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Full-Text Articles in Physical Sciences and Mathematics

Comparison Of Uptake And Disposition Of Organic Pollutants In Intermolt And Ecdysial Blue Crabs, Callinectes Sapidus, Judy Lynne Haner Jan 1993

Comparison Of Uptake And Disposition Of Organic Pollutants In Intermolt And Ecdysial Blue Crabs, Callinectes Sapidus, Judy Lynne Haner

Dissertations, Theses, and Masters Projects

No abstract provided.


Market Interactions And Competition Between Public And Private Oyster Production And Supplies From Other States, Ya-Ke Hsu Jan 1993

Market Interactions And Competition Between Public And Private Oyster Production And Supplies From Other States, Ya-Ke Hsu

Dissertations, Theses, and Masters Projects

Oyster production in Virginia has declined dramatically in the past ten years, causing Virginia oyster processors to rely increasingly on oyster supplies from other regions. In response to the industry problems, the Virginia Marine Resources Commission (VMRC) developed and began implementing an Oyster Fishery Management Plan (OFMP) in 1985. Primarily, the plan seeks to increase Virginia oyster production from both public and leased grounds. A large increase in production could significantly affect the oyster market. There is thus a need to understand the Virginia oyster market, which derives raw material supplies primarily from public and leased-grounds production and from other …


A Model Study Of Hydrodynamic And Water Quality Characteristics Of The Rappahannock Estuary, Virginia, Kyeong Park Jan 1993

A Model Study Of Hydrodynamic And Water Quality Characteristics Of The Rappahannock Estuary, Virginia, Kyeong Park

Dissertations, Theses, and Masters Projects

A laterally integrated, two-dimensional, real-time model, consisting of linked hydrodynamic and water quality models, is developed and applied to the Rappahannock Estuary, Virginia. The hydrodynamic model, based on the principles of conservation of volume, momentum and mass, predicts surface elevation, current velocity and salinity. The water quality model, based on the conservation of mass alone, predicts eight parameters; dissolved oxygen (DO), chlorophyll 'a', carbonaceous biochemical oxygen demand (CBOD), organic nitrogen, ammonia nitrogen, nitrite-nitrate nitrogen, organic phosphorus and inorganic phosphorus. The model equations were solved using a two time level, finite difference scheme. The hydrodynamic model was calibrated and verified using …


Life History, Population Dynamics And Yield-Per-Recruit Modeling Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Area, Luiz R. Barbieri Jan 1993

Life History, Population Dynamics And Yield-Per-Recruit Modeling Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Area, Luiz R. Barbieri

Dissertations, Theses, and Masters Projects

Otoliths, scales, dorsal spines, and pectoral fin rays, of Atlantic croaker, Micropogonias undulatus, were compared for legibility of presumed annuli and precision in repeated readings, to determine the best structure for ageing. Marks on transverse otolith sections were easiest to read and showed the best agreement between readings. Fish collected in Chesapeake Bay and in Virginia and North Carolina coastal waters during 1988-1991 were then aged using otolith sections. Ages 1-8 were recorded, but eight-year-old fish were rare. Marginal increment analysis showed that for ages 1-7 annuli are formed once a year during the period April-May. Otolith age readings were …


The Structure Of The Holocephalan Head And The Relationships Of The Chondrichthyes, Eileen D. Grogan Jan 1993

The Structure Of The Holocephalan Head And The Relationships Of The Chondrichthyes, Eileen D. Grogan

Dissertations, Theses, and Masters Projects

The interrelationship of the chondrichthyan subclasses is evaluated based on divergence in the nature of the suspensorium, the preorbital cranial anatomy, the distribution of major venous sinuses and localization of hematopoietic tissue. The anatomy of representative extant taxa was examined by radiography and/or dissection. Fossil selachians, paraselachians, and holocephalans of the Bear Gulch of Montana, U.S.A. (Mississippian, Namurian E2B) were studied for evidence of vascular pigmentation, suspensorium, and cranial, branchial, and pectoral anatomy. These studies validate the suspensorial condition of autodiastyly and suggest autodiastyly is a fundamental condition involved in the basic radiation of Chondrichthyes. The plesiomorphous condition of all …


Distribution Of Organochlorine Pollutants In Sea Turtles, Mary J. Rybitski Jan 1993

Distribution Of Organochlorine Pollutants In Sea Turtles, Mary J. Rybitski

Dissertations, Theses, and Masters Projects

No abstract provided.


