Sample records for video disc players

  1. Computer animation via optical video disc

    E-Print Network [OSTI]

    Bender, Walter

    1981-01-01T23:59:59.000Z

    This paper explores the notion of marrying two technologies: raster-scan computer animation and optical video discs. Animated sequences, generated at non real-time rates, then transfered to video disc, can be recalled under ...

  2. Cowboys, pop stars, pimps and players: themes in music videos

    E-Print Network [OSTI]

    Wesley, Chelcie Melissa

    2005-08-29T23:59:59.000Z

    Television is something that is a part of the everyday lives of a majority of people in America. The content of what is on television can vary in nature from being positive to being negative. However, what people are exposed to through music videos...

  3. Identification and Tracking of Players in Sports Videos Chun-Wei Lu, Chao-Yung Hsu, and Hong-Yuan Mark Liao

    E-Print Network [OSTI]

    Chen, Sheng-Wei

    Project Identification and Tracking of Players in Sports Videos Chun-Wei Lu, Chao-Yung Hsu, and Hong-Yuan Mark Liao Challenges To develop an automatic basketball video analysis system is difficult motions and may move outside the field of view of the camera . Most existing basketball video analysis

  4. australian football players: Topics by E-print Network

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

    Summary: Modality Specific Assessment of Video Game Player's Cognitive Workload Using Off Denton, Texas, USA April 2014 12;Assessment of Video Game Cognitive Workload 1 Running...

  5. american football players: Topics by E-print Network

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

    Summary: Modality Specific Assessment of Video Game Player's Cognitive Workload Using Off Denton, Texas, USA April 2014 12;Assessment of Video Game Cognitive Workload 1 Running...

  6. A Media Player for Use in Distance Education

    E-Print Network [OSTI]

    Huang, Kai

    We have developed a media player for use in distance education. The player can incorporate several time-indexed sources, including video, audio, PowerPoint, and text index. We have converted all the SMA 5503 Introduction ...

  7. Videos

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1 - USAFofEmail Mr. WilliamVideo: Watch the

  8. Videos

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize AvailableMedia Room / Photobrown-bag-videos

  9. Video Digests: A Browsable, Skimmable Format for Informational Lecture Videos

    E-Print Network [OSTI]

    O'Brien, James F.

    Video Digests: A Browsable, Skimmable Format for Informational Lecture Videos Amy Pavel, Colorado- ing current timeline-based video players. Video digests are a new format for informational videos authors create such digests using transcript-based interactions. With our tools, authors can manually

  10. Webinar: Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique

    Broader source: Energy.gov [DOE]

    Video recording of the Fuel Cell Technologies Office webinar, Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique, originally presented on March 12, 2013.

  11. Deep Web Video, Office of Scientific and Technical Information...

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

    Deep Web Video Download latest version of Flash Player exit federal site to view Video. The U.S. Department of Energy (DOE) Office of Scientific and Technical Information (OSTI)...

  12. Thin discs, thick discs and transition zones

    E-Print Network [OSTI]

    Guillaume Dubus

    2002-06-13T23:59:59.000Z

    Accretion onto a compact object must occur through a disc when the material has some initial angular momentum. Thin discs and the thicker low radiative efficiency accretion flows are solutions to this problem that have been widely studied and applied. This is an introduction to these accretion flows within the context of X-ray binaries and cataclysmic variables.

  13. FEATURE BASED HANDLING OF SURFACE FAULTS IN COMPACT DISC PLAYERS

    E-Print Network [OSTI]

    Wickerhauser, M. Victor

    two photo detectors. The distances are the distance from the actual position of the OPU such surface faults. The core idea is not to rely on sensor information during the fault. The sensor signals

  14. Turbulent protostellar discs

    E-Print Network [OSTI]

    Axel Brandenburg

    2008-08-07T23:59:59.000Z

    Aspects of turbulence in protostellar accretion discs are being reviewed. The emergence of dead zones due to poor ionization and alternatives to the magneto-rotational instability are discussed. The coupling between dust and gas in protostellar accretion discs is explained and turbulent drag is compared with laminar drag in the Stokes and Epstein regimes. Finally, the significance of magnetic field generation in turbulent discs is emphasized in connection with driving outflows and with star-disc coupling.

  15. Turbine disc sealing assembly

    DOE Patents [OSTI]

    Diakunchak, Ihor S.

    2013-03-05T23:59:59.000Z

    A disc seal assembly for use in a turbine engine. The disc seal assembly includes a plurality of outwardly extending sealing flange members that define a plurality of fluid pockets. The sealing flange members define a labyrinth flow path therebetween to limit leakage between a hot gas path and a disc cavity in the turbine engine.

  16. RHIC Videos

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

    Laboratory search U.S. Department of Energy logo Home RHIC Science News Images Videos For Scientists RHIC Videos Other Videos 455 Science Friday Science Friday Explains...

  17. Black hole accretion discs

    E-Print Network [OSTI]

    Lasota, Jean-Pierre

    2015-01-01T23:59:59.000Z

    This is an introduction to models of accretion discs around black holes. After a presentation of the non-relativistic equations describing the structure and evolution of geometrically thin accretion discs we discuss their steady-state solutions and compare them to observation. Next we describe in detail the thermal-viscous disc instability model and its application to dwarf novae for which it was designed and its X-ray irradiated-disc version which explains the soft X--ray transients, i.e. outbursting black-hole low-mass X-ray binaries. We then turn to the role of advection in accretion flow onto black holes illustrating its action and importance with a toy model describing both ADAFs and slim discs. We conclude with a presentation of the general-relativistic formalism describing accretion discs in the Kerr space-time.

  18. Disc-Disc Encounters between Low-Mass Protoplanetary Accretion Discs

    E-Print Network [OSTI]

    S. Pfalzner; S. Umbreit; Th. Henning

    2005-04-27T23:59:59.000Z

    Simulations of the collapse and fragmentation of turbulent molecular clouds and dense young clusters show that encounters between disc-surrounded stars are relatively common events which should significantly influence the resulting disc structure. In turn this should alter the accretion rate of disc matter onto the star and the conditions under which planet formation occurs. Although the effects of star-disc encounters have been previously investigated, very little is known about encounters where both stars are surrounded by discs. In this paper encounters of such disc-disc systems are studied quantitatively. It is found that for low-mass discs ($M_D$= 0.01 $M_\\sun$) the results from star-disc encounters can be straightforwardly generalized to disc-disc encounters as long as there is no mass transport between the discs. Differences to star-disc encounters occur naturally where significant amounts of matter are transported between the discs. In this case it is found that although the mass distribution does not change significantly, matter caught onto highly eccentric orbits is transported surprisingly far inside the disc. The captured mass partly replenishes the disc, but has a much lower angular momentum. This can lead to a reduction of the angular momentum in the entire disc and thus considerably increased accretion shortly after the encounter as well as in the long term.

  19. Learning Transformations From Video

    E-Print Network [OSTI]

    Wang, Ching Ming

    2010-01-01T23:59:59.000Z

    on Natural Video . . . . . . . . . . . . . . . . .3 Learning Continuous Transformation from VideoProposed Video Coder

  20. Crowdsourcing step-by-step information extraction to enhance existing how-to videos

    E-Print Network [OSTI]

    Nguyen, Phu Tran

    Millions of learners today use how-to videos to master new skills in a variety of domains. But browsing such videos is often tedious and inefficient because video player interfaces are not optimized for the unique step-by-step ...

  1. Radiation from Dwarf Nova Discs

    E-Print Network [OSTI]

    Irit Idan; Jean-Pierre Lasota; Jean-Marie Hameury; Giora Shaviv

    1998-06-04T23:59:59.000Z

    We use the Shaviv and Wehrse (1991) code to model the vertical structure and the emission properties of quiescent dwarf nova discs. We find that in the case of HT Cas the quiescent disc must be optically thin, in contradiction with the requirements of the standard disc instability model. We find a viscosity parameter alpha > 1. Although this is much less than values (~ 100) obtained in isothermal slab models it is not consistent with the accretion disc model assumptions.

  2. Self-gravitating accretion discs

    E-Print Network [OSTI]

    G. Lodato

    2008-01-25T23:59:59.000Z

    I review recent progresses in the dynamics and the evolution of self-gravitating accretion discs. Accretion discs are a fundamental component of several astrophysical systems on very diverse scales, and can be found around supermassive black holes in Active Galactic Nuclei (AGN), and also in our Galaxy around stellar mass compact objects and around young stars. Notwithstanding the specific differences arising from such diversity in physical extent, all these systems share a common feature where a central object is fed from the accretion disc, due to the effect of turbulence and disc instabilities, which are able to remove the angular momentum from the gas and allow its accretion. In recent years, it has become increasingly apparent that the gravitational field produced by the disc itself (the disc's self-gravity) is an important ingredient in the models, especially in the context of protostellar discs and of AGN discs. Indeed, it appears that in many cases (and especially in the colder outer parts of the disc) the development of gravitational instabilities can be one of the main agents in the redistribution of angular momentum. In some cases, the instability can be strong enough to lead to the formation of gravitationally bound clumps within the disc, and thus to determine the disc fragmentation. As a result, progress in our understanding of the dynamics of self-gravitating discs is essential to understand the processes that lead to the feeding of both young stars and of supermassive black holes in AGN. At the same time, understanding the fragmentation conditions is important to determine under which conditions AGN discs would fragment and form stars and whether protostellar discs might form giant gaseous planets through disc fragmentation.

  3. Warp propagation in astrophysical discs

    E-Print Network [OSTI]

    Nixon, Chris

    2015-01-01T23:59:59.000Z

    Astrophysical discs are often warped, that is, their orbital planes change with radius. This occurs whenever there is a non-axisymmetric force acting on the disc, for example the Lense-Thirring precession induced by a misaligned spinning black hole, or the gravitational pull of a misaligned companion. Such misalignments appear to be generic in astrophysics. The wide range of systems that can harbour warped discs - protostars, X-ray binaries, tidal disruption events, quasars and others - allows for a rich variety in the disc's response. Here we review the basic physics of warped discs and its implications.

  4. V-090: Adobe Flash Player / AIR Multiple Vulnerabilities | Department...

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

    0: Adobe Flash Player AIR Multiple Vulnerabilities V-090: Adobe Flash Player AIR Multiple Vulnerabilities February 13, 2013 - 12:14am Addthis PROBLEM: Adobe Flash Player AIR...

  5. Non-Cooperative Facial Recognition Video Dataset Collection Plan

    SciTech Connect (OSTI)

    Kimura, Marcia L.; Erikson, Rebecca L.; Lombardo, Nicholas J.

    2013-08-31T23:59:59.000Z

    The Pacific Northwest National Laboratory (PNNL) will produce a non-cooperative (i.e. not posing for the camera) facial recognition video data set for research purposes to evaluate and enhance facial recognition systems technology. The aggregate data set consists of 1) videos capturing PNNL role players and public volunteers in three key operational settings, 2) photographs of the role players for enrolling in an evaluation database, and 3) ground truth data that documents when the role player is within various camera fields of view. PNNL will deliver the aggregate data set to DHS who may then choose to make it available to other government agencies interested in evaluating and enhancing facial recognition systems. The three operational settings that will be the focus of the video collection effort include: 1) unidirectional crowd flow 2) bi-directional crowd flow, and 3) linear and/or serpentine queues.

  6. Enclosed rotary disc air pulser

    DOE Patents [OSTI]

    Olson, A. L. (Idaho Falls, ID); Batcheller, Tom A. (Idaho Falls, ID); Rindfleisch, J. A. (Arco, ID); Morgan, John M. (Arco, ID)

    1989-01-01T23:59:59.000Z

    An enclosed rotary disc air pulser for use with a solvent extraction pulse olumn includes a housing having inlet, exhaust and pulse leg ports, a shaft mounted in the housing and adapted for axial rotation therein, first and second disc members secured to the shaft within the housing in spaced relation to each other to define a chamber therebetween, the chamber being in communication with the pulse leg port, the first disc member located adjacent the inlet port, the second disc member being located adjacent the exhaust port, each disc member having a milled out portion, the disc members positioned on the shaft so that as the shaft rotates, the milled out portions permit alternative cyclical communication between the inlet port and the chamber and the exhaust port and the chamber.

  7. The "top player problem" Here are two solutions of the "top player" problem,

    E-Print Network [OSTI]

    Sussmann, Hector

    The "top player problem" Here are two solutions of the "top player" problem, IMPORTANT REMARK that every tournament has a top player. For this purpose, it suffices to prove that (*) For every natural number n, and every tournament t with n play- ers, t has a top player. (If we use T(t) for "t

  8. SimProjectTM Player's Manual

    E-Print Network [OSTI]

    Rudowsky, Ira

    SimProjectTM Player's Manual i SIMPROJECTTMA Project Management Simulation for Classroom variables that are routinely encountered in project management and decision making. Best and most important Instruction PLAYER'S MANUAL V 1.2 JEFFREY K. PINTO, PH.D. AND DIANE H. PARENTE, PH.D. Player's Manual for use

  9. Volume One Disc Two

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1 -Visualizing Brain Metals inVolume-One-Disc-Two

  10. Video Production For Short Educational Videos

    E-Print Network [OSTI]

    Video Production Handbook For Short Educational Videos Jennifer Cook Small Acreage Management page 6 Introduction page 3 Prepare for Video Shoot page 8 Video Shoot page 9 Editing Page 11 Draft Review page 12 Final Video page 13 Table of Contents Video Production Process #12;3 Equipment

  11. Gravitating discs around black holes

    E-Print Network [OSTI]

    V. Karas; J. -M. Hure; O. Semerak

    2004-01-16T23:59:59.000Z

    Fluid discs and tori around black holes are discussed within different approaches and with the emphasis on the role of disc gravity. First reviewed are the prospects of investigating the gravitational field of a black hole--disc system by analytical solutions of stationary, axially symmetric Einstein's equations. Then, more detailed considerations are focused to middle and outer parts of extended disc-like configurations where relativistic effects are small and the Newtonian description is adequate. Within general relativity, only a static case has been analysed in detail. Results are often very inspiring, however, simplifying assumptions must be imposed: ad hoc profiles of the disc density are commonly assumed and the effects of frame-dragging and completely lacking. Astrophysical discs (e.g. accretion discs in active galactic nuclei) typically extend far beyond the relativistic domain and are fairly diluted. However, self-gravity is still essential for their structure and evolution, as well as for their radiation emission and the impact on the environment around. For example, a nuclear star cluster in a galactic centre may bear various imprints of mutual star--disc interactions, which can be recognised in observational properties, such as the relation between the central mass and stellar velocity dispersion.

  12. Videos | EMSL

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

    Videos Current Search Search found 19 items By Year 2015 (3) Apply 2015 filter 2014 (14) Apply 2014 filter 2013 (2) Apply 2013 filter By Tags 21T magnet (1) Apply 21T magnet filter...

  13. Video dithering

    E-Print Network [OSTI]

    Yu, Jin Nah

    2004-09-30T23:59:59.000Z

    In this work, we present mathematical and artistic techniques for the easy creation of artistic screening animations in video resolution by extending the artistic screening technique of adapting various patterns as screen dots for generating...

  14. Video dithering 

    E-Print Network [OSTI]

    Yu, Jin Nah

    2004-09-30T23:59:59.000Z

    VIDEO DITHERING A Thesis by JIN NAH YU Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 2004... Major Subject: Visualization Sciences VIDEO DITHERING A Thesis by JIN NAH YU Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...

  15. Tidally-induced warps in protostellar discs

    E-Print Network [OSTI]

    C. Terquem; J. Papaloizou; R. Nelson

    1998-10-01T23:59:59.000Z

    We review results on the dynamics of warped gaseous discs. We consider tidal perturbation of a Keplerian disc by a companion star orbiting in a plane inclined to the disc. The perturbation induces the precession of the disc, and thus of any jet it could drive. In some conditions the precession rate is uniform, and as a result the disc settles into a warp mode. The tidal torque also leads to the truncation of the disc, to the evolution of the inclination angle (not necessarily towards alignment of the disc and orbital planes) and to a transport of angular momentum in the disc. We note that the spectral energy distribution of such a warped disc is different from that of a flat disc. We conclude by listing observational effects of warps in protostellar discs.

  16. Video Center Administrator Guide

    E-Print Network [OSTI]

    Eisen, Michael

    LifeSize® Video Center Administrator Guide March 2011 LifeSize Video Center 2200 #12;LifeSize Video Center Adminstrator Guide 2 Administering LifeSize Video Center LifeSize Video Center is a network server that stores and streams video sent by LifeSize video communications systems enabled for recording. It can also

  17. Video based system monitoring

    E-Print Network [OSTI]

    Anthony, Brian W., 1972-

    2006-01-01T23:59:59.000Z

    In this work we develop new algorithms for video comparison, for video alignment, and for determining the similarity between entire video clips or detecting similarities between sub-videos. The intent of this work is to ...

  18. Chess players' fame versus their merit

    E-Print Network [OSTI]

    Simkin, M V

    2015-01-01T23:59:59.000Z

    We investigate a pool of international chess title holders born between 1901 and 1943. Using Elo ratings we compute for every player his expected score in a game with a randomly selected player from the pool. We use this figure as player's merit. We measure players' fame as the number of Google hits. The correlation between fame and merit is 0.38. At the same time the correlation between the logarithm of fame and merit is 0.61. This suggests that fame grows exponentially with merit.

  19. V-176: Adobe Flash Player Memory Corruption Flaw Lets Remote...

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

    Adobe Flash Player Memory Corruption Flaw Lets Remote Users Execute Arbitrary Code PLATFORM: Adobe Flash Player 11.7.700.202 and earlier versions for Windows Adobe Flash Player...

  20. Kinematic Detection of the Galactic Nuclear Disc

    E-Print Network [OSTI]

    Schönrich, Ralph; Sale, Stuart E

    2015-01-01T23:59:59.000Z

    We report the detection of the Galactic nuclear disc in line-of-sight kinematics of stars, measured with infrared spectroscopy from APOGEE. The nuclear disc is found to have a rotation velocity V ~ 120km/s comparable to the gas disc. The current data suggest that this disc is kinematically quite cold and has a small vertical extent of order 50pc. The stellar kinematics suggest a truncation radius of the stellar disc at a galactocentric radius R ~ 150pc, and provide tentative evidence for an overdensity at the position of the ring found in the molecular gas disc.

  1. DISC-UK DataShare 

    E-Print Network [OSTI]

    Rice, Robin

    DISC-UK DataShare (http://www.disc-uk.org/datashare.html) is a JISC-funded collaborative project led by EDINA and Edinburgh University Data Library, with the Universities of Oxford and Southampton as partners, and the ...

  2. Physics and chemistry of gas in discs 

    E-Print Network [OSTI]

    Tilling, Ian

    2013-11-28T23:59:59.000Z

    Protoplanetary discs set the initial conditions for planet formation. By combining observations with detailed modelling, it is possible to constrain the physics and chemistry in such discs. I have used the detailed ...

  3. Thin, thick and dark discs in LCDM

    E-Print Network [OSTI]

    J. I. Read; G. Lake; O. Agertz; Victor P. Debattista

    2008-06-26T23:59:59.000Z

    In a LCDM cosmology, the Milky Way accretes satellites into the stellar disc. We use cosmological simulations to assess the frequency of near disc plane and higher inclination accretion events, and collisionless simulations of satellite mergers to quantify the final state of the accreted material and the effect on the thin disc. On average, a Milky Way-sized galaxy has 3 subhalos with vmax>80km/s; 7 with vmax>60km/s; and 15 with vmax>40km/s merge at redshift z>1. Assuming isotropic accretion, a third of these merge at an impact angle disc plane by dynamical friction. Their accreted stars and dark matter settle into a thick disc. The stellar thick disc qualitatively reproduces the observed thick disc at the solar neighbourhood, but is less massive by a factor ~2-10. The dark matter disc contributes 0.25-1 times the halo density at the solar position. Although not likely to be dynamically interesting, the dark disc has important implications for the direct detection of dark matter because of its low velocity with respect to the Earth. Higher inclination encounters (>20 degrees) are twice as likely as low inclination ones. These lead to structures that closely resemble the recently discovered inner/outer stellar halos. They also do more damage to the Milky Way stellar disc creating a more pronounced flare, and warp; both long-lived and consistent with current observations. The most massive mergers (vmax>80km/s) heat the thin disc enough to produce a thick disc. These heated thin disc stars are essential for obtaining a thick disc as massive as that seen in the Milky Way; they likely comprise some ~50-90% of the thick disc stars. The Milky Way thin disc must reform from fresh gas after z=1 [abridged].

  4. Video Gallery

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1 - USAFofEmail Mr. William HirstVictor F.Video

  5. Stewardship Videos

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary900Steep Slope CalculatorSteveStewardship Videos Stewardship

  6. Sandia National Laboratories: Videos

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

    Videos NASA Earth at Night Video On January 9, 2013, in EC, Energy, Energy Efficiency, Global, Modeling, News & Events, Solid-State Lighting, Videos Have you ever wondered what the...

  7. Video Stores: Introduction

    E-Print Network [OSTI]

    Scheible, Jeff; Neves, Joshua

    2010-01-01T23:59:59.000Z

    Journal, and a former video manager of Kim's Mediapolis inMEDIA FELDS J O U R N A L Video Stores Introduction Jeffa specific media space: the video rental store. We were

  8. Sandia National Laboratories: Videos

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

    Videos CSP Images & Videos On September 26, 2012, in Image Gallery Videos Concentrating Solar Power Image Gallery A picture says a thousand words, especially on the World Wide Web....

  9. Video:S. Hakan Armagan

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1 - USAFofEmail Mr. WilliamVideo: Watch the Open

  10. The Warped Disc of NGC 4258

    E-Print Network [OSTI]

    Rebecca G. Martin

    2008-04-07T23:59:59.000Z

    We consider the properties of the warped accretion disc in NGC 4258 which is delineated by maser emission. We use our analytical models to consider whether the disc could be warped by Lense-Thirring precession. We show that such models fit the shape of the disc well and we determine the goodness of fit for various combinations of the warp radius and the disc and black hole configurations. Though the fits are compelling evidence, we note that such a model has implications for the formation and longevity of the disc which might be problematic for the current understanding of Seyfert Galaxies.

  11. Video-Visuals

    Broader source: Energy.gov [DOE]

    Multimedia resources at the United States Department of Energy help to message geothermal development visually through video, photographs, renderings of the subsurface, and resource maps. VIDEO links

  12. On the Eddington limit in accretion discs

    E-Print Network [OSTI]

    D. Heinzeller; W. J. Duschl

    2006-10-25T23:59:59.000Z

    Although the Eddington limit has originally been derived for stars, recently its relevance for the evolution of accretion discs has been realized. We discuss the question whether the classical Eddington limit - which has been applied globally for almost all calculations on accretion discs - is a good approximation if applied locally in the disc. For this purpose, a critical accretion rate corresponding to this type of modified classical Eddington limit is calculated from thin alpha-disc models and slim disc models. We account for the non-spherical symmetry of the disc models by computing the local upper limits on the accretion rate from vertical and radial force equilibria separately. It is shown that the results can differ considerably from the classical (global) value: The vertical radiation force limits the maximum accretion rate in the inner disc region to much less than the classical Eddington value in thin alpha-discs, while it allows for significantly higher accretion rates in slim discs. We discuss the implications of these results for the evolution of accretion discs and their central objects.

  13. Accretion Discs with Strong Toroidal Magnetic Fields

    E-Print Network [OSTI]

    M. C. Begelman; J. E. Pringle

    2006-12-12T23:59:59.000Z

    Simulations and analytic arguments suggest that the turbulence driven by magnetorotational instability (MRI) in accretion discs can amplify the toroidal (azimuthal) component of the magnetic field to a point at which magnetic pressure exceeds the combined gas + radiation pressure in the disc. Arguing from the recent analysis by Pessah and Psaltis, and other MRI results in the literature, we conjecture that the limiting field strength for a thin disc is such that the Alfven speed roughly equals the geometric mean of the Keplerian speed and the gas sound speed. We examine the properties of such magnetically-dominated discs, and show that they resolve a number of outstanding problems in accretion disc theory. The discs would be thicker than standard (Shakura-Sunyaev) discs at the same radius and accretion rate, and would tend to have higher colour temperatures. If they transport angular momentum according to an alpha-prescription, they would be stable against the thermal and viscous instabilities that are found in standard disc models. In discs fuelling active galactic nuclei, magnetic pressure support could also alleviate the restriction on accretion rate imposed by disc self-gravity.

  14. Relevant Videos: Stoichiometry

    E-Print Network [OSTI]

    Houston, Paul L.

    #12;2 of 8 Relevant Videos: Stoichiometry Stoichiometry: Limiting Reagent Suspensions, Colloids note that MANY of these Khan chemistry videos contain errors, although the basic premise and overall content is sound. If you find an error in a video, please email me the following information: video title

  15. Video Summarization via Crowdsourcing

    E-Print Network [OSTI]

    Chen, Sheng-Wei

    Video Summarization via Crowdsourcing Abstract Although video summarization has been studied extensively, existing schemes are neither lightweight nor generalizable to all types of video content. To generate accurate abstractions of all types of video, we propose a framework called Click2SMRY, which

  16. Accretion and plasma outflow from dissipationless discs

    E-Print Network [OSTI]

    Sergei Bogovalov; Stanislav Kelner

    2008-09-02T23:59:59.000Z

    We consider an extreme case of disc accretion onto a gravitating centre when the viscosity in the disc is negligible. The angular momentum and the rotational energy of the accreted matter is carried out by a magnetized wind outflowing from the disc. The outflow of matter from the disc occurs due to the Blandford & Payne(1982) centrifugal mechanism. The disc is assumed to be cold. Accretion and outflow are connected by the conservation of the energy, mass and the angular momentum. The basic properties of the outflow, angular momentum flux and energy flux per particle in the wind, do not depend on the details of the structure of the accretion disc. In the case of selfsimilar accretion/outflow, the dependence of the rate of accretion $\\dot M$ in the disc depends on the disc radius $r$ on the law $\\dot M \\sim r^{{1\\over2(\\alpha^2-1)}}$, where $\\alpha$ is a dimensionless Alfvenic radius. In the case of $\\alpha \\gg 1$, the accretion in the disc is provided by very weak matter outflow from the disc and the outflow predominantly occurs from the very central part of the disc. The solution obtained in the work provides mechanism which transforms the gravitational energy of the accreted matter into the energy of the outflowing wind with efficiency close to 100%. The final velocity can essentially exceed Kepler velocity at the site of the wind launch. This mechanism allows us to understand the nature of the astrophysical objects with low luminosity discs and energetic jet-like outflows.

  17. The Roles of Discs for Planetary Systems

    E-Print Network [OSTI]

    Li-Chin Yeh; Ing-Guey Jiang

    2007-01-29T23:59:59.000Z

    It is known that the discs are detected for some of the extra-solar planetary systems. It is also likely that there was a disc mixing with planets and small bodies while our Solar System was forming. From our recent results, we conclude that the discs play two roles: the gravity makes planetary systems more chaotic and the drag makes planetary systems more resonant.

  18. HD 98800: A most unusual debris disc

    E-Print Network [OSTI]

    P. E. Verrier; N. W. Evans

    2008-07-31T23:59:59.000Z

    The dynamics of planetesimals in the circumbinary debris disc of the quadruple star system HD 98800 are investigated. Evolving a spherical shell of test particles from a million years ago to the present day indicates that both coplanar and retrograde warped discs could exist, as well as a high inclination halo of material. Significant gaps are seen in the discs, as well as unexpected regions of stability due to the retrograde nature of the stellar orbits. Despite a viewing angle almost perpendicular to the direction of the warp of the planetesimal disc it is still intersected by the line of sight for eccentricities of the outer orbit of 0.5 or less.

  19. accretion disc 2d: Topics by E-print Network

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

    of a dwarf novae disc through its outburst cycle, from isolating the spectrum of a disc wind to revealing the geometry of disc spiral shocks. I end with an outline of the future...

  20. accretion discs ii: Topics by E-print Network

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

    of a dwarf novae disc through its outburst cycle, from isolating the spectrum of a disc wind to revealing the geometry of disc spiral shocks. I end with an outline of the future...

  1. accretion disc origin: Topics by E-print Network

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

    of a dwarf novae disc through its outburst cycle, from isolating the spectrum of a disc wind to revealing the geometry of disc spiral shocks. I end with an outline of the future...

  2. accretion disc viewed: Topics by E-print Network

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

    of a dwarf novae disc through its outburst cycle, from isolating the spectrum of a disc wind to revealing the geometry of disc spiral shocks. I end with an outline of the future...

  3. accretion disc structure: Topics by E-print Network

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

    of a dwarf novae disc through its outburst cycle, from isolating the spectrum of a disc wind to revealing the geometry of disc spiral shocks. I end with an outline of the future...

  4. Accelerated planetesimal growth in self-gravitating protoplanetary discs

    E-Print Network [OSTI]

    Rice, William K; Lodato, G; Pringle, J E; Armitage, P J; Bonnell, I A

    2004-01-01T23:59:59.000Z

    self-gravitating protoplanetary discs W. K. M. Rice, 1 † G.in marginally stable, self-gravitating protoplanetary discs.The drag force between the disc gas and the em- bedded

  5. Collaborative Editor Environments for Player Programs

    E-Print Network [OSTI]

    SSL #11-12 #12;2 #12;3 Collaborative Editor Environments for Player Programs Sonny Thai, Dr. Alvar Saenz-Otero May 2012 SSL #11-12 This work is based on the unaltered text of the thesis by Sonny Thai

  6. Spectral energy distributions of selfgravitating QSO discs

    E-Print Network [OSTI]

    Edwin Sirko; Jeremy Goodman

    2002-09-23T23:59:59.000Z

    We calculate spectral energy distributions (SEDs) of steady accretion discs at high accretion rates, as appropriate for bright QSOs, under the assumption that the outer parts are heated sufficiently to maintain marginal gravitational stability, presumably by massive stars formed within the disc. The SED is independent of the nature of these auxiliary sources if their inputs are completely thermalized. Standard assumptions are made for angular momentum transport, with an alpha parameter less than unity. With these prescriptions, the luminosity of the disc is sensitive to its opacity, in contrast to standard discs powered by release of orbital energy alone. Compared to the latter, our discs have a broader SED, with a second peak in the near-infrared that is energetically comparable to the blue bump. The energy in the second peak increases with the outer radius of the disc, provided that the accretion rate is constant with radius. By comparing our computed SEDs with observed ones, we limit the outer radius of the disc to be less than 10^5 Schwarzschild radii, or about one parsec, in a typical QSO. We also discuss some properties of our minimum-Q discs in the regions where auxiliary heating is dominant (10^3-10^5 Schwarzschild radii).

  7. The tidal disruption of protoplanetary accretion discs

    E-Print Network [OSTI]

    John D. Larwood

    1997-05-30T23:59:59.000Z

    In this paper we revisit the problem of the tidal interaction occuring between a protostellar accretion disc and a secondary point mass following a parabolic trajectory. We model the disc response analytically and we compare our results with three-dimensional SPH simulations. Inviscid as well as viscous hydrodynamics is considered. We show that in a viscous system the response derived from inviscid considerations is predominant even for the highest estimates of an anomalous disc shear viscosity. The angular momentum lost from the disc during the encounter is derived from linear theory, for distant fly-bys, as well as the changes to the disc orientation expected in non-coplanar encounters. It is shown that the target discs can become warped and precess by a small amount during non-coplanar encounters. This small precession is shown to give rise to a relative tilt of the disc which is always more important for determining its final orientation than is the change to the orbital inclination. We discuss the implications of our results for protostellar accretion discs and planetary systems.

  8. From discs to planetesimals I: evolution of gas and dust discs

    E-Print Network [OSTI]

    Richard Alexander

    2007-12-03T23:59:59.000Z

    I review the processes that shape the evolution of protoplanetary discs around young, solar-mass stars. I first discuss observations of protoplanetary discs, and note in particular the constraints these observations place on models of disc evolution. The processes that affect the evolution of gas discs are then discussed, with the focus in particular on viscous accretion and photoevaporation, and recent models which combine the two. I then discuss the dynamics and growth of dust grains in discs, considering models of grain growth, the gas-grain interaction and planetesimal formation, and review recent research in this area. Lastly, I consider the so-called "transitional" discs, which are thought to be observed during disc dispersal. Recent observations and models of these systems are reviewed, and prospects for using statistical surveys to distinguish between the various proposed models are discussed.

  9. artificial disc replacement: Topics by E-print Network

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

    in three-dimensional discs CERN Preprints Summary: Vortex formation through the Rossby wave instability (RWI) in protoplanetary discs has been invoked to play a role in planet...

  10. artificial cervical disc: Topics by E-print Network

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

    in three-dimensional discs CERN Preprints Summary: Vortex formation through the Rossby wave instability (RWI) in protoplanetary discs has been invoked to play a role in planet...

  11. artificial disc arthroplasty: Topics by E-print Network

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

    in three-dimensional discs CERN Preprints Summary: Vortex formation through the Rossby wave instability (RWI) in protoplanetary discs has been invoked to play a role in planet...

  12. THE GAME, FIELD, PLAYERS AND EQUIPMENT General Rules

    E-Print Network [OSTI]

    Baltisberger, Jay H.

    metal cleats are permitted. (See illegal player equipment) Game and Player Equipment (Illegal) 1. A player wearing illegal equipment shall not be permitted to play. This applies to any equipment, which be declared illegal include: A. Headgear containing any hard, unyielding, or stiff material, including billed

  13. Sandia National Laboratories: Video

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

    Video SMART Rotor Video On September 17, 2012, in (Lighting and) Solid-State Lighting: Science, Technology, Economic Perspectives On July 30, 2012, in (Lighting and) Solid-State...

  14. Video face replacement

    E-Print Network [OSTI]

    Dale, Kevin

    We present a method for replacing facial performances in video. Our approach accounts for differences in identity, visual appearance, speech, and timing between source and target videos. Unlike prior work, it does not ...

  15. Video annotation tools

    E-Print Network [OSTI]

    Chaudhary, Ahmed

    2008-10-10T23:59:59.000Z

    general purpose annotation toolkits that can be used to create domain specific applications. A video annotation toolkit along with toolkits for searching, retrieving, analyzing and presenting videos can help achieve the broader goal of creating integrated...

  16. CFN | Video Library

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

    CFN Video Library Other Videos 436 Kevin Yager Kevin Yager on the Nanoscience of Studying Scattered X-rays Kevin Yager, a scientist at Brookhaven Lab's Center for Functional...

