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2007

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Sepc2007, Robert Kelly Sep 2007

Sepc2007, Robert Kelly

Robert Kelly Manuscripts

From September 2007 Robert Kelly Archive.

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Paving Hessenberg Varieties By Affines, Julianna S. Tymoczko Sep 2007

Paving Hessenberg Varieties By Affines, Julianna S. Tymoczko

Mathematics Sciences: Faculty Publications

Regular nilpotent Hessenberg varieties form a family of subvarieties of the flag variety arising in the study of quantum cohomology, geometric representation theory, and numerical analysis. In this paper we construct a paving by affines of regular nilpotent Hessenberg varieties for all classical types, generalizing results of De Concini-Lusztig-Procesi and Kostant. This paving is in fact the intersection of a particular Bruhat decomposition with the Hessenberg variety. The nonempty cells of the paving and their dimensions are identified by combinatorial conditions on roots. We use the paving to prove these Hessenberg varieties have no odd-dimensional homology.

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3d Simulation Of Cracks And Fractures In A Molecular Solid Under Stress And Compression, Mark Korlie Sep 2007

3d Simulation Of Cracks And Fractures In A Molecular Solid Under Stress And Compression, Mark Korlie

Department of Mathematics Faculty Scholarship and Creative Works

Using molecular mechanics, we study the evolution and propagation of cracks and fractures in a three-dimensional molecular sheet of ice under stress and compression. We use an approximate 6-12 Lennard-Jones potential for a pair of ice molecules to derive dynamical equations for the ice molecules in the solid. The resulting systems of nonlinear ordinary differential equations are then used to simulate the evolution and propagation of cracks and fractures in the solid. In the computer examples, we compare dynamical responses when the solid sheet of ice has a slot or does not have a slot. The mechanisms for development of …

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Acoustic Positioning And Tracking In Portsmouth Harbour, New Hampshire, Michelle Weirathmueller, Thomas C. Weber, Val E. Schmidt, Glenn Mcgillicuddy, Larry A. Mayer, Lloyd C. Huff Sep 2007

Acoustic Positioning And Tracking In Portsmouth Harbour, New Hampshire, Michelle Weirathmueller, Thomas C. Weber, Val E. Schmidt, Glenn Mcgillicuddy, Larry A. Mayer, Lloyd C. Huff

Center for Coastal and Ocean Mapping

Portsmouth Harbor, New Hampshire, is frequently used as a testing area for multibeam and sidescan sonars, and is the location of numerous ground-truthing studies. Having the ability to accurately position underwater sensors is an important aspect of this type of work. However, underwater positioning in Portsmouth Harbor is challenging. It is relatively shallow, approximately one kilometer wide with depths of less than 25 meters. There is mixing between fresh river water and seawater, which is intensified by high currents and strong tides. This causes a very complicated spatial and temporal sound speed structure. Solutions that use the time-of-arrival of an …

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Enhancement Of Underwater Video Mosaics For Post-Processing, Yuri Rzhanov, Fan Gu Sep 2007

Enhancement Of Underwater Video Mosaics For Post-Processing, Yuri Rzhanov, Fan Gu

Center for Coastal and Ocean Mapping

Mosaics of seafloor created from still images or video acquired underwater have proved to be useful for construction of maps of forensic and archeological sites, species' abundance estimates, habitat characterization, etc. Images taken by a camera mounted on a stable platform are registered (at first pair-wise and then globally) and assembled in a high resolution visual map of the surveyed area. While this map is usually sufficient for a human orientation and even quantitative measurements, it often contains artifacts that complicate an automatic post-processing (for example, extraction of shapes for organism counting, or segmentation for habitat characterization). The most prominent …

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Book Review: Moore On Mercury: The Planet And The Missions, T. D. Oswalt Sep 2007

Book Review: Moore On Mercury: The Planet And The Missions, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Moore on Mercury : the Planet and the Missions by Patrick Moore. Springer, 2006 139p, 1846282578 $29.95, 9781846282577 $29.95

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The Turn In Economics And The Turn In Economic Methodology, John B. Davis Sep 2007

The Turn In Economics And The Turn In Economic Methodology, John B. Davis

Economics Faculty Research and Publications

No abstract provided.

