CyanoGEBA: A Better Understanding of Cynobacterial Diversity through Large-Scale Genomics (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Shih, Patrick

2018-01-10

Patrick Shih, representing both the University of California, Berkeley and JGI, gives a talk titled "CyanoGEBA: A Better Understanding of Cynobacterial Diversity through Large-scale Genomics" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Next-Generation Genetics in Plants: Evolutionary Trade-off, Immunity and Speciation (2010 JGI User Meeting)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiegel, Detlef

Detlef Wiegel from the Max Planck Institute for Developmental Biology on "Next-generation genetics in plants: Evolutionary tradeoffs, immunity and speciation" on March 25, 2010 at the 5th Annual DOE JGI User Meeting.

Next-Generation Genetics in Plants: Evolutionary Trade-off, Immunity and Speciation (2010 JGI User Meeting)

ScienceCinema

Wiegel, Detlef

2018-02-12

Detlef Wiegel from the Max Planck Institute for Developmental Biology on "Next-generation genetics in plants: Evolutionary tradeoffs, immunity and speciation" on March 25, 2010 at the 5th Annual DOE JGI User Meeting.

Keynote Presentation: Genome Beat (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Zimmer, Carl [New York Times, New York, NY (United States)

2018-05-23

Carl Zimmer, a reporter for the New York Times, speaks on "The Genome Beat," the opening keynote presentation at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Keynote Presentation: Genome Beat (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zimmer, Carl

Carl Zimmer, a reporter for the New York Times, speaks on "The Genome Beat," the opening keynote presentation at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Competitiveness of Second Generation Biofuel Feedstocks: Role of Technology and Policy (2010 JGI User Meeting)

ScienceCinema

Khanna, Madhu

2018-02-19

Madhu Khanna from the University of Illinois at Urbana-Champaign and the Energy Biosciences Institute on Competitiveness of Second Generation Biofuel Feedstocks: Role of Technology and Policy on March 25, 2010 at the 5th Annual DOE JGI User Meeting.

The Promise and Challenge of Producing Biofuel Feedstocks: An Ecological Perspective (2010 JGI User Meeting)

ScienceCinema

DeLucia, Evan

2018-02-13

Evan DeLucia of the University of Illinois at Urbana-Champaign and the Energy Biosciences Institute talks about The Promise and Challenge of Producing Biofuel Feedstocks: An Ecological Perspective on March 25, 2010 at the 5th Annual DOE JGI User Meeting.

Association Genetics of Populus trichocarpa or Resequencing in Populus: Towards Genome Wide Association Genetics (2011 JGI User Meeting)

ScienceCinema

Tuskan, Gerry

2018-02-13

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Gerry Tuskan of Oak Ridge National Laboratory on Resequencing in Populus: Towards Genome Wide Association Genetics at the 6th annual Genomics of Energy Environment Meeting on March 23, 2011.

The Laccaria and Tuber Genomes Reveal Unique Signatures of Mycorrhizal Symbiosis Evolution (2010 JGI User Meeting)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, Francis

Francis Martin from the French National Institute for Agricultural Research (INRA) talks on how "The Laccaria and Tuber genomes reveal unique signatures of mycorrhizal symbiosis evolution" on March 24, 2010 at the 5th Annual DOE JGI User Meeting

Association Genetics of Populus trichocarpa or Resequencing in Populus: Towards Genome Wide Association Genetics (2011 JGI User Meeting)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuskan, Gerry

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Gerry Tuskan of Oak Ridge National Laboratory on Resequencing in Populus: Towards Genome Wide Association Geneticsmore » at the 6th annual Genomics of Energy Environment Meeting on March 23, 2011.« less

Using Genomics to Dissect Seed Development (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment Meeting)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldberg, Robert

2012-03-21

Robert Goldberg of UCLA presents "Using Genomics to Dissect Seed Development" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Using Genomics to Dissect Seed Development (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment Meeting)

ScienceCinema

Goldberg, Robert

2018-04-27

Robert Goldberg of UCLA presents "Using Genomics to Dissect Seed Development" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Comparative Metagenomics of Gut and Ocean: Identification of Microbial Marker Genes for Complex Environmental Properties (2011 JGI User Meeting)

ScienceCinema

Bork, Peer

2018-02-14

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Peer Bork of the European Molecular Biology Laboratory on Comparative Metagenomics of Gut and Ocean: Identification of Microbial Marker Genes for Complex Environmental Properties at the 6th annual Genomics of Energy & Environment Meeting on March 23, 2011.

Genomics on the Half Shell: So, What do Oysters Have to do with Energy? (2010 JGI User Meeting)

ScienceCinema

Hedgecock, Dennis

2018-04-26

Dennis Hedgecock from the University of Southern California answers the question, "Genomics on the Half Shell: So, What Do Oysters Have to Do with Energy?" on March 24, 2010 at the 5th Annual DOE JGI User Meeting.

Regulatory Networks Controlling Plant Cold Acclimation or Low Temperature Regulatory Networks Controlling Cold Acclimation in Arabidopsis (2011 JGI User Meeting)

ScienceCinema

Thomashow, Mike

2018-02-06

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Mike Thomashow of Michigan State University gives a presentation on on "Low Temperature Regulatory Networks Controlling Cold Acclimation in Arabidopsis" at the 6th annual Genomics of Energy & Environment Meeting on March 23, 2011."

New Challenges of the Computation of Multiple Sequence Alignments in the High-Throughput Era (2010 JGI/ANL HPC Workshop)

ScienceCinema

Notredame, Cedric

2018-05-02

Cedric Notredame from the Centre for Genomic Regulation gives a presentation on New Challenges of the Computation of Multiple Sequence Alignments in the High-Throughput Era at the JGI/Argonne HPC Workshop on January 26, 2010.

Reprogramming Bacteria to Seek and Destroy Small Molecules (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallivan, Justin

2012-03-21

Justin Gallivan, of Emory University presents a talk titled "Reprogramming Bacteria to Seek and Destroy Small Molecules" at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 21, 2012 in Walnut Creek, CA.

Reprogramming Bacteria to Seek and Destroy Small Molecules (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Gallivan, Justin

2018-05-01

Justin Gallivan, of Emory University presents a talk titled "Reprogramming Bacteria to Seek and Destroy Small Molecules" at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 21, 2012 in Walnut Creek, CA.

Host Genetic Control of the Microbiome in Humans and Maize or Relating Host Genetic Variation to the Microbiome (2011 JGI User Meeting)

ScienceCinema

Ley, Ruth E. [Cornell Univ., Ithaca, NY (United States). Cornell Center for Comparative and Population Genomics, Dept. of Microbiology and Dept. of Molecular Biology and Genetics

2018-06-27

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy and Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Ruth Ley of Cornell University gives a presentation on "Relating Host Genetic Variation to the Microbiome" at the 6th annual Genomics of Energy and Environment Meeting on March 23, 2011.

Introduction to Metagenomics at DOE JGI: Program Overview and Program Informatics (Metagenomics Informatics Challenges Workshop: 10K Genomes at a Time)

ScienceCinema

Tringe, Susannah

2018-01-15

Susannah Tringe of the DOE Joint Genome Institute talks about the Program Overview and Program Informatics at the Metagenomics Informatics Challenges Workshop held at the DOE JGI on October 12-13, 2011.

