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Full-Text Articles in Physical Sciences and Mathematics

Gis Data: Talbot County, Maryland - Shoreline Inventory Data 2020, Karinna Nunez, Marcia Berman, Sharon Killeen, Jessica Hendricks, Tamia Rudnicky, Catherine Riscassi Jan 2021

Gis Data: Talbot County, Maryland - Shoreline Inventory Data 2020, Karinna Nunez, Marcia Berman, Sharon Killeen, Jessica Hendricks, Tamia Rudnicky, Catherine Riscassi

Data

The shoreline inventory files have been generated to support the application of the Maryland Shoreline Stabilization Model (SSM), developed by the Center for Coastal Resources Management (CCRM), Virginia Institute of Marine Science (VIMS), to enhance and streamline regulatory decision making in Maryland. This shoreline inventory includes the features needed as inputs to run the SSM.

The data developed for the Shoreline Inventory is based on a three-tiered shoreline assessment approach. This assessment characterizes conditions by using observations made remotely at the desktop using high resolution imagery. The three-tiered shoreline assessment approach divides the shorezone into three regions:

1) the immediate …


Vims Hydrofile: Ambient Water Monitoring And Meteorological Data For Chesapeake Bay And Near Coastal Shelf Waters, 1942-1982, Gary F. Anderson Jan 2021

Vims Hydrofile: Ambient Water Monitoring And Meteorological Data For Chesapeake Bay And Near Coastal Shelf Waters, 1942-1982, Gary F. Anderson

Data

Historical ambient water quality and meteorologic conditions from cruises conducted by the Virginia Institute of Marine Science in Chesapeake Bay and nearshore coastal shelf waters over a 40-year period through 1982.

Bulk water parameters were routinely measured during cruises conducted in Chesapeake Bay and nearshore coastal waters conducted by VIMS over four decades. Data were punched on 80-character cards known as ‘Form 1’ format by the VIMS central Computer Center. These were later converted to digital files. For this publication the Form 1 files were unpacked into yearly flat files containing two record types:

Station records - Contain surface observations …


Supporting Data: Controls On Sediment Bed Erodibility In A Muddy, Partially-Mixed Tidal Estuary, York River, Virginia, Cristin L. Wright, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs Jan 2021

Supporting Data: Controls On Sediment Bed Erodibility In A Muddy, Partially-Mixed Tidal Estuary, York River, Virginia, Cristin L. Wright, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs

Data

Dataset consists of all sampling cruises with data that were analyzed and used in the statistical modeling associated with Wright (2021) and Wright et al. (2022). Each cruise folder includes erodibility data that was analyzed using a Gust Microcosm along with sediment and water column characteristics.


Center For Coastal Resources Management Annual Report 2020, Center For Coastal Resources Management Jan 2021

Center For Coastal Resources Management Annual Report 2020, Center For Coastal Resources Management

Reports

No abstract provided.


Excited J-- Resonances In Meson-Meson Scattering From Lattice Qcd, Christopher Johnson Jan 2021

Excited J-- Resonances In Meson-Meson Scattering From Lattice Qcd, Christopher Johnson

Dissertations, Theses, and Masters Projects

Understanding the excited light meson spectrum is vital to our understanding of how quarks and gluons bind to become hadrons. This sector is home to a plethora of states including hadrons laying outside the quark model. Distinguishing the from the rest of the spectrum would be made easier if we first had a handle on the light quark anti-quark spectrum. I present the first determination of excited light JPC=1--,2--,3-- resonances in meson-meson scattering at the SU(3) flavor point from lattice QCD. This system can be described in the context of pseudoscalar-vector elastic scattering and I determine two 1-- resonances; a …


Quantifying The Increased Resiliency Of Chesapeake Bay Hypoxia To Environmental Conditions: A Benefit Of Nutrient Reductions, Luke Thomas Frankel Jan 2021

Quantifying The Increased Resiliency Of Chesapeake Bay Hypoxia To Environmental Conditions: A Benefit Of Nutrient Reductions, Luke Thomas Frankel

