Sample records for hillsboro ks boundary

  1. Hillsboro, Oregon: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio:GreerHi Gtel Jump to:County, Ohio:Hilliard, Ohio:HillsboroHillsboro,

  2. Energy Department Recognizes Cities of Beaverton and Hillsboro...

    Broader source: Energy.gov (indexed) [DOE]

    today recognized the cities of Beaverton and Hillsboro, as well as the Portland Public School District for their leadership in reducing energy use. As Better Buildings Challenge...

  3. Hillsboro Ranches, Florida: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio:GreerHi Gtel Jump to:County, Ohio:Hilliard, Ohio:Hillsboro

  4. City of Hillsboro, North Dakota (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector GeneralDepartmentAUDITOhio (Utility Company)Galion,Harrisonville,Hickman Place:IllinoisHillsboro

  5. Hillsboro Pines, Florida: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio:GreerHi Gtel Jump to:County, Ohio:Hilliard, Ohio:Hillsboro Pines,

  6. Hillsboro BF #1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun withconfinement plasmas in theinPlasticsreduction . |

  7. Hillsboro Extended Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun withconfinement plasmas in theinPlasticsreduction . |

  8. Incompatible Statistics and Bell-KS Theorem

    E-Print Network [OSTI]

    Ángel Rivas

    2015-01-20T23:59:59.000Z

    We analyze a possible loophole to the conclusion of the Bell-KS theorem that quantum mechanics is not compatible with any realistic and noncontextual or local theory. We emphasize that the models discarded by Bell-KS-like arguments possess a property not shared by quantum mechanics, i.e. the capability to make non-trivial statements about the joint statistics of quantum incompatible observables. By ruling out this possibility, apparently nothing seems to prevent from a realistic, noncontextual or local view of quantum mechanics.

  9. K/S Relay Issue 4

    E-Print Network [OSTI]

    Fish, L.; Rathbone, W.

    1982-01-01T23:59:59.000Z

    ?' lEEL^U A CONTENTS This Deadly Innocence or "The End of the Hurt/Comfort Syndrome" by Leslie Fish 5 Axtivonk by Roo. Re.pA*.\\ite.d &Aom Nake.d Th)\\eA 3. **************** Lester's Complaint by Leslie Fish 68 Aitwoxk by Ann Hamplviey Rep...Alal. K/S RELAY 4 1982 (c) Janet Hunt. Once again Relay is reprinting some of Leslie Fish's marvellous K/S stories, THIS DEADLY INNOCENCE or The End of the Hurt/Comfort Syndrome is, in my opinion, just about the most exciting and well written story...

  10. Cross sections for the reactions $e^+ e^-\\to K_S^0 K_L^0$, $K_S^0 K_L^0 ?^+?^-$, $K_S^0 K_S^0 ?^+?^-$, and $K_S^0 K_S^0 K^+K^-$ from events with initial-state radiation

    E-Print Network [OSTI]

    The BABAR Collaboration; J. P. Lees

    2014-03-29T23:59:59.000Z

    We study the processes $e^+ e^-\\to K_S^0 K_L^0 \\gamma$, $K_S^0 K_L^0 \\pi^+\\pi^-\\gamma$, $K_S^0 K_S^0 \\pi^+\\pi^-\\gamma$, and $K_S^0 K_S^0 K^+K^-\\gamma$, where the photon is radiated from the initial state, providing cross section measurements for the hadronic states over a continuum of center-of-mass energies. The results are based on 469 fb$^{-1}$ of data collected with the BaBar detector at SLAC. We observe the $\\phi(1020)$ resonance in the $K_S^0 K_L^0$ final state and measure the product of its electronic width and branching fraction with about 3% uncertainty. We present a measurement of the $e^+ e^-\\to K_S^0 K_L^0 $ cross section in the energy range from 1.06 to 2.2 GeV and observe the production of a resonance at 1.67 GeV. We present the first measurements of the $e^+ e^-\\to K_S^0 K_L^0 \\pi^+\\pi^-$, $K_S^0 K_S^0 \\pi^+\\pi^-$, and $K_S^0 K_S^0 K^+K^-$ cross sections, and study the intermediate resonance structures. We obtain the first observations of \\jpsi decay to the $K_S^0 K_L^0 \\pi^+\\pi^-$, $K_S^0 K_S^0 \\pi^+\\pi^-$, and $K_S^0 K_S^0 K^+K^-$ final states.

  11. Reference Inside KS1992 Tray Inside Air

    E-Print Network [OSTI]

    Llope, William J.

    Reference Inside KS1992 0.2 Tray Inside Air 0.5 Tray Inside Air 0.8 Tray Inside Air 0.2 Tray Side Wall Inner 0.2 Tray Side Wall Inner Under TAMP near sensor pos4 Under TAMP near sensor pos4 Air Gap Below TDIG pos1 Air Gap Below TDIG pos4 Air Gap Below TDIG pos6 HPTDC1 Chip pos6 HPTDC4 Chip pos6 HPTDC2

  12. Category:Wichita, KS | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarreis aCallahanWindSyracuse, NY JumpKS" The following 16

  13. Measurement of the KS->gg branching ratio using a pure KS beam with the KLOE detector

    E-Print Network [OSTI]

    The KLOE collaboration

    2008-05-08T23:59:59.000Z

    We have searched for the decay KS->gg in a sample of 2x10^9 phi->KS KL decays collected at DAPHNE with an integrated luminosity of 1.9 fb^{-1}. KS are tagged by the KL interaction in the calorimeter. Two prompt photons must also be detected. Kinematic constraints reduce the initial 6x10^5 events to 2740 candidates, from which a signal of 711\\pm 35 events is extracted. By normalizing to the KS->2pi^0 decays counted in the same sample, we measure BR(KS->gg)= (2.26\\pm0.12_{stat}\\pm0.06_{syst})x10^{-6}, in agreement with O(p^4) Chiral Perturbation Theory predictions.

  14. CircleKs DEFINITIVE vim Reference Version: 1.0

    E-Print Network [OSTI]

    CircleKs DEFINITIVE vim Reference Version: 1.0 Major rules: 1. Vim has 2 modes: insert and command inserting text s! Cut character under cursor and start inserting text After youre in insert mode, vim

  15. Re (epsilon'/epsilon_K) vs. B_d -> phi K_S CP asymmetry

    E-Print Network [OSTI]

    P. Ko; A. Masiero; Jae-hyeon Park

    2005-07-20T23:59:59.000Z

    In a SUSY GUT seesaw scenario, the largeness of the atmospheric neutrino mixing can reflect itself into an enhanced flavor changing mixing of beauty and strange right-handed scalar quarks. If the CP violating phase in such down type squark RR insertion is the main source of CP asymmetry in B_d -> phi K_S and the gluino contributions to K0-K0 bar and B0-B0 bar mixing are negligible, there is a correlation between Re (epsilon'/epsilon_K) and B_d -> phi K_S CP asymmetry, in addition to that with the strange quark CEDM. The current data on Re (epsilon'/epsilon_K) = (16.7 +- 2.6) 10^-4 imply that S_{phi K} should be greater than \\sim 0.5 (0.25) for mu tan beta = 1 (5) TeV, assuming the RR dominance in b -> s transition and the minimal supergravity type boundary conditions for soft parameters.

  16. Wirebonding SVX prime silicon ladders using the K&S 1478 wirebonder

    SciTech Connect (OSTI)

    Dyer, A.

    1993-09-01T23:59:59.000Z

    This report discusses the follow on the K&S 1478 Wirebonder: Power Up; Tool Calibration; Manual Mode; Teach Mode; and Reference Systems.

  17. Hillsboro, Texas: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio:GreerHi Gtel Jump to:County, Ohio:Hilliard,

  18. Search for the CP symmetry violation in the decays of Ks mesons using the KLOE detector

    E-Print Network [OSTI]

    M. Silarski

    2013-02-19T23:59:59.000Z

    The aim of this work was to determine the KS -> 3pi0 decay branching ratio and a modulus of the eta000 parameter, defined as the ratio of amplitudes for KS -> 3 pi0 to KL -> 3pi0 decays, which characterizes the CP symmetry violation in this decay. The measurement has been carried out with the KLOE detector operating at the phi-factory DAFNE in the Italian National Center for Nuclear Physics in Frascati. The KS mesons were identified with high efficiency via registration of these KL mesons which crossed the drift chamber without decaying and then interacted with the KLOE electromagnetic calorimeter. The KS four-momentum vector was then determined using the registered position of the KL meson and the known momentum of the phi meson. Next, the search for the KS -> 3pi0 -> 6gamma decay was carried out by the selection of events with six gamma quanta which momenta were reconstructed using time and energy measured by the electromagnetic calorimeter. To increase the signal over background ratio after identification of the KS meson and requiring six reconstructed photons a discriminant analysis is performed. It is based on kinematical fit, testing of the signal and background hypotheses and exploiting of the differences in kinematics of the KS decays into 2pi0 and 3pi0. Hence, we have obtained the upper limit on the KS -> 3pi0 branching ratio at the 90% confidence level BR(KS -> 3pi0)KS -> 3pi0 decay presented in this work failed to detect a signal of sufficient statistical significance. This upper limit can be translated into a limit on the modulus of the eta000 parameter amounting to: |eta000| < 0.009 at the 90% confidence level.

  19. Study of Penguin Pollution in the B^0 -> J/psi K_S Decay

    E-Print Network [OSTI]

    Satoshi Mishima

    2007-03-18T23:59:59.000Z

    We study the penguin pollution in the B^0 -> J/psi K_S decay up to leading power in 1/m_b and to next-to-leading order in \\alpha_s, m_b being the b quark mass and \\alpha_s the strong coupling constant. The deviation \\Delta S_{J/psi K_S} of the mixing-induced CP asymmetry from sin(2\\phi_1) and the direct CP asymmetry A_{J/psi K_S} are both found to be of O(10^{-3}) in a formalism that combines the QCD-improved factorization and perturbative QCD approaches.

  20. NuSTAR DISCOVERY OF A CYCLOTRON LINE IN KS 1947+300

    E-Print Network [OSTI]

    Pottschmidt, Katja

    We present a spectral analysis of three simultaneous Nuclear Spectroscopy Telescope Array and Swift/XRT observations of the transient Be-neutron star binary KS 1947+300 taken during its outburst in 2013/2014. These broadband ...

  1. Lyapunov Exponents and KS Entropy for the Lorentz Gas at Low Densities

    E-Print Network [OSTI]

    Henk van Beijeren; J. R. Dorfman

    1994-12-26T23:59:59.000Z

    The Lyapunov exponents and the KS entropy for a two dimensional Lorentz gas at low densities are defined for general non-equilibrium states and calculated with the use of a Lorentz-Boltzmann type equation. In equilibrium the density dependence of these quantities predicted by Krylov is recovered and explicit expressions are obtained. The relationship between the KS entropy, Lyapunov exponents, and escape rate, conjectured by Gaspard and Nicolis for non-equilibrium systems is confirmed and generalized.

  2. The running coupling in lattice Landau gauge with unquenched Wilson fermion and KS fermion

    E-Print Network [OSTI]

    Sadataka Furui; Hideo Nakajima

    2005-11-22T23:59:59.000Z

    The running coupling of the Wilson fermon(JLQCD/CP-PACS) and that of Kogut-Susskind(KS) fermion(MILC) are measured in the lattice Landau gauge QCD in $\\widetilde{MOM}$ scheme. The quark propagator of the KS fermion is also measured and we find that it is infrared suppressed. The renormalization factor of the running coupling and the tadpole renormalization define the scale of the quark wave function. Effects of the $A_\\mu^2$ condensates of a few GeV$^2$ are observed in the running coupling and also in the quark propagator.

  3. Improved $K_S$ tagging procedure and its impact on physics at KLOE-2

    E-Print Network [OSTI]

    Silarski, M

    2015-01-01T23:59:59.000Z

    The KLOE experiment at the DA$\\Phi$NE $\\phi$-factory performed precise studies of charged and neutral kaon physics, low energy QCD, as well as tests of CP and CPT invariance. For the new run the KLOE has been upgraded by adding new tagger systems for the $\\gamma\\gamma$ physics, the inner tracking chamber and two calorimeters in the final focusing region. We are also improving on kaon identification techniques, in particular algorithms for the $K_S$ meson tagging. In this article we discuss the impact of the improved tagging procedure on studies of the $K_S$ decays.

  4. Penguin pollution in the B^0 -> J/psi K_S decay

    E-Print Network [OSTI]

    Hsiang-nan Li; Satoshi Mishima

    2007-03-02T23:59:59.000Z

    We present the most complete analysis of the penguin correction to the extraction of the standard-model parameter sin(2\\phi_1) from the B^0 -> J/psi K_S decay up to leading power in 1/m_b and to next-to-leading order in \\alpha_s, \\phi_1 being the weak phase, m_b the b quark mass, and \\alpha_s the strong coupling constant. The deviation \\Delta S_{J/psi K_S} of the mixing-induced CP asymmetry from sin(2\\phi_1) and the direct CP asymmetry A_{J/psi K_S} are both found to be of O(10^{-3}) in a formalism that combines the QCD-improved factorization and perturbative QCD approaches. The above results, different from those of O(10^{-4}) and of O(10^{-2}) obtained in the previous calculations, provide an important standard-model reference for verifying new physics from the B^0 -> J/psi K_S data.

  5. Dalitz analysis of D-0 -> K-S(0)pi(+)pi(-)

    E-Print Network [OSTI]

    Ammar, Raymond G.; Besson, David Zeke; Zhao, X.

    2002-12-01T23:59:59.000Z

    In e(+)e(-) collisions using the CLEO detector, we have studied the decay of the D-0 to the final state K(S)(0)pi(+)pi(-) with the initial flavor of the D-0 tagged by the decay D*+-->D(0)pi(+). We use the Dalitz technique to measure the resonant...

  6. Boundary-Layer Meteorol (2010) 134:157180 DOI 10.1007/s10546-009-9433-z

    E-Print Network [OSTI]

    Gentine, Pierre

    of potential temperature w (Kms-1) Ks Soil thermal diffusivity (nominal value is 2.5 � 10-7 m2 s-1) k VonBoundary-Layer Meteorol (2010) 134:157­180 DOI 10.1007/s10546-009-9433-z ARTICLE Spectral Behaviour

  7. THSE DE DOCTORAT D'TAT ks SCIENCES PHYSIQUES A LA FACULT~DES SCtEtCES DE PARIS

    E-Print Network [OSTI]

    Boyer, Edmond

    TH�SE DE DOCTORAT D'�TAT ks SCIENCES PHYSIQUES présentée A LA FACULT~DES SCtEtüCES DE PARIS pour

  8. Broad band X-ray spectrum of KS 1947+300 with BeppoSAX

    E-Print Network [OSTI]

    S. Naik; P. J. Callanan; B. Paul; T. Dotani

    2006-05-01T23:59:59.000Z

    We present results obtained from three BeppoSAX observations of the accretion-powered transient X-ray pulsar KS 1947+300 carried out during the declining phase of its 2000 November -- 2001 June outburst. A detailed spectral study of KS 1947+300 across a wide X-ray band (0.1--100.0 keV) is attempted for the first time here. Timing analysis of the data clearly shows a 18.7 s pulsation in the X-ray light curves in the above energy band. The pulse profile of KS 1947+300 is characterized by a broad peak with sharp rise followed by a narrow dip. The dip in the pulse profile shows a very strong energy dependence. Broad-band pulse-phase-averaged spectroscopy obtained with three of the BeppoSAX instruments shows that the energy spectrum in the 0.1--100 keV energy band has three components, a Comptonized component, a ~0.6 keV blackbody component, and a narrow and weak iron emission line at 6.7 keV with a low column density of material in the line of sight. We place an upper limit on the equivalent width of the iron K_\\alpha line at 6.4 keV of ~13 eV (for a width of 100 eV). Assuming a spherical blackbody emitting region and the distance of the source to be 10 kpc, the radius of the emitting region is found to be in the range of 14--22 km, which rules out the inner accretion disk as the soft X-ray emitting region.

  9. DOE - Office of Legacy Management -- Spencer Chemical Co - KS 0-01

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofof EnergyYou are herePAOsborneSavannahIllinois SiteSouthKS 0-01

  10. File:USDA-CE-Production-GIFmaps-KS.pdf | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublicIDAPowerPlantSitingConstruction.pdfNotify98.pdf Jump to: navigation,storage planIL.pdf Jump to:KS.pdf Jump

  11. Workplace Charging Challenge Partner: City of Hillsboro | Department of

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment of Energyof EnergyEnergy Cisco Systems,

  12. Hillsboro Beach, Florida: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio:GreerHi Gtel Jump to:County, Ohio:Hilliard, Ohio:

  13. Energy Department Recognizes Cities of Beaverton and Hillsboro, Oregon,

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector General Office of Audit| DepartmentNumber: 1-800-244-3301Geothermal DevelopmentCarbon

  14. City of Hillsboro, Kansas (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector GeneralDepartmentAUDITOhio (Utility Company)Galion,Harrisonville,Hickman Place:Illinois

  15. Optical observations of Be/X-ray transient system KS 1947+300

    E-Print Network [OSTI]

    U. Kiziloglu; A. Baykal; N. Kiziloglu

    2006-08-05T23:59:59.000Z

    ROTSE-IIId observations of the Be/X-ray transient system KS 1947+300 obtained between September 2004 and December 2005 make it possible to study the correlation between optical and X-ray activity. The optical outburst of 0.1 mag was accompanied by an increase in X-ray flux in 2004 observations. Strong correlation between the optical and X-ray light curves suggests that neutron star directly accretes from the outflowing material of Be star. The nearly zero time lag between X-ray and optical light curves suggests a heating of the disk of Be star by X-rays. No optical brightening and X-ray enhancement was seen in 2005 observations. There is no indication of the orbital modulation in the optical light curve.

  16. The many-body problem A solution: DFT HK theorems KS scheme Summary Key concepts in Density Functional Theory (I)

    E-Print Network [OSTI]

    Botti, Silvana

    's University, Belfast Key concepts in Density Functional Theory (I) Silvana Botti #12;The many-body problem concepts in Density Functional Theory (I) Silvana Botti #12;The many-body problem A solution: DFT HK theorems KS scheme Summary Outline 1 The many-body problem 2 A solution: Density Functional Theory 3

  17. Dates Days Activity Location Deadline Cost June 9 Sun. Kayaking Harpeth River, TN (KS to GT) 5/31 $33

    E-Print Network [OSTI]

    Bordenstein, Seth

    Dates Days Activity Location Deadline Cost June 9 Sun. Kayaking Harpeth River, TN (KS to GT) 5/31 $33 15 Sat. Canoeing * Families welcome * Harpeth River, TN (The Narrows) 6/7 $22 16 Sun. Hike, TN 6/14 $22 21-23 Fri. - Sun. Backpacking Great Smoky Mountain National Park, TN 6/14 $97 30 Sun

  18. First observation and Dalitz analysis of the D-0 -> K-S(0)eta pi(0) decay

    E-Print Network [OSTI]

    Besson, David Zeke

    2004-09-01T23:59:59.000Z

    Using 9.0 fb(-1) of integrated luminosity in e(+)e(-) collisions near the Y(4S) mass collected with the CLEO II.V detector we report the first observation of the decay D-0-->K(S)(0)etapi(0). We measure the ratio of branching fractions, BR(D-0-->K...

  19. Degenerate Metric Phase Boundaries

    E-Print Network [OSTI]

    Ingemar Bengtsson; Ted Jacobson

    1999-01-23T23:59:59.000Z

    The structure of boundaries between degenerate and nondegenerate solutions of Ashtekar's canonical reformulation of Einstein's equations is studied. Several examples are given of such "phase boundaries" in which the metric is degenerate on one side of a null hypersurface and non-degenerate on the other side. These include portions of flat space, Schwarzschild, and plane wave solutions joined to degenerate regions. In the last case, the wave collides with a planar phase boundary and continues on with the same curvature but degenerate triad, while the phase boundary continues in the opposite direction. We conjecture that degenerate phase boundaries are always null.

  20. Effects of finite volume on the KL-KS mass difference

    E-Print Network [OSTI]

    Christ, Norman H; Martinelli, Guido; Sachrajda, Christopher T

    2015-01-01T23:59:59.000Z

    Phenomena that involve two or more on-shell particles are particularly sensitive to the effects of finite volume and require special treatment when computed using lattice QCD. In this paper we generalize the results of Luescher, and Lellouch and Luescher, which determine the leading order effects of finite volume on the two-particle spectrum and two-particle decay amplitudes to determine the finite-volume effects in the second order mixing of the K0 and anti-K0 states. We extend the methods of Kim, Sachrajda and Sharpe to provide a direct, uniform treatment of these three, related, finite-volume corrections. In particular, the leading, finite-volume corrections to the KL-KS mass difference Delta M_K and the CP violating parameter epsilon_K are determined, including the potentially large effects which can arise from the near degeneracy of the kaon mass and the energy of a finite-volume, two-pion state.

  1. Effects of finite volume on the KL-KS mass difference

    E-Print Network [OSTI]

    Norman H. Christ; Xu Feng; Guido Martinelli; Christopher T. Sachrajda

    2015-04-05T23:59:59.000Z

    Phenomena that involve two or more on-shell particles are particularly sensitive to the effects of finite volume and require special treatment when computed using lattice QCD. In this paper we generalize the results of Luescher, and Lellouch and Luescher, which determine the leading order effects of finite volume on the two-particle spectrum and two-particle decay amplitudes to determine the finite-volume effects in the second order mixing of the K0 and anti-K0 states. We extend the methods of Kim, Sachrajda and Sharpe to provide a direct, uniform treatment of these three, related, finite-volume corrections. In particular, the leading, finite-volume corrections to the KL-KS mass difference Delta M_K and the CP violating parameter epsilon_K are determined, including the potentially large effects which can arise from the near degeneracy of the kaon mass and the energy of a finite-volume, two-pion state.

  2. Infrared features of KS fermion and Wilson fermion in Lattice Landau Gauge QCD

    E-Print Network [OSTI]

    Sadataka Furui; Hideo Nakajima

    2007-03-06T23:59:59.000Z

    The running coupling and the Kugo-Ojima parameter of unquenched lattice Landau gauge are simulated and compared with the continuum theory. Presence of infrared fixed point of $\\alpha_0\\sim 2-2.5$ irrespective of the fermion actions (Wilson fermions and Kogut-Susskind(KS) fermions) in the continuum and in the chiral limit is suggested. Although there exists dependence on the polarization due to asymmetry of the lattice (time axis is longer than spacial axes), the Kugo-Ojima parameter $c$ is consistent with 1. Presence of $1+c_1/q^2$ correction factor in the running coupling depends on the lattice size and the sea quark mass. In the large lattice size and small sea quark mass, $c_1\\sim 2.8$GeV is confirmed. The MILC configuration of $a=0.09$fm suggests also presence of dimension 4 condensates with sign opposite to the dimension 2 condensates. The gluon propagator, the ghost propagator and the running coupling are compared with recent pQCD results including anomalous dimension of fields up to the 4-loop level.

  3. Detection of the secondary eclipse of WASP-10b in the Ks-band

    E-Print Network [OSTI]

    Cruz, Patricia; Lillo-Box, Jorge; Diaz, Marcos; Birkby, Jayne; López-Morales, Mercedes; Hodgkin, Simon; Fortney, Jonathan J

    2014-01-01T23:59:59.000Z

    WASP-10b, a non-inflated hot Jupiter, was discovered around a K-dwarf in a near circular orbit ($\\sim $$0.06$). Since its discovery in 2009, different published parameters for this system have led to a discussion about the size, density, and eccentricity of this exoplanet. In order to test the hypothesis of a circular orbit for WASP-10b, we have observed its secondary eclipse in the Ks-band, where the contribution of planetary light is high enough to be detected from the ground. Observations were performed with the OMEGA2000 instrument at the 3.5-meter telescope at Calar Alto (Almer\\'ia, Spain), in staring mode during 5.4 continuous hours, with the telescope defocused, monitoring the target during the expected secondary eclipse. A relative light curve was generated and corrected from systematic effects, using the Principal Component Analysis (PCA) technique. The final light curve was fitted using a transit model to find the eclipse depth and a possible phase shift. The best model obtained from the Markov Chai...

  4. Observation of a narrow structure in 1H(?,KS0)X via interference with phi-meson production

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Amaryan, M J; Nepali, C; Polyakov, M V; Azimov, Ya; Briscoe, W J; Dodge, G E; Hyde, C E; Klein, F; Kuznetsov, V; Strakovsky, I

    2012-03-21T23:59:59.000Z

    We report observation of a narrow peak structure at ?1.54 GeV with a Gaussian width ? = 6 MeV in the missing mass of KS in the reaction ? + p ? pKSKL. The observed structure may be due to the interference between a strange (or antistrange) baryon resonance in the pKL system and the ?(KSKL) photoproduction leading to the same final state. The statistical significance of the observed excess of events estimated as the log-likelihood ratio of the resonant signal + background hypothesis and the ?-production-based background-only hypothesis corresponds to 5.3?.

  5. Boundaries and Topological Algorithms

    E-Print Network [OSTI]

    Fleck, Margaret Morrison

    1988-09-01T23:59:59.000Z

    This thesis develops a model for the topological structure of situations. In this model, the topological structure of space is altered by the presence or absence of boundaries, such as those at the edges of objects. ...

  6. Inclusive production of $\\Lambda$, $K^0_s$ and exotic narrow resonances for systems $K_s^0 p$, $K_s^0 \\Lambda$, $\\Lambda p$ from p+propane interactions at 10 GeV/c

    E-Print Network [OSTI]

    Aslanyan, P Z

    2005-01-01T23:59:59.000Z

    Experimental data from the 2m propane bubble chamber for production of $\\Lambda$, $K^0_s$ have been used to search of exotic baryon states, in the $K_s^0 p$, $K_s^0 \\Lambda$ and $\\Lambda p$ decay mode for the reaction p+propane at 10 GeV/c. The estimation of experimental inclusive cross sections for $\\Lambda$ and $K^0_s$ production in the p$^{12}C$ collision is equal to $\\sigma_{\\Lambda}$= 13.3$\\pm$1.7 mb and $\\sigma_{K^0_s}$= 3.8$\\pm$0.6 mb, respectively. The measured $\\Lambda /\\pi^+$ ratio from pC reaction is equal to (5.3$\\pm0.8)*10^{-2}$. The experimental $\\Lambda /\\pi^+$ ratio from the pC reaction is approximately two times larger than the $\\Lambda /\\pi^+$ ratio simulated by FRITIOF model from the pC reaction. The invariant mass spectrum $\\Lambda K^0_s$ registered narrow peaks in regions of 1750 and 1795 MeV/$c^2$. The statistical significance of these peaks has been estimated as 5.6 and 3.3 S.D., respectively. These would be candidates for the $N^0$ or the $\\Xi^0$ pentaquark states. The $pK^0_s$ invaria...

  7. Transgressing the Boundaries: An Afterword

    E-Print Network [OSTI]

    Sokal, Alan

    the Boundaries: Toward a Transformative Hermeneutics of Quantum Gravity'', which appeared in Social Text #46

  8. Table 2 -Lime use and practices on Corn, major producing states, 2001 CO GA IL IN IA KS KY MI MN MO NE NY NC ND OH PA SD TX WI Area

    E-Print Network [OSTI]

    Kammen, Daniel M.

    Table 2 - Lime use and practices on Corn, major producing states, 2001 CO GA IL IN IA KS KY MI MN.7 Table 2 - Lime use and practices on Corn, major producing states, 2000 CO IL IN IA KS KY MI MN MO NE NY use and practices on Corn, major producing states, 1999 CO IL IN IA KS KY MI MN MO NE NC OH SD TX WI

  9. Inclusive production of $?$, $K^0_s$ and exotic narrow resonances for systems $K_s^0 p$, $K_s^0 ?$, $?p$ from p+propane interactions at 10 GeV/c

    E-Print Network [OSTI]

    P. Zh. Aslanyan

    2005-11-09T23:59:59.000Z

    Experimental data from the 2m propane bubble chamber for production of $\\Lambda$, $K^0_s$ have been used to search of exotic baryon states, in the $K_s^0 p$, $K_s^0 \\Lambda$ and $\\Lambda p$ decay mode for the reaction p+propane at 10 GeV/c. The estimation of experimental inclusive cross sections for $\\Lambda$ and $K^0_s$ production in the p$^{12}C$ collision is equal to $\\sigma_{\\Lambda}$= 13.3$\\pm$1.7 mb and $\\sigma_{K^0_s}$= 3.8$\\pm$0.6 mb, respectively. The measured $\\Lambda /\\pi^+$ ratio from pC reaction is equal to (5.3$\\pm0.8)*10^{-2}$. The experimental $\\Lambda /\\pi^+$ ratio from the pC reaction is approximately two times larger than the $\\Lambda /\\pi^+$ ratio simulated by FRITIOF model from the pC reaction. The invariant mass spectrum $\\Lambda K^0_s$ registered narrow peaks in regions of 1750 and 1795 MeV/$c^2$. The statistical significance of these peaks has been estimated as 5.6 and 3.3 S.D., respectively. These would be candidates for the $N^0$ or the $\\Xi^0$ pentaquark states. The $pK^0_s$ invariant mass spectrum shows resonant structures with $M_{K_s^0 p}$=1540, 1613, 1821 MeV/$c^2$. The statistical significance of these peaks have been estimated as 5.5,4.8 and 5.0 s.d., respectively. The invariant mass spectrum S=-1 $\\Lambda p$ observed a narrow peaks at 2100, 2175,2285 and 2353 MeV/$c^2$. Their excess above background by the second method is 6.9, 4.9, 3.8 and 2.9 S.D., respectively.

  10. RELAP5/MOD3.2 Assessment Using CHF Data from the KS-1 and V-200 Experiment Facilities

    SciTech Connect (OSTI)

    Bayless, Paul David

    2001-07-01T23:59:59.000Z

    The RELAP/MOD3.2 computer code has been assessed using rod bundle critical heat flux data from the KS-1 and V-200 facilities. This work was performed as part of the U.S. Department of Energy’s International Nuclear Safety Program, and is part of the effort addressing the capability of the RELAP5/MOD3.2 code to model transients in Soviet-designed reactors. Designated VVER Standard Problem 7, these tests addressed one of the important phenomena related to VVER behavior that the code needs to simulate well, core heat transfer. The code was judged to be in minimal agreement with the experiment data, consistently overpredicting the measured critical heat flux. It is recommended that a model development effort be undertaken to develop a critical heat flux model for RELAP5 that better represents the behavior in VVER rod bundles.

  11. Isospin analysis of Theta+ production forbids gamma p ---> Theta+ K(s) and allows gamma n ---> Theta+ K-.

    E-Print Network [OSTI]

    Karliner, Marek; Lipkin, Harry J

    ar X iv :h ep -p h/ 05 06 08 4v 3 1 6 Ju n 20 05 Cavendish-HEP-05/09 TAUP 2807/05 ANL-HEP-PR-05-47 Isospin Analysis of ?+ production forbids ?p ? ?+ Ks and allows ?n ? ?+ K? Marek Karliner a,b? and Harry J. Lipkin b,c† a Cavendish Laboratory... .g. comparing ?p ? pK+K? with the analogous reaction with neutral kaons in the final state. One can also do an analogous comparison in ?d. The relevant data might in principle be available in the CLAS g11 and LEPS experiments. We also note that the ?KoK¯o vertex...

  12. Structure of Bright 2MASS Galaxies: 2D Fits to the Ks-band Surface Brightness Profiles

    E-Print Network [OSTI]

    Daniel H. McIntosh; Ari H. Maller; Neal Katz; Martin D. Weinberg

    2002-09-01T23:59:59.000Z

    The unprecedented sky coverage and photometric uniformity of the Two Micron All Sky Survey (2MASS) provides a rich resource for obtaining a detailed understanding of the galaxies populating our local (z<0.1) Universe. A full characterization of the physical structure of nearby galaxies is essential for theoretical and observational studies of galaxy evolution and structure formation. We have begun a quantified description of the internal structure and morphology of 10,000 bright (10<Ks<11) 2MASS galaxies through multi-component model fits to the 2D surface brightness profiles using GIM2D. From our initial Monte Carlo tests on 77 galaxies drawn at random from the RC3, we find that the model derived structural parameter errors due to sky uncertainies are typically less than 10%.

  13. Boundary transfer matrices and boundary quantum KZ equations

    E-Print Network [OSTI]

    Bart Vlaar

    2014-10-31T23:59:59.000Z

    A simple relation between inhomogeneous transfer matrices and boundary quantum KZ equations is exhibited for quantum integrable systems with reflecting boundary conditions, analogous to an observation by Gaudin for periodic systems. Thus the boundary quantum KZ equations receive a new motivation. We also derive the commutativity of Sklyanin's boundary transfer matrices by merely imposing appropriate reflection equations, i.e. without using the conditions of crossing symmetry and unitarity of the R-matrix.

  14. Boundary streaming with Navier boundary condition Jin-Han Xiea)

    E-Print Network [OSTI]

    Vanneste, Jacques

    is the fluid's kinematic shear viscosity and is the wave's angular frequency. In water, and for frequencies applications involving high-frequency acoustic waves over a solid boundary, the Stokes boundary-layer thickness to travelling and standing waves shows that the boundary slip respectively increases and decreases the streaming

  15. Boundary unitarity without firewalls

    E-Print Network [OSTI]

    Ted Jacobson

    2014-03-23T23:59:59.000Z

    Both AdS/CFT duality and more general reasoning from quantum gravity point to a rich collection of boundary observables that always evolve unitarily. The physical quantum gravity states described by these observables must be solutions of the spatial diffeomorphism and Wheeler-deWitt constraints, which implies that the state space does not factorize into a tensor product of localized degrees of freedom. The "firewall" argument that unitarity of black hole S-matrix implies the presence of a highly excited quantum state near the horizon is based on such a factorization, hence is not applicable in quantum gravity. In fact, there appears to be no conflict between boundary unitarity and regularity of the event horizon.

  16. 56 PM NETWORK june 2012 WWW.PMI.ORG by MIchEllE bOWlEs JacKsON

    E-Print Network [OSTI]

    Chapman, Michael S.

    56 PM NETWORK june 2012 WWW.PMI.ORG by MIchEllE bOWlEs JacKsON stepby #12;june 2012 PM NETWORK 57 by adopting an iterative 58 PM NETWORK june 2012 WWW.PMI.ORG waterfall approach. This introduced the idea

  17. Business Career Services Center | 1300 Sunnyside Ave. Rm. 125 | Lawrence, KS 66045 | (785) 864-5591 | www.business.ku.edu

    E-Print Network [OSTI]

    Business Career Services Center | 1300 Sunnyside Ave. Rm. 125 | Lawrence, KS 66045 | (785) 864-5591 | www.business.ku.edu - 1 - What Can I Do With A Major In INFORMATION SYSTEMS? This handout will provide education. You'll gain a solid foundation in the various business disciplines and gain an understanding

  18. ENTROPY BOUNDARY LAYERS FRANCK SUEUR

    E-Print Network [OSTI]

    Sueur, Franck

    on the boundary. These conditions are used in a reduction of the system. We construct BKW expansions at all order

  19. Boundaries on Spacetimes: An Outline

    E-Print Network [OSTI]

    Steven G. Harris

    2003-10-15T23:59:59.000Z

    The causal boundary construction of Geroch, Kronheimer, and Penrose has some universal properties of importance for general studies of spacetimes, particularly when equipped with a topology derived from the causal structure. Properties of the causal boundary are detailed for spacetimes with spacelike boundaries, for multi-warped spacetimes, for static spacetimes, and for spacetimes with group actions.

  20. Topology of the Future Chronological Boundary: Universality for Spacelike Boundaries

    E-Print Network [OSTI]

    Steven G. Harris

    1999-07-19T23:59:59.000Z

    A method is presented for imputing a topology for any chronological set, i.e., a set with a chronology relation, such as a spacetime or a spacetime with some sort of boundary. This topology is shown to have several good properties, such as replicating the manifold topology for a spacetime and replicating the expected topology for some simple examples of spacetime-with-boundary; it also allows for a complete categorical characterization, in topological categories, of the Future Causal Boundary construction of Geroch, Kronheimer, and Penrose, showing that construction to have a universal property for future-completing chronological sets with spacelike boundaries. Rigidity results are given for any reasonable future completion of a spacetime, in terms of the GKP boundary: In the imputed topology, any such boundary must be homeomorphic to the GKP boundary (if all points have indecomposable pasts) or to a topological quotient of a closely related boundary (if boundaries are spacelike). A large class of warped-product-type spacetimes with spacelike boundaries is examined, calculating the GKP and other possible boundaries, and showing that the imputed topology gives expected results; included among these are the Schwarzschild singularity and those Robertson-Walker singularities which are spacelike.

  1. ARM - SGP Boundary Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC :ProductsSCM Forcing Data DerivedInstrumentsPolar YearResearchBoundary

  2. 2. System boundaries; Balance equations

    E-Print Network [OSTI]

    Zevenhoven, Ron

    ;5/28 Systems and boundaries /3 An isolated system is a special kind of closed system Pictures: KJ05 Q = heat W Example: an electric hot water heater in a house ­ The electric heater is a closed system ­ The water1/28 2. System boundaries; Balance equations Ron Zevenhoven �bo Akademi University Thermal and flow

  3. 8, 88178846, 2008 Observed boundary-

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 8, 8817­8846, 2008 Observed boundary- layer/mesoscale impacts on Saharan dust J. H. Marsham et and Enviroment, University of Leeds, Leeds, UK 2 Institut f¨ur Meteorologie und Klimaforschung, Universit@env.leeds.ac.uk) 8817 #12;ACPD 8, 8817­8846, 2008 Observed boundary- layer/mesoscale impacts on Saharan dust J. H

  4. Print http://us.mg4.mail.yahoo.com/neo/launch?.rand=deOsgk04ks40i Subject: RE: [s-w-h] b Solar verses wind efficiency

    E-Print Network [OSTI]

    .yahoo.com/neo/launch?.rand=deOsgk04ks40i Subject: RE: [s-w-h] b Solar verses wind efficiency From: Michael Klemen (wind4energy;Print http://us.rng4.mail.yahoo.comlneo/launch?.rand=deOsgko4ks4 energy in the wind is proportional://www.ndsu.edu/ndsu/klemen/Perfect_Turbine.htm You can see that for an ideal real life wind turbine ("good turbine") the increase in energy

  5. South Campus Boundary/Landscape

    E-Print Network [OSTI]

    Brownstone, Rob

    South Campus Boundary/Landscape April 18, 2012 #12;#12;7:00 - 7:05 Introductions and Review of the Agenda 7:05 - 7:20 Principles of the South Campus Boundary/Landscape from the Feb 21 Design Charette 7:20 - 7:30 Landscape Examples 7:30 - 7:45 Concepts and Ideas for LeMarchant St. 7:45 - 7:50 Break

  6. Changing the Structure Boundary Geometry

    SciTech Connect (OSTI)

    Karasev, Viktor; Dzlieva, Elena; Ivanov, Artyom [St.-Petersburg State University, Physics Faculty, Ulianovskaya 1, Peterhof, St. Petersburg, 198504 (Russian Federation)

    2008-09-07T23:59:59.000Z

    Analysis of previously obtained results shows that hexagonal crystal lattice is the dominant type of ordering, in particular, in striated glow discharges. We explore the possibility for changing the dust distribution in horizontal cross sections of relatively highly ordered structures in a glow-discharge. Presuming that boundary geometry can affect dust distribution, we used cylindrical coolers held at 0 deg. C and placed against a striation containing a structure, to change the geometry of its outer boundary. By varying the number of coolers, their positions, and their separations from the tube wall, azimuthally asymmetric thermophoretic forces can be used to form polygonal boundaries and vary the angles between their segments (in a horizontal cross section). The corner in the structure's boundary of 60 deg. stimulates formation of hexagonal cells. The structure between the supported parallel boundaries is also characterized by stable hexagonal ordering. We found that a single linear boundary segment does not give rise to any sizable domain, but generates a lattice extending from the boundary (without edge defects). A square lattice can be formed by setting the angle equal to 90 deg. . However, angles of 45 deg. and 135 deg. turned out easier to form. Square lattice was created by forming a near-135 deg. corner with four coolers. It was noted that no grain ordering is observed in the region adjacent to corners of angles smaller than 30 deg. , which do not promote ordering into cells of any shape. Thus, manipulation of a structure boundary can be used to change dust distribution, create structures free of the ubiquitous edge defects that destroy orientation order, and probably change the crystal lattice type.

