Sample records for high gradient collaboration

  1. High Gradient Inverse Free Electron Laser (IFEL) Accelerator

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

    Gradient High energy gain Inverse Free Electron Laser P. Musumeci UCLA Department of Physics and Astronomy On Behalf of the RUBICON collaboration ATF user meeting, BNL, October 6...

  2. HIGH GRADIENT INDUCTION ACCELERATOR

    SciTech Connect (OSTI)

    Caporaso, G J; Sampayan, S; Chen, Y; Blackfield, D; Harris, J; Hawkins, S; Holmes, C; Krogh, M; Nelson, S; Nunnally, W; Paul, A; Poole, B; Rhodes, M; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J

    2007-06-21T23:59:59.000Z

    A new type of compact induction accelerator is under development at the Lawrence Livermore National Laboratory that promises to increase the average accelerating gradient by at least an order of magnitude over that of existing induction machines. The machine is based on the use of high gradient vacuum insulators, advanced dielectric materials and switches and is stimulated by the desire for compact flash x-ray radiography sources. Research describing an extreme variant of this technology aimed at proton therapy for cancer will be described. Progress in applying this technology to several applications will be reviewed.

  3. High field gradient particle accelerator

    DOE Patents [OSTI]

    Nation, J.A.; Greenwald, S.

    1989-05-30T23:59:59.000Z

    A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications is disclosed. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle. 10 figs.

  4. High field gradient particle accelerator

    DOE Patents [OSTI]

    Nation, John A. (Ithaca, NY); Greenwald, Shlomo (Haifa, IL)

    1989-01-01T23:59:59.000Z

    A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle.

  5. High Gradient Two-Beam Electron Accelerator

    SciTech Connect (OSTI)

    Jiang, Y. [Beam Physics Laboratory, Yale University, 272 Whitney Ave., New Haven, CT 06511 (United States); Kazakov, S. Yu. [Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Kuzikov, S. V. [Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Institute of Applied Physics, Nizhny Novgorod, 603600 (Russian Federation); Hirshfield, J. L. [Beam Physics Laboratory, Yale University, 272 Whitney Ave., New Haven, CT 06511 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States)

    2010-11-04T23:59:59.000Z

    A high-gradient two-beam electron accelerator structure using detuned cavities is described. A self-consistent theory based on a circuit model is presented to calculate idealized acceleration gradient, transformer ratio, and efficiency for energy transfer from the drive beam to the accelerated beam. Experimental efforts are being carried out to demonstrate this acceleration concept.

  6. Developing new high energy gradient concentration cathode material...

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

    new high energy gradient concentration cathode material Developing new high energy gradient concentration cathode material 2009 DOE Hydrogen Program and Vehicle Technologies...

  7. High-pressure liquid chromatographic gradient mixer

    DOE Patents [OSTI]

    Daughton, C.G.; Sakaji, R.H.

    1982-09-08T23:59:59.000Z

    A gradient mixer effects the continuous mixing of any two miscible solvents without excessive decay or dispersion of the resultant isocratic effluent or of a linear or exponential gradient. The two solvents are fed under low or high pressure by means of two high performance liquid chromatographic pumps. The mixer comprises a series of ultra-low dead volume stainless steel tubes and low dead volume chambers. The two solvent streams impinge head-on at high fluxes. This initial nonhomogeneous mixture is then passed through a chamber packed with spirally-wound wires which cause turbulent mixing thereby homogenizing the mixture with minimum band-broadening.

  8. High pressure liquid chromatographic gradient mixer

    DOE Patents [OSTI]

    Daughton, Christian G. (San Pablo, CA); Sakaji, Richard H. (El Cerrito, CA)

    1985-01-01T23:59:59.000Z

    A gradient mixer which effects the continuous mixing of any two miscible solvents without excessive decay or dispersion of the resultant isocratic effluent or of a linear or exponential gradient. The two solvents are fed under low or high pressure by means of two high performance liquid chromatographic pumps. The mixer comprises a series of ultra-low dead volume stainless steel tubes and low dead volume chambers. The two solvent streams impinge head-on at high fluxes. This initial nonhomogeneous mixture is then passed through a chamber packed with spirally-wound wires which cause turbulent mixing thereby homogenizing the mixture with minimum "band-broadening".

  9. Exploration of very high gradient cavities

    SciTech Connect (OSTI)

    Grigory Eremeev

    2011-07-01T23:59:59.000Z

    Several of the 9-cell ILC cavities processed at Jlab within ongoing ILC R&D program have shown interesting behavior at high fields, such as mode mixing and sudden field emission turn-on during quench. Equipped with thermometry and oscillating superleak transducer (OST) system for quench detection, we couple our RF measurements with local dissipation measurements. In this contribution we report on our findings with high gradient SRF cavities.

  10. Ultra-High Gradient Compact S-Band Linac for Laboratory and Industrial Applications

    SciTech Connect (OSTI)

    Faillace, Luigi; /RadiaBeam Tech.; Agustsson, Ronald; /RadiaBeam Tech.; Frigola, Pedro; /RadiaBeam Tech.; Murokh, Alex; /RadiaBeam Tech.; Dolgashev, Valery; /SLAC; Rosenzweig, James; /UCLA

    2012-07-03T23:59:59.000Z

    There is growing demand from the industrial and research communities for high gradient, compact RF accelerating structures. The commonly used S-band SLAC-type structure has an operating gradient of only about 20 MV/m; while much higher operating gradients (up to 70 MV/m) have been recently achieved in X-band, as a consequence of the substantial efforts by the Next Linear Collider (NLC) collaboration to push the performance envelope of RF structures towards higher accelerating gradients. Currently however, high power X-band RF sources are not readily available for industrial applications. Therefore, RadiaBeam Technologies is developing a short, standing wave S-band structure which uses frequency scaled NLC design concepts to achieve up to a 50 MV/m operating gradient at 2856 MHz. The design and prototype commissioning plans are presented.

  11. High gradient lens for charged particle beam

    DOE Patents [OSTI]

    Chen, Yu-Jiuan

    2014-04-29T23:59:59.000Z

    Methods and devices enable shaping of a charged particle beam. A dynamically adjustable electric lens includes a series of alternating a series of alternating layers of insulators and conductors with a hollow center. The series of alternating layers when stacked together form a high gradient insulator (HGI) tube to allow propagation of the charged particle beam through the hollow center of the HGI tube. A plurality of transmission lines are connected to a plurality of sections of the HGI tube, and one or more voltage sources are provided to supply an adjustable voltage value to each transmission line of the plurality of transmission lines. By changing the voltage values supplied to each section of the HGI tube, any desired electric field can be established across the HGI tube. This way various functionalities including focusing, defocusing, acceleration, deceleration, intensity modulation and others can be effectuated on a time varying basis.

  12. High-gradient compact linear accelerator

    DOE Patents [OSTI]

    Carder, B.M.

    1998-05-26T23:59:59.000Z

    A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the dielectric core. All the field segments in the dielectric core are then in unipolar agreement until the slower wave finally propagates to the third dielectric core across the dielectric plates with the wider spacing and higher dielectric constant. During such unipolar agreement, particles in the core are accelerated with gradients that exceed twenty megavolts per meter. 10 figs.

  13. Development of High-Gradient Dielectric Laser-Driven Particle Accelerator Structures

    SciTech Connect (OSTI)

    Byer, Robert L.

    2013-11-07T23:59:59.000Z

    The thrust of Stanford's program is to conduct research on high-gradient dielectric accelerator structures driven with high repetition-rate, tabletop infrared lasers. The close collaboration between Stanford and SLAC (Stanford Linear Accelerator Center) is critical to the success of this project, because it provides a unique environment where prototype dielectric accelerator structures can be rapidly fabricated and tested with a relativistic electron beam.

  14. Microsoft PowerPoint - High Gradient Inverse Free Electron Laser...

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

    Hi h G di t Hi h i High Gradient High energy gain Inverse Free Electron Laser at BNL P. Musumeci UCLA Department of Physics and Astronomy ATF user meeting April 2-3 2009 Outline...

  15. HTS High Gradient Magnetic Separation system

    SciTech Connect (OSTI)

    Daugherty, M.A.; Coulter, J.Y.; Hults, W.L. [and others

    1996-09-01T23:59:59.000Z

    We report on the assembly, characterization and operation of a high temperature superconducting (HTS) magnetic separator. The magnet is made of 624 m of Silver/BSCCO superconducting wire and has overall dimensions of 18 cm OD, 15.5 cm height and 5 cm ID. The HTS current leads are designed to operate with the warm end at 75 K and the cold end cooled by a two stage Gifford-McMahon cryocooler. The upper stage of the cryocooler cools the thermal shield and two heat pipe thermal intercepts. The lower stage of the cryocooler cools the HTS magnet and the bottom end of the HTS current leads. The HTS magnet was initially characterized in liquid cryogens. We report on the current- voltage (I-V) characteristics of the HTS magnet at temperatures ranging from 15 to 40 K. At 40 K the magnet can generate a central field of 2.0 T at a current of 120 A.

  16. High and ulta-high gradient quadrupole magnets

    SciTech Connect (OSTI)

    Brunk, W.O.; Walz, D.R.

    1985-05-01T23:59:59.000Z

    Small bore conventional dc quadrupoles with apertures from 1 to 2.578cm were designed and prototypes built and measured. New fabrication techniques including the use of wire electric discharge milling (EDM) to economically generate the pole tip contours and aperture tolerances are described. Magnetic measurement data from a prototype of a 1cm aperture quadrupole with possible use in future e/sup +//e/sup -/ super colliders are presented. At a current of 400A, the lens achieved a gradient of 2.475 T/cm, and had an efficiency of 76.6%.