Host Genetic Control of the Microbiome in Humans and Maise or Relating Host Genetic Variation to the Microbiome (2011 JGI User Meeting)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ley, Ruth

2011-03-23

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Ruth Ley of Cornell University gives a presentation on "Relating Host Genetic Variation to themore » Microbiome" at the 6th annual Genomics of Energy & Environment Meeting on March 23, 2011.« less

Tapping the Molecular Potential of Microalgae to Produce Biomass (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Sayre, Richard; Kyrpides, Nikos

2018-05-03

Richard Sayre, from Los Alamos National Laboratory, presents a talk titled "Tapping the Molecular Potential of Microalgae to Produce Biomass" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Getting to the Root of Things: Spatiotemporal Regulatory Networks (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Brady, Siobhan

2018-02-12

Siobhan Brady from University of California, Davis, gives a talk titled "Getting to the Root of things: Spatiotemporal Regulatory Networks" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Getting to the Root of Things: Spatiotemporal Regulatory Networks (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brady, Siobhan

2012-03-22

Siobhan Brady from University of California, Davis, gives a talk titled "Getting to the Root of things: Spatiotemporal Regulatory Networks" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Tapping the Molecular Potential of Microalgae to Produce Biomass (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sayre, Richard; Kyrpides, Nikos

2012-03-22

Richard Sayre, from Los Alamos National Laboratory, presents a talk titled "Tapping the Molecular Potential of Microalgae to Produce Biomass" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Genomic and Systems Biology Analyses of Social Behavior or Evolutionary Genomic Analyses of Insect Society: Eat, Drink, and Be Scary (2011 JGI User Meeting)

ScienceCinema

Robinson, Gene

2018-02-05

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, CA. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Gene Robinson of the University of Illinois on Genomic and Systems Biology Analyses of Social Behavior at the 6th Annual Genomics of Energy & Environment Meeting on March 23, 2011.

Nonlinear Eddy-Eddy Interactions in Dry Atmospheres Macroturbulence

NASA Astrophysics Data System (ADS)

Ait Chaalal, F.; Schneider, T.

2012-12-01

The statistical moment equations derived from the atmospheric equation of motions are not closed. However neglecting the large-scale eddy-eddy nonlinear interactions in an idealized dry general circulation model (GCM), which is equivalent to truncating the moment equations at the second order, can reproduce some of the features of the general circulation ([1]), highlighting the significance of eddy-mean flow interactions and the weakness of eddy-eddy interactions in atmospheric macroturbulence ([2]). The goal of the present study is to provide new insight into the rôle of these eddy-eddy interactions and discuss the relevance of a simple stochastic parametrization to represent them. We investigate in detail the general circulation in an idealized dry GCM, comparing full simulations with simulations where the eddy-eddy interactions are removed. The radiative processes are parametrized through Newtonian relaxation toward a radiative-equilibrium state with a prescribed equator to pole temperature contrast. A convection scheme relaxing toward a prescribed convective vertical lapse rate mimics some aspects of moist convection. The study is performed over a wide range of parameters covering the planetary rotation rate, the equator to pole temperature contrast and the vertical lapse rate. Particular attention is given to the wave-mean flow interactions and to the spectral budget. It is found that the no eddy-eddy simulations perform well when the baroclinic activity is weaker, for example for lower equator to pole temperature contrasts or higher rotation rates: the mean meridional circulation is well reproduced, with realistic eddy-driven jets and energy-containing eddy length scales of the order of the Rossby deformation radius. For a stronger baroclinic activity the no eddy-eddy model does not achieve a realistic isotropization of the eddies, the meridional circulation is compressed in the meridional direction and secondary eddy-driven jets emerge. In addition, the

Genome-Scale Discovery of Cell Wall Biosynthesis Genes in Populus (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Muchero, Wellington

2018-01-15

Wellington Muchero from Oak Ridge National Laboratory gives a talk titled "Discovery of Cell Wall Biosynthesis Genes in Populus" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Genomic and Systems Biology Analyses of Social Behavior or Evolutionary Genomic Analyses of Insect Society: Eat, Drink, and Be Scary (2011 JGI User Meeting)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robinson, Gene

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, CA. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Gene Robinson of the University of Illinois on Genomic and Systems Biology Analyses of Socialmore » Behavior at the 6th Annual Genomics of Energy & Environment Meeting on March 23, 2011.« less

Closing Keynote Presentation on the Genomics of Energy and the Environment (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Benner, Steve

2018-05-08

Steve Benner, a distinguished chemist at the Foundation for Applied Molecular Evolution, Westheimer Institute of Science and Technology, provides the closing keynote address for the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

Closing Keynote Presentation on the Genomics of Energy and the Environment (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benner, Steve

2012-03-22

Steve Benner, a distinguished chemist at the Foundation for Applied Molecular Evolution, Westheimer Institute of Science and Technology, provides the closing keynote address for the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

The standard operating procedure of the DOE-JGI Microbial Genome Annotation Pipeline (MGAP v.4).

PubMed

Huntemann, Marcel; Ivanova, Natalia N; Mavromatis, Konstantinos; Tripp, H James; Paez-Espino, David; Palaniappan, Krishnaveni; Szeto, Ernest; Pillay, Manoj; Chen, I-Min A; Pati, Amrita; Nielsen, Torben; Markowitz, Victor M; Kyrpides, Nikos C

2015-01-01

The DOE-JGI Microbial Genome Annotation Pipeline performs structural and functional annotation of microbial genomes that are further included into the Integrated Microbial Genome comparative analysis system. MGAP is applied to assembled nucleotide sequence datasets that are provided via the IMG submission site. Dataset submission for annotation first requires project and associated metadata description in GOLD. The MGAP sequence data processing consists of feature prediction including identification of protein-coding genes, non-coding RNAs and regulatory RNA features, as well as CRISPR elements. Structural annotation is followed by assignment of protein product names and functions.

Systems Biology Approaches to Dissecting Plant Cell Wall Biosynthesis Genes in Poplus (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Glass, N. Louise; Pennacchio, Len

2018-02-13

N. Louise Glass from the University of California, Berkeley, presents a talk titled "Systems Biology Approaches to Dissecting Plant Cell Wall Biosynthesis Genes in Poplus" at the JGI 7th Annual Users Meeting: Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, California.

The standard operating procedure of the DOE-JGI Microbial Genome Annotation Pipeline (MGAP v.4)

DOE PAGES

Huntemann, Marcel; Ivanova, Natalia N.; Mavromatis, Konstantinos; ...

2015-10-26

The DOE-JGI Microbial Genome Annotation Pipeline performs structural and functional annotation of microbial genomes that are further included into the Integrated Microbial Genome comparative analysis system. MGAP is applied to assembled nucleotide sequence datasets that are provided via the IMG submission site. Dataset submission for annotation first requires project and associated metadata description in GOLD. The MGAP sequence data processing consists of feature prediction including identification of protein-coding genes, non-coding RNAs and regulatory RNA features, as well as CRISPR elements. In conclusion, structural annotation is followed by assignment of protein product names and functions.

The standard operating procedure of the DOE-JGI Microbial Genome Annotation Pipeline (MGAP v.4)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huntemann, Marcel; Ivanova, Natalia N.; Mavromatis, Konstantinos

The DOE-JGI Microbial Genome Annotation Pipeline performs structural and functional annotation of microbial genomes that are further included into the Integrated Microbial Genome comparative analysis system. MGAP is applied to assembled nucleotide sequence datasets that are provided via the IMG submission site. Dataset submission for annotation first requires project and associated metadata description in GOLD. The MGAP sequence data processing consists of feature prediction including identification of protein-coding genes, non-coding RNAs and regulatory RNA features, as well as CRISPR elements. In conclusion, structural annotation is followed by assignment of protein product names and functions.