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Using Denovo Programming In Developing Water Networks Under Multi Criteria Decision Making, Abbas Husayn Batikh, Faten Farouk Albadri, Faris M. Alwan Sep 2007

Using Denovo Programming In Developing Water Networks Under Multi Criteria Decision Making, Abbas Husayn Batikh, Faten Farouk Albadri, Faris M. Alwan

Journal of Economics and Administrative Sciences

The object of this study is to establish a global model to use of DeNovo programming the strategies of multi-Decision making process in the city of Baghdad. Thus, we have chosen an important and an effective subject in the life of the citizen due to the importance of this subject in the Iraqi citizen of luck of water and for many reasons. In this thesis, we have tackled the establishment of a global model to be able to reach solution or an alternative model a money the available alternative. The alternative proposed here utilizes the application of the (DeNovo) programming …

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Comparison Between Ordinary Method And Robust Method To Estimate The Parameters Of The Univariate Mixed Model With Low Order, Abdul Majeed Hamza Al-Nasser, Safaa Younus Saffawi Sep 2007

Comparison Between Ordinary Method And Robust Method To Estimate The Parameters Of The Univariate Mixed Model With Low Order, Abdul Majeed Hamza Al-Nasser, Safaa Younus Saffawi

Journal of Economics and Administrative Sciences

A condense study was done to compare between the ordinary estimators. In particular the maximum likelihood estimator and the robust estimator, to estimate the parameters of the mixed model of order one, namely ARMA(1,1) model. Simulation study was done for a varieties the model. using: small, moderate and large sample sizes, were some new results were obtained. MAPE was used as a statistical criterion for comparison.

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Raman Fiber Lasers And Amplifiers Based On Multimode Fibers And Their Applications To Beam Cleanup, Nathan B. Terry Sep 2007

Raman Fiber Lasers And Amplifiers Based On Multimode Fibers And Their Applications To Beam Cleanup, Nathan B. Terry

Theses and Dissertations

Raman fiber lasers (RFLs) and Raman fiber amplifiers (RFAs) in multimode fibers were explored. The RFL based on a graded-index fiber was shown to be very efficient relative to RFLs based on singlemode fibers. Several configurations of the RFL were examined; the beam quality of the Stokes beam depended on the reflectivity of the output coupler and the Stokes power. When used as a beam combiner, the RFL was a highly efficient brightness converter. RFL configurations which used dichroic mirrors were shown to be potentially useful for RFLs based on very large fibers. The forward- and backward-seeded geometries of an …

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Polarimeter Blind Deconvolution Using Image Diversity, David M. Strong Sep 2007

Polarimeter Blind Deconvolution Using Image Diversity, David M. Strong

Theses and Dissertations

This research presents an algorithm that improves the ability to view objects using an electro-optical imaging system with at least one polarization sensitive channel in addition to the primary channel. An innovative algorithm for detection and estimation of the defocus aberration present in an image is also developed. Using a known defocus aberration, an iterative polarimeter deconvolution algorithm is developed using a generalized expectation-maximization (GEM) model. The polarimeter deconvolution algorithm is extended to an iterative polarimeter multiframe blind deconvolution (PMFBD) algorithm with an unknown aberration. Using both simulated and laboratory images, the results of the new PMFBD algorithm clearly outperforms …

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Energy-Efficient Querying Of Wireless Sensor Networks, Christopher R. Mann Sep 2007

Energy-Efficient Querying Of Wireless Sensor Networks, Christopher R. Mann

Theses and Dissertations

Due to the distributed nature of information collection in wireless sensor networks and the inherent limitations of the component devices, the ability to store, locate, and retrieve data and services with minimum energy expenditure is a critical network function. Additionally, effective search protocols must scale efficiently and consume a minimum of network energy and memory reserves. A novel search protocol, the Trajectory-based Selective Broadcast Query protocol, is proposed. An analytical model of the protocol is derived, and an optimization model is formulated. Based on the results of analysis and simulation, the protocol is shown to reduce the expected total network …

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Unreliable Retrial Queues In A Random Environment, James D. Cordeiro Jr. Sep 2007

Unreliable Retrial Queues In A Random Environment, James D. Cordeiro Jr.