  7. Lagrangian Variational Framework for Boundary Value Problems

    E-Print Network [OSTI]

    Alexander Figotin; Guillermo Reyes

    2014-07-29T23:59:59.000Z

    A boundary value problem is commonly associated with constraints imposed on a system at its boundary. We advance here an alternative point of view treating the system as interacting "boundary" and "interior" subsystems. This view is implemented through a Lagrangian framework that allows to account for (i) a variety of forces including dissipative acting at the boundary; (ii) a multitude of features of interactions between the boundary and the interior fields when the boundary fields may differ from the boundary limit of the interior fields; (iii) detailed pictures of the energy distribution and its flow; (iv) linear and nonlinear effects. We provide a number of elucidating examples of the structured boundary and its interactions with the system interior. We also show that the proposed approach covers the well known boundary value problems.

  8. Beyond the no-slip boundary condition

    E-Print Network [OSTI]

    Brenner, Howard

    This paper offers a simple macroscopic approach to the question of the slip boundary condition to be imposed upon the tangential component of the fluid velocity at a solid boundary. Plausible reasons are advanced for ...

  9. SLE($?,?$)and Boundary Coulomb Gas

    E-Print Network [OSTI]

    S. Moghimi-Araghi; M. A. Rajabpour; S. Rouhani

    2005-08-07T23:59:59.000Z

    We consider the coulomb gas model on the upper half plane with different boundary conditions, namely Drichlet, Neuman and mixed. We related this model to SLE($\\kappa,\\rho$) theories. We derive a set of conditions connecting the total charge of the coulomb gas, the boundary charges, the parameters $\\kappa$ and $\\rho$. Also we study a free fermion theory in presence of a boundary and show with the same methods that it would lead to logarithmic boundary changing operators.

  10. Stability of titanium oxide phases in Kohn-Sham density functional A well known problem in practical Kohn-Sham (KS) density functional theory (DFT) calculations is that it yields the wrong order of

    E-Print Network [OSTI]

    Bjørnstad, Ottar Nordal

    Stability of titanium oxide phases in Kohn-Sham density functional theory A well known problem in practical Kohn-Sham (KS) density functional theory (DFT) calculations is that it yields the wrong order-DFT, but with different levels of corrections to the exchange-correlation functional. Kohn-Sham density functional theory

  11. Universality of the Future Chronological Boundary

    E-Print Network [OSTI]

    Steven G. Harris

    1997-04-04T23:59:59.000Z

    The purpose of this note is to establish, in a categorical manner, the universality of the Geroch-Kronheimer-Penrose causal boundary when considering the types of causal structures that may profitably be put on any sort of boundary for a spacetime. Actually, this can only be done for the future causal boundary (or the past causal boundary) separately; furthermore, only the chronology relation, not the causality relation, is considered, and the GKP topology is eschewed. The final result is that there is a unique map, with the proper causal properties, from the future causal boundary of a spacetime onto any ``reasonable" boundary which supports some sort of chronological structure and which purports to consist of a future completion of the spacetime. Furthermore, the future causal boundary construction is categorically unique in this regard.

  12. Geometric Boundary Data for the Gravitational Field

    E-Print Network [OSTI]

    H-O. Kreiss; J. Winicour

    2014-02-25T23:59:59.000Z

    An outstanding issue in the treatment of boundaries in general relativity is the lack of a local geometric interpretation of the necessary boundary data. For the Cauchy problem, the initial data is supplied by the 3-metric and extrinsic curvature of the initial Cauchy hypersurface.. This Cauchy data determines a solution to Einstein's equations which is unique up to a diffeomorphism. Here, we show how three pieces of boundary data, which are associated locally with the geometry of the boundary, likewise determine a solution of the initial-boundary value problem which is unique up to a diffeomorphism. One piece of this data, constructed from the extrinsic curvature of the boundary, determines the dynamical evolution of the boundary. The other two pieces constitute a conformal class of rank-2, positive definite metrics, which represent the two gravitational degrees of freedom.

  13. Shaping Environmental Justice: Applying Science, Technology, and Society Boundary Work

    E-Print Network [OSTI]

    Huang, Chih-Tung

    2012-01-01T23:59:59.000Z

    Applying Science, Technology and Society Boundary Work Chih-the STS (Science, Technology and Society) study as boundary-

  14. Moment problems and boundaries of number triangles

    E-Print Network [OSTI]

    Gnedin, Alexander

    2008-01-01T23:59:59.000Z

    The boundary problem for graphs like Pascal's but with general multiplicities of edges is related to a `backward' problem of moments of the Hausdorff type.

  15. Performance Boundaries in Nb3Sn Superconductors

    E-Print Network [OSTI]

    Godeke, Arno

    2006-01-01T23:59:59.000Z

    Boundaries in Nb 3 Sn Superconductors – Berkeley, CABoundaries in Nb 3 Sn Superconductors – Berkeley, CABoundaries in Nb 3 Sn Superconductors Arno Godeke Berkeley,

  16. Casimir pistons with hybrid boundary conditions

    E-Print Network [OSTI]

    Xiang-hua Zhai; Xin-zhou Li

    2007-04-30T23:59:59.000Z

    The Casimir effect giving rise to an attractive or repulsive force between the configuration boundaries that confine the massless scalar field is reexamined for one to three-dimensional pistons in this paper. Especially, we consider Casimir pistons with hybrid boundary conditions, where the boundary condition on the piston is Neumann and those on other surfaces are Dirichlet. We show that the Casimir force on the piston is always repulsive, in contrast with the same problem where the boundary conditions are Dirichlet on all surfaces.

  17. Prediction Error and Event Boundaries 1 Running Head: PREDICTION ERROR AND EVENT BOUNDARIES

    E-Print Network [OSTI]

    Zacks, Jeffrey M.

    Prediction Error and Event Boundaries 1 Running Head: PREDICTION ERROR AND EVENT BOUNDARIES A computational model of event segmentation from perceptual prediction. Jeremy R. Reynolds, Jeffrey M. Zacks, and Todd S. Braver Washington University Manuscript #12;Prediction Error and Event Boundaries 2 People tend

  18. Green's functions for Neumann boundary conditions

    E-Print Network [OSTI]

    Jerrold Franklin

    2012-08-27T23:59:59.000Z

    Green's functions for Neumann boundary conditions have been considered in Math Physics and Electromagnetism textbooks, but special constraints and other properties required for Neumann boundary conditions have generally not been noticed or treated correctly. In this paper, we derive an appropriate Neumann Green's function with these constraints and properties incorporated.

  19. Cherokee Clitics: The Word Boundary Problem

    E-Print Network [OSTI]

    Haag, Marcia

    1999-01-01T23:59:59.000Z

    The problem of identifying Cherokee clitics is complicated by the fact that the prosodic word, marked by the presence of a tonal boundary, may not match the morphological word. Clitics may or may not respect the the word boundary as marked by tone...

  20. Cyclone separator having boundary layer turbulence control

    DOE Patents [OSTI]

    Krishna, Coimbatore R. (Mt. Sinai, NY); Milau, Julius S. (Port Jefferson, NY)

    1985-01-01T23:59:59.000Z

    A cyclone separator including boundary layer turbulence control that is operable to prevent undue build-up of particulate material at selected critical areas on the separator walls, by selectively varying the fluid pressure at those areas to maintain the momentum of the vortex, thereby preventing particulate material from inducing turbulence in the boundary layer of the vortical fluid flow through the separator.

  1. New boundary conditions for granular fluids

    E-Print Network [OSTI]

    Mark D. Shattuck

    2007-03-22T23:59:59.000Z

    We present experimental evidence, which contradicts the the standard boundary conditions used in continuum theories of non-cohesive granular flows for the velocity normal to a boundary u.n=0, where n points into the fluid. We propose and experimentally verify a new boundary condition for u.n, based on the observation that the boundary cannot exert a tension force Fb on the fluid. The new boundary condition is u.n=0 if Fb.n>=0 else n.P.n=0, where P is the pressure tensor. This is the analog of cavitation in ordinary fluids, but due the lack of attractive forces and dissipation it occurs frequently in granular flows.

  2. From Neuman to Dirichlet boundary conditions

    SciTech Connect (OSTI)

    Nikolic, B.; Sazdovic, B. [Institute of Physics, 11001 Belgrade, P.O.Box 57 (Serbia and Montenegro)

    2007-04-23T23:59:59.000Z

    The Dirichlet boundary conditions for the end-point of the open string define Dp-brane. It is parameterized by the rest of coordinates, with Neuman boundary conditions. The relations between background fields can produce the local gauge symmetries of the world-sheet action. After gauge fixing, some Neuman boundary conditions turn into the Dirichlet ones, decreasing the number of Dp-brane dimensions. The physical Dp-brane is gauge invariant part of the initial one. The gauge invariant coordinates are expressed as linear combinations of the effective coordinates and momenta. This fact explains the origin of non-commutativity and the existence of commutative Dp-brane coordinates.

  3. Energy transport using natural convection boundary layers

    SciTech Connect (OSTI)

    Anderson, R.

    1986-04-01T23:59:59.000Z

    Natural convection is one of the major modes of energy transport in passive solar buildings. There are two primary mechanisms for natural convection heat transport through an aperture between building zones: (1) bulk density differences created by temperature differences between zones; and (2) thermosyphon pumping created by natural convection boundary layers. The primary objective of the present study is to compare the characteristics of bulk density driven and boundary layer driven flow, and discuss some of the advantages associated with the use of natural convection boundary layers to transport energy in solar building applications.

  4. Topological analysis of the grain boundary space

    E-Print Network [OSTI]

    Patala, Srikanth

    2011-01-01T23:59:59.000Z

    Grain boundaries and their networks have a profound influence on the functional and structural properties of every class of polycrystalline materials and play a critical role in structural evolution and phase transformations. ...

  5. Brownian walkers within subdiffusing territorial boundaries

    E-Print Network [OSTI]

    Luca Giuggioli; Jonathan R. Potts; Stephen Harris

    2011-02-04T23:59:59.000Z

    Inspired by the collective phenomenon of territorial emergence, whereby animals move and interact through the scent marks they deposit, we study the dynamics of a 1D Brownian walker in a random environment consisting of confining boundaries that are themselves diffusing anomalously. We show how to reduce, in certain parameter regimes, the non-Markovian, many-body problem of territoriality to the analytically tractable one-body problem studied here. The mean square displacement (MSD) of the 1D Brownian walker within subdiffusing boundaries is calculated exactly and generalizes well known results when the boundaries are immobile. Furthermore, under certain conditions, if the boundary dynamics are strongly subdiffusive, we show the appearance of an interesting non-monotonicity in the time dependence of the MSD, giving rise to transient negative diffusion.

  6. Nonlinear boundary value problem of magnetic insulation

    E-Print Network [OSTI]

    A. V. Sinitsyn

    2000-09-09T23:59:59.000Z

    On the basis of generalization of upper and lower solution method to the singular two point boundary value problems, the existence theorem of solutions for the system, which models a process of magnetic insulation in plasma is proved.

  7. Effects of Transition Metals on the Grain Boundary Cohesion in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transition Metals on the Grain Boundary Cohesion in Tungsten. Effects of Transition Metals on the Grain Boundary Cohesion in Tungsten. Abstract: We report on the effects of...

  8. antarctic boundary layer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Geosciences Websites Summary: Boundary Layer Meteorology (METR 5103) Spring 2014 Syllabus General information Fundamentals of the atmospheric boundary layer dynamics and...

  9. atmosperic boundary layer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Geosciences Websites Summary: Boundary Layer Meteorology (METR 5103) Spring 2014 Syllabus General information Fundamentals of the atmospheric boundary layer dynamics and...

  10. Friction of Steel Sliding Under Boundary Lubrication Regime in...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Friction of Steel Sliding Under Boundary Lubrication Regime in Commercial Gear Oils at Elevated Temperatures Friction of Steel Sliding Under Boundary Lubrication Regime in...

  11. Incorporating local boundary conditions into nonlocal theories

    E-Print Network [OSTI]

    Burak Aksoylu; Horst Reinhard Beyer; Fatih Celiker

    2014-11-12T23:59:59.000Z

    We study nonlocal equations from the area of peridynamics on bounded domains. In our companion paper, we discover that, on $\\mathbb{R}^n$, the governing operator in peridynamics, which involves a convolution, is a bounded function of the classical (local) governing operator. Building on this, we define an abstract convolution operator on bounded domains. The abstract convolution operator is a function of the classical operator, defined by a Hilbert basis available due to the purely discrete spectrum of the latter. As governing operator of the nonlocal equation we use a function of the classical operator, this allows us to incorporate local boundary conditions into nonlocal theories. For the homogeneous wave equation with the considered boundary conditions, we prove that continuity is preserved by time evolution. We give explicit solution expressions for the initial value problems with prominent boundary conditions such as periodic, antiperiodic, Neumann, and Dirichlet. In order to connect to the standard convolution, we give an integral representation of the abstract convolution operator. We present additional "simple" convolutionsbased on periodic and antiperiodic boundary conditions that lead Neumann and Dirichlet boundary conditions. We present a numerical study of the solutions of the wave equation. For discretization, we employ a weak formulation based on a Galerkin projection and use piecewise polynomials on each element which allows discontinuities of the approximate solution at the element borders. We study convergence order of solutions with respect to polynomial order and observe optimal convergence. We depict the solutions for each boundary condition.

  12. Metal precipitation at grain boundaries in silicon: Dependence on grain boundary character and dislocation decoration

    E-Print Network [OSTI]

    are combined to determine the dependence of metal silicide precipitate formation on grain boundary character and microstructure in multicrystalline silicon mc-Si . Metal silicide precipitate decoration is observed to increase the local metal silicide precipitate concentrations at various types of grain boundaries, identifying clear

  13. Surface and grain boundary scattering in nanometric Cu thin films: A quantitative analysis including twin boundaries

    SciTech Connect (OSTI)

    Barmak, Katayun [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 and Department of Materials Science and Engineering and Materials Research Science and Engineering Center, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Darbal, Amith [Department of Materials Science and Engineering and Materials Research Science and Engineering Center, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Ganesh, Kameswaran J.; Ferreira, Paulo J. [Materials Science and Engineering, The University of Texas at Austin, 1 University Station, Austin, Texas 78712 (United States); Rickman, Jeffrey M. [Department of Materials Science and Engineering and Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States); Sun, Tik; Yao, Bo; Warren, Andrew P.; Coffey, Kevin R., E-mail: kb2612@columbia.edu [Department of Materials Science and Engineering, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816 (United States)

    2014-11-01T23:59:59.000Z

    The relative contributions of various defects to the measured resistivity in nanocrystalline Cu were investigated, including a quantitative account of twin-boundary scattering. It has been difficult to quantitatively assess the impact twin boundary scattering has on the classical size effect of electrical resistivity, due to limitations in characterizing twin boundaries in nanocrystalline Cu. In this study, crystal orientation maps of nanocrystalline Cu films were obtained via precession-assisted electron diffraction in the transmission electron microscope. These orientation images were used to characterize grain boundaries and to measure the average grain size of a microstructure, with and without considering twin boundaries. The results of these studies indicate that the contribution from grain-boundary scattering is the dominant factor (as compared to surface scattering) leading to enhanced resistivity. The resistivity data can be well-described by the combined Fuchs–Sondheimer surface scattering model and Mayadas–Shatzkes grain-boundary scattering model using Matthiessen's rule with a surface specularity coefficient of p?=?0.48 and a grain-boundary reflection coefficient of R?=?0.26.

  14. Do grain boundaries in nanophase metals slide?

    SciTech Connect (OSTI)

    Bringa, E M; Leveugle, E; Caro, A

    2006-10-27T23:59:59.000Z

    Nanophase metallic materials show a maximum in strength as grain size decreases to the nano scale, indicating a break down of the Hall-Petch relation. Grain boundary sliding, as a possible accommodation mechanisms, is often the picture that explain computer simulations results and real experiments. In a recent paper, Bringa et al. Science 309, 1838 (2005), we report on the observation of an ultra-hard behavior in nanophase Cu under shock loading, explained in terms of a reduction of grain boundary sliding under the influence of the shock pressure. In this work we perform a detailed study of the effects of hydrostatic pressure on nanophase Cu plasticity and find that it can be understood in terms of pressure dependent grain boundary sliding controlled by a Mohr-Coulomb law.

  15. Wireless boundary monitor system and method

    DOE Patents [OSTI]

    Haynes, Howard D. (Knoxville, TN); Ayers, Curtis W. (Kingston, TN)

    1997-01-01T23:59:59.000Z

    A wireless boundary monitor system used to monitor the integrity of a boundary surrounding an area uses at least two housings having at least one transmitting means for emitting ultrasonic pressure waves to a medium. Each of the housings has a plurality of receiving means for sensing the pressure waves in the medium. The transmitting means and the receiving means of each housing are aimable and communicably linked. At least one of the housings is equipped with a local alarm means for emitting a first alarm indication whereby, when the pressure waves propagating from a transmitting means to a receiving means are sufficiently blocked by an object a local alarm means or a remote alarm means or a combination thereof emit respective alarm indications. The system may be reset either manually or automatically. This wireless boundary monitor system has useful applications in both indoor and outdoor environments.

  16. Casimir Pistons with General Boundary Conditions

    E-Print Network [OSTI]

    Guglielmo Fucci

    2014-10-16T23:59:59.000Z

    In this work we analyze the Casimir energy and force for a scalar field endowed with general self-adjoint boundary conditions propagating in a higher dimensional piston configuration. The piston is constructed as a direct product $I\\times N$, with $I=[0,L]\\subset\\mathbb{R}$ and $N$ a smooth, compact Riemannian manifold with or without boundary. The study of the Casimir energy and force for this configuration is performed by employing the spectral zeta function regularization technique. The obtained analytic results depend explicitly on the spectral zeta function associated with the manifold $N$ and the parameters describing the general boundary conditions imposed. These results are then specialized to the case in which the manifold $N$ is a $d$-dimensional sphere.

  17. Wireless boundary monitor system and method

    DOE Patents [OSTI]

    Haynes, H.D.; Ayers, C.W.

    1997-12-09T23:59:59.000Z

    A wireless boundary monitor system used to monitor the integrity of a boundary surrounding an area uses at least two housings having at least one transmitting means for emitting ultrasonic pressure waves to a medium. Each of the housings has a plurality of receiving means for sensing the pressure waves in the medium. The transmitting means and the receiving means of each housing are aimable and communicably linked. At least one of the housings is equipped with a local alarm means for emitting a first alarm indication whereby, when the pressure waves propagating from a transmitting means to a receiving means are sufficiently blocked by an object a local alarm means or a remote alarm means or a combination thereof emit respective alarm indications. The system may be reset either manually or automatically. This wireless boundary monitor system has useful applications in both indoor and outdoor environments. 4 figs.

  18. TURBULENCE IN SUPERSONIC AND HYPERSONIC BOUNDARY LAYERS

    E-Print Network [OSTI]

    Martín, Pino

    TURBULENCE IN SUPERSONIC AND HYPERSONIC BOUNDARY LAYERS Alexander J. Smits and M. Pino Martin in supersonic and hypersonic flow where the effects of compressibility have a direct influence on the turbulence. Experimental and DNS results are presented and compared. Key words: Turbulence, supersonic, hypersonic, shocks

  19. 1. Integrated Database 2. Boundary Analysis

    E-Print Network [OSTI]

    1. Integrated Database 2. Boundary Analysis Melinda Laituri Colorado State University June 2011 #12 data Model package/ Analysis technique #12;Establishing a Database What are our scales? What are our units of analysis? What commonality do we have? What is the nature of our data? What

  20. Planetary Boundary Layer from AERI and MPL

    SciTech Connect (OSTI)

    Sawyer, Virginia

    2014-02-13T23:59:59.000Z

    The distribution and transport of aerosol emitted to the lower troposphere is governed by the height of the planetary boundary layer (PBL), which limits the dilution of pollutants and influences boundary-layer convection. Because radiative heating and cooling of the surface strongly affect the PBL top height, it follows diurnal and seasonal cycles and may vary by hundreds of meters over a 24-hour period. The cap the PBL imposes on low-level aerosol transport makes aerosol concentration an effective proxy for PBL height: the top of the PBL is marked by a rapid transition from polluted, well-mixed boundary-layer air to the cleaner, more stratified free troposphere. Micropulse lidar (MPL) can provide much higher temporal resolution than radiosonde and better vertical resolution than infrared spectrometer (AERI), but PBL heights from all three instruments at the ARM SGP site are compared to one another for validation. If there is agreement among them, the higher-resolution remote sensing-derived PBL heights can accurately fill in the gaps left by the low frequency of radiosonde launches, and thus improve model parameterizations and our understanding of boundary-layer processes.

  1. The Importance of Carbon Footprint Estimation Boundaries

    E-Print Network [OSTI]

    Kammen, Daniel M.

    The Importance of Carbon Footprint Estimation Boundaries H . S C O T T M A T T H E W S , C H R I and organizations are pursuing "carbon footprint" projects to estimate their own contributions to global climate change. Protocol definitions from carbon registries help organizations analyze their footprints

  2. New Boundaries | Issue 16 | June 2013 Treatmentandsupport

    E-Print Network [OSTI]

    Anderson, Jim

    industries with their development of the strongest, lightest material. Moving from the work our engineers about contemporary society, on page 22. For more research stories, visit our website www cells that form part of the human immune system) attacking a cancer cell #12;NewBoundaries|June2013

  3. Planetary Boundary Layer from AERI and MPL

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sawyer, Virginia

    The distribution and transport of aerosol emitted to the lower troposphere is governed by the height of the planetary boundary layer (PBL), which limits the dilution of pollutants and influences boundary-layer convection. Because radiative heating and cooling of the surface strongly affect the PBL top height, it follows diurnal and seasonal cycles and may vary by hundreds of meters over a 24-hour period. The cap the PBL imposes on low-level aerosol transport makes aerosol concentration an effective proxy for PBL height: the top of the PBL is marked by a rapid transition from polluted, well-mixed boundary-layer air to the cleaner, more stratified free troposphere. Micropulse lidar (MPL) can provide much higher temporal resolution than radiosonde and better vertical resolution than infrared spectrometer (AERI), but PBL heights from all three instruments at the ARM SGP site are compared to one another for validation. If there is agreement among them, the higher-resolution remote sensing-derived PBL heights can accurately fill in the gaps left by the low frequency of radiosonde launches, and thus improve model parameterizations and our understanding of boundary-layer processes.

  4. Metal precipitation at grain boundaries in silicon: Dependence on grain boundary character and dislocation decoration

    SciTech Connect (OSTI)

    Buonassisi, T.; Istratov, A. A.; Pickett, M. D.; Marcus, M. A.; Ciszek, T. F.; Weber, E. R. [Department of Materials Science and Engineering, University of California, Berkeley, California 94720 and Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Department of Materials Science and Engineering, University of California, Berkeley, California 94720 and Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2006-07-24T23:59:59.000Z

    Synchrotron-based analytical microprobe techniques, electron backscatter diffraction, and defect etching are combined to determine the dependence of metal silicide precipitate formation on grain boundary character and microstructure in multicrystalline silicon (mc-Si). Metal silicide precipitate decoration is observed to increase with decreasing atomic coincidence within the grain boundary plane (increasing {sigma} values). A few low-{sigma} boundaries contain anomalously high metal precipitate concentrations, concomitant with heavy dislocation decoration. These results provide direct experimental evidence that the degree of interaction between metals and structural defects in mc-Si can vary as a function of microstructure, with implications for mc-Si device performance and processing.

  5. Integrable Boundaries, Conformal Boundary Conditions and A-D-E Fusion Rules

    E-Print Network [OSTI]

    Roger E. Behrend; Paul A. Pearce; Jean-Bernard Zuber

    1998-07-20T23:59:59.000Z

    The $sl(2)$ minimal theories are labelled by a Lie algebra pair $(A,G)$ where $G$ is of $A$-$D$-$E$ type. For these theories on a cylinder we conjecture a complete set of conformal boundary conditions labelled by the nodes of the tensor product graph $A\\otimes G$. The cylinder partition functions are given by fusion rules arising from the graph fusion algebra of $A\\otimes G$. We further conjecture that, for each conformal boundary condition, an integrable boundary condition exists as a solution of the boundary Yang-Baxter equation for the associated lattice model. The theory is illustrated using the $(A_4,D_4)$ or 3-state Potts model.

  6. Nuclear Power Plant Containment Pressure Boundary Research

    SciTech Connect (OSTI)

    Cherry, J.L.; Chokshi, N.C.; Costello, J.F.; Ellingwood, B.R.; Naus, D.J.

    1999-09-15T23:59:59.000Z

    Research to address aging of the containment pressure boundary in light-water reactor plants is summarized. This research is aimed at understanding the significant factors relating occurrence of corrosion, efficacy of inspection, and structural capacity reduction of steel containment and liners of concrete containment. This understanding will lead to improvements in risk-informed regulatory decision making. Containment pressure boundary components are described and potential aging factors identified. Quantitative tools for condition assessments of aging structures to maintain an acceptable level of reliability over the service life of the plant are discussed. Finally, the impact of aging (i.e., loss of shell thickness due to corrosion) on steel containment fragility for a pressurized water reactor ice-condenser plant is presented.

  7. Viscous drag reduction in boundary layers

    SciTech Connect (OSTI)

    Bushnell, D.M.; Hefner, J.N.

    1990-01-01T23:59:59.000Z

    The present volume discusses the development status of stability theory for laminar flow control design, applied aspects of laminar-flow technology, transition delays using compliant walls, the application of CFD to skin friction drag-reduction, active-wave control of boundary-layer transitions, and such passive turbulent-drag reduction methods as outer-layer manipulators and complex-curvature concepts. Also treated are such active turbulent drag-reduction technique applications as those pertinent to MHD flow drag reduction, as well as drag reduction in liquid boundary layers by gas injection, drag reduction by means of polymers and surfactants, drag reduction by particle addition, viscous drag reduction via surface mass injection, and interactive wall-turbulence control.

  8. Boundary Plasma Turbulence Simulations for Tokamaks

    SciTech Connect (OSTI)

    Xu, X; Umansky, M; Dudson, B; Snyder, P

    2008-05-15T23:59:59.000Z

    The boundary plasma turbulence code BOUT models tokamak boundary-plasma turbulence in a realistic divertor geometry using modified Braginskii equations for plasma vorticity, density (ni), electron and ion temperature (T{sub e}; T{sub i}) and parallel momenta. The BOUT code solves for the plasma fluid equations in a three dimensional (3D) toroidal segment (or a toroidal wedge), including the region somewhat inside the separatrix and extending into the scrape-off layer; the private flux region is also included. In this paper, a description is given of the sophisticated physical models, innovative numerical algorithms, and modern software design used to simulate edge-plasmas in magnetic fusion energy devices. The BOUT code's unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics.

  9. [0268] First Galley Proofs MULTIPLICITIES, BOUNDARY POINTS,

    E-Print Network [OSTI]

    Tam, Tin-Yau

    , multiplicity, extreme point, sharp point, boundary point. c Ð , Zagreb Paper OaM-0268 1 #12;2 W.S. CHEUNG NUMERICAL RANGES WAI-SHUN CHEUNG, XUHUA LIU AND TIN-YAU TAM (Communicated by C.-K. Li) Abstract, XUHUA LIU AND T.Y. TAM Given W(A), Embry [8] introduced M = M (A) := {x Cn : x Ax = x x}. In general

  10. Technology adaptation and boundary management in bona fide virtual groups.

    E-Print Network [OSTI]

    Zhang, Huiyan

    2006-04-12T23:59:59.000Z

    In this research project composed of multiple case studies, I focused on how bona fide virtual groups appropriated multiple media to facilitate group boundary construction and boundary management, which are preconditions of group identity formation...

  11. System Identification and Active Control of a Turbulent Boundary Layer

    E-Print Network [OSTI]

    Rathnasingham, Ruben

    An experimental investigation is made into the active control of the near-wall region of a turbulent boundary layer using a linear control scheme. System identification in the boundary layer provides optimal transfer ...

  12. Thermodynamic stability and implications of anisotropic boundary particles

    E-Print Network [OSTI]

    Siem, Ellen J. (Ellen Jane), 1979-

    2005-01-01T23:59:59.000Z

    (cont.) Generally, a boundary is nonplanar in the neighborhood of an attached particle--even when anisotropic interfacial free energies do not produce faceting-and maintains a icKy = 0 while the boundary particles maintain ...

  13. Grain boundary compositon in NiAl

    SciTech Connect (OSTI)

    Miller, M.K.; Jayaram, R.; Camus, P.P. (Metals and Ceramics Div., Oak Ridge National Lab., Oak Ridge, TN (US))

    1992-02-15T23:59:59.000Z

    The high temperature strength and oxidation resistance of many transition metal aluminides makes these intermetallic materials attractive for high temperature applications. However, these aluminides are generally brittle at low temperatures and this restricts their technological applications. However, these aluminides are generally brittle at low temperatures and this restricts their technological applications. It has been demonstrated that the addition of more than 200 ppm of boron to the L1{sub 2}-ordered Ni{sub 3}Al changes the fracture behavior from intergranular to transgranular and increases the ductility. The B2-ordered NiAl nickel aluminide is particularly attractive because of its low density and high melting temperature. This aluminide also fractures intergranularly at room temperature. However, no improvement in ductility is observed with similar boron additions even though the intergranular fracture is suppressed and there is a significant increase in the yield strength. In this paper, the results of an atom probe field ion microscopy investigation of the compositions of the grain boundaries in undoped and boron-doped NiAl are presented. The suitability of the atom probe field ion microscopy technique for the characterization of boundaries has clearly been demonstrated in many previous investigations including the characterization of boron segregation to grain boundaries and other planar features in Ni{sub 3}Al.

  14. Laminar boundary layers in convective heat transport

    E-Print Network [OSTI]

    Christian Seis

    2012-12-12T23:59:59.000Z

    We study Rayleigh-Benard convection in the high-Rayleigh-number and high-Prandtl-number regime, i.e., we consider a fluid in a container that is exposed to strong heating of the bottom and cooling of the top plate in the absence of inertia effects. While the dynamics in the bulk are characterized by a chaotic convective heat flow, the boundary layers at the horizontal container plates are essentially conducting and thus the fluid is motionless. Consequently, the average temperature exhibits a linear profile in the boundary layers. In this article, we rigorously investigate the average temperature and oscillations in the boundary layer via local bounds on the temperature field. Moreover, we deduce that the temperature profile is indeed essentially linear close to the horizontal container plates. Our results are uniform in the system parameters (e.g. the Rayleigh number) up to logarithmic correction terms. An important tool in our analysis is a new Hardy-type estimate for the convecting velocity field, which can be used to control the fluid motion in the layer. The bounds on the temperature field are derived with the help of local maximal regularity estimates for convection-diffusion equations.

  15. Internal gravity waves and hyperbolic boundary-value problems

    E-Print Network [OSTI]

    Some of the following aspects will be discussed: energy production and characteristic wave beams; radiation conditions; boundary integral equations.

  16. ANNIVERSARY REVIEW Grain boundary energy anisotropy: a review

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    energy (B) gained when the two surfaces are brought together and new bonds are formed. The grain boundaryANNIVERSARY REVIEW Grain boundary energy anisotropy: a review Gregory S. Rohrer Received: 29 April 2011 Abstract This paper reviews findings on the anisotropy of the grain boundary energies. After

  17. Mineralogical effects on the detectability of the postperovskite boundary

    E-Print Network [OSTI]

    Rhoads, James

    Mineralogical effects on the detectability of the postperovskite boundary Brent Grocholskia,1 discontinuity to the Pv - pPv boundary in pyrolite (homogenized mantle composition). Furthermore, the mineralogy have a detectable Pv - pPv boundary due to their distinct mineralogy. Therefore, the observation

  18. Numerical Study of Freestream Waves Receptivity and Nonlinear Breakdown in Hypersonic Boundary Layer

    E-Print Network [OSTI]

    Lei, Jia

    2013-01-01T23:59:59.000Z

    Numerical Methods for Hypersonic Boundary Layer Stability.of Instability in a Hypersonic Boundary Layer. TheoreticalA. P. , Receptivity of Hypersonic Boundary Layer to Wall

  19. Invariance properties of boundary sets of open embeddings of manifolds and their application to the abstract boundary

    E-Print Network [OSTI]

    Christopher J. Fama; Susan M. Scott

    1994-06-21T23:59:59.000Z

    The {\\em abstract boundary\\/} (or {\\em {\\em a\\/}-boundary\\/}) of Scott and Szekeres \\cite{Scott94} constitutes a ``boundary'' to any $n$-dimensional, paracompact, connected, Hausdorff, $C^\\infty$-manifold (without a boundary in the usual sense). In general relativity one deals with a {\\em space-% time\\/} $(\\cM,g)$ (a 4-dimensional manifold $\\cM$ with a Lorentzian metric $g$), together with a chosen preferred class of curves in $\\cM$. In this case the {\\em a\\/}-boundary points may represent ``singularities'' or ``points at infinity''. Since the {\\em a\\/}-boundary itself, however, does not depend on the existence of further structure on the manifold such as a Lorentzian metric or connection, it is possible for it to be used in many contexts. In this paper we develop some purely topological properties of abstract boundary sets and abstract boundary points ({\\em a\\/}-boundary points). We prove, amongst other things, that compactness is invariant under boundary set equivalence, and introduce another invariant concept ({\\em isolation\\/}), which encapsulates the notion that a boundary set is ``separated'' from other boundary points of the same embedding. ....... [The abstract continues in paper proper - truncated to fit here.

  20. Harmonic initial-boundary evolution in general relativity

    SciTech Connect (OSTI)

    Babiuc, Maria C. [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Szilagyi, Bela [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, 14476 Golm (Germany); Winicour, Jeffrey [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, 14476 Golm (Germany)

    2006-03-15T23:59:59.000Z

    Computational techniques which establish the stability of an evolution-boundary algorithm for a model wave equation with shift are incorporated into a well-posed version of the initial-boundary value problem for gravitational theory in harmonic coordinates. The resulting algorithm is implemented as a 3-dimensional numerical code which we demonstrate to provide stable, convergent Cauchy evolution in gauge wave and shifted gauge wave testbeds. Code performance is compared for Dirichlet, Neumann, and Sommerfeld boundary conditions and for boundary conditions which explicitly incorporate constraint preservation. The results are used to assess strategies for obtaining physically realistic boundary data by means of Cauchy-characteristic matching.

  1. Harmonic Initial-Boundary Evolution in General Relativity

    E-Print Network [OSTI]

    Maria C. Babiuc; Bela Szilagyi; Jeffrey Winicour

    2006-03-14T23:59:59.000Z

    Computational techniques which establish the stability of an evolution-boundary algorithm for a model wave equation with shift are incorporated into a well-posed version of the initial-boundary value problem for gravitational theory in harmonic coordinates. The resulting algorithm is implemented as a 3-dimensional numerical code which we demonstrate to provide stable, convergent Cauchy evolution in gauge wave and shifted gauge wave testbeds. Code performance is compared for Dirichlet, Neumann and Sommerfeld boundary conditions and for boundary conditions which explicitly incorporate constraint preservation. The results are used to assess strategies for obtaining physically realistic boundary data by means of Cauchy-characteristic matching.

  2. Four Dimensional Supersymmetric Theories in Presence of a Boundary

    E-Print Network [OSTI]

    Faizal, Mir

    2015-01-01T23:59:59.000Z

    In this paper, we study $\\mathcal{N} =1$ supersymmetric theories in four dimensions in presence of a boundary. We demonstrate that it is possible to preserve half the supersymmetry of the original theory by suitably modifying it in presence of a boundary. This is done by adding new boundary terms to the original action, such that the supersymmetric variation of the new terms exactly cancels the boundary terms generated by the supersymmetric transformation of the original bulk action. We also analyze the boundary projections of such supercharges used in such a theory. Finally, we study super-Yang-Mills theories in presence of a boundary using these results. We explicitly construct the action for the modified super-Yang-Mills theory, which preserves half the supersymmetry of the original theory, in presence of a boundary.

  3. Grain boundary characterization in an X750 alloy

    SciTech Connect (OSTI)

    Kevin Fisher; Sebastien Teysseyre; Emmanuelle Marquis

    2012-11-01T23:59:59.000Z

    Grain boundary chemistry in an X750 Ni alloy was analyzed by atom probe tomography in an effort to clarify the possible roles of elemental segregation and carbide presence on the stress corrosion cracking behavior of Ni alloys. Two types of cracks are observed: straight cracks along twin boundaries and wavy cracks at general boundaries. It was found that carbides (M23C6 and TiC) are present at both twin and general boundaries, with comparable B and P segregation for all types of grain boundaries. Twin boundaries intercept ?’ precipitates while the general boundaries wave around the ?’ and carbide precipitates. Near a crack tip, oxidation takes place on the periphery of carbide precipitate.

  4. Plasma waves reflection from a boundary with specular accommodative boundary conditions

    E-Print Network [OSTI]

    N. V. Gritsienko; A. V. Latyshev; A. A. Yushkanov

    2010-01-06T23:59:59.000Z

    In the present work the linearized problem of plasma wave reflection from a boundary of a half--space is solved analytically. Specular accommodative conditions of plasma wave reflection from plasma boundary are taken into consideration. Wave reflectance is found as function of the given parameters of the problem, and its dependence on the normal electron momentum accommodation coefficient is shown by the authors. The case of resonance when the frequency of self-consistent electric field oscillations is close to the proper (Langmuir) plasma oscillations frequency, namely, the case of long wave limit is analyzed. Refs. 17. Figs. 6.

  5. Boundary layer response to wind gusts

    E-Print Network [OSTI]

    Morland, Bruce Thomas

    1968-01-01T23:59:59.000Z

    of the wind tunnel sir stress caused by tbe addition of the in)actors, the decision was osde to use flew visuslstion ?echniques to detsreine if it wss possible to generate s lsuinar boundary layer on the flat plate. Loup black wss suspended in light..., 8. The data reduction procedure used in this thesis follcwed pxi- maxily the procsduxes of rafax'ence 8. Velocity fluctuations were detected using the constant current technique and computed based on square wave calibration. yor the constant...

  6. Microfluidics: The no-slip boundary condition

    E-Print Network [OSTI]

    Eric Lauga; Michael P. Brenner; Howard A. Stone

    2005-09-28T23:59:59.000Z

    The no-slip boundary condition at a solid-liquid interface is at the center of our understanding of fluid mechanics. However, this condition is an assumption that cannot be derived from first principles and could, in theory, be violated. We present a review of recent experimental, numerical and theoretical investigations on the subject. The physical picture that emerges is that of a complex behavior at a liquid/solid interface, involving an interplay of many physico-chemical parameters, including wetting, shear rate, pressure, surface charge, surface roughness, impurities and dissolved gas.

  7. ARM - Field Campaign - Boundary Layer Cloud IOP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3,Cloud OD Sensor TWST Cloud OD SensorgovCampaignsBoundary

  8. Supergravity at the boundary of AdS supergravity

    SciTech Connect (OSTI)

    Amsel, Aaron J.; Compere, Geoffrey [Department of Physics, University of California, Santa Barbara, California 93106 (United States)

    2009-04-15T23:59:59.000Z

    We give a general analysis of AdS boundary conditions for spin-3/2 Rarita-Schwinger fields and investigate boundary conditions preserving supersymmetry for a graviton multiplet in AdS{sub 4}. Linear Rarita-Schwinger fields in AdS{sub d} are shown to admit mixed Dirichlet-Neumann boundary conditions when their mass is in the range 0{<=}|m|<1/2l{sub AdS}. We also demonstrate that mixed boundary conditions are allowed for larger masses when the inner product is 'renormalized' accordingly with the action. We then use the results obtained for |m|=1/l{sub AdS} to explore supersymmetric boundary conditions for N=1 AdS{sub 4} supergravity in which the metric and Rarita-Schwinger fields are fluctuating at the boundary. We classify boundary conditions that preserve boundary supersymmetry or superconformal symmetry. Under the AdS/CFT dictionary, Neumann boundary conditions in d=4 supergravity correspond to gauging the superconformal group of the three-dimensional CFT describing M2-branes, while N=1 supersymmetric mixed boundary conditions couple the CFT to N=1 superconformal topologically massive gravity.

  9. A robust and accurate outflow boundary condition for ...

    E-Print Network [OSTI]

    S. Dong

    2014-01-15T23:59:59.000Z

    Jan 3, 2014 ... expressions (18a)–(18c) satisfy Eq. (3) on the outflow boundaries. ..... formation region marks the initial position of fully shed vortex and the ...

  10. atmosphere boundary layer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

  11. atmospheric boundary layer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

  12. atmospheric boundary layers: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

  13. Microsoft Word - 51-9105936-001 NHS boundaries and interfaces...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    System Included components Boundaries Physical interfaces Other interfaces the detector wells for the sensing device of the external neutron flux detectors 11) Component Handling...

  14. On the renormalization of the Gibbons-Hawking boundary term

    E-Print Network [OSTI]

    Ted Jacobson; Alejandro Satz

    2013-10-03T23:59:59.000Z

    The bulk (Einstein-Hilbert) and boundary (Gibbons-Hawking) terms in the gravitational action are generally renormalized differently when integrating out quantum fluctuations. The former is affected by nonminimal couplings, while the latter is affected by boundary conditions. We use the heat kernel method to analyze this behavior for a nonminimally coupled scalar field, the Maxwell field, and the graviton field. Allowing for Robin boundary conditions, we examine in which cases the renormalization preserves the ratio of boundary and bulk terms required for the effective action to possess a stationary point. The implications for field theory and black hole entropy computations are discussed.

