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Intonation And Compensation Of Fretted String Instruments, Gabriele U. Varieschi, Christina M. Gower 2010 Loyola Marymount University

Intonation And Compensation Of Fretted String Instruments, Gabriele U. Varieschi, Christina M. Gower

Physics Faculty Works

We discuss theoretical and physical models that are useful for analyzing the intonation of musical instruments such as guitars and mandolins and can be used to improve the tuning on these instruments. The placement of frets on the fingerboard is designed according to mathematical rules and the assumption of an ideal string. The analysis becomes more complicated when we include the effects of deformation of the string and inharmonicity due to other string characteristics. As a consequence, perfect intonation of all the notes on the instrument cannot be achieved, but complex compensation procedures can be introduced to minimize the problem ...


Design And Fabrication Of Holographic Optical Elements For Applications In Electronic Speckle Pattern Interferometry And Laser Doppler Vibrometry, Viswanath Bavigadda, Emilia Mihaylova, Raghavendra Jallapuram, Vincent Toal 2010 Technological University Dublin

Design And Fabrication Of Holographic Optical Elements For Applications In Electronic Speckle Pattern Interferometry And Laser Doppler Vibrometry, Viswanath Bavigadda, Emilia Mihaylova, Raghavendra Jallapuram, Vincent Toal

Conference Papers

An important area of application of holographic optical elements (HOEs) is in optical and electronic speckle pattern interferometry. The design, fabrication and characterization of holographic optical elements (HOEs) for electronic speckle pattern interferometry are presented. Reflection HOEs (RHOEs) were fabricated for use in electronic speckle pattern interferometers (ESPI) and laser Doppler vibrometers (LDV). The HOE-based interferometer is sensitive to out-of-plane displacements only. The results obtained are promising for future applications of the system for modal analysis.


Low-Temperature Adsorption Of H2s On Ag(111), Selena M. Russell, Da-Jiang Liu, Maki Kawai, Yousoo Kim, Patricia A. Thiel 2010 Iowa State University

Low-Temperature Adsorption Of H2s On Ag(111), Selena M. Russell, Da-Jiang Liu, Maki Kawai, Yousoo Kim, Patricia A. Thiel

Chemistry Publications

H2S forms a rich variety of structures on Ag(111) at low temperature and submonolayer coverage. The molecules decorate step edges, exist as isolated entities on terraces, and aggregate into clusters and islands, under various conditions. One type of island exhibits a (×)R25.3° unit cell. Typically, molecules in the clusters and islands are separated by about 0.4 nm, the same as the S–S separation in crystalline H2S. Density functional theory indicates that hydrogen-bonded clusters contain two types of molecules. One is very similar to an isolated adsorbed H2S molecule, with both ...


Periodic Step Arrays On The Aperiodic I-Al-Pd-Mn Quasicrystal Surface At High Temperature, Y. Sato, Barış Ünal, Thomas A. Lograsso, Patricia A. Thiel, A. K. Schmid, T. Duden, N. C. Bartelt, K. F. McCarty 2010 University of California, Davis

Periodic Step Arrays On The Aperiodic I-Al-Pd-Mn Quasicrystal Surface At High Temperature, Y. Sato, Barış Ünal, Thomas A. Lograsso, Patricia A. Thiel, A. K. Schmid, T. Duden, N. C. Bartelt, K. F. Mccarty

Chemistry Publications

We have observed the configuration and motion of surface steps on the aperiodic icosahedral (i-) Al-Pd-Mn quasicrystal using low-energy electron microscopy and scanning tunneling microscopy. As the quasicrystal is cooled from high temperature, bulk vacancies migrate to the surface causing the surface to be etched. Surprisingly, this etching occurs by two types of steps with different heights moving in different directions with different velocities. The steady-state surface morphology is a uniformly spaced rhomboidal step network. This network requires that the layer stacking near the surface deviates from the bulk quasicrystal stacking.


Rhombohedrally Distorted Γ-Brasses Cr1−Xfexga, Hyujin Ko, Olivier Gourdon, Delphine Gout, Eun-Deok Mun, Srinivasa Thimmaiah, Gordon J. Miller 2010 Iowa State University

Rhombohedrally Distorted Γ-Brasses Cr1−Xfexga, Hyujin Ko, Olivier Gourdon, Delphine Gout, Eun-Deok Mun, Srinivasa Thimmaiah, Gordon J. Miller

Chemistry Publications

A series of rhombohedrally distorted γ-brass structures containing a mixture of magnetically active 3d elements, Cr and Fe, Cr1−xFexGa, is investigated crystallographically. These structures consist of chains of trans-face-sharing Ga-centered transition metal icosahedra. Neutron powder diffraction specifically on Cr0.5Fe0.5Ga, which could be prepared as a single phase material, gave lattice constants (11 K) a = 12.5172(2) Å and c = 7.8325(2) Å and a refined composition of Cr0.502(6)Fe0.498Ga = Cr6.523Fe6.477Ga13 and revealed partial ordering ...