  17. Collaborative Estimation of Gradient Direction by a Formation of AUVs under Communication Constraints

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of Autonomous Underwater Vehicles (AUVs). The present paper proposes a distributed solution in which a group], and autonomous systems as underwater and unmanned air ve- hicles (AUVs and UAVs) [6], [7]. Cooperative formation of vehicles uniformly distributed in a fixed circular formation, estimates the gradient direction

  18. Fabrication of high gradient insulators by stack compression

    DOE Patents [OSTI]

    Harris, John Richardson; Sanders, Dave; Hawkins, Steven Anthony; Norona, Marcelo

    2014-04-29T23:59:59.000Z

    Individual layers of a high gradient insulator (HGI) are first pre-cut to their final dimensions. The pre-cut layers are then stacked to form an assembly that is subsequently pressed into an HGI unit with the desired dimension. The individual layers are stacked, and alignment is maintained, using a sacrificial alignment tube that is removed after the stack is hot pressed. The HGI's are used as high voltage vacuum insulators in energy storage and transmission structures or devices, e.g. in particle accelerators and pulsed power systems.

  19. Operational experience with CW high gradient and high QL cryomodules

    SciTech Connect (OSTI)

    Hovater, J. Curt [JLAB; Allison, Trent L. [JLAB; Bachimanchi, Ramakrishna [JLAB; Daly, Edward F. [JLAB; Drury, Michael A. [JLAB; Lahti, George E. [JLAB; Mounts, Clyde I. [JLAB; Nelson, Richard M. [JLAB; Plawski, Tomasz E. [JLAB

    2014-12-01T23:59:59.000Z

    The Continuous Electron Beam Accelerator Facility (CEBAF) energy upgrade from 6 GeV to 12 GeV includes the installation of ten new 100 MV cryomodules (80 cavities). The superconducting RF cavities are designed to operate CW at an accelerating gradient of 19.3 MV/m with a QL of 3×107. The RF system employs single cavity control using new digital LLRF controls and 13 kW klystrons. Recently, all of the new cryomodules and associated RF hardware and software have been commissioned and operated in the CEBAF accelerator. Electrons at linac currents up to 10 ?A have been successfully accelerated and used for nuclear physics experiments. This paper reports on the commissioning and operation of the cryomodules and RF system.

  20. SLIM, Short-pulse Technology for High Gradient Induction Accelerators

    SciTech Connect (OSTI)

    Arntz, Floyd; /Diversified Tech., Bedford; Kardo-Sysoev, A.; /Ioffe Phys. Tech. Inst.; Krasnykh, A.; /SLAC

    2008-12-16T23:59:59.000Z

    A novel short-pulse concept (SLIM) suited to a new generation of a high gradient induction particle accelerators is described herein. It applies advanced solid state semiconductor technology and modern microfabrication techniques to a coreless induction method of charged particle acceleration first proven on a macro scale in the 1960's. Because this approach avoids use of magnetic materials there is the prospect of such an accelerator working efficiently with accelerating pulses in the nanosecond range and, potentially, at megahertz pulse rates. The principal accelerator section is envisioned as a stack of coreless induction cells, the only active element within each being a single, extremely fast (subnanosecond) solid state opening switch: a Drift Step Recovery Diode (DSRD). Each coreless induction cell incorporates an electromagnetic pulse compressor in which inductive energy developed within a transmission-line feed structure over a period of tens of nanoseconds is diverted to the acceleration of the passing charge packet for a few nanoseconds by the abrupt opening of the DSRD switch. The duration of this accelerating output pulse--typically two-to-four nanoseconds--is precisely determined by a microfabricated pulse forming line connected to the cell. Because the accelerating pulse is only nanoseconds in duration, longitudinal accelerating gradients approaching 100 MeV per meter are believed to be achievable without inciting breakdown. Further benefits of this approach are that, (1) only a low voltage power supply is required to produce the high accelerating gradient, and, (2) since the DSRD switch is normally closed, voltage stress is limited to a few nanoseconds per period, hence the susceptibility to hostile environment conditions such as ionizing radiation, mismatch (e.g. in medical applications the peak beam current may be low), strong electromagnetic noise levels, etc is expected to be minimal. Finally, we observe the SLIM concept is not limited to linac applications; for instance, it could be employed to both accelerate the beam and to stabilize the superbunch mode of operation in circular track machines.

  1. Dielectric-Lined High-Gradient Accelerator Structure

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-04-24T23:59:59.000Z

    Rectangular particle accelerator structures with internal planar dielectric elements have been studied, with a view towards devising structures with lower surface fields for a given accelerating field, as compared with structures without dielectrics. Success with this concept is expected to allow operation at higher accelerating gradients than otherwise on account of reduced breakdown probabilities. The project involves studies of RF breakdown on amorphous dielectrics in test cavities that could enable high-gradient structures to be built for a future multi-TeV collider. The aim is to determine what the limits are for RF fields at the surfaces of selected dielectrics, and the resulting acceleration gradient that could be achieved in a working structure. The dielectric of principal interest in this study is artificial CVD diamond, on account of its advertised high breakdown field ({approx}2 GV/m for dc), low loss tangent, and high thermal conductivity. Experimental studies at mm-wavelengths on materials and structures for achieving high acceleration gradient were based on the availability of the 34.3 GHz third-harmonic magnicon amplifier developed by Omega-P, and installed at the Yale University Beam Physics Laboratory. Peak power from the magnicon was measured to be about 20 MW in 0.5 {micro}s pulses, with a gain of 54 dB. Experiments for studying RF high-field effects on CVD diamond samples failed to show any evidence after more than 10{sup 5} RF pulses of RF breakdown up to a tangential surface field strength of 153 MV/m; studies at higher fields were not possible due to a degradation in magnicon performance. A rebuild of the tube is underway at this writing. Computed performance for a dielectric-loaded rectangular accelerator structure (DLA) shows highly competitive properties, as compared with an existing all-metal structure. For example, comparisons were made of a DLA structure having two planar CVD diamond elements with a all-metal CERN structure HDS operating at 30 GHz. It was shown that the ratio of maximum surface electric field to accelerating field at the metal wall is only 0.35-0.4 for DLA, much smaller than the value 2.2 for HDS; and the ratio of surface magnetic field to accelerating field is 3.0 mA/V for DLA, compared with 3.45 mA/V for HDS. These values bode well for DLA in helping to avoid breakdown and to reducing pulsed surface heating and fatigue. The shunt impedance is found to be 160-175 M{Omega}/m for DLA, as compared to 99 M{Omega}/m for HDS. Conclusions are reached from this project that CVD diamond appears promising as a dielectric with a high threshold for RF breakdown, and that rectangular accelerator structures can be devised using planar CVD diamond elements that could be operated at higher acceleration gradients with low probability of RF breakdown, as compared with corresponding all-metallic structures.

  2. SLIM, Short-pulse Technology for High Gradient Induction Accelerators

    SciTech Connect (OSTI)

    Krasnykh, A.; /SLAC; Kardo-Sysoev, A.; /Ioffe Phys. Tech. Inst.; Arntz, F.; /Diversified Tech., Bedford

    2009-12-09T23:59:59.000Z

    The conclusions of this paper are: (1) The gradient of the SLIM-based technology is believed to be achievable in the same range as it is for the gradient of a modern rf-linac technology ({approx}100 MeV per meter). (2) The SLIM concept is based on the nsec TEM pulse mode operation with no laser or rf systems. (3) Main components of SLIM are not stressed while the energy is pumped into the induction system. Components can accept the hard environment conditions such as a radiation dose, mismatch, hard electromagnetic nose level, etc. Only for several nanoseconds the switch is OFF and produces a stress in the induction system. At that time, the delivery of energy to the beam takes place. (4) The energy in the induction system initially is storied in the magnetic field when the switch is ON. That fact makes another benefit: a low voltage power supplies can be used. The reliability of a lower voltage power supply is higher and they are cheaper. (5) The coreless SLIM concept offers to work in the MHz range of repetition rate. The induction system has the high electric efficiency (much higher than the DWA). (6) The array of lined up and activated SLIM cells is believed to be a solid state structure of novel accelerating technology. The electron-hole plasma in the high power solid state structure is precisely controlled by the electromagnetic process of a pulsed power supply.

  3. Analysis Code for High Gradient Dielectric Insulator Surface Breakdown

    SciTech Connect (OSTI)

    Ives, Robert Lawrence [Calabazas Creek Research, Inc.; Verboncoeur, John [University of California - Berkeley; Aldan, Manuel [University of California, Berkeley

    2010-05-30T23:59:59.000Z

    High voltage (HV) insulators are critical components in high-energy, accelerator and pulsed power systems that drive diverse applications in the national security, nuclear weapons science, defense and industrial arenas. In these systems, the insulator may separate vacuum/non-vacuum regions or conductors with high electrical field gradients. These insulators will often fail at electric fields over an order of magnitude lower than their intrinsic dielectric strength due to flashover at the dielectric interface. Decades of studies have produced a wealth of information on fundamental processes and mechanisms important for flashover initiation, but only for relatively simple insulator configurations in controlled environments. Accelerator and pulsed power system designers are faced with applying the fundamental knowledge to complex, operational devices with escalating HV requirements. Designers are forced to rely on “best practices” and expensive prototype testing, providing boundaries for successful operation. However, the safety margin is difficult to estimate, and system design must be very conservative for situations where testing is not practicable, or replacement of failed parts is disruptive or expensive. The Phase I program demonstrated the feasibility of developing an advanced code for modeling insulator breakdown. Such a code would be of great interest for a number of applications, including high energy physics, microwave source development, fusion sciences, and other research and industrial applications using high voltage devices.

  4. Modified Magnicon for High-Gradient Accelerator R&D

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2011-12-19T23:59:59.000Z

    Analysis, and low-power cold tests are described on a modified design intended for the Ka-band pulsed magnicon now in use for high-gradient accelerator R and D and rare elementary particle searches at the Yale University Beam Physics Laboratory. The modification is mainly to the output cavity of the magnicon, which presently operates in the TM310 mode. It is proposed to substitute for this a dual-chamber TE311 cavity structure. The first chamber is to extract about 40% of the beam power (about 25 MW) at 34.272 GHz, while the second chamber is to convey the power to four WR-28 output waveguides. Minor design changes are also proposed for the penultimate 11.424 GHz cavity and the beam collector. The intention of these design changes is to allow the magnicon to operate reliably 24/7, with minor sensitivity to operating parameters.

