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William & Mary

2022

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Articles 1 - 30 of 282

Full-Text Articles in Physical Sciences and Mathematics

On The Relative Importance Of Offshelf/Onshelf Drivers Of Variability In Mcdw Inventory On The Amundsen Shelf, Antarctica, Pierre St-Laurent, S. E. Stammerjohn, T. Maksym, R. M. Sherrell Dec 2022

On The Relative Importance Of Offshelf/Onshelf Drivers Of Variability In Mcdw Inventory On The Amundsen Shelf, Antarctica, Pierre St-Laurent, S. E. Stammerjohn, T. Maksym, R. M. Sherrell

Presentations

Ice shelves in the Amundsen Sea (west Antarctica) are melting rapidly and may raise global sea levels substantially over the coming century through reduced buttressing. The high basal melt rates are associated with the presence of warm modified Circumpolar Deep Water (mCDW) that intrudes across the continental shelf and melts the floating portion of the ice sheet from its base near the grounding zone. How much mCDW is present on the continental shelf (its volume inventory) is thus thought to be a key proxy for the year-to-year variability in ice shelf melt rates. Over the past decade, the literature has …


Voting Rules And Properties, Zhuorong Mao Dec 2022

Voting Rules And Properties, Zhuorong Mao

Undergraduate Honors Theses

This thesis composes of two chapters. Chapter one considers the higher order of Borda Rules (Bp) and the Perron Rule (P) as extensions of the classic Borda Rule. We study the properties of those vector-valued voting rules and compare them with Simple Majority Voting (SMV). Using simulation, we found that SMV can yield different results from B1, B2, and P even when it is transitive. We also give a new condition that forces SMV to be transitive, and then quantify the frequency of transitivity when it fails.

In chapter two, we study the `protocol paradox' of approval voting. In approval …


Increasing Use Of Natural And Nature-Based Features To Build Resilience To Storm-Driven Flooding, Final Report, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Pamela Mason, Jessica Hendricks, Julie Herman, Karen Duhring, Carl Hershner Nov 2022

Increasing Use Of Natural And Nature-Based Features To Build Resilience To Storm-Driven Flooding, Final Report, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Pamela Mason, Jessica Hendricks, Julie Herman, Karen Duhring, Carl Hershner

Reports

In coastal Virginia today, local governments are dealing with recurrent flooding driven by coastal storms, exacerbated by rising sea level and increased frequency of intense rain events. At the same time, they are confronted with increasing demands on limited resources to address issues coastal flooding in concert with water quality, wetlands management, shoreline erosion, habitat, and community needs such as infrastructure, flood insurance and open space. One solution is to maximize the protection of existing and implement new natural and nature-based features (NNBFs) to capitalize on the provision of multiple benefits to address many of these coastal issues.

There are …


Gis Data: Charles County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Nov 2022

Gis Data: Charles County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions:

1) the …


New Guidance To Build Resiliency And Mitigate For Sea Level Rise As Elements Of The Chesapeake Bay Preservation Act, Pamela Mason, Julie Herman, Christine Tombleson, Jessica Hendricks, Karen Duhring Nov 2022

New Guidance To Build Resiliency And Mitigate For Sea Level Rise As Elements Of The Chesapeake Bay Preservation Act, Pamela Mason, Julie Herman, Christine Tombleson, Jessica Hendricks, Karen Duhring

Reports

The Center for Coastal Resources Management (CCRM), Virginia Institute of Marine Science (VIMS), worked in collaboration with the Virginia Department of Environmental Quality (DEQ) and the Virginia Coastal Policy Center (VCPC) to develop guidance to inform the implementation of Chesapeake Bay Preservation Act (CBPA) regulations promulgated in 2021. The 2021 regulations added provisions to require local governments to consider climate changes, specifically flooding, sea level rise and storms, and the preservation of mature trees in the administration of the CBPA program. Specifically, CCRM developed analytical data using criteria specified in the CBPA regulations, of the National Oceanic and Atmospheric Administration …


