Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

William & Mary

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 2221 - 2250 of 4602

Full-Text Articles in Physical Sciences and Mathematics

Nearshore Morphology And Lithology: Links To Framework Geology And Shoreline Change, Jennifer L. Miselis Jan 2008

Nearshore Morphology And Lithology: Links To Framework Geology And Shoreline Change, Jennifer L. Miselis

Dissertations, Theses, and Masters Projects

Despite evidence of the geologic and morphologic complexity of inner shelves worldwide, there is a paucity of observations from the nearshore, inhibiting direct comparison of these factors to coastal change. Using geophysical instruments to characterize the geology of the nearshore, this research focuses on the relationships between nearshore stratigraphy, sediment heterogeneity, shoreface morphology and shoreline behavior. While generally not considered in engineering models of shoreline evolution, these factors influence nearshore processes. Overall, the findings presented highlight the importance of nearshore geology, both at the seafloor and underlying it, in contributing to modem sediment transport processes affecting beaches. Shallow, sub-seafloor geology …

Go to article

Bottom-Up And Top-Down Controls On Sedimentary Ecosystem Functioning In A Seagrass Habitat, Amanda C. Spivak Jan 2008

Bottom-Up And Top-Down Controls On Sedimentary Ecosystem Functioning In A Seagrass Habitat, Amanda C. Spivak

Dissertations, Theses, and Masters Projects

Coastal seagrass ecosystems are complex habitats that are increasingly influenced by human perturbations. Disturbances that affect the strength of bottom-up (i.e. resource availability) and top-down (i.e. consumer) controls may also influence biomass distribution between trophic levels, sediment biogeochemistry, and seagrass ecosystem metabolism. Here, I experimentally tested how top-down and bottom-up perturbations interact with community structure (diversity, food chain length of epibenthic consumers) to alter sediment biogeochemistry and ecosystem metabolism in an experimental eelgrass (Zostera marina ) system. My data indicated that resource availability influenced SOM composition and ecosystem metabolism. Light availability tended to be a stronger determinant of SOM composition …

Go to article

Synthesis And Field Emission Properties Of Carbon Nanostructures, Kun Hou Jan 2008

Synthesis And Field Emission Properties Of Carbon Nanostructures, Kun Hou

Dissertations, Theses, and Masters Projects

This dissertation focuses on developing carbon nanostructures for application as the electron emissive material in novel back-gated triode field emission devices. The synthesis, characterization, and field emission properties of carbon nanostructures, including 1-D carbon nanofibers (CNF), 2-D carbon nanosheets (CNS), and chromium oxide coated carbon nanosheets (CrOx-CNS), are presented in this work.;First, we have fabricated aligned carbon nanofiber based back-gated triode field emission devices and confirmed the operation of these devices. 1-D carbon nanofibers were directly synthesized on blank TiW substrates using direct current plasma enhanced chemical vapor deposition. It was found that the morphology of carbon nanofibers could be …

Go to article

Methods For Stabilizing High Reynolds Number Lattice Boltzmann Simulations, Brian Robert Keating Jan 2008

Methods For Stabilizing High Reynolds Number Lattice Boltzmann Simulations, Brian Robert Keating

Dissertations, Theses, and Masters Projects

The Lattice Boltzmann Method (LBM) is a simple and highly efficient method for computing nearly incompressible fluid flow. However, it is well known to suffer from numerical instabilities for low values of the transport coefficients. This dissertation examines a number of methods for increasing the stability of the LBM over a wide range of parameters. First, we consider a simple transformation that renders the standard LB equation implicit. It is found that the stability is largely unchanged. Next, we consider a stabilization method based on introducing a Lyapunov function which is essentially a discrete-time H-function. The uniqueness of an H-function …

Go to article

As Particles Collide: Extra Dimensions And Heavy Leptons, Erin Kathleen De Pree Jan 2008

As Particles Collide: Extra Dimensions And Heavy Leptons, Erin Kathleen De Pree

Dissertations, Theses, and Masters Projects

Despite excellent agreement with experiment, the Standard Model leaves several issues unresolved. These issues will be explored and several extensions to the Standard Model introduced: models with extra dimensions and a fourth family of particles.;In extra dimensional models, there are Fourier modes of the Standard Model particles. We study the detection of bound states of one of the modes and its Standard Model particle.;We then explore a particular model of extra dimensions known as Randall-Sundrum or warped extra dimensions. We will see how this model affects top quark measurements at the proposed International Linear Collider.;Finally we will study the detection …

