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Role Of Members Of The Phosducin Gene Family In Protein Translation And Folding, Nana Sono-Koree Mar 2010

Role Of Members Of The Phosducin Gene Family In Protein Translation And Folding, Nana Sono-Koree

Theses and Dissertations

G proteins regulate various physiological processes by way of transducing a wide variety of signals ranging from hormonal to sensory stimuli. Malfunctions in G protein signaling lead to numerous diseases. G protein signaling begins with binding of a ligand to a G protein-coupled receptor resulting in a conformational change that leads to the exchange of a GDP for a GTP on G α. The GTP bound α subunit dissociates for its stable Gβγ dimer partner. G α-GTP and Gβγ control the activity of effector enzymes and ion channels that ultimately orchestrate the cellular response to stimulus. Current reports have shown …

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Automatic Identification And Tracking Of Retraction Fibers In Time-Lapse Microscopy, Meher Talat Shaikh Mar 2010

Automatic Identification And Tracking Of Retraction Fibers In Time-Lapse Microscopy, Meher Talat Shaikh

Theses and Dissertations

Digital image processing is widely used in the field of time-lapse microscopy and biological research to provide statistical data of cellular dynamics. The data can provide more comprehensive understanding of the molecular phenomenon. Further, digital image processing enables rapid and consistent quantification of qualitative observations. The image processing model examined here provides a study to identify structures called retraction fibers (RFs) that are formed during epithelial-mesenchymal transition (EMT) [1], an important developmental process which also occurs during cancer metastasis. Quantifying RF formation is an important task for biologists studying cellular regulation of EMT. This thesis work uses digital image processing …

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Aerial Recovery Of Micro Air Vehicles: Orbit Estimation And Tracking, Daniel Clarke Carlson Mar 2010

Aerial Recovery Of Micro Air Vehicles: Orbit Estimation And Tracking, Daniel Clarke Carlson

Theses and Dissertations

Aerial recovery of autonomous micro air vehicles (MAVs) presents many unique challenges due to the difference in size and speed of the recovery vehicle and MAV. This thesis presents algorithms to enable an autonomous MAV to estimate the orbit of a recovery vehicle and track the orbit until the final docking phase. Methods for estimating ellipses that are rotated out of the x − y plane are developed and demonstrated through simulation. These algorithms are shown to be robust to noise and stable numerically. Parameter update methods that are computationally inexpensive, such as recursive least squares and Kalman filtering, are …

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Effects Of Computer-Based, Early-Reading Academic Learning Time On Early-Reading Achievement: A Dose-Response Approach, Benjamin Heuston Mar 2010

Effects Of Computer-Based, Early-Reading Academic Learning Time On Early-Reading Achievement: A Dose-Response Approach, Benjamin Heuston

Theses and Dissertations

Academic learning time (ALT) has long had the theoretical underpinnings sufficient to claim a causal relationship with academic achievement, but to this point empirical evidence has been lacking. This dearth of evidence has existed primarily due to difficulties associated with operationalizing ALT in traditional educational settings. Recent advancements in computer-based instruction provide an unprecedented opportunity to model ALT and to test the underlying theory. A widely-used computer-based early-reading curriculum was operationalized using Berliner's model of ALT (Berliner, 1991). This curriculum was then mapped to a computer-based assessment to determine an appropriate method of quantifying early-reading ALT. Software limitations required that …

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Recognizing Parametric Geometry From Topology Optimization Results, Shane H. Larsen Mar 2010

Recognizing Parametric Geometry From Topology Optimization Results, Shane H. Larsen

Theses and Dissertations

Topology Optimization has been proven to be a useful tool in discovering non-intuitive optimal designs subject to certain design constraints. The results of Topology Optimization are either represented as a tessellation object composed of thousands of triangular surfaces, or as a point cloud. In either case, the results of Topology Optimization are not suited for use in subsequent steps of the design process which require 3D parametric CAD (Computer Aided Design) models. Converting Topology Optimization results into parametric CAD geometry by hand is an extremely tedious and time consuming process which is highly subjective. This thesis presents a shape recognition …

