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2011

Utah State University

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Articles 1 - 30 of 158

Full-Text Articles in Physical Sciences and Mathematics

A New Mass Spectrometer For Upper Atmospheric Measurements In The Auroral Region, Addison E. Everett, James S. Dyer, Mike Watson, Wayne Sanderson, Scott Schicker, Dalon Work, Christopher J. Mertens, Scott M. Bailey, Erik A. Syrstad Dec 2011

A New Mass Spectrometer For Upper Atmospheric Measurements In The Auroral Region, Addison E. Everett, James S. Dyer, Mike Watson, Wayne Sanderson, Scott Schicker, Dalon Work, Christopher J. Mertens, Scott M. Bailey, Erik A. Syrstad

Graduate Student Posters

We have previously presented a new rocket-borne time-of-flight mass spectrometer (TOF-MS) for measurements in the mesosphere / lower thermosphere (MLT). Traditionally, mass spectrometry in the MLT has been difficult, mainly due to the elevated ambient pressures of the MLT and high speeds of a sounding rocket flight, which affect the direct sampling of the ambient atmosphere and spatial resolution. The TOF-MS is a versatile, inherently adaptable, axial-sampling instrument, capable of operating in a traditional TOF mode or in a multiplexing Hadamard-transform mode where high spatial resolution is desired. To minimize bow shock effects at low altitudes (~70-110km), the ram surface …


Observations Of The Vertical Ion Drift In The Equatorial Ionosphere During The Solar Minimum Period Of 2009, R. A. Stoneback, R. A. Heelis, A. G. Burrell, W. R. Coley, Bela G. Fejer, E. Pacheco Dec 2011

Observations Of The Vertical Ion Drift In The Equatorial Ionosphere During The Solar Minimum Period Of 2009, R. A. Stoneback, R. A. Heelis, A. G. Burrell, W. R. Coley, Bela G. Fejer, E. Pacheco

Bela G. Fejer

[1] The extended solar minimum conditions in 2008 and 2009 presented an opportunity to investigate the ionosphere at lower solar activity levels than previously observed. The Coupled Ion Neutral Dynamics Investigation (CINDI) Ion Velocity Meter (IVM) instrument onboard the Communication/Navigation Outage Forecasting System is used to construct the median meridional (vertical) ion drifts, ion densities, and O+ concentrations during periods of low geomagnetic activity for four characteristic seasons each year spanning late 2008 to 2010. The presence of a large semidiurnal component in the ion drift variation at the equator produced significant differences from typical ionospheric conditions. Instead of upward …


Report On Advances In The Field Of Artificial Intelligence Attributed To Captcha, Craig M. Schow Dec 2011

Report On Advances In The Field Of Artificial Intelligence Attributed To Captcha, Craig M. Schow

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

A CAPTCHA is a specialized human interaction proof that exploits gaps between human and computer recognition abilities. By design, the hardness of a CAPTCHA is based on the difficulty of advancing the underlying artificial intelligence [AI] technology to a level that eliminates any exploitable gap. Due to this fact computer scientists have concluded that the widespread use of CAPTCHA would accelerate research in the underlying fields of AI eventually leading to near-­‐human capabilities in certain AI systems. Despite these predictions no attempt has been made to identify advances in AI which can be attributed to the use of CAPTCHA.

The …


Algebraic Properties Of Killing Vectors For Lorentz Metrics In Four Dimensions, Jesse W. Hicks Dec 2011

Algebraic Properties Of Killing Vectors For Lorentz Metrics In Four Dimensions, Jesse W. Hicks

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

Four-dimensional space-times with symmetry play a central role in the theory of general relativity. In 1961, in the book Einstein Spaces, A.Z. Petrov gave a complete local classification of four-dimensional space-times based upon their local isometry group, that is, their Lie algebra of Killing vector fields. In this report we discuss algebraic and geometric properties of these Lie algebras. A database of these properties has been computed for the five-dimensional Lie algebras of Killing vectors found in Petrov. As an application of our work, we present dieomorphisms between a few pairs of these Lie algebras of Killing vectors.


