853 Works

A Generalization of Linear Multistep Methods

Leon Arriola
A generalization of the methods that are currently available to solve systems of ordinary differential equations is made. This generalization is made by constructing linear multistep methods from an arbitrary set of monotone interpolating and approximating functions. Local truncation error estimates as well as stability analysis is given. Specifically, the class of linear multistep methods of the Adams and BDF type are discussed.

Parallel-Vector Computation for Geometrically Nonlinear Frame Structural Analysis and Design Sensitivity Analysis

Majdi A. Baddourah
Parallel-vector algorithms are presented for solving the geometrically nonlinear structural problems and obtaining design sensitivity information. A new algorithm is also presented for parallel generation and assembly of the finite element stiffness and mass matrices. The presented assembly algorithm is based on a node-by-node approach rather than the more conventional element-by-element approach. Three different methods, Newton Raphson, Modified Newton Raphson, and the BFGS, are used in the analysis of the nonlinear structural problems. A study...

Elementary Guidance Services in Urban and Rural Schools in Tidewater, Virginia

Berkley Edgerton Ashby
The purpose of this study was to assess the relative importance of the ten most significant components of an elementary guidance program. A second purpose was to identify differences in guidance services provided in selected urban and rural schools and also the perceived effectiveness and adequacy of the services as viewed by counselors and teachers. The study was conducted with elementary guidance counselors and elementary teachers in 48 urban and 48 rural schools in Tidewater,...

The Effects of an Inservice Training Program for Cooperating Teachers on the Supervision of Student Teachers in an Urban School System

Cheryl S. Baker
The primary task of this research was to develop, implement, and evaluate an inservice training program designed to provide cooperating teachers with supervisory skills. The research design employed to evaluate this study utilized both quantitative and qualitative methods and procedures. Quantitative methods included a quasi-experimental design with the inservice training program as the independent variable and the posttest measure of cooperating teacher effectiveness as the dependent variable. Participants in the investigation were 42 student teacher...

The Effects of Human-Computer Communication Mode, Task Complexity, and Desire for Control on Performance and Discourse Organization in an Adaptive Task

Cristina Bubb-Lewis
The present study examined how different communication patterns affected task performance with an adaptive interface. A Wizard-of-Oz simulation (Gould, Conti, & Hovanyecz, 1983) was used to create the impression of a talking and listening computer that acted as a teammate to help participants interact with a computer application. Four levels of communication mode were used which differed in the level of restriction placed on human-computer communication. In addition, participants completed two sets of tasks (simple...

African-American Males' Perception of Law Enforcement: A Psychophysiological Perspective

Adolph Brown III
This study compared the psychophysiological reactivity of African American and European American males to authority. Nineteen African American males and 23 European American males were randomly assigned to either be interrogated by a police officer, or see a police officer interrogate that experimenter or view a videotape of police activity. Participants' physiological reactivity, acceptance of authority, fear of negative evaluation or social anxiety, and apprehension and anxiety in stressful situations as well as EMG, SCR,...

Three-Dimensional Aerodynamic Shape Optimization Using Discrete Sensitivity Analysis

Gregory Wayne Burgreen
An aerodynamic shape optimization procedure based on discrete sensitivity analysis is extended to treat three-dimensional geometries. The function of sensitivity analysis is to directly couple computational fluid dynamics (CFD) with numerical optimization techniques, which facilitates the construction of efficient direct-design methods. The development of a practical three-dimensional design procedures entails many challenges, such as: (1) the demand for significant efficiency improvements over current design methods; (2) a general and flexible three-dimensional surface representation; and (3)...

Experimental Investigation of a Non-Thermal Atmospheric Pressure Plasma Jet

Asma Begum
The main objective of this dissertation is to understand the formation of the plasma jet from the plasma pencil, and the propagation of the plasma jet in the ambient atmosphere where the effect of the external electric field is almost zero. Before investigating the formation and propagation phenomenon of the plasma jet, common physical properties of plasma jets are determined by using the imaging technique and optical emission spectroscopy. The first goal of this dissertation...

Globalization and the Paradox of Incorporation and Marginalization: An Exploratory Note on Sub-Saharan Africa

Charles R. Lartey
Globalization has of late become the lingua franca of the study of the international political economic system. As its ideological counterpart, globalization has elevated neoliberalism to the status of an international theology. To harness the benefits of a globalizing world economy, conventional wisdom consider the dictums underlying neoliberal policies as “immutable laws” that must be adopted by both the developing and the developed world. Utilizing a structured, focused analysis based on a case study of...