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Characterization Of Optical Constants For Uranium From 10 To 47 Nm, Nicole Brimhall, Nicholas Herrick, David D. Allred, R. Steven Turley, Michael Ware, Justin Peatross Mar 2010

Characterization Of Optical Constants For Uranium From 10 To 47 Nm, Nicole Brimhall, Nicholas Herrick, David D. Allred, R. Steven Turley, Michael Ware, Justin Peatross

Faculty Publications

We use a laser high-harmonics-based extreme-ultraviolet (EUV) polarimeter to determine the optical constants of elemental uranium in the wavelength range from 10 to 47 nm. The constants are extracted from the measure ratio of p-polarized to s-polarized reflectance from a thin uranium film deposited in situ. The film thickness is inferred from a spectroscopic ellipsometry measurement of the sample after complete oxidation in room air. Uranium has been used as a high-reflectance material in the EUV. However, difficulties with oxidation prevented its careful characterization previous to this study. We find that measured optical constants for uranium vary significantly from previous …

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Generalized Image Formation For Pulsed And Lfm-Cw Synthetic Aperture Radar, Evan C. Zaugg Mar 2010

Generalized Image Formation For Pulsed And Lfm-Cw Synthetic Aperture Radar, Evan C. Zaugg

Theses and Dissertations

Approximations made in the traditional signal model for synthetic aperture radar (SAR) processing cause defocusing of the radar images when the system operates under conditions where the approximations lose validity. This dissertation investigates a number of these approximations and presents algorithmic improvements based on generalizations of the approxmations of the SAR signal model. These improvements result in better focused imagery from SAR systems with varied designs and parameters. Among the advancements presented is the development of a generalized chirp-scaling algorithm and a generalized frequency scaling algorithm to address the problems caused by approximations based on a Taylor series expansion of …

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Testing Models Related To The Laramide Uplift Of The Uinta Mountains And Geologic Mapping Of The Jessen Butte 7.5 Minute Quadrangle, Dagget County, Utah And Sweetwater County, Wyoming, Coreen Hurst Mar 2010

Testing Models Related To The Laramide Uplift Of The Uinta Mountains And Geologic Mapping Of The Jessen Butte 7.5 Minute Quadrangle, Dagget County, Utah And Sweetwater County, Wyoming, Coreen Hurst

Theses and Dissertations

Geologic mapping of the Jessen Butte 7.5 minute quadrangle and the gathering of structural data throughout the quadrangle was used to determine the paleostress regime during the Laramide Orogeny along the north flank of the Uinta Mountains. The Henrys Fork thrust fault and the Uinta thrust fault are major north bounding faults and within the Jessen Butte quadrangle these faults transfer deformation from one to the other. The Jessen Butte thrust fault is a fault splay that splits off from the Henrys Fork thrust fault. Complex fold geometries were created by the interaction of the faults. Bedding plane orientation, mode …

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The Asymmetric Phase-Transfer Catalyzed Alkylation Of Imidazolyl Ketones And Aryl Acetates And Their Applications To Total Synthesis, Michael Andrew Christiansen Mar 2010

The Asymmetric Phase-Transfer Catalyzed Alkylation Of Imidazolyl Ketones And Aryl Acetates And Their Applications To Total Synthesis, Michael Andrew Christiansen

Theses and Dissertations

Phase-transfer catalysts derived from the cinchona alkaloids cinchonine and cinchonidine are widely used in the asymmetric alkylation of substrates bearing moieties that resonance stabilize their enolates. The investigation of α-oxygenated esters revealed decreased α-proton acidity, indicating the oxygen's overall destabilizing effect on enolates by electron-pair repulsion. Alkylation of α-oxygenated aryl ketones with various alkyl halides proved successful with a cinchonidine catalyst, giving products with high yield and enantioselectivity. The resulting compounds were converted to esters through modified Baeyer-Villiger oxidation. Alkylation with indolyl electrophiles gave products that underwent decomposition under Baeyer-Villiger conditions. Alternative N-methylimidazolyl ketones were explored. Alkylated imidazolyl ketones, obtained …

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A Bayesian Decision Theoretical Approach To Supervised Learning, Selective Sampling, And Empirical Function Optimization, James Lamond Carroll Mar 2010