Dissertations, Theses, and Masters Projects

Seasonal hypoxia is a characteristic feature of the Chesapeake Bay as a result of anthropogenic eutrophication from agriculture and urban development throughout the watershed. Although in recent years coordinated management efforts have successfully reduced the flux of nutrients into the Bay, the overall goal of sufficient oxygen concentrations below the pycnocline for living resources remains unfulfilled. This was particularly apparent in 2018 and 2019 when the volume of hypoxic water exceeded the long-term (35-year) average due to anomalously high riverine discharge. To quantify the impact of watershed nutrient reductions, conventional statistical methods were employed in concert with a 3-D numerical …


Sediment And Terrestrial Organic Carbon Budgets For The Offshore Ayeyarwady Delta: Establishing A Baseline For Future Change, Evan Rose Flynn Jan 2021

Sediment And Terrestrial Organic Carbon Budgets For The Offshore Ayeyarwady Delta: Establishing A Baseline For Future Change, Evan Rose Flynn

Dissertations, Theses, and Masters Projects

Large river deltas serve as globally important archives of terrestrial and shallow marine biogeochemical signatures because of rapid sediment burial, and have the potential to impact global biogeochemical cycling on modern and geologic timescales. This study investigates modern sediment and terrestrial organic carbon (TerrOC) accumulation within the offshore Ayeyarwady Delta in order to determine sediment and TerrOC budgets for this largely understudied mega-delta. The Ayeyarwady is the world’s third largest delta in terms of sediment supply, and remains one of the last long free-flowing rivers in Asia. However, recent increases in regional anthropogenic impacts risk severe alterations to sediment and …


Gis Data: Anne Arundel County, Maryland - Shoreline Inventory Data 2020, Karinna Nunez, Marcia Berman, Sharon Killeen, Jessica Hendricks, Tamia Rudnicky, Catherine Riscassi Jan 2021

Gis Data: Anne Arundel County, Maryland - Shoreline Inventory Data 2020, Karinna Nunez, Marcia Berman, Sharon Killeen, Jessica Hendricks, Tamia Rudnicky, Catherine Riscassi

Data

The shoreline inventory files have been generated to support the application of the Maryland Shoreline Stabilization Model (SSM), developed by the Center for Coastal Resources Management (CCRM), Virginia Institute of Marine Science (VIMS), to enhance and streamline regulatory decision making in Maryland. This shoreline inventory includes the features needed as inputs to run the SSM.

The data developed for the Shoreline Inventory is based on a three-tiered shoreline assessment approach. This assessment characterizes conditions by using observations made remotely at the desktop using high resolution imagery. The three-tiered shoreline assessment approach divides the shorezone into three regions:

1) the immediate …


Rethinking Cache Hierarchy And Interconnect Design For Next-Generation Gpus, Mohamed Assem Abd Elmohsen Ibrahim Jan 2021

Rethinking Cache Hierarchy And Interconnect Design For Next-Generation Gpus, Mohamed Assem Abd Elmohsen Ibrahim

Dissertations, Theses, and Masters Projects

To match the increasing computational demands of GPGPU applications and to improve peak compute throughput, the core counts in GPUs have been increasing with every generation. However, the famous memory wall is a major performance determinant in GPUs. In other words, in most cases, peak throughput in GPUs is ultimately dictated by memory bandwidth. Therefore, to serve the memory demands of thousands of concurrently executing threads, GPUs are equipped with several sources of bandwidth such as on-chip private/shared caching resources and off-chip high bandwidth memories. However, the existing sources of bandwidth are often not sufficient for achieving optimal GPU performance. …


Distributed Byzantine Tolerant Machine Learning, Qi Xia Jan 2021

Distributed Byzantine Tolerant Machine Learning, Qi Xia

Dissertations, Theses, and Masters Projects

Oftentimes, training a large-scale deep learning neural network on a single machine becomes more difficult in a complex network model. Distributed training provides an efficient solution, but opens up participating workers to Byzantine attacks. This problem emerges when some workers cheat during uploading gradients or weights to the central server, e.g., the information received by the server is not always the true result computed by workers. In order to address this problem, we investigate Byzantine problems in distributed machine learning and respectively defend against these kinds of attacks in three scenarios: i) classic distributed machine learning; ii) federated learning; and …


Evaluating The Use Of Acoustic Warning Signals To Reduce Avian Collision Risk, Robin Grace Thady Jan 2021

