Digital Commons Network^™

Cloudvista: A Framework For Interactive Visual Cluster Exploration Of Big Data In The Cloud, Zhen Li

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With the development and deployment of ubiquitous information sensing, mobile devices,wireless sensor networks, RFID readers, simulation, and computer generated software logs, big data have become precious resources for scientific study, business intelligence, and national security. As one of the most intuitive and effective analysis methods,visual cluster analysis remains as a significant challenge for big datasets. First, existing visualization models need to be updated to process big data in parallel. Second, processing big data inevitably bring large latency, which conflicts the requirement of interactivity. In this thesis, we develop the CloudVista framework to address the common problems with data reduction methods …

The Construction Of A Plasmid For Detecting The Pathway Of Arginine Metabolism In Human Macrophages: A Real-Time Assessment Of Macrophage Polarity, Benjamin A. Holmes

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Macrophages are "first responders", innate immune system cells which quickly arrive to a site of infection and injury, consuming cell debris and foreign matter and recruiting other immune system cells to the area. While historically they have been thought to react uniformly to all challenges, the discovery of toll-like receptors has shown that macrophages actually work closely with the adaptive immune system in fine-tuning the immune response. Furthermore, it has recently been discovered that macrophages can become polarized to one of two subtypes-M1 or M2.

M1 macrophages are efficient producers of reactive oxygen species, nitrogen intermediates, and inflammatory cytokines. They …

Influence Of Daily Electrical Stimulation Of Periaqueductal Grey On Vocalization And Depressive-Like Behavior During Separation In Guinea Pigs, Jennifer Dazey

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Maternal separation has been shown to promote the onset of depression. This early life stressor produces a biphasic response marked by an active "protest" phase followed by a passive "despair" phase in humans as well as several other species. In infant guinea pigs, active phase behaviors include increased locomotion and species-typical distress vocalizations, whereas the passive phase is marked by depressive-like behaviors including a crouched stance, eye-closure and extensive piloerection. The mechanism underlying the transition from one phase to the next is still unknown. The purpose of this study was to determine if daily stimulation of the neural pathway initiating …

An Evaluation Of Discharge Policies At A Generic Acute Care Hospital, Elizabeth A. Crawford

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One of the main issues faced within the U.S. healthcare continuum is ineffective care transition. Ineffective transitions from one area of care to the next can lead to a reduction in quality of care, an increased risk of readmission, and an increase in healthcare costs. According to the National Transitions of Care Coalition (NTOCC), as many as 42% of the hospitals surveyed reported that care transitions during coordinated care delivery do not go as planned. One of the primary reasons for ineffective care transition is poor discharge planning. The purpose of this research is to analyze the effect of various …

Adaptive Noise Reduction Techniques For Airborne Acoustic Sensors, Ryan Michael Fuller

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Ground and marine based acoustic arrays are currently employed in a variety of military and civilian applications for the purpose of locating and identifying sources of interest. An airborne acoustic array could perform an identical role, while providing the ability to cover a larger area and pursue a target. In order to implement such a system, steps must be taken to attenuate environmental noise that interferes with the signal of interest. In this thesis, we discuss the noise sources present in an airborne environment, present currently available methods for mitigation of these sources, and propose the use of adaptive noise …

Among-Locus Heterogeneity In Genetic Diversity And Divergence In Two Pairs Of Duck Species (Genus: Anas), Kirandeep K. Dhami

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Genetic diversity and divergence at a locus are the result of interactions among the fundamental evolutionary forces of mutation, genetic drift, gene flow and natural selection. Variation in the strength of these forces can cause high heterogeneity in diversity and divergence across the genome. The overall objective of this thesis was to examine the role of population history vs. selection in generating heterogeneity in genetic diversity and differentiation. In Chapter 1, I examine the role of dispersal behavior in causing genetic differentiation and population structure within and between two morphologically distinct Australian duck species that differ in ecology and life …

Statistical Methods For Image Change Detection With Uncertainty, Andrew James Lingg

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Sensors capable of collecting wide area motion imagery (WAMI), video synthetic aperture radar (SAR), and other high frame rate sensor modalities provide massive amounts of high-resolution data. Such data allows for the use of multiple images in exploitation tasks which may have traditionally used single images or single pairs of images. One such task is change detection. This dissertation presents new statistical methods for change detection that provide for the exploitation of multiple images per pass. Uncertainty in image registration can degrade change detection performance. Registration accuracy is analyzed, and the impact of registration uncertainty is propagated to the registered …

Knowledge Acquisition In A System, Christopher J. Thomas

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I present a method for growing the amount of knowledge available on the Web using a hermeneutic method that involves background knowledge, Information Extraction techniques and validation through discourse and use of the extracted information.

