Physical Sciences and Mathematics Commons^™

Odu Sea Level Rise Initiative Featured In Premier Higher Education Publication, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

President Broderick's Leadership In Sea Level Rise Initiative Featured In Nation's Top Higher Education Publication, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

Community Discussion: Catch The King Tide, Amy Matzke-Fawcett

News Items

No abstract provided.

Community Invited To Discuss King Tide Event, Amy Matzke-Fawcett

News Items

No abstract provided.

Distributions Of Krill And Antarctic Silverfish And Correlations With Environmental Variables In The Western Ross Sea, Antarctica, L. Brynn Davis, Eileen E. Hofmann, John M. Klinck, Andrea Piñones, Michael S. Dinniman

CCPO Publications

Antarctic krill Euphausia superba, crystal krill E. crystallorophias, and Antarctic silverfish Pleuragramma antarctica are key mid-trophic level species in the Ross Sea, connecting primary production to the upper trophic levels. Distributions of these species were constructed from observations made in the western Ross Sea from 1988 to 2004. Distributions of environmental conditions were obtained from a 5-km resolution circulation model (temperature, mixed layer depth, surface speed) and satellite-derived observations (chlorophyll, sea ice cover). A hierarchy of statistical methods determined correlations and relationships between species and environmental conditions. Each species occupies a localized habitat defined by different environmental characteristics. …

Molecular Geometries And Other Properties Of H2o⋯Agi And H3n⋯Agi As Characterised By Rotational Spectroscopy And Ab Initio Calculations, Chris Medcraft, Eva Gougoula, Dror M. Bittner, John C. Mullaney, Susana Blanco, David P. Tew, Nicholas R. Walker, Anthony C. Legon

Chemistry & Biochemistry Faculty Publications

The rotational spectra of H₃N⋯AgI and H₂O⋯AgI have been recorded between 6.5 and 18.5 GHz by chirped-pulse Fourier-transform microwave spectroscopy. The complexes were generated through laser vaporisation of a solid target of silver or silver iodide in the presence of an argon gas pulse containing a low concentration of the Lewis base. The gaseous sample subsequently undergoes supersonic expansion which results in cooling of rotational and vibrational motions such that weakly bound complexes can form within the expanding gas jet. Spectroscopic parameters have been determined for eight isotopologues of H₃N⋯AgI and six isotopologues of …

User Preferences For Flood Alerts (Risk Communication And Public Engagement In Sea Level Rise Resilience Research Series, Paper No. 2), Juita-Elena (Wie) Yusuf, Carol Considine, Michelle Covi, Donta Council

Occasional Paper Series

Working with faculty and staff from Old Dominion University’s Center for Coastal Physical Oceanography, we developed a “straw man” website for users to sign up to receive flood alerts. The flood alert is based on tidal projections for the Sewell’s Point tide gauge available from the National Weather Service through the meteorological development laboratory (http://www.nws.noaa.gov/mdl/etsurge/index.php) and sends alerts for projected water level. We recruited study participants for one-on-one interviews. Participants were asked to interact with the flood alert signup interface and respond to specific questions about their preferences for flood alerts. We used findings of the one-on-one interviews to create …

A Glimpse Of Gluons Through Deeply Virtual Compton Scattering On The Proton, M. Defurne, A. Marti Jimenez-Arguello, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, M. N. H. Rashad

Physics Faculty Publications

The internal structure of nucleons (protons and neutrons) remains one of the greatest outstanding problems in modern nuclear physics. By scattering high-energy electrons off a proton we are able to resolve its fundamental constituents and probe their momenta and positions. Here we investigate the dynamics of quarks and gluons inside nucleons using deeply virtual Compton scattering (DVCS)-a highly virtual photon scatters off the proton, which subsequently radiates a photon. DVCS interferes with the Bethe-Heitler (BH) process, where the photon is emitted by the electron rather than the proton. We report herein the full determination of the BH-DVCS interference by exploiting …

Lattice Qcd Exploration Of Parton Pseudo-Distribution Functions, Kostas Orginos, Anatoly Radyushkin, Joseph Karpie, Savvas Zafeiropoulos

Physics Faculty Publications

We demonstrate a new method of extracting parton distributions from lattice calculations. The starting idea is to treat the generic equal-time matrix element M(Pz(3), z(3)(2)) as a function of the Ioffe time nu = Pz(3) and the distance z(3). The next step is to divide M(Pz(3), z(3)(2)) by the rest-frame density M(0, z(3)(2)). Our lattice calculation shows a linear exponential z(3)-dependence in the rest-frame function, expected from the Z(z(3)(2)) factor generated by the gauge link. Still, we observe that the ratio M (Pz(3), z(3)(2))/M(Pz(3), z(3)(2)) has a Gaussian-type behavior with respect to z(3) for 6 values of P used in …

