Physical Sciences and Mathematics Commons^™

High-Frequency Pulsed-Electro-Acoustic (Pea) Measurements For Mapping Charge Distribution, Kristina Sorensen, Lee H. Pearson, Jr Dennison, Timothy E. Doyle, Kent D. Hartley

Presentations

No abstract provided.

Power And Charge Deposition In Multilayer Dielectrics Undergoing Monoenergetic Electron Bombardment, Gregory Wilson, Jr Dennison, Amberly Evans, Justin Dekany

Presentations

No abstract provided.

Short Period Gravity Waves In The Arctic Atmosphere Over Alaska, Michael Negale, Kim Nielsen, Michael J. Taylor, Britta Irving, Richard Collins

Physics Student Research

The propagation nature and sources of short-period gravity waves have been studied extensively at low and mid-latitudes, while their extent and nature at the polar regions are less known. During the last decade, observations from select sites on the Antarctic continent have revealed a significant presence of these waves over the southern Polar Region as well as shown unexpected dynamical behavior. In contrast, observations over the Arctic region are few and the dynamical behavior is unknown. A recent project was initiated in January 2011 to investigate the presence and dynamics of these waves over interior Alaska. This site provides an …

Space Impact Ejecta Model Of Micrometeoroid Collision On Misse-6, Kelby Peterson, Jr Dennison

Presentations

No abstract provided.

Power And Charge Deposition In Multilayer Dielectrics Undergoing Monoenergetic Electron Bombardment, Gregory Wilson, Jr Dennison, Amberly Evans Jensen, Justin Dekany

Presentations

No abstract provided.

Electrostatic Discharge Properties Of Fused Silica Coatings, Allen Andersen, Charles Sim, Jr Dennison

Graduate Student Posters

The electric field value at which electrostatic discharge (ESD) occurs was studied for thin coatings of fused silica (highly disordered SiO2/SiOx) on conductive substrates, such as those encountered as optical coatings and in Si microfabrication. The electrostatic breakdown field was determined using an increasing voltage, while monitoring the leakage current. A simple parallel-plate capacitor geometry was used, under medium vacuum and at temperatures down to ~150 K using a liquid N2 reservoir. The breakdown field, pre-breakdown arcing and I-V curves for fused silica samples are compared for ~60 nm and ~80 μm thick, room and low temperature, and untreated and …

Velocity Plateaus In Traveling-Wave Electrophoresis, R. Correll, Boyd F. Edwards

All Physics Faculty Publications

One-dimensional models are used to study traveling-wave electrophoresis, a tunable method for separating charged analytes. A traveling-electrode model reveals the mechanism for longitudinal oscillations. A stationary-electrode model explains the origin of mode-locked plateaus in the average velocity, predicts devil's staircases with nested Farey sequences, and reduces to a continuum sinusoidal model in the high electrode-density limit. © 2012 American Physical Society.

The Rise Of Science In Japan: 日本科学発展と原因, Mario Harper

Browse All Undergraduate research

日本の科学は第二次世界大戦から始まったと多くの人は思っている。もちろん、多くの発展は戦後に行われたのは事実。しかし、戦争以前にも「テクノロジージャパン」な考え方が非常に寿実していた。このスライドショーは日本科学発展の原因となることをいくつか見ています。

Histological Analysis Of Biological Tissues Using High-Frequency Ultrasound, Kristina Sorensen, Timothy Doyle, Brett D. Boret, Monica Cervantes, J. Andrew Chappell, Bradley J. Curtis, Matthew A. Grover, Janeese E. Stiles, Laurel A. Thompson

Browse All Undergraduate research

No abstract provided.

Electron Beam Induced Luminescence Of Sio2 Optical Coatings, John R. Dennison, Amberly Evans, Gregory Wilson, Charles W. Bowers, Robert Meloy

All Physics Faculty Presentations

Optical coatings of disordered thin film SiO2/SiOx dielectric samples on reflective metal substrates exhibited cathodoluminescence under electron beam irradiation. Measurements of the absolute radiance and emission spectra as functions of incident electron energy, flux and power over a range of sample temperatures are reported. Radiance reached a saturation plateau at high incident electron power. Well below saturation radiance scaled with deposited power, that is linearly with incident power for lower-energy non-penetrating electrons and decreasing with increasing energy for penetrating radiation. Four bands were observed in spectral measurements from 300 nm to 1000 nm. Changes in peak intensity and shifts in …