'Flux+Mutability': A Conditional Generative Approach To One-Class Classification And Anomaly Detection, Cristiano Fanelli, James Giroux, Z. Papandreou Nov 2022

'Flux+Mutability': A Conditional Generative Approach To One-Class Classification And Anomaly Detection, Cristiano Fanelli, James Giroux, Z. Papandreou

Arts & Sciences Articles

Anomaly Detection is becoming increasingly popular within the experimental physics community. At experiments such as the Large Hadron Collider, anomaly detection is growing in interest for finding new physics beyond the Standard Model. This paper details the implementation of a novel Machine Learning architecture, called Flux+Mutability, which combines cutting-edge conditional generative models with clustering algorithms. In the 'flux' stage we learn the distribution of a reference class. The 'mutability' stage at inference addresses if data significantly deviates from the reference class. We demonstrate the validity of our approach and its connection to multiple problems spanning from one-class classification to anomaly …


Gis Data: Worcester County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Nov 2022

Gis Data: Worcester County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions: 1) the …


Gis Data: St Mary’S County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Nov 2022

Gis Data: St Mary’S County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions:

1) the …


Gis Data: Somerset County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Nov 2022

Gis Data: Somerset County, Maryland – Shoreline Inventory Data 2021, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions: 1) the …


Norfolk, Virginia Federal Flood Risk Management Study, Jian Shen, Rico Wang, Mac Sisson Sep 2022

Norfolk, Virginia Federal Flood Risk Management Study, Jian Shen, Rico Wang, Mac Sisson

Reports

The City of Norfolk and Norfolk District, U.S. Army Corps of Engineers (USACE), are partnering to conduct a Coastal Storm Risk Management Study (CSRM) study to determine the Federal interest and feasibility of alternatives to mitigate coastal flooding risk in the City. The CSRM is in the Feasibility Study (FS) phase in which alternatives are proposed and developed to conceptual/preliminary design level, benefit/cost analyses are conducted, and environmental studies are completed to comply with the National Environmental Policy Act (NEPA). The magnitude of the feasibility study will require an Environmental Impact Statement (EIS).

A component of the FS/EIS is the …


Gis Data: Kent County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Sep 2022

Gis Data: Kent County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions:

1) the …


Gis Data: Baltimore County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Sep 2022

Gis Data: Baltimore County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions:

1) the …


Deep Learning Fusion Of Satellite And Social Information To Estimate Human Migratory Flows, Daniel Runfola, Heather Baier, Laura Mills, Maeve Naughton-Rockwell, Anthony Stefanidis Sep 2022

Deep Learning Fusion Of Satellite And Social Information To Estimate Human Migratory Flows, Daniel Runfola, Heather Baier, Laura Mills, Maeve Naughton-Rockwell, Anthony Stefanidis

Arts & Sciences Articles

Human migratory decisions are driven by a wide range of factors, including economic and environmental condi-tions, conflict, and evolving social dynamics. These factors are reflected in disparate data sources, including house-hold surveys, satellite imagery, and even news and social media. Here, we present a deep learning- based data fusion technique integrating satellite and census data to estimate migratory flows from Mexico to the United States. We leverage a three-stage approach, in which we (1) construct a matrix- based representation of socioeconomic information for each municipality in Mexico, (2) implement a convolutional neural network with both satellite imagery and the constructed …


Gis Data: Queen Anne’S County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Sep 2022

Gis Data: Queen Anne’S County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions:

1) the …


Gis Data: Baltimore City, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Sep 2022

Gis Data: Baltimore City, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions:

1) the …


Gis Data: Wicomico County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill Sep 2022

Gis Data: Wicomico County, Maryland – Shoreline Inventory Data 2022, Karinna Nunez, Tamia Rudnicky, Sharon Killeen, Jessica Hendricks, Catherine R. Duning, Evan Hill

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 shore zone into three regions:

1) the …


Influence Of Oyster Genetic Background On Levels Of Human-Pathogenic Vibrio Spp., Corinne Audemard, Kimberly S. Reece, Robert J. Latour, Lydia M. Bienlien, Ryan B. Carnegie Aug 2022

