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The Enigmatic Young Object: Walker 90/V590 Monocerotis, M. D. Joner, M. R. Perez, B. Mccollum, M. E. Van Dend Ancker May 2008

The Enigmatic Young Object: Walker 90/V590 Monocerotis, M. D. Joner, M. R. Perez, B. Mccollum, M. E. Van Dend Ancker

Faculty Publications

Aims. We assess the evolutionary status of the intriguing object Walker 90/V590 Mon, which is located about 20 arcmin northwest of the Cone Nebula near the center of the open cluster NGC 2264. This object, according to its most recent optical spectral type determination (B7), which we confirmed, is at least 3 mag too faint in V for the cluster distance, but it shows the classical signs of a young pre-main sequence object, such as highly variable H emission, Mg II emission, IR excess, UV continuum, and optical variability. Methods. We analyzed a collection of archival and original data on …

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Quadrotor Dynamics And Control Rev 0.1, Randal Beard May 2008

Quadrotor Dynamics And Control Rev 0.1, Randal Beard

Faculty Publications

These notes outline quadrotor dynamics, state estimation, and control using a camera as the primary sensor.

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On The Steering Of Sound Energy Through A Supercritical Plate By A Near-Field Transducer Array, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes May 2008

On The Steering Of Sound Energy Through A Supercritical Plate By A Near-Field Transducer Array, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes

Faculty Publications

The ability to direct sound energy through the flexural vibrations of a submerged plate at various angles of incidence using a near-field transducer array is investigated. An alumina bar is placed in front of a one-dimensional, eight-element transducer array, between the array and the water. Operating in a receive mode, data were taken as a function of angle of incidence and compared to data taken without the presence of the alumina bar. The array was also operated in transmit mode and results were compared to corresponding receive mode data, showing that reciprocity holds. Results show that in fact sound energy …

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Automating Mini-Ontology Generation From Canonical Tables, Stephen G. Lynn Apr 2008

Automating Mini-Ontology Generation From Canonical Tables, Stephen G. Lynn

Theses and Dissertations

In this thesis work we develop and test MOGO (a Mini-Ontology GeneratOr.) MOGO automates the generation of mini-ontologies from canonicalized tables of data. This will help anyone trying to organize large amounts of existing data into a more searchable and accessible form. By using a number of different heuristic rules for selecting, enhancing, and modifying ontology elements, MOGO allows users to automatically, semi-automatically, or manually generate conceptual mini-ontologies from canonicalized tables of data. Ideally, MOGO operates fully automatically while allowing users to intervene to direct and correct when necessary so that they can always satisfactorily complete the translation of canonicalized …

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Contribution Of Recharge Along Regional Flow Paths To Discharge At Ash Meadows, Nevada, Michelle Bushman Apr 2008

Contribution Of Recharge Along Regional Flow Paths To Discharge At Ash Meadows, Nevada, Michelle Bushman

Theses and Dissertations

Springs in the Ash Meadows, Nevada wetland area are discharging groundwater at a high volume that cannot be sustained by local, present-day precipitation and associated recharge. Previous groundwater flow models for this region have required groundwater to flow through complex geology for long distances (160km) through fractures that, in the current stress field, should be closed in many instances in the presumed flow direction. This thesis examines several possible flow paths and evaluates each flow path using chemical and isotopic signatures in the water, as well as geologic and geophysical constraints, and determines that flow from beneath the Yucca Mountain …

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Geology Of The Phil Pico Mountain Quadrangle, Daggett County, Utah, And Sweetwater County, Wyoming, Alvin D. Anderson Apr 2008

Geology Of The Phil Pico Mountain Quadrangle, Daggett County, Utah, And Sweetwater County, Wyoming, Alvin D. Anderson

Theses and Dissertations

Geologic mapping in the Phil Pico Mountain quadrangle and analysis of the Carter Oil Company Carson Peak Unit 1 well have provided additional constraints on the erosional and uplift history of this section of the north flank of the Uinta Mountains. Phil Pico Mountain is largely composed of the conglomeratic facies of the early Eocene Wasatch and middle to late Eocene Bridger Formations. These formations are separated by the Henrys Fork fault which has thrust Wasatch Formation next to Bridger Formation. The Wasatch Formation is clearly synorogenic and contains an unroofing succession from the adjacent Uinta Mountains. On Phil Pico …