  15. Existence of solutions to boundary value problems for smectic liquid ...

    E-Print Network [OSTI]

    2009-05-25T23:59:59.000Z

    Existence of solutions to boundary value problems for smectic liquid crys- tals. Abstract. We investigate variational problems for an energy developed by the.

  16. an inverse boundary value problem for the stationary transport ...

    E-Print Network [OSTI]

    outer normal to ?X at x ? ?X. Let us denote by f the solution (if exists) to the following boundary value problem for the stationary linear transport (Boltzmann)

  17. General Schema for [001] Tilt Grain Boundaries in Dense Packing...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    as showing the frustration of symmetry caused by the incorporation of point defects (vacancies and impurities). This general model for grain boundary structures can, in principle,...

  18. arctic boundary layer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of many theoretical studies over the last forty years. (A Davies, Christopher 18 Tropical cyclone boundary layer shocks CERN Preprints Summary: This paper presents numerical...

  19. absorbing boundary condition: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Summary: Absorbing Boundary Condition, Domain Decomposition and Hydrodynamic Wave Model O. Wilk Introduction. appli. (wave equation) Num. appli. (hydro. wave model)...

  20. absorbing boundary conditions: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Summary: Absorbing Boundary Condition, Domain Decomposition and Hydrodynamic Wave Model O. Wilk Introduction. appli. (wave equation) Num. appli. (hydro. wave model)...

  1. Ks-band detection of thermal emission and color constraints to CoRoT-1b: A low-albedo planet with inefficient atmospheric energy redistribution and a temperature inversion

    E-Print Network [OSTI]

    Rogers, Justin C; Lopez-Morales, Mercedes; Sing, David K; Burrows, Adam

    2009-01-01T23:59:59.000Z

    We report the detection in Ks-band of the secondary eclipse of the hot Jupiter CoRoT-1b, from time series photometry with the ARC 3.5-m telescope at Apache Point Observatory. The eclipse shows a depth of 0.336+/-0.042 percent and is centered at phase 0.5022 (+0.0023,-0.0027), consistent with a zero eccentricity orbit ecos{\\omega} = 0.0035 (+0.0036,-0.0042). We perform the first optical to near-infrared multi-band photometric analysis of an exoplanet's atmosphere and constrain the reflected and thermal emissions by combining our result with the recent 0.6, 0.71, and 2.09 micron secondary eclipse detections by Snellen et al. (2009), Gillon et al. (2009), and Alonso et al. (2009a). Comparing the multi-wavelength detections to state-of-the-art radiative-convective chemical-equilibrium atmosphere models, we find the near-infrared fluxes difficult to reproduce. The closest blackbody-based and physical models provide the following atmosphere parameters: a temperature T = 2454 (+84,-170) K, a very low Bond albedo A_B...

  2. Turbulence Structure and Wall Signature in Hypersonic Turbulent Boundary Layer

    E-Print Network [OSTI]

    Martín, Pino

    Turbulence Structure and Wall Signature in Hypersonic Turbulent Boundary Layer Yin-Chiu Kan , Clara and hypersonic turbulent boundary layer datasets from direct numerical simulation (DNS). Contour plots and Marusic5 and Mathis, Hutchins and Marusic16 ). In contrast to supersonic and hypersonic flow regimes

  3. Analytic Functions in Smirnov Classes Ep Real Boundary Values

    E-Print Network [OSTI]

    Khavinson, Dmitry

    Analytic Functions in Smirnov Classes Ep with Real Boundary Values L. De Castro and D. Khavinson. [1] Ch. 10.) Definition 1. An analytic function f(z) in G is said to belong to the class Ep (G) for p known that for p 1 functions in Ep -classes can be represented as Cauchy integrals of their boundary

  4. MOLECULAR DYNAMICS SIMULATION OF THERMAL BOUNDARY CONDUCTANCE BETWEEN SWNT AND

    E-Print Network [OSTI]

    Maruyama, Shigeo

    MOLECULAR DYNAMICS SIMULATION OF THERMAL BOUNDARY CONDUCTANCE BETWEEN SWNT AND SURROUNDING FLUIDS JinHyeok Cha, Shohei Chiashi, Junichiro Shiomi, and Shigeo Maruyama* Department of Mechanical applications. In particular, the thermal boundary conductance (TBC) K between an SWNT and surrounding fluid

  5. Distribution of Grain Boundary Planes and Misorientations in Magnesium Oxide

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    Distribution of Grain Boundary Planes and Misorientations in Magnesium Oxide D.M. Saylor 1 , A distribution, magnesium oxide. Abstract. We have developed a technique that allows the geometry of polycrystalline magnesium oxide. Using these data, we have specified the distribution of grain boundaries within

  6. Model of Trace Gas Flux in Boundary Layer

    E-Print Network [OSTI]

    I. I. Vasenev; I. S. Nurgaliev

    2013-03-04T23:59:59.000Z

    Mathematical model of the turbulent flux in the three-layer boundary system is presented. Turbulence is described as a presence of the nonzero vorticity. Generalized advection-diffusion-reaction equation is derived for arbitrary number components in the flux. The fluxes in the layers are objects for matching requirements on the boundaries between the layers.

  7. Irradiation Assisted Grain Boundary Segregation in Steels

    SciTech Connect (OSTI)

    Lu, Zheng; Faulkner, Roy G. [IPTME, Loughborough University, Loughborough, Leics (United Kingdom)

    2008-07-01T23:59:59.000Z

    The understanding of radiation-induced grain boundary segregation (RIS) has considerably improved over the past decade. New models have been introduced and much effort has been devoted to obtaining comprehensive information on segregation from the literature. Analytical techniques have also improved so that chemical analysis of layers 1 nm thick is almost routine. This invited paper will review the major methods used currently for RIS prediction: namely, Rate Theory, Inverse Kirkendall, and Solute Drag approaches. A summary is made of the available data on phosphorus RIS in reactor pressure vessel (RPV) steels. This will be discussed in the light of the predictions of the various models in an effort to show which models are the most reliable and easy to use for forecasting P segregation behaviour in steels. A consequence of RIS in RPV steels is a radiation induced shift in the ductile to brittle transition temperature (DBTT). It will be shown how it is possible to relate radiation-induced P segregation levels to DBTT shift. Examples of this exercise will be given for RPV steels and for ferritic steels being considered for first wall fusion applications. Cr RIS in high alloy stainless steels and associated irradiation-assisted stress corrosion cracking (IASCC) will be briefly discussed. (authors)

  8. Compressional boundaries in the Earth's foreshock

    SciTech Connect (OSTI)

    Rojas-Castillo, D.; Blanco-Cano, X. [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Coyoacan (Mexico); Kajdic, P. [Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Omidi, N. [Solana Scientific Inc., Solana Beach, California (United States)

    2013-06-13T23:59:59.000Z

    The terrestrial foreshock is a highly dynamic region populated by particles, waves and non-linear structures such as shocklets, SLAMS, hot flow anomalies, cavities and cavitons. Recently a new structure named foreshock compressional boundary (FCB) was reported in global hybrid simulations by Omidi et al. (2009). This structure represents a transition region that separates the highly disturbed foreshock plasma from pristine solar wind or from the region of field-aligned ion beams. The FCB is associated with a strong compression of magnetic field and density. Besides the enhancements in the field and density, the FCB also shows a region where these two quantities decrease below the ambient solar wind (SW) values. Here, we study a FCB observed by Cluster-1. This FCB shows that although sometimes FCBs are transition regions between the pristine solar wind plasma and the foreshock plasma, in this case the FCB separates a region with large amplitude waves from regions with high frequency (f{approx}1.7 Hz) small amplitude waves. We analyze the FCB properties, ion distributions inside them, and the waves near the structure.

  9. The Relationship Between Grain Boundary Energy, Grain Boundary Complexion Transitions, and Grain Size in Ca-doped Yttria

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    The Relationship Between Grain Boundary Energy, Grain Boundary Complexion Transitions, and Grain complexions. One idea is that complexion transitions occur to lower the average energy of the interface energy. Experiments on doped aluminas have shown that a complexion transition can change the relative

  10. Amplitude Analysis and Measurement of the Time-dependent CP Asymmetry of B0 to KsKsKs Decays

    SciTech Connect (OSTI)

    Lees, J.P.

    2012-04-11T23:59:59.000Z

    We present the first results on the Dalitz-plot structure and improved measurements of the time-dependent CP-violation parameters of the process B{sup 0} {yields} K{sub S}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0} obtained using 468 x 10{sup 6} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. The Dalitz-plot structure is probed by a time-integrated amplitude analysis that does not distinguish between B{sup 0} and {bar B}{sup 0} decays. We measure the total inclusive branching fraction {Beta}(B{sup 0} {yields} K{sub S}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}) = (6.19 {+-} 0.48 {+-} 0.15 {+-} 0.12) x 10{sup -6}, where the first uncertainty is statistical, the second is systematic, and the third represents the Dalitz-plot signal model dependence. We also observe evidence for the intermediate resonant states f{sub 0}(980), f{sub 0}(1710), and f{sub 2}(2010). Their respective product branching fractions are measured to be (2.70{sub -1.19}{sup +1.25} {+-} 0.36 {+-} 1.17) x 10{sup -6}, (0.50{sub -0.24}{sup +0.46} {+-} 0.04 {+-} 0.10) x 10{sup -6}, and (0.54{sub -0.20}{sup +0.21} {+-} 0.03 {+-} 0.52) x 10{sup -6}. Additionally, we determine the mixing-induced CP-violation parameters to be S = -0.94{sub -0.21}{sup +0.24} {+-} 0.06 and C = -0.17 {+-} 0.18 {+-} 0.04, where the first uncertainty is statistical and the second is systematic. These values are in agreement with the standard model expectation.

  11. Kapitza Resistance of the Grain Boundaries in Ceria

    SciTech Connect (OSTI)

    David Bai; Jian Gan; Aleksandr Chernatynskiy

    2014-06-01T23:59:59.000Z

    Thermal conductivity is one of the key performance metrics of the nuclear fuels. In electrical insulators, such as most ubiquitous nuclear fuel – UO2, thermal transport is due to phonons, or lattice waves. Their propagation is impeded by any lattice defect, such as impurities or vacancies, as well as larger microstructural features: grain boundaries, dislocations and pores/bubbles. Detailed description of the phonons interactions with these features is still lacking. In this work, we elucidate the dependence of the grain boundary thermal resistance, also known as a Kapitza resistance, on the type and misorientation angle of the grain boundary in model system of CeO2.

  12. A Cartesian embedded boundary method for hyperbolic conservation laws

    SciTech Connect (OSTI)

    Sjogreen, B; Petersson, N A

    2006-12-04T23:59:59.000Z

    The authors develop an embedded boundary finite difference technique for solving the compressible two- or three-dimensional Euler equations in complex geometries on a Cartesian grid. The method is second order accurate with an explicit time step determined by the grid size away from the boundary. Slope limiters are used on the embedded boundary to avoid non-physical oscillations near shock waves. They show computed examples of supersonic flow past a cylinder and compare with results computed on a body fitted grid. Furthermore, they discuss the implementation of the method for thin geometries, and show computed examples of transonic flow past an airfoil.

  13. Category:Goodland, KS | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarreis aCallahanWind FarmAdd a new FederalGeothermal Media in

  14. Microsoft Word - Gage-KS.doc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMappingENVIRONMENTALHYDROPOWER MEETINGR&D Program3S

  15. Grain-boundary engineering markedly reduces susceptibility to intergranular hydrogen embrittlement in metallic materials

    E-Print Network [OSTI]

    Ritchie, Robert

    Grain-boundary engineering markedly reduces susceptibility to intergranular hydrogen embrittlement. Keywords: Hydrogen embrittlement; Intergranular cracking; Grain-boundary engineering; Special boundaries,e,* a Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA b

  16. Boundary Circles of Mixed Phase Space, Hamiltonian Systems

    E-Print Network [OSTI]

    Or Alus; Shmuel Fishman; James D. Meiss

    2014-10-28T23:59:59.000Z

    The phase space of an area-preserving map typically contains infinitely many elliptic islands embedded in a chaotic sea. Orbits near the boundary of a chaotic region have been observed to stick for long times, strongly influencing their transport properties. The boundary is composed of invariant circles, called "Boundary circles." We investigate the distribution of rotation numbers of boundary circles for the Henon quadratic map and show that the probability of occurrence of small elements of their continued fraction expansions is larger than would be expected for a number chosen at random. However, large elements occur with probabilities distributed proportionally to the random case. These results have implications for models of transport in mixed phase space.

  17. Mineral Deformation at Earth's Core-Mantle Boundary

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Deformation at Earth's Core-Mantle Boundary Print Wednesday, 31 August 2011 00:00 Earth is a dynamic planet in which convection takes place on the scale of thousands of...

  18. An uncertainty principle, Wegner estimates and localization near fluctuation boundaries

    E-Print Network [OSTI]

    Anne Boutet de Monvel; Daniel Lenz; Peter Stollmann

    2009-05-18T23:59:59.000Z

    We prove a simple uncertainty principle and show that it can be applied to prove Wegner estimates near fluctuation boundaries. This gives new classes of models for which localization at low energies can be proven.

  19. Grain Boundary (GB) Studies in Nano- and Micro- Crystalline Materials

    E-Print Network [OSTI]

    Tanju, Mst Sohanazaman

    2011-01-01T23:59:59.000Z

    boundaries in silicon? Materials research society, Vol.122,bicrystal? Journal of Materials Science, 40(2005)3137- 5.in ZnO? Journal of Materials Science, 40(2005)3067-3074. 6.

  20. Reconfiguring Boundary Relations: Robotic Innovations in Pharmacy Work

    E-Print Network [OSTI]

    Barrett, Michael

    Robotics is a rapidly expanding area of digital innovation with important implications for organizational practice in multioccupational settings. This paper explores the influence of robotic innovations on the boundary ...

  1. Science at the interface : grain boundaries in nanocrystalline metals.

    SciTech Connect (OSTI)

    Rodriguez, Mark Andrew; Follstaedt, David Martin; Knapp, James Arthur; Brewer, Luke N.; Holm, Elizabeth Ann; Foiles, Stephen Martin; Hattar, Khalid M.; Clark, Blythe B.; Olmsted, David L.; Medlin, Douglas L.

    2009-09-01T23:59:59.000Z

    Interfaces are a critical determinant of the full range of materials properties, especially at the nanoscale. Computational and experimental methods developed a comprehensive understanding of nanograin evolution based on a fundamental understanding of internal interfaces in nanocrystalline nickel. It has recently been shown that nanocrystals with a bi-modal grain-size distribution possess a unique combination of high-strength, ductility and wear-resistance. We performed a combined experimental and theoretical investigation of the structure and motion of internal interfaces in nanograined metal and the resulting grain evolution. The properties of grain boundaries are computed for an unprecedented range of boundaries. The presence of roughening transitions in grain boundaries is explored and related to dramatic changes in boundary mobility. Experimental observations show that abnormal grain growth in nanograined materials is unlike conventional scale material in both the level of defects and the formation of unfavored phases. Molecular dynamics simulations address the origins of some of these phenomena.

  2. advancing subduction boundary: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    widens the thermally-defined seismogenic zone by shifting the intersection of the 350 C isotherm within the plate boundary fault 30 55 km landward. In contrast to the Nankai...

  3. Eddy-mean flow interactions in western boundary current jets

    E-Print Network [OSTI]

    Waterman, Stephanie N

    2009-01-01T23:59:59.000Z

    This thesis examines the nature of eddy-mean flow interactions in western boundary current jets and recirculation gyre dynamics from both theoretical and observational perspectives. It includes theoretical studies of ...

  4. Grain Boundary Structure Effects on Intergranular Stress Corrosion Cracking of

    E-Print Network [OSTI]

    Olson, Tamara

    Grain Boundary Structure Effects on Intergranular Stress Corrosion Cracking of Alloy X­750 Y. Pan B­of­freedom) and correlations with intergranular stress corrosion cracking observed in Alloy X­750. Orientation imaging

  5. Current transport along grain boundaries in d-wave superconductors.

    SciTech Connect (OSTI)

    Carmody, M.; Marks, L. D.; Merkle, K. L.; Materials Science Division; Northwestern Univ.

    2002-05-01T23:59:59.000Z

    The use of a classic phase retrieval algorithm has been previously used to determine the local critical current J{sub c}(x) along the length of grain boundary Josephson junctions that can be characterized using a standard s-wave model. The phase retrieval approach has been modified for use with d-wave dominated superconductors to allow for negative local currents along the boundary. In general solutions to the 1-D phase problem are not unique, however in the present work special constraints are employed experimentally to ensure uniqueness. The various current distribution solutions and their possible uniqueness are explored. The solutions are consistent with most existing d-wave Josephson junction boundary models and can be used to understand the basic current distribution along 45 degree YaBa{sub 2}Cu{sub 3}O{sub 7-x} grain boundary junctions as well as providing a means for mapping the location of self-generated flux cores.

  6. Compressed absorbing boundary conditions for the Helmholtz equation

    E-Print Network [OSTI]

    Bélanger-Rioux, Rosalie

    2014-01-01T23:59:59.000Z

    Absorbing layers are sometimes required to be impractically thick in order to offer an accurate approximation of an absorbing boundary condition for the Helmholtz equation in a heterogeneous medium. It is always possible ...

  7. Symmetry in exterior boundary value problems for quasilinear ...

    E-Print Network [OSTI]

    symmetry for the solution u and for the condenser ?i when the overdetermined boundary condition |Du| = c > 0 on d?i is imposed. This provides a new proof of a

  8. A multilevel preconditioner for domain decomposition boundary systems

    SciTech Connect (OSTI)

    Bramble, J.H.; Pasciak, J.E.; Xu, Jinchao.

    1991-12-11T23:59:59.000Z

    In this note, we consider multilevel preconditioning of the reduced boundary systems which arise in non-overlapping domain decomposition methods. It will be shown that the resulting preconditioned systems have condition numbers which be bounded in the case of multilevel spaces on the whole domain and grow at most proportional to the number of levels in the case of multilevel boundary spaces without multilevel extensions into the interior.

  9. VANISHING VISCOSITY SOLUTIONS OF HYPERBOLIC SYSTEMS WITH BOUNDARY CONDITIONS

    E-Print Network [OSTI]

    Bianchini, Stefano

    and travelling profiles 18 4.2. Explicit form for the source terms 25 4.3. Initial­boundary data decomposition 28. Interaction functionals 36 6.1. Interactions of waves of di#erent families 37 6.2. Interactions of waves analisys is the parabolic system with boundary E:parasys1 (1.1) u t +A(u)u x = u xx in t # R + , x # (x b

  10. The boundary F-theorem for free fields

    E-Print Network [OSTI]

    J. S. Dowker

    2014-07-23T23:59:59.000Z

    The boundary free energy, as defined by Gaiotto, is further analysed for free scalars on a hemisphere and shown to be the same as the N-D determinant that earlier occurred in a treatment of GJMS operators. It is also shown to be identical, up to spin degeneracy, to the free energy for a spin-half field on the hemisphere boundary. This is also true if the hemisphere is replaced by a lune. The calculations are carried out in arbitrary dimensions.

  11. Distributed boundary layer suction utilizing wing tip effects

    E-Print Network [OSTI]

    Edwards, Jay Thomas

    2012-06-07T23:59:59.000Z

    that this is not the case. The rotational force at the tip accounts for the suction power. Since this power is utilized to suck air from the boundary, energy is dissipated, thereby weakening the vortex strength. Providing this assumption is valid, the effect would... was done. TABLE OF CONTENTS Chapter Page INTRODUCTION OBJECTIVES AND SCOPE EXPERIMENTAL FACILITY AND PROCEDURES Wing Model . Wake Rake Boundary Layer Probe . . Multiple Tube Manometers Wind Tunnel and Related Equipment Procedures Computation...

  12. Biofuel Boundaries: Estimating the Medium-Term Supply Potential of Domestic Biofuels

    E-Print Network [OSTI]

    Jones, Andrew; O'Hare, Michael; Farrell, Alexander

    2007-01-01T23:59:59.000Z

    Biofuel Boundaries: Estimating the Medium-Term SupplyAugust 22, 2007 Biofuel Boundaries: Estimating the Medium-significant amount of liquid biofuel (equivalent to 30-100%

  13. E-Print Network 3.0 - artificial boundary conditions Sample Search...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    obtained from satellite (above) and GPS mea- surements 1 as boundary conditions. The ice... by Glen's flow law: Boundary conditions are ... Source: Langhorne, Pat - Department...

  14. Structural Dependence of Grain Boundary Resistance in Copper Nanowires

    SciTech Connect (OSTI)

    Kim, Tae Hwan [ORNL; Zhang, Xiaoguang [ORNL; Nicholson, Don M [ORNL; Radhakrishnan, Bala [ORNL; Radhakrishnan, Balasubramaniam [ORNL; Evans III, Boyd Mccutchen [ORNL; Kulkarni, Nagraj S [ORNL; Kenik, Edward A [ORNL; Meyer III, Harry M [ORNL; Li, An-Ping [ORNL

    2011-01-01T23:59:59.000Z

    The current choice of the interconnect metal in integrated circuits is copper due to its higher electrical conductivity and improved electromigration reliability in comparison with aluminum. However, with reducing feature sizes, the resistance of copper interconnects (lines) increases dramatically. Greater resistance will result in higher energy use, more heat generation, more failure due to electromigration, and slower switching speeds. To keep pace with the projected planar transistor density, the first challenge is to identify the dominant factors that contribute to the high interconnect resistance. Here we directly measure individual grain boundary (GB) resistances in copper nanowires with a one-to-one correspondence to the GB structure. The specific resistivities of particular GBs are measured using four-probe scanning tunneling microscopy (STM) to establish a direct link between GB structure and the resistance. High-angle random GBs contribute to a specific resistivity of about 25 10-12 cm2 for each boundary, while coincidence boundaries are significantly less-resistive than random boundaries. Thus, replacing random boundaries with coincidence ones would be a route to suppress the GB impact to the resistivity of polycrystalline conductors. Acknowledgement: The research was supported by the Division of Scientific User Facilities, U. S. Department of Energy.

  15. Superconducting circuit boundary conditions beyond the Dynamical Casimir Effect

    E-Print Network [OSTI]

    Jason Doukas; Jorma Louko

    2015-02-18T23:59:59.000Z

    We study analytically the time-dependent boundary conditions of superconducting microwave circuit experiments in the high plasma frequency limit, in which the conditions are Robin-type and relate the value of the field to the spatial derivative of the field. We give an explicit solution to the field evolution for boundary condition modulations that are small in magnitude but may have arbitrary time dependence, in a formalism that applies both to a semiopen waveguide and to a closed waveguide with two independently adjustable boundaries. The correspondence between the microwave Robin boundary conditions and the mechanically-moving Dirichlet boundary conditions of the Dynamical Casimir Effect is shown to break down at high field frequencies, approximately one order of magnitude above the frequencies probed in the 2011 experiment of Wilson et al. Our results bound the parameter regime in which a microwave circuit can be used to model relativistic effects in a mechanically-moving cavity, and they show that beyond this parameter regime moving mirrors produce more particles and generate more entanglement than their non-moving microwave waveguide simulations.

  16. Surface heterogeneity impacts on boundary layer dynamics via energy balance partitioning

    E-Print Network [OSTI]

    Brunsell, Nathaniel A.; Mechem, David B.; Anderson, M. C.

    2011-04-11T23:59:59.000Z

    energy balance partitioning N. A. Brunsell1, D. B. Mechem1, and M. C. Anderson2 1Dept. of Geography, University of Kansas, Lawrence, KS, USA 2Hydrology and Remote Sensing Laboratory, USDA. Beltsville, MD, USA Received: 22 June 2010 – Published in Atmos... responsible for altering surface heat and moisture fluxes. Twelve coupled land surface – large eddy simulation scenarios with four different length scales of surface variability under three different horizontal wind speeds are used in the analysis. The base...

  17. Wind on the boundary for the Abelian sandpile model

    E-Print Network [OSTI]

    Philippe Ruelle

    2007-07-25T23:59:59.000Z

    We continue our investigation of the two-dimensional Abelian sandpile model in terms of a logarithmic conformal field theory with central charge c=-2, by introducing two new boundary conditions. These have two unusual features: they carry an intrinsic orientation, and, more strangely, they cannot be imposed uniformly on a whole boundary (like the edge of a cylinder). They lead to seven new boundary condition changing fields, some of them being in highest weight representations (weights -1/8, 0 and 3/8), some others belonging to indecomposable representations with rank 2 Jordan cells (lowest weights 0 and 1). Their fusion algebra appears to be in full agreement with the fusion rules conjectured by Gaberdiel and Kausch.

  18. Schrödinger functional boundary conditions and improvement for N>3

    E-Print Network [OSTI]

    Ari Hietanen; Tuomas Karavirta; Pol Vilaseca

    2014-08-29T23:59:59.000Z

    The standard method to calculate non-perturbatively the evolution of the running coupling of a SU(N) gauge theory is based on the Schr\\"odinger functional (SF). In this paper we construct a family of boundary fields for general values of N which enter the standard definition of the SF coupling. We provide spatial boundary conditions for fermions in several representations which reduce the condition number of the squared Dirac operator. In addition, we calculate the O(a) improvement coefficients for N>3 needed to remove boundary cutoff effects from the gauge action. After this, residual cutoff effects on the step scaling function are shown to be very small even when considering non-fundamental representations. We also calculate the ratio of Lambda parameters between the MS-bar and SF schemes.

  19. Contaminant Boundary at the Faultless Underground Nuclear Test

    SciTech Connect (OSTI)

    Greg Pohll; Karl Pohlmann; Jeff Daniels; Ahmed Hassan; Jenny Chapman

    2003-04-01T23:59:59.000Z

    The U.S. Department of Energy (DOE) and the Nevada Division of Environmental Protection (NDEP) have reached agreement on a corrective action strategy applicable to address the extent and potential impact of radionuclide contamination of groundwater at underground nuclear test locations. This strategy is described in detail in the Federal Facility Agreement and Consent Order (FFACO, 2000). As part of the corrective action strategy, the nuclear detonations that occurred underground were identified as geographically distinct corrective action units (CAUs). The strategic objective for each CAU is to estimate over a 1,000-yr time period, with uncertainty quantified, the three-dimensional extent of groundwater contamination that would be considered unsafe for domestic and municipal use. Two types of boundaries (contaminant and compliance) are discussed in the FFACO that will map the three-dimensional extent of radionuclide contamination. The contaminant boundary will identify the region wi th 95 percent certainty that contaminants do not exist above a threshold value. It will be prepared by the DOE and presented to NDEP. The compliance boundary will be produced as a result of negotiation between the DOE and NDEP, and can be coincident with, or differ from, the contaminant boundary. Two different thresholds are considered for the contaminant boundary. One is based on the enforceable National Primary Drinking Water Regulations for radionuclides, which were developed as a requirement of the Safe Drinking Water Act. The other is a risk-based threshold considering applicable lifetime excess cancer-risk-based criteria The contaminant boundary for the Faultless underground nuclear test at the Central Nevada Test Area (CNTA) is calculated using a newly developed groundwater flow and radionuclide transport model that incorporates aspects of both the original three-dimensional model (Pohlmann et al., 1999) and the two-dimensional model developed for the Faultless data decision analysis (DDA) (Pohll and Mihevc, 2000). This new model includes the uncertainty in the three-dimensional spatial distribution of lithology and hydraulic conductivity from the 1999 model as well as the uncertainty in the other flow and transport parameters from the 2000 DDA model. Additionally, the new model focuses on a much smaller region than was included in the earlier models, that is, the subsurface within the UC-1 land withdrawal area where the 1999 model predicted radionuclide transport will occur over the next 1,000 years. The purpose of this unclassified document is to present the modifications to the CNTA groundwater flow and transport model, to present the methodology used to calculate contaminant boundaries, and to present the Safe Drinking Water Act and risk-derived contaminant boundaries for the Faultless underground nuclear test CAU.

  20. Turbulence Structure and Wall Signature in Hypersonic Boundary Layer

    E-Print Network [OSTI]

    Martín, Pino

    Turbulence Structure and Wall Signature in Hypersonic Boundary Layer Yin-Chiu Kan , Beekman Izaak and low- speed features, found in subsonic experiments, are present in our supersonic and hypersonic and hypersonic regimes due to the lack of detailed flow field data, and the studies have been mostly restricted

  1. Meta-Design: Expanding Boundaries and Redistributing Control in Design

    E-Print Network [OSTI]

    Fischer, Gerhard

    Meta-Design: Expanding Boundaries and Redistributing Control in Design Gerhard Fischer Center for Lifelong Learning and Design University of Colorado, Boulder http://l3d.cs.colorado.edu/~gerhard/ Abstract. Meta-design is an emerging conceptual framework aimed at defining and creating socio

  2. OFFSHORE BOUNDARY-LAYER MODELLING H. Bergstrm1

    E-Print Network [OSTI]

    OFFSHORE BOUNDARY-LAYER MODELLING H. Bergström1 and R. Barthelmie2 1) Uppsala Univ., Dept. of Earth) of the ENDOW (EfficieNt Development of Offshore Windfarms) project, where the objectives are to provide currently be incorporated into a wind farm design tool. The offshore thermal stratification climate is also

  3. Supersymmetric vertex models with domain wall boundary conditions

    SciTech Connect (OSTI)

    Zhao Shaoyou; Zhang Yaozhong [Department of Mathematics, University of Queensland, Brisbane, QLD 4072 (Australia); Department of Mathematics, University of Queensland, Brisbane, QLD 4072 (Australia) and Physikalisches Institut, Universitaet Bonn, D-53115 Bonn (Germany)

    2007-02-15T23:59:59.000Z

    By means of the Drinfeld twists, we derive the determinant representations of the partition functions for the gl(1 vertical bar 1) and gl(2 vertical bar 1) supersymmetric vertex models with domain wall boundary conditions. In the homogeneous limit, these determinants degenerate to simple functions.

  4. On Boundary Control Problems in Slow Processes for Piezothermoelastic Plates

    E-Print Network [OSTI]

    Adriano Montanaro

    2008-08-07T23:59:59.000Z

    We consider a piezothermoelastic panel occupied by a material of hexagonal crystal class. We study the response when the boundary conditions vary very slowly with time and one of the bounding faces is subject to thermal exposure. We show that in some cases the temperature on the other bounding face can be controlled by the difference of electric potential between the faces.

  5. Modeling boundary measurements of scattered light using the corrected

    E-Print Network [OSTI]

    Kim, Arnold D.

    to numerical solutions of the radiative transport equation. © 2012 Optical Society of America OCIS codes: (170Adams and B. J. Tromberg, "Boundary conditions for the diffusion equation in radiative transfer," J. Opt. Soc element method to solve the diffusion equation. We show that this corrected diffusion approximation models

  6. Computational quantum-classical boundary of commuting quantum circuits

    E-Print Network [OSTI]

    Keisuke Fujii; Shuhei Tamate

    2014-06-26T23:59:59.000Z

    It is often said that the transition from quantum to classical worlds is caused by decoherence originated from an interaction between a system of interest and its surrounding environment. Here we establish a computational quantum-classical boundary from the viewpoint of classical simulatability of a quantum system under decoherence. Specifically, we consider the commuting quantum circuits as dynamics of the quantum system. To show intractability of classical simulation above the boundary, we utilize the postselection argument introduced by M. J. Bremner, R. Jozsa, and D. J. Shepherd [Proceedings of the Royal Society A: Mathematical, Physical and Engineering Science 465, 1413 (2009).] and crucially strengthen its statement by taking noise effect into account. Classical simulatability below the boundary is shown by taking a projected-entangled-pair-state picture. Not only the separability criteria but also the condition for the entangled pair to become a convex mixture of stabilizer states is developed to show classical simulatability of highly entangling operations. We found that when each qubit is subject to a single-qubit complete-positive-trace-preserving noise, the computational quantum-classical boundary is tightly given by the dephasing rate required for the magic state distillation.

  7. Topological order in Josephson junction ladders with Mobius boundary conditions

    E-Print Network [OSTI]

    G. Cristofano; V. Marotta; A. Naddeo

    2005-03-22T23:59:59.000Z

    We propose a CFT description for a closed one-dimensional fully frustrated ladder of quantum Josephson junctions with Mobius boundary conditions, in particular we show how such a system can develop topological order. Such a property is crucial for its implementation as a "protected" solid state qubit.

  8. HIGHER REGULARITY OF THE FREE BOUNDARY IN THE ...

    E-Print Network [OSTI]

    2014-06-19T23:59:59.000Z

    cise asymptotic behavior of the solutions near regular free boundary points. The second and main ...... Next, we compute the Weiss energy functional. W0(r, u) = 1 ..... Theorem 3.4. There exists a small constant ? = ?u > 0, such that T is a home-.

  9. Boundary quantum Knizhnik-Zamolodchikov equations and Bethe vectors

    E-Print Network [OSTI]

    Nicolai Reshetikhin; Jasper Stokman; Bart Vlaar

    2014-07-18T23:59:59.000Z

    Solutions to boundary quantum Knizhnik-Zamolodchikov equations are constructed as bilateral sums involving "off-shell" Bethe vectors in case the reflection matrix is diagonal and only the 2-dimensional representation of $U_q(\\hat{\\frak{sl}(2)})$ is involved. We also consider their rational and classical degenerations.

  10. ON EXISTENCE AND UNIQUENESS IN A FREE BOUNDARY ...

    E-Print Network [OSTI]

    2002-10-24T23:59:59.000Z

    consists of finding a nonnegative continuous function u in QT = Rn ×(0,T), ...... (t0 ? ?, t0 + ?) because of everywhere density of R and continuity of |?w?(x; t)| in ... the solution u is of parabolic Hölder class H2+?(?? QT ) (see G. Lieberman's book .... In Free boundary problems, theory and applications (Zakopane, 1995); ...

  11. Contributed Paper Protected-Area Boundaries as Filters of

    E-Print Network [OSTI]

    Kratochvíl, Lukas

    Contributed Paper Protected-Area Boundaries as Filters of Plant Invasions LLEWELLYN C. FOXCROFT of Pretoria, Pretoria 0002, South Africa Abstract: Human land uses surrounding protected areas provide propagules for colonization of these areas by non-native species, and corridors between protected-area

  12. Prediction-Based Compression Ratio Boundaries for Medical Images

    E-Print Network [OSTI]

    Qi, Xiaojun

    Prediction-Based Compression Ratio Boundaries for Medical Images Xiaojun Qi Computer Science present prediction-based image compression techniques take advantage of either intra- or inter function. The prediction-based compression technique has been applied on some magnetic resonance (MR) brain

  13. Non-dissipative boundary feedback for Rayleigh and Timoshenko beams

    E-Print Network [OSTI]

    Opmeer, Mark

    Non-dissipative boundary feedback for Rayleigh and Timoshenko beams Chris Guiver and Mark R. Opmeer-dissipative feedback that has been shown in the literature to exponentially stabilize an Euler-Bernoulli beam makes a Rayleigh beam and a Timoshenko beam unstable. 1 Introduction Feedback control of beams is a much studied

  14. Fractal boundary basins in spherically symmetric $?^4$ theory

    E-Print Network [OSTI]

    Ethan P. Honda

    2011-06-14T23:59:59.000Z

    Results are presented from numerical simulations of the flat-space nonlinear Klein-Gordon equa- tion with an asymmetric double-well potential in spherical symmetry. Exit criteria are defined for the simulations that are used to help understand the boundaries of the basins of attraction for Gaussian "bubble" initial data. The first exit criteria, based on the immediate collapse or expan- sion of bubble radius, is used to observe the departure of the scalar field from a static intermediate attractor solution. The boundary separating these two behaviors in parameter space is smooth and demonstrates a time-scaling law with an exponent that depends on the asymmetry of the potential. The second exit criteria differentiates between the creation of an expanding true-vacuum bubble and dispersion of the field leaving the false vacuum; the boundary separating these basins of attraction is shown to demonstrate fractal behavior. The basins are defined by the number of bounces that the field undergoes before inducing a phase transition. A third, hybrid exit criteria is used to determine the location of the boundary to arbitrary precision and to characterize the threshold behavior. The possible effects this behavior might have on cosmological phase transitions are briefly discussed.

  15. Trans Boundary Transport of Pollutants by Atmospheric Mineral

    E-Print Network [OSTI]

    Einat, Aharonov

    Trans Boundary Transport of Pollutants by Atmospheric Mineral Dust Y I G A L E R E L , * , U R I D, and solid constituents in the atmosphere (3-11). Uptake of pollutants by mineral dust has been shown Jerusalem, Israel The transport of anthropogenic pollution by desert dust in the Eastern Mediterranean

  16. NANO REVIEW Open Access Thermal conductivity and thermal boundary

    E-Print Network [OSTI]

    Boyer, Edmond

    NANO REVIEW Open Access Thermal conductivity and thermal boundary resistance of nanostructures and the thermal transport prop- erties is a key point to design materials with preferred thermal properties with the heat dissipation on them. The influence of the interfacial roughness on the thermal conductivity

  17. Pushing the boundaries of the thermal conductivity of materials

    E-Print Network [OSTI]

    Braun, Paul

    Pushing the boundaries of the thermal conductivity of materials David G. Cahill, C. Chiritescu, Y. · Advances in time-domain thermoreflectance. · Amorphous limit to the thermal conductivity of materials. #12;50 nm Interfaces are critical at the nanoscale · Low thermal conductivity in nanostructured

  18. Two-Baryon Systems with Twisted Boundary Conditions

    E-Print Network [OSTI]

    Zohreh Davoudi

    2014-11-07T23:59:59.000Z

    I derive the most general quantization condition for energy eigenvalues of two interacting baryons in a finite cubic volume when arbitrary twisted boundary conditions are imposed on their finite-volume wavefunctions. These quantization conditions are used, along with experimentally known scattering parameters of two-nucleon systems in the coupled 3S1-3D1 channels, to demonstrate the expected effect of a selection of twisted boundary conditions on the spectrum of the deuteron. It is shown that an order of magnitude reduction in the finite-volume corrections to the deuteron binding energy arise in moderate volumes with a proper choice of boundary conditions on the proton and the neutron, or by averaging the result of periodic and anti-periodic boundary conditions. These observations mean that a sub-percent accuracy can be achieved in the determination of the deuteron binding energy at (spatial) volumes as small as ~(9[fm])^3 in upcoming lattice QCD calculations of this nucleus with physical light-quark masses. The results reviewed in this talk are presented in details in Ref. [1].

  19. An Unstable Elliptic Free Boundary Problem arising in Solid Combustion

    E-Print Network [OSTI]

    Monneau, Régis

    An Unstable Elliptic Free Boundary Problem arising in Solid Combustion R. Monneau Ecole Nationale in solid combustion. The maximal solution and every local minimizer of the energy are regular, that is, {u combustion, singularity, unstable problem, Aleksandrov reflection, unique blow-up limit, second variation

  20. BOUNDARY VALUE PROBLEMS FOR THE SHALLOW WATER EQUATIONS WITH TOPOGRAPHY

    E-Print Network [OSTI]

    Temam, Roger

    BOUNDARY VALUE PROBLEMS FOR THE SHALLOW WATER EQUATIONS WITH TOPOGRAPHY MING-CHENG SHIUE, JACQUES LAMINIE, ROGER TEMAM, AND JOSEPH TRIBBIA Abstract. In this article, the nonviscous shallow water equations) for subcritical and supercritical flows are associated with these equations. The semi- discrete cental

  1. Mineralogical effects on the detectability of the postperovskite boundary

    SciTech Connect (OSTI)

    Grocholski, Brent; Catalli, Krystle; Shim, Sang-Heon; Prakapenka, Vitali (MIT); (UC)

    2012-04-02T23:59:59.000Z

    The discovery of a phase transition in Mg-silicate perovskite (Pv) to postperovskite (pPv) at lowermost mantle pressure-temperature (P - T) conditions may provide an explanation for the discontinuous increase in shear wave velocity found in some regions at a depth range of 200 to 400 km above the core-mantle boundary, hereafter the D{double_prime} discontinuity. However, recent studies on binary and ternary systems showed that reasonable contents of Fe{sup 2+} and Al for pyrolite increase the thickness (width of the mixed phase region) of the Pv - pPv boundary (400-600 km) to much larger than the D{double_prime} discontinuity ({le} 70 km). These results challenge the assignment of the D{double_prime} discontinuity to the Pv - pPv boundary in pyrolite (homogenized mantle composition). Furthermore, the mineralogy and composition of rocks that can host a detectable Pv {yields} pPv boundary are still unknown. Here we report in situ measurements of the depths and thicknesses of the Pv {yields} pPv transition in multiphase systems (San Carlos olivine, pyrolitic, and midocean ridge basaltic compositions) at the P - T conditions of the lowermost mantle, searching for candidate rocks with a sharp Pv - pPv discontinuity. Whereas the pyrolitic mantle may not have a seismologically detectable Pv {yields} pPv transition due to the effect of Al, harzburgitic compositions have detectable transitions due to low Al content. In contrast, Al-rich basaltic compositions may have a detectable Pv - pPv boundary due to their distinct mineralogy. Therefore, the observation of the D{prime} discontinuity may be related to the Pv {yields} pPv transition in the differentiated oceanic lithosphere materials transported to the lowermost mantle by subducting slabs.