I present the metaphor of the "Circle of Knowledge on the Web". In this context, knowledge acquisition on the web is seen as analogous to the way scientific disciplines gradually increase the knowledge available in their field.

Here, formal models of interest domains are created automatically or manually and then validated by implicit and explicit validation methods before the statements in the created models can …

Assessing The Drivers Of Adaptive Radiation In A Complex Of Gall Midges: A Multitrophic Perspective On Ecological Speciation, Jeremy J. Heath

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Natural enemies as selective forces maintaining and shaping morphological, physiological, and behavioral divergence in adaptive radiations have received very little attention. Until recently, the focus has been on primary resource competition as a major driver of trait divergence in adaptive radiations. Here I consider the role of natural enemies specifically in driving trait divergence in a complex of gall midges in the nominal species Asteromyia carbonifera (Diptera: Cecidomyiidae), which appears to be in the throes of an incipient adaptive radiation on its host plant, goldenrod (Solidago). This galler uses a symbiotic fungus (Botryosphaeria dothidae) as a …

Abstraction Driven Application And Data Portability In Cloud Computing, Ajith Harshana Ranabahu

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Cloud computing has changed the way organizations create, manage, and evolve their applications. While many organizations are eager to use the cloud, tempted by substantial cost savings and convenience, the implications of using clouds are still not well understood. One of the major concerns in cloud adoption is the vendor lock-in of applications, caused by the heterogeneity of the numerous cloud service offerings. Vendor locked applications are difficult, if not impossible to port from one cloud system to another, forcing cloud service consumers to use undesired or suboptimal solutions. This dissertation investigates a complete and comprehensive solution to address the …

The Next Landsat Satellite: The Landsat Data Continuity Mission, James R. Irons, John L. Dwyer, Julia A. Barsi

United States National Aeronautics and Space Administration: Publications

The National Aeronautics and Space Administration (NASA) and the Department of Interior United States Geological Survey (USGS) are developing the successor mission to Landsat 7 that is currently known as the Landsat Data Continuity Mission (LDCM). NASA is responsible for building and launching the LDCM satellite observatory. USGS is building the ground system and will assume responsibility for satellite operations and for collecting, archiving, and distributing data following launch. The observatory will consist of a spacecraft in low-Earth orbit with a two-sensor payload. One sensor, the Operational Land Imager (OLI), will collect image data for nine shortwave spectral bands over …

Continental-Scale Validation Of Modis-Based And Ledaps Landsat Etm+ Atmospheric Correction Methods, Junchang Ju, David P. Roy, Eric Vermote, Jeffrey Masek, Valeriy Kovalskyy

United States National Aeronautics and Space Administration: Publications

The potential of Landsat data processing to provide systematic continental scale products has been demonstrated by several projects including the NASA Web-enabled Landsat Data (WELD) project. The recent free availability of Landsat data increases the need for robust and efficient atmospheric correction algorithms applicable to large volume Landsat data sets. This paper compares the accuracy of two Landsat atmospheric correction methods: a MODIS-based method and the Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) method. Both methods are based on the 6SV radiative transfer code but have different atmospheric characterization approaches. The MODIS-based method uses the MODIS Terra derived dynamic aerosol …

Optimal Control Modification For Robust Adaptive Control With Large Adaptive Gain, Nhan T. Nguyen

United States National Aeronautics and Space Administration: Publications

In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to the implementation of adaptive control with a large adaptive gain so as to reduce the tracking error rapidly. However, a large adaptive gain can lead to highfrequency oscillations which can adversely affect robustness. A new adaptive law, called optimal control modification, is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations. The modification is based on a minimization of the L₂ norm of the tracking error bounded away from …