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Stabilization And Control Of A Quad-Rotor Micro-Uav Using Vision Sensors, Spencer G. Fowers Apr 2008

Stabilization And Control Of A Quad-Rotor Micro-Uav Using Vision Sensors, Spencer G. Fowers

Theses and Dissertations

Quad-rotor micro-UAVs have become an important tool in the field of indoor UAV research. Indoor flight poses problems not experienced in outdoor applications. The ability to be location- and movement-aware is paramount because of the close proximity of obstacles (walls, doorways, desks). The Helio-copter, an indoor quad-rotor platform that utilizes a compact FPGA board called Helios has been developed in the Robotic Vision Lab at Brigham Young University. Helios allows researchers to perform on-board vision processing and feature tracking without the aid of a ground station or wireless transmission. Using this on-board feature tracking system a drift stabilization control system …

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The Optimal Weighting Of Pre-Election Polling Data, Gregory K. Johnson Apr 2008

The Optimal Weighting Of Pre-Election Polling Data, Gregory K. Johnson

Theses and Dissertations

Pre-election polls are used to test the political landscape and predict election results. The relative weights for the state-level data from the 2006 U.S. senatorial races are considered based on the date on which the polls were conducted. Long- and short-memory weight functions are developed to specify the relative value of historical polling data. An optimal weight function is estimated by minimizing the discrepancy function between estimates from weighted polls and the election outcomes.

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Measurements And Modeling Of Coal Ash Deposition In An Entrained-Flow Reactor, Ryan P. Blanchard Apr 2008

Measurements And Modeling Of Coal Ash Deposition In An Entrained-Flow Reactor, Ryan P. Blanchard

Theses and Dissertations

Coal plays a significant role in meeting the world's need for energy and will continue to do so for many years to come. Economic, environmental, and public opinion are requiring coal derived energy to be cleaner and operate in a more narrow window of operating conditions. Fouling and slagging of heat transfer surfaces continues to be a challenge for maintaining boiler availability and expanding the use of available fuels and operating conditions. The work incorporates existing information in the literature on ash deposition into a User-Defined Function (UDF) for a commercial comprehensive combustion and CFD code. Results from the new …

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Exploring The Common Design Space Of Dissimilar Assembly Parameterizations For Interdisciplinary Design, Brady M. Larson Apr 2008

Exploring The Common Design Space Of Dissimilar Assembly Parameterizations For Interdisciplinary Design, Brady M. Larson

Theses and Dissertations

The use of parametric CAD models in engineering, analysis, and optimization has greatly enhanced the effectiveness and efficiency of the product development process. Parametric models provide an attractive avenue for expansive design exploration. There still exists, however, a great challenge for products requiring design input from multiple disciplines. The collaboration of engineering disciplines can be hampered by many factors including: competing design objectives, communication of design changes, the use of different design and analysis software, and different geometry definitions. These obstacles become compounded when developing products at the assembly level. The use of solid parametric assembly models is not readily …

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Generating Cad Parametric Features Based On Topology Optimization Results, William R. Blattman Apr 2008

Generating Cad Parametric Features Based On Topology Optimization Results, William R. Blattman

Theses and Dissertations

Shape optimization has become an important tool in industry to minimize weight and generate new designs. At the same time, companies are turning to CAD-centric design strategies where robust parametric CAD models are used to generate new designs and part-families of current designs, as well as the tooling and manufacturing procedures. However, due to its complexity, the optimal topology results are often discarded or recreated by hand into a CAD model. From a design stand point, the results can be improved with the use of manufacturing constraints on the shape optimization process. These constraints improve the manufacturability based on common …

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Metallicity And Effective Temperature Of The Secondary Or Rs Ophicuhi, R. L. Pearson Iii, Ya. V. Pavlenko, A. Evans, T. Kerr, L. Yakovina, C. E. Woodward, D. Lynch, R. Rudy, R. W. Russell Apr 2008

Metallicity And Effective Temperature Of The Secondary Or Rs Ophicuhi, R. L. Pearson Iii, Ya. V. Pavlenko, A. Evans, T. Kerr, L. Yakovina, C. E. Woodward, D. Lynch, R. Rudy, R. W. Russell