  5. Gearbox Reliability Collaborative High-Speed Shaft Calibration

    SciTech Connect (OSTI)

    Keller, J.; McNiff, B.

    2014-09-01T23:59:59.000Z

    Instrumentation has been added to the high-speed shaft, pinion, and tapered roller bearing pair of the Gearbox Reliability Collaborative gearbox to measure loads and temperatures. The new shaft bending moment and torque instrumentation was calibrated and the purpose of this document is to describe this calibration process and results, such that the raw shaft bending and torque signals can be converted to the proper engineering units and coordinate system reference for comparison to design loads and simulation model predictions.

  6. A HIGH GRADIENT QUADRUPOLE MAGNET FOR THE SSC

    E-Print Network [OSTI]

    Taylor, C.

    2010-01-01T23:59:59.000Z

    on gradient and qu;;lity, if the buss grooves are located atto accommodate the m;;! in current buss, the lowp.r ']roovewIring and corrector buss, and thp. symmetrically-placed

  7. Collaboration

    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 Office511041clothAdvanced Materials Advanced. C o w l i t zManufacturing:DOECoachIndustrialCollaboration

  8. The Neutrino Factory and Muon Collider Collaboration High-Power Targets and Particle Collection

    E-Print Network [OSTI]

    McDonald, Kirk

    Collaboration High-Power Targets Essential for Many Future Facilties ESS IFMIF ISOL/ Beams PSI APT ATW Kirk T

  9. A THz Coaxial Two-Channel Dielectric Wakefield Structure for High Gradient Acceleration

    SciTech Connect (OSTI)

    Marshall, T. C. [Columbia University, New York, NY (United States); Omega-P, Inc., New Haven, CT (United States); Sotnikov, G. V. [Omega-P, Inc., New Haven, CT (United States); NSC Kharkov Institute of Physics and Technology, Kharkov (Ukraine); Hirshfield, J. L. [Omega-P, Inc., New Haven, CT (United States); Yale University, New Haven, CT (United States)

    2010-11-04T23:59:59.000Z

    A coaxial two-channel dielectric wakefield structure is examined for use as a high gradient accelerator. A THz design, having radius {approx}1 mm, is shown to provide GeV/m--level acceleration gradient, high transformer ratio, and stable accelerated bunch motion when excited by a stable-moving 5-GeV 6-nC annular drive bunch.

  10. Development of Ultra High Gradient and High Q{sub 0} Superconducting Radio Frequency Cavities

    SciTech Connect (OSTI)

    Geng, Rongli [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Clemens, William A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Follkie, James E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Harris, Teena M. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Kushnick, Peter W. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Machie, Danny [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Martin, Robert E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Palczewski, Ari D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Perry, Era A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Slack, Gary L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Williams, R. S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Adolphsen, C. [SLAC, Menlo Park, California, (United States); Li, Z. [SLAC, Menlo Park, California, (United States); Hao, J. K. [Peking University, Beijing (China); Li, Y. M. [Peking University, Beijing (China); Liu, K. X. [Peking University, Beijing (China)

    2013-06-01T23:59:59.000Z

    We report on the recent progress at Jefferson Lab in developing ultra high gradient and high Q{sub 0} superconducting radio frequency (SRF) cavities for future SRF based machines. A new 1300 MHz 9-cell prototype cavity is being fabricated. This cavity has an optimized shape in terms of the ratio of the peak surface field (both magnetic and electric) to the acceleration gradient, hence the name low surface field (LSF) shape. The goal of the effort is to demonstrate an acceleration gradient of 50 MV/m with Q{sub 0} of 10{sup 10} at 2 K in a 9-cell SRF cavity. Fine-grain niobium material is used. Conventional forming, machining and electron beam welding method are used for cavity fabrication. New techniques are adopted to ensure repeatable, accurate and inexpensive fabrication of components and the full assembly. The completed cavity is to be first mechanically polished to a mirror-finish, a newly acquired in-house capability at JLab, followed by the proven ILC-style processing recipe established already at JLab. In parallel, new single-cell cavities made from large-grain niobium material are made to further advance the cavity treatment and processing procedures, aiming for the demonstration of an acceleration gradient of 50 MV/m with Q{sub 0} of 2?10{sup 10} at 2K.

  11. High gradient magnetic separation of iron oxide minerals from soil clays

    E-Print Network [OSTI]

    Schulze, Darrell Gene

    1977-01-01T23:59:59.000Z

    HIGH GRADIENT MAGNETIC SEPARATION OF IRON OXIDE MINERALS FROM SOIL CLAYS A Thesis by DARRELL GENE SCHULZE Submitted to the Graduate College of Texas AIM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... December 1977 Major Subject: Soil Science HIGH GRADIENT MAGNETIC SEPARATION OF IRON OXIDE MINERALS FROM SOIL CLAYS A Thesis DARRELL GENE SCHULZE Approved as to style and content by: (Chairman of C ittee) epartm t) j (Member) (Membe December 1977...

  12. HIGH-GRADIENT, HIGH-TRANSFORMER-RATIO, DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-04-12T23:59:59.000Z

    The Phase I work reported here responds to DoE'ss stated need "...to develop improved accelerator designs that can provide very high gradient (>200 MV/m for electrons...) acceleration of intense bunches of particles." Omega-P'�s approach to this goal is through use of a ramped train of annular electron bunches to drive a coaxial dielectric wakefield accelerator (CDWA) structure. This approach is a direct extension of the CDWA concept from acceleration in wake fields caused by a single drive bunch, to the more efficient acceleration that we predict can be realized from a tailored (or ramped) train of several drive bunches. This is possible because of a much higher transformer ratio for the latter. The CDWA structure itself has a number of unique features, including: a high accelerating gradient G, potentially with G > 1 GeV/m; continuous energy coupling from drive to test bunches without transfer structures; inherent transverse focusing forces for particles in the accelerated bunch; highly stable motion of high charge annular drive bunches; acceptable alignment tolerances for a multi-section system. What is new in the present approach is that the coaxial dielectric structure is now to be energized by-not one-�but by a short train of ramped annular-shaped drive bunches moving in the outer coaxial channel of the structure. We have shown that this allows acceleration of an electron bunch traveling along the axis in the inner channel with a markedly higher transformer ratio T than for a single drive bunch. As described in this report, the structure will be a GHz-scale prototype with cm-scale transverse dimensions that is expected to confirm principles that can be applied to the design of a future THz-scale high gradient (> 500 MV/m) accelerator with mm-scale transverse dimensions. We show here a new means to significantly increase the transformer ratio T of the device, and thereby to significantly improve its suitability as a flexible and effective component in a future high energy, high gradient accelerator facility. We predict that the T of a high gradient CDWA can be increased by a substantial factor; this enhancement is dramatically greater than what has been demonstrated heretofore. This large enhancement in T that we predict arises from using a train of three or four drive bunches in which the spacing of the bunches and their respective charges are selected according to a simple principle that requires each bunch lose energy to the wakefields at the same rate, so as not to sacrifice drive beam efficiency�¢����as would be the case if one bunch exhausted its available energy while others had not. It is anticipated that results from the study proposed here can have a direct impact on design of the dielectric accelerator in a TeV-scale collider concept, and in the accelerator for an x-ray FEL.

  13. High-Gradient Tests of the Single-Cell SC Cavity with a Feedback Waveguide

    SciTech Connect (OSTI)

    Yakovlev, V.; Solyak, N.; Wu, G.; Ge, M.; Gonin, I.; Khabiboulline, T.; Ozelis, J.; Rowe, A. [Fermilab, Batavia, IL 60510 (United States); Avrakhov, P.; Kanareykin, A. [Euclid TechLabs, LLC, Solon, Ohio 44139 (United States); Rathke, J. [AES, Medford, NY 11763 (United States)

    2010-11-04T23:59:59.000Z

    Use of a superconducting (SC) traveling-wave accelerating (STWA) structure with a small phase advance per cell, rather than a standing-wave structure, may provide a significant increase in the accelerating gradient in the ILC linac [1]. For the same surface electric and magnetic fields, the STWA achieves an accelerating gradient 1.2 larger than TESLA-like standing-wave cavities. In addition, the STWA allows longer acceleration cavities, reducing the number of gaps between them. However, the STWA structure requires a SC feedback waveguide to return the few hundreds of MW of circulating RF power from the structure output to the structure input. A test single-cell cavity with feedback was designed and manufactured to demonstrate the possibility of proper processing to achieve a high accelerating gradient. The first results of high-gradient tests of a prototype 1.3 GHz single-cell cavity with feedback waveguide will be presented.

  14. Non-Fickian ionic diffusion across high-concentration gradients

    SciTech Connect (OSTI)

    Carey, A.E.; Wheatcraft, S.W. [Univ. of Nevada, Reno, NV (United States)] [Univ. of Nevada, Reno, NV (United States); Glass, R.J. [Sandia National Laboratory, Albuquerque, NM (United States)] [and others] [Sandia National Laboratory, Albuquerque, NM (United States); and others

    1995-09-01T23:59:59.000Z

    A non-Fickian physico-chemical model for electrolyte transport in high-ionic strength systems is developed and tested with laboratory experiments with copper sulfate as an example electrolyte. The new model is based on irreversible thermodynamics and uses measured mutual diffusion coefficients, varying with concentration. Compared to a traditional Fickian model, the new model predicts less diffusion and asymmetric diffusion profiles. Laboratory experiments show diffusion rates even smaller than those predicted by our non-Fickian model, suggesting that there are additional, unaccounted for processes retarding diffusion. Ionic diffusion rates maybe a limiting factor in transporting salts whose effect on fluid density will in turn significantly affect the flow regime. These findings have important implications for understanding and predicting solute transport in geologic settings where dense, saline solutions occur. 30 refs., 5 figs.

