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Full-Text Articles in Physical Sciences and Mathematics

The Roles Of Dispersal And Predation In Determining The Seedling Recruitment Patterns Of A Zostera Marina System, Stephen R. Manley Jan 2014

The Roles Of Dispersal And Predation In Determining The Seedling Recruitment Patterns Of A Zostera Marina System, Stephen R. Manley

Dissertations, Theses, and Masters Projects

Seed dispersal and seed predation are two important processes in the early life history of plants. The interaction between these two processes influences the population recruitment from a parent plant. These mechanisms have been studied extensively in terrestrial plants and have resulted in various models to describe plant recruitment (e.g. Janzen-Connell, Hubbell, McCanny). However, seed dispersal and predation may also influence the population recruitment of marine angiosperms, such as Zostera marina (eelgrass). The objectives of this study were to determine: 1.) the patterns of seed dispersal as a function of distance from the seed source, 2.) the predation pressure on …


The Effects Of Medium On The Uv-Induced Photodegradation Of Rhodamine B Dye, Carolyn Louise Carta Jan 2014

The Effects Of Medium On The Uv-Induced Photodegradation Of Rhodamine B Dye, Carolyn Louise Carta

Dissertations, Theses, and Masters Projects

No abstract provided.


Studies Of Mortality Estimation, Amy Y. Then Jan 2014

Studies Of Mortality Estimation, Amy Y. Then

Dissertations, Theses, and Masters Projects

Instantaneous total mortality rate Z can be partitioned into two components: fishing, F, and natural mortality, M. A number of data-poor methods have been developed to estimate Z, F, and M, and these methods tend to rely on fairly restrictive assumptions as well as on data types that are easy to obtain, e.g., length or other life history information. The overarching goal of this dissertation is to contribute to the advancement of methods for estimating these important and influential stock parameters. The relevant issues and the gaps in knowledge pertaining to these data-poor methods are outlined in the Introduction chapter …


Anthropogenic Modifications Of Connectivity At The Aquatic-Terrestrial Ecotone In The Chesapeake Bay, Robert Earl Isdell Jan 2014

Anthropogenic Modifications Of Connectivity At The Aquatic-Terrestrial Ecotone In The Chesapeake Bay, Robert Earl Isdell

Dissertations, Theses, and Masters Projects

No abstract provided.


Development Of A Large-Scale Storm Surge And High-Resolution Sub-Grid Inundation Model For Coastal Flooding Applications: A Case Study During Hurricane Sandy, Jon Derek Loftis Jan 2014

Development Of A Large-Scale Storm Surge And High-Resolution Sub-Grid Inundation Model For Coastal Flooding Applications: A Case Study During Hurricane Sandy, Jon Derek Loftis

Dissertations, Theses, and Masters Projects

Coastal inundation initiated via storm surge by hurricanes and nor'easters along the U.S. East Coast is a substantial threat to residential properties, community infrastructure, and human life. During and after the storm, compounding with heavy precipitation and upland drainage, inundation can be caused by the combination of storm surge and river-induced inland flooding in various locations throughout the coastal plain. Thus, coastal inundation can be expanded from the open coast upstream into the tributaries of the New York Bay including the Hudson and East River systems. Given the cross-disciplinary nature of the dynamics (encompassing hydraulics, oceanography, and hydrology), and the …


Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski Jan 2014

Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski

Dissertations, Theses, and Masters Projects

The value of habitats in terms of biological production is of interest to ecologists and resource managers. Seagrasses are a commonly occurring habitat type in shallow marine waters and have been shown to support high abundances of fish and invertebrates. In lower Chesapeake Bay, seagrasses grow in a shallow fringe in the subtidal zone. Although, ample evidence exists for the value of these habitats as foraging and rearing areas for a variety of organisms, the connectivity among species and the benefits derived from these habitats in terms of production have not been well described, especially for small, seasonally occurring finfishes. …


Factors Influencing Year-Class Strength And Growth Of Young-Of-The-Year Summer Flounder (Paralichthyidae: Paralichthys Dentatus), Lauren N. Nys Jan 2014

Factors Influencing Year-Class Strength And Growth Of Young-Of-The-Year Summer Flounder (Paralichthyidae: Paralichthys Dentatus), Lauren N. Nys

Dissertations, Theses, and Masters Projects

No abstract provided.


