Physical Sciences and Mathematics Commons^™

Observations On The Hydraulic Regime Of The Ridge And Swale Topography Of The Inner Virginia Shelf, Barry W. Holliday

OES Theses and Dissertations

The Virginia inner shelf is dominated by southwest-trending sand ridges. Wavelengths are 2 to 4 km; amplitudes are up to 10 m; crests can be traced for up to 10 cm, Nearshore ridges trend southwest into the shore face and merge with it at depths as shoal as 5 m. The ridges have been examined by bathymetric mapping, grab sampling, coring, seismic profiling, SCUBA diving, and current monitoring. They are hemi-cylindrical sand bodies of recent age, resting on a pre-recent substrate. In troughs a thin, medium- to coarse-gained, pebbly lag veneers the substrate. Crests consist of a better sorted, medium- …

Phytoplankton Composition At Lake Drummond In The Dismal Swamp, Virginia, William Howard Poore Jr.

Biological Sciences Theses & Dissertations

Abstract unavailable.

A Graphic Analysis Of Current Velocity Salinity Density And Temperature During Periods Of Ebb And Flood In The Entrance To Thimble Shoals Channel, Stanley Hecker

OES Theses and Dissertations

A graphic analysis is presented of the observed patterns of longitudinal current velocity, salinity, density and temperature through a group of tidal cycles in Thimble Shoals Channel. Graphs of the properties indicate that this estuary passes through a sequence of estuarine types during a tidal cycle. In spite of this observation, the net non-tidal profiles of salinity are patterns of a partially mixed estuary.

The most noteworthy observation in this study was that longitudinal velocity was essentially constant throughout the water column at any increment of a tidal cycle as well as in the net non-tidal profile of the water …

Analysis Of Littoral Transport By Wave Energy: Cape Henry, Virginia To The Virginia, North Carolina Border, Zvi Henry Weinman

OES Theses and Dissertations

An investigation of the rate of littoral transport by an analysis of wave energy for the area from Cape Henry, Virginia to the Virginia, North Carolina border is made. Wave refraction diagrams are done by digital computer. Total upcoast (northerly) transport is determined to be 2.05 x 10⁶ yds³/year. Total downcoast (southerly) transport is determined to be 1.07 x 10⁶ yds³/year. Net transport is determined to be 9.8 x 10⁵ yds³/year in an upcoast (northerly) direction. The values obtained are compared with those of similar areas. The general efficacy of the …

Spectroscopic Measurement Of The Electron Temperature In The Tenuous Argon Ion Laser Plasma, Dane Danijel Bicanic

Physics Theses & Dissertations

The validity of the line intensity ratio technique for measuring the electron temperature was examined for an argon plasma with a "population inversion" i.e., the number of ions with electrons in the upper 4p levels was greater than in the lower 4s levels. The line intensities from these levels, the argon ion lasing transitions, were measured in a pulsed tenuous plasma at 110μ Hg produced by discharging a capacitor through a tube 2m long and 7mm inside diameter. The electron impact cross sections for simultaneous excitation and ionization as measured by Latimer and St. John were used and averaged over …

An Experimental Investigation Of The Vortex Sink Rate Sensors, Nelson L. Lu

Mechanical & Aerospace Engineering Theses & Dissertations

The vortex sink rate sensor device consists basically of an ideal sink flow between two coaxial disks. A sink tube was located at the center of one disk. The vortex was created by the rotation of the unit about its axis of symmetry. Five inch and 10 inch diameter of porous couplers were used for the air chamber here in this investigation. Several slenderness parameters, i.e., the ratio of the sink tube diameter to the height of the air chamber ^ro/n were conducted. Two probes were used to measure the static pressure and stagnation pressure respectively at various positions …

Behavioral Styles Of Computer Programmers - Revisited, Edward M. Cross

Information Technology & Decision Sciences Faculty Publications

This paper describes the second phase of a continuing research project concerned with the attributes associated with membership and success in the computer programming occupation.   The second phase of this research has differed some-what, both in intent and practice, from the first phase. First, the initial purpose of the study was to test an approach to job analysis which included the application of the principal instrument used in the study, the JAIM, or Job Analysis and Interest Measurement.1 The use of computer programmers as the subject group was the result of the investigator's previous career as a systems analyst and …

Nutrient-Density Relationships In The Western North Atlantic Between Cape Lookout And Bermuda, Unnsteinn Stefánsson, Larry P. Atkinson

CCPO Publications

A study of the nutrient-density relationships of Sargasso Sea water reveals a close correlation; Gulf Stream waters are anomalously higher and more variable in nutrients for a given density. Nutrient anomalies can be used in the same way as oxygen anomalies to map the distribution of Caribbean water in sections across the Gulf Stream. They show that contributions of Caribbean water to the Gulf Stream vary greatly from time to time. Oxidative ratios of ΔO : ΔN : ΔP = (−233) : 16.3 : 1.0 were derived from the correlation between oxygen anomalies and nutrients anomalies of Gulf Stream water …

An Evaluation Of An Electromagnetic Current Meter For Study Of Water Particle Motion, George Milton Hecker

OES Theses and Dissertations

A new sophisticated electromagnetic current meter was laboratory and field tested in a wide variety of applications, ranging from measurement of net bottom currents (primarily tidal origin) on the continental shelf, to horizontal and vertical components of wave induced orbital motion of waves with periods as small as one second.