Influence Of Oyster Genetic Background On Levels Of Human-Pathogenic Vibrio Spp., Corinne Audemard, Kimberly S. Reece, Robert J. Latour, Lydia M. Bienlien, Ryan B. Carnegie

VIMS Articles

Human-pathogenic Vibrio bacteria are common inhabitants of oyster tissues, but our understanding of factors driving the wide range of concentrations found in individual oysters is extremely limited. We examined the influence of oyster sex and parasitism in light of their profound effects on oyster tissues against a backdrop of eastern oysters, Crassostrea virginica, from two diploid and two triploid aquacultured lines. This allowed us to examine not only the effect of oyster ploidy but also of oyster genetics, a factor never investigated with regard to human-pathogenic Vibrio species. We measured levels of total Vibrio vulnificus (vvhA), and of …


Chesapeake Bay National Estuarine Research Reserve In Virginia Management Plan: 2022-2027, W. G. Reay, J. Baber, H. Brooks, A. Demeo, C. T. Friedrichs, C. Gonzales, J. Kuriawa, T. Hooper, S. Lerberg, E. J. Miles, B. Neikirk, S. Nuss, L. Ott, D. Parrish, T. Rudo, E C. Shields, S. Snyder, S. Wood Aug 2022

Chesapeake Bay National Estuarine Research Reserve In Virginia Management Plan: 2022-2027, W. G. Reay, J. Baber, H. Brooks, A. Demeo, C. T. Friedrichs, C. Gonzales, J. Kuriawa, T. Hooper, S. Lerberg, E. J. Miles, B. Neikirk, S. Nuss, L. Ott, D. Parrish, T. Rudo, E C. Shields, S. Snyder, S. Wood

Reports

Established through the Coastal Zone Management Act, the National Estuarine Research Reserve System (NERRS) represents a partnership program between the National Oceanic and Atmospheric Administration (NOAA) and the coastal states to promote informed management of the Nation’s estuaries and habitats. Designated in 1991, and administered by the Virginia Institute of Marine Science (VIMS) of William & Mary, the Chesapeake Bay National Estuarine Research Reserve in Virginia (CBNERR-VA or Reserve) is one of 30 protected areas, which encompass over 1.3 million acres and make up the NERRS.

As the nation's largest estuary, the Chesapeake Bay contains a diverse collection of habitats …


Shear Turbulence In The High-Wind Southern Ocean Using Direct Measurements, Laur Ferris, Carole Anne Clayson, Donglai Gong, Et Al Jul 2022

Shear Turbulence In The High-Wind Southern Ocean Using Direct Measurements, Laur Ferris, Carole Anne Clayson, Donglai Gong, Et Al

VIMS Articles

The ocean surface boundary layer is a gateway of energy transfer into the ocean. Wind-driven shear and meteorologically forced convection inject turbulent kinetic energy into the surface boundary layer, mixing the upper ocean and transforming its density structure. In the absence of direct observations or the capability to resolve sub-grid scale 3D turbulence in operational ocean models, the oceanography community relies on surface boundary layer similarity scalings (BLS) of shear and convective turbulence to represent this mixing. Despite their importance, near-surface mixing processes (and ubiquitous BLS representations of these processes) have been under-sampled in high energy forcing regimes such as …


Precision Determination Of The Neutral Weak Form Factor Of ^48ca, D. Adhikari, (...), David S. Armstrong, Et Al. Jul 2022

Precision Determination Of The Neutral Weak Form Factor Of ^48ca, D. Adhikari, (...), David S. Armstrong, Et Al.

Arts & Sciences Articles

We report a precise measurement of the parity-violating (PV) asymmetry APV in the elastic scattering of longitudinally polarized electrons from 48Ca. We measure APV=2668±106(stat)±40(syst) parts per billion, leading to an extraction of the neutral weak form factor FW(q=0.8733  fm−1)=0.1304±0.0052(stat)±0.0020(syst) and the charge minus the weak form factor Fch−FW=0.0277±0.0055. The resulting neutron skin thickness Rn−Rp=0.121±0.026(exp)±0.024(model)  fm is relatively thin yet consistent with many model calculations. The combined CREX and PREX results will have implications for future energy density functional calculations and on the density dependence of the symmetry energy of nuclear matter.


