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Full-Text Articles in Physical Sciences and Mathematics

Physics 2710 – Example Exam I, David Peak Sep 2013

Physics 2710 – Example Exam I, David Peak

Exams

No abstract provided.


Diverse Electron-Induced Optical Emissions From Space Observatory Materials At Low Temperatures, Jr Dennison, Amberly Evans Jensen, Gregory Wilson, Justin Dekany, Charles W. Bowers, Robert H. Meloy Sep 2013

Diverse Electron-Induced Optical Emissions From Space Observatory Materials At Low Temperatures, Jr Dennison, Amberly Evans Jensen, Gregory Wilson, Justin Dekany, Charles W. Bowers, Robert H. Meloy

Conference Proceedings

Electron irradiation experiments have investigated the diverse electron-induced optical and electrical signatures observed in ground-based tests of various space observatory materials at low temperature. Three types of light emission were observed: (i); long-duration cathodoluminescence which persisted as long as the electron beam was on (ii) short-duration (<1 s) arcing, resulting from electrostatic discharge; and (iii) intermediate-duration (~100 s) glow—termed “flares”. We discuss how the electron currents and arcing—as well as light emission absolute intensity and frequency—depend on electron beam energy, power, and flux and the temperature and thickness of different bulk (polyimides, epoxy resins, and silica glasses) and composite dielectric materials (disordered SiO2 thin films, carbon- and fiberglass-epoxy composites, and macroscopically-conductive carbon-loaded polyimides). We conclude that electron-induced optical emissions resulting from interactions between observatory materials and the space environment electron flux can, in specific circumstances, make significant contributions to the stray light background that could possibly adversely affect the performance of space-based observatories.


Pulsed Electro-Acoustic (Pea) Measurements Of Embedded Charge Distributions, Jr Dennison, Lee H. Pearson Sep 2013

Pulsed Electro-Acoustic (Pea) Measurements Of Embedded Charge Distributions, Jr Dennison, Lee H. Pearson

Conference Proceedings

Knowledge of the spatial distribution and evolution of embedded charge in thin dielectric materials has important applications in semiconductor, high-power electronic device, high-voltage DC power cable insulation, high-energy and plasma physics apparatus, and spacecraft industries. Knowing how, where, and how much charge accumulates and how it redistributes and dissipates can predict destructive charging effects. Pulsed Electro-acoustic (PEA) measurements— and two closely related methods, Pressure Wave Propagation (PWP) and Laser Intensity Modulation (LIMM)— nondestructively probe such internal charge distributions. We review the instrumentation, methods, theory and signal processing of simple PEA experiments, as well as the related PPW and LIMM methods. …


Phanerozoic Surface History Of The Slavecraton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring Sep 2013

Phanerozoic Surface History Of The Slavecraton, Alexis K. Ault, Rebecca M. Flowers, Samuel A. Bowring

Geosciences Faculty Publications

New apatite (U-Th)/He (AHe) thermochronometry data and key geologic constraints from Slave craton kimberlites are used to develop a model for the Phanerozoic burial, unroofing, and hypsometric history of the northwestern Canadian shield. AHe dates range from 210 ± 13 to 382 ± 79 Ma, are older in the eastern Slave craton and decrease westward, and resolve the spatial extent, thickness, and history of now-denuded sedimentary units. Results indicate Paleozoic heating to temperatures ≥85–90°C, suggesting regional burial beneath ≥2.8 km of strata while the region was at sea level, followed by the westward migration of unroofing across the craton. This …


Inverse Method For Simultaneous Determination Of Soil Water Flux Density And Thermal Properties With A Penta-Needle Heat Pulse Probe, Changbing Yang, Masaru Sakai, Scott B. Jones Sep 2013

Inverse Method For Simultaneous Determination Of Soil Water Flux Density And Thermal Properties With A Penta-Needle Heat Pulse Probe, Changbing Yang, Masaru Sakai, Scott B. Jones

Plants, Soils, and Climate Faculty Publications

An accurate method for determination of in situ soil water flux density continues to be the most sought after and yet elusive hydrologic measurement. The penta-needle heat pulse probe (PHPP) employs a central heater needle surrounded by an orthogonal arrangement of four thermistor needles for two-component water flux density estimation. An analytical solution and inverse fitting method are presented for simultaneous estimation of thermal properties and soil water flux density using PHPP measurements. The approach yields estimates of both components of the flux in a plane normal to the axis of the PHPP needles. The method was evaluated using data …


