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Articles 1321 - 1350 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich Dec 2013

Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich

Theses and Dissertations

Although phylloid algal mounds have been studied for 50 year, much remains to be determined concerning the ecology and sedimentology of these Late Paleozoic carbonate buildups. Herein we perform a digital outcrop study of the well-known Middle Pennsylvanian Lower Ismay mound interval in the Paradox Basin because outcropping mounds along the San Juan River are cited as outcrop analogs of reservoir carbonates in the Paradox Basin oil province of Utah and adjacent states. The principal field area is the Eight Foot algal field located at river mile 19.2 on the San Juan River, approximately 14 miles SSW of Bluff, Utah. …

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Minimum Rank Problems For Cographs, Nicole Andrea Malloy Dec 2013

Minimum Rank Problems For Cographs, Nicole Andrea Malloy

Theses and Dissertations

Let G be a simple graph on n vertices, and let S(G) be the class of all real-valued symmetric nxn matrices whose nonzero off-diagonal entries occur in exactly the positions corresponding to the edges of G. The smallest rank achieved by a matrix in S(G) is called the minimum rank of G, denoted mr(G). The maximum nullity achieved by a matrix in S(G) is denoted M(G). For each graph G, there is an associated minimum rank class, MR(G) consisting of all matrices A in S(G) with rank A = mr(G). Although no restrictions are applied to the diagonal entries of …

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Formation And Analysis Of Zinc Oxide Nanoparticles And Zinc Oxide Hexagonal Prisms And Optical Analysis Of Cadmium Selenide Nanoparticles, Jared M. Hancock Dec 2013

Formation And Analysis Of Zinc Oxide Nanoparticles And Zinc Oxide Hexagonal Prisms And Optical Analysis Of Cadmium Selenide Nanoparticles, Jared M. Hancock

Theses and Dissertations

In this dissertation, methods to synthesize ZnO are reported. First, zinc oxide nanoparticles were synthesized with small amounts of transition metal ions to create materials called dilute magnetic semiconductors (DMS). We employed a low temperature sol-gel method that produces ZnO nanoparticles of reproducible size and incorporates cobalt, nickel, and manganese ions into the nanoparticles. Conditions were controlled such that a range of amounts of Co, Ni, and Mn were incorporated. The incorporation was tracked by color changes in the white ZnO powder to blue for Co, green for Ni and yellow for Mn. XRD measurements showed the nanoparticles were on …

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Obstacles And Solutions To Studying Functional Adhesives Using Vibrational Sum-Frequency Generation Spectroscopy, Angela Renee Andersen Dec 2013

Obstacles And Solutions To Studying Functional Adhesives Using Vibrational Sum-Frequency Generation Spectroscopy, Angela Renee Andersen

Theses and Dissertations

Important aspects of adhesion occur at interfaces, including structures that may be different from those in the bulk materials. However, probing the orientation of molecules in functional adhesives poses a significant challenge because adhesive molecules are always located at a buried interface. The limited penetration depth of surface-specific analysis prohibits the study of buried interfaces using those techniques. The large quantity of bulk molecules relative to the adhesive molecules interacting at the interface results in the bulk signal swamping out adhesive signal in bulk analysis techniques. An interface-specific technique is required to study functional adhesives. One such technique that has …

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Shaping Swarms Through Coordinated Mediation, Shin-Young Jung Dec 2013

Shaping Swarms Through Coordinated Mediation, Shin-Young Jung

Theses and Dissertations

A swarm is a group of uninformed individuals that exhibit collective behaviors. Without any information about the external world, a swarm has limited ability to achieve complex goals. Prior work on human-swarm interaction methods allow a human to influence these uninformed individuals through either leadership or predation as informed agents that directly interact with humans. These methods of influence have two main limitations: (1) although leaders sustain influence over nominal agents for a long period of time, they tend to cause all collective structures to turn in to flocks (negating the benefit of other swarm formations) and (2) predators tend …

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Investigation Into The Effects Of Pegylation On The Thermodynamic Stability Of The Ww Domain, Sam S. Matthews Dec 2013