  17. IME Video Library http://videos.med.wisc.edu

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    ! What types of presentations are in the Video Library? Expert lecturers from the University of WisconsinIME Video Library http://videos.med.wisc.edu A collection of free streaming audio and video Communications #12;What is the IME Video Library? The Innovations in Medical Education (IME) Video Library

  18. VIDEO SUMMARIZATION BY VIDEO STRUCTURE ANALYSIS AND GRAPH OPTIMIZATION

    E-Print Network [OSTI]

    King, Kuo Chin Irwin

    VIDEO SUMMARIZATION BY VIDEO STRUCTURE ANALYSIS AND GRAPH OPTIMIZATION Shi Lu, Irwin King video summarization method that combines video structure analysis and graph optimiza- tion. First, we analyze the structure of the video, find the boundaries of video scenes, then we calculate each scene

  19. Videos | Argonne National Laboratory

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

    Videos Browse By - Any - General Argonne Information -Awards -Honors Energy -Energy efficiency --Vehicles ---Alternative fuels ---Automotive engineering ---Biofuels ---Diesel...

  20. Videos | Argonne National Laboratory

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

    Internship Videos Browse By - Any - General Argonne Information -Awards -Honors Energy -Energy efficiency --Vehicles ---Alternative fuels ---Automotive engineering ---Biofuels...

  1. Energy Literacy Videos

    K-12 Energy Lesson Plans and Activities Web site (EERE)

    New video series, Energy Literacy highlights the 7 Essential Principles of Energy to help engage students in energy.

  2. The Digital Interactive Video

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The Digital Interactive Video Exploration and Reflection (Diver) system lets users create virtual pathways through existing video content using a virtual camera and an annotation window for commentary repurposing, and discussion. W ith the inexorable growth of low-cost consumer video elec- tronics

  3. Digitales Video Martin Knopp

    E-Print Network [OSTI]

    Digitales Video Martin Knopp Thomas Hach � #12;Technische Universität MünchenLehrstuhl für Datenverarbeitung Bayermaske - Original 14Digitales Video #12;Technische Universität MünchenLehrstuhl für Datenverarbeitung Bayermaske - ,,Bayermasken-Bild" 15Digitales Video #12;Technische Universität MünchenLehrstuhl für

  4. Structure and kinematics of edge-on galaxy discs -- V. The dynamics of the stellar discs

    E-Print Network [OSTI]

    M. Kregel; P. C. van der Kruit; K. C. Freeman

    2005-01-24T23:59:59.000Z

    In earlier papers in this series we determined the intrinsic stellar disc kinematics of fifteen intermediate to late type edge-on spiral galaxies using a dynamical modeling technique. From the photometry we find that intrinsically more flattened discs tend to have a lower face-on central surface brightness and a larger dynamica mass-to-light ratio. This observation suggests that at a constant maximum rotational velocity lower surface brightness discs have smaller vertical stellar velocity dispersions.Although the individual uncertainties are large, we find from the dynamical modeling that at least twelve discs are submaximal. The average disc contributes 53$\\pm$4 percent to the observed rotation at 2.2 disc scalelengths, with a 1$\\sigma$ scatter of 15 percent. This percentage becomes somewhat lower when effects of finite disc flattening and gravity by the dark halo and the gas are taken into account. Since boxy and peanut-shaped bulges are probably associated with bars, the result suggests that at 2.2$h_{\\rm R}$ the submaximal nature of discs is independent of barredness. The possibility remains that very high surface brightness discs are maximal.We confirm that the radial stellar disc velocity dispersion is related to the galaxy maximum rotational velocity. The scatter in this $\\sigma-v_{\\rm max}$ relation appears to correlate with the disc flattening, face-on central surface brightness and dynamical mass-to-light ratio. Low surface brightness discs tend to be more flattened and have smaller stellar velocity dispersions. The findings are consistent with the observed correlation between disc flattening and dynamical mass-to-light ratio.

  5. Gravitationally coupled scale-free discs

    E-Print Network [OSTI]

    Yue Shen; Yu-Qing Lou

    2004-06-16T23:59:59.000Z

    In a composite fluid system of two gravitationally coupled barotropic scale-free discs bearing a rotation curve $v\\propto r^{-\\beta}$ and a power-law surface mass density $\\Sigma_0\\propto r^{-\\alpha}$ with $\\alpha=1+2\\beta$, we construct coplanar stationary aligned and spiral perturbation configurations in the two discs. Due to the mutual gravitational interaction, there are two independent classes of perturbation modes with surface mass density disturbances in the two coupled discs being either in-phase or out-of-phase. We derive analytical criteria for such perturbation modes to exist and show numerical examples. We compute the aligned and spiral perturbation modes systematically to explore the entire parameter regime. For the axisymmetric $m=0$ case with radial oscillations, there are two unstable regimes of ring-fragmentation and collapse corresponding to short and long radial wavelengths, respectively. Only within a certain range of the rotation parameter $D_s^2$ (square of the effective Mach number for the stellar disc), can a composite disc system be stable against all axisymmetric perturbations. Compared with a single-disc system, the coupled two-disc system becomes less stable against such axisymmetric instabilities.

  6. Three-dimensional SPH simulations of accretion discs

    E-Print Network [OSTI]

    Henri M. J. Boffin; Kei Haraguchi; Takuya Matsuda

    1998-12-01T23:59:59.000Z

    We discuss some 3D numerical simulations of accretion discs using the SPH method and a polytropic equation of state. We show that discs exist even for as large value of the polytropic index as 1.2, and that these discs are always in hydrostatic balance. We also show that even without any inflow, spiral shocks appear in the discs.

  7. Variability of black hole accretion discs: The cool, thermal disc component

    E-Print Network [OSTI]

    M. Mayer; J. E. Pringle

    2006-01-29T23:59:59.000Z

    We extend the model of King et al. (2004) for variability in black hole accretion discs, by taking proper account of the thermal properties of the disc. Because the degree of variability in the King et al. (2004) model depends sensitively on the ratio of disc thickness to radius, H/R, it is important to follow the time-dependence of the local disc structure as the variability proceeds. In common with previous authors, we develop a one-zone model for the local disc structure. We agree that radial heat advection plays an important role in determining the inner disc structure, and also find limit-cycle behaviour. When the stochastic magnetic dynamo model of King et al. (2004) is added to these models, we find similar variability behaviour to before. We are now better placed to put physical constraints on model parameters. In particular, we find that in order to be consistent with the low degree of variability seen in the thermal disc component of black hole binaries, we need to limit the energy density of the poloidal field that can be produced by local dynamo cells in the disc to less than a few percent of the energy density of the dynamo field within the disc itself.

  8. Planet formation in self-gravitating discs 

    E-Print Network [OSTI]

    Gibbons, Peter George

    2013-11-28T23:59:59.000Z

    The work performed here studies particle dynamics in local two-dimensional simulations of self-gravitating accretion discs with a simple cooling law. It is well known that the structure which arises in the gaseous component ...

  9. Digital Video 1 DIGITAL VIDEO, LEARNING STYLES AND STUDENT UNDERSTANDING

    E-Print Network [OSTI]

    Larkin, Teresa L.

    Digital Video 1 DIGITAL VIDEO, LEARNING STYLES AND STUDENT UNDERSTANDING Digital Video, Learning University in 1997. Her doctoral work involved the assessment of and interactive digital video technique #12;Digital Video 2 teachers, particularly those teachers whose background does not include

  10. Video and Image Processing in Multimedia Systems (Video Processing)

    E-Print Network [OSTI]

    Furht, Borko

    COT 6930 Video and Image Processing in Multimedia Systems (Video Processing) Instructor: Borko. Content-based image and video indexing and retrieval. Video processing using compressed data. Course concepts and structures 4. Classification of compression techniques 5. Image and video compression

  11. Particle Acceleration in (by) Accretion Discs

    E-Print Network [OSTI]

    J. I. Katz

    1992-05-04T23:59:59.000Z

    I present a model for acceleration of protons by the second-order Fermi process acting on randomly scrambled magnetic flux arches above an accretion disc. The accelerated protons collide with thermal protons in the disc, producing degraded energetic protons, charged and neutral pions, and neutrons. The pions produce gamma-rays by spontaneous decay of $\\pi^0$ and by bremsstrahlung and Compton processes following the decay of $\\pi^\\pm$ to $e^\\pm$.

  12. Photoevaporation of protoplanetary discs I: hydrodynamic models

    E-Print Network [OSTI]

    R. D. Alexander; C. J. Clarke; J. E. Pringle

    2006-03-09T23:59:59.000Z

    In this paper we consider the effect of the direct ionizing stellar radiation field on the evolution of protoplanetary discs subject to photoevaporative winds. We suggest that models which combine viscous evolution with photoevaporation of the disc (e.g. Clarke, Gendrin & Sotomayor 2001) incorrectly neglect the direct field after the inner disc has drained, at late times in the evolution. We construct models of the photoevaporative wind produced by the direct field, first using simple analytic arguments and later using detailed numerical hydrodynamics. We find that the wind produced by the direct field at late times is much larger than has previously been assumed, and we show that the mass-loss rate scales as $R_{in}^{1/2}$ (where $R_{in}$ is the radius of the instantaneous inner disc edge). We suggest that this result has important consequences for theories of disc evolution, and go on to consider the effects of this result on disc evolution in detail in a companion paper (Alexander, Clarke & Pringle 2006b).

  13. Turbulent drag reduction through oscillating discs

    E-Print Network [OSTI]

    Wise, Daniel J

    2014-01-01T23:59:59.000Z

    The changes of a turbulent channel flow subjected to oscillations of wall flush-mounted rigid discs are studied by means of direct numerical simulations. The Reynolds number is $R_\\tau$=$180$, based on the friction velocity of the stationary-wall case and the half channel height. The primary effect of the wall forcing is the sustained reduction of wall-shear stress, which reaches a maximum of 20%. A parametric study on the disc diameter, maximum tip velocity, and oscillation period is presented, with the aim to identify the optimal parameters which guarantee maximum drag reduction and maximum net energy saving, computed by taking into account the power spent to actuate the discs. This may be positive and reaches 6%. The Rosenblat viscous pump flow is used to predict the power spent for disc motion in the turbulent channel flow and to estimate localized and transient regions over the disc surface subjected to the turbulent regenerative braking effect, for which the wall turbulence exerts work on the discs. The...

  14. Video Toroid Cavity Imager

    DOE Patents [OSTI]

    Gerald, Rex E. II; Sanchez, Jairo; Rathke, Jerome W.

    2004-08-10T23:59:59.000Z

    A video toroid cavity imager for in situ measurement of electrochemical properties of an electrolytic material sample includes a cylindrical toroid cavity resonator containing the sample and employs NMR and video imaging for providing high-resolution spectral and visual information of molecular characteristics of the sample on a real-time basis. A large magnetic field is applied to the sample under controlled temperature and pressure conditions to simultaneously provide NMR spectroscopy and video imaging capabilities for investigating electrochemical transformations of materials or the evolution of long-range molecular aggregation during cooling of hydrocarbon melts. The video toroid cavity imager includes a miniature commercial video camera with an adjustable lens, a modified compression coin cell imager with a fiat circular principal detector element, and a sample mounted on a transparent circular glass disk, and provides NMR information as well as a video image of a sample, such as a polymer film, with micrometer resolution.

  15. Sandia National Laboratories: Nuclear Energy Videos

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

    Videos Nuclear Energy Videos The Nuclear Energy Capabilities video is 40 minutes long, but is broken into video segments for each capability. You may select a specific capability...

  16. Digitales Video Martin Knopp

    E-Print Network [OSTI]

    Digitales Video Martin Knopp Thomas Hach � #12;Technische Universität MünchenLehrstuhl für Datenverarbeitung 2 Poster ­ Was ist das? Digitales Video #12;Technische Universität MünchenLehrstuhl für Datenverarbeitung 3 Konferenzen Digitales Video #12;Technische Universität MünchenLehrstuhl für Datenverarbeitung 4

  17. Digitales Video Martin Knopp

    E-Print Network [OSTI]

    Digitales Video Martin Knopp Thomas Hach � #12;Technische Universität MünchenLehrstuhl für/Dilatation ­ Open/Close 2Digitales Video #12;Technische Universität MünchenLehrstuhl für Datenverarbeitung Post Medianfilter oder Max-/Min-Filter 3 a b c d e Ausgangsbild Ergebnis Digitales Video #12;Technische Universität

  18. The Disc-Jet Connection

    E-Print Network [OSTI]

    Ralph E. Pudritz; Robi Banerjee

    2005-07-11T23:59:59.000Z

    A large body of theoretical and computational work shows that jets - modelled as magnetized disk winds - exert an external torque on their underlying disks that can efficiently remove angular momentum and act as major drivers of disk accretion. These predictions have recently been confirmed in direct HST measurements of the jet rotation and angular momentum transport in low mass protostellar systems. We review the theory of disc winds and show that their physics is universal and scales to jets from both low and high mass star forming regions. This explains the observed properties of outflows in massive star forming regions, before the central massive star generates an ultracompact HII region. We also discuss the recent numerical studies on the formation of massive accretion disks and outflows through gravitational collapse, including our own work on 3D Adaptive Mesh simulations (using the FLASH code) of the hydromagnetic collapse of an initial rotating, and cooling Bonner-Ebert sphere. Magnetized collapse gives rise to outflows. Our own simulations show that both a jet-like disk wind on sub AU scales, and a larger scale molecular outflow occur (Banerjee and Pudritz 2005).

  19. Geothermal: Promotional Video

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

    Promotional Video Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us HomeBasic Search About Publications Advanced Search New Hot Docs News Related Links...

  20. Video Clip Quiz

    E-Print Network [OSTI]

    User

    2014-12-15T23:59:59.000Z

    Math 13700. Video Quiz. 2015. For this quiz, please go to the following website: http://crmse.sdsu.edu/nickerson. If you experience any difficulties with watching ...

  1. Video Clip Quiz

    E-Print Network [OSTI]

    User

    2013-01-02T23:59:59.000Z

    Math 13700. Video Quiz. 2013. For this quiz, please go to the following website: http://crmse.sdsu.edu/nickerson. If you experience any difficulties with watching ...

  2. Video Clip Quiz

    E-Print Network [OSTI]

    rroames

    2010-01-20T23:59:59.000Z

    Math 13800. Video Quiz. Spring 2010. For this quiz, please go to the following website: http://www.sdsu-pdc.org/nickerson/. If you experience any difficulties with ...

  3. Multiplexing video streams using dual-frame video coding

    E-Print Network [OSTI]

    Tiwari, M; Groves, T; Cosman, P C

    2008-01-01T23:59:59.000Z

    novel idea for multiplexing video streams was to combine theLTR frames in dual-frame video coding with EqualSlope. T.Luthra, “Overview of the H.264/AVC video coding standard,”

  4. Slug pellet spreading: the double-disc performances available with a single disc spreader

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Slug pellet spreading: the double-disc performances available with a single disc spreader D for slug pellets application. The principal aim of this paper is to show the chosen way to reach spreading pellets 1 Introduction In France, slugs are considered as a harmful destroyer for crops. Their activities

  5. U-104: Adobe Flash Player Multiple Vulnerabilities | Department...

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

    have been reported in Adobe Flash Player, which can be exploited by malicious people to conduct cross-site scripting attacks, bypass certain security restrictions, and...

  6. The Evolution of Stellar Exponential Discs

    E-Print Network [OSTI]

    Annette Ferguson; Cathie Clarke

    2001-03-14T23:59:59.000Z

    Models of disc galaxies which invoke viscosity-driven radial flows have long been known to provide a natural explanation for the origin of stellar exponential discs, under the assumption that the star formation and viscous timescales are comparable. We present models which invoke simultaneous star formation, viscous redistribution of gas and cosmologically-motivated gaseous infall and explore the predictions such models make for the scale length evolution and radial star formation history of galactic stellar discs. While the inclusion of viscous flows is essential for ensuring that the stellar disc is always exponential over a significant range in radius, we find that such flows play essentially no role in determining the evolution of the disc scale length. In models in which the main infall phase precedes the onset of star formation and viscous evolution, we find the exponential scale length to be rather invariant with time. On the other hand, models in which star formation/viscous evolution and infall occur concurrently result in a smoothly increasing scale length with time, reflecting the mean angular momentum of material which has fallen in at any given epoch. The disc stellar populations in these models are predominantly young (ie. ages < 5 Gyr) beyond a few scale lengths. In both cases, viscous flows are entirely responsible for transporting material to very large radii. We discuss existing observational constraints on these models from studies of both local and moderate redshift disc galaxies. In particular, a good agreement is found between the solar neighbourhood star formation history predicted by our infall model and the recent observational determination of this quantity by Rocha-Pinto et al (2000).

  7. Exact General Relativistic Discs and the Advance of Perihelion

    E-Print Network [OSTI]

    D. Vogt; P. S. Letelier

    2008-05-20T23:59:59.000Z

    The advance of perihelion for geodesic motion on the galactic plane of some exact general relativistic disc solutions is calculated. Approximate analytical and numerical results are presented for the static Chazy-Curzon and the Schwarzschild discs in Weyl coordinates, the Schwarzschid disc in isotropic coordinantes and the stationary Kerr disc in the Weyl-Lewis-Papapetrou metrics. It is found that for these disc models the advance of perihelion may be an increasing or decreasing function of the orbital excentricity. The precession due to Newtonian gravity for these disc models is also calculated.

  8. Video Library | Advanced Photon Source

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

    APS Brochure Annual Reports Posters Podcasts Image Gallery external site Video Library Syndicated Feeds (RSS) Now Playing: The Advanced Photon Source More videos: Building...

  9. Video Library | Advanced Photon Source

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

    APS Brochure Annual Reports Posters Podcasts Image Gallery external site Video Library Syndicated Feeds (RSS) Featured Videos: Introduction to the Advanced Photon Source...

  10. Video Library | Advanced Photon Source

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

    Video Library Related Links: APS Colloquium APS Podcasts APS Today More videos: Introduction to the APS Physics of the Blues Now Playing: Building the Advanced Photon Source This...

  11. Sandia Energy - SMART Rotor Video

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

    SMART Rotor Video Home Stationary Power Energy Conversion Efficiency Wind Energy Resources Wind Energy Publications Online Abstracts and Reports SMART Rotor Video SMART Rotor...

  12. Satellites in Discs: Regulating the Accretion Luminosity

    E-Print Network [OSTI]

    Dave Syer; Cathie Clarke

    1995-05-04T23:59:59.000Z

    We demonstrate, using a simple analytic model, that the presence of a massive satellite can globally modify the structure and emission properties of an accretion disc to which it is tidally coupled. We show, using two levels of numerical approximation, that the analytic model gives reasonable results. The results are applicable to two astrophysical situations. In the case of an active galactic nucleus, we consider the case of a $\\sim 10^3\\Msun$ compact companion to the central black-hole and show that it could modulate the emitted spectrum on a timescale of $\\sim10^5$ years. In the case of a T Tauri accretion disc, a satellite such as a sub-dwarf or giant planet could modify the disc spectral energy distribution over a substantial fraction of the T Tauri star lifetime.

  13. Organizational Roles and Players Alan W Colman and Jun Han

    E-Print Network [OSTI]

    Han, Jun

    Organizational Roles and Players Alan W Colman and Jun Han Faculty of Information and Communication,jhan}@it.swin.edu.au Abstract This paper discusses the characteristics of organizational roles. We point out differences between in organizational contexts, and show how the functional boundary between a role and its player varies depending

  14. Extending Neuro-evolutionary Preference Learning through Player Modeling

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Extending Neuro-evolutionary Preference Learning through Player Modeling H´ector P. Mart approach extends neuro-evolutionary preference learning by embedding a player modeling module preferences of users using neuro-evolutionary pref- erence learning has provided highly accurate computational

  15. Appearance of Keplerian discs orbiting Kerr superspinars

    E-Print Network [OSTI]

    Zdenek Stuchlik; Jan Schee

    2011-01-19T23:59:59.000Z

    We study optical phenomena related to appearance of Keplerian accretion discs orbiting Kerr superspinars predicted by the string theory. The superspinar exterior is described by the standard Kerr naked singularity geometry breaking the black hole limit on the internal angular momentum (spin). We construct local photon escape cones for a variety of orbiting sources that enable to determine the superspinars silhouette in the case of distant observers. We show that the superspinar silhouette depends strongly on the assumed edge where the external Kerr spacetime is joined to the internal spacetime governed by the string theory and significantly differs from the black hole silhouette. The appearance of the accretion disc is strongly dependent on the value of the superspinar spin in both their shape and frequency shift profile. Apparent extension of the disc grows significantly with growing spin, while the frequency shift grows with descending spin. This behavior differs substantially from appearance of discs orbiting black holes enabling thus, at least in principle, to distinguish clearly the Kerr superspinars and black holes. In vicinity of a Kerr superspinar the non-escaped photons have to be separated to those captured by the superspinar and those being trapped in its strong gravitational field leading to self-illumination of the disc that could even influence its structure and causes self-reflection effect of radiation of the disc. The amount of trapped photons grows with descending of the superspinar spin. We thus can expect significant self-illumination effects in the field of Kerr superspinars with near-extreme spin $a \\sim 1$.

  16. Video Visualization Gareth Daniel Min Chen

    E-Print Network [OSTI]

    Grant, P. W.

    Video Visualization Gareth Daniel Min Chen University of Wales Swansea, UK Abstract Video data, generated by the entertainment industry, security and traffic cameras, video conferencing systems, video a novel methodology for "summarizing" video sequences using volume visualization techniques. We outline

  17. The runaway instability of thick discs around black holes. II. Non constant angular momentum discs

    E-Print Network [OSTI]

    Frederic Daigne; Jose A. Font

    2003-11-28T23:59:59.000Z

    We present results from a comprehensive number of relativistic, time-dependent, axisymmetric simulations of the runaway instability of non-constant angular momentum thick discs around black holes. This second paper extends earlier results where only constant angular momentum discs were considered. All relevant aspects of the theory of stationary thick discs around rotating black holes, necessary to build the initial state in our simulations, are presented in great detail. The angular momentum of the discs is assumed to increase outwards with the radial distance according to a power law. The main simplifying assumptions of our approach are not to include magnetic fields and self-gravity in the discs. Furthermore, the dynamics of the spacetime is accounted for by computing the transfer of mass and angular momentum from the disc to the black hole through the event horizon : the evolution of the central black hole is assumed to follow a sequence of Kerr black holes of increasing mass and spin. In agreement with previous results based on stationary models we find that by allowing the mass and the spin of the black hole to grow, constant angular momentum discs rapidly become unstable on a dynamical timescale. The comparison with the results of paper I shows that the effect of the angular momentum transfer from the torus to the black hole is to make constant angular momentum discs less unstable, increasing the timescale of the instability. However, we find that non-constant angular momentum discs are dramatically stabilized for very small values of the angular momentum slope. Our time-dependent simulations confirm, thus, the predictions of stationary studies concerning the stabilizing effect of non-constant angular momentum distributions.

  18. Disc valve for sampling erosive process streams

    DOE Patents [OSTI]

    Mrochek, J.E.; Dinsmore, S.R.; Chandler, E.W.

    1986-01-07T23:59:59.000Z

    A four-port disc valve is described for sampling erosive, high temperature process streams. A rotatable disc defining opposed first and second sampling cavities rotates between fired faceplates defining flow passageways positioned to be alternatively in axial alignment with the first and second cavities. Silicon carbide inserts and liners composed of [alpha] silicon carbide are provided in the faceplates and in the sampling cavities to limit erosion while providing lubricity for a smooth and precise operation when used under harsh process conditions. 1 fig.

  19. Hard Discs on the Hyperbolic Plane

    E-Print Network [OSTI]

    Carl D. Modes; Randall D. Kamien

    2007-11-30T23:59:59.000Z

    We examine a simple hard disc fluid with no long range interactions on the two dimensional space of constant negative Gaussian curvature, the hyperbolic plane. This geometry provides a natural mechanism by which global crystalline order is frustrated, allowing us to construct a tractable model of disordered monodisperse hard discs. We extend free area theory and the virial expansion to this regime, deriving the equation of state for the system, and compare its predictions with simulation near an isostatic packing in the curved space.

  20. accretion disc radii: Topics by E-print Network

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

    the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the...

  1. accretion discs due: Topics by E-print Network

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

    the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the...

  2. accretion discs formed: Topics by E-print Network

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

    the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the...

  3. accretion discs induced: Topics by E-print Network

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

    and the rotational energy of the accreted matter is carried out by a magnetized wind outflowing from the disc. The outflow of matter from the disc occurs due to the...

  4. accretion disc particle: Topics by E-print Network

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

    the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the...

  5. accretion disc dynamo: Topics by E-print Network

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

    the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the...

  6. accretion disc boundary: Topics by E-print Network

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

    the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the...

  7. Video Shoot Scope of Work

    Broader source: Energy.gov [DOE]

    Video Shoot Scope of Work, from the Tool Kit Framework: Small Town University Energy Program (STEP).

  8. Interactive Video Cubism Sidney Fels

    E-Print Network [OSTI]

    Fels, Sidney S.

    Interactive Video Cubism Sidney Fels Dept. of Electrical and Computer Engineering University@mic.atr.co.jp ABSTRACT This paper presents an interactive video visualization system. In this visualization video data is considered to be a block of three dimensional data where frames of video data comprise the third dimension

  9. U-241: Adobe Flash Player Bugs Let Remote Users Execute Arbitrary...

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

    41: Adobe Flash Player Bugs Let Remote Users Execute Arbitrary Code and Obtain Information U-241: Adobe Flash Player Bugs Let Remote Users Execute Arbitrary Code and Obtain...

  10. Demographics of Transition Discs in Ophiuchus and Taurus

    E-Print Network [OSTI]

    Najita, Joan R; Muzerolle, James

    2015-01-01T23:59:59.000Z

    Transition disc systems are young stars that appear to be on the verge of dispersing their protoplanetary discs. We explore the nature of these systems by comparing the stellar accretion rates and disc masses of transition discs and normal T Tauri stars in Taurus and Ophiuchus. After controlling for the known dependencies of stellar accretion rate and disc mass and on age, stellar accretion rate on stellar mass, and disc mass on the presence of stellar or sub-stellar companions, we find that the normal T Tauri stars show a trend of stellar accretion rate increasing with disc mass. The transition discs tend to have higher average disc masses than normal T Tauri stars as well as lower accretion rates than normal T Tauri stars of the same disc mass. These results are most consistent with the interpretation that the transition discs have formed objects massive enough to alter the accretion flow, i.e., single or multiple giant planets. Several Ophiuchus T Tauri stars that are not known transition disc systems also...

  11. DISC1–ATF4 transcriptional repression complex: dual regulation of the cAMP-PDE4 cascade by DISC1

    E-Print Network [OSTI]

    Ishizuka, K

    Disrupted-In-Schizophrenia 1 (DISC1), a risk factor for major mental illnesses, has been studied extensively in the context of neurodevelopment. However, the role of DISC1 in neuronal signaling, particularly in conjunction ...

  12. NREL Buildings Research Video

    ScienceCinema (OSTI)

    None

    2013-05-29T23:59:59.000Z

    Through research, the National Renewable Energy Laboratory (NREL) has developed many strategies and design techniques to ensure both commercial and residential buildings use as little energy as possible and also work well with the surroundings. Here you will find a video that introduces the work of NREL Buildings Research, highlights some of the facilities on the NREL campus, and demonstrates these efficient building strategies. Watch this video to see design highlights of the Science and Technology Facility on the NREL campus?the first Federal building to be LEED® Platinum certified. Additionally, the video demonstrates the energy-saving features of NRELs Thermal Test Facility. For a text version of this video visit http://www.nrel.gov/buildings/about_research_text_version.html

  13. Videos | Department of Energy

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

    The Levers and Gears of Electricity TED-Ed Video: A Guide to the Energy of the Earth 3D Printing in 30 Seconds LAYCCA STEM Fair 2014 Energy 101: Geothermal Energy The Hanford Story...

  14. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos Videos

  15. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos VideosEnergy 101: Home

  16. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos VideosEnergy 101:

  17. Disc valve for sampling erosive process streams

    DOE Patents [OSTI]

    Mrochek, J.E.; Dinsmore, S.R.; Chandler, E.W.

    1984-08-16T23:59:59.000Z

    This is a patent for a disc-type, four-port sampling valve for service with erosive high temperature process streams. Inserts and liners of ..cap alpha..-silicon carbide respectively, in the faceplates and in the sampling cavities, limit erosion while providing lubricity for a smooth and precise operation. 1 fig.

  18. Counterrotating perfect fluid discs as sources of electrovacuum static spacetimes

    E-Print Network [OSTI]

    Gonzalo García-Reyes; Guillermo A. González

    2008-10-14T23:59:59.000Z

    The interpretation of some electrovacuum spacetimes in terms of counterrotating perfect fluid discs is presented. The interpretation is mades by means of an "inverse problem" approach used to obtain disc sources of known static solutions of the Einstein-Maxwell equations. In order to do such interpretation, a detailed study is presented of the counterrotating model (CRM) for generic electrovacuum static axially symmetric relativistic thin discs with nonzero radial pressure. Four simple families of models of counterrotating charged discs based on Chazy-Curzon-type, Zipoy-Voorhees-type, Bonnor-Sackfield-type, and charged and magnetized Darmois electrovacuum metrics are considered where we obtain some discs with a CRM well behaved.

  19. Tilted accretion discs in cataclysmic variables: tidal instabilities and superhumps

    E-Print Network [OSTI]

    J. R. Murray; P. J. Armitage

    1998-09-10T23:59:59.000Z

    We investigate the growth of tidal instabilities in accretion discs in a binary star potential, using three dimensional numerical simulations. As expected from analytic work, the disc is prone to an eccentric instability provided that it is large enough to extend to the 3:1 resonance. The eccentric disc leads to positive superhumps in the light curve. It has been proposed that negative superhumps might arise from a tilted disc, but we find no evidence that the companion gravitational tilt instability can grow fast enough in a fluid disc to create a measurable inclination. The origin of negative superhumps in the light curves of cataclysmic variables remains a puzzle.

  20. Broad reprocessed Balmer emission from warped accretion discs

    E-Print Network [OSTI]

    Sheng-Miao Wu; Ting-Gui Wang; Xiao-Bo Dong

    2008-07-11T23:59:59.000Z

    Double peaked broad emission lines in active galactic nuclei are generally considered to be formed in an accretion disc. In this paper, we compute the profiles of reprocessing emission lines from a relativistic, warped accretion disc around a black hole in order to explore the possibility that certain asymmetries in the double-peaked emission line profile which can not be explained by a circular Keplerian disc may be induced by disc warping. The disc warping also provides a solution for the energy budget in the emission line region because it increases the solid angle of the outer disc portion subtended to the inner portion of the disc. We adopted a parametrized disc geometry and a central point-like source of ionizing radiation to capture the main characteristics of the emission line profile from such discs. We find that the ratio between the blue and red peaks of the line profiles becoming less than unity can be naturally predicted by a twisted warped disc, and a third peak can be produced in some cases. We show that disc warping can reproduce the main features of multi-peaked line profiles of four active galactic nuclei from the Sloan Digital Sky Survey.

  1. Accretion Disc Evolution in Single and Binary T Tauri Stars

    E-Print Network [OSTI]

    Philip J. Armitage; C. J. Clarke; C. A. Tout

    1998-10-30T23:59:59.000Z

    We present theoretical models for the evolution of T Tauri stars surrounded by circumstellar discs. The models include the effects of pre-main-sequence stellar and time dependent disc evolution, and incorporate the effects of stellar magnetic fields acting on the inner disc. For single stars, consistency with observations in Taurus-Auriga demands that disc dispersal occurs rapidly, on much less than the viscous timescale of the disc, at roughly the epoch when heating by stellar radiation first dominates over internal viscous dissipation. Applying the models to close binaries, we find that because the initial conditions for discs in binaries are uncertain, studies of extreme mass ratio systems are required to provide a stringent test of theoretical disc evolution models. We also note that no correlation of the infra-red colours of T Tauri stars with their rotation rate is observed, in apparent contradiction to the predictions of simple magnetospheric accretion models.

  2. 2005 Getting Started with Epics Videos

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

    Video Library APS Colloquium Videos * 2007 * 2006 * 2005 * 2004 Getting Started with Epics * 2005 * 2004 2005 Getting Started with Epics Videos ASD Controls and AOD BCDA have...

  3. Nobel Lecture Series Videos Now Available Online

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

    Lecture Series Videos Now Available Online Nobel Lecture Videos Now Available Online May 29, 2014 by Kathy Kincade (0 Comments) Three of the NERSC Nobel Lecture Series videos --...

  4. Sandia National Laboratories: CSP Images & Videos

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

    Images & Videos CSP Images & Videos Image Gallery Videos Concentrating Solar Power Image Gallery A picture says a thousand words, especially on the World Wide Web. Both Sandia...

  5. Perceptual quality assessment for compressed video

    E-Print Network [OSTI]

    Yang, Kai-Chieh

    2007-01-01T23:59:59.000Z

    Overview of Video Quality Assessment . . . . . . . . . . . .2.3.1 Subjective Video Quality Assessment . . . . . . . .2.3.2 Objective Video Quality Assessment . . . . . . . . .

  6. DOE FEMA Videos | Department of Energy

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

    DOE FEMA Videos DOE FEMA Videos EMERGENCY RESPONSE TO A TRANSPORTATION ACCIDENT INVOLVING RADIOACTIVE MATERIAL This training video and user guide was designed to supplement the...

  7. Diet composition and performance of female collegiate soccer players 

    E-Print Network [OSTI]

    Clark, Mandy Michele

    2001-01-01T23:59:59.000Z

    intake. In conclusion, female soccer players appear to meet caloric needs during periods of training, but fail to meet minimum CHO and micronutrient recommendations. Foods higher in protein and fat, in addition to foods with low nutrient value may...

  8. Virial theorem for radiating accretion discs

    E-Print Network [OSTI]

    Patryk Mach

    2012-04-18T23:59:59.000Z

    A continuum version of the virial theorem is derived for a radiating self-gravitating accretion disc around a compact object. The central object is point-like, but we can avoid the regularization of its gravitational potential. This is achieved by applying a modified Pohozaev-Rellich identity to the gravitational potential of the disk only. The theorem holds for general stationary configurations, including discontinuous flows (shock waves, contact discontinuities). It is used to test numerical solutions of a model of self-gravitating radiative accretion discs. The presented virial theorem should be useful in the analysis of those (possibly radiating) hydrodynamical systems in astrophysics where the central mass and the mass of the fluid are comparable and none of them can be neglected.