Paleoseismology Of The Southern Panamint Valley Fault: Implications For Regional Earthquake Occurrence And Seismic Hazard In Southern California, Lee J. Mcauliffe, James F. Dolan, Eric Kirby, Chris Rollins, Ben Haravitch, Steve Alm, Tammy M. Rittenour Sep 2013

Paleoseismology Of The Southern Panamint Valley Fault: Implications For Regional Earthquake Occurrence And Seismic Hazard In Southern California, Lee J. Mcauliffe, James F. Dolan, Eric Kirby, Chris Rollins, Ben Haravitch, Steve Alm, Tammy M. Rittenour

Geosciences Faculty Publications

[1] Paleoseismologic data from the southern Panamint Valley fault (PVF) reveal evidence of at least four surface ruptures during late Holocene time (0.33–0.48 ka, 0.9–3.0 ka, 3.3–3.6 ka, and >4.1 ka). These paleo‐earthquake ages indicate that the southern PVF has ruptured at least once and possibly twice during the ongoing (≤1.5 ka) seismic cluster in the Mojave section of the eastern California shear zone (ECSZ). The most recent event (MRE) on the PVF is also similar in age to the 1872 Owens Valley earthquake and the geomorphically youthful MRE on the Death Valley fault. The timing of the three oldest …


Membrane Lipid-Modulated Mechanism Of Action And Non-Cytotoxicity Of Novel Fungicide Aminoglycoside Fg08, Sanjib Shrestha, Michelle Grilley, Marina Y. Fosso, Cheng-Wei Tom Chang, Jon Y. Takemoto Sep 2013

Membrane Lipid-Modulated Mechanism Of Action And Non-Cytotoxicity Of Novel Fungicide Aminoglycoside Fg08, Sanjib Shrestha, Michelle Grilley, Marina Y. Fosso, Cheng-Wei Tom Chang, Jon Y. Takemoto

Chemistry and Biochemistry Faculty Publications

A novel aminoglycoside, FG08, that differs from kanamycin B only by a C8 alkyl chain at the 4″-O position, was previously reported. Unlike kanamycin B, FG08 shows broad-spectrum fungicidal but not anti-bacterial activities. To understand its specificity for fungi, the mechanism of action of FG08 was studied using intact cells of the yeast Saccharomyces cerevisiae and small unilamellar membrane vesicles. With exposure to FG08 (30 µg mL−1), 8-fold more cells were stained with fluorescein isothiocyanate, cells had 4 to 6-fold higher K+ efflux rates, and 18-fold more cells were stained with SYTOX Green in comparison to exposure to kanamycin B …


Rayleigh Lidar Observations Of The Mid-Latitude Mesosphere During Stratospheric Warming Events And A New Rayleigh-Mie-Raman Lidar At Usu, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron, Matthew T. Emerick Sep 2013

Rayleigh Lidar Observations Of The Mid-Latitude Mesosphere During Stratospheric Warming Events And A New Rayleigh-Mie-Raman Lidar At Usu, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron, Matthew T. Emerick

Presentations

No abstract provided.


Improving Resilience In Mixed Farming Systems To Pending Climate Change In Far Western Nepal, D. Layne Coppock Sep 2013

Improving Resilience In Mixed Farming Systems To Pending Climate Change In Far Western Nepal, D. Layne Coppock

Environment and Society Faculty Publications

Participatory Rural Appraisal (PRA) exercises were conducted in four cluster-VDCs in Bajura district, Far Western Nepal from May 19 to June 8, 2013. These exercises were undertaken to gain a better understanding of community resources and to identify opportunities that will assist these rural farming communities to cope with and adapt to climate change. Ten key tools were applied during the PRA exercise in each community cluster: Social Resource Map, Transect Walks, Farm Sketches, Disadvantaged Group mapping, Historical Community Timelines, Gender Daily Calendar, Seasonal Farming Calendars, Institutional/Stakeholders Analysis (Venn Diagrams) and Focused Group Discussion.


Discrete Dynamics On Noncommunative Cw Complexs, Vida Milani, Seyed M.H. Mansourbeigi Sep 2013

Discrete Dynamics On Noncommunative Cw Complexs, Vida Milani, Seyed M.H. Mansourbeigi

Computer Science Student Research

The concept of discrete multivalued dynamical systems for noncommutative CW complexes is developed. Stable and unstable manifolds are introduced and their role in geometric and topological configurations of noncommutative CW complexes is studied. Our technique is illustrated by an example on the noncommutative CW complex decomposition of the algebra of continuous functions on two dimensional torus.


