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Articles 31 - 60 of 101
Full-Text Articles in Physical Sciences and Mathematics
Ontology Aware Software Service Agents: Meeting Ordinary User Needs On The Semantic Web, Muhammed Jassem Al Muhammed
Ontology Aware Software Service Agents: Meeting Ordinary User Needs On The Semantic Web, Muhammed Jassem Al Muhammed
Theses and Dissertations
To achieve the dream of the semantic web, it must be possible for ordinary users to invoke services. It is clear that users need simple-to-invoke-and-use services. This dissertation offers an ontological approach to declaratively create services that users can invoke using free-form, natural-language-like specifications. Our approach uses task ontologies as foundational knowledge. A task ontology consists of a domain ontology and a process ontology. The domain ontology encodes domain information such as possible constraints and instances in terms of object sets, relationship sets among these object sets, and operations over values in object sets and relationship sets. The process ontology …
The Effect Of Nonlinear Propagation On Near-Field Acoustical Holography, Micah Raymond Shepherd
The Effect Of Nonlinear Propagation On Near-Field Acoustical Holography, Micah Raymond Shepherd
Theses and Dissertations
Near-field acoustical holography (NAH) has been used extensively for acoustical imaging of infinitesimal-amplitude (or small-amplitude) sources. However, recent interests are in the application of NAH to image finite-amplitude (or high-amplitude) sources such as jets and rockets. Since NAH is based on linear equations and finite-amplitude sources imply nonlinear effects, which cause shock formation and consequently an altered spectral shape, a feasibility study is carried out to determine the effect of nonlinear propagation on NAH. Jet and rocket sources typically have a distinct spectral shape resembling a ‘haystack’ and center frequencies varying from 30 to 300 Hz. To test the effect …
The Spillable Environment: Expanding A Handheld Device's Screen Real Estate And Interactive Capabilities, Jeffrey S. Clement
The Spillable Environment: Expanding A Handheld Device's Screen Real Estate And Interactive Capabilities, Jeffrey S. Clement
Theses and Dissertations
Handheld devices have a limited amount of screen real estate. If a handheld device could take advantage of larger screens, it would create a more powerful user interface and environment. As time progresses, Moore's law predicts that the computational power of handheld devices will increase dramatically in the future, promoting the interaction with a larger screen. Users can then use their peripheral vision to recognize spatial relationships between objects and solve problems more easily with this integrated system. In the spillable environment, the handheld device uses a DiamondTouch Table, a large, touch-sensitive horizontal table, to enhance the viewing environment. When …
An Adaptive Bayesian Approach To Bernoulli-Response Clinical Trials, Andrew W. Stacey
An Adaptive Bayesian Approach To Bernoulli-Response Clinical Trials, Andrew W. Stacey
Theses and Dissertations
Traditional clinical trials have been inefficient in their methods of dose finding and dose allocation. In this paper a four-parameter logistic equation is used to model the outcome of Bernoulli-response clinical trials. A Bayesian adaptive design is used to fit the logistic equation to the dose-response curve of Phase II and Phase III clinical trials. Because of inherent restrictions in the logistic model, symmetric candidate densities cannot be used, thereby creating asymmetric jumping rules inside the Markov chain Monte Carlo algorithm. An order restricted Metropolis-Hastings algorithm is implemented to account for these limitations. Modeling clinical trials in a Bayesian framework …
Compartmentalization Of Hiv-1 In The Secondary Lymphoid Tissues, James Peter Gregson
Compartmentalization Of Hiv-1 In The Secondary Lymphoid Tissues, James Peter Gregson
Theses and Dissertations
Follicular dendritic cells (FDCs) reside in the lymphoid follicles of the secondary lymphoid tissues (sLTs). Following the infection of an individual with human immunodeficiency virus type 1 (HIV-1), viral particles are trapped in massive quantities on the surfaces of FDCs. HIV-1 viral compartments are cell types or tissues between which there is a restriction of virus flow. Compartmentalization of HIV-1 creates numerous sites within the body in which the virus can undergo independent evolution, giving rise to a more diverse total viral population. Given the sessile nature of the FDC, I hypothesized that contrary to common assumptions, FDC-trapped HIV-1 is …
Text Identification By Example, Daniel Joseph Preece
