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Evolution Of The Band Structure Of Β-In2 S3−3x O3x Buffer Layer With Its Oxygen Content, N. Barreau, S. Marsillac, J. C. Bernède, L. Assmann

Electrical & Computer Engineering Faculty Publications

The evolution of the band structure of β-In2 S3−3x O3x (BISO) thin films grown by physical vapor deposition, with composition x, is investigated using x-ray photoelectron spectroscopy. It is shown that the energy difference between the valence-band level and the Fermi level remains nearly constant as the optical band gap of the films increases. As a consequence, the difference between the conduction band level and the Fermi level increases as much as the optical band gap of the films. The calculation of the electronic affinity [ ] of the BISO thin films shows that it decreases linearly from 4.65 …

Animation Studies, Disciplinarity And Discursivity, Paul Ward

Reconstruction: Studies in Contemporary Culture

[First paragraph]

Addressing how knowledge grows, develops and fits together is arguably one of the most testing tasks facing scholars. In a world where knowledge is increasingly viewed as a commodity -- and the teaching of that knowledge is often done in an instrumentalist fashion -- we need to come to a fuller understanding of how knowledge areas inter-relate. Such a mapping needs to move beyond simplistic models of disciplinarity (and its bolted-together variants, such as interdisciplinarity, multidisciplinarity, and the like) and explore the ways that a wide range of people in an equally diverse set of contexts might constitute …

Minutes Of The Virginia Academy Of Science Council Meeting- May 2002, Virginia Journal Of Science

Virginia Journal of Science

Full proceedings of the Council Meeting of the Virginia Academy of Science at Hampton University on May 24, 2002

Fuzzy System Identification Based Upon A Novel Approach To Nonlinear Optimization, Raymond Scott Starsman

Electrical & Computer Engineering Theses & Dissertations

Fuzzy systems are often used to model the behavior of nonlinear dynamical systems in process control industries because the model is linguistic in nature, uses a natural-language rule set, and because they can be included in control laws that meet the design goals. However, because the rigorous study of fuzzy logic is relatively recent, there is a shortage of well-defined and understood mechanisms for the design of a fuzzy system. One of the greatest challenges in fuzzy modeling is to determine a suitable structure, parameters, and rules that minimize an appropriately chosen error between the fuzzy system, a mathematical model, …

Measurement Of Proton Transfer Reaction Rates In A Microwave Cavity Discharge Flowing Afterglow, George M. Brooke Iv

Physics Theses & Dissertations

The reaction rate coefficients between the hydronium ion and the molecules ethene (C₂H₄), propene (C₃H₆), 1-butene (C₄H₈) and hydrogen sulfide (H₂S) were measured at 296 K. The measured reaction rates were compared to collision rates calculated using average dipole orientation (ADO) theory. Reaction efficiency depends primarily upon the proton affinity of the molecules. All the measurements were obtained using the newly developed microwave cavity discharge flowing afterglow (MCD-FA) apparatus. This device uses an Asmussen-type microwave cavity discharge ion source that is …

Coherent Backscattering Of Light From An Ultra Cold Gas Of Rubidium-85 Atoms, Pasad B. Kulatunga

Physics Theses & Dissertations

This thesis reports on the experimental study of coherent radiative transport in an ultracold gas of ⁸⁵Rb atoms confined in a magneto-optic trap. Measurements are made of the polarization dependence of the spatial and spectral profile of light backscattered from the sample. The results shows an interferometric enhancement sensitive to coherent multiple scattering in the atomic gas, and strong variations with the polarization of the incident and detected light. Effects due to coherent enhancement of weak non-resonant transitions are also observed. Comparison of the measurements with realistic quantum Monte Carlo simulations of Kupriyanov, et al [1] yield very good …

Measurments Of Correlated Pair Momentum Distributions In 3he(E,E'Pp)N With Clas, Rustam Niyazov

Physics Theses & Dissertations

We have measured the ³He(e,e'pp)n reaction at 2.2 and 4.4 GeV over a wide kinematic range. The kinetic energy distribution for ’fast’ nucleons (p > 250 MeV/c) peaks where two nucleons each have 20% or less and the third or ‘leading’ nucleon carries most of the transferred energy. These fast nucleon pairs (both pp and pn) are back-to-back and carry very little momentum along q, indicating that they are spectators. Experimental and theoretical evidence indicates that we have measured N N correlations in ³He(e,e'pp)n by striking the third nucleon and detecting the spectator correlated pair.

