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A Study To Determine The Major Reasons For The Mass Exit Of Industrial Arts Teachers In The Chesapeake Public School System, Richard L. Macdonald

OTS Master's Level Projects & Papers

This study sought to answer the question of why so many vocational education teachers in the Chesapeake school district were seeking other careers.

Picosecond Laser Pulse Irradiation Of Crystalline Silicon, K. L. Merkle, H. Baumgart, R.H. Uebbing, F. Phillipp

Electrical & Computer Engineering Faculty Publications

Morphology changes introduced by picosecond laser pulses at λ = 532 nm and 355 nm in (111) and (100) silicon samples are studied by means of optical and high-voltage electron microscopy. Depending on energy fluence, orientation and wavelength, amorphous or highly defective regions may be created. From an analysis of damage thresholds and damage depth distributions it is concluded that melting and energy confinement precedes the formation of the structural changes.

Electrical And Structural Properties Of P-N Junctions In Cw Laser Annealed Silicon, M. Maier, D. Bimberg, G. Fernholz, H. Baumgart, F. Phillipp

Electrical & Computer Engineering Faculty Publications

Depth profiles of the electrical quality of ion implanted and cw laser annealed p-n junctions in silicon are obtained for the first time by secondary ion mass spectroscopy. A comparison with the crystallographic properties of the surface and the junction as observed by Nomarski optical microscopy as well as cross-sectional and plan view transmission electron microscopy is made. Samples containing slip dislocations show better insulation and a lower reverse bias current across the p-n junction as compared to samples with a perfect surface in agreement with current-voltage characteristics. Small dislocation loops located at the junction are found to degrade the …

Seeded Oscillatory Growth Of Si Over Sio² By Cw Laser Irradiation, G.K. Celler, L. E. Trimble, K.K. Ng, H.J. Leamy, H. Baumgart

Electrical & Computer Engineering Faculty Publications

Extensive seeded epitaxial growth of crystalline Si over SiO₂ was achieved by an oscillatory regrowth method applied to rectangular Si pads recessed into a thick SiO₂ film. Narrow (≃5 μm) via holes linked the pads with the bulk (100) Si substrate. Oriented single crystals propagated as far as 500 μm from the seeding area, following the long term advance of a scanned focused laser beam.

A Quantitative Description Of Migratory Behavior Of The Brown Shrimp (Penaeus Aztecus) With Applications In Fisheries Management, Anne Madolyn Babcock

OES Theses and Dissertations

A quantitative description of the migratory behavior of the brown shrimp, Penaeus aztecus, was established using the density approach. A theoretical time density was estimated by the proportion of catch and catch per boat hour NOAA-NMFS fisheries statistics collected in Pamlico Sound, the Neuse River, and Core Sound. A clear quantitative description of brown shrimp migratory timing is found in the time densities. The impact of various physical tactors on the progress of the fishery in time and space can be objectively evaluated by using the time density statistics as dependent variables in modeling efforts. The distributions also enable …

"The Tide Of The Unconscious" Jung, Bosch And The Archetypes Of The Garden Of Earthly Delights, Andrea R. Peck

Institute for the Humanities Theses

Many scholars have discussed the meaning of Hieronymous Bosch's The Garden of Earthly Delights concluding that Bosch's works were of a conscious nature relating to the real world. By contrast, this study, using the theories of Carl Jung, fragments Bosch's work and sees the milieu of his art through the eyes of the collective unconscious. Accordingly, a number of explanations of Jungian ideas are presented with the view to better understanding Bosch: Jung's theory of the archetypes, his view of Christianity, his analysis of medieval alchemy, as well as matrix archetypes and symbolic forms relating to The Garden. Through this …

Experimental Investigation Of A Rectangular Surface Thermal Plume, Li-Cheng Chu

Mechanical & Aerospace Engineering Theses & Dissertations

An experimental investigation of the three dimensional mean temperature distribution of a rectangular buoyant surface thermal plume has been conducted for a range of buoyancies, velocity ratios, Reynolds numbers, and for various turbulence generating screens in the crossflow. This study has been motivated by a concern about the applicability of laboratory model data for predicting prototype plume behavior.