Go to article

Measurement Of Inclusive Proton Double -Spin Asymmetries And Polarized Structure Functions, Robert G. Fersch Jan 2008

Measurement Of Inclusive Proton Double -Spin Asymmetries And Polarized Structure Functions, Robert G. Fersch

Dissertations, Theses, and Masters Projects

The scattering of polarized electrons from a polarized proton target provides a means for studying the internal spin structure of the proton. The CLAS (CEBAF Large Acceptance Spectrometer) EG1b experiment in Hall-B at Jefferson Laboratory measured double-spin inclusive and exclusive electron-nucleon scattering asymmetries using longitudinally polarized frozen NH3 and ND3 targets and a longitudinally polarized electron beam at 4 different energies (1.6, 2.5, 4.2, 5.6 GeV). Extraction of the virtual photon asymmetry Ap1 (for 0.05 GeV2 < Q2 < 5.0 GeV2) provides precision measurements of the polarized proton spin-structure function gp1 in and above the resonance region. Linear regression of data between the varying energies yields new constraints on the virtual photon asymmetry Ap2 (and thus the structure function gp2 ) in the resonance region (for 0.3 GeV2 < Q2 < 1.0 GeV2). Measurements of these structure functions and their moments allows testing of perturbative Quantum Chromodynamics (pQCD) models and evaluation of moments of the structure functions in the Operator Product Expansion. Testing of Chiral Perturbation Theory (chiPT) at Q2 < 0.2 GeV 2 is enabled by the new data. Other applications of polarized structure functions include measurement of foward-spin polarizability, evaluation of high-order corrections in 1H hyperfine splitting, and testing of quark-hadron duality.

Go to article

Status, Distribution And Reproductive Rates Of American Oystercatchers In Virginia, Alexandra Lee Wilke Jan 2008

Status, Distribution And Reproductive Rates Of American Oystercatchers In Virginia, Alexandra Lee Wilke

Dissertations, Theses, and Masters Projects

No abstract provided.

Go to article

Broad Spatial Trends In Osprey Provisioning, Reproductive Success, And Population Growth Within Lower Chesapeake Bay, Kenneth Andrew Glass Jan 2008

Broad Spatial Trends In Osprey Provisioning, Reproductive Success, And Population Growth Within Lower Chesapeake Bay, Kenneth Andrew Glass

Dissertations, Theses, and Masters Projects

No abstract provided.

Go to article

Mercury Levels In Newly Independent Songbirds, Anne Moire Condon Jan 2008

Mercury Levels In Newly Independent Songbirds, Anne Moire Condon

Dissertations, Theses, and Masters Projects

No abstract provided.

Go to article

Automatically Generating Random Test Data For Relevant And Implicitly Defined Subdomains, John Alexander Murphy Jan 2008

Automatically Generating Random Test Data For Relevant And Implicitly Defined Subdomains, John Alexander Murphy

Dissertations, Theses, and Masters Projects

No abstract provided.

Go to article

Organotitanium-Aluminum Promoted Carbometalations Of Alkynols: Substituent Effects, Nikola A. Nikolic Jan 2008

Organotitanium-Aluminum Promoted Carbometalations Of Alkynols: Substituent Effects, Nikola A. Nikolic

Dissertations, Theses, and Masters Projects

No abstract provided.