Investigation Into The Effects Of Pegylation On The Thermodynamic Stability Of The Ww Domain, Sam S. Matthews

Theses and Dissertations

The covalent attachment of poly(ethylene glycol) (PEG) to a protein surface (known as PEGylation), has been demonstrated to increase the serum half-life of therapeutic proteins by reducing kidney clearance and immunogenicity and by protecting against proteolysis. Theses beneficial effects could be further enhanced if PEGylation consistently increased protein conformational stability (i.e. the difference in free energy between the folded and unfolded states). However, the effects of PEGylation on protein conformational stability are unpredictable; PEGylation has been reported to increase, decrease, or have no effect on the conformational stability of medicinal proteins.This thesis details the results of two studies aimed at …

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Ferritin-Based Photo-Oxidation Of Biomass For Nanoparticle Synthesis, Bioremediation, And Hydrogen Evolution, Oscar Petrucci Dec 2013

Ferritin-Based Photo-Oxidation Of Biomass For Nanoparticle Synthesis, Bioremediation, And Hydrogen Evolution, Oscar Petrucci

Theses and Dissertations

The cell is the basic unit of all living organisms. It is an amazing machine capable of self-replicating, growing, and synthesizing and shuttling thousands of compounds. To perform all of these activities the cell needs energy. The original source of energy for all living beings is the Sun. The energy of the sun is collected by the autotrophs (mostly plants) through photosynthesis and stored in the chemical bonds of carbohydrates and lipids through carboxylic acid intermediates; animals use these compounds to obtain the energy for their cells. Most of the energy extracted by the cell comes from the citric acid …

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The Pseudo-Rigid-Body Model For Fast, Accurate, Non-Linear Elasticity, Anthony R. Hall Nov 2013

The Pseudo-Rigid-Body Model For Fast, Accurate, Non-Linear Elasticity, Anthony R. Hall

Theses and Dissertations

We introduce to computer graphics the Pseudo-Rigid-Body Mechanism (PRBM) and the chain algorithm from mechanical engineering, with a unified tutorial from disparate source materials. The PRBM has been used successfully to simplify the simulation of non-linearly elastic beams, using deflections of an analogous spring and rigid-body linkage. It offers computational efficiency as well as an automatic parameterization in terms of physically measurable, intuitive inputs which fit naturally into existing animation work flows for character articulation. The chain algorithm is a technique for simulating the deflection of complicated elastic bodies in terms of straight elastic elements, which has recently been extended …

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A Topics Analysis Model For Health Insurance Claims, Jared Anthony Webb Oct 2013

A Topics Analysis Model For Health Insurance Claims, Jared Anthony Webb

Theses and Dissertations

Mathematical probability has a rich theory and powerful applications. Of particular note is the Markov chain Monte Carlo (MCMC) method for sampling from high dimensional distributions that may not admit a naive analysis. We develop the theory of the MCMC method from first principles and prove its relevance. We also define a Bayesian hierarchical model for generating data. By understanding how data are generated we may infer hidden structure about these models. We use a specific MCMC method called a Gibbs' sampler to discover topic distributions in a hierarchical Bayesian model called Topics Over Time. We propose an innovative use …

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Size-Based Separation Of Bioparticles Using Planar Nanofluidic Devices, Jie Xuan Sep 2013

Size-Based Separation Of Bioparticles Using Planar Nanofluidic Devices, Jie Xuan

Theses and Dissertations

Nanofluidic devices are structures having at least one dimension in the submicron range, which is of the same order of magnitude as the sizes of biomolecules and bioparticles such as proteins and viruses. As a result, size-selective separations are important applications for nanofluidics. Well-defined micro or nano device structures fabricated via micromachining have greatly reduced sample consumption and enabled separations in a parallel fashion, promising significant speed and resolution advantages over conventional size separation techniques, such as gel electrophoresis and size exclusion chromatography. In collaboration with others, I have developed a size separation method using nanofluidic devices consisting of an …