Faculty Publications

Context. The recurrent nova RS Ophiuchi undergoes nova eruptions every 10-20 years as a result of thermonuclear runaway on the surface of a white dwarf close to the Chandrasekhar limit. Both the progress of the eruption and its aftermath depend on the (poorly known) composition of the red giant in the RS Oph system. Aims. Our aim is to understand better the effect of the giant secondary on the recurrent nova eruption. Methods. Synthetic spectra were computed for a grid of M-giant model atmospheres having a range of effective temperatures 3200 < Teff < 4400 K, gravities 0 < log g < 1 and abundances -4 < [Fe/H] < 0.5, and fit to infrared spectra of RS Oph as it returned to quiescence after its 2006 eruption. We have modelled the infrared spectrum in the range 1.4-2.5µm to determine metallicity and effective temperature of the red giant. Results. We find Teff= 4100 ±100 K, log g = 0.0 ±0.5, [Fe/H] = 0.0 ±0.5, [C/H] = -0.8 ±0.2, [N/H] = +0.6 ±0.3 in the atmosphere of the secondary, and demonstrate that inclusion of some dust "veiling" in the spectra cannot improve our fits.

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Improving Spreadsheets For Complex Problems, Brian C. Whitmer Apr 2008

Improving Spreadsheets For Complex Problems, Brian C. Whitmer

Theses and Dissertations

Spreadsheets are one of the most frequently used applications. They are used because they are easy to understand and values can be updated easily. However, many people try to use spreadsheets for problems beyond their intended scope and end up with errors and miscalculations. We present a new spreadsheet system which uses complex-values and equation code reuse to overcome the limitations of spreadsheets for complex problems. We also discuss the features necessary in order to make these enhancements useful and effective.

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Generalized Constrained Interpolation, Jacob Porter Merrell Apr 2008

Generalized Constrained Interpolation, Jacob Porter Merrell

Theses and Dissertations

Interpolation is essential in digital image processing, especially magnification. Many different approaches to interpolation specific to magnification have been developed in an effort to overcome the shortcomings of bilinear and bicubic interpolation. One of these approaches, Constraint-Based Interpolation, produces an image that is free of jaggies and has less blurring than bilinear or bicubic interpolation. Although Constraint-Based Interpolation produces a visually pleasing image, there are user-chosen parameters that make the algorithm difficult to use. In this thesis we propose a method for automatic selection of those parameters and an extension of Constraint-Based Interpolation to other forms of image manipulation, such …

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Increasing Dogma Scaling Through Clustering, Nathan Hyrum Ekstrom Apr 2008

Increasing Dogma Scaling Through Clustering, Nathan Hyrum Ekstrom

Theses and Dissertations

DOGMA is a distributed computing architecture developed at Brigham Young University. It makes use of idle computers to provide additional computing resources to applications, similar to Seti@home. DOGMA's ability to scale to large numbers of computers is hindered by its strict client-server architecture. Recent research with DOGMA has shown that introducing localized peer-to-peer downloading abilities enhances DOGMA's performance while reducing the amount of network and server usage. This thesis proposes to further extend the peer-to-peer abilities of DOGMA to include peering client server communication by creating dynamic clusters of clients. The client clusters aggregate their communication with only one client …

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Corrado Giannantoni: A Modern-Day Newton, Donald L. Adolphson Apr 2008

Corrado Giannantoni: A Modern-Day Newton, Donald L. Adolphson

Journal of Microfinance / ESR Review

No abstract provided.

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Numerical Analysis Of Passive Force On Skewed Bridgeabutments With Reinforced Concrete Wingwalls, Scott Karl Snow Apr 2008

Numerical Analysis Of Passive Force On Skewed Bridgeabutments With Reinforced Concrete Wingwalls, Scott Karl Snow

Theses and Dissertations

Numerical Analysis of Passive Force on Skewed BridgeAbutments with Reinforced Concrete WingwallsScott Karl SnowDepartment of Civil and Environmental Engineering, BYU Master of Science Historically bridges with skewed abutments have proven more likely to fail during earthquake loadings (Toro et al, 2013) when compared to non-skewed bridges (Apirakvorapinit et al. 2012; Elnashai et al. 2010). Previous studies including small-scale laboratory tests by Jessee (2012), large-scale field tests by Smith (2014), and numerical modeling by Shamsabadi et al. (2006) have shown that 45° skewed bridge abutments experience a reduction in peak passive force by about 65%. With numerous skewed bridges in the …