Evaluating The Use Of Acoustic Warning Signals To Reduce Avian Collision Risk, Robin Grace Thady

Dissertations, Theses, and Masters Projects

Collisions with human-made structures are responsible for billions of bird deaths each year, resulting in ecological damage as well as regulatory and financial burdens to many industries. Acoustic warning signals can alert birds to obstacles in their flight paths in order to mitigate collisions, but these signals should be tailored to the sensory ecology of birds in flight. The effectiveness of various acoustic warning signals likely depends on the influence of background noise and the relative ability of various sound types to propagate within a landscape. I evaluated the ability of four sound signals to elicit collision-avoidant flight behaviors from …


Controls On Estuarine Sediment Bed Erodibility: Insights From The York River Estuary, Cristin Lee Wright Jan 2021

Controls On Estuarine Sediment Bed Erodibility: Insights From The York River Estuary, Cristin Lee Wright

Dissertations, Theses, and Masters Projects

The erodibility of estuarine sediment beds has a number of ecological and societal implications, including alteration of benthic habitats, light-limitation of primary production, and reintroduction of pollutants to the water column, as well as impacts on dredging operations and on the fate of potentially dangerous objects on the seafloor. The objectives of this study are to better understand controls on bed erodibility in estuarine environments, including the roles of sediment grain size, water content, percent organics, and bed fabric, as well as effects of tides, storms, salinity distribution, river discharge, and location within the estuary. An extensive set of erosion …


Electronic Effects In A Cyclization Cascade To Diversified, Polycyclic, Helical Molecules, Caleb Lee Burns Jan 2021

Electronic Effects In A Cyclization Cascade To Diversified, Polycyclic, Helical Molecules, Caleb Lee Burns

Dissertations, Theses, and Masters Projects

Heterocyclic aromatic compounds and their derivatives are ubiquitous in the pharmaceutical and photochemical industries. Naphthochromene derivatives in particular have garnered great interest for their photochemical properties and biological activity. Herein, the effects of electronics on a three-step cascade reaction between aryl substituted 2-(4-aryl-3-((triethylsilyl)oxy)but-1-yn-1-yl)phenols and structurally diverse aldehydes is explored. The cascade is initiated by alkynyl substrate addition to BF3-activated aldehydes. The aldehyde undergoes condensation with the substrate phenol moiety forming an oxocarbenium ion, this initiates the alkynyl-Prins cyclization forming a new six-membered heterocyclic ring with an internal alkenyl cation. The cation is subsequently trapped by a Friedel-Crafts (FC) reaction by …


Investigating The Electron Transfer Dynamics Of Eosin Y Photosensitizers Using Single Molecule Spectroscopy, Kelly Margaret Kopera Jan 2021

Investigating The Electron Transfer Dynamics Of Eosin Y Photosensitizers Using Single Molecule Spectroscopy, Kelly Margaret Kopera

Dissertations, Theses, and Masters Projects

Growing global energy demands have necessitated the search for alternative sources of renewable fuels. Dye-sensitized photocatalysis (DSP) is a promising low cost, sustainable method that directly converts solar energy to readily usable forms of energy such as hydrogen fuel. While DSP is a promising technology, its efficiency is limited by back electron transfer and kinetic redundancy. In order to fully understand these processes, single-molecule spectroscopy (SMS) is used to probe the electron transfer (ET) dynamics of photosensitizers. In particular, eosin Y (EY), a brominated fluorescein derivative that undergoes intersystem crossing prior to injection, is investigated using SMS. In this approach, …


Dihadron Beam Spin Asymmetries On An Unpolarized Hydrogen Target With Clas12, Timothy Barton Hayward Jan 2021

Dihadron Beam Spin Asymmetries On An Unpolarized Hydrogen Target With Clas12, Timothy Barton Hayward

Dissertations, Theses, and Masters Projects

The semi-inclusive deep inelastic scattering process, where an electron scatters off a proton target at high enough energy that the process can be described by the scattering off a single constituent particle, offers targeted access to the internal structure of the nucleon. The process can be described in two phases by parton distribution functions (PDFs), which describe the likelihood of finding a quark or gluon in a particular state inside of the nucleon and then by fragmentation functions (FFs) which describe the likelihood of forming a particular final state particle. One way to study these properties is via the measurement …