Enhancing Inettest By Improving The Programming Question And Group Grading, Sushil Dosi Dec 2011

Enhancing Inettest By Improving The Programming Question And Group Grading, Sushil Dosi

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

This report describes an improvement to the Utah State University iNetTest testing system. The iNetTest system allows instructors and/or students to: • Create/take tests with rich sets of question types (multiple choice, essay, true/false, computational programming question, etc.); • Monitor the test takers for cheating; • Auto-grade for many types of questions, as well as group grade for all question types; and • Send scores to students via either email or SMS. Specifically, this report discusses the design and development of an improved computational programming question for the iNetTest system. For programming questions, iNetTest allows for the use of various …


Gendered Livelihoods And The Politics Of Socio-Environmental Identity: Women’S Participation In Conservation Projects In Calakmul, Mexico, Claudia Radel Dec 2011

Gendered Livelihoods And The Politics Of Socio-Environmental Identity: Women’S Participation In Conservation Projects In Calakmul, Mexico, Claudia Radel

Environment and Society Faculty Publications

A livelihoods approach positions individuals, situated within households, as active agents within processes occurring at various scales. Environmental conservation efforts represent one such process with direct implications for local sustainable livelihoods and the gendered nature of livelihood strategies. In this article, I examine collective processes of socio-environmental identity construction as gendered sustainable livelihood strategies, articulated in and through the activities of women's agricultural organizations in communities bordering the Calakmul Biosphere Reserve in rural southern Mexico. I present group histories and visual evidence from group activities – adapted from participatory rural appraisal (PRA) methodology – to highlight two important concepts. These …


Accelerating Production Of Slow-Growing Intermountain West Native Plants By Modifying Their Microclimate, Sam A. Miller Dec 2011

Accelerating Production Of Slow-Growing Intermountain West Native Plants By Modifying Their Microclimate, Sam A. Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water shortages are a recurring problem in the western US. As much as 70% of yearly municipal water consumption may be used to irrigate urban landscapes. Significant water savings can be realized by installing low water landscapes, where turfgrass is replaced by low water trees, shrubs, grasses, and perennials. Intermountain West (IMW) native trees and shrubs are excellent candidates for low water landscaping. However, due to their slow initial growth, many native trees and shrubs are simply unavailable to consumers, as they are not cost effective for nursery growers to produce. In an effort to accelerate the yearly growth rates …


The Interrelationship Between The Bio- And Sequence Stratigraphy Of The Middle Cambrian Spence Shale Of Northern Utah And Southern Idaho, Eva Lyon Dec 2011

The Interrelationship Between The Bio- And Sequence Stratigraphy Of The Middle Cambrian Spence Shale Of Northern Utah And Southern Idaho, Eva Lyon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This project was undertaken with the objective of discerning the relationship between sea level change and changes in the fauna of the Spence Shale. A combination of field and lab work was employed to undertake this research. The Spence Shale is rich in fossils from the earliest period of visible life on this planet. It provides a unique window onto the evolution of life and changes in the Earth at this time. It is important to study this relationship between sea level and life changes as these conditions are constantly changing, particularly in this day and age. A better understanding …


Determining Co2 Storage Potential: Characterization Of Seal Integrity And Reservoir Failure In Exposed Analogs, Daniel Corey Barton Dec 2011

Determining Co2 Storage Potential: Characterization Of Seal Integrity And Reservoir Failure In Exposed Analogs, Daniel Corey Barton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sequestration of carbon dioxide (CO2) into subsurface porous sandstone is proposed as a method for reducing accumulation of anthropogenic emissions of CO2 into the atmosphere. Natural exposures of reservoir and top-seal pairs in central and southeastern Utah are identified as analogs to proposed CO2 injection targets. Reservoir and top-seal pairs in natural analog exposures are analyzed in tandem to evaluate evidence for paleo-migration of fluids and/or hydrocarbons from the reservoir through the top seal. The San Rafael Swell and Monument Uplift exhibit similar structure and exposures of Jurassic units yet differ in amount and type of …


Pedestrian Leadership And Egress Assistance Simulation Environment (Please), Kyle D. Feuz Dec 2011

Pedestrian Leadership And Egress Assistance Simulation Environment (Please), Kyle D. Feuz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pedestrian simulation models are used in many different applications including, the design of safer buildings, the validation of fire codes, and automatic video surveillance and tracking. By improving the simulation model used, each of the application areas can experience similar improvements in accuracy. Current simulation models fail to address key concerns in representing pedestrian knowledge and in accurately modeling group formation. This project has at its core the goal of bringing attention these areas of concern and providing an initial look at ways to solve these problems.