The Depth Limits of Eddy Current Testing for Defects: A Computational Investigation and Smooth-Shaped Defect Synthesis from Finite Element Optimization

DTIC Science & Technology

2015-04-22

AND SUBTITLE 5a. CONTRACT NUMBER W56HZV-07-2-0001 W56HZV-08- C - 0236 The Depth Limits of Eddy Current Testing for Defects: A...Unlimited b. ABSTRACT Unlimited c . THIS PAGE Unlimited Unlimited 12 19b. TELEPHONE NUMBER (include area code) 586-282-6471 Standard Form 298...Dave Gunter, Acting Associate Director, Analytics, US Army TARDEC  Dr. Dave Horner, Director, DoD HPC Mod Program  Mr. Steve Knott , Deputy

In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

ScienceCinema

Mosier, Annika

2018-01-22

Annika Mosier, graduate student from Stanford University presents a talk titled "In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi" at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, CA.

Metabolic Noise, Vestigial Metabolites or the Raw Material of Ecological Adaptation? Opportunitistic Enzymes, Catalytic Promiscuity and the Evolution of Chemodiversity in Nature (2010 JGI User Meeting)

ScienceCinema

Noel, Joseph

2018-04-26

Joseph Noel from the Salk Institute on "Metabolic Noise, Vestigial Metabolites or the Raw Material of Ecological Adaptation? Enzymes, Catalytic Promiscuity and the Evolution of Chemodiversity in Nature" on March 26, 2010 at the 5th Annual DOE JGI User Meeting.

Ingredients of the Eddy Soup: A Geometric Decomposition of Eddy-Mean Flow Interactions

NASA Astrophysics Data System (ADS)

Waterman, S.; Lilly, J. M.

2014-12-01

Understanding eddy-mean flow interactions is a long-standing problem in geophysical fluid dynamics with modern relevance to the task of representing eddy effects in coarse resolution models while preserving their dependence on the underlying dynamics of the flow field. Exploiting the recognition that the velocity covariance matrix/eddy stress tensor that describes eddy fluxes, also encodes information about eddy size, shape and orientation through its geometric representation in the form of the so-called variance ellipse, suggests a potentially fruitful way forward. Here we present a new framework that describes eddy-mean flow interactions in terms of a geometric description of the eddy motion, and illustrate it with an application to an unstable jet. Specifically we show that the eddy vorticity flux divergence F, a key dynamical quantity describing the average effect of fluctuations on the time-mean flow, may be decomposed into two components with distinct geometric interpretations: 1. variations in variance ellipse orientation; and 2. variations in the anisotropic part of the eddy kinetic energy, a function of the variance ellipse size and shape. Application of the divergence theorem shows that F integrated over a region is explained entirely by variations in these two quantities around the region's periphery. This framework has the potential to offer new insights into eddy-mean flow interactions in a number of ways. It identifies the ingredients of the eddy motion that have a mean flow forcing effect, it links eddy effects to spatial patterns of variance ellipse geometry that can suggest the mechanisms underpinning these effects, and finally it illustrates the importance of resolving eddy shape and orientation, and not just eddy size/energy, to accurately represent eddy feedback effects. These concepts will be both discussed and illustrated.

An avenue of eddies: Quantifying the biophysical properties of mesoscale eddies in the Tasman Sea

NASA Astrophysics Data System (ADS)

Everett, J. D.; Baird, M. E.; Oke, P. R.; Suthers, I. M.

2012-08-01

The Tasman Sea is unique - characterised by a strong seasonal western boundary current that breaks down into a complicated field of mesoscale eddies almost immediately after separating from the coast. Through a 16-year analysis of Tasman Sea eddies, we identify a region along the southeast Australian coast which we name ‘Eddy Avenue’ where eddies have higher sea level anomalies, faster rotation and greater sea surface temperature and chlorophyll a anomalies. The density of cyclonic and anticyclonic eddies within Eddy Avenue is 23% and 16% higher respectively than the broader Tasman Sea. We find that Eddy Avenue cyclonic and anticyclonic eddies have more strongly differentiated biological properties than those of the broader Tasman Sea, as a result of larger anticyclonic eddies formed from Coral Sea water depressing chl. a concentrations, and for coastal cyclonic eddies due to the entrainment of nutrient-rich shelf waters. Cyclonic eddies within Eddy Avenue have almost double the chlorophyll a (0.35 mg m-3) of anticyclonic eddies (0.18 mg m-3). The average chlorophyll a concentration for cyclonic eddies is 16% higher in Eddy Avenue and 28% lower for anticyclonic eddies when compared to the Tasman Sea. With a strengthening East Australian Current, the propagation of these eddies will have significant implications for heat transport and the entrainment and connectivity of plankton and larval fish populations.

Southern Ocean eddy compensation in a forced eddy-resolving GCM

NASA Astrophysics Data System (ADS)

Bruun Poulsen, Mads; Jochum, Markus; Eden, Carsten; Nuterman, Roman

2017-04-01

Contemporary eddy-resolving model studies have demonstrated that the common parameterisation of isopycnal mixing in the ocean is subject to limitations in the Southern Ocean where the mesoscale eddies are of leading order importance to the dynamics. We here present forced simulations from the Community Earth System Model on a global {1/10}° and 1° horizontal grid, the latter employing an eddy parameterisation, where the strength of the zonal wind stress south of 25°S has been varied. With a 50% zonally symmetric increase of the wind stress, we show that the two models arrive at two radically different solutions in terms of the large-scale circulation, with an increase of the deep inflow of water to the Southern Ocean at 40°S by 50% in the high resolution model against 20% at coarse resolution. Together with a weaker vertical displacement of the pycnocline in the 1° model, these results suggest that the parameterised eddies have an overly strong compensating effect on the water mass transformation compared to the explicit eddies. Implications for eddy mixing parameterisations will be discussed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stacey, Gary

Gary Stacey, associate director of the National Center for Soybean Biotechnology at the University of Missouri, gives a talk simply titled "Soybean" on March 24, 2010 at the 5th Annual DOE JGI User Meeting.

The standard operating procedure of the DOE-JGI Metagenome Annotation Pipeline (MAP v.4)

DOE PAGES

Huntemann, Marcel; Ivanova, Natalia N.; Mavromatis, Konstantinos; ...

2016-02-24

The DOE-JGI Metagenome Annotation Pipeline (MAP v.4) performs structural and functional annotation for metagenomic sequences that are submitted to the Integrated Microbial Genomes with Microbiomes (IMG/M) system for comparative analysis. The pipeline runs on nucleotide sequences provide d via the IMG submission site. Users must first define their analysis projects in GOLD and then submit the associated sequence datasets consisting of scaffolds/contigs with optional coverage information and/or unassembled reads in fasta and fastq file formats. The MAP processing consists of feature prediction including identification of protein-coding genes, non-coding RNAs and regulatory RNAs, as well as CRISPR elements. Structural annotation ismore » followed by functional annotation including assignment of protein product names and connection to various protein family databases.« less

The standard operating procedure of the DOE-JGI Metagenome Annotation Pipeline (MAP v.4)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huntemann, Marcel; Ivanova, Natalia N.; Mavromatis, Konstantinos

The DOE-JGI Metagenome Annotation Pipeline (MAP v.4) performs structural and functional annotation for metagenomic sequences that are submitted to the Integrated Microbial Genomes with Microbiomes (IMG/M) system for comparative analysis. The pipeline runs on nucleotide sequences provide d via the IMG submission site. Users must first define their analysis projects in GOLD and then submit the associated sequence datasets consisting of scaffolds/contigs with optional coverage information and/or unassembled reads in fasta and fastq file formats. The MAP processing consists of feature prediction including identification of protein-coding genes, non-coding RNAs and regulatory RNAs, as well as CRISPR elements. Structural annotation ismore » followed by functional annotation including assignment of protein product names and connection to various protein family databases.« less

Mesoscale Eddies in the Northwestern Pacific Ocean: Three-Dimensional Eddy Structures and Heat/Salt Transports

NASA Astrophysics Data System (ADS)

Dong, Di; Brandt, Peter; Chang, Ping; Schütte, Florian; Yang, Xiaofeng; Yan, Jinhui; Zeng, Jisheng