Modeling The Decision Process Of A Joint Task Force Commander, John Anthony Sokolowski

Computational Modeling & Simulation Engineering Theses & Dissertations

The U.S. military uses modeling and simulation as a tool to help meet its warfighting needs. A key element within military simulations is the ability to accurately represent human behavior. This is especially true in a simulation's ability to emulate realistic military decisions. However, current decision models fail to provide the variability and flexibility that human decision makers exhibit. Further, most decision models are focused on tactical decisions and ignore the decision process of senior military commanders at the operational level of warfare. In an effort to develop a better decision model that would mimic the decision process of a …

Multi-Symplectic Integrators For Nonlinear Wave Equations, Alvaro Lucas Islas

Mathematics & Statistics Theses & Dissertations

Symplectic (area-preserving) integrators for Hamiltonian ordinary differential equations have shown to be robust, efficient and accurate in long-term calculations. In this thesis, we show how symplectic integrators have a natural generalization to Hamiltonian PDEs by introducing the concept of multi-symplectic partial differential equations (PDEs). In particular, we show that multi-symplectic PDEs have an underlying spatio-temporal multi-symplectic structure characterized by a multi-symplectic conservation law MSCL). Then multi-symplectic integrators (MSIs) are numerical schemes that preserve exactly the MSCL. Remarkably, we demonstrate that, although not designed to do so, MSIs preserve very well other associated local conservation laws and global invariants, such as …

A Framework Of Cooperating Agents Hierarchies For Local-Area Mobility Support, Ayman Adel Abdel Hamid

Computer Science Theses & Dissertations

Host mobility creates a routing problem in the Internet, where an IP address reflects the network's point of attachment. Mobile IP, relying on a mapping between a home address and a care-of address, and a home registration process, is widely accepted as a solution for the host mobility problem in wide-area mobility scenarios. However, its home registration requirement, upon each change of point of attachment, makes it unsuitable to handle local-area mobility, resulting in large handoff latencies, increased packet loss, and disrupted services. In this dissertation, we introduce a local-area mobility support framework for IPv4 based on the deployment of …

Circulation, Vol. 10, No. 1, Center For Coastal Physical Oceanography, Old Dominion University, Thomas Royer

CCPO Circulation

Spring 2003 issue of CCPO Circulation featuring article "R/V Fay Slover Is Here" by Dr. Thomas Royer

Creating Enterprise Simulations Using High Level Architecture, Anton R. Lidums

Electrical & Computer Engineering Theses & Dissertations

Despite an established need, there are two remaining roadblocks to building distributed simulations and enterprise simulation systems. First, commercial simulation packages and engineering modeling tools are not readily distributable across multiple computers and have traditionally had very little impetus for utilizing a distributable format. Second, although HLA simulations have been built and there are tools to facilitate those efforts, very little has been done or written that specifically describes a "non-standard" integration implementation in sufficient detail to make the process reusable or repeatable. This thesis introduces a proof of concept prototype that was developed to integrate simulations. The paper presents …

Parallel Implementation Of A Face Recognition [Sic] System Based On Modular Pca Approach, Rajkiran Gottumukkal

Electrical & Computer Engineering Theses & Dissertations

This thesis describes research in automated methods for the recognition of human faces. The research is driven by the need to design a method, which would ensure high accuracy under the conditions of facial expression, illumination and pose variations. The resulting method is able to cope with uncontrolled nature of facial expression, illumination and head rotations. The main novelty of this work is the idea that some of the local facial features do not vary even when the facial expression, illumination and pose vary. This idea is applied to the existing principle component analysis lPCA) method to arrive at a …

Guided By God: The Catholic Church And Political Legitimacy In The Philippines, Steven B. Shirley

Graduate Program in International Studies Theses & Dissertations

The developing world is witnessing a growing (some may say disturbing) trend towards “de-secularization” of national governments. This trend has been understudied and misunderstood over the past decade. Government experts and scholars alike too often view this trend through the lens of “threat” analysis and in so doing miss key cultural, historical, and political factors at work. This study attempts to redress this problem. By looking at political legitimacy and the role religious organizations such as the Catholic Church may play, a new understanding of how religious institutions can shape and mold governments and policies emerges.

