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Cluster And Classification Analysis Of Fossil Invertebrates Within The Bird Spring Formation, Arrow Canyon, Nevada: Implications For Relative Rise And Fall Of Sea-Level, Scott L. Morris Apr 2010

Cluster And Classification Analysis Of Fossil Invertebrates Within The Bird Spring Formation, Arrow Canyon, Nevada: Implications For Relative Rise And Fall Of Sea-Level, Scott L. Morris

Theses and Dissertations

Carbonate strata preserve indicators of local marine environments through time. Such indicators often include microfossils that have relatively unique conditions under which they can survive, including light, nutrients, salinity, and especially water temperature. As such, microfossils are environmental proxies. When these microfossils are preserved in the rock record, they constitute key components of depositional facies. Spence et al. (2004, 2007) has proposed several approaches for determining the facies of a given stratigraphic succession based upon these proxies. Cluster analysis can be used to determine microfossil groups that represent specific environmental conditions. Identifying which microfossil groups exist through time can indicate …

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Automatic Transition To Peer-To-Peer Download, Roger D. Pack Apr 2010

Automatic Transition To Peer-To-Peer Download, Roger D. Pack

Theses and Dissertations

For traditional web servers, available bandwidth decreases as the number of clients increases. This can cause servers to serve files slowly or to become completely overwhelmed when load grows too high. BitTorrent is a peer-to-peer solution to this problem, but it requires manual configuration for each file to be delivered this way. We develop a new system that integrates peer-to-peer file delivery with traditional client-server downloads. Clients initially attempt to download a file from a web server; if this is too slow, they transition to peer-to-peer delivery. Experiments with a prototype system show that it serves up to 30x faster …

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A Design Framework That Employs A Classification Scheme And Library For Compliant Mechanism Design, Brian Mark Olsen Apr 2010

A Design Framework That Employs A Classification Scheme And Library For Compliant Mechanism Design, Brian Mark Olsen

Theses and Dissertations

Limited resources are currently available to assist engineers in implementing compliant members into mechanical designs. As a result, engineers often have little to no direction incorporating compliant mechanisms. This thesis develops a conceptual design framework and process that utilizes a proposed classification scheme and a library of mechanisms to help engineers incorporate compliant mechanisms into their applications. As the knowledge related to the synthesis and analysis of compliant mechanisms continues to grow and mature, and through the classification scheme established in this thesis, compliant mechanisms may become more extensively used in commercial mechanical designs. This thesis also demonstrates a design …

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Field Evaluation Of Asphalt Overlays On State Route 30 In Northern Utah, Mark J. Butler Apr 2010

Field Evaluation Of Asphalt Overlays On State Route 30 In Northern Utah, Mark J. Butler

Theses and Dissertations

The purpose of this research was to compare the rutting, cracking, and development of roughness of two asphalt overlay types commonly used in northern Utah and to evaluate how well the Mechanistic-Empirical Pavement Design Guide (MEPDG) can predict the observed results. AC-10 and PG 64-34 asphalt overlay materials were paved in a checkerboard pattern at a test site on State Route 30 near Logan, Utah, and observed for 3 years at 6-month intervals. Primary data included rutting, cracking, and roughness. At the conclusion of the 3-year evaluation period, rut depths were 0.08 in. deeper, on average, in the AC-10 overlay …

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Ribosomal Rna Mutations That Inhibit The Activity Of Transfer-Messenger Rna Of Stalled Ribosomes, Jacob N. Crandall Apr 2010

Ribosomal Rna Mutations That Inhibit The Activity Of Transfer-Messenger Rna Of Stalled Ribosomes, Jacob N. Crandall

Theses and Dissertations

In eubacteria, stalled ribosomes are rescued by a conserved quality-control mechanism involving transfer-messenger RNA (tmRNA) and its protein partner SmpB. Mimicking a tRNA, tmRNA enters stalled ribosomes, adds Ala to the nascent polypeptide, and serves as a template to encode a short peptide that tags the nascent protein for destruction. To further characterize the tagging process, we developed two genetic selections that link tmRNA activity to cell death. These negative selections can be used to identify inhibitors of tagging or to identify mutations in key residues essential for ribosome rescue. Little is known about which ribosomal elements are specifically required …

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Front Matter, Vol. 70 No. 1 Apr 2010

Front Matter, Vol. 70 No. 1

Western North American Naturalist

No abstract provided.

