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Numerical Investigation Of Aeroelastic Mode Distribution For Aircraft Wing Model In Subsonic Air Flow, Marianna A. Shubov, Stephen B. Wineberg, Robert Holt 2010 University of New Hampshire

Numerical Investigation Of Aeroelastic Mode Distribution For Aircraft Wing Model In Subsonic Air Flow, Marianna A. Shubov, Stephen B. Wineberg, Robert Holt

Mathematics & Statistics Scholarship

In this paper, the numerical results on two problems originated in aircraft wing modeling have been presented. The first problem is concerned with the approximation to the set of the aeroelastic modes, which are the eigenvalues of a certain boundary-value problem. The affirmative answer is given to the following question: can the leading asymptotical terms in the analytical formulas be used as reasonably accurate description of the aeroelastic modes? The positive answer means that these leading terms can be used by engineers for practical calculations. The second problem is concerned with the flutter phenomena in aircraft wings in a subsonic ...


Ua1b1/1/2 An Evening With A Scientist And A Newspaper Man, WKU University Archives 2010 WKU University Archives

Ua1b1/1/2 An Evening With A Scientist And A Newspaper Man, Wku University Archives

WKU Archives Collection Inventories

Rodes-Helm lecture by Harry Gray and James Ausenbaugh entitled An Evening with A Scientist and a News Man moderated by Lowell Harrison. The lecture format allows each speaker 20 minutes to present his/her topic, response time to each other and ends with a question / answer session from the audience.

Dr. Harry Gray, a leading authority in the field of solar energym, fears that science is advancing so fast on so many fronts that the public can't keep up. More specifically, he worries that the news media's ability - or commitment - to help keep the public informed is limited ...


Finding Event-Specific Influencers In Dynamic Social Networks, Christopher Brendan Schenk 2010 University of Colorado at Boulder

Finding Event-Specific Influencers In Dynamic Social Networks, Christopher Brendan Schenk

Computer Science Graduate Theses & Dissertations

Reputation models are widely in use today in commercial transaction (ebay), product review (amazon, epinions), and news commentary websites (slashdot). The purpose of these reputation models is to provide behavioral or informational data for future users to determine whether or not he or she will trust the data. These models are dependent on explicit feedback mechanisms where users rate product, other users, or information. However, for many popular social network information sources on the web, no such explicit feedback systems exist where users rate information in order for consumers of this information to be able to judge the trustworthiness of ...


Speaking For The Trees: A New (Old) Approach To Languages And Syntax, Moss Prescott 2010 University of Colorado at Boulder

Speaking For The Trees: A New (Old) Approach To Languages And Syntax, Moss Prescott

Computer Science Graduate Theses & Dissertations

Programmers in many fields are interested in building new languages. In the same way that high-level languages increase productivity by allowing programmers to accomplish more with a given amount of code, a special-purpose language can reduce repetitive code and hide implementation detail, making a program's structure and function more evident. Sometimes an entire new language is called for, and other times an existing language serves most needs but could benefit from a few additional elements. However, current tools support this kind of extension poorly.

Language tools typically represent programs internally as trees which are easily extended with new types ...


Graph Connectivity: Approximation Algorithms And Applications To Protein-Protein Interaction Networks, Suzanne Renick Gallagher 2010 University of Colorado at Boulder

Graph Connectivity: Approximation Algorithms And Applications To Protein-Protein Interaction Networks, Suzanne Renick Gallagher

Computer Science Graduate Theses & Dissertations

A graph is connected if there is a path between any two of its vertices and k-connected if there are at least k disjoint paths between any two vertices. A graph is k-edge-connected if none of the k paths share any edges and k-vertex-connected (or k-connected) if they do not share any intermediate vertices. We examine some problems related to k-connectivity and an application.

We have looked at the k-edge-connected spanning subgraph problem: given a k-edge-connected graph, find the smallest subgraph that includes all vertices and is still k-edge-connected. We improved two algorithms for approximating solutions to this problem. The ...