High-Resolution Sediment Records Of Seismicity And Seasonal Sedimentation From Prince William Sound, Alaska, Using Xrf Core Scanning, Eric J. Miller Jan 2014

High-Resolution Sediment Records Of Seismicity And Seasonal Sedimentation From Prince William Sound, Alaska, Using Xrf Core Scanning, Eric J. Miller

Dissertations, Theses, and Masters Projects

The southern coast of Alaska is a climatically sensitive and tectonically active region, however due to its remoteness and harsh climate there are limited long-term historical records of environmental conditions such as storm frequency, river discharge, and earthquakes. In order to determine the potential for Prince William Sound sediments to contain high-resolution paleorecords of these conditions, a suite of 11 gravity cores was collected within the Sound in order to determine the modern day sediment depositional trends and to develop elemental proxies for earthquakes and seasonal sedimentation. 210Pb/137Cs-derived sedimentation rates and grain size trends indicate that there are two distinct …


Towards Secure, Power-Efficient And Location-Aware Mobile Computing, Hao Han Jan 2014

Towards Secure, Power-Efficient And Location-Aware Mobile Computing, Hao Han

Dissertations, Theses, and Masters Projects

In the post-PC era, mobile devices will replace desktops and become the main personal computer for many people. People rely on mobile devices such as smartphones and tablets for everything in their daily lives. A common requirement for mobile computing is wireless communication. It allows mobile devices to fetch remote resources easily. Unfortunately, the increasing demand of the mobility brings many new wireless management challenges such as security, energy-saving and location-awareness. These challenges have already impeded the advancement of mobile systems. In this dissertation we attempt to discover the guidelines of how to mitigate these problems through three general communication …


Sediment Deposition And Reworking: A Modeling Study Using Isotopically Tagged Sediment Classes, Justin J. Birchler Jan 2014

Sediment Deposition And Reworking: A Modeling Study Using Isotopically Tagged Sediment Classes, Justin J. Birchler

Dissertations, Theses, and Masters Projects

A sediment transport model within the Regional Ocean Modeling System (ROMS) was used to examine how repeated cycles of deposition, erosion, and bioturbation influence flood and storm event bed character offshore of a significant fluvial source. Short-lived radioisotopes Beryllium-7 (7Be) and Thorium-234 (234Th) can be used as tracers of deposition and reworking on the continental shelf, and modeled profiles of these radioisotopes, along with simulated profiles of sediment bed grain size distributions, were analyzed for various model runs.The presence of an atmospherically derived radionuclide,7Be, in seafloor sedimentindicates terrestrial (riverine derived) sediment deposition offshore of a fluvial source.In contrast,234Th naturally occurs …


Effects Of Sub Lethal Methylmercury Exposure On Pigment Coloration In A Model Songbird, Jessica Lynn Spickler Jan 2014

Effects Of Sub Lethal Methylmercury Exposure On Pigment Coloration In A Model Songbird, Jessica Lynn Spickler

Dissertations, Theses, and Masters Projects

No abstract provided.


Magneto-Optics And Magneto-Transport Studies On Thin Films For Sensor Applications, Kaida Yang Jan 2014

Magneto-Optics And Magneto-Transport Studies On Thin Films For Sensor Applications, Kaida Yang

Dissertations, Theses, and Masters Projects

Recent progress and interest have bought considerable effort to bear on the synthesis and opportunities of magnetic thin films in different fields. There are applications in many fields, including remote sensing, waveguide applications, hard drive applications, etc. at the College of William and Mary, we have focused on utilizing magnetic thin films in some of these applications and are deeply involved in the optimization process of the thin films.