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Large-Scale Effects On Bird Assemblages In Desert Grasslands, Giselle Block, Michael L. Morrison Apr 2010

Large-Scale Effects On Bird Assemblages In Desert Grasslands, Giselle Block, Michael L. Morrison

Western North American Naturalist

During winter 1996–1997 and summer 1997, we surveyed birds at 26 study sites in desert grasslands of Arizona and New Mexico to determine tolerance of birds to variability in plant composition and structure. The relationship between bird abundance and vegetative characteristics might be an important consideration in the development of management and restoration plans. Of the 49 bird species we observed, we examined 13 and 16 species in detail for winter and summer seasons, respectively. A noticeable shift in species composition occurred between 3% and 10% woody plant cover. During winter, Chestnut-collared Longspurs (Calcarius ornatus) and Horned Larks …

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Secret Key Establishment Using Wireless Channels As Common Randomness In Time-Variant Mimo Systems, Chan Chen Apr 2010

Secret Key Establishment Using Wireless Channels As Common Randomness In Time-Variant Mimo Systems, Chan Chen

Theses and Dissertations

Encryption of confidential data with a secret key has become a widespread technique for securing wireless transmissions. However, existing key distribution methods that either deliver the secret key with a key distribution center or exchange the secret key using public-key cryptosystems are unable to establish perfect secret keys necessary for symmetric encryption techniques. This research considers secret key establishment, under the broad research area of information theoretic security, using the reciprocal wireless channel as common randomness for the extraction of perfect secret keys in multiple-input multiple-output (MIMO)communication systems. The presentation discusses the fundamental characteristics of the time-variant MIMO wireless channel …

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Signal Processing Methods For Ultra-High Resolution Scatterometry, Brent A. Williams Apr 2010

Signal Processing Methods For Ultra-High Resolution Scatterometry, Brent A. Williams

Theses and Dissertations

This dissertation approaches high resolution scatterometry from a new perspective. Three related general topics are addressed: high resolution σ^0 imaging, wind estimation from high resolution σ^0 images over the ocean, and high resolution wind estimation directly from the scatterometer measurements. Theories of each topic are developed, and previous approaches are generalized and formalized. Improved processing algorithms for these theories are developed, implemented for particular scatterometers, and analyzed. Specific results and contributions are noted below. The σ^0 imaging problem is approached as the inversion of a noisy aperture-filtered sampling operation-extending the current theory to deal explicitly with noise. A maximum aposteriori …

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Andrew Targowski, Information Technology And Societal Development, William Mcgaughey Apr 2010

Andrew Targowski, Information Technology And Societal Development, William Mcgaughey

Comparative Civilizations Review

No abstract provided.

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Full Issue, Byu Studies Apr 2010

Full Issue, Byu Studies

BYU Studies

No abstract provided.

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Effects Of Relationship Status On Gpa, Emily Albright, Chanel Carlile, Janae Kirkendall, Allyson Webber Apr 2010

Effects Of Relationship Status On Gpa, Emily Albright, Chanel Carlile, Janae Kirkendall, Allyson Webber

FHSS Mentored Research Conference

Research on the effect of Relationship Status on GPA is very limited. Some studies find that individuals who date more frequently tend to have lower grades than those who don’t. Other studies have found that relationships can have a positive or a negative effect on GPA depending on other factors. However, most studies find that Relationship status doesn’t have an effect on GPA. We hypothesize that Single and Married individuals will have higher GPA’s than their dating counterparts. We further hypothesize that Single and Married people will also be more consistent in their academic achievement and that those who are …

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The Influence Of Spengler And Toynbee On Joseph Campbell (And Vice Versa?), T. Reed Smith Apr 2010

The Influence Of Spengler And Toynbee On Joseph Campbell (And Vice Versa?), T. Reed Smith

Comparative Civilizations Review

No abstract provided.

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End Matter, Comparative Civilizations Review Apr 2010

End Matter, Comparative Civilizations Review

Comparative Civilizations Review

No abstract provided.

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Paradox And Discipleship, Terry L. Givens Apr 2010

Paradox And Discipleship, Terry L. Givens

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.

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Egyptian Papyri And The Book Of Abraham: Some Questions And Answers, Kerry Muhlestein Apr 2010

Egyptian Papyri And The Book Of Abraham: Some Questions And Answers, Kerry Muhlestein

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.

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Faith And Inquiry, Justin F. White Apr 2010

Faith And Inquiry, Justin F. White

BYU Studies

My wife's uncle recently, and somewhat smugly, said something to the effect, "It's too bad you're studying philosophy (or perhaps any subject) at BYU since you only get one perspective." For the most part, I've found this is simply not true. I've found professors and students not nearly as homogeneous as often portrayed. Though I agree with my wife's uncle that we should engage in dialogue with those of differing opinions, since there are, of course, disadvantages when only a single perspective is represented on a topic, I'd like to focus on one potential positive interpretation of the sameness he …

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Multiple Intelligences In The Gospel Classroom, John Hilton Iii Apr 2010

Multiple Intelligences In The Gospel Classroom, John Hilton Iii

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.