2017-12-01

The region encompassing the Kuroshio Extension (KE) in the Northwestern Pacific Ocean (25°N-45°N and 130°E-180°E) is one of the most eddy-energetic regions of the global ocean. The three-dimensional structures and transports of mesoscale eddies in this region are comprehensively investigated by combined use of satellite data and Argo profiles. With the allocation of Argo profiles inside detected eddies, the spatial variations of structures of eddy temperature and salinity anomalies are analyzed. The results show that eddies predominantly have subsurface (near-surface) intensified temperature and salinity anomalies south (north) of the KE jet, which is related to different background stratifications between these regions. A new method based on eddy trajectories and the inferred three-dimensional eddy structures is proposed to estimate heat and salt transports by eddy movements in a Lagrangian framework. Spatial distributions of eddy transports are presented over the vicinity of the KE for the first time. The magnitude of eddy-induced meridional heat (freshwater volume) transport is on the order of 0.01 PW (103 m3/s). The eddy heat transport divergence results in an oceanic heat loss south and heat gain north of the KE, thereby reinforcing and counteracting the oceanic heat loss from air-sea fluxes south and north of the KE jet, respectively. It also suggests a poleward heat transport across the KE jet due to eddy propagation.

The Stability of Outcropping Ocean Eddies

NASA Astrophysics Data System (ADS)

Paldor, N.; Cohen, Y.; Dvorkin, Y.

2017-12-01

In the end of the last century numerous ship-borne observations and linear instability studies have addressed the long life span of meso-scale ocean eddies. These eddies are observed to persist in the ocean for periods of 2-3 years with little deformation. As eddy instabilities occur because Rossby waves in the surrounding (assumed motionless) ocean interact with various waves in the eddy itself, the stability was attributed to some eddy structure that hinders such wave-wave interactions. However, instabilities with growthrates of the order of the inertial period were found in various multilayer models including hypothesized structures and several observed eddy structures. A solution to the difference between instability theory and observed stability was ultimately suggested by relaxing the assumption of a motionless ocean that surrounds the eddy and prescribing the mean flow in the ocean such that it counterbalances the depth changes imposed by the eddy while maintaining a constant PV-ocean. This hypothesis was successfully applied to Gaussian eddies for mathematical simplicity. Yet, the Gaussian eddy has no surface front - thus avoiding instabilities that involve frontal waves - and it disagrees with observation that clearly show that most eddies have surface fronts. Here the constant PV ocean hypothesis is applied to two frontal eddies: constant PV-eddies and solidly rotating eddy. A complete account of the mean flow of the coupled eddy-ocean system is analyzed using a canonical formulation of the gradient balance. The phase speeds of waves in the eddy-ocean system are computed by a shooting method. Both eddies are found to be unstable in motionless ocean, yet in a constant PV-ocean no instabilities are found using the exact same numerical search. While many eddy structures can be hypothesized there are only a handful of physical mechanisms for instability and in these eddies the assumed constant PV-ocean negates many of these physical mechanisms for instability

Effects of Eddy Viscosity on Time Correlations in Large Eddy Simulation

NASA Technical Reports Server (NTRS)

He, Guowei; Rubinstein, R.; Wang, Lian-Ping; Bushnell, Dennis M. (Technical Monitor)

2001-01-01

Subgrid-scale (SGS) models for large. eddy simulation (LES) have generally been evaluated by their ability to predict single-time statistics of turbulent flows such as kinetic energy and Reynolds stresses. Recent application- of large eddy simulation to the evaluation of sound sources in turbulent flows, a problem in which time, correlations determine the frequency distribution of acoustic radiation, suggest that subgrid models should also be evaluated by their ability to predict time correlations in turbulent flows. This paper compares the two-point, two-time Eulerian velocity correlation evaluated from direct numerical simulation (DNS) with that evaluated from LES, using a spectral eddy viscosity, for isotropic homogeneous turbulence. It is found that the LES fields are too coherent, in the sense that their time correlations decay more slowly than the corresponding time. correlations in the DNS fields. This observation is confirmed by theoretical estimates of time correlations using the Taylor expansion technique. Tile reason for the slower decay is that the eddy viscosity does not include the random backscatter, which decorrelates fluid motion at large scales. An effective eddy viscosity associated with time correlations is formulated, to which the eddy viscosity associated with energy transfer is a leading order approximation.

Obituary: John Allen Eddy (1931-2009)

NASA Astrophysics Data System (ADS)

Gingerich, Owen

2011-12-01

bin HAD," which has been passed on to every subsequent division president. At the IAU meeting in New Delhi, Eddy became president of the IAU Commission 41 on the history of astronomy (1985-88). While at the CfA Eddy received a tenure offer from the director, George Field. But Eddy's wife, Marjorie Bratt Eddy, and four children had remained behind, and Jack felt obliged to return to Colorado. With the offer from the Smithsonian Observatory and his considerable fame, HAO and NCAR were eager to rehire him. Eddy soon became increasingly interested in interdisciplinary sciences, turning away from his earlier enthusiasm for the history of astronomy. He became the first chairman of a National Academy of Sciences committee for an International Geosphere-Biosphere Program, which later became the U.S. Global Change Program. Early in 1986, UCAR (the University Corporation for Atmospheric research, which managed NCAR) formalized its response to the challenge of global change with a new Office for Interdisciplinary Earth Studies, which Eddy founded and directed. The office focused efforts to bring the atmospheric sciences and other relevant disciplines together to study the earth's living and inanimate elements as a single system. In 1987 Eddy received the Arctowski medal from the National Academy of Science, an honor awarded triennially for studies in solar physics and solar terrestrial relationships. In 1992 Eddy found a new opportunity as chief scientist and vice president of the Center for International Earth Science Information Network, which he described as a federally funded pork barrel project in Michigan. Meanwhile Eddy had divorced; he remarried in 1992 to a fellow worker at UCAR, and he and his new wife, Barbara, relocated to Saginaw, Michigan. After two years he was "extremely frustrated" by the bureaucracy, so he and Barbara struck out on their own, founding the newsletter Consequences (with support from five federal agencies) to explain in popular terms the nature

Anticyclonic eddies are more productive than cyclonic eddies in subtropical gyres because of winter mixing.

PubMed

Dufois, François; Hardman-Mountford, Nick J; Greenwood, Jim; Richardson, Anthony J; Feng, Ming; Matear, Richard J

2016-05-01

Mesoscale eddies are ubiquitous features of ocean circulation that modulate the supply of nutrients to the upper sunlit ocean, influencing the rates of carbon fixation and export. The popular eddy-pumping paradigm implies that nutrient fluxes are enhanced in cyclonic eddies because of upwelling inside the eddy, leading to higher phytoplankton production. We show that this view does not hold for a substantial portion of eddies within oceanic subtropical gyres, the largest ecosystems in the ocean. Using space-based measurements and a global biogeochemical model, we demonstrate that during winter when subtropical eddies are most productive, there is increased chlorophyll in anticyclones compared with cyclones in all subtropical gyres (by 3.6 to 16.7% for the five basins). The model suggests that this is a consequence of the modulation of winter mixing by eddies. These results establish a new paradigm for anticyclonic eddies in subtropical gyres and could have important implications for the biological carbon pump and the global carbon cycle.