A large scale model has been built to study a buoyant, rectangular surface thermal plume which enters at right angles to a constant temperature uniform crossflow of depth equal to that of the plume. A large water tank and flume with weir …

Analysis Of Aerothermodynamic Environment Of A Titan Aerocapture Vehicle, Hsing Chow

Mechanical & Aerospace Engineering Theses & Dissertations

The extent of convective and rad1ative heating for a Titan entry vehicle is invest1gated. The flow in the shock layer is assumed to be axisymmtric, steady, viscous, and compressible. It is further assumed that the gas is in chemical and local thermodynamic equilibrium and tangent slab approximation is used for the rad1ative transport. The effect of slip boundary conditions on the body surface and at the shock wave are included in the analysis of high altitude entry conditions. The implicit finite difference technique is used to .solve the viscous shock layer equations for a 45-degree sphere cone at zero angle …

The Effects Of Copper On Skeletonema Costatum (Greville) Cleve, Susanne Sybille Jackman

Biological Sciences Theses & Dissertations

Copper levels and dominant phytoplankton species composition were examined from six sites in Kings Creek on Virginia's Eastern Shore from March to August 1980. Creek copper levels were determined by an APDCMIBK extraction procedure and ranged from 0.003 to 0.020 mg/1. Diatoms were the dominant phytoplankters with Skeletonema costatum (Greville) Cleve emerging as a major late summer species.

Subsequent laboratory studies involved 96-hour experiments using Skeletonema costatum (clone Skel) grown in enriched natural seawater. The water was collected from Kings Creek and enriched to Guillard and Ryther's (1962) f/2 media levels. Cupric sulfate was added to the experimental culture media …

Synthesis Of Dihydroisoquinolines And Tetrahydroisoquinolines, John J. Schlager

Chemistry & Biochemistry Theses & Dissertations

Dihydroisoquinolines and tetrahydroisoquinolines are compounds which possess a variety of pharmacological activities. New easier methods of synthetic manipulations of these structures is of constant interest in the pharmaceutical industry.

This paper describes a new three step method of preparing 1-alkyl- and 1-aryl-tetrahydroisoquinolines from a tetrahydroisoquinoline. The synthesis involves the N-chlorination of tetrahydroisoquinoline followed by dehydrohalogenation with potassium superoxide. The reaction products are the dihydroisoquinolines. Overall yields range from 85-96%. The unsubstituted, 1-methyl-, and 1-phenyl-J,4-dihydroisoquinolines have been formed. Organometallation of the unsubstituted dihydroisoquinoline provides the 1-substituted tetrahydroisoquinoline. The 1-benzyl-, 1-n-butyl-, 1-ethyl-, 1-methyl-, and 1-phenyl-1,2,J,4-tetrahydroisoquinolines were prepared. The use of Grignard and …

A Direct Formulation And Computer-Implementation Of A Symbolic Network Analysis Algorithm, Timothy James Knerr

Electrical & Computer Engineering Theses & Dissertations

An algorithm for the symbolic analysis of linear, time-invariant, active or passive networks is presented. The algorithm incorporates the best features of earlier numerical and topological methods of symbolic analysis. A hybrid set of equations is formulated for a closed linear graph and arranged in matrix form. A numerical evalu­ation procedure for the determinant of this hybrid matrix results in an efficient method of symbolic analysis. A proof of the algorithm based on determinant evaluation by a permutation product expansion provides insight into relationships with other methods of symbolic analysis. A computer program implementation of the algorithm is described and …

Water Wave Refraction With Non-Linear Theory, Im Sang Oh

OES Theses and Dissertations

Two different kinds of wave refraction models are formulated in the present study using Stokes' third order wave theory. One type of model is utilized in a parametric study employing several different topographies. Wave trajectories obtained from this model, when obtained by using first and third order wave theory with and without the consideration of energy dissipation, show considerable differences. These differences are examined in more detail for a bottom of constant slope: (1) An approximate 10% difference occurs between the refraction coefficients obtained using the first and the third order wave theory. (2) Considerably different ray trajectories are detected …

