Physical Sciences and Mathematics Commons^™

Post-Glacial Sedimentation In A River -Dominated Epicontinental Shelf: The Yellow Sea Example, Jing-Pu Liu

Dissertations, Theses, and Masters Projects

The North Yellow Sea (NYS) and South Yellow Sea (SYS), stretching from the Bohai Sea in the north to the East China Sea (ECS) in the south, represents an end member of modern epicontinental seas. Because of its shallow depths, the Yellow Sea was entirely exposed subaerially during the last glacial maximum. The new post-glacial sea-level curve derived from an extensive local dataset shows a series of rapid flooding events (12--45 mm/y), separated by a series of slow rises (2--6 mm/y). By about 15 ka, sea level had reached -100 m, and seawater entered the SYS. A rapid rise during …

Modeling Of Critically-Stratified Gravity Flows: Application To The Eel River Continental Shelf, Northern California, Malcolm E. Scully

Dissertations, Theses, and Masters Projects

An analytical and numerical model are presented and applied to predict gravitydriven transport and deposition of fluid mud layers that form within the wave boundary layer on the continental shelf off the Eel River in northern California. Observations indicate that following floods of the Eel River down-slope transport of fluid mud trapped within the wave boundary layer is the dominant across-shelf transport mechanism. The models are based upon the assumption that following significant floods, an abundant supply of easily suspended fine sediment is delivered to the coastal ocean, allowing a negative feedback mechanism to maintain the near-bed Richardson number at …

An Examination Of Potential Conflict Between Sav And Hard Clam Aquaculture In The Lower Chesapeake Bay, Helen Woods

Dissertations, Theses, and Masters Projects

Natural resource mangers may find themselves in a conflict of interest over the management of shallow subaqueous bottom when they attempt to promote both hard clam (Mercenaria mercenaria) aquaculture and the growth of submersed aquatic vegetation (SAV) (Zostera marina and Ruppia maritima). This project examines the issue of bottom use conflict along the Lower Eastern Shore of the Chesapeake Bay in a managerial and scientific context in an attempt to develop a solution to this conflict. First, it examines historical trends in clam aquaculture and SAV growth in the study area. Habitat suitability models are then developed to predict optimal …

Cobia (Rachycentron Canadum) Aquaculture: Captive Growth Rates And Product Quality Evaluation, David Patrick Kilduff

Dissertations, Theses, and Masters Projects

No abstract provided.

A Descriptive Study Of The Reproductive Biology Of The Veined Rapa Whelk (Rapana Venosa) In The Chesapeake Bay, Erica S. Westcott

Dissertations, Theses, and Masters Projects

No abstract provided.

Reproductive Biology Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay, Elizabeth Shaw Watkins

Dissertations, Theses, and Masters Projects

No abstract provided.

Gis Data: City Of Poquoson Shoreline Situation Report, Marcia Berman, Harry Berquist, Sharon Dewing, J. B. Glover, Carl Hershner, Tamia Rudnicky, Daniel E. Schatt, Kevin Skunda

Data

The Shoreline Management Model is a GIS spatial model that determines appropriate shoreline best management practices using available spatial data and decision tree logic. Available shoreline conditions used in the model include the presence or absence of tidal marshes, beaches, and forested riparian buffers, bank vegetation cover, bank height, wave exposure (fetch), nearshore water depth, and proximity of coastal development to the shoreline. The model output for shoreline best management practices is displayed in the locality Comprehensive Map Viewer. One GIS shapefile is developed that describes two arcs or lines representing practices in the upland area and practices at the …

Persistent Organic Pollutant Transport And Fate: Assessment By Molecular Tracers, Padma T. Venkatraman

Dissertations, Theses, and Masters Projects

Persistent organic pollutants (POPs) such as the organochlorine pesticide hexachlorocyclohexane (HCH) may undergo atmospheric transport and accumulate in regions remote from the source. It is important to develop techniques to help apportion source and identify transport or transformation processes to which HCHs and other mobile POPs may be subjected. Molecular tracers such as compound specific stable isotope and enantiomer ratios (ERs) may prove valuable in studying POP fate and transport. The objective of this study was to further develop the use of these two novel geochemical tools to evaluate the sources, transport and environmental fate of POPs, in the context …

