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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- …

Effects Of Multiple Scattering And Surface Albedo On The Photochemistry Of The Troposphere, Tommy Reinhold Robert Augustsson

Mechanical & Aerospace Engineering Theses & Dissertations

A one-dimensional photochemical model of the troposphere containing the species of the nitrogen, oxygen, carbon, hydrogen, and sulfur families has been developed and used to investigate the vertical profiles and the natural (including atmospheric chemical reactions) and anthropogenic sources and sinks of these species. The species continuity equations are solved numerically applying prescribed boundary conditions. The vertical flux is simulated by use of the parameterized eddy diffusion coefficients. Heterogeneous losses (e.g. rainout, gas-to-particle chemistry, and dry deposition), are parameterized to make calculated profiles consistent with measurements. The photochemical model is coupled to a radiative transfer model that calculates the radiation …

Games And Gaming Of The Stuart Aristocracy, Vicky Ann Sanderlin

History Theses & Dissertations

Games and gaming provide insight into the lives of the people of the past. This thesis analyzes the games and gaming patterns of the aristocracy of Stuart England. This examination of gaming concentrates on the place of leisure games in the world of the elite. The study focuses on games suitable for inclement weather and includes both children's and adult's games from the period.

This thesis addresses three basic questions: 1) who were the gamesters, 2) when and where did they game, and 3) what games did they play and how did they play them? Answers to these questions have …

Characteristics Of Sediment Transport In Overwash Surges, Paul Richardson Bowen

OES Theses and Dissertations

Sediment samples taken from a washover deposit were used to determine the mode of sediment transport within overwash surges. The determination of sediment transport mode is based on the concept of hydraulic equivalency of different density grains. Hydraulic equivalency may be based on settling velocities or entrainment velocities. Two individual mineral grains of different densities cannot have the same settling and entrainment velocities. If the settling velocities of each grain are similar, then the less dense grain must be physically larger to settle at the same rate as the smaller denser mineral. However, once both of these grains have made …

Chemistry Of Organic N-Chloramines, Formation Of Arenesulfonamides By Derivatization Of Organic N-Chloramine With Sodium Arenesulfinate, Katherine F. Bowdring

Chemistry & Biochemistry Theses & Dissertations

Organic N-chloramines are recognized by-products of chlorinated water systems. Because of their chemistry, none have been isolated or identified.

This paper discusses a method for the derivatization of the organic N-chloramines based on a nucleophillic substitution mechanism. N-Chloro derivatives of amines of various structures were studied including primary and secondary aliphatic amines, as well as amino acids. The effect of the presence of other functional groups including aromatic and unsaturated systems was investigated.

Derivatization was done by three different methods, one involving derivatization of the pure N-chloramine, and two involving derivatizations of the N-chloramine generated in situ. Seventeen arenesulfonamides have …

The Synthesis And Evaluation Of The Biological Activity Of Heterocyclic Analogs Of Phencyclidine, Julian Dew Mckenney Jr.

Chemistry & Biochemistry Theses & Dissertations

Using the classical synthetic approach described by Maddox and co-workers⁴³, the decyanation reaction of 1- piperidinocyclohexane carbonitrile (PCC), 5, was attempted using the heterocyclic anions of 2-methyl-5-nitropyridine, 22, 2-amino-5-nitropyridine, 23, and 2-hydroxy-5-nitropyridine, 24; however, the desired pyridine analogs of phencyclidine (PCP), 1, could not be prepared under these conditions. Attempts to prepare the same analogs via addition of these anions to the iminium tosylate and hydrobromide salts also proved unsuccessful.

The failure to observe the desired decyanation reaction has been attributed to the special sterochemical restrictions of the hindered nitrile of PCC in that facile …

The Effect Of Kindergarten Entrance Age On School Success In Kindergarten And First Grade In Selected Portsmouth Private Schools, Mary Lindsey H. Hester

Theses and Dissertations in Early Childhood Education

This two-year study compared kindergarten children by age and sex on cognitive development, emotional adjustment, and social development. A similar comparison was made of the sample at the end of their first grade year.