Theses and Dissertations

This dissertation investigates stability conditions and approximate steady-state performance measures for unreliable, single-server retrial queues operating in a randomly evolving environment. In such systems, arriving customers that find the server busy or failed join a retrial queue from which they attempt to regain access to the server at random intervals. Such models are useful for the performance evaluation of communications and computer networks which are characterized by time-varying arrival, service and failure rates. To model this time-varying behavior, we study systems whose parameters are modulated by a finite Markov process. Two distinct cases are analyzed. The first considers systems with …

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A Framework For Analyzing And Mitigating The Vulnerabilities Of Complex Systems Via Attack And Protection Trees, Kenneth S. Edge Sep 2007

A Framework For Analyzing And Mitigating The Vulnerabilities Of Complex Systems Via Attack And Protection Trees, Kenneth S. Edge

Theses and Dissertations

Attack trees have been developed to describe processes by which malicious users attempt to exploit or break complex systems. Attack trees offer a method of decomposing, visualizing, and determining the cost or likelihood of attacks. Attack trees by themselves do not provide enough decision support to system defenders. This research develops the concept of using protection trees to offer a detailed risk analysis of a system. In addition to developing protection trees, this research improves the existing concept of attack trees and develops rule sets for the manipulation of metrics used in the security of complex systems. This research specifically …

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Flight Dynamic Response Of Hale Aircraft To Kc-135 Flowfield, Amanda J. Devuono Sep 2007

Flight Dynamic Response Of Hale Aircraft To Kc-135 Flowfield, Amanda J. Devuono

Theses and Dissertations

This research effort examines the static effects of a KC-135 flowfield on a flexible winged Sensorcraft model. The KC-135 flowfield data is generated by a vortex lattice code and integrated into Sensorcraft model for analysis. Building on previous research, a refueling situation was modeled to note the effects of the Sensorcraft at varying locations within the flowfield. The Sensorcraft model was analyzed for both rigid and flexible wings as a means of comparision. Flowfield locations of interest were determined and trimmed conditions were computed for each flowfield location. Utilizing the trimmed condition and flowfield locations, the nonlinear set of EOM's …

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Parallelization Of Ant Colony Optimization Via Area Of Expertise Learning, Adrian A. De Freitas Sep 2007

Parallelization Of Ant Colony Optimization Via Area Of Expertise Learning, Adrian A. De Freitas

Theses and Dissertations

Ant colony optimization algorithms have long been touted as providing an effective and efficient means of generating high quality solutions to NP-hard optimization problems. Unfortunately, while the structure of the algorithm is easy to parallelize, the nature and amount of communication required for parallel execution has meant that parallel implementations developed suffer from decreased solution quality, slower runtime performance, or both. This thesis explores a new strategy for ant colony parallelization that involves Area of Expertise (AOE) learning. The AOE concept is based on the idea that individual agents tend to gain knowledge of different areas of the search space …

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Scaling Ant Colony Optimization With Hierarchical Reinforcement Learning Partitioning, Erik J. Dries Sep 2007

Scaling Ant Colony Optimization With Hierarchical Reinforcement Learning Partitioning, Erik J. Dries

Theses and Dissertations

This research merges the hierarchical reinforcement learning (HRL) domain and the ant colony optimization (ACO) domain. The merger produces a HRL ACO algorithm capable of generating solutions for both domains. This research also provides two specific implementations of the new algorithm: the first a modification to Dietterich's MAXQ-Q HRL algorithm, the second a hierarchical ACO algorithm. These implementations generate faster results, with little to no significant change in the quality of solutions for the tested problem domains. The application of ACO to the MAXQ-Q algorithm replaces the reinforcement learning, Q-learning and SARSA, with the modified ant colony optimization method, Ant-Q. …

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Multi-Objective Optimization For Speed And Stability Of A Sony Aibo Gait, Christopher A. Patterson Sep 2007

Multi-Objective Optimization For Speed And Stability Of A Sony Aibo Gait, Christopher A. Patterson