Mesospheric Density Climatologies Determined At Midlatitudes Using Rayleigh Lidar, David L. Barton, Vincent B. Wickwar, Leda Sox, Joshua P. Herron Aug 2013

Mesospheric Density Climatologies Determined At Midlatitudes Using Rayleigh Lidar, David L. Barton, Vincent B. Wickwar, Leda Sox, Joshua P. Herron

Posters

The original Rayleigh-scatter lidar that operated at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W) in the Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU), collected 11 years of data between 1993 and 2004. From Rayleigh lidar photon-count returns, relative densities throughout the mesosphere, from 45 to 90 km, were determined. Using these relative densities, three climatologies are derived, each using a different density normalization method at 45 km: the first method normalized the relative densities to a constant; the second normalized them to the NRLMSISe00 empirical model; and the third normalized them to …


Multi-Year Observations Of Mid-Latitude Middle Atmospheric Winds, Waves, And Temperature Associated With Ssw Events Over Northern Utah, Chad Fish, Vincent B. Wickwar, B. Thurairajah, Jan J. Sojka, F. T. Berkey, S. Bailey, Titus Yuan, Michael J. Taylor, N. Mitchell, W. Hocking Aug 2013

Multi-Year Observations Of Mid-Latitude Middle Atmospheric Winds, Waves, And Temperature Associated With Ssw Events Over Northern Utah, Chad Fish, Vincent B. Wickwar, B. Thurairajah, Jan J. Sojka, F. T. Berkey, S. Bailey, Titus Yuan, Michael J. Taylor, N. Mitchell, W. Hocking

Presentations

We investigate the behavior of 14 years of wind, wave, and temperature observations in the middle atmosphere over northeastern Utah, USA during periods of sudden stratospheric warming events. This systematic review of the impacts of sudden stratospheric warming events on the middle atmosphere at a northern mid-latitude site is conducted using ground based measurements from imaging Doppler interferometry and meteor wind radar and Na and Raleigh lidar and space based measurements made by the Sounding of the Atmosphere Using Broadband Emission Radiometry sensor onboard the NASA sponsored Thermosphere Ionosphere mesosphere Energetics Dynamics Mission.


The Mid-Latitude Mesosphere’S Response To Sudden Stratospheric Warmings As Determined From Rayleigh Lidar Temperatures, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron Aug 2013

The Mid-Latitude Mesosphere’S Response To Sudden Stratospheric Warmings As Determined From Rayleigh Lidar Temperatures, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron

Presentations

The original Rayleigh-scatter lidar that operated at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W) in the Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU), collected temperature data for 11 years, from 1993 through 2004. The temperatures derived from these data extended over the mesosphere, from 45 to 90 km. Recently, they were combined with other observations to examine the mid-latitude responses to Sudden Stratospheric Warmings (SSWs) in the polar regions. (The other observational instruments being an ionosonde, a meteor wind radar, a Na lidar, and a satellite.) Extensive Rayleigh lidar observations were made …


Midlatitude, Rayleigh-Mie-Raman Lidar For Observations From 15 To 120 Km, Vincent B. Wickwar, Leda Sox, Joshua P. Herron, Matthew T. Emerick Aug 2013

Midlatitude, Rayleigh-Mie-Raman Lidar For Observations From 15 To 120 Km, Vincent B. Wickwar, Leda Sox, Joshua P. Herron, Matthew T. Emerick

Presentations

No abstract provided.


Diverse Electron-Induced Optical Emissions From Space Observatory Materials At Low Temperatures, Jr Dennison, Amberly Evans Jensen, Greg Wilson, Justin Dekany, Charles W. Bowers, Robert Meloy Aug 2013

Diverse Electron-Induced Optical Emissions From Space Observatory Materials At Low Temperatures, Jr Dennison, Amberly Evans Jensen, Greg Wilson, Justin Dekany, Charles W. Bowers, Robert Meloy

Presentations

No abstract provided.


Pulse Electro-Acoustic (Pea) Measurements Of Embedded Charge Distributions, Jr Dennison, Lee H. Pearson Aug 2013

Pulse Electro-Acoustic (Pea) Measurements Of Embedded Charge Distributions, Jr Dennison, Lee H. Pearson

Presentations

No abstract provided.


Consequences Of Cathodoluminescence For Cryogenic Applications Of Sio2-Based Space Observatory Optics And Coatings, Amberly Evans, Jr Dennison, Greg Wilson, Justin Dekany, Charles W. Bowers, Robert H. Meloy, James Heaney Aug 2013

Consequences Of Cathodoluminescence For Cryogenic Applications Of Sio2-Based Space Observatory Optics And Coatings, Amberly Evans, Jr Dennison, Greg Wilson, Justin Dekany, Charles W. Bowers, Robert H. Meloy, James Heaney

Presentations

No abstract provided.