  15. Material Selection and Characterization for High Gradient RF Applications

    E-Print Network [OSTI]

    Arnau-Izquierdo, G; Heikkinen, S; Ramsvik, T; Sgobba, Stefano; Taborelli, M; Wuensch, W

    2007-01-01T23:59:59.000Z

    The selection of candidate materials for the accelerating cavities of the Compact Linear Collider (CLIC) is carried out in parallel with high power RF testing. The maximum DC breakdown field of copper, copper alloys, refractory metals, aluminium and titanium have been measured with a dedicated setup. Higher maximum fields are obtained for refractory metals and for titanium, which exhibits, however, important damages after conditioning. Fatigue behaviour of copper alloys has been studied for surface and bulk by pulsed laser irradiation and ultrasonic excitation, respectively. The selected copper alloys show consistently higher fatigue resistance than copper in both experiments. In order to obtain the best local properties in the device a possible solution is a bi-metallic assembly. Junctions of molybdenum and copper-zirconium UNS C15000 alloy, achieved by HIP (Hot Isostatic Pressing) diffusion bonding or explosion bonding were evaluated for their mechanical strength. The reliability of the results obtained wit...

  16. Gearbox Reliability Collaborative High Speed Shaft Tapered Roller Bearing Calibration

    SciTech Connect (OSTI)

    Keller, J.; Guo, Y.; McNiff, B.

    2013-10-01T23:59:59.000Z

    The National Renewable Energy Laboratory (NREL) Gearbox Reliability Collaborative (GRC) is a project investigating gearbox reliability primarily through testing and modeling. Previous dynamometer testing focused upon acquiring measurements in the planetary section of the test gearbox. Prior to these tests, the strain gages installed on the planetary bearings were calibrated in a load frame.

  17. Texas Tech Effort Overview Collaborative Research on Novel High Power

    E-Print Network [OSTI]

    Anlage, Steven

    N) · Nonlinear Transmission lines · High Power Microwave source development · High reprate rf sources · HPM wave Power Microwave breakdown · Vacuum UV Spectroscopy in atmospheric gases · Explosively driven HPM

  18. Status of ORNL/ENEA-Frascati Collaboration on IGNITOR High-Speed Pellet Injector*

    E-Print Network [OSTI]

    Status of ORNL/ENEA-Frascati Collaboration on IGNITOR High-Speed Pellet Injector* S. K. Combs, C. R June 15, 2011 #12;2! Background ­ ORNL History with High-Speed Pellet Injection ·Two-stage light gas development ·Accelerated plastic projectiles (4 and 6 mm) up to 5 km/s (single pellets) ·QUICKGUN Algorithm

  19. COLLECTION OF AIRBORNE PARTICLES BY A HIGH-GRADIENT PERMANENT MAGNETIC METHOD

    SciTech Connect (OSTI)

    Cheng, Mengdawn [ORNL; Allman, Steve L [ORNL; Ludtka, Gerard Michael [ORNL; Avens, Larry R [ORNL

    2014-01-01T23:59:59.000Z

    We report on the use of magnetic force in collection of airborne particles by a high- gradient permanent magnetic separation (HGPMS) device. Three aerosol particles of different magnetic susceptibility (NaCl, CuO, and Fe2O3) were generated in the electrical mobility size range of 10 to 200 nm and were used to study HGPMS collection. One HGPMS matrix element, made of stainless steel wool, was used in the device configuration. Three flow rates were selected to simulate the environmental wind speeds of interest to the study. Magnetic force was found to exhibit an insignificant effect on the separation of NaCl particles, even in the HGPMS configuration. Diffusion was a major mechanism in the removal of the diamagnetic particles; however, diffusion is insignificant under the influence of a high-gradient magnetic field for paramagnetic or ferromagnetic particles. The HGPMS showed high-performance collection (> 99%) of paramagnetic CuO and ferromagnetic Fe2O3 particles for particle sizes greater than or equal to 60 nm. As the wind speed increases, the influence of the magnetic force weakens, and the capability to remove particles from the gas stream diminishes. The results suggest that the HGPMS principle could be explored for development of an advanced miniaturized passive aerosol collector.

  20. Overview of high gradient SRF R&D for ILC cavities at Jefferson Lab

    SciTech Connect (OSTI)

    Geng, Rongli [JLAB

    2009-11-01T23:59:59.000Z

    We report the progress on high gradient R&D of ILC cavities at Jefferson Lab (JLab) since the Beijing workshop. Routine 9-cell cavity electropolishing (EP) processing and RF testing has been enhanced with added surface mapping and T-mapping instrumentations. 12 new 9-cell cavities (10 of them are baseline fine-grain TESLA-shape cavities: 5 built by ACCEL/Research Instruments, 4 by AES and 1 by JLab; 2 of them are alternative cavities: 1 fine-grain ICHIRO-shape cavity built by KEK/Japan industry and 1 large-grain TESLA-shape cavity built by JLab) are EP processed and tested. 76 EP cycles are accumulated, corresponding to more than 200 hours of active EP time. Field emission (FE) and quench behaviors of electropolished 9-cell cavities are studied. EP process continues to be optimized, resulting in advanced procedures and hence improved cavity performance. Several 9-cell cavities reached 35 MV/m after the first light EP processing. FE-free performance has been demonstrated in 9-cell cavities in 35-40 MV/m range. 1-cell cavity studies explore new techniques for defect removal as well as advanced integrated cavity processing. Surface studies of niobium samples electropolished together with real cavities provide new insight into the nature of field emitters. Close cooperation with the US cavity fabrication industry has been undertaking with the successful achievement of 41 MV/m for the first time in a 9-cell ILC cavity built by AES. As the size of the data set grows, it is now possible to construct gradient yield curves, from which one can see that significant progress has been made in raising the high gradient yield.

  1. Dense Plasma Focus Z-pinches for High Gradient Particle Acceleration

    SciTech Connect (OSTI)

    Tang, V; Adams, M L; Rusnak, B

    2009-07-24T23:59:59.000Z

    The final Z-pinch stage of a Dense Plasma Focus (DPF) could be used as a simple, compact, and potentially rugged plasma-based high-gradient accelerator with fields at the 100 MV/m level. In this paper we review previously published experimental beam data that indicate the feasibility of such an DPF-based accelerator, qualitatively discuss the physical acceleration processes in terms of the induced voltages, and as a starting point examine the DPF acceleration potential by numerically applying a self-consistent DPF system model that includes the induced voltage from both macroscopic and instability driven plasma dynamics. Applications to the remote detection of high explosives and a multi-staged acceleration concept are briefly discussed.

  2. A comparison of NEXRAD WSR-88D rain estimates with gauge measurements for high and low reflectivity gradient precipitation events.

    SciTech Connect (OSTI)

    Jendrowski, P.; Kelly, D. S.; Klazura, G. E.; Thomale, J. M.

    1999-04-14T23:59:59.000Z

    Rain gauge measurements were compared with radar-estimated storm total precipitation for 43 rain events that occurred at ten locations. Gauge-to-radar ratios (G/R) were computed for each case. The G/R ratio is strongly related to precipitation type, with the mean G/R slightly less than 1.00 for high-reflectivity gradient cases and greater than 2.00 (factor of 2 radar underestimation) for low-reflectivity gradient cases. both precipitation types indicated radar underestimate at the nearest ranges. However, the high-reflectivity gradient cases indicated radar overestimation at further ranges, while the low-reflectivity gradient cases indicated significant radar underestimation at all ranges. Occurrences of radar overestimates may have been related to high reflectivity returns from melting ice, bright-band effects in stratiform systems and hail from convective systems. Bright-band effects probably were responsible for improving the radar underestimates in the second range interval (50-99.9 km) for the low-reflectivity gradient cases. Other possibilities for radar overestimates are anomalous propagation (AP) of the radar beam. Smith, et al. (1996) concluded that bright band and AP lead to systematic overestimate of rainfall at intermediate ranges.

  3. Evidence of Magnetic Breakdown on the Defects With Thermally Suppressed Critical Field in High Gradient SRF Cavities

    SciTech Connect (OSTI)

    Eremeev, Grigory [JLAB; Palczewski, Ari [JLAB

    2013-09-01T23:59:59.000Z

    At SRF 2011 we presented the study of quenches in high gradient SRF cavities with dual mode excitation technique. The data differed from measurements done in 80's that indicated thermal breakdown nature of quenches in SRF cavities. In this contribution we present analysis of the data that indicates that our recent data for high gradient quenches is consistent with the magnetic breakdown on the defects with thermally suppressed critical field. From the parametric fits derived within the model we estimate the critical breakdown fields.

  4. Validation of classical density-dependent solute transport theory for stable, high-concentration-gradient brine displacements in

    E-Print Network [OSTI]

    Hassanizadeh, S. Majid

    -concentration-gradient brine displacements in coarse and medium sands S.J. Watson a,1 , D.A. Barry a,1 , R.J. Schotting b,*, S by a brine solution, under either constant head or constant volume flux conditions. The experimental data, significantly less ex- perimental research has been conducted to investigate high-concentration (e.g., brine

  5. Theory of factors limiting high gradient operation of warm accelerating structures

    SciTech Connect (OSTI)

    Nusinovich, Gregory S. [University of Maryland; Antonsen, Thomas M. [University of Maryland; Kishek, Rami [University of Maryland

    2014-07-25T23:59:59.000Z

    This final report summarizes the research performed during the time period from 8/1/2010 to 7/31/2013. It consists of two parts describing our studies in two directions: (a) analysis of factors limiting operation of dielectric-loaded accelerating (DLA) structures where the main problem is the occurrence of multipactor on dielectric surfaces, and (b) studies of effects associated with either RF magnetic or RF electric fields which may cause the RF breakdown in high-gradient metallic accelerating structures. In the studies of DLA structures, at least, two accomplishments should be mentioned: the development of a 3D non-stationary, self-consistent code describing the multipactor phenomena and yielding very good agreement with some experimental data obtained in joint ANL/NRL experiments. In the metallic structures, such phenomena as the heating and melting of micro-particles (metallic dust) by RF electric and magnetic fields in single-shot and rep-rate regimes is analyzed. Also, such processes in micro-protrusions on the structure surfaces as heating and melting due to the field emitted current and the Nottingham effect are thoroughly investigated with the account for space charge of emitted current on the field emission from the tip.