A Bayesian Decision Theoretical Approach To Supervised Learning, Selective Sampling, And Empirical Function Optimization, James Lamond Carroll

Theses and Dissertations

Many have used the principles of statistics and Bayesian decision theory to model specific learning problems. It is less common to see models of the processes of learning in general. One exception is the model of the supervised learning process known as the "Extended Bayesian Formalism" or EBF. This model is descriptive, in that it can describe and compare learning algorithms. Thus the EBF is capable of modeling both effective and ineffective learning algorithms. We extend the EBF to model un-supervised learning, semi-supervised learning, supervised learning, and empirical function optimization. We also generalize the utility model of the EBF to …

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Planar Cat(K) Subspaces, Russell M. Ricks Mar 2010

Planar Cat(K) Subspaces, Russell M. Ricks

Theses and Dissertations

Let M_k^2 be the complete, simply connected, Riemannian 2-manifold of constant curvature k ± 0. Let E be a closed, simply connected subspace of M_k^2 with the property that every two points in E are connected by a rectifi able path in E. We show that E is CAT(k) under the induced path metric.

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Convenient Decentralized Authentication Using Passwords, Timothy W. Van Der Horst Mar 2010

Convenient Decentralized Authentication Using Passwords, Timothy W. Van Der Horst

Theses and Dissertations

Passwords are a very convenient way to authenticate. In terms of simplicity and portability they are very difficult to match. Nevertheless, current password-based login mechanisms are vulnerable to phishing attacks and typically require users to create and manage a new password for each of their accounts. This research investigates the potential for indirect/decentralized approaches to improve password-based authentication. Adoption of a decentralized authentication mechanism requires the agreement between users and service providers on a trusted third party that vouches for users' identities. Email providers are the de facto trusted third parties on the Internet. Proof of email address ownership is …

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Methods To Streamline Laminate Composite Design, Analysis, And Optimization, Ammon Ikaika No Kapono Hepworth Mar 2010

Methods To Streamline Laminate Composite Design, Analysis, And Optimization, Ammon Ikaika No Kapono Hepworth

Theses and Dissertations

Advanced composite materials have seen major market growth in recent years due to their high strength and low weight properties. These materials are often made using a process that creates a composite laminate by stacking several composite layers together. However, the design, analysis and optimization of laminate composite materials are often a labor intensive process when done manually. This thesis discusses CAD independent algorithms that are integrated into commercial CAD tools to streamline these processes. Methods have been developed to automatically create 3D ply geometry for a laminate composite lay-up, streamline the creation of a laminate composite finite element model …

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Number, Newtonianism, And Sublimity In James Thomson's The Seasons, Jessie Leatham Wirkus Mar 2010

Number, Newtonianism, And Sublimity In James Thomson's The Seasons, Jessie Leatham Wirkus

Theses and Dissertations

Recently, literary critics have increasingly drawn on methods of quantitative analysis to understand the readers and literature of the eighteenth century. Ironically, however, the eighteenth century is home to debates concerning the nature and usefulness of number, counting, and therefore, on some level, quantitative analysis. Eighteenth-century questions of number form an important part of the intellectual history of this period; these questions of number, in turn, hold important implications for language and the period's literature. I argue that the far-reaching influence of eighteenth-century questions of number can be seen especially well in the nature poetry of James Thomson. To explore …

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Multi-Aperture Coherent Change Detection And Interferometry For Synthetic Aperture Radar, David D. Madsen Mar 2010

Multi-Aperture Coherent Change Detection And Interferometry For Synthetic Aperture Radar, David D. Madsen

Theses and Dissertations

Interferometry and coherent change detection (CCD) utilize phase differences between complex SAR images to find terrain height and to detect small changes between images, respectively. A new method for improving interferometry and CCD using multiple sub-apertures is proposed. Using backprojection processing, multiple sub-aperture images are created for a pair of flights. An interferogram and coherence map is made from each sub-aperture. For CCD, each sub-aperture coherence map offers an independent estimate of the coherence over the same area. By combining coherence maps, low coherence areas associated with residual motion errors are reduced, shadowed areas are minimized, and the overall coherence …