Modeling The Ionospheric E And F1 Regions: Using Sdo-Eve Observations As The Solar Irradiance Driver, Jan Josef Sojka, Joseph B. Jensen, Michael David, Robert W. Schunk, Tom Woods, Frank Eparvier Aug 2013

Modeling The Ionospheric E And F1 Regions: Using Sdo-Eve Observations As The Solar Irradiance Driver, Jan Josef Sojka, Joseph B. Jensen, Michael David, Robert W. Schunk, Tom Woods, Frank Eparvier

All Physics Faculty Publications

Over the altitude range of 90–150 km, in dayside nonauroral regions, ionization is controlled almost entirely by solar ultraviolet irradiance; the response time for ionization during solar exposure is almost instantaneous, and likewise, the time scale for recombination into neutral species is very fast when the photoionizing source is removed. Therefore, if high-resolution solar spectral data are available, along with accurate ionization cross sections as a function of wavelength, it should be possible to model this ionospheric region with greater accuracy. The Extreme Ultraviolet Variability Experiment (EVE) instrument on the National Aeronautics and Space Administration Solar Dynamics Observatory (SDO) satellite, …


Understanding Light Pollution In And Around Tucson, Arizona, Rachel K. Nydegger Aug 2013

Understanding Light Pollution In And Around Tucson, Arizona, Rachel K. Nydegger

Browse All Undergraduate research

No abstract provided.


Two Scenes From Utah's Stratigraphic Record: Neoproterozoic Snowball Earth, Before And After, Dawn Schmidli Hayes Aug 2013

Two Scenes From Utah's Stratigraphic Record: Neoproterozoic Snowball Earth, Before And After, Dawn Schmidli Hayes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research is focused on rock units deposited in northern Utah before and after global glacial events of unprecedented magnitude, commonly referred to as
“Snowball Earth” glaciations. The rock units deposited prior to the beginning of these glaciations (~770 to 740 million years ago) include the Uinta Mountain Group in Utah’s Uinta Mountains. Rock units deposited after the glaciations (either ~665 or ~635 million years ago) include parts of the Kelley Canyon Formation on Antelope Island in the Great Salt Lake. These rocks, deposited in shallow ocean environments, record the history of life and ocean chemistry just before and after …


Formation, Deformation, And Incision Of Colorado River Terraces Upstream Of Moab, Utah, Andrew P. Jochems Aug 2013

Formation, Deformation, And Incision Of Colorado River Terraces Upstream Of Moab, Utah, Andrew P. Jochems

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The history of rivers is laid down as sediment in all landscapes, typically as a function of climate, geologic structures, and/or changes in sea level. When a river abandons its floodplain, this sediment collectively constitutes a landform called a fluvial terrace. Terraces are used to unlock prior characteristics of a river flowing through a given area at both local and regional scales. Dating terrace sediment allows comparison to known changes in climate and geologic deformation, two significant controls on the hydraulics of rivers and the deposition of their sediment loads.

The importance of terraces lies in their utility as markers …


Mechanisms Of Vegetation-Induced Channel Narrowing On An Unregulated Canyon-Bound River, Rebecca Blanche Manners Aug 2013

Mechanisms Of Vegetation-Induced Channel Narrowing On An Unregulated Canyon-Bound River, Rebecca Blanche Manners

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The accurate prediction of river channel width remains a fundamental area of investigation in the field of geomorphology. River managers and scientists are interested in understanding how a channel will respond to environmental perturbations such as altered runoff patterns from climate change, a new dam, or a pulse of sediment from a landslide. Increasingly, studies that focus on this question acknowledge the importance of accounting for the vegetation that lines the river banks. For this dissertation, I strove to identify some of the primary ways by which vegetation affects channel width.

