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Articles 1 - 28 of 28

Full-Text Articles in Physical Sciences and Mathematics

Juvenile Pelagic Fish Communities In The Mattaponi And Pamunkey Rivers, Virginia, Steffany Dawson Jan 1992

Juvenile Pelagic Fish Communities In The Mattaponi And Pamunkey Rivers, Virginia, Steffany Dawson

Dissertations, Theses, and Masters Projects

No abstract provided.


Survival Of Juvenile Queen Conch, Strombus Gigas, In Natural Habitats: Impact Of Prey, Predator And Habitat Features, Livingston Sinclair Marshall Jr Jan 1992

Survival Of Juvenile Queen Conch, Strombus Gigas, In Natural Habitats: Impact Of Prey, Predator And Habitat Features, Livingston Sinclair Marshall Jr

Dissertations, Theses, and Masters Projects

In this dissertation, I experimentally examine predation-induced mortality upon juvenile queen conch, Strombus gigas, and assess the importance of select habitat predator and conch characteristics affecting predation intensity. Experiments were conducted during the summer and early fall of 1987, 1988, 1990 and 1991 in seagrass beds and adjacent sand flats near Lee Stocking Island, Exuma Cays, Bahamas. These experiments indicate that various factors act interactively to produce habitat-specific mortality rates in queen conch due to predation. These include (1) habitat type, whereby seagrass beds offer some protection; (2) local population dynamics, such that populated seagrass beds appear to enhance conch …


A Comparison Of Grow-Out Methods For The Bay Scallop, Argopecten Irradians Irradians, At Two Sites In Virginia, Mark J. Brotman Jan 1992

A Comparison Of Grow-Out Methods For The Bay Scallop, Argopecten Irradians Irradians, At Two Sites In Virginia, Mark J. Brotman

Dissertations, Theses, and Masters Projects

No abstract provided.


Intelligent Processing Of Pmr-15, Sean Michael Hart Jan 1992

Intelligent Processing Of Pmr-15, Sean Michael Hart

Dissertations, Theses, and Masters Projects

No abstract provided.


A Helium Discharge Detector For The Determination Of Organosulfur And Phosphorus Compounds, Tamara L. Tieman Jan 1992

A Helium Discharge Detector For The Determination Of Organosulfur And Phosphorus Compounds, Tamara L. Tieman

Dissertations, Theses, and Masters Projects

No abstract provided.


The Imidization Reactions Of Pmr-15 Polyimide, Kerri Ann Robillard Jan 1992

The Imidization Reactions Of Pmr-15 Polyimide, Kerri Ann Robillard

Dissertations, Theses, and Masters Projects

No abstract provided.


Code Generation Using A Backtracking Lr Parser, Laurie Anne Smith King Jan 1992

Code Generation Using A Backtracking Lr Parser, Laurie Anne Smith King

Dissertations, Theses, and Masters Projects

Although the parsing phase of the modern compiler has been automated in a machine independent fashion, the diversity of computer architectures inhibits automating the code generation phase. During code generation, some intermediate representation of a source program is transformed into actual machine instructions. The need for portable compilers has driven research towards the automatic generation of code generators.;This research investigates the use of a backtracking LR parser that treats code generation as a series of tree transformations.


Design And Analysis Techniques For Concurrent Blackboard Systems, John William Mcmanus Jan 1992

Design And Analysis Techniques For Concurrent Blackboard Systems, John William Mcmanus

Dissertations, Theses, and Masters Projects

Blackboard systems are a natural progression of Artificial Intelligence based systems into a more powerful problem solving technique. They provide a way for several highly specialized knowledge sources to cooperate to solve large, complex problems. Blackboard systems incorporate the concepts developed by rule-based and expert systems programmers and include the ability to add conventionally coded knowledge sources. The small and specialized knowledge sources are easier to develop and test, and are hosted on hardware specifically suited to the task that they are solving.;Designing and developing blackboard systems is a difficult process. The designer is attempting to balance several conflicting goals …


Role Of Habitat Features And Chemical Cues In Substrate Selection By Blue Crab Megalopae: Evidence From Laboratory Experiments, Bruce Clare Layman Jan 1992

Role Of Habitat Features And Chemical Cues In Substrate Selection By Blue Crab Megalopae: Evidence From Laboratory Experiments, Bruce Clare Layman

Dissertations, Theses, and Masters Projects

No abstract provided.


Survival And Abundance Of Juvenile Caribbean Spiny Lobster: Effects Of Shelter Size And Geographic Location, Jonathon Daniel Mintz Jan 1992

Survival And Abundance Of Juvenile Caribbean Spiny Lobster: Effects Of Shelter Size And Geographic Location, Jonathon Daniel Mintz

Dissertations, Theses, and Masters Projects

No abstract provided.