Mass Spectrometry-Based Proteomics: An Experimental Study Of Differential Bacteriophage Protein Expression And A Computational Investigation Of The Effects Of Proton Affinity On The Fragmentation Of Proline-Containing Dipeptides, Hao Qian Jan 2021

Mass Spectrometry-Based Proteomics: An Experimental Study Of Differential Bacteriophage Protein Expression And A Computational Investigation Of The Effects Of Proton Affinity On The Fragmentation Of Proline-Containing Dipeptides, Hao Qian

Dissertations, Theses, and Masters Projects

After decades with the development of genetics study, the next step of molecular biology had already been moved onto proteomics. The proteomics study provides an innovative aspect to deduct the relationship between genes and proteins. Meanwhile, research that focuses on the mechanism of protein interactions and intrinsic properties of proteins never cease. The mass spectrometry-based proteomics approaches have already shown their versatile and superior in studying the whole proteome of complicated organisms. This study focuses on practicing bottom-up method in determining and characterizing the expressed proteome of two mycobacteriophages, CrimD and Larva. The expressed proteins of CrimD and Larva in …


Revisiting Isolation For System Security And Efficiency In The Era Of Internet Of Things, Lele Ma Jan 2021

Revisiting Isolation For System Security And Efficiency In The Era Of Internet Of Things, Lele Ma

Dissertations, Theses, and Masters Projects

Isolation is a fundamental paradigm for secure and efficient resource sharing on a computer system. However, isolation mechanisms in traditional cloud computing platforms are heavy-weight or just not feasible to be applied onto the computing environment for Internet of Things(IoT). Most IoT devices have limited resources and their servers are less powerful than cloud servers but are widely distributed over the edge of the Internet. Revisions to the traditional isolation mechanisms are needed in order to improve the system security and efficiency in these computing environments. The first project explores container-based isolation for the emerging edge computing platforms. We show …


High-Dimensional Machine Learning Models In Fintech, Qiong Wu Jan 2021

High-Dimensional Machine Learning Models In Fintech, Qiong Wu

Dissertations, Theses, and Masters Projects

This thesis develops several forecasting models for simultaneously predicting the prices of d assets traded in financial markets, a most fundamental problem in the emerging area of ``FinTech''. The models are optimized to address three critical challenges, C1. High-dimensional interactions between assets. Assets could interact (e.g., Amazon's disclosure of its revenue change in cloud services could indicate that revenues also could change in other cloud providers). The number of possible interactions is quadratic in d, and is often much larger than the number of observations. C2. Non-linearity of the hypothesis class. Linear models are usually insufficient to characterize the relationship …


Acoustic Doppler Current Profiler (Adcp) Data 2017: Ayeyarwady Delta, Myanmar, Courtney K. Harris, Jacob T. Wacht Jan 2021

Acoustic Doppler Current Profiler (Adcp) Data 2017: Ayeyarwady Delta, Myanmar, Courtney K. Harris, Jacob T. Wacht

Data

During December 2017, a 2-week research cruise was conducted on the vessel the Sea Princess by scientists from the Virginia Institute of Marine Science, North Carolina State University, Mawlamyine University, and University of Yangon. Kuehl et al. (2019) and Liu et al. (2020) present some of the sediment core, and seabed mapping data from that cruise. The cruise also provided a unique opportunity to obtain Acoustic Doppler Current Profiler (ADCP) data along several transects from the Gulf of Martaban and adjacent continental shelf offshore of Myanmar. During the cruise, an ADCP was mounted from the boat facing vertically downward toward …


Endangered Species Act: Quantifying Threats Impacting Listing, Delaney Costante Jan 2021

Endangered Species Act: Quantifying Threats Impacting Listing, Delaney Costante

Dissertations, Theses, and Masters Projects

With species increasingly becoming imperiled due to anthropogenic activities, conservation practitioners are tasked with determining conservation priorities in order to make the best use of limited resources. The United States’ Endangered Species Act (ESA) has two listing statuses into which imperiled species are placed to receive protections: Threatened or Endangered. In the first chapter, our objective was to identify differences between Threatened and Endangered species beyond what is outlined in their ESA definitions. To our knowledge, this is the first study to compare listing status for species protected by the ESA on the basis of types and number of threats …