At a fundamental level, vegetation influences the size of …


Modeling Habitat Use Of A Fringe Greater Sage-Grouse Population At Multiple Spatial Scales, Anya Cheyenne Burnett Aug 2013

Modeling Habitat Use Of A Fringe Greater Sage-Grouse Population At Multiple Spatial Scales, Anya Cheyenne Burnett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) are a prominent bird species of sagebrush-dominated landscapes across the western United States. Over the past 15 years, sage-grouse have gained international attention due to decreasing population trends despite management efforts. In 2010 the U.S. Fish and Wildlife Service designated this species as warranted for listing under the Endangered Species Act, but the listing was precluded by other species at higher conservation risk. Habitat loss, degradation, and fragmentation have been implicated as primary sources of declines in sage-grouse distribution and abundance. The Bald Hills population in southwestern Utah occupies an area with …


Studying Light Pollution In And Around Tucson, Az, Rachel K. Nydegger Aug 2013

Studying Light Pollution In And Around Tucson, Az, Rachel K. Nydegger

Physics Capstone Projects

Eight housed data logging Sky Quality Meters (SQMs) are being used to gather light pollution data in southern Arizona: one at the National Optical Astronomy Observatory (NOAO) in Tucson, four located at cardinal points at the outskirts of the city, and three situated on surrounding mountain tops. To examine specifically the effect of artificial lights, the data are reduced to exclude four natural contributors to lighting the night sky, namely, the sun, the moon, and the Milky Way. Faulty data (i.e., when certain parameters were met) were also excluded. Data were subsequently analyzed by a recently developed night sky brightness …


Gr 20 Workshop, Warsaw, July 2013, Ian M. Anderson, Charles G. Torre Aug 2013

Gr 20 Workshop, Warsaw, July 2013, Ian M. Anderson, Charles G. Torre

Presentations

These are the Maple worksheets used at the Differential Geometry in Maple Workshop, which was held at the 20th International Conference on General Relativity and Gravitation, in Warsaw, July 2013.

There are 6 worksheets which can be downloaded from the list of files below.


Schematics Of A Water Balloon Launcher Design And Reproducible Water-Balloon-Filling Procedures Used For A Middle School Summer Science Camp, Mike A. Christiansen, Boyd F. Edwards, David D. Sam Jul 2013

Schematics Of A Water Balloon Launcher Design And Reproducible Water-Balloon-Filling Procedures Used For A Middle School Summer Science Camp, Mike A. Christiansen, Boyd F. Edwards, David D. Sam

USU Uintah Basin Faculty Publications

We recently held a Science Summer Camp for middle school students, designed to infuse young people with increased excitement for STEM (Science, Technology, Engineering, and Math) subjects. Our efforts, which received nationally-syndicated news coverage, included the invention of a versatile water balloon launcher.

This document contains:

(1) detailed construction schematics and user operation guidelines for our balloon launcher;

(2) data and instructions for reproducibly filling water balloons to specific volumes and weights, within used by students during the summer camp.


Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni Jul 2013

Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


The Spacetime Geometry Of A Null Electromagnetic Field, Charles G. Torre Jul 2013

The Spacetime Geometry Of A Null Electromagnetic Field, Charles G. Torre

Presentations and Publications

We give a set of local geometric conditions on a spacetime metric which are necessary and sufficient for it to be a null electrovacuum, that is, the metric is part of a solution to the Einstein-Maxwell equations with a null electromagnetic field. These conditions are restrictions on a null congruence canonically constructed from the spacetime metric, and can involve up to five derivatives of the metric. The null electrovacuum conditions are counterparts of the Rainich conditions, which geometrically characterize non-null electrovacua. Given a spacetime satisfying the conditions for a null electrovacuum, a straightforward procedure builds the null electromagnetic field from …


An Electrolysis Experiment For A Middle School Summer Science Camp, Mike A. Christiansen, Leslie Jessup, Kevin D. Woodward Jul 2013

An Electrolysis Experiment For A Middle School Summer Science Camp, Mike A. Christiansen, Leslie Jessup, Kevin D. Woodward

Chemistry and Biochemistry Faculty Publications

Higher education is often culturally deemphasized in the geographic area served by our rural, regional campus. As a result, faculty members have the opportunity to spearhead teaching efforts designed to educate the community about the importance of obtaining a post-secondary degree. To this end, we recently held a Science Summer Camp for middle school students, designed to infuse young people with an increased excitement for STEM (Science, Technology, Engineering, and Math) education. In this report, we summarize a chemical electrolysis experiment we carried out with middle school students for our annual Science Summer Camp. We also provided procedural guidelines for …


The Correlation Between Radiation Induced Conductivity (Ric) And Electron Beam Induced Luminescence In Disordered Sio2, Ryan Carl Hoffmann, Jr Dennison, Greg Wilson, Amberly Evans Jensen Jun 2013

The Correlation Between Radiation Induced Conductivity (Ric) And Electron Beam Induced Luminescence In Disordered Sio2, Ryan Carl Hoffmann, Jr Dennison, Greg Wilson, Amberly Evans Jensen

Presentations

No abstract provided.