Design And Analysis Of A Hybrid Thermoelectric Solar Collector, Kay Eddie Shaheen

Mechanical & Aerospace Engineering Theses & Dissertations

A conventional flat-plate collector is modified by imbedding thermoelectric power generators between the absorber plate and flow tubes in parallel finned-tube passes. As solar energy cascades through these generators a temperature differential between the hot and cold junctions of the device produces direct current electricity. Energy not converted to electric power is converted away for use in domestic space and/or water heating.

A parametric study is performed on the steady-state model via computer program in order to find values of design variables that maximize electric power production for purposes of driving pumps, fans, and ·controlling devices. The results of this …

Algal Dynamics In A Cypress Stand In The Seasonally Flooded Great Dismal Swamp, Joseph A. Atchue Iii

Biological Sciences Theses & Dissertations

The dynamics of epiphytic algae and phytoplankton were studied at a cypress stand in the Great Dismal Swamp, Virginia. Mean epiphytic algal biomass was 19.9 g m^-2 and mean planktonic biomass was 3.4 g m^-2.Nutrient concentrations in the epiphytic algae and the litter were determined. The algae had mean concentrations of 1.67% and 0.18%. They were found to immobilize as much as 0.5 g N m^-2 and 0.06 g P m^-2. This suggests that the algae are important as nutrient conservers. The phytoplankton were composed primarily of Bacillariophyceae. They exhibited a more or less …

Photoelastic Investigation Of Load Transfer In Eccentrically Loaded Single Lap Joints, Stephen Antrim Hann

Mechanical & Aerospace Engineering Theses & Dissertations

Photoelastic models of three eccentrically loaded single lap joints were analyzed. The adherends of each joint were identical and the bondlines differed in thickness and material properties. The adherends were analyzed for both cylindrical plate behavior and geometrical nonlinearity and the load transfer efficiency was examined. For all three models it was found that over 98% of the shank behaves as a cylindrical plate and that a geometrically nonlinear analysis yields bending stresses substantially lower than a linear analysis and that a relatively thick, low modulus bondline can increase load transfer efficiency.

The Use Of Microscopic Vegetative Characteristics And Leaf Characteristics And Leaf Deterioration Rates In The Formulation Of Keys Of Some Wetland Plants, Bruce Foy Williams

Biological Sciences Theses & Dissertations

Leaves of Spartina alterniflora, Spartina patens, Spartina cynosuroides, Distichlis spicata, Phragmites communis, Juncus roemerianus, Scirpus robustus, Typha latifolia, Iva frutescens, and Baccharis halimifolia were examined microscopically. Characteristics of each species were then used to develop identification keys. In addition, leaf fragments were buried in the marsh substrate to simulate a dredging and/or filling operation. At weekly intervals during each season of the year, a leaf fragment of each species was processed and examined to see if it could be identified.

Petroleum-Utilizing Bacteria: The Biological Line Defense Against Oil Pollution, Steven W. Sokolowski

Biological Sciences Theses & Dissertations

A silica gel-petroleum (SGP) medium was developed which is reliable, approximately the same cost as that of the corresponding agar-based petroleum medium, and can be made sufficiently firm to use in streaking or the spread-plate technique. Advantages of the medium include: the incorporation of all of the major ions of seawater in accordance with Dittmar's Law (the salinity of which can easily be varied from 0 to 35 parts per thousand); a wide workable pH range (5.5 to 11.6); negligable pH drift(~ 0.2 pH units after 166 days); the elimination of all but negligable amounts of syneresis, the ability to …

Breeding Birds Of Two Atlantic White Cedar Stands In The Great Dismal Swamp, Karen Terwilliger

Biological Sciences Theses & Dissertations

Breeding birds were censused during two years in two Atlantic white cedar stands of the Great Dismal Swamp, and a comparison was made with census results of the predominant swamp community, maple-gum. The maple-gum site had a higher bird species diversity than either cedar site but supported only half the density. The century-old cedar site had the highest species richness while the younger cedar site had the highest density.