  2. Search for the decay B^+ \\to K_S^0 K_S^0 \\pi ^+

    SciTech Connect (OSTI)

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, R.N.; Jacobsen, R.G.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Karlsruhe U., EKP /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2009-02-23T23:59:59.000Z

    The authors search for charmless decays of charged B mesons to the three-body final state K{sub S}{sup 0}K{sub S}{sup 0}{pi}{sup +}. Using a data sample of 423.7 fb{sup -1} collected at the {Upsilon}(4S) resonance with the BABAR detector, corresponding to (465.1 {+-} 5.1) x 10{sup 6} B{bar B} pairs, they find no significant signal and determine a 90% confidence level upper limit on the branching fraction of 5.1 x 10{sup -7}.

  3. Topology of the Causal Boundary for Standard Static Spacetimes

    E-Print Network [OSTI]

    Jose' L. Flores; Steven G. Harris

    2006-07-11T23:59:59.000Z

    The topology of the causal boundary for standard static spacetimes--spacetimes time-invariantly conformal to a metric product of the Lorentz line and a Riemannian manifold--is studied in depth. As this is given in terms of a set of real-valued functions on the Riemannian factor, one could use a function-space topology, but physical reasons recommend a chronological topology instead. The function-space topology has a simple product structure, while the chronological topology might not. This paper examines when the chronological topology coincides with the function-space topology and when it has a simple product structure. A class of standard static spacetimes is examined, all of which yield a simple product structure for the causal boundary; the conformal class of these spacetimes includes classical spacetimes such as external Schwarzschild or Reissner-Nordstrom.

  4. Boundary quantum Knizhnik-Zamolodchikov equations and fusion

    E-Print Network [OSTI]

    Nicolai Reshetikhin; Jasper Stokman; Bart Vlaar

    2014-12-19T23:59:59.000Z

    In this paper we extend our previous results concerning Jackson integral solutions of the boundary quantum Knizhnik-Zamolodchikov equations with diagonal K-operators to higher-spin representations of quantum affine $\\mathfrak{sl}_2$. First we give a systematic exposition of known results on $R$-operators acting in the tensor product of evaluation representations in Verma modules over quantum $\\mathfrak{sl}_2$. We develop the corresponding fusion of $K$-operators, which we use to construct diagonal $K$-operators in these representations. We construct Jackson integral solutions of the associated boundary quantum Knizhnik-Zamolodchikov equations and explain how in the finite-dimensional case they can be obtained from our previous results by the fusion procedure.

  5. Warm Bias and Parameterization of Boundary Upwelling in Ocean Models

    SciTech Connect (OSTI)

    Cessi, Paola; Wolfe, Christopher

    2012-11-06T23:59:59.000Z

    It has been demonstrated that Eastern Boundary Currents (EBC) are a baroclinic intensification of the interior circulation of the ocean due to the emergence of mesoscale eddies in response to the sharp buoyancy gradients driven by the wind-stress and the thermal surface forcing. The eddies accomplish the heat and salt transport necessary to insure that the subsurface flow is adiabatic, compensating for the heat and salt transport effected by the mean currents. The EBC thus generated occurs on a cross-shore scale of order 20-100 km, and thus this scale needs to be resolved in climate models in order to capture the meridional transport by the EBC. Our result indicate that changes in the near shore currents on the oceanic eastern boundaries are linked not just to local forcing, such as coastal changes in the winds, but depend on the basin-wide circulation as well.

  6. Kinetically determined shapes of grain boundaries in CVD graphene

    E-Print Network [OSTI]

    Bets, Ksenia V; Yakobson, Boris I

    2014-01-01T23:59:59.000Z

    Predicting the shape of grain boundaries is essential to control results of the growth of large graphene crystals. A global energy minimum search predicting the most stable final structure contradicts experimental observations. Here we present Monte Carlo simulation of kinetic formation of grain boundaries (GB) in graphene during collision of two growing graphene flakes. Analysis of the resulting GBs for the full range of misorientation angles $\\alpha$ allowed us to identify a hidden (from post facto analysis such as microscopy) degree of freedom - the edge misorientation angle $\\beta$. Edge misorientation characterizes initial structure rather than final structure and therefore provides more information about growth conditions. Use of $\\beta$ enabled us to explain disagreements between the experimental observations and theoretical work. Finally, we report an analysis of an interesting special case of zero-tilt GBs for which structure is determined by two variables describing the relative shift of initial isl...

  7. Revisiting Johnson and Jackson boundary conditions for granular flows

    SciTech Connect (OSTI)

    Li, Tingwen; Benyahia, Sofiane

    2012-07-01T23:59:59.000Z

    In this article, we revisit Johnson and Jackson boundary conditions for granular flows. The oblique collision between a particle and a flat wall is analyzed by adopting the classic rigid-body theory and a more realistic semianalytical model. Based on the kinetic granular theory, the input parameter for the partial-slip boundary conditions, specularity coefficient, which is not measurable in experiments, is then interpreted as a function of the particle-wall restitution coefficient, the frictional coefficient, and the normalized slip velocity at the wall. An analytical expression for the specularity coefficient is suggested for a flat, frictional surface with a low frictional coefficient. The procedure for determining the specularity coefficient for a more general problem is outlined, and a working approximation is provided.

  8. A multipoint boundary value problem solver with implicit time stepping

    E-Print Network [OSTI]

    Curtis, Donald Arthur

    1991-01-01T23:59:59.000Z

    University Chair of Advisory Committee: Dr. Ralph E. White A new multipoint boundary value problem solver was developed to solve partial differential equations in one spatial dimension and time or two spatial dimensions with one of them being time... The solution of nonlinear differential equations in engineering requires numerical computation in all but the simplest cases. This research focused on the numerical solution to systems of partial differential equations in one spatial dimension and time...

  9. Spheromak formation and sustainment by tangential boundary flows

    E-Print Network [OSTI]

    García-Martínez, Pablo Luis

    2009-01-01T23:59:59.000Z

    The nonlinear, resistive, 3D magnetohydrodynamic equations are solved numerically to demonstrate the possibility of forming and sustaining a spheromak by forcing tangential flows at the plasma boundary. The method can by explained in terms of helicity injection and differs from other helicity injection methods employed in the past. Several features which were also observed in previous dc helicity injection experiments are identified and discussed.

  10. Examining A Hypersonic Turbulent Boundary Layer at Low Reynolds Number

    E-Print Network [OSTI]

    Semper, Michael Thomas

    2013-05-15T23:59:59.000Z

    z spanwise direction, m Greek Symbols boundary layer thickness, m displacement thickness, m ratio of speci c heats hotwire recovery ratio dynamic viscosity, Pa s density, kg=m3 hotwire overheat ratio, Twire=Tt momentum thickness, m... direct numerical simulation LDV laser doppler velocimetry LES large eddy simulation MTV molecular tagging velocimetry OHR overheat ratio (see ) PIV particle image velocimetry PLIF planar laser induced uorescence RANS Reynolds averaged Navier...

  11. Massive Gravity from Higher Derivative Gravity with Boundary Conditions

    E-Print Network [OSTI]

    Minjoon Park; Lorenzo Sorbo

    2012-10-29T23:59:59.000Z

    With an appropriate choice of parameters, a higher derivative theory of gravity can describe a normal massive sector and a ghost massless sector. We show that, when defined on an asymptotically de Sitter spacetime with Dirichlet boundary conditions, such a higher derivative gravity can provide a framework for a unitary theory of massive gravity in four spacetime dimensions. The resulting theory is free not only of higher derivative ghosts but also of the Boulware-Deser mode.

  12. On the outer boundary of the sunspot penumbra

    E-Print Network [OSTI]

    B. Kalman

    2002-02-06T23:59:59.000Z

    Comparison of photographic observations and vector-magnetograph measurements demonstrate, that the outer boundary of the sunspot penumbra --even in complex sunspot groups-- closely follows the 0.075T isogauss line of the total value of the magnetic field, corresponding approximately to the equipartition value in the photosphere. Radio observations also show this feature. The thick penumbra model with interchange convection (Jahn and Schmidt, 1994) gives the best explanation of the penumbral structure.

  13. Intergranular degradation assessment via random grain boundary network analysis

    DOE Patents [OSTI]

    Kumar, Mukul (San Ramon, CA); Schwartz, Adam J. (Pleasanton, CA); King, Wayne E. (San Ramon, CA)

    2002-01-01T23:59:59.000Z

    A method is disclosed for determining the resistance of polycrystalline materials to intergranular degradation or failure (IGDF), by analyzing the random grain boundary network connectivity (RGBNC) microstructure. Analysis of the disruption of the RGBNC microstructure may be assess the effectiveness of materials processing in increasing IGDF resistance. Comparison of the RGBNC microstructures of materials exposed to extreme operating conditions to unexposed materials may be used to diagnose and predict possible onset of material failure due to

  14. The Ising Model on a Dynamically Triangulated Disk with a Boundary Magnetic Field

    E-Print Network [OSTI]

    Scott McGuire; Simon Catterall; Mark Bowick; Simeon Warner

    2001-05-02T23:59:59.000Z

    We use Monte Carlo simulations to study a dynamically triangulated disk with Ising spins on the vertices and a boundary magnetic field. For the case of zero magnetic field we show that the model possesses three phases. For one of these the boundary length grows linearly with disk area, while the other two phases are characterized by a boundary whose size is on the order of the cut-off. A line of continuous magnetic transitions separates the two small boundary phases. We determine the critical exponents of the continuous magnetic phase transition and relate them to predictions from continuum 2-d quantum gravity. This line of continuous transitions appears to terminate on a line of discontinuous phase transitions dividing the small boundary phases from the large boundary phase. We examine the scaling of bulk magnetization and boundary magnetization as a function of boundary magnetic field in the vicinity of this tricritical point.

  15. Influence of grain boundary energy on the nucleation of complexion transitions

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    Influence of grain boundary energy on the nucleation of complexion transitions Stephanie A different transition tem- peratures. It has been hypothesized that higher energy grain boundaries have relative energies preferentially undergo complexion transitions. Our experiment uses a unique sandwich

  16. A cartesian grid embedded boundary method for the heat equation and poisson's equation in three dimensions

    E-Print Network [OSTI]

    Schwartz, Peter; Barad, Michael; Colella, Phillip; Ligocki, Terry

    2004-01-01T23:59:59.000Z

    A Cartesian grid embedded boundary method for the heatA Cartesian Grid Embedded Boundary Method for the HeatError Grid Size Fig. 17. Solution error for heat equation on

  17. A rigidity result on the ideal boundary structure of smooth space-times

    E-Print Network [OSTI]

    C. J. Fama; C. J. S. Clarke

    1998-06-17T23:59:59.000Z

    Following a survey of the abstract boundary definition of Scott and Szekeres, a rigidity result is proved for the smooth case, showing that the topological structure of the regular part of this boundary in invariantly defined.

  18. Port Hamiltonian Formulation of Infinite Dimensional Systems II. Boundary Control by Interconnection

    E-Print Network [OSTI]

    Schaft, Arjan van der

    Port Hamiltonian Formulation of Infinite Dimensional Systems II. Boundary Control, some new results concerning the boundary control of distributed parameter systems in port Hamiltonian form are presented. The classical finite dimen- sional port Hamiltonian formulation of a dynamical

  19. Immersed Boundary Methods in the Lattice Boltzmann Equation for Flow Simulation

    E-Print Network [OSTI]

    Kang, Shin Kyu

    2012-02-14T23:59:59.000Z

    In this dissertation, we explore direct-forcing immersed boundary methods (IBM) under the framework of the lattice Boltzmann method (LBM), which is called the direct-forcing immersed boundary-lattice Boltzmann method (IB-LBM). First, we derive...

  20. Coupled wake boundary layer model of wind-farms

    E-Print Network [OSTI]

    Stevens, Richard J A M; Meneveau, Charles

    2014-01-01T23:59:59.000Z

    We present and test a coupled wake boundary layer (CWBL) model that describes the distribution of the power output in a wind-farm. The model couples the traditional, industry-standard wake expansion/superposition approach with a top-down model for the overall wind-farm boundary layer structure. The wake expansion/superposition model captures the effect of turbine positioning, while the top-down portion adds the interaction between the wind-turbine wakes and the atmospheric boundary layer. Each portion of the model requires specification of a parameter that is not known a-priori. For the wake model the wake expansion coefficient is required, while the top-down model requires an effective span-wise turbine spacing within which the model's momentum balance is relevant. The wake expansion coefficient is obtained by matching the predicted mean velocity at the turbine from both approaches, while the effective span-wise turbine spacing depends on turbine positioning and thus can be determined from the wake expansion...

  1. Multi-dimensional Longwave Forcing of Boundary Layer Cloud Systems

    SciTech Connect (OSTI)

    Mechem, David B.; Kogan, Y. L.; Ovtchinnikov, Mikhail; Davis, Anthony B; Evans, K. F.; Ellingson, Robert G.

    2008-12-20T23:59:59.000Z

    The importance of multi-dimensional (MD) longwave radiative effects on cloud dynamics is evaluated in a large eddy simulation (LES) framework employing multi-dimensional radiative transfer (Spherical Harmonics Discrete Ordinate Method —SHDOM). Simulations are performed for a case of unbroken, marine boundary layer stratocumulus and a broken field of trade cumulus. “Snapshot” calculations of MD and IPA (independent pixel approximation —1D) radiative transfer applied to LES cloud fields show that the total radiative forcing changes only slightly, although the MD effects significantly modify the spatial structure of the radiative forcing. Simulations of each cloud type employing MD and IPA radiative transfer, however, differ little. For the solid cloud case, relative to using IPA, the MD simulation exhibits a slight reduction in entrainment rate and boundary layer TKE relative to the IPA simulation. This reduction is consistent with both the slight decrease in net radiative forcing and a negative correlation between local vertical velocity and radiative forcing, which implies a damping of boundary layer eddies. Snapshot calculations of the broken cloud case suggest a slight increase in radiative cooling, though few systematic differences are noted in the interactive simulations. We attribute this result to the fact that radiative cooling is a relatively minor contribution to the total energetics. For the cloud systems in this study, the use of IPA longwave radiative transfer is sufficiently accurate to capture the dynamical behavior of BL clouds. Further investigations are required in order to generalize this conclusion for other cloud types and longer time integrations. 1

  2. Improving Subtropical Boundary Layer Cloudiness in the 2011 NCEP GFS

    SciTech Connect (OSTI)

    Fletcher, J. K.; Bretherton, Christopher S.; Xiao, Heng; Sun, Ruiyu N.; Han, J.

    2014-09-23T23:59:59.000Z

    The current operational version of National Centers for Environmental Prediction (NCEP) Global Forecasting System (GFS) shows significant low cloud bias. These biases also appear in the Coupled Forecast System (CFS), which is developed from the GFS. These low cloud biases degrade seasonal and longer climate forecasts, particularly of short-wave cloud radiative forcing, and affect predicted sea surface temperature. Reducing this bias in the GFS will aid the development of future CFS versions and contributes to NCEP's goal of unified weather and climate modelling. Changes are made to the shallow convection and planetary boundary layer parameterisations to make them more consistent with current knowledge of these processes and to reduce the low cloud bias. These changes are tested in a single-column version of GFS and in global simulations with GFS coupled to a dynamical ocean model. In the single-column model, we focus on changing parameters that set the following: the strength of shallow cumulus lateral entrainment, the conversion of updraught liquid water to precipitation and grid-scale condensate, shallow cumulus cloud top, and the effect of shallow convection in stratocumulus environments. Results show that these changes improve the single-column simulations when compared to large eddy simulations, in particular through decreasing the precipitation efficiency of boundary layer clouds. These changes, combined with a few other model improvements, also reduce boundary layer cloud and albedo biases in global coupled simulations.

  3. Spontaneous free-boundary structure in crumpled membranes

    E-Print Network [OSTI]

    T. A. Witten

    2008-11-22T23:59:59.000Z

    We investigate the strong curvature that appears at the boundaries of a thin crumpled elastic membrane. We account for these high-curvature regions in terms of the stretching-ridge singularity believed to dominate the structure of strongly deformed elastic membranes. Using a membrane fastened to itself to form a bag shape with a single stretching ridge, we show that the creation of points of high boundary curvature lowers the interior ridge's energy. In the limit of small thickness, the induced curvature becomes arbitrarily strong on the scale of the object size and results in sharp edges connecting interior vertices to the boundary. REVISED: We analyze these edges as conical sectors with no stretching. As the membrane size diverges, the edge energy grows as the square root of the central ridge energy. For comparison, we discuss the effect of truncating a stretching ridge at its ends. The effect of truncation becomes appreciable when the truncation length is comparable to the width of the untruncated ridge.

  4. Impact of boundaries on velocity profiles in bubble rafts

    E-Print Network [OSTI]

    Yuhong Wang; Kapilanjan Krishan; Michael Dennin

    2006-01-31T23:59:59.000Z

    Under conditions of sufficiently slow flow, foams, colloids, granular matter, and various pastes have been observed to exhibit shear localization, i.e. regions of flow coexisting with regions of solid-like behavior. The details of such shear localization can vary depending on the system being studied. A number of the systems of interest are confined so as to be quasi-two dimensional, and an important issue in these systems is the role of the confining boundaries. For foams, three basic systems have been studied with very different boundary conditions: Hele-Shaw cells (bubbles confined between two solid plates); bubble rafts (a single layer of bubbles freely floating on a surface of water); and confined bubble rafts (bubbles confined between the surface of water below and a glass plate on top). Often, it is assumed that the impact of the boundaries is not significant in the ``quasi-static limit'', i.e. when externally imposed rates of strain are sufficiently smaller than internal kinematic relaxation times. In this paper, we directly test this assumption for rates of strain ranging from $10^{-3}$ to $10^{-2} {\\rm s^{-1}}$. This corresponds to the quoted quasi-static limit in a number of previous experiments. It is found that the top plate dramatically alters both the velocity profile and the distribution of nonlinear rearrangements, even at these slow rates of strain.

  5. Comment on “Velocity boundary conditions at a tokamak resistive wall” [Phys. Plasmas 21, 032506 (2014)

    SciTech Connect (OSTI)

    Zakharov, Leonid E. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States); Li, Xujing [Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing (China)

    2014-09-15T23:59:59.000Z

    The paper gives the derivation of the MHD boundary condition for the plasma flow to the wall during disruptions.

  6. Grain boundary microstructure, chemistry, and IGSCC in Alloy 600 and Alloy 690

    SciTech Connect (OSTI)

    Norring, K. [Studsvik AB, Nykoeping (Sweden); Stiller, K. [Chalmers Univ. of Technology, Goeteborg (Sweden); Nilsson, J.O. [AB Sandvik Steel, Sandviken (Sweden)

    1992-12-31T23:59:59.000Z

    The resistance to intergranular stress corrosion cracking of six different Alloy 600 and Alloy 690 steam generator tubes has been investigated. The composition of the materials at grain boundaries has been investigated using analytical transmission electron microscopy and atom probe field ion microscopy techniques. The depletion of chromium at the grain boundaries has been related to the type of grain boundary precipitates. Segregation of carbon and boron to the grain boundaries has been observed and quantified.

  7. On the limit of large surface tension for a fluid motion with free boundary

    E-Print Network [OSTI]

    Marcelo M. Disconzi; David G. Ebin

    2014-03-25T23:59:59.000Z

    We study the free boundary Euler equations in two spatial dimensions. We prove that if the boundary is sufficiently regular, then solutions of the free boundary fluid motion converge to solutions of the Euler equations in a fixed domain when the coefficient of surface tension tends to infinity.

  8. AUTOMATIC EXTRACTION OF THE OPTIC DISC BOUNDARY FOR DETECTING RETINAL DISEASES

    E-Print Network [OSTI]

    Li, Baihua

    AUTOMATIC EXTRACTION OF THE OPTIC DISC BOUNDARY FOR DETECTING RETINAL DISEASES Muhammad Salman shape model for the extraction of Optic Disc boundary. The determination of Optic Disc boundary used as a reference point to lo- cate other retinal structures, and any structural change in Optic Disc

  9. Predictive Inner-Outer Model for Turbulent Boundary Layers Applied to Hypersonic DNS Data

    E-Print Network [OSTI]

    Martín, Pino

    Predictive Inner-Outer Model for Turbulent Boundary Layers Applied to Hypersonic DNS Data Clara numerical simulation (DNS) data of supersonic and hypersonic turbulent boundaries with Mach 3 and Mach 7, and Martin12­14 on DNS of hypersonic turbulent boundary layers demonstrates the existence of large scale

  10. Dielectric Boundary Force in Molecular Solvation with the PoissonBoltzmann Free Energy: A Shape

    E-Print Network [OSTI]

    Li, Bo

    Dielectric Boundary Force in Molecular Solvation with the Poisson­Boltzmann Free Energy: A Shape boundary force acting on such a boundary is the negative first variation of the elec- trostatic free energy [17,18,35,43,44]. Such a predefined interface is used to compute the solvation free energy as the sum

  11. A Study of the Grain Boundaries and Hydrogen in HF-CVD Diamond Films

    E-Print Network [OSTI]

    Adler, Joan

    composition of grain boundaries in polycrystalline diamond lms by transmission electron microscopy and highA Study of the Grain Boundaries and Hydrogen in HF-CVD Diamond Films Israel Yoel Koenka #12;A Study of the Grain Boundaries and Hydrogen in HF-CVD Diamond Films Research Thesis In partial fulllment

  12. BOUNDARY LAYER (BL) THERMAL EDDIES OVER A PINE FOREST FROM CARES 2010

    E-Print Network [OSTI]

    BOUNDARY LAYER (BL) THERMAL EDDIES OVER A PINE FOREST FROM CARES 2010 Gunnar Senum and Stephen are three thermal eddies, about 250 meters wide, in the boundary layer. These thermal eddies are formed from the solar heating of the surface and help to form the boundary layer. The eddy updrafts are transporting

  13. Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly

    E-Print Network [OSTI]

    Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly Circular Plasma Boundary H. Qin A. Reiman September 25, 1996 Abstract An analytic solution is obtained for free. In the absence of surface currents at the plasma­vacuum in­ terface, the free­boundary equilibrium solution

  14. Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly

    E-Print Network [OSTI]

    Free Boundary, High Beta Equilibrium in a Large Aspect Ratio Tokamak with Nearly Circular Plasma Boundary H. Qin A. Reiman September 25, 1996 Abstract An analytic solution is obtained for free. In the absence of surface currents at the plasma-vacuum in- terface, the free-boundary equilibrium solution

  15. Journal of Computational Acoustics, Vol. 8, No. 1 (2000) 139156 CONTINUED-FRACTION ABSORBING BOUNDARY CONDITIONS

    E-Print Network [OSTI]

    Guddati, Murthy N.

    of the Engquist-Majda boundary conditions, their practical success is limited by the difficulties posed-FRACTION ABSORBING BOUNDARY CONDITIONS FOR THE WAVE EQUATION MURTHY N. GUDDATI Department of Civil Engineering, North Revised 1 October 1999 Absorbing boundary conditions are generally required for numerical modeling of wave

  16. Singular limits of a two-dimensional boundary value problem arising in corrosion modelling

    E-Print Network [OSTI]

    Ceragioli, Francesca

    Singular limits of a two-dimensional boundary value problem arising in corrosion modelling Juan D boundary . A very common boundary condition arising in corrosion modelling in a planar sample represented u on . We refer the reader to [11] and [4] for the derivation of this and related corrosion models

  17. A case study of boundary layer ventilation by convection and coastal processes

    E-Print Network [OSTI]

    Dacre, Helen

    of the pollution in the atmosphere originates from emissions in the atmospheric boundary layer, the region; published 12 September 2007. [1] It is often assumed that ventilation of the atmospheric boundary layer responsible for ventilation of the atmospheric boundary layer during a nonfrontal day that occurred on 9 May

  18. Effects of temperature and disorder on thermal boundary conductance at solidsolid interfaces: Nonequilibrium

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    with the constituent materials. The inter- face thermal resistance, often referred to as thermal boundary resistance between two different materials when a heat flux is applied. The inverse of thermal boundary resistance mismatched interfaces. Ã? 2007 Elsevier Ltd. All rights reserved. Keywords: Thermal boundary resistance

  19. GRAIN BOUNDARY EVOLUTION: NEW PERSPECTIVES M. EMELIANENKO, D. GOLOVATY, D. KINDERLEHRER, AND S. TA'ASAN

    E-Print Network [OSTI]

    that they are robust but they are not strongly related to energetics. Recent work has provided us with a new statisticGRAIN BOUNDARY EVOLUTION: NEW PERSPECTIVES M. EMELIANENKO, D. GOLOVATY, D. KINDERLEHRER, AND S. TA boundaries. The energetics and connectivity of the net- work of boundaries are implicated in many properties

  20. Grain boundary structure and solute segregation in titanium-doped sapphire bicrystals

    SciTech Connect (OSTI)

    Taylor, Seth T.

    2002-05-17T23:59:59.000Z

    Solute segregation to ceramic grain boundaries governs material processing and microstructure evolution, and can strongly influence material properties critical to engineering performance. Understanding the evolution and implications of grain boundary chemistry is a vital component in the greater effort to engineer ceramics with controlled microstructures. This study examines solute segregation to engineered grain boundaries in titanium-doped sapphire (Al2O3) bicrystals, and explores relationships between grain boundary structure and chemistry at the nanometer scale using spectroscopic and imaging techniques in the transmission electron microscope (TEM). Results demonstrate dramatic changes in solute segregation stemming from small fluctuations in grain boundary plane and structure. Titanium and silicon solute species exhibit strong tendencies to segregate to non-basal and basal grain boundary planes, respectively. Evidence suggests that grain boundary faceting occurs in low-angle twis t boundaries to accommodate nonequilibrium solute segregation related to slow specimen cooling rates, while faceting of tilt grain boundaries often occurs to expose special planes of the coincidence site lattice (CSL). Moreover, quantitative analysis of grain boundary chemistry indicates preferential segregation of charged defects to grain boundary dislocations. These results offer direct proof that static dislocations in ionic materials can assume a net charge, and emphasize the importance of interactions between charged point, line, and planar defects in ionic materials. Efforts to understand grain boundary chemistry in terms of space charge theory, elastic misfit and nonequilibrium segregation are discussed for the Al2O3 system.

  1. Control of the ocean circulation by boundaries and topography P.B. Rhines

    E-Print Network [OSTI]

    energy in the ocean circulation is dominated by boundary currents, zonal jets and mesoscale eddies. Kinetic energy generates enstrophy at a western ocean boundary and destroys it at an eastern boundary, or nonlinear baroclinic Rossby waves) dominate the surface kinetic energy of the world ocean

  2. Warren Wiebe Oral History

    E-Print Network [OSTI]

    Wiebe, Warren; Roane, Jordan

    2014-01-01T23:59:59.000Z

    Oral history interview of Warren Wiebe conducted by Jordan Roane in Lawrence, Kansas, on November 12, 2014. Warren grew up in the small western Kansas town of Hillsboro. Hillsboro is known for its Mennonite community as ...

  3. Crystallographic Characteristics of Grain Boundaries in Dense Yttria-Stabilized Zirconia

    SciTech Connect (OSTI)

    Lam Helmick; Shen J. Dillon; Kirk Gerdes; Randall Gemmen; Gregory S. Rohrer; Sridhar Seetharaman; Paul A. Salvador

    2010-04-01T23:59:59.000Z

    Grain-boundary plane, misorientation angle, grain size, and grain-boundary energy distributions were quantified using electron backscatter diffraction data for dense polycrystalline yttria-stabilized zirconia, to understand interfacial crystallography in solid oxide fuel cells. Tape-cast samples were sintered at 14501C for 4 h and annealed for at least 100 h between 8001C and 16501C. Distributions obtained from both three-dimensional (3D) reconstructions and stereological analyses of 2D sections demonstrated that the (100) boundary planes {(111)} have relative areas larger {smaller} than expected in a random distribution, and that the boundary plane distribution is inversely correlated to the boundary energy distribution.

  4. The representation of boundary currents in a finite element shallow water model

    E-Print Network [OSTI]

    Düben, Peter D

    2015-01-01T23:59:59.000Z

    We evaluate the influence of local resolution, eddy viscosity, coastline structure, and boundary conditions on the numerical representation of boundary currents in a finite element shallow-water model. The use of finite element discretization methods offers a higher flexibility compared to finite difference and finite volume methods, that are mainly used in previous publications. This is true for the geometry of the coast lines and for the realization of boundary conditions. For our investigations we simulate steady separation of western boundary currents from idealized and realistic coast lines. The use of grid refinement allows a detailed investigation of boundary separation at reasonable numerical cost.

  5. Linking Grain Boundary Structure and Composition to Intergranular Stress Corrosion Cracking of Austenitic Stainless Steels

    SciTech Connect (OSTI)

    Bruemmer, Stephen M.

    2004-08-10T23:59:59.000Z

    Grain boundary structure and composition is assessed in austenitic stainless steels along with its influence on intergranular stress corrosion cracking (IGSCC) in high-temperature water. Brief examples are presented illustrating effects of grain boundary character and segregation on behavior in specific light-water-reactor environments. Although grain boundary engineering can produce an increased fraction of special boundaries in austenitic stainless alloys, practical benefits depend on the boundary orientation distribution. It is critical to recognize that only coherent sigma 3s appear to be resistant to SCC and the behavior of other low sigma boundaries is uncertain. Grain boundary composition can have a dominant effect on IGSCC under certain conditions, but altered interfacial chemistry is not required for cracking. In high-potential oxidizing environments, IGSCC susceptibility is a direct function of the boundary Cr concentration. Non-equilibrium thermal segregation of Cr and Mo is often present in millannealed stainless steels and may influence cracking susceptibility. This initial grain boundary composition alters subsequent radiation-induced segregation and delays irradiation-assisted SCC susceptibility to higher doses. Other alloying elements and impurities in 300-series stainless steels have been seen to enrich grain boundaries, but few have any significant impact on IGSCC susceptibility. One exception is Si that strongly segregates during irradiation. recent results suggest that Si may accelerate crack propagation in both low- and high-potential water environments. Critical research is still needed to isolate individual grain boundary characteristics and quantitatively link to IGSCC.

  6. Turbine exhaust diffuser with region of reduced flow area and outer boundary gas flow

    DOE Patents [OSTI]

    Orosa, John

    2014-03-11T23:59:59.000Z

    An exhaust diffuser system and method for a turbine engine. The outer boundary may include a region in which the outer boundary extends radially inwardly toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. At least one gas jet is provided including a jet exit located on the outer boundary. The jet exit may discharge a flow of gas downstream substantially parallel to an inner surface of the outer boundary to direct a portion of the exhaust flow in the diffuser toward the outer boundary to effect a radially outward flow of at least a portion of the exhaust gas flow toward the outer boundary to balance an aerodynamic load between the outer and inner boundaries.

  7. Role of the basin boundary conditions in gravity wave turbulence

    E-Print Network [OSTI]

    Luc Deike; Benjamin Miquel; Pablo Gutiérrez-Matus; Timothée Jamin; Benoit Semin; Sébastien Aumaitre; Michael Berhanu; Eric Falcon; Félicien BONNEFOY

    2014-12-16T23:59:59.000Z

    Gravity wave turbulence is studied experimentally in a large wave basin where irregular waves are generated unidirectionally. The role of the basin boundary conditions (absorbing or reflecting) and of the forcing properties are investigated. To that purpose, an absorbing sloping beach opposite to the wavemaker can be replaced by a reflecting vertical wall. We observe that the wave field properties depend strongly on these boundary conditions. Quasi-one dimensional field of nonlinear waves propagate before to be damped by the beach whereas a more multidirectional wave field is observed with the wall. In both cases, the wave spectrum scales as a frequency-power law with an exponent that increases continuously with the forcing amplitude up to a value close to -4, which is the value predicted by the weak turbulence theory. The physical mechanisms involved are probably different according to the boundary condition used, but cannot be easily discriminated with only temporal measurements. We have also studied freely decaying gravity wave turbulence in the closed basin. No self-similar decay of the spectrum is observed, whereas its Fourier modes decay first as a time power law due to nonlinear mechanisms, and then exponentially due to linear viscous damping. We estimate the linear, nonlinear and dissipative time scales to test the time scale separation that highlights the important role of a large scale Fourier mode. By estimation of the mean energy flux from the initial decay of wave energy, the Kolmogorov-Zakharov constant is evaluated and found to be compatible with a recent theoretical value.

  8. Spin connection and boundary states in a topological insulator

    E-Print Network [OSTI]

    V. Parente; P. Lucignano; P. Vitale; A. Tagliacozzo; F. Guinea

    2010-11-02T23:59:59.000Z

    We study the surface resistivity of a three-dimensional topological insulator when the boundaries exhibit a non trivial curvature. We obtain an analytical solution for a spherical topological insulator, and we show that a non trivial quantum spin connection emerges from the three dimensional band structure. We analyze the effect of the spin connection on the scattering by a bump on a flat surface. Quantum effects induced by the geometry lead to resonances when the electron wavelength is comparable to the size of the bump.

  9. Transverse gravity-capillary waves near a vibrating boundary

    E-Print Network [OSTI]

    Wells, Codie Shaffer

    2012-06-07T23:59:59.000Z

    ' . dne ~ 5y tahon cf See eu5haxntonkc or harnomdc feature of the particular ' oscRatojy mode kn'tineethm. ' ~ non-linear wave phenomena, vddqh caphty the anhharnonic feature, have heen noted hy Faraday and Taylor. The enharmonic ?nd other harmonic... mechaxdsin, an unusual trans- verse boundary wave was noted along the ~ surface of the plunger. Gbser- vutions of a simQar nature bsd apparently been made by Faraday [1831 ] and . 1 . Taylor f 1%3 I ~gravity-capillary~ gravdty ~, -respectively; F...

  10. Educing the volume out of the phase space boundary

    E-Print Network [OSTI]

    Manuel A. Cobas; M. A. R. Osorio; María Suárez

    2005-09-26T23:59:59.000Z

    We explicitly show that, in a system with T-duality symmetry, the configuration space volume degrees of freedom may hide on the surface boundary of the region of accessible states with energy lower than a fixed value. This means that, when taking the decompactification limit (big volume limit), a number of accessible states proportional to the volume is recovered even if no volume dependence appears when energy is high enough. All this behavior is contained in the exact way of computing sums by making integrals. We will also show how the decompactification limit for the gas of strings can be defined in a microcanonical description at finite volume.

  11. The gradient flow running coupling with twisted boundary conditions

    E-Print Network [OSTI]

    A. Ramos

    2014-09-04T23:59:59.000Z

    We study the gradient flow for Yang-Mills theories with twisted boundary conditions. The perturbative behavior of the energy density $\\langle E(t)\\rangle$ is used to define a running coupling at a scale given by the linear size of the finite volume box. We compute the non-perturbative running of the pure gauge $SU(2)$ coupling constant and conclude that the technique is well suited for further applications due to the relatively mild cutoff effects of the step scaling function and the high numerical precision that can be achieved in lattice simulations. We also comment on the inclusion of matter fields.

  12. Conformally covariant boundary correlation functions with a quantum group

    E-Print Network [OSTI]

    Kalle Kytölä; Eveliina Peltola

    2014-10-23T23:59:59.000Z

    Particular boundary correlation functions of conformal field theory are needed to answer some questions related to random conformally invariant curves known as Schramm-Loewner evolutions (SLE). In this article, we introduce a correspondence and establish its fundamental properties, which are used in companion articles for explicitly solving two such problems. The correspondence associates Coulomb gas type integrals to vectors in a tensor product representation of a quantum group, a q-deformation of the Lie algebra sl2. We show that desired properties of the functions are guaranteed by natural representation theoretical properties of the vectors.

  13. Transition in Hypersonic Boundary Layers: Role of Dilatational Waves

    E-Print Network [OSTI]

    Zhu, Yiding; Yuan, Huijing; Wu, Jiezhi; Chen, Shiyi; Lee, Cunbiao; Gad-el-Hak, Mohamed

    2015-01-01T23:59:59.000Z

    Transition and turbulence production in a hypersonic boundary layer is investigated in a Mach 6 quiet wind tunnel using Rayleigh-scattering visualization, fast-response pressure measurements, and particle image velocimetry. It is found that the second instability acoustic mode is the key modulator of the transition process. The second mode experiences a rapid growth and a very fast annihilation due to the effect of bulk viscosity. The second mode interacts strongly with the first vorticity mode to directly promote a fast growth of the latter and leads to immediate transition to turbulence.

  14. EART 265 Lecture Notes: Boundary Layers We're interested here mainly in boundary layers relevant to planets, i.e. those of planetary atmo-

    E-Print Network [OSTI]

    Nimmo, Francis

    of the bounding surface. Note that the vertical shear caused by the surface generates turbulence, whichEART 265 Lecture Notes: Boundary Layers We're interested here mainly in boundary layers relevant and the surface, thus mediating all interactions between the two. If we look back at the Navier-Stokes equations

  15. Laminar-turbulent separatrix in a boundary layer flow

    E-Print Network [OSTI]

    Biau, Damien

    2013-01-01T23:59:59.000Z

    The transitional boundary layer flow over a flat plate is investigated. The boundary layer flow is known to develop unstable Tollmien-Schlichting waves above a critical value of the Reynolds number. However, it is also known that this transition can be observed for sub-critical Reynolds numbers. In that case, the basin of attraction of the laminar state coexists with the sustained turbulence. In this article, the trajectory on the separatrix between these two states is simulated. The state on the separatrix is independent from the initial condition and is dynamically connected to both the laminar flow and the turbulence. Such an edge state provides information regarding the basic features of the transitional flow. The solution takes the form of a low speed streak, flanked by two quasi-streamwise sinuous vortices. The shape of the streaks is close to that simulated with the linear optimal perturbation method. This solution is compared to existing results concerning streak breakdown. The simulations are realize...

  16. Classical universes of the no-boundary quantum state

    SciTech Connect (OSTI)

    Hartle, James B. [Department of Physics, University of California, Santa Barbara, CA 93106-9530 (United States); Hawking, S. W. [DAMTP, CMS, Wilberforce Road, CB3 0WA Cambridge (United Kingdom); Hertog, Thomas [Laboratoire APC, 10 rue A. Domon et L. Duquet, 75205 Paris (France) and International Solvay Institutes, Boulevard du Triomphe, ULB, C.P. 231, 1050 Brussels (Belgium)

    2008-06-15T23:59:59.000Z

    We analyze the origin of the quasiclassical realm from the no-boundary proposal for the Universe's quantum state in a class of minisuperspace models. The models assume homogeneous, isotropic, closed spacetime geometries, a single scalar field moving in a quadratic potential, and a fundamental cosmological constant. The allowed classical histories and their probabilities are calculated to leading semiclassical order. For the most realistic range of parameters analyzed, we find that a minimum amount of scalar field is required, if there is any at all, in order for the Universe to behave classically at late times. If the classical late time histories are extended back, they may be singular or bounce at a finite radius. The ensemble of classical histories is time symmetric although individual histories are generally not. The no-boundary proposal selects inflationary histories, but the measure on the classical solutions it provides is heavily biased towards small amounts of inflation. However, the probability for a large number of e-foldings is enhanced by the volume factor needed to obtain the probability for what we observe in our past light cone, given our present age. Our results emphasize that it is the quantum state of the Universe that determines whether or not it exhibits a quasiclassical realm and what histories are possible or probable within that realm.

  17. Plasma Transport at the Magnetospheric Flank Boundary. Final report

    SciTech Connect (OSTI)

    Otto, Antonius

    2012-04-23T23:59:59.000Z

    Progress is highlighted in these areas: 1. Model of magnetic reconnection induced by three-dimensional Kelvin Helmholtz (KH) modes at the magnetospheric flank boundary; 2. Quantitative evaluation of mass transport from the magnetosheath onto closed geomagnetic field for northward IMF; 3. Comparison of mass transfer by cusp reconnection and Flank Kelvin Helmholtz modes; 4. Entropy constraint and plasma transport in the magnetotail - a new mechanism for current sheet thinning; 5. Test particle model for mass transport onto closed geomagnetic field for northward IMF; 6. Influence of density asymmetry and magnetic shear on (a) the linear and nonlinear growth of 3D Kelvin Helmholtz (KH) modes, and (b) three-dimensional KH mediated mass transport; 7. Examination of entropy and plasma transport in the magnetotail; 8. Entropy change and plasma transport by KH mediated reconnection - mixing and heating of plasma; 9. Entropy and plasma transport in the magnetotail - tail reconnection; and, 10. Wave coupling at the magnetospheric boundary and generation of kinetic Alfven waves.