  9. VIDEO TRANSCODING GATEWAY FOR WIRELESS VIDEO ACCESS Zhijun Lei, Nicolas D. Georganas

    E-Print Network [OSTI]

    Ottawa, University of

    -000 - VIDEO TRANSCODING GATEWAY FOR WIRELESS VIDEO ACCESS Zhijun Lei, Nicolas D. Georganas several typical video transcoding architectures and major applications of video transcoding. We identify issues involved in access video streams through handheld devices and wireless networks. To handle

  10. Videos | Partnerships | ORNL

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize AvailableMedia Room /Video Video Computational

  11. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos Videos <h3>Better

  12. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos Videos <h3>BetterSunShot

  13. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos Videos <h3>BetterSunShotThe

  14. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos VideosEnergy 101: Home Energy

  15. Videos | Department of Energy

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

    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 Delicious Rank EERE: Alternative JC3 RSS SeptemberRenewable Energy,Geothermal3:Videos VideosEnergy 101: HomeChevron

  16. The Photoevaporation of Discs Around Young Stars in Massive Clusters

    E-Print Network [OSTI]

    C. J. Clarke

    2007-02-05T23:59:59.000Z

    We present models in which the photoevaporation of discs around young stars by an external ultraviolet source (as computed by Adams et al 2004) is coupled with the internal viscous evolution of the discs. These models are applied to the case of the Orion Nebula Cluster, where the presence of a strong ultraviolet field from the central OB stars, together with a detailed census of circumstellar discs and photoevaporative flows, is well established. In particular we investigate the constraints that are placed on the initial disc properties in the ONC by the twin requirement that most stars possess a disc on a scale of a few A.U., but that only a minority ($ 0.1 M_\\odot$). The ubiquity of discs on a small scale, on the other hand, mainly constrains the timespan over which the discs have been exposed to the ultraviolet field ($< 2 $Myr). We argue that the discs that are resolved by HST represent a population of discs in which self-gravity was important at the time that the dominant central OB star switched on, but that, according to our models, self-gravity is unlikely to be important in these discs at the present time. We discuss the implications of our results for the so-called proplyd lifetime problem.

  17. Astrometric signatures of self-gravitating protoplanetary discs

    E-Print Network [OSTI]

    W. K. M. Rice; P. J. Armitage; M. R. Bate; I. A. Bonnell

    2002-09-09T23:59:59.000Z

    We use high resolution numerical simulations to study whether gravitational instabilities within circumstellar discs can produce astrometrically detectable motion of the central star. For discs with masses of M_disc = 0.1 M_star, which are permanantly stable against fragmentation, we find that the magnitude of the astrometric signal depends upon the efficiency of disc cooling. Short cooling times produce prominent filamentary spiral structures in the disc, and lead to stellar motions that are potentially observable with future high precision astrometric experiments. For a disc that is marginally unstable within radii of \\~10 au, we estimate astrometric displacements of 10-100 microarcsec on decade timescales for a star at a distance of 100 pc. The predicted displacement is suppressed by a factor of several in more stable discs in which the cooling time exceeds the local dynamical time by an order of magnitude. We find that the largest contribution comes from material in the outer regions of the disc and hence, in the most pessimistic scenario, the stellar motions caused by the disc could confuse astrometric searches for low mass planets orbiting at large radii. They are, however, unlikely to present any complications in searches for embedded planets orbiting at small radii, relative to the disc size, or Jupiter mass planets or greater orbiting at large radii.

  18. Dispersal of Gaseous Circumstellar Discs around High-Mass Stars

    E-Print Network [OSTI]

    Yue Shen; Yu-Qing Lou

    2006-05-19T23:59:59.000Z

    We study the dispersal of a gaseous disc surrounding a central high-mass stellar core once this circumstellar disc becomes fully ionized. If the stellar and surrounding EUV and X-ray radiations are so strong as to rapidly heat up and ionize the entire circumstellar disc as further facilitated by disc magnetohydrodynamic (MHD) turbulence, a shock can be driven to travel outward in the fully ionized disc, behind which the disc expands and thins. For an extremely massive and powerful stellar core, the ionized gas pressure overwhelms the centrifugal and gravitational forces in the disc. In this limit, we construct self-similar shock solutions for such an expansion and depletion phase. As a significant amount of circumstellar gas being removed, the relic disc becomes vulnerable to strong stellar winds and fragments into clumps. We speculate that disc disappearance happens rapidly, perhaps on a timescale of $\\sim 10^3-10^4\\hbox{yr}$ once the disc becomes entirely ionized sometime after the onset of thermal nuclear burning in a high-mass stellar core.

  19. Mass Flow and Accretion through gaps in Accretion Discs

    E-Print Network [OSTI]

    Willy Kley

    1998-09-21T23:59:59.000Z

    We study the structure and dynamics of the gap created by a protoplanet in an accretion disc. The hydrodynamic equations for a flat, two-dimensional, non-selfgravitating protostellar accretion disc with an embedded, Jupiter sized protoplanet on a circular orbit are solved. To simulate possible accretion of mass onto the protoplanet we continually remove mass from the interior of the planet's Roche lobe which is monitored. Firstly, it is shown that consistent results independent on numerical issues (such as boundary or initial conditions, artificial viscosity or resolution) can be obtained. Then, a detailed parameter study delineates the influence of the disc viscosity and pressure on the magnitude of the accretion rate. We find that, even after the formation of a gap in the disc, the planet is still able to accrete more mass from the disc. This accretion occurs from regions of the disc which are radially exterior and interior to the planet's orbital radius. The rate depends on the magnitude of the viscosity and vertical thickness of the disc. For a disc viscosity alpha=10^{-3} and vertical thickness H/r=0.05 we estimate the time scale for the accumulation of one Jupiter mass to be of order hundred thousand years. For a larger(smaller) viscosity and disc thickness this accretion rate is increasing(decreasing). For a very small viscosity (alpha disc.

  20. Video Entity Resolution: Applying ER Techniques for Smart Video Surveillance

    E-Print Network [OSTI]

    Kalashnikov, Dmitri V.

    buildings, smart grid, and so on. In this paper, we focus on smart surveillance systems wherein video improvements on how the building is used. One of the key challenges in building smart surveillance systemsVideo Entity Resolution: Applying ER Techniques for Smart Video Surveillance Liyan Zhang Ronen

  1. Video transmission over wireless networks 

    E-Print Network [OSTI]

    Zhao, Shengjie

    2005-08-29T23:59:59.000Z

    Compressed video bitstream transmissions over wireless networks are addressed in this work. We first consider error control and power allocation for transmitting wireless video over CDMA networks in conjunction with multiuser detection. We map a...

  2. Video transmission over wireless networks

    E-Print Network [OSTI]

    Zhao, Shengjie

    2005-08-29T23:59:59.000Z

    Compressed video bitstream transmissions over wireless networks are addressed in this work. We first consider error control and power allocation for transmitting wireless video over CDMA networks in conjunction with multiuser detection. We map a...

  3. San Francisco QER Meeting Video

    Broader source: Energy.gov [DOE]

    Watch videos from the June 19, 2014, Quadrennial Energy Review public stakeholder meeting in San Francisco, California.

  4. Deep Web video

    ScienceCinema (OSTI)

    None Available

    2012-03-28T23:59:59.000Z

    To make the web work better for science, OSTI has developed state-of-the-art technologies and services including a deep web search capability. The deep web includes content in searchable databases available to web users but not accessible by popular search engines, such as Google. This video provides an introduction to the deep web search engine.

  5. Deep Web video

    SciTech Connect (OSTI)

    None Available

    2009-06-01T23:59:59.000Z

    To make the web work better for science, OSTI has developed state-of-the-art technologies and services including a deep web search capability. The deep web includes content in searchable databases available to web users but not accessible by popular search engines, such as Google. This video provides an introduction to the deep web search engine.

  6. Video Resources Central Asia

    E-Print Network [OSTI]

    Qian, Ning

    ://archive.org/details/central-asia · Kyrgyzstan: Crisis in Kyrgyzstan: Fuel, Contracts, and Revolution along the Afghan Supply Chain http://www.c-span.org/video/?24094-1/crisis-kyrgyzstan-fuel-contracts-revolution-along- afghan-supply-chain 2:58 Alex Cooley · Cotton

  7. Simplifying Video Editing Using Metadata

    E-Print Network [OSTI]

    Stevens, Scott M.

    Simplifying Video Editing Using Metadata Juan Casares, A. Chris Long, Brad A. Myers, Rishi Institute, Carnegie Mellon University1 ABSTRACT Digital video is becoming increasingly ubiquitous. However, editing video remains difficult for several reasons: it is a time-based medium, it has dual tracks

  8. Accretion disc viscosity: a limit on the anisotropy

    E-Print Network [OSTI]

    Nixon, Chris

    2015-01-01T23:59:59.000Z

    Observations of warped discs can give insight into the nature of angular momentum transport in accretion discs. Only a few objects are known to show strong periodicity on long timescales, but when such periodicity is present it is often attributed to precession of the accretion disc. The X-ray binary Hercules X-1/HZ Herculis (Her X-1) is one of the best examples of such periodicity and has been linked to disc precession since it was first observed. By using the current best-fitting models to Her X-1, which invoke precession driven by radiation warping, I place a constraint on the effective viscosities that act in a warped disc. These effective viscosities almost certainly arise due to turbulence induced by the magneto-rotational instability. The constraints derived here are in agreement with analytical and numerical investigations into the nature of magneto-hydrodynamic disc turbulence, but at odds with some recent global simulations.

  9. [NeII] emission line profiles from photoevaporative disc winds

    E-Print Network [OSTI]

    R. D. Alexander

    2008-09-01T23:59:59.000Z

    I model profiles of the [NeII] forbidden emission line at 12.81um, emitted by photoevaporative winds from discs around young, solar-mass stars. The predicted line luminosities (~ 1E-6 Lsun) are consistent with recent data, and the line profiles vary significantly with disc inclination. Edge-on discs show broad (30-40km/s) double-peaked profiles, due to the rotation of the disc, while in face-on discs the structure of the wind results in a narrower line (~10km/s) and a significant blue-shift (5-10km/s). These results suggest that observations of [NeII] line profiles can provide a direct test of models of protoplanetary disc photoevaporation.

  10. On the observability of spiral structures in CV accretion discs

    E-Print Network [OSTI]

    Danny Steeghs; Rudolf Stehle

    1999-02-25T23:59:59.000Z

    We use the grid of hydrodynamic accretion disc calculations of Stehle (1999) to construct orbital phase dependent emission line profiles of thin discs carrying spiral density waves. The observational signatures of spiral waves are explored to establish the feasibility of detecting spiral waves in cataclysmic variable discs using prominent emission lines in the visible range of the spectrum. For high Mach number accretion discs (M = 15-30), we find that the spiral shock arms are so tightly wound that they leave few obvious fingerprints in the emission lines. Only a minor variation of the double peak separation in the line profile at a level of 8% is produced. For accretion discs in outburst (M = 5-20) however, the lines are dominated by the emission from an m=2 spiral pattern in the disc. We show that reliable Doppler tomograms of spiral shock patterns can be reconstructed provided that a signal to noise of at least 15, a wavelength resolution of 80 km/s and a time resolution of 50 spectra per binary orbit is achieved. We confirm that the observed spiral pattern in the disc of IP Pegasi can be reproduced by tidal density waves in the accretion disc and demands the presence of a large, hot disc, at least in the early outburst stages.

  11. Three-integral models for axisymmetric galactic discs

    E-Print Network [OSTI]

    B. Famaey; K. Van Caelenberg; H. Dejonghe

    2002-05-21T23:59:59.000Z

    We present new equilibrium component distribution functions that depend on three analytic integrals in a Stackel potential, and that can be used to model stellar discs of galaxies. These components are generalizations of two-integral ones and can thus provide thin discs in the two-integral approximation. Their most important properties are the partly analytical expression for their moments, the disc-like features of their configuration space densities (exponential decline in the galactic plane and finite extent in the vertical direction) and the anisotropy of their velocity dispersions. We further show that a linear combination of such components can fit a van der Kruit disc.

  12. Analysis of rabbit intervertebral disc physiology based on water metabolism. II. Changes in normal intervertebral discs under axial vibratory load

    SciTech Connect (OSTI)

    Hirano, N.; Tsuji, H.; Ohshima, H.; Kitano, S.; Itoh, T.; Sano, A.

    1988-11-01T23:59:59.000Z

    Metabolic changes induced by axial vibratory load to the spine were investigated based on water metabolism in normal intervertebral discs of rabbits with or without pentobarbital anesthesia. Tritiated water concentration in the intervertebral discs of unanesthetized rabbits was reduced remarkably by axial vibration for 30 minutes using the vibration machine developed for this study. Repeated vibratory load for 18 and 42 hours duration showed the recovery of /sup 3/H/sub 2/O concentration of the intervertebral disc without anesthesia. Computer simulation suggested a reduction of blood flow surrounding the intervertebral disc following the vibration stress. However, no reduction of the /sup 3/H/sub 2/O concentration in the intervertebral disc was noted under anesthesia. Emotional stress cannot be excluded as a factor in water metabolism in the intervertebral disc.

  13. Video Description Length Guided Constant Quality Video Coding with Bitrate Constraint

    E-Print Network [OSTI]

    Tomkins, Andrew

    Video Description Length Guided Constant Quality Video Coding with Bitrate Constraint Lei Yang propose a new video encoding strategy -- Video description length guided Constant Quality video coding with Bitrate Constraint (V-CQBC), for large scale video transcoding systems of video charing websites

  14. 2012 ARPA-E Energy Innovation Summit: Profiling Foro Energy: High Power Lasers - Long Distances (Performer Video)

    ScienceCinema (OSTI)

    None Available

    2012-03-21T23:59:59.000Z

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. A few videos were selected for showing during the Summit to attendees. These 'performer videos' highlight innovative research that is ongoing and related to the main topics of the Summit's sessions. Featured in this video from Foro Energy are Joel Moxley, Founder and CEO, Mark Zediker, Founder and CTO, and Paul Deutch, President and COO. Steven Chu, Secretary of Energy, also appears briefly in this video to praise the accomplishment of a high powered laser that can transmit that power long distances for faster and more powerful drilling of geothermal, oil, and gas wells.

  15. 2012 ARPA-E Energy Innovation Summit: Profiling Foro Energy: High Power Lasers - Long Distances (Performer Video)

    SciTech Connect (OSTI)

    None Available

    2012-02-28T23:59:59.000Z

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. A few videos were selected for showing during the Summit to attendees. These 'performer videos' highlight innovative research that is ongoing and related to the main topics of the Summit's sessions. Featured in this video from Foro Energy are Joel Moxley, Founder and CEO, Mark Zediker, Founder and CTO, and Paul Deutch, President and COO. Steven Chu, Secretary of Energy, also appears briefly in this video to praise the accomplishment of a high powered laser that can transmit that power long distances for faster and more powerful drilling of geothermal, oil, and gas wells.

  16. 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.

    E-Print Network [OSTI]

    Zhang, Meirong

    © 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved

  17. 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.

    E-Print Network [OSTI]

    Qian, Weihong

    © 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved

  18. 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.

    E-Print Network [OSTI]

    Zhang, Ke-Min

    © 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. #12;© 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved

  19. Far-infrared and sub-millimetre surveys of circumstellar discs

    E-Print Network [OSTI]

    Phillips, Neil Matthew

    2011-06-27T23:59:59.000Z

    . This thesis focuses on observational studies at far-infrared and sub-millimetre wavelengths of debris discs and the late stages of protoplanetary disc evolution. An overview of surveys for debris discs performed to date is presented, highlighting...

  20. accretion discs non-barotropic: Topics by E-print Network

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

    of a dwarf novae disc through its outburst cycle, from isolating the spectrum of a disc wind to revealing the geometry of disc spiral shocks. I end with an outline of the future...

  1. DISC1 & GSK3? modulate PDE4 activity: functional integration of psychiatric associated signalling pathways 

    E-Print Network [OSTI]

    Carlyle, Becky Catherine

    2010-01-01T23:59:59.000Z

    Following the discovery of the DISC1 gene in 2000, subsequent research has led to DISC1 becoming one of the most promising candidate genes for psychiatric disorders. Acting as a scaffold protein, DISC1 has a large number ...

  2. Discs Large Homolog 1: Identifying Molecular Mechanisms that Guide Functional Specificity in Lymphocytes

    E-Print Network [OSTI]

    Crocetti, Jillian Ann

    2014-01-01T23:59:59.000Z

    homolog of the Drosophila discs-large tumor suppressor. EMBOHumphries, L.A. & Miceli, M.C. Discs Large Homolog 1 (Dlg1)C. Shaw, W. Swat, B. Seed, Discs large (Dlg1) complexes in

  3. Self-regulated gravitational accretion in protostellar discs

    E-Print Network [OSTI]

    E. I. Vorobyov; S. Basu

    2007-09-13T23:59:59.000Z

    We present a numerical model for the evolution of a protostellar disc that has formed self-consistently from the collapse of a molecular cloud core. The global evolution of the disc is followed for several million years after its formation. The capture of a wide range of spatial and temporal scales is made possible by use of the thin-disc approximation. We focus on the role of gravitational torques in transporting mass inward and angular momentum outward during different evolutionary phases of a protostellar disc with disc-to-star mass ratio of order 0.1. In the early phase, when the infall of matter from the surrounding envelope is substantial, mass is transported inward by the gravitational torques from spiral arms that are a manifestation of the envelope-induced gravitational instability in the disc. In the late phase, when the gas reservoir of the envelope is depleted, the distinct spiral structure is replaced by ongoing irregular nonaxisymmetric density perturbations. The amplitude of these density perturbations decreases with time, though this process is moderated by swing amplification aided by the existence of the disc's sharp outer edge. Our global modelling of the protostellar disc reveals that there is typically a residual nonzero gravitational torque from these density perturbations, i.e. their effects do not exactly cancel out in each region. In particular, the net gravitational torque in the inner disc tends to be negative during first several million years of the evolution, while the outer disc has a net positive gravitational torque. Our global model of a self-consistently formed disc shows that it is also self-regulated in the late phase, so that it is near the Toomre stability limit, with a near-uniform Toomre parameter Q\\approx 1.5-2.0. (Abstract abridged).

  4. Home, Home (Video) on the Range: Reflections on Small-Town Video Stores in 2010

    E-Print Network [OSTI]

    Herbert, Daniel

    2010-01-01T23:59:59.000Z

    theory, and practices of video culture in the United States.Home, Home (Video) on the RangeReflections on Small-Town Video Stores in 2010 Daniel

  5. Secular evolution of viscous and self-gravitating circumstellar discs

    E-Print Network [OSTI]

    E. I. Vorobyov; Shantanu Basu

    2008-12-06T23:59:59.000Z

    We add the effect of turbulent viscosity via the \\alpha-prescription to models of the self-consistent formation and evolution of protostellar discs. Our models are non-axisymmetric and carried out using the thin-disc approximation. Self-gravity plays an important role in the early evolution of a disc, and the later evolution is determined by the relative importance of gravitational and viscous torques. In the absence of viscous torques, a protostellar disc evolves into a self-regulated state with disk-averaged Toomre parameter Q \\sim 1.5-2.0, non-axisymmetric structure diminishing with time, and maximum disc-to-star mass ratio \\xi = 0.14. We estimate an effective viscosity parameter \\alpha_eff associated with gravitational torques at the inner boundary of our simulation to be in the range 10^{-4}-10^{-3} during the late evolution. Addition of viscous torques with a low value \\alpha = 10^{-4} has little effect on the evolution, structure, and accretion properties of the disc, and the self-regulated state is largely preserved. A sequence of increasing values of \\alpha results in the discs becoming more axisymmetric in structure, being more gravitationally stable, having greater accretion rates, larger sizes, shorter lifetimes, and lower disc-to-star mass ratios. For \\alpha=10^{-2}, the model is viscous-dominated and the self-regulated state largely disappears by late times. (Abridged)

  6. Video2Text: Learning to Annotate Video Content Hrishikesh Aradhye

    E-Print Network [OSTI]

    Tomkins, Andrew

    , and description sections of these videos. In comparison, any hand-designed niche set of labels (e.g., porn, news

  7. Giant Planet Migration in Viscous Power-Law Discs

    E-Print Network [OSTI]

    R. G. Edgar

    2007-04-03T23:59:59.000Z

    Many extra-solar planets discovered over the past decade are gas giants in tight orbits around their host stars. Due to the difficulties of forming these `hot Jupiters' in situ, they are generally assumed to have migrated to their present orbits through interactions with their nascent discs. In this paper, we present a systematic study of giant planet migration in power law discs. We find that the planetary migration rate is proportional to the disc surface density. This is inconsistent with the assumption that the migration rate is simply the viscous drift speed of the disc. However, this result can be obtained by balancing the angular momentum of the planet with the viscous torque in the disc. We have verified that this result is not affected by adjusting the resolution of the grid, the smoothing length used, or the time at which the planet is released to migrate.

  8. T-551: Cisco Security Advisory: Multiple Cisco WebEx Player Vulnerabil...

    Office of Environmental Management (EM)

    51: Cisco Security Advisory: Multiple Cisco WebEx Player Vulnerabilities T-551: Cisco Security Advisory: Multiple Cisco WebEx Player Vulnerabilities February 7, 2011 - 7:56am...

  9. U-192: VMware Workstation/Player VM Remote Device Bug Lets Local...

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

    Player. PLATFORM: Version(s): Workstation 8.x, Player 4.x aBSTRACT: A local or remote user can cause denial of service conditions on the target virtual system. reference...

  10. T-545: RealPlayer Heap Corruption Error in 'vidplin.dll' Lets...

    Energy Savers [EERE]

    T-545: RealPlayer Heap Corruption Error in 'vidplin.dll' Lets Remote Users Execute Arbitrary Code T-545: RealPlayer Heap Corruption Error in 'vidplin.dll' Lets Remote Users Execute...

  11. V-228: RealPlayer Buffer Overflow and Memory Corruption Error...

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

    were reported in RealPlayer PLATFORM: RealPlayer 16.0.2.32 and prior ABSTRACT: A remote user can cause arbitrary code to be executed on the target user's system REFERENCE...

  12. V-049: RealPlayer Buffer Overflow and Invalid Pointer Flaw Let...

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

    RealPlayer Buffer Overflow and Invalid Pointer Flaw Let Remote Users Execute Arbitrary Code PLATFORM: Windows RealPlayer 15.0.6.14 and prior. ABSTRACT: Two vulnerabilities were...

  13. Modeling player self-representation in multiplayer online games using social network data

    E-Print Network [OSTI]

    Lim, Chong-U

    2013-01-01T23:59:59.000Z

    Game players express values related to self-expression through various means such as avatar customization, gameplay style, and interactions with other players. Multiplayer online games are now often integrated with social ...

  14. NREL: Biomass Research - Video Text

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

    common corn grain ethanol. Cellulosic ethanol is made from organic plant matter called biomass. The video shows different forms of biomass such as switchgrass, corn stalks, and...

  15. 2014 Modern Power Grid Video

    SciTech Connect (OSTI)

    None

    2014-06-02T23:59:59.000Z

    A video from NETL that describes the details of a modern power grid and how it can help our nation save on energy costs.

  16. 2014 Modern Power Grid Video

    ScienceCinema (OSTI)

    None

    2014-07-22T23:59:59.000Z

    A video from NETL that describes the details of a modern power grid and how it can help our nation save on energy costs.

  17. New research, publications and videos

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

    New research, publications and videos Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:March 2015 All Issues submit New research, publications...

  18. Video Resources on Geothermal Technologies

    Broader source: Energy.gov [DOE]

    Geothermal video offerings at the Department of Energy include simple interactive illustrations of geothermal power technologies and interviews on initiatives in the Geothermal Technologies Office.

  19. Video Production Checklist Gear needed

    E-Print Network [OSTI]

    Jacobs, Laurence J.

    Video Production Checklist Gear needed: · Camera · Tripod · Headphones · Microphone · Memory cards (sunlight, tungsten, fluorescent, etc.) Camera should have an auto white balance setting. · Mic the person

  20. Graduate Student Video Contest: Guidelines and

    E-Print Network [OSTI]

    Thomas, Andrew

    GRAD TALKS Graduate Student Video Contest: Guidelines and Submission Information The UMaine Graduate School solicits video submissions for the first Graduate Student video contest. The contest and one video as part of the contest. Videos should be 2 minutes (120 seconds) long and should explain

  1. Integrated video communication with Nicolas Roussel

    E-Print Network [OSTI]

    Integrated video communication with videoSpace Nicolas Roussel Laboratoire de Recherche en for collaboration with the user's existing computer environment. This demonstration presents videoSpace, a software toolkit that facilitates the integration of live video into documents and applications. Introduction Video

  2. In 2010 a group of key forestry players

    E-Print Network [OSTI]

    Forestry Skills Action Plan #12;Summary #12;In 2010 a group of key forestry players came together to start a movement across the sector to upskill the current, and train the future, forestry workforce. #12;In May 2010 Forestry Commission England convened a small cross- sector task and finish group

  3. Sandia Energy - Videos

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol Home DistributionTransportation Safety Home StationaryUpper RioVideos Home EC

  4. Video:Brian Taylor

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1 - USAFofEmail Mr. WilliamVideo: Watch the Open

  5. Video:Colleen Iversen

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1 - USAFofEmail Mr. WilliamVideo: Watch the Open

  6. Bisfuel links - Video

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccess Stories Site MapSolar energy newsVideo

  7. Bayesian Modeling Of An Human MMORPG Player Gabriel Synnaevea,c

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -run factions fighting each other but we modeled a particular domain of multiplayer RPG called players versus

  8. Video Switching in the Panopto Editor Video Switching in the Panopto Editor

    E-Print Network [OSTI]

    Benos, Panayiotis "Takis"

    Video Switching in the Panopto Editor Video Switching in the Panopto Editor In My Pitt Video (Panopto) you can control and edit which video streams the viewer sees by editing individual streams in the My Pitt Video (Panopto) Editor. Editing the primary video source will edit on all streams, editing

  9. MODELING OF VIDEO OBJECTS IN A VIDEO DATABASES Lei Chen and M. Tamer Ozsu

    E-Print Network [OSTI]

    Özsu, M. Tamer

    MODELING OF VIDEO OBJECTS IN A VIDEO DATABASES Lei Chen and M. Tamer ¨Ozsu School of Computer an efficient video data model to represent moving trajectories of video objects and spatio- temporal relationships among the video objects. A video clips is segmented into a set of common appearance inter- vals

  10. Object-Video Streams for Preserving Privacy in Video Surveillance Faisal Z. Qureshi

    E-Print Network [OSTI]

    Qureshi, Faisal Z.

    Object-Video Streams for Preserving Privacy in Video Surveillance Faisal Z. Qureshi Faculty--This paper presents a framework for preserving privacy in video surveillance. Raw video is decomposed into a background and one or more object-video streams. Object- video streams can be combined to render the scene

  11. A Memory-Based Approach to Two-Player Texas Hold'em

    E-Print Network [OSTI]

    Goodman, James R.

    comes Jimmy who only ever plays Paper #12;Rock-Paper-Scissors Example The Nash player will continue Jimmy #12;Rock-Paper-Scissors Example However, because we know Jimmy's strategy an exploitive player Jimmy at every decision point Now, against Jimmy the exploitive player will win - Consequence

  12. Photoevaporation of protoplanetary discs II: evolutionary models and observable properties

    E-Print Network [OSTI]

    R. D. Alexander; C. J. Clarke; J. E. Pringle

    2006-03-09T23:59:59.000Z

    We present a new model for protoplanetary disc evolution. This model combines viscous evolution with photoevaporation of the disc, in a manner similar to Clarke, Gendrin & Sotomayor (2001). However in a companion paper (Alexander, Clarke & Pringle 2006a) we have shown that at late times such models must consider the effect of stellar radiation directly incident on the inner disc edge, and here we model the observational implications of this process. We find that the entire disc is dispersed on a time-scale of order $10^5$yr after a disc lifetime of a few Myr, consistent with observations of T Tauri (TT) stars. We use a simple prescription to model the spectral energy distribution of the evolving disc, and demonstrate that the model is consistent with observational data across a wide range of wavelengths. We note also that the model predicts a short ``inner hole'' phase in the evolution of all TT discs, and make predictions for future observations at mid-infrared and millimetre wavelengths.

  13. Does the stellar disc flattening depend on the galaxy type?

    E-Print Network [OSTI]

    Mosenkov, A V; Reshetnikov, V P; Bizyaev, D V; Kautsch, S J

    2015-01-01T23:59:59.000Z

    We analyze the dependence of the stellar disc flatness on the galaxy morphological type using 2D decomposition of galaxies from the reliable subsample of the Edge-on Galaxies in SDSS (EGIS) catalogue. Combining these data with the retrieved models of the edge-on galaxies from the Two Micron All Sky Survey (2MASS) and the Spitzer Survey of Stellar Structure in Galaxies (S$^4$G) catalogue, we make the following conclusions: (1) The disc relative thickness $z_0/h$ in the near- and mid-infrared passbands correlates weakly with morphological type and does not correlate with the bulge-to-total luminosity ratio $B/T$ in all studied bands. (2) Applying an 1D photometric profile analysis overestimates the disc thickness in galaxies with large bulges making an illusion of the relationship between the disc flattening and the ratio $B/T$. (3) In our sample the early-type disc galaxies (S0/a) have both flat and "puffed" discs. The early spirals and intermediate-type galaxies have a large scatter of the disc flatness, whic...

  14. Musical form in non-narrative video

    E-Print Network [OSTI]

    Sebring, Ellen Irene

    1986-01-01T23:59:59.000Z

    "Musical Form in Non- Narrative Video" explores musical structure as a model for visual form over time, specifically in the creation of artistic video. Video is a medium in which sound and image coexist at the source as ...

  15. PowerPoints, Video Lessons and Outlines

    E-Print Network [OSTI]

    Lesson 1 Video · Lesson 1 Outline ... Lesson 2 Video · Lesson 2 Outline. 9/1. Labor Day. No Classes. 9/2. 9/3. Lesson 3 PowerPoint · Lesson 3 Video · Lesson 3 ...

  16. Six Musical Compositions Integrating Digital Video

    E-Print Network [OSTI]

    Bultmann, Nils Patrick

    2013-01-01T23:59:59.000Z

    2 Take 1 Multi-track Recording +4 tracks of video Take 1 setinto 4 way splitscreen video set into google maps Take 1Essential Supporting Videos The following Essential

  17. Video Games: A Site for Sore Eyes

    E-Print Network [OSTI]

    Mozaffari, Sahar

    2011-01-01T23:59:59.000Z

    1984). Rx for lazy eye: Video game exercise. Science News,patients. Here we have seen video games used for amblyopia,function through action video game training. Nature

  18. Video Stores, Media Technologies, and Memory

    E-Print Network [OSTI]

    Wilken, Rowan

    2010-01-01T23:59:59.000Z

    Deb Verhoeven, “Film, Video, DVD and Media Fields Journal133-154. 17 Paul McDonald, Video and DVD Industries (London:BFI, 2007). 18 McDonald, Video and DVD Industries, 109. 19

  19. Prioritized Packet Fragmentation for H.264 Video

    E-Print Network [OSTI]

    Kambhatla, K R; Kumar, S; Cosman, P

    2011-01-01T23:59:59.000Z

    issue on Emerging H.264/AVC Video Coding Standard, vol. 17,mechanism to improve H.264 video transmis- sion over wlans,”Leung, and Y. P. Fallah, “Video packetization techniques for

  20. Video looping of human cyclic motion

    E-Print Network [OSTI]

    Choi, Hye Mee

    2004-09-30T23:59:59.000Z

    In this thesis, a system called Video Looping is developed to analyze human cyclic motions. Video Looping allows users to extract human cyclic motion from a given video sequence. This system analyzes similarities from a large amount of live footage...

  1. Lindblad resonance torques in relativistic discs: I. Basic equations

    E-Print Network [OSTI]

    Christopher M. Hirata

    2011-03-01T23:59:59.000Z

    Lindblad resonances have been suggested as an important mechanism for angular momentum transport and heating in discs in binary black hole systems. We present the basic equations for the torque and heating rate for relativistic thin discs subjected to a perturbation. The Lindblad resonance torque is written explicitly in terms of metric perturbations for an equatorial disc in a general axisymmetric, time-stationary spacetime with a plane of symmetry. We show that the resulting torque formula is gauge-invariant. Computations for the Schwarzschild and Kerr spacetimes are presented in the companion paper.

  2. Critical Materials Workshop Plenary Session Videos | Department...

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

    Critical Materials Workshop Plenary Session Videos Critical Materials Workshop Plenary Session Videos Welcome and Overview of Workshop and Energy Innovation Hubs Speakers * Dr. Leo...

  3. Video Lessons, PowerPoints, and Outlines

    E-Print Network [OSTI]

    POWERPOINT PRESENTATIONS, VIDEO LESSONS AND OUTLINES ... 6/11. Lesson 1 PowerPoint (Part A) · Lesson 1 PowerPoint (Part B) · Lesson 1 Video.

  4. Dynamic Bayesian networks for the classification of spinning discs

    E-Print Network [OSTI]

    Schmidt, Aurora Clare, 1981-

    2004-01-01T23:59:59.000Z

    This thesis considers issues for the application of particle filters to a class of nonlinear filtering and classification problems. Specifically, we study a prototype system of spinning discs. The system combines linear ...

  5. The structure of protoplanetary discs around evolving young stars

    E-Print Network [OSTI]

    Bitsch, Bertram; Lambrechts, Michiel; Morbidelli, Alessandro

    2014-01-01T23:59:59.000Z

    The formation of planets with gaseous envelopes takes place in protoplanetary accretion discs on time-scales of several millions of years. Small dust particles stick to each other to form pebbles, pebbles concentrate in the turbulent flow to form planetesimals and planetary embryos and grow to planets, which undergo substantial radial migration. All these processes are influenced by the underlying structure of the protoplanetary disc, specifically the profiles of temperature, gas scale height and density. The commonly used disc structure of the Minimum Mass Solar Nebular (MMSN) is a simple power law in all these quantities. However, protoplanetary disc models with both viscous and stellar heating show several bumps and dips in temperature, scale height and density caused by transitions in opacity, which are missing in the MMSN model. These play an important role in the formation of planets, as they can act as sweet spots for the formation of planetesimals via the streaming instability and affect the direction...

