Physical Sciences and Mathematics Commons^™

Photoelectric Charging By Ultraviolet Light Of A Lunar Dust Simulant In A Microgravity Environment, Troy Munro, Andrew Fassmann, Jr Dennison

Posters

A microgravity experiment to test the electrostatic behavior of a lunar dust simulant being charged through the photoelectric effect will expand understanding of the charging characteristics of dust particles and may lead to a possible mitigation solution. With a design based upon Robert Milikan's oil-drop experiment, this experiment is designed to observe the interactions of a lunar dust simulant without the conflicting effects of a dominant gravitational force. The dust particles will be charged by means of a lamp capable of photon energies necessary to emit electrons by the photoelectric effect. In the presence of an axial electric field, the …

Funboe Factsheet, Getaway Special Team 2009

Reports and Proposals

No abstract provided.

Sides: Space Italian Dressing Experimental Setup, Getaway Special Team 2009

Reports and Proposals

No abstract provided.

Ipas: International Paper Airplanes In Space, Getaway Special Team 2009

Reports and Proposals

No abstract provided.

Rembrant: Research On The Effects Of Microgravity On The Brazil Nut Problem, Getaway Special Team 2009

Reports and Proposals

No abstract provided.

Wild Horse Gathering For The Red Desert Complex Wild Horse Herd Management Areas (Lost Creek, Stewart Creek, Green Mountain, Crooks Mountain, Antelope Hills), United States Department Of The Interior, Bureau Of Land Management

Environmental Assessments (WY)

This Environmental Assessment (EA) has been prepared to disclose and analyze the environmental consequences of gathering excess wild horses in the Red Desert Wild Horse Herd Management Area (HMA) Complex. The HMAs included in this complex are Lost Creek, Stewart Creek, Green Mountain, Crooks Mountain and Antelope Hills. The EA is a site-specific analysis of potential impacts that could result with the implementation of a proposed action or alternatives to the proposed action. The EA assists the BLM in project planning and ensuring compliance with the National Environmental Policy Act (NEPA), and in making a determination as to whether any …

Superposition Formulas For Darboux Integrable Exterior Differential Sys-Tems, Ian M. Anderson, Mark E. Fels, Peter J. Vassiliou

Mathematics and Statistics Faculty Publications

In this article we solve an inverse problem in the theory of quotients for differential equations. We characterize a family of exterior differential systems that can be written as a quotient of a direct sum of two associated systems that are constructed from the original. The fact that a system can be written as a quotient can be used to find the general solution to these equations. Some examples are given to demonstrate the theory.

An Investigation Of The Ends Of Finitely Generated Groups, Daniel T. Murphree

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

Geometric group theory is a relatively new branch of mathematics, studied as a distinct area since the 1990's. It explores invariant properties of groups based on group actions defined on topological or geometrical spaces. One of the pioneering works in geometric group theory is the article "Topological Methods in Group Theory" by Peter Scott and Terry Wall, written in 1977. This article was an overview of revised notes from an advanced course give in Liverpool in the same year. This report is an attempt to make these notes more accessible to lower level graduate students in the fields of topology …

Arkosic Rocks From The San Andreas Fault Observatory At Depth (Safod)Borehole, Central California, S. D. Springer, J. P. Evans, J. I. Garver, D. Kirschner, Susanne U. Janecke

Susanne U. Janecke

http://lithosphere.geoscienceworld.org/content/1/4/206 The San Andreas Fault Observatory at Depth (SAFOD) drill hole encountered indurated, high-seismic-velocity arkosic sedimentary rocks west of the active trace of the San Andreas fault in central California. The arkosic rocks are juxtaposed against granitic rocks of the Salinian block to the southwest and against fine-grained Great Valley Group and Jurassic Franciscan rocks to the northeast. We identify three distinct lithologic units using cuttings, core petrography, electrical resistivity image logs, zircon fission-track analyses, and borehole-based geophysical logs. The upper arkose occurs from 1920 to 2530 m measured depth (mmd) in the borehole and is composed of five structural …

Overviewand Summary Of The Spread F Experiment (Spreadfex), D. C. Fritts, M. A. Abdu, B. R. Batista, I. S. Batista, P. P. Batista, R. Buritii, B. R. Clemesha, J. Comberiate, T. Dautermann, E. De Paula, B. J. Fechine, Bela G. Fejer, D. Gobbi, J. Haase, F. Kalamabadi, B. Laughman, P. P. Lima, H. L. Liu, A. Medeiros, D. Pautet, F. Sao Sabbas, J. H.A. Sobral, P. Stamus, H. Takahashi, M. J. Taylor, S. L. Vadas, C. Wrasse