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Skill Evaluation In Women's Volleyball, Lindsay W. Florence, Gilbert W. Fellingham, Pat R. Vehrs, Nina P. Mortensen Apr 2008

Skill Evaluation In Women's Volleyball, Lindsay W. Florence, Gilbert W. Fellingham, Pat R. Vehrs, Nina P. Mortensen

Faculty Publications

The Brigham Young University Women's Volleyball Team recorded and rated all skills (pass, set, attack, etc.) and recorded rally outcomes (point for BYU, rally continues, point for opponent) for the entire 2006 home volleyball season. Only sequences of events occurring on BYU's side of the net were considered. Events followed one of these general patterns: serve-outcome, pass-set-attack-outcome, or block-dig-set-attack-outcome. These sequences of events were assumed to be first-order Markov chains where the quality of each contact depended only on the quality of the previous contact but not explicitly on contacts further removed in the sequence. We represented these sequences in …

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Front Matter, Vol. 68 No. 1 Mar 2008

Front Matter, Vol. 68 No. 1

Western North American Naturalist

No abstract provided.

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A Tool To Support Ontology Creation Based On Incremental Mini-Ontology Merging, Zonghui Lian Mar 2008

A Tool To Support Ontology Creation Based On Incremental Mini-Ontology Merging, Zonghui Lian

Theses and Dissertations

This thesis addresses the problem of tool support for semi-automatic ontology mapping and merging. Solving this problem contributes to ontology creation and evolution by relieving users from tedious and time-consuming work. This thesis shows that a tool can be built that will take a “mini-ontology” and a “growing ontology” as input and make it possible to produce manually, semi-automatically, or automatically an extended growing ontology as output. Characteristics of this tool include: (1) a graphical, interactive user interface with features that will allow users to map and merge ontologies, and (2) a framework supporting pluggable, semi-automatic, and automatic mapping and …

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The Role Of Perceptions Of Female Administrators Regarding The Gender Regimes In Urban Co-Educational Secondary Schools In Uganda, Frances Naluwemba Mar 2008

The Role Of Perceptions Of Female Administrators Regarding The Gender Regimes In Urban Co-Educational Secondary Schools In Uganda, Frances Naluwemba

Theses and Dissertations

Leaders and policy makers in Uganda developed a national strategy of placing female administrators in traditionally male-dominated coeducational secondary schools in the belief that their vision would promote equitable education by changing gender regimes that play in schools. Gender regimes are patterns of gender arrangements that could disadvantage the education of boys or girls (Connell, 2002). The purpose of this study was to discover if female administrators perceived and had developed strategies to change gender regimes in their schools. Participants were 13 female administrators of government-supported coeducational mixed/day secondary schools in Kampala and Wakiso urban districts. Participants ranged in age …

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Automated Quadrilateral Coarsening By Ring Collapse, Mark William Dewey Mar 2008

Automated Quadrilateral Coarsening By Ring Collapse, Mark William Dewey

Theses and Dissertations

In most finite element analysis, a uniform mesh is not the optimum way to model the problem. Mesh adaptation is the ability to modify a finite element model to include regions of the mesh with higher and lower node density. Mesh adaptation has received extensive study in both computational mechanics and computer graphics to increase the resolution or accuracy of the solution in specific areas. The algorithm developed in this thesis, the Automated Quadrilateral Coarsening by Ring Collapse (AQCRC) algorithm, provides a unique solution to allow conformal coarsening of both structured and unstructured quadrilateral finite element meshes. The algorithm is …

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Liquefaction Mitigation Using Vertical Composite Drains And Liquefaction Induced Downdrag On Piles: Implications For Deep Foundation Design, Spencer R. Strand Mar 2008

Liquefaction Mitigation Using Vertical Composite Drains And Liquefaction Induced Downdrag On Piles: Implications For Deep Foundation Design, Spencer R. Strand

Theses and Dissertations

Deep foundations constructed in liquefiable soils require specialized design. The design engineer of such foundations must consider the effects of liquefaction on the foundation and overlying structure, such as excessive settlement, loss of skin friction at the soil-pile interface, and the development of downdrag on the pile. Controlled blasting was employed to liquefy a loose, saturated sand in order to test the liquefaction prevention capabilities of full-scale, vertical composite earthquake (EQ) drains and to investigate the development of downdrag on full-scale test piles. Blasting produced liquefaction at a test site without EQ drains which eventually resulted in 270 mm of …

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Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan Mar 2008

Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan

Faculty Publications

Exact results in any field, including statistical mechanics, are both aesthetically pleasing and very valuable in assessing theoretical approximations.