How To Create A Two-Component Spinor, Charles G. Torre

How to... in 10 minutes or less

Let (M, g) be a spacetime, i.e., a 4-dimensional manifold M and Lorentz signature metric g. The key ingredients needed for constructing spinor fields on the spacetime are: a complex vector bundle E -> M ; an orthonormal frame on TM ; and a solder form relating sections of E to sections of TM (and tensor products thereof). We show how to create a two-component spinor field on the Schwarzschild spacetime using the DifferentialGeometry package in Maple. PDF and Maple worksheets can be downloaded from the links below.

Electron Induced Charging And Arcing Of Multilayered Dielectric Materials, John R. Dennison, Gregory Wilson, Amberly Evans

All Physics Faculty Presentations

Measurements of the charge distribution in electron-bombarded, thin-film, multilayered dielectric samples showed that charging of multilayered materials evolves with time and is highly dependent on incident energy; this is driven by electron penetration depth, electron emission and material conductivity. Based on the net surface potential’s dependence on beam current, electron range, electron emission and conductivity, measurements of the surface potential, displacement current and beam energy allow the charge distribution to be inferred. To take these measurements, a thin-film disordered SiO2 structure with a conductive middle layer was charged using 200 eV and 5 keV electron beams with regular 15 s …

Bottom Canyon Hazardous Fuel Reduction Phase Ii, United States Department Of The Interior, Bureau Of Land Management

Environmental Assessments (UT)

The purpose of the Bottom Canyon Hazardous Fuel Reduction Phase II project is to reduce the buildup of hazardous fuels that have accumulated over the last several decades in order to prevent the potential for large catastrophic fire events. In addition, the proposed action is needed to maintain important sage-steppe habitat for a variety of wildlife species in the project area.

Gasco Production Company Proposes To Drill 6 Oil Wells From 6 Existing Well Pads, United States Department Of The Interior, Bureau Of Land Management

Environmental Assessments (UT)

This Environmental Assessment (EA) has been prepared to analyze the potential impacts of GASCO Production Company (GASCO) oil well drilling project in the 8 Mile Flat area of Uintah County, Utah. GASCO has a valid existing right to extract mineral resources from federal leases UTU-16544, UTU-76262, UTU-75090 & UTU-78433 subject to the lease's terms and conditions. The BLM oil and gas leasing program encourages development of domestic oil and gas reserves and the reduction of U.S. dependence on foreign energy sources.

Moonshine Ridge Hazardous Fuel Reduction Phase Ii, United States Department Of The Interior, Bureau Of Land Management

Environmental Assessments (UT)

The purpose of the Moonshine Ridge Hazardous Fuel Reduction Phase II project is to reduce the buildup of hazardous fuels that have accumulated over the last several decades in order to prevent the potential for large catastrophic fire events. In addition, the proposed action is needed to maintain important sage-steppe habitat for a variety of wildlife species in the project area.

Ultrasonic Analysis Of Breast Tissue For Pathology Classification, Kristina Marie Sorensen

Undergraduate Honors Capstone Projects

Real time measurements may assist surgeons in obtaining negative or cancer free margins during lumpectomy to eliminate invasive re-excision. Previous findings show that high-frequency ultrasound can differentiate between a range of breast pathologies in surgical specimens. Two parameters, peak density and second-order spectral slope, are sensitive to histopathology. Our objective was to determine the mechanism linking high-frequency ultrasound to histology. The hypothesis is that ultrasound sensitivity is a function of the microscopic heterogeneity (and thus histology) of the tissue. Ultrasonic results from breast specimens were used to construct a multivariate analysis of the parameters that permitted differentiation of normal, adipose, …

Cedar Electrodynamics Thermosphere Ionosphere (Eti) Challenge For Systematic Assessment Of Ionosphere/Thermosphere Models: Electron Density, Neutral Density, Nmf2, And Hmf2 Using Space Based Observations, J. S. Shim, M. Kuznetsova, L. Rastätter, D. Bilitza, L. Butala, M. Emery, B. Foster, T. J. Fuller-Rowell, J. Huba, A. J. Mannucci, X. Pi, A. Ridley, Ludger Scherliess, Jan Josef Sojka, P. Stephens, D. C. Thompson, D. Weimer, Lie Zhu, E. Sutton