Bela G. Fejer

We provide here an overview of, and a summary of results arising from, an extensive experimental campaign (the Spread F Experiment, or SpreadFEx) performed from September to November 2005, with primary measurements in Brazil. The motivation was to define the potential role of neutral atmosphere dynamics, specifically gravity wave motions propagating upward from the lower atmosphere, in seeding Rayleigh-Taylor instability (RTI) and plasma bubbles extending to higher altitudes. Campaign measurements focused on the Brazilian sector and included ground-based optical, radar, digisonde, and GPS measurements at a number of fixed and temporary sites. Related data on convection and plasma bubble structures …

Climatology Of Early Night Equatorial Spread F Over Jicamarca, N. P. Chapagain, Bela G. Fejer

Bela G. Fejer

[1] We use radar observations from 1996 to 2006 to study the climatology of postsunset equatorial 3-m spread F irregularities over Jicamarca during all seasons. We show that the spread F onset times do not change with solar flux and that their onset heights, which occur near the altitude of the evening F region velocity vortex, increase linearly from about 260 to 400 km from solar minimum to solar maximum. Higher onset heights generally lead to stronger radar echoes. During the equinox, spread F onset occurs near vertical drift evening reversal times, while during the December solstice, they occur near …

Liposomes Recruit Ipac To The Shigella Flexneri Type Iii Secretion Apparatus Needle As A Final Step In Secretion Induction, C. R. Epler, Nicholas E. Dickenson, A. J. Olive, W. L. Picking, W. D. Picking

Chemistry and Biochemistry Faculty Publications

Shigella flexneri contact with enterocytes induces a burst of protein secretion via its type III secretion apparatus (TTSA) as an initial step in cellular invasion. We have previously reported that IpaD is positioned at the TTSA needle tip (M. Espina et al., Infect. Immuno. 74:4391-4400, 2006). From this position, IpaD senses small molecules in the environment to control the presentation of IpaB to the needle tip. This step occurs without type III secretion induction or IpaC recruitment to the S. flexneri surface. IpaC is then transported to the S. flexneri surface when target cell lipids are added, and this event …

Integrated Water Resources Management And Modeling At Multiple Spatial Scales In Jordan, David E. Rosenberg

Civil and Environmental Engineering Faculty Publications

Water shortages from intermittent public supplies are a major and expanding problem in the Hashemite Kingdom of Jordan. Yet individual users, utility managers, and government officials can improve access or cope with shortages in many ways. New supplies, more efficient use of existing resources, long-term investments to expand infrastructure and reduce leakage, and short-term measures to flexibly transfer, ration, or curtail some uses represent several different approaches for management. This paper reviews three separate systems analysis that use stochastic optimization with recourse. Analysis for individual residential users, the water utility serving 2.2 million residents in the capital Amman, and the …

Modeling Integrated Decisions For A Municipal Water System With Recourse And Uncertainties: Amman, Jordan, David E. Rosenberg, Jay Lund

Civil and Environmental Engineering Faculty Publications

Stochastic mixed-integer optimization is used to identify a portfolio of long- and short-term supply and conservation actions for a municipal water system to cost-effectively accommodate a distribution of water shortages. Alternative robust, grey-number, and best/worst case formulations systematically explore implications of uncertainties in action costs, life spans, water volumes gained or saved, shortage levels, and shortage probabilities. A detailed example for Amman, Jordan considers 23 potential actions. Results show: (1) remarkable consistency occurs across the different modeling approaches. (2) Conserving water—reducing leakage and targeting select customers to install water efficient appliances—plays an important and growing role over time. (3) A …

The Effects Of Model Misspecification On Linear Regression Coefficients As Applicable To Solar And Linear Terms, Troy A. Wynn, Vincent B. Wickwar

Reports

Determining atmospheric solar response from data is typically done by fitting a linear model to the data using a least squares approximation. These models typically include a solar proxy that follows the 11 year solar intensity variation, as well as a linear cooling trend. In this paper it is argued that such a regression model is flawed in that the atmospheric solar response might be out of phase with the solar input. And if so, the phase difference between solar input and atmospheric solar response can significantly bias the linear regression coefficient and attenuate the solar coefficient. This result is …

Fault Formation In Porous Sedimentary Rocks At High Strain Rates, Wendy R.O. Key

Canyonlands Research Bibliography

No abstract provided.