Beyond The Petermann Limit: Prospect Of Increasing Sensor Precision Near Exceptional Points, David D. Smith, Hongrok Chang, Eugeniy E. Mikhailov, Selim M. Shahriar Jul 2022

Beyond The Petermann Limit: Prospect Of Increasing Sensor Precision Near Exceptional Points, David D. Smith, Hongrok Chang, Eugeniy E. Mikhailov, Selim M. Shahriar

Arts & Sciences Articles

Experiments near the lock-in region in maximally dissipative non-Hermitian systems, e.g., conventional laser gyroscopes near the deadband, have run up against the Petermann limit, where excess noise exactly cancels any scale-factor enhancement resulting in no overall enhancement in precision. As a result, one might be tempted to conclude that exceptional points (EPs) generally cannot be used to increase the precision of laser sensors. Indeed, using a linear eigenmode analysis we show that the Petermann limit applies not just to maximally dissipative systems, but for any type of EP, owing to the fact that EPs are rotationally invariant. It turns out, …


Campus Nature Rx: How Investing In Nature Interventions Benefits College Students, Donald A. Rakow, Dorothy C. Ibes Jul 2022

Campus Nature Rx: How Investing In Nature Interventions Benefits College Students, Donald A. Rakow, Dorothy C. Ibes

Arts & Sciences Articles

Excerpt from article: "The college experience is a time of discovery, learning, and personal growth. However, many U.S. college students report unprecedentedly high levels of mental health problems during these formative years. According to the 2021 National Collegiate Health Assessment, over 30 percent of students received psychological or mental health services in the previous 12 months..."


Wind-Modulated Western Maine Coastal Current And Its Connectivity With The Eastern Maine Coastal Current, Denghui Li, Zhengui Wang, Huijie Xue, Andrew C. Thomas, Ron J. Etter Jun 2022

Wind-Modulated Western Maine Coastal Current And Its Connectivity With The Eastern Maine Coastal Current, Denghui Li, Zhengui Wang, Huijie Xue, Andrew C. Thomas, Ron J. Etter

VIMS Articles

Using a high-resolution circulation model and an offline particle tracking model, we investigated variations of the Western Maine Coastal Current (WMCC) and its connectivity with the Eastern Maine Coastal Current (EMCC). The models showed that the weak, broad, and sinuous WMCC is generally southwestward with an offshore and a nearshore core, fed by the extension of the EMCC and runoff from the Penobscot and Kennebec–Androscoggin Rivers, respectively. A sea-level dome can form offshore of Casco Bay in late fall and early winter as the northeastward alongshore wind sets up a seaward sea-level gradient from the coast to meet the shoreward …


Vims Marine Science Day, Virginia Institute Of Marine Science Jun 2022

Vims Marine Science Day, Virginia Institute Of Marine Science

Miscellaneous

Brochure describing demonstrations and activities on this day of community outreach.


Town Of Colonial Beach Survey Of Central And Castlewood Beaches, Donna A. Milligan, C. Scott Hardaway Jr., Cameron W. Green, Alexander R. Milligan Jun 2022

Town Of Colonial Beach Survey Of Central And Castlewood Beaches, Donna A. Milligan, C. Scott Hardaway Jr., Cameron W. Green, Alexander R. Milligan

Reports

The Town of Colonial Beach occupies a peninsula between the Potomac River and Monroe Bay. Approximately 2.5 miles of the shoreline is publicly-owned. Two areas on the Potomac River have been enhanced as recreational beaches for swimming and sunbathing. Central Beach is located just south of the Town Pier and is the main recreational beach. Castlewood Beach is south of Central Beach near the entrance to Monroe Bay.