Multidimensional Approach to Implementation of Continuous Process Improvement Utilizing Small Run Analysis in a Shipyard Environment

Paul Ray Hollandsworth
Nationally, both public and private shipyards are experiencing a high rework rate (over 40%) in the fabrication of plug connectors used for electronic systems onboard Navy vessels. The shipyard's survival depends on acquiring the elements necessary to maintain a major industry in a position of continuous improvement that produces a better product than their competitors, at less cost, in a safe manner, and on schedule. This research addresses the complex problem of how to introduce...

Multi-National Project Team Communications and Cultural Influences

Morgan E. Henrie
This exploratory case study dissertation examined multinational project teams' communication satisfaction as influenced by the project team's cultural attribute of power distance. Utilizing a exploratory case study, semi-guided interview research approach, ordinal scale data and open-ended contextual based question responses was obtained. This data was gathered from United States---Russia and Canada---Angola multi-national, complex, high technology oil transportation project teams. Triangulation data gathering techniques were utilized to obtain empirical data from multiple sources of data and...

Nonproportionally Loaded Steel Beam-Columns and Flexibly-Connected Nonsway Frames

Siva Prasad Darbhamulla
A theoretical study of the inelastic stability of nonproportionally loaded steel beam-columns and flexibly-connected frames is conducted. Specifically, solution techniques are formulated to predict the nonlinear behavior of cross sections, spatial beam-columns, and nonsway plane frames under the combined influence of imperfections, flexible connections, and nonproportional loads. A set of new inelastic slope-deflection equations for imperfect members are derived and their use illustrated through in-depth studies of flexibly-connected portal and two-bay two-story frames. These equations...

Understanding the Digital Divide As It Relates to Electronic Commerce

Franklin D. Gaillard
There exists an electronic digital divide within the United States. This digital divide concerns access to the Internet and its corresponding technologies. The U.S. government is concerned about the digital divide because it appears that certain ethnic groups and income levels are being excluded from computer technologies and the Internet. These groups include African Americans and Hispanics, who are lagging the Caucasians significantly in gaining access to the Internet. For a while the gap between...

Group II Metabolic Glutamate Receptors in the Basal Amygdala Regulate Sleep and Fear-Induced Alterations in Sleep

Enheng Dong
Glutamate is a major excitatory neurotransmitter in the brain and it has been recognized as playing an essential role in activating and maintaining arousal. Group II metabotropic glutamate (mGlu II) receptors are expressed in the amygdala, a brain structure important in the regulation of stress and anxiety as well as in the regulation of sleep and arousal. Our lab has found that the central nucleus of the amygdala (CNA) is involved in the emotional modulation...

Platelet Function and Energy Metabolism During Storage in a Well-Defined Experimental Medium

Thais Edwina Ahrendt Keegan
The most significant problem in maintaining platelet viability during storage is the decrease in pH resulting from accumulation of lactic acid formed by platelet anaerobic glycolysis. This study investigates nutrient alternatives to glucose for maintenance of morphology and functional integrity during platelet storage in a well-defined synthetic medium and correlates this data with purine nucleotide levels determined by high-performance liquid chromatography (HPLC) and other in vitro measures of platelet quality. Platelets prepared from pooled ABO-...

Development and Characterization of Monoclonal Antisperm Antibodies: Potential for Contraception

Dilrowshan H. Haque
There is an expressed need to develop a greater variety of safe contraceptive methods which would find acceptance worldwide, particularly in developing countries. Immunization against spermatozoa might be such a method as judged by the accumulated evidence from studies on human females and in a number of female animal species. Two extraction techniques were used for sperm membrane antigen isolation. The first technique involved NP-40 detergent for antigen extraction from human motile sperm and the...

Analysis of Jump Linear Systems Driven by Lumped Processes

Jorge R. Chavez Fuentes
Safety critical control systems such as flight control systems use fault-tolerant technology to minimize the effect of faults and increase the dependability of the system. In fault-tolerant systems, the system availability process indicates the current operational mode of an interconnection of digital logic devices. It is a process that results from the transformation of the stochastic processes characterizing the availability of the devices forming the system. To assess safety critical control systems, the following measures...