Surface Impedance And Optimum Surface Resistance Of A Superconductor With An Imperfect Surface, Alex Gurevich, Takayuki Kubo

Physics Faculty Publications

We calculate a low-frequency surface impedance of a dirty, s-wave superconductor with an imperfect surface incorporating either a thin layer with a reduced pairing constant or a thin, proximity-coupled normal layer. Such structures model realistic surfaces of superconducting materials which can contain oxide layers, absorbed impurities, or nonstoichiometric composition. We solved the Usadel equations self-consistently and obtained spatial distributions of the order parameter and the quasiparticle density of states which then were used to calculate a low-frequency surface resistance R_s (T) and the magnetic penetration depth λ(T) as functions of temperature in the limit of local London electrodynamics. It …

First Exclusive Measurement Of Deeply Virtual Compton Scattering Off 4He: Toward The 3d Tomography Of Nuclei, M. Hattawy, N. A. Baltzell, R. Dupré, K. Hafidi, S. Stepanyan, S. Bültmann, R. De Vita, A. El Alaoui, L. El Fassi, H. Egiyan, B. Torayev, D. Adikaram, M. J. Amaryan, G. Charles, M. Khachatryan, A. Klein, S. E. Kuhn, M. Mayer, Y. Prok, L. B. Weinstein, Z. W. Zhao

Physics Faculty Publications

We report on the first measurement of the beam-spin asymmetry in the exclusive process of coherent deeply virtual Compton scattering off a nucleus. The experiment uses the 6 GeV electron beam from the Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab incident on a pressurized ⁴He gaseous target placed in front of the CEBAF Large Acceptance Spectrometer (CLAS). The scattered electron is detected by CLAS and the photon by a dedicated electromagnetic calorimeter at forward angles. To ensure the exclusivity of the process, a specially designed radial time projection chamber is used to detect the recoiling ^{4 …}

Deglacial Tropical Atlantic Subsurface Warming Links Ocean Circulation Variability To The West African Monsoon, Matthew W. Schmidt, Ping Chang, Andrew O. Parker, Link Ji, Feng He

OES Faculty Publications

Multiple lines of evidence show that cold stadials in the North Atlantic were accompanied by both reductions in Atlantic Meridional Overturning Circulation (AMOC) and collapses of the West African Monsoon (WAM). Although records of terrestrial change identify abrupt WAM variability across the deglaciation, few studies show how ocean temperatures evolved across the deglaciation. To identify the mechanism linking AMOC to the WAM, we generated a new record of subsurface temperature variability over the last 21 kyr based on Mg/Ca ratios in a sub-thermocline dwelling planktonic foraminifera in an Eastern Equatorial Atlantic (EEA) sediment core from the Niger Delta. Our subsurface …

Regional Sea Level Variability And Trends, 1960-2007: A Comparison Of Sea Level Reconstructions And Ocean Syntheses, M. Carson, A. Köhl, D. Stammer, B. Meyssignac, J. Church, J. Schröter, M. Wenzel, B. Hamlington

OES Faculty Publications

Several existing statistical and dynamical reconstructions of past regional sea level variability and trends are compared with each other and with tide gauges over the 48 year period 1960-2007, partially predating the satellite altimetry era. Evaluated statistical reconstructions were built from tide-gauge data (TGR), and dynamical reconstructions from ocean data assimilation (ODA) approaches. Although most of the TGRs yield global-mean time series of sea level with trends deviating within ± 0.1 mm y^r-1, the spatial anomalies of the trends deviate substantially between the reconstructions over the period predating altimetry. In contrast, TGRs match observed regional trend patterns fairly …

Characterization Of Laser-Generated Aluminum Plasma Using Ion Time-Of-Flight And Optical Emission Spectroscopy, Md. Haider A. Shaim, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Laser plasma generated by ablation of an Al target in vacuum is characterized by ion time-of-flight combined with optical emission spectroscopy. A Q-switched Nd:YAG laser (wavelength λ = 1064 nm, pulse width τ ∼ 7 ns, and fluence F ≤ 38 J/cm²) is used to ablate the Al target. Ion yield and energy distribution of each charge state are measured. Ions are accelerated according to their charge state by the double-layer potential developed at the plasma-vacuum interface. The ion energy distribution follows a shifted Coulomb-Boltzmann distribution. Optical emission spectroscopy of the Al plasma gives significantly lower plasma temperature …

Circulation, Vol. 23, No. 1, Center For Coastal Physical Oceanography, Old Dominion University, Bem Hamlington

CCPO Circulation

Fall 2017 issue of CCPO Circulation featuring article "Leading the Way Toward Better Projections of Regional Sea Level Rise" by Ben Hamlington.