An Integration Of Case-Based And Model-Based Reasoning And Its Application To Physical System Faults, Stamos T. Karamouzis Jan 1993

An Integration Of Case-Based And Model-Based Reasoning And Its Application To Physical System Faults, Stamos T. Karamouzis

Dissertations, Theses, and Masters Projects

Case-Based Reasoning (CBR) systems solve new problems by finding stored instances of problems similar to the current one, and by adapting previous solutions to fit the current problem, taking into consideration any differences between the current and previous situations. CBR has been proposed as a more robust and plausible model of expert reasoning than the better-known rule-based systems.;Current CBR systems have been used in planning, engineering design, and memory organization. There has been minimal work, however, in the area of reasoning about physical systems. This type of reasoning is a difficult task, and every attempt to automate the process must …


A Study Of Molecular Order And Motion In Nematic Liquid Crystal Mixtures, Jon Michael Goetz Jan 1993

A Study Of Molecular Order And Motion In Nematic Liquid Crystal Mixtures, Jon Michael Goetz

Dissertations, Theses, and Masters Projects

Materials which flow like fluids, but possess anisotropic properties like molecular crystals, are called 'liquid crystals'. Studies of liquid crystals contribute to our understanding of how molecular orientation influences macroscopic properties. This thesis presents experimental and theoretical investigations of molecular order and dynamics in nematic liquid crystal systems. First, deuterium nuclear magnetic resonance is used to determine the degree of orientational order of both components of a liquid crystal mixture simultaneously. The temperature dependence of the four order parameters is interpreted using a newly developed mean field theory of nematic binary mixtures composed of biaxial molecules. Next, mean field theory …


A Measurement Of The Branching Ratio Of Long-Lived Neutral Kaon Going To Positive Muon Negative Muon, Michael Thomas Witkowski Jan 1993

A Measurement Of The Branching Ratio Of Long-Lived Neutral Kaon Going To Positive Muon Negative Muon, Michael Thomas Witkowski

Dissertations, Theses, and Masters Projects

The branching ratio $B(K\sbsp{L}{0} \to \mu\sp+\mu\sp-)$ has been measured using data obtained during running periods in 1988, 1989 and 1990. The data obtained in the 1990 running period are the latest and last from BNL experiment E791. During the three running periods, 87, 274 and 346 respective candidate events were observed, forming an overall sample of 707 $\mu\sp+\mu\sp-$ events. This number represents the largest sample to-date of $K\sbsp{L}{0} \to \mu\sp+\mu\sp-$ events. The result for the branching fraction using the total data set is $B(K\sbsp{L}{0} \to \mu\sp+\mu\sp-)$ = (6.86 $\pm$ 0.37) $\times$ 10$\sp{-9}$. This result is very near the unitarity bound …


The Dynamics Of An Oligohaline, Macrofaunal, Fouling Community, Michelle Lynne Thompson Neubauer Jan 1993

The Dynamics Of An Oligohaline, Macrofaunal, Fouling Community, Michelle Lynne Thompson Neubauer

Dissertations, Theses, and Masters Projects

No abstract provided.


The Relationship Between Dominant Macrobenthos And Cyclical Hypoxia In The Lower York River, R. Joseph Neubauer Jan 1993

The Relationship Between Dominant Macrobenthos And Cyclical Hypoxia In The Lower York River, R. Joseph Neubauer

Dissertations, Theses, and Masters Projects

No abstract provided.


Boundary Layer Structure In Homogeneous Tidal Flows: A Theoretical And Numerical Study, Jian Shen Jan 1993

Boundary Layer Structure In Homogeneous Tidal Flows: A Theoretical And Numerical Study, Jian Shen

Dissertations, Theses, and Masters Projects

No abstract provided.


In Situ Dielectric Monitoring And Kinetic Analysis Of Phase Separation, Theodore Joon Kim Jan 1993

In Situ Dielectric Monitoring And Kinetic Analysis Of Phase Separation, Theodore Joon Kim

Dissertations, Theses, and Masters Projects

No abstract provided.


Characterization Of Epoxy Resins For Use In The Resin Transfer Molding Process, Christina Kaye Short Jan 1993

Characterization Of Epoxy Resins For Use In The Resin Transfer Molding Process, Christina Kaye Short

Dissertations, Theses, and Masters Projects

No abstract provided.


Participation Of Alkenylboronate Esters In [2+2] Enone-Olefin Photocycloadditions, William Charles Lappenbusch Jan 1993

Participation Of Alkenylboronate Esters In [2+2] Enone-Olefin Photocycloadditions, William Charles Lappenbusch

Dissertations, Theses, and Masters Projects

No abstract provided.