Go to article

Time-Resolved Magnetic Flux And Ac-Current Distributions In Superconducting Yttrium Barium Copper Oxide Thin Films And Multifilaments, Ran Yang Jan 2008

Time-Resolved Magnetic Flux And Ac-Current Distributions In Superconducting Yttrium Barium Copper Oxide Thin Films And Multifilaments, Ran Yang

Dissertations, Theses, and Masters Projects

Time-resolved magneto-optical imaging (TRMOI) technique allows dynamic ac transport measurements on superconductors. The high time and spatial resolutions of the measurements also offer good quantitative data analysis of the MO images. YBa2Cu 3O7-delta (YBCO) was discovered as a high-temperature superconductor (HTSC) which has wide applications due to its high critical temperature of Tc = 91 K, and high critical current density Jc in the order of 106-7 Acm-2. Many of the applications require high ac current load and a high magnetic field. We study the interaction behavior of YBCO thin films in an ac transport current and a dc magnetic …

Go to article

Center For Coastal Resources Management Annual Report 2007, Center For Coastal Resources Management Jan 2008

Center For Coastal Resources Management Annual Report 2007, Center For Coastal Resources Management

Reports

No abstract provided.

Go to article

King George, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss Jan 2008

King George, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss

Reports

No abstract provided.

Go to article

Virginia Game Fish Tagging Program Annual Report 2007, John A. Lucy, Lewis Gillingham Jan 2008

Virginia Game Fish Tagging Program Annual Report 2007, John A. Lucy, Lewis Gillingham

Reports

Initiated in 1995, the Virginia Game Fish Tagging Program (VGFTP) database is comprised of tagged fish records, and corresponding recaptured fish records. These records are primarily generated through contributed efforts of a dedicated corps of trained marine anglers targeting only a select number of target species. The recaptured fish records are the result of observant individuals noticing the tags in live or freshly-boxed/shipped fish. Recapture reports originate from a mix of sources, including marine anglers, commercial fishers, workers in fish packinghouses, wholesale and retail sellers of fish, and NOAA Fisheries observers on coastal trawl boats.

Go to article

The Virginia Clean Marina Guidebook, Virginia Clean Marina Program, Virginia Institute Of Marine Science Dec 2007

The Virginia Clean Marina Guidebook, Virginia Clean Marina Program, Virginia Institute Of Marine Science

Reports

No abstract provided.

Go to article

Using Seeds To Propagate And Restore Vallisneria Americana Michaux (Wild Celery) In The Chesapeake Bay, Kenneth A. Moore, Jesse C. Jarvis Dec 2007

Using Seeds To Propagate And Restore Vallisneria Americana Michaux (Wild Celery) In The Chesapeake Bay, Kenneth A. Moore, Jesse C. Jarvis

Reports

Loss of submerged aquatic vegetation (SAV) has been significant in many coastal and estuarine systems such as the Chesapeake Bay where SAV die-offs have been observed in marine, brackish, and freshwater SAV communities (Orth and Moore 1983). Large-scale replanting using whole plants can be cost-prohibitive, and the use of plants taken from wild populations for propagule supply may not be possible or desirable. The use of SAV seeds for restoration has been increasingly demonstrated to be an effective method for replanting large areas of bottom, especially for marine species such as eelgrass, Zostera marina (Pickerell et al. 2005; Orth et …

Go to article

Development Of A Nontidal Wetland Inventory And Monitoring Strategy For Virginia – Completion Of Phase Ii (Coastal Plain And Piedmont Physiographic Provinces), Center For Coastal Resources Management, Virginia Institute Of Marine Science Dec 2007

Development Of A Nontidal Wetland Inventory And Monitoring Strategy For Virginia – Completion Of Phase Ii (Coastal Plain And Piedmont Physiographic Provinces), Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

No abstract provided.

Go to article

Performance Of Sills: St. Mary’S City, St. Mary’S River, Maryland, C. Scott Hardaway Jr., W. G. Reay, Jian Shen, Scott Lerberg, Donna A. Milligan, Christine A. Wilcox, Kevin P. O'Brien Dec 2007

Performance Of Sills: St. Mary’S City, St. Mary’S River, Maryland, C. Scott Hardaway Jr., W. G. Reay, Jian Shen, Scott Lerberg, Donna A. Milligan, Christine A. Wilcox, Kevin P. O'Brien

Reports

Living shorelines represent a shoreline management option that combines various erosion control methodologies and/or structures while at the same time restoring or preserving natural shoreline vegetation communities. A common living shoreline design in Chesapeake Bay includes a low offshore rock sill to absorb wave energy with an emergent wetland landward of the sill to enhance erosion control, provide critical habitat, and improve water quality condition. This study is part of a larger, ongoing project to (1) evaluate erosion control effectiveness and the sustainability of offshore sill and fringing marsh design and structure, (2) evaluate ecological services (e.g., habitat value, water …