The sample (N=57) consisted of the total kindergarten enrollments of two private schools in Portsmouth, Virginia. Those children who had entered kindergarten before their fifth birthday were defined as "younger," and the remaining sample, "older."

The tool for measuring cognitive development was the Metropolitan Readiness Test in kindergarten, and the Metropolitan Achievement Test in first grade. A self­ designed developmental rating sheet was used both years …

Growth And Recruitment Of Two Penaeids In The Bay Of St. Louis, Mississippi During 1979, Teresa C. Heaton

OES Theses and Dissertations

Juvenile brown (Penaeus aztecus, Ives) and white (Penaeus setiferus, Linnaeus) shrimp were collected from two stations of a nursery area in St. Louis Bay Mississippi, during May to October, 1979. Periods of shrimp recruitment and growth were determined to discern whether the concurrent environmental variables of salinity and temperature had an influence on shrimp abundance and yield. Growth estimates were obtained from length frequency measurements of trawl samples taken over a 24-h period per month from each station. An analysis of variance of length versus the variables of sex, month, station, time of day, salinity and …

Continental Shelf Processes Affecting The Oceanography Of The South Atlantic Bight. Progress Report, 1 June 1980-1 June 1981, Larry P. Atkinson

CCPO Publications

(Introduction) In the past year we executed our largest field effort to date, GABEX-1. The vast amount of data gathered has now been reduced to workable form and we report on some of the first results in this report. The GABEX-1 measurements combined with other observations in the last year have greatly increased our understanding of the South Atlantic Bight during the spring transition period when the shelf goes from horizontal to vertical stratification.

This progress report contains selected reprints, drafts, and parts of technical reports that represent our work over the past three years.

Numerical Model Simulation Of Offshore Flow During The Winter Season, Maria Cintia Piccolo

OES Theses and Dissertations

Because of the step function variability of heat and moisture flux in coastal zones, adequate descriptive models of mesoscale coastal circulation and weather patterns demand high spatial resolution in the analysis of wind, temperature and moisture patterns. To obtain realistic concepts of offshore flow the sparse offshore data networks need to be supplemented by mesoscale numerical models. The problems associated with the modeling of offshore flow across the east coast of the United States during the winter season have been investigated with a simple two dimensional numerical model of the planetary boundary layer.

The model has two predictive equations for …

The Relationship Of Student Sex, Attractiveness, And Self-Esteem To Teacher Preference Of Seventh Through Eleventh Grade Private School Students, Susan Montgomery Booker

Teaching & Learning Theses & Dissertations

This study tested the null hypotheses that student sex, attractiveness, and self-esteem were not related to teacher preference. It was assumed that these variates were communicated nonverbally through photographs. Two hundred twenty yearbook photographs of Caucasian seventh through eleventh grade students attending a private school were considered for the study. Attractiveness and self­ esteem scores were associated with each student's :10Lo­ graph. The attractiveness score was obtained by a survey of the photographs. The Coopersmith Self-Esteem Inventory was administered to the students to produce the self-esteem score. A set of criteria was established to determine degrees of attractiveness and self-esteem. …

Geomorphology And Dynamics Of A Sand Wave In Lower Chesapeake Bay, Virginia, Gerardo Miguel Eduardo Perillo

OES Theses and Dissertations

A single, more or less isolated, sand wave in a sand wave field recently discovered in the lower Chesapeake Bay, Virginia, was studied intensively for morphology, sedimentology and in terms of dynamic processes. The morphologic investigation consisted of bathymetric surveys of the sand wave field and the specific sand wave. Twenty-five grab samples and four box cores were obtained from different segments of the feature studied. Textural parameters of the samples were determined, and a multivariate technique was utilized to identify subenvironments on the feature. The box cores provided information on the internal structure of the sand wave.

Observations of …