A Biogeochemical Data Assimilative Modeling Study In The Mid-Atlantic Bight, Yongjin Xiao Jan 2014

A Biogeochemical Data Assimilative Modeling Study In The Mid-Atlantic Bight, Yongjin Xiao

Dissertations, Theses, and Masters Projects

Continental shelves are generally believed to play a critical role in ocean biogeochemical cycling, however this has raised the question as to the relative importance of various nitrogen flux terms such as denitrification, burial, net community production and advective fluxes. Quantifying these fluxes on an annual area-integrated basis using traditional observational means is often difficult, due to the fact that these fluxes rapidly change on relatively small spatial scales, making inadequate data resolution a significant problem. Satellite remote sensing data and numerical modeling provide alternative ways to fill the data gaps, and hence have the potential to generate quantitative estimates …


Using A Sonic Net To Deter Pest Bird Species: Excluding European Starlings From Food Sources By Disrupting Their Acoustic Environment, Ghazi Mahjoub Jan 2014

Using A Sonic Net To Deter Pest Bird Species: Excluding European Starlings From Food Sources By Disrupting Their Acoustic Environment, Ghazi Mahjoub

Dissertations, Theses, and Masters Projects

No abstract provided.


Superconducting Thin Films For Srf Cavity Applications: A Route To Higher Field Gradient Linacs, Wiliam Michael Roach Jan 2014

Superconducting Thin Films For Srf Cavity Applications: A Route To Higher Field Gradient Linacs, Wiliam Michael Roach

Dissertations, Theses, and Masters Projects

Many linear accelerator (linac) applications rely on the use of superconducting radio frequency (SRF) cavities. In order to overcome the current field gradient limits imposed by the use of bulk niobium, a model involving the deposition of alternating superconducting-insulating-superconducting (SIS) thin films onto the interior surface of SRF cavities has been proposed. Since SRF performance is a surface phenomenon, the critical surface of these cavities is less than 1 micron thick, thus enabling the use of thin films. Before such approach can successfully be implemented fundamental studies correlating the microstructure and superconducting properties of thin films are needed. to this …


Effective Resource And Workload Management In Data Centers, Lei Lu Jan 2014

Effective Resource And Workload Management In Data Centers, Lei Lu

Dissertations, Theses, and Masters Projects

The increasing demand for storage, computation, and business continuity has driven the growth of data centers. Managing data centers efficiently is a difficult task because of the wide variety of datacenter applications, their ever-changing intensities, and the fact that application performance targets may differ widely. Server virtualization has been a game-changing technology for IT, providing the possibility to support multiple virtual machines (VMs) simultaneously. This dissertation focuses on how virtualization technologies can be utilized to develop new tools for maintaining high resource utilization, for achieving high application performance, and for reducing the cost of data center management.;For multi-tiered applications, bursty …


Effects Of Saltwater Intrusion On Vegetation Dynamics And Nutrient Pools In Low-Salinity Tidal Marshes, Pamunkey River (Virginia, Usa), Lori A. Sutter Jan 2014

Effects Of Saltwater Intrusion On Vegetation Dynamics And Nutrient Pools In Low-Salinity Tidal Marshes, Pamunkey River (Virginia, Usa), Lori A. Sutter

Dissertations, Theses, and Masters Projects

This study investigated vegetation changes in a former tidal freshwater marsh (TFM) to determine the role that salinity intrusion plays in vegetation dynamics. Field observations along a narrow salinity gradient in the Pamunkey River revealed that vegetation is shifting to fewer dominants with increasing salinity. Two remaining dominants, Peltandra virginica and Zizania aquatica (hereafter Peltandra and Zizania, respectively), had variable net CO2 assimilation throughout the growing season. Peltandra net CO2 assimilation declined both over the growing season and in marshes with higher salinity; whereas, Zizania generally increased over the growing season peaking in late summer. The same species' tissue nutrients …


Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker Jan 2014

Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker

Dissertations, Theses, and Masters Projects

White Marlin (Kajikia albida) is a highly migratory species that occurs throughout temperate and tropical regions of the Atlantic Ocean and is the basis of a large sport fishery along the United States Atlantic coast. The single, Atlantic-wide stock is considered to be overfished, with less than one-third the spawning biomass estimated to be necessary for maximum sustainable yield. Billfish management measures adopted by the International Commission for the Conservation of Atlantic Tunas (ICCAT) and implemented in the U.S. by the National Marine Fisheries Service (NMFS), as well as increasing angler awareness of conservation, have resulted in the vast majority …


Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber Jan 2014

Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber

Dissertations, Theses, and Masters Projects

Copepods are the dominant mesozooplankton in the Southern Ocean, but long- term change in their abundance and distribution along the Western Antarctic Peninsula (WAP), a region experiencing rapid climate warming, is unknown. Copepods are also potentially important grazers of phytoplankton in the WAP and contributors to carbon export through production of sinking fecal pellets. I examined summer (January- February) copepod community structure and abundance along the WAP over two decades (1993-2013) and investigated long-term trends in copepod abundance and their relationship with environmental parameters (sea ice, phytoplankton biomass and productivity, climate indices, and sea surface temperature). Copepods comprised on average …


An Evaluation Of A Reduced Bar Spacing Turtle Excluder Device In The U.S Gulf Of Mexico Offshore Shrimp Trawl Fishery, Michel Anthony Nalovic Jan 2014

An Evaluation Of A Reduced Bar Spacing Turtle Excluder Device In The U.S Gulf Of Mexico Offshore Shrimp Trawl Fishery, Michel Anthony Nalovic

Dissertations, Theses, and Masters Projects

Shrimp are the most economically valuable internationally-traded seafood commodity, and wild-caught, trawled shrimp make up almost half of the ~6.6 million metric tons of annual global production. Shrimp trawling is responsible for one-third of the world’s total fisheries bycatch, leading many to consider shrimp trawling to be the single most destructive fishing practice in the world. Though the bycatch of large marine animals can be significantly reduced by use of turtle excluder devices (TEDs) on shrimp trawls, current TED designs are ineffective at reducing the capture of smaller organisms which represent a large portion of the total bycatch. To further …


Nonlinear Optical Studies Of Photoelastic Effect And Magneto-Plasmonics, Wei Zheng Jan 2014

Nonlinear Optical Studies Of Photoelastic Effect And Magneto-Plasmonics, Wei Zheng

Dissertations, Theses, and Masters Projects

Nonlinear optical (NLO) processes are optical phenomena involving a nonlinear response to an applied light field. Two kinds of nonlinearities are studied in this dissertation: magnetic-induced second-harmonic generation (MSHG) interacting with surface plasmon, called "nonlinear magnetoplasmonics" (NMP), and the nonlinear index induced by a strong pump beam in Titanium doped sapphire crystal, referred to as population-induced nonlinear index effect.;The fundamentals of the major effects involved are discussed, which include: surface plasmon and its field enhancement effect, MSHG technique and phenomenological calculations, the contrast ratio of magnetic switching, the calculation of lensing effects, population induced strain, and photoelastic effect. Furthermore, the …


Enhancement Of Ms Signal Processing For Improved Cancer Biomarker Discovery, Qian Si Jan 2014

Enhancement Of Ms Signal Processing For Improved Cancer Biomarker Discovery, Qian Si

Dissertations, Theses, and Masters Projects

Technological advances in proteomics have shown great potential in detecting cancer at the earliest stages. One way is to use the time of flight mass spectroscopy to identify biomarkers, or early disease indicators related to the cancer. Pattern analysis of time of flight mass spectra data from blood and tissue samples gives great hope for the identification of potential biomarkers among the complex mixture of biological and chemical samples for the early cancer detection. One of the keys issues is the pre-processing of raw mass spectra data. A lot of challenges need to be addressed: unknown noise character associated with …


Sediment And Organic Carbon Burial In Englebright Lake, Ca Over The Last Century, Christina Rose Pondell Jan 2014

Sediment And Organic Carbon Burial In Englebright Lake, Ca Over The Last Century, Christina Rose Pondell