Topics In Physics Beyond The Standard Model, Alfredo Aranda

Dissertations, Theses, and Masters Projects

In this dissertation we address three issues related to physics beyond the Standard model: flavor and the use of discrete gauge symmetries, the dynamical breaking of electroweak symmetry, and the addition of a U(1) gauge symmetry to the Standard model in order to suppress proton decay. We present: (i) A model of flavor based on the double tetrahedral group that leads to acceptable quark and lepton masses as well as mixing angles. Furthermore it gives solutions for the atmospheric and solar neutrino problems. (ii) A model of bosonic topcolor in which the breaking of electroweak symmetry occurs dynamically through the …

Broadcast Distributed Shared Memory, Philip Ragner Auld

Dissertations, Theses, and Masters Projects

Distributed shared memory (DSM) provides the illusion of shared memory processing to programs running on physically distributed systems. Many of these systems are connected by a broadcast medium network such as Ethernet. In this thesis, we develop a weakly coherent model for DSM that takes advantage of hardware-level broadcast. We define the broadcast DSM model (BDSM) to provide fine-grained sharing of user-defined locations. Additionally, since extremely weak DSM models are difficult to program, BDSM provides effective synchronization operations that allow it to function as a stronger memory. We show speedup results for a test suite of parallel programs and compare …

Characterizing And Monitoring Changes In State Of Polymers During Cure And Use -Aging, Andrew Orschel Meyer

Dissertations, Theses, and Masters Projects

Multi Angle Laser Light Scattering (MALLS) and Frequency Dependent Electromagnetic Sensing (FDEMS) provide unique characterizations of polymer systems during cure and use-aging. This research illustrates how MALLS is an extremely accurate technique for absolute characterization of macromolecules, giving molecular weight and size information that other widely used and accepted techniques are incapable of measuring. Application of MALLS to monitoring the changing state of a polyamide-11 system in a water aging environment led to the discovery of an equilibrium molecular weight which is the result of two competing reactions, hydrolysis-degradation and a newly discovered recombination-polymerization reaction. The discovery of this recombination …

Virtual Path Bandwidth Distribution And Capacity Allocation With Bandwidth Sharing, Karen Marie Anewalt

Dissertations, Theses, and Masters Projects

Broadband high-speed networks, such as B-ISDN, are expected to play a dominant role in the future of networking due to their capability to service a variety of traffic types with very different bandwidth requirements such as video, voice and data. to increase network efficiency in B-ISDN and other such connection oriented networks, the concept of a virtual path (VP) has been proposed and studied in the literature. A VP is a permanent or semi-permanent reservation of capacity between two nodes. Using VPs can potentially reduce call setup delays, simplify hardware, provide quality of service performance guarantees, and reduce disruption in …

Solid State Nmr Characterization Of Structural And Motional Parameter Distributions In Polyamidoammonium Dendrimers, Dariya Ivanovna Malyarenko

Dissertations, Theses, and Masters Projects

The characterization of narrow distributions of structural and motional parameters, and their evolution during the broad glass transition, is performed for deuterated PAMAM dendrimer salts using solid state NMR. The broadening of deuteron quadrupole echo (QE) lineshapes is consistent with the presence of narrow hydrogen bond length distribution (sigmar < 0.25 A) at the spacer amide and branching tertiary amine sites. The temperature dependent averaging of the experimental lineshapes is explained on the basis of fast planar librations in the dendrimer interior, and fast rotation and intermediate regime libration (in an asymmetric cone) of the dendrimer termini. The amplitudes of libration are temperature dependent and higher for low generation dendrimers, while librational rates show Arrhenius behavior only within the glass transition region. In this region, the width of log-normal distribution of rates increases with temperature at sites associated with chlorine counterions. The largest distributions are still less than one order of magnitude wide, unlike the dendrimer in solution or the linear polymers. Interpenetrated low generations (G < 3), uniform intermediate generations (G = 3--5) with surface network, and backfolded high generations (G > 5), are distinguished by interior and termini dynamics.;In the regime of fast motion QE lineshapes are highly sensitive to the presence of narrow structural and motional parameter distributions, and provide constraints on motional geometry independent of rates. The precise characterization of narrow log-normal rate distributions in the intermediate regime can be …

Single Positive Pion Electroproduction In The First And Second Resonance Regions Using Clas, Hovanes Egiyan

Dissertations, Theses, and Masters Projects

The study of single pion electroproduction can provide valuable information on the structure of the nucleon and its excited states. Although these reactions have been studied for decades, never has the npi + channel been measured over the complete phase space of the reaction. The CEBAF Large Acceptance Spectrometer (CLAS) located in Hall B of Jefferson Lab is well-suited for conducting these measurements. The CLAS data were taken using a 1.515 GeV electron beam incident on a liquid H 2 target. The cross sections have been extracted, and their &phis;-dependence has been fit to obtain the sigmaTT, sigma TL and …

Characterization Of Cyclic And Linear Dipeptides, Christine Michelle Howard

Dissertations, Theses, and Masters Projects

No abstract provided.

