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Articles 2041 - 2070 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Live Surface, Christopher J. Armstrong Feb 2007

Live Surface, Christopher J. Armstrong

Theses and Dissertations

Live Surface allows users to segment and render complex surfaces from 3D image volumes at interactive (sub-second) rates using a novel, Cascading Graph Cut (CGC). Live Surface consists of two phases. (1) Preprocessing for generation of a complete 3D watershed hierarchy followed by tracking of all catchment basin surfaces. (2) User interaction in which, with each mouse movement, the 3D object is selected and rendered in real time. Real-time segmentation is ccomplished by cascading through the 3D watershed hierarchy from the top, applying graph cut successively at each level only to catchment basins bordering the segmented surface from the previous …

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Analysis Using Smoothing Via Penalized Splines As Implemented In Lme() In R, John R. Howell Feb 2007

Analysis Using Smoothing Via Penalized Splines As Implemented In Lme() In R, John R. Howell

Theses and Dissertations

Spline smoothers as implemented in common mixed model software provide a familiar framework for estimating semi-parametric and non-parametric models. Following a review of literature on splines and mixed models, details for implementing mixed model splines are presented. The examples use an experiment in the health sciences to demonstrate how to use mixed models to generate the smoothers. The first example takes a simple one-group case, while the second example fits an expanded model using three groups simultaneously. The second example also demonstrates how to fit confidence bands to the three-group model. The examples use mixed model software as implemented in …

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Performance Evaluation Of Vision-Based Navigation And Landing On A Rotorcraft Unmanned Aerial Vehicle, David Hubbard, Timothy W. Mclain, Bryan S. Morse, Colin Theodore, Mark Tischler Feb 2007

Performance Evaluation Of Vision-Based Navigation And Landing On A Rotorcraft Unmanned Aerial Vehicle, David Hubbard, Timothy W. Mclain, Bryan S. Morse, Colin Theodore, Mark Tischler

Faculty Publications

A Rotorcraft UAV provides an ideal experimental platform for vision-based navigation. This paper describes the flight tests of the US Army PALACE project, which implements Moravec’s pseudo-normalized correlation tracking algorithm. The tracker uses the movement of the landing site in the camera, a laser range, and the aircraft attitude from an IMU to estimate the relative motion of the UAV. The position estimate functions as a GPS equivalent to enable the rotorcraft to maneuver without the aid of GPS. With GPS data as a baseline, tests were performed in simulation and in flight that measure the accuracy of the position …

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Human–Robot Interaction: A Survey, Michael A. Goodrich, Alan C. Schultz Feb 2007

Human–Robot Interaction: A Survey, Michael A. Goodrich, Alan C. Schultz

Faculty Publications

Human–Robot Interaction (HRI) has recently received considerable attention in the academic community, in labs, in technology companies, and through the media. Because of this attention, it is desirable to present a survey of HRI to serve as a tutorial to people outside the field and to promote discussion of a unified vision of HRI within the field. The goal of this review is to present a unified treatment of HRI-related problems, to identify key themes, and discuss challenge problems that are likely to shape the field in the near future. Although the review follows a survey structure, the goal of …

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Interactive Image Repair With Assisted Structure And Texture Completion, Teryl Arnold, Bryan S. Morse Feb 2007

Interactive Image Repair With Assisted Structure And Texture Completion, Teryl Arnold, Bryan S. Morse

Faculty Publications

Removing image defects in an undetectable manner has been studied for its many useful and varied applications. In many cases the desired result may be ambiguous from the image data alone and needs to be guided by a user’s knowledge of the intended result. This paper presents a framework for interactively incorporating user guidance into the filling-in process, more effectively using user input to fill in damaged regions in an image. This framework contains five main steps: first, the scratch or defect is detected; second, the edges outside the defect are detected; third, curves are fit to the detected edges; …

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Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt Feb 2007

Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt

Theses and Dissertations

Video acquired using a camera mounted on a mini Unmanned Air Vehicle (mUAV) may be very helpful in Wilderness Search and Rescue and many other applications but is commonly plagued with limited spatial and temporal field of views, distractive jittery motions, disorienting rotations, and noisy and distorted images. These problems collectively make it very difficult for human viewers to identify objects of interest as well as infer correct orientations throughout the video. In order to expand the temporal and spatial field of view, stabilize, and better orient users of noisy and distorted mUAV video, a method is proposed of estimating …

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Selecting The Best Linear Mixed Model Using Predictive Approaches, Jun Wang Jan 2007