The Effects Of Climate On Radial Growth Of Disjunct Northern White Cedar (Thuja Occidentalis L.) In Virginia, Joshua A. Kincaid

Virginia Journal of Science

Understanding the geographic range and growth of species is essential for effective land management in a landscape affected by anthropogenic activity and climate change. Climate change is expected to alter the distribution and growth of many tree species in eastern North America, including northern white cedar (Thuja occidentalis L.). This research examined the effects of climate on radial growth of T. occidentalis in disjunct populations south of its continuous range margin in eastern North America. A T. occidentalis tree-ring chronology was developed and examined for growth-climate interactions. Mean sensitivity of the T. occidentalis chronology was within the range of …

A Comparative Study On Machine Learning Algorithms For Network Defense, Abdinur Ali, Yen-Hung Hu, Chung-Chu (George) Hsieh, Mushtaq Khan

Virginia Journal of Science

Network security specialists use machine learning algorithms to detect computer network attacks and prevent unauthorized access to their networks. Traditionally, signature and anomaly detection techniques have been used for network defense. However, detection techniques must adapt to keep pace with continuously changing security attacks. Therefore, machine learning algorithms always learn from experience and are appropriate tools for this adaptation. In this paper, ten machine learning algorithms were trained with the KDD99 dataset with labels, then they were tested with different dataset without labels. The researchers investigate the speed and the efficiency of these machine learning algorithms in terms of several …

Odu Scientists Address Antarctic Ice Melt Affecting Sea Levels, Miasia Osbey

News Items

No abstract provided.

Origins And Transformations Of Dissolved Organic Matter In Large Arctic Rivers, Karl Kaiser, Maria Canedo-Oropeza, Rachel Mcmahon, Eainer M. W. Amon

OES Faculty Publications

Arctic river watersheds are important components of the global climate system and show an amplified response to climate change. Here, we characterize origins and transformations of dissolved organic matter (DOM) in five major Arctic rivers (Kolyma, Lena, Yenisei, Ob, Mackenzie) over 3 years with seasonal sampling periods using measurements of carbohydrates, amino acids, bacterial biomarkers (D-amino acids), and plant protein biomarkers (hydroxyproline). A strong seasonal cycle of bioavailable DOM export was observed that correlated with discharge, vegetation, river morphology and water residence time. The chemical composition of bioavailable DOM was different among rivers reflecting unique characteristics of Arctic river watersheds. …

Fermi Questions, Question 1: Trumpet Spit; Question 2: Tall Buildings, Larry Weinstein

Physics Faculty Publications

A quiz concerning physics is presented on topics such as the amount of saliva consumed by trumpeter Louis Armstrong during his career and the effect of buildings in the rotational inertia of the planet Earth.

A Picture Is Worth A Thousand Roads, Keith Pierce

News Items

No abstract provided.

Life In Hampton Roads: Sea Level Rise And Flooding, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

Healthcare Outcomes And Resource Utilization Associated With Neonatal Hypoglycemia: Analysis Of Data From The Hcup Kid’S Inpatient Database, Brook T. Alemu

Health Services Research Dissertations

Neonatal hypoglycemia is the most common metabolic abnormality in infants and is associated with neurological damage and death. The risk of developing hypoglycemia among infants born from diabetic mothers is even higher. Although much work has been performed addressing issues for treatment and care, research related to neonatal hypoglycemia has been focused on the clinical or individual level risk factors. Contextual risk factors such as hospital characteristics, neighborhood economic status, and regional variations were not considered in earlier studies. Additionally, although healthcare resources utilization of hypoglycemia has been adequately addressed in the adult population, this topic has not been studied …

A Near-Global Atmospheric Distribution Of N2o Isotopologues, Peter F. Bernath, Mahdi Yousefi, Eric Buzan, Chris D. Boone

