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Femtosecond Photoemission Study Of Ultrafast Electron Dynamics On Cu(100), J. Cao, Y. Gao, R. J. D. Miller, Hani E. Elsayed-Ali, D. A. Mantell

Electrical & Computer Engineering Faculty Publications

The energy dependence of the relaxation of photoexcited electrons in copper was measured using femtosecond time-resolved photoemission spectroscopy to within 0.3 eV above the Fermi level. By performing lifetime measurements under different surface conditions, several surface dynamical processes were investigated. In particular, an anomalous long lifetime feature, which cannot be explained with Fermi-liquid theory, was observed in the lifetime-energy curve. This feature was found originating from the photoexcitation of the strongly localized Cu 3d electrons. ©1997 American Physical Society

Cualse² Thin Films Obtained By Chalcogenization, S. Marsillac, K. Benchouk, C. El Moctar, J. C. Bernède, J. Pouzet, A Khellil, M. Jamali

Electrical & Computer Engineering Faculty Publications

CuAlSe₂ thin films have been synthesized by chalcogenization of thin Cu and Al layers sequentially deposited by evaporation under vacuum. It is shown that CuAlSe₂ films are obtained with some Cu₂-_δSe and Se phases present at the surface. These surface phases are suppressed by annealing under vacuum and by chemical etching in a KCN solution. At the end of the process, the XRD spectrum demonstrates that textured CuAlSe₂ films have been obtained with preferential orientation of the crystallites along the (112) direction. The gap of the films is 2.7 eV as expected. The …

A Survey Of Architects And Engineers In The State Of Virginia To Determine If Traditional Drafting Skills Should Continue To Be Taught In Virginia's High Schools, James M. Peters

OTS Master's Level Projects & Papers

The following questions guided this research design: 1. Determine the use of traditional and computer aided drafting tools and skills in architectural and engineering firms; 2. Determine whether architects and engineers feel that it is important to continue to teach traditional drafting skills in high school technology education classes; 3. Determine whether architects and engineers feel that it is important to teach CAD skills in high school technology education classes; 4. Determine what type(s) of CAD programs are currently in use in architectural and engineering firms.

An Analysis Of The Attitudes Of Technology Education Students Enrolled In The Military Career Transition Program At Darden College Of Education, Old Dominion University, Rodney L. Pastore

OTS Master's Level Projects & Papers

Through the analysis of the reasons given by students for enrolling in Old Dominion University's MCTP and Technology Education programs, the following goals will be answered: 1. Determine the reasons why students selected the Military Career Transition Program; 2. Determine the reasons why students enrolled in the Technology Education programs; 3. Assess the motivational and attitudinal factors contributing to their enrollment and completion of the Military Career Transition Program, Technology Education program.

Microwave Plasma Chemical Vapor Deposited Diamond Tips For Scanning Tunneling Microscopy, Sacharia Albin, Jianli Zheng, John B. Cooper, Weihai Fu, Arnel C. Lavarias

Electrical & Computer Engineering Faculty Publications

Diamond microparticles were grown on etched tungsten wires using a microwave plasma-assisted chemical vapor deposition process. The apexes on cubo-octahedral particles bound by {100} and {111} facets were effectively used as tunneling tips for scanning tunneling microscopy. The atomically resolved surface image of highly oriented pyrolytic graphite was acquired. Tunneling characteristics revealed a higher electron emission from the diamond tips than that from the platinum–iridium tips. The same diamond tips were used to produce surface indentation and its image. © 1997 American Institute of Physics.