Text Identification By Example, Daniel Joseph Preece
Theses and Dissertations
The World-Wide Web contains a lot of information and reading through the web pages to collect this information is tedious, time consuming and error prone. Users need an automated solution for extracting or highlighting the data that they are interested in. Building a regular expression to match the text they are interested in will automate the process, but regular expressions are hard to create and certainly are not feasible for non-programmers to construct. Text Identification by Example (TIBE) makes it easier for end-users to harvest information from the web and other text documents. With TIBE, training text classifiers from user-selected …
Sampling Methods In Ray-Based Global Illumination, David Cline
Sampling Methods In Ray-Based Global Illumination, David Cline
Theses and Dissertations
In computer graphics, algorithms that attempt to create photographic images by simulating light transport are collectively known as Global Illumination methods. The most versatile of these are based on ray tracing (following ray paths through a scene), and numerical integration using random or quasi-random sampling. While ray tracing and sampling methods in global illumination have progressed much in the last two decades, the goal of fast and accurate simulation of light transport remains elusive. This dissertation presents a number of new sampling methods that attempt to address some of the shortcomings of existing global illumination algorithms. The first part of …
On Stability And Evolution Of Solutions In General Relativity, Stephen M. Taylor
On Stability And Evolution Of Solutions In General Relativity, Stephen M. Taylor
Theses and Dissertations
This thesis is concerned with several problems in general relativity and low energy string theory that are pertinent to the time evolution of the gravitational field. We present a formulation of the Einstein field equations in terms of variational techniques borrowed from geometric analysis. These equations yield the evolution equations for the Cauchy problems of both general relativity and low energy string theory. We then proceed to investigate the evolutionary linear stability of Schwarzschild-like solutions in higher dimensional relativity called black strings. These objects are determined to be linearly unstable. This motivates a further stability analysis of the charged p-brane …
Development Of Informative Priors In Microarray Studies, Kassandra M. Fronczyk
Development Of Informative Priors In Microarray Studies, Kassandra M. Fronczyk
Theses and Dissertations
Microarrays measure the abundance of DNA transcripts for thousands of gene sequences, simultaneously facilitating genomic comparisons across tissue types or disease status. These experiments are used to understand fundamental aspects of growth and development and to explore the underlying genetic causes of many diseases. The data from most microarray studies are found in open-access online databases. Bayesian models are ideal for the analysis of microarray data because of their ability to integrate prior information; however, most current Bayesian analyses use empirical or flat priors. We present a Perl script to build an informative prior by mining online databases for similar …
Seismic And Well Log Attribute Analysis Of The Jurassic Entrada/Curtis Interval Within The North Hill Creek 3d Seismic Survey, Uinta Basin, Utah, A Case History, Ryan J. Oneal
Theses and Dissertations
3D seismic attribute analysis of the Jurassic Entrada/Curtis interval within the North Hill Creek (NHC) survey has been useful in delineating reservoir quality eolian-influenced dune complexes. Amplitude, average reflection strength and spectral decomposition appear to be most useful in locating reservoir quality dune complexes, outlining their geometry and possibly displaying lateral changes in thickness. Cross sectional views displaying toplap features likely indicate an unconformity between Entrada clinoforms below and Curtis planar beds above. This relationship may aid the explorationist in discovering this important seismic interval. Seismic and well log attribute values were cross plotted and have revealed associations between these …
Development Of Chemomechanical Functionalization And Nanografting On Silicon Surfaces, Michael Vernon Lee
Development Of Chemomechanical Functionalization And Nanografting On Silicon Surfaces, Michael Vernon Lee
Theses and Dissertations
