Resource Internship Experiences And Land Management Agency's Role In Inspiring Emerging Leaders, Carin Vadala

All Dissertations

To address the shortage of people seeking to fill employment vacancies, the land management agencies are using the Student Conservation Association (SCA) and internships as a means of recruiting the next generation of leaders. Yet little research has been conducted on internships in cultural and natural heritage resource parks. This study used a two-phase linear exploratory method to investigate the experiences of cultural and natural heritage resource interns. Additionally, the study sought to determine if and how internships shape vocational, recreational, social and personal identities concerning parks and protected areas. Using significant life experiences, environmental socialization and emerging adulthood theories, …

Chemical Modification And Biological Activity Exploration Of The Natural Product-Gossypol, Juanjuan Yin

All Dissertations

Gossypol is a naturally occurring, highly colored yellow pigment indigenous to the small intercellular pigment glands of the cotton plant genus Gossypium, which is proposed to be part of plant's defense system. Gossypol is characterized by wide contraceptive, antiviral, anticancer and antifungal properties. However, the relatively high toxicity of gossypol precludes its application in medical therapy. For this reason the syntheses and tests of gossypol derivatives, have been tried to enable their application as drugs. In our study, gossypol based methylation, glycosylation and nanoconjugate reactions were explored. The gossypol derivatives were all fully characterized by NMR, MS, FT-IR, UV spectrometry, …

Perfluoroalkyl Phosphonic And Phosphinic Acid Electrolytes For Proton Exchange Membrane Fuel Cells, Mahesha Herath

All Dissertations

Perfluorinated sulfonic acid polymers have been considered as the state-of-art membrane materials for proton exchange membrane fuel cells. A major technical issue with these polymers is that they do not function well at temperatures above 80 °C and at low humidities. Therefore, research has been focused on developing PEM materials that can operate independent of hydration requirements. The operation of fuel cells at high temperature (e.g. 120 oC) increases fuel cell system efficiency due to faster electrode kinetics and better CO tolerance. This dissertation will describe a study of proton-transport rates and mechanisms under anhydrous and aqueous conditions using a …

Observing Co In Circumstellar Disks, Matthew Troutman

All Dissertations

This dissertation includes high-resolution, near-infrared spectroscopy to study CO in circumstellar disks around Herbig Ae/Be stars. The velocity-resolved spectra was used to measure the distribution of gas in the circumstellar disk and thus determine the evolutionary state of the system. Near-infrared spectra were obtained on over 30 young circumstellar disks around Herbig Ae/Be stars to study the physical processes in the disk. The radial location of the CO emitting gas bears directly on the evolutionary state of the transition objects in the sample. This study included a detailed study of the debris disk star β Pictoris where the disk mass …

Event-Driven Similarity And Classification Of Scanpaths, Thomas Grindinger

All Dissertations

Eye tracking experiments often involve recording the pattern of deployment of visual attention over the stimulus as viewers perform a given task (e.g., visual search). It is useful in training applications, for example, to make available an expert's sequence of eye movements, or scanpath, to novices for their inspection and subsequent learning. It may also be potentially useful to be able to assess the conformance of the novice's scanpath to that of the expert. A computational tool is proposed that provides a framework for performing such classification, based on the use of a probabilistic machine learning algorithm. The approach was …

Effects Of Imperviousness On Family Biotic Index Values In The Southern Appalachian Headwaters And Resulting Extension Education, Jon Calabria

All Dissertations

Clear, cool headwater streams in the mountains of North Carolina are inextricably linked to the surrounding landscape. Trickling perennial streams drain precipitation from their catchment and are capable of sustaining excellent water quality to support rich aquatic biodiversity that feeds and beneficially contributes to the stream network below. However, headwater ecosystems can be easily compromised by even seemingly insignificant anthropogenic impacts. Small headwater streams were not mapped until recently, and are now known to be ubiquitous. Although the NC Mountains contain some of the highest headwater streams densities in the nation, they remain very susceptible to changes in the catchments …

An Approximate Analytical Solution Of The Fractional Diffusion Equation With External Force And Different Type Of Absorbent Term - Revisited, S. Das, R. Kumar, P. K. Gupta

Applications and Applied Mathematics: An International Journal (AAM)

In this article Homotopy Perturbation Method (HPM) is applied to obtain an approximate analytical solution of a fractional diffusion equation with an external force and a reaction term different from the reaction term used by Das and Gupta (2010). The anomalous behavior of diffusivity in presence or absence of linear external force due to the presence of this force of reaction term are obtained and presented graphically.

Top Quark Pair And Single Top Production At Tevatron And Lhc Energies, Nikolaos Kidonakis

Faculty Articles

I present the latest calculations of total and differential cross sections for top-antitop pair production and single top quark production via all main partonic channels. Higher-order corrections from the resummation of soft gluons are added through NNLL accuracy. Detailed numerical results are presented for approximate NNLO cross sections and top quark transverse momentum distributions at the Tevatron and LHC colliders.

Molecular Orbitals And Organic Chemical Reactions (Book Review), Jeffrey H. Glans

Chemistry & Physics Faculty Publications

Book review by Jeffrey Glans.

Fleming, Ian. Molecular Orbitals and Organic Chemical Reactions. Wiley-Blackwell, 2010, c2009.

ISBN: 9780470746608; 9780470746592 (pbk.)

Team Performance Prediction In Massively Multiplayer Online Role-Playing Games (Mmorpgs), Kyong Jin Shim, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

In this study, we propose a comprehensive performance management tool for measuring and reporting operational activities of teams. This study uses performance data of game players and teams in EverQuest II, a popular MMORPG developed by Sony Online Entertainment, to build performance prediction models for task performing teams. The prediction models provide a projection of task performing team's future performance based on the past performance patterns of participating players on the team as well as team characteristics. While the existing game system lacks the ability to predict team-level performance, the prediction models proposed in this study are expected to be …

Theoretical Fully Differential Cross Sections For Double-Charge-Transfer Collisions, Allison L. Harris, Jerry Peacher, Don H. Madison

Physics Faculty Research & Creative Works

We present a four-body model for double charge transfer, called the four-body double-capture model. This model explicitly treats all four particles in the collision, and we apply it here to fully differential cross sections (FDCSs) for proton+helium collisions. The effects of initial- and final-state electron correlations are studied, as well as the role of the projectile-nucleus interaction. We also present results for proton+helium single capture, as well as single-capture:double-capture ratios of FDCSs.

Anomalously Elastic Intermediate Phase In Randomly Layered Superfluids, Superconductors, And Planar Magnets, Priyanka Mohan, Paul M. Goldbart, Rajesh Narayanan, John Toner, Thomas Vojta

Physics Faculty Research & Creative Works

We show that layered quenched randomness in planar magnets leads to an unusual intermediate phase between the conventional ferromagnetic low-temperature and paramagnetic high-temperature phases. In this intermediate phase, which is part of the Griffiths region, the spin-wave stiffness perpendicular to the random layers displays anomalous scaling behavior, with a continuously variable anomalous exponent, while the magnetization and the stiffness parallel to the layers both remain finite. Analogous results hold for superfluids and superconductors. We study the two phase transitions into the anomalous elastic phase, and we discuss the universality of these results, and implications of finite sample size as well …