Go to article

Evaluation Of Striped Bass Stocks In Virginia : Monitoring And Tagging Studies, 2004-2008 - Annual Report 1 September 2006 - 31 August 2007, Philip W. Sadler, John M. Hoenig, Robert E. Harris, Rebecca J. Wilk, Lydia M. Goins Nov 2007

Evaluation Of Striped Bass Stocks In Virginia : Monitoring And Tagging Studies, 2004-2008 - Annual Report 1 September 2006 - 31 August 2007, Philip W. Sadler, John M. Hoenig, Robert E. Harris, Rebecca J. Wilk, Lydia M. Goins

Reports

This report presents the results of striped bass (Morone saxatilis) tagging and monitoring activities in Virginia during the period 1 September 2006 through 31 August 2007. It includes an assessment of the biological characteristics of striped bass taken from the 2007 spring spawning run, estimates of annual survival and fishing mortality based on annual spring tagging, and the preliminary results of the fall 2006 study that documents the prevalence of mycobacterial infections of striped bass in Chesapeake Bay. The information contained in this report is required by the Atlantic States Marine Fisheries Commission and is used to implement a coordinated …

Go to article

Tidal Flushing Characteristics In Virginia’S Tidal Embayments, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Julie Herman, Jian Shen, Jie Huang Nov 2007

Tidal Flushing Characteristics In Virginia’S Tidal Embayments, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Julie Herman, Jian Shen, Jie Huang

Reports

This project evaluated water bodies in the Virginia coastal zone using several water quality models to calculate residence times. Results were grouped into tidal flushing categories (quickly, intermediately, and slowly flushed) that reflect a relative time frame in which a water body is flushed.

Go to article

Hydrogen-Bonding Networks In Heterocyclic Thioureas, Aakarsh Saxena, Robert D. Pike Nov 2007

Hydrogen-Bonding Networks In Heterocyclic Thioureas, Aakarsh Saxena, Robert D. Pike

Arts & Sciences Articles

The synthesis of heterocyclic thioureas from heterocyclic amines with phenyl- or methylisothiocyanate or CS2 is described. Seven new X-ray crystal structures are reported: In N-(3-pyridyl)-N′-phenylthiourea (Pna21, a = 10.1453(3), b = 17.6183(5), c = 6.4787(2), V = 1158.02(6), Z = 4) hydrogen-bonding results in formation of a 3D network consisting of helices, which form channels parallel to the c-axis. In N-(4-pyridyl)-N′-phenylthiourea (P21/c, a = 16.9314(3), b = 10.3554(2), c = 13.5152(3), β = 106.5080(10), V = 2271.96(8), Z = 4, two independent molecules) hydrogen-bonding results in N–H···S bridged dimers …

Go to article

Shellfish Aquaculture Vulnerability Model, Center For Coastal Resources Management, Virginia Institute Of Marine Science Nov 2007

Shellfish Aquaculture Vulnerability Model, Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

No abstract provided.

Go to article

Coastal Maritime Forests In Virginia – Delineation And Distribution, Marcia Berman, Harry Berquist Nov 2007

Coastal Maritime Forests In Virginia – Delineation And Distribution, Marcia Berman, Harry Berquist

Reports

This project had two major goals. The first builds on an earlier effort by the Virginia Department of Forestry, who delineated maritime forests using remote sensing techniques. Their project integrated land use and soils data to generate a map that defines potential boundaries of maritime forest. This study follows an identical approach with two major exceptions. The first is the soils data used in this study is mapped at a much finer scale. The second is this study has a field validation component that reviewed random sites around selected locations to ground-truth the remote sensing output. The Virginia Department of …

Go to article

Virginia Wetlands Report Vol. 22, No. 2, Virginia Institute Of Marine Science, Center For Coastal Resources Management Oct 2007

Virginia Wetlands Report Vol. 22, No. 2, Virginia Institute Of Marine Science, Center For Coastal Resources Management