Optical And Electrical Properties Of Cualse² Thin Films Obtained By Selenization Of Cu/Al/Cu... Al/Cu Layers Sequentially Deposited, J. C. Bernède, S. Marsillac, C. El Moctar, A. Conan

Electrical & Computer Engineering Faculty Publications

Optical and electrical properties of CuAlSe₂ thin films obtained by selenization of Cu/Al/Cu...Al/Cu layers sequentially deposited have been investigated. It is shown that the expected energy gap (2.67 eV) is measured for well crystallized films, whereas a slightly higher value is measured for films not so well crystallized. Raman diffusion also shows differences between well and poorly crystallized films with peaks corresponding to the reference powder for the former samples. A p-type conductivity is found whatever the crystalline quality of the samples. The conductivity of the films depends also strongly on their crystalline properties. When the films are badly …

The Effect Of Safety Training At The Ford Assembly Plant In Norfolk, Virginia, Maggie Daniels

OTS Master's Level Projects & Papers

These research goals were established to answer the problem and provide guidelines to conduct the research: 1. Determine when, how often, and under what conditions safety training was given; 3. Determine what teaching method was used in the delivery of safety training; 3. Determine the amount of lost time due to safety violations before and after the safety training was given.

A Follow-Up Study Of Technology Education Graduates Of Old Dominion University 1986-1996, Mark D. Siciliano

OTS Master's Level Projects & Papers

Through the follow-up study, data was collected toward fulfilling the following objectives: 1) to determine if graduates of Old Dominion University's Technology Education Undergraduate Program were adequately prepared to assume teaching positions; 2) to determine whether the goals established in the college's conceptual framework were being attained; 3) to determine if these graduates are teaching traditional vocational programs or technology education; 4) to determine what improvements can be made to the undergraduate curriculum at Old Dominion University based upon graduate's feedback.

Turbulence Modeling Of The Toroidal Wall Heat Load Due To Shear Flows Over Cavities In The Neutral Gas Blanket Divertor Regime, George Vahala, Linda L. Vahala, Joseph Morrison

Electrical & Computer Engineering Faculty Publications

Heat loads to the target plate in reactor tokamaks are estimated to be orders of magnitude higher than those that can be withstood by known materials. In regimes of plasma detachment, there is strong evidence that plasma recombination occurs near the divertor plate, leading to a cold neutral gas blanket. Because of the strong coupling between the plasma and the neutrals within the divertor region, there is significant neutral flows along field lines up to Mach 1.2 and Reynolds numbers over 1000. The effects of three dimensional (3D) neutral turbulence within the gas blanket on heat deposition to the toroidal …

Analysis Of Repeated Measures Data Under Circular Covariance, Andrew Montgomery Hartley

Mathematics & Statistics Theses & Dissertations

Circular covariance is important in modelling phenomena in epidemiological, communications and numerous physical contexts. We introduce and develop a variety of methods which make it a more versatile tool. First, we present two classes of estimators for use in the presence of missing observations. Using simulations, we show that the mean squared errors of the estimators of one of these classes are smaller than those of the Maximum Likelihood (ML) estimators under certain conditions. Next, we propose and discuss a parsimonious, autoregressive type of circular covariance structure which involves only two parameters. We specify ML and other types of estimators …

Diamond For Fiber-Optic Raman Spectroscopy, Jianli Zheng

Electrical & Computer Engineering Theses & Dissertations

Raman spectroscopy is a powerful technique for molecular structural studies and concentration measurement. Being a single beam technique, the Raman intensity depends on the optical power of the excitation source, optical alignment of the system, detector response as well as species concentration. To eliminate the unwanted variations in the system and get the concentration information of the species, intensity referencing is necessary. The existing referencing methods either use a constant Raman band of the sample, or add a chemically inert material with known concentration into the sample. Unfortunately, the former method is not always applicable and the latter is not …

Characterization Of Iron Oxides And Atmospheric Corrosion Of Steel, Sei Jin Oh

Physics Theses & Dissertations

The study of corrosion behavior was performed using three different analytical techniques, which provided information on the formation, development and layering of iron oxides on the corrosion products as a function of atmospheric conditions, exposure time and type of steel. In particular, the protective layer formed on weathering steel was investigated as a function of different amounts of alloying elements in the steel, atmospheric conditions and exposure times. Combined together, the results provided a better understanding of the atmospheric corrosion behavior of steel, and formed a part of database of the atmospheric corrosion characteristics.