Polarimetric Retrievals Of Surface And Cirrus Clouds Properties In The Region Affected By The Deepwater Horizon Oil Spill, Matteo Ottaviani, Brian Cairns, Jacek Chowdhary, Bastiaan Van Diedenhoven, Kirk Knobelspiesse, Chris Hostetler, Rich Ferrare, Sharon Burton, John Hair, Michael D. Obland, Raymond Rogers

United States National Aeronautics and Space Administration: Publications

In 2010, the Goddard Institute for Space Studies (GISS) Research Scanning Polarimeter (RSP) performed several aerial surveys over the region affected by the oil spill caused by the explosion of the Deepwater Horizon offshore platform. The instrument was deployed on the NASA Langley B200 aircraft together with the High Spectral Resolution Lidar (HSRL), which provides information on the distribution of the aerosol layers beneath the aircraft, including an accurate estimate of aerosol optical depth.

This work illustrates the merits of polarization measurements in detecting variations of ocean surface properties linked to the presence of an oil slick. In particular, we …

Linearized T-Matrix And Mie Scattering Computations, R. Spurr, J. Wang, J. Zeng, M. I. Mishchenko

United States National Aeronautics and Space Administration: Publications

We present a new linearization of T-Matrix and Mie computations for light scattering by non-spherical and spherical particles, respectively. In addition to the usual extinc- tion and scattering cross-sections and the scattering matrix outputs, the linearized models will generate analytical derivatives of these optical properties with respect to the real and imaginary parts of the particle refractive index, and (for non-spherical scatterers) with respect to the ‘‘shape’’ parameter (the spheroid aspect ratio, cylinder diameter/height ratio, Chebyshev particle deformation factor). These derivatives are based on the essential linearity of Maxwell’s theory. Analytical derivatives are also available for polydisperse particle size distribution …

Response Of Spherical Diffusion Flames Subjected To Rotation: Microgravity Experimentation And Computational Simulation, Sean W. Yoo, Swetaprovo Chaudhuri, Kurt R. Sacksteder, Peng Zhang, Delin Zhu, Chung K. Law

United States National Aeronautics and Space Administration: Publications

Microgravity experiments were conducted in the 2.2-s drop tower and zero-gravity facility at NASA-GRC to gain fundamental understanding of the effects of spinning on an otherwise spherical diffusion flame. The flames were generated by injecting either a fuel or an oxidizer mixture from a porous burner to a controlled ambient of either an oxidizer or fuel mixture, respectively. Results show that the polar flame location scales with the angular velocity monotonically as ω^a, where a is greater and smaller than unity for small and large spinning velocities, respectively. On the contrary, the equatorial flame location responds nonmonotonically to …

Pks 2123−463: A Confirmed Γ -Ray Blazar At High Redshift, F. D’Ammando, A. Rau, P. Schady, J. Finke, M. Orienti, J. Greiner, D. A. Kann, R. Ojha, A. R. Foley, J. Stevens, J. M. Blanchard, P. G. Edwards, M. Kadler, J. E. J. Lovell

United States National Aeronautics and Space Administration: Publications

The flat spectrum radio quasar (FSRQ) PKS 2123−463 was associated in the first Fermi- Large Area Telescope (LAT) source catalogue with the γ -ray source 1FGL J2126.1−4603, but when considering the full first two years of Fermi observations, no γ -ray source at a position consistent with this FSRQ was detected, and thus PKS 2123−463 was not reported in the second Fermi-LAT source catalogue. On 2011 December 14 a γ -ray source positionally consistent with PKS 2123−463 was detected in flaring activity by Fermi-LAT. This activity triggered radio-to-X-ray observations by the Swift, Gamma-ray Optical/Near-Infrared Detector (GROND), …

Les Of Temporally Evolving Mixing Layers By An Eighth-Order Filter Scheme, Abdellah Hadjadj, Helen C. Yee, Bjorn Sjögreen

United States National Aeronautics and Space Administration: Publications

An eighth-order filter method for a wide range of compressible flow speeds (H. C. Yee and B. Sjogreen, Proceedings of ICOSAHOM09, June 22–26, 2009, Trondheim, Norway) is employed for large eddy simulations (LES) of temporally evolving mixing layers (TML) for different convective Mach numbers (M_c) and Reynolds numbers. The high-order filter method is designed for accurate and efficient simulations of shock-free compressible turbulence, turbulence with shocklets, and turbulence with strong shocks with minimum tuning of scheme parameters. The value of the M_c considered is for the TML range from the quasi-incompressible regime to the highly compressible …