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Structure-Property Maps And Optimal Inversion In Configurational Thermodynamics, Gus L. W. Hart, Björn Arnold, Alejandro Díaz Ortiz, Helmut Dosch Mar 2010

Structure-Property Maps And Optimal Inversion In Configurational Thermodynamics, Gus L. W. Hart, Björn Arnold, Alejandro Díaz Ortiz, Helmut Dosch

Faculty Publications

Cluster expansions of first-principles density-functional databases in multicomponent systems are now used as a routine tool for the prediction of zero- and finite-temperature physical properties. The ability of producing large databases of various degrees of accuracy, i.e., high-throughput calculations, makes pertinent the analysis of error propagation during the inversion process. This is a very demanding task as both data and numerical noise have to be treated on equal footing. We have addressed this problem by using an analysis that combines the variational and evolutionary approaches to cluster expansions. Simulated databases were constructed ex professo to sample the configurational space in …

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Formant Changes In Amateur Singers After Instruction In A Vowel Equalization Technique, Emily Mullins Heaton Mar 2010

Formant Changes In Amateur Singers After Instruction In A Vowel Equalization Technique, Emily Mullins Heaton

Theses and Dissertations

Vowel equalization is a technique that can be used by singers to achieve a more balanced vocal tone. The technique balances corresponding front and back vowels, which share approximate tongue heights, and also balances high and low vowels in a more neutral or centralized lingual posture. Formants are resonance peaks that define each specific vowel. This study measured shifts in the first and second formants (F1 and F2) of the vowels /e, i, ɑ, o, u/ following training in vowel equalization. Prior to the training, the vowel formants were measured in amateur 15 college-aged singers. They sang the first two …

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The Effects Of Video Self-Modeling On Elementary Students' On-Task Behavior As A Response To Intervention, Anika Kronmiller Bales Mar 2010

The Effects Of Video Self-Modeling On Elementary Students' On-Task Behavior As A Response To Intervention, Anika Kronmiller Bales

Theses and Dissertations

Effective interventions are imperative for students who are at-risk for academic failure. Response to Intervention (RTI), a service delivery framework, is gaining momentum in schools as it aims to provide effective and appropriate interventions of varying degrees. Frequently used in the form of a three-tier process, RTI addresses academic and behavioral deficits for students first at a school-wide level; next, at an individualized level; and finally, at a more intense individualized level. This study examined the effects of video self-modeling (VSM) as a Tier 2 RTI for two students in general education classrooms. Both students exhibited low rates of on-task …

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Syngas Fermentation: Quantification Of Assay Techniques, Reaction Kinetics, And Pressure Dependencies Of The Clostridial P11 Hydrogenase, Bradley E. Skidmore Mar 2010

Syngas Fermentation: Quantification Of Assay Techniques, Reaction Kinetics, And Pressure Dependencies Of The Clostridial P11 Hydrogenase, Bradley E. Skidmore

Theses and Dissertations

Ethanol usage as a transportation fuel is rapidly increasing in the United States. Production of ethanol from cellulose feedstocks via gasification followed by syngas fermentation offers an environmentally friendly approach that mitigates many of the adverse effects associated with production from corn. In the syngas fermentation process, the hydrogenase enzyme of the fermentation bacterium, Clostridium P11 for this work, supplies electrons to the metabolic pathway, facilitating ethanol production. In this thesis, an assay for P11 hydrogenase activity was developed. It was determined that 1) less than 4 minutes of sparging with 50 sccm H2 is needed to reduce O2 levels …

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Turning Points: Stories Of How Students Get Beyond Antipathy Toward An Academic Course, Cheryl Lynn Morse Mar 2010

Turning Points: Stories Of How Students Get Beyond Antipathy Toward An Academic Course, Cheryl Lynn Morse

Theses and Dissertations

The purpose of this qualitative study was to examine the narratives of 10 students who began an academic course with strong negative attitudes but finished the course with strong positive attitudes. In the beginning of the course, each student exhibited one of these three tendencies: apathetic, compliant, or disillusioned; however, by the end of the course, they exhibited a transformed disposition. This study attempts to answer the question of what the turning points were for their transformation and how they made the change. The findings of this study were that regardless of individual tendencies, the ability to exercise agency was …

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Processing A Nickel Nanostrand And Nickel Coated Carbon Fiber Filled Conductive Polyethylene By Injection Molding, David Anthony Whitworth Mar 2010

Processing A Nickel Nanostrand And Nickel Coated Carbon Fiber Filled Conductive Polyethylene By Injection Molding, David Anthony Whitworth

Theses and Dissertations

A new method for pre-impregnating nickel coated carbon fiber with a thermoplastic polymer to make towpreg, similar to a recently developed coating-line by João P. Nunes et al and a new electrically conductive thermoplastic are developed. A melted bath was used to help mitigate health concerns and waste for dispersion of nickel coated carbon fibers (NCF) in low density polyethylene (LDPE). This towpreg was then mixed with more LDPE or a mixture of LDPE and nickel nanostrands (NiNS) to a desired filler volume fraction to test the electrical conductivity of the composite. Some of these mixtures were then injection molded …