Convection: The Likely Source Of The Medium-Scale Gravity Waves Observed In The Oh Airglow Layer Near Brasilia, Brazil, During The Spreadfex Campaign, Sharon L. Vadas, Michael J. Taylor, Pierre-Dominique Pautet, P. A. Stamus, David C. Fritts, H. L. Liu, F. T. São Sabbos, V. T. Batista, H. Takahashi, V. T. Rampinelli

Publications

Six medium-scale gravity waves (GWs) with horizontal wavelengths of λH=60–160 km were detected on four nights by Taylor et al. (2009) in the OH airglow layer near Brasilia, at 15° S, 47° W, during the Spread F Experiment (SpreadFEx) in Brazil in 2005. We reverse and forward ray trace these GWs to the tropopause and into the thermosphere using a ray trace model which includes thermospheric dissipation. We identify the convective plumes, convective clusters, and convective regions which may have generated these GWs. We find that deep convection is the highly likely source of four of these GWs. We pinpoint …

Migration And Gender: The Case Of A Farming Ejido In Calakmul, Mexico, Claudia Radel, Birgit Schmook

Environment and Society Faculty Publications

As one of Mexico’s last agricultural frontiers, southern Mexico’s rural farming municipality of Calakmul has long been marked by rural in-migration. In the last few years this process has given place to an explosive growth of primarily male labor out-migration, particularly to the United States. The authors trace the outlines of the migration process from the perspective of one rural Calakmul community, to explore effects of men’s transnational migration on the household and community status of the women remaining behind. Analysis is based on quantitative data collected in 2004 from 25 households, and on in-depth qualitative interviews in 2005 with …

Los Maridos En El 'Norte'; Las Mujeres ¿Bien Gracias?, B. Schmook, Claudia Radel

Environment and Society Faculty Publications

La migración de mexicanos hacia Estados Unidos ha sido una constante en las relaciones entre ambas naciones desde hace más de siglo y medio, pero se ha intesificado considerablemente en las últimas tres décadas. Factores diversos como la vecindad geográfica, tendencias demográficas y laborales, la creciente integrción económica, la crisis del campo y las intensas relaciones e intercambios entre los dos países, hacen inevitable estos movimientos poblacionales.

Hydrologic Interdependencies And Human Cooperation: The Process Of Adapting To Droughts, Joanna Endter-Wada, Theresa Selfa, Lisa Welsh

Environment and Society Faculty Publications

The Bear River Basin, which includes portions of Idaho, Utah, and Wyoming in the United States, has a dynamic history of human hydrologic adaptations in relation to a highly variable water supply. These adaptations are embedded in a geographical setting highly influenced by the legal, policy, and institutional contexts that govern allocation of water in this generally arid region. In response to several years of drought and a historically low water year in 2004, water users in the Bear River Basin tested the efficacy of the “law of the river” and innovative agreements that they had negotiated in recent years …

Measurement Of Fine Spatial Scale Ecohydrologic Gradients In A Pinyon-Juniper Ecosystem, Matthew David Madsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the dramatic expansion of pinyon-juniper woodlands over the last century, improved understanding of how these woodlands modify infiltration properties is needed, in order for land managers to make informed decisions on how to best manage their specific resources. However, current methods for measuring soil infiltration are often limited by low sample sizes and high experimental error, due to constraints associated with remote, non agricultural settings. This thesis first presents a scheme for automating and calibrating two commercially available infiltrometers, which allows collection of a large number of precise unsaturated infiltration measurements in a relatively short period of time. Secondly, …

A Three-Dimensional, Time-Dependent Circulation Model Of Utah Lake, Eric V. Callister

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spatial and temporal variations of Utah Lake’s flow field were modeled using the Estuary Lake and Computer Model from the Centre for Water Research (CWR-ELCOM) at the University of Western Australia as part of an effort to increase understanding of the lake’s natural processes in order to restore the lake to its pristine, clear-water state and preserve the habitat of the June sucker, an endangered species. The model was validated using temperature measurements taken by sensors in 2007. The water temperature was a strong function of air temperature and incident short wave radiation, and was influenced to a lesser degree …

Intergranular Phases In Cyclically Annealed Yba2cu3o7-X And Their Implications For Critical Current Densities, Andrew Peter Clarke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We report changes in the intergranular material and grain morphology of YBa₂Cu₃O_7-x during cyclic anneals between 780 and 980 ºC in oxygen at atmospheric pressure. Two endothermic reactions were detected: (a) the eutectic reaction of YBa₂Cu₃O_7-x with CuO and BaCuO₂ at 900 ºC (enthalpy ∆H_a) and (b) the peritectic reaction of YBa₂Cu₃O_7-x with CuO at 950 ºC (∆H_b). During the first anneal, only reaction (b) is detected, and although it should only occur if there is an excess of CuO, …