Historical Perspectives On Avhrr Ndvi And Vegetation Drought Monitoring, Assaf Anyamba, Compton J. Tucker

United States National Aeronautics and Space Administration: Publications

Satellite measurements of the biosphere have now become common place in various aspects of large-scale environmental monitoring, including drought and crop monitoring. This was not the case until the launch of the Advanced Very High Resolution Radiometer (AVHRR) instrument on June 27, 1979, on board the first National Oceanic and Atmospheric Administration (NOAA) Advanced Television Infrared Observation Satellite (TIROS-N/NOAA-6) polar-orbiting satellite. Initially, the NOAA AVHRR satellites were designed to observe the earth’s weather patterns: primarily cloud dynamics, vertical soundings of the atmosphere, and sea surface temperatures. Early studies on remote sensing of vegetation were focused on understanding seasonality. The vernal …

Satellite Gravimetry Applied To Drought Monitoring, Matthew Rodell

United States National Aeronautics and Space Administration: Publications

11.1 Introduction...261

11.2 Satellite Gravimetry...262

11.3 Gravity Recovery and Climate Experiment...263

11.4 Hydrological Science Enabled by GRACE...264

11.5 Unique and Challenging Aspects of GRACE Data...265

11.6 Disaggregating and Downscaling GRACE Data...266

11.7 Drought Monitoring with GRACE...268

11.8 Future Prospects... 272

Acknowledgments....274

References.... 274

Les Of Temporally Evolving Mixing Layers By An Eighth-Order Filter Scheme, Abdellah Hadjadj, Helen Yee, Bjorn Sjögreen

United States National Aeronautics and Space Administration: Publications

An eighth-order filter method for a wide range of compressible flow speeds (H. C. Yee and B. Sjogreen, Proceedings of ICOSAHOM09, June 22–26, 2009, Trondheim, Norway) is employed for large eddy simulations (LES) of temporally evolving mixing layers (TML) for different convective Mach numbers (M_c) and Reynolds numbers. The high-order filter method is designed for accurate and efficient simulations of shock-free compressible turbulence, turbulence with shocklets, and turbulence with strong shocks with minimum tuning of scheme parameters. The value of the M_c considered is for the TML range from the quasi-incompressible regime to the highly compressible …

Comparative Study Of High-Order Positivity-Preserving Weno Schemes, D. V. Kotov, Helen C. Yee, Bjorn Sjögreen

United States National Aeronautics and Space Administration: Publications

In gas dynamics and magnetohydrodynamics flows, physically, the density ρ and the pressure p should both be positive. In a standard conservative numerical scheme, however, the computed internal energy is obtained by subtracting the kinetic energy from the total energy, resulting in a computed p that may be negative. Examples are problems in which the dominant energy is kinetic. Negative ρ may often emerge in computing blast waves. In such situations the computed eigenvalues of the Jacobian will become imaginary. Consequently, the initial value problem for the linearized system will be ill posed. This explains why failure of preserving positivity …

Trading Resistance For Vigor: A Potential Mechanism For Invasion By The Asian Grass Microstegium Vimineum, Matthew Dickinson

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The Evolution of Increased Competitive Ability (EICA) hypothesis predicts that subsequent to introduction, non-native plants escape enemies and selection favors genotypes that invest more in growth and reproduction and less in resistance. Here, I evaluated if the invasive Asian grass Microstegium vimineum has developed decreased resistance in its introduced range of the eastern US, as predicted by the EICA hypothesis. Asian and US genotypes were evaluated for differences in enemy damage, leaf toughness, specific leaf area (SLA), and flowering in a common garden experiment. Leaf damage, SLA, and flower production were greater and leaf toughness lower in US plants. These …

Regulation Of Mitosis By Nuclear Speckle Proteins, Keshia Nicole Torres-Munoz

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Mitosis is an intricate process that is monitored by multiple cell cycle regulator proteins. Errors in mitotic regulation have been linked to many types of cancer. Recently, evidence suggests an indirect regulation of mitosis by nuclear speckle proteins. Nuclear speckles are one of the multiple compartments found in the mammalian cell nucleus. They serve as assembly compartments for premRNA processing factors. Mass spectrometry analysis of purified nuclear speckles revealed 33 novel proteins including Son and TRAP150. The aim of my study was to determine how Son and TRAP150 can directly or indirectly impact mitosis. We and others recently reported that …