  18. ARM: ARSCL: cloud boundaries from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Coulter, Richard; Widener, Kevin; Bharadwaj, Nitin; Johnson, Karen; Martin, Timothy

    ARSCL: cloud boundaries from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

  19. Optical boundary reconstruction of tokamak plasmas for feedback control of plasma position and shape

    SciTech Connect (OSTI)

    Hommen, G.; Baar, M. de [Control Systems Technology Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); FOM Institute for Plasma Physics ''Rijnhuizen'', Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Nuij, P.; Steinbuch, M. [Control Systems Technology Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); McArdle, G.; Akers, R. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom)

    2010-11-15T23:59:59.000Z

    A new diagnostic is developed to reconstruct the plasma boundary using visible wavelength images. Exploiting the plasma's edge localized and toroidally symmetric emission profile, a new coordinate transform is presented to reconstruct the plasma boundary from a poloidal view image. The plasma boundary reconstruction is implemented in MATLAB and applied to camera images of Mega-Ampere Spherical Tokamak discharges. The optically reconstructed plasma boundaries are compared to magnetic reconstructions from the offline reconstruction code EFIT, showing very good qualitative and quantitative agreement. Average errors are within 2 cm and correlation is high. In the current software implementation, plasma boundary reconstruction from a single image takes 3 ms. The applicability and system requirements of the new optical boundary reconstruction, called OFIT, for use in both feedback control of plasma position and shape and in offline reconstruction tools are discussed.

  20. Lie and conditional symmetries of a class of nonlinear (1+2)-dimensional boundary value problems

    E-Print Network [OSTI]

    Roman Cherniha; John R King

    2014-12-22T23:59:59.000Z

    A new definition of conditional invariance for boundary value problems involving a wide range of boundary conditions (including initial value problems as a special case) is proposed. It is shown that other definitions worked out in order to find Lie symmetries of boundary value problems with standard boundary conditions, follow as particular cases from our definition. Simple examples of direct applicability to the nonlinear problems arising in applications are demonstrated. Moreover, the successful application of the definition for the Lie and conditional symmetry classification of a class of (1+2)-dimensional nonlinear boundary value problems governed by the nonlinear diffusion equation in a semi-infinite domain is realised. In particular, it is proved that there is a special exponent, $k=-2$, for the power diffusivity $u^k$ when the problem in question with non-vanishing flux on the boundary admits additional Lie symmetry operators compared to the case $k\

  1. Consideration of Grain Size Distribution in the Diffusion of Fission Gas to Grain Boundaries

    SciTech Connect (OSTI)

    Paul C. Millett; Yongfeng Zhang; Michael R. Tonks; S. B. Biner

    2013-09-01T23:59:59.000Z

    We analyze the accumulation of fission gas on grain boundaries in a polycrystalline microstructure with a distribution of grain sizes. The diffusion equation is solved throughout the microstructure to evolve the gas concentration in space and time. Grain boundaries are treated as infinite sinks for the gas concentration, and we monitor the cumulative gas inventory on each grain boundary throughout time. We consider two important cases: first, a uniform initial distribution of gas concentration without gas production (correlating with post-irradiation annealing), and second, a constant gas production rate with no initial gas concentration (correlating with in-reactor conditions). The results show that a single-grain-size model, such as the Booth model, over predicts the gas accumulation on grain boundaries compared with a polycrystal with a grain size distribution. Also, a considerable degree of scatter, or variability, exists in the grain boundary gas accumulation when comparing all of the grain boundaries in the microstructure.

  2. Supersonic Downflows at the Umbra-Penumbra Boundary of Sunspots

    E-Print Network [OSTI]

    Louis, Rohan E; Mathew, Shibu K; Venkatakrishnan, P

    2010-01-01T23:59:59.000Z

    High resolution spectropolarimetric observations of 3 sunspots taken with {\\em Hinode} demonstrate the existence of supersonic downflows at or close to the umbra-penumbra boundary which have not been reported before. These downflows are confined to large patches, usually encompassing bright penumbral filaments, and have lifetimes of more than 14 hr. The presence of strong downflows in the center-side penumbra near the umbra rules out an association with the Evershed flow. Chromospheric filtergrams acquired close to the time of the spectropolarimetric measurements show large, strong, and long-lived brightenings in the neighborhood of the downflows. The photospheric intensity also exhibit persistent brightenings comparable to the quiet Sun. Interestingly, the orientation of the penumbral filaments at the site of the downflows is similar to that resulting from the reconnection process described by \\citet{Ryutova2008a}. The existence of such downflows in the inner penumbra represents a challenge for numerical mod...

  3. The boundary of Gödel's spacetime and the chronology protection conjecture

    E-Print Network [OSTI]

    P. Pitanga

    2012-01-09T23:59:59.000Z

    We present a homogenous anisotropic conformal spacetime manifold that provide an example of Hawking's chronology protection conjecture in three-dimensional gravity theory. The solution is based upon the fact that the seven-dimensional group of the automorphism of the Heisenberg motion group H1{\\times}U(1), modulo discrete sub-group \\Gamma, is the symmetry group of the sub-Riemannian (SR)- manifold, boundary of the Cauchy-Riemann (CR)-manifold, allowing the existence of positive mass, momentum, angular-momentum and timelike-translation. It is shown that many mirror symmetric self-similar G\\"odel's surfaces are hidden behind a Cauchy spacelike surface so that causality violation is not visible from outside.

  4. An immersed boundary model of the cochlea with parametric forcing

    E-Print Network [OSTI]

    Ko, William

    2015-01-01T23:59:59.000Z

    The cochlea or inner ear has a remarkable ability to amplify sound signals. This is understood to derive at least in part from some active process that magnifies vibrations of the basilar membrane (BM) and the cochlear partition in which it is embedded, to the extent that it overcomes the effect of viscous damping from the surrounding cochlear fluid. Many authors have associated this amplification ability to some type of mechanical resonance within the cochlea, however there is still no consensus regarding the precise cause of amplification. Our work is inspired by experiments showing that the outer hair cells within the cochlear partition change their lengths when stimulated, which can in turn cause periodic distortions of the BM and other structures in the cochlea. This paper investigates a novel fluid-mechanical resonance mechanism that derives from hydrodynamic interactions between an oscillating BM and the surrounding cochlear fluid. We present a model of the cochlea based on the immersed boundary method...

  5. The Lithium Depletion Boundary as a Clock and Thermometer

    E-Print Network [OSTI]

    R. D. Jeffries; T. Naylor

    2000-09-12T23:59:59.000Z

    We take a critical look at the lithium depletion boundary (LDB) technique that has recently been used to derive the ages of open clusters. We identify the sources of experimental and systematic error and show that the probable errors are larger by approximately a factor two than presently claimed in the literature. We then use the Pleiades LDB age and photometry in combination with evolutionary models to define empirical colour-T_eff relations that can be applied to younger clusters. We find that these relationships DO NOT produce model isochrones that match the younger cluster data. We propose that this is due either to systematic problems in the evolutionary models or an age (gravity) sensitivity in the colour-T_eff relation which is not present in published atmospheric models.

  6. Free boundary conditions and the AdS$_3$/CFT$_2$ correspondence

    E-Print Network [OSTI]

    Luis Apolo; Massimo Porrati

    2014-04-01T23:59:59.000Z

    We show that the recently proposed free boundary conditions for AdS$_3$ are dual to two-dimensional quantum gravity in certain fixed gauges. In particular, we note that an appropriate identification of the generator of Virasoro transformations leads to a vanishing total central charge in agreement with the theory at the boundary. We argue that this identification is necessary to match the bulk and boundary generators of Virasoro transformations and for consistency with the constraint equations.

  7. Prediction of potential and current density distribution using the boundary element method

    E-Print Network [OSTI]

    Pakalapati, Surya Narayana Raju

    1992-01-01T23:59:59.000Z

    boundary. 12 7. Discontinuous 2D boundary elements in intrinsic coordinate system. . . . . 25 8. Discontinuous 3D linear (boundary) element (a) global coordinates (b) intrinsic coordinates. 30 9. A simple galvanic corrosion couple (potential field... in two dimensions). . . 35 10. Potential distribution along the surface of the electrodes (i. e. , at yW). . . . 38 11. A simple problem of a cube (potential field in three dimensions). . . , . . . 41 12. Corrosion cell (a) perspective (b) cross...

  8. The growth mechanism of grain boundary carbide in Alloy 690

    SciTech Connect (OSTI)

    Li, Hui, E-mail: huili@shu.edu.cn [Key Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China); Institute of Materials, Shanghai University, Shanghai 200072 (China); Xia, Shuang; Zhou, Bangxin [Institute of Materials, Shanghai University, Shanghai 200072 (China); Peng, Jianchao [Key Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China)

    2013-07-15T23:59:59.000Z

    The growth mechanism of grain boundary M{sub 23}C{sub 6} carbides in nickel base Alloy 690 after aging at 715 °C was investigated by high resolution transmission electron microscopy. The grain boundary carbides have coherent orientation relationship with only one side of the matrix. The incoherent phase interface between M{sub 23}C{sub 6} and matrix was curved, and did not lie on any specific crystal plane. The M{sub 23}C{sub 6} carbide transforms from the matrix phase directly at the incoherent interface. The flat coherent phase interface generally lies on low index crystal planes, such as (011) and (111) planes. The M{sub 23}C{sub 6} carbide transforms from a transition phase found at curved coherent phase interface. The transition phase has a complex hexagonal crystal structure, and has coherent orientation relationship with matrix and M{sub 23}C{sub 6}: (111){sub matrix}//(0001){sub transition}//(111){sub carbide}, <112{sup ¯}>{sub matrix}//<21{sup ¯}10>{sub transition}//<112{sup ¯}>{sub carbide}. The crystal lattice constants of transition phase are c{sub transition}=?(3)×a{sub matrix} and a{sub transition}=?(6)/2×a{sub matrix}. Based on the experimental results, the growth mechanism of M{sub 23}C{sub 6} and the formation mechanism of transition phase are discussed. - Highlights: • A transition phase was observed at the coherent interfaces of M{sub 23}C{sub 6} and matrix. • The transition phase has hexagonal structure, and is coherent with matrix and M{sub 23}C{sub 6}. • The M{sub 23}C{sub 6} transforms from the matrix directly at the incoherent phase interface.

  9. E-Print Network 3.0 - algebraic boundary representations Sample...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Collection: Mathematics 94 Algebraic Holography K.H. Rehren Summary: that in contrast, an identification between the algebras generated by the respective local bulk and boundary...

  10. Discrete Group Actions on Spacetimes: Causality Conditions and the Causal Boundary

    E-Print Network [OSTI]

    Steven G. Harris

    2003-10-14T23:59:59.000Z

    Suppose a spacetime $M$ is a quotient of a spacetime $V$ by a discrete group of isometries. It is shown how causality conditions in the two spacetimes are related, and how can one learn about the future causal boundary on $M$ by studying structures in $V$. The relations between the two are particularly simple (the boundary of the quotient is the quotient of the boundary) if both $V$ and $M$ have spacelike future boundaries and if it is known that the quotient of the future completion of $V$ is past-distinguishing. (That last assumption is automatic in the case of $M$ being multi-warped.)

  11. Sensitivity analysis of aquifer parameter estimations based on the Laplace equation with linearized boundary conditions

    E-Print Network [OSTI]

    Szilagyi, Jozsef

    boundary conditions Jozsef Szilagyi Conservation and Survey Division, University of Nebraska analysis Citation: Szilagyi, J., Sensitivity analysis of aquifer parameter estimations based on the Laplace

  12. Interpersonal Action Across Organizational Boundaries: Threat and Trust in the Context of Social Network Diversity

    E-Print Network [OSTI]

    Williams, Michele

    2003-03-21T23:59:59.000Z

    This article integrates strategic factors influencing trust with social contextual factors to create a broader understanding of interpersonal trust across organizational boundaries. ...

  13. Microsoft Word - 11-21605_Nuclear_Facility_Boundary_White_Paper...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    those specified for the nuclear - industrial facility boundary. g. Functions from NGNP white paper, INLEXT-10-19509, "Structures, Systems, and Components Safety Classification,"...

  14. The Inner Boundary Condition for a Thin Disk Accreting Into a Black Hole

    E-Print Network [OSTI]

    B. Paczy?ski

    2000-04-10T23:59:59.000Z

    Contrary to some recent claims the `no torque inner boundary condition' as applied at the marginally stable orbit is correct for geometrically thin disks accreting into black holes.

  15. E-Print Network 3.0 - american-caribbean plate boundary Sample...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    American-Caribbean plate boundary, asthenospheric flow... along the margin of northern South America accommodating east-west South American-Caribbean plate motion... - Caribbean...

  16. Modeling of stresses at grain boundaries with respect to occurrence of stress corrosion cracking

    SciTech Connect (OSTI)

    Kozaczek, K.J. [Oak Ridge National Lab., TN (United States); Sinharoy, A.; Ruud, C.O. [Pennsylvania State Univ., University Park, PA (United States); McIlree, A.R. [Electric Power Research Institute, Palo Alto, CA (United States)

    1995-12-31T23:59:59.000Z

    The distributions of elastic stresses/strains in the grain boundary regions were studied by the analytical and the finite element models. The grain boundaries represent the sites where stress concentration occurs as a result of discontinuity of elastic properties across the grain boundary and the presence of second phase particles elastically different from the surrounding matrix grains. A quantitative analysis of those stresses for steels and nickel based alloys showed that the stress concentrations in the grain boundary regions are high enough to cause a local microplastic deformation even when the material is in the macroscopic elastic regime. The stress redistribution as a result of such a plastic deformation was discussed.

  17. Solving fuzzy two-point boundary value problem using fuzzy Laplace transform

    E-Print Network [OSTI]

    Latif Ahmad; Muhammad Farooq; Saif Ullah; Saleem Abdullah

    2014-03-02T23:59:59.000Z

    A natural way to model dynamic systems under uncertainty is to use fuzzy boundary value problems (FBVPs) and related uncertain systems. In this paper we use fuzzy Laplace transform to ?find the solution of two-point boundary value under generalized Hukuhara differentiability. We illustrate the method for the solution of the well known two-point boundary value problem Schrodinger equation, and homogeneous boundary value problem. Consequently, we investigate the solutions of FBVPs under as a new application of fuzzy Laplace transform.

  18. Upper mantle structure beneath the Caribbean-South American plate boundary from surface wave tomography

    E-Print Network [OSTI]

    Niu, Fenglin

    Upper mantle structure beneath the Caribbean-South American plate boundary from surface wave velocity structure of the crust and upper mantle of the Caribbean-South American boundary region American continental lithosphere, the Venezuelan archipelago, and the Caribbean oceanic lithosphere

  19. Spreading of the Free Boundary of an Ideal Fluid in a Vacuum

    E-Print Network [OSTI]

    Bigelow, Stephen

    . For compressible fluids, the normal derivative of the square of the sound speed must be negative liquids (positive fluid density on the free boundary) was established in [12], see also [13], [14. For liquids, the normal derivative of the pressure is negative on the free boundary. This implies

  20. Simulation of Hypersonic Shock Wave/Boundary Layer Interaction Using High Order WENO Scheme

    E-Print Network [OSTI]

    Zha, Gecheng

    Simulation of Hypersonic Shock Wave/Boundary Layer Interaction Using High Order WENO Scheme Yiqing for predicting hypersonic shock wave/boundary layer interaction. The implicit time marching method number of 1.09 Ã? 105 /ft. 1 Introduction Hypersonic aerothermodynamics is one of the most challenging

  1. Study of Emission TurbulenceRadiation Interaction in Hypersonic Boundary Layers

    E-Print Network [OSTI]

    Martín, Pino

    Study of Emission Turbulence­Radiation Interaction in Hypersonic Boundary Layers L. Duan and M. P of emission turbulence­radiation interaction in hypersonic turbulent boundary layers, representative interaction between turbulence and emission at the hypersonic environment under investigation. An explanation

  2. Assessment of TurbulenceChemistry Interaction in Hypersonic Turbulent Boundary Layers

    E-Print Network [OSTI]

    Martín, Pino

    Assessment of Turbulence­Chemistry Interaction in Hypersonic Turbulent Boundary Layers L. Duan of the turbulence­chemistry interaction are performed in hypersonic turbulent boundary layers using direct numerical simulation flowfields under typical hypersonic conditions representative of blunt-body and slender- body

  3. Study of turbulence-chemistry interaction in hypersonic turbulent boundary layers

    E-Print Network [OSTI]

    Martín, Pino

    Study of turbulence-chemistry interaction in hypersonic turbulent boundary layers Lian Duan and M of the turbulence-chemistry interaction (TCI) are performed in hypersonic tur- bulent boundary layers using direct numerical simulation (DNS) flow fields under typical hypersonic conditions representative of blunt

  4. The equilibrium crystal shape of strontium titanate and its relationship to the grain boundary plane distribution

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    The equilibrium crystal shape of strontium titanate and its relationship to the grain boundary system, strontium titanate, is compared with the grain boundary plane dis- tribution (GBPD) as a function of temperature. Strontium titanate has a pronounced surface energy anisotropy and a grain growth anomaly

  5. Modification of boundary lubrication by oil-soluble friction modifier Yingxi Zhua

    E-Print Network [OSTI]

    Granick, Steve

    Modification of boundary lubrication by oil-soluble friction modifier additives Yingxi Zhua in lubricants of the type used at the wet clutch interface in automatic transmissions has been studied using in the boundary lubrication regime and compared to a fully-formulated automatic transmission fluid (ATF). 1

  6. AGU Monograph, Plate Boundary Zones, in press. Page 1 Crustal Block Rotations and Plate Coupling

    E-Print Network [OSTI]

    McCaffrey, Robert

    AGU Monograph, Plate Boundary Zones, in press. Page 1 Crustal Block Rotations and Plate Coupling that considering both block rotations and fault locking significantly improves the fit to the data over models by locking on #12;AGU Monograph, Plate Boundary Zones, in press. Page 2 block-bounding faults and apply

  7. Waves of constant shape and the structure of the \\rotors boundary" in excitable media.

    E-Print Network [OSTI]

    Biktashev, Vadim N.

    wave patterns in R 2 , in terms of the kinematic approach. These patterns include rotating waves by Winfree [13]. The kinematic approach of [8] also considered a boundary of existence of spiral waveWaves of constant shape and the structure of the \\rotors boundary" in excitable media. Yu.E. Elkin

  8. TWO-DIMENSIONAL SIMULATIONS OF VALVELESS PUMPING USING THE IMMERSED BOUNDARY METHOD

    E-Print Network [OSTI]

    Peskin, Charles S.

    TWO-DIMENSIONAL SIMULATIONS OF VALVELESS PUMPING USING THE IMMERSED BOUNDARY METHOD EUNOK JUNG. 1, pp. 19­45 Abstract. Flow driven by pumping without valves is examined, motivated by biomedical words. valveless pumping, immersed boundary method, frequency, CPR AMS subject classifications. 76D05

  9. Comparing calculated and measured grain boundary energies in nickel Gregory S. Rohrer a

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    Laboratories (SNL) [23] have utilized new, high-throughput methods to measure energy for large ensemblesComparing calculated and measured grain boundary energies in nickel Gregory S. Rohrer a , Elizabeth boundary energy data sets for Ni. Using these results, we perform the first large-scale comparison between

  10. Statistical Study of ZigZag Transition Boundaries in Longitudinal Digital Magnetic Recording

    E-Print Network [OSTI]

    Kavcic, Aleksandar

    i Statistical Study of Zig­Zag Transition Boundaries in Longitudinal Digital Magnetic Recording, we study the statistics of zig­zag transition walls in digital magnetic recording­zag boundary itself is a realization of a random process, which is why the observed media noise is indeed noise

  11. Where is the North ChinaSouth China block boundary in eastern China?

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Where is the North China­South China block boundary in eastern China? Michel Faure, Wei Lin of the North China and South China blocks. The eastern extension of the belt (the Sulu area) consists and the lack of ocean-basin rock shows that the boundary between the North China block and South China block

  12. Atomistic simulations of structures and mechanical properties of polycrystalline diamond: Symmetrical S001< tilt grain boundaries

    E-Print Network [OSTI]

    Brenner, Donald W.

    Atomistic simulations of structures and mechanical properties of polycrystalline diamond for diamond to deposit as a polycrystalline film with a high density of grain boundaries and related defects structures and energies of symmetrical 001 tilt grain boundaries GB's in diamond have been calculated over

  13. Measuring the Influence of Grain-Boundary Misorientation on Thermal Groove Geometry in Ceramic Polycrystals

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    Measuring the Influence of Grain-Boundary Misorientation on Thermal Groove Geometry in Ceramic. The width and depth of the thermal grooves formed by these same grain bound- aries were also measured of the grain-boundary misorientation and thermal groove ge- ometry leads to the observation that grain

  14. A gas-solid free boundary problem for compressible viscous gas

    E-Print Network [OSTI]

    and Chemical, Beijing,100029,China Abstract In this paper we propose a gas-solid free boundary problem is physically natural because the density of the gas transited in phase from the solid is usually much less thanA gas-solid free boundary problem for compressible viscous gas Feimin Huang y Akitaka Matsumura y

  15. An advanced 3D boundary element method for characterizations of composite materials

    E-Print Network [OSTI]

    Liu, Yijun

    An advanced 3D boundary element method for characterizations of composite materials X.L. Chena , Y developments in the modeling of composite materials using the boundary element method (BEM) are presented in dealing with nearly-singular integrals, which arise in the BEM modeling of composite materials

  16. Free Vibration Analysis of Kirchoff Plates with Damaged Boundaries by the Chebyshev Collocation Method

    E-Print Network [OSTI]

    Butcher, Eric A.

    Free Vibration Analysis of Kirchoff Plates with Damaged Boundaries by the Chebyshev Collocation for the free vibration analysis of slender Kirchoff plates with both mixed and damaged boundaries an important role in applications of mechanical, aerospace and civil engineering. Studying the free vibration

  17. Friction of a slider on a granular layer: Nonmonotonic thickness dependence and effect of boundary conditions

    E-Print Network [OSTI]

    Kudrolli, Arshad

    Friction of a slider on a granular layer: Nonmonotonic thickness dependence and effect of boundary the effective friction encountered by a mass sliding on a granular layer as a function of bed thickness and boundary roughness conditions. The observed friction has minima for a small number of layers before

  18. A Cartesian grid embedded boundary method for the heat equation and Poissons equation in three dimensions

    E-Print Network [OSTI]

    A Cartesian grid embedded boundary method for the heat equation and Poisson�s equation in three­85] and extends work of McCorquodale, Colella and Johansen [A Cartesian grid embedded boundary method for the heat and time for the heat equation. Cartesian grid methods for elliptic PDE have a long history beginning with the no

  19. A Cartesian grid embedded boundary method for the heat equation on irregular domains

    E-Print Network [OSTI]

    McCorquodale, Peter; Colella, Phillip; Johansen, Hans

    2001-01-01T23:59:59.000Z

    A Cartesian Grid Embedded Boundary Method for the Heatheat equation on irregular time-dependent domains. It is based on the Cartesian gridHEAT EQUATION FOR FIXED BOUNDARIES Spatial discretization The underlying discretization of space is given by rectangular control volumes on a Cartesian grid:

  20. On the moving boundary conditions for a hydraulic fracture Emmanuel Detournay a,b,

    E-Print Network [OSTI]

    Peirce, Anthony

    On the moving boundary conditions for a hydraulic fracture Emmanuel Detournay a,b, , Anthony Peirce 2014 Keywords: Hydraulic fractures Speed equation Ill-posedness a b s t r a c t This paper re-examines the boundary conditions at the moving front of a hydraulic fracture when the fluid front has coalesced

  1. Intercomparison of cloud model simulations of Arctic mixed-phase boundary layer clouds observed during

    E-Print Network [OSTI]

    Zuidema, Paquita

    /crystal concentration also suggests the need for improved understanding of ice nucleation and its parameterizationIntercomparison of cloud model simulations of Arctic mixed-phase boundary layer clouds observed is presented. This case study is based on observations of a persistent mixed-phase boundary layer cloud

  2. Building boundary is necessary for the real estate industry, flood management, and homeland security applications.

    E-Print Network [OSTI]

    Shan, Jie

    Abstract Building boundary is necessary for the real estate industry, flood management, and homeland security applications. The extraction of building boundary is also a crucial and difficult step, and Purdue University campus are evaluated. Introduction Airborne lidar (light detection and ranging

  3. Gas-surface interaction and boundary conditions for the Boltzmann equation

    E-Print Network [OSTI]

    Mieussens, Luc

    Gas-surface interaction and boundary conditions for the Boltzmann equation St´ephane Brull, Pierre Equation. The interaction between the wall atoms and the gas molecules within a thin surface layer of the gas in the bulk flow. Boundary conditions are formally derived from this model by using classical

  4. Relative grain boundary area and energy distributions in nickel Jia Li, Shen J. Dillon 1

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    Relative grain boundary area and energy distributions in nickel Jia Li, Shen J. Dillon 1 , Gregory boundary energies and areas are inversely correlated. Ó 2009 Acta Materialia Inc. Published by Elsevier Ltd and focused ion beam serial sectioning. These data have been used to determine the relative areas of different

  5. Structure and motion of junctions between coherent and incoherent twin boundaries in copper

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    Structure and motion of junctions between coherent and incoherent twin boundaries in copper J online 4 July 2009 Abstract The atomic mechanisms of twin boundary migration in copper under externally. Ã? 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Keywords: Copper

  6. Body Fitted Grid Generation Method with Moving Boundaries and Its Application for analysis of MEMS

    E-Print Network [OSTI]

    Tentzeris, Manos

    Body Fitted Grid Generation Method with Moving Boundaries and Its Application for analysis of MEMS these MEMS devices using body fitted grid generation method with moving boundaries is proposed. This technique is based on the finite-difference time-domain (FD-TD) method and a kind of grid generation

  7. INTERFACES AND BOUNDARIES THE SOLID-SOLID INTERFACE IN THERMAL PHONON RADIATION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    materials as it happens if a metal film deposited on a dielectric crystal is heated and emits thermal pho the thermal boundary resistance predicted by this (>.But no convicting resultsINTERFACES AND BOUNDARIES THE SOLID-SOLID INTERFACE IN THERMAL PHONON RADIATION Institute fiir

  8. Thermal boundary resistance between single-walled carbon nanotubes and surrounding matrices

    E-Print Network [OSTI]

    Maruyama, Shigeo

    Thermal boundary resistance between single-walled carbon nanotubes and surrounding matrices Carl Keywords: carbon nanotube, thermal boundary resistance, molecular dynamics 1 #12;I. INTRODUCTION the thermal conductivity of insulating materials15,16 . The mechanical strength and light weight of polymers

  9. Generalized model of thermal boundary conductance between SWNT and surrounding supercritical Lennard-Jones fluid

    E-Print Network [OSTI]

    Maruyama, Shigeo

    of the promising applications is to use SWNTs as additives to enhance thermal conductivity of composite materials of the composite can be strongly influenced by thermal boundary resistance (TBR) between carbon nanotubes, it is essential to understand TBR. Thermal boundary resistance, with its importance in small scale, has been

  10. PROPAGATION OF ALFVN WAVES AT THE PLASMA SHEET BOUNDARY Robert L. Lysak and Yan Song

    E-Print Network [OSTI]

    Lysak, Bob

    PROPAGATION OF ALFVÃ?N WAVES AT THE PLASMA SHEET BOUNDARY LAYER Robert L. Lysak and Yan Song School conversion or by localized plasma flows in the tail. The generation and propagation of these waves is studied nonlinear MHD simulations of wave propagation at the boundary layer. INTRODUCTION Recent observations from

  11. Boundary conditions for the computation of thermo-acoustic modes in combustion chambers

    E-Print Network [OSTI]

    Boundary conditions for the computation of thermo-acoustic modes in combustion chambers Camilo F LES or Helmholtz solver computations in aeronautical combustion chambers, it is crucial to impose the right boundary conditions at both inlet and outlet of the combustion system. This means providing

  12. Modeling a swimming fish with an initial-boundary value problem: unsteady maneuvers of an elastic

    E-Print Network [OSTI]

    Smith, Marc L.

    Modeling a swimming fish with an initial-boundary value problem: unsteady maneuvers of an elastic In order to model unsteady maneuvers in swimming fish, we develop an initial-boundary value problem for a fourth-order hyperbolic partial differential equation in which the fish's body is treated as an inhomo

  13. THE ONE-DIMENSIONAL SHALLOW WATER EQUATIONS WITH TRANSPARENT BOUNDARY CONDITIONS

    E-Print Network [OSTI]

    Temam, Roger

    THE ONE-DIMENSIONAL SHALLOW WATER EQUATIONS WITH TRANSPARENT BOUNDARY CONDITIONS MADALINA PETCU the question of the local in time well-posedness of the one-dimensional Shallow Water on an interval, these equations being supplemented with suitable boundary conditions. The flows considered are subcritical

  14. Unimodal Maps as Boundary-Restrictions of Two-Dimensional Full-Folding Maps

    E-Print Network [OSTI]

    Tsuiki, Hideki

    Unimodal Maps as Boundary-Restrictions of Two-Dimensional Full-Folding Maps Hideki TSUIKI tsuiki-75-753-6744, Fax:+81-75-753-6694 Abstract It is shown that every unimodal map is realized as a restriction of a simple map defined on the unit disc to a part of its boundary. Our two-dimensional map is called a full

  15. Atomic Di usion from a Material Surface into a Grain Boundary

    E-Print Network [OSTI]

    Bath, University of

    was #12;rst reduced to an eigen- value problem with a 1-d-integro-di#11;erential operator from the surface of a material into a semi-in#12;nite grain boundary orthogonal to the surface in a strip and then to a Riemann-Hilbert boundary- value problem for an open contour that admits solution

  16. Direct injection of ionospheric O sup + into the dayside low latitude boundary layer

    SciTech Connect (OSTI)

    Fuselier, S.A.; Klumpar, D.M.; Peterson, W.K.; Shelley, E.G. (Lockheed Palo Alto Research Laboratory, Palo Alto, California (US))

    1989-10-01T23:59:59.000Z

    Observations from the AMPTE/Charge Composition Explorer (AMPTE/CCE) indicate the presence of two distinct O{sup +} populations in the dayside subsolar low latitude boundary layer during some periods of northward Interplanetary Magnetic Field (IMF). The first population is O{sup +} convected into the boundary layer from the outer magnetosphere and has been reported previously. It is suggested here that the new, second, O{sup +} population is injected into the dayside boundary layer directly from the high latitude ionosphere. This second population can have a significant density and distinct characteristics such as field-aligned flow relative to boundary layer H{sup +} that modify both the plasma composition and dynamics in the low latitude boundary layer. {copyright} American Geophysical Union 1989

  17. A bridging technique to analyze the influence of boundary conditions on instability patterns

    SciTech Connect (OSTI)

    Hu Heng, E-mail: huheng@whu.edu.c [School of Civil Engineering, Wuhan University, 8 South Road of East Lake, 430072 Wuhan (China); Damil, Noureddine, E-mail: noureddine.damil@gmail.co [Laboratoire de Calcul Scientifique en Mecanique, Faculte des Sciences Ben M'Sik, Universite Hassan II Mohammedia-Casablanca, Sidi Othman, Casablanca (Morocco); Potier-Ferry, Michel, E-mail: michel.potierferry@univ-metz.f [Laboratoire d'Etude des Microstructures et de Mecanique des Materiaux, LEM3, UMR CNRS 7239, Universite Paul Verlaine-Metz, Ile du Saulcy, 57045 Metz Cedex 01 (France)

    2011-05-10T23:59:59.000Z

    In this paper, we present a new numerical technique that permits to analyse the effect of boundary conditions on the appearance of instability patterns. Envelope equations of Landau-Ginzburg type are classically used to predict pattern formation, but it is not easy to associate boundary conditions for these macroscopic models. Indeed, envelope equations ignore boundary layers that can be important, for instance in cases where the instability starts first near the boundary. In this work, the full model is considered close to the boundary, an envelope equation in the core and they are bridged by the Arlequin method . Simulation results are presented for the problem of buckling of long beams lying on a non-linear elastic foundation.

  18. Further development and testing of a second-order bulk boundary layer model. Master's thesis

    SciTech Connect (OSTI)

    Krasner, R.D.

    1993-05-03T23:59:59.000Z

    A one-layer bulk boundary layer model is developed. The model predicts the mixed layer values of the potential temperature, mixing ratio, and u- and v-momentum. The model also predicts the depth of the boundary layer and the vertically integrated turbulence kinetic energy (TKE). The TKE is determined using a second-order closure that relates the rate of dissipation to the TKE. The fractional area covered by rising motion sigma and the entrainment rate (E) are diagnostically determined. The model is used to study the clear convective boundary layer (CBL) using data from the Wangara, Australia boundary layer experiment. The Wangara data is also used as an observation base to validate model results. A further study is accomplished by simulating the planetary boundary layer (PBL) over an ocean surface. This study is designed to find the steady-state solutions of the prognostic variable.

  19. Effect of partial recrystallization on the grain size and grain boundary structure of austenitic steel

    SciTech Connect (OSTI)

    Szabo, Peter J., E-mail: szpj@eik.bme.hu

    2012-04-15T23:59:59.000Z

    Cyclic thermomechanical treatment combined with caliber rolling was applied in order to obtain very fine grain structure with high fraction of special grain boundaries in austenitic stainless steel. Partial recrystallization was observed. Recrystallized fraction was assessed from misorientation data measured by electron back scattering diffraction. Due to the partial recrystallization, elastic energy was stored in the deformed parts, and helped grain boundary movement. As a consequence, very fine grained material with high fraction of special boundaries was formed. - Highlights: Black-Right-Pointing-Pointer I combined the advantage of severe plastic deformation and thermomechanical treatment. Black-Right-Pointing-Pointer A very fine grained steel with high fraction of special boundaries was formed. Black-Right-Pointing-Pointer Stored elastic energy hepled the movement of grain boundaries. Black-Right-Pointing-Pointer The amount of recrystallized part was determined by EBSD.

  20. Role of Amorphous Boundary Layer in Enhancing Ionic Conductivity of Lithium–lanthanum–titanate Electrolyte

    SciTech Connect (OSTI)

    Mei, A.; Wang, X.; Lana, J.-L.; Fenga, Y.-C.; Genga, H.-X.; Lina, Y.-H.; Nana, C.-W.

    2010-03-01T23:59:59.000Z

    The low ionic conductivity is a bottleneck of the inorganic solid state electrolyte used for lithium ion battery. In ceramic electrolytes, grain boundary usually dominates the total conductivity. In order to improve the grain boundary effect, an amorphous silica layer is introduced into grain boundary of ceramic electrolytes based on lithium-lanthanum-titanate, as evidenced by electron microscopy. The results showed that the total ionic conductivity could be to be enhanced over 1 x 10{sup -4} S/cm at room temperature. The reasons can be attributed to removing the anisotropy of outer-shell of grains, supplement of lithium ions in various sites in grain boundary and close bindings among grains by the amorphous boundary layer among grains.

  1. Artificial boundary conditions for stationary Navier-Stokes flows past bodies in the half-plane

    E-Print Network [OSTI]

    Boeckle, Christoph

    2012-01-01T23:59:59.000Z

    We discuss artificial boundary conditions for stationary Navier-Stokes flows past bodies in the half-plane, for a range of low Reynolds numbers. When truncating the half-plane to a finite domain for numerical purposes, artificial boundaries appear. We present an explicit Dirichlet condition for the velocity at these boundaries in terms of an asymptotic expansion for the solution to the problem. We show a substantial increase in accuracy of the computed values for drag and lift when compared with results for traditional boundary conditions. We also analyze the qualitative behavior of the solutions in terms of the streamlines of the flow. The new boundary conditions are universal in the sense that they depend on a given body only through one constant, which can be determined in a feed-back loop as part of the solution process.

  2. A unified physical boundary condition for massless fields of arbitrary spin

    E-Print Network [OSTI]

    Adam Stokes; Robert Bennett

    2014-11-04T23:59:59.000Z

    Boundary conditions for the Maxwell and Dirac fields at material surfaces are widely-used and physically well-motivated, but do not appear to have been generalised to deal with higher spin fields. A consequence of this is that calculations of, for example, Casimir forces associated with higher spin fields always select some arbitrary mathematical boundary conditions, rather than those which are physically motivated. Here, we use the two-spinor calculus formalism to present a unified treatment of the boundary conditions routinely employed in the treatment of spin-1/2 and spin-1 fields. We then use this unification to obtain a completely new boundary condition that can be applied to massless fields of any spin, including the spin-2 graviton, and its supersymmetric partner the spin-3/2 gravitino. We demonstrate one important consequence of our generalisation, which is that periodic boundary conditions cannot be applied to any physically-confined fermionic field.

  3. Neumann-Type Boundary Conditions for Hamilton-Jacobi Equations in Smooth Domains

    SciTech Connect (OSTI)

    Day, Martin V. [Department of Mathematics, Virginia Tech, Blacksburg, VA 24061-0123 (United States)], E-mail: day@math.vt.edu

    2006-05-15T23:59:59.000Z

    Neumann or oblique derivative boundary conditions for viscosity solutions of Hamilton-Jacobi equations are considered. As developed by P.L. Lions, such boundary conditions are naturally associated with optimal control problems for which the state equations employ 'Skorokhod' or reflection dynamics to ensure that the state remains in a prescribed set, assumed here to have a smooth boundary. We develop connections between the standard formulation of viscosity boundary conditions and an alternative formulation using a naturally occurring discontinuous Hamiltonian which incorporates the reflection dynamics directly. (This avoids the dependence of such equivalence on existence and uniqueness results, which may not be available in some applications.) At points of differentiability, equivalent conditions for the boundary conditions are given in terms of the Hamiltonian and the geometry of the state trajectories using optimal controls.

  4. Fermionic Casimir Effect on the Topological Insulator Boundary

    E-Print Network [OSTI]

    C. R. Muniz

    2014-12-08T23:59:59.000Z

    In this paper we study the Casimir effect on the conducting surface of a topological insulator characterized by both $Z_2$ topological index and time reversal symmetry, subject to the action of a static and spatially homogeneous magnetic field perpendicular to that surface, at zero temperature. To do this, we consider modifications in the Gauss' law that arise due to the nonzero gradient of the axion-like pseudoscalar factor coupled to the constant magnetic field, which occur in a term that must be added to the electromagnetic Lagrangian in order to account for the topological properties of the system. Such term allows to find an effective point-like charge that changes the quantum vacuum of a spinor field in 1+2 dimensions confined on the edge under analysis. Since that the Casimir energy found depends on a length defined on the boundary, we show that there is a tangential density of force or a shear stress associated to the surface, tending to shrink or stretch it depending on the magnetic field direction. These results are extended for the case in which the surface forms a interface between two TI's.

  5. Grain boundary dissipation in high-{Tc} superconductors

    SciTech Connect (OSTI)

    Gray, K. E.; Miller, D. J.; Field, M. B.; Kim, D. H.; Berghuis, P.

    2000-04-03T23:59:59.000Z

    Thin-film and bulk [001] tilt bicrystal grain boundaries (GBs) in YBa{sub 2}Cu{sub 3}O{sub 7} exhibit a strong dependence of critical current density, J{sub c} on misorientation angle. What was initially difficult to understand was the 30x smaller J{sub c} in bulk GBs which are microscopically more perfect. The authors review an explanation of this zero-field data, which is based on the pinning of Josephson vortices by the meandering found in thin-film GBs. In addition, there is evidence that J{sub c} of GBs does not drop as quickly with applied magnetic field as expected by simple Josephson junction models. The long-wavelength pinning potential due to meandering is less effective at high fields, but Gurevich and Cooley (GC) proposed a new mechanism for an enhanced GB J{sub c} arising from pinned Abrikosov vortices in the banks of a GB which present a static, quasiperiodic pinning potential to pin GB vortices. They find a peak in J{sub c} and an unusual hysteresis which give considerable support to the GC concept. In low fields, the GBs exhibit a larger J{sub c} for field cooling, which is opposite to the usual hysteresis but agrees with GC due to the larger Abrikosov vortex density in the banks. Magnetization data on the same sample are consistent including the identification of the irreversibility field.