All Physics Faculty Publications

In an effort to quantitatively assess the current capabilities of Ionosphere/Thermosphere (IT) models, an IT model validation study using metrics was performed. This study is a main part of the CEDAR Electrodynamics Thermosphere Ionosphere (ETI) Challenge, which was initiated at the CEDAR workshop in 2009 to better comprehend strengths and weaknesses of models in predicting the IT system, and to trace improvements in ionospheric/thermospheric specification and forecast. For the challenge, two strong geomagnetic storms, four moderate storms, and three quiet time intervals were selected. For the selected events, we obtained four scores (i.e., RMS error, prediction efficiency, ratio of the …

Electron Beam Induced Luminescence Of Sio2 Optical Coatings, John R. Dennison, Amberly Evans, Gregory Wilson, Charles W. Bowers, Robert Meloy

All Physics Faculty Publications

Optical coatings of disordered thin film SiO2/SiOx dielectric samples on reflective metal substrates exhibited cathodoluminescence under electron beam irradiation. Measurements of the absolute radiance and emission spectra as functions of incident electron energy, flux and power over a range of sample temperatures are reported. Radiance reached a saturation plateau at high incident electron power. Well below saturation radiance scaled with deposited power, that is linearly with incident power for lower-energy non-penetrating electrons and decreasing with increasing energy for penetrating radiation. Four bands were observed in spectral measurements from 300 nm to 1000 nm. Changes in peak intensity and shifts in …

The Octonions And The Exceptional Lie Algebra G2, Ian M. Anderson

Research Vignettes

The octonions O are an 8-dimensional non-commutative, non-associative normed real algebra. The set of all derivations of O form a real Lie algebra. It is remarkable fact, first proved by E. Cartan in 1908, that the the derivation algebra of O is the compact form of the exceptional Lie algebra G2. In this worksheet we shall verify this result of Cartan and also show that the derivation algebra of the split octonions is the split real form of G2.

PDF and Maple worksheets can be downloaded from the links below.

A Novel Analytical Solution To Steady-State Evaporation From Soil And Film Region Thickness, Morteza Sadeghi, Nima Shokri, Scott B. Jones

Plants, Soils, and Climate Faculty Publications

Evaporation from soil and other porous media constitutes a significant source of water loss affecting global water balance and energy exchange between land and atmosphere. The presence of a shallow water table can lead to sustained water loss that is dependent on porous media hydraulic properties and water table depth among other factors. In this paper, an exact analytical solution to steady state evaporation from porous media is developed using the Brooks-Corey hydraulic conductivity model. The solution is presented in terms of a set of infinite series. An advantage of this solution compared to previous derivations is that the infinite …

The Local Food Movement: Definitions, Benefits, And Resources, Roslynn Brain

Environment and Society Faculty Publications

What does it mean to eat locally? Although perceptions of what makes up “local food” differ by region (due in large part to varying climates, soil types, and populations), most researchers accept that eating locally means minimizing the distance between production and consumption, especially in relation to the modern mainstream food system (Peters et al., 2008). According to the 2008 Farm Act, a product can be marketed as locally or regionally produced if its end-point purchase is within 400 miles from its origin, or within state boundaries (Martinez et al., 2010). Most retailers, however, consider local to be on a …

Higher Order Symmetries Of The Kdv Equation, Ian M. Anderson

Research Vignettes

In this worksheet we symbolically construct the formal inverse of the total derivative operator and use it to construct the recursion operator for the higher-order symmetries of the KdV equation. Using this recursion operator we generate the first 5 generalized symmetries of the KdV equation and verify that they all commute.

PDF and Maple worksheets can be downloaded from the links below.

An Embedded-Atom-Method Model For Alkali-Metal Vibrations, D. Mark Riffe, Richard B. Wilson

All Physics Faculty Publications

We present an embedded-atom-method (EAM) model that accurately describes vibrational dynamics in the alkali metals Li, Na, K, Rb, and Cs. Bulk dispersion curves, frequency-moment Debye temperatures, and temperature-dependent entropy Debye temperatures are all in excellent agreement with experimental results. The model is also well suited for studying surface vibrational dynamics in these materials, as illustrated by calculations for the Na(110) surface.