  6. Spiral density waves in the outer galactic gaseous discs

    E-Print Network [OSTI]

    Khoperskov, S A

    2015-01-01T23:59:59.000Z

    Deep HI observations of the outer parts of disc galaxies demonstrate the frequent presence of extended, well-developed spiral arms far beyond the optical radius. To understand the nature and the origin of such outer spiral structure, we investigate the propagation in the outer gaseous disc of large-scale spiral waves excited in the bright optical disc. Using hydrodynamical simulations, we show that non-axisymmetric density waves, penetrating in the gas through the outer Lindblad resonance, can exhibit relatively regular spiral structures outside the bright optical stellar disc. For low-amplitude structures, the results of numerical simulations match the predictions of a simple WKB linear theory. The amplitude of spiral structure increases rapidly with radius. Beyond $\\approx 2$ optical radii, spirals become nonlinear (the linear theory becomes quantitatively and qualitatively inadequate) and unstable to Kelvin-Helmholtz instability. In numerical simulations, in models for which gas is available very far out, ...

  7. accretion disc plasmas: Topics by E-print Network

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

    should give insight into the magnetic dynamics of accretion discs and jets. A high-speed multiple-frame CCD camera reveals images of the formation and helical instability of a...

  8. accretion disc theory: Topics by E-print Network

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

    we conjecture that the limiting field strength for a thin disc is such that the Alfven speed roughly equals the geometric mean of the Keplerian speed and the gas sound speed. We...

  9. accretion disc models: Topics by E-print Network

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

    we conjecture that the limiting field strength for a thin disc is such that the Alfven speed roughly equals the geometric mean of the Keplerian speed and the gas sound speed. We...

  10. accretion disc model: Topics by E-print Network

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

    we conjecture that the limiting field strength for a thin disc is such that the Alfven speed roughly equals the geometric mean of the Keplerian speed and the gas sound speed. We...

  11. attenuating disc wind: Topics by E-print Network

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

    point located at (x,z)(0,-d) and (ii) streamlines that emerge at a constant inclination angle from the disc midplane (the x-axis, as we consider geometrically thin...

  12. Noncommutative Field Theory: Numerical Analysis with the Fuzzy Disc

    E-Print Network [OSTI]

    Fedele Lizzi; Bernardino Spisso

    2012-07-28T23:59:59.000Z

    The fuzzy disc is a discretization of the algebra of functions on the two dimensional disc using finite matrices which preserves the action of the rotation group. We define a $\\varphi^4$ scalar field theory on it and analyze numerically for three different limits for the rank of the matrix going to infinity. The numerical simulations reveal three different phases: uniform and disordered phases already the present in the commutative scalar field theory and a nonuniform ordered phase as a noncommutative effects. We have computed the transition curves between phases and their scaling. This is in agreement with studies on the fuzzy sphere, although the speed of convergence for the disc seems to be better. We have performed also three the limits for the theory in the cases of the theory going to the commutative plane or commutative disc. In this case the theory behaves differently, showing the intimate relationship between the nonuniform phase and noncommutative geometry.

  13. The precession of eccentric discs in close binaries

    E-Print Network [OSTI]

    James R. Murray

    1999-11-25T23:59:59.000Z

    We consider the precession rates of eccentric discs in close binaries, and compare theoretical predictions with the results of numerical disc simulations and with observed superhump periods. A simple dynamical model for precession is found to be inadequate. For mass ratios less than approximately 1/4 a linear dynamical model does provide an upper limit for disc precession rates. Theory suggests that pressure forces have a significant retrograde impact upon the precession rate (Lubow 1992). We find that the disc precession rates for three systems with accurately known mass ratios are significantly slower than predicted by the dynamical theory, and we attribute the difference to pressure forces. By assuming that pressure forces of similar magnitude occur in all superhumping systems, we obtain an improved fit to superhump observations.

  14. The instantaneous radial growth rate of stellar discs

    E-Print Network [OSTI]

    Pezzulli, Gabriele; Boissier, Samuel; Muńoz-Mateos, Juan Carlos

    2015-01-01T23:59:59.000Z

    We present a new and simple method to measure the instantaneous mass and radial growth rates of the stellar discs of spiral galaxies, based on their star formation rate surface density (SFRD) profiles. Under the hypothesis that discs are exponential with time-varying scalelengths, we derive a universal theoretical profile for the SFRD, with a linear dependence on two parameters: the specific mass growth rate $\

  15. VideoSTAR (Video STorage And Retrieval) is an experimental database frame-work for video information management. The development of this framework

    E-Print Network [OSTI]

    ABSTRACT VideoSTAR (Video STorage And Retrieval) is an experimental database frame- work for video of traditional video tape archives are facing and by the multimedia technology that makes integrated, digital video archives feasible. Speci cally, VideoSTAR addresses issues related to sharing of video information

  16. Electromagnetic counterparts from counter-rotating relativistic kicked discs

    E-Print Network [OSTI]

    Olindo Zanotti

    2011-08-23T23:59:59.000Z

    We show the results of two dimensional general relativistic inviscid and isothermal hydrodynamical simulations comparing the behavior of co-rotating (with respect to the black hole rotation) and counter-rotating circumbinary quasi-Keplerian discs in the post merger phase of a supermassive binary black hole system. While confirming the spiral shock generation within the disc due to the combined effects of mass loss and recoil velocity of the black hole, we find that the maximum luminosity of counter-rotating discs is a factor ~(2-12) higher than in the co-rotating case, depending on the spin of the black hole. On the other hand, the luminosity peak happens ~10 days later with respect to the co-rotating case, for a binary with a total mass M~10^6 M_\\odot. Although the global dynamics of counter-rotating discs in the post merger phase of a merging event is very similar to that for co-rotating discs, an important difference has been found. In fact, increasing the spin of the central black hole produces more luminous co-rotating discs while less luminous counter-rotating ones.

  17. Wakes of ram pressure stripped disc galaxies

    E-Print Network [OSTI]

    Roediger, E; Hoeft, M

    2006-01-01T23:59:59.000Z

    Spiral galaxies that move through the intracluster medium lose a substantial amount of their gas discs due to ram pressure stripping. The recent observations of NGC 4388 by Oosterloo & van Gorkom 2005 reveal a tail of stripped gas of ~ 100 kpc behind the source galaxy. We present first 3D hydrodynamical simulations of the evolution of such ram pressure stripped tails. We find that if the ICM wind does not vary significantly over a period of a few 100 Myr, subsonic galaxies produce a tail with regular features similar to a von-Karman vortex street. In this case, the tail widens systematically by about 45 kpc per 100 kpc distance behind the source galaxy. The widening rate is independent of the galaxy's inclination for a large range of inclinations. For supersonic galaxies, the tail is more irregular than for subsonic ones. The tail observed for NGC 4388 is narrower than the tails in our simulations. Reasons for this difference may be additional physical processes such as heat conduction or viscosity. In ad...

  18. Wakes of ram pressure stripped disc galaxies

    E-Print Network [OSTI]

    E. Roediger; M. Brueggen; M. Hoeft

    2006-03-21T23:59:59.000Z

    Spiral galaxies that move through the intracluster medium lose a substantial amount of their gas discs due to ram pressure stripping. The recent observations of NGC 4388 by Oosterloo & van Gorkom 2005 reveal a tail of stripped gas of ~ 100 kpc behind the source galaxy. We present first 3D hydrodynamical simulations of the evolution of such ram pressure stripped tails. We find that if the ICM wind does not vary significantly over a period of a few 100 Myr, subsonic galaxies produce a tail with regular features similar to a von-Karman vortex street. In this case, the tail widens systematically by about 45 kpc per 100 kpc distance behind the source galaxy. The widening rate is independent of the galaxy's inclination for a large range of inclinations. For supersonic galaxies, the tail is more irregular than for subsonic ones. The tail observed for NGC 4388 is narrower than the tails in our simulations. Reasons for this difference may be additional physical processes such as heat conduction or viscosity. In addition, we conclude that the observed S-shape of this tail is not due to von Karman oscillations, because this galaxy is likely to move supersonically. A reason for the observed shape may be motions in the ambient ICM. Finally, we discuss implications for the distribution of metals in the ICM due to ram pressure stipping.

  19. Perceptual quality assessment for compressed video

    E-Print Network [OSTI]

    Yang, Kai-Chieh

    2007-01-01T23:59:59.000Z

    5 Perceptual Temporal Quality Metric (Frame Interpolation Quality Metric . . . . . . . . . . . .Overview of Video Quality Assessment . . . . . . . . . . . .

  20. Video Textures Arno Schodl1,2

    E-Print Network [OSTI]

    Meenakshisundaram, Gopi

    Video Textures Arno Sch¨odl1,2 Richard Szeliski2 David H. Salesin2,3 Irfan Essa1 1 Georgia type of medium, called a video texture, which has qualities somewhere between those of a photograph and a video. A video texture provides a continuous infinitely varying stream of images. While the individual

  1. Video Indexing Based on Mosaic Representations

    E-Print Network [OSTI]

    Shapiro, Ehud

    1 Video Indexing Based on Mosaic Representations Michal Irani P. Anandan Abstract| Video is a rich is implicitly buried inside the raw video data, and is provided with the cost of very high temporal redundancy. While the standard sequential form of video storage is ad- equate for viewing in a "movie mode

  2. Get Started with Video Captioning

    E-Print Network [OSTI]

    Engine Optimization (SEO), which may give you a leg up on your competition. · Captioned video also opens if they so choose. Search Engine Optimization (SEO) Search Engine Optimization (SEO) is a key aspect of inter

  3. Multimedia-Video for Learning

    E-Print Network [OSTI]

    Chua, Kah Hean; Wee, Loo Kang; Tan, Ching

    2015-01-01T23:59:59.000Z

    Multimedia engages an audience through a combination of text, audio, still images, animation, video, or interactivity-based content formats. Along this vein, free platforms have been seen to allow budding enthusiasts to create multimedia content. For example, Google sites (Wee, 2012b) offer creative opportunities in website development that enable text insertion, still image, video and animation embedding, along with audio and hyper-interactive links to simulations (Christian & Esquembre, 2012; Wee, 2013; Wee, Goh, & Chew, 2013; Wee, Goh, & Lim, 2013; Wee, Lee, Chew, Wong, & Tan, 2015). This chapter focuses on the video aspect of multimedia, which can be positioned as a component to any effective self-paced on-line lesson that would be available anytime, anywhere via computer or mobile devices. The multimedia video approach aims to help users overcome barriers in creating engaging, effective and meaningful content (Barron & Darling-Hammond, 2008) for teaching and learning in an online envi...

  4. Transcript for Building America Video

    Broader source: Energy.gov [DOE]

    Transcript of a video about how DOE’s Building America program is helping to bridge the gap between homes with high energy costs and homes that are healthy, durable, and energy efficient.

  5. What We Do Spatial Video Geospatial video, also known as mobile mapping or

    E-Print Network [OSTI]

    Sheridan, Scott

    What We Do Spatial Video Geospatial video, also known as mobile mapping or spatial video, is an emerging technology that combines Global Positioning Systems (GPS) with video. This approach enables illustrates the part of Colorado Springs, Colorado in which spatially-encoded video data were collected

  6. H.264 video watermarking -Marc Chaumont -IPTA'2010 H.264 video watermarking

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    H.264 video watermarking - Marc Chaumont - IPTA'2010 H.264 video watermarking: applications and Applications, Paris : France (2010)" #12;H.264 video watermarking - Marc Chaumont - IPTA'2010 Preamble Outline 1 Preamble 2 H.264 3 Watermarking Definitions Video watermarking Security of video watermarking

  7. Video Communications Systems 2 LifeSize Video Communications Systems User Guide

    E-Print Network [OSTI]

    LifeSize® Video Communications Systems User Guide #12;2 LifeSize Video Communications Systems User-9301 #12;LifeSize Video Communications Systems User Guide 3 Welcome to LifeSize Video Communications Systems LifeSize high definition video communications systems enable anyone with dispersed colleagues

  8. Restoration of disc height through non-invasive spinal decompression is associated with decreased discogenic low back pain: a retrospective cohort study

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    in reduction of lumbar disc prolapse by traction. Arch Physeffect of traction on lumbar disc herniations. Spine 1989,Innervation of "painful" lumbar discs. Spine 1997, 22:2342-

  9. Nuclear stellar discs in early-type galaxies --- II. Photometric properties

    E-Print Network [OSTI]

    Cecilia Scorza; Frank C. van den Bosch

    1998-06-04T23:59:59.000Z

    Hubble Space Telescope images of two early-type galaxies harboring both nuclear and outer stellar discs are studied in detail. By means of a photometric decomposition, the images of NGC 4342 and NGC 4570 are analyzed and the photometric properties of the nuclear discs investigated. We find a continuity of properties in the parameter space defined by the central surface brightness and the scalelength of discs in spirals, S0s and embedded discs in ellipticals, in the sense that the nuclear discs extend the observed disc properties even further towards smaller scalelengths and brighter central surface brightnesses. When including the nuclear discs, disc properties span more than four orders of magnitude in both scalelength and central surface brightness. The nuclear discs studied here are the smallest and brightest stellar discs known, and as such, they are as extreme in their photometric properties as Malin I, when compared to typical galactic discs that obey Freeman's law. We discuss a possible formation scenario in which the double-disc structure observed in these galaxies has been shaped by now dissolved bars. Based on the fact that the black holes known to exist in some of these galaxies have masses comparable to those of the nuclear discs, we explore a possible link between the black holes and the nuclear discs.

  10. How to play a disc brake

    E-Print Network [OSTI]

    Oleg N. Kirillov

    2007-08-22T23:59:59.000Z

    We consider a gyroscopic system under the action of small dissipative and non-conservative positional forces, which has its origin in the models of rotating bodies of revolution being in frictional contact. The spectrum of the unperturbed gyroscopic system forms a "spectral mesh" in the plane "frequency -gyroscopic parameter" with double semi-simple purely imaginary eigenvalues at zero value of the gyroscopic parameter. It is shown that dissipative forces lead to the splitting of the semi-simple eigenvalue with the creation of the so-called "bubble of instability" - a ring in the three-dimensional space of the gyroscopic parameter and real and imaginary parts of eigenvalues, which corresponds to complex eigenvalues. In case of full dissipation with a positive-definite damping matrix the eigenvalues of the ring have negative real parts making the bubble a latent source of instability because it can "emerge" to the region of eigenvalues with positive real parts due to action of both indefinite damping and non-conservative positional forces. In the paper, the instability mechanism is analytically described with the use of the perturbation theory of multiple eigenvalues. As an example stability of a rotating circular string constrained by a stationary load system is studied in detail. The theory developed seems to give a first clear explanation of the mechanism of self-excited vibrations in the rotating structures in frictional contact, that is responsible for such well-known phenomena of acoustics of friction as the squealing disc brake and the singing wine glass.

  11. The Video Mesh: A Data Structure for Image-based Video Editing

    E-Print Network [OSTI]

    Durand, Fredo

    2009-12-16T23:59:59.000Z

    This paper introduces the video mesh, a data structure for representing video as 2.5D "paper cutouts." The video mesh allows interactive editing of moving objects and modeling of depth, which enables 3D effects and ...

  12. The Video Mesh: A Data Structure for Image-based Three-dimensional Video Editing

    E-Print Network [OSTI]

    Chen, Jiawen

    This paper introduces the video mesh, a data structure for representing video as 2.5D “paper cutouts.” The video mesh allows interactive editing of moving objects and modeling of depth, which enables 3D effects and ...

  13. Understanding in-video dropouts and interaction peaks in online lecture videos

    E-Print Network [OSTI]

    Guo, Philip J.

    With thousands of learners watching the same online lecture videos, analyzing video watching patterns provides a unique opportunity to understand how students learn with videos. This paper reports a large-scale analysis ...

  14. Oscillations of Thick Accretion Discs Around Black Holes - II

    E-Print Network [OSTI]

    Eduardo Rubio-Herrera; William H. Lee

    2005-05-21T23:59:59.000Z

    We present a numerical study of the global modes of oscillation of thick accretion discs around black holes. We have previously studied the case of constant distributions of specific angular momentum. In this second paper, we investigate (i) how the size of the disc affects the oscillation eigenfrequencies, and (ii) the effect of power-law distributions of angular momentum on the oscillations. In particular, we compare the oscillations of the disc with the epicyclic eigenfrequencies of a test particle with different angular momentum distributions orbiting around the central object. We find that there is a frequency shift away from the epicyclic eigenfrequency of the test particle to lower values as the size of the tori is increased. We have also studied the response of a thick accretion disc to a localized external perturbation using non constant specific angular momentum distributions within the disc. We find that in this case it is also possible (as reported previously for constant angular momentum distributions) to efficiently excite internal modes of oscillation. In fact we show here that the local perturbations excite global oscillations (acoustic p modes) closely related to the epicyclic oscillations of test particles. Our results are particularly relevant in the context of low mass X-ray binaries and microquasars, and the high frequency Quasi-Periodic Oscillations (QPOs) observed in them. Our computations make use of a Smooth Particle Hydrodynamics (SPH) code in azimuthal symmetry, and use a gravitational potential that mimics the effects of strong gravity.

  15. Silicate features in Galactic and extragalactic post-AGB discs

    E-Print Network [OSTI]

    Gielen, C; Van Winckel, H; Evans, T Lloyd; Woods, P M; Kemper, F; Marengo, M; Meixner, M; Sloan, G C; Tielens, A G G M

    2011-01-01T23:59:59.000Z

    Aims. In this paper we study the Spitzer and TIMMI2 infrared spectra of post-AGB disc sources, both in the Galaxy and the LMC. Using the observed infrared spectra we determine the mineralogy and dust parameters of the discs, and look for possible differences between the Galactic and extragalactic sources. Methods. Modelling the full spectral range observed allows us to determine the dust species present in the disc and different physical parameters such as grain sizes, dust abundance ratios, and the dust and continuum temperatures. Results. We find that all the discs are dominated by emission features of crystalline and amorphous silicate dust. Only a few sample sources show features due to CO2 gas or carbonaceous molecules such as PAHs and C60 fullerenes. Our analysis shows that dust grain processing in these discs is strong, resulting in large average grain sizes and a very high crystallinity fraction. However, we do not find any correlations between the derived dust parameters and properties of the central...

  16. Black hole mergers: do gas discs lead to spin alignment?

    E-Print Network [OSTI]

    Giuseppe Lodato; Davide Gerosa

    2012-11-01T23:59:59.000Z

    In this Letter we revisit arguments suggesting that the Bardeen-Petterson effect can coalign the spins of a central supermassive black hole binary accreting from a circumbinary (or circumnuclear) gas disc. We improve on previous estimates by adding the dependence on system parameters, and noting that the nonlinear nature of warp propagation in a thin viscous disc affects alignment. This reduces the disc's ability to communicate the warp, and can severely reduce the effectiveness of disc-assisted spin alignment. We test our predictions with a Monte Carlo realization of random misalignments and accretion rates and we find that the outcome depends strongly on the spin magnitude. We estimate a generous upper limit to the probability of alignment by making assumptions which favour it throughout. Even with these assumptions, about 40% of black holes with $a \\gtrsim 0.5$ do not have time to align with the disc. If the residual misalignment is not small and it is maintained down to the final coalescence phase this can give a powerful recoil velocity to the merged hole. Highly spinning black holes are thus more likely of being subject to strong recoils, the occurrence of which is currently debated.

  17. U-166: Adobe Shockwave Player Memory Corruption Flaws Let Remote Users Execute Arbitrary Code

    Broader source: Energy.gov [DOE]

    Multiple vulnerabilities were reported in Adobe Shockwave Player. A remote user can cause arbitrary code to be executed on the target user's system.

  18. Dispersion in the lifetime and accretion rate of T Tauri discs

    E-Print Network [OSTI]

    Philip J. Armitage; Cathie J. Clarke; Francesco Palla

    2003-03-14T23:59:59.000Z

    We compare evolutionary models for protoplanetary discs that include disc winds with observational determinations of the disc lifetime and accretion rate in Taurus. Using updated estimates for stellar ages in Taurus, together with published classifications, we show that the evolution of the disc fraction with stellar age is similar to that derived for ensembles of stars within young clusters. Around 30 percent of stars lose their discs within 1 Myr, while the remainder have disc lifetimes that are typically in the 1-10 Myr range. We show that the latter range of ages is consistent with theoretical models for disc evolution, provided that there is a dispersion of around 0.5 in the log of the initial disc mass. The same range of initial conditions brackets the observed variation in the accretion rate of Classical T Tauri stars at a given age. We discuss the expected lifetime of discs in close binary systems, and show that our models predict that the disc lifetime is almost constant for separations exceeding 10 au. This implies a low predicted fraction of binaries that pair a Classical T Tauri star with a Weak-lined T Tauri star, and is in better agreement with observations of the disc lifetime in binaries than disc models that do not include disc mass loss in a wind.

  19. Packet loss visibility and packet prioritization in digital videos

    E-Print Network [OSTI]

    Kanumuri, Sandeep

    2006-01-01T23:59:59.000Z

    Performance comparison for videos with apparent compres-Prioritization in Digital Videos A Dissertation submitted inloss visibility,” Packet Video Workshop, Irvine, December

  20. VIDEO PRESENTATION AND COMPRESSION Borko Furht and Raymond Westwater

    E-Print Network [OSTI]

    Furht, Borko

    9 VIDEO PRESENTATION AND COMPRESSION Borko Furht and Raymond Westwater Florida Atlantic University........................................................................................................................ 172 1.1 VIDEO REPRESENTATION AND FORMATS.................................................................................. 172 1.2 VIDEO INFORMATION UNITS

  1. Modeling packet-loss visibility in MPEG-2 video

    E-Print Network [OSTI]

    Kanumuri, S.; Cosman, P. C.; Reibman, A. R.; Vaishampayan, V. A.

    2006-01-01T23:59:59.000Z

    the design of an objective video fidelity metric,” in Proc.Quality moni- toring of video over a packet network,” IEEEevaluation of compressed video with severe distortions,” in

  2. Learning Statistics Using Motivational Videos, Real Data and Free Software

    E-Print Network [OSTI]

    Harraway, John A

    2012-01-01T23:59:59.000Z

    lessons associated with each video; the nineteen researchersAll Odds: Inside Statistics. Video Series Produced by COMAPStatistics Using Motivational Videos, Real Data and Free

  3. Accretion Discs Around Black Holes: Developement of Theory

    E-Print Network [OSTI]

    G. S. Bisnovatyi-Kogan

    1999-11-11T23:59:59.000Z

    Standard accretion disk theory is formulated which is based on the local heat balance. The energy produced by a turbulent viscous heating is supposed to be emitted to the sides of the disc. Sources of turbulence in the accretion disc are connected with nonlinear hydrodynamic instability, convection, and magnetic field. In standard theory there are two branches of solution, optically thick, and optically thin. Advection in accretion disks is described by the differential equations what makes the theory nonlocal. Low-luminous optically thin accretion disc model with advection at some suggestions may become advectively dominated, carrying almost all the energy inside the black hole. The proper account of magnetic filed in the process of accretion limits the energy advected into a black hole, efficiency of accretion should exceed $\\sim 1/4$ of the standard accretion disk model efficiency.

  4. Constraints on AGN accretion disc viscosity derived from continuum variability

    E-Print Network [OSTI]

    Rhaana L. C. Starling; Aneta Siemiginowska; Phil Uttley; Roberto Soria

    2003-09-10T23:59:59.000Z

    We estimate a value of the viscosity parameter in AGN accretion discs for the PG quasar sample. We assume that optical variability on time-scales of months to years is caused by local instabilities in the inner accretion disc. Comparing the observed variability time-scales to the thermal time-scales of alpha-disc models we obtain constraints on the viscosity parameter for the sample. We find that, at a given L/L_Edd, the entire sample is consistent with a single value of the viscosity parameter, alpha. We obtain constraints of 0.01 < alpha < 0.03 for 0.01 < L/L_Edd < 1.0. This narrow range suggests that these AGN are all seen in a single state, with a correspondingly narrow spread of black hole masses or accretion rates. The value of alpha we derive is consistent with predictions by current simulation s in which MHD turbulence is the primary viscosity mechanism.

  5. Some challenges and directions for next generation accretion disc theory

    E-Print Network [OSTI]

    Blackman, Eric G

    2015-01-01T23:59:59.000Z

    Accretion disc theory is far less developed than that of stellar evolution, although a similarly mature phenomenological picture is ultimately desired. While conceptual progress from the interplay of theory and numerical simulations has amplified awareness of the role of magnetic fields in angular momentum transport, there remains a significant gap between the output of magneto-rotational instability (MRI) simulations and the synthesis of lessons learned into improved practical models. If discs are turbulent, then axisymmetric models must be recognized to be sensible only as mean field theories. Such is the case for the wonderfully practical and widely used framework of Shakura-Sunyaev (SS73). This model is most justifiable when the radial angular momentum transport dominates in discs and the transport is assumed to take the form of a local viscosity. However, the importance of large scale fields in coronae and jets and numerical evidence from MRI simulations points to a significant fraction of transport bein...

  6. Density waves in the shearing sheet III. Disc heating

    E-Print Network [OSTI]

    B. Fuchs

    2001-04-25T23:59:59.000Z

    The problem of dynamical heating of galactic discs by spiral density waves is discussed using the shearing sheet model. The secular evolution of the disc is described quantitatively by a diffusion equation for the distribution function of stars in the space spanned by integrals of motion of the stars, in particular the radial action integral and an integral related to the angular momentum. Specifically, disc heating by a succession of transient, `swing amplified' density waves is studied. It is shown that such density waves lead predominantly to diffusion of stars in radial action space. The stochastical changes of angular momenta of the stars and the corresponding stochastic changes of the guiding centre radii of the stellar orbits induced by this process are much smaller.

  7. Solution of the H3+ model on a disc

    E-Print Network [OSTI]

    Kazuo Hosomichi; Sylvain Ribault

    2007-01-17T23:59:59.000Z

    We determine all the correlators of the H3+ model on a disc with AdS2-brane boundary conditions in terms of correlators of Liouville theory on a disc with FZZT-brane boundary conditions. We argue that the Cardy-Lewellen constraints are weaker in the H3+ model than in rational conformal field theories due to extra singularities of the correlators, but strong enough to uniquely determine the bulk two-point function on a disc. We confirm our results by detailed analyses of the bulk-boundary two-point function and of the boundary two-point function. In particular we find that, although the target space symmetry preserved by AdS2-branes is the group SL(2,R), the open string states between two distinct parallel AdS2-branes belong to representations of the universal covering group.

  8. Dust trapping by spiral arms in gravitationally unstable protostellar discs

    E-Print Network [OSTI]

    Dipierro, Giovanni; Lodato, Giuseppe; Testi, Leonardo

    2015-01-01T23:59:59.000Z

    In this paper we discuss the influence of gravitational instabilities in massive protostellar discs on the dynamics of dust grains. Starting from a Smoothed Particle Hydrodynamics (SPH) simulation, we have computed the evolution of the dust in a quasi-static gas density structure typical of self-gravitating disc. For different grain size distributions we have investigated the capability of spiral arms to trap particles. We have run 3D radiative transfer simulations in order to construct maps of the expected emission at (sub-)millimetre and near-infrared wavelengths. Finally, we have simulated realistic observations of our disc models at (sub-)millimetre and near-infrared wavelengths as they may appear with the Atacama Large Millimetre/sub-millimetre Array (ALMA) and the High-Contrast Coronographic Imager for Adaptive Optics (HiCIAO) in order to investigate whether there are observational signatures of the spiral structure. We find that the pressure inhomogeites induced by gravitational instabilities produce a...

  9. Abundances of metal-weak thick-disc candidates

    E-Print Network [OSTI]

    P. Bonifacio; M. Centurion; P. Molaro

    1999-06-03T23:59:59.000Z

    High resolution spectra of 5 candidate metal-weak thick-disc stars suggested by Beers & Sommer-Larsen (1995) are analyzed to determine their chemical abundances. The low abundance of all the objects has been confirmed with metallicity reaching [Fe/H]=-2.9. However, for three objects, the astrometric data from the Hipparcos catalogue suggests they are true halo members. The remaining two, for which proper-motion data are not available, may have disc-like kinematics. It is therefore clear that it is useful to address properties of putative metal-weak thick-disc stars only if they possess full kinematic data. For CS 22894-19 the abundance pattern similar to those of typical halo stars is found, suggesting that chemical composition is not a useful discriminant between thick-disc and halo stars. CS 29529-12 is found to be C enhanced with [C/Fe]=+1.0; other chemical peculiarities involve the s process elements: [Sr/Fe]=-0.65 and [Ba/Fe]=+0.62, leading to a high [Ba/Sr] considerably larger than what is found in more metal-rich carbon-rich stars, but similar to LP 706-7 and LP 625-44 discussed by Norris et al (1997a). Hipparcos data have been used to calculate the space velocities of 25 candidate metal-weak thick-disc stars, thus allowing us to identify 3 bona fide members, which support the existence of a metal-poor tail of the thick-disc, at variance with a claim to the contrary by Ryan & Lambert (1995).

  10. Is the Dark Disc contribution to Dark Matter Signals important ?

    E-Print Network [OSTI]

    Fu-Sin Ling

    2010-07-11T23:59:59.000Z

    Recent N-body simulations indicate that a thick disc of dark matter, co-rotating with the stellar disc, forms in a galactic halo after a merger at a redshift $zdisc component in the Milky Way could affect dramatically dark matter signals in direct and indirect detection. In this letter, we discuss the possible signal enhancement in connection with the characteristics of the local velocity distributions. We argue that the enhancement is rather mild, but some subtle effects may arise. In particular, the annual modulation observed by DAMA becomes less constrained by other direct detection experiments.

  11. Probing self-gravitating protostellar discs using smoothed particle hydrodynamics and radiative transfer 

    E-Print Network [OSTI]

    Forgan, Duncan Hugh

    2011-01-01T23:59:59.000Z

    Stars are likely to form with non-zero initial angular momentum, and will consequently possess a substantial gaseous protostellar disc in the early phases of their evolution. At this early stage, the disc mass is expected ...

  12. The effect of cooling on the global stability of self-gravitating protoplanetary discs

    E-Print Network [OSTI]

    W. K. M. Rice; P. J. Armitage; M. R. Bate; I. A. Bonnell

    2002-11-05T23:59:59.000Z

    Using a local model Gammie (2001) has shown that accretion discs with cooling times t_cool 3/Omega evolve into a quasi-steady state. We use three-dimensional smoothed particle hydrodynamic simulations of protoplanetary accretion discs to test if the local results hold globally. We find that for disc masses appropriate for T Tauri discs, the fragmentation boundary still occurs at a cooling time close to t_cool = 3/Omega. For more massive discs, which are likely to be present at an earlier stage of the star formation process, fragmentation occurs for longer cooling times, but still within a factor of two of that predicted using a local model. These results have implications not only for planet formation in protoplanetary discs and star formation in AGN discs, but also for the redistribution of angular momentum which could be driven by the presence of relatively massive objects within the accretion disc.

  13. Videos | Photosynthetic Antenna Research Center

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize AvailableMedia Room /Video Video

  14. A correspondence between H3+ WZW and Liouville theories on discs

    E-Print Network [OSTI]

    Kazuo Hosomichi

    2007-01-29T23:59:59.000Z

    We discuss how the disc correlators of H3+ WZW model are determined in terms of those of Liouville theory.

  15. The Formation and Survival of Discs in a Lambda-CDM Universe

    E-Print Network [OSTI]

    Cecilia Scannapieco; Simon D. M. White; Volker Springel; Patricia B. Tissera

    2009-04-03T23:59:59.000Z

    We study the formation of galaxies in a Lambda-CDM Universe using high resolution hydrodynamical simulations with a multiphase treatment of gas, cooling and feedback, focusing on the formation of discs. Our simulations follow eight haloes similar in mass to the Milky Way and extracted from a large cosmological simulation without restriction on spin parameter or merger history. This allows us to investigate how the final properties of the simulated galaxies correlate with the formation histories of their haloes. We find that, at z = 0, none of our galaxies contain a disc with more than 20 per cent of its total stellar mass. Four of the eight galaxies nevertheless have well-formed disc components, three have dominant spheroids and very small discs, and one is a spheroidal galaxy with no disc at all. The z = 0 spheroids are made of old stars, while discs are younger and formed from the inside-out. Neither the existence of a disc at z = 0 nor the final disc-to-total mass ratio seems to depend on the spin parameter of the halo. Discs are formed in haloes with spin parameters as low as 0.01 and as high as 0.05; galaxies with little or no disc component span the same range in spin parameter. Except for one of the simulated galaxies, all have significant discs at z > ~2, regardless of their z = 0 morphologies. Major mergers and instabilities which arise when accreting cold gas is misaligned with the stellar disc trigger a transfer of mass from the discs to the spheroids. In some cases, discs are destroyed, while in others, they survive or reform. This suggests that the survival probability of discs depends on the particular formation history of each galaxy. A realistic Lambda-CDM model will clearly require weaker star formation at high redshift and later disc assembly than occurs in our models.

  16. UBC Video Collection / Raymond J. Hall (collector)

    E-Print Network [OSTI]

    Handy, Todd C.

    UBC Video Collection / Raymond J. Hall (collector) Compiled by Christopher Hives (2011) University / Physical Description Collector's Biographical Sketch Custodial History Scope and Content Item List (collector). - 1992-2002. 30 video recordings. Collector's Biographical Sketch Raymond Hall came to Vancouver

  17. Vehicle Technologies Office: Lightweighting Video Text Version

    Broader source: Energy.gov [DOE]

    This is a text version of the Motorweek video segment Materials Technology / Vehicle Lightweighting, which aired on April 21, 2014. The full video is on the Lightweight Materials for Cars and...

  18. Grounding spatial prepositions for video search

    E-Print Network [OSTI]

    Tellex, Stefanie A.

    Spatial language video retrieval is an important real-world problem that forms a test bed for evaluating semantic structures for natural language descriptions of motion on naturalistic data. Video search by natural language ...

  19. Arm-Hand-Finger Video Game Interaction

    E-Print Network [OSTI]

    Logsdon, Drew Anthony

    2012-02-14T23:59:59.000Z

    Despite the growing popularity and expansion of video game interaction techniques and research in the area of hand gesture recognition, the application of hand gesture video game interaction using arm, hand, and finger motion has not been...

  20. Comparison of alternative methods for deriving hydraulic properties and scaling factors from single-disc tension

    E-Print Network [OSTI]

    Mohanty, Binayak P.