The Synthesis Of N,N-Disubstituted Hydroxylamines Via Rearrangement Reactions Between Trialkylboranes And Nitrones, Stacie M. Cook Jan 1993

The Synthesis Of N,N-Disubstituted Hydroxylamines Via Rearrangement Reactions Between Trialkylboranes And Nitrones, Stacie M. Cook

Dissertations, Theses, and Masters Projects

No abstract provided.


Synthesis Of Boron-Substituted Isoxazolidines By Reaction Of Nitrones With Alkenyl Boronate Esters, Kevin P. Gwaltney Jan 1993

Synthesis Of Boron-Substituted Isoxazolidines By Reaction Of Nitrones With Alkenyl Boronate Esters, Kevin P. Gwaltney

Dissertations, Theses, and Masters Projects

No abstract provided.


Dielectric Relaxation In Controlled Pore Glass, David Brian Faddis Jan 1993

Dielectric Relaxation In Controlled Pore Glass, David Brian Faddis

Dissertations, Theses, and Masters Projects

No abstract provided.


Cross-Linking Additives As Smoke Suppressants For Poly(Vinyl Chloride), Steven Alfred Terranova Jan 1993

Cross-Linking Additives As Smoke Suppressants For Poly(Vinyl Chloride), Steven Alfred Terranova

Dissertations, Theses, and Masters Projects

No abstract provided.


Interspecific And Intraspecific Variability In Placoid Scale Morphology In Relation To Body Form Variability In Squaliformes, Christopher R. Tabit Jan 1993

Interspecific And Intraspecific Variability In Placoid Scale Morphology In Relation To Body Form Variability In Squaliformes, Christopher R. Tabit

Dissertations, Theses, and Masters Projects

An ontogenetic series of nine species; Centrophorus granulosus, Centroscymnus coelolepis, Dalatias licha, Deania calcea, Echinorhinus cookei, Isistius brasiliensis, Oxynotus centrina and Squalus acanthias were studied to determine swimming capabilities, boundary-layer flow conditions and placoid scale functional morphologies. Body morphometric variables included the girth and the distance from snout to the orbitals, origin of the median and paired fins, and the caudal peduncle, body and fin surface area, fin aspect ratios and caudal fin angles. Placoid scales were sampled from sixteen regions across the body. Morphometric variables included the number of scales per area of integument, scale crown width, length and …


Amorphometric And Meristic Study Of The Halfbeak, Hyporhamphus Unifasciatus (Teleostei: Hemiramphidae) From The Western Atlantic, With The Description Of A New Species, Heidi M. Banford Jan 1993

Amorphometric And Meristic Study Of The Halfbeak, Hyporhamphus Unifasciatus (Teleostei: Hemiramphidae) From The Western Atlantic, With The Description Of A New Species, Heidi M. Banford

Dissertations, Theses, and Masters Projects

No abstract provided.


Responses Of Cytochrome P450ia In Freshwater Fish Exposed To Pulp Mill Effluents In Experimental Stream Channels, Laura Anne Bankey Jan 1993

Responses Of Cytochrome P450ia In Freshwater Fish Exposed To Pulp Mill Effluents In Experimental Stream Channels, Laura Anne Bankey

Dissertations, Theses, and Masters Projects

No abstract provided.


Growth Response Of Eelgrass (Zostera Marina L) To Root-Rhizome And Whole Plant Exposure To Atrazine, Arthur C. Schwarzschild Jan 1993

Growth Response Of Eelgrass (Zostera Marina L) To Root-Rhizome And Whole Plant Exposure To Atrazine, Arthur C. Schwarzschild

Dissertations, Theses, and Masters Projects

No abstract provided.


Dynamics Of Fish Assemblages Associated With An Offshore Artificial Reef In The Southern Mid-Atlantic Bight, Aaron J. Adams Jan 1993

Dynamics Of Fish Assemblages Associated With An Offshore Artificial Reef In The Southern Mid-Atlantic Bight, Aaron J. Adams

Dissertations, Theses, and Masters Projects

No abstract provided.