Multilevel Parallel Communications

Sanjay Khanna
The research reported in this thesis investigates the use of parallelism at multiple levels to realize high-speed networks that offer advantages in throughput, cost, reliability, and flexibility over alternative approaches. This research specifically considers use of parallelism at two levels: the "upper" level and the "lower" level. At the upper level, N protocol processors perform functions included in the transport and network layers. At the lower level, M channels provide data and physical layer functions....

The 2H(e, e'p)n Reaction at High Four-Momentum Transfer

Hassan F. Ibrahim
This dissertation presents the highest four-momentum transfer, Q2, quasielastic (xBj = 1) results from Experiment E01-020 which systematically explored the 2H(e, e'p)n reaction ("Electro-disintegration" of the deuteron) at three different four-momentum transfers, Q2 = 0.8, 2.1, and 3.5 GeV2 and missing momenta, pmiss = 0, 100, 200, 300, 400, and 500 GeV including separations of the longitudinal-transverse interference response function, RLT, and extraction of the longitudinal-transverse asymmetry, ALT. This systematic approach will help to understand...

Partial Radiative Recombination Cross Sections for Excited States of Hydrogen

Patricia M. Fazio
In calculating the radiative recombination cross sections for interstellar H II regions usually only the electric dipole term in the expansion of the interaction Hamiltonian is kept. However, conditions present in these regions permit recombination into highly excited states and the "effective size" of the atom is not much less than the wavelength of the emitted photon. These physical conditions do not meet the requirements for making the dipole approximation. A higher order approximation is...

High Energy Coupled Nucleon Tranpsort in One Dimension

Stanley L. Lamkin
The problem of energetic nucleon transport through extended bulk matter is considered in the context of the 'straight ahead' approximation. The applicable form of the Boltzmann transport equation is derived and solved in one dimension. The production term for secondary generation nucleons due to nuclear fragmentation includes 'coupling' of the flux to other types of nucleon projectiles. A physically motivated perturbation series approach is developed to enhance solution convergence. The Boltzmann operator is inverted and...

The Effects of Electron Radiation on the Glass Transition Temperature of a Polyetherimide

Kristen Tulloch Kern
The effects of electron radiation on a polyetherimide (PEI), Ultem*, were investigated. In particular, the changes in the glass transition temperature (Tg) with absorbed radiation dose were studied. The polymer was exposed to mono-energetic beams of 100-keV electrons and 1.0-MeV electrons for doses up to 100 megagray (MGy). Dosimetry for the exposures was based on Monte-Carlo simulations of the transfer of energy from an energetic electron to the polymer and on comparison to Nylon standards....

Theoretical Results Supporting the Use of Passive Damping as Augmentation to the Active Control of Flexible Structures

Joseph Vincent Harrell
One challenge of modern control technology is how to control a flexible structure with accuracy, speed, and economy of effort. Controlling a structure with many degrees of freedom by purely active means implies the implementation of inordinate sensors and actuators and creates the need for numerous calculations that must be done instantly. Experiments have shown that practical structures under active control alone can suffer instabilities due to modal vibrations beyond the bandwidth of the active...

Large-Amplitude Finite Element Flutter Analysis of Composite Panels in Hypersonic Flow

Carl E. Gray Jr.
A finite-element approach is presented for determining the nonlinear flutter characteristics of two-dimensional isotropic and three-dimensional composite laminated thin panels using the third-order-piston, transverse loading, aerodynamic theory. The unsteady, hypersonic, aerodynamic theory and the von Karman large deflection plate theory are used to formulate the aeroelastic problem. Nonlinear flutter analyses are performed to assess the influence of the higher-order aerodynamic theory on the structure's limit-cycle amplitude and the dynamic pressure of the flow velocity. A...

A Computational Aerodynamic Design Optimization Method Using Sensitivity Analysis

Mohamed E. Eleshaky
A new and efficient procedure for aerodynamic shape optimization is presented. The salient lineaments of this procedure are: (1) using a discrete sensitivity analysis approach to determine analytically the aerodynamic sensitivity coefficients; (2) obtaining the flowfield solution either by a computational fluid dynamics (CFD) analysis or, alternatively, by a flowfield extrapolation method which is based on a truncated Taylor's series; (3) defining the aerodynamic shape in such a way that it is not restricted to...

Registration Year

  • 2019
    853

Resource Types

  • Text
    853

Affiliations

  • Old Dominion University
    853