  6. SUPERSONIC DOWNFLOWS AT THE UMBRA-PENUMBRA BOUNDARY OF SUNSPOTS

    SciTech Connect (OSTI)

    Louis, Rohan E.; Mathew, Shibu K.; Venkatakrishnan, P. [Udaipur Solar Observatory, Physical Research Laboratory Dewali, Badi Road, Udaipur, Rajasthan-313004 (India); Bellot Rubio, Luis R., E-mail: eugene@prl.res.in [Instituto de Astrofisica de Andalucia (CSIC), Apartado de Correos 3004, 18080 Granada (Spain)

    2011-01-20T23:59:59.000Z

    High-resolution spectropolarimetric observations of three sunspots taken with Hinode demonstrate the existence of supersonic downflows at or close to the umbra-penumbra boundary which have not been reported before. These downflows are confined to large patches, usually encompassing bright penumbral filaments, and have lifetimes of more than 14 hr. The presence of strong downflows in the center-side penumbra near the umbra rules out an association with the Evershed flow. Chromospheric filtergrams acquired close to the time of the spectropolarimetric measurements show large, strong, and long-lived brightenings in the neighborhood of the downflows. The photospheric intensity also exhibits persistent brightenings comparable to the quiet Sun. Interestingly, the orientation of the penumbral filaments at the site of the downflows is similar to that resulting from the reconnection process described by Ryutova et al. The existence of such downflows in the inner penumbra represents a challenge for numerical models of sunspots because they have to explain them in terms of physical processes likely affecting the chromosphere.

  7. No-boundary measure in the regime of eternal inflation

    SciTech Connect (OSTI)

    Hartle, James [Department of Physics, University of California, Santa Barbara, California 93106 (United States); Hawking, S. W. [DAMTP, CMS, Wilberforce Road, CB3 0WA Cambridge (United Kingdom); Hertog, Thomas [APC, UMR 7164 (CNRS, Universite Paris 7), 10 rue A. Domon et L. Duquet, 75205 Paris, France, and International Solvay Institutes, Boulevard du Triomphe, ULB-C.P. 231, 1050 Brussels (Belgium)

    2010-09-15T23:59:59.000Z

    The no-boundary wave function (NBWF) specifies a measure for prediction in cosmology that selects inflationary histories and remains well behaved for spatially large or infinite universes. This paper explores the predictions of the NBWF for linear scalar fluctuations about homogeneous and isotropic backgrounds in models with a single scalar field moving in a quadratic potential. We treat both the spacetime geometry of the universe and the observers inhabiting it quantum mechanically. We evaluate top-down probabilities for local observations that are conditioned on the NBWF and on part of our data as observers of the universe. For models where the most probable histories do not have a regime of eternal inflation, the NBWF predicts homogeneity on large scales, a spectrum of observable fluctuations with a small non-Gaussian component, and a small amount of inflation in our past. By contrast, for models where the dominant histories have a regime of eternal inflation, the NBWF predicts significant inhomogeneity on scales much larger than the present horizon, a Gaussian spectrum of observable fluctuations, and a long period of inflation in our past. The absence or presence of non-Gaussianity in our observable universe therefore provides information about its global structure, assuming the NBWF.

  8. Phonon thermal transport through tilt grain boundaries in strontium titanate

    SciTech Connect (OSTI)

    Zheng, Zexi; Chen, Xiang; Yang, Shengfeng; Xiong, Liming; Chen, Youping [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611 (United States); Deng, Bowen; Chernatynskiy, Aleksandr [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)

    2014-08-21T23:59:59.000Z

    In this work, we perform nonequilibrium molecular dynamics simulations to study phonon scattering at two tilt grain boundaries (GBs) in SrTiO{sub 3}. Mode-wise energy transmission coefficients are obtained based on phonon wave-packet dynamics simulations. The Kapitza conductance is then quantified using a lattice dynamics approach. The obtained results of the Kapitza conductance of both GBs compare well with those obtained by the direct method, except for the temperature dependence. Contrary to common belief, the results of this work show that the optical modes in SrTiO{sub 3} contribute significantly to phonon thermal transport, accounting for over 50% of the Kapitza conductance. To understand the effect of the GB structural disorder on phonon transport, we compare the local phonon density of states of the atoms in the GB region with that in the single crystalline grain region. Our results show that the excess vibrational modes introduced by the structural disorder do not have a significant effect on phonon scattering at the GBs, but the absence of certain modes in the GB region appears to be responsible for phonon reflections at GBs. This work has also demonstrated phonon mode conversion and simultaneous generation of new modes. Some of the new modes have the same frequency as the initial wave packet, while some have the same wave vector but lower frequencies.

  9. Modeling of grain boundary stresses in Alloy 600

    SciTech Connect (OSTI)

    Kozaczek, K.J. [Oak Ridge National Lab., TN (United States); Sinharoy, A.; Ruud, C.O. [Pennsylvania State Univ., University Park, PA (United States); Mcllree, A.R. [Electric Power Research Inst., Palo Alto, CA (United States)

    1995-04-01T23:59:59.000Z

    Corrosive environments combined with high stress levels and susceptible microstructures can cause intergranular stress corrosion cracking (IGSCC) of Alloy 600 components on both primary and secondary sides of pressurized water reactors. One factor affecting the IGSCC is intergranular carbide precipitation controlled by heat treatment of Alloy 600. This study is concerned with analysis of elastic stress fields in vicinity of M{sub 7}C{sub 3} and M{sub 23}C{sub 6} carbides precipitated in the matrix and at a grain boundary triple point. The local stress concentration which can lead to IGSCC initiation was studied using a two-dimensional finite element model. The intergranular precipitates are more effective stress raisers than the intragranular precipitates. The combination of the elastic property mismatch and the precipitate shape can result in a local stress field substantially different than the macroscopic stress. The maximum local stresses in the vicinity of the intergranular precipitate were almost twice as high as the applied stress.

  10. Boundary-Layer Stability and Transition on a Flared Cone in a Mach 6 Quiet Wind Tunnel

    E-Print Network [OSTI]

    Hofferth, Jerrod William

    2013-05-15T23:59:59.000Z

    A key remaining challenge in the design of hypersonic vehicles is the incomplete understanding of the process of boundary-layer transition. Turbulent heating rates are substantially higher than those for a laminar boundary layer, and large...

  11. A Cartesian grid embedded boundary method for solving the Poisson and heat equations with discontinuous coefficients in three dimensions

    E-Print Network [OSTI]

    Crockett, Robert

    2010-01-01T23:59:59.000Z

    A composite grid solver for conjugate heat transfer in ?uid-A Cartesian grid embedded boundary method for the heatA cartesian grid embedded boundary method for the heat

  12. Establishing geochemical constraints on mass accumulation rates across the Cretaceous-Paleogene boundary with extraterrestrial Helium-3

    E-Print Network [OSTI]

    Giron, Marie Minh-Thu

    2013-01-01T23:59:59.000Z

    Records of ocean biogeochemistry in marine sediments show shifts across the Cretaceous-Paleogene boundary (K-Pg) that are simultaneous with the extinction event and onset of the boundary clay deposition. However, the ...

  13. Atom probe study of grain boundary segregation in technically pure molybdenum

    SciTech Connect (OSTI)

    Babinsky, K., E-mail: katharina.babinsky@stud.unileoben.ac.at [Montanuniversität Leoben, Department of Physical Metallurgy and Materials Testing, Franz-Josef Straße 18, 8700 Leoben (Austria); Weidow, J., E-mail: jonathan.weidow@chalmers.se [Chalmers University of Technology, Department of Applied Physics, 412 96 Gothenburg (Sweden); Knabl, W., E-mail: wolfram.knabl@plansee.com [PLANSEE SE, Metallwerk-Plansee-Straße 71, 6600 Reutte (Austria); Lorich, A., E-mail: alexander.lorich@plansee.com [PLANSEE SE, Metallwerk-Plansee-Straße 71, 6600 Reutte (Austria); Leitner, H., E-mail: harald.leitner@bohler-edelstahl.at [Montanuniversität Leoben, Department of Physical Metallurgy and Materials Testing, Franz-Josef Straße 18, 8700 Leoben (Austria); Primig, S., E-mail: sophie.primig@unileoben.ac.at [Montanuniversität Leoben, Department of Physical Metallurgy and Materials Testing, Franz-Josef Straße 18, 8700 Leoben (Austria)

    2014-01-15T23:59:59.000Z

    Molybdenum, a metal with excellent physical, chemical and high-temperature properties, is an interesting material for applications in lighting-technology, high performance electronics, high temperature furnace construction and coating technology. However, its applicability as a structural material is limited because of the poor oxidation resistance at high temperatures and a brittle-to-ductile transition around room temperature, which is influenced by the grain size and the content of interstitial impurities at the grain boundaries. Due to the progress of the powder metallurgical production during the last decades, the amount of impurities in the current quality of molybdenum has become so small that surface sensitive techniques are not applicable anymore. Therefore, the atom probe, which allows the detection of small amounts of impurities as well as their location, seems to be a more suitable technique. However, a site-specific specimen preparation procedure for grain boundaries in refractory metals with a dual focused ion beam/scanning electron microscope is still required. The present investigation describes the development and successful application of such a site-specific preparation technique for grain boundaries in molybdenum, which is significantly improved by a combination with transmission electron microscopy. This complimentary technique helps to improve the visibility of grain boundaries during the last preparation steps and to evidence the presence of grain and subgrain boundaries without segregants in atom probe specimens. Furthermore, in industrially processed and recrystallized molybdenum sheets grain boundary segregation of oxygen, nitrogen and potassium is successfully detected close to segregated regions which are believed to be former sinter pores. - Highlights: • First study of grain boundary segregation in molybdenum by atom probe • Site-specific preparation technique by FIB and TEM successfully developed • Grain boundary segregation of oxygen, nitrogen and potassium found • Segregation in former sinter-pores detected • Presence of grain boundaries without segregation evidenced.

  14. Research of a boundary condition quantifiable correction method in the assembly homogenization

    SciTech Connect (OSTI)

    Peng, L. H.; Liu, Z. H.; Zhao, J. [Inst. of Nuclear and New Energy Technology, Tsinghua Univ., Beijing, 100084 (China); Li, W. H. [China Nuclear Power Technology Research Inst., Shenzhen, 518026 (China)

    2012-07-01T23:59:59.000Z

    The methods and codes currently used in assembly homogenization calculation mostly adopt the reflection boundary conditions. The influences of real boundary conditions on the assembly homogenized parameters were analyzed. They were summarized into four quantifiable effects, and then the mathematical expressions could be got by linearization hypothesis. Through the calculation of a test model, it had been found that the result was close to transport calculation result when considering four boundary quantifiable effects. This method would greatly improve the precision of a core design code which using the assembly homogenization methods, but without much increase of the computing time. (authors)

  15. Grain boundary enhanced carrier collection in CdTe solar cells

    SciTech Connect (OSTI)

    Li, Chen [ORNL] [ORNL; Wu, Yelong [University of Toledo] [University of Toledo; Poplawsky, Jonathan D [ORNL] [ORNL; Paudel, Naba [University of Toledo] [University of Toledo; Yin, Wanjian [University of Toledo] [University of Toledo; Pennycook, Timothy [University of Oxford] [University of Oxford; Haigh, Sarah [University of Manchester, UK] [University of Manchester, UK; Oxley, Mark P [ORNL] [ORNL; Lupini, Andrew R [ORNL] [ORNL; Al-jassim, Mowafak [National Renewable Energy Laboratory (NREL)] [National Renewable Energy Laboratory (NREL); Pennycook, Stephen J [ORNL] [ORNL; Yan, Yanfa [University of Toledo] [University of Toledo

    2014-01-01T23:59:59.000Z

    The atomic structure and composition of grain boundaries in CdCl2 treated CdTe solar cells have been determined with aberration-corrected scanning transmission electron microscopy and electron energy loss spectroscopy. A high fraction of Te in the grain boundary regions has been substituted by Cl. Density functional calculations reveal the origin of such segregation levels, and further indicate the GBs are likely inverted to n-type, establishing local P-N junctions, which help to separate electron-hole carriers. The results are in good agreement with electron beam induced current observations of high collection efficiency at grain boundaries.

  16. Ion boundary conditions in semi-infinite fluid models of electron beam-plasma interaction

    SciTech Connect (OSTI)

    Levko, Dmitry [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Universite de Toulouse, UPS, INPT Toulouse, 118 route de Narbonne, F-31062 Toulouse cedex 9 (France)

    2014-10-15T23:59:59.000Z

    The modified Bohm criterion is derived for the plasma consisting of the monoenergetic electron beam and thermal electrons. This criterion allows us to define the accurate ion boundary conditions for semi-infinite collisionless fluid models of electron beam–plasma interaction. In the absence of electron beam, these boundary conditions give the classical sheath parameters. When the monoenergetic electron beam propagates through the plasma, the fluid model with proposed boundary conditions gives the results, which are in qualitative agreement with the results obtained earlier in M. Sharifian and B. Shokri, Phys. Plasmas 14, 093503 (2007). However, dynamics and parameters of the plasma sheath are different.

  17. Three lectures on global boundary conditions and the theory of self--adjoint extensions of the covariant Laplace--Beltrami and Dirac operators on Riemannian manifolds with boundary

    E-Print Network [OSTI]

    A. Ibort

    2012-05-16T23:59:59.000Z

    In these three lectures we will discuss some fundamental aspects of the theory of self-adjoint extensions of the covariant Laplace-Beltrami and Dirac operators on compact Riemannian manifolds with smooth boundary emphasizing the relation with the theory of global boundary conditions. Self-adjoint extensions of symmetric operators, specially of the Laplace-Beltrami and Dirac operators, are fundamental in Quantum Physics as they determine either the energy of quantum systems and/or their unitary evolution. The well-known von Neumann's theory of self-adjoint extensions of symmetric operators is not always easily applicable to differential operators, while the description of extensions in terms of boundary conditions constitutes a more natural approach. Thus an effort is done in offering a description of self-adjoint extensions in terms of global boundary conditions showing how an important family of self-adjoint extensions for the Laplace-Beltrami and Dirac operators are easily describable in this way. Moreover boundary conditions play in most cases an significant physical role and give rise to important physical phenomena like the Casimir effect. The geometrical and topological structure of the space of global boundary conditions determining regular self-adjoint extensions for these fundamental differential operators is described. It is shown that there is a natural homology class dual of the Maslov class of the space. A new feature of the theory that is succinctly presented here is the relation between topology change on the system and the topology of the space of self-adjoint extensions of its Hamiltonian. Some examples will be commented and the one-dimensional case will be thoroughly discussed.

  18. Characterizing the Separation and Reattachment of Suction Surface Boundary Layer in Low Pressure Turbine Using Massively Parallel Large Eddy Simulations

    E-Print Network [OSTI]

    Jagannathan, Shriram

    2012-02-14T23:59:59.000Z

    cient, p p1 1 2 U21 Cax Axial chord H12 Form factor R11 Correlation coe cient Tu Turbulence intensity Ue Boundary layer edge velocity U1 Freestream velocity 1 Displacement thickness of a boundary layer 2 Momentum thickness of a boundary...

  19. At Journalism's Boundaries: A Reporter's Journey from Fact to the Emotion of Truth

    E-Print Network [OSTI]

    Loesser, Ernest

    2012-10-19T23:59:59.000Z

    This thesis is a work of literary journalism that explores the distinct boundaries in style that partition how a writer reports objective facts and reveals subjective experience. In brief, it is a genre-breaking prose composition that weds objective...

  20. Topological insulator and the theta vacuum in a system without boundaries

    E-Print Network [OSTI]

    Chen, Kuang-Ting

    In this paper we address two questions concerning the effective action of a topological insulator in one- and three-dimensional space without boundaries, such as a torus. The first is whether a uniform theta term with ...

  1. On the pointwise jump condition at the free boundary in the 1-phase ...

    E-Print Network [OSTI]

    2004-02-09T23:59:59.000Z

    Our paper is close in scope to [We2], where the author studies the structure of the free boundary in the space variables for a.e. level of t. He does this instead by ...

  2. On the Configuration of the US Western Interconnection Voltage Stability Boundary

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Vyakaranam, Bharat; Wu, Di; Hou, Zhangshuan; Elbert, Stephen T.; Huang, Zhenyu

    2014-04-01T23:59:59.000Z

    Abstract—Stability limits are considered in power system planning and operations to estimate the available stability margins and, if possible, to maximize the utilization of transmission facilities. These important tasks are influenced by configuration of the stability boundary. The paper introduces a new fast approach to explore the voltage stability boundary of a large system and reveal its detailed multidimensional structure. The 17939-bus U.S. Western Interconnection planning model was used to illustrate the method. Significant peculiarities of the boundary’s configuration were identified, including its nonconvexity, discontinuity, branching and internal singularities (“holes”) that were not known before and could not been found by traditional methods. Experiments using WECC system are performed to evaluate the computation time using different methods. Our results show that the proposed methods are very promising in reducing calculation time and complexity

  3. Biogeochemical proxies for environmental and biotic conditions at the Permian-Triassic boundary

    E-Print Network [OSTI]

    Hays, Lindsay Elizabeth

    2010-01-01T23:59:59.000Z

    The extinction at the Permian-Triassic boundary marked one of the most profound events of the Phanerozoic Eon. Although numerous hypotheses have been proposed, the trigger mechanism continues to be debated. This thesis ...

  4. Experimental visualization of the near-boundary hydrodynamics about fish-like swimming bodies

    E-Print Network [OSTI]

    Techet, Alexandra Hughes

    2001-01-01T23:59:59.000Z

    This thesis takes a look at the near boundary flow about fish-like swimming bodies. Experiments were performed up to Reynolds number 106 using laser Doppler velocimetry and particle imaging techniques. The turbulence in ...

  5. Stability Analysis for a Saline Boundary Layer Formed by Uniform Up ow Using Finite Elements

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    density in the deeper underground and high salt water density at the boundary layer), gravitation plays and Darcy's law. In this report we #12;rst give an overview of semi-analytical methods to analyse

  6. The Effects of Step Excrescences on Swept-Wing Boundary-Layer Transition

    E-Print Network [OSTI]

    Duncan, Jr., Glen T.

    2014-08-12T23:59:59.000Z

    flutter and handling-quality clearance flight proved the new test article is safe for the flight-testing experiments. Pressure measurements are compared with computational results, infrared thermography is used to globally detect boundary...

  7. Efficient numerical methods for capacitance extraction based on boundary element method

    E-Print Network [OSTI]

    Yan, Shu

    2006-04-12T23:59:59.000Z

    algorithms based on boundary element methods (BEM) and to compute the capacitance extraction in the presence of floating dummy conductors. We propose the PHiCap algorithm, which is based on a hierarchical refinement algorithm and the wavelet transform. Unlike...

  8. Nonlinear equilibration of baroclinic eddies : the role of boundary layer processes and seasonal forcing

    E-Print Network [OSTI]

    Zhang, Yang, Ph. D. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    In this thesis, the influence of boundary layer processes and seasonal forcing on baroclinic eddy equilibration is studied to understand how the baroclinic adjustment is modified when taking into account these two factors. ...

  9. Observations of Turbulence in the Ocean Surface Boundary Layer: Energetics and Transport

    E-Print Network [OSTI]

    Gerbi, Gregory P.

    Observations of turbulent kinetic energy (TKE) dynamics in the ocean surface boundary layer are presented here and compared with results from previous observational, numerical, and analytic studies. As in previous studies, ...

  10. VARIATIONS IN THE HELIOSPHERIC POLAR ENERGETIC NEUTRAL ATOM FLUX OBSERVED BY THE INTERSTELLAR BOUNDARY EXPLORER

    E-Print Network [OSTI]

    Reisenfeld, D. B.

    The ecliptic poles are observed continuously by the Interstellar Boundary Explorer (IBEX); thus, it is possible to discern temporal variations in the energetic neutral atoms (ENAs) from the outer heliosphere on timescales ...

  11. Intelligence and Behavioral Boundaries Scott A. Wallace and John E. Laird

    E-Print Network [OSTI]

    Wallace, Scott

    Intelligence and Behavioral Boundaries Scott A. Wallace and John E. Laird Arti#12;cial Intelligence INTRODUCTION In his 1990 book, Uni#12;ed Theories of Cognition (UTC) [6], Newell observes that notions

  12. Evaluation of Wall Boundary Condition Parameters for Gas-Solids Fluidized Bed Simulations

    SciTech Connect (OSTI)

    Li, Tingwen; Benyahia, Sofiane

    2013-10-01T23:59:59.000Z

    Wall boundary conditions for the solids phase have significant effects on numerical predictions of various gas-solids fluidized beds. Several models for the granular flow wall boundary condition are available in the open literature for numerical modeling of gas-solids flow. In this study, a model for specularity coefficient used in Johnson and Jackson boundary conditions by Li and Benyahia (AIChE Journal, 2012, 58, 2058-2068) is implemented in the open-source CFD code-MFIX. The variable specularity coefficient model provides a physical way to calculate the specularity coefficient needed by the partial-slip boundary conditions for the solids phase. Through a series of 2-D numerical simulations of bubbling fluidized bed and circulating fluidized bed riser, the model predicts qualitatively consistent trends to the previous studies. Furthermore, a quantitative comparison is conducted between numerical results of variable and constant specularity coefficients to investigate the effect of spatial and temporal variations in specularity coefficient.

  13. Modeling stress accelerated grain boundary oxidation (SAGBO) in INCOLOY alloy 908

    E-Print Network [OSTI]

    Soontrapa, Chaiyod

    2005-01-01T23:59:59.000Z

    This study explores the possibility of extending the Ph.D. work of Yan Xu on copper-tin alloys (University of Pennsylvania, 1999) to model stress accelerated grain boundary oxidation (SAGBO) in INCOLOY alloy 908. The steady ...

  14. Wavelet analysis study of microbubble drag reduction in a boundary channel flow

    E-Print Network [OSTI]

    Zhen, Ling

    2006-04-12T23:59:59.000Z

    Particle Image Velocimetry (PIV) and pressure measurement techniques were performed to investigate the drag reduction due to microbubble injection in the boundary layer of a fully developed turbulent channel flow. Two-dimensional full-field velocity...

  15. Dynamics on the Laminar-Turbulent Boundary and the Origin of the Maximum Drag Reduction Asymptote

    E-Print Network [OSTI]

    Graham, Michael D.

    Dynamical trajectories on the boundary in state space between laminar and turbulent plane channel flow—edge states—are computed for Newtonian and viscoelastic fluids. Viscoelasticity has a negligible effect on the properties ...

  16. An energy absorbing far-field boundary condition for the elastic wave equation

    SciTech Connect (OSTI)

    Petersson, N A; Sjogreen, B

    2008-07-15T23:59:59.000Z

    The authors present an energy absorbing non-reflecting boundary condition of Clayton-Engquist type for the elastic wave equation together with a discretization which is stable for any ratio of compressional to shear wave speed. They prove stability for a second order accurate finite-difference discretization of the elastic wave equation in three space dimensions together with a discretization of the proposed non-reflecting boundary condition. The stability proof is based on a discrete energy estimate and is valid for heterogeneous materials. The proof includes all six boundaries of the computational domain where special discretizations are needed at the edges and corners. The stability proof holds also when a free surface boundary condition is imposed on some sides of the computational domain.

  17. Solution of the Kramers' problem about isothermal sliding of moderately dense gas with accomodation boundary conditions

    E-Print Network [OSTI]

    A. V. Latyshev; A. D. Kurilov

    2014-12-30T23:59:59.000Z

    Half-space boundary Kramers' problem about isothermal sliding of moderate dense gas with accomodation boundary conditions along a flat firm surface is solving. The new method of the solution of boundary problems of the kinetic theory is applied (see JVMMF, 2012, 52:3, 539-552). The method allows to receive the solution with arbitrary degree of accuracy. The idea of representation of boundary condition on distribution function in the form of source in the kinetic equation serves as the basis for the method mentioned above. By means of Fourier integrals the kinetic equation with a source comes to the Fredholm integral equation of the second kind. The solution has been received in the form of Neumann's number.

  18. Advances in the visualization and analysis of boundary layer flow in swimming fish

    E-Print Network [OSTI]

    Anderson, Erik J

    2005-01-01T23:59:59.000Z

    In biology, the importance of fluid drag, diffusion, and heat transfer both internally and externally, suggest the boundary layer as an important subject of investigation, however, the complexities of biological systems ...

  19. Design of a model propulsor for a boundary layer ingesting aircraft

    E-Print Network [OSTI]

    Grasch, Adam D. (Adam Davis)

    2013-01-01T23:59:59.000Z

    This thesis presents contributions to the analysis and design of propulsion simulators for 1:11 and 1:4 scale model wind tunnel investigations of an advanced civil transport aircraft with boundary layer ingestion (BLI). ...

  20. Boundaries to membranes : the urban project revisited : an urban strategy for Rio de Janeiro, Zona Norte

    E-Print Network [OSTI]

    Dudek, Phebe (Phebe Helena Melania)

    2014-01-01T23:59:59.000Z

    This thesis investigates urban boundaries in the North Zone of Rio de Janeiro. The Zona Norte transitioned in the last hundred years from a rural outskirts area of Rio, into its industrial hinterland, into a fully urbanized ...

  1. Boundary element simulation of oscillating foil with leading-edge separation

    E-Print Network [OSTI]

    Dong, Xiaoxia, S.M. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    In this thesis, we develop a numerical model to account for the leading-edge separation for the boundary element simulation of the oscillating foil with potential flow assumption. Similar to the trailing-edge separation, ...

  2. Turbulent combined wave-current boundary layer model for application in coastal waters

    E-Print Network [OSTI]

    Humbyrd, Chelsea Joy

    2012-01-01T23:59:59.000Z

    Accurately predicting transport processes, including sediment transport, in the coastal environment is impossible without correct current velocity and shear stress information. A combined wave-current boundary layer theory ...

  3. Observations of turbulent fluxes and turbulence dynamics in the ocean surface boundary layer

    E-Print Network [OSTI]

    Gerbi, Gregory Peter

    2008-01-01T23:59:59.000Z

    This study presents observations of turbulence dynamics made during the low winds portion of the Coupled Boundary Layers and Air-Sea Transfer experiment (CBLAST-Low). Observations were made of turbulent fluxes, turbulent ...

  4. Deformation behavior of cylindrical block copolymer bicrystals : pathway to understanding block copolymer grain boundaries

    E-Print Network [OSTI]

    Wanakamol, Panitarn

    2006-01-01T23:59:59.000Z

    Model bicrystals made by adhering pieces of near-single-crystal styrene-isoprene-styrene (SIS) cylindrical block copolymer (BCP), produced by a roll-casting process; yield various types of pure tilt grain boundaries. The ...

  5. The effect of periodic-unsteady wakes, curvature, and pressure gradient on boundary-layer transition

    E-Print Network [OSTI]

    Radke, Robert Edward

    1994-01-01T23:59:59.000Z

    Boundary-layer transition on a concave curved plate has been investigated with and without periodic-unsteady inlet flow at zero and negative pressure gradients. The periodicunsteady wakes were created using a rotating squirrel-cage type wake...

  6. Seismic and gravitational studies of melting in the mantle's thermal boundary layers

    E-Print Network [OSTI]

    Van Ark, Emily M

    2007-01-01T23:59:59.000Z

    This thesis presents three studies which apply geophysical tools to the task of better understanding mantle melting phenomena at the upper and lower boundaries of the mantle. The first study uses seafloor bathymetry and ...

  7. Detecting subject boundaries within text: A language-independent statistical approach. 

    E-Print Network [OSTI]

    Richmond, Korin; Smith, Andrew James; Amitay, Einat

    1997-01-01T23:59:59.000Z

    We describe here an algorithm for detecting subject boundaries within text based on a statistical lexical similarity measure. Hearst has already tackled this problem with good results (Hearst, 1994). One of her main ...

  8. E-Print Network 3.0 - antiphase domain boundaries Sample Search...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Ecology 5 Long period structures in Ti1+xAl3-x alloys : experimental evidence of a devil's staircase ? Summary: of the domains (limited by the antiphase boundaries)...

  9. Week 11 Notes, Math 8610, Tanveer 1. 2-D inviscid irrotional free boundary: Conformal

    E-Print Network [OSTI]

    Tanveer, Saleh

    in the absence of a body force, but in the presence of surface tension. Note that 2-D water waves may write it as g ImZ. We now derive the kinematic boundary condition. Since the free boundary is given)] = tZ + dZ d t Hence from (1.12), we obtain the kinematic condition to be equivalent to (1.14) Re - t

  10. Shipboard measurements of the cloud-capped marine boundary layer during FIRE/ASTEX

    SciTech Connect (OSTI)

    NONE

    1997-09-01T23:59:59.000Z

    Results are reported on measurements of the cloud-capped marine boundary layer during FIRE/ASTEX. A method was developed from the ASTEX dataset for measuring profiles of liquid water content, droplet size and concentration from cloud radar/microwave radiometer data in marine boundary layer clouds. Profiles were also determined from the first three moments of the Doppler spectrum measured in drizzle with the ETL cloud radar during ASTEX.

  11. Effect of a surface boundary layer on an intensifying, downward-propagating vortex

    E-Print Network [OSTI]

    Wood, Vincent Tunstall

    2012-06-07T23:59:59.000Z

    EFFECT OF A SURFACE BOUNDARY LAYER ON AN INTENSIFYING, DOWNWARD-PROPAGATING VORTEX A Thesis by VINCENT TUNSTALL WOOD Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1977 Major Subject: Meteorology EFFECT OF A SURFACE BOUNDARY LAYER ON AN INTENSIFYING, DOWNWARD-PROPAGATING VORTEX A Thesis by VINCENT TUNSTALL WOOD Approved as to style and content by: (Chairman of Committee) (Head of Department...

  12. Boundary Effects on Bose-Einstein Condensation in Ultra-Static Space-Times

    E-Print Network [OSTI]

    L. Akant; E. Ertugrul; Y. Gul; O. T. Turgut

    2014-07-08T23:59:59.000Z

    The boundary effects on the Bose-Einstein condensation of an ideal Bose gas on an ultra-static space-time are studied by a Mellin-Barnes type asymptotic analysis of the harmonic sum representing the depletion coefficient. Small $\\beta m$ regime, which is the relevant regime for the relativistic gas, is studied through the heat kernel expansion for both Dirichlet and Neumann boundary conditions. The analysis is made for both charged bosons and neutral bosons.

  13. Boundary Effects on Bose-Einstein Condensation in Ultra-Static Space-Times

    E-Print Network [OSTI]

    Akant, L; Gul, Y; Turgut, O T

    2015-01-01T23:59:59.000Z

    The boundary effects on the Bose-Einstein condensation of an ideal Bose gas on an ultra-static space-time are studied by a Mellin-Barnes type asymptotic analysis of the harmonic sum representing the depletion coefficient. Small $\\beta m$ regime, which is the relevant regime for the relativistic gas, is studied through the heat kernel expansion for both Dirichlet and Neumann boundary conditions. The analysis is made for both charged bosons and neutral bosons.

  14. Conformal invariance of crossing probabilities for the Ising model with free boundary conditions

    E-Print Network [OSTI]

    Stéphane Benoist; Hugo Duminil-Copin; Clément Hongler

    2014-10-14T23:59:59.000Z

    We prove that crossing probabilities for the critical planar Ising model with free boundary conditions are conformally invariant in the scaling limit, a phenomenon first investigated numerically by Langlands, Lewis and Saint-Aubin. We do so by establishing the convergence of certain exploration processes towards SLE$(3,\\frac{-3}2,\\frac{-3}2)$. We also construct an exploration tree for free boundary conditions, analogous to the one introduced by Sheffield.

  15. Influence of surface heating on the boundary layer stability of flows with favorable pressure gradients

    E-Print Network [OSTI]

    Landrum, David Brian

    2012-06-07T23:59:59.000Z

    INFLUENCE OF SURFACE HEATING ON THE BOUNDARY LAYER STABILITY OF FLOWS WITH FAVORABI E PRESSURE GRADIENTS A Thesis by DAVID BRIAN LANDRUM Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1986 Major Subject: Aerospace Engineering INFLUENCE OF SURFACE HEATING ON THE BOUNDARY LAYER STABILITY OF FLOWS WITH FAVORABLE PRESSURE GRADIENTS A Thesis by DAVID BRIAN LANDRUM Approved as to style and content...

  16. Anti-FFBRST Transformations for the BLG Theory in Presence of a Boundary

    E-Print Network [OSTI]

    Faizal, Mir; Mandal, Bhabani P

    2015-01-01T23:59:59.000Z

    In this paper we will analyse the anti-BRST symmetries of Bagger-Lambert-Gustavsson (BLG) theory in presence of a boundary. We will analyses these symmetries in both linear and non-linear gauges. We will also derive the finite field version of the anti-BRST transformations for the BLG theory in presence of a boundary. These finite field transformations will be used to relate generating functional in linear gauge to the generating functional in the non-linear gauge.

  17. Observation of thermally etched grain boundaries with the FIB/TEM technique

    SciTech Connect (OSTI)

    Palizdar, Y., E-mail: y.palizdar@merc.ac.ir [Nanotechnology and advanced materials department, Materials and energy research centre (MERC), Karaj (Iran, Islamic Republic of); San Martin, D. [MATERALIA group, Department of Physical Metallurgy, (CENIM-CSIC), Centro Nacional de Investigaciones Metalúrgicas Av. Gregorio del Amo 8, 28040 Madrid (Spain); Ward, M.; Cochrane, R.C.; Brydson, R.; Scott, A.J. [Institute for Materials Research, SPEME, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2013-10-15T23:59:59.000Z

    Thermal etching is a method which is able to reveal and characterize grain boundaries, twins or dislocation structures and determine parameters such as grain boundary energies, surface diffusivities or study phase transformations in steels, intermetallics or ceramic materials. This method relies on the preferential transfer of matter away from grain boundaries on a polished sample during heating at high temperatures in an inert/vacuum atmosphere. The evaporation/diffusion of atoms at high temperatures results in the formation of grooves at the intersections of the planes of grain/twin boundaries with the polished surface. This work describes how the combined use of Focussed Ion Beam and Transmission Electron Microscopy can be used to characterize not only the grooves and their profile with the surface, but also the grain boundary line below the groove, this method being complementary to the commonly used scanning probe techniques. - Highlights: • Thermally etched low-carbon steel samples have been characterized by FIB/TEM • Grain boundary (GB) lines below the groove have been characterized in this way • Absence of ghost traces and large ? angle suggests that GB are not stationary but mobile • Observations correlate well with previous works and Mullins' investigations [22].

  18. Binding of He{sub n}V clusters to ?-Fe grain boundaries

    SciTech Connect (OSTI)

    Tschopp, M. A., E-mail: mark.a.tschopp.civ@mail.mil [U.S. Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005 (United States); Gao, F. [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Solanki, K. N. [Arizona State University, Tempe, Arizona 85287 (United States)

    2014-06-21T23:59:59.000Z

    The objective of this research is to explore the formation/binding energetics and length scales associated with the interaction between He{sub n}V clusters and grain boundaries in bcc ?-Fe. In this work, we calculated formation/binding energies for 1–8 He atoms in a monovacancy at all potential grain boundary (GB) sites within 15?Å of the ten grain boundaries selected (122106 simulations total). The present results provide detailed information about the interaction energies and length scales of 1–8 He atoms with grain boundaries for the structures examined. A number of interesting new findings emerge from the present study. First, the ?3(112) “twin” GB has significantly lower binding energies for all He{sub n}V clusters than all other boundaries in this study. For all grain boundary sites, the effect of the local environment surrounding each site on the He{sub n}V formation and binding energies decreases with an increasing number of He atoms in the He{sub n}V cluster. Based on the calculated dataset, we formulated a model to capture the evolution of the formation and binding energy of He{sub n}V clusters as a function of distance from the GB center, utilizing only constants related to the maximum binding energy and the length scale.

  19. Spatially Resolved Mapping of Electrical Conductivity around Individual Domain (Grain) Boundaries in Graphene

    SciTech Connect (OSTI)

    Li, An-Ping [ORNL; Clark, Kendal W [ORNL; Zhang, Xiaoguang [ORNL; Vlassiouk, Ivan V [ORNL; He, Guowei [Carnegie Mellon University (CMU); Feenstra, Randall [Carnegie Mellon University (CMU)

    2013-01-01T23:59:59.000Z

    Graphene films can now be produced on the scale of up to meters. However, all large-scale graphene films contain topological defects that can significantly affect the characteristic transport behaviors of graphene. Here, we spatially map the structures and electronic transport near specific domain and grain boundaries in graphene, and evaluate effects of different types of defect on the electronic conductivity in epitaxial graphene grown on SiC and CVD graphene on Cu subsequently transferred to a SiO2 substrate. We use a combined approach with a multi-probe scanning tunneling potentiometry to investigate both structures and transport at individual grain boundaries and domain boundaries that are defined by coalesced grains, surface steps, and changes in layer thickness. It is found that the substrate step on SiC presents a significant potential barrier for electron transport of epitaxial graphene due to the reduced charge transport from the substrate at the step edges, monolayer-bilayer boundaries exhibit a high resistivity that can change depending on directions of the current across the boundary, and the resistivity of grain boundaries changes with the transition width of the disordered region between two adjacent grains in graphene. The detailed understanding of graphene defects will provide the feedback for controlled engineering of defects in large-scale graphene films.

  20. On the Relation of KS Entropy and Permutation Entropy

    E-Print Network [OSTI]

    Karsten Keller; Anton M. Unakafov; Valentina A. Unakafova

    2014-07-24T23:59:59.000Z

    Since Bandt et al. have shown that the permutation entropy and the Kolmogorov-Sinai entropy coincide for piecewise monotone interval maps, the relationship of both entropies for time-discrete dynamical systems is of a certain interest. The aim of this paper is a discussion of this relationship on the basis of an ordinal characterization of the Kolmogorov-Sinai entropy recently given.

  1. Quasilocal conservation laws in XXZ spin-1/2 chains: open, periodic and twisted boundary conditions

    E-Print Network [OSTI]

    Tomaz Prosen

    2014-08-05T23:59:59.000Z

    A continuous family of quasilocal exact conservation laws is constructed in the anisotropic Heisenberg (XXZ) spin-1/2 chain for periodic (or twisted) boundary conditions and for a set of commensurate anisotropies densely covering the entire easy plane interaction regime. All local conserved operators follow from the standard (Hermitian) transfer operator in fundamental representation (with auxiliary spin s=1/2), and are all even with respect to a spin flip operation. However, the quasilocal family is generated by differentiation of a non-Hermitian highest weight transfer operator with respect to a complex auxiliary spin representation parameter s and includes also operators of odd parity. For a finite chain with open boundaries the time derivatives of quasilocal operators are not strictly vanishing but result in operators localized near the boundaries of the chain. We show that a simple modification of the non-Hermitian transfer operator results in exactly conserved, but still quasilocal operators for periodic or generally twisted boundary conditions. As an application, we demonstrate that implementing the new exactly conserved operator family for estimating the high-temperature spin Drude weight results, in the thermodynamic limit, in exactly the same lower bound as for almost conserved family and open boundaries. Under the assumption that the bound is saturating (suggested by agreement with previous thermodynamic Bethe ansatz calculations) we propose a simple explicit construction of infinite time averages of local operators such as the spin current.

  2. Effect of Grain Boundaries on Krypton Segregation Behavior in Irradiated Uranium Dioxide

    SciTech Connect (OSTI)

    Billy Valderrama; Lingfeng He; Hunter B. Henderson; Janne Pakarinen; Brian Jaques; Jian Gan; Darryl P. Butt; Todd R. Allen; Michele V. Manuel

    2015-01-01T23:59:59.000Z

    Fission products, such as krypton (Kr), are known to be insoluble within UO2, segregating towards grain boundaries, eventually leading to a lowering of the thermal conductivity and fuel swelling. Recent computational studies have identified that differences in grain boundary structure have a significant effect on the segregation behavior of fission products. However, experimental work supporting these simulations is lacking. Atom probe tomography was used to measure the Kr distribution across grain boundaries in UO2. Polycrystalline depleted-UO2 samples was irradiated with 0.7 and 1.8 MeV Kr-ions and annealed to 1000, 1300, and 1600°C for 1 hour to produce a Kr-bubble dominated microstructure. The results of this work indicate a strong dependence of Kr concentration as a function of grain boundary structure. Temperature also influences grain boundary chemistry with greater Kr concentration evident at higher temperatures, resulting in a reduced Kr concentration in the bulk. While Kr migration is active at elevated temperatures, no changes in grain size or texture were observed in the irradiated samples.

  3. Turbulent heat transfer in parallel flow boundary layers with streamwise step changes in surface conditions

    SciTech Connect (OSTI)

    Lindberg, W.R.; Lee, R.C.; Smathers, L.B. (Univ. of Wyoming, Laramie (United States))

    1989-11-01T23:59:59.000Z

    This paper examines the convective heat/mass transfer behavior of a turbulent boundary layer with parallel streamlines. The most notable example of such flow is an atmospheric boundary layer with a steady mean wind in the absence of topography. The classic, two-dimensional problem involves the surface boundary condition of a finite-length step change in temperature/concentration in the streamwise direction of an atmospheric flow. In the literature on geophysical evapotranspiration, this problem is known as Sutton's problem (cf. Sutton, 1934, and Brutsaert, 1984). This flow situation is equally applicable to heat/mass transfer in solar ponds, ground solar collectors, and heated roadways, as examples. The present note revisits the Sutton problem, with the can Driest eddy diffusivity model, and expands the types of boundary conditions that are examined to include surface changes in temperature/concentration and fluxes. The parallel streamline condition allows for Graetz-type solutions, with boundary conditions at the surface and in the far flow field. The predicted results are presented as a series of power law correlations of the relevant nondimensional parameters.