Space Weather & Gps Reliant Industries, Jennifer L. Meehan, W. Murtagh 2010 Utah State University

Space Weather & Gps Reliant Industries, Jennifer L. Meehan, W. Murtagh

All Physics Faculty Publications

No abstract provided.


Methods To Determine Total Electron-Induced Electron Yields Over Broad Range Ofconductive And Nonconductive Materials, Ryan C. Hoffmann, JR Dennison 2010 Air Force Research Laoratory

Methods To Determine Total Electron-Induced Electron Yields Over Broad Range Ofconductive And Nonconductive Materials, Ryan C. Hoffmann, Jr Dennison

All Physics Faculty Publications

The electron emission properties of a material subject to incident radiation flux are key parameters in determining to what equilibrium charge a spacecraft will established under given environmental conditions. However, there is a complex relation between these emission properties and the charge built up in spacecraft insulators. Complex modeling codes have been developed to predict the potential a spacecraft will adopt as a consequence of its interaction with the space plasma. These require correct models of the electron yields as a function of charge to accurately predict the both the charge build up and the equilibrium potential of spacecraft components ...


Experimental And Theoretical Approaches To Characterization Of Electronic Nonlinearities In Direct-Gap Semiconductors, Claudiu Cirloganu 2010 University of Central Florida

Experimental And Theoretical Approaches To Characterization Of Electronic Nonlinearities In Direct-Gap Semiconductors, Claudiu Cirloganu

Electronic Theses and Dissertations, 2004-2019

The general goal of this dissertation is to provide a comprehensive description of the limitations of established theories on bound electronic nonlinearities in direct-gap semiconductors by performing various experiments on wide and narrow bandgap semiconductors along with developing theoretical models. Nondegenerate two-photon absorption (2PA) is studied in several semiconductors showing orders of magnitude enhancement over the degenerate counterpart. In addition, three-photon absorption (3PA) is studied in ZnSe and other semiconductors and a new theory using a Kane 4-band model is developed which fits new data well. Finally, the narrow gap semiconductor InSb is studied with regard to multiphoton absorption, free-carrier ...


Development Of Optical Coherence Tomography For Tissue Diagnostics, Panomsak Meemon 2010 University of Central Florida

Development Of Optical Coherence Tomography For Tissue Diagnostics, Panomsak Meemon

Electronic Theses and Dissertations, 2004-2019

Microvasculature can be found in almost every part of the human body, including the internal organs. Importantly, abnormal changes in microvasculature are usually related to pathological development of the tissue cells. Monitoring of changes in blood flow properties in microvasculature, therefore, provides useful diagnostic information about pathological conditions in biological tissues as exemplified in glaucoma, diabetes, age related macular degeneration, port wine stains, burn-depth, and potentially skin cancer. However, the capillary network is typically only one cell in wall thickness with 5 to 10 microns in diameter and located in the dermis region of skin. Therefore, a non-invasive flow imaging ...


Accelerating Optical Airy Beams, Georgios Siviloglou 2010 University of Central Florida

Accelerating Optical Airy Beams, Georgios Siviloglou

Electronic Theses and Dissertations, 2004-2019

Over the years, non-spreading or non-diffracting wave configurations have been systematically investigated in optics. Perhaps the best known example of a diffraction-free optical wave is the so-called Bessel beam, first suggested and observed by Durnin et al. This work sparked considerable theoretical and experimental activity and paved the way toward the discovery of other interesting non-diffracting solutions. In 1979 Berry and Balazs made an important observation within the context of quantum mechanics: they theoretically demonstrated that the Schrodinger equation describing a free particle can exhibit a non-spreading Airy wavepacket solution. This work remained largely unnoticed in the literature-partly because such ...