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Development And Use Of Microsatellite Markers For Genetic Diversity Analysis Of Canahua (Chenopodium Pallidicaule Aellen), Amalia Vargas Mar 2010

Development And Use Of Microsatellite Markers For Genetic Diversity Analysis Of Canahua (Chenopodium Pallidicaule Aellen), Amalia Vargas

Theses and Dissertations

Cañahua (Chenopodium pallidicaule Aellen) is a poorly studied, annual subsistence crop of the high Andes of South America. Its nutritionally value (high in protein and mineral content) and ability to thrive in harsh climates (drought, extreme elevations, etc.) make it an important regional food crop throughout the Andean region. The objectives of this study were to develop genetic markers and to quantify genetic diversity within cañahua. A set of 43 wild and cultivated cañahua genotypes and two related species (C. quinoa and C. petiolare) were evaluated for polymorphism using 192 microsatellite markers derived from random genomic …

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Optimal Design Of A Planar 3-Rpr Haptic Interface Based On Manipulability, Wesley Kay Harris Mar 2010

Optimal Design Of A Planar 3-Rpr Haptic Interface Based On Manipulability, Wesley Kay Harris

Theses and Dissertations

A haptic interface is a robotic force feedback device that provides a sense of touch to users of virtual reality simulations. This thesis presents a general method for the design optimization of parallel planar haptic devices based on maximizing the manipulability of the interface over its workspace. Manipulability is selected as the key design objective to ensure avoidance of singular configurations within the workspace and to maximize the interface's ability to generate feedback forces and torques in each direction in each handle location and orientation. The optimization approach developed in this thesis results in a set of candidate designs that …

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Extensions Of Nearest Shrunken Centroid Method For Classification, Tomohiko Funai Mar 2010

Extensions Of Nearest Shrunken Centroid Method For Classification, Tomohiko Funai

Theses and Dissertations

Stylometry assumes that the essence of the individual style of an author can be captured using a number of quantitative criteria, such as the relative frequencies of noncontextual words (e.g., or, the, and, etc.). Several statistical methodologies have been developed for authorship analysis. Jockers et al. (2009) utilize Nearest Shrunken Centroid (NSC) classification, a promising classification methodology in DNA microarray analysis for authorship analysis of the Book of Mormon. Schaalje et al. (2010) develop an extended NSC classification to remedy the problem of a missing author. Dabney (2005) and Koppel et al. (2009) suggest other modifications of NSC. This paper …

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Applications Of Descriptive Set Theory In Homotopy Theory, Samuel M. Corson Mar 2010

Applications Of Descriptive Set Theory In Homotopy Theory, Samuel M. Corson

Theses and Dissertations

This thesis presents new theorems in homotopy theory, in particular it generalizes a theorem of Saharon Shelah. We employ a technique used by Janusz Pawlikowski to show that certain Peano continua have a least nontrivial homotopy group that is finitely presented or of cardinality continuum. We also use this technique to give some relative consistency results.

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The Role Of Algorithmic Decision Processes In Decision Automation: Three Case Studies, Blake Edward Durtschi Mar 2010

The Role Of Algorithmic Decision Processes In Decision Automation: Three Case Studies, Blake Edward Durtschi

Theses and Dissertations

This thesis develops a new abstraction for solving problems in decision automation. Decision automation is the process of creating algorithms which use data to make decisions without the need for human intervention. In this abstraction, four key ideas/problems are highlighted which must be considered when solving any decision problem. These four problems are the decision problem, the learning problem, the model reduction problem, and the verification problem. One of the benefits of this abstraction is that a wide range of decision problems from many different areas can be broken down into these four “key” sub-problems. By focusing on these key …

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Diversity And Abundance Of The Dark Kangaroo Mouse, Microdipodops Megacephalus, In Communities Of Nocturnal Granivorous Rodents In Western North America, Ashley Sagers Haug Mar 2010

Diversity And Abundance Of The Dark Kangaroo Mouse, Microdipodops Megacephalus, In Communities Of Nocturnal Granivorous Rodents In Western North America, Ashley Sagers Haug

Theses and Dissertations

The dark kangaroo mouse, Microdipodops megacephalus, is a sensitive species in the Great Basin Desert. This thesis explores the structure of desert rodent communities of the Great Basin to better understand M. megacephalus' place in the community and the conditions that promote large and stable populations. To determine community structure, I used nestedness analysis to evaluate 99 communities of nocturnal granivorous rodents. I found that the community structure was non-random, indicating the existence of assembly rules and ecological constraints. I also found that M. megacephalus was the second most vulnerable species in the community. To explore the correlation …

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