Chemistry & Biochemistry Faculty Publications

The distributions of the four most abundant isotopologues and isotopomers (N₂O, ¹⁵NNO, N¹⁵NO, and NN¹⁸O of nitrous oxide have been measured in the Earth's stratosphere by infrared remote sensing with the Atmospheric Chemistry Experiment (ACE) Fourier transform spectrometer. These satellite observations have provided a near-global picture of N₂O isotopic fractionation. The relative abundances of the heavier species increase with altitude and with latitude in the stratosphere as the air becomes older. The heavy isotopologues are enriched by 20-30% in the upper stratosphere and even more over the poles. These observations are …

Life History And Management Methods For Blueline Tilefish (Caulolatilus Microps) From The United States Mid-Atlantic Region, Michael A. Schmidtke

OES Theses and Dissertations

Blueline tilefish (Caulolatilus microps) have recently undergone an increase in landings from waters off the US Mid-Atlantic region (Virginia-Massachusetts). Currently, life history characteristics of blueline tilefish in this area are undescribed. Additionally, appropriate indices of population abundance are not available for this region, necessitating the use of data-limited management methods to set restrictions for harvest of blueline tilefish in this area. This dissertation describes growth and reproductive characteristics of blueline tilefish caught off the coast of Virginia and explores improvements of data-limited management methods that have been applied to blueline tilefish in the US Mid-Atlantic. Blueline tilefish from …

Efficient Machine Learning Approach For Optimizing Scientific Computing Applications On Emerging Hpc Architectures, Kamesh Arumugam Karunanithi

Computer Science Theses & Dissertations

Efficient parallel implementations of scientific applications on multi-core CPUs with accelerators such as GPUs and Xeon Phis is challenging. This requires - exploiting the data parallel architecture of the accelerator along with the vector pipelines of modern x86 CPU architectures, load balancing, and efficient memory transfer between different devices. It is relatively easy to meet these requirements for highly-structured scientific applications. In contrast, a number of scientific and engineering applications are unstructured. Getting performance on accelerators for these applications is extremely challenging because many of these applications employ irregular algorithms which exhibit data-dependent control-flow and irregular memory accesses. Furthermore, these …

Sensys: A Smartphone-Based Framework For Its Applications, Abdulla Ahmed Alasaadi

Computer Science Theses & Dissertations

Intelligent transportation systems (ITS) use different methods to collect and process traffic data. Conventional techniques suffer from different challenges, like the high installation and maintenance cost, connectivity and communication problems, and the limited set of data. The recent massive spread of smartphones among drivers encouraged the ITS community to use them to solve ITS challenges.

Using smartphones in ITS is gaining an increasing interest among researchers and developers. Typically, the set of sensors that comes with smartphones is utilized to develop tools and services in order to enhance safety and driving experience. GPS, cameras, Bluetooth, inertial sensors and other embedded …

Computational Modeling For Abnormal Brain Tissue Segmentation, Brain Tumor Tracking, And Grading, Syed Mohammad Shamin Reza

Electrical & Computer Engineering Theses & Dissertations

This dissertation proposes novel texture feature-based computational models for quantitative analysis of abnormal tissues in two neurological disorders: brain tumor and stroke. Brain tumors are the cells with uncontrolled growth in the brain tissues and one of the major causes of death due to cancer. On the other hand, brain strokes occur due to the sudden interruption of the blood supply which damages the normal brain tissues and frequently causes death or persistent disability. Clinical management of these brain tumors and stroke lesions critically depends on robust quantitative analysis using different imaging modalities including Magnetic Resonance (MR) and Digital Pathology …

Selenium Distribution And Cycling In The Eastern Equatorial Pacific Ocean, Zoe Wambaugh

OES Theses and Dissertations

Oxygen minimum zones in oceanic waters have become increasingly important to the marine environment and society. Low oxygen waters affect not only the distribution and abundance of marine organisms, but also impact the solubility and transport of trace elements that are of biological importance, with the chemical speciation and solubility depending on the actual redox poise of the waters. One redox sensitive trace element of interest is selenium, which can be both toxic and essential for organisms, depending on its chemical speciation. In 2013, the US GEOTRACES program completed the GP16 transect from Peru to Tahiti, going through the oxygen …

Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen

Civil & Environmental Engineering Theses & Dissertations

Water pollution is an ongoing problem that can be attributed to human activities. As world population increases and countries become more developed, this problem intensifies. Fortunately, the causes and solutions of water pollution are documented and have been implemented with various levels of success. These solutions, or Best Management Practices (BMPs), vary in type and function and remove pollutants from runoff prior to it reaching rivers, lakes, and other bodies of water. This study investigates bioretention basins, a specific group of BMPs, and presents analysis and prediction of their performance, of which our knowledge is incomplete in the existing literature. …