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Sensor-Driven Hierarchical Path Planning For Unmanned Aerial Vehicles Using Canonical Tasks And Sensors, Spencer James Clark Sep 2013

Sensor-Driven Hierarchical Path Planning For Unmanned Aerial Vehicles Using Canonical Tasks And Sensors, Spencer James Clark

Theses and Dissertations

Unmanned Aerial Vehicles (UAVs) are increasingly becoming economical platforms for carrying a variety of sensors. Building flight plans that place sensors properly, temporally and spatially, is difficult. The goal of sensor-driven planning is to automatically generate flight plans based on desired sensor placement and temporal constraints. We propose a simple taxonomy of UAV-enabled sensors, identify a set of generic sensor tasks, and argue that many real-world tasks can be represented by the taxonomy. We present a hierarchical sensor-driven flight planning system capable of generating 2D flights that satisfy desired sensor placement and complex timing and dependency constraints. The system makes …

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Formation, Functionalization, Characterization, And Applications Of A Mixed-Mode, Carbon/Diamond-Based, Core-Shell Phase For High Performance Liquid Chromatography, Landon A. Wiest Sep 2013

Formation, Functionalization, Characterization, And Applications Of A Mixed-Mode, Carbon/Diamond-Based, Core-Shell Phase For High Performance Liquid Chromatography, Landon A. Wiest

Theses and Dissertations

My work has focused on a variety of different types of diamond-based, core-shell particles. These particles are formed with inert cores and poly(allylamine)/nanodiamond shells. Their intended purpose is to form an LC stationary phase that is stable from pH 1 – 14 and at elevated temperatures. At the beginning of my studies, the particles that had been made in the Linford laboratory were pH stable, but irregular and had poor mechanical stability. Since that time, I have worked to improve the particles by using more spherical zirconia and carbon cores, and I have improved their mechanical stability via chemical crosslinking …

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Self-Assembled Dna Origami Templates For The Fabrication Of Electronic Nanostructures, Elisabeth Pound Gates Sep 2013

Self-Assembled Dna Origami Templates For The Fabrication Of Electronic Nanostructures, Elisabeth Pound Gates

Theses and Dissertations

An important goal of nanoscience is the self-assembly of nanoscale building blocks into complex nanostructures. DNA is an important and versatile building block for nanostructures because of its small size, predictable base pairing, and numerous sequence possibilities. I use DNA origami to design and fold DNA into predesigned shapes, to assemble thin, branched DNA nanostructures as templates for nanoscale metal features. Using a PCR-based scaffold strand generation procedure, several wire-like nanostructures with varying scaffold lengths were assembled. In addition, more complex prototype circuit element structures were designed and assembled, demonstrating the utility of this technique in creating complex templates. My …

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Human-Swarm Interaction: Effects On Operator Workload, Scale, And Swarm Topology, Brian O. Pendleton Sep 2013

Human-Swarm Interaction: Effects On Operator Workload, Scale, And Swarm Topology, Brian O. Pendleton

Theses and Dissertations

Robots, including UAVs, have found increasing use in helping humans with dangerous and difficult tasks. The number of robots in use is increasing and is likely to continue increasing in the future. As the number of robots increases, human operators will need to coordinate and control the actions of large teams of robots. While multi-robot supervisory control has been widely studied, it requires that an operator divide his or her attention between robots. Consequently, the use of multi-robot supervisory control is limited by the number of robots that a human or team of humans can reasonably control. Swarm robotics -- …

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Distributed Agent Cloud-Sourced Malware Reporting Framework, Kellie Elizabeth Kercher Sep 2013

Distributed Agent Cloud-Sourced Malware Reporting Framework, Kellie Elizabeth Kercher

Theses and Dissertations

Malware is a fast growing threat that consists of a malicious script or piece of software that is used to disrupt the integrity of a user's experience. Antivirus software can help protect a user against these threats and there are numerous vendors users can choose from for their antivirus protection. However, each vendor has their own set of virus definitions varying in resources and capabilities in recognizing new threats. Currently, a persistent system is not in place that measures and displays data on the performance of antivirus vendors in responding to new malware over a continuous period of time. There …