The eddy cannon

NASA Astrophysics Data System (ADS)

Pichevin, Thierry; Nof, Doron

1996-09-01

A new nonlinear mechanism for the generation of "Meddies" by a cape is proposed. The essence of the new process is that the flow-force associated with any steady current that curves back on itself around a cape cannot be balanced without generating and shedding eddies. The process is modeled as follows. A westward flowing density current advances along a zonal wall and turns eastward after reaching the edge of the wall (i.e. the Cape of St Vincent). Integration of the steady (and inviscid) momentum equation along the wall gives the long-shore flow-force and shows that, no matter what the details of the turning process are, such a scenario is impossible. It corresponds to an unbalanced flow-force and, therefore, cannot exist. Namely, in an analogy to a rocket, the zonal longshore current forces the entire system to the west. A flow field that can compensate for such a force is westward drifting eddies that push the system to the east. In a similar fashion to the backward push associated with a firing cannon, the westward moving eddies (bullets) balance the integrated momentum of the flow around the cape. Nonlinear solutions are constructed analytically using an approach that enables one to compute the eddies' size and generation frequency without solving for the incredibly complicated details of the generation process itself. The method takes advantage of the fact that, after each eddy is generated, the system returns to its original structure. It is based on the integration of the momentum equation (for periodic flows) over a control volume and a perturbation expansion in ɛ, the ratio between the eddies' westward drift and the parent current speed. It is found that, because of the relatively small size of the Mediterranean eddies, β is not a sufficiently strong mechanism to remove the eddies (from the Cape of St Vincent) at the observed frequency. It is, therefore, concluded that westward advection must also take place. Specifically, it is found that an advection

Quantifying mesoscale eddies in the Lofoten Basin

NASA Astrophysics Data System (ADS)

Raj, R. P.; Johannessen, J. A.; Eldevik, T.; Nilsen, J. E. Ø.; Halo, I.

2016-07-01

The Lofoten Basin is the most eddy rich region in the Norwegian Sea. In this paper, the characteristics of these eddies are investigated from a comprehensive database of nearly two decades of satellite altimeter data (1995-2013) together with Argo profiling floats and surface drifter data. An automated method identified 1695/1666 individual anticyclonic/cyclonic eddies in the Lofoten Basin from more than 10,000 altimeter-based eddy observations. The eddies are found to be predominantly generated and residing locally. The spatial distributions of lifetime, occurrence, generation sites, size, intensity, and drift of the eddies are studied in detail. The anticyclonic eddies in the Lofoten Basin are the most long-lived eddies (>60 days), especially in the western part of the basin. We reveal two hotspots of eddy occurrence on either side of the Lofoten Basin. Furthermore, we infer a cyclonic drift of eddies in the western Lofoten Basin. Barotropic energy conversion rates reveals energy transfer from the slope current to the eddies during winter. An automated colocation of surface drifters trapped inside the altimeter-based eddies are used to corroborate the orbital speed of the anticyclonic and cyclonic eddies. Moreover, the vertical structure of the altimeter-based eddies is examined using colocated Argo profiling float profiles. Combination of altimetry, Argo floats, and surface drifter data is therefore considered to be a promising observation-based approach for further studies of the role of eddies in transport of heat and biomass from the slope current to the Lofoten Basin.

Methane fluxes above the Hainich forest by True Eddy Accumulation and Eddy Covariance

NASA Astrophysics Data System (ADS)

Siebicke, Lukas; Gentsch, Lydia; Knohl, Alexander

2016-04-01

Understanding the role of forests for the global methane cycle requires quantifying vegetation-atmosphere exchange of methane, however observations of turbulent methane fluxes remain scarce. Here we measured turbulent fluxes of methane (CH4) above a beech-dominated old-growth forest in the Hainich National Park, Germany, and validated three different measurement approaches: True Eddy Accumulation (TEA, closed-path laser spectroscopy), and eddy covariance (EC, open-path and closed-path laser spectroscopy, respectively). The Hainich flux tower is a long-term Fluxnet and ICOS site with turbulent fluxes and ecosystem observations spanning more than 15 years. The current study is likely the first application of True Eddy Accumulation (TEA) for the measurement of turbulent exchange of methane and one of the very few studies comparing open-path and closed-path eddy covariance (EC) setups side-by-side. We observed uptake of methane by the forest during the day (a methane sink with a maximum rate of 0.03 μmol m-2 s-1 at noon) and no or small fluxes of methane from the forest to the atmosphere at night (a methane source of typically less than 0.01 μmol m-2 s-1) based on continuous True Eddy Accumulation measurements in September 2015. First results comparing TEA to EC CO2 fluxes suggest that True Eddy Accumulation is a valid option for turbulent flux quantifications using slow response gas analysers (here CRDS laser spectroscopy, other potential techniques include mass spectroscopy). The TEA system was one order of magnitude more energy efficient compared to closed-path eddy covariance. The open-path eddy covariance setup required the least amount of user interaction but is often constrained by low signal-to-noise ratios obtained when measuring methane fluxes over forests. Closed-path eddy covariance showed good signal-to-noise ratios in the lab, however in the field it required significant amounts of user intervention in addition to a high power consumption. We conclude

A Baroclinic Eddy Mixer: Supercritical Transformation of Compensated Eddies

NASA Astrophysics Data System (ADS)

Sutyrin, G.

2016-02-01

In contrast to many real-ocean rings and eddies, circular vortices with initial lower layer at rest tend to be highly unstable in idealized two-layer models, unless their radius is made small or the lower layer depth is made artificially large. Numerical simulations of unstable vortices with parameters typical for ocean eddies revealed strong deformations and pulsations of the vortex core in the two-layer setup due to development of corotating tripolar structures in the lower layer during their supercritical transformation. The addition of a middle layer with the uniform potential vorticity weakens vertical coupling between the upper and lower layer that enhances vortex stability and makes the vortex lifespan more realistic. Such a three-layer vortex model possesses smaller lower interface slope than the two-layer model that reduces the potential vorticity gradient in the lower layer and provides with less unstable configurations. While cyclonic eddies become only slightly deformed and look nearly circular when the middle layer with uniform potential vorticity is added, anticyclonic eddies tend to corotating and pulsating elongated states through potential vorticity stripping and stirring. Enhanced vortex stability in such three-layer setup has important implications for adequate representation of the energy transfer across scales.

Eddies off Tasmania

NASA Technical Reports Server (NTRS)

2002-01-01

This true-color satellite image shows a large phytoplankton bloom, several hundred square kilometers in size, in the Indian Ocean off the west coast of Tasmania. In this scene, the rich concentration of microscopic marine plants gives the water a lighter, more turquoise appearance which helps to highlight the current patterns there. Notice the eddies, or vortices in the water, that can be seen in several places. It is possible that these eddies were formed by converging ocean currents flowing around Tasmania, or by fresh river runoff from the island, or both. Often, eddies in the sea serve as a means for stirring the water, thus providing nutrients that help support phytoplankton blooms, which in turn provide nutrition for other organisms. Effectively, these eddies help feed the sea (click to read an article on this topic). This image was acquired November 7, 2000, by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) flying aboard the Orbview-2 satellite. Tasmania is located off Australia's southeastern coast. Image courtesy SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

The pines of the Eddy Arboretum

Treesearch

John Duffield

1949-01-01

The Eddy Arboretum at Placerville, California, contains more than 90 species, varieties, and hybrids of pines, and is therefore of great interest to horticulturists. The Arboretum was established in 1925 as a source of breeding stock for the Eddy Tree Breeding Station, founded in the same year by Mr. James G. Eddy of Seattle. In 1934 Mr. Eddy presented the Arboretum...