Completion Of Partial Operator Matrices, M.(Mihaly) Bakonyi Jan 1992

Completion Of Partial Operator Matrices, M.(Mihaly) Bakonyi

Dissertations, Theses, and Masters Projects

This work concerns completion problems for partial operator matrices. A partial matrix is an m-by-n array in which some entries are specified and the remaining are unspecified. We allow the entries to be operators acting between corresponding vector spaces (in general, bounded linear operators between Hilbert spaces). Graphs are associated with partial matrices. Chordal graphs and directed graphs with a perfect edge elimination scheme play a key role in our considerations. A specific choice for the unspecified entries is referred to as a completion of the partial matrix. The completion problems studied here involve properties such as: zero-blocks in certain …


Shoreline Habitat Selection By Bald Eagles (Haliaeetus Leucocephalus) In A Non-Breeding Eagle Concentration-Area On The James River, Virginia, Kennedy H. Clark Jan 1992

Shoreline Habitat Selection By Bald Eagles (Haliaeetus Leucocephalus) In A Non-Breeding Eagle Concentration-Area On The James River, Virginia, Kennedy H. Clark

Dissertations, Theses, and Masters Projects

No abstract provided.


Verification Of Fault-Tolerant Clock Synchronization Systems, Paul S. Miner Jan 1992

Verification Of Fault-Tolerant Clock Synchronization Systems, Paul S. Miner

Dissertations, Theses, and Masters Projects

No abstract provided.


The Branching Fraction Of Long-Lived Kaon Going To Muon-Anti-Muon, Michael David Chapman Jan 1992

The Branching Fraction Of Long-Lived Kaon Going To Muon-Anti-Muon, Michael David Chapman

Dissertations, Theses, and Masters Projects

This thesis presents the results of a measurement of the branching fraction of the $K\sb{L}\to\mu\bar{\mu}$ decay. This decay is scGIM supressed in the Standard Model, and provides a useful test of that model. Additionally, the degree of deviation from the unitary limit provides a useful test for several other models. The experiment was performed at the Brookhaven National Laboratory Alternating Gradient Synchrotron facility. The apparatus consisted of a two-magnet mass spectrometer, together with dual electromagnetic and muon particle identification systems. A total of 281 $K\sb{L}\to\mu\bar{\mu}$ events were observed. Normalizing to the 15,768 $K\sb{L}\to\pi\bar{\pi}$ events observed results in a branching fraction …


Land Use And Wetland Function: A Sensitivity Analysis Of The Vims Nontidal Wetland Functional Assessment Method, Martha Craig Jan 1992

Land Use And Wetland Function: A Sensitivity Analysis Of The Vims Nontidal Wetland Functional Assessment Method, Martha Craig

Dissertations, Theses, and Masters Projects

No abstract provided.


Taxonomy Of Larval Blennioidei Of Belize, Central America, Martin Ray Cavalluzzi Jan 1992

Taxonomy Of Larval Blennioidei Of Belize, Central America, Martin Ray Cavalluzzi

Dissertations, Theses, and Masters Projects

No abstract provided.


Allozyme Analysis Of Billfish Population Structure, Lee W. Morgan Jan 1992

Allozyme Analysis Of Billfish Population Structure, Lee W. Morgan

Dissertations, Theses, and Masters Projects

No abstract provided.


Formation And Desorption Of Negative Ions From Metal Surfaces, Douglas Hugh Baker Jan 1992

Formation And Desorption Of Negative Ions From Metal Surfaces, Douglas Hugh Baker

Dissertations, Theses, and Masters Projects

Investigations of negative ion and electron emission from gas-covered metal surfaces due to the impact of low energy (30-300 eV) positive ions and, separately, photons (2-5 eV) are presented. In both cases, the negative ion formation process is thought to occur via electron tunneling from the surface or its substrate to a sputtered or photodesorbed neutral atom or molecule.;In particular, absolute total negative ion and electron yields for collisions of positive alkali ions with a gas-covered Mo substrate have been measured. Mass analysis of the sputtered negative ions show that O{dollar}\sb2\sp-{dollar} is the dominant ion at low impact energies. This …


Distribution, Abundance, And Behavior Of The Cownose Ray, Rhinoptera Bonasus (Mitchill 1815), In Lower Chesapeake Bay, Robert A. Blaylock Jan 1992

Distribution, Abundance, And Behavior Of The Cownose Ray, Rhinoptera Bonasus (Mitchill 1815), In Lower Chesapeake Bay, Robert A. Blaylock

Dissertations, Theses, and Masters Projects

Aspects of the ecology of the cownose ray, Rhinoptera bonasus, in the lower Chesapeake Bay and its tributaries were studied using aerial surveys, biotelemetry, and examination of stomach contents. The Chesapeake Bay was surveyed by airplane during 1986-1989, to examine the distribution of cownose rays and estimate their abundance using line transect methods. Cownose rays resided in Chesapeake Bay throughout the summer months, entering in early June and emigrating in late September. They were usually absent, or nearly so, by late October. Mean monthly abundance ranged from none present in May and November, to a September average of 9.3 &\cdot& …


Intentional Introductions Of Non-Indigenous Species: A Case Study Of Policy And Management Affecting Crassostrea Gigas, Gwynne D. Brown Jan 1992

Intentional Introductions Of Non-Indigenous Species: A Case Study Of Policy And Management Affecting Crassostrea Gigas, Gwynne D. Brown

Dissertations, Theses, and Masters Projects

No abstract provided.