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A Bond Valence-Based Force Field: A Multi-Body Approach, Matthew Harris Davis Aug 2013

A Bond Valence-Based Force Field: A Multi-Body Approach, Matthew Harris Davis

Theses and Dissertations

The typical form for a molecular mechanics force field consists of a foundation of pair-wise terms to describe bonded and non-bonded atomic interactions, with multi-body correction terms to deal with the limitations of pair-wise terms. I present here the first attempts of a molecular mechanics model that is founded on multi-body terms, which are based on the Bond Valence Model (Brown, 2002) and recent developments in the Vectorial Bond Valence Model (Bickmore et al., 2013a; Harvey et al., 2006). I calibrated these models on pressure vs. energy curves for a set of SiO2 polymorphs. The average deviation for the best-fit …

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Annotated Chromatographic Isotope Features From A Highly Complex Mass Spectrometry Proteomic Dataset (Mouse) For Feature Detection Algorithm Evaluation, John T. Prince, Christoper Conley Aug 2013

Annotated Chromatographic Isotope Features From A Highly Complex Mass Spectrometry Proteomic Dataset (Mouse) For Feature Detection Algorithm Evaluation, John T. Prince, Christoper Conley

ScholarsArchive Data

This data set and accompanying annotations, referred to as the MOUSE data set, were used for feature detection algorithm evaluation (FDAE) as described in "Massifquant: open-source Kalman filter based XC-MS feature detection". Bioinformatics. 2013. (additional citation details available after publication). Existing and future feature detection and quantitation methods designed for LC-MS are welcome to make use of the data. Since the annotation has isotopic information, users are encouraged to develop other meaningful algorithm evaluations at the isotopic-level. Finally, it serves as an example to be improved upon for future manual-annotation efforts undertaken by the XC-MS community.

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Building An Access Database For Cookstove Research, Margaret L. Weddle Aug 2013

Building An Access Database For Cookstove Research, Margaret L. Weddle

Student Works

This paper takes the reader through the thought process and actual instructions to create your own Microsoft Access database, or how to use the one provided with this paper. Also, instructions to use the HBLL resources of Compendex and RefWorks are covered. While this work was built specifically for Cookstoves research, it could be adapted to any research where you would need to maintain a record of the journal articles that you are using. It has been discovered that building a database is a time consuming and difficult work, but once done, Access provides an easy way to work with …

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Interactive Techniques Between Collaborative Handheld Devices And Wall Displays, Daniel Leon Schulte Aug 2013

Interactive Techniques Between Collaborative Handheld Devices And Wall Displays, Daniel Leon Schulte

Theses and Dissertations

Handheld device users want to work collaboratively on large wall-sized displays with other handheld device users. However, no software frameworks exist to support this type of collaborative activity. This thesis introduces a collaborative application framework that allows users to collaborate with each other across handheld devices and large wall displays. The framework is comprised of a data storage system and a set of generic interactive techniques that can be utilized by applications. The data synchronization system allows data to be synchronized across multiple handheld devices and wall displays. The interactive techniques enable users to create data items and to form …

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Practical Cost-Conscious Active Learning For Data Annotation In Annotator-Initiated Environments, Robbie A. Haertel Aug 2013

Practical Cost-Conscious Active Learning For Data Annotation In Annotator-Initiated Environments, Robbie A. Haertel

Theses and Dissertations

Many projects exist whose purpose is to augment raw data with annotations that increase the usefulness of the data. The number of these projects is rapidly growing and in the age of “big data” the amount of data to be annotated is likewise growing within each project. One common use of such data is in supervised machine learning, which requires labeled data to train a predictive model. Annotation is often a very expensive proposition, particularly for structured data. The purpose of this dissertation is to explore methods of reducing the cost of creating such data sets, including annotated text corpora.We …

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User Experience Engineering Adoption And Practice: A Longitudinal Case Study, Brady Edwin Redfearn Aug 2013