Near-Field Optical Interactions And Applications, David Haefner 2010 University of Central Florida

Near-Field Optical Interactions And Applications, David Haefner

Electronic Theses and Dissertations, 2004-2019

The propagation symmetry of electromagnetic fields is affected by encounters with material systems. The effects of such interactions, for example, modifications of intensity, phase, polarization, angular spectrum, frequency, etc. can be used to obtain information about the material system. However, the propagation of electromagnetic waves imposes a fundamental limit to the length scales over which the material properties can be observed. In the realm of near-field optics, this limitation is overcome only through a secondary interaction that couples the high-spatial-frequency (but non-propagating) field components to propagating waves that can be detected. The available information depends intrinsically on this secondary interaction ...


Adsorbate-Enhanced Transport Of Metals On Metal Surfaces: Oxygen And Sulfur On Coinage Metals, Patricia A. Thiel, Mingmin Shen, Da-Jiang Liu, James W. Evans 2010 Iowa State University

Adsorbate-Enhanced Transport Of Metals On Metal Surfaces: Oxygen And Sulfur On Coinage Metals, Patricia A. Thiel, Mingmin Shen, Da-Jiang Liu, James W. Evans

Chemistry Publications

Coarsening (i.e., ripening) of single-atom-high, metal homoepitaxial islands provides a useful window on the mechanism and kinetics of mass transport at metal surfaces. This article focuses on this type of coarsening on the surfaces of coinage metals (Cu, Ag, Au), both clean and with an adsorbed chalcogen (O, S) present. For the clean surfaces, three aspects are summarized: (1) the balance between the two major mechanisms—Ostwald ripening (the most commonly anticipated mechanism) and Smoluchowski ripening—and how that balance depends on island size; (2) the nature of the mass transport agents, which are metal adatoms in almost all ...


Geometric Symmetries In Superfluid Vortex Dynamics, E Kozik, Boris Svistunov 2010 University of Massachusetts - Amherst

Geometric Symmetries In Superfluid Vortex Dynamics, E Kozik, Boris Svistunov

Physics Department Faculty Publication Series

Dynamics of quantized vortex lines in a superfluid feature symmetries associated with the geometric character of the complex-valued field, w(z)=x(z)+iy(z), describing the instant shape of the line. Along with a natural set of Noether’s constants of motion, which—apart from their rather specific expressions in terms of w(z)—are nothing but components of the total linear and angular momenta of the fluid, the geometric symmetry brings about crucial consequences for kinetics of distortion waves on the vortex lines, the Kelvin waves. It is the geometric symmetry that renders Kelvin-wave cascade local in the ...


Characterization And Correction Of Dark Current In Compact Consumer Cameras, Justin Charles Dunlap, Erik Bodegom, Ralf Widenhorn 2010 Portland State University

Characterization And Correction Of Dark Current In Compact Consumer Cameras, Justin Charles Dunlap, Erik Bodegom, Ralf Widenhorn

Physics Faculty Publications and Presentations

A study of dark current in digital imagers within consumer grade digital cameras is presented. Dark current is shown to vary with temperature, exposure time, and ISO setting. Further, dark current is shown to increase in successive images during a series of images. Consumer cameras are often designed to be as compact as possible and therefore the digital imagers within the camera frame are prone to heat generated by nearby elements within the camera body. It is the scope of this work to characterize the dark current in such cameras and to show that the dark current, in part due ...


Does Chiasmus Appear In The Book Of Mormon By Chance?, Boyd F. Edwards, W. F. Edwards 2010 Utah State University

Does Chiasmus Appear In The Book Of Mormon By Chance?, Boyd F. Edwards, W. F. Edwards

All Physics Faculty Publications

Chiasmus is an inverted-parallel literary form that was employed by ancient Hebrew biblical writers, among others. An instance of this form, called a “chiasm,” presents two or more literary elements, and then restates them in reverse order. Short chiasms are not uncommon in literature. In some cases, the authors undoubtedly intended to use that form for literary effect (that is, by design); in other cases, the elements fell into that form without author intent (that is, by chance). In 1969, John W. Welch reported his discovery of many-element chiasms in the Book of Mormon,1 which Joseph Smith testified to ...


Temperature Trends And Episodic Changes Of The Middle Atmosphere Over Logan Utah With Consideration To Model Specification, Troy A. Wynn, Vincent B. Wickwar 2010 Utah State University

Temperature Trends And Episodic Changes Of The Middle Atmosphere Over Logan Utah With Consideration To Model Specification, Troy A. Wynn, Vincent B. Wickwar

Reports

A summary of the linear trends estimated from the USU Rayleigh Lidar (41.74o N, 118oW) temperature data set. The data set covers a time span from September, 1993 to August, 2003 and an altitude range of 45 to 80 km. The data set includes 584 data points at 45 km to 580 data points at 80 km. Cooling trend profiles are calculated and compared to results from other researchers. Collinearity and bias are also considered as issues that could affect the regression results. Also considered is the possibility that the Mt. Pinatubo eruption has influenced temperature trend estimates. This ...