This study focuses specifically …

A Combinatorial Technique For Face Detection Based On Color And Statistical Analysis, Harishwaran Hariharan

Electrical & Computer Engineering Theses & Dissertations

Automatic detection of faces from video sequences is an important task in security applications. The number, location, size and orientation of human faces in a video frame are unpredictable and can vary from frame to frame. A face detection algorithm for color images in the presence of varying lighting conditions and complexity in background relying upon color and statistical analysis is presented in this thesis. The new method detects skin regions over the entire image and then classifies the skin regions as faces and non-faces. Segmentation of skin regions is performed by a novel color space merging procedure named Integrated …

Output Analysis Of Configurable Port Simulation, Ravikiran Jogu

Electrical & Computer Engineering Theses & Dissertations

The Configurable Port Simulation (CPortS) is a simulation of military cargo moving through a commercial seaport during a force deployment. CPortS simulates cargo at the individual entity level of detail. Simulation at the individual entity level generates huge amounts of output data making the output analysis difficult. To understand the reasons as to why bottlenecks occur in the process of cargo clearance, an analyst needs to be able to partition the data during analysis, not a priori. This makes the estimation of required graph generation impossible, which demands a very dynamic output analysis tool that can enable the analyst to …

Automatic Speaker Identification Using Reusable And Retrainable Binary-Pair Partitioned Neural Networks, Ashutosh Mishra

Electrical & Computer Engineering Theses & Dissertations

This thesis presents an extension of the work previously done on speaker identification using Binary Pair Partitioned (BPP) neural networks. In the previous work, a separate network was used for each pair of speakers in the speaker population. Although the basic BPP approach did perform well and had a simple underlying algorithm, it had the obvious disadvantage of requiring an extremely large number of networks for speaker identification with large speaker populations. It also requires training of networks proportional to the square of the number of speakers under consideration, leading to a very large number of networks to be trained …

A Pipelined Architecture For Real Time Correction Of Barrel Distortion In Wide-Angle Camera Images, Hau Trung Ngo

Electrical & Computer Engineering Theses & Dissertations

Images captured by wide-angle cameras show barrel type spatial distortion due to wide-angle configuration of the camera lens where image regions farther from the center are compressed in a nonlinear fashion. The barrel distortion correction technique based on least squares estimation attempts to correct a distorted image by expanding it nonlinearly so that straight lines in the object space remain straight in the image space. The intensity value of a pixel in the expanded image is calculated by back mapping its position to the corresponding position in the distorted image and performing linear interpolation on the neighboring pixels. Distorted images …

Analysis Of Ingaassb/Aigaassb Photodetectors For Applications At The 2.0 Micron Wavelengths, Phani Pendyala

Electrical & Computer Engineering Theses & Dissertations

The study of an InGaAsSb-based heterojunction avalanche photo detector has been carried out for 2-μm applications. A separate absorption and multiplication structure was used because it minimizes the tunneling component of the dark current in the absorption region, and also provides single-carrier injection into the multiplication region. This is a well-known requirement for reducing the multiplication noise. The primary goal was to evaluate the potential of InGaAsSb-AlGaAsSb photo-detectors for photodetection at the two-micron wavelength.

InGaAsSb is a relatively new material, and, therefore, characterization and photodetector response analysis based on this material are not available in the literature. In this thesis …

Two Dimensional Numerical Simulation Of Highly-Strained Hydrogen-Air Opposed Jet Laminar Diffusion Flames, Kyu C. Hwang

Mechanical & Aerospace Engineering Theses & Dissertations

In this study, a detailed 2-D numerical technique is utilized to investigate the structure, and flame extinction and restoration characteristics of laminar hydrogen-air opposed jet diffusion flames, using both plug (uniform) and parabolic inflow boundary conditions for 3 millimeter jet tubes, spaced 6 millimeters apart and imbedded in low velocity coflows.

First, by using the most recent of two chemical kinetic models, excellent agreement was obtained between calculated distributions of temperature and major species, and published UV laser Raman scattering measurements, for 50% and 100% hydrogen-air flames over a range of input strain rates. Agreement with measured OH profiles was …

Numerical Studies On Supersonic Mixing And Combustion Phenomena, Tarek M. Abdel-Salam

Mechanical & Aerospace Engineering Theses & Dissertations

A numerical study is conducted to investigate the mixing, combustion, and flow characteristics of different scramjet-combustor configurations. Three-dimensional models for the combustors have been used. Numerical results are obtained using a finite volume computational fluid dynamics (CFD) code with unstructured grids with sizes between 200,000 and 400,000 cells.

In the first part of the current study, the effects of the side angle of the fuel injectors in both mixing and combustion processes are investigated. Raised (compression) and relieved (expansion) wall-mounted ramps are used with side angles of 0 (unswept), 5, and 10 degrees. Results are obtained for nonreacting flows as …

Field Emission Based Sensors Using Carbon Nanotubes, Changkun Dong

Physics Theses & Dissertations

A number of sensitive applications would be greatly benefited by the development of better cold cathodes that employ the electron field emission process. Among the many kinds of field emitters that could be tried, carbon nanotubes (CNT) have a number of distinct advantages because of their unique geometrical structure, chemical inertness, mechanical stiffness, and high thermal and electrical conductivities. This dissertation describes research in which CNT cathodes were fabricated and their emission characteristics were measured.