A Sers And Sem-Edx Study Of The Antiviral Mechanism Of Creighton Silver Nanoparticles Against Vaccinia Virus, Catherine Binns Anders

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Silver nanoparticles (AgNPs) are well-recognized as antiviral agents but little is known about their mechanism of action. In this study, it was hypothesized that unfunctionalized, Creighton AgNPs of an average diameter of 11 nm will form covalent bonds with vaccinia virus (VV) mainly through the external, entry fusion complex (EFC) proteins. The EFC is housed on the external membrane of VV and contains 9-12 proteins having numerous cysteine groups, intramolecular disulfide bonds, aromatic moieties and myristic acids bound to the N-terminus of glycine residues. VV (1012 PFUs) was incubated at 37oC for one hour with Creighton AgNPs that were size …

Application Of Auto-Tracking To The Study Of Insect Body Kinematics In Maneuver Flight, Shreyas Vathul Subramanian

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There is a need to explain the complex phenomena that underlies the seemingly effortless flight modes of the dragonfly (Infra -order Anisoptera). However, measuring the body kinematics during flight is labor intensive. Thus a robust system was developed that automatically tracks and quantifies the body kinematics of a dragonfly during voluntary and escape take-offs, as well as maneuvers. Ultimately, the tool, which was developed using a custom code in C++ using the open source library OpenCV (Open Computer Vision), would be used to analyze bulk samples of high speed videos providing raw images at the rate of approximately 1000 frames …

On The Quantization Problem In Curved Space, Benjamin Bernard

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The nonrelativistic quantum mechanics of particles constrained to curved surfaces is studied. There is open debate as to which of several approaches is the correct one. After a review of existing literature and the required mathematics, three approaches are studied and applied to a sphere, spheroid, and triaxial ellipsoid.

The first approach uses differential geometry to reduce the problem from a three dimensional problem to a two-dimensional problem. The second approach uses three dimensions and holds one of the separated wavefunctions and its associated coordinate constant. A third approach constrains the particle in a three-dimensional space between two parallel surfaces …

Extension Of Polar Format Scene Size Limits To Squinted Geometries, Matthew Steven Horvath

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The Polar Format Algorithm (PFA) is an often used algorithm to image synthetic aperture radar (SAR) phase history data. The algorithm relies on a far-field approximation wherein the curved wavefront of the transmitted pulses is approximated as a planar wavefront, introducing spatially variant phase errors in the phase history. While allowing for faster image formation compared to more exact imaging algorithms such as convolution backprojection, these phase errors lead to the distortion and defocus of point targets, degrading the quality of the resulting imaged scene.

Historically, a Taylor expansion has been used to approximate the phase errors leading to distortion …

A Mechanism-Based Model To Describe Gabaa Receptor Trafficking And Benzodiazepine Pharmacoresistance During Status Epilepticus, Elaine Alice Merrill

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Status epilepticus (SE) is a perplexing pathology involving a sudden and long disruption of the brain's normal electrical activity. The study of relevant cellular processes has been useful in identifying therapeutic targets. As a result, many novel drugs are being studied which target receptor systems involved in neuronal membrane excitability. Yet, the standard treatment for SE remains benzodiazepines (BZs), a class of GABAA agonist drugs. Unfortunately, the targeted receptors undergo a desensitization mechanism via enhanced endocytosis (receptor trafficking), leading to rapidly reduced BZ efficacy (pharmacoresistance) within minutes of seizure onset. A comprehensive understanding of the complex interplay between the anticonvulsant's …

Winding Resistance And Winding Power Loss Of High-Frequency Power Inductors, Rafal P. Wojda

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The scope of this research is concentrated on analytical winding size optimization (thickness or diameter) of high-frequency power inductors wound with foil, solid-round wire, multi-strand wire, and litz-wire conductors.

The first part of this research concerns analytical optimization of the winding size (thickness or diameter) for the inductors conducting a sinusoidal current. Estimation of winding resistance in individual inductor layers made of foil, taking into account the skin and proximity effects is performed. Approximated equations for the winding power loss in each layer are given and the optimal values of foil thickness for each layer are derived.

A low- and …