The Pedestrian Leadership and Egress Assistance Simulation Environment (PLEASE) is developed specifically to …


Potential Effects Of Altered Precipitation Regimes On Primary Production In Terrestrial Ecosystems, Joanna S. Hsu Dec 2011

Potential Effects Of Altered Precipitation Regimes On Primary Production In Terrestrial Ecosystems, Joanna S. Hsu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In addition to causing an increase in mean temperatures, climate change is also altering precipitation regimes across the globe. General circulation models project both latitude-dependent changes in precipitation mean and increases in precipitation variability. These changes in water availability will impact terrestrial primary productivity, the fixation of carbon dioxide into organic matter by plants. In my thesis, I addressed the following three questions: 1.) What will be the relative effect of changes in the mean and standard deviation of annual precipitation on mean annual primary production? 2.) Which ecosystems will be the most sensitive to changes in precipitation? 3.) Will …


An Embedded Atom Method Investigation Into The Lattice Dynamics Of Metallic Surfaces, Richard B. Wilson Dec 2011

An Embedded Atom Method Investigation Into The Lattice Dynamics Of Metallic Surfaces, Richard B. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The explosion in electronic devices over the last half century is a result of the successful development and application of theories that explain the physical properties of solids. For example, the theory of lattice vibrations developed in the first half of the 20th century has had a huge impact on our ability to understand and design devices. The idea that atoms vibrate together in grouped vibrational modes, called phonons, has enabled scientists to quantify the impact that atomic motion has on mechanical, thermal, electrical, and optical properties. This has aided the creation of all sorts of useful technology ranging …


A Dynamic State Metabolic Journey: From Mass Spectrometry To Network Analysis Via Estimation Of Kinetic Parameters, Arockia Ranjitha Dhanasekaran Dec 2011

A Dynamic State Metabolic Journey: From Mass Spectrometry To Network Analysis Via Estimation Of Kinetic Parameters, Arockia Ranjitha Dhanasekaran

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The term "metabolism" refers to the chemical processes occurring in a living organism to convert the food consumed into the energy needed to maintain a living state. Metabolism consists of two states, namely, a dynamic state and a steady state. In the dynamic state, the rate of chemical conversion of a substance is proportional to the amount of substance available, whereas in the steady state this rate is constant and independent of the amount of substance present (Chapter 4 Figure 1). Like all other fields of engineering, metabolic engineering involves the analysis and synthesis of metabolism. Molecular biological tools for …


Temperature Dependence Of Sio2 Electron-Induced Luminescence, Amberly Evans Jensen, Gregory Wilson, Jr Dennison Nov 2011

Temperature Dependence Of Sio2 Electron-Induced Luminescence, Amberly Evans Jensen, Gregory Wilson, Jr Dennison

Presentations

No abstract provided.


Exploring The Universe… One Electron At A Time, Jr Dennison Nov 2011

Exploring The Universe… One Electron At A Time, Jr Dennison

Presentations

No abstract provided.


Electron Energy Dependent Charging Effects Of Multilayered Dielectric Materials, Gregory Wilson, Amberly Evans Jensen, Jr Dennison Nov 2011

Electron Energy Dependent Charging Effects Of Multilayered Dielectric Materials, Gregory Wilson, Amberly Evans Jensen, Jr Dennison

Presentations

No abstract provided.


New Insights Into The Outlet Conditions Of Late Pleistocene Lake Bonneville, Southeastern Idaho, Usa, Susanne U. Janecke, Robert Q. Oaks Jr. Nov 2011

New Insights Into The Outlet Conditions Of Late Pleistocene Lake Bonneville, Southeastern Idaho, Usa, Susanne U. Janecke, Robert Q. Oaks Jr.