Recruitment And Post-Settlement Mortality Of The Soft-Shell Clam, Mya Arenaria, Shantelle Landry Jan 2021

Recruitment And Post-Settlement Mortality Of The Soft-Shell Clam, Mya Arenaria, Shantelle Landry

Dissertations, Theses, and Masters Projects

The soft-shell clam, Mya arenaria, is a benthic, filter-feeding, infaunal clam typically found in intertidal and shallow subtidal waters. Chesapeake Bay stocks of M. arenaria have been depleted since the 1960s due to various factors including predation, temperature, low recruitment, habitat loss, disease mortalities, and commercial harvest. As an important prey item for many commercial species, low abundances of these clams are mostly the result of the voracious appetite of the blue crab, Callinectes sapidus. In addition to predation, summer water temperatures in the Chesapeake Bay are likely driving the low abundances of M. arenaria, as water temperatures commonly surpass …


On Supporting Android Software Developers And Testers, Carlos Eduardo Bernal Cardenas Jan 2021

On Supporting Android Software Developers And Testers, Carlos Eduardo Bernal Cardenas

Dissertations, Theses, and Masters Projects

Users entrust mobile applications (apps) to help them with different tasks in their daily lives. However, for each app that helps to finish a given task, there are a plethora of other apps in popular marketplaces that offer similar or nearly identical functionality. This makes for a competitive market where users will tend to favor the highest quality apps in most cases. Given that users can easily get frustrated by apps which repeatedly exhibit bugs, failures, and crashes, it is imperative that developers promptly fix problems both before and after the release. However, implementing and maintaining high quality apps is …


Light-Matter Interactions In Quasi-Two-Dimensional Geometries, David James Lahneman Jan 2021

Light-Matter Interactions In Quasi-Two-Dimensional Geometries, David James Lahneman

Dissertations, Theses, and Masters Projects

Emergent phenomena that occur at length scales smaller than approximately half the wavelength of light cannot be resolved by conventional optical techniques due to the Abbe diffraction limit. Scattering-type scanning near-field infrared microscopy (S-SNIM) can circumvent this diffraction limit allowing infrared spectroscopy at nano-scale dimensions independent of the wavelength. Additionally, there is enhanced surface sensitivity resulting from this nanoconfinement of infrared light. S-SNIM is uniquely suitable to study a diverse range of material properties inaccessible by far-field optics in the infrared such as the optical properties of ultrathin films as well as hybrid light matter surface waves called polaritons. Initially, …


Dealing With Many Species: Improving Methodology For Forming And Assessing Species Complexes, Kristen Omori Jan 2021

Dealing With Many Species: Improving Methodology For Forming And Assessing Species Complexes, Kristen Omori

Dissertations, Theses, and Masters Projects

In the United States, the Magnuson-Stevens Reauthorization Act mandates that all federally fished species must have catch limits, which can be challenging for data-limited species. One approach is to assess and manage a group of species with similar life history characteristics, vulnerability to the fishery, and overlapping geographic distributions in a single management unit, or a complex (i.e., stock or species complex). Using the Gulf of Alaska (GOA) Other Rockfish complex as a case study, the main goals of this dissertation are five-fold: 1) review species complexes in the United States; 2) compare multivariate techniques for assigning species to complexes; …


Improving Observation, Assessment, And Management Of Atlantic Coastal Sharks, Cassidy Dawn Peterson Jan 2021

Improving Observation, Assessment, And Management Of Atlantic Coastal Sharks, Cassidy Dawn Peterson

Dissertations, Theses, and Masters Projects

Coastal sharks represent a group of stocks for which observation, assessment, and management are particularly challenging. Large distributional ranges, complex migratory behavior, low economic value, and relatively few observations in fishery independent surveys hinder relative abundance estimation. Assessing stock status of coastal sharks is encumbered by limited data availability, data quality, and knowledge of life history strategy. Further, coastal sharks are challenging to manage due to their slow intrinsic population growth rates, competing stakeholder interests, history of overexploitation, and in some cases, subjection to international exploitation. This dissertation aimed to improve the capacity to observe relative abundance of coastal sharks. …