User Experience Engineering Adoption And Practice: A Longitudinal Case Study, Brady Edwin Redfearn

Theses and Dissertations

User Experience Engineering (UxE) incorporates subject areas like usability, HCI, interaction experience, interaction design, "human factors", ergonomics", cognitive psychology", behavioral psychology and psychometrics", systems engineering", [and] "computer science," (Hartson, 1998). It has been suggested that UxE will be the main success factor in organizations as we enter the "loyalty decade" of software development, where the repeat usage of a product by a single customer will be the metric of product success (Alghamdi, 2010; Law & van Schaik, 2010, p. 313; Nielsen, 2008; Van Schaik & Ling, 2011). What is relatively unknown in the current academic literature is whether existing UxE …

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Studies Toward The Synthesis Of Lyconadin A And Cranomycin, Brad M. Loertscher Jul 2013

Studies Toward The Synthesis Of Lyconadin A And Cranomycin, Brad M. Loertscher

Theses and Dissertations

Lyconadin A is a pentacyclic Lycopodium alkaloid isolated from the club moss Lycopodium companatum with anticancer activity. Our approach sought to incorporate a 7-exo–6-exo acyl radical cyclization cascade to access the bicyclo[5.4.0]undecane framework of lyconadin A. Our studies created methodology for the synthesis of 5-alkyl and 3,5-dialkyl-6-carbomethoxy-2-pyridones and sterically demanding epoxide substrates. These epoxide substrates underwent an unanticipated Payne rearrangement.Cranomycin is a potent antibiotic with antiprotozoal activity. Structurally it is a cyclopentane ring system with substitution at each carbon in the ring. Another interesting structural aspect is the existence of three contiguous quaternary stereocenters including two tertiary alcohols and a …

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Dynamic Near Field Communication Pairing For Wireless Sensor Networks, Steven Charles Cook Jul 2013

Dynamic Near Field Communication Pairing For Wireless Sensor Networks, Steven Charles Cook

Theses and Dissertations

Wireless sensor network (WSN) nodes communicate securely using pre-installed cryptographic keys. Although key pre-installation makes nodes less expensive, the technical process of installing keys prevents average users from deploying and controlling their own WSNs. Wireless pairing enables users to set up WSNs without pre-installing keys, but current pairing techniques introduce numerous concerns regarding security, hardware expense, and usability. This thesis introduces dynamic Near Field Communication (NFC) pairing, a new pairing technique designed for WSNs. This pairing overcomes the limitations of both key pre-installation and current pairing techniques. Dynamic NFC pairing is as secure as using pre-installed keys, requires only inexpensive …

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Analyses Of Nonlinearity Measures In High-Amplitude Sound Propagation, Michael B. Muhlestein Jul 2013

Analyses Of Nonlinearity Measures In High-Amplitude Sound Propagation, Michael B. Muhlestein

Theses and Dissertations

Military aircraft generate high-amplitude noise which can cause injury to attending personnel. Efforts to mitigate the effects of this noise require a detailed understanding of the propagation of the noise, which was shown previously to be nonlinear. This thesis presents an analysis of high-amplitude noise propagation, emphasizing measures used to quantify the importance of considering nonlinearity. Two measures of the importance of nonlinearity are compared. These measures are the wave steepening factor and a skewness estimate. The wave steepening factor is a measure of how much nonlinear waveform steepening has occurred in a waveform. The skewness estimate is the skewness …

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Bounding The Norm Of Matrix Powers, Daniel Ammon Dowler Jul 2013

Bounding The Norm Of Matrix Powers, Daniel Ammon Dowler

Theses and Dissertations

In this paper I investigate properties of square complex matrices of the form Ak, where A is also a complex matrix, and k is a nonnegative integer. I look at several ways of representing Ak. In particular, I present an identity expressing the kth power of the Schur form T of A in terms of the elements of T, which can be used together with the Schur decomposition to provide an expression of Ak. I also explain bounds on the norm of Ak, including some based on the element-based expression of …

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The Minimum Rank Problem For Outerplanar Graphs, John Henry Sinkovic Jul 2013