An Investigation Of The Late Pleistocene Paleochannel Systems In The Continental Shelf, South Of Chesapeake Bay Mouth, Ziqiang Chen Jan 1992

An Investigation Of The Late Pleistocene Paleochannel Systems In The Continental Shelf, South Of Chesapeake Bay Mouth, Ziqiang Chen

Dissertations, Theses, and Masters Projects

No abstract provided.


Generic Identification And Patterns Of External Pigment In Larval Gobies (Pisces: Gobiidae) From The Belize Barrier Reef, Elizabeth D. Maddox Jan 1992

Generic Identification And Patterns Of External Pigment In Larval Gobies (Pisces: Gobiidae) From The Belize Barrier Reef, Elizabeth D. Maddox

Dissertations, Theses, and Masters Projects

No abstract provided.


Measurement Of The Carbon And Nitrogen Densities Of The Marine Heterotrophic Flagellate Paraphysomonas Sp, Yongsik Sin Jan 1992

Measurement Of The Carbon And Nitrogen Densities Of The Marine Heterotrophic Flagellate Paraphysomonas Sp, Yongsik Sin

Dissertations, Theses, and Masters Projects

No abstract provided.


Synthesis And Inclusion Of 1-(5-Cyanonaphthyl) Diazomethane With B-Cyclodextrin, Scott Tobias Forrest Jan 1992

Synthesis And Inclusion Of 1-(5-Cyanonaphthyl) Diazomethane With B-Cyclodextrin, Scott Tobias Forrest

Dissertations, Theses, and Masters Projects

No abstract provided.


Modelling Of Zinc Accumulation In The American Oyster, Crassostrea Virginica (Gmelin), Cheol Mo Jan 1992

Modelling Of Zinc Accumulation In The American Oyster, Crassostrea Virginica (Gmelin), Cheol Mo

Dissertations, Theses, and Masters Projects

A model of zinc accumulation by the American oyster, Crassostrea virginica, is developed by relating in-situ zinc body burden to time-integration of uptake. Short-term uptake rates are estimated in laboratory by introducing &\sp{lcub}65{rcub}&Zn to oysters of various weights in aquaria with salinities of 18&\perthous& and 12&\perthous&. Uptake of &\sp{lcub}65{rcub}&Zn by an oyster: (1) varies as a power function of the body weight (soft tissue dry weight) of the oyster (&dy\over{lcub}dt{rcub}& = kW&\sp{lcub}\beta{rcub}&), (2) is inversely related to the salinity of ambient water, and (3) increases linearly with ambient concentration. Zinc body burdens of oysters of various weights from oyster beds …


Painleve Singularity Analysis Applied To Charged Particle Dynamics During Reconnection, Jay Walter Larson Jan 1992

Painleve Singularity Analysis Applied To Charged Particle Dynamics During Reconnection, Jay Walter Larson

Dissertations, Theses, and Masters Projects

For a plasma in the collisionless regime, test-particle modelling can lend some insight into the macroscopic behavior of the plasma, e.g conductivity and heating. A common example for which this technique is used is a system with electric and magnetic fields given by B = {dollar}\delta y{dollar}cx x + xcx y + {dollar}\gamma{dollar}cx z and E = {dollar}\epsilon{dollar}cx z, where {dollar}\delta{dollar}, {dollar}\gamma{dollar}, and {dollar}\epsilon{dollar} are constant parameters. This model can be used to model plasma behavior near neutral lines, ({dollar}\gamma{dollar} = 0), as well as current sheets ({dollar}\gamma{dollar} = 0, {dollar}\delta{dollar} = 0). The integrability properties of the particle motion …


Quasilinear Theory Of Laser-Plasma Interactions, Alastair John Neil Jan 1992

Quasilinear Theory Of Laser-Plasma Interactions, Alastair John Neil

Dissertations, Theses, and Masters Projects

The interaction of a high intensity laser beam with a plasma is generally susceptible to the filamentation instability due to nonuniformities in the laser profile. In ponderomotive filamentation high intensity spots in the beam expell plasma by ponderomotive force, lowering the local density, causing even more light to be focused into the already high intensity region. The result--the beam is broken up into a filamentary structure.;Several optical smoothing techniques have been proposed to eliminate this problem. In the Random Phase Plates (RPS) approach, the beam is split into a very fine scale, time-stationary interference pattern. The irregularities in this pattern …


The Effect Of A One-Meter Sea-Level Rise On Tidal Wetlands In Gloucester County, Virginia, Paula Lindsey Hill Jan 1992

The Effect Of A One-Meter Sea-Level Rise On Tidal Wetlands In Gloucester County, Virginia, Paula Lindsey Hill

Dissertations, Theses, and Masters Projects

No abstract provided.