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The Neglect Of Divorce In Marital Research: An Ontological Analysis Of The Work Of John Gottman, Joseph Andrew Ostenson Mar 2008

The Neglect Of Divorce In Marital Research: An Ontological Analysis Of The Work Of John Gottman, Joseph Andrew Ostenson

Theses and Dissertations

This thesis explores why the divorce rate has remained relatively stable over the past few decades, even in the face of rapidly growing social sciences – particularly the branch associated with the study and treatment of marriage – through an analysis of the work of John Gottman. This thesis chiefly claims that divorce is not addressed in marital research. It is argued, however, that far from being intentional on the part of researchers, the disregard for divorce in the marital research is actually due to underlying, unrecognized assumptions. Specifically, this thesis analyzes the most fundamental assumptions – the ontological assumptions …

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Improving Liquid State Machines Through Iterative Refinement Of The Reservoir, R David Norton Mar 2008

Improving Liquid State Machines Through Iterative Refinement Of The Reservoir, R David Norton

Theses and Dissertations

Liquid State Machines (LSMs) exploit the power of recurrent spiking neural networks (SNNs) without training the SNN. Instead, a reservoir, or liquid, is randomly created which acts as a filter for a readout function. We develop three methods for iteratively refining a randomly generated liquid to create a more effective one. First, we apply Hebbian learning to LSMs by building the liquid with spike-time dependant plasticity (STDP) synapses. Second, we create an eligibility based reinforcement learning algorithm for synaptic development. Third, we apply principles of Hebbian learning and reinforcement learning to create a new algorithm called separation driven synaptic modification …

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Satisficing Theory And Non-Cooperative Games, Matthew S. Nokleby Mar 2008

Satisficing Theory And Non-Cooperative Games, Matthew S. Nokleby

Theses and Dissertations

Satisficing game theory is an alternative to traditional non-cooperative game theory which offers increased flexibility in modeling players' social interactions. However, satisficing players with conflicting attitudes may implement dysfunctional behaviors, leading to poor performance. In this thesis, we present two attempts to "bridge the gap" between satisficing and non-cooperative game theory. First, we present an evolutionary method by which players adapt their attitudes to increase raw payoff, allowing players to overcome dysfunction. We extend the Nash equilibrium concept to satisficing games, showing that the evolutionary method presented leads the players toward an equilibrium in their attitudes. Second, we introduce the …

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Compiling And Annotating A Syriac Corpus, George Busby, James Carroll, Marc Carmen, Carl Griffin, Robbie Haertel, Kristian Heal, Joshua Heaton, Deryle W. Lonsdale, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi, David Taylor Mar 2008

Compiling And Annotating A Syriac Corpus, George Busby, James Carroll, Marc Carmen, Carl Griffin, Robbie Haertel, Kristian Heal, Joshua Heaton, Deryle W. Lonsdale, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi, David Taylor

Faculty Publications

PDF of Powerpoint Presentation on compiling and annotating a Syriac corpus. This presentation was given at the Conference of the American Association for Corpus Linguistics in 2008.

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Accelerating Corpus Annotation Through Active Learning, George Busby, Marc Carmen, James Carroll, Robbie Haertel, Deryle W. Lonsdale, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi Mar 2008

Accelerating Corpus Annotation Through Active Learning, George Busby, Marc Carmen, James Carroll, Robbie Haertel, Deryle W. Lonsdale, Peter Mcclanahan, Eric K. Ringger, Kevin Seppi

Faculty Publications

PDF of Powerpoint Presentation on accelerating corpus annotation through active learning. This presentation was given at the Conference of the American Association for Corpus Linguistics in 2008.

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Analysis Of Canonical Chinese Antonym Co-Occurrence, Eric K. Ringger, Guohui Liu, Shiping Liu, Xingfu Wang Mar 2008

Analysis Of Canonical Chinese Antonym Co-Occurrence, Eric K. Ringger, Guohui Liu, Shiping Liu, Xingfu Wang

Faculty Publications

PDF of Powerpoint Presentation on canonical Chinese antonym co-occurrence. This presentation was given at the Conference of the American Association for Corpus Linguistics in 2008.

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