    Comparison of alternative methods for deriving hydraulic properties and scaling factors from single-disc] Analysis of single-disc tension infiltrometer data is commonly based on the interpretation of the steady and the time needed to wet the contact sand under the disc was successfully filtered from the raw data using

  1. A laboratory plasma experiment for studying magnetic dynamics of accretion discs and jets

    E-Print Network [OSTI]

    Hsu, Scott

    A laboratory plasma experiment for studying magnetic dynamics of accretion discs and jets S. C. Hsu into the magnetic dynamics of accretion discs and jets. A high-speed multiple-frame CCD camera reveals images of the formation and helical instability of a collimated plasma, similar to MHD models of disc jets, and also

  2. Layered Wyner-Ziv video coding for noisy channels

    E-Print Network [OSTI]

    Xu, Qian

    2005-11-01T23:59:59.000Z

    The growing popularity of video sensor networks and video celluar phones has generated the need for low-complexity and power-e?cient multimedia systems that can handle multiple video input and output streams. While standard video coding...

  3. Techniques for CG Music Video Production: the making of

    E-Print Network [OSTI]

    Cinematography 4 2.1 Video Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2

  4. Video Personalization and Caching for Resource Constrained Environments

    E-Print Network [OSTI]

    Bhandarkar, Suchendra "Suchi" M.

    Video Personalization and Caching for Resource Constrained Environments Siddhartha Chattopadhyay Dept. of Computer Science, The University of Georgia, Athens, Georgia 30602-7404, USA Abstract: Video constrained, various video personalization strategies are used to provide personalized video content

  5. Resource Allocation in a Client/Server System for Massive Multi-Player Online Games

    E-Print Network [OSTI]

    Maciejewski, Anthony A.

    Resource Allocation in a Client/Server System for Massive Multi-Player Online Games Luis Diego-Player On-line Game (MMOG) has significant costs, such as maintenance of server rooms, server administration, and customer service. The capacity of servers in a client/server MMOG is hard to scale and cannot adjust

  6. To Upload Lesson Videos to the VAT Site: Getting to the Video Analysis of Teaching Homepage

    E-Print Network [OSTI]

    Qiu, Weigang

    1 To Upload Lesson Videos to the VAT Site: Getting to the Video Analysis of Teaching Students." In the navigation panel on the left, click on "Video Analysis of Teaching". The screen to the right is the VAT homepage. In order to upload or view the lesson video that you have

  7. How to batch upload video files with Unison How to batch upload video files with Unison

    E-Print Network [OSTI]

    Benos, Panayiotis "Takis"

    How to batch upload video files with Unison How to batch upload video files with Unison There are two different ways to upload already existing video files into Unison: Upload from the New Session page (only allows one video file to be uploaded at a time) Launching the editor in Composer (allows

  8. Chapter 55: Video-as-Data and Digital Video Manipulation Techniques for Transforming

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Chapter 55: Video-as-Data and Digital Video Manipulation Techniques for Transforming Learning and current progress of the Digital Interactive Video Exploration and Reflection (DIVER) Project at Stanford University. The DIVER Project aspires to accelerate cul- tural appropriation of video as a fluid expressive

  9. VIDEO IDENTIFICATION USING VIDEO TOMOGRAPHY Gustavo Leon, Hari Kalva, and Borko Furht

    E-Print Network [OSTI]

    Kalva, Hari

    VIDEO IDENTIFICATION USING VIDEO TOMOGRAPHY Gustavo Leon, Hari Kalva, and Borko Furht Department of Computer Science and Engineering, Florida Atlantic University, Boca Raton, FL, USA ABSTRACT Video popularity of online video services. The problem addressed in this paper is the identification of a given

  10. FILM AND VIDEO COLLECTION SCHEDULING REQUEST Date: Send To: Video Scheduling

    E-Print Network [OSTI]

    Cakoni, Fioralba

    FILM AND VIDEO COLLECTION SCHEDULING REQUEST Date: Requestor: Send To: Video Scheduling Film and Video Collection Department University of Delaware Library (302) 831-8419 FAX (302) 831-6197 Media within seven days, please check out media at the Film and Video Collection Department Service Desk

  11. Audio, Video and Audio-Visual Signatures for Short Video Clip Detection: Experiments on Trecvid2003

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Audio, Video and Audio-Visual Signatures for Short Video Clip Detection: Experiments on Trecvid2003.Senechal,Denis.Pellerin}@lis.inpg.fr, Laurent.Besacier@imag.fr ABSTRACT In this paper, we present the association of audio and video signatures for short video clip detection. First, we present an audio signature based on the spectral flatness measure

  12. Exploring Video Streaming in Public Settings: Shared Geocaching Over Distance Using Mobile Video Chat

    E-Print Network [OSTI]

    Cortes, Corinna

    Exploring Video Streaming in Public Settings: Shared Geocaching Over Distance Using Mobile Video Mountain View, CA, USA tkjudge@google.com ABSTRACT Our research explores the use of mobile video chat are doing the same activity together at the same time. We prototyped a wearable video chat experience

  13. High performance digital video servers: storage and retrieval of compressed scalable video

    E-Print Network [OSTI]

    Chang, Shih-Fu

    High performance digital video servers: storage and retrieval of compressed scalable video Seungyup compressiontechnologyhave ledto the emergence ofunprecedented forms of video communications. In the future, it is envisioned that users will be able to connect to a massive number of distributed video servers, from which users

  14. Getting Started with your LifeSize Video System Placing a Video Call

    E-Print Network [OSTI]

    Getting Started with your LifeSize Video System Placing a Video Call Dialing from the Redial list Dialing manually: Select the Video Call button. Press Enter the phone number or IP address. Press Ending a Video Call Press Select the call to terminate. Press Adjusting Sound: Press the button

  15. Viral Video Style: A Closer Look at Viral Videos on YouTube

    E-Print Network [OSTI]

    Shamos, Michael I.

    Viral Video Style: A Closer Look at Viral Videos on YouTube Lu Jiang, Yajie Miao, Yi Yang Introduction CMU Viral Video Dataset Statistical Characteristics Peak Day Prediction Conclusions #12;Outline Introduction CMU Viral Video Dataset Statistical Characteristics Peak Day Prediction

  16. Feedback in simulations of disc-galaxy major mergers

    E-Print Network [OSTI]

    T. J. Cox; Patrik Jonsson; Joel R. Primack; Rachel S. Somerville

    2007-09-25T23:59:59.000Z

    Using hydrodynamic simulations of disc-galaxy major mergers, we investigate the star formation history and remnant properties when various parametrizations of a simple stellar feedback model are implemented. The simulations include radiative cooling, a density-dependent star formation recipe and a model for feedback from massive stars. The feedback model stores supernova feedback energy within individual gas particles and dissipates this energy on a time-scale specified by two free parameters; tau_fb, which sets the dissipative time-scale, and n, which sets the effective equation of state in star-forming regions. Using a self-consistent disc galaxy, modelled after a local Sbc spiral, in both isolated and major-merger simulations, we investigate parametrizations of the feedback model that are selected with respect to the quiescent disc stability. These models produce a range of star formation histories that are consistent with the star formation relation found by Kennicutt. All major mergers produce a population of new stars that is highly centrally concentrated, demonstrating a distinct break in the r1/4 surface density profile, consistent with previous findings. The half-mass radius and one-dimensional velocity dispersion are affected by the feedback model used. Finally, we compare our results to those of previous simulations of star formation in disc-galaxy major mergers, addressing the effects of star formation normalization, the version of smoothed particle hydrodynamics (SPH) employed and assumptions about the interstellar medium.

  17. NIHAO III: The constant disc gas mass conspiracy

    E-Print Network [OSTI]

    Stinson, G S; Wang, L; Macciň, A V; Herpich, J; Bradford, J D; Quinn, T R; Wadsley, J; Keller, B

    2015-01-01T23:59:59.000Z

    We show that the cool gas masses of galactic discs reach a steady state that lasts many Gyr after their last major merger in cosmological hydrodynamic simulations. The mass of disc gas, M$_{\\rm gas}$, depends upon a galaxy halo's spin and virial mass, but not upon stellar feedback. Halos with low spin have high star formation efficiency and lower disc gas mass. Similarly, lower stellar feedback leads to more star formation so the gas mass ends up nearly the same irregardless of stellar feedback strength. Even considering spin, the M$_{\\rm gas}$ relation with halo mass, M$_{200}$ only shows a factor of 3 scatter. The M$_{\\rm gas}$--M$_{200}$ relation show a break at M$_{200}$=$2\\times10^{11}$ M$_\\odot$ that corresponds to an observed break in the M$_{\\rm gas}$--M$_\\star$ relation. The constant disc mass stems from a shared halo gas density profile in all the simulated galaxies. In their outer regions, the profiles are isothermal. Where the profile rises above $n=10^{-3}$ cm$^{-3}$, the gas readily cools and th...

  18. A fast algorithm for random sequential adsorption of discs

    E-Print Network [OSTI]

    Jian-Sheng WANG

    1994-02-17T23:59:59.000Z

    An efficient algorithm for random sequential adsorption of hard discs in two dimensions is implemented. A precise value for the coverage is obtained: theta(infty) = 0.547069. The asymptotic law theta(t) = theta(infty) - ct^{-1/2} is verified to a high accuracy. Pair correlation function is analyzed.

  19. Solution of the Percus-Yevick equation for hard discs

    E-Print Network [OSTI]

    M. Adda-Bedia; E. Katzav; D. Vella

    2008-01-31T23:59:59.000Z

    We solve the Percus-Yevick equation in two dimensions by reducing it to a set of simple integral equations. We numerically obtain both the pair correlation function and the equation of state for a hard disc fluid and find good agreement with available Monte-Carlo calculations. The present method of resolution may be generalized to any even dimension.

  20. Semantically Enabled Exploratory Video Search Jrg Waitelonis

    E-Print Network [OSTI]

    Weske, Mathias

    . The user enters a query string that might consist out of one or several keywords and Google's web searchSemantically Enabled Exploratory Video Search Jörg Waitelonis joerg comes the challenge of efficient methods in video content management, content-based video search

  1. Supplementary Material: Images, Papers and Videos (Electronic)

    E-Print Network [OSTI]

    Collomosse, John

    .tif Chinese dragon after 70 iterations of GA relaxation modelface.tif Man on a rock (detail on face before sharpening) relaxation.mpg Video of the GA relaxation process for dragon rock.tif Man on a rock] are included in the /papers directory. C.3 Videos The following source videos and animations are included

  2. Digital video camera workshop Sony VX2000

    E-Print Network [OSTI]

    Digital video camera workshop Sony VX2000 Sony DSR-PDX10 #12;Borrowing Eligibility · Currently are excellent for all types of video work · Both use MiniDV format (60min SP/90min LP) #12;Camcorder Kits ­ Firewire #12;Video Camera Operation Installing the Battery Sony VX2000 Insert the battery with the arrow

  3. Video Production Services Computing and IT

    E-Print Network [OSTI]

    Bolding, M. Chad

    #12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;Video Production Services Computing Captioning software #12;#12;Laptop/ speed typing software Encoder/ Decoder Video feed Captioning software Screen display #12;#12;Laptop/ speed typing software Encoder/ Decoder Video feed Captioning software

  4. Automatic Video Shot Detection from MPEG Stream

    E-Print Network [OSTI]

    Fan, Jianping

    Automatic Video Shot Detection from MPEG Stream Jianping Fan Department of Computer Science;Why we need video shots? a. Text Retrieval: Keyword Extraction Indexing Document Storage Reverse File Indexing #12;Why we need video shots? b. Database Query: Entity Extraction sid name login age gpa 53666

  5. Structured Video: A Data Type with ContentBased Access

    E-Print Network [OSTI]

    Gifford, David K.

    Structured Video: A Data Type with Content­Based Access Andrzej Duda y Ron Weiss September 1993 MIT: video indexing and searching, video databases, content­ based retrieval, video algebra #12; Abstract We describe structured video, a general video data model allowing free form annotation, composition

  6. Jupiter and Super-Earth embedded in a gaseous disc

    E-Print Network [OSTI]

    E. Podlewska; E. Szuszkiewicz

    2007-12-19T23:59:59.000Z

    In this paper we investigate the evolution of a pair of interacting planets - a Jupiter mass planet and a Super-Earth with the 5.5 Earth masses - orbiting a Solar type star and embedded in a gaseous protoplanetary disc. We focus on the effects of type I and II orbital migrations, caused by the planet-disc interaction, leading to the Super-Earth capture in first order mean motion resonances by the Jupiter. The stability of the resulting resonant system in which the Super-Earth is on the internal orbit relatively to the Jupiter has been studied numerically by means of full 2D hydrodynamical simulations. Our main motivation is to determine the Super-Earth behaviour in the presence of the gas giant in the system. It has been found that the Jupiter captures the Super-Earth into the interior 3:2 or 4:3 mean motion resonances and the stability of such configurations depends on the initial planet positions and eccentricity evolution. If the initial separation of planet orbits is larger or close to that required for the exact resonance than the final outcome is the migration of the pair of planets with the rate similar to that of the gas giant at least for time of our simulations. Otherwise we observe a scattering of the Super-Earth from the disc. The evolution of planets immersed in the gaseous disc has been compared with their behaviour in the case of the classical three-body problem when the disc is absent.

  7. Surface density profiles of collisionless disc merger remnants

    E-Print Network [OSTI]

    Thorsten Naab; Ignacio Trujillo

    2006-03-01T23:59:59.000Z

    We present a detailed surface density analysis of a large sample of simulated collisionless mergers of disc galaxies with bulges (mass ratios 1:1, 2:1, 3:1, 4:1, and 6:1) and without bulges (mass ratios 1:1 and 3:1). They were classified, according to their bulge--to--total ($B/T$) ratio, either as a one-component system or as a two-component systems. In general projection effects change the classification of a remnant. Only merger remnants of discs with bulges show properties similar to observed early--type galaxies. Their B/T ratios are in the range $0.2discs for 6:1 remnants. We found distinct correlations between the fitting parameters which are very similar to observed relations (e.g. larger bulges have lower effective surface densities). No indications for a correlation between the surface density profiles and other global parameters are found. The remnants have properties similar to giant elliptical galaxies in the intermediate mass regime. A binary disc merger origin for all early-type galaxies, especially the most massive ones, is unlikely. Observed nearby merger remnants have properties similar to the simulated remnants. They can have formed from binary disc mergers and might evolve into early--type galaxies within a few Gyrs (abbreviated).

  8. Migration of massive black hole binaries in self--gravitating accretion discs: Retrograde versus prograde

    E-Print Network [OSTI]

    Constanze Roedig; Alberto Sesana

    2013-07-24T23:59:59.000Z

    We study the interplay between mass transfer, accretion and gravitational torques onto a black hole binary migrating in a self-gravitating, retrograde circumbinary disc. A direct comparison with an identical prograde disc shows that: (i) because of the absence of resonances, the cavity size is a factor a(1+e) smaller for retrograde discs; (ii) nonetheless the shrinkage of a circular binary semi--major axis, a, is identical in both cases; (iii) a circular binary in a retrograde disc remains circular while eccentric binaries grow more eccentric. For non-circular binaries, we measure the orbital decay rates and the eccentricity growth rates to be exponential as long as the binary orbits in the plane of its disc. Additionally, for these co-planar systems, we find that interaction (~ non--zero torque) stems only from the cavity edge plus a(1+e) in the disc, i.e. for dynamical purposes, the disc can be treated as a annulus of small radial extent. We find that simple 'dust' models in which the binary- disc interaction is purely gravitational can account for all main numerical results, both for prograde and retrograde discs. Furthermore, we discuss the possibility of an instability occurring for highly eccentric binaries causing it to leave the disc plane, secularly tilt and converge to a prograde system. Our results suggest that there are two stable configurations for binaries in self-gravitating discs: the special circular retrograde case and an eccentric (e~ 0.6) prograde configuration as a stable attractor.

  9. Time-dependent models of two-phase accretion discs around black holes

    E-Print Network [OSTI]

    M. Mayer; J. E. Pringle

    2006-12-28T23:59:59.000Z

    We present time-dependent simulations of a two-phase accretion flow around a black hole. The accretion flow initially is composed of an optically thick and cool disc close to the midplane, while on top and below the disc there is a hot and optically thin corona. We consider several interaction mechanisms as heating of the disc by the corona and Compton cooling of the corona by the soft photons of the disc. Mass and energy can be exchanged between the disc and the corona due to thermal conduction. For the course of this more exploratory work, we limit ourselves to one particular model for a stellar mass black hole accreting at a low accretion rate. We confirm earlier both theoretical and observational results which show that at low accretion rates the disc close to the black hole cannot survive and is evaporated. Given the framework of this model, we now can follow through this phase of disc evaporation time dependently.

  10. Chemo-spectrophotometric evolution of spiral galaxies: III. Abundance and colour gradients in discs

    E-Print Network [OSTI]

    N. Prantzos; S. Boissier

    1999-11-07T23:59:59.000Z

    We study the relations between luminosity and chemical abundance profiles of spiral galaxies, using detailed models for the chemical and spectro-photometric evolution of galactic discs. The models are ``calibrated'' on the Milky Way disc and are successfully extended to other discs with the help of simple ``scaling'' relations, obtained in the framework of semi-analytic models of galaxy formation. We find that our models exhibit oxygen abundance gradients that increase in absolute value with decreasing disc luminosity (when expressed in dex/kpc) and are independent of disc luminosity (when expressed in dex/scalelength), both in agreement with observations. We notice an important strong correlation between abundance gradient and disc scalelength. These results support the idea of ``homologuous evolution'' of galactic discs.

  11. T-577: Security Advisory for Adobe Flash Player, Adobe Reader and Acrobat

    Broader source: Energy.gov [DOE]

    A critical vulnerability exists in Adobe Flash Player 10.2.152.33 and earlier versions (Adobe Flash Player 10.2.154.13 and earlier for Chrome users) for Windows, Macintosh, Linux and Solaris operating systems, Adobe Flash Player 10.1.106.16 and earlier versions for Android, and the Authplay.dll component that ships with Adobe Reader and Acrobat X (10.0.1) and earlier 10.x and 9.x versions of Reader and Acrobat for Windows and Macintosh operating systems.

  12. On the black hole limit of rotating discs and rings

    E-Print Network [OSTI]

    Andreas Kleinwächter; Hendrick Labranche; Reinhard Meinel

    2010-07-20T23:59:59.000Z

    Solutions to Einstein's field equations describing rotating fluid bodies in equilibrium permit parametric (i.e. quasi-stationary) transitions to the extreme Kerr solution (outside the horizon). This has been shown analytically for discs of dust and numerically for ring solutions with various equations of state. From the exterior point of view, this transition can be interpreted as a (quasi) black hole limit. All gravitational multipole moments assume precisely the values of an extremal Kerr black hole in the limit. In the present paper, the way in which the black hole limit is approached is investigated in more detail by means of a parametric Taylor series expansion of the exact solution describing a rigidly rotating disc of dust. Combined with numerical calculations for ring solutions our results indicate an interesting universal behaviour of the multipole moments near the black hole limit.

  13. Disc amplitudes, picture changing and space-time actions

    E-Print Network [OSTI]

    Katrin Becker; Guangyu Guo; Daniel Robbins

    2011-06-16T23:59:59.000Z

    We study in detail the procedure for obtaining couplings of D-branes to closed string fields by evaluating string theory disc amplitudes. We perform a careful construction of the relevant vertex operators and discuss the effects of inserting the boundary state which encodes the presence of the D-brane. We confront the issue of non-decoupling of BRST-exact states and prove that the problem is evaded for the computations we need, thus demonstrating that our amplitudes are automatically gauge-invariant and independent of the distribution of picture charge. Finally, we compute explicitly the two-point amplitudes of two NS-NS fields or one NS-NS and one R-R field on the disc, and we carefully compare all the lowest order terms with predictions from supergravity.

  14. Characterising the Gravitational Instability in Cooling Accretion Discs

    E-Print Network [OSTI]

    Peter Cossins; Giuseppe Lodato; Cathie Clarke

    2008-11-21T23:59:59.000Z

    We perform numerical analyses of the structure induced by gravitational instabilities in cooling gaseous accretion discs. For low enough cooling rates a quasi-steady configuration is reached, with the instability saturating at a finite amplitude in a marginally stable disc. We find that the saturation amplitude scales with the inverse square root of the cooling parameter beta = t_cool / t_dyn, which indicates that the heating rate induced by the instability is proportional to the energy density of the induced density waves. We find that at saturation the energy dissipated per dynamical time by weak shocks due is of the order of 20 per cent of the wave energy. From Fourier analysis of the disc structure we find that while the azimuthal wavenumber is roughly constant with radius, the mean radial wavenumber increases with radius, with the dominant mode corresponding to the locally most unstable wavelength. We demonstrate that the density waves excited in relatively low mass discs are always close to co-rotation, deviating from it by approximately 10 per cent. This can be understood in terms of the flow Doppler-shifted phase Mach number -- the pattern speed self-adjusts so that the flow into spiral arms is always sonic. This has profound effects on the degree to which transport through self-gravity can be modelled as a viscous process. Our results thus provide (a) a detailed description of how the self-regulation mechanism is established for low cooling rates, (b) a clarification of the conditions required for describing the transport induced by self-gravity through an effective viscosity, (c) an estimate of the maximum amplitude of the density perturbation before fragmentation occurs, and (d) a simple recipe to estimate the density perturbation in different thermal regimes.

  15. Mirror Symmetry, D-Branes and Counting Holomorphic Discs

    E-Print Network [OSTI]

    Mina Aganagic; Cumrun Vafa

    2000-12-05T23:59:59.000Z

    We consider a class of special Lagrangian subspaces of Calabi-Yau manifolds and identify their mirrors, using the recent derivation of mirror symmetry, as certain holomorphic varieties of the mirror geometry. This transforms the counting of holomorphic disc instantons ending on the Lagrangian submanifold to the classical Abel-Jacobi map on the mirror. We recover some results already anticipated as well as obtain some highly non-trivial new predictions.

  16. Radial mixing and the transition between the thick and thin Galactic discs

    E-Print Network [OSTI]

    Misha Haywood

    2008-05-13T23:59:59.000Z

    The analysis of the kinematics of solar neighbourhood stars shows that the low and high metallicity tails of the thin disc are populated by objects which orbital properties suggest an origin in the outer and inner galactic disc, respectively. Signatures of radial migration are identified in various recent samples, and are shown to be responsible for the high metallicity dispersion in the age-metallicity distribution. Most importantly, it is shown that the population of low metallicity wanderers of the thin disc (-0.7disc (which terminal metallicity is about -0.2 dex). It implies that the thin disc at the solar circle has started to form stars at about this same metallicity. This is also consistent with the fact that 'transition' objects, which have alpha-element abundance intermediate between that of the thick and thin discs, are found in the range [-0.4,-0.2] dex. Once the metal-poor thin disc stars are recognised for what they are - wanderers from the outer thin disc - the parenthood between the two discs can be identified on stars genuinely formed at the solar circle through an evolutionary sequence in [alpha/Fe] and [Fe/H] . Another consequence is that stars that can be considered as truly resulting of the chemical evolution at the solar circle have a metallicity restricted to about [-0.2,+0.2] dex, confirming an old idea that most chemical evolution in the Milky Way have preceded the thin disc formation.

  17. Warped discs and the directional stability of jets in Active Galactic Nuclei

    E-Print Network [OSTI]

    Priyamvada Natarajan; Philip J. Armitage

    1999-06-27T23:59:59.000Z

    Warped accretion discs in Active Galactic Nuclei (AGN) exert a torque on the black hole that tends to align the rotation axis with the angular momentum of the outer disc. We compute the magnitude of this torque by solving numerically for the steady state shape of the warped disc, and verify that the analytic solution of Scheuer and Feiler (1996) provides an excellent approximation. We generalise these results for discs with strong warps and arbitrary surface density profiles, and calculate the timescale on which the black hole becomes aligned with the angular momentum in the outer disc. For massive holes and accretion rates of the order of the Eddington limit the alignment timescale is always short (less than a Myr), so that jets accelerated from the inner disc region provide a prompt tracer of the angular momentum of gas at large radii in the disc. Longer timescales are predicted for low luminosity systems, depending on the degree of anisotropy in the disc's hydrodynamic response to shear and warp, and for the final decay of modest warps at large radii in the disc that are potentially observable via VLBI. We discuss the implications of this for the inferred accretion history of those Active Galactic Nuclei whose jet directions appear to be stable over long timescales. The large energy deposition rate at modest disc radii during rapid realignment episodes should make such objects transiently bright at optical and infrared wavelengths.

  18. Three dimensional SPH simulations of radiation-driven warped accretion discs

    E-Print Network [OSTI]

    Stephen B. Foulkes; Carole A. Haswell; James R. Murray

    2006-01-06T23:59:59.000Z

    We present three dimensional smoothed particle hydrodynamics (SPH) calculations of warped accretion discs in X-ray binary systems. Geometrically thin, optically thick accretion discs are illuminated by a central radiation source. This illumination exerts a non-axisymmetric radiation pressure on the surface of the disc resulting in a torque that acts on the disc to induce a twist or warp. Initially planar discs are unstable to warping driven by the radiation torque and in general the warps also precess in a retrograde direction relative to the orbital flow. We simulate a number of X-ray binary systems which have different mass ratios using a number of different luminosities for each. Radiation-driven warping occurs for all systems simulated. For mass ratios q ~ 0.1 a moderate warp occurs in the inner disc while the outer disc remains in the orbital plane (c.f. X 1916-053). For less extreme mass ratios the entire disc tilts out of the orbital plane (c.f. Her X-1). For discs that are tilted out of the orbital plane in which the outer edge material of the disc is precessing in a prograde direction we obtain both positive and negative superhumps simultaneously in the dissipation light curve (c.f. V603 Aql).

  19. Methanol Along the Path from Envelope to Protoplanetary Disc

    E-Print Network [OSTI]

    Drozdovskaya, Maria N; Visser, Ruud; Harsono, Daniel; van Dishoeck, Ewine F

    2014-01-01T23:59:59.000Z

    Interstellar methanol is considered to be a parent species of larger, more complex organic molecules. A physicochemical simulation of infalling parcels of matter is performed for a low-mass star-forming system to trace the chemical evolution from cloud to disc. An axisymmetric 2D semi-analytic model generates the time-dependent density and velocity distributions, and full continuum radiative transfer is performed to calculate the dust temperature and the UV radiation field at each position as a function of time. A comprehensive gas-grain chemical network is employed to compute the chemical abundances along infall trajectories. Two physical scenarios are studied, one in which the dominant disc growth mechanism is viscous spreading, and another in which continuous infall of matter prevails. The results show that the infall path influences the abundance of methanol entering each type of disc, ranging from complete loss of methanol to an enhancement by a factor of > 1 relative to the prestellar phase. Critical ch...

  20. Global m=1 modes and migration of protoplanetary cores in eccentric protoplanetary discs

    E-Print Network [OSTI]

    J. C. B. Papaloizou

    2002-04-11T23:59:59.000Z

    We calculate global $m=1$ modes with low pattern speed corresponding to introducing a finite eccentricity into a protoplanetary disc. We consider disc models which are either isolated or contain one or two protoplanets orbiting in an inner cavity. Global modes that are strongly coupled to inner protoplanets are found to have disc orbits which tend to have apsidal lines antialigned with respect to those of the inner protoplanets. Other modes corresponding to free disc modes may be global over a large range of length scales and accordingly be long lived. We consider the motion of a protoplanet in the earth mass range embedded in an eccentric disc and determine the equilibrium orbits which maintain fixed apsidal alignment with respect to the disc gas orbits. Equilibrium eccentricities are found to be comparable or possibly exceed the disc eccentricity. We then approximately calculate the tidal interaction with the disc in order to estimate the orbital migration rate. Results are found to deviate from the case of axisymmetric disc with near circular protoplanet orbit once eccentricities of protoplanet and disc orbits become comparable to the disc aspect ratio in magnitude. Aligned protoplanet orbits with very similar eccentricity to that of the gas disc are found to undergo litle eccentricity change while undergoing inward migration in general. However, for significantly larger orbital eccentricities, migration may be significantly reduced or even reverse from inwards to outwards. Thus the existence of global non circular motions in discs with radial excursions comparable to the semi-thickness may have important consequences for the migration and survival of protoplanetary cores in the earth mass range.

  1. Aussie LNG players target NE Asia in expansion bid

    SciTech Connect (OSTI)

    Not Available

    1994-02-28T23:59:59.000Z

    Australia's natural gas players, keen to increase their presence in world liquefied natural gas trade, see Asia as their major LNG market in the decades to come. That's despite the fact that two spot cargoes of Australian Northwest Shelf LNG were shipped to Europe during the last 12 months and more are likely in 1994. Opportunities for growth are foreseen within the confines of the existing Northwest Shelf gas project for the rest of the 1990s. But the main focus for potential new grassroots project developers and expansions of the existing LNG plant in Australia is the expected shortfall in contract volumes of LNG to Japan, South Korea, and Taiwan during 2000--2010. Traditionally the price of crude oil has been used as a basis for calculating LNG prices. This means the economics of any new 21st century supply arrangements are delicately poised because of the current low world oil prices, a trend the market believes is likely to continue. In a bid to lessen the effect of high initial capital outlays and still meet projected demand using LNG from new projects and expansion of the existing plant, Australia's gas producers are working toward greater cooperation with prospective Asian buyers.

  2. IM Sports BOCCE Rules TEAM: A normal team consists of 4 players, but may play with 3, 2 or 1 player as needed. No New Players may be used in

    E-Print Network [OSTI]

    Maroncelli, Mark

    IM Sports ­ BOCCE Rules TEAM: A normal team consists of 4 players, but may play with 3, 2 or 1 as many of your teams Bocce closer to the Jack than your opponent's closest Bocce. A team is (Diagram shows 2 points for Team A) awarded 1-point per Bocce that is closer than opponents to the Jack

  3. T-604: Google Chrome updated version of the Adobe Flash player...

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

    of the Adobe Flash player April 15, 2011 - 4:30am Addthis PROBLEM: Chrome Stable and Beta channels have been updated to 10.0.648.134 for Windows, Mac, Linux and Chrome Frame...

  4. Leontief Economies Encode Nonzero Sum Two-Player Games Bruno Codenotti

    E-Print Network [OSTI]

    Saberi, Amin

    Leontief Economies Encode Nonzero Sum Two-Player Games Bruno Codenotti Amin Saberi Kasturi@tti-c.org. Department of Management Science and Engineering, Stanford University, Stanford CA 94305. Email: saberi

  5. New players, opportunities and frustrations in the global marketplace -- Results of an industry-wide survey

    SciTech Connect (OSTI)

    Schwartz, R.

    1998-07-01T23:59:59.000Z

    Review of the annual industry-wide survey of the independent power industry, including top players, market shares, company growth rates, player activities by country and market expectations. The author offers fresh analysis on industry trends based on the survey, conducted through direct interviews with nearly 200 global power developers. Unlike other overviews offering demand projections of various power markets, this survey takes a look at the industry itself.

  6. DOE and Critical Materials Video (Text Version)

    Broader source: Energy.gov [DOE]

    This is a text version of the "DOE and Critical Materials" video presented at the Critical Materials Workshop, held on April 3, 2012 in Arlington, Virginia.

  7. Essential Principles of Energy Videos Teacher Guide

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

    Center for Science Education. Together with the Energy Literacy Framework, the videos provide a valuable set of resources for public understanding and for instruction....

  8. Videos | Y-12 National Security Complex

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize AvailableMedia Room /Video VideoVideos Videos

  9. Range Temporal Search on Sensor-rich Mobile Videos Preliminaries

    E-Print Network [OSTI]

    Shahabi, Cyrus

    Range Temporal Search on Sensor-rich Mobile Videos Preliminaries FOV model - A video as a set of video frames - Each video frame is modeled a Field Of View (FOV) based on the metadata (location, orientation, timestamp, etc.) of the video. - Note the size of is the maximum visible distance

  10. Video Source Identification in Lossy Wireless Networks Shaxun Chen

    E-Print Network [OSTI]

    California at Davis, University of

    Video Source Identification in Lossy Wireless Networks Shaxun Chen , Amit Pande , Kai Zeng@ucdavis.edu, kzeng@umich.edu, pmohapatra@ucdavis.edu Abstract-- Video source identification is very important in valida- ting video evidence, tracking down video piracy crimes and regu- lating individual video sources

  11. Temporal Segmentation of Egocentric Videos Yair Poleg Chetan Arora

    E-Print Network [OSTI]

    Peleg, Shmuel

    Temporal Segmentation of Egocentric Videos Yair Poleg Chetan Arora Shmuel Peleg The Hebrew life logging egocentric videos. Browsing such long unstruc- tured videos is time consuming and tedious videos, enabling ef- ficient browsing, indexing and summarization of the long videos. Two sources

  12. AUTOMATED EXTRACTION OF LECTURE OUTLINES FROM LECTURE VIDEOS

    E-Print Network [OSTI]

    Weske, Mathias

    AUTOMATED EXTRACTION OF LECTURE OUTLINES FROM LECTURE VIDEOS A Hybrid Solution for Lecture Video}@hpi.uni-potsdam.de Keywords: Recorded Lecture Videos, Tele-teaching, Video Indexing, Multimedia Retrieval. Abstract: Multimedia-based tele-teaching and lecture video portals have become more and more popular in the last few

  13. Sandia Energy - EC Video Library

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > TheNuclear Press ReleasesInApplied &ClimateContact UsECEC Video

  14. Sandia National Laboratories: News: Videos

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > TheNuclearHomeland and NuclearReport PartnershipsNews Videos San An

  15. Global MHD simulations of stratified and turbulent protoplanetary discs. I. Model properties

    E-Print Network [OSTI]

    Sebastien Fromang; Richard P. Nelson

    2006-06-29T23:59:59.000Z

    We present the results of global 3-D MHD simulations of stratified and turbulent protoplanetary disc models. The aim of this work is to develop thin disc models capable of sustaining turbulence for long run times, which can be used for on-going studies of planet formation in turbulent discs. The results are obtained using two codes written in spherical coordinates: GLOBAL and NIRVANA. Both are time--explicit and use finite differences along with the Constrained Transport algorithm to evolve the equations of MHD. In the presence of a weak toroidal magnetic field, a thin protoplanetary disc in hydrostatic equilibrium is destabilised by the magnetorotational instability (MRI). When the resolution is large enough (25 vertical grid cells per scale height), the entire disc settles into a turbulent quasi steady-state after about 300 orbits. Angular momentum is transported outward such that the standard alpha parameter is roughly 4-6*10^{-3}. We find that the initial toroidal flux is expelled from the disc midplane and that the disc behaves essentially as a quasi-zero net flux disc for the remainder of the simulation. As in previous studies, the disc develops a dual structure composed of an MRI--driven turbulent core around its midplane, and a magnetised corona stable to the MRI near its surface. By varying disc parameters and boundary conditions, we show that these basic properties of the models are robust. The high resolution disc models we present in this paper achieve a quasi--steady state and sustain turbulence for hundreds of orbits. As such, they are ideally suited to the study of outstanding problems in planet formation such as disc--planet interactions and dust dynamics.