  4. Symmetrized Perturbation Determinants and Applications to Boundary Data Maps and Krein-Type Resolvent Formulas

    E-Print Network [OSTI]

    Gesztesy, Fritz

    2010-01-01T23:59:59.000Z

    The aim of this paper is twofold: On one hand we discuss an abstract approach to symmetrized Fredholm perturbation determinants and an associated trace formula for a pair of operators of positive-type, extending a classical trace formula. On the other hand, we continue a recent systematic study of boundary data maps, that is, 2 \\times 2 matrix-valued Dirichlet-to-Neumann and more generally, Robin-to-Robin maps, associated with one-dimensional Schr\\"odinger operators on a compact interval [0,R] with separated boundary conditions at 0 and R. One of the principal new results in this paper reduces an appropriately symmetrized (Fredholm) perturbation determinant to the 2\\times 2 determinant of the underlying boundary data map. In addition, as a concrete application of the abstract approach in the first part of this paper, we establish the trace formula for resolvent differences of self-adjoint Schr\\"odinger operators corresponding to different (separated) boundary conditions in terms of boundary data maps.

  5. Symmetrized Perturbation Determinants and Applications to Boundary Data Maps and Krein-Type Resolvent Formulas

    E-Print Network [OSTI]

    Fritz Gesztesy; Maxim Zinchenko

    2010-07-27T23:59:59.000Z

    The aim of this paper is twofold: On one hand we discuss an abstract approach to symmetrized Fredholm perturbation determinants and an associated trace formula for a pair of operators of positive-type, extending a classical trace formula. On the other hand, we continue a recent systematic study of boundary data maps, that is, 2 \\times 2 matrix-valued Dirichlet-to-Neumann and more generally, Robin-to-Robin maps, associated with one-dimensional Schr\\"odinger operators on a compact interval [0,R] with separated boundary conditions at 0 and R. One of the principal new results in this paper reduces an appropriately symmetrized (Fredholm) perturbation determinant to the 2\\times 2 determinant of the underlying boundary data map. In addition, as a concrete application of the abstract approach in the first part of this paper, we establish the trace formula for resolvent differences of self-adjoint Schr\\"odinger operators corresponding to different (separated) boundary conditions in terms of boundary data maps.

  6. Combustion-turbulence interaction in the turbulent boundary layer over a hot surface

    SciTech Connect (OSTI)

    Ng, T.T.; Cheng, R.K.; Robben, F.; Talbot, L.

    1982-01-01T23:59:59.000Z

    The turbulence-combustion interaction in a reacting turbulent boundary layer over a heated flat plate was studied. Ethylene/air mixture with equivalence ratio of 0.35 was used. The free stream velocity was 10.5 m/s and the wall temperature was 1250/sup 0/K. Combustion structures visualization was provided by high-speed schlieren photographs. Fluid density statistics were deduced from Rayleigh scattering intensity measurements. A single-component laser Doppler velocimetry system was used to obtain mean and root-mean-square velocity distributions, the Reynolds stress, the streamwise and the cross-stream turbulent kinetic energy diffusion, and the production of turbulent kinetic energy by Reynolds stress. The combustion process was dominated by large-scale turbulent structures of the boundary layer. Combustion causes expansion of the boundary layer. No overall self-similarity is observed in either the velocity or the density profiles. Velocity fluctuations were increased in part of the boundary layer and the Reynolds stress was reduced. The turbulent kinetic energy diffusion pattern was changed significantly and a modification of the boundary layer assumption will be needed when dealing with this problem analytically. 11 figures, 1 table.

  7. Temporal variability of the trade wind inversion: Measured with a boundary layer vertical profiler. Master's thesis

    SciTech Connect (OSTI)

    Grindinger, C.M.

    1992-05-01T23:59:59.000Z

    This study uses Hawaiian Rainband Project (HaRP) data, from the summer of 1991, to show a boundary layer wind profiler can be used to measure the trade wind inversion. An algorithm has been developed for the profiler that objectively measures the depth of the moist oceanic boundary layer. The Hilo inversion, measured by radiosonde, is highly correlated with the moist oceanic boundary layer measured by the profiler at Paradise Park. The inversion height on windward Hawaii is typically 2253 + or - 514 m. The inversion height varies not only on a daily basis, but on less than an hourly basis. It has a diurnal, as well as a three to four day cycle. There appears to be no consistent relationship between inversion height and precipitation. Currently, this profiler is capable of making high frequency (12 minute) measurements of the inversion base variation, as well as other features.

  8. Solutions of Laplace's equation with simple boundary conditions, and their applications for capacitors with multiple symmetries

    E-Print Network [OSTI]

    Morales, Mayckol; Herrera, William J

    2015-01-01T23:59:59.000Z

    We find solutions of Laplace's equation with specific boundary conditions (in which such solutions take either the value zero or unity in each surface) using a generic curvilinear system of coordinates. Such purely geometrical solutions (that we shall call Basic Harmonic Functions BHF's) are utilized to obtain a more general class of solutions for Laplace's equation, in which the functions take arbitrary constant values on the boundaries. On the other hand, the BHF's are also used to obtain the capacitance of many electrostatic configurations of conductors. This method of finding solutions of Laplace's equation and capacitances with multiple symmetries is particularly simple, owing to the fact that the method of separation of variables becomes much simpler under the boundary conditions that lead to the BHF's. Examples of application in complex symmetries are given. Then, configurations of succesive embedding of conductors are also examined. In addition, expressions for electric fields between two conductors a...

  9. Heat Transfer Boundary Conditions in the RELAP5-3D Code

    SciTech Connect (OSTI)

    Richard A. Riemke; Cliff B. Davis; Richard R. Schultz

    2008-05-01T23:59:59.000Z

    The heat transfer boundary conditions used in the RELAP5-3D computer program have evolved over the years. Currently, RELAP5-3D has the following options for the heat transfer boundary conditions: (a) heat transfer correlation package option, (b) non-convective option (from radiation/conduction enclosure model or symmetry/insulated conditions), and (c) other options (setting the surface temperature to a volume fraction averaged fluid temperature of the boundary volume, obtaining the surface temperature from a control variable, obtaining the surface temperature from a time-dependent general table, obtaining the heat flux from a time-dependent general table, or obtaining heat transfer coefficients from either a time- or temperature-dependent general table). These options will be discussed, including the more recent ones.

  10. Converting Boundary Representation Solid Models to Half-Space Representation Models for Monte Carlo Analysis

    SciTech Connect (OSTI)

    Davis JE, Eddy MJ, Sutton TM, Altomari TJ

    2007-03-01T23:59:59.000Z

    Solid modeling computer software systems provide for the design of three-dimensional solid models used in the design and analysis of physical components. The current state-of-the-art in solid modeling representation uses a boundary representation format in which geometry and topology are used to form three-dimensional boundaries of the solid. The geometry representation used in these systems is cubic B-spline curves and surfaces--a network of cubic B-spline functions in three-dimensional Cartesian coordinate space. Many Monte Carlo codes, however, use a geometry representation in which geometry units are specified by intersections and unions of half-spaces. This paper describes an algorithm for converting from a boundary representation to a half-space representation.

  11. Strain Heterogeneity and Damage Nucleation at Grain Boundaries during Monotonic Deformation in Commercial Purity Titanium

    SciTech Connect (OSTI)

    Bieler, T. R. [Michigan State University, East Lansing; Crimp, M. A. [Michigan State University, East Lansing; Yang, Y. [Michigan State University, East Lansing; Eisenlohr, P. [Max-Planck-Institut fur Eisenforschung, Germany; Mason, D. E. [Albion College; Liu, W. [Argonne National Laboratory (ANL); Ice, Gene E [ORNL

    2009-01-01T23:59:59.000Z

    Heteroeneous strain was analyzed in polycrystalline, commercial-purity titanium using many experimental techniques that provide information about microstructure, dislocation arrangement, grain orientation, orientation gradients, surface topography, and local strain gradients. The recrystallized microstructure with 50-200 ?m grains was extensively characterized before and after deformation using 4-point bending to strains between 2% and 15%. Extremely heterogeneous deformation occurred along some grain boundaries, leading to orientation gradients exceeding 10{sup o} over 10-20 {micro}m. Patches of highly characterized microstructure were modeled using crystal plasticity finite element (CPFE) analysis to simulate the deformation to evaluate the ability of the CPFE model to capture local deformation processes. Damage nucleation events were identified that are associated with twin interactions with grain boundaries. Progress toward identifying fracture initiation criteria based upon slip and twin interactions with grain boundaries is illustrated with related CPFE simulations of deformation in a TiAl alloy.

  12. All bulk and boundary unitary cubic curvature theories in three dimensions

    SciTech Connect (OSTI)

    Guellue, Ibrahim; Sisman, Tahsin Cagri; Tekin, Bayram [Department of Physics, Middle East Technical University, 06531, Ankara (Turkey)

    2011-01-15T23:59:59.000Z

    We construct all the bulk and boundary unitary cubic curvature parity invariant gravity theories in three dimensions in (anti)-de Sitter spaces. For bulk unitarity, our construction is based on the principle that the free theory of the cubic curvature theory reduces to one of the three known unitary theories which are the cosmological Einstein-Hilbert theory, the quadratic theory of the scalar curvature, or the new massive gravity (NMG). Bulk and boundary unitarity in NMG is in conflict; therefore, cubic theories that are unitary both in the bulk and on the boundary have free theories that reduce to the other two alternatives. We also study the unitarity of the Born-Infeld extensions of NMG to all orders in curvature.

  13. The northern boundary of the desert tortoise range on the Nevada Test Site

    SciTech Connect (OSTI)

    Rautenstrauch, K.R.; Brown, G.A.; Goodwin, R.G.

    1994-12-01T23:59:59.000Z

    A study was conducted in 1993 to more accurately define the northern boundary of the range of desert tortoises (Gopherus agassizii) on the Nevada Test Site. Eighty-six transects totaling 338.2 km were walked along this boundary and 53 tortoise signs were recorded. Tortoise signs were found all along the northern edge of Jackass and Frenchman flats. Signs were found north of those valleys only in the Calico Hills at the south end of Topopah Valley and in the CP Hills at the extreme southern end of Yucca Flat. A revised map of the range of desert tortoises on NTS is presented. This information can be used by the US Department of Energy to determine whether activities conducted along or near this boundary will affect desert tortoises.

  14. Boundary Behavior of the Ginzburg-Landau Order Parameter in the Surface Superconductivity Regime

    E-Print Network [OSTI]

    M. Correggi; N. Rougerie

    2015-01-27T23:59:59.000Z

    We study the 2D Ginzburg-Landau theory for a type-II superconductor in an applied magnetic field varying between the second and third critical value. In this regime the order parameter minimizing the GL energy is concentrated along the boundary of the sample and is well approximated to leading order by a simplified 1D profile in the direction perpendicular to the boundary. Motivated by a conjecture of Xing-Bin Pan, we address the question of whether this approximation can hold uniformly in the boundary region. We prove that this is indeed the case as a corollary of a refined, second order energy expansion including contributions due to the curvature of the sample. Local variations of the GL order parameter are controlled by the second order term of this energy expansion, which allows us to prove the desired uniformity of the surface superconductivity layer.

  15. Particulate immersed boundary method for complex fluid-particle interaction problems with heat transfer

    E-Print Network [OSTI]

    Zhang, Hao; Trias, F Xavier; Yu, Aibing; Tan, Yuanqiang; Oliva, Assensi

    2015-01-01T23:59:59.000Z

    In our recent work [H. Zhang, F.X. Trias, A. Oliva, D. Yang, Y. Tan, Y. Sheng. PIBM: Particulate immersed boundary method for fluid-particle interaction problems. Powder Technology. 272(2015), 1-13.], a particulate immersed boundary method (PIBM) for simulating fluid-particle multiphase flow was proposed and assessed in both two- and three-dimensional applications. In this study, the PIBM was extended to solve thermal interaction problems between spherical particles and fluid. The Lattice Boltzmann Method (LBM) was adopted to solve the fluid flow and temperature fields, the PIBM was responsible for the non-slip velocity and temperature boundary conditions at the particle surface, and the kinematics and trajectory of the solid particles were evaluated by the Discrete Element Method (DEM). Four case studies were implemented to demonstrate the capability of the current coupling scheme. Firstly, numerical simulation of natural convection in a two-dimensional square cavity with an isothermal concentric annulus was...

  16. Topological constraints in geometric deformation quantization on domains with multiple boundary components

    E-Print Network [OSTI]

    Razvan Teodorescu

    2014-12-24T23:59:59.000Z

    A topological constraint on the possible values of the universal quantization parameter is revealed in the case of geometric quantization on (boundary) curves diffeomorphic to $S^1$, analytically extended on a bounded domain in $\\mathbb{C}$, with $n \\ge 2$ boundary components. Unlike the case of one boundary component (such as the canonical Berezin quantization of the Poincar\\'e upper-half plane or the case of conformally-invariant 2D systems), the more general case considered here leads to a strictly positive minimum value for the quantization parameter, which depends on the geometrical data of the domain (specifically, the total area and total perimeter in the smooth case). It is proven that if the lower bound is attained, then $n=2$ and the domain must be annular, with a direct interpretation in terms of the global monodromy.

  17. Hamiltonian, Energy and Entropy in General Relativity with Non-Orthogonal Boundaries

    E-Print Network [OSTI]

    M. Francaviglia; M. Raiteri

    2001-07-23T23:59:59.000Z

    A general recipe to define, via Noether theorem, the Hamiltonian in any natural field theory is suggested. It is based on a Regge-Teitelboim-like approach applied to the variation of Noether conserved quantities. The Hamiltonian for General Relativity in presence of non-orthogonal boundaries is analysed and the energy is defined as the on-shell value of the Hamiltonian. The role played by boundary conditions in the formalism is outlined and the quasilocal internal energy is defined by imposing metric Dirichlet boundary conditions. A (conditioned) agreement with previous definitions is proved. A correspondence with Brown-York original formulation of the first principle of black hole thermodynamics is finally established.

  18. SREELS analysis of oxygen-rich inversion domain boundaries in aluminum nitride

    SciTech Connect (OSTI)

    Bruley, J.; Zhao, J.C.; Notis, M.R. [Lehigh Univ. Bethlehem, PA (United States). Dept. of Materials Science and Engineering; Westwood, A.D. [IBM T.J. Watson Research Center, Yorktown Heights, NY (United States); Youngman, R.A. [Carborundum Co., Phoenix, AZ (United States)

    1995-09-01T23:59:59.000Z

    Spatially resolved electron energy loss spectroscopy analysis has been conducted on planar inversion domain boundaries in aluminum nitride. The defects were found to contain 1.5 monolayers of oxygen, in agreement with the most recent structural model of Westwood. From variations in near-edge structure, the local atomic environments of both oxygen and aluminum are compared with {alpha}-Al{sub 2}O{sub 3}, {gamma}-Al{sub 2}O{sub 3} and {gamma}-AlON standards. Based upon this study the structure of the inversion domain boundary is found to resemble that of the cubic {gamma}-AlON spinel, and eliminates from consideration those structural models based upon {alpha}-Al{sub 2}O{sub 3}. Furthermore, quantification of the shape resonances provided Al-O bond-length data from the inversion domain boundary interface. These distances closely agree with the Youngman Model that has recently been further refined by Westwood et al.

  19. Phase transitions in a reaction-diffusion model on a line with boundaries

    SciTech Connect (OSTI)

    Khorrami, Mohammad, E-mail: mamwad@mailaps.org; Aghamohammadi, Amir, E-mail: mohamadi@alzahra.ac.ir [Department of Physics, Alzahra University, Tehran 19938-93973 (Iran, Islamic Republic of)] [Department of Physics, Alzahra University, Tehran 19938-93973 (Iran, Islamic Republic of)

    2014-03-15T23:59:59.000Z

    A one-dimensional model on a line of length L is investigated, which involves particle diffusion as well as single particle annihilation. There are also creation and annihilation at the boundaries. The static and dynamical behaviors of the system are studied. It is seen that the system could exhibit a dynamical phase transition. For small drift velocities, the relaxation time does not depend on the absorption rates at the boundaries. This is the fast phase. For large velocities, the smaller of the absorption rates at boundaries enter the relaxation rate and makes it longer. This is the slow phase. Finally, the effect of a random particle creation in the bulk is also investigated.

  20. The abstract boundary---a new approach to singularities of manifolds

    E-Print Network [OSTI]

    Susan M. Scott; Peter Szekeres

    1994-05-26T23:59:59.000Z

    A new scheme is proposed for dealing with the problem of singularities in General Relativity. The proposal is, however, much more general than this. It can be used to deal with manifolds of any dimension which are endowed with nothing more than an affine connection, and requires a family \\calc\\ of curves satisfying a {\\em bounded parameter property} to be specified at the outset. All affinely parametrised geodesics are usually included in this family, but different choices of family \\calc\\ will in general lead to different singularity structures. Our key notion is the {\\em abstract boundary\\/} or {\\em $a$-boundary\\/} of a manifold, which is defined for any manifold \\calm\\ and is independent of both the affine connection and the chosen family \\calc\\ of curves. The $a$-boundary is made up of equivalence classes of boundary points of \\calm\\ in all possible open embeddings. It is shown that for a pseudo-Riemannian manifold $(\\calm,g)$ with a specified family \\calc\\ of curves, the abstract boundary points can then be split up into four main categories---regular, points at infinity, unapproachable points and singularities. Precise definitions are also provided for the notions of a {\\em removable singularity} and a {\\em directional singularity}. The pseudo-Riemannian manifold will be said to be singularity-free if its abstract boundary contains no singularities. The scheme passes a number of tests required of any theory of singularities. For instance, it is shown that all compact manifolds are singularity-free, irrespective of the metric and chosen family \\calc.

  1. Computer Modeling of Transport of Oxidizing Species in Grain Boundaries during Zirconium Corrosion

    SciTech Connect (OSTI)

    Xian-Ming Bai; Yongfeng Zhang; Michael R. Tonks

    2014-06-01T23:59:59.000Z

    Zirconium (Zr) based alloys are widely used as the cladding materials in light-water reactors. The water-side corrosion of these alloys degrades their structural integrity and poses serious safety concerns. During the Zr corrosion process, a thin Zr oxide (ZrO2) layer forms on the alloy surface and serves as a barrier layer for further corrosion. The majority of the oxide has the monoclinic phase. At the transition region between the oxide and the metal, the oxide contains a thin layer of stabilized tetragonal phase. It is found that the texture of the tetragonal layer determines the protectiveness of the oxide for corrosion. The transport of oxidizing species, such as anion defects, cation defects, and electron through the tetragonal oxide layer could be the rate limiting step of the corrosion. The defect diffusion can be affected by the growing stresses and microstructures such as grain boundaries and dislocations. In this work molecular dynamics simulations are used to investigate the anion and cation diffusion in bulk and at grain boundaries in tetragonal ZrO2. The results show that defect diffusion at grain boundaries is complex and the behavior strongly depends on the grain boundary type. For most of the grain boundaries studied the defect diffusion are much slower than in the bulk, implying that grain boundaries may not be fast defect transport paths during corrosion. The connection between the modeling results and published experimental work will also be discussed. This work is funded by the Laboratory Directed Research and Development (LDRD) program at Idaho National Laboratory.

  2. Simulations of dislocation pile-ups at assymetric tilt boundaries in aluminum

    SciTech Connect (OSTI)

    Valone, Steven [Los Alamos National Laboratory; Wang, Jian M [Los Alamos National Laboratory; Hoagland, Richard C [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory

    2011-01-21T23:59:59.000Z

    Materials deformation processes are increasingly approachable through the both conventional and accelerated molecular dynamics. In one deformation process, dislocation pile-up at a grain boundary, a greater understanding is required as to how dislocations transmit through grain boundaries, causing plastic deformation, or reflect and reconstruct the grain boundary, but with no macroscopic deformation. Here dislocation pile-ups in an alwninum bicrystal with an asymmetric tilt grain boundary are simulated atomistically, introducing effects of dislocation interactions beyond linear elastic ones. The observed responses as functions of the number of explicitly modeled dislocations and the magnitude of the applied stress are discussed. Typical conditions for the simulations consist of thermal relaxation room temperature, five active dislocations inserted within a 6.5-million-atom cell, and an additional fourteen dislocations represented within the atomistic simulation by their elastic strain fields. The dislocations are initially distributed according to linear elastic estimates of their positions in a double-ended pile-up from a chosen far-field stress. The whole cell is allowed to relax according to a procedure to be described. In the ensuing simulations, the system is propagated for some substantial period of time (lOs of ps), followed by small increments of strain. After a number of such increments, we observe all of the anticipated events. Usually several of the closest dislocations are absorbed into the grain boundary, resulting in varying amounts of reconstruction. Reflections from the boundary are common and show a strong dependence on sample thickness. Transmission events are seen on both slip systems in the other grain. The particulars of these events will be described as well.

  3. Modeling to Support Groundwater Contaminant Boundaries for the Shoal Underground Nuclear Test

    SciTech Connect (OSTI)

    K. Pohlmann; G. Pohll; J. Chapman; A. Hassan; R. Carroll; C. Shirley

    2004-03-01T23:59:59.000Z

    Groundwater flow and radionuclide transport at the Shoal underground nuclear test are characterized using three-dimensional numerical models, based on site-specific hydrologic data. The objective of this modeling is to provide the flow and transport models needed to develop a contaminant boundary defining the extent of radionuclide-contaminated groundwater at the site throughout 1,000 years at a prescribed level of confidence. This boundary will then be used to manage the Project Shoal Area for the protection of the public and the environment.

  4. Modeling to Support Groundwater Contaminant Boundaries for the Shoal Underground Nuclear Test

    SciTech Connect (OSTI)

    K. Pohlmann; G. Pohll; J. Chapman; A. Hassan; R. Carroll; C. Shirley

    2004-03-01T23:59:59.000Z

    The purpose of this work is to characterize groundwater flow and contaminant transport at the Shoal underground nuclear test through numerical modeling using site-specific hydrologic data. The ultimate objective is the development of a contaminant boundary, a model-predicted perimeter defining the extent of radionuclide-contaminated groundwater from the underground test throughout 1,000 years at a prescribed level of confidence. This boundary will be developed using the numerical models described here, after they are approved for that purpose by DOE and NDEP.

  5. Grain refinement and partitioning of impurities in the grain boundaries of a colloidal polycrystal

    E-Print Network [OSTI]

    Neda Ghofraniha; Elisa Tamborini; Julian Oberdisse; Luca Cipelletti; Laurence Ramos

    2012-03-29T23:59:59.000Z

    We study the crystallization of a colloidal model system in presence of secondary nanoparticles acting as impurities. Using confocal microscopy, we show that the nanoparticles segregate in the grain boundaries of the colloidal polycrystal. We demonstrate that the texture of the polycrystal can be tuned by varying independently the nanoparticle volume fraction and the crystallization rate, and quantify our findings using standard models for the nucleation and growth of crystalline materials. Remarkably, we find that the efficiency of the segregation of the nanoparticles in the grain-boundaries is determined solely by the typical size of the crystalline grains.

  6. Grain boundary migration induced segregation in V-Cr-Ti alloys

    SciTech Connect (OSTI)

    Gelles, D.S. [Pacific Northwest National Lab., Richland, WA (United States); Ohnuki, S.; Takahashi, H. [Univ. of Hokkaido (Japan)

    1996-10-01T23:59:59.000Z

    Analytical electron microscopy results are reported for a series of vanadium alloys irradiated in the HFIR JP23 experiment at 500{degrees}C. Alloys were V-5Cr-5Ti and pure vanadium which are expected to have transmuted to V-15Cr-5Ti and V-10Cr following irradiation. Analytical microscopy confirmed the expected transmutation occurred and showed redistribution of Cr and Ti resulting from grain boundary migration in V-5Cr-5Ti, but in pure V, segregation was reduced and no clear trends as a function of position near a boundary were identified.

  7. The No-Boundary Wave Function and the Duration of the Inflationary Period

    E-Print Network [OSTI]

    A. Lukas

    1994-09-07T23:59:59.000Z

    For the simplest minisuperspace model based on a homogeneous, isotropic metric and a minimally coupled scalar field we derive analytic expressions for the caustic which separates Euklidean and Minkowskian region and its breakdown value $\\p_*$. This value represents the prediction of the no-boundary wave function for the scalar field at the beginning of inflation. We use our results to search for inflationary models which can render the no-boundary wave function consistent with the requirement of a sufficiently long inflationary period.

  8. Almansi-type boundary conditions for electric potential inducing flexure in linear piezoelectric beams

    E-Print Network [OSTI]

    F. dell'Isola; L. Rosa

    2010-07-09T23:59:59.000Z

    Using the recent results found in [1, 2] we prove that it is possible to induce flexur in linear piezoelectric beams by means of quadratic Almansi type boundary conditions for the electric potential. Beams constituted by transversely isotropic piezoelectric materials whose symmetry axis is parallel to the axis of the beam are considered. Our choice of boundary conditions for the electric potential has been suggested by the results found in [1, 3]. An explicit expression of material parameters that influenc flexur is given in terms of piezoelectric moduli.

  9. Gradient zone-boundary control in salt-gradient solar ponds

    DOE Patents [OSTI]

    Hull, J.R.

    1982-09-29T23:59:59.000Z

    A method and apparatus for suppressing zone boundary migration in a salt gradient solar pond includes extending perforated membranes across the pond at the boundaries, between the convective and non-convective zones, the perforations being small enough in size to prevent individual turbulence disturbances from penetrating the hole, but being large enough to allow easy molecular diffusion of salt thereby preventing the formation of convective zones in the gradient layer. The total area of the perforations is a sizeable fraction of the membrane area to allow sufficient salt diffusion while preventing turbulent entrainment into the gradient zone.

  10. Effects of passive porous walls on the first Mack mode instability of hypersonic boundary layers over a sharp cone.

    E-Print Network [OSTI]

    Michael, Vipin George

    2013-01-01T23:59:59.000Z

    ??Passive porous coatings have been proposed in literature as a means of delaying transition to turbulence in hypersonic boundary layers. The nonlinear stability of hypersonic… (more)

  11. Creating a single twin boundary between two CdTe (111) wafers with controlled rotation angle by wafer bonding

    SciTech Connect (OSTI)

    Sun, Ce; Lu, Ning; Wang, Jinguo; Lee, Jihyung; Peng, Xin; Kim, Moon J., E-mail: moonkim@utdallas.edu [Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Klie, Robert F. [Department of Physics, University of Illinois at Chicago, Chicago, Illinois 60607 (United States)] [Department of Physics, University of Illinois at Chicago, Chicago, Illinois 60607 (United States)

    2013-12-16T23:59:59.000Z

    The single twin boundary with crystallographic orientation relationship (1{sup ¯}1{sup ¯}1{sup ¯})//(111) [01{sup ¯}1]//[011{sup ¯}] was created by wafer bonding. Electron diffraction patterns and high-resolution transmission electron microscopy images demonstrated the well control of the rotation angle between the bonded pair. At the twin boundary, one unit of wurtzite structure was found between two zinc-blende matrices. High-angle annular dark-field scanning transmission electron microscopy images showed Cd- and Te-terminated for the two bonded portions, respectively. The I-V curve across the twin boundary showed increasingly nonlinear behavior, indicating a potential barrier at the bonded twin boundary.

  12. Isolating Effects of Water Table Dynamics, Terrain, and Soil Moisture Heterogeneity on the Atmospheric Boundary Layer Using Coupled Models

    E-Print Network [OSTI]

    Rihani, Jehan

    2010-01-01T23:59:59.000Z

    boundary conditions of wind, potential temperature, andvariables such as winds, potential temperature, rainfall,variables such as wind speed, potential temperature, and

  13. Nature and evolution of the fusion boundary in ferritic-austenitic dissimilar weld metals. Part 1 -- Nucleation and growth

    SciTech Connect (OSTI)

    Nelson, T.W.; Lippold, J.C.; Mills, M.J.

    1999-10-01T23:59:59.000Z

    A fundamental investigation of fusion boundary microstructure evolution in dissimilar-metal welds (DMWs) between ferritic base metals and a face-centered-cubic (FCC) filler metal was conducted. The objective of the work presented here was to characterize the nature and character of the elevated-temperature fusion boundary to determine the nucleation and growth characteristics of DMWs. Type 409 ferritic stainless steel and 1080 pearlitic steel were utilized as base metal substrates, and Monel (70Ni-30Cu) was used as the filler metal. The Type 409 base metal provided a fully ferritic or body-centered-cubic (BCC) substrate at elevated temperatures and exhibited no on-cooling phase transformations to mask or disguise the original character of the fusion boundary. The 1080 pearlitic steel was selected because it is austenitic at the solidus temperature, providing an austenite substrate at the fusion boundary. The weld microstructure generated with each of the base metals in combination with Monel was fully austenitic. In the Type 409/Monel system, there was no evidence of epitaxial nucleation and growth as normally observed in homogeneous weld metal combinations. The fusion boundary in this system exhibited random grain boundary misorientations between the heat-affected zone (HAZ) and weld metal grains. In the 1080/Monel system, evidence of normal epitaxial growth was observed at the fusion boundary, where solidification and HAZ grain boundaries converged. The fusion boundary morphologies are a result of the crystal structure present along the fusion boundary during the initial stages of solidification. Based on the results of this investigation, a model for heterogeneous nucleation along the fusion boundary is proposed when the base and weld metals exhibit ferritic (BCC) and FCC crystal structures, respectively.

  14. Study on grain boundary character and strain distribution of intergranular cracking in the CGHAZ of T23 steel

    SciTech Connect (OSTI)

    Jin, Y.J.; Lu, H., E-mail: shweld@sjtu.edu.cn; Yu, C.; Xu, J.J.

    2013-10-15T23:59:59.000Z

    Intergranular reheat cracking in the coarse-grained heat-affected zone of T23 steel was produced by strain to fracture tests on a Gleeble 3500 thermal–mechanical simulator. Then the grain boundary character, as well as the strain distribution after reheat crack propagation, was studied by electron backscatter diffraction technique. The results showed that incoherent ?3 boundaries were seldom found on the prior austenite grain boundaries. Therefore, only the type of random high-angle boundaries played a crucial role in the intergranular cracking. Microstructurally cavities and small cracks were preferentially initiated from high-angle grain boundaries. Low-angle grain boundaries and high-angle ones with misorientation angles less than 15° were more resistant to the cracking. More importantly, the fraction of high-angle grain boundaries increased with the plastic strain induced by both temperature gradient and stress in the coarse-grained heat-affected zone, which contributed to the crack initiation and propagation. Furthermore, the strain distributions in the vicinity of cavities and cracks revealed the accommodation processes of plastic deformation during stress relaxation. It also reflected the strength differences between grain interior and grain boundary at different heat-treated temperatures, which had a large influence on the cracking mechanism. - Highlights: • The coincidence site lattice boundaries play little role in the reheat cracking. • Cavity and crack occur at high-angle grain boundaries rather than low-angle ones. • The strain leads low-angle grain boundaries to transform to high-angle ones. • Strain distribution differs for cavity and crack zones at different temperatures.

  15. Wave-driven wind jets in the marine atmospheric boundary layer

    E-Print Network [OSTI]

    Reading, University of

    Wave-driven wind jets in the marine atmospheric boundary layer Kirsty E. Hanley Stephen E. Belcher;Abstract The interaction between ocean surface waves and the overlying wind leads to a transfer of momentum can also be transferred upwards when long wavelength waves, characteristic of re- motely generated

  16. Behavior of Turbulent Structures within a Mach 5 Mechanically Distorted Boundary Layer

    E-Print Network [OSTI]

    Peltier, Scott Jacob

    2013-08-05T23:59:59.000Z

    field of incompressible boundary layer, taken from Adrian et al. (2000). ............................................................................... 138 Figure 6.15 Schematic of an individual hairpin vortex, describing the sweep and ejection... hairpin vortex, identifying the motions contributing to sweeps and ejections ....................................................................................... 235 Figure 7.46 Illustrations of the possible mechanisms contributing to the reduced...

  17. Mantle transition zone beneath the Caribbean-South American plate boundary and its tectonic implications

    E-Print Network [OSTI]

    Niu, Fenglin

    Mantle transition zone beneath the Caribbean-South American plate boundary and its tectonic seismic network of Venezuela to study the mantle transition zone structure beneath the Caribbean Caribbean, the 410-km is featured by a narrow (200 km EW) 25-km uplift extending in the NS direction around

  18. Jump conditions and dynamic surface tension at permeable interfaces such as the inner core boundary

    E-Print Network [OSTI]

    Jump conditions and dynamic surface tension at permeable interfaces such as the inner core boundary as the density and viscosity changes. Independently of any intrinsic surface tension, a dynamic surface tension, a possibly anisotropic surface tension and terms including an interface mass density. In pratice

  19. Three-Dimensional Nonreflecting Boundary Conditions for Swirling Flow in Turbomachinery

    E-Print Network [OSTI]

    Giles, Mike

    Three-Dimensional Nonreflecting Boundary Conditions for Swirling Flow in Turbomachinery Pierre turbomachinery problems. Based on the use of precalculated far-field acoustic eigenmodes for a mean flow THERE are different approaches to analyze turbomachinery unsteadiness. These methods vary from the use of linearized

  20. A MATLAB Code for Three Dimensional Linear Elastostatics using Constant Boundary Elements

    E-Print Network [OSTI]

    P, Kirana Kumara

    2013-01-01T23:59:59.000Z

    Present work presents a code written in the very simple programming language MATLAB, for three dimensional linear elastostatics, using constant boundary elements. The code, in full or in part, is not a translation or a copy of any of the existing codes. Present paper explains how the code is written, and lists all the formulae used. Code is verified by using the code to solve a simple problem which has the well known approximate analytical solution. Of course, present work does not make any contribution to research on boundary elements, in terms of theory. But the work is justified by the fact that, to the best of author's knowledge, as of now, one cannot find an open access MATLAB code for three dimensional linear elastostatics using constant boundary elements. Author hopes this paper to be of help to beginners who wish to understand how a simple but complete boundary element code works, so that they can build upon and modify the present open access code to solve complex engineering problems quickly and easi...

  1. Continuum Models of Carbon Nanotube-Based Composites Using the Boundary Element Method

    E-Print Network [OSTI]

    Liu, Yijun

    Continuum Models of Carbon Nanotube-Based Composites Using the Boundary Element Method Y.J. Liu)-based composites. Carbon nanotubes, formed conceptually by rolling thin graphite sheets, have been found to be extremely stiff, strong and resilient, and therefore may be ideal for reinforcing composite materials

  2. Conservation and Diversity of Seed Associated Endophytes in Zea across Boundaries of Evolution,

    E-Print Network [OSTI]

    Raizada, Manish N.

    Conservation and Diversity of Seed Associated Endophytes in Zea across Boundaries of Evolution of Guelph, Guelph, Ontario, Canada Abstract Endophytes are non-pathogenic microbes living inside plants. We asked whether endophytic species were conserved in the agriculturally important plant genus Zea

  3. Acoustic Properties of Porous Coatings for Hypersonic Boundary-Layer Control

    E-Print Network [OSTI]

    Dabiri, John O.

    Acoustic Properties of Porous Coatings for Hypersonic Boundary-Layer Control Guillaume A. Brès for hypersonic laminar flow control. The reflection coefficient, characterizing the ratio of the reflected wave of incidence, for coatings of different porosities, at various acoustic Reynolds numbers relevant to hypersonic

  4. Effect of Finite-rate Chemical Reactions on Turbulence in Hypersonic Turbulent Boundary Layers

    E-Print Network [OSTI]

    Martín, Pino

    Effect of Finite-rate Chemical Reactions on Turbulence in Hypersonic Turbulent Boundary Layers Lian on future air-breathing hypersonic cruise vehicles will be turbulent and chemically reacting. To aid the design of such vehicles, a greater understanding of turbulent hypersonic flows is needed. Although

  5. Direct Numerical Simulation of a Hypersonic Turbulent Boundary Layer on a Large Domain

    E-Print Network [OSTI]

    Martín, Pino

    Direct Numerical Simulation of a Hypersonic Turbulent Boundary Layer on a Large Domain Stephan Priebe , M. Pino Mart´in The direct numerical simulation (DNS) of a spatially-developing hypersonic There are few studies of hypersonic flows at Mach number greater than 5 and few involve the measurement of mean

  6. On the role of boundary conditions for CIP stabilization of higher order finite elements

    E-Print Network [OSTI]

    Schieweck, Friedhelm

    On the role of boundary conditions for CIP stabilization of higher order finite elements Friedhelm Schieweck 13.11.2007 Abstract We investigate the Continuous Interior Penalty (CIP) stabilization method even in the limit case where the parameter of the CIP stabilization is zero, i.e., where the standard

  7. The equilibrium crystal shape of strontium titanate and its relationship to the grain boundary plane distribution

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    1 The equilibrium crystal shape of strontium titanate and its relationship to the grain crystal shape (ECS) of a model system, strontium titanate, is compared with the grain boundary plane distribution (GBPD) as a function of temperature. Strontium titanate has a pronounced surface energy anisotropy

  8. EUROPEAN CONFERENCE FOR AEROSPACE SCIENCES Shock Wave / Boundary Layer Interactions in Hypersonic

    E-Print Network [OSTI]

    and a combina- tion of laminar and turbulent (transitional) computations as well as preliminary 3D simulations the impact on the shock / boundary layer interaction and on the size of the shock induced separation. Laminar have been conducted and show the experimental shock-tunnel results to be influenced by transition and 3

  9. NPD Project leaders as team boundary spanners: Relational antecedents and performance outcomes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 NPD Project leaders as team boundary spanners: Relational antecedents and performance outcomes S to the performance of NPD projects has been widely studied in the project management literature (Aronson et al., 2008, and many other important aspects of project management, project leaders' professional qualifications

  10. Atomic-Scale Mapping of Thermoelectric Power on Graphene: Role of Defects and Boundaries

    E-Print Network [OSTI]

    Feenstra, Randall

    by conductance measurements alone. Indeed, the thermoelectric properties of this two-dimensional material have scattering effects in thermoelectric materials. An alternative way to study the thermoelectric properties1 Atomic-Scale Mapping of Thermoelectric Power on Graphene: Role of Defects and Boundaries Jewook

  11. Multilevel preconditioning for the boundary concentrated T. Eibner J.M. Melenk

    E-Print Network [OSTI]

    Melenk, Jens Markus

    order elliptic boundary value problems where the di#erential equation has analytic coe m=0 # v#Im V m v # . Here, the spaces S v consist of all functions of VN that are supported by the patch associated with the vertex v; the second term, # M m=0 # v#Im V m v comprises one­ dimensional

  12. Cosmic ray diffusive acceleration at shock waves with finite upstream and downstream escape boundaries

    E-Print Network [OSTI]

    M. Ostrowski; R. Schlickeiser

    1996-04-18T23:59:59.000Z

    In the present paper we discuss the modifications introduced into the first-order Fermi shock acceleration process due to a finite extent of diffusive regions near the shock or due to boundary conditions leading to an increased particle escape upstream and/or downstream the shock. In the considered simple example of the planar shock wave we idealize the escape phenomenon by imposing a particle escape boundary at some distance from the shock. Presence of such a boundary (or boundaries) leads to coupled steepening of the accelerated particle spectrum and decreasing of the acceleration time scale. It allows for a semi-quantitative evaluation and, in some specific cases, also for modelling of the observed steep particle spectra as a result of the first-order Fermi shock acceleration. We also note that the particles close to the upper energy cut-off are younger than the estimate based on the respective acceleration time scale. In Appendix A we present a new time-dependent solution for infinite diffusive regions near the shock allowing for different constant diffusion coefficients upstream and downstream the shock.

  13. Flowfield and wall pressure characteristics downstream of a boundary layer suction device.

    E-Print Network [OSTI]

    Tinney, Charles E.

    Flowfield and wall pressure characteristics downstream of a boundary layer suction device. Meagan A-dimensional slit can significantly reduce the fluctuating wall pressure immediately downstream of the suction slit momentum regions of the flow with the wall at the downstream edge of the suction slit. The third region

  14. Stability Crossing Boundaries and Fragility Characterization of PID Controllers for SISO

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Stability Crossing Boundaries and Fragility Characterization of PID Controllers for SISO Systems-input-single-output (SISO) systems subject to input (or output) delays in the presence of PID-controllers. More precisely analysis as well as for the fragility of such PID controllers. The proposed approach is illustrated

  15. Boundary-trapped, inhalant siphon, and drain flows: Pipe entry revisited numerically

    E-Print Network [OSTI]

    Jumars, Pete

    Boundary-trapped, inhalant siphon, and drain flows: Pipe entry revisited numerically Peter A just inside these inlets have relied on solutions to pipe entry that posit uniform entrance velocity. I for 0.01 #Re #2000.Re is the pipe Reynolds number, the product of mean capillary flow speed

  16. Fluid structure and boundary slippage in nanoscale liquid films Nikolai V. Priezjev

    E-Print Network [OSTI]

    Priezjev, Nikolai V.