Progress in chemomechanical functionalization was made by investigating the binding of molecules and surface coverage on the silicon surface, demonstrating functionalization of silicon with gases by chemomechanical means, analyzing atomic force microscopy probe tip wear in atomic force microscopy (AFM) chemomechanical nanografting, combining chemomechanical functionalization and nanografting to pattern silicon with an atomic force microscope, and extending chemomechanical nanografting to silicon dioxide. Molecular mechanics of alkenes and alkynes bound to Si(001)-2x1 as a model of chemomechanically functionalized surfaces indicated that complete coverage is energetically favorable and becomes more favorable for longer chain species. Scribing a silicon surface in the presence …
Synthesis Of Resveratrol And Its Analogs, Phase-Transfer Catalyzed Asymmetric Glycolate Aldol Reaction, And Total Synthesis Of 8,9-Methylamido-Geldanamycin, Jing Liu
Theses and Dissertations
The phytoalexin resveratrol and its acetyl analogs have been made using a decarbonylative Heck reaction. The acid chloride derived from 3,5-dihydroxybenzoic acid was coupled with suitable protected 4-hydroxystyrene in the presence of palladium acetate and N,N-bis-(2,6-diisopropylphenyl)-4,5-dihydro imidazolium chloride to give the substituted stilbene in good yield as the key step. Human HL-60 cell assays showed the 4'-acetyl resveratrol variant improved activity (ED50 17 μM) relative to resveratrol (24 μM). Cinchona phase-transfer catalysts (PTC) were developed for glycolate aldol reactions to give differentially protected 1,2-diol products. Silyl enol ether of diphenylmethoxy-2,5-dimethoxyacetophenone reacted to generate benzhydryl-protected products. O-Allyl trifluorobenzyl cinchonium hydrodifluoride (20 …
Microfacies Analysis, Sedimentary Petrology, And Reservoir Characterization Of The Sinbad Limestone Based Upon Surface Exposures In The San Rafael Swell, Utah, Caleb R. Osborn
Theses and Dissertations
The Lower Triassic Sinbad Limestone Member of the Moenkopi Formation has produced minor amounts of oil in the Grassy Trail Creek field near Green River, Utah and is present below much of central Utah including the recently discovered Covenant field. Superb outcrops of this thin (15 m), mixed carbonate-silicilastic unit in the San Rafael Swell permit detailed analysis of its vertical and lateral reservoir heterogeneity. Vertically, the Sinbad Limestone comprises three facies associations: (A) a basal storm-dominated, well-circulated skeletal-oolitic-peloidal limestone association, (B) a storm-dominated, poorly-circulated hummocky cross-stratified siliciclastic/peloidal association, and (C) a capping peritidal cross-bedded oolitic dolograinstone association. Eleven microfacies …
The Minimum Rank Problem Over Finite Fields, Jason Nicholas Grout
The Minimum Rank Problem Over Finite Fields, Jason Nicholas Grout
Theses and Dissertations
We have two main results. Our first main result is a sharp bound for the number of vertices in a minimal forbidden subgraph for the graphs having minimum rank at most 3 over the finite field of order 2. We also list all 62 such minimal forbidden subgraphs and show that many of these are minimal forbidden subgraphs for any field. Our second main result is a structural characterization of all graphs having minimum rank at most k for any k over any finite field. This characterization leads to a very strong connection to projective geometry and we apply projective …
Statistical Considerations In Designing For Biomarker Detection, Trenton C. Pulsipher
Statistical Considerations In Designing For Biomarker Detection, Trenton C. Pulsipher
Theses and Dissertations
The purpose of this project is to develop a statistical method for use in rapid detection of biological agents using portable gas chromatography mass spectrometry (GC/MS) devices. Of particular interest is 2,6-pyridinedicarboxylic acid (dipicolinic acid, or DPA), a molecule that is present at high concentrations in spores of Clostridium and Bacillus, the latter of which includes the threat organism Bacillus anthracis, or anthrax. Dipicolinic acid may be useful as a first-step discriminator of the biological warfare agent B. anthracis. The results of experiments with B. anthracis Sterne strain and Bacillus thuringiensis spores lead to a conceptual model for the chemical …
Infinite Product Group, Keith G. Penrod
Infinite Product Group, Keith G. Penrod
Theses and Dissertations
The theory of infinite multiplication has been studied in the case of the Hawaiian earring group, and has been seen to simplify the description of that group. In this paper we try to extend the theory of infinite multiplication to other groups and give a few examples of how this can be done. In particular, we discuss the theory as applied to symmetric groups and braid groups. We also give an equivalent definition to K. Eda's infinitary product as the fundamental group of a modified wedge product.