Orbital-Selective Metallicity In The Valence-Bond Liquid Phase Of Li2 Ruo3, Patrick Mcardle, Fei-Ting Huang, Junjie Yang, (...), M. M. Qazilbash Jun 2022

Orbital-Selective Metallicity In The Valence-Bond Liquid Phase Of Li2 Ruo3, Patrick Mcardle, Fei-Ting Huang, Junjie Yang, (...), M. M. Qazilbash

Arts & Sciences Articles

Li2RuO3 (LRO) forms a valence bond crystal at room temperature. It undergoes a high temperature phase transition that involves structural, magnetic, and electronic changes leading to an exotic valence bond liquid state. The orbital degrees of freedom are thought to be fundamental to the evolution of LRO properties across the phase transition. We report temperature dependent broadband (100–26000cm–1) reflectance measurements on single crystals of LRO to elucidate structural and transport properties. Specifically, the phonon and electronic properties of LRO were investigated through the phase transition. We report that above the transition temperature (Tc≈500K), the optical band gap closes for electrons …


Sediment Characteristics Of The Chesapeake Bay And Its Tributaries, Virginia Province: Data Files, Gary F. Anderson Jun 2022

Sediment Characteristics Of The Chesapeake Bay And Its Tributaries, Virginia Province: Data Files, Gary F. Anderson

Data

During the 1990’s, Dr. Maynard Nichols and colleagues at the Virginia Institute of Marine Science compiled digital databases of sediment observations in the Chesapeake Bay and other coastal bays and rivers. These projects were performed under several cooperative agreements with NOAA, EPA and USGS. This particular dataset covers the Chesapeake Bay for bulk properties and contaminants. Additional references are provided below. The original files and filenames are provided without edit. See the readme.txt file for overall explanation of the datasets and individual .DOC files for the data dictionary and further data processing information for each waterbody.


The Probability Mass Function Of The Kaplan-Meier Product-Limit Estimator, Yuxin Qin, Heather Sasinowska, Lawrence Leemis May 2022

The Probability Mass Function Of The Kaplan-Meier Product-Limit Estimator, Yuxin Qin, Heather Sasinowska, Lawrence Leemis

Arts & Sciences Articles

Kaplan andMeier’s 1958 article developed a nonparametric estimator of the survivor function from a right censored dataset. Determining the size of the support of the estimator as a function of the sample size provides a challenging exercise for students in an advanced course in mathematical statistics. We devise two algorithms for calculating the support size and calculate the associated probability mass function for small sample sizes and particular probability distributions for the failure and censoring times.


Quantum Federated Learning: Training Hybrid Neural Networks Collaboratively, Anneliese Brei May 2022

Quantum Federated Learning: Training Hybrid Neural Networks Collaboratively, Anneliese Brei

Undergraduate Honors Theses

This thesis explores basic concepts of machine learning, neural networks, federated learning, and quantum computing in an effort to better understand Quantum Machine Learning, an emerging field of research. We propose Quantum Federated Learning (QFL), a schema for collaborative distributed learning that maintains privacy and low communication costs. We demonstrate the QFL framework and local and global update algorithms with implementations that utilize TensorFlow Quantum libraries. Our experiments test the effectiveness of frameworks of different sizes. We also test the effect of changing the number of training cycles and changing distribution of training data. This thesis serves as a synoptic …


Modern Theory Of Copositive Matrices, Yuqiao Li May 2022

Modern Theory Of Copositive Matrices, Yuqiao Li

Undergraduate Honors Theses

Copositivity is a generalization of positive semidefiniteness. It has applications in theoretical economics, operations research, and statistics. An $n$-by-$n$ real, symmetric matrix $A$ is copositive (CoP) if $x^T Ax \ge 0$ for any nonnegative vector $x \ge 0.$ The set of all CoP matrices forms a convex cone. A CoP matrix is ordinary if it can be written as the sum of a positive semidefinite (PSD) matrix and a symmetric nonnegative (sN) matrix. When $n < 5,$ all CoP matrices are ordinary. However, recognizing whether a given CoP matrix is ordinary and determining an ordinary decomposition (PSD + sN) is still an unsolved problem. Here, we give an overview on modern theory of CoP matrices, talk about our progress on the ordinary recognition and decomposition problem, and emphasis the graph theory aspect of ordinary CoP matrices.