  6. A high-throughput microfluidic device to study neurite response to growth factor gradients

    E-Print Network [OSTI]

    Kothapalli, Chandrasekhar R.

    Studying neurite guidance by diffusible or substrate bound gradients is challenging with current techniques. In this study, we present the design, fabrication and utility of a microfluidic device to study neurite guidance ...

  7. Studies of the superconducting traveling wave cavity for high gradient LINAC

    E-Print Network [OSTI]

    Avrakhov, Pavel; Kanareykin, Alexei; Solyak, Nikolay; Yakovlev, Vyacheslav P

    2015-01-01T23:59:59.000Z

    Use of a traveling wave (TW) accelerating structure with a small phase advance per cell instead of standing wave may provide a significant increase of accelerating gradient in a superconducting linear accelerator. The TW section achieves an accelerating gradient 1.2-1.4 larger than TESLA-shaped standing wave cavities for the same surface electric and magnetic fields. Recent tests of an L-band single-cell cavity with a waveguide feedback demonstrated an accelerating gradient comparable to the gradient in a single-cell ILC-type cavity from the same manufacturer. This article presents the next stage of the 3- cell TW resonance ring development which will be tested in the traveling wave regime. The main simulation results of the microphonics and Lorentz Force Detuning (LFD) are also considered.

  8. High-Speed Shaft Bearing Loads Testing and Modeling in the NREL Gearbox Reliability Collaborative: Preprint

    SciTech Connect (OSTI)

    McNiff, B.; Guo, Y.; Keller, J.; Sethuraman, L.

    2014-12-01T23:59:59.000Z

    Bearing failures in the high speed output stage of the gearbox are plaguing the wind turbine industry. Accordingly, the National Renewable Energy Laboratory (NREL) Gearbox Reliability Collaborative (GRC) has performed an experimental and theoretical investigation of loads within these bearings. The purpose of this paper is to describe the instrumentation, calibrations, data post-processing and initial results from this testing and modeling effort. Measured HSS torque, bending, and bearing loads are related to model predictions. Of additional interest is examining if the shaft measurements can be simply related to bearing load measurements, eliminating the need for invasive modifications of the bearing races for such instrumentation.

  9. Effects of Temperature Gradients and Heat Fluxes on High-Temperature Oxidation

    SciTech Connect (OSTI)

    Holcomb, G.R.

    2008-04-01T23:59:59.000Z

    The effects of a temperature gradient and heat flux on point defect diffusion in protective oxide scales were examined. Irreversible thermodynamics were used to expand Fick’s first law of diffusion to include a heat-flux term—a Soret effect. Oxidation kinetics were developed for the oxidation of cobalt and of nickel doped with chromium. Research is described to verify the effects of a heat flux by oxidizing pure cobalt in a temperature gradient at 900 °C, and comparing the kinetics to isothermal oxidation. No evidence of a heat flux effect was found.

  10. Proposal to negotiate a collaboration agreement for R&D activities relating to Nb3Sn superconducting wire for the High Luminosity LHC project

    E-Print Network [OSTI]

    2015-01-01T23:59:59.000Z

    Proposal to negotiate a collaboration agreement for R&D activities relating to Nb3Sn superconducting wire for the High Luminosity LHC project

  11. Learn. Connect. Collaborate. In Spring 2012, San Jose State University hosted a highly successful Social

    E-Print Network [OSTI]

    Su, Xiao

    were created, and collaborative projects geared towards alleviating poverty in under and economic issues running in parallel to this wealth: rising poverty, increased social inequity, reduced of innovation and collaboration to address the poverty issues in our region. Together, we can create solutions

  12. Probing temperature gradients within the GaN buffer layer of AlGaN/GaN high electron mobility transistors with Raman thermography

    SciTech Connect (OSTI)

    Hodges, C., E-mail: chris.hodges@bristol.ac.uk; Pomeroy, J.; Kuball, M. [H. H. Wills Physics Laboratory, University of Bristol, Bristol BS8 1TL (United Kingdom)

    2014-02-14T23:59:59.000Z

    We demonstrate the ability of confocal Raman thermography using a spatial filter and azimuthal polarization to probe vertical temperature gradients within the GaN buffer layer of operating AlGaN/GaN high electron mobility transistors. Temperature gradients in the GaN layer are measured by using offset focal planes to minimize the contribution from different regions of the GaN buffer. The measured temperature gradient is in good agreement with a thermal simulation treating the GaN thermal conductivity as homogeneous throughout the layer and including a low thermal conductivity nucleation layer to model the heat flow between the buffer and substrate.

  13. Experimental Study of the Effect of Beam Loading on RF Breakdown Rate in CLIC High-Gradient Accelerating Structures

    E-Print Network [OSTI]

    Tecker, F; Kelisani, M; Doebert, S; Grudiev, A; Quirante, J; Riddone, G; Syratchev, I; Wuensch, W; Kononenko, O; Solodko, A; Lebet, S

    2013-01-01T23:59:59.000Z

    RF breakdown is a key issue for the multi-TeV highluminosity e+e- Compact Linear Collider (CLIC). Breakdowns in the high-gradient accelerator structures can deflect the beam and decrease the desired luminosity. The limitations of the accelerating structures due to breakdowns have been studied so far without a beam present in the structure. The presence of the beam modifies the distribution of the electrical and magnetic field distributions, which determine the breakdown rate. Therefore an experiment has been designed for high power testing a CLIC prototype accelerating structure with a beam present in the CLIC Test Facility (CTF3). A special beam line allows extracting a beam with nominal CLIC beam current and duration from the CTF3 linac. The paper describes the beam optics design for this experimental beam line and the commissioning of the experiment with beam.

  14. FLOW OF A FLUID THROUGH A POROUS SOLID DUE TO HIGH PRESSURE GRADIENTS

    E-Print Network [OSTI]

    Bonito, Andrea

    or carbon diox- ide sequestration where very high pressure differentials are involved. Another important and geotechnical engineering, for example problems such as enhanced oil recovery and carbon di-oxide sequestration

  15. Hybrid magnet devices for molecule manipulation and small scale high gradient-field applications

    DOE Patents [OSTI]

    Humphries, David E. (El Cerrito, CA); Hong, Seok-Cheol (Seoul, KR); Cozzarelli, legal representative, Linda A. (Berkeley, CA); Pollard, Martin J. (El Cerrito, CA); Cozzarelli, Nicholas R. (Berkeley, CA)

    2009-01-06T23:59:59.000Z

    The present disclosure provides a high performance hybrid magnetic structure made from a combination of permanent magnets and ferromagnetic pole materials which are assembled in a predetermined array. The hybrid magnetic structure provides means for separation and other biotechnology applications involving holding, manipulation, or separation of magnetizable molecular structures and targets. Also disclosed are hybrid magnetic tweezers able to exert approximately 1 nN of force to 4.5 .mu.m magnetic bead. The maximum force was experimentally measured to be .about.900 pN which is in good agreement with theoretical estimations and other measurements. In addition, a new analysis scheme that permits fast real-time position measurement in typical geometry of magnetic tweezers has been developed and described in detail.

  16. Generation of high order optical harmonics in steep plasma density gradients

    SciTech Connect (OSTI)

    Linde, D. von der [Institut fuer Laser- und Plasmaphysik, Universitaet Essen, D-45117 Essen (Germany)

    1998-02-20T23:59:59.000Z

    During the interaction of an intense ultrashort laser pulse with solid targets a thin layer of surface plasma is generated in which the density drops to the vacuum level in a distance much shorter than the wavelength. This sharp plasma-vacuum boundary performs an oscillatory motion in response to the electromagnetic forces of the intense laser light. It is shown that the generation of reflected harmonics can be interpreted as a phase modulation experienced by the light upon reflection from the oscillating boundary. The modulation sidebands of the reflected frequency spectrum correspond to odd and even harmonics of the laser frequency. Retardation effects lead to a strong anharmonicity for high velocities of the plasma-vacuum boundary. As a result, harmonic generation is strongly enhanced in the relativistic regime of laser intensities.

  17. The Impact of Collaborative Literacy Coaching on Middle and High School Teachers' Personal and General Sense of Efficacy for Literacy Teaching

    E-Print Network [OSTI]

    Howe, Kathleen Schmiedeler

    2012-05-31T23:59:59.000Z

    for literacy teaching. A variety of data, including but not limited to transcripts of weekly collaborative literacy coaching cadres, individual participant interviews, Initial and Follow-up Questionnaires allowed three middle and high school teachers...

  18. Collaborative multi-vehicle localization and mapping in high clutter environments

    E-Print Network [OSTI]

    Moratuwage, M. D. P.

    Among today's robotics applications, exploration missions in dynamic, high clutter and uncertain environmental conditions is quite common. Autonomous multi-vehicle systems come in handy for such exploration missions since ...

  19. Gradient elution in capillary electrochromatography

    SciTech Connect (OSTI)

    Anex, D.; Rakestraw, D.J. [Sandia National Labs., Livermore, CA (United States); Yan, Chao; Dadoo, R.; Zare, R.N. [Stanford Univ., CA (United States). Dept. of Chemistry

    1997-08-01T23:59:59.000Z

    In analogy to pressure-driven gradient techniques in high-performance liquid chromatography, a system has been developed for delivering electroosmotically-driven solvent gradients for capillary electrochromatography (CEC). Dynamic gradients with sub-mL/min flow rates are generated by merging two electroosmotic flows that are regulated by computer-controlled voltages. These flows are delivered by two fused-silica capillary arms attached to a T-connector, where they mix and then flow into a capillary column that has been electrokinetically packed with 3-mm reversed-phase particles. The inlet of one capillary arm is placed in a solution reservoir containing one mobile phase and the inlet of the other is placed in a second reservoir containing a second mobile phase. Two independent computer-controlled programmable high-voltage power supplies (0-50 kV)--one providing an increasing ramp and the other providing a decreasing ramp--are used to apply variable high-voltage potentials to the mobile phase reservoirs to regulate the electroosmotic flow in each arm. The ratio of the electroosmotic flow rates between the two arms is changed with time according to the computer-controlled voltages to deliver the required gradient profile to the separation column. Experiments were performed to confirm the composition of the mobile phase during a gradient run and to determine the change of the composition in response to the programmed voltage profile. To demonstrate the performance of electroosmotically-driven gradient elution in CEC, a mixture of 16 polycyclic aromatic hydrocarbons (PAHs) was separated in less than 90 minutes. This gradient technique is expected to be well-suited for generating not only solvent gradients in CEC, but also other types of gradients such as pH- and ionic-strength gradients in capillary electrokinetic separations and analyses.