Selecting The Best Linear Mixed Model Using Predictive Approaches, Jun Wang

Theses and Dissertations

The linear mixed model is widely implemented in the analysis of longitudinal data. Inference techniques and information criteria are available and well-studied for goodness-of-fit within the linear mixed model setting. Predictive approaches such as R-squared, PRESS, and CCC are available for the linear mixed model but require more research (Edward, 2005). This project used simulation to investigate the performance of R-squared, PRESS, CCC, Pseudo F-test and information criterion for goodness-of-fit within the linear mixed model framework. Marginal and conditional approaches for these predictive statistics were studied under different variance-covariance structures. For compound symmetry structure, the success rates for all 17 …

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Banda Forearc Metamorphic Rocks Accreted To The Australian Continental Margin: Detailed Analysis Of The Lolotoi Complex Of East Timor, Carl Eldon Standley Jan 2007

Banda Forearc Metamorphic Rocks Accreted To The Australian Continental Margin: Detailed Analysis Of The Lolotoi Complex Of East Timor, Carl Eldon Standley

Theses and Dissertations

Petrologic, structural and age investigations of the Lolotoi Complex of East Timor indicate that it is part of a group of thin metamorphic klippen found throughout the region that were detached from the Banda forearc and accreted to the NW Australian continental margin during Late Miocene to Present arc-continent collision. Metamorphic rock types are dominated by (in order of greatest to least abundance), greenschist, graphitic phyllite, quartz-mica schist, amphibolite and pelitic schist. Mineral, whole rock, and trace element geochemical analyses of metabasites indicate that protolith compositions are consistent with tholeiitic basalt and basaltic andesite with mixed MORB and oceanic arc …

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System For Collision Detection Between Deformable Models Built On Axis Aligned Bounding Boxes And Gpu Based Culling, David Owen Tuft Jan 2007

System For Collision Detection Between Deformable Models Built On Axis Aligned Bounding Boxes And Gpu Based Culling, David Owen Tuft

Theses and Dissertations

Collision detection between deforming models is a difficult problem for collision detection systems to handle. This problem is even more difficult when deformations are unconstrained, objects are in close proximity to one another, and when the entity count is high. We propose a method to perform collision detection between multiple deforming objects with unconstrained deformations that will give good results in close proximities. Currently no systems exist that achieve good performance on both unconstrained triangle level deformations and deformations that preserve edge connectivity. We propose a new system built as a combination of Graphics Processing Unit (GPU) based culling and …

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Eliminating Redundant And Less-Informative Rss News Articles Based On Word Similarity And A Fuzzy Equivalence Relation, Ian Garcia Jan 2007

Eliminating Redundant And Less-Informative Rss News Articles Based On Word Similarity And A Fuzzy Equivalence Relation, Ian Garcia

Theses and Dissertations

The Internet has marked this era as the information age. There is no precedent in the amazing amount of information, especially network news, that can be accessed by Internet users these days. As a result, the problem of seeking information in online news articles is not the lack of them but being overwhelmed by them. This brings huge challenges regarding processing of online news feeds, i.e., how to determine which news article is important, how to determine the quality of each news article, and how to filter irrelevant and redundant information. In this thesis, we propose a method for filtering …

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Strain-Based Electrical Properties Of Systems Of Carbon Nanotubes Embedded In Parylene, David D. Allred, Jon Brame, Johnathan Goodsell, Stephanie Getty Jan 2007

Strain-Based Electrical Properties Of Systems Of Carbon Nanotubes Embedded In Parylene, David D. Allred, Jon Brame, Johnathan Goodsell, Stephanie Getty

Faculty Publications

We have fabricated flexible electronic devices to test the strain-based change in resistance of a network of single-walled carbon nanotubes (SWCNTs) for use in microscale, high resolution magnetometry. To do this, we first develop a simple, reliable method to obtain catalyst nanoparticles for carbon nanotube growth through indirect, thin-film evaporation. Next we fabricate a two-terminal SWCNT device on a rigid substrate. We then transfer the device, intact, to a flexible substrate for strain testing. Herein, we report progress in growth and measurement techniques.

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Implicit Affinity Networks, Matthew Scott Smith Jan 2007

Implicit Affinity Networks, Matthew Scott Smith

Theses and Dissertations

Although they clearly exist, affinities among individuals are not all easily identified. Yet, they offer unique opportunities to discover new social networks, strengthen ties among individuals, and provide recommendations. We propose the idea of Implicit Affinity Networks (IANs) to build, visualize, and track affinities among groups of individuals. IANs are simple, interactive graphical representations that users may navigate to uncover interesting patterns. This thesis describes a system supporting the construction of IANs and evaluates it in the context of family history and online communities.