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Integrating Facies Analysis, Terrestrial Sequence Stratigraphy, And The First Detrital Zircon (U-Pb) Ages Of The Twist Gulch Formation, Utah, Usa: Constraining Paleogeography And Chronostratigraphy, Tyson L. Perkes Mar 2010

Integrating Facies Analysis, Terrestrial Sequence Stratigraphy, And The First Detrital Zircon (U-Pb) Ages Of The Twist Gulch Formation, Utah, Usa: Constraining Paleogeography And Chronostratigraphy, Tyson L. Perkes

Theses and Dissertations

The Jurassic Twist Gulch Formation of central Utah was deposited in the active Arapien sub-basin of the Western Cordillera foreland trough. We herein demonstrate the utility of integrating facies analysis, terrestrial sequence stratigraphy, and detrital zircon (U-Pb) ages to improve paleogeographic reconstructions as well as identify regional unconformities, locate fluvial depocenters, and infer sediment supply/accommodation space ratios. Strata of the Twist Gulch Formation in Pigeon Creek Canyon (PCC) near Levan, Utah consists primarily of alluvial deposits, while in Salina Canyon (SC) the Twist Gulch Formation is comprised of a mix of alluvial and marginal marine deposits associated with the Jurassic …

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Parameter Estimation And Hypothesis Testing For The Truncated Normal Distribution With Applications To Introductory Statistics Grades, James T. Hattaway Mar 2010

Parameter Estimation And Hypothesis Testing For The Truncated Normal Distribution With Applications To Introductory Statistics Grades, James T. Hattaway

Theses and Dissertations

The normal distribution is a commonly seen distribution in nature, education, and business. Data that are mounded or bell shaped are easily found across various fields of study. Although there is high utility with the normal distribution; often the full range can not be observed. The truncated normal distribution accounts for the inability to observe the full range and allows for inferring back to the original population. Depending on the amount of truncation, the truncated normal has several distinct shapes. A simulation study evaluating the performance of the maximum likelihood estimators and method of moment estimators is conducted and a …

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Interactive Television News, Derek L. Bunn Mar 2010

Interactive Television News, Derek L. Bunn

Theses and Dissertations

We design and evaluate a way to modify television news to make it interactive for viewers. We allow them to get more of what they want and less of what they don't want. This allows news to break constraints imposed by television broadcast schedules. Our solution is to augment the existing news broadcast structure in the following ways: add a video headlines menu, provide on-demand access to additional story content, provide interactive navigation controls between stories, and a control overlay. For news producers we create a video annotation program and process to help create the interactive news. We use the …

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Contextualized Motivation Theory (Cmt): Intellectual Passion, Mathematical Need, Social Responsibility, And Personal Agency In Learning Mathematics, Janelle Marie Hart Mar 2010

Contextualized Motivation Theory (Cmt): Intellectual Passion, Mathematical Need, Social Responsibility, And Personal Agency In Learning Mathematics, Janelle Marie Hart

Theses and Dissertations

Student motivation has long been a concern of mathematics educators. Here, I characterize motivation, defined as an individual's desire to act in particular ways, through analysis of students' extended, collaborative problem solving efforts. Grounded in a longitudinal research project in calculus learning and teaching, Contextualized Motivation Theory (CMT) offers a means for understanding the complexities of student motivations in mathematics learning. Students in this study chose to act upon various intellectual-mathematical motivations and social-personal motivations, existing simultaneously, within a supporting "web" of motivations. Students exhibited intellectual passion in persisting beyond obtaining correct answers to build understandings of mathematical ideas. CMT …

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Time-Resolved Infrared Spectroscopy And Density Functional Theory Study Of Weak Interactions Of Metal Carbonyls And Organic Solvents, Carolyn Evans Sheffield Mar 2010

Time-Resolved Infrared Spectroscopy And Density Functional Theory Study Of Weak Interactions Of Metal Carbonyls And Organic Solvents, Carolyn Evans Sheffield