  20. Collaboration Multidisciplinary

    E-Print Network [OSTI]

    Bigelow, Stephen

    ;Main Research Themes Biology & Biomedical New tools and diagnostics that can directly probe and the talent that will continue to fuel innovation in Nanosystems To foster interdisciplinary collaboration.csqc.ucsb.edu Center for Stem Cell Biology and Engineering www.stemcell.ucsb.edu Institute for Collaborative

  1. Collaboration, Automation, and Information Management at Hanford High Level Radioactive Waste (HLW) Tank Farms

    SciTech Connect (OSTI)

    Aurah, Mirwaise Y.; Roberts, Mark A.

    2013-12-12T23:59:59.000Z

    Washington River Protection Solutions (WRPS), operator of High Level Radioactive Waste (HLW) Tank Farms at the Hanford Site, is taking an over 20-year leap in technology, replacing systems that were monitored with clipboards and obsolete computer systems, as well as solving major operations and maintenance hurdles in the area of process automation and information management. While WRPS is fully compliant with procedures and regulations, the current systems are not integrated and do not share data efficiently, hampering how information is obtained and managed.

  2. On the fast track: Collaboration expedites adoption of efficient irrigation technologies in the High Plains

    E-Print Network [OSTI]

    Lee, Leslie

    2013-01-01T23:59:59.000Z

    too much #24;eld slope, then I run too much risk of losing water to runo#21;. So, none of these work everywhere.? She said that it?s also important for her and her peers to be realistic about new technologies. ?When we talk about new research, it...?s so important to spell-out clearly the details, the speci#24;c conditions under which the results were achieved,? Porter said. ?A new technology isn?t a magic #24;x.? Working together In the High Plains, AgriLife Extension focuses on helping...

  3. The development of a high-throughput gradient array apparatus for the study of porous polymer networks.

    SciTech Connect (OSTI)

    Majumdar, Partha (North Dakota State University, Fargo, ND); Lee, Elizabeth (North Dakota State University, Fargo, ND); Chisholm, Bret J. (North Dakota State University, Fargo, ND); Dirk, Shawn M.; Weisz, Michael (North Dakota State University, Fargo, ND); Bahr, James (North Dakota State University, Fargo, ND); Schiele, Kris (North Dakota State University, Fargo, ND)

    2010-01-01T23:59:59.000Z

    A gradient array apparatus was constructed for the study of porous polymers produced using the process of chemically-induced phase separation (CIPS). The apparatus consisted of a 60 element, two-dimensional array in which a temperature gradient was placed in the y-direction and composition was varied in the x-direction. The apparatus allowed for changes in opacity of blends to be monitored as a function of temperature and cure time by taking images of the array with time. The apparatus was validated by dispense a single blend composition into all 60 wells of the array and curing them for 24 hours and doing the experiment in triplicate. Variations in micron scale phase separation were readily observed as a function of both curing time and temperature and there was very good well-to-well consistency as well as trial-to-trial consistency. Poragen of samples varying with respect to cure temperature was removed and SEM images were obtained. The results obtained showed that cure temperature had a dramatic affect on sample morphology, and combining data obtained from visual observations made during the curing process with SEM data can enable a much better understanding of the CIPS process and provide predictive capability through the relatively facile generation of composition-process-morphology relationships. Data quality could be greatly enhanced by making further improvements in the apparatus. The primary improvements contemplated include the use of a more uniform light source, an optical table, and a CCD camera with data analysis software. These improvements would enable quantification of the amount of scattered light generated from individual elements as a function of cure time. In addition to the gradient array development, porous composites were produced by incorporating metal particles into a blend of poragen, epoxy resin, and crosslinker. The variables involved in the experiment were metal particle composition, primary metal particle size, metal concentration, and poragen composition. A total of 16 different porous composites were produced and characterized using SEM. In general, the results showed that pore morphology and the distribution of metal particles was dependent on multiple factors. For example, the use of silver nanoparticles did not significantly affect pore morphology for composites derived from decanol as the poragen, but exceptionally large pores were obtained with the use of decane as the poragen. With regard to the effect of metal particle size, silver nanoparticles were essentially exclusively dispered in the polymer matrix while silver microparticles were found in pores. For nickel particles, both nanoparticles and microparticles were largely dispersed in the polymer matrix and not in the pores.

  4. Introduction Conjugate Gradient Method

    E-Print Network [OSTI]

    Vuik, Kees

    Introduction Conjugate Gradient Method Deflation Domain Decomposition Research Master Thesis Presentation #12;Introduction Conjugate Gradient Method Deflation Domain Decomposition Research Plaxis Finite Kaliszka Master Thesis Literature Study Presentation #12;Introduction Conjugate Gradient Method Deflation

  5. Charting Collaborative Practices: Acknowledgements

    E-Print Network [OSTI]

    Belanger, Alisa; Crumly, Allison

    2009-01-01T23:59:59.000Z

    Collaborative Practices: Acknowledgements Each issue ofCollaborative Practices: Acknowledgements Alisa Belanger and

  6. An evaluation of the TSE MR sequence for time efficient data acquisition in polymer gel dosimetry of applications involving high doses and steep dose gradients

    SciTech Connect (OSTI)

    Baras, P.; Seimenis, I.; Sandilos, P.; Vlahos, L.; Bieganski, T.; Georgiou, E.; Pantelis, E.; Papagiannis, P.; Sakelliou, L. [Philips Hellas Medical Systems, 44 Kifissias Ave., Maroussi 151 25, Athens (Greece); Department of Radiology, Medical School, University of Athens, Areteion Hospital, 76 Vas. Sofias Ave., 115 28 Athens (Greece) and Medical Physics Department, Hygeia Hospital, Kiffisias Avenue, 24 Erythrou Stavrou, Marousi, 151 23, Athens (Greece); Department of Radiology, Mother's Memorial Hospital, Rzgowska 281/289, 93-388, Lodz (Poland); Medical Physics Department, University of Athens, 75 Mikras Asias, 115 27 Athens (Greece); Nuclear and Particle Physics Section, Physics Department, University of Athens, Panepistimioupolis, Ilisia, 157 71 Athens (Greece)

    2005-11-15T23:59:59.000Z

    The use of magnetic resonance imaging as a readout method for polymer gel dosimetry commonly involves long imaging sessions, particularly when high spatial resolution is required in all three dimensions, for the investigation of dose distributions with steep dose gradients and stringent dose delivery specifications. In this work, a volume selective turbo spin echo (TSE) pulse sequence is compared to the established Carr-Purcell-Meiboom-Gill (CPMG) multiecho acquisition with regard to providing accurate dosimetric results in significantly reduced imaging times. Polyethylene glycol diacrylate based (PABIG) gels were irradiated and subsequently scanned to obtain R2 relaxation rate measurements, using a CPMG multiecho sequence and a dual echo TSE utilizing an acceleration (turbo) factor of 64. R2 values, plotted against corresponding Monte Carlo dose calculations, provided calibration data of PABIG gels dose response over a wide dose range. A linear R2 versus dose relationship was demonstrated for both sequences with TSE results presenting reduced dose sensitivity. Although TSE data were found to deviate from linearity at lower doses compared to CPMG data, a relatively wide dynamic dose range of response extending up to approximately 100 Gy was observed for both sequences. The TSE and CPMG sequences were evaluated with a brachytherapy irradiation using a high dose rate {sup 192}Ir source and a gamma knife stereotactic radiosurgery irradiation with a single 4 mm collimator helmet shot. Dosimetric results obtained with the TSE and CPMG are shown to compare equally well with the expected dose distributions for these irradiations. The 60-fold scan time reduction achieved with TSE implies that this sequence could prove to be a useful tool for the introduction of polymer gel dosimetry in clinical radiation therapy applications involving high doses and steep dose gradients.

  7. ARM - Collaborations

    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 492air Comments? We would love to heargovInstrumentstdma Comments?History OrganizationTwistCollaborations

  8. ARM - Collaborations

    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 492air Comments? We would love to heargovInstrumentstdma Comments?HistoryArctic ResearchCollaborations

  9. Converting Level Set Gradients to Shape Gradients

    E-Print Network [OSTI]

    Radke, Rich

    distance function (SDF) associated with a shape, and differentiate these energies with respect to the SDF to the SDF. We discuss some problematic gradients from the literature, show how they can easily be fixed function (SDF) of , i.e. the function that associates any point x with the signed distance (x) = ±d

  10. California Geothermal Energy Collaborative

    E-Print Network [OSTI]

    California Geothermal Energy Collaborative Geothermal Education and Outreach Guide of California Davis, and the California Geothermal Energy Collaborative. We specifically would like to thank support of the California Geothermal Energy Collaborative. We also thank Charlene Wardlow of Ormat for her

  11. Exploiting Matrix Symmetry to Improve FPGA-Accelerated Conjugate Gradient

    E-Print Network [OSTI]

    Bakos, Jason D.

    the Conjugate Gradient (CG) method using an FPGA co-processor. As in previous approaches, our coExploiting Matrix Symmetry to Improve FPGA- Accelerated Conjugate Gradient Jason D. Bakos, Krishna, high- performance computing, sparse matrix vector multiply, conjugate gradient I. INTRODUCTION Linear

  12. Collaborative Estimation of Gradient Direction by a Formation of AUVs

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    underwater vehicles). The present paper proposes a distributed solution in which a group of vehicles and unmanned air vehicles (AUVs and UAVs) [6, 7]. Cooperative formation control and motion co- ordination have-agent systems [1, 2], flocking [3], distributed sensor networks [4, 5], and autonomous sys- tems as underwater

  13. Shape reconstruction from gradient data

    SciTech Connect (OSTI)

    Ettl, Svenja; Kaminski, Juergen; Knauer, Markus C.; Haeusler, Gerd

    2008-04-20T23:59:59.000Z

    We present a generalized method for reconstructing the shape of an object from measured gradient data. A certain class of optical sensors does not measure the shape of an object but rather its local slope. These sensors display several advantages, including high information efficiency, sensitivity, and robustness. For many applications, however, it is necessary to acquire the shape, which must be calculated from the slopes by numerical integration. Existing integration techniques show drawbacks that render them unusable in many cases. Our method is based on an approximation employing radial basis functions. It can be applied to irregularly sampled, noisy, and incomplete data, and it reconstructs surfaces both locally and globally with high accuracy.