Ambient Programming, Nwanua Onochie Elumeze 2010 University of Colorado at Boulder

Ambient Programming, Nwanua Onochie Elumeze

Computer Science Graduate Theses & Dissertations

Increasingly powerful and tiny electronics are finding their way into clothing, accessories, and everyday environments. It is becoming common to find computers in shoes, bracelets, hats, walls, pendants, and so on. However, the domain of computer programming has remained on the desktop: in order to customize their behavior, one must still connect these artifacts to a larger, general-purpose computer, ironically taking one out of the very physical context of use that ambient computing is intended for.

This document addresses the notion of end-user programmability of ambient artifacts. Specifically, it discusses how we may customize the behavior of a variety of ...


The Construction Of Meaning: The Role Of Context In Corpus-Based Approaches To Language Modeling, Praful Mangalath 2010 University of Colorado at Boulder

The Construction Of Meaning: The Role Of Context In Corpus-Based Approaches To Language Modeling, Praful Mangalath

Computer Science Graduate Theses & Dissertations

This dissertation presents a framework for statistically modeling words and sentences. It focuses on the role of context in learning semantic representations from a corpus. In recent years, approaches like Latent Semantic Analysis (LSA) (Deerwester et al., 1990; Landauer et al., 1997) and Probabilistic Topic Models (LDA) (Blei et al., 2003; Griffiths and Steyvers, 2002,2007; Hofmann, 1999) have both enjoyed success with the psycholinguistics community as being theories of meaning and models of language understanding. They serve as important components of information retrieval, machine translation, and document summarization systems, as well as in several other applications. However, sentences have ...


Computational Models Of Quality For Educational Digital Resource Assessment, Philipp Georg Wetzler 2010 University of Colorado at Boulder

Computational Models Of Quality For Educational Digital Resource Assessment, Philipp Georg Wetzler

Computer Science Graduate Theses & Dissertations

Educational digital libraries and peer-produced open educational resources have become integral to efforts to incorporate personalized learning into the classroom. Assuring the quality of educational content from these sources has become a major concern of the curators of such materials, and of educators who want to use them. But quality of educational materials is a multi-faceted problem, not completely understood, and often disputed. In current practice, focused manual effort by trained experts is required to assess each resource.

This work attempts to leverage the large existing corpus of work in the field of computational semantics to supplement and support human ...


Scalable Software Control Of Million-Element Cyber-Physical Systems Using A Graphics Processing Unit, Veljko Krunic 2010 University of Colorado Boulder

Scalable Software Control Of Million-Element Cyber-Physical Systems Using A Graphics Processing Unit, Veljko Krunic

Computer Science Graduate Theses & Dissertations

Cyber-Physical Systems consisting of hundreds of thousands of elements are emerging, with even bigger systems likely to emerge in the immediate future. However, in order for emerging and reasonably anticipated systems to be practical, the software control of million-element Cyber-Physical Systems needs to be addressed.

This PhD thesis describes the software control algorithms necessary for the realization of million-element Cyber-Physical Systems. This work will show that Graphics Processing Unit (GPU) based control of such Cyber-Physical Systems provides significant benefits, both in the form of fast control of large numbers of elements, as well as in terms of providing a viable ...


Improving Access To Space Weather Data Via Workflows And Web Services, Anu Swapna Sundaravel 2010 University of Colorado at Boulder

Improving Access To Space Weather Data Via Workflows And Web Services, Anu Swapna Sundaravel

Computer Science Graduate Theses & Dissertations

The Space Physics Interactive Data Resource (SPIDR) is a web-based interactive tool developed by NOAA’s National Geophysical Data Center to provide access to historical space physics datasets. These data sets are widely used by physicists for space weather modeling and predictions. Built on a distributed network of databases and application servers, SPIDR offers services in two ways: via a web page interface and via a web service interface. SPIDR exposes several SOAP-based web services that client applications implement to connect to a number of data sources for data download and processing. At present, the usage of the web services ...