Susanne U. Janecke

Geologic, geomorphic, and geophysical analyses of landforms, sediments, and structures in northern Cache Valley, USA, document a revised history of flooding and recession of Lake Bonneville, the world's premier pluvial lake. Crosscutting relationships suggest that the Riverdale fault produced a surface-rupturing earthquake ∼25 km southeast of Zenda shortly before, during, or after the Bonneville flood, as well as possible younger surface ruptures. Thus fluctuating stresses and pore pressure induced by changing lake levels may have triggered a large earthquake that, in turn, triggered the Bonneville flood. The flood scoured ∼25 km of Cache and Marsh Valleys and activated landslides during …


Enhanced Lunar Semidiurnal Equatorial Vertical Plasma Drifts During Sudden Stratospheric Warmings, Bela G. Fejer, B. D. Tracy, J. L. Chau Nov 2011

Enhanced Lunar Semidiurnal Equatorial Vertical Plasma Drifts During Sudden Stratospheric Warmings, Bela G. Fejer, B. D. Tracy, J. L. Chau

Bela G. Fejer

[1] Large scale electrodynamic and plasma density variations in the low latitude ionosphere have recently been associated with sudden stratospheric warming (SSW) events. We present average patterns of largely enhanced lunar semidiurnal equatorial vertical plasma drift perturbations during arctic winter low and high solar flux SSW events. These perturbations play a dominant role in the electrodynamic response of the low latitude ionosphere to SSWs. Our models indicate that the amplitudes of the enhanced lunar semidiurnal drifts are strongly local time and solar flux dependent, with largest values during early morning low solar flux SSW periods. These results suggest that ionospheric …


Fabrication And Performance Of A Microfluidic Traveling-Wave Electrophoresis System, K. D. Jo, J. E. Schiffbauer, Boyd F. Edwards, R. L. Carroll, A. T. Timperman Nov 2011

Fabrication And Performance Of A Microfluidic Traveling-Wave Electrophoresis System, K. D. Jo, J. E. Schiffbauer, Boyd F. Edwards, R. L. Carroll, A. T. Timperman

All Physics Faculty Publications

A microfluidic traveling-wave electrophoresis (TWE) system is reported that uses a locally defined traveling electric field wave within a microfluidic channel to achieve band transport and separation. Low voltages, over a range of −0.5 to +0.5 V, are used to avoid electrolysis and other detrimental redox reactions while the short distance between electrodes, 25 μm, provides high electric fields of 200 V cm−1. It is expected that the low voltage requirements will simplify the future development of smaller portable devices. The TWE device uses four interdigitated electrode arrays: one interdigitated electrode array pair is on the top of …


From The Big Bang To The Swaner Ecocenter: The Cosmic Biography Of Atoms, Shane L. Larson Oct 2011

From The Big Bang To The Swaner Ecocenter: The Cosmic Biography Of Atoms, Shane L. Larson

Public Talks

No abstract provided.


Temperature Dependence Of Sio2 Electron-Induced Luminescence, Amberly Evans Jensen, Gregory Wilson, Jr Dennison Oct 2011

Temperature Dependence Of Sio2 Electron-Induced Luminescence, Amberly Evans Jensen, Gregory Wilson, Jr Dennison

Presentations

No abstract provided.


Electron Energy Dependent Charging Effects Of Multilayered Dielectric Materials, Gregory Wilson, Amberly Evans Jensen, Jr Dennison Oct 2011

Electron Energy Dependent Charging Effects Of Multilayered Dielectric Materials, Gregory Wilson, Amberly Evans Jensen, Jr Dennison

Presentations

No abstract provided.


Temperature Dependence Of Sio2 Electron-Induced Cathodoluminescence, Amberly Evans, Gregory Wilson, John R. Dennison Oct 2011

Temperature Dependence Of Sio2 Electron-Induced Cathodoluminescence, Amberly Evans, Gregory Wilson, John R. Dennison

All Physics Faculty Presentations

No abstract provided.


Development Of A Passive Sampler For Gaseous Mercury, Mae S. Gustin, Seth N. Lyman, P. Kilner, E. Prestbo Oct 2011

Development Of A Passive Sampler For Gaseous Mercury, Mae S. Gustin, Seth N. Lyman, P. Kilner, E. Prestbo

USU Uintah Basin Faculty Publications

Here we describe work toward development of the components of a cost effective passive sampling system for gaseous Hg that could be broadly deployed by nontechnical staff. The passive sampling system included an external shield to reduce turbulence and exposure to precipitation and dust, a diffusive housing that directly protects the collection surface during deployment and handling, and a collection surface. A protocol for cleaning and deploying the sampler and an analytical method were developed. Our final design consisted of a polycarbonate external shield enclosing a custom diffusive housing made from expanded PTFE tubing. Two collection surfaces were investigated, gold …