Accurate characterization of the iron oxides …

An Investigation On The Effect Of Aging And Fatigue Damage On The Mechanical Properties Of A Graphite/Bismaleimide Composite, William M. Johnston Jr.

Mechanical & Aerospace Engineering Theses & Dissertations

This investigation utilizes the open hole tension (OHT) specimen loaded in tension-tension fatigue under isothermal, fixed frequency conditions. A range of load levels and temperature levels where chosen to assess performance. These loads and temperatures ranged from relatively benign conditions (low stress, room temperature) up through aggressive conditions (high stress, high temperature). Measurements of stiffness, damage accumulation, residual strength, weight loss, and glass transition temperature (Tg) were made. Results from this work will help explain the roles of aging, load and fatigue in the performance of elevated temperature OHT specimens as well as provide insights to the individual and synergistic …

A Study To Determine The Differences In Undergraduate Technology Education Teacher Preparation Curricula In Virginia, Cecil Stanley Burgett

OTS Master's Level Projects & Papers

These goals were analyzed to detect the specific variances among the four technology education certification programs in Virginia: 1. How are the Virginia technology education teacher preparation programs accredited? 2. What is the pedagogical curriculum in undergraduate technology education teacher preparation at each university? 3. What is the technical content of the four Virginia undergraduate technology education teacher preparation programs? 4. What are the field experiences of the four Virginia undergraduate technology education teacher preparation programs? 5. What are the general education requirements of each program?

A Study On The Feasibility Of Implementing Advanced Placement Courses In The Field Of Technology Education, Donald S. Luebbecke, Mark A. Mcgrath

OTS Master's Level Projects & Papers

This study was developed with three goals in mind: 1. To determine the opinions of state supervisors/directors of Technology Education concerning the establishment of an AP program for Technology Education; 2. To request recommendations or nominations for AP credit content areas applicable to Technology Education from state supervisors/directors; 3. To determine the procedures to be followed by the Technology Education profession and The College Board to establish and implement a Technology Education AP program.

A Study To Determine The Demographics And Personal Reasons Students Choose To Take, Robin Marsh Simmons

OTS Master's Level Projects & Papers

The following goals were established to guide the research: 1) Assess the demographics of students choosing to take computer mediated course; 2) Determine the personal reasons students choose virtual classrooms over traditional classrooms.

The Crash Simulation And Analysis Of The Friendly Mobile Barrier, Bryan Edward Marz

Mechanical & Aerospace Engineering Theses & Dissertations

Mass transportation is an ever increasing alternative being researched and evaluated in today's society. With the increase of demand for such transportation, an increase in safety is also needed. This research entails the analysis of a new idea, The Friendly Mobile Barrier, in railroad crossing barrier design. The design is meant to prevent any approaching vehicle from crossing a railroad track and be survivable for those impacting the barrier.

Research conducted involves the crash simulation and analysis of the Friendly Mobile Barrier. The Friendly Mobile Barrier was analyzed structurally using finite element analysis. An advanced lumped-mass mathematical model software, Crash …

Effects Of Initial Geometric Imperfections On The Behavior Of Graphite-Epoxy Cylinders Loaded In Compression, William Allen Waters Jr.

Mechanical & Aerospace Engineering Theses & Dissertations

The results of an experimental and analytical study of selected composite cylinders loaded in axial compression beyond buckling are presented. A comparison is made of buckling loads predicted by a nonlinear finite element code and those obtained from laboratory experiments. The initial geometric imperfections for each specimen were defined mathematically for inclusion in the finite element model. The experimental effort consisted of testing five graphite-epoxy cylindrical specimens. Four of the specimens were 16 plies thick; one of these had quasi-isotropic wall properties, another consisted entirely of angle plies, while the remaining specimens of this wall thickness were of two different …

Characterization Of Rainfall Runoff Quality From A Shipyard Drydock, Peter Pommerenk

Civil & Environmental Engineering Theses & Dissertations

Water quality and hydrological data were collected during seventeen rain events and additional data was obtained from laboratory experiments to characterize the quality of stormwater runoff from a drydock located on the Elizabeth River in Norfolk, Virginia.