  16. Videos

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize AvailableMedia Room /

  17. Videos

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch >Internship Program TheSite MapScienceVentilation News

  18. Video Primal Sketch: A Generic Middle-Level Representation of Video Institute for Information and System Sciences

    E-Print Network [OSTI]

    Zhu, Song Chun

    Video Primal Sketch: A Generic Middle-Level Representation of Video Zhi Han Zongben Xu Institute This paper presents a middle-level video representation named Video Primal Sketch (VPS), which integrates two. This paper makes three contributions: i) learning a dictionary of video primitives as parametric generative

  19. Dust filtration at gap edges: Implications for the spectral energy distributions of discs with embedded planets

    E-Print Network [OSTI]

    W. K. M. Rice; Philip J. Armitage; Kenneth Wood; Giuseppe Lodato

    2006-09-29T23:59:59.000Z

    The spectral energy distributions (SEDs) of some T Tauri stars display a deficit of near-IR flux that could be a consequence of an embedded Jupiter-mass planet partially clearing an inner hole in the circumstellar disc. Here, we use two-dimensional numerical simulations of the planet-disc interaction, in concert with simple models for the dust dynamics, to quantify how a planet influences the dust at different radii within the disc. We show that pressure gradients at the outer edge of the gap cleared by the planet act as a filter - letting particles smaller than a critical size through to the inner disc while holding back larger particles in the outer disc. The critical particle size depends upon the disc properties, but is typically of the order of 10 microns. This filtration process will lead to discontinuous grain populations across the planet's orbital radius, with small grains in the inner disc and an outer population of larger grains. We show that this type of dust population is qualitatively consistent with SED modelling of systems that have optically thin inner holes in their circumstellar discs. This process can also produce a very large gas-to-dust ratio in the inner disc, potentially explaining those systems with optically thin inner cavities that still have relatively high accretion rates.

  20. The spectra of accretion discs in low-mass X-ray binaries

    E-Print Network [OSTI]

    R. R. Ross; A. C. Fabian

    1995-11-14T23:59:59.000Z

    We present self-consistent models for the radiative transfer in Shakura-Sunyaev accretion discs in bright low-mass X-ray binaries (LMXB). Our calculations include the full effects of incoherent Compton scattering and the vertical temperature structure within the disc, as well as the effects of Doppler blurring and gravitational redshift. We find that the observed X-ray spectra are well fit by exponentially cutoff power-law models. The difference between the observed total spectrum and our calculated disc spectrum should reveal the spectrum of the disc/neutron star boundary layer and other emitting regions considered to be present in LMXB.

  1. Neutron scattering residual stress measurements on gray cast iron brake discs

    SciTech Connect (OSTI)

    Spooner, S.; Payzant, E.A.; Hubbard, C.R. [and others

    1996-11-01T23:59:59.000Z

    Neutron diffraction was used to investigate the effects of a heat treatment designed to remove internal residual stresses in brake discs. It is believed that residual stresses may change the rate of deformation of the discs during severe braking conditions when the disc temperature is increased significantly. Neutron diffraction was used to map out residual strain distributions in a production disc before and after a stress-relieving heat treatment. Results from these neutron diffraction experiments show that some residual strains were reduced by as much as 400 microstrain by stress relieving. 5 refs., 5 figs., 1 tab.

  2. Properties of vertically self-gravitating accretion discs with a dissipative corona

    E-Print Network [OSTI]

    Fazeleh Khajenabi; Peter Duffy

    2008-05-30T23:59:59.000Z

    The steady-state structure of a disc with a corona is analyzed when the vertical component of the gravitational force due to the self-gravity of the disc is considered. For the energy exchange between the disc and the corona, we assume a fraction f of the dissipated energy inside the accretion disc is transported to the corona via the magnetic tubes. Analytical solutions corresponding to a prescription for f (in which this parameter directly depends on the ratio of the gas pressure to the total pressure) or free f are presented and their physical properties are studied in detail. We show that the existence of the corona not only decreases the temperature of the disc, but also increases the surface density.The vertical component of the gravitational force due to the self-gravity of the disc decreases the self-gravitating radius and the mass of the fragments at this radius. However, as more energy is transported from the disc to the corona, the effect of the vertical component of the gravitational force due to the self-gravity of the disc on the self-gravitating radius becomes weaker, though the mass of the fragments is reduced irrespective of the amount of the energy exchange from the disc to the corona.

  3. Hydrodynamic Simulations of Propagating Warps and Bending Waves In Accretion Discs

    E-Print Network [OSTI]

    Richard P. Nelson; John C. B. Papaloizou

    1999-07-06T23:59:59.000Z

    We present the results of a study of propagating warp or bending waves in accretion discs. Three dimensional hydrodynamic simulations were performed using SPH, and the results of these are compared with calculations based on the linear theory of warped discs. We consider primarily the physical regime in which the dimensionless viscosity parameter `alpha' disc aspect ratio, so that bending waves are expected to propagate. We also present calculations in which `alpha' > H/r, where the warps are expected to behave diffusively. Small amplitude perturbations are studied in both Keplerian and slightly non Keplerian discs, and we find that the SPH results can be reasonably well fitted by those of the linear theory. The main results of these calculations are: (1) the warp in Keplerian discs when `alpha' H/r, (3) the non Keplerian discs exhibit a substantially more dispersive behaviour of the warps. Initially imposed higher amplitude nonlinear warping disturbances were studied in Keplerian discs. The results indicate that nonlinear warps can lead to the formation of shocks, and that the evolution of the warp becomes less wave-like and more diffusive in character. This work is relevant to the study of the warped accretion discs that may occur around Kerr black holes or in misaligned binary systems. The results indicate that SPH can accurately model the hydrodynamics of warped discs, even when using rather modest numbers of particles.

  4. Dependence of fragmentation in self-gravitating accretion discs on small scale structure

    E-Print Network [OSTI]

    Young, Matthew D

    2015-01-01T23:59:59.000Z

    We propose a framework for understanding the fragmentation criterion for self-gravitating discs which, in contrast to studies that emphasise the `gravoturbulent' nature of such discs, instead focuses on the properties of their quasi-regular spiral structures. Within this framework there are two evolutionary paths to fragmentation: i) collapse on the free-fall time, which requires that the ratio of cooling time to dynamical time ($\\beta$) $disc. We perform 2D grid simulations which demonstrate numerically converged fragmentation at $\\beta disc. Such simulations thus only allow fragmentation via route i) above...

  5. Eccentric discs in binaries with intermediate mass ratios: Superhumps in the VY Sculptoris stars

    E-Print Network [OSTI]

    J. R. Murray; B. Warner; D. T. Wickramasinghe

    2000-02-23T23:59:59.000Z

    We investigate the role of the eccentric disc resonance in systems with mass ratios q greater than 1/4, and demonstrate the effects that changes in the mass flux from the secondary star have upon the disc radius and structure. The addition of material with low specific angular momentum to its outer edge restricts a disc radially. Should the mass flux from the secondary be reduced, it is possible for the disc in a system with mass ratio as large as 1/3 to expand to the 3:1 eccentric inner Lindblad resonance and for superhumps to be excited.

  6. Strong effect of the cluster environment on the size of protoplanetary discs?

    E-Print Network [OSTI]

    Vincke, Kirsten; Pfalzer, Susanne

    2015-01-01T23:59:59.000Z

    Context. Most stars are born in clusters, thus the protoplanetary discs surrounding the newly formed stars might be influenced by this environment. Isolated star-disc encounters have previously been studied, and it was shown that very close encounters are necessary to completely destroy discs. However, relatively distant encounters are still able to change the disc size considerably. Aims. We quantify the importance of disc-size reduction that is due to stellar encounters in an entire stellar population. Methods. We modelled young, massive clusters of different densities using the code Nbody6 to determine the statistics of stellar encounter parameters. In a second step, we used these parameters to investigate the effect of the environments on the disc size. For this purpose, we performed a numerical experiment with an artificial initial disc size of 105 AU. Results. We quantify to which degree the disc size is more sensitive to the cluster environment than to the disc mass or frequency. We show that in all in...

  7. Learnersourcing Subgoal Labels for How-to Videos

    E-Print Network [OSTI]

    Weir, Sarah

    Websites like YouTube host millions of how-to videos, but the interfaces are not optimized for learning. Previous research suggests that users learn more from how-to videos when the information from the video is presented ...

  8. Analyzing video compression for transporting over wireless fading channels

    E-Print Network [OSTI]

    Kannan, Karthik

    2006-10-30T23:59:59.000Z

    Wireless video communication is becoming increasingly popular these days with new applications such as TV on mobile and video phones. Commercial success of these applications requires superior video quality at the receiver. So it is imperative...

  9. New videos debut in February | The Ames Laboratory

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

    New videos debut in February Two new videos debutted on the Ames Laboratory website (and YouTube channel). The first one is a new introductory video featuring Director Adam...

  10. RealityFlythrough : a system for ubiquitous video

    E-Print Network [OSTI]

    McCurdy, Neil James

    2007-01-01T23:59:59.000Z

    IEEE Trans. Circuits Syst. Video Techn. , 13(7):560–576,Chapter 3 An Abstraction for Ubiquitous Video . . . 3.1.repre- sentations of video sequences and their applications.

  11. Automatic 3D facial expression analysis in videos

    E-Print Network [OSTI]

    Chang, Y; Vieira, M; Turk, M; Velho, L

    2005-01-01T23:59:59.000Z

    with the background in videos [26] are important topics forSystem for Real-Time 3D Video. IEEE Int. Workshop onExpression Analysis in Videos Ya Chang 1 , Marcelo Vieira

  12. Real-time fire detection in low quality video

    E-Print Network [OSTI]

    True, Nicholas James

    2010-01-01T23:59:59.000Z

    Motivation for a Robust Video-based Fire Detection SystemFigure 3.1: Screen shots of training videos with fire inshots of training videos with no fire in them. . . . . . .

  13. Solid-State Lighting Videos | Department of Energy

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

    Information Resources Solid-State Lighting Videos Solid-State Lighting Videos On this page you can access DOE Solid-State Lighting (SSL) Program videos. photo of a university...

  14. How to Upload Videos to YouTube To submit a video to the event, you should make a 30-to-60-second video. You can use your cell

    E-Print Network [OSTI]

    Engel, Robert

    How to Upload Videos to YouTube To submit a video to the event, you should make a 30-to-60-second video. You can use your cell phone, a video camera, your webcam, or other sources for your video. You can use various video editing programs to make your video, including iMovie (on Macs), Windows Live

  15. Learning Contextual Variations for Video Segmentation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Learning Contextual Variations for Video Segmentation Vincent Martin and Monique Thonnat INRIA.R.Martin, Monique.Thonnat}@sophia.inria.fr, http://www-sop.inria.fr/pulsar/ Abstract. This paper deals with video-illumination changes and long term changes are present. In this situation, the major difficulty at the segmentation

  16. Video Matching Peter Sand and Seth Teller

    E-Print Network [OSTI]

    Ouhyoung, Ming

    Video Matching Peter Sand and Seth Teller MIT Computer Science and Artificial Intelligence robotic motion control systems that would normally be used to ensure registra- tion of multiple video due to moving people, changes in lighting, and/or different exposure settings. e-mail: {sand

  17. Video sculpture:spatio-temporal warping 

    E-Print Network [OSTI]

    Groves, Jeff David

    2004-09-30T23:59:59.000Z

    -dimensional video as a way to do non- photorealistic rendering(NPR). The big step forward is their implementation of what they refer to as rendering solids[17]. These objects perform some set of operations on the video cube for some number of frames and section...

  18. Internet video streaming using 3-D SPIHT

    E-Print Network [OSTI]

    Jiang, Jianhong

    2001-01-01T23:59:59.000Z

    Internet video streaming is a new way of distributing video over the Internet. It is an important component of Internet multimedia. Due to the increasing demand of multimedia on the World Wide Web, it has experienced explosive growth in the last...

  19. Adaptive best effort protocols for video delivery

    E-Print Network [OSTI]

    Madhwaraj, Ashwin Raj

    1998-01-01T23:59:59.000Z

    This thesis describes the design and implementation of ics. transport level protocols running on top of the IP layer to transmit video data over packet switched networks. These protocols address the issues of meeting real-time deadlines of the video...

  20. Quadrennial Technology Review Strategy Videos with Under Secretary...

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

    Quadrennial Technology Review Strategy Videos with Under Secretary for Science Steven Koonin Quadrennial Technology Review Strategy Videos with Under Secretary for Science Steven...

  1. NNSA Releases Pictures, Video of Consequence Management Response...

    Energy Savers [EERE]

    Releases Pictures, Video of Consequence Management Response Teams Deploying to Japan NNSA Releases Pictures, Video of Consequence Management Response Teams Deploying to Japan March...

  2. Essential Principles of Energy Videos Student Analysis Guide

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

    you are a video designer. Before playing one of the Essential Principles of Energy Videos, look at the text of the "Energy Literacy Essential Principle" and its Fundamental...

  3. Selection of Long-Term Reference Frames in Dual-Frame Video Coding Using Simulated Annealing

    E-Print Network [OSTI]

    Tiwari, M.; Cosman, P. C.

    2008-01-01T23:59:59.000Z

    Index Terms—Dual-frame video coding, long-term reference frame, simulated annealing, video compression.

  4. Dark Matter Disc Enhanced Neutrino Fluxes from the Sun and Earth

    E-Print Network [OSTI]

    Tobias Bruch; Annika H. G. Peter; Justin Read; Laura Baudis; George Lake

    2009-04-21T23:59:59.000Z

    As disc galaxies form in a hierarchical cosmology, massive merging satellites are preferentially dragged towards the disc plane. The material accreted from these satellites forms a dark matter disc that contributes 0.25 - 1.5 times the non-rotating halo density at the solar position. Here, we show the importance of the dark disc for indirect dark matter detection in neutrino telescopes. Previous predictions of the neutrino flux from WIMP annihilation in the Earth and the Sun have assumed that Galactic dark matter is spherically distributed with a Gaussian velocity distribution, the standard halo model. Although the dark disc has a local density comparable to the dark halo, its higher phase space density at low velocities greatly enhances capture rates in the Sun and Earth. For typical dark disc properties, the resulting muon flux from the Earth is increased by three orders of magnitude over the SHM, while for the Sun the increase is an order of magnitude. This significantly increases the sensitivity of neutrino telescopes to fix or constrain parameters in WIMP models. The flux from the Earth is extremely sensitive to the detailed properties of the dark disc, while the flux from the Sun is more robust. The enhancement of the muon flux from the dark disc puts the search for WIMP annihilation in the Earth on the same level as the Sun for WIMP masses < 100 GeV.

  5. Magnetized accretion-ejection structures IV. Magnetically-driven jets from resistive, viscous, Keplerian discs

    E-Print Network [OSTI]

    Fabien Casse; Jonathan Ferreira

    1999-11-25T23:59:59.000Z

    We present steady-state calculations of self-similar magnetized accretion discs driving cold, adiabatic, non-relativistic jets. For the first time, both the magnetic torque due to the jets and a turbulent "viscous" torque are taken into account. This latter torque allows a dissipation of the accretion power as radiation at the disc surfaces, while the former predominantly provides jets with power. The parameter space of these structures has been explored. It is characterized by four free parameters, namely the disc aspect ratio and three MHD turbulence parameters, related to the anomalous magnetic diffusivities and viscosity. It turns out that launching cold jets from thin, dissipative discs implies anisotropic turbulent dissipation. Jets that asymptotically reach a high Alfvenic Mach number are only produced by weakly dissipative discs. We obtained general analytical relations between disc and jet quantities that must be fulfilled by any steady-state model of cold jets, launched from a large radial extension of thin discs. We also show that such discs cannot have a dominant viscous torque. This is because of the chosen geometry, imposing the locus of the Alfven surface. Some observational consequences of these cold magnetized accretion-ejection structures are also briefly discussed.

  6. A SCUBA-2 850 micron Survey of Protoplanetary Discs in the IC 348 Cluster

    E-Print Network [OSTI]

    Cieza, L; Kourkchi, E; Andrews, S; Casassus, S; Graves, S; Schreiber, M

    2015-01-01T23:59:59.000Z

    We present 850 micron observations of the 2-3 Myr cluster IC 348 in the Perseus molecular cloud using the SCUBA-2 camera on the James Clerk Maxwell Telescope. Our SCUBA-2 map has a diameter of 30 arcmin and contains ~370 cluster members, including ~200 objects with IR excesses. We detect a total of 13 discs. Assuming standard dust properties and a gas to dust mass ratio of 100, we derive disc masses ranging from 1.5 to 16 M_JUP . We also detect 8 Class 0/I protostars. We find that the most massive discs (M_Disc > 3 MJUP ; 850 micron fux > 10 mJy) in IC 348 tend to be transition objects according to the characteristic "dip" in their infrared Spectral Energy Distributions (SEDs). This trend is also seen in other regions. We speculate that this could be an initial conditions effect (e.g., more massive discs tend to form giant planets that result in transition disc SEDs) and/or a disc evolution effect (the formation of one or more massive planets results in both a transition disc SED and a reduction of the accret...

  7. Quantum McKay correspondence for disc invariants of orbifold vertex

    E-Print Network [OSTI]

    Hua-Zhong Ke; Jian Zhou

    2014-10-16T23:59:59.000Z

    In this note, we describe a a systematic procedure to find toric crepant resolutions of orbifold vertex, and show that the generating series of certain disc invariants of the orbifold vertex can be suitably identified with the generating series of certain disc invariants of its toric crepant resolutions.

  8. Bit-Rate Allocation for Multiple Video Streams Using a Pricing-Based Mechanism

    E-Print Network [OSTI]

    Tiwari, M.; Groves, T.; Cosman, P.

    2011-01-01T23:59:59.000Z

    total available supply. (a) g8 video stream. (b) g9 video100 kb per slot per user. (a) g8 video stream. (b) g11 videoand demand normalization. (a) g8 video stream. (b) g9 video

  9. High accretion rates in magnetised Keplerian discs mediated by a Parker instability driven dynamo

    E-Print Network [OSTI]

    Johansen, Anders

    2008-01-01T23:59:59.000Z

    Hydromagnetic stresses in accretion discs have been the subject of intense theoretical research over the past one and a half decades. Most of the disc simulations have assumed a small initial magnetic field and studied the turbulence that arises from the magnetorotational instability. However, gaseous discs in galactic nuclei and in some binary systems are likely to have significant initial magnetisation. Motivated by this, we performed ideal magnetohydrodynamic simulations of strongly magnetised, vertically stratified discs in a Keplerian potential. Our initial equilibrium configuration, which has an azimuthal magnetic field in equipartion with thermal pressure, is unstable to the Parker instability. This leads to the expelling of magnetic field arcs, anchored in the midplane of the disc, to around five scale heights from the midplane. Transition to turbulence happens primarily through magnetorotational instability in the resulting vertical fields, although magnetorotational shear instability in the unpertur...

  10. On the fragility of nuclear stellar discs against galaxy mergers: surviving photometric and kinematic signatures of nuclear discs

    E-Print Network [OSTI]

    Sarzi, M; Dotti, M

    2015-01-01T23:59:59.000Z

    Nuclear stellar discs (NSDs) can help to constrain the assembly history of their host galaxies, as long as we can assume them to be fragile structures that are disrupted during merger events. In this work we investigate the fragility of NSDs by means of N-body simulations reproducing the last phases of a galaxy encounter, when the nuclear regions of the two galaxies merge. For this, we exposed a NSD set in the gravitational potential of the bulge and supermassive black hole of a primary galaxy to the impact of the supermassive black hole from a secondary galaxy. We explored merger events of different mass ratios, from major mergers with a 1:1 mass ratio to intermediate and minor interactions with 1:5 and 1:10 ratios, while considering various impact geometries. We analyse the end results of such mergers from different viewing angles and looked for possible photometric and kinematic signatures of the presence of a disc in the remnant surface density and velocity maps, while adopting detection limits from real ...

  11. Iron line profiles and self-shadowing from relativistic thick accretion discs

    E-Print Network [OSTI]

    Sheng-Miao Wu; Ting-Gui Wang

    2008-07-11T23:59:59.000Z

    We present Fe Kalpha line profiles from and images of relativistic discs with finite thickness around a rotating black hole using a novel code. The line is thought to be produced by iron fluorescence of a relatively cold X-ray illuminated material in the innermost parts of the accretion disc and provides an excellent diagnostic of accretion flows in the vicinity of black holes. Previous studies have concentrated on the case of a thin, Keplerian accretion disc. This disc must become thicker and sub-Keplerian with increasing accretion rates. These can affect the line profiles and in turn can influence the estimation of the accretion disc and black hole parameters from the observed line profiles. We here embark on, for the first time, a fully relativistic computation which offers key insights into the effects of geometrical thickness and the sub-Keplerian orbital velocity on the line profiles. We include all relativistic effects such as frame-dragging, Doppler boost, time dilation, gravitational redshift and light bending. We find that the separation and the relative height between the blue and red peaks of the line profile diminish as the thickness of the disc increases. This code is also well-suited to produce accretion disc images. We calculate the redshift and flux images of the accretion disc and find that the observed image of the disc strongly depends on the inclination angle. The self-shadowing effect appears remarkable for a high inclination angle, and leads to the black hole shadow being completely hidden by the disc itself.

  12. Acceptance test procedure for the overview video camera system (OVS)

    SciTech Connect (OSTI)

    Pardini, A.F.

    1995-10-01T23:59:59.000Z

    Acceptance Test Procedure for testing the Light Duty Utility Arm (LDUA) Overview Video Camera System (OVS).

  13. Visualizing YouTube Video Clusters Derek Thrasher

    E-Print Network [OSTI]

    Mountziaris, T. J.

    Visualizing YouTube Video Clusters Derek Thrasher University of Massachusetts Amherst REU Student Faculty Adviser: Lixin Gao Abstract In recent years, video streaming has become a significant part of our everyday lives. Advertisers, media companies, and video up-loaders are interested in what makes a video

  14. Structured Video: A Data Type with Content-Based Access

    E-Print Network [OSTI]

    Gifford, David K.

    Structured Video: A Data Type with Content-Based Access Andrzej Duday Ron Weiss September 1993 MIT or implied, of the Defense Advanced Research Projects Agency or the U.S. Government. #12;Keywords: video indexing and searching, video databases, content- based retrieval, video algebra #12;Abstract We describe

  15. Bayesian Video Dejittering By BV Image Model Jianhong Shen

    E-Print Network [OSTI]

    Bayesian Video Dejittering By BV Image Model Jianhong Shen School of Mathematics University horizontal displacement in video images, occurs when the synchronization signals are corrupted in video storage media, or by electro- magnetic interference in wireless video transmission. The goal of intrinsic

  16. Video Denoising and Simplification Via Discrete Regularization on Graphs

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Video Denoising and Simplification Via Discrete Regularization on Graphs Mahmoud Ghoniem, Youssef algorithms for video de- noising and simplification based on discrete regularization on graphs. The main difference between video and image denoising is the temporal redundancy in video sequences. Recent works

  17. Digital Video, Digital TV IMPA -Instituto de Matemtica Pura e

    E-Print Network [OSTI]

    1 Digital Video, Digital TV and Beyond Luiz Velho IMPA - Instituto de Matemática Pura e Aplicada 2 Outline Video in the Digital Age Deployment of Digital Video Enabling Technologies Research @ VISGRAF Laboratory Trends and the Future... 3 Evolution of Digital Video 1st Generation - Analog / Digital Conversion

  18. FEDERAL INSTITUTIONS AND POLICY STABILITY: THE ROLE OF FEDERALISM IN VETO PLAYERS THEORY

    E-Print Network [OSTI]

    Daehler, William Lawrence

    2014-05-31T23:59:59.000Z

    's (1999) measures of bicameralism. 4 is a majority that is more than 50 percent of a voting population. 2 The more veto players in a system, the greater the policy stability because it is more difficult to legislate changes to the status quo. Veto points...). The interests of each chamber are not a priori congruent because #16;constitutional veto players have independent power bases and sources of legitimation#17; (Roller, 2005: 90). While it is quite easy to identify the source of policy stability in bicameral...

  19. Wavelet Domain Based Techniques for Video Coding

    E-Print Network [OSTI]

    Kutil, Rade

    Wavelet Domain Based Techniques for Video Coding Dissertation zur Erlangung des Doktorgrades an der . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.4.3 Error Resilience . . . . . . . . . . . . . . . . . . . . . . . . 17 3 Wavelet Transform 18 3.1 Wavelet Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.1.1 Fourier Transform (FT

  20. Transforms for prediction residuals in video coding

    E-Print Network [OSTI]

    Kam??l?, Fatih

    2010-01-01T23:59:59.000Z

    Typically the same transform, the 2-D Discrete Cosine Transform (DCT), is used to compress both image intensities in image coding and prediction residuals in video coding. Major prediction residuals include the motion ...

  1. One Video Stream to Serve Diverse Receivers

    E-Print Network [OSTI]

    Woo, Grace

    2008-10-18T23:59:59.000Z

    The fundamental problem of wireless video multicast is to scalably serve multiple receivers which may have very different channel characteristics. Ideally, one would like to broadcast a single stream that allows each ...

  2. Steganalysis of video sequences using collusion sensitivity

    E-Print Network [OSTI]

    Budhia, Udit

    2006-08-16T23:59:59.000Z

    In this thesis we present an effective steganalysis technique for digital video sequences based on the collusion attack. Steganalysis is the process of detecting with a high probability the presence of covert data in multimedia. Existing algorithms...

  3. 77. Mudugar video documentaries, In their eyes...

    E-Print Network [OSTI]

    Alex, Rayson K.

    literature of an indigenous community called Mudugar. Mudugar live in the mountainous land of Attapady, Palakkad District, Kerala State, South India. The photographs, video-documentaries, audio files and translated interviews are materials collected over a...

  4. Eulerian Video Processing and medical applications

    E-Print Network [OSTI]

    Wu, Hao-Yu, M. Eng. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Our goal is to reveal subtle yet informative signals in videos that are difficult or impossible to see with the naked eye. We can either display them in an indicative manner, or analyse them to extract important measurements, ...

  5. Analyzing pulse from head motions in video

    E-Print Network [OSTI]

    Balakrishnan, Guha

    2014-01-01T23:59:59.000Z

    We extract heart rate and beat lengths from videos by measuring subtle head oscillations that accompany the cardiac cycle. Our method tracks features on the head, temporally filters their trajectories and performs principal ...

  6. A layered multicast packet video system

    E-Print Network [OSTI]

    Brown, Thomas B., 1969-

    1996-01-01T23:59:59.000Z

    Software based desktop videoconferencing tools are developed to demonstrate techniques necessary for video delivery in heterogeneous packet networks. Using the current network infrastructure and no network resource reservation, a one...

  7. Development of a three resolution video encoder

    E-Print Network [OSTI]

    Sazzad, Sharif Mohammad

    1995-01-01T23:59:59.000Z

    DEVELOPMENT OF A THREE RESOLUTION VIDEO ENCODER A Thesis by SHARIF MOHAMMAD SAZZAD Submitted to the Office of Graduate Studies of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December... 1995 Major Subject: Electrical Engineering DEVELOPMENT OF A THREE RESOLUTION VIDEO ENCODER A Thesis by SHARIF MOHAMMAD SAZZAD Submitted to Texas ARM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...

  8. Jamming Transition and Inherent Structures of Hard Spheres and Discs

    E-Print Network [OSTI]

    Misaki Ozawa; Takeshi Kuroiwa; Atsushi Ikeda; Kunimasa Miyazaki

    2012-11-17T23:59:59.000Z

    Recent studies show that volume fractions $\\phiJ$ at the jamming transition of frictionless hard spheres and discs are not uniquely determined but exist over a continuous range. Motivated by this observation, we numerically investigate dependence of $\\phiJ$ on the initial configurations of the parent fluids equilibrated at a fraction $\\phiini$, before compressing to generate a jammed packing. We find that $\\phiJ$ remains constant when $\\phiini$ is small but sharply increases when $\\phiini$ exceeds the dynamic transition point which the mode-coupling theory predicts. We carefully analyze configurational properties of both jammed packings and parent fluids and find that, while all jammed packings remain isostatic, the increase of $\\phiJ$ is accompanied with subtle but distinct changes of (i) local orders, (ii) a static length scale, and (iii) an exponent of the finite size scaling. These results quantitatively support the scenario of the random first order transition theoryof the glass transition.

  9. The Complete Jamming Landscape of Confined Hard Discs

    E-Print Network [OSTI]

    S. S. Ashwin; Richard k. Bowles

    2009-03-25T23:59:59.000Z

    An exact description of the complete jamming landscape is developed for a system of hard discs of diameter $\\sigma$, confined between two lines separated by a distance $1+\\sqrt{3/4} < H/\\sigma < 2$. By considering all possible local packing arrangements, the generalized ensemble partition function of jammed states is obtained using the transfer matrix method, which allows us to calculate the configurational entropy and the equation of state for the packings. Exploring the relationship between structural order and packing density, we find that the geometric frustration between local packing environments plays an important role in determining the density distribution of jammed states and that structural "randomness" is a non-monotonic function of packing density. Molecular dynamics simulations show that the properties of the equilibrium liquid are closely related to those of the landscape.

  10. Normal modes analysis of the microscopic dynamics in hard discs

    E-Print Network [OSTI]

    Carolina Brito; Matthieu Wyart

    2008-05-09T23:59:59.000Z

    We estimate numerically the normal modes of the free energy in a glass of hard discs. We observe that, near the glass transition or after a rapid quench deep in the glass phase, the density of states (i) is characteristic of a marginally stable structure, in particular it di splays a frequency scale $\\omega^*\\sim p^{1/2}$, where $p$ is the pressure and (ii) gives a faithful representation of the short-time dyn amics. This brings further evidences that the boson peak near the glass transition corresponds to the relaxation of marginal modes of a we akly-coordinated structure, and implies that the mean square displacement in the glass phase is anomalously large and goes as $ \\sim p^{-3/2}$, a prediction that we check numerically.

  11. Appendix D: Video Analysis of Motion Analyzing pictures (movies or videos) is a powerful tool for understanding how objects move.

    E-Print Network [OSTI]

    Minnesota, University of

    D - 1 Appendix D: Video Analysis of Motion Analyzing pictures (movies or videos) is a powerful tool for understanding how objects move. Like most forms of data, video is most easily analyzed using a computer and data of one such program: the video analysis application written in LabVIEWTM. LabVIEWTM is a general

  12. Video Games and Mathematics Education: Studying Commercial Sports Video Games to Identify the Potential for Learning and Thinking About

    E-Print Network [OSTI]

    Spagnolo, Filippo

    Video Games and Mathematics Education: Studying Commercial Sports Video Games to Identify What happens when commercial sports video games, designed for entertainment, are used in an effort is an attempt to examine the potential for connecting digital media (sports video games) to learning various

  13. Hydrogenated Nanocrystalline Silicon p-Layer in a-Si:H n-i-p Solar Cells Wenhui Dua)

    E-Print Network [OSTI]

    Deng, Xunming

    Hydrogenated Nanocrystalline Silicon p-Layer in a-Si:H n-i-p Solar Cells Wenhui Dua) , Xianbo Liaob hydrogenated amorphous silicon (a-Si:H) solar cells. Raman scattering spectroscopy and transmission electron). Using this kind of p-layer in n-i-p a-Si:H solar cells, the cell performances were improved with a Voc

  14. FINE-GRAINED NANOCRYSTALLINE SILICON P-LAYER FOR HIGH OPEN CIRCUIT VOLTAGE A-SI:H SOLAR CELLS

    E-Print Network [OSTI]

    Deng, Xunming

    FINE-GRAINED NANOCRYSTALLINE SILICON P-LAYER FOR HIGH OPEN CIRCUIT VOLTAGE A-SI:H SOLAR CELLS of Michigan, Ann Arbor, MI 48109, USA ABSTRACT Hydrogenated amorphous silicon (a-Si:H) single- junction solar). It is found that the p-layer that leads to high Voc a-Si:H solar cells is a mixed-phase material that contains

  15. Overcoming challenges: Going mobile with your own video models.

    E-Print Network [OSTI]

    Carnahan, Christina R.; Basham, James D.; Christman, Jennifer; Hollingshead, Aleksandra

    2012-01-01T23:59:59.000Z

    Web 2.0 a Ö 5 Overcoming Challenges Going Mobile With Your Own Video Models Christina R. Carnahan, James D. Basham, Jennifer Christman, and Aleksandra HoUingshead Ms. Heller is a middle school interveh- tion specialist who is planning weekly trtps... with disabilities. Video modeling is one such instructional techniciue. Essentially, video inodeling provides students with a video that illustrates the context and steps required to com- plete a desired behavior (Bellini, AkuUian, & Hopf, 2007). Traditional video...

  16. Massive planets in FU Orionis discs: implications for thermal instability models

    E-Print Network [OSTI]

    G. Lodato; C. J. Clarke

    2004-06-10T23:59:59.000Z

    FU Orionis are young stellar objects undergoing episodes of enhanced luminosity, which are generally ascribed to a sudden increase of mass accretion rate in the surrounding protostellar disc. Models invoking a thermal instability in the disc are able to reproduce many features of the outburst, but cannot explain the rapid rise time-scale observed in many cases. Here we explore the possibility (originally suggested by Clarke & Syer 1996) that the thermal instability is triggered away from the disc inner edge (at a distance of $\\approx 10R_{\\odot}$ from the central protostar) due to the presence of a massive planet embedded in the disc. We have constructed simple, one-dimensional, time-dependent models of the disc evolution, taking into account both the interaction between the disc and the planet, and the thermal evolution of the disc. We are indeed able to reproduce rapid rise outbursts (with rise time-scale $\\approx 1$ yr), with a planet mass $M_{\\mathrm{s}}=10-15M_{\\mathrm{Jupiter}}$. We show that the luminosity and the duration of the outbursts are increasing functions of planet mass. We also show that the inward migration of the planet is significantly slowed once it reaches the radius where it is able to trigger FU Orionis outbursts, thus suggesting that a single planet may be involved in triggering several outbursts.