A Study Of The Guiding Center Approximation, Qun Yao Jan 1993

A Study Of The Guiding Center Approximation, Qun Yao

Dissertations, Theses, and Masters Projects

A Hamiltonian treatment for the motion of a charged particle in a toroidal magnetic field is given. Assuming the plasma equilibrium, Boozer coordinates are used. The Hamiltonian of the exact trajectory is given in the guiding center coordinates. The higher order corrections to the standard drift Hamiltonian are derived. It is shown that the exact Hamiltonian depends on both the field strength and the shape of the magnetic surfaces (the metric of Boozer coordinates) while the standard drift Hamiltonian depends only on the field strength. The first order correction to the standard drift Hamiltonian, in gyroradius to system size, depends …


End-To-End Analysis Of Hexagonal Vs Rectangular Sampling In Digital Imaging Systems, John Clifton Burton Ii Jan 1993

End-To-End Analysis Of Hexagonal Vs Rectangular Sampling In Digital Imaging Systems, John Clifton Burton Ii

Dissertations, Theses, and Masters Projects

The purpose of this study was to compare two common methods for image sampling in digital image processing: hexagonal sampling and rectangular sampling. The two methods differ primarily in the arrangement of the sample points on the image focal plane. In order to quantitatively compare the two sampling methods, a mathematical model of an idealized digital imaging system was used to develop a set of mean-squared-error fidelity loss metrics. The noiseless continuous/discrete/continuous end-to-end digital imaging system model consisted of four independent components: an input scene, an image formation point spread function, a sampling function, and a reconstruction function. The metrics …


Photoabsorption Spectra Of Hydrogen In Magnetic Fields, John A. Shaw Jan 1993

Photoabsorption Spectra Of Hydrogen In Magnetic Fields, John A. Shaw

Dissertations, Theses, and Masters Projects

Measurements of the absorption spectrum of atomic H in strong magnetic fields have been analyzed. The measurements, performed by the Bielefeld, Germany experimental group, investigated the photoabsorption to levels near the ionization threshold in magnetic fields ranging from 2.7 to 6 Tesla. Taking advantage of a classical scaling law, the photon energy and the magnetic field strength were varied simultaneously in the experiment and the absorption rate vs. B{dollar}\sp{lcub}-1/3{rcub}{dollar} at fixed scaled-energy, {dollar}\varepsilon{dollar} = E/(B/B{dollar}\sb{lcub}\rm o{rcub})\sp{lcub}2/3{rcub}{dollar} was measured. The absorption rate was observed to exhibit sinusoidal fluctuations which we correlate with closed classical orbit of the electron. A Fourier transformation …


Flush Communication Channels: Effective Implementation And Verification, Tracy Kay Camp Jan 1993

Flush Communication Channels: Effective Implementation And Verification, Tracy Kay Camp

Dissertations, Theses, and Masters Projects

Flush communication channels, or F-channels, generalize more conventional asynchronous communication paradigms. A distributed system which uses an F-channel allows a programmer to define the delivery order of each message in relation to other messages transmitted on the channel. Unreliable datagrams and FIFO (first-in-first-out) communication channels have strictly defined delivery semantics. No restrictions are allowed on message delivery order with unreliable datagrams--message delivery is completely unordered. FIFO channels, on the other hand, insist messages are delivered in the order of their transmission. Flush channels can provide either of these delivery order semantics; in addition, F-channels allow the user to define the …


Fourier Analysis Of Frequency Domain Discrete Event Simulation Experiments, Mousumi Mitra Hazra Jan 1993

Fourier Analysis Of Frequency Domain Discrete Event Simulation Experiments, Mousumi Mitra Hazra

Dissertations, Theses, and Masters Projects

Frequency Domain Experiments (FDEs) were first used in discrete-event simulation to perform system parameter sensitivity analysis for factor screening in stochastic system simulations. FDEs are based on the intuitive assertion that if one or more system parameters are oscillated at fixed frequencies throughout a simulation run, then oscillations at the same frequencies will be induced in the system's response. Spectral (Fourier) analysis of these induced oscillations is then used to characterize and analyze the system. Since their introduction 12 years ago, significant work has been done to extend the applicability of FDEs to regression analysis, simulation optimization and gradient estimation. …


The Effects Of Granularity On The Microwave Surface Impedance Of High Kappa Superconductors, Stephen Keith Remillard Jan 1993

The Effects Of Granularity On The Microwave Surface Impedance Of High Kappa Superconductors, Stephen Keith Remillard

Dissertations, Theses, and Masters Projects

The microwave surface impedance of granular high temperature superconductors is an important figure of merit for technological applications. Because the behavior of the granular materials deviates significantly from that of the ideal defect free superconductors, the loss mechanisms are not fully understood. This dissertation seeks to quantify the contribution of granularity to centimeter wave and millimeter wave losses. By understanding these losses, the superconductive coupling between neighboring grains can also be understood.;The weakly coupled grain model is used as a phenomenological description of the microwave surface impedance. The granular superconducting surface is modelled as an effective resistively shunted Josephson junction. …