Theses and Dissertations

Locomotion is a fundamental facet of mobile robotics that many higher level aspects rely on. However, this is not a simple problem for legged robots with many degrees of freedom. For this reason, machine learning techniques have been applied to the domain. Although impressive results have been achieved, there remains a fundamental problem with using most machine learning methods. The learning algorithms usually require a large dataset which is prohibitively hard to collect on an actual robot. Further, learning in simulation has had limited success transitioning to the real world. Also, many learning algorithms optimize for a single fitness function, …

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Collaborative, Trust-Based Security Mechanisms For A National Utility Intranet, Gregory M. Coates Sep 2007

Collaborative, Trust-Based Security Mechanisms For A National Utility Intranet, Gregory M. Coates

Theses and Dissertations

This thesis investigates security mechanisms for utility control and protection networks using IP-based protocol interaction. It proposes flexible, cost-effective solutions in strategic locations to protect transitioning legacy and full IP-standards architectures. It also demonstrates how operational signatures can be defined to enact organizationally-unique standard operating procedures for zero failure in environments with varying levels of uncertainty and trust. The research evaluates layering encryption, authentication, traffic filtering, content checks, and event correlation mechanisms over time-critical primary and backup control/protection signaling to prevent disruption by internal and external malicious activity or errors. Finally, it shows how a regional/national implementation can protect private …

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The Effects Of Signal And Image Compression Of Sar Data On Change Detection Algorithms, Kiran Shenoy Sep 2007

The Effects Of Signal And Image Compression Of Sar Data On Change Detection Algorithms, Kiran Shenoy

Theses and Dissertations

With massive amounts of SAR imagery and data being collected, the need for effective compression techniques is growing. One of the most popular applications for remote sensing is change detection, which compares two geo-registered images for changes in the scene. While lossless compression is needed for signal compression, the same is not often required for image compression. In almost every case the compression ratios are much higher in lossy compression making them more appealing when bandwidth and storage becomes an issue. This research analyzes different types of compression techniques that are adapted for SAR imagery, and tests these techniques with …

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Navigation Using Orthogonal Frequency Division Multiplexed Signals Of Opportunity, Jamie S. Velotta Sep 2007

Navigation Using Orthogonal Frequency Division Multiplexed Signals Of Opportunity, Jamie S. Velotta

Theses and Dissertations

The global positioning system (GPS) provides high-accuracy position measurements anywhere in the world. However, a limitation of this system is that a line of sight to multiple satellites is required; therefore, it is unsuitable to use indoors or in urban canyons. Also, in the presence of radio-frequency interference or jamming, GPS may be unavailable. Alternative methods of navigation and positioning are need to either compliment GPS as a backup or for use in areas unreachable by satellites. This research analyzes a feature-based correlation approach for determining reception differences between two Orthogonal Frequency Division receivers for the purpose of TDOA calculations. …

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An Instructional Strategy For Pictorial Drawing, James L. Mohler Sep 2007

An Instructional Strategy For Pictorial Drawing, James L. Mohler

Journal of STEM Teacher Education

This contribution presents two major findings from a qualitative investigation into spatial ability. The elicited data suggested that one of the significant differences between individuals identified as high and low in spatial ability was their decomposition skill relative to spatial problems. Also revealing was the impact of frustration and anxiety on spatial functioning. The author discusses an instructional strategy for pictorial drawing that appeared effective for individuals solving pictorial drawing problems.

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Usd Magazine Fall 2007, University Of San Diego Sep 2007

Usd Magazine Fall 2007, University Of San Diego

University of San Diego Magazine (1992- )

Contents; Editorial License; Letters to the Editor; Around the Park; Torero Athletics; Point of View; Connected by the Vine; Life in the City; Sacred Heart Still Beats; Alumni Update; Class Notes; USD Reflection

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The Development Of A Quantum Dot Solar Concentrator, Brenda Rowan Sep 2007

The Development Of A Quantum Dot Solar Concentrator, Brenda Rowan

Doctoral

The aim of this study was to investigate the feasibility of Quantum Dot Solar Concentrators (QDSCs). Quantum Dots offer the advantages of having broad absorption specr4a, tunable emission and improved stability. A range of Cadmium Selenide/|Zince Sulphide Quantum Dots were characterized in solution and composite form using time-resolved and steady state spectroscopie techniques and the stability of the composite samples was investigated over a 6 month period. A number of matrix materials were compared and the most suitable type for fabrication of QDSCs were identified. Techniques for fabrication and characterization of QDSCs were developed and a range of different QDSC …

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Earmstrong, Armstrong Atlantic State University Sep 2007

Earmstrong, Armstrong Atlantic State University

Armstrong News & Publications: e-Armstrong Newsletter (Archived)

No abstract provided.