The Minimum Rank Problem For Outerplanar Graphs, John Henry Sinkovic

Theses and Dissertations

Given a simple graph G with vertex set V(G)={1,2,...,n} define S(G) to be the set of all real symmetric matrices A such that for all i not equal to j, the ijth entry of A is nonzero if and only if ij is in E(G). The range of the ranks of matrices in S(G) is of interest and can be determined by finding the minimum rank. The minimum rank of a graph, denoted mr(G), is the minimum rank achieved by a matrix in S(G). The maximum nullity of a graph, denoted M(G), is the maximum nullity achieved by a matrix …

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Developmental Signaling Requires Inwardly Rectifying K+ Channels In Drosophila Melanogaster, Giri Raj Dahal Jul 2013

Developmental Signaling Requires Inwardly Rectifying K+ Channels In Drosophila Melanogaster, Giri Raj Dahal

Theses and Dissertations

Inwardly rectifying potassium (IRK/Kir) channels regulate intracellular K+ concentrations and membrane potential. Disruption of Kir2.1 causes dominantly inherited Andersen Tawil Syndrome (ATS). ATS patients suffer from cardiac arrhythmias, periodic paralysis, and cognitive impairment. These symptoms are consistent with current understanding of the role of ion channels in muscle cells and neurons. However, ATS symptoms also include craniofacial and digital deformities such as cleft palate, dental defects, wide set eyes, low set ears, and crooked or fused digits. These developmental defects were not consistent with current understanding of developmental signaling or previously described roles for ion channels. We found that phenotypes …

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A Class Of Univalent Convolutions Of Harmonic Mappings, Matthew Daniel Romney Jul 2013

A Class Of Univalent Convolutions Of Harmonic Mappings, Matthew Daniel Romney

Theses and Dissertations

A planar harmonic mapping is a complex-valued function ƒ : D → C of the form ƒ(x+iy) = u(x,y) + iv(x,y), where u and v are both real harmonic. Such a function can be written as ƒ = h+g where h and g are both analytic; the function w = g'/h' is called the dilatation of ƒ. This thesis considers the convolution or Hadamard product of planar harmonic mappings that are the vertical shears of the canonical half-plane mapping p;(z) = z/(1-z) with respective dilatations e^iθz and e^ipz, θ, p ∈ R. We prove that any such convolution is univalent. …

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Characterization Of Ingaas Quantum Dot Chains, Tyler Drue Park Jul 2013

Characterization Of Ingaas Quantum Dot Chains, Tyler Drue Park

Theses and Dissertations

InGaAs quantum dot chains were grown with a low-temperature variation of the Stranski-Krastanov method, the conventional epitaxial method. This new method seeks to reduce indium segregation and intermixing in addition to giving greater control in the growth process. We used photoluminescence spectroscopy techniques to characterize the quality and electronic structure of these samples. We have recently used a transmission electron microscope to show how the quantum dots vary with annealing temperature. Some questions relating to the morphology of the samples cannot be answered by photoluminescence spectroscopy alone. Using transmission electron microscopy, we verified flattening of the quantum dots with annealing …

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The Role Of Smpb In Licensing Tmrna Entry Into Stalled Ribosomes, Mickey R. Miller Jul 2013

The Role Of Smpb In Licensing Tmrna Entry Into Stalled Ribosomes, Mickey R. Miller

Theses and Dissertations

Ribosomes translate the genetic information contained in mRNAs into protein by linking together amino acids with the help of aminoacyl-tRNAs. In bacteria, protein synthesis stalls when the ribosome reaches the 3'-end of truncated mRNA transcripts lacking a stop codon. Trans-translation is a conserved bacterial quality control process that rescues stalled ribosomes. Transfer-messenger RNA (tmRNA) and its protein partner SmpB mimic a tRNA by entering the A site of the ribosome and accepting the growing peptide chain. The ribosome releases the truncated mRNA and resumes translation on the tmRNA template. The open reading frame found on tmRNA encodes a peptide tag …

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