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Skuery: Manipulation Of S-Expressions Using Xquery Techniques, Kevin Burke Tew Jan 2007

Skuery: Manipulation Of S-Expressions Using Xquery Techniques, Kevin Burke Tew

Theses and Dissertations

Data query operations inside programming languages presently perform their functions through the use of domain-specific, declarative expressions and by way of course-grain, API library calls. These methods of operation are practiced by relational databases as well as semistructured XML data stores. Layers of translation, which are necessary to transform data and instructions from the domain of programming languages to data query systems, negtatively effect the performance of data query operations. Skuery resolves this impedance by adopting XML as a native data type with a native representation (SXML). Likewise, query operations are defined in a general purpose programming language (Scheme in …

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Clustering Streaming Music Via The Temporal Similarity Of Timbre, Jacob Merrell, Bryan S. Morse, Dan A. Ventura Jan 2007

Clustering Streaming Music Via The Temporal Similarity Of Timbre, Jacob Merrell, Bryan S. Morse, Dan A. Ventura

Faculty Publications

We consider the problem of measuring the similarity of streaming music content and present a method for modeling, on the fly, the temporal progression of a song’s timbre. Using a minimum distance classification scheme, we give an approach to classifying streaming music sources and present performance results for auto-associative song identification and for content-based clustering of streaming music. We discuss possible extensions to the approach and possible uses for such a system.

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A Cognitive Robotics Approach To Comprehending Human Language And Behaviors, Deryle W. Lonsdale, D. Paul Benjamin, Damian Lyons Jan 2007

A Cognitive Robotics Approach To Comprehending Human Language And Behaviors, Deryle W. Lonsdale, D. Paul Benjamin, Damian Lyons

Faculty Publications

The ADAPT project is a collaboration of researchers in linguistics, robotics and artificial intelligence at three universities. We are building a complete robotic cognitive architecture for a mobile robot designed to interact with humans in a range of environments, and which uses natural language and models human behavior. This paper concentrates on the HRI aspects of ADAPT, and especially on how ADAPT models and interacts with humans.

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Analogical Modeling: An Update, Deryle W. Lonsdale, David Eddington Jan 2007

Analogical Modeling: An Update, Deryle W. Lonsdale, David Eddington

Faculty Publications

Analogical modeling is a supervised exemplar-based approach that has been widely applied to predict linguistic behavior. The paradigm has been well documented in the linguistics and cognition literature, but is less well known to the machine learning community. This paper sets out some of the basics of the approach, including a simplified example of the fundamental algorithm’s operation. It then surveys some of the recent analogical modeling language applications, and sketches how the computational system has been enhanced lately to offer users increased flexibility and processing power. Some comparisons and contrasts are drawn between analogical modeling and other language modeling …

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Generating Ontologies Via Language Components And Ontology Reuse, Deryle W. Lonsdale, Yihong Ding, David W. Embley, Martin Hepp, Li Xu Jan 2007

Generating Ontologies Via Language Components And Ontology Reuse, Deryle W. Lonsdale, Yihong Ding, David W. Embley, Martin Hepp, Li Xu

Faculty Publications

Realizing the Semantic Web involves creating ontologies, a tedious and costly challenge. Reuse can reduce the cost of ontology engineering. Semantic Web ontologies can provide useful input for ontology reuse. However, the automated reuse of such ontologies remains underexplored. This paper presents a generic architecture for automated ontology reuse. With our implementation of this architecture, we show the practicality of automating ontology generation through ontology reuse. We experimented with a large generic ontology as a basis for automatically generating domain ontologies that fit the scope of sample natural-language web pages. The results were encouraging, resulting in five lessons pertinent to …

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Screencrayons: Using Screen Captures For Annotation And Research, Trent Alan Taufer Dec 2006

Screencrayons: Using Screen Captures For Annotation And Research, Trent Alan Taufer

Theses and Dissertations

In a world full of digital information we should be able to easily collect, organize, annotate, and leverage information from many different sources. This should be easy to do and not interrupt our normal workflow. A system to support information collection and organization should be user-friendly and as unobtrusive as possible, while still allowing for flexible and intelligent annotation. It should also be able to leverage the inherent information content of a collection of annotated information. We present a system that will demonstrate how these ideas can come together to make information collection easier and more productive. The system facilitates …

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Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson Dec 2006

Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson

Theses and Dissertations

The purpose of this research is to ascertain potential iris scan data variations from near infrared waves derived from fluorescent illumination. Prior studies of iris data variances from infrared wave interference of halogen, incandescent, and sunlight with iris cameras suggest that similar changes may exist under near infrared wavelengths from fluorescent light. The concern is that the fluorescent energy emission may interfere with the near infrared detection of an iris camera. An iris camera is used to measure human eye characteristics known as biometrics. If such infrared emission is statistically significant, then it can alter the validity of the iris …