Dissertations, Theses, and Masters Projects

The proliferation of dams has impacted over 67% of the world's largest rivers, degrading ecosystems, severing river-watershed connectivity, and reducing water, sediment, and carbon supply from rivers to the coastal ocean by 20 to 100%. Many studies have focused on the downstream impacts of dams, but few have quantified the amounts and quality of organic matter stored within impoundments. This study examined organic carbon (OC) sources and accumulation in a reservoir in northern California to characterize the organic matter retained in terrestrial systems by these man-made structures and relate the amounts and quality of OC to mining, damming and flood …


Matching Non-Uniformity For Program Optimizations On Heterogeneous Many-Core Systems, Bo Wu Jan 2014

Matching Non-Uniformity For Program Optimizations On Heterogeneous Many-Core Systems, Bo Wu

Dissertations, Theses, and Masters Projects

As computing enters an era of heterogeneity and massive parallelism, it exhibits a distinct feature: the deepening non-uniform relations among the computing elements in both hardware and software. Besides traditional non-uniform memory accesses, much deeper non-uniformity shows in a processor, runtime, and application, exemplified by the asymmetric cache sharing, memory coalescing, and thread divergences on multicore and many-core processors. Being oblivious to the non-uniformity, current applications fail to tap into the full potential of modern computing devices.;My research presents a systematic exploration into the emerging property. It examines the existence of such a property in modern computing, its influence on …


Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney Jan 2014

Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney

Dissertations, Theses, and Masters Projects

No abstract provided.


Exploring A Novel Approach To Technical Nuclear Forensics Utilizing Atomic Force Microscopy, Richard Scot Peeke Jan 2014

Exploring A Novel Approach To Technical Nuclear Forensics Utilizing Atomic Force Microscopy, Richard Scot Peeke

Dissertations, Theses, and Masters Projects

No abstract provided.


Studying And Enabling Reuse In Android Mobile Apps, Andrew Steven Holtzhauer Jan 2014

Studying And Enabling Reuse In Android Mobile Apps, Andrew Steven Holtzhauer

Dissertations, Theses, and Masters Projects

No abstract provided.


Amine- And Sulfide-Sensing Copper(I) Iodide Films And The Structure, Dynamics, And Photophysics In The Copper(I) Iodide-Tetrahydrothiophene System, Kylie Marie Henline Jan 2014

Amine- And Sulfide-Sensing Copper(I) Iodide Films And The Structure, Dynamics, And Photophysics In The Copper(I) Iodide-Tetrahydrothiophene System, Kylie Marie Henline

Dissertations, Theses, and Masters Projects

No abstract provided.


Quantification Of Nursery Habitats For Blue Crabs In Chesapeake Bay, Gina M. Ralph Jan 2014

Quantification Of Nursery Habitats For Blue Crabs In Chesapeake Bay, Gina M. Ralph

Dissertations, Theses, and Masters Projects

The blue crab is an iconic species in Chesapeake Bay, supporting important commercial and recreational fisheries and functioning as a critical link in the food web. Structurally complex habitats are often cited as nurseries for the blue crab, and other commercially important fish and crustacean species, by providing enhanced growth and survival for juveniles. I quantified the value of shallow habitats as nurseries for blue crabs through field studies and a demographic model. In Chapter 2, I utilized a two-year juvenile survey in vegetated habitats of the lower Bay to examine the effect of habitat complexity on the density of …


Exploiting Behavioral Biometrics For User Security Enhancements, Nan Zheng Jan 2014

Exploiting Behavioral Biometrics For User Security Enhancements, Nan Zheng

Dissertations, Theses, and Masters Projects

As online business has been very popular in the past decade, the tasks of providing user authentication and verification have become more important than before to protect user sensitive information from malicious hands. The most common approach to user authentication and verification is the use of password. However, the dilemma users facing in traditional passwords becomes more and more evident: users tend to choose easy-to-remember passwords, which are often weak passwords that are easy to crack. Meanwhile, behavioral biometrics have promising potentials in meeting both security and usability demands, since they authenticate users by "who you are", instead of "what …