Morse Theory For C*-Algebras: A Geometric Interpretation Of Some Noncommutative Manifolds, Vida Milani, Ali Asghar Rezaei, Seyed M.H. Mansourbeigi Oct 2011

Morse Theory For C*-Algebras: A Geometric Interpretation Of Some Noncommutative Manifolds, Vida Milani, Ali Asghar Rezaei, Seyed M.H. Mansourbeigi

Computer Science Student Research

The approach we present is a modification of the Morse theory for unital C*-algebras. We provide tools for the geometric interpretation of noncommutative CW complexes. Some examples are given to illustrate these geometric information. The main object of this work is a classification of unital C*-algebras by noncommutative CW complexes and the modified Morse functions on them.


Biogeochemical Response Of Alpine Lakes To A Recent Increase In Dust Deposition In The Southwestern, Us, Ashley P. Ballantyne, Janice Brahney, C. L. Lawrence, J. Saros, Jason C. Neff Sep 2011

Biogeochemical Response Of Alpine Lakes To A Recent Increase In Dust Deposition In The Southwestern, Us, Ashley P. Ballantyne, Janice Brahney, C. L. Lawrence, J. Saros, Jason C. Neff

Watershed Sciences Faculty Publications

The deposition of dust has recently increased significantly over some regions of the western US. Here we explore how changes in dust deposition have affected the biogeochemistry of two alpine watersheds in Colorado, US. We first reconstruct recent changes in the mass accumulation rate of sediments and then we use isotopic measurements in conjunction with a Bayesian mixing model to infer that approximately 95% of the inorganic fraction of lake sediments is derived from dust. Elemental analyses of modern dust indicate that dust is enriched in Ca, Cr, Cu, Mg, Ni, and in one watershed, Fe and P relative to …


Probing The Cosmos With Light And Gravity: Multi-Messenger Astronomy In The Gravitational Wave Era, Shane L. Larson Sep 2011

Probing The Cosmos With Light And Gravity: Multi-Messenger Astronomy In The Gravitational Wave Era, Shane L. Larson

Colloquia and Seminars

No abstract provided.


Sources Of Gaseous Oxidized Mercury And Mercury Dry Deposition At Two Southeastern U.S. Sites, Peter S. Weiss-Penzias, Mae S. Gustin, Seth N. Lyman Sep 2011

Sources Of Gaseous Oxidized Mercury And Mercury Dry Deposition At Two Southeastern U.S. Sites, Peter S. Weiss-Penzias, Mae S. Gustin, Seth N. Lyman

USU Uintah Basin Faculty Publications

Wet deposition measurements have shown that relative to other parts of the US, the southeastern region has the highest mercury (Hg) inputs. The source of this Hg has been investigated by multiple researchers and is suggested to be derived from local, regional and global sources. Here we focus on trying to understand potential sources of Hg to this area during periods dominated by dry gaseous oxidized mercury (GOM) deposition. Dry deposition of GOM to a surrogate surface was measured in conjunction with speciated atmospheric Hg, and ancillary parameters from September 2007 through September 2008 at two sites located within 25 …


Classical Fano Oscillator, D. Mark Riffe Aug 2011

Classical Fano Oscillator, D. Mark Riffe

All Physics Faculty Publications

Starting from the quantum-mechanical Fano-Anderson Hamiltonian, we derive classical equations of motion for coordinates associated with the discrete and continuum states. The frequency-dependent absorption spectrum associated with this classical system exhibits the same Fano line shape as the quantum-mechanical system when appropriate correspondences between classical and quantum variables are made. In the time domain, the response of this classical Fano oscillator depends upon the asymmetry parameter q that appears in the expression for the Fano line shape. In particular, under the influence of impulsive driving of the system, the discrete oscillator's phase changes by ±π/2 as q increases from zero …


Whispers From The Cosmos: The Dawn Of Gravitational Wave Astronomy, Shane L. Larson Aug 2011

Whispers From The Cosmos: The Dawn Of Gravitational Wave Astronomy, Shane L. Larson

Public Talks

No abstract provided.