The results indicated that the concentrations of dissolved constituents in drydock runoff increased with decreasing flow rate, while solids concentrations exhibited positive correlation to flow rate, suggesting that the mobilization of particulate matter is velocity driven. Approximating the runoff hydrograph due to a storm event using a simple model enabled derivation of the average time that rainwater resides on the drydock surface before …

The Effectiveness Of Film Cooling In A Hypersonic Flowfield With Favorable Pressure Gradients, Julie A. Young

Mechanical & Aerospace Engineering Theses & Dissertations

The impetus of this technical document is to report results of aerothermodynamic cooling of a scramjet nozzle under favorable pressure gradients. The goals of film cooling are to protect the nozzle skin from the high enthalpy combustor flow, reduce regenerative cooling requirements, and decrease nozzle skin friction. A hypersonic nozzle configuration for which experimental data exists was selected as the basis of this numerical study. As a first step, the numerical results of film cooling along a flat plate are compared to previous literature to validate the numerical model. Subsequently, computations are performed to study the effects of varying the …

An Experimental Study Of An Advanced Polymeric Material For Use In Total Knee Replacements Including Gait Analysis Of Mobile Knee Bearings, Lisa Ann Scott

Mechanical & Aerospace Engineering Theses & Dissertations

The primary objectives of this research were to clinically examine the New Jersey Low Contact Stress (LCS)™ Rotating Platform and Meniscal knee bearing systems and to investigate the tribological properties of a new polymer for potential application in total joint replacement. Thus, clinical studies were performed on subjects having the LCSTM Rotating Platform knee bearing and subjects having the LCS™ meniscal knee bearing. The results indicated that there was a statistically significant difference in the braking force for both implant groups when compared to a control group. There was also a statistically significant difference noted for the LCS™ Rotating Platform …

Real-Time Visual Speech Articulation Training Aid, Neiyer S. Correal

Electrical & Computer Engineering Theses & Dissertations

A real-time visual articulation training aid has been implemented. It provides instantaneous visual feedback of vowel and stop-consonant production on a computer screen. The vowel training system corresponds to an improved floating-point implementation of a previous fixed-point system developed by Beck (1992). The new implementation provides better accuracy and an approximate five-fold increase in speed. Acoustic features computed from global short-time spectral shape are used for classification of vowels. Temporal spectral trajectories timed to begin with burst onset are used for stop consonants. A neural network is used to transform measurements of auditory stimuli from the feature space to a …

Circulation, Fall 1996, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 1996 issue of CCPO Circulation featuring article "Antarctic Continental Shelves Are Strange And Unique"

Monte Carlo Simulations Of Photoemission Characteristics From Gaas And Diamond, Abhishek Srivastava

Electrical & Computer Engineering Theses & Dissertations

Monte Carlo based numerical simulations were performed to study photoemission from GaAs and diamond. The central goal was to assess the potential for NEA photoemission from diamond, and to predict its characteristics. The GaAs material system was also included in the simulation study to provide: (i) calibration and validation of the numerical model developed by carefully matching the simulation results with available experimental data, and (ii) quantitative comparisons between the response characteristics of diamond and the better known GaAs system.