Anatomy of a subtropical intrathermocline eddy

NASA Astrophysics Data System (ADS)

Barceló-Llull, Bàrbara; Sangrà, Pablo; Pallàs-Sanz, Enric; Barton, Eric D.; Estrada-Allis, Sheila N.; Martínez-Marrero, Antonio; Aguiar-González, Borja; Grisolía, Diana; Gordo, Carmen; Rodríguez-Santana, Ángel; Marrero-Díaz, Ángeles; Arístegui, Javier

2017-06-01

An interdisciplinary survey of a subtropical intrathermocline eddy was conducted within the Canary Eddy Corridor in September 2014. The anatomy of the eddy is investigated using near submesoscale fine resolution two-dimensional data and coarser resolution three-dimensional data. The eddy was four months old, with a vertical extension of 500 m and 46 km radius. It may be viewed as a propagating negative anomaly of potential vorticity (PV), 95% below ambient PV. We observed two cores of low PV, one in the upper layers centered at 85 m, and another broader anomaly located between 175 m and the maximum sampled depth in the three-dimensional dataset (325 m). The upper core was where the maximum absolute values of normalized relative vorticity (or Rossby number), |Ro| =0.6, and azimuthal velocity, U=0.5 m s-1, were reached and was defined as the eddy dynamical core. The typical biconvex isopleth shape for intrathermocline eddies induces a decrease of static stability, which causes the low PV of the upper core. The deeper low PV core was related to the occurrence of a pycnostad layer of subtropical mode water that was embedded within the eddy. The eddy core, of 30 km radius, was in near solid body rotation with period of 4 days. It was encircled by a thin outer ring that was rotating more slowly. The kinetic energy (KE) content exceeded that of available potential energy (APE), KE/APE=1.58; this was associated with a low aspect ratio and a relatively intense rate of spin as indicated by the relatively high value of Ro. Inferred available heat and salt content anomalies were AHA=2.9×1018 J and ASA=14.3×1010 kg, respectively. The eddy AHA and ASA contents per unit volume largely exceed those corresponding to Pacific Ocean intrathermocline eddies. This suggests that intrathermocline eddies may play a significant role in the zonal conduit of heat and salt along the Canary Eddy Corridor.

A True Eddy Accumulation - Eddy Covariance hybrid for measurements of turbulent trace gas fluxes

NASA Astrophysics Data System (ADS)

Siebicke, Lukas

2016-04-01

Eddy covariance (EC) is state-of-the-art in directly and continuously measuring turbulent fluxes of carbon dioxide and water vapor. However, low signal-to-noise ratios, high flow rates and missing or complex gas analyzers limit it's application to few scalars. True eddy accumulation, based on conditional sampling ideas by Desjardins in 1972, requires no fast response analyzers and is therefore potentially applicable to a wider range of scalars. Recently we showed possibly the first successful implementation of True Eddy Accumulation (TEA) measuring net ecosystem exchange of carbon dioxide of a grassland. However, most accumulation systems share the complexity of having to store discrete air samples in physical containers representing entire flux averaging intervals. The current study investigates merging principles of eddy accumulation and eddy covariance, which we here refer to as "true eddy accumulation in transient mode" (TEA-TM). This direct flux method TEA-TM combines true eddy accumulation with continuous sampling. The TEA-TM setup is simpler than discrete accumulation methods while avoiding the need for fast response gas analyzers and high flow rates required for EC. We implemented the proposed TEA-TM method and measured fluxes of carbon dioxide (CO2), methane (CH4) and water vapor (H2O) above a mixed beech forest at the Hainich Fluxnet and ICOS site, Germany, using a G2301 laser spectrometer (Picarro Inc., USA). We further simulated a TEA-TM sampling system using measured high frequency CO2 time series from an open-path gas analyzer. We operated TEA-TM side-by-side with open-, enclosed- and closed-path EC flux systems for CO2, H2O and CH4 (LI-7500, LI-7200, LI-6262, LI-7700, Licor, USA, and FGGA LGR, USA). First results show that TEA-TM CO2 fluxes were similar to EC fluxes. Remaining differences were similar to those between the three eddy covariance setups (open-, enclosed- and closed-path gas analyzers). Measured TEA-TM CO2 fluxes from our physical

Unified Ultrasonic/Eddy-Current Data Acquisition

NASA Technical Reports Server (NTRS)

Chern, E. James; Butler, David W.

1993-01-01

Imaging station for detecting cracks and flaws in solid materials developed combining both ultrasonic C-scan and eddy-current imaging. Incorporation of both techniques into one system eliminates duplication of computers and of mechanical scanners; unifies acquisition, processing, and storage of data; reduces setup time for repetitious ultrasonic and eddy-current scans; and increases efficiency of system. Same mechanical scanner used to maneuver either ultrasonic or eddy-current probe over specimen and acquire point-by-point data. For ultrasonic scanning, probe linked to ultrasonic pulser/receiver circuit card, while, for eddy-current imaging, probe linked to impedance-analyzer circuit card. Both ultrasonic and eddy-current imaging subsystems share same desktop-computer controller, containing dedicated plug-in circuit boards for each.

32 CFR 1900.43 - Determination(s) by Deputy Director(s).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Determination(s) by Deputy Director(s). 1900.43 Section 1900.43 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE... Administrative Appeals § 1900.43 Determination(s) by Deputy Director(s). Each Deputy Director in charge of a...

Tools and Methods for Visualization of Mesoscale Ocean Eddies

NASA Astrophysics Data System (ADS)

Bemis, K. G.; Liu, L.; Silver, D.; Kang, D.; Curchitser, E.

2017-12-01

Mesoscale ocean eddies form in the Gulf Stream and transport heat and nutrients across the ocean basin. The internal structure of these three-dimensional eddies and the kinematics with which they move are critical to a full understanding of their transport capacity. A series of visualization tools have been developed to extract, characterize, and track ocean eddies from 3D modeling results, to visually show the ocean eddy story by applying various illustrative visualization techniques, and to interactively view results stored on a server from a conventional browser. In this work, we apply a feature-based method to track instances of ocean eddies through the time steps of a high-resolution multidecadal regional ocean model and generate a series of eddy paths which reflect the life cycle of individual eddy instances. The basic method uses the Okubu-Weiss parameter to define eddy cores but could be adapted to alternative specifications of an eddy. Stored results include pixel-lists for each eddy instance, tracking metadata for eddy paths, and physical and geometric properties. In the simplest view, isosurfaces are used to display eddies along an eddy path. Individual eddies can then be selected and viewed independently or an eddy path can be viewed in the context of all eddy paths (longer than a specified duration) and the ocean basin. To tell the story of mesoscale ocean eddies, we combined illustrative visualization techniques, including visual effectiveness enhancement, focus+context, and smart visibility, with the extracted volume features to explore eddy characteristics at multiple scales from ocean basin to individual eddy. An evaluation by domain experts indicates that combining our feature-based techniques with illustrative visualization techniques provides an insight into the role eddies play in ocean circulation. A web-based GUI is under development to facilitate easy viewing of stored results. The GUI provides the user control to choose amongst available

Eddy properties in the Southern California Current System

NASA Astrophysics Data System (ADS)

Chenillat, Fanny; Franks, Peter J. S.; Capet, Xavier; Rivière, Pascal; Grima, Nicolas; Blanke, Bruno; Combes, Vincent

2018-05-01

The California Current System (CCS) is an eastern boundary upwelling system characterized by strong eddies that are often generated at the coast. These eddies contribute to intense, long-distance cross-shelf transport of upwelled water with enhanced biological activity. However, the mechanisms of formation of such coastal eddies, and more importantly their capacity to trap and transport tracers, are poorly understood. Their unpredictability and strong dynamics leave us with an incomplete picture of the physical and biological processes at work, their effects on coastal export, lateral water exchange among eddies and their surrounding waters, and how long and how far these eddies remain coherent structures. Focusing our analysis on the southern part of the CCS, we find a predominance of cyclonic eddies, with a 25-km radius and a SSH amplitude of 6 cm. They are formed near shore and travel slightly northwest offshore for 190 days at 2 km day-1. We then study one particular, representative cyclonic eddy using a combined Lagrangian and Eulerian numerical approach to characterize its kinematics. Formed near shore, this eddy trapped a core made up of 67% California Current waters and 33% California Undercurrent waters. This core was surrounded by other waters while the eddy detached from the coast, leaving the oldest waters at the eddy's core and the younger waters toward the edge. The eddy traveled several months as a coherent structure, with only limited lateral exchange within the eddy.