Virginia Wetlands Reports

The Big Picture: Managing Wetland from a Shoreline Perspective

Go to article

Evaluating Recruitment Of American Eel, Anguilla Rostrata, To The Potomac River (Spring 2007), Hank Brooks, Wendy A. Lowery, Aimee Halvorson, James Gartland, Marcel M. Montane Sep 2007

Evaluating Recruitment Of American Eel, Anguilla Rostrata, To The Potomac River (Spring 2007), Hank Brooks, Wendy A. Lowery, Aimee Halvorson, James Gartland, Marcel M. Montane

Reports

Harvests of American eel along the U.S. Atlantic Coast have declined in recent years, and similar patterns have been noted in the Canadian Maritime Provinces as well as in Europe with its congener, A. anguilla (Ciccotti et al., 4 1995). Fishery independent indices of abundance have also shown a decline in American eel populations in recent years (Richkus and Whalen, 1999; Geer, 2003; Montane and Fabrizio, 2006). Possible explanations for this decline include Gulf Stream shifts, pollution, overfishing, parasites, and barriers to fish passage (Castonguay et al., 1994; Haro et al., 2000). In addition, local factors such as unfavorable wind-driven …

Go to article

The Coastal Primary Sand Dune And Beach Act, Lyle M. Varnell, C. Scott Hardaway Jr. Sep 2007

The Coastal Primary Sand Dune And Beach Act, Lyle M. Varnell, C. Scott Hardaway Jr.

Reports

This document presents the supporting information and justification for the following recommendations: • Adding Middlesex County and Westmoreland County to the list of localities authorized to adopt the model ordinance of the Coastal Primary Sand Dune and Beach Act (Title 28.2, Chapter 14 of the Virginia Code) would result in the inclusion of significant dune resources into Virginia’s tidal shoreline management program. • Adding the localities of Charles City, Essex, Gloucester, Isle of Wight, James City, King and Queen, King George, Middlesex, New Kent, Newport News, Prince George, Richmond (county), Stafford, Surry, Westmoreland, and York to the list of localities …

Go to article

Gis Data: Lynnhaven River Virginia Beach, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, Karen Reay, David Weiss Aug 2007

Gis Data: Lynnhaven River Virginia Beach, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, Karen Reay, David Weiss

Data

The data contained within the Shoreline Inventory is based on a three-tiered shoreline assessment approach. The assessment characterizes conditions that are observed from a small boat navigating along the shoreline. Hand-held GPS units are used to log features. The three tiered shoreline assessment approach reports conditions in three regions: 1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, stability, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. Three GIS coverages are generated. The lynn_lubc coverage contains features related to the land use …

Go to article

Lynnhaven River Virginia Beach, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, Karen Reay, David Weiss Aug 2007

Lynnhaven River Virginia Beach, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, Karen Reay, David Weiss

Reports

The data contained within the Shoreline Inventory is based on a three-tiered shoreline assessment approach. The assessment characterizes conditions that are observed from a small boat navigating along the shoreline. Hand-held GPS units are used to log features. The three tiered shoreline assessment approach reports conditions in three regions: 1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, stability, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. Three GIS coverages are generated. The lynn_lubc coverage contains features related to the land use …

Go to article

Estimating Relative Abundance Of Young-Of-The-Year American Eel Anguilla Rostrata In The Virginia Tributaries Of Chesapeake Bay (Spring 2006), Marcel M. Montane, Wendy A. Lowery, Hank Brooks, Aimee D. Halvorson Aug 2007

Estimating Relative Abundance Of Young-Of-The-Year American Eel Anguilla Rostrata In The Virginia Tributaries Of Chesapeake Bay (Spring 2006), Marcel M. Montane, Wendy A. Lowery, Hank Brooks, Aimee D. Halvorson

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (hereafter referred to as FMP) for the American eel in November 1999. The FMP focuses on increasing coastal states’ efforts to collect American eel data through both fishery dependent and fishery independent studies. Consequently, member jurisdictions (including Virginia) agreed to implement an annual survey for YOY American eels. The survey is intended to “…characterize trends in annual recruitment of the YOY eels over time [to produce a] qualitative appraisal of the annual recruitment of American eel to the U.S. Atlantic Coast” (ASMFC, 2000). The development of these …

Go to article

First Prev Next Last