These tests indicate that this instrument is capable of performing to at least the following specifications, subject to the comments which follow:

Speed range: Accuracy: Threshold: 0 to + 5 knots + 0.2 knots + 0.02 knots Response time: 0.25 sec. Direction: -+ 7 degrees Depth: '0 to 42 feet …

Erasure Of Sediment Surface Features By Mellita Quinquiesperforata (Leske), Walter Richard Boehmer

OES Theses and Dissertations

Erasure of sediment surface features by individuals of the species, Mellita guinguiesperforata, observed in this study suggests that all members of the sub-order, Scutellina, are able to erase sediment surface features. Sweep time, the time needed to erase the surface features of an area, depends on the population density, individual size, and speed of movement of the sand dollars. Assuming their pattern of movement as random, the following equation can be used to determine sand dollar sweep time,

T - 3.2 N^-0.76 (W / S) (A/ W² )^1.21

where T is sweep time, N is the …

Grain Size Reconnaissance Of The Virginia-North Carolina Inner Shelf Analysis By Settling Technique, Robert Bailey Sanford Jr.

OES Theses and Dissertations

The 2-fold purpose of this study is to calibrate a Rapid Sediment Analyzer and to use it to aid in the determination of the genesis of sediment on the inner continental shelf between Cape Henry and Cape Hatteras. Rapid Sediment Analyzer calibration was conducted by comparison of sieving and settling results of similar sands.

The study area was divided into sediment provinces by both a qualitative procedure (grain size and topography) and a quantitatively procedure (factor-vector analysis). Qualitative provinces are beach and surf, upper shore face, lower shore face, sea floor, and terminal shoals. The berm fines from each terminal …

A Numerical Solution To The Problem Of Rotation Near The Ground, David D. Chen

Mechanical & Aerospace Engineering Theses & Dissertations

No abstract.

An Investigation Of A Gas Measurement Technique Employing Ultraviolet Excitation, Alphonso Vincent Diaz

Physics Theses & Dissertations

A study was undertaken to determine the general applicability of a temperature measurement technique which uses the fluorescence stimulated by a vacuum ultraviolet continuum as the indicator. This study was directed toward determining the temperature of nonradiating carbon monoxide. A number of ultraviolet radiation sources which produced high intensity in the region of l,150 A were investigated. This study led to the conclusion that the technique was not applicable to measurements in carbon monoxide within the present limits of' detectability.

Excitation Of Hydrogen Atoms By Fast Protons, Edward Ellis Fitchard

Physics Theses & Dissertations

In this thesis a theoretical study is made of excitation of hydrogenic atom by charged particles such as protons or electrons. The approximation to the cross section for an inelastic scattering process is obtained under the following radically simplifying assumptions. The projectile is represented in its initial and final state by plane waves. All distortions are neglected whether they originate in an inelastic process or an elastic deflections of the charged particle by the nucleus. The perturbation of the atomic orbits between which the projectile induces transitions is neglected. Nonrelativistic hydrogenic wave functions are used for the electronic states. In …

Quaternary Sedimentation On The Inner Atlantic Shelf Between Cape Henry And Cape Hatteras: A Preliminary Report, Donald J. P. Swift, Gerald L. Shideler, Nicholas F. Avignone, Barry M. Holliday, Charles E. Dill Jr.

OES Faculty Publications

The coast of the Middle Atlantic Bight of North America's Atlantic shelf consists of a series of spit - barrier island systems attached on their northern ends to eroding headlands. It has been suggested that these barriers were generated as coastwise-prograding spits (Fisher, 1967) or alternatively as mainland beaches detached by the Holocene rise of sea level (Hoyt, 1967). The shore face before the barriers consists of fine, seaward-fining sand. Locally, it is corrugated by oblique-trending ridges with up to 8 metres of relief — see for instance CSGS Chart 1109. Beyond the shore face lies a vast submarine sand …

A Fluorescent Tracer Study At A Tidal Inlet (Rudee Inlet, Virginia), James W. Bunch

OES Theses and Dissertations

Patterns and approximate rates of littoral transport south of Rudee Inlet. Virginia were investigated with fluorescent tracers. Sand movement was traced under a variety of longshore current and wave conditions. Patterns of tracer dispersal reflected the importance of wave height, breaker angle, and longshore current velocity on modes of littoral transport. A direct relationship between angle of breaker incidence. generated longshore current. and direction of tracer sand movement was found. Onshore offshore paths were taken by tracer material during periods of weak longshore currents and small breaker angles while alongshore paths were followed by tracer material during strong longshore currents …