Cluster analysis placed the avifauna into distinct groups which closely corresponded to the vegetative strata of the stands. Species were ordered along the height gradient using principal coordinate and detrended correspondence …

The Seasonality Of Occurrence Of Larval And Juvenile Sciaenids In A Virginia Seaside Estuary, James Howard Cowan Jr.

Biological Sciences Theses & Dissertations

The seasonality of occurrence and relative abundance of larval and juvenile fishes, particularly members of the family Sciaenidae, from a Virginia seaside estuary were determined from ichthyoplankton and trawl collections made from March 1979 to March 1980.

The larvae of 20 species distributed among 15 families were identified from the ichthyoplankton. Larvae of the bay anchovy, Anchoa mitchilli, and the Atlantic silverside, Menidia menidia, dominated the samples and made up 57 and 34%, respectively, of all larvae collected. Peak occurrence began in May and continued through August. Fish larvae were present in the study area all year.

Twenty-eight …

Jewish-Non-Military Resistance During The Holocaust, Debra J. Simmonds

History Theses & Dissertations

The purpose of this study is to examine the issue of Jewish "passive " resistance during the Holocaust. Its main objective is to determine if in fact the majority of the Jews did "passively" resist the Nazis, and whether or not this was resistance.

Based on past Jewish responses during waves of persecution, specific Jewish responses during the Holocaust, and previous definitions of resistance, one can arrive at a definition describing this type of resistance. This definition shows that Jews did resist the Nazis with acts of non-military resistance. However, due to a lack of supportive evidence, one cannot assess …

Effects Of The Dental Hygiene Curriculum On Student Creativity, Linda Kathryn Martin

Dental Hygiene Theses & Dissertations

This investigation examined the influence of the dental hygiene curriculum on student creativity throughout the two years of dental hygiene study. A secondary purpose was to determine if various accredited dental hygiene programs differentially affect creativity in students. Torrance Tests of Creative Thinking was used to measure creativity in students from three dental hygiene programs in Virginia. Data were organized according to a 3 X 4 factorial research design, using dental hygiene programs and academic semester levels as attribute independent variables. Fluency, Flexibility, Originality and Total scores of the Torrance Tests of Creative Thinking were the dependent variables.

Two-way analysis …

Mining The Deep Seabed Implications For International Law And American Foreign Policy, Steven H. Fitzgerald

Graduate Program in International Studies Theses & Dissertations

Whether or not the United States may someday face a mineral shortage, the need for a coherent, unified minerals policy is critical to national objectives and national security. Deep-sea mining may be the answer to American (and world) mineral needs in the twenty-first century. However, there are numerous problems which must be dealt with and resolved in the near future, in order to enable the U.S. (and the world community) to take advantage of vast undersea resources. Deep-sea mining requires the development of technology, tremendous capital investments, and years of labor before production can begin. U.S. policy makers must decide …

A Technique For The Isolation And Identification Of Aliphatic Amines In Water, Peter Alan Drew

Chemistry & Biochemistry Theses & Dissertations

Small, aliphatic amines added to a basic, aqueous solution (16.2 L) at a concentration of 100 parts per billion were isolated by sorption on a small column of macroreticular resin. The amines were eluted with diethyl ether; the eluate concentrated, and the compounds separated and identified by gas chromatography. The efficiency of the recovery of a-nines ranged from 5 to 28%.

A protocol for derivatizing pyrrolidine and n-pentylamine in ether with fluorinated acylating agents was developed. The method was found to be adequate for the detection of approximately 13 micrograms of &-nines in concentrated ether extract.