  17. On fan-shaped cold MHD winds from Keplerian accretion discs

    E-Print Network [OSTI]

    Ferreira, Jonathan

    2012-01-01T23:59:59.000Z

    We investigate under which conditions cold, fan-shaped winds can be steadily launched from thin (Keplerian) accretion discs. Such winds are magneto-centrifugal winds launched from a thin annulus in the disc, along open magnetic field lines that fan out above the disc. In principle, such winds could be found in two situations: (1) at the interface between an inner Jet Emitting Disc, which is itself powering magneto-centrifugally driven winds, and an outer standard accretion disc; (2) at the interface between an inner closed stellar magnetosphere and the outer standard accretion disc. We refer to Terminal or T-winds to the former kind and to Magnetospheric or M-winds to the latter. The full set of resistive and viscous steady state MHD equations are analyzed for the disc (the annulus), which allow us to derive general expressions valid for both configurations. We find that, under the framework of our analysis, the only source of energy able to power any kind of fan-shaped winds is the viscous transport of rotat...

  18. High accretion rates in magnetised Keplerian discs mediated by a Parker instability driven dynamo

    E-Print Network [OSTI]

    Anders Johansen; Yuri Levin

    2008-08-26T23:59:59.000Z

    Hydromagnetic stresses in accretion discs have been the subject of intense theoretical research over the past one and a half decades. Most of the disc simulations have assumed a small initial magnetic field and studied the turbulence that arises from the magnetorotational instability. However, gaseous discs in galactic nuclei and in some binary systems are likely to have significant initial magnetisation. Motivated by this, we performed ideal magnetohydrodynamic simulations of strongly magnetised, vertically stratified discs in a Keplerian potential. Our initial equilibrium configuration, which has an azimuthal magnetic field in equipartion with thermal pressure, is unstable to the Parker instability. This leads to the expelling of magnetic field arcs, anchored in the midplane of the disc, to around five scale heights from the midplane. Transition to turbulence happens primarily through magnetorotational instability in the resulting vertical fields, although magnetorotational shear instability in the unperturbed azimuthal field plays a significant role as well, especially in the midplane where buoyancy is weak. High magnetic and hydrodynamical stresses arise, yielding an effective $\\alpha$-value of around 0.1 in our highest resolution run. Azimuthal magnetic field expelled by magnetic buoyancy from the disc is continuously replenished by the stretching of a radial field created as gas parcels slide in the linear gravity field along inclined magnetic field lines. This dynamo process, where the bending of field lines by the Parker instability leads to re-creation of the azimuthal field, implies that highly magnetised discs are astrophysically viable and that they have high accretion rates.

  19. Eccentricity growth of planetesimals in a self-gravitating protoplanetary disc

    E-Print Network [OSTI]

    M. Britsch; C. J. Clarke; G. Lodato

    2008-01-14T23:59:59.000Z

    We investigate the orbital evolution of planetesimals in a self-gravitating circumstellar disc in the size regime ($\\sim 1-5000$ km) where the planetesimals behave approximately as test particles in the disc's non-axisymmetric potential. We find that the particles respond to the stochastic, regenerative spiral features in the disc by executing large random excursions (up to a factor of two in radius in $\\sim 1000$ years), although typical random orbital velocities are of order one tenth of the Keplerian speed. The limited time frame and small number of planetesimals modeled does not permit us to discern any {\\it net} direction of planetesimal migration. Our chief conclusion is that the high eccentricities ($\\sim 0.1$) induced by interaction with spiral features in the disc is likely to be highly unfavourable to the collisional growth of planetesimals in this size range while the disc is in the self-gravitating regi me. Thus {\\it if}, as recently argued by Rice et al 2004, 2006, the production of planetesimals gets under way when the disc is in the self-gravitating regime (either at smaller planetesimal size scales, where gas drag is important, or via gravitational fragmentation of the solid component), then the planetesimals thus produced would not be able to grow collisionally until the disc ceased to be self-gravitating. It is unclear, however,given the large amplitude excursions undergone by planetesimals in the self-gravitating disc, whether they would be retained in the disc throughout this period, or whether they would instead be lost to the central star.

  20. Storm fronts over galaxy discs: Models of how waves generate extraplanar gas and its anomalous kinematics

    E-Print Network [OSTI]

    Curtis Struck; Daniel C. Smith

    2009-05-15T23:59:59.000Z

    The existence of partially ionized, diffuse gas and dust clouds at kiloparsec scale distances above the central planes of edge-on, galaxy discs was an unexpected discovery about 20 yrs ago. Subsequent observations showed that this EDIG (extended or extraplanar diffuse interstellar gas) has rotation velocities approximately 10-20% lower than those in the central plane, and have been hard to account for. Here we present results of hydrodynamic models, with radiative cooling and heating from star formation. We find that in models with star formation generated stochastically across the disc an extraplanar gas layer is generated as long as the star formation is sufficiently strong. However, this gas rotates at nearly the same speed as the mid-plane gas. We then studied a range of models with imposed spiral or bar waves in the disc. EDIG layers were also generated in these models, but primarily over the wave regions, not over the entire disc. Because of this partial coverage, the EDIG clouds move radially, as well as vertically, with the result that observed kinematic anomalies are reproduced. The implication is that the kinematic anomalies are the result of three-dimensional motions when the cylindrical symmetry of the disc is broken. Thus, the kinematic anomalies are the result of bars or strong waves, and more face-on galaxies with such waves should have an asymmetric EDIG component. The models also indicate that the EDIG can contain a significant fraction of cool gas, and that some star formation can be triggered at considerable heights above the disc midplane. We expect all of these effects to be more prominent in young, forming discs, to play a role in rapidly smoothing disc asymmetries, and in working to self-regulate disc structure.

  1. Maximally Random Jamming of Two-Dimensional One-Component and Binary Hard Disc Fluids

    E-Print Network [OSTI]

    Xinliang Xu; Stuart A. Rice

    2010-10-05T23:59:59.000Z

    We report calculations of the density of maximally random jamming (aka random close packing) of one-component and binary hard disc fluids. The theoretical structure used provides a common framework for description of the hard disc liquid to hexatic, the liquid to hexagonal crystal and the liquid-to-maximally random jammed state transitions. Our analysis is based on locating a particular bifurcation of the solutions of the integral equation for the inhomogeneous single particle density at the transition between different spatial structures. The bifurcation of solutions we study is initiated from the dense metastable fluid, and we associate it with the limit of stability of the fluid, which we identify with the transition from the metastable fluid to a maximally random jammed state. For the one-component hard disc fluid the predicted packing fraction at which the metastable fluid to maximally random jammed state transition occurs is 0.84, in excellent agreement with the experimental value 0.84 \\pm 0.02. The corresponding analysis of the limit of stability of a binary hard disc fluid with specified disc diameter ratio and disc composition requires extra approximations in the representations of the direct correlation function, the equation of state, and the number of order parameters accounted for. Keeping only the order parameter identified with the largest peak in the structure factor of the highest density regular lattice with the same disc diameter ratio and disc composition as the binary fluid, the predicted density of maximally random jamming is found to be 0.84 to 0.87, depending on the equation of state used, and very weakly dependent on the ratio of disc diameters and the fluid composition, in agreement with both experimental data and computer simulation data.

  2. On the accumulation of solid bodies in global turbulent protoplanetary disc models

    E-Print Network [OSTI]

    Sebastien Fromang; Richard P. Nelson

    2005-09-23T23:59:59.000Z

    We study the migration of solid bodies in turbulent protoplanetary accretion discs by means of global MHD simulations. The bodies range in size from 5 centimetres up to 1 metre, and so include objects whose migration is expected to be the most rapid due to gas drag interaction with the disc. As they drift inward through the disc, some of them are trapped in regions where gas pressure maxima are created by long lived anticyclonic vortices. This accumulation is very efficient, locally increasing the dust--to--gas ratio by a factor > 100 in some cases. We discuss the possible implications of this result for theories of planet formation.

  3. A viscous-convective instability in laminar Keplerian thin discs. II. Anelastic approximation

    E-Print Network [OSTI]

    Shakura, N

    2015-01-01T23:59:59.000Z

    Using the anelastic approximation of linearised hydrodynamic equations, we investigate the development of axially symmetric small perturbations in thin Keplerian discs. The sixth-order dispersion equation is derived and numerically solved for different values of relevant physical parameters (viscosity, heat conductivity, disc semi-thickness and vertical structure). The analysis reveals the appearance of two overstable modes which split out from the classical Rayleigh inertial modes in a wide range of the parameters in both ionized and neutral gases. These modes have a viscous-convective nature and can serve as a seed for turbulence in astrophysical discs even in the absence of magnetic fields.

  4. DESIGN CRITIQUE INSIDE A MULTI-PLAYER GAME ENGINE Jules Moloney

    E-Print Network [OSTI]

    Amor, Robert

    critique process, used to provide expert feedback on a building design concept to students in architectureDESIGN CRITIQUE INSIDE A MULTI-PLAYER GAME ENGINE Jules Moloney School of Architecture, University@cs.auckland.ac.nz Jay Furness and Benjamin Moores School of Engineering, University of Auckland SUMMARY The design

  5. Brazil is a major international player in the carbon markets that function under the UN Framework

    E-Print Network [OSTI]

    Brazil is a major international player in the carbon markets that function under the UN Framework projects. In addition, Brazil ranks third after China and India in the generation of CDM certi- fied of the CDM in terms of the magnitude of carbon credits gen- erated and the relatively rigorous application

  6. Player Modeling: Towards a Common Taxonomy Marlos C. Machado, Eduardo P. C. Fantini and Luiz Chaimowicz

    E-Print Network [OSTI]

    Chaimowicz, Luiz

    Player Modeling: Towards a Common Taxonomy Marlos C. Machado, Eduardo P. C. Fantini and Luiz of the field, discussing the main concepts and proposing a taxonomy to better organize them. We also present, Taxonomy, Game Platforms. I. INTRODUCTION For a long time, the game industry has put much of its efforts

  7. Optimization of platform game levels for player experience Chris Pedersen, Julian Togelius, Georgios Yannakakis

    E-Print Network [OSTI]

    Togelius, Julian

    Platform game The test-bed platform game used for our studies is a ver- sion of Infinite Mario Bros (seeOptimization of platform game levels for player experience Chris Pedersen, Julian Togelius of certain parameters of platform game levels on the play- ers' experience of the game. A version of Super

  8. Page 1 of 2 How to Upload Videos to YouTube

    E-Print Network [OSTI]

    Engel, Robert

    Page 1 of 2 How to Upload Videos to YouTube To submit a video to the event, you should make a 30-to-60-second video. You can use your cell phone, a video camera, your webcam, or other sources for your video. You can use various video editing programs to make your video, including iMovie (on Macs

  9. An Artificial Intelligence system to help the player of Real-Time Strategy games Renato L. de Freitas Cunha Luiz Chaimowicz

    E-Print Network [OSTI]

    Chaimowicz, Luiz

    An Artificial Intelligence system to help the player of Real-Time Strategy games Renato L. de propose and develop an Artificial Intelligence (AI) system that helps the player during the game, giving and develop an Artificial Intelligence (AI) system that helps the player during the game, giving him tactical

  10. Integrating Geometric, Motion and Appearance Constraints for Robust Tracking in Aerial Videos

    E-Print Network [OSTI]

    Hasan, Mahmudul

    2013-01-01T23:59:59.000Z

    P. Pan and D. Schonfeld, “Video tracking based on sequentialand S. Mubarak, “Simultaneous video stabilization and movingAlgorithm 2: GMAC aerial video tracking Data: Unstable

  11. Video packet loss visibility models and their application to packet prioritization

    E-Print Network [OSTI]

    Lin, Ting-Lan

    2010-01-01T23:59:59.000Z

    of the subjective experiment setup for SD and HD videos.of the video. . . . . . . . . . . . . . . . . . . Table V.2:allocation for perceptual video quality . . . . . . . A.

  12. A collagen-GAG matrix for the growth of intervertebral disc tissue

    E-Print Network [OSTI]

    Hastreiter, Dawn (Dawn Marie), 1973-

    2002-01-01T23:59:59.000Z

    Intervertebral disc (IVD) degeneration and herniation is a significant problem, more so in the aviation field. The IVD also changes during spaceflight. Current treatments for IVD problems can have unfavorable long-term ...

  13. Retinal imaging tool for assessment of the parapapillary atrophy and the optic disc 

    E-Print Network [OSTI]

    Lu, Cheng-Kai

    2012-11-29T23:59:59.000Z

    Ophthalmic diseases such as glaucoma are associated with progressive changes in the structure of the optic disc (OD) and parapapillary atrophy (PPA). These structural changes may therefore have relevance to other systemic ...

  14. E-Print Network 3.0 - accretion disc variability Sample Search...

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

    370, L61L65 (2006) doi:10.1111j.1745-3933.2006.00189.x The late time evolution of gamma-ray bursts: ending hyperaccretion Summary: of GRBs. Key words: accretion, accretion discs -...

  15. Spectra of disc operator for twisted acceleration-enlarged Newton-Hooke space-times

    E-Print Network [OSTI]

    Marcin Daszkiewicz

    2011-01-10T23:59:59.000Z

    The time-dependent spectra of disc area operator for twisted acceleration-enlarged Newton-Hooke space-times are derived. It is demonstrated that the corresponding area quanta are expanding or oscillating in time.

  16. NDE1 in the DISC1 pathway: interactions of schizophrenia-related proteins 

    E-Print Network [OSTI]

    Bradshaw, Nicholas James

    2009-01-01T23:59:59.000Z

    The Disrupted-In-Schizophrenia 1 (DISC1) gene is one of the most established risk genes for psychiatric illness currently being studied, having originally been identified as being directly disrupted by a balanced chromosomal ...

  17. Dynamics of perturbation modes in protoplanetary discs : new effects of self-gravity and velocity shear 

    E-Print Network [OSTI]

    Mamatsashvili, George

    2011-06-27T23:59:59.000Z

    Protoplanetary discs, composed of gas and dust, usually surround young stellar objects and serve two main purposes: they determine the accretion of matter onto the central object and also represent sites of planet ...

  18. Quantum McKay correspondence for disc invariants of toric Calabi-Yau 3-orbifolds

    E-Print Network [OSTI]

    Hua-Zhong Ke; Jian Zhou

    2014-10-16T23:59:59.000Z

    We announce a result on quantum McKay correspondence for disc invariants of outer legs in toric Calabi-Yau 3-orbifolds, and illustrate our method in a special example $[\\mathbb C^3 /\\mathbb Z_5 (1, 1, 3)]$.

  19. Spectral Evolution of the Continuum and Disc Line in Dipping in GRO J1655-40

    E-Print Network [OSTI]

    M. Balucinska-Church

    2001-01-22T23:59:59.000Z

    The discovery is reported of emission features in the X-ray spectrum of GRO J1655-40 obtained using Rossi-XTE on 1997, Feb 26. The features have been fitted firstly by two Gaussian lines, which in four spectra have average energies of 5.85+/-0.08 keV and 7.32+/-0.13 keV, strongly suggestive that these are the red- and blueshifted wings of an iron disc line from material with velocity ~0.33 c. The blue wing is apparently less bright than expected for a disc line subject to Doppler boosting, however, known absorption in the spectrum of GRO J1655-40 at energies between ~7 and 8 keV can reduce the apparent brightness of the blue wing. The spectra have also been fitted well using the full relativistic disc line model of Laor, plus an absorption line. This gives a restframe energy between 6.4 and 6.8 keV indicating that the line is from highly ionized iron K_alpha. The Laor model also shows that the line originates at radii extending from ~10 Schwarzschild radii (r_S) outwards. The line is direct evidence for the black hole nature of the compact object. The continuum is well described by dominant disc blackbody emission plus Comptonized emission. During dipping, spectral evolution is well modelled by allowing progressive covering of the disc blackbody and simple absorption of the Comptonized emission showing that the thermal emission is more extended. Acceptable fits are only obtained by including the disc line in the covering term, indicating that it originates in the same inner disc region as the thermal continuum. Dip ingress times and durations are used to provide the radius of the disc blackbody emitter as 170-370 r_S, and the radius of the absorber.

  20. Hard discs under steady shear: comparison of Brownian dynamics simulations and mode coupling theory

    E-Print Network [OSTI]

    O. Henrich; F. Weysser; M. E. Cates; M. Fuchs

    2010-01-19T23:59:59.000Z

    Brownian dynamics simulations of bidisperse hard discs moving in two dimensions in a given steady and homogeneous shear flow are presented close to and above the glasstransition density. The stationary structure functions and stresses of shear-melted glass are compared quantitatively to parameter-free numerical calculations of monodisperse hard discs using mode coupling theory within the integration through transients framework. Theory qualitatively explains the properties of the yielding glass but quantitatively overestimatesthe shear-driven stresses and structural anisotropies.

  1. Secular resonant dressed orbital diffusion II : application to an isolated self similar tepid galactic disc

    E-Print Network [OSTI]

    Fouvry, Jean-Baptiste

    2015-01-01T23:59:59.000Z

    The main orbital signatures of the secular evolution of an isolated self-gravitating stellar Mestel disc are recovered using a dressed Fokker-Planck formalism in angle-action variables. The shot-noise-driven formation of narrow ridges of resonant orbits is recovered in the WKB limit of tightly wound transient spirals, for a tepid Toomre-stable tapered disc. The relative effect of the bulge, the halo, the disc temperature and the spectral properties of the shot noise are investigated in turn. For such galactic discs all elements seem to impact the locus and direction of the ridge. For instance, when the halo mass is decreased, we observe a transition between a regime of heating in the inner regions of the disc through the inner Lindblad resonance to a regime of radial migration of quasi-circular orbits via the corotation resonance in the outer part of the disc. The dressed secular formalism captures both the nature of collisionless systems (via their natural frequencies and susceptibility), and their nurture v...

  2. Searching for the metal-weak thick disc in the solar neighbourhood

    E-Print Network [OSTI]

    Bacham E. Reddy; David L. Lambert

    2008-09-05T23:59:59.000Z

    An abundance analysis is presented of 60 metal-poor stars drawn from catalogues of nearby stars provided by Ariyanto et al. (2005) and Schuster et al. (2006). In an attempt to isolate a sample of metal-weak thick disc stars, we applied the kinematic criteria $V_{\\rm rot} \\geq 100$ km s$^{-1}$, $|U_{LSR}| \\leq 140$ km s$^{-1}$, and $|W_{LSR}| \\leq 100$ km s$^{-1}$. Fourteen stars satisfying these criteria and having [Fe/H] $\\leq -1.0$ are included in the sample of 60 stars. Eight of the 14 have [Fe/H] $\\geq -1.3$ and may be simply thick disc stars of slightly lower than average [Fe/H]. The other six have [Fe/H] from -1.3 to -2.3 and are either metal-weak thick disc stars or halo stars with kinematics mimicking those of the thick disc. The sample of 60 stars is completed by eight thick disc stars, 20 stars of a hybrid nature (halo or thick disc stars), and 18 stars with kinematics distinctive of the halo.

  3. One-armed spirals in locally isothermal, radially structured self-gravitating discs

    E-Print Network [OSTI]

    Lin, Min-Kai

    2015-01-01T23:59:59.000Z

    We describe a new mechanism that leads to the destabilisation of non-axisymmetric waves in astrophysical discs with an imposed radial temperature gradient. This might apply, for example, to the outer parts of protoplanetary discs. We use linear density wave theory to show that non-axisymmetric perturbations generally do not conserve their angular momentum in the presence of a forced temperature gradient. This implies an exchange of angular momentum between linear perturbations and the background disc. In particular, when the disturbance is a low-frequency trailing wave and the disc temperature decreases outwards, this interaction is unstable and leads to the growth of the wave. We demonstrate this phenomenon through numerical hydrodynamic simulations of locally isothermal discs in 2D using the FARGO code and in 3D with the ZEUS-MP and PLUTO codes. We consider radially structured discs with a self-gravitating region which remains stable in the absence of a temperature gradient. However, when a temperature grad...

  4. The Gaia-ESO Survey: Insights on the inner-disc evolution from open clusters

    E-Print Network [OSTI]

    Magrini, L; Donati, P; Bragaglia, A; Adibekyan, V; Romano, D; Smiljanic, R; Blanco-Cuaresma, S; Tautvaisiene, G; Friel, E; Overbeek, J; Jacobson, H; Cantat-Gaudin, T; Vallenari, A; Sordo, R; Pancino, E; Geisler, D; Roman, I San; Villanova, S; Casey, A; Hourihane, A; Worley, C C; Francois, P; Gilmore, G; Bensby, T; Flaccomio, E; Korn, A J; Recio-Blanco, A; Carraro, G; Costado, M T; Franciosini, E; Heiter, U; Jofree, P; Lardo, C; de Laverny, P; Monaco, L; Morbidelli, L; Sacco, G; Sousa, S G; Zaggia, S

    2015-01-01T23:59:59.000Z

    Context. The inner disc, linking the thin disc with the bulge, has been somehow neglected in the past because of intrinsic difficulties in its study, due, e.g., to crowding and high extinction. Open clusters located in the inner disc are among the best tracers of its chemistry at different ages and distances. Aims. We analyse the chemical patterns of four open clusters located within 7 kpc of the Galactic Centre and of field stars to infer the properties of the inner disc with the Gaia-ESO survey idr2/3 data release. Methods. We derive the parameters of the newly observed cluster, Berkeley 81, finding an age of about 1 Gyr and a Galactocentric distance of 5.4 kpc. We construct the chemical patterns of clusters and we compare them with those of field stars in the Solar neighbourhood and in the inner-disc samples. Results. Comparing the three populations we observe that inner-disc clusters and field stars are both, on average, enhanced in [O/Fe], [Mg/Fe] and [Si/Fe]. Using the idr2/3 results of M67, we estimate...

  5. Liberation of specific angular momentum through radiation and scattering in relativistic black hole accretion discs

    E-Print Network [OSTI]

    Adam R. H. Stevens

    2015-02-26T23:59:59.000Z

    A key component of explaining the array of galaxies observed in the Universe is the feedback of active galactic nuclei, each powered by a massive black hole's accretion disc. For accretion to occur, angular momentum must be lost by that which is accreted. Electromagnetic radiation must offer some respite in this regard, the contribution for which is quantified in this paper using solely general relativity under the thin-disc regime. Herein, I calculate extremised situations where photons are entirely responsible for energy removal in the disc and then extend and relate this to the standard relativistic accretion disc outlined by Novikov & Thorne that includes the effect of viscosity. While there is potential for the contribution of angular-momentum removal from photons to be >~1% out to ~10^4 Schwarzschild radii, especially if the disc is irradiated and is liberated of angular momentum through scattering, it is more likely of order 10^2 Schwarzschild radii if thermal emission from the disc itself is stronger. Near the horizons of fast-spinning black holes, these modes of angular-momentum liberation become dominant.

  6. Emergent Mesoscale Phenomena in Magnetized Accretion Disc Turbulence

    E-Print Network [OSTI]

    Simon, Jacob B; Armitage, Philip J

    2012-01-01T23:59:59.000Z

    We study how the structure and variability of magnetohydrodynamic (MHD) turbulence in accretion discs converge with domain size. Our results are based on a series of vertically stratified local simulations, computed using the Athena code, that have fixed spatial resolution, but varying radial and azimuthal extent (from \\Delta R = 0.5H to 16H, where H is the vertical scale height). We show that elementary local diagnostics of the turbulence, including the Shakura-Sunyaev {\\alpha} parameter, the ratio of Maxwell stress to magnetic energy, and the ratio of magnetic to fluid stresses, converge to within the precision of our measurements for spatial domains of radial size Lx \\geq 2H. We obtain {\\alpha} = 0.02-0.03, consistent with recent results. Very small domains (Lx = 0.5H) return anomalous results, independent of spatial resolution. The convergence with domain size is only valid for a limited set of diagnostics: larger spatial domains admit the emergence of dynamically important mesoscale structures. In our la...

  7. Measuring the configurational temperature of a binary disc packing

    E-Print Network [OSTI]

    Song-Chuan Zhao; Matthias Schröter

    2014-06-20T23:59:59.000Z

    Jammed packings of granular materials differ from systems normally described by statistical mechanics in that they are athermal. In recent years a statistical mechanics of static granular media has emerged where the thermodynamic temperature is replaced by a configurational temperature X which describes how the number of mechanically stable configurations depends on the volume. Four different methods have been suggested to measure X. Three of them are computed from properties of the Voronoi volume distribution, the fourth takes into account the contact number and the global volume fraction. This paper answers two questions using experimental binary disc packings: First we test if the four methods to measure compactivity provide identical results when applied to the same dataset. We find that only two of the methods agree quantitatively. Secondly, we test if X is indeed an intensive variable; this becomes true only for samples larger than roughly 200 particles. This result is shown to be due to recently found correlations between the particle volumes [Zhao et al., Europhys. Lett., 2012, 97, 34004].

  8. Survival and Structure of Dusty Vortices in Protoplanetary Discs

    E-Print Network [OSTI]

    Crnkovic-Rubsamen, Ivo; Stone, James M

    2015-01-01T23:59:59.000Z

    We have studied the impact of dust feedback on the survival and structure of vortices in protoplanetary discs using 2-D shearing box simulations with Lagrangian dust particles. We consider dust with a variety of sizes (stopping time $t_s = 10^{-2}\\Omega^{-1} - 10^{2}\\Omega^{-1}$, from fully coupled with the gas to the decoupling limit. We find that a vortex is destroyed by dust feedback when the total dust-to-gas mass ratio within the vortex is larger than 30-50%, independent of the dust size. The dust distribution can still be asymmetric in some cases after the vortex has been destroyed. With smaller amounts of dust, a vortex can survive for at least 100 orbits, and the maximum dust surface density within the vortex can be more than 100 times larger than the gas surface density, potentially facilitating planetesimal formation. On the other hand, in these stable vortices, small ($t_s \\Omega^{-1}$) dust grains concentrate differently and affect the gas dynamics in different ways. The distribution of large dus...

  9. Jammed frictionless discs: connecting local and global response

    E-Print Network [OSTI]

    Wouter G. Ellenbroek; Martin van Hecke; Wim van Saarloos

    2009-11-04T23:59:59.000Z

    By calculating the linear response of packings of soft frictionless discs to quasistatic external perturbations, we investigate the critical scaling behavior of their elastic properties and non-affine deformations as a function of the distance to jamming. Averaged over an ensemble of similar packings, these systems are well described by elasticity, while in single packings we determine a diverging length scale $\\ell^*$ up to which the response of the system is dominated by the local packing disorder. This length scale, which we observe directly, diverges as $1/\\Delta z$, where $\\Delta z$ is the difference between contact number and its isostatic value, and appears to scale identically to the length scale which had been introduced earlier in the interpretation of the spectrum of vibrational modes. It governs the crossover from isostatic behavior at the small scale to continuum behavior at the large scale; indeed we identify this length scale with the coarse graining length needed to obtain a smooth stress field. We characterize the non-affine displacements of the particles using the \\emph{displacement angle distribution}, a local measure for the amount of relative sliding, and analyze the connection between local relative displacements and the elastic moduli.

  10. Video sculpture:spatio-temporal warping

    E-Print Network [OSTI]

    Groves, Jeff David

    2004-09-30T23:59:59.000Z

    of Committee) Carol LaFayette (Member) John Keyser (Member) Phillip Tabb (Head of Department) December 2003 Major Subject: Visualization Sciences iii ABSTRACT Video Sculpture: Spatio-temporal Warping. (December 2003) Jeff Groves, B.S., Portland State University..., 2002. [22] J. Groves, Journeys in Space and Time. digital video, 2003. 35 VITA Jeff Groves 1402 Kirkwood Unit A Austin, TX 78722 jgroves@viz.tamu.edu Education M.S. in Visualization Sciences Texas A&M University, 12/03 B.S. in Architecture Portland...

  11. Latest Feature Video | The Ames Laboratory

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > The Energy MaterialsFeatured VideosTechnologiesLatest Feature Video

  12. Videos | Y-12 National Security Complex

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1 - USAFofEmail Mr. WilliamVideo: Watch theVideos

  13. HMDB: A Large Video Database for Human Motion Recognition

    E-Print Network [OSTI]

    Kuehne, H.

    With nearly one billion online videos viewed everyday, an emerging new frontier in computer vision research is recognition and search in video. While much effort has been devoted to the collection and annotation of large ...

  14. Digital Video in Education MAJ Todd L. Smith

    E-Print Network [OSTI]

    Jansen, James

    Digital Video in Education MAJ Todd L. Smith D/EECS, US Military Academy West Point, NY 10996 dt: Smith, T. L., Ruocco, A., and Jansen, B.J. 1999. Digital video in education, ACM Computer Science

  15. Algorithms for transform selection in multiple-transform video compression

    E-Print Network [OSTI]

    Cai, Xun, S.M. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Selecting proper transforms for video compression has been based on the rate-distortion criterion. Transforms that appear reasonable are incorporated into a video coding system and their performance is evaluated. This ...

  16. Game worlds : a study of video game criticism

    E-Print Network [OSTI]

    Gursoy, Ayse

    2013-01-01T23:59:59.000Z

    This paper explores the relation between criticism and establishment of narrative forms and genres, focusing on the cultural situation of video games. Comparing the context of early film criticism and contemporary video ...

  17. ChitChat : making video chat robust to packet loss

    E-Print Network [OSTI]

    Wang, Jue, 1986-

    2010-01-01T23:59:59.000Z

    Video chat is increasingly popular among Internet users (e.g. Skype, Windows Live Messenger, Google Talk). Often, however, chatting sessions suffer from packet loss, which causes video outage and poor quality. Existing ...

  18. Video Installation Design: Appropriation and Assemblage As Projection Surface Geometry

    E-Print Network [OSTI]

    Weaver, Timothy A.

    2010-07-14T23:59:59.000Z

    This area of research focuses on the use of video projections in the context of fine art. Emphasis is placed on creating a unique video installation work that incorporates assemblage and appropriation as a means to develop multiple complex...

  19. SoftCast: Clean-slate Scalable Wireless Video

    E-Print Network [OSTI]

    Jakubczak, Szymon

    2011-02-15T23:59:59.000Z

    Video broadcast and mobile video challenge the conventional wireless design. In broadcast and mobile scenarios the bit rate supported by the channel differs across receivers and varies quickly over time. The conventional ...

  20. An environmental change detection and analysis tool using terrestrial video

    E-Print Network [OSTI]

    Velez, Javier, M. Eng. Massachusetts Institute of Technology

    2006-01-01T23:59:59.000Z

    We developed a prototype system to detect and flag changes between pairs of geo-tagged videos of the same scene with similar camera trajectories. The purpose of the system is to help human video analysts detect threats ...

  1. ChitChat: Making Video Chat Robust to Packet Loss

    E-Print Network [OSTI]

    Wang, Jue

    2010-07-05T23:59:59.000Z

    Video chat is increasingly popular among Internet users. Often, however, chatting sessions suffer from packet loss, which causes video outage and poor quality. Existing solutions however are unsatisfying. Retransmissions ...

  2. Creating Automated Interactive Video Playback for Studies of Animal Communications

    E-Print Network [OSTI]

    Butkowski, Trisha

    2010-01-16T23:59:59.000Z

    Video playback is a technique used to study the visual communication and behaviors of animals. While video playback is a useful tool, most experiments lack the ability for the visual stimulus to interact with the live animal. The limited number...

  3. Mining data on usage of electronic nicotine delivery systems (ENDS) from YouTube videos

    E-Print Network [OSTI]

    Talbot, Prue

    2013-01-01T23:59:59.000Z

    systems (ENDS) from YouTube videos My Hua, Henry Yip, PrueENDS) and conventional cigarettes in YouTube videos.Methods Video data from YouTube videos were analysed to

  4. Video Rental Store: An Interview with Suzanne Carte-Blanchenot and Su-Ying Lee

    E-Print Network [OSTI]

    Hogan, Mél

    2010-01-01T23:59:59.000Z

    Video Rental Store An Interview with Suzanne Carte-of Under New Management’s Video Rental Store in Toronto,by the project’s name, Video Rental Store takes on the video

  5. Text-Alternative Version: Smithsonian GATEWAY Demonstration Video

    Broader source: Energy.gov [DOE]

    Following is a text version of a video about the GATEWAY demonstration project at the Smithsonian American Art Museum.

  6. Orchestrating Market Success: Seattle Market Introduction Workshop Video

    Broader source: Energy.gov [DOE]

    View the video from Jim Brodrick's opening presentation at the July 2011 DOE SSL Market Introduction Workshop in Seattle, Washington.

  7. Video Mining with Frequent Itemset Configurations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Video Mining with Frequent Itemset Configurations Till Quack1 , Vittorio Ferrari2 , and Luc Van Gool1 1 ETH Zurich 2 LEAR - INRIA Grenoble Abstract. We present a method for mining frequently arrangements of affine covariant regions. Our mining method is based on the class of frequent itemset mining

  8. Challenges of Video Monitoring for Phenomenological Diagnostics

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . This platform has been validated on Tore Supra during operation and is under evaluation for the foreseen imaging. As a consequence, present Tokamaks are equipped and/or upgraded with networks of infrared and visible video cameras processing. The first technical specifications concerning sensor perfor- mance planned for the ITER VIS

  9. Layered Wyner-Ziv video coding: a new approach to video compression and delivery

    E-Print Network [OSTI]

    Xu, Qian

    2009-05-15T23:59:59.000Z

    Following recent theoretical works on successive Wyner-Ziv coding, we propose a practical layered Wyner-Ziv video coder using the DCT, nested scalar quantiza- tion, and irregular LDPC code based Slepian-Wolf coding (or lossless source coding...

  10. An Inclusive View of Player Modeling Adam M. Smith, Chris Lewis, Kenneth Hullett, Gillian Smith, Anne Sullivan

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    An Inclusive View of Player Modeling Adam M. Smith, Chris Lewis, Kenneth Hullett, Gillian Smith, Anne Sullivan Center for Games and Playable Media, UC Santa Cruz Santa Cruz, CA 95064, USA {amsmith

  11. Economic and environmental benefits of reducing standby power loss in DVD/VCD players and copiers in China

    E-Print Network [OSTI]

    Lin, Jiang; Li, Tienan; Li, Aizhen; Zhang, Guoqing

    2004-01-01T23:59:59.000Z

    Turns into a Flood: Standby Power Loss in China, Sinosphere,of Reducing Standby Power Loss in DVD/VCD Players ands awareness of standby power loss. Reducing standby power

  12. Pricing-based decentralized rate allocation for multiple video streams

    E-Print Network [OSTI]

    Tiwari, M; Groves, T; Cosman, P

    2009-01-01T23:59:59.000Z

    PRICE REM_PRICE PRE_PRICE (a) g8 video stream kbits per TS (video to 0.8-1.0 dB for the g8 video compared to EQL TS. ALLfor g11 to 0.9-1.1 dB for g8 compared to EQL TS. REM PRICE

  13. Interactive Montages of Sprites for Indexing and Summarizing Security Video

    E-Print Network [OSTI]

    Pal, Chris

    for indexing and visualizing video in the context of security applications. We wish to index security video that contains relatively rare but important events, such as security video taken from large public or industrial slowly occurring lighting changes and alterations of camera position. To achieve this, we compute a MAP

  14. CT Poison Control Center 2014 Video Contest Rules

    E-Print Network [OSTI]

    Kim, Duck O.