Uncovering Information Operations On Twitter Using Natural Language Processing And The Dynamic Wavelet Fingerprint, Spencer Lee Kirn Jan 2021

Uncovering Information Operations On Twitter Using Natural Language Processing And The Dynamic Wavelet Fingerprint, Spencer Lee Kirn

Dissertations, Theses, and Masters Projects

Information Operations (IO) are campaigns waged by covert, powerful entities to distort public discourse in a direction that is advantageous for them. It is the behaviors of the underlying networks that signal these campaigns in action, not the specific content they are posting. In this dissertation we introduce a social media analysis system that uncovers these behaviors by analyzing the specific post timings of underlying accounts and networks. The presented method first clusters tweets based on content using Natural Language Processing (NLP). Each of these clusters - referred to as topics - are plotted in time using the attached metadata …


Gis Data: Dorchester County, Maryland - Shoreline Inventory Data 2020, Karinna Nunez, Marcia Berman, Sharon Killeen, Jessica Hendricks, Tamia Rudnicky, Catherine Riscassi Jan 2021

Gis Data: Dorchester County, Maryland - Shoreline Inventory Data 2020, Karinna Nunez, Marcia Berman, Sharon Killeen, Jessica Hendricks, Tamia Rudnicky, Catherine Riscassi

Data

The shoreline inventory files have been generated to support the application of the Maryland Shoreline Stabilization Model (SSM), developed by the Center for Coastal Resources Management (CCRM), Virginia Institute of Marine Science (VIMS), to enhance and streamline regulatory decision making in Maryland. This shoreline inventory includes the features needed as inputs to run the SSM.

The data developed for the Shoreline Inventory is based on a three-tiered shoreline assessment approach. This assessment characterizes conditions by using observations made remotely at the desktop using high resolution imagery. The three-tiered shoreline assessment approach divides the shorezone into three regions:

1) the immediate …


Ware River Intensive Watershed Study Data Files: Part 1. Nonpoint Source Contributions, Gary F. Anderson Jan 2021

Ware River Intensive Watershed Study Data Files: Part 1. Nonpoint Source Contributions, Gary F. Anderson

Data

The Ware River is a small coastal estuary draining into the Chesapeake Bay estuary. VIMS monitored the Ware watershed for rain events, runoff, and impacts to the estuary from April 1979 through July 1981.

This entry contains the runoff volume, rainfall and water quality monitoring data files for the portion of the study known as Part 1 – Nonpoint source contributions. Streams and small catchments representing suburban, agricultural and forested small basins were monitored regularly and during large rainfall events to estimate pollution loading to the estuary from the watershed. Methods and results are documented in the related literature. Data …


Radiofrequency Ac Zeeman Trapping For Neutral Atoms, Andrew Peter Rotunno Jan 2021

Radiofrequency Ac Zeeman Trapping For Neutral Atoms, Andrew Peter Rotunno

Dissertations, Theses, and Masters Projects

This thesis presents the first experimental demonstration of a two-wire AC Zeeman trap on an atom chip. The AC Zeeman energy is a resonant, bipolar, state-dependent atomic energy shift produced by alternating magnetic fields with frequencies near hyperfine transitions. We demonstrate that high gradients in this energy, as near an atom chip, can produce a spin-state selective force greater than gravity for ultracold rubidium atoms. Our novel trap is generated by a local minimum in AC Zeeman energy. Using less than one watt of power, we demonstrate trap frequency on the order of a few hundred Hz, trap depth about …


Forward & Off-Forward Parton Distributions From Lattice Qcd, Colin Paul Egerer Jan 2021

Forward & Off-Forward Parton Distributions From Lattice Qcd, Colin Paul Egerer

Dissertations, Theses, and Masters Projects

The interpretation of (semi-)inclusive and certain exclusive scattering processes relies on the factorization of hard parton level cross sections from long-range and non-perturbative parton correlations. The familiar Parton Distribution Functions (PDFs) and Generalized Parton Distributions quantify the non-perturbative dynamics in these situations and address a number of key questions surrounding the structure of hadrons. A certain class of matrix elements accessible in lattice QCD, so called Lattice Cross Sections, have been shown to factorize into these collinear distributions in a manner akin to the factorization of hadronic cross sections. In the short-distance regime, matrix elements of space-like separated two-current operators …