High-Performance Word Sense Disambiguation With Less Manual Effort, Dmitriy Dligach 2010 University of Colorado, Boulder

High-Performance Word Sense Disambiguation With Less Manual Effort, Dmitriy Dligach

Computer Science Graduate Theses & Dissertations

Supervised learning is a widely used paradigm in Natural Language Processing. This paradigm involves learning a classifier from annotated examples and applying it to unseen data. We cast word sense disambiguation, our task of interest, as a supervised learning problem. We then formulate the end goal of this dissertation: to develop a series of methods aimed at achieving the highest possible word sense disambiguation performance with the least reliance on manual effort.

We begin by implementing a word sense disambiguation system, which utilizes rich linguistic features to better represent the contexts of ambiguous words. Our state-of-the-art system captures three types ...


Macs: A Practical Approach To Mobile Content Sharing Over Ad Hoc Networks, Thomas Kooh 2010 University of Colorado, Boulder

Macs: A Practical Approach To Mobile Content Sharing Over Ad Hoc Networks, Thomas Kooh

Computer Science Graduate Theses & Dissertations

Mobile phones are increasingly equipped with features that allow them to self-generate digital content, and they possess larger storage capacity. With the increased trend of information sharing, promoted by web2.0 applications and the success of peer-to-peer in the wired world, the ability for users to share content on their mobile devices is engaging. Most mobile content sharing solutions work over infrastructure-based networks, such as the internet or the mobile phone network. However, network connectivity is not always available or, at least, affordable. On the other hand, the proliferation of feature-rich mobile devices implies that a mass of digital content ...


Genetic Algorithms With Chaotic Population Dynamics, Thomas Harrison Nelson 2010 University of Colorado at Boulder

Genetic Algorithms With Chaotic Population Dynamics, Thomas Harrison Nelson

Computer Science Graduate Theses & Dissertations

In this thesis I demonstrate a novel application of chaotic dynamics to evolutionary algorithms, specifically in population size management. Typical evolutionary algorithms require a population size to be set as a parameter, which remains constant throughout execution. I created a new algorithm that can vary the population size chaotically or periodically, and do a series of performance tests comparing static, periodic, and chaotic population control. The problems targeted in these tests are chosen from both continuous and discrete multi-dimensional domains. I find that both chaotic and static population control perform well in certain situations; my evidence suggests that periodic population ...


Integrated Scheduling And Beam Steering For Spatial Reuse, Eric William Anderson 2010 University of Colorado, Boulder

Integrated Scheduling And Beam Steering For Spatial Reuse, Eric William Anderson

Computer Science Graduate Theses & Dissertations

This document describes an approach to integrating antenna selection and control into a time-division MAC scheduling process. I argue that through such integration it is possible to achieve greater spatial reuse and interference mitigation than by solving the two problems separately. Without coupling between the MAC scheduling and physical antenna configuration processes, a "chicken-and-egg" problem exists: If antenna decisions are made before scheduling, they cannot be optimized for the communication that will actually occur. If, on the other hand, the scheduling decisions are made first, the scheduler cannot know what the actual interference and communications properties of the network will ...


Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein 2010 Old Dominion University

Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein

Physics Faculty Publications

We report the first measurement of the transverse momentum dependence of double-spin asymmetries in semi-inclusive production of pions in deep-inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Jefferson Lab (JLab). Modulations of single spin asymmetries over the azimuthal angle between lepton scattering and hadron production planes ϕ have been measured over a wide kinematic range in Bjorken x and virtual photon squared four-momentum Q2. A significant nonzero sin2ϕ single spin asymmetry was observed for the first time indicating strong spin-orbit correlations ...


Exotic Species, Scott R. Abella 2010 University of Nevada, Las Vegas

Exotic Species, Scott R. Abella

Public Policy and Leadership Faculty Publications

No abstract provided.