Theses and Dissertations

Pulsed laser flash photolysis of M(CO)6 (M = Cr, W) in cyclohexane with a small amount of benzene results in three sequential reactions. The first is the photodissociation of the parent to yield a M(CO)5:C6H12 complex, which takes place faster than the time resolution of our experiments. The second reaction is the replacement of the cyclohexane ligand with benzene to form a M(CO)5:C6H6 complex, in which benzene is coordinated to the metal via one side of the ring. This complex then falls apart in solution as M(CO)5 coordinates with a trace impurity in the solution that is likely water. Kinetic …

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Uav Video Coverage Quality Maps And Prioritized Indexing For Wilderness Search And Rescue, Cameron Engh, Michael A. Goodrich, Bryan S. Morse Mar 2010

Uav Video Coverage Quality Maps And Prioritized Indexing For Wilderness Search And Rescue, Cameron Engh, Michael A. Goodrich, Bryan S. Morse

Faculty Publications

Video-equipped mini unmanned aerial vehicles (mini-UAVs) are becoming increasingly popular for surveillance, remote sensing, law enforcement, and search and rescue operations, all of which rely on thorough coverage of a target observation area. However, coverage is not simply a matter of seeing the area (visibility) but of seeing it well enough to allow detection of targets of interest, a quality we here call “see-ability”. Video flashlights, mosaics, or other geospatial compositions of the video may help place the video in context and convey that an area was observed, but not necessarily how well or how often. This paper presents a …

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Asian Spread Option Pricing Models And Computation, Sijin Chen Feb 2010

Asian Spread Option Pricing Models And Computation, Sijin Chen

Theses and Dissertations

In the commodity and energy markets, there are two kinds of risk that traders and analysts are concerned a lot about: multiple underlying risk and average price risk. Spread options, swaps and swaptions are widely used to hedge multiple underlying risks and Asian (average price) options can deal with average price risk. But when those two risks are combined together, then we need to consider Asian spread options and Asian-European spread options for hedging purposes. For an Asian or Asian-European spread call option, its payoff depends on the difference of two underlyings' average price or of one average price and …

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Studying The Performance Of Wireless Mesh Networks Using The Hxh Transport Control Protocol, Timothy Scott Larsen Feb 2010

Studying The Performance Of Wireless Mesh Networks Using The Hxh Transport Control Protocol, Timothy Scott Larsen

Theses and Dissertations

As the need to remain connected increases, more and more people are turning to wireless mesh networks because they reduce the need for network infrastructure. Unfortunately, TCP does not perform well in such networks. HxH, an alternate protocol, has shown great promise in simulations, but since it relies on exploiting passive feedback, real measurements are needed to determine how effective the protocol really is. This thesis uses a measurement study on a wireless mesh network to characterize the performance of the HxH protocol in real-world networks. Several aspects of the HxH protocol do in fact perform well on real networks, …

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The Heat Capacity And Thermodynamic Properties Of The Iron Oxides And Their Relation To The Mineral Core Of The Iron Storage Protein Ferritin, Claine Lindsey Morton Snow Feb 2010

The Heat Capacity And Thermodynamic Properties Of The Iron Oxides And Their Relation To The Mineral Core Of The Iron Storage Protein Ferritin, Claine Lindsey Morton Snow

Theses and Dissertations

The iron oxides are a group of materials with geological, biological, and technological importance. A thermodynamic understanding of these materials is important because it provides information about their relative stabilities, chemical reactivity, and transformations. This study provides the heat capacity of a nanocrystalline magnetite (Fe3O4) sample, bulk hematite (α-Fe2O3), nanocrystalline hematite, akaganéite (β-FeOOH), and lepidocrocite (γ-FeOOH) at temperatures as low as 0.5 K. These measurements were fit to theoretical functions at temperatures lower than 15 K, and the respective thermophysical properties of these materials are discussed. Also the molar entropies of bulk hematite and hydrous nanocrystalline hematite as well as …

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Redundant Journal Access: Why Pay More Than Once?, Jared L. Howland Feb 2010

Redundant Journal Access: Why Pay More Than Once?, Jared L. Howland

Faculty Publications

PDF of Powerpoint Presentation on journal access. This presentation was given at the Electronic Resources and Libraries 2010 Conference in Austin, Texas.