Evaluation Of The Potential Of Raman Microspectroscopy For Prediction Of Chemotherapeutic Response To Cisplatin In Lung Adenocarcinoma, Haq Nawaz, Franck Bonnier, Peter Knief, Orla Howe, Fiona Lyng, Aidan Meade, Hugh Byrne 2010 Technological University Dublin

Evaluation Of The Potential Of Raman Microspectroscopy For Prediction Of Chemotherapeutic Response To Cisplatin In Lung Adenocarcinoma, Haq Nawaz, Franck Bonnier, Peter Knief, Orla Howe, Fiona Lyng, Aidan Meade, Hugh Byrne

Articles

The study of the interaction of anticancer drugs with mammalian cells in vitro is important to elucidate the mechanisms of action of the drug on its biological targets. In this context, Raman spectroscopy is a potential candidate for high throughput, noninvasive analysis. To explore this potential, the interaction of cis-Diamminedichloroplatinum (II) (Cisplatin) with a human lung adenocarcinoma cell line (A549) was investigated using Raman microspectroscopy. The results were correlated with parallel measurements from the MTT cytotoxicity assay, which yielded an IC50 value of 1.2±0.2 μM. To further confirm the spectral results, Raman spectra were also acquired from ...


Direct Measurements Of Island Growth And Step-Edge Barriers In Colloidal Epitaxy, Rajesh Ganapathy, Mark R. Buckley, Sharon J. Gerbode, Itai Cohen 2010 Cornell University

Direct Measurements Of Island Growth And Step-Edge Barriers In Colloidal Epitaxy, Rajesh Ganapathy, Mark R. Buckley, Sharon J. Gerbode, Itai Cohen

All HMC Faculty Publications and Research

Epitaxial growth, a bottom-up self-assembly process for creating surface nano- and microstructures, has been extensively studied in the context of atoms. This process, however, is also a promising route to self-assembly of nanometer- and micrometer-scale particles into microstructures that have numerous technological applications. To determine whether atomic epitaxial growth laws are applicable to the epitaxy of larger particles with attractive interactions, we investigated the nucleation and growth dynamics of colloidal crystal films with single-particle resolution. We show quantitatively that colloidal epitaxy obeys the same two-dimensional island nucleation and growth laws that govern atomic epitaxy. However, we found that in colloidal ...


Two Particle Correlations And The Ridge In Relativistic Heavy Ion Collisions, George Stevens Moschelli 2010 Wayne State University

Two Particle Correlations And The Ridge In Relativistic Heavy Ion Collisions, George Stevens Moschelli

Wayne State University Dissertations

Measurements at the Relativistic Heavy Ion Collider (RHIC) find an enhancement of two particle correlations in relativistic heavy ion collisions, not present in proton-proton collisions. Because the correlation structure is wide in relative pseudorapidity and narrow in relative azimuthal angle, it is known as the ridge. The most striking feature of the ridge is that it seems to extend to a long range in relative pseudorapidity where causality limits interaction. Similar ridge structures are observed in correlations of particles associated with and without a jet trigger. We argue that the untriggered ridge arises when particles formed in an early Glasma ...


A Study Of Structure-Property Correlation In V2o5 And Tio2 Based Thin Films As Functional Materials, Chandra Thapa 2010 Wayne State University

A Study Of Structure-Property Correlation In V2o5 And Tio2 Based Thin Films As Functional Materials, Chandra Thapa

Wayne State University Dissertations

ABSTRACT

A STUDY OF STRUCTURE-PROPERTY CORRELATION IN V2O5 AND TiO2 BASED THIN FILMS AS FUNCTIONAL MATERIALS

by

CHANDRA THAPA

June 2010

Advisor: Dr. Ratna Naik

Co-Advisor: Dr. K. R. Padmanabhan

Major: Physics (Condensed Matter)

Degree: Doctor of Philosophy

The focus of this thesis is to study the structure-property correlation in thin films of V2O5 and TiO2 based transition metal oxides as functional materials. V2O5 is investigated as a cathode material for lithium ion battery and TiO2 as a high-K dielectric material.

We studied V2O5 thin films prepared by spin coating using three different types of precursors, MOD precursor, sol-gel organic ...


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