    CT Poison Control Center 2014 Video Contest Rules To Enter: 1) Record and upload a video to your an immediate family member who is an employee of the Connecticut Poison Control Center. Video Requirements: · DO NOT HANDLE, INGEST OR USE ANY ACTUAL POISONOUS OR HAZARDOUSSUBSTANCES. IF YOU HAVE QUESTIONS ABOUT

  15. Traffic-Aware Video Streaming in Broadband Wireless Networks

    E-Print Network [OSTI]

    Ansari, Nirwan

    Traffic-Aware Video Streaming in Broadband Wireless Networks Ehsan Haghani and Nirwan Ansari Shyam in the Internet. Streaming real-time video in wireless networks is a challenging problem due to the stringent video quality at the end user in wireless networks. Our solution incorporates the characteristics

  16. Strategies for three-dimensional particle tracking with holographic video

    E-Print Network [OSTI]

    Grier, David

    Strategies for three-dimensional particle tracking with holographic video microscopy Fook Chiong Research, New York University, New York, NY 10003 Abstract: The video stream captured by an in References and links 1. J. C. Crocker and D. G. Grier, "Methods of digital video microscopy for colloidal

  17. Strategies for threedimensional particle tracking with holographic video

    E-Print Network [OSTI]

    Grier, David

    Strategies for three­dimensional particle tracking with holographic video microscopy Fook Chiong Research, New York University, New York, NY 10003 Abstract: The video stream captured by an in References and links 1. J. C. Crocker and D. G. Grier, ``Methods of digital video microscopy for colloidal

  18. UITV 2005 Annual Report Executive Summary ITS VIDEO SERVICES

    E-Print Network [OSTI]

    UITV 2005 Annual Report Executive Summary ITS VIDEO SERVICES 1 Telecommunication and Network Services ITS Video Services 23 Lindquist Center 319-335-5898 UITV (University of Iowa Cable TelevisionBride, Video Services Program Manager INTRODUCTION 2005 could be called "The Year of the Student Producer

  19. UITV University of Iowa Cable Television ITS VIDEO SERVICES

    E-Print Network [OSTI]

    UITV ­ University of Iowa Cable Television ITS VIDEO SERVICES 1 UITV Telecommunication and Network Services ITS Video Services 23 Lindquist Center 319-335-5898 UITV, University of Iowa Cable Television Operations Report Calendar Year 2006 February 12, 2007 ­ Michael J. McBride, Video Services Program Manager

  20. DISS. ETH No. 18454 Full Body Modeling from Video Sequences

    E-Print Network [OSTI]

    Giger, Christine

    DISS. ETH No. 18454 Full Body Modeling from Video Sequences A dissertation submitted to the Swiss-camera calibration and investigates in the reconstruction, modeling and tracking of human body models from video useful combinations with useful results. The spatial and temporal character of the video se- quence

  1. UITV University of Iowa Cable Television ITS VIDEO SERVICES

    E-Print Network [OSTI]

    UITV ­ University of Iowa Cable Television ITS VIDEO SERVICES 1 UITV Report for Fiscal Year July 1 and Student Video Productions. o Programs are received from satellite programming services, like SCOLA foreign a venue for student programming, like Daily Iowan Television News and Student Video Productions. · On July

  2. Transmitting Digitized Video Using the Low Cost G-Link

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Transmitting Digitized Video Using the Low Cost G-Link Chipset Application Note 1077 h-Link) to distribute multiple uncompressed digitized video signals across a single coaxial or fiber-optic cable. Although the main theme of the paper is video distribution, the techniques discussed apply to any applica

  3. UITV 2004 Annual Report Executive Summary ITS VIDEO SERVICES

    E-Print Network [OSTI]

    UITV 2004 Annual Report Executive Summary ITS VIDEO SERVICES 1 Telecommunication and Network Services ITS Video Services 23 Lindquist Center 319-335-5898 UITV (University of Iowa Cable TelevisionBride, Video Services Program Manager UITV, University of Iowa Cable Television, is the cable television

  4. Robotic Exploration: Video Survey of the USS Macon Crash Site

    E-Print Network [OSTI]

    Prinz, Friedrich B.

    Robotic Exploration: Video Survey of the USS Macon Crash Site Stanford Aerospace Robotics Lab Prof of MBARI Photo courtesy of Naval Archives #12;2006 Goal: Video Survey Image courtesy of MBARI #12;Issue;User Interface #12;Control System Implementation PC ROV Control ROV + + Pilot joystick commands Video

  5. SUMMON@MU---Intro Video MU Libraries 1

    E-Print Network [OSTI]

    Taylor, Jerry

    SUMMON@MU---Intro Video MU Libraries 1 This is a brief introduction to Summon@MU, the newest way options are also available. #12;SUMMON@MU---Intro Video MU Libraries 2 After running a search... you can... #12;SUMMON@MU---Intro Video MU Libraries 3 And you can also limit your items to those with full text

  6. Augmented Reality for Later Playback of Videos Project Proposal

    E-Print Network [OSTI]

    Miles, Will

    1 Augmented Reality for Later Playback of Videos Project Proposal Jordan Stratton a video they have taken in order to easily find information about places they have been. We propose a method of allowing the user to take a video and choose whether or not to have augmented reality on while

  7. Video Stream Transmodality Pierre-Olivier Rocher12

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Video Stream Transmodality Pierre-Olivier Rocher12 , Christophe Gravier1 , Julien Subercaze12-olivier.rocher, christophe.gravier, julien.subercaze}@telecom-st-etienne.fr marius.preda@telecom-sudparis.eu Keywords: video, at constant bandwidth. In this paper we present the transmodality of video stream. Our contribution

  8. Indexing and Keyword Search to Ease Navigation in Lecture Videos

    E-Print Network [OSTI]

    Subhlok, Jaspal

    Indexing and Keyword Search to Ease Navigation in Lecture Videos Tayfun Tuna, Jaspal Subhlok@uh.edu, shah@cs.uh.edu Abstract----Lecture videos have been commonly used to supplement in-class teaching and for distance learning. Videos recorded during in-class teaching and made accessible online are a versatile

  9. Continuous Content-Based Copy Detection over Streaming Videos

    E-Print Network [OSTI]

    Ooi, Beng Chin

    Continuous Content-Based Copy Detection over Streaming Videos Ying Yan 1 , Beng Chin Ooi 2 , Aoying Computing, East China Normal University ayzhou@sei.ecnu.edu.cn Abstract-- Digital videos are increasingly adopted in various multimedia applications where they are usually broadcasted or transmitted as video

  10. Accurate Visual Features for Automatic Tag Correction in Videos

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Accurate Visual Features for Automatic Tag Correction in Videos Hoang-Tung Tran, Elisa Fromont-Etienne, Fr Abstract. We present a new system for video auto tagging which aims at correcting the tags provided by users for videos uploaded on the In- ternet. Unlike most existing systems, in our proposal, we

  11. Robust video denoising using low rank matrix completion , Chaoqiang Liu

    E-Print Network [OSTI]

    Shen, Zuowei

    Robust video denoising using low rank matrix completion Hui Ji , Chaoqiang Liu , Zuowei Shen video denoising algorithms assume a sin- gle statistical model of image noise, e.g. additive Gaussian white noise, which often is violated in practice. In this pa- per, we present a new patch-based video

  12. The effects of X-ray photoionization and heating on the structure of circumstellar discs

    E-Print Network [OSTI]

    R. D. Alexander; C. J. Clarke; J. E. Pringle

    2004-06-29T23:59:59.000Z

    We present the results of a theoretical study investigating the effects of photoionization and heating by X-rays on discs around low-mass stars. In particular we address the question of whether or not X-rays can drive a disc wind. First, we construct a 1-dimensional ``quasi-hydrostatic'' model, which solves for the vertical structure introduced by X-ray heating. We consider uniform X-ray illumination of the disc, but the X-ray fluxes required to heat the disc significantly are much greater than those seen by recent observations. When the model is extended to consider heating from a central X-ray source we find that the 1-dimensional model is only valid very close to the star. We extend our analysis to consider a simple 2-dimensional model, treating the disc as a two-layered structure and solving for its density profile self-consistently. For T Tauri stars we are able to set a crude upper limit on the mass-loss rate that can be driven by X-ray photoevaporation, with a value of ~10^-13 g/cm^2/s. Our model is designed to maximise this value, and most likely over-estimates it significantly. However we still find a mass-loss rate which is less than that found in studies of ultraviolet photoevaporation. We conclude that in the presence of a significant UV field, X-ray driven disc winds are unlikely to play a significant role in the evolution of discs around low-mass stars.

  13. Evolution of binary black holes in self gravitating discs: dissecting the torques

    E-Print Network [OSTI]

    Constanze Roedig; Alberto Sesana; Massimo Dotti; Jorge Cuadra; Pau Amaro-Seoane; Francesco Haardt

    2012-08-14T23:59:59.000Z

    We study the interplay between gas accretion and gravity torques in changing a binary elements and its total angular momentum (L) budget. Especially, we analyse the physical origin of the gravity torques (T_g) and their location within the disc. We analyse 3D SPH simulations of the evolution of initially quasi-circular massive black hole binaries (BHBs) residing in the central hollow of massive self-gravitating circumbinary discs. We use different thermodynamics within the cavity and for the numerical size of the black holes to show that (i) the BHB eccentricity growth found previously is a general result, independent of the accretion and the adopted thermodynamics; (ii) the semi-major axis decay depends both on the T_g and on the interplay with the disc-binary L-transfer due to accretion; (iii) the spectral structure of the T_g is predominately caused by disc edge overdensities and spiral arms developing in the body of the disc and, in general, does not reflect directly the period of the binary; (iv) the net T_g changes sign across the BHB corotation radius. We quantify the relative importance of the two, which appear to depend on the thermodynamical properties of the instreaming gas, and which is crucial in assessing the disc-binary L-transfer; (v) the net torque manifests as a purely kinematic (non-resonant) effect as it stems from the cavity, where the material flows in and out in highly eccentric orbits. Both accretion onto the black holes and the interaction with gas streams inside the cavity must be taken into account to assess the fate of the BHB. Moreover, the total torque exerted by the disc affects L(BHB) by changing all the elements (mass, mass ratio, eccentricity, semimajor axis) of the BHB. Common prescriptions equating tidal torque to semi-major axis shrinking might therefore be poor approximations for real astrophysical systems.

  14. VIDEO FINGERPRINTING BASED ON CENTROIDS OF GRADIENT ORIENTATIONS Sunil Lee and Chang D. Yoo

    E-Print Network [OSTI]

    Yoo, Chang D.

    VIDEO FINGERPRINTING BASED ON CENTROIDS OF GRADIENT ORIENTATIONS Sunil Lee and Chang D. Yoo Dept the video signal. The goal of a video fingerprinting sys- tem is to judge whether two videos have the same contents by measuring distance between fingerprints extracted from the videos. In this paper, a novel video

  15. Video Operations in the Gradient Domain Fusion of image sequences is a fundamental operation in numerous video applications and usually

    E-Print Network [OSTI]

    Cohen-Or, Daniel

    1 Video Operations in the Gradient Domain Abstract Fusion of image sequences is a fundamental operation in numerous video applications and usually consists of segmentation, matting and compositing. We present a unified framework for performing these operations on video in the gradient domain. Our approach

  16. Sloshing on London Eye: videos data --April 15, 2010--

    E-Print Network [OSTI]

    Bridges, Tom

    Sloshing on London Eye: videos data -- April 15, 2010-- 1 Video 1 The input data for the video 1 = Ct + 0 . The initial conditions are u (x, 0) = 0 , h (x, 0) = h0 . (1.3) 2 Video 2 The input data for the video 2 are: L = 1.0 m, r = 1.2 m, h0 = 0.17 m, x = 0.01 m, t = 0.01 sec, 1 4.057 rad/sec, r = 0.0 , d1

  17. Accretion Disc Turbulence and the X-Ray Power Spectra of Black Hole High States

    E-Print Network [OSTI]

    Michael A. Nowak; Robert V. Wagoner

    1994-10-06T23:59:59.000Z

    The high state of black hole candidates is characterized by a quasi- thermal emission component at $kT \\sim 1$ keV. In addition, this state tends to have very low variability which indicates that it is relatively stable, at least on {\\it short} time scales. Most models of the high state imply that the bulk of the emission comes from an optically thick accretion disc; therefore, this state may be an excellent laboratory for testing our ideas about the physics of accretion discs. In this work we consider the implications of assuming that accretion disc viscosity arises from some form of turbulence. Specifically, we consider the simple case of three dimensional hydrodynamic turbulence. It is found that the coupling of such turbulence to acoustic modes in the disc can alter the disc emission. We calculate the amplitude and frequencies of this modulation, and we express our results in terms of the X-ray power spectral density. We compare our calculations with observations of the black hole candidate GS 1124-683, and show that for certain parameters we can reproduce some of the high frequency power. We then briefly explore mechanisms for producing the low frequency power, and note the difficulty that a single variability mechanism has in reproducing the full range of observed variability. In addition, we outline ways in which future spacecraft missions -- such as USA and XTE -- can further constrain our model, especially at frequencies above $\\sim 10^2$ Hz.

  18. On the migration of two planets in a disc and the formation of mean motion resonances

    E-Print Network [OSTI]

    Migaszewski, Cezary

    2015-01-01T23:59:59.000Z

    We study the dynamics of a system of two super-Earths embedded in a protoplanetary disc. Depending on the disc parameters, planets' masses and positions in the disc, the migration of a planet can be inward or outward and the migration of a two-planet system can be convergent or divergent. The convergent migration means that the period ratio P2/P1 decreases in time. In such a case mean motion resonance (MMR) can be formed when the period ratio reaches a resonant value of a first order MMR (p+1)/p, where p is a small integer. When the divergent migration occurs, P2/P1 increases in time and a system initially close to MMR moves away from the resonance. We build a simple model of an irradiated viscous disc and use analytical prescriptions for the planet-disc interactions. We performed 3500 simulations of the migration of two-planet systems with various masses and initial orbits. We found that approximately half of the systems end up as configurations involved in one of the first order MMRs such as 2:1, 3:2, 4:3 a...

  19. The evolution of disc galaxies with and without classical bulges since z~1

    E-Print Network [OSTI]

    Sachdeva, Sonali; Saha, Kanak; Singh, Harinder P

    2015-01-01T23:59:59.000Z

    Establishing the relative role of internally and externally driven mechanisms responsible for disc and bulge growth is essential to understand the evolution of disc galaxies. In this context, we have studied the physical properties of disc galaxies without classical bulges in comparison to those with classical bulges since z~0.9. Using images from the Hubble Space Telescope and Sloan Digital Sky Survey, we have computed both parametric and non-parametric measures, and examined the evolution in size, concentration, stellar mass, effective stellar mass density and asymmetry. We find that both disc galaxies with and without classical bulges have gained more than 50% of their present stellar mass over the last ~8 Gyrs. Also, the increase in disc size is found to be peripheral. While the average total (Petrosian) radius almost doubles from z~0.9 to z~0, the average effective radius undergoes a marginal increase in comparison. Additionally, increase in the density of the inner region is evident through the evolutio...

  20. 2012 ARPA-E Energy Innovation Summit: Profiling City University of New York (CUNY): Reinventing Batteries for Grid Storage (Performer Video)

    ScienceCinema (OSTI)

    None Available

    2012-03-21T23:59:59.000Z

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. A few videos were selected for showing during the Summit to attendees. These 'performer videos' highlight innovative research that is ongoing and related to the main topics of the Summit's sessions. Featured in this video are Sanjoy Banerjee, Director of CUNY Energy Institute and Dan Steingart (Assistant Professor of Chemical Engineering, CUNY). The City University of New York's Energy Institute, with the help of ARPA-E funding, is creating safe, low cost, rechargeable, long lifecycle batteries that could be used as modular distributed storage for the electrical grid. The batteries could be used at the building level or the utility level to offer benefits such as capture of renewable energy, peak shaving and microgridding, for a safer, cheaper, and more secure electrical grid.

  1. 2012 ARPA-E Energy Innovation Summit: Profiling City University of New York (CUNY): Reinventing Batteries for Grid Storage (Performer Video)

    SciTech Connect (OSTI)

    None Available

    2012-02-28T23:59:59.000Z

    The third annual ARPA-E Energy Innovation Summit was held in Washington D.C. in February, 2012. The event brought together key players from across the energy ecosystem - researchers, entrepreneurs, investors, corporate executives, and government officials - to share ideas for developing and deploying the next generation of energy technologies. A few videos were selected for showing during the Summit to attendees. These 'performer videos' highlight innovative research that is ongoing and related to the main topics of the Summit's sessions. Featured in this video are Sanjoy Banerjee, Director of CUNY Energy Institute and Dan Steingart (Assistant Professor of Chemical Engineering, CUNY). The City University of New York's Energy Institute, with the help of ARPA-E funding, is creating safe, low cost, rechargeable, long lifecycle batteries that could be used as modular distributed storage for the electrical grid. The batteries could be used at the building level or the utility level to offer benefits such as capture of renewable energy, peak shaving and microgridding, for a safer, cheaper, and more secure electrical grid.

  2. Magnetic Turbulence and Thermodynamics in the Inner Region of Protoplanetary Discs

    E-Print Network [OSTI]

    Hirose, Shigenobu

    2015-01-01T23:59:59.000Z

    Using radiation magnetohydrodynamics simulations with realistic opacities and equation of state, and zero net magnetic flux, we have explored thermodynamics in the inner part of protoplanetary discs where magnetic turbulence is expected. The thermal equilibrium curve consists of the upper, lower, and middle branches. The upper (lower) branch corresponds to hot (cool) and optically very (moderately) thick discs, respectively, while the middle branch is characterized by convective energy transport near the midplane. Convection is also the major energy transport process near the low surface density end of the upper branch. There, convective motion is fast with Mach numbers reaching $\\gtrsim 0.01$, and enhances both magnetic turbulence and cooling, raising the ratio of vertically-integrated shear stress to vertically-integrated pressure by a factor of several. This convectively enhanced ratio seems a robust feature in accretion discs having an ionization transition. We have also examined causes of the S-shaped th...

  3. On the black hole limit of rotating discs of charged dust

    E-Print Network [OSTI]

    Martin Breithaupt; Yu-Chun Liu; Reinhard Meinel; Stefan Palenta

    2015-05-04T23:59:59.000Z

    Investigating the rigidly rotating disc of dust with constant specific charge, we find that it leads to an extreme Kerr-Newman black hole in the ultra-relativistic limit. A necessary and sufficient condition for a black hole limit is, that the electric potential in the co-rotating frame is constant on the disc. In that case certain other relations follow. These relations are reviewed with a highly accurate post-Newtonian expansion. Remarkably it is possible to survey the leading order behaviour close to the black hole limit with the post-Newtonian expansion. We find that the disc solution close to that limit can be approximated very well by a "hyper\\-extreme" Kerr-Newman solution with the same gravitational mass, angular momentum and charge.

  4. CMS Videos & Magnet M1 Website

    E-Print Network [OSTI]

    Almakhrazi, Majed Ahmed

    2014-01-01T23:59:59.000Z

    Doing 8 weeks internship in CERN gave me the opportunity to learn new skills and experiences. CERN is an organization where they operate the world's largest particle physics laboratory. Working on projects as a student is important to prepare for the work after the graduation. In this report, I will discuss the projects that I was assigned to, which are website upgrading, sketching drawings, and video editing, and present the results and compare them with the old ones.

  5. The structure and radiation spectra of illuminated accretion discs in AGN. I. Moderate illumination

    E-Print Network [OSTI]

    A. Ró?a?ska; A. -M. Dumont; B. Czerny; S. Collin

    2002-02-12T23:59:59.000Z

    We present detailed computations of the vertical structure of an accretion disc illuminated by hard X-ray radiation with the code {\\sc titan-noar} suitable for Compton thick media. The energy generated via accretion is dissipated partially in the cold disc as well as in the X-ray source. We study the differences between the case where the X-ray source is in the form of a lamp post above the accretion disc and the case of a heavy corona. We consider radiative heating via Comptonization together with heating via photo-absorption on numerous heavy elements as carbon, oxygen, silicon, iron. The transfer in lines is precisely calculated. A better description of the heating/cooling through the inclusion of line transfer, a correct description of the temperature in the deeper layers, a correct description of the entire disc vertical structure, as well as the study of the possible coronal pressure effect, constitute an improvement in comparison to previous works. We show that exact calculations of hydrostatic equilibrium and determination of the disc thickness has a crucial impact on the optical depth of the hot illuminated zone. We assume a moderate illumination where the viscous flux equals the X-ray radiation flux. A highly ionized skin is created in the lamp post model, with the outgoing spectrum containing many emission lines and ionization edges in emission or absorption in the soft X-ray domain, as well as an iron line at $\\sim 7 $ keV consisting of a blend of low ionization line from the deepest layers and hydrogen and helium like resonance line from the upper layers, and almost no absorption edge, contrary to the case of a slab of constant density.A full heavy corona completely suppresses the highly ionized zone on the top of the accretion disc and in such case the spectrum is featureless.

  6. W.C. Heraeus GmbH and its activities regarding large grain Niobium Discs

    SciTech Connect (OSTI)

    Spaniol, Bernd [W.C.Heraeus GmbH, Engineered Material Division, Heraeusstrasse 12-14, 63450 Hanau (Germany)

    2007-08-09T23:59:59.000Z

    W.C. Heraeus is one of the leading companies in the field of precious and refractory metals. The refractory metals activities have been started in 1940. W.C. Heraeus is one of the qualified suppliers for high pure Niobium for the use in high-frequency-super-conducting cavities. The latest activities in that field are the development of a stable Electron-Beam-Melting and reliable cutting processes to produce large grain Niobium discs directly cut from the Ingot in an industrial scale. The first cavities out of these discs have been tested and are showing excellent magnetic properties.

  7. The Gaia-ESO Survey: a quiescent Milky Way with no significant dark/stellar accreted disc

    E-Print Network [OSTI]

    Ruchti, G R; Feltzing, S; Serenelli, A M; McMillan, P; Lind, K; Bensby, T; Bergemann, M; Asplund, M; Vallenari, A; Flaccomio, E; Pancino, E; Korn, A J; Recio-Blanco, A; Bayo, A; Carraro, G; Costado, M T; Damiani, F; Heiter, U; Hourihane, A; Jofre, P; Kordopatis, G; Lardo, C; de Laverny, P; Monaco, L; Morbidelli, L; Sbordone, L; Worley, C C; Zaggia, S

    2015-01-01T23:59:59.000Z

    According to our current cosmological model, galaxies like the Milky Way are expected to experience many mergers over their lifetimes. The most massive of the merging galaxies will be dragged towards the disc-plane, depositing stars and dark matter into an accreted disc structure. In this work, we utilize the chemo-dynamical template developed in Ruchti et al. to hunt for accreted stars. We apply the template to a sample of 4,675 stars in the third internal data release from the Gaia-ESO Spectroscopic Survey. We find a significant component of accreted halo stars, but find no evidence of an accreted disc component. This suggests that the Milky Way has had a rather quiescent merger history since its disc formed some 8-10 billion years ago and therefore possesses no significant dark matter disc.

  8. Using Photogrammetry to Estimate Tank Waste Volumes from Video

    SciTech Connect (OSTI)

    Field, Jim G. [Washington River Protection Solutions, LLC, Richland, WA (United States)

    2013-03-27T23:59:59.000Z

    Washington River Protection Solutions (WRPS) contracted with HiLine Engineering & Fabrication, Inc. to assess the accuracy of photogrammetry tools as compared to video Camera/CAD Modeling System (CCMS) estimates. This test report documents the results of using photogrammetry to estimate the volume of waste in tank 241-C-I04 from post-retrieval videos and results using photogrammetry to estimate the volume of waste piles in the CCMS test video.

  9. Energetics of star-disc encounters in the non-linear regime

    E-Print Network [OSTI]

    S. M. Hall; C. J. Clarke; J. E. Pringle

    1995-10-31T23:59:59.000Z

    We investigate the response of a circumstellar accretion disc to the fly-by of a perturbing mass on a parabolic orbit. The energy and angular momentum transferred during the encounter are calculated using a reduced three-body method. In almost all close encounters the energy and angular momentum transfer is dominated by disc material becoming unbound from the system, with the contributions from close disc particle -- star encounters being significant. For more distant encounters with some prograde element to the motion the disc material loses energy and angular momentum to the perturber's orbit through a resonance feature. The magnitude of the energy transfer calculated in our simulations is greater than that of the binding energy of material exterior to periastron by a factor of two in the prograde case, and up to a factor of five in the case of the retrograde encounter. The destructive nature of the encounters indicates that a non-linear treatment is essential in all but the most distant encounters.

  10. Anisotropic radiation from accretion disc-coronae in active galactic nuclei

    E-Print Network [OSTI]

    Xu, Ya-Di

    2015-01-01T23:59:59.000Z

    In the unification scheme of active galactic nuclei (AGN), Seyfert 1s and Seyfert 2s are intrinsically same, but they are viewed at different angles. However, the Fe K\\alpha emission line luminosity of Seyfert 1s was found in average to be about twice of that of Seyfert 2s at given X-ray continuum luminosity in the previous work (Ricci et al. 2014). We construct an accretion disc-corona model, in which a fraction of energy dissipated in the disc is extracted to heat the corona above the disc. The radiation transfer equation containing Compton scattering processes is an integro-differential equation, which is solved numerically for the corona with a parallel plane geometry. We find that the specific intensity of X-ray radiation from the corona changes little with the viewing angle \\theta when \\theta is small (nearly face-on), and it is sensitive to \\theta if the viewing angle is large (\\theta> 40 degrees). The radiation from the cold disc, mostly in infrared/optical/UV bands, is almost proportional to cos\\thet...

  11. Internal Alignments of Red Versus Blue Discs in Dark Matter Halos

    E-Print Network [OSTI]

    Debattista, Victor P; Roskar, Rok; Quinn, Thomas; Moore, Ben; Cole, David R

    2015-01-01T23:59:59.000Z

    Large surveys have shown that red galaxies are preferentially aligned with their halos while blue galaxies have a more isotropic distribution. Since halos generally align with their filaments this introduces a bias in the measurement of the cosmic shear from weak lensing. It is therefore vitally important to understand why this difference arises. We explore the stability of different disc orientations within triaxial halos. We show that, in the absence of gas, the disc orientation is most stable when its spin is along the minor axis of the halo. Instead when gas cools onto a disc it is able to form in almost arbitrary orientation, including off the main planes of the halo (but avoiding an orientation perpendicular to the halo's intermediate axis). Substructure helps gasless galaxies reach alignment with the halo faster, but have less effect on galaxies when gas is cooling onto the disc. Our results provide a novel and natural interpretation for why red, gas poor galaxies are preferentially aligned with their ...

  12. The local star formation history of the thin disc derived from kinematic data

    E-Print Network [OSTI]

    A. Just; H. Jahreiss

    2010-12-27T23:59:59.000Z

    We present an evolutionary disc model for the thin disc in the solar cylinder based on a continuous star formation history and a continuous dynamical heating of the stellar subpopulations. The vertical distribution of the stellar subpopulations are calculated self-consistently in dynamical equilibrium. The SFR and AVR of the stellar subpopulations are determined by fitting the velocity distribution functions of main sequence stars. The SFR shows a maximum 10 Gyr ago declining by a factor of 10 until present time. A constant SFR can be ruled out. The velocity dispersion of the stellar subpopulations increase with age according to a power law with index 0.375. The new scale heights lead to a best fit IMF with power-law indices of 1.5 below and 4.0 above 1.6 Msun, which has no kink around 1 Msun. Including a thick disc component results in slight variations of the thin disc properties, but has a negligible influence on the SFR. A variety of predictions are made concerning the number density, age and metallicity distributions of stellar subpopulations as a function of z above the galactic plane.

  13. Searching for signatures of planet formation in stars with circumstellar debris discs

    E-Print Network [OSTI]

    Maldonado, J; Villaver, E; Montesinos, B; Mora, A

    2015-01-01T23:59:59.000Z

    (Abridged) Tentative correlations between the presence of dusty debris discs and low-mass planets have been presented. In parallel, detailed chemical abundance studies have reported different trends between samples of planet and non-planet hosts. We determine in a homogeneous way the metallicity, and abundances of a sample of 251 stars including stars with known debris discs, with debris discs and planets, and only with planets. Stars with debris discs and planets have the same [Fe/H] behaviour as stars hosting planets, and they also show a similar -Tc trend. Different behaviour in the -Tc trend is found between the samples of stars without planets and the samples of planet hosts. In particular, when considering only refractory elements, negative slopes are shown in cool giant planet hosts, whilst positive ones are shown in stars hosting low-mass planets. Stars hosting exclusively close-in giant planets show higher metallicities and positive -Tc slope. A search for correlations between the -Tc slopes and the ...

  14. The structure and radiation spectra of illuminated accretion discs in AGN. I. Moderate illumination

    E-Print Network [OSTI]

    Rózanska, A R; Czerny, B; Collin, S

    2002-01-01T23:59:59.000Z

    We present detailed computations of the vertical structure of an accretion disc illuminated by hard X-ray radiation with the code {\\sc titan-noar} suitable for Compton thick media. The energy generated via accretion is dissipated partially in the cold disc as well as in the X-ray source. We study the differences between the case where the X-ray source is in the form of a lamp post above the accretion disc and the case of a heavy corona. We consider radiative heating via Comptonization together with heating via photo-absorption on numerous heavy elements as carbon, oxygen, silicon, iron. The transfer in lines is precisely calculated. A better description of the heating/cooling through the inclusion of line transfer, a correct description of the temperature in the deeper layers, a correct description of the entire disc vertical structure, as well as the study of the possible coronal pressure effect, constitute an improvement in comparison to previous works. We show that exact calculations of hydrostatic equilib...

  15. Gathering data on allegations of sexual abuse made against former disc jockey, Jimmy Savile 

    E-Print Network [OSTI]

    Smith, Mark; Kirkwood, Steve; Llewellyn, Clare

    2014-08-26T23:59:59.000Z

    This paper will report on a collaboration between Social Work and Informatics academics and Library staff at the University. The focus of the work is to secure a data set on allegations of sexual abuse made against the former disc jockey, Jimmy...

  16. DiSC: Benchmarking Secure Chip DBMS Nicolas Anciaux, Luc Bouganim, Philippe Pucheral, and Patrick Valduriez

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    DiSC: Benchmarking Secure Chip DBMS Nicolas Anciaux, Luc Bouganim, Philippe Pucheral, and Patrick irrelevant. The main problem faced by secure chip DBMS designers is to be able to assess various design choices and trade-offs for different applications. Our solution is to use a benchmark for secure chip DBMS

  17. 2D-Zernike polynomials and coherent state quantization of the unit disc

    E-Print Network [OSTI]

    K. Thirulogasanthar; Nasser Saad; G. Honnouvo

    2015-01-07T23:59:59.000Z

    Using the orthonormality of the 2D-Zernike polynomials, reproducing kernels, reproducing kernel Hilbert spaces, and ensuring coherent states attained. With the aid of the so-obtained coherent states, the complex unit disc is quantized. Associated upper symbols, lower symbols and related generalized Berezin transforms also obtained. A number of necessary summation formulas for the 2D-Zernike polynomials proved.

  18. Resonant Trapping in the Galactic Disc and Halo and its Relation with Moving Groups

    E-Print Network [OSTI]

    Moreno, Edmundo; Schuster, William

    2015-01-01T23:59:59.000Z

    With the use of a detailed Milky Way nonaxisymmetric potential, observationally and dynamically constrained, the e?ects of the bar and the spiral arms in the Galaxy are studied in the disc and in the stellar halo. Especially the trapping of stars in the disc and Galactic halo by resonances on the Galactic plane, induced by the Galactic bar, has been analysed in detail. To this purpose, a new method is presented to delineate the trapping regions using empirical diagrams of some orbital properties obtained in the Galactic potential. In these diagrams we plot in the inertial Galactic frame a characteristic orbital energy versus a characteristic orbital angular momentum, or versus the orbital Jacobi constant in the reference frame of the bar, when this is the only nonaxisymmetric component in the Galactic potential. With these diagrams some trapping regions are obtained in the disc and halo using a sample of disc stars and halo stars in the solar neighbourhood. We compute several families of periodic orbits on th...

  19. Tidal disruptions in circumbinary discs (I): Star formation, dynamics, and binary evolution

    E-Print Network [OSTI]

    Pau Amaro-Seoane; Patrick Brem; Jorge Cuadra

    2012-12-11T23:59:59.000Z

    In our current interpretation of the hierarchical structure of the universe it is well established that galaxies collide and merge with each other during their lifetime. If massive black holes (MBHs) reside in galactic centres, we expect them to form binaries in galactic nuclei surrounded by a circumbinary disc. If cooling is efficient enough, the gas in the disc will clump and trigger stellar formation in situ. In this first paper we address the evolution of the binary under the influence of the newly formed stars, which form individually and also clustered. We use SPH techniques to evolve the gas in the circumbinary disc and to study the phase of star formation. When the amount of gas in the disc is negligible, we further evolve the system with a high-accurate direct-summation $N-$body code to follow the evolution of the stars, the innermost binary and tidal disruption events (TDEs). For this, we modify the direct N-body code to (i) include treatment of TDEs and to (ii) include "gas cloud particles" that mimic the gas, so that the stellar clusters do not disolve when we follow their infall on to the MBHs. We find that the amount of stars disrupted by either infalling stellar clusters or individual stars is as large as 10^{-4}/yr per binary, higher than expected for typical galaxies.

  20. Sedimenting discs in a two-dimensional foam I. T. Davies, S. J. Cox

    E-Print Network [OSTI]

    Cox, Simon

    -dimensional foams can be thought of as a monolayer of bubbles squeezed between two glass plates. We choose to probeSedimenting discs in a two-dimensional foam I. T. Davies, S. J. Cox Institute of Mathematics in a dry two-dimensional, monodisperse foam is studied. This, a variation of the classical Stokes