The Synthesis And Characterization Of Cu(I) Networks With Heterocyclic Bridging Ligands, Jonathan Timothy Maeyer

Dissertations, Theses, and Masters Projects

No abstract provided.

Measurement Of The Strange Sea Of The Proton, Gary A. Rutledge

Dissertations, Theses, and Masters Projects

The differential cross section for elastic scattering of longitudinally-polarized electrons from protons exhibits a parity-violating asymmetry, due to the interference between weak and electromagnetic amplitudes. The asymmetry is extracted from the detector counting rates as APV = ( Dr - Dl)/(Dr + D l) where Drl are related to the right (left) differential cross sections sigmar, sigmal respectively. Thus APV = (sigmar - sigma l)/(sigmar + sigmal) for right-handed and left-handed electrons. This asymmetry is sensitive to the presence of strange sea quarks in the proton, in particular to the strange vector matrix elements GsE and GsM .;In an experiment …

Gis Data: Essex County And The Town Of Tappahannock Shoreline Situation Report, Marcia Berman, Harry Berquist, Sharon Dewing, J. B. Glover, Carl Hershner, Tamia Rudnicky, Dan Schatt, Kevin Skunda

Data

The data inventory developed for the Shoreline Situation Reports are based on a three-tiered shoreline assessment approach. This assessment characterizes conditions in the shorezone observed from a small boat moving along the shoreline. Handheld GPS units record data observations in the field. The three tiered shoreline assessment approach divides the shorezone into three regions:

1. the immediate riparian zone, evaluated for land use

2. the bank, evaluated for height, stability, cover and natural protection

3. the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes.

Three GIS coverages are generated from the collection technique. The essex_lubc coverage are features …

Virginia Marine Infrastructure Needs Assessment, Thomas J. Murray

Reports

In an effort to support Virginia's application for federal grant funds under the Department of Interior's "Boating Infrastructure Grant Program" (Grants), the Marina Technical Advisory Program (MTAP) at the Virginia Institute of Marine Science has undertaken assessment of the state's recreational boating infrastructure needs.1 A total of$32 million has been authorized over four years to fund this new program. It is designed to help states develop and maintain facilities for transient, non-trailerable (26' and over) recreational boats. The Virginia Department of Health (VDOH) is providing overall leadership in the Boating Infrastructure Grants process, supported by the Virginia Sea Grant College …

Virginia Game Fish Tagging Program Annual Report 2000, John A. Lucy, C.M. Bain Iii

Reports

The Virginia Game Fish Tagging Program (VGFTP), in its sixth year during 2000, systematically trains and assists anglers in tagging a select number of species important to Virginia's marine recreational fishery and maintains the resulting tagging database. A cooperative project of the Virginia Marine Resources Commission and the Virginia Institute of Marine Science (VIMS), the program is primarily funded with revenues from Virginia's saltwater recreational fishing license funds (Recreational Fishing Development Fund). In addition, support for the program is provided by Virginia's Sea Grant Marine Advisory Program at VIMS.

Asymptotic Analysis Of Buffered Calcium Diffusion Near A Point Source, Arthur Sherman, Gregory D. Smith, Longxiang Dai, Robert M. Miura

Arts & Sciences Articles

The "domain" calcium (Ca2+) concentration near an open Ca2+ channel can be mod- eled as buffered diffusion from a point source. The concentration profiles can be well approximated by hemispherically symmetric steady-state solutions to a system of reaction-diffusion equations. After nondimensionalizing these equations and scaling space so that both reaction terms and the source amplitude are 0(1), we identify two dimensionless parameters, Cc and Eb, that correspond to the diffusion coefficients of dimensionless Ca2+ and buffer, respectively. Using perturbation methods, we derive approximations for the Ca2+ and buffer profiles in three asymptotic limits: (1) an "excess buffer approximation" (EBA), where …

Riparian Forest Buffer Restoration Targeting For The Rappahannock River Watershed, Anne Newsome, Carl Hershner, Dan Schatt, Virginia Institute Of Marine Science, Wetlands Program

Reports

No abstract provided.

Summary Tables: Richmond County, Virginia Shoreline Inventory Report, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).

Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 September 1999 - 31 October 2000, Philip W. Sadler, Robert E. Harris, John E. Olney, Robert J. Latour

Reports

To document continued compliance with Federal law, the Anadromous Fishes Program of the Virginia Institute of Marine Science (VIMS) has monitored the size and age composition, sex ratio and maturity schedules of the spawning striped bass stock in the Rappahannock River since December 1981 utilizing commercial pound nets and, since 1991, variable-mesh experimental gill nets. Spawning stock assessment was expanded to include the James River in 1994 utilizing 11 commercial fyke nets and variable-mesh experimental gill nets. The use of fyke nets was discontinued after 1997. In conjunction with the monitoring studies, tagging programs have been conducted in the James …

Middlesex County Shoreline Situation Report, Marcia Berman, Harry Berquist, Sharon Dewing, J. B. Glover, Carl Hershner, Tamia Rudnicky, Daniel E. Schatt, Kevin Skunda

Reports

No abstract provided.

Modeling Distinct Vertical Biogeochemical Structure Of The Black Sea: Dynamical Coupling Of The Oxic, Suboxic, And Anoxic Layers, T Oguz, Hw Ducklow, P Malanotte-Rizzoli

VIMS Articles

A one-dimensional, vertically resolved, physical-biogeochemical model is used to provide a unified representation of the dynamically coupled oxic-suboxic-anoxic system for the interior Black Sea. The model relates the annual cycle of plankton production in the form of a series of successive phytoplankton, mesozooplankton, and higher consumer blooms to organic matter generation and to the remineralization-ammonification-nitrification-dentrification chain of the nitrogen cycle as well as to anaerobic sulfide oxidation in the suboxic-anoxic interface zone. The simulations indicate that oxygen consumption during remineralixation and nitrification, together with a lack of ventilation of subsurface waters due to the presence of strong stratification, are the …

Virginia Marina Needs Assessment: Summary Statistics, Thomas J. Murray

Reports

In an effort to support Virginia's application for federal grant funds under the Department of Interior's "Boating Infrastructure Grant Program" (Grants), the Marina Technical Advisory Program (MT AP) at the Virginia Institute of Marine Science has undertaken assessment of the state's recreational boating infrastructure needs.1 A total of $32 million has been authorized over four years to fund this new program. It is designed to help states develop and maintain facilities for transient non-trailerable (26' and over) recreational boats. The Virginia Department of Health (VDOH) is providing overall leadership in the Boating Infrastructure Grants process supported by the The Virginia …

The Virginia Wetlands Report Vol. 15, No. 3, Virginia Institute Of Marine Science

Virginia Wetlands Reports

• Fiddler Crab. William L. Roberts
• CCI Develops New Online GIS Resources. Marcia Berman
• Increasing the Probability of Success in the Construction of Marshes in Coastal Virginia. Kirk J. Havens, Lyle M. Varnell,and Bryan D. Watts
• VIMS Shoreline Reports to Be Updated and Go Online.

Semiclassical Theory Of Weighted Spectra For Regular Systems: Absorption Spectra And Decay Rates, M. W. Beims, V. Kondratovich, John B. Delos

Arts & Sciences Articles

We derive a simple semiclassical representation to describe the large-scale structure of the spectrum of regular systems weighted by some arbitrary function W. Examples of weighted spectra are the width-weighted spectrum, which represents the decay rate of an unstable system, and the oscillator-strength-weighted spectrum, which represents the photoabsorption rate. Semiclassical representations of such spectra involve stationary-phase contributions, which are periodic or closed orbits, and end-point contributions, which are loops on an extremal torus. The theory provides the link between semiquantal formulas and the closed-orbit theory of atomic photoabsorption. It also allows calculation of an average decay rate without knowledge …

Classically Forbidden Recurrences In The Photoabsorption Spectrum Of Lithium, V. Kondratovich, John B. Delos, Neal Spellmeyer, Daniel Kleppner

Arts & Sciences Articles

We present data on the photoabsorption spectrum of lithium atoms in an electric field at energies between the saddle point of the Stark potential and below the field-free ionization threshold. The spectrum displays a sequence of sharp resonances and a sequence of broad ones. We find that the broad resonances arise from the classically forbidden reflection of waves above a dynamical potential barrier. The recurrence spectrum is also observed and it is dramatically affected by above-barrier reflections. We have developed a semiclassical theory that interprets the spectra using quasiclassical trajectories that undergo above-barrier reflection.