  14. LINUDANS -Research and development of high voltage towers. Reykjavik University is working in Collaboration with Linudans, research based company specialized

    E-Print Network [OSTI]

    Karlsson, Brynjar

    LINUDANS - Research and development of high voltage towers. Reykjavik University is working problems regarding the growing energy transport. All products of Linudans are green and environmentally voltage towers is the main focus of Linudans. The company has developed an innovative concept which serves

  15. Conjugate Gradient Method Numerisches Rechnen

    E-Print Network [OSTI]

    Conjugate Gradient Method Numerisches Rechnen (für Informatiker) M. Grepl J. Berger & J.T. Frings Numerisches Rechnen #12;Conjugate Gradient Method The Quadratic Form Steepest Descent Conjugate Directions/Gradients IGPM, RWTH Aachen Numerisches Rechnen #12;Conjugate Gradient Method The Quadratic Form Steepest Descent

  16. Hot Pot Contoured Temperature Gradient Map

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

    Lane, Michael

    Temperature gradient contours derived from Oski temperature gradient hole program and from earlier published information.

  17. Hot Pot Contoured Temperature Gradient Map

    SciTech Connect (OSTI)

    Lane, Michael

    2013-06-28T23:59:59.000Z

    Temperature gradient contours derived from Oski temperature gradient hole program and from earlier published information.

  18. Conjugate Gradient Methods in Confirmatory Factor Analysis

    E-Print Network [OSTI]

    Jamshardian, Mortaza; Jennrich, Robert

    1993-01-01T23:59:59.000Z

    R. I. (1988), "Conjugate Gradient Methods in Confirmatoryapply generalized conjugate gradient methods in an attemptby used. The conjugate gradient method, which is simple and

  19. Conjugate Gradient Acceleration of the EM Algorithm

    E-Print Network [OSTI]

    Mortaza Jamshidian; Robert Jennrich

    2011-01-01T23:59:59.000Z

    R. I. (1988), "Conjugate Gradient Methods in Confirmatoryapply generalized conjugate gradient methods in an attemptby used. The conjugate gradient method, which is simple and

  20. Collaborative Construction of Task Activity: Coordinating Multiple Resources in a

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Collaborative Construction of Task Activity: Coordinating Multiple Resources in a High School of the moment-to- moment construction of task, this study draws attention to complex yet taken-for- granted connections, knowing how to collaboratively construct a task. This article documents the collaborative

  1. Fourier Accelerated Conjugate Gradient Lattice Gauge Fixing

    E-Print Network [OSTI]

    R. J. Hudspith

    2014-05-22T23:59:59.000Z

    We provide details of the first implementation of a non-linear conjugate gradient method for Landau and Coulomb gauge fixing with Fourier acceleration. We find clear improvement over the Fourier accelerated steepest descent method, with the average time taken for the algorithm to converge to a fixed, high accuracy, being reduced by a factor of 2 to 4.

  2. Short wavelength ion temperature gradient turbulence

    SciTech Connect (OSTI)

    Chowdhury, J.; Ganesh, R. [Institute for Plasma Research, Bhat, Gandhinagar (India); Brunner, S.; Lapillonne, X.; Villard, L. [CRPP, Association EURATOM-Confederation Suisse, EPFL, 1015 Lausanne (Switzerland); Jenko, F. [Max-Planck-Institut fuer Plasmaphysik Boltzmannstr. 2, D-85748 Garching (Germany)

    2012-10-15T23:59:59.000Z

    The ion temperature gradient (ITG) mode in the high wavenumber regime (k{sub y}{rho}{sub s}>1), referred to as short wavelength ion temperature gradient mode (SWITG) is studied using the nonlinear gyrokinetic electromagnetic code GENE. It is shown that, although the SWITG mode may be linearly more unstable than the standard long wavelength (k{sub y}{rho}{sub s}<1) ITG mode, nonlinearly its contribution to the total thermal ion heat transport is found to be low. We interpret this as resulting from an increased zonal flow shearing effect on the SWITG mode suppression.

  3. Experimental determination of the radial dose distribution in high gradient regions around {sup 192}Ir wires: Comparison of electron paramagnetic resonance imaging, films, and Monte Carlo simulations

    SciTech Connect (OSTI)

    Kolbun, N.; Leveque, Ph.; Abboud, F.; Bol, A.; Vynckier, S.; Gallez, B. [Biomedical Magnetic Resonance Unit, Louvain Drug Research Institute, Universite catholique de Louvain, Avenue Mounier 73.40, B-1200 Brussels (Belgium); Molecular Imaging and Experimental Radiotherapy Unit, Institute of Experimental and Clinical Research, Universite catholique de Louvain, Avenue Hippocrate 55, B-1200 Brussels (Belgium); Biomedical Magnetic Resonance Unit, Louvain Drug Research Institute, Universite catholique de Louvain, Avenue Mounier 73.40, B-1200 Brussels (Belgium)

    2010-10-15T23:59:59.000Z

    Purpose: The experimental determination of doses at proximal distances from radioactive sources is difficult because of the steepness of the dose gradient. The goal of this study was to determine the relative radial dose distribution for a low dose rate {sup 192}Ir wire source using electron paramagnetic resonance imaging (EPRI) and to compare the results to those obtained using Gafchromic EBT film dosimetry and Monte Carlo (MC) simulations. Methods: Lithium formate and ammonium formate were chosen as the EPR dosimetric materials and were used to form cylindrical phantoms. The dose distribution of the stable radiation-induced free radicals in the lithium formate and ammonium formate phantoms was assessed by EPRI. EBT films were also inserted inside in ammonium formate phantoms for comparison. MC simulation was performed using the MCNP4C2 software code. Results: The radical signal in irradiated ammonium formate is contained in a single narrow EPR line, with an EPR peak-to-peak linewidth narrower than that of lithium formate ({approx}0.64 and 1.4 mT, respectively). The spatial resolution of EPR images was enhanced by a factor of 2.3 using ammonium formate compared to lithium formate because its linewidth is about 0.75 mT narrower than that of lithium formate. The EPRI results were consistent to within 1% with those of Gafchromic EBT films and MC simulations at distances from 1.0 to 2.9 mm. The radial dose values obtained by EPRI were about 4% lower at distances from 2.9 to 4.0 mm than those determined by MC simulation and EBT film dosimetry. Conclusions: Ammonium formate is a suitable material under certain conditions for use in brachytherapy dosimetry using EPRI. In this study, the authors demonstrated that the EPRI technique allows the estimation of the relative radial dose distribution at short distances for a {sup 192}Ir wire source.

  4. Energy in density gradient

    E-Print Network [OSTI]

    Vranjes, J

    2015-01-01T23:59:59.000Z

    Inhomogeneous plasmas and fluids contain energy stored in inhomogeneity and they naturally tend to relax into lower energy states by developing instabilities or by diffusion. But the actual amount of energy in such inhomogeneities has remained unknown. In the present work the amount of energy stored in a density gradient is calculated for several specific density profiles in a cylindric configuration. This is of practical importance for drift wave instability in various plasmas, and in particular in its application in models dealing with the heating of solar corona because the instability is accompanied with stochastic heating, so the energy contained in inhomogeneity is effectively transformed into heat. It is shown that even for a rather moderate increase of the density at the axis in magnetic structures in the corona by a factor 1.5 or 3, the amount of excess energy per unit volume stored in such a density gradient becomes several orders of magnitude greater than the amount of total energy losses per unit ...

  5. Collaborative Lubricating Oil Study on Emissions (CLOSE) Project...

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

    CLOSE) Project Collaborative Lubricating Oil Study on Emissions (CLOSE) Project Extensive chemical and physical characterization performed on emissions from normal and high...

  6. Modelling Flow through Porous Media under Large Pressure Gradients

    E-Print Network [OSTI]

    Srinivasan, Shriram

    2013-11-01T23:59:59.000Z

    The most interesting and technologically important problems in the study of flow through porous media involve very high pressures and pressure gradients in the flow do- main such as enhanced oil recovery and carbon dioxide sequestration. The popular...

  7. alternating gradient synchrotron: Topics by E-print Network

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

    sources also have the advantage of a time structure with a high peak neutron flux. The basic requirement is for a... Bryant, P J 1995-01-01 36 Gradient House. Open...