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Life Data Analysis Of Repairable Systems: A Case Study On Brigham Young University Media Rooms, Stephen Oluaku Manortey Dec 2006

Life Data Analysis Of Repairable Systems: A Case Study On Brigham Young University Media Rooms, Stephen Oluaku Manortey

Theses and Dissertations

It is an undisputable fact that most systems, upon consistence usage are bound to fail in the performance of their intended functions at a point in time. When this occurs, various strategies are set in place to restore them back to a satisfactory performance. This may include replacing the failed component with a new one, swapping parts, resetting adjustable parts to mention but a few. Any such system is referred to as a repairable system. There is the need to study these systems and use statistical models to predict their failing time and be able to set modalities in place …

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Development Of Polymer Monoliths For The Analysis Of Peptides And Proteins, Binghe Gu Dec 2006

Development Of Polymer Monoliths For The Analysis Of Peptides And Proteins, Binghe Gu

Theses and Dissertations

Several novel polymer monoliths for the analysis of peptides and proteins were synthesized using polyethylene glycol diacrylate (PEGDA) as crosslinker. Photo-initiated copolymerization of polyethylene glycol methyl ether acrylate and PEGDA yielded an inert monolith that could be used for size exclusion liquid chromatography of peptides and proteins. This macroscopically uniform monolith did not shrink or swell in either water or tetrahydrofuran. More importantly, it was found to resist adsorption of both acidic and basic proteins in aqueous buffer without any organic solvent additives. A strong cation-exchange polymer monolith was synthesized by copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and PEGDA. A ternary …

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Synthesis And Optical Properties Of Four Oligothiophene-Ruthenium Complexes And Synthesis Of A Bidentate Ligand For C-F Bond Activation, Joseph S. Bair Dec 2006

Synthesis And Optical Properties Of Four Oligothiophene-Ruthenium Complexes And Synthesis Of A Bidentate Ligand For C-F Bond Activation, Joseph S. Bair

Theses and Dissertations

Photovoltaic cells and fluorescence sensing are two important areas of research in chemistry. The combination of photon-activated electron donors with electron acceptors provides a strong platform for the study of optical devices. A series of four oligothiophene-ruthenium complexes has been synthesized. Variation in oligothiophene length and bipyridine substitution allowed comparison of these variables on electronic properties. The longer oligothiophenes display lower energy absorption and emission compared to the shorter ones. Aromatic conjugation appears more complete with para-, rather than meta-, substitution. Oligothiophenes and Ru(bpy)32+ are highly fluorescent individually, but fluorescence is quenched when connected. Bonds of carbon to fluorine are …

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Generating Paraphrases With Greater Variation Using Syntactic Phrases, Rebecca Diane Madsen Dec 2006

Generating Paraphrases With Greater Variation Using Syntactic Phrases, Rebecca Diane Madsen

Theses and Dissertations

Given a sentence, a paraphrase generation system produces a sentence that says the same thing but usually in a different way. The paraphrase generation problem can be formulated in the machine translation paradigm; instead of translation of English to a foreign language, the system translates an English sentence (for example) to another English sentence. Quirk et al. (2004) demonstrated this approach to generate almost 90% acceptable paraphrases. However, most of the sentences had little variation from the original input sentence. Leveraging syntactic information, this thesis project presents an approach that successfully generated more varied paraphrase sentences than the approach of …

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Computationally Modeling The Effects Of Surface Roughness On Soft X-Ray Multilayer Reflectors, Jedediah Edward Jensen Johnson Dec 2006

Computationally Modeling The Effects Of Surface Roughness On Soft X-Ray Multilayer Reflectors, Jedediah Edward Jensen Johnson

Theses and Dissertations

Electromagnetic scattering from a rough two dimensional homogeneous scatterer has been computationally modeled. The scatterer is intended to simulate reflection from a two interface multilayer. The rough scatterer was created from Gaussian random points centered about an ideal interface. The points were connected with a third order spline interpolant which accounts for correlation between neighboring surface atoms. The scalar electric field integral equation (EFIE) and magnetic field integral equation (MFIE) were solved using the Nystrom method to obtain the reflected intensity as a function of observation angle. Verification of the accuracy of the code was obtained by means of comparison …

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The Relationship Between The Minimal Rank Of A Tree And The Rank-Spreads Of The Vertices And Edges, John Henry Sinkovic Dec 2006

The Relationship Between The Minimal Rank Of A Tree And The Rank-Spreads Of The Vertices And Edges, John Henry Sinkovic