Pipe Diagrams For Thompson's Group F, Aaron L. Peterson
Pipe Diagrams For Thompson's Group F, Aaron L. Peterson
Theses and Dissertations
We review the definition and standard description of Thompson's Group F. We define the set of pipe diagrams and show that this set forms a group isomorphic to F. We use pipe diagrams to prove two theorems about giving a minimal representation for an arbitrary element of F.
Development Of A Mevva Based Beryllium-7 Plasma Source, David K. Olson
Development Of A Mevva Based Beryllium-7 Plasma Source, David K. Olson
Theses and Dissertations
We have designed a new type of plasma gun ion source for a Malmberg-Penning trap based on Metal Vapor Vacuum Arc (MeVVA) ion source designs. Our primary intent with this MeVVA-type source is to create a confinable beryllium-7 (7-Be) plasma. 7-Be is a peculiar isotope due to its varying radioactive decay half-life in different electro-chemical configurations. It is also found in an unexpected abundance at high altitudes of the Earth's atmosphere. It is possible ioniziation affects the radioactivity of the isotope, partly explaining this discrepancy with atmospheric models. The short half-life of 7-Be requires us to replace the sample inside …
Or Best Offer: A Privacy Policy Negotiation Protocol, Daniel David Walker
Or Best Offer: A Privacy Policy Negotiation Protocol, Daniel David Walker
Theses and Dissertations
Users today are concerned about how their information is collected, stored and used by Internet sites. Privacy policy languages, such as the Platform for Privacy Preferences (P3P), allow websites to publish their privacy practices and policies in machine readable form. Currently, software agents designed to protect users' privacy follow a "take it or leave it" approach when evaluating these privacy policies. This approach is inflexible and gives the server ultimate control over the privacy of web transactions. Privacy policy negotiation is one approach to leveling the playing field by allowing a client to negotiate with a server to determine how …
A Modified Cluster-Weighted Approach To Nonlinear Time Series, Mark Ballatore Lyman
A Modified Cluster-Weighted Approach To Nonlinear Time Series, Mark Ballatore Lyman
Theses and Dissertations
In many applications involving data collected over time, it is important to get timely estimates and adjustments of the parameters associated with a dynamic model. When the dynamics of the model must be updated, time and computational simplicity are important issues. When the dynamic system is not linear the problem of adaptation and response to feedback are exacerbated. A linear approximation of the process at various levels or “states” may approximate the non-linear system. In this case the approximation is linear within a state and transitions from state to state over time. The transition probabilities are parametrized as a Markov …
Synthesis And Antiviral Evaluation Of Some 3'-Carboxymethyl-3'-Deoxyadenosine Derivatives, Houguang Shi
Synthesis And Antiviral Evaluation Of Some 3'-Carboxymethyl-3'-Deoxyadenosine Derivatives, Houguang Shi
Theses and Dissertations
3'-Carboxymethyl-3'-deoxyadenosine derivatives were prepared from 2'-O-TBDMS-3'-deoxy-3'-[(ethoxycarbonyl)methyl]adenosine (1) via simple and efficient procedures. Conversion of 1 to 5'-azido-2'-O-TBDMS-3', 5'-dideoxy -3'-[(ethoxycarbonyl) methyl] adenosine (4) was accomplished via a novel one-pot method employing 5'-activation (TosCl) followed by efficient nucleophilic displacement with tetramethylguanidinium azide. Compound 4 was converted to a 5'-[(N-methylcarbamoyl)amino] derivative (5) via one-pot reduction/acylation employing H2/Pd-C followed by treatment with p-nitrophenyl N-methylcarbamate. The latter step of this two-step process required an efficient source of p-nitrophenyl N-methylcarbamate, thus a highly efficient new method for preparing p-nitrophenyl N-alkylcarbamate was developed. N6-phenylcarbamoyl groups were introduced by treatment with phenylisocyanate, and an efficient new method for …