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Onset Of Hearing Loss, Gender And Self Concept As Determinants Of Academic Achievements In English Language Of Students With Hearing Disability In Oyo State, Nigeria, J. Abiola Ademokoya, B. A. Shittu Sep 2007

Onset Of Hearing Loss, Gender And Self Concept As Determinants Of Academic Achievements In English Language Of Students With Hearing Disability In Oyo State, Nigeria, J. Abiola Ademokoya, B. A. Shittu

Essays in Education

Since every class of students with hearing disability is always a heterogeneous one, the need for establishing relationship between some intrinsic factors in these students and their academic achievements becomes very imperative. This study therefore examined the influence of onset of hearing loss, gender and self concept on their academic performance in English language. 100 Senior Secondary School class III students with hearing disability were purposively selected to participate in the study. The study also raised 3 hypotheses to ascertain relationships between onset of hearing loss, gender, and self concept and English language achievement. Instruments such as the self concept …

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Teacher Candidates’ Emerging Perceptions Of Reader Response Theory, Khaled Alazzi Sep 2007

Teacher Candidates’ Emerging Perceptions Of Reader Response Theory, Khaled Alazzi

Essays in Education

What are the possibilities when teacher candidates participate in focused instruction in reader response theory and connected opportunities to experience response to literature, then design and implement response experiences with their elementary students? Consideration of this question led to this study that describes teacher candidates’ knowledge about reader response theory and their perceptions of the value and usefulness of reader response theory throughout a semester of focused experiences in university and elementary classrooms. Through qualitative analysis, four distinct, but related themes emerged. These themes describe teacher candidates who: 1) are at differing stages of understanding, 2) find that responding to …

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A New University Supervisor: Their Experiences And Enrichment, Lane Andrew Sep 2007

A New University Supervisor: Their Experiences And Enrichment, Lane Andrew

Essays in Education

For various reasons, graduate students often hold the position of university supervisor. Because this population graduates every few years, first time supervisors are relatively common. In this qualitative case study, I explore the experiences of one graduate student who has just completed a supervisory assignment for the first time. Instead of focusing on the interpersonal dynamics of the supervisor’s experiences, the results of this study focus on the supervisor’s experiences of being in a position of authority, applying academic knowledge to practice, and understanding and interpreting professional standards into the context of the classroom. Another aspect that is explored is …

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Intellectually Retarded Education In Nigeria: Past, Present, And Future, Dada Olubukola Sep 2007

Intellectually Retarded Education In Nigeria: Past, Present, And Future, Dada Olubukola

Essays in Education

Historically, the persons with intellectual retardation have been neglected in most cultures. In our African culture for instance families were concerned about their image in the society. So, they manage to hide their retarded members in the home environment. Today, the education of the intellectually retarded has recorded significant achievement despite the undeniable successes education of children with intellectual retardation is still being hindered by social prejudices and discriminations. This paper highlights the myriads of obstacles and challenges facing their education. The presenter therefore recommends way to improve the quality of their education for the future.

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Complexity And Chaos Theories As Metaphoric Lenses: An Alternative In Exploring The Voices Of Marginalized Populations, Dannielle Joy Davis Sep 2007

Complexity And Chaos Theories As Metaphoric Lenses: An Alternative In Exploring The Voices Of Marginalized Populations, Dannielle Joy Davis

Essays in Education

Through the metaphoric lenses of complexity and chaos theories, the Committee on Institutional Cooperation’s (CIC) Summer Research Opportunity Program (SROP) is evaluated in terms of its breadth of influence within and without institutional walls, as well as social dogma that pervades this program and its various host institutions. Application of these theories as metaphoric lenses, unveil patterns of influence and dogma at both programmatic and individual levels. Such an application promises to assist in understanding the effectiveness of the SROP program. For decades, minority enrichment programs have sought to promote equity within education through programs such as SROP. By examining …

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