    Fluid structure and boundary slippage in nanoscale liquid films Nikolai V. Priezjev Department of Mechanical Engineering, Michigan State University, East Lansing, Michigan 48824 (Dated: August 19, 2011 in micro and nanofluidic systems and, in particular, in accurate prediction of fluid flows with slip

  17. MULTIPHASE FLOW SIMULATION WITH VARIOUS BOUNDARY CONDITIONS Z. CHEN, R. E. EWING, and M. ESPEDAL

    E-Print Network [OSTI]

    Ewing, Richard E.

    commonly used boundary conditions for groundwater hydrology and petroleum engineering problems can­ water hydrology and petroleum engineering is considered. The phase flow equations are given be incorporated into the pressure­saturation formu­ lation. INTRODUCTION In petroleum reservoir simulation

  18. Well test imaging - a new method for determination of boundaries from well test data

    SciTech Connect (OSTI)

    Slevinsky, B.A.

    1997-08-01T23:59:59.000Z

    A new method has been developed for analysis of well test data, which allows the direct calculation of the location of arbitrary reservoir boundaries which are detected during a well test. The method is based on elements of ray tracing and information theory, and is centered on the calculation of an instantaneous {open_quote}angle of view{close_quote} of the reservoir boundaries. In the absence of other information, the relative reservoir shape and boundary distances are retrievable in the form of a Diagnostic Image. If other reservoir information, such as 3-D seismic, is available; the full shape and orientation of arbitrary (non-straight line or circular arc) boundaries can be determined in the form of a Reservoir Image. The well test imaging method can be used to greatly enhance the information available from well tests and other geological data, and provides a method to integrate data from multiple disciplines to improve reservoir characterization. This paper covers the derivation of the analytical technique of well test imaging and shows examples of application of the technique to a number of reservoirs.

  19. Dorsoventral boundary for organizing growth and planar polarity in the Drosophila eye

    E-Print Network [OSTI]

    Singh, Amit

    eye Amit Singh, Janghoo Lim and Kwang-Wook Choi Department of Molecular and Cellular Biology, Program selector function of Iro-C in head-eye compartments . . . . . . . . 65 4. Dorsoventral boundary.2. Function of peripodial membrane in DV patterning and growth . . . . . . 73 6. Domain-specific growth of eye

  20. Approaches to defining a planetary boundary for biodiversity Georgina M. Mace a,1,

    E-Print Network [OSTI]

    extinction rate and species richness are weak metrics for this purpose, and they do not scale well from local current rates of extinction put the Earth system furthest outside the safe operating space. Here we review the evidence to support a boundary based on extinction rates and identify weaknesses with this metric and its

  1. The Cretaceous/ Tertiary boundary: sedimentology and micropalaeontology at El Mulato section, NE Mexico

    E-Print Network [OSTI]

    Royer, Dana

    The Cretaceous/ Tertiary boundary: sedimentology and micropalaeontology at El Mulato section, NE and sedimentological analysis of this transition at the El Mulato section (NE Mexico), in order to infer the little Palaeogene Velasco Formation, there is a 2-m-thick Clastic Unit. Strati- graphical and sedimentological ana

  2. A -moment approach to monotonic boundaries estimation: with applications in econometric and nuclear fields

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A -moment approach to monotonic boundaries estimation: with applications in econometric and nuclear application concerns frontier estimation in econometrics : the data typically consist of input factors Xi R of outputs y. Econometric considerations lead to the natural assumption that the cost function is isotonic

  3. From Finite to Infinite Volumes: Removal of Boundaries in Diffuse Wave Imaging Jorge Ripoll

    E-Print Network [OSTI]

    Lorenzo, Jorge Ripoll

    outside the volume to anywhere inside the volume and vice versa. Such transformation is not possible that removes the contribution of the boundaries on the measurements from highly scattering media, transforming]. The computation times required typically scale with a power law to the data-set size, and calculation requirements

  4. Crystallographic Characteristics of Grain Boundaries in Dense Yttria-Stabilized Zirconia

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    polycrystalline yttria-stabilized zirconia, to understand interfacial crystallography in solid oxide fuel cells correlated to the boundary energy distribution. Introduction Solid oxide fuel cells (SOFCs) are attractive The performance of a SOFC is coupled strongly to microstructural features, which have now been nearly optimized

  5. A MOVING-BOUNDARY PROBLEM FOR CONCRETE CARBONATION: GLOBAL EXISTENCE AND UNIQUENESS OF

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    in a porous solid ­ concrete ­ which incorporates slow diffusive transport, interfacial exchange between wet of gaseous CO2 from the atmosphere penetrate the concrete via the unsaturated porous matrix. After enteringA MOVING-BOUNDARY PROBLEM FOR CONCRETE CARBONATION: GLOBAL EXISTENCE AND UNIQUENESS OF WEAK

  6. On asymptotic effects of boundary perturbations in exponentially shaped Josephson junctions

    E-Print Network [OSTI]

    Monica De Angelis; Pasquale Renno

    2014-01-02T23:59:59.000Z

    A parabolic integro differential operator L, suitable to describe many phenomena in various physical fields, is considered. By means of equivalence between L and the third order equation describing the evolution inside an exponentially shaped Josephson junction (ESJJ), an asymptotic analysis for (ESJJ) is achieved, explicitly evaluating, boundary contributions related to the Dirichlet problem.

  7. Lidar Investigation of Tropical Nocturnal Boundary Layer Aerosols and Cloud Macrophysics

    SciTech Connect (OSTI)

    Manoj, M. G.; Devara, PC S.; Taraphdar, Sourav

    2013-10-01T23:59:59.000Z

    Observational evidence of two-way association between nocturnal boundary layer aerosols and cloud macrophysical properties under different meteorological conditions is reported in this paper. The study has been conducted during 2008-09 employing a high space-time resolution polarimetric micro-pulse lidar over a tropical urban station in India. Firstly, the study highlights the crucial role of boundary layer aerosols and background meteorology on the formation and structure of low-level stratiform clouds in the backdrop of different atmospheric stability conditions. Turbulent mixing induced by the wind shear at the station, which is associated with a complex terrain, is found to play a pivotal role in the formation and structural evolution of nocturnal boundary layer clouds. Secondly, it is shown that the trapping of energy in the form of outgoing terrestrial radiation by the overlying low-level clouds can enhance the aerosol mixing height associated with the nocturnal boundary layer. To substantiate this, the long-wave heating associated with cloud capping has been quantitatively estimated in an indirect way by employing an Advanced Research Weather Research and Forecasting (WRF-ARW) model version 2.2 developed by National Center for Atmospheric Research (NCAR), Colorado, USA, and supplementary data sets; and differentiated against other heating mechanisms. The present investigation as well establishes the potential of lidar remote-sensing technique in exploring some of the intriguing aspects of the cloud-environment relationship.

  8. Fast Prediction of Loadability Margins by Constructing a Small-Signal Stability Boundary

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    Fast Prediction of Loadability Margins by Constructing a Small-Signal Stability Boundary Based system. A novel approach is proposed in this paper for fast prediction of loadability margins to predict the loadability margins from any stable operating point along arbitrary loading directions through

  9. First-principles calculations of twin-boundary and stacking-fault energies in magnesium

    E-Print Network [OSTI]

    Chen, Long-Qing

    First-principles calculations of twin-boundary and stacking-fault energies in magnesium Y. Wang and stacking faults in metal magnesium have been calculated using first-principles supercell approach. Four. Keywords: Magnesium; Interfaces; Twinning; First-principles calculation Magnesium alloys are increasingly

  10. Boundary control for an industrial under-actuated tubular chemical reactor

    E-Print Network [OSTI]

    Ltd. All rights reserved. Keywords: Polystyrene; Tubular reactor; Control; Optimization; IndustrialBoundary control for an industrial under-actuated tubular chemical reactor D. Del Vecchio a , N and studied for an industrial under-actuated tubular chemical reactor. This work presents a case

  11. Alternate Designs of Ultrasonic Absorptive Coatings for Hypersonic Boundary Layer Control

    E-Print Network [OSTI]

    Dabiri, John O.

    -wall boundary condition. A particular case with a relatively shallow cavities and very high porosity showed number, wawb/µw Re Reynolds number, eUe/µe s Cavity spacing T Temperature t Time U Freestream streamwise of thermal protection systems (TPS).2,3 State-of- the-art active and reactive lam- inar flow control (LFC

  12. Boundary spanning, knowledge dynamics and emerging innovation systems early lessons from nanotechnology

    E-Print Network [OSTI]

    nanotechnology DIME Workshop "Industrial innovation dynamics and knowledge characteristics, exploring systems. Using nanotechnology as a case the paper focuses on analysing boundary spanning effects to capture possible changes in the knowledge base and search modes related to the rise of nanotechnology

  13. Grain-Boundary Grooving of Plasma-Sprayed Yttria-Stabilized Zirconia Thermal Barrier Coatings

    E-Print Network [OSTI]

    Trice, Rodney W.

    Grain-Boundary Grooving of Plasma-Sprayed Yttria-Stabilized Zirconia Thermal Barrier Coatings Engineering, West Lafayette, Indiana 47907 The focus of this study was to determine the mechanisms re- sponsible for the microstructural changes of plasma-sprayed 7 wt% Y2O3­ZrO2 thermal barrier coatings

  14. Randomly accelerated particle in a box: Mean absorption time for partially absorbing and inelastic boundaries

    E-Print Network [OSTI]

    Randomly accelerated particle in a box: Mean absorption time for partially absorbing and inelastic which is randomly accelerated by Gaussian white noise on the line segment 0 x 1 and is absorbed as soon accelerated particle which moves on the half line x 0 with an absorbing boundary at x=0. The motion

  15. Simulation of Biological Flow and Transport in Complex Geometries using Embedded Boundary /

    E-Print Network [OSTI]

    Simulation of Biological Flow and Transport in Complex Geometries using Embedded Boundary / Volume for modeling polymer fluids in irregular microscale geometries that enables long-time simulation of validation the constitutive behavior of polymer fluids. Complex flow environment geometries are represented on Cartesian grids

  16. Efficient Computation of the Pareto Boundary for the MISO Interference Channel with Perfect CSI

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Efficient Computation of the Pareto Boundary for the MISO Interference Channel with Perfect CSI,erik.larsson}@isy.liu.se Abstract--We consider the two-user multiple-input single- output (MISO) interference channel and the rate of the IFC is called a multiple-input single-output (MISO) This work was supported in part by the Swedish

  17. Oxygen Transport from the Outer Boundary of a Pulsating Arteriole Wall to the

    E-Print Network [OSTI]

    Salamon, Peter

    Oxygen Transport from the Outer Boundary of a Pulsating Arteriole Wall to the Surrounding Tissue In all living organisms, oxygen transport from arterioles to the surrounding tissue is critical for survival. However, the exact nature of the transport of oxygen from the arteriole to the surrounding tissue

  18. RIS-M-2612 ON TRANSPORT OF HELIUM TO GRAIN BOUNDARIES DURING IRRADIATION

    E-Print Network [OSTI]

    parameters determining the integrity and lifetime of the structural components of a fusion reactor. A diffusion calculation i s made of the flux of helium to a grain boundary. The flux i s found to depend interior. The calculated accumulation of helium i s in good agreement with the measured gas content

  19. Interfaces and Free Boundaries, 4 : 2002, 7188 A TOTALVARIATION SURFACE ENERGY MODEL FOR THIN FILMS OF

    E-Print Network [OSTI]

    Luskin, Mitchell

    Interfaces and Free Boundaries, 4 : 2002, 71­88 A TOTAL­VARIATION SURFACE ENERGY MODEL FOR THIN to model the energy on surfaces separating regions of di#erent variants. We find that the deformation energy modeled by # ## h |# 2 u| 2 dx, where # is a small positive strain­gradient coe#cient,# h

  20. IIT Architecture NOWNESS is our approach. There are no more boundaries, no

    E-Print Network [OSTI]

    Heller, Barbara

    IIT Architecture Chicago Graduate Programs #12;#12;NOWNESS is our approach. There are no more boundaries, no eternal forms. We should not attempt to define architecture in an all-encompassing way but instead make possible an architecture of freedom. Now is the time for opportunities of innovation. Now

  1. Atmospheric Environment 34 (2000) 2851}2863 Resolution of pollutant concentrations in the boundary layer

    E-Print Network [OSTI]

    Utah, University of

    Atmospheric Environment 34 (2000) 2851}2863 Resolution of pollutant concentrations in the boundary 1999 Abstract This paper investigates the solution of a 3D atmospheric dispersion problem using a time to solve the atmospheric di!usion equation. Preliminary studies of dispersion from a single source

  2. ON THE DrFF,US~VE CAVITATION OF ISOLATED GRAIN BOUNDARY FACETS TN

    E-Print Network [OSTI]

    ON THE DrFF,US~VE CAVITATION OF ISOLATED GRAIN BOUNDARY FACETS TN CREEPING POLYCRYSTALS J. R. RICE-Following concepts introduced by B. F. Dyson (Metal Sci.349 19761,the dilTusive cavitation of grain facets is considered in circumstances for which the cavitated fasts are well separated from one another. In this case

  3. eXtremes of heat conduction: Pushing the boundaries of the thermal

    E-Print Network [OSTI]

    Braun, Paul

    eXtremes of heat conduction: Pushing the boundaries of the thermal conductivity of materials David. · For example, simplest case of thermal conductivity where resistive scattering dominates C() v() l() d C for the highest thermal conductivity any material (higher conductivity than diamond) Yu et al. (2005) Maruyama

  4. Finite speed of propagation and local boundary conditions for wave equations with point interactions

    E-Print Network [OSTI]

    Pavel Kurasov; Andrea Posilicano

    2006-02-10T23:59:59.000Z

    We show that the boundary conditions entering in the definition of the self-adjoint operator describing the Laplacian plus a finite number of point interactions are local if and only if the corresponding wave equation has finite speed of propagation

  5. Continued Fraction Absorbing Boundary Conditions for Transient Elastic Wave Propagation Modeling

    E-Print Network [OSTI]

    Guddati, Murthy N.

    Continued Fraction Absorbing Boundary Conditions for Transient Elastic Wave Propagation Modeling Md of the truncated exterior. Development of an accurate ABC for transient elastic wave propagation problems are obtained by factoring the wave equation into outward and inward propagating operators and permitting only

  6. Boundary displacement measurements using multi-energy soft x-rays

    SciTech Connect (OSTI)

    Tritz, K., E-mail: ktritz@pppl.gov; Stutman, D. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Diallo, A.; LeBlanc, B. P. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Sabbagh, S. [Department of Applied Physics and Mathematics, Columbia University, New York City, New York 10027 (United States)

    2014-11-15T23:59:59.000Z

    The Multi-Energy Soft X-ray (ME-SXR) system on NSTX provides radial profiles of soft X-ray emission, measured through a set of filters with varying thickness, which have been used to reconstruct the electron temperature on fast time scales (?10?kHz). In addition to this functionality, here we show that the ME-SXR system can be used to measure the boundary displacement of the NSTX plasma with a few mm spatial resolution during magnetohydrodyamic (MHD) activity. Boundary displacement measurements can serve to inform theoretical predictions of neoclassical toroidal viscosity, and will be used to investigate other edge phenomena on NSTX-U. For example, boundary measurements using filtered SXR measurements can provide information on pedestal steepness and dynamic evolution leading up to and during edge localized modes (ELMs). Future applications include an assessment of a simplified, filtered SXR edge detection system as well as its suitability for real-time non-magnetic boundary feedback for ELMs, MHD, and equilibrium position control.

  7. The Low-Recycling Lithium Boundary and Implications for Plasma Transport

    E-Print Network [OSTI]

    Hammett, Greg

    The Low-Recycling Lithium Boundary and Implications for Plasma Transport Erik Michael Granstedt transport mechanism in high-temperature low-recycling fusion experiments, and in the absence of stabilizing hydrogen and impurity emission in LTX in order to determine the lower bound on recycling that can

  8. Microstructure of Josephson junctions: Effect on supercurrent transport in YBCO grain boundary and barrier layer junctions

    SciTech Connect (OSTI)

    Merkle, K.L.; Huang, Y.

    1998-01-01T23:59:59.000Z

    The electric transport of high-temperature superconductors, such as YBa{sub 2}Cu{sub 3}O{sub 7{minus}x} (YBCO), can be strongly restricted by the presence of high-angle grain boundaries (GB). This weak-link behavior is governed by the macroscopic GB geometry and the microscopic grain boundary structure and composition at the atomic level. Whereas grain boundaries present a considerable impediment to high current applications of high T{sub c} materials, there is considerable commercial interest in exploiting the weak-link-nature of grain boundaries for the design of microelectronic devices, such as superconducting quantum interference devices (SQUIDs). The Josephson junctions which form the basis of this technology can also be formed by introducing artificial barriers into the superconductor. The authors have examined both types of Josephson junctions by EM techniques in an effort to understand the connection between microstructure/chemistry and electrical transport properties. This knowledge is a valuable resource for the design and production of improved devices.

  9. Profit Neutrality in Licensing: The Boundary Between Antitrust Law and Patent Law

    E-Print Network [OSTI]

    Sadoulet, Elisabeth

    Profit Neutrality in Licensing: The Boundary Between Antitrust Law and Patent Law Stephen M. Maurer a century, courts and commentators have struggled to find principles that reconcile patent and antitrust law, especially as to patent licensing. We interpret case law and commentary to arrive at three unifying

  10. On a Linear Programming Approach to the Discrete Willmore Boundary Value Problem

    E-Print Network [OSTI]

    Cremers, Daniel

    involving pairs of elementary triangles chosen in a pre-specified dictionary and allowing self The Willmore energy of an immersed compact oriented surface f : RN with boundary is defined as W(f) = |H|2 concrete optimization problems where the Willmore functional ap- pears, let us mention for instance

  11. On a linear programming approach to the discrete Willmore boundary value problem and

    E-Print Network [OSTI]

    Lunds Universitet

    - mulation involving pairs of elementary triangles chosen in a pre-specified dictionary and allowing self compact oriented surface f : RN with boundary is defined as W(f) = |H|2 dA + ds where H is the mean membranes theory, strings theory, and image processing. Among the many concrete optimization problems where

  12. Integrated Simulations for Multi-Component Analysis of Gas Turbines : RANS Boundary Conditions

    E-Print Network [OSTI]

    Kim, Sangho

    More recently the coupling method has also been applied to a Pratt & Whitney gas turbine.7 The RANSIntegrated Simulations for Multi-Component Analysis of Gas Turbines : RANS Boundary Conditions 94305, U.S.A The aero-thermal computation of the flow path of an entire gas turbine engine can

  13. ESTIMATING BEDROCK AND SURFACE LAYER BOUNDARIES AND CONFIDENCE INTERVALS IN ICE SHEET RADAR IMAGERY USING MCMC

    E-Print Network [OSTI]

    Menczer, Filippo

    ESTIMATING BEDROCK AND SURFACE LAYER BOUNDARIES AND CONFIDENCE INTERVALS IN ICE SHEET RADAR IMAGERY and Computing Indiana University Bloomington, Indiana USA ABSTRACT Climate models that predict polar ice sheet behavior require accurate measurements of the bedrock-ice and ice-air bound- aries in ground

  14. HOW TO DISPATCH OBSERVERS TO TRACK AN EVOLVING BOUNDARY Tingting Jiang and Carlo Tomasi

    E-Print Network [OSTI]

    Tomasi, Carlo

    boundary of a large phenomenon such as an oil spill, a fire, a hurricane, air or water pollution, or EL Ni it necessary to dispatch a limited number of observers (ships, vehicles, or air- planes with cameras; field~no. This pa- per develops a new framework for controlling the movements of the observers to maximize

  15. Blockage of natural convection boundary layer flow in a multizone enclosure

    SciTech Connect (OSTI)

    Scott, D.; Anderson, R.; Figliola, R.S.

    1986-02-01T23:59:59.000Z

    This paper reports the results of an experimental study that examines the transition between flow regimes, as a function of aperture size, in a two-zone enclosure with heated and cooled end walls. A constant heat flux boundary condition was maintained on one vertical end wall, and an isothermal cold temperature sink was maintained on the opposite vertical end wall. All of the remaining surfaces were highly insulated. The transition between the boundary layer driven regime and the bulk density driven regime was established as a function of the geometry of the aperture in the partition that separated the hot and cold zones. The results demonstrate that transition from the boundary layer driven regime to the bulk density driven regime is caused by blockage of the boundary layer flow, when the area of the flow aperture is reduced below a critical value. A simple flow model has been developed which predicts that the critical aperture area for the onset of flow blockage is directly proportional to the number of active heat transfer surfaces and inversely proportional to the Rayleigh number which characterizes the level of heating and cooling provided to the active heat transfer surfaces.

  16. Control of the ocean circulation by boundaries and topography P.B. Rhines

    E-Print Network [OSTI]

    Seattle, Washington 98105 rhines@uw.edu 2 June 2011 1 #12;ABSTRACT The kinetic energy in the ocean baroclinic Rossby waves) dominate the surface kinetic energy of the world ocean, and their westward marchControl of the ocean circulation by boundaries and topography P.B. Rhines University of Washington

  17. Shock-like structures in the tropical cyclone boundary layer Gabriel J. Williams,1

    E-Print Network [OSTI]

    Schubert, Wayne H.

    the horizontal and vertical velocity data shown by the blue curves in Figure 1. The extreme horizontal wind m in the northeast sector. Since these extreme structures in the boundary layer wind field occur produces a shock-like structure in the radial wind, i.e., near the radius of maximum tangential wind

  18. Impact of boundaries on velocity profiles in bubble rafts Yuhong Wang, Kapilanjan Krishan, and Michael Dennin

    E-Print Network [OSTI]

    Dennin, Michael

    92697-4575 (Dated: November 7, 2005) Under conditions of sufficiently slow flow, foams, colloids, and an important issue in these systems is the role of the confining boundaries. For foams, three basic systems); and confined bubble rafts (bubbles confined between the surface of water below and a glass plate on top). Often

  19. Magnetostratigraphy of Permian/Triassic boundary sequences in the Cis-Urals, Russia: No evidence for a major temporal hiatus

    E-Print Network [OSTI]

    Benton, Michael

    Magnetostratigraphy of Permian/Triassic boundary sequences in the Cis-Urals, Russia: No evidence, Astrakhanskaya 83, 410075 Saratov, Russia a b s t r a c ta r t i c l e i n f o Article history: Received 6 June Editor: R.D. van der Hilst Keywords: Magnetostratigraphy Permian­Triassic boundary Russia Tatarian During

  20. Boundary-Layer Meteorol (2009) 132:129149 DOI 10.1007/s10546-009-9380-8

    E-Print Network [OSTI]

    Porté-Agel, Fernando

    2009-01-01T23:59:59.000Z

    -Tunnel Investigation of Wind-Turbine Wakes: Boundary-Layer Turbulence Effects Leonardo P. Chamorro · Fernando Porté to study turbulence in the wake of a model wind turbine placed in a boundary layer developed over rough effects · Turbulence · Wake structure · Wind-tunnel experiment · Wind turbine L. P. Chamorro · F. Porté

  1. Interfaces and Free Boundaries 5 (2003), 183192 On the geometry of HeleShaw flows with small surface tension

    E-Print Network [OSTI]

    Markina, Irina

    surface tension ALEXANDER VASIL'EV AND IRINA MARKINA Departamento de Matem´atica, Universidad T January 2003] We study the time evolution of the free boundary of a viscous fluid in the non-zero-surface-tension. Keywords: Free boundary problem; Hele­Shaw flow; surface tension; conformal map. 2000 Mathematics Subject

  2. Computation of hypersonic shock boundary layer interaction on a double wedge using a differential Reynolds Stress Model

    E-Print Network [OSTI]

    Computation of hypersonic shock boundary layer interaction on a double wedge using a differential The simulation of hypersonic flows presents some difficulties due to the interaction between boundary layers on the standard test case of a subsonic flat plate and on a hypersonic configuration. The results show a good

  3. An extended organic carbon-isotope record across the TriassicJurassic boundary in the Queen Charlotte Islands,

    E-Print Network [OSTI]

    Williford, Kenneth H.

    a negative offset in baseline carbon isotope values from approximately -29 in the Late Norian to -31An extended organic carbon-isotope record across the Triassic­Jurassic boundary in the Queen carbon-isotope data are presented for the Triassic­Jurassic boundary section at Kennecott Point, Queen

  4. MOSSBAUER STUDIES ON THE STATE OF TIN ATOMS SEGREGATED AT THE GRAIN BOUNDARY OF IRON AND IRON ALLOYS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    MOSSBAUER STUDIES ON THE STATE OF TIN ATOMS SEGREGATED AT THE GRAIN BOUNDARY OF IRON AND IRON, Tokyo, Japan Abstract.- The binding state of tin atoms segregated at the grain boundary of fine grained state differs considerably from that of solid solution tin even though the average binding force itself

  5. Internal wave and boundary current generation by tidal flow over topography Amadeus Dettner, Harry L. Swinney, and M. S. Paoletti

    E-Print Network [OSTI]

    Texas at Austin. University of

    .1063/1.4808163 Negative turbulent production during flow reversal in a stratified oscillating boundary layer on a sloping of Texas at Austin, Austin, Texas 78712, USA (Received 31 May 2013; accepted 10 October 2013; published of a uniformly stratified fluid. The radiated power PIW and kinetic energy density of the boundary currents

  6. Well conditioned boundary integral equations for two-dimensional sound-hard scattering problems in domains with corners

    E-Print Network [OSTI]

    Turc, Catalin

    Well conditioned boundary integral equations for two-dimensional sound-hard scattering problems-posed, well conditioned integral equation formulations for the solution of two-dimensional acoustic scattering-order, rapidly convergent numerical methods based on well-conditioned boundary integral equations for the case

  7. Accumulation mode aerosol, pockets of open cells, and particle nucleation in the remote subtropical Pacific marine boundary layer

    E-Print Network [OSTI]

    Russell, Lynn

    Accumulation mode aerosol, pockets of open cells, and particle nucleation in the remote subtropical in the remote subtropical Pacific marine boundary layer, J. Geophys. Res., 111, D02206, doi:10.1029/2004JD005694 the boundary layer via its action on the budgets of heat and water substance. A plausible consequence may

  8. Evaluating the Performance of Planetary Boundary Layer and Cloud Microphysical Parameterization Schemes in Convection-Permitting Ensemble Forecasts using

    E-Print Network [OSTI]

    Xue, Ming

    uncertainty in how to include various processes (e.g., drop breakup and ice-phase categories 1 Evaluating the Performance of Planetary Boundary Layer and Cloud Microphysical Parameterization In this study, the ability of several cloud microphysical and planetary boundary layer parameterization schemes

  9. Second order adaptive boundary conditions for exterior flow problems: non-symmetric stationary flows in two dimensions

    E-Print Network [OSTI]

    called "artificial boundary conditions" to replace the boundary conditions at infinity. To solve this problem we construct -- by combining results from dynamical systems theory with matched asymptotic field depending explicitly on drag and lift and describing the solution to second and dominant third

  10. The relative grain boundary area and energy distributions in a ferritic steel determined from three-dimensional electron

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    The relative grain boundary area and energy distributions in a ferritic steel determined from three The relative grain boundary area and energy distributions of a ferritic steel were characterized as a function planes with the (111) orientation had the minimum energy and the largest relative areas. The most

  11. Concentration profiles across twin boundaries in YBa{sub 2}Cu{sub 3}O{sub 6+{delta}}

    SciTech Connect (OSTI)

    Hu, Q.; Stiller, K.; Olsson, E.; Andren, H. [Department of Physics, Chalmers University of Technology and University of Goeteborg, S-412 96 Goeteborg (Sweden)] [Department of Physics, Chalmers University of Technology and University of Goeteborg, S-412 96 Goeteborg (Sweden); Berastegui, P.; Johansson, L. [Department of Inorganic Chemistry, Chalmers University of Technology and University of Goeteborg, S-412 96 Goeteborg (Sweden)] [Department of Inorganic Chemistry, Chalmers University of Technology and University of Goeteborg, S-412 96 Goeteborg (Sweden)

    1997-11-01T23:59:59.000Z

    Twin boundaries in polycrystalline YBa{sub 2}Cu{sub 3}O{sub 6+{delta}} have been studied by atom-probe field-ion microscopy. Oxygen depletion at a twin boundary in a {delta}=0.6 material was observed. The width of the depleted region was 6{endash}7 nm. It agrees well with the width of oxygen depletion calculated from the oxygen-depleted twin boundary model by Jou and Washburn. However, a twin boundary in a {delta}=0.9 material did not show any oxygen depletion. This study provides direct evidence of oxygen depletion at twin boundaries in polycrystalline YBa{sub 2}Cu{sub 3}O{sub 6+{delta}} ceramics. {copyright} {ital 1997} {ital The American Physical Society}

  12. Multiscale Modeling of Grain Boundary Segregation and Embrittlement in Tungsten for Mechanistic Design of Alloys for Coal Fired Plants

    SciTech Connect (OSTI)

    Luo, Jian; Tomar, Vikas; Zhou, Naixie; Lee, Hongsuk

    2013-06-30T23:59:59.000Z

    Based on a recent discovery of premelting-like grain boundary segregation in refractory metals occurring at high temperatures and/or high alloying levels, this project investigated grain boundary segregation and embrittlement in tungsten (W) based alloys. Specifically, new interfacial thermodynamic models have been developed and quantified to predict high-temperature grain boundary segregation in the W-Ni binary alloy and W-Ni-Fe, W-Ni-Ti, W-Ni-Co, W-Ni-Cr, W-Ni-Zr and W-Ni-Nb ternary alloys. The thermodynamic modeling results have been experimentally validated for selected systems. Furthermore, multiscale modeling has been conducted at continuum, atomistic and quantum-mechanical levels to link grain boundary segregation with embrittlement. In summary, this 3-year project has successfully developed a theoretical framework in combination with a multiscale modeling strategy for predicting grain boundary segregation and embrittlement in W based alloys.

  13. The Formation of Boundary Clinopyroxenes and Associated Glass Veins in Type B1 CAIs

    SciTech Connect (OSTI)

    Paque, J M; Beckett, J R; Ishii, H A; Toppani, A; Burnett, D S; Teslich, N; Dai, Z R; Bradley, J P

    2008-05-18T23:59:59.000Z

    We used focused ion beam thin section preparation and scanning transmission electron microscopy (FIB/STEM) to examine the interfacial region between spinel and host melilite for three spinel grains, two from the mantle and one from the core of an Allende type B1 inclusion, and a second pair of spinel grains from a type B1 inclusion from the Leoville carbonaceous chondrite. The compositions of boundary clinopyroxenes decorating spinel surfaces are generally consistent with those of coarser clinopyroxenes from the same region of the inclusion, suggesting little movement of spinels between mantle and core regions after the formation of boundary clinopyroxenes. The host melilite displays no anomalous compositions near the interface, and anorthite or other late-stage minerals are not observed, suggesting that crystallization of residual liquid was not responsible for the formation of boundary clinopyroxenes. Allende spinels display either direct spinel-melilite contact or an intervening boundary clinopyroxene between the two phases. In the core, boundary clinopyroxene is mantled by a thin (1-2 {micro}m thick) layer of normally zoned (X{sub Ak} increasing away from the melilite-clinopyroxene contact) melilite with X{sub Ak} matching that of the host melilite at the melilite-melilite contact. In the mantle, X{sub Ak} near boundary spinels is constant. Spinels in a Leoville type B1 inclusion are more complex with boundary clinopyroxene, as observed in Allende, but also variable amounts of glass ({approx}1 {micro}m width), secondary calcite, perovskite, and an unknown Mg-, Al-, OH-rich and Ca-, Si-poor crystalline phase that may be a layered double hydrate. Glass compositions are consistent to first order with a precursor consisting mostly of Mg-carpholite or sudoite with some aluminous diopside. One possible scenario of formation for the glass veins is that open system alteration of melilite produced a porous, hydrated aggregate of Mg-carpholite or sudoite + aluminous diopside that was shock melted and quenched to a glass. The unknown crystalline phase may be a shocked remnant of the precursor phase assemblage but is more likely to have formed later by alteration of the glass. Calcite appears to be an opportunistic fracture filling that postdated all major shock events. Boundary clinopyroxenes probably share a common origin with coarser-grained pyroxenes from the same region of the inclusion. In the mantle, these crystals may represent clinopyroxene crystallized in Ti-rich liquids caused by the direct dissolution of perovskite and an associated Sc-Zr-rich phase or as a reaction product between dissolving perovskite and liquid (i.e., indirect dissolution of perovskite). In the core, any perovskite and associated Ti-enriched liquids that may have originally been present disappeared before the growth of boundary clinopyroxene.

  14. Binding energetics of substitutional and interstitial helium and di-helium defects with grain boundary structure in ?-Fe

    SciTech Connect (OSTI)

    Tschopp, M. A., E-mail: mark.tschopp@gatech.edu [Dynamic Research Corporation, (on site at) U.S. Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005 (United States); Center for Advanced Vehicular Systems, Mississippi State University, Starkville, Mississippi 39762 (United States); Gao, F.; Yang, L. [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Solanki, K. N. [Arizona State University, School for Engineering of Matter, Transport and Energy, Tempe, Arizona 85287 (United States)

    2014-01-21T23:59:59.000Z

    The formation/binding energetics and length scales associated with the interaction between He atoms and grain boundaries in BCC ?-Fe were explored. Ten different low ? grain boundaries from the ?100? and ?110? symmetric tilt grain boundary systems were used. In this work, we then calculated formation/binding energies for 1–2 He atoms in the substitutional and interstitial sites (HeV, He{sub 2}V, HeInt, He{sub 2}Int) at all potential grain boundary sites within 15?Å of the boundary (52?826 simulations total). The present results provide detailed information about the interaction energies and length scales of 1–2 He atoms with grain boundaries for the structures examined. A number of interesting new findings emerge from the present study. For instance, the ?3(112) twin boundary in BCC Fe possesses a much smaller binding energy than other boundaries, which corresponds in long time dynamics simulations to the ability of an interstitial He defect to break away from the boundary in simulations on the order of nanoseconds. Additionally, positive correlations between the calculated formation/binding energies of the He defects (R?>?0.9) asserts that the local environment surrounding each site strongly influences the He defect energies and that highly accurate quantum mechanics calculations of lower order defects may be an adequate predictor of higher order defects. Various metrics to quantify or classify the local environment were compared with the He defect binding energies. The present work shows that the binding and formation energies for He defects are important for understanding the physics of He diffusion and trapping by grain boundaries, which can be important for modeling He interactions in polycrystalline steels.

  15. Boundary Layer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sea spray generation is determined by a source function that depends on background wind speed. Non-local mixing of the HBL caused by LE leads to the formation of a well-mixed HBL...

  16. "Non-Reflective" Boundary Design via Remote Sensing and PID Control Valve

    SciTech Connect (OSTI)

    Zhang, Qin Fen [ORNL] [ORNL; Karney, Professor Byran W. [University of Toronto, Canada] [University of Toronto, Canada; Pejovic, Dr. Stanislav [University of Toronto, Canada] [University of Toronto, Canada

    2011-01-01T23:59:59.000Z

    This paper develops the concept of a nonreflective (or semireflective) boundary condition using the combination of a remote sensor and a control system to modulate a relief valve. The essential idea is to sense the pressure change at a remote location and then to use the measured data to adjust the opening of an active control valve at the end of the line to eliminate or attenuate the wave reflections at the valve, thus controlling system transient pressures. This novel idea is shown here through numerical simulation to have considerable potential for transient protection. Using this model, wave reflections and resonance can be effectively eliminated for frictionless pipelines or initial no-flow conditions and can be better controlled in more realistic pipelines for a range of transient disturbances. In addition, the features of even-order harmonics and nonreflective boundary conditions during steady oscillation, obtained through time domain transient analysis, are verified by hydraulic impedance analysis in the frequency domain.

  17. Nonequilibrium transport through quantum-wire junctions and boundary defects for free massless bosonic fields

    E-Print Network [OSTI]

    Gaw?dzki, Krzysztof

    2015-01-01T23:59:59.000Z

    We consider a model of quantum-wire junctions where the latter are described by conformal-invariant boundary conditions of the simplest type in the multicomponent compactified massless scalar free field theory representing the bosonized Luttinger liquids in the bulk of wires. The boundary conditions result in the scattering of charges across the junction with nontrivial reflection and transmission amplitudes. The equilibrium state of such a system, corresponding to inverse temperature $\\beta$ and electric potential $V$, is explicitly constructed both for finite and for semi-infinite wires. In the latter case, a stationary nonequilibrium state describing the wires kept at different temperatures and potentials may be also constructed. The main result of the present paper is the calculation of the full counting statistics (FCS) of the charge and energy transfers through the junction in a nonequilibrium situation. Explicit expressions are worked out for the generating function of FCS and its large-deviations asym...

  18. Experimental investigation of sound generation by a protuberance in a laminar boundary layer

    SciTech Connect (OSTI)

    Kobayashi, M.; Asai, M.; Inasawa, A. [Department of Aerospace Engineering, Tokyo Metropolitan University, 6-6 Asahigaoka, Hino, Tokyo 191-0065 (Japan)

    2014-08-15T23:59:59.000Z

    Sound radiation from a two-dimensional protuberance glued on the wall in a laminar boundary layer was investigated experimentally at low Mach numbers. When the protuberance was as high as the boundary-layer thickness, a feedback-loop mechanism set in between protuberance-generated sound and Tollmien-Schlichting (T-S) waves generated by the leading-edge receptivity to the upstream-propagating sound. Although occurrence of a separation bubble immediately upstream of the protuberance played important roles in the evolution of instability waves into vortices interacting with the protuberance, the frequency of tonal vortex sound was determined by the selective amplification of T-S waves in the linear instability stage upstream of the separation bubble and was not affected by the instability of the separation bubble.

  19. A survey of repair practices for nuclear power plant containment metallic pressure boundaries

    SciTech Connect (OSTI)

    Oland, C.B.; Naus, D.J. [Oak Ridge National Lab., TN (United States)

    1998-05-01T23:59:59.000Z

    The Nuclear Regulatory Commission has initiated a program at the Oak Ridge National Laboratory to provide assistance in their assessment of the effects of potential degradation on the structural integrity and leaktightness of metal containment vessels and steel liners of concrete containments in nuclear power plants. One of the program objectives is to identify repair practices for restoring metallic containment pressure boundary components that have been damaged or degraded in service. This report presents issues associated with inservice condition assessments and continued service evaluations and identifies the rules and requirements for the repair and replacement of nonconforming containment pressure boundary components by welding or metal removal. Discussion topics include base and welding materials, welding procedure and performance qualifications, inspection techniques, testing methods, acceptance criteria, and documentation requirements necessary for making acceptable repairs and replacements so that the plant can be returned to a safe operating condition.

  20. Mixing in thermally stratified nonlinear spin-up with uniform boundary fluxes

    SciTech Connect (OSTI)

    Baghdasarian, Meline; Pacheco-Vega, Arturo [Department of Mechanical Engineering, California State University, Los Angeles, Los Angeles, California 90032 (United States); Pacheco, J. Rafael, E-mail: rpacheco@asu.edu [SAP Americas Inc., Scottsdale, Arizona 85251 (United States); School of Mathematical and Statistical Sciences, Arizona State University, Tempe, Arizona 85287 (United States); Environmental Fluid Dynamics Laboratories, Department of Civil Engineering and Geological Sciences, The University of Notre Dame, South Bend, Indiana 46556 (United States); Verzicco, Roberto [Dipartimento di Ingegneria Meccanica, Universita di Roma “Tor Vergata”, Via del Politecnico 1, 00133, Roma (Italy); PoF, University of Twente, 7500 AE Enschede (Netherlands)

    2014-09-15T23:59:59.000Z

    Studies of stratified spin-up experiments in enclosed cylinders have reported the presence of small pockets of well-mixed fluids but quantitative measurements of the mixedness of the fluid has been lacking. Previous numerical simulations have not addressed these measurements. Here we present numerical simulations that explain how the combined effect of spin-up and thermal boundary conditions enhances or hinders mixing of a fluid in a cylinder. The energy of the system is characterized by splitting the potential energy into diabatic and adiabatic components, and measurements of efficiency of mixing are based on both, the ratio of dissipation of available potential energy to forcing and variance of temperature. The numerical simulations of the Navier–Stokes equations for the problem with different sets of thermal boundary conditions at the horizontal walls helped shed some light on the physical mechanisms of mixing, for which a clear explanation was absent.