  8. Rapid Migration of Radionuclides Leaked from High-Level Water Tanks; A Study of Salinity Gradients, Wetted Path Geometry and Water Vapor Transport

    SciTech Connect (OSTI)

    Anderson l. Ward; Glendon W. Gee; John S. Selker; Clay Cooper

    2002-04-24T23:59:59.000Z

    The basis of this study was the hypothesis that the physical and chemical properties of hypersaline tank waste could lead to wetting from instability and fingered flow following a tank leak. Thus, the goal of this project was to develop an understanding of the impacts of the properties of hypersaline fluids on transport through the unsaturated zone beneath Hanford's Tank Farms. There were three specific objectives (i) to develop an improved conceptualization of hypersaline fluid transport in laboratory (ii) to identify the degree to which field conditions mimic the flow processes observed in the laboratory and (iii) to provide a validation data set to establish the degree to which the conceptual models, embodied in a numerical simulator, could explain the observed field behavior. As hypothesized, high ionic strength solutions entering homogeneous pre-wetted porous media formed unstable wetting fronts atypical of low ionic strength infiltration. In the field, this mechanism could for ce flow in vertical flow paths, 5-15 cm in width, bypassing much of the media and leading to waste penetration to greater depths than would be predicted by current conceptual models. Preferential flow may lead to highly accelerated transport through large homogeneous units, and must be included in any conservative analysis of tank waste losses through coarse-textured units. However, numerical description of fingered flow using current techniques has been unreliable, thereby precluding tank-scale 3-D simulation of these processes. A new approach based on nonzero, hysteretic contract angles and fluid-dependent liquid entry has been developed for the continuum scale modeling of fingered flow. This approach has been coupled with and adaptive-grid finite-difference solver to permit the prediction of finger formation and persistence form sub centimeter scales to the filed scale using both scalar and vector processors. Although laboratory experiments demonstrated that elevated surface tens ion of imbibing solutions can enhance vertical fingered flow, this phenomenon was not observed in the field. Field tests showed that the fingered flow behavior was overwhelmed by the variability in texture resulting from differences in the depositional environment. Field plumes were characterized by lateral spreading with an average width to depth aspect ratio of 4. For both vertical fingers and lateral flow, the high ionic strength contributed to the vapor phase dilution of the waste, which increased waste volume and pushed the wetting from well beyond what would have occurred if the volume of material had remained unchanged from that initially released into the system. It was also observed that following significant vapor-phase dilution of this waste simulants that streams of colloids were ejected from the sediment surfaces. It was shown that due to the high-sodium content of the tank wastes the colloids were deflocculated below a critical salt concentration in Hanford sediments. Th e released colloids, which at the site would be expected to carry the bulk of the sorbed heavy metals and radioisotopes, were mobile though coarse Hanford sediments, but clogged finer layers. The developments resulting from this study are already being applied at Hanford in the nonisothermal prediction of the hypersaline, high pH waste migration in tank farms and in the development of inverse methods for history matching under DOE's Groundwater/Vadose Zone Integration Project at Hanford.

  9. Rapid Migration of Radionuclides Leaked from High-Level Water Tanks: A Study of Salinity Gradients, Wetted Path Geometry and Water Vapor Transport

    SciTech Connect (OSTI)

    Anderson L. Ward; Glendon W. Gee; John S. Selker; Caly Cooper

    2002-04-24T23:59:59.000Z

    The basis of this study was the hypothesis that the physical and chemical properties of hypersaline tank waste could lead to wetting from instability and fingered flow following a tank leak. Thus, the goal of this project was to develop an understanding of the impacts of the properties of hypersaline fluids on transport through the unsaturated zone beneath Hanford's Tank Farms. There were three specific objectives (i) to develop an improved conceptualization of hypersaline fluid transport in laboratory (ii) to identify the degree to which field conditions mimic the flow processes observed in the laboratory and (iii) to provide a validation data set to establish the degree to which the conceptual models, embodied in a numerical simulator, could explain the observed field behavior. As hypothesized, high ionic strength solutions entering homogeneous pre-wetted porous media formed unstable wetting fronts a typical of low ionic strength infiltration. In the field, this mechanism could force flow in vertical flow paths, 5-15 cm in width, bypassing much of the media and leading to waste penetration to greater depths than would be predicted by current conceptual models. Preferential flow may lead to highly accelerated transport through large homogeneous units, and must be included in any conservative analysis of tank waste losses through coarse-textured units. However, numerical description of fingered flow using current techniques has been unreliable, thereby precluding tank-scale 3-D simulation of these processes. A new approach based on nonzero, hysteretic contact angles and fluid-dependent liquid entry has been developed for the continuum scale modeling of fingered flow. This approach has been coupled with and adaptive-grid finite-difference solver to permit the prediction of finger formation and persistence form sub centimeter scales to the filed scale using both scalar and vector processors. Although laboratory experiments demonstrated that elevated surface tension of imbibing solutions can enhance vertical fingered flow, this phenomenon was not observed in the field. Field tests of showed that the fingered flow behavior was overwhelmed by the variability in texture resulting from differences in the depositional environment. Field plumes were characterized by lateral spreading with an average width to depth aspect ratio of 4. For both vertical fingers and lateral flow, the high ionic strength contributed to the vapor phase dilution of the waste, which increased waste volume and pushed the wetting from well beyond what would have occurred if the volume of material had remained unchanged from that initially released into the system. It was also observed that following significant vapor-phase dilution of the waste simulants that streams of colloids were ejected from the sediment surfaces. It was shown that due to the high-sodium content of the tank wastes the colloids were deflocculated below a critical salt concentration in Hanford sediment s. The released colloids, which at the site would be expected to carry the bulk of the sorbed heavy metals and radioisotopes, were mobile though coarse Hanford sediments, but clogged finer layers. The developments resulting from this study are already being applied at Hanford in the nonisothermal prediction of the hypersaline, high pH waste migration in tank farms and in the development of inverse methods for history matching under DOE's Groundwater/Vadose Zone Integration Project at Hanford.

  10. Block-conjugate-gradient method

    SciTech Connect (OSTI)

    McCarthy, J.F. (Department of Physics, Indiana University, Bloomington, Indiana 47405 (US))

    1989-09-15T23:59:59.000Z

    It is shown that by using the block-conjugate-gradient method several, say {ital s}, columns of the inverse Kogut-Susskind fermion matrix can be found simultaneously, in less time than it would take to run the standard conjugate-gradient algorithm {ital s} times. The method improves in efficiency relative to the standard conjugate-gradient algorithm as the fermion mass is decreased and as the value of the coupling is pushed to its limit before the finite-size effects become important. Thus it is potentially useful for measuring propagators in large lattice-gauge-theory calculations of the particle spectrum.

  11. CONJUGATE GRADIENT WITH SUBSPACE OPTIMIZATION 1 ...

    E-Print Network [OSTI]

    2011-12-25T23:59:59.000Z

    last update. Unlike some other conjugate gradient methods, our algorithm attains a theoretical ... The method of conjugate gradients (CG) was introduced by.

  12. Towards Efficient Collaboration in Cyber Security

    SciTech Connect (OSTI)

    Hui, Peter SY; Bruce, Joseph R.; Fink, Glenn A.; Gregory, Michelle L.; Best, Daniel M.; McGrath, Liam R.; Endert, Alexander

    2010-06-03T23:59:59.000Z

    Cyber security analysts in different geographical and organizational domains are often largely tasked with similar duties, albeit with domain-specific variations. These analysts necessarily perform much of the same work independently— for instance, analyzing the same list of security bulletins released by largely the same set of software vendors. As such, communication and collaboration between such analysts would be mutually beneficial to the analysts involved, potentially reducing redundancy and offering the opportunity to preemptively alert each other to high-severity security alerts in a more timely fashion. However, several barriers to practical and efficient collaboration exist, and as such, no such framework exists to support such efforts. In this paper, we discuss the inherent difficulties which make efficient collaboration between cyber security analysts a difficult goal to achieve. We discuss preliminary ideas and concepts towards a collaborative cyber-security framework currently under development, whose goal is to facilitate analyst collaboration across these boundaries. While still in its early stages, we describe work-in-progress towards achieving this goal, including motivation, functionality, concepts, and a high-level description of the proposed system architecture.

  13. To Collaborative LIfe Sciences Building

    E-Print Network [OSTI]

    To Collaborative LIfe Sciences Building To Professional Development Center Collaborative Life Sciences Building SW MEADE SW PORTER SW M OODY I-5 To Main Campus To South Waterfront I-405 Collaborative Life Sciences Building 0650 SW Meade St. Academic & Student Recreation Center (ASRC) C8 Art Building

  14. Collaboration Topics - Visualization | National Nuclear Security...

    National Nuclear Security Administration (NNSA)

    Simulation and Computing and Institutional R&D Programs NNSACEA Cooperation in Computer Science Collaboration Topics - Visualization Collaboration Topics - Visualization...

  15. Japanese Computing Center Discusses Potential Collaborations...

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

    Japanese Computing Center Discusses Potential Collaborations Japanese Computing Center Discusses Potential Collaborations February 26, 2011 Representatives from Japan's Tsukuba...

  16. International Collaborations on Engineered Barrier Systems: Experiment...

    Energy Savers [EERE]

    International Collaborations on Engineered Barrier Systems: Experimental and Modeling Investigations International Collaborations on Engineered Barrier Systems: Experimental and...

  17. Gas Exchange, Partial Pressure Gradients,

    E-Print Network [OSTI]

    Riba Sagarra, Jaume

    Gas Exchange, Partial Pressure Gradients, and the Oxygen Window Johnny E. Brian, Jr., M of circulatory and gas transport physiology, and the best place to start is with normobaric physiology. LIFE affect the precise gas exchange occurring in individual areas of the lungs and body tissues. To make

  18. Variable metric conjugate gradient methods

    SciTech Connect (OSTI)

    Barth, T.; Manteuffel, T.

    1994-07-01T23:59:59.000Z

    1.1 Motivation. In this paper we present a framework that includes many well known iterative methods for the solution of nonsymmetric linear systems of equations, Ax = b. Section 2 begins with a brief review of the conjugate gradient method. Next, we describe a broader class of methods, known as projection methods, to which the conjugate gradient (CG) method and most conjugate gradient-like methods belong. The concept of a method having either a fixed or a variable metric is introduced. Methods that have a metric are referred to as either fixed or variable metric methods. Some relationships between projection methods and fixed (variable) metric methods are discussed. The main emphasis of the remainder of this paper is on variable metric methods. In Section 3 we show how the biconjugate gradient (BCG), and the quasi-minimal residual (QMR) methods fit into this framework as variable metric methods. By modifying the underlying Lanczos biorthogonalization process used in the implementation of BCG and QMR, we obtain other variable metric methods. These, we refer to as generalizations of BCG and QMR.

  19. Alliance for Computational Science Collaboration: HBCU Partnership at Alabama A&M University Continuing High Performance Computing Research and Education at AAMU

    SciTech Connect (OSTI)

    Qian, Xiaoqing; Deng, Z. T.

    2009-11-10T23:59:59.000Z