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Effect Of Prompted Reflection And Metacognitive Skill Instruction On University Freshmen's Use Of Metacognition, Dana Lynn Erskine Jan 2010

Effect Of Prompted Reflection And Metacognitive Skill Instruction On University Freshmen's Use Of Metacognition, Dana Lynn Erskine

Theses and Dissertations

Research in metacognition has long demonstrated that applying metacognitive strategies improves students learning and performance. Incoming college and university freshmen are not typically trained in using the metacognitive skills that could enhance their academic performance and their satisfaction with the college experience. This study attempted to assess first-year university students' metacognitive awareness and usage at two levels: (a) After direct and specific metacognitive training, (b) after engaging in weekly metacognitive reflection assignments. Six classes of university freshmen were studied in terms of their use of metacognitive skills and strategies as they progressed through their initial semester. Four of the six …

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Graph-Based Global Illumination, Brian C. Ricks Jan 2010

Graph-Based Global Illumination, Brian C. Ricks

Theses and Dissertations

The slow render times of global illumination algorithms make them impractical in most commercial and academic settings. We propose a novel framework for calculating the computational complexity of global illumination algorithms and show that no other recent improvements have reduced this complexity. We further show that many algorithms use a tree as their rendering paradigm. We propose a new rendering algorithm, pipe casting, which calculates light paths using a graph instead of a tree. Pipe casting significantly reduces both computational complexity and actual render time of rendering. Using an L2 pixel-wise error comparison, on average our algorithm can render a …

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Ordered Magnesium-Lithium Alloys: First-Principles Predictions, Richard H. Taylor, Gus L. W. Hart, Stefano Curtarolo Jan 2010

Ordered Magnesium-Lithium Alloys: First-Principles Predictions, Richard H. Taylor, Gus L. W. Hart, Stefano Curtarolo

Faculty Publications

Magnesium-lithium (Mg-Li) alloys are among the lightest structural materials. Although considerable work has been done on the Mg-Li system, little is known regarding potential ordered phases. A first and rapid analysis of the system with the high-throughput method reveals an unexpected wealth of potentially stable low-temperature phases. Subsequent cluster expansions constructed for bcc and hcp superstructures extend the analysis and verify our high-throughput results. Of particular interest are those structures with greater than 13 at. % lithium, as they exhibit either partial or complete formation as a cubic structure. Order-disorder transition temperatures are predicted by Monte Carlo simulations to be …

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Simulating The Fticr-Ms Signal Of A Decaying Beryllium-7 Ion Plasma In A 2d Electrostatic Pic Code, Michael Takeshi Nakata Jan 2010

Simulating The Fticr-Ms Signal Of A Decaying Beryllium-7 Ion Plasma In A 2d Electrostatic Pic Code, Michael Takeshi Nakata

Theses and Dissertations

Beryllium-7 (Be-7) only decays by electron capture into lithium-7 (Li-7) with a half life of 53 days. We study the effect of ionization on this decay rate. We do so by trapping a Be-7 ion plasma in a cylindrical Malmberg-Penning trap and measuring Be-7 and Li-7 concentrations as functions of time by using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). We have simulated these signals in a 2-dimensional electrostatic particle-in-cell (PIC) code. The two spectrum peaks merge at high ion densities whereas at low ion densities they can be resolved. The merged peak shifts linearly according to the relative …

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Representing Multi-Parent Organizational Structures For Use In High Performance Computing Resource Scheduling Algorithms, Lloyd T. Brown Jan 2010

Representing Multi-Parent Organizational Structures For Use In High Performance Computing Resource Scheduling Algorithms, Lloyd T. Brown

Theses and Dissertations

Historically, organizational structures of many universities and corporations have followed a strictly tree-based, hierarchical model. These organizations are defined with no more than one parent organization, and typically resource requirements for the organization could be derived from the parent organization. In recent years, however, many institutions have created interdisciplinary research groups which incorporate multiple fields of research across multiple campus organizations. For example, at Brigham Young University, there exists a biophysics research group, a child organization of both the Department of Biology and the Department of Physics, making it unclear how to define its resource requirements in the context of …

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