The Smallest Base And Precious Metal Deposits In The World: Vapor Transport And Deposition Of Co-Cu-Sn-Ag Alloys In Vesicles, Elizabeth Adele Outdoor Hunter
The Smallest Base And Precious Metal Deposits In The World: Vapor Transport And Deposition Of Co-Cu-Sn-Ag Alloys In Vesicles, Elizabeth Adele Outdoor Hunter
Theses and Dissertations
Metallic bronze-Co-Ag alloys ranging from1-90 µm have been discovered in bomb and lava vesicles from the mafic volcanoes of Kilauea in Hawaii and Vesuvius, Stromboli and Etna in Italy. It is inferred that the metals for these alloys were transported (in part) as chloride complexes, and that the metal ratios in the alloys may be a function of S/Cl. Alloy compositions in each system are extremely heterogeneous with Co concentrations from 1% to 94%, Cu from 2% to 89%, Sn from 1% to 22% and Ag from 0.5% to 42%. Maximum abundances (in wt%) of other trace or minor elements …
A Comparative Simulation Study Of Robust Estimators Of Standard Errors, Natalie Johnson
A Comparative Simulation Study Of Robust Estimators Of Standard Errors, Natalie Johnson
Theses and Dissertations
The estimation of standard errors is essential to statistical inference. Statistical variability is inherent within data, but is usually of secondary interest; still, some options exist to deal with this variability. One approach is to carefully model the covariance structure. Another approach is robust estimation. In this approach, the covariance structure is estimated from the data. White (1980) introduced a biased, but consistent, robust estimator. Long et al. (2000) added an adjustment factor to White's estimator to remove the bias of the original estimator. Through the use of simulations, this project compares restricted maximum likelihood (REML) with four robust estimation …
Extreme Ultraviolet Polarimetry With Laser-Generated High-Order Harmonics, Nicole Brimhall
Extreme Ultraviolet Polarimetry With Laser-Generated High-Order Harmonics, Nicole Brimhall
Theses and Dissertations
We developed an extreme ultraviolet (EUV) polarimeter, which employs laser-generated high-order harmonics as the light source. This relatively high-flux directional EUV source has available wavelengths between 8 nm and 62 nm and easily rotatable linear polarization. The polarimeter will aid researchers at BYU in characterizing EUV thin films and improving their understanding of materials for use in EUV optics. This first-time workhorse application of laser high harmonics enables polarization-sensitive reflection measurements not previously available in the EUV. We have constructed a versatile positioning system that places harmonics on the microchannel plate detector with an accuracy of 0.3 mm, which allows …
Reservoir Characterization And Outcrop Analogs To The Navajo Sandstone In The Central Utah Thrust Belt Exploration Play, Ashley Dalrymple
Reservoir Characterization And Outcrop Analogs To The Navajo Sandstone In The Central Utah Thrust Belt Exploration Play, Ashley Dalrymple
Theses and Dissertations
Reservoir heterogeneity plays an important role in oil field economics and completion strategies. We herein characterize the reservoir heterogeneity of the Early Jurassic Navajo Sandstone in the Justensen Flat/Devils Canyon area of the San Rafael Swell, Utah. These outcrops are located approximately 60 kilometers (45 mi) east of the recently discovered Covenant oil field which is located in the central Utah thrust belt exploration play. The reservoir for the Covenant field is the Navajo Sandstone. This study can serve as an outcrop analogue for this developing play and other eolian reservoirs worldwide. There are eight facies within the Navajo Sandstone …
Sensitivity To Distributional Assumptions In Estimation Of The Odp Thresholding Function, Wendy Jill Bunn
Sensitivity To Distributional Assumptions In Estimation Of The Odp Thresholding Function, Wendy Jill Bunn
Theses and Dissertations