Environmental water samples …

Goertler Instability In Compressible Boundary Layers Along Curved Surfaces With Suction And Cooling, Alok K. Verma

Mechanical & Aerospace Engineering Theses & Dissertations

The Goertler instability of the laminar compressible boundary layer flows along concave surfaces is investigated. The linearized disturbance equations for the three-dimensional, counter-rotating streamwise vortices in two dimensional boundary layers are presented in an orthogonal curvilinear coordinates. The basic approximation of the disturbance equations, that includes the effect of the growth of the boundary layer, is considered and solved numerically. The effect of compressibility on critical stability limits, growth rates, and amplitude ratios of the vortices is evaluated for a range of Mach numbers for Oto 5. The effect of wall cooling and suction of the boundary layer on the …

A Method Of Modeling Multirate Two-Dimensional Recursive Digital Filters Author, Albert P. Gerheim

Electrical & Computer Engineering Theses & Dissertations

This dissertation presents a method of modeling two dimensional sampled data systems with two sampling rates in each dimension. This methodology is applied to the problem of synthesizing two dimensional velocity filters using one dimensional prototypes and multirate concepts.

The modeling method includes the replacement of scalar z-transforms of signals by vectors of polynomials, and the replacement of scalar z-transforms of impulse responses by matrices of polynomials.

The synthesis of velocity filters is accomplished through the use of coordinate transformations in the z-transform domain which skew the ω₁ -ω₂ axes on the unit bidisc. The filters synthesized using …

High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan

Chemistry & Biochemistry Theses & Dissertations

The objectives of this research were to develop a sensitive method for separation and quantitation of biogenic amines and to apply that procedure by monitoring neurochemical changes resulting from stimuli to the test system.

Primary aromatic amines were derivatized with o-phthalaldehyde-mercaptoethanol prior to chromatography, Separation of the fluorescent adduct was achieved using a μBondapak/ phenyl reversed-phase column and a two-step gradient of methanol:0.08 M acetic acid, pH J.O. Fluorescence was monitored using a J40 nm excitation energy and an emission filter which transmits radiation greater than 400 nm (50% T at 418 nanometers).

Following optimization of the chromatographic conditions, studies …

Low Speed Handling Characteristics Of A Supersonic Transport By Eigenstructure Assignment, Michael Peter Lazar

Mechanical & Aerospace Engineering Theses & Dissertations

A synthesis procedure, based upon optimal regulator theory and eigenvalue/eigenvector assignment technique, was used in the design of a low-speed lateral control system for the SCAT-15F supersonic transport. Emphasis was placed on reducing the lateral acceleration at the pilot's station. Control laws were designed to make the aircraft handling characteristics acceptable with the exception of the lateral acceleration. It was found that a compromise between the roll performance requirements and the peak lateral acceleration requirement is needed for a successful SCAT-15F design.

The Effect Of A Movement Education Program On Self Concept Among First Grade Children, Rosemarie Zumbo Tyree

Human Movement Studies & Special Education Theses & Dissertations

No abstract.

The Relationship Of Cognitive Complexity-Simplicity To Occupational Role Perception, Raymond Boetcher

Psychology Theses & Dissertations

The present research investigates the relationship of cognitive complexity-simplicity to consensus in occupational role perception between subordinate and. supervisor. The research literature indicates that role consensus for specified positions is seldom found, and. that such disparities are well-documented for various educational roles. A sample of elementary school teachers and their immediate supervisors from three southeastern Virginia school systems were administered the Role Dimension Profile Scale in order to measure the importance of various behavioral role statements. Average ratings per role dimension were computed and difference scores were obtained. for each individual teacher and his or her supervisor. Teachers were divided …

The Evolution Of The Fleet Submarine In The United States Navy, Robert P. Kendall

History Theses & Dissertations

This thesis examines the evolution of the United States Navy fleet submarine from the T-class of 1916 through the Tench-class of 1943. The fleet submarine played a major role in the defeat of Japan in World War II by attacking enemy lines of communication and supply, vital to an island empire. The author reviews the trials and errors of submarine construction in the United States Navy. Each succeeding class of submarines is discussed in order to show the progress made, leading to the excellent weapon provided for submarine officers and men with which they destroyed Japanese merchantmen and warships. Japanese- …