Trying To Beat The Brome: Understanding Establishment Thresholds And Choosing Competitive Native Species At Parashant National Monument, Scott R. Abella, E. Cayenne Engel 2010 University of Nevada, Las Vegas

Trying To Beat The Brome: Understanding Establishment Thresholds And Choosing Competitive Native Species At Parashant National Monument, Scott R. Abella, E. Cayenne Engel

Public Policy and Leadership Faculty Publications

Desert fires fueled by exotic grasses like the omnipresent red brome (Bromus rubens) can be intense and cause widespread mortality of native vegetation. Native desert scrub communities such as those dominated by blackbrush (Coleogyne ramosissima) do not readily reestablish after fire (Abella 2009) and may even become more abundant in the post-burn landscape initiating a fire cycle that occurs at a greater frequency than the recovery time of the long-lived desert perennial community.


Undergraduate And Graduate Programs In Environmental Science At Unlv, Scott R. Abella 2010 University of Nevada, Las Vegas

Undergraduate And Graduate Programs In Environmental Science At Unlv, Scott R. Abella

Public Policy and Leadership Faculty Publications

The School of Environmental and Public Affairs at UNLV houses B.A. and B.S. degrees in Environmental Studies and M.S. and PhD degrees in Environmental Science. These degrees are flexible, multi-purpose, interdisciplinary programs that can be tailored for both breadth and depth.


Construction, Figures Of Merit And Testing Of A Single-Cell Fluorescence Excitation Spectroscopy System, Laura S. Hill, Tammi L. Richardson, Louisa T.M. Profeta, Timothy J. Shaw, Christopher J. Hintz, Benjamin S. Twining, Evelyn Lawrenz, Micheal L. Myrick 2010 University of South Carolina - Columbia

Construction, Figures Of Merit And Testing Of A Single-Cell Fluorescence Excitation Spectroscopy System, Laura S. Hill, Tammi L. Richardson, Louisa T.M. Profeta, Timothy J. Shaw, Christopher J. Hintz, Benjamin S. Twining, Evelyn Lawrenz, Micheal L. Myrick

Faculty Publications

Characterization of phytoplankton community composition is critical to understanding the ecology and biogeochemistry of the oceans. One approach to taxonomic characterization takes advantage of differing pigmentation between algal taxa and thus differences in fluorescence excitation spectra. Analyses of bulk water samples, however, may be confounded by interference from chromophoric dissolved organic matter or suspended particulate matter. Here, we describe an instrument that uses a laser trap based on a Nikon TE2000-U microscope to position individual phytoplankton cells for confocal fluorescence excitation spectroscopy, thus avoiding interference from the surrounding medium. Quantitative measurements of optical power give data in the form of ...


Crossed-Beams And Theoretical Studies Of Hyperthermal Reactions Of O(3p) With Hcl, Jianming Zhang, Amy L. Brunsvold, Hari P. Upadhyaya, Timothy K. Minton, Jon P. Camden, Sophya V. Garashchuk, George C. Schatz 2010 University of South Carolina - Columbia

Crossed-Beams And Theoretical Studies Of Hyperthermal Reactions Of O(3p) With Hcl, Jianming Zhang, Amy L. Brunsvold, Hari P. Upadhyaya, Timothy K. Minton, Jon P. Camden, Sophya V. Garashchuk, George C. Schatz

Faculty Publications

The reaction of O(3 P) with HCl at hyperthermal collision energies (45-116 kcal mol-1 ) has been investigated with crossed-molecular beams experiments and direct dynamics quasi-classical trajectory calculations. The reaction may proceed by two primary pathways, (1) H-atom abstraction to produce OH and Cl and (2) H-atom elimination to produce H and ClO. The H-atom abstraction reaction follows a stripping mechanism, in which the reagent O atom approaches the HCl molecule at large impact parameters and the OH product is scattered in the forward direction, defined as the initial direction of the reagent O atoms. The H-atom elimination reaction is ...


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