Population Excitation Mechanism Of The First Negative System Of Nitrogen, Robert Lynn Bridigum

Physics Theses & Dissertations

The photoionization process of nitrogen was studied using the helium resonance line (584 Å) to excite nitrogen from the ground state to an excited ionic state. The transitions from the second excited state of the ion, N+2B²Σt+u to the ground state of the ion, N+2X²Σ+g, were of particular interest. The nitrogen fluorescence was spectrally analyzed in the region from 2000 Å to 5000 Å , to determine the most prominent bands of the first negative system. Two unresolved bands were observed: the v = 0 to v =.O band at 3914 Å, and the …

The Occurrence And Distribution Of Methane In The Marine Environment, Larry P. Atkinson, Francis A. Richards

CCPO Publications

The distributions of methane dissolved in the sulfide-bearing waters of the Black Sea, the Cariaco Trench, and Lake Nitinat are reported. The gas was not detected in the oxygen-deficient water of the eastern tropical Pacific Ocean, in the Santa Barbara Basin, nor in the sulfide-bearing water of Saanich Inlet. Maximum concentrations observed were 70 μmole CH4/l., and the distribution tends to follow that of sulfide. The data indicate that methane is derived from organic compounds not containing nitrogen or phosphorus and that its formation is much slower than that of sulfide. The solubility coefficient in seawater (salinity = 40‰) is …

The Occurrence And Distribution Of Methane In The Marine Environment, Larry Philip Atkinson

OES Faculty Publications

The distribution of methane in several anoxic marine environments is described. Maximum concentrations observed were μ mole CH₄-C/liter. The distribution of methane seems to follow that of sulfide. The data indicate that methane is derived from organic compounds not containing nitrogen or phosphorus and that its formation is much slower than that of sulfide.

Diurnal Distribution Of Phytoplankton From A Single Station At The Mouth Of The James River, Harold G. Marshall

Biological Sciences Faculty Publications

Eight sets of water samples were taken to a depth of 36 ft. during a 24-hr. period. A homogeneity was found in the vertical distribution of the total phytoplankton in samples from 7 of the 8 hydro-casts. Skeletonema costatum and Asterionella japonica were the most numerous phytoplankters in every sample, with the majority of their counts each exceeding 500, 000 cells per liter.

Some Consequences Of The Decomposition Of Organic Matter In Lake Nitinat, An Anoxic Fjord, Francis A. Richards, Joel D. Cline, William W. Broenkow, Larry P. Atkinson

CCPO Publications

Observations in Lake Nitinat, an anoxic fjord on Vancouver Island, British Columbia, indicate that the large accumulations of ammonia, carbonates, phosphates, silicates, and sulfides in the deep water are the result of oxidative and fermentative decomposition of organic matter of planktonic origin, the reduction of sulfate ions, hydrolytic or other non-oxidative release (in the case of silicates), and the solution of carbonates (which also increases the alkalinity). Ammonia, sulfides, and silicates accumulate in the sulfide zone in direct proportion to each other, but some of the phosphate is probably released from the organic matter earlier than the other components, and …

The Distribution Of Phytoplankton Along A 140 Mile Transect In The Chesapeake Bay, Harold G. Marshall

Biological Sciences Faculty Publications

The composition of phytoplankton progressively changed in the surface samples taken between Norfolk, Virginia and Cambridge, Maryland. These was an inverse relationship between the numbers of phytoplankters and zooplankters in the transect samples. Vertical stratification of the plankton was studied at two 24-hr, stations at the Great Wicomlco and Patuxent Rivers. The vertical centers of zooplankton and phytoplankton populations fluctuated over the study period and evidence is given to support a grazing phenomenon. Large concentrations of nannoplankters were found in all the plankton samples taken and is attributed to the collection procedure using the Van Dorn sampler.

The Annual Distribution And Stratification Of Phytoplankton At Aurora Lake, Portage County, Ohio, Harold G. Marshall

Biological Sciences Faculty Publications

A 13-month study of a hard-water lake in northeast Ohio has provided a quantitative and qualitative record of the seasonal changes of the phytoplankton. Maximum production occurred during the summer and winter periods. The summer pulse was dominated by the cyanophyte species: Microcystis aeruginosa, Anabaena spiroides, A. circinalis, and Aphanizomenon flosaquae. The dominants of the winter pulse were the diatoms Fragilaria crotomensis and Asterionella formosa, which formed separate peaks under an ice cover in December and January, respectively. The January development extended into March with the highest concentrations for the year Being reached at approximately …

Succession In A Dune Community At Mentor Headlands, Ohio, Harold G. Marshall

Biological Sciences Faculty Publications

Continual sand deposition on the Lake Erie shore, adjacent to the mouth of the Grand River, has led to the formation of a developing sand dune community and through the years a successional pattern of plant growth. An analysis was made of the general plant composition of the area by means of four transects directed from the bare beach inland. Definite zonation of specific plant species was present throughout the community in parallel formation. Named for the dominant plant types they contained, the major stages were: dune grass, poplar, aspen, and oak.