Extending F10.7'S Time Resolution To Capture Solar Flare Phenomena, Ariel O. Acebal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solar ultraviolet (UV) radiation ionizes the neutral components in the atmosphere, which is partly responsible for the formation of the ionosphere, and contributes to heating of the atmosphere. Solar flares change the solar spectrum at times by several orders of magnitude. These changes modify the Earth's upper atmosphere, causing problems to communication systems and space operations, such as increased satellite drag. Unfortunately, solar UV measurements are limited since they can only be observed with space-based sensors. In order to work around this limitation, the solar radio emissions at a wavelength of 10.7 cm have been used as a proxy for …

Synthetic Complexes Of Relevance To Ni(Ii)-Containing Enzymes, Katarzyna Rudzka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work outlined herein presents an investigation of synthetic model complexes of relevance to the active sites of Ni(II)-containing enzymes, particularly urease, glyoxalase I, and acireductone dioxygenase. The research focuses on studying the structural and reactivity features of nickel complexes with biologically relevant substrates. The anion of acetohydroxamic acid is a well-known inhibitor of urease enzymes, including those isolated from Klebsiella aerogenes and Bacillus pasteurii. A precursor to the acetohydroxamate coordination in ureases is proposed to be an interaction between Ni(II) and acetohydroxamic acid. By using a novel supporting chelate ligand capable of secondary hydrogen bonding interactions a novel …

Threat Perception As A Determinant Of Pro-Environmental Behaviors: Public Involvement In Air Pollution Abatement In Cache Valley, Utah, Joshua D. Marquit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Threat perception related to environmental issues such as air pollution may be a determinant of pro-environmental behaviors. Among the potential threats of air pollution, include the perceived impacts on the psychological, social, and economic wellbeing of a community. Because of rapid increases in population growth, urbanization, and the mountainous landscapes, the American West is extremely susceptible to the adverse impacts of air pollution.

A secondary data analysis was conducted using data from the Air Quality Perception Survey conducted in Cache County, Utah. The survey focused on the public perception of air pollution in Cache County and perceived impact on personal …

Sources And Source Processes Of Organic Nitrogen Aerosols In The Atmosphere, Mark E. Erupe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research in this dissertation explored the sources and chemistry of organic nitrogen aerosols in the atmosphere. Two approaches were employed: field measurements and laboratory experiments. In order to characterize atmospheric aerosol, two ambient studies were conducted in Cache Valley in Northern Utah during strong winter inversions of 2004 and 2005. The economy of this region is heavily dependent on agriculture. There is also a fast growing urban population. Urban and agricultural emissions, aided by the valley geography and meteorology, led to high concentrations of fine particles that often exceeded the national ambient air quality standards. Aerosol composition was dominated …

Agent-Organized Network Coalition Formation, Levi L. Barton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents work based on modeling multi-agent coalition formation in an agent organized network. Agents choose which agents to connect with in the network. Tasks are periodically introduced into the network. Each task is defined by a set of skills that agents must fill. Agents form a coalition to complete a task by either joining an existing coalition a network neighbor belongs to, or by proposing a new coalition for a task no agents have proposed a coalition for. We introduce task patience and strategic task selection and show that they improve the number of successful coalitions agents form. …

Strides Towards Better Application Security, Sathyaraj Balasubramanian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Static analysis tools analyze source code for vulnerabilities. However, these types of tools suffer from various problems that limit their effectiveness. This thesis examines these static analysis tools and suggests techniques for making them more efficient at detecting different types of vulnerabilities.

The thesis further analyzes possible causes for these vulnerabilities by examining the source code written by programmers of various categories. Finally, this thesis discusses solutions and techniques to improve general security awareness as well as the importance of secure coding among the students and software developers.

Identification Of Subsoil Compaction Using Electrical Conductivity And Spectral Data Across Varying Soil Moisture Regimes In Utah, Jay Murray Payne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Subsoil compaction is a major yield limiting factor for most agricultural crops. Tillage is the most efficient method to quickly treat compacted subsoil, but it is also expensive, increases erosion, and accelerates nutrient cycling.

The use of real-time electrical conductivity (EC) and near-infrared (NIR) reflectance values to differentiate compacted areas from uncompacted areas was studied. This method has potential to reduce monetary and time investments inherent in traditional grid sampling and the resultant deep tillage of an entire field. EC and NIR reflectance are both very sensitive to spatial variability of soil attributes.

The objective of this research was to …