Predictions of the energy distribution, temporal response and angular distribution of emitted electrons were obtained. Effects of various parameters, such …

Parental Quality Ratings Of Early Child Care Experiences And Subsequent School Adjustment, Donna Owens Collier

Psychology Theses & Dissertations

The purpose of the present study was to investigate differences in the school performances of children with different early child care experiences. The relationship between parental quality ratings of early child care experiences and subsequent school performance was also examined. The subjects in this study were 99 first grade students from two public elementary schools in Chesapeake, Virginia. The parents of these students were asked to assess broad areas of their children's early care. This assessment resulted in four subscores and one overall score of quality. The school performance scores included two measures of academic achievement obtained from the students' …

Development And Experimental Verification Of A Finite Element Model For Ptc Panel Thermal Analysis, Hamid Sayar

Mechanical & Aerospace Engineering Theses & Dissertations

The Pyramidal Truss Core (PTC) panel is a new structural concept being used in applications requiring a high strength to weight ratio. This study is concerned with investigating the thermal characteristics of the PTC panels. In this regard, the focus of the analysis was to develop an accurate finite element model of PTC panels for thermal analysis. The resulting model included radiation mode of heat transfer as the dominant means of the heat transfer while neglecting the influence of heat transfer through natural convection. The accuracy of the developed model was verified by comparison of the finite element results with …

Dynamics And Control Of A Three Dimensional Gantry Crane With Cable Flexibility, Uchendu H. Eke

Mechanical & Aerospace Engineering Theses & Dissertations

The control of payload swing in industrial gantry cranes is a topic of widespread interest. In this thesis, the control of the swing of a payload idealized by a point mass assumption is investigated utilizing s, compact robotics matrix/vector representation of the dynamical model. In this form, this particular system can be viewed as sn underactuated manipulator with equal numbers of active and passive degrees of freedom. The full three dimensional model is developed and linearized by modelling the cable as a single thread of fiexible wire and the degree of dynamic coupling between the active and passive coordinates is …

Josiah Gorgas And The Richmond Ordnance Industry: The Arsenal Of The Confederacy, J. Michael Moore

History Theses & Dissertations

This study determines that Richmond, Virginia was the center of the Confederate domestic ordnance industry, and Josiah Gorgas, the Confederate Chief of Ordnance mobilized the city's industrial potential. Richmond's government ordnance facilities and private companies manufactured artillery, shoulder arms, ammunition, tools, and other ordnance materials that prolonged the war. In addition, Richmond became the center for Confederate ordnance research. Despite serious logistical problems, Gorgas supplied the Confederate Army's demand for arms and ammunition until 1865. Finally, Gorgas's mobilization of Confederate industry remains instructive for any nation going to war. These conclusions are based on extensive research of the National Archives …

Parametric Correlations For Generic Scramjet Combustors With Ramp-Type Injectors, Jason Granville Bush

Mechanical & Aerospace Engineering Theses & Dissertations

Development of an efficient scramjet combustor requires the use of computational models due to the cost of full-scale physical testing in the speed regime of Mach 10 through Mach 18. This study focuses upon the database generated by one such computational model, SHIP3D, which describes a generic scramjet combustor using ramp-type file! injectors. Three generalized parametric equations have been developed from this database, which describe the fuel-air mixing efficiency within the scramjet combustor as a function of normalized-axial combustor distance, ramp injector-region lift coefficient, and stoichiometry. It is shown that one of the three equations nearly models the trends as …

Construct Validation Of The Small Unit Equal Opportunity Climate Survey, Arlene L. Pace

Psychology Theses & Dissertations

The purpose of the present study was to continue in the development of an equal opportunity climate survey, suitable for small groups, by establishing the construct validity of this newly developed measure. Four-hundred and twenty-nine members of 7 United States Coast Guard Units were administered the Small Unit Equal Opportunity Climate Survey (SUEOCS), an attitudinal instrument suitable for small groups. Conceptual analyses, item and scale analyses, and a confirmatory factor analysis via LISREL VIlI (Joreskog & Sorbom, 1989), were used to establish the factor structure of the SUEOCS. The results of these analyses indicated that the hypothesized factor structure was …