Multi-walled carbon nanotubes (MWNT) were grown by chemical vapor deposition (CVD) on various substrates: Ni and Hastelloy gauze, 304 stainless steel (SS) plates, and Ni-coated …

Implementation And Testing Of Unsteady Reynolds-Averaged Navier-Stokes And Detached Eddy Simulation Using An Implicit Unstructured Multigrid Scheme, Juan A. Palaez

Mechanical & Aerospace Engineering Theses & Dissertations

Investigation and development of the Detached Eddy Simulation (DES) technique for the computation of unsteady flows on unstructured grids are presented. The motivation of the research work is driven by the ultimate goal of predicting separated flows of aerodynamic importance, such as massive stall or flows over complex non-streamlined geometries. These cases, in which large regions of massively separated flow are present, represent a challenge for conventional Unsteady Reynolds-Averaged Navier-Stokes (URANS) models, that in many cases, cannot produce solutions accurate enough and/or fast enough for industrial design and applications. A Detached Eddy Simulation model is implemented and its performance compared …

Dynamics Of Phase Transitions On Low-Index Metal Surfaces, Bo Lin

Electrical & Computer Engineering Theses & Dissertations

The surface superheating and phase transitions at the low-index surface of metal were investigated using conventional continuous and 100-ps time-resolved reflection high-energy electron diffraction. Three metal surfaces, In(111), Au(110) and Pb(111), have been investigated in this work. The high temperature behavior of the In(111) surface was investigated using reflection high-energy electron diffraction with 100-ps temporal resolution. The change of surface vacancy density on In(111) is observed from 300 K to near the bulk melting point. The vacancy-formation energy of In(111) surface is estimated from experimental results. The surface vacancy density is observed to increase with temperature; however, the average random …

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane

Status and Trends for Virginia Chesapeake Bay

This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane

Status and Trends for Virginia Chesapeake Bay

This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane

Status and Trends for Virginia Chesapeake Bay

This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …

Common Data Administration, Data Management, And Data Alignment As A Necessary Requirement For Coupling C4isr Systems And M&S Systems, Andreas Tolk

Computational Modeling & Simulation Engineering Faculty Publications

Within the application domain of military simulation systems, training and exercises as well as support to real operations require the coupling of the simulation system delivering the needed functionality with the Command, Control, Computing, Communications, Intelligence, Surveillance, and Reconnaissance (C4ISR) system providing the necessary data. The solution to this challenge is to build appropriate interfaces. Although in long term a more integrated approach will be necessary, in short and mid term, gateways and interfaces are likely to remain the standard. However, in order to succeed with the respective efforts, at least on the data level of interoperability, a common solution …

Early Intervention With Children At Risk Of Emotional/Behavioral Disorders: A Critical Examination Of Research Methodology And Practices, Peggy P. Hester, Heather M. Baltodano, Robert A. Gable, Stephen W. Tonelson, Jo M. Hendrickson

Communication Disorders & Special Education Faculty Publications

Children's behavior problems pose challenges to families, schools, and society. The research literature argues that early detection/intervention is the most powerful course of action in ameliorating these problems in children at risk of emotional/behavioral disorders. However, specifying precisely what constitutes a quality program of early intervention is not a simple task. Current conceptualizations suggest that successful early intervention cannot be unidimensional in nature, but must consist of a complex series of interactions and transactions that synergistically serve to nurture and enhance both the development of the child and family. In this paper, we reviewed the accumulated research to learn more …

Jsb Composability And Web Services Interoperability Via Extensible Modeling & Simulation Framework (Xmsf), Model Driven Architecture (Mda), Component Repositories, And Web-Based Visualization, Don Brutzman, Andreas Tolk

Computational Modeling & Simulation Engineering Faculty Publications

"Study Report prepared for the U. S. Air Force, Joint Synthetic Battlespace Analysis of Technical Approaches (ATA) Studies & Prototyping"

Overview: This paper summarizes research work conducted by organizations concerned with interoperable distributed information technology (IT) applications, in particular the Naval Postgraduate School (NPS) and Old Dominion University (ODU). Although the application focus is distributed modeling & simulation (M&S) the results and findings are in general easily applicable to other distributed concepts as well, in particular the support of operations by M&S applications, such as distributed mission operations. The core idea of this work is to show the necessity of …