Joint Chiefs of Staff > Directorates > Directorates of Management

Science.gov Websites

establishes information management requirements and manages the corporate Joint Staff decision process to Force Chief of Staff Chief of National Guard Bureau Biographies Directorates Directorates of Management J8 | Force Structure, Resources & Assessment Contact Directorate of Management Home

Improved Imaging With Laser-Induced Eddy Currents

NASA Technical Reports Server (NTRS)

Chern, Engmin J.

1993-01-01

System tests specimen of material nondestructively by laser-induced eddy-current imaging improved by changing method of processing of eddy-current signal. Changes in impedance of eddy-current coil measured in absolute instead of relative units.

Moffatt eddies at an interface

NASA Astrophysics Data System (ADS)

Shtern, Vladimir

2014-12-01

It is shown that an infinite set of eddies can develop near the interface-wall intersection in a two-fluid flow. A striking feature is that the eddy occurrence depends on from what side of the interface the flow is driven. In air-water flows where the viscosity ratio is 0.018, the eddies develop if a driving source is located on (i) the air side for , (ii) any side for , and (iii) the water side for , where is the upper interface-wall angle.

Automated eddy current analysis of materials

NASA Technical Reports Server (NTRS)

Workman, Gary L.

1991-01-01

The use of eddy current techniques for characterizing flaws in graphite-based filament-wound cylindrical structures is described. A major emphasis was also placed upon incorporating artificial intelligence techniques into the signal analysis portion of the inspection process. Developing an eddy current scanning system using a commercial robot for inspecting graphite structures (and others) was a goal in the overall concept and is essential for the final implementation for the expert systems interpretation. Manual scans, as performed in the preliminary work here, do not provide sufficiently reproducible eddy current signatures to be easily built into a real time expert system. The expert systems approach to eddy current signal analysis requires that a suitable knowledge base exist in which correct decisions as to the nature of a flaw can be performed. A robotic workcell using eddy current transducers for the inspection of carbon filament materials with improved sensitivity was developed. Improved coupling efficiencies achieved with the E-probes and horseshoe probes are exceptional for graphite fibers. The eddy current supervisory system and expert system was partially developed on a MacIvory system. Continued utilization of finite element models for predetermining eddy current signals was shown to be useful in this work, both for understanding how electromagnetic fields interact with graphite fibers, and also for use in determining how to develop the knowledge base. Sufficient data was taken to indicate that the E-probe and the horseshoe probe can be useful eddy current transducers for inspecting graphite fiber components. The lacking component at this time is a large enough probe to have sensitivity in both the far and near field of a thick graphite epoxy component.

Eddy Current Testing, RQA/M1-5330.17.

ERIC Educational Resources Information Center

National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

As one in the series of classroom training handbooks, prepared by the U.S. space program, instructional material is presented in this volume concerning familiarization and orientation on eddy current testing. The subject is presented under the following headings: Introduction, Eddy Current Principles, Eddy Current Equipment, Eddy Current Methods,…

A comparison of the structure, properties, and water mass composition of quasi-isotropic eddies in western boundary currents in an eddy-resolving ocean model

NASA Astrophysics Data System (ADS)

Rykova, Tatiana; Oke, Peter R.; Griffin, David A.

2017-06-01

Using output from a near-global eddy-resolving ocean model, we analyse the properties and characteristics of quasi-isotropic eddies in five Western Boundary Current (WBC) regions, including the extensions of the Agulhas, East Australian Current (EAC), Brazil-Malvinas Confluence (BMC), Kuroshio and Gulf Stream regions. We assess the model eddies by comparing to satellite and in situ observations, and show that most aspects of the model's representation of eddies are realistic. We find that the mean eddies differ dramatically between these WBC regions - all with some unique and noteworthy characteristics. We find that the vertical displacement of isopycnals of Agulhas eddies is the greatest, averaging 350-450 m at depths of over 800-900 m. EAC (BMC) eddies are the least (most) barotropic, with only 50% (85-90%) of the velocity associated with the barotropic mode. Kuroshio eddies are the most stratified, resulting in small isopycnal displacement, even for strong eddies; and Gulf Stream eddies carry the most heat. Despite their differences, we explicitly show that the source waters for anticyclonic eddies are a mix of the WBC water (from the boundary current itself) and water that originates equatorward of the WBC eddy-field; and cyclonic eddies are a mix of WBC water and water that originates poleward of the WBC eddy-field.

Eddy current damper

NASA Technical Reports Server (NTRS)

Ellis, R. C.; Fink, R. A.; Rich, R. W.

1989-01-01

A high torque capacity eddy current damper used as a rate limiting device for a large solar array deployment mechanism is discussed. The eddy current damper eliminates the problems associated with the outgassing or leaking of damping fluids. It also provides performance advantages such as damping torque rates, which are truly linear with respect to input speed, continuous 360 degree operation in both directions of rotation, wide operating temperature range, and the capability of convenient adjustment of damping rates by the user without disassembly or special tools.

A western boundary current eddy characterisation study

NASA Astrophysics Data System (ADS)

Ribbe, Joachim; Brieva, Daniel

2016-12-01

The analysis of an eddy census for the East Australian Current (EAC) region yielded a total of 497 individual short-lived (7-28 days) cyclonic and anticyclonic eddies for the period 1993 to 2015. This was an average of about 23 eddies per year. 41% of the tracked individual cyclonic and anticyclonic eddies were detected off southeast Queensland between about 25 °S and 29 °S. This is the region where the flow of the EAC intensifies forming a swift western boundary current that impinges near Fraser Island on the continental shelf. This zone was also identified as having a maximum in detected short-lived cyclonic eddies. A total of 94 (43%) individual cyclonic eddies or about 4-5 per year were tracked in this region. The census found that these potentially displaced entrained water by about 115 km with an average displacement speed of about 4 km per day. Cyclonic eddies were likely to contribute to establishing an on-shelf longshore northerly flow forming the western branch of the Fraser Island Gyre and possibly presented an important cross-shelf transport process in the life cycle of temperate fish species of the EAC domain. In-situ observations near western boundary currents previously documented the entrainment, off-shelf transport and export of near shore water, nutrients, sediments, fish larvae and the renewal of inner shelf water due to short-lived eddies. This study found that these cyclonic eddies potentially play an important off-shelf transport process off the central east Australian coast.

Baroclinic Adjustment of the Eddy-Driven Jet

NASA Astrophysics Data System (ADS)

Novak, Lenka; Ambaum, Maarten H. P.; Harvey, Ben J.

2017-04-01

The prediction of poleward shift in the midlatitude eddy-driven jets due to anthropogenic climate change is now a robust feature of climate models, but the magnitude of this shift or the processes responsible for it are less certain. This uncertainty comes from the complex response in storm tracks to large-scale forcing and their nonlinear modulation of the jet. This study uses global circulation models to reveal a relationship between eddy growth rate (referred to as baroclinicity) and eddy activity, whereby baroclinicity responds most rapidly to an eddy-dissipating forcing whereas eddy activity responds most rapidly to a baroclinicity-replenishing forcing. This nonlinearity can be generally explained using a two-dimensional dynamical system essentially describing the baroclinic adjustment as a predator-prey relationship. Despite this nonlinearity, the barotropic changes in the eddy-driven jet appear to be of a comparable magnitude for the ranges of both types of forcing tested in this study. It is implied that while changes in eddy activity or baroclinicity may indicate the sign of latitudinal jet shifting, the precise magnitude of this shifting is a result of a balance between these two quantities.