Recent technological advances in fields like medicine and genomics have produced high-dimensional data sets and a challenge to correctly interpret experimental results. The Optimal Discovery Procedure (ODP) (Storey 2005) builds on the framework of Neyman-Pearson hypothesis testing to optimally test thousands of hypotheses simultaneously. The method relies on the assumption of normally distributed data; however, many applications of this method will violate this assumption. This thesis investigates the sensitivity of this method to detection of significant but nonnormal data. Overall, estimation of the ODP with the method described in this thesis is satisfactory, except when the nonnormal alternative distribution has …
Extensible Pre-Authentication In Kerberos, Phillip L. Hellewell
Extensible Pre-Authentication In Kerberos, Phillip L. Hellewell
Theses and Dissertations
Organizations need to provide services to a wide range of people, including strangers outside their local security domain. As the number of users grows larger, it becomes increasingly tedious to maintain and provision user accounts. It remains an open problem to create a system for provisioning outsiders that is secure, flexible, efficient, scalable, and easy to manage. Kerberos is a secure, industry-standard protocol. Currently, Kerberos operates as a closed system; all users must be specified upfront and managed on an individual basis. This paper presents EPAK (Extensible Pre-Authentication in Kerberos), a framework that enables Kerberos to operate as an open …
Obstacle Avoidance And Path Traversal Using Interactive Machine Learning, Jonathan M. Turner
Obstacle Avoidance And Path Traversal Using Interactive Machine Learning, Jonathan M. Turner
Theses and Dissertations
Recently there has been a growing interest in using robots in activities that are dangerous or cost prohibitive for humans to do. Such activities include military uses and space exploration. While robotic hardware is often capable of being used in these types of situations, the ability of human operators to control robots in an effective manner is often limited. This deficiency is often related to the control interface of the robot and the level of autonomy that control system affords the human operator. This thesis describes a robot control system, called the safe/unsafe system, which gives a human operator the …
Conceptual Xml For Systems Analysis, Reema Al-Kamha
Conceptual Xml For Systems Analysis, Reema Al-Kamha
Theses and Dissertations
Because XML has become a new standard for data representation, there is a need for a simple conceptual model that works well with XML-based development. In this research we present a conceptual model for XML, called C-XML, which meets this new need of systems analysts who store their data using XML. We describe our implementation of an automatic conversion from XML Schema to C-XML that preserves information and constraints. With this conversion, we can view an XML Schema instance graphically at a higher level of abstraction. We also describe our implementation of an automatic conversion from C-XML to XML Schema. …
Intelligent Rotoscoping: A Semi-Automated Interactive Boundary Tracking Approach To Video Segmentation, Seth R. Holladay
Intelligent Rotoscoping: A Semi-Automated Interactive Boundary Tracking Approach To Video Segmentation, Seth R. Holladay
Theses and Dissertations
Video segmentation is an application of computer vision aimed at automating the extraction of an object from a series of video frames. However, it is a difficult problem, especially to compute at real-time, interactive rates. Although general application to video is difficult because of the wide range of image scenarios, user interaction can help to reduce the problem space and speed up the computation. This thesis presents a fast object-tracking tool that selects an object from a series of frames based on minimal user input. Our Intelligent Rotoscoping tool aims for increased speed and accuracy over other video segmentation tools, …