Theses and Dissertations

Let F be a field, G = (V,E) be an undirected graph on n vertices, and let S(F,G) be the set of all symmetric n × n matrices whose nonzero off-diagonal entries occur in exactly the positions corresponding to the edges of G. Let mr(F,G)be the minimum rank over all matrices in S(F,G). We give a field independent proof of a well-known result that for a tree the sum of its path cover number and minimal rank is equal to the number of vertices in the tree. The rank-spread of a vertex v of G is the difference between the …

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Development Of Methods For The Study Of Phosphoproteins, Zhaoyuan Chen Dec 2006

Development Of Methods For The Study Of Phosphoproteins, Zhaoyuan Chen

Theses and Dissertations

Characterization of phosphoproteins-including detection, identification of phosphoproteins and identification of phosphorylation sites-is mostly done with radiolabeling and proteomic techniques. Three main topics related to phosphoprotein characterization are included in this dissertation. First, large-scale characterization of the CHO (Chinese hamster ovary) cell phosphoproteome was done using two dimensional gel electrophoresis (2DE) separation, visualization of phosphoproteins by radiolabeling or a phosphoprotein specific dye, followed by MALDI-TOF identification. Because radiolabeling of phosphoproteins is very sensitive and straightforward to quantify, such analysis can give a clear picture of the relative phosphosphorylation of proteins present in a sample. But there are also limitations to this …

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Contour Encoded Compression And Transmission, Christopher B. Nelson Nov 2006

Contour Encoded Compression And Transmission, Christopher B. Nelson

Theses and Dissertations

As the need for digital libraries, especially genealogical libraries, continues to rise, the need for efficient document image compression is becoming more and more apparent. In addition, because many digital library users access them from dial-up Internet connections, efficient strategies for compression and progressive transmission become essential to facilitate browsing operations. To meet this need, we developed a novel method for representing document images in a parametric form. Like other “hybrid" image compression operations, the Contour Encoded Compression and Transmission (CECAT) system first divides images into foreground and background layers. The emphasis of this thesis revolves around improving the compression …

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Petrogenesis Of Eocene-Oligocene Magmatism Of The Sulphur Springs Range, Central Nevada: The Role Of Magma Mixing, Elizabeth Balls Ryskamp Nov 2006

Petrogenesis Of Eocene-Oligocene Magmatism Of The Sulphur Springs Range, Central Nevada: The Role Of Magma Mixing, Elizabeth Balls Ryskamp

Theses and Dissertations

Widespread base- and precious-metal anomalies, altered porphyry intrusions and oxidized veins occur in a portion of the Sulphur Springs Range, Nevada (adjacent to the Au-producing Carlin Trend). Some of the Eocene-Oligocene intrusions and cogenetic volcanic rocks in the range exhibit evidence of magma mixing and invite comparisons with other mineralized, Eocene mixed magma systems like the Bingham porphyry Cu deposit 300 km farther to the east. The Sulphur Springs igneous suite ranges compositionally through rhyolite, dacite, andesite and basaltic andesite but is less alkaline than the Bingham volcanic suite. However, the alkali content of the Sulphur Springs suite is similar …

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A Comparison Of Microarray Analyses: A Mixed Models Approach Versus The Significance Analysis Of Microarrays, Nathan Wallace Stephens Nov 2006

A Comparison Of Microarray Analyses: A Mixed Models Approach Versus The Significance Analysis Of Microarrays, Nathan Wallace Stephens

Theses and Dissertations

DNA microarrays are a relatively new technology for assessing the expression levels of thousands of genes simultaneously. Researchers hope to find genes that are differentially expressed by hybridizing cDNA from known treatment sources with various genes spotted on the microarrays. The large number of tests involved in analyzing microarrays has raised new questions in multiple testing. Several approaches for identifying differentially expressed genes have been proposed. This paper considers two: (1) a mixed models approach, and (2) the Signiffcance Analysis of Microarrays.

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A Performance Evaluation Of Dynamic Transport Switching For Multi-Transport Devices, Lei Wang Nov 2006

A Performance Evaluation Of Dynamic Transport Switching For Multi-Transport Devices, Lei Wang

Theses and Dissertations

Multi-transport devices are becoming more common, but sophisticated software is needed to fully realize the advantages of these devices. In this paper, we examine the performance of dynamic transport switching, which selects the best available transport for communication between two devices. We simulate transport switching within the Quality of Transport (QoT) architecture and show that it can effectively mitigate the effects of congestion and interference for connections between two multi-transport devices. We then evaluate dynamic transport switching overhead to characterize its effect on application throughput. Based on these insights, we identify several limitations of the QoT architecture and present solutions …

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