Wind Forced Variability in Eddy Formation, Eddy Shedding, and the Separation of the East Australian Current

NASA Astrophysics Data System (ADS)

Bull, Christopher Y. S.; Kiss, Andrew E.; Jourdain, Nicolas C.; England, Matthew H.; van Sebille, Erik

2017-12-01

The East Australian Current (EAC), like many other subtropical western boundary currents, is believed to be penetrating further poleward in recent decades. Previous observational and model studies have used steady state dynamics to relate changes in the westerly winds to changes in the separation behavior of the EAC. As yet, little work has been undertaken on the impact of forcing variability on the EAC and Tasman Sea circulation. Here using an eddy-permitting regional ocean model, we present a suite of simulations forced by the same time-mean fields, but with different atmospheric and remote ocean variability. These eddy-permitting results demonstrate the nonlinear response of the EAC to variable, nonstationary inhomogeneous forcing. These simulations show an EAC with high intrinsic variability and stochastic eddy shedding. We show that wind stress variability on time scales shorter than 56 days leads to increases in eddy shedding rates and southward eddy propagation, producing an increased transport and southward reach of the mean EAC extension. We adopt an energetics framework that shows the EAC extension changes to be coincident with an increase in offshore, upstream eddy variance (via increased barotropic instability) and increase in subsurface mean kinetic energy along the length of the EAC. The response of EAC separation to regional variable wind stress has important implications for both past and future climate change studies.

Effects of eddy initial conditions on nonlinear forcing of planetary scale waves by amplifying baroclinic eddies

NASA Technical Reports Server (NTRS)

Young, Richard E.

1986-01-01

The previous study of Young and Villere concerning growth of planetary scale waves forced by wave-wave interactions of amplifying intermediate scale baroclinic eddies is extended to investigate effects of different eddy initial conditions. A global, spectral, primitive equation model is used for the calculations. For every set of eddy initial conditions considered, growth rates of planetary modes are considerably greater than growth rates computed from linear instability theory for a fixed zonally independent basic state. However, values of growth rates ranged over a factor of 3 depending on the particular set of eddy initial conditions used. Nonlinear forcing of planetary modes via wave-wave coupling becomes more important than baroclinic growth on the basic state at small values of the intermediate-scale modal amplitudes. The relative importance of direct transfer of kinetic energy from intermediate scales of motion to a planetary mode, compared to baroclinic conversion of available potential energy to kinetic energy within that planetary mode, depends on the individual case. In all cases, however, the transfer of either kinetic or available potential energy to the planetary modes was accomplished principally by wave-wave transfer from intermediate scale eddies, rather than from the zonally averaged state. The zonal wavenumber 2 planetary mode was prominent in all solutions, even in those for which eddy initial conditions were such that a different planetary mode was selectively forced at the start. General characteristics of the structural evolution of the planetary wave components of total heat and momentum flux, and modal structures themselves, were relatively insensitive to variations in eddy initial conditions, even though quantitative details varied from case to case.

Eddies off the Queen Charlotte Islands

NASA Technical Reports Server (NTRS)

2002-01-01

The bright red, green, and turquoise patches to the west of British Columbia's Queen Charlotte Islands and Alaska's Alexander Archipelago highlight the presence of biological activity in the ocean. These colors indicate high concentrations of chlorophyll, the primary pigment found in phytoplankton. Notice that there are a number of eddies visible in the Pacific Ocean in this pseudo-color scene. The eddies are formed by strong outflow currents from rivers along North America's west coast that are rich in nutrients from the springtime snowmelt running off the mountains. This nutrient-rich water helps stimulate the phytoplankton blooms within the eddies. (For more details, read Tracking Eddies that Feed the Sea.) To the west of the eddies in the water, another type of eddy-this one in the atmosphere-forms the clouds into the counterclockwise spiral characteristic of a low pressure system in the Northern Hemisphere. (Click on the image above to see it at full resolution; or click to see the scene in true-color.) The snow-covered mountains of British Columbia are visible in the upper righthand corner of the image. This scene was constructed using SeaWiFS data collected on June 13, 2002. SeaWiFS image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

Determination of eddy current response with magnetic measurements.

PubMed

Jiang, Y Z; Tan, Y; Gao, Z; Nakamura, K; Liu, W B; Wang, S Z; Zhong, H; Wang, B B

2017-09-01

Accurate mutual inductances between magnetic diagnostics and poloidal field coils are an essential requirement for determining the poloidal flux for plasma equilibrium reconstruction. The mutual inductance calibration of the flux loops and magnetic probes requires time-varying coil currents, which also simultaneously drive eddy currents in electrically conducting structures. The eddy current-induced field appearing in the magnetic measurements can substantially increase the calibration error in the model if the eddy currents are neglected. In this paper, an expression of the magnetic diagnostic response to the coil currents is used to calibrate the mutual inductances, estimate the conductor time constant, and predict the eddy currents response. It is found that the eddy current effects in magnetic signals can be well-explained by the eddy current response determination. A set of experiments using a specially shaped saddle coil diagnostic are conducted to measure the SUNIST-like eddy current response and to examine the accuracy of this method. In shots that include plasmas, this approach can more accurately determine the plasma-related response in the magnetic signals by eliminating the field due to the eddy currents produced by the external field.

Eddy-Current Inspection Of Graphite-Fiber Composites

NASA Technical Reports Server (NTRS)

Workman, G. L.; Bryson, C. C.

1993-01-01

NASA technical memorandum describes initial research on, and proposed development of, automated system for nondestructive eddy-current inspection of parts made of graphite-fiber/epoxy-matrix composite materials. Sensors in system E-shaped or U-shaped eddy-current probes like those described in "Eddy-Current Probes For Inspecting Graphite-Fiber Composites" (MFS-26129).

The decay of a simple eddy

NASA Technical Reports Server (NTRS)

Bateman, H

1923-01-01

The principal result obtained in this report is a generalization of Taylor's formula for a simple eddy. The discussion of the properties of the eddy indicates that there is a slight analogy between the theory of eddies in a viscous fluid and the quantum theory of radiation. Another exact solution of the equations of motion of viscous fluid yields a result which reminds one of the well-known condition for instability in the case of a horizontally stratified atmosphere.

Eddy-Kuroshio Interactions: Local and Remote Effects

NASA Astrophysics Data System (ADS)

Jan, Sen; Mensah, Vigan; Andres, Magdalena; Chang, Ming-Huei; Yang, Yiing Jang

2017-12-01

Quasi-geostrophic mesoscale eddies regularly impinge on the Kuroshio in the western North Pacific, but the processes underlying the evolution of these eddy-Kuroshio interactions have not yet been thoroughly investigated in the literature. Here this interaction is examined with results from a semi-idealized three-dimensional numerical model and observations from four pressure-sensor equipped inverted echo sounders (PIESs) in a zonal section east of Taiwan and satellite altimeters. Both the observations and numerical simulations suggest that, during the interaction of a cyclonic eddy with the Kuroshio, the circular eddy is deformed into an elliptic shape with the major axis in the northwest-southeast direction, before being dissipated; the poleward velocity and associated Kuroshio transport decrease and the sea level and pycnocline slopes across the Kuroshio weaken. In contrast, for an anticyclonic eddy during the eddy-Kuroshio interaction, variations in the velocity, sea level, and isopycnal depth are reversed; the circular eddy is also deformed to an ellipse but with the major axis parallel to the Kuroshio. The model results also demonstrate that the velocity field is modified first and consequently the SSH and isopycnal depth evolve during the interaction. Furthermore, due to the combined effect of impingement latitude and realistic topography, some eddy-Kuroshio interactions east of Taiwan are found to have remote effects, both in the Luzon Strait and on the East China Sea shelf northeast of Taiwan.