Testing A Pyroclimatic Hypothesis On The Mexico-United States Border, Peter Z. Fule, Larissa L. Yocom Kent, Citlali Cortes Montano, Donald A. Falk, Julian Cerano, Jose Villanueva-Diaz

Wildland Resources Faculty Publications

The “pyroclimatic hypothesis” proposed by F. Biondi and colleagues provides a basis for testable expectations about climatic and other controls of fire regimes. This hypothesis asserts an a priori relationship between the occurrence of widespread fire and values of a relevant climatic index. Such a hypothesis provides the basis for predicting spatial and temporal patterns of fire occurrence based on climatic control. Forests near the Mexico–United States border offer a place to test the relative influence of climatic and other controls in mountain ranges that are ecologically similar and subject to broadly similar top-down climatic influence, but with differing cultural …

A Classroom Experiment: Implementing A Math-Talk Environment In A University Setting, Janice Bodily

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A need for reform in teaching mathematics has long been recognized. The traditional classroom with the sage on the stage lacks a higher level of engagement for the students and therefore, produces a lower level of student satisfaction. The math-talk classroom is one attempt to engage students and to raise the level of interaction and discussion, thus enabling students to increase their level of comprehension. In an effort to create a math-talk experience in my Calculus II course, I applied the methodology of Thinking Through a Lesson Protocol (TTLP) to test its effectiveness in assisting the instructor in creating an …

Pine Springs Hazardous Fuel Reduction Phase Ii, United States Department Of The Interior, Bureau Of Land Management

Environmental Assessments (UT)

The purpose of the Pine Springs Hazardous Fuel Reduction Phase II project is to reduce the buildup of hazardous fuels that have accumulated over the last several decades in order to prevent the potential for large catastrophic fire events. In addition, the proposed action is needed to maintain important sage-steppe habitat for a variety of wildlife species in the project area.

A Prototype Automated Resolution Service For Public-Health Master Person Index, Sarvesh Jain

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A Master Person Index (MPI) is a software system that links together the records about individuals from a diverse set of data sources and that allows data consumers to ¬¬retrieve correlated data for a given person. The Utah Department of Health recently contracted with Utah State University to build an MPI that links data from four initial data sources, and with enough extensibility that it will eventually handle dozens. This MPI, called the Utah Public-health Master Person Index or phMPI, was to include a special software component that automatically computed the “best version of truth” about each individual using correlated …

A Mechanistic Study Of Catalytic Promiscuity In Protein Phosphatase 1, Yuan Chu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

"Catalytic promiscuous" enzymes, which possess additional activities besides their "native" activity, albeit with a lower efficiency than the main reaction, have become a new frontier for biochemistry and have received considerable attention. Catalytic promiscuity has been suggested to contribute to enzyme evolution through the mechanism of gene duplication followed by specialization of one of the two copies for the new function. Mimicking this evolutionary shortcut could also provide a more efficient route to changing the function of proteins by directed evolution.

The promiscuous phosphatase PP1 is a member of the phosphoprotein phosphatase (PPP) gene family, which is critical for the …

The Chemical Evolution Of Oceanic And Continental Lithosphere: Case Studies In The Us Cordillera, Marlon Mauricio Jean

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Among the terrestrial planets, only Earth has volcanism and plutonism that is related to plate tectonics. At the bottom of the oceans, mid-ocean ridges form where tectonic plates drift apart. More visible, and explosively dangerous, is volcanism related to the subduction of oceanic plates back into the Earth’s mantle. Less clear is the origin of the third major type of volcanism, the so-called intra-plate volcanism, which is thought to represent thermally driven upwellings from the lower mantle. This dissertation investigates two of these unique volcano-tectonic settings which occur in the western United States.

Subduction zones are regions of intense earthquake …

The Effect Of Growth Parameters On The Height And Density Of Carbon Nanotube Forests, Robert Welch Call

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rolled-up graphene sheets, known as carbon nanotubes, are grown in vertically aligned arrays called carbon nanotube forests (CNTFs). CNTFs make extremely dark surfaces. They are being investigated for use on space crafts as calibration surfaces and to protect optical sensors from unwanted signals. These CNTFs are grown by injecting a precursor consisting of a metal catalyst particle and a hydrocarbon component into a furnace at high temperature (~700°C). This study investigates the influence of several different growth parameters on the final height and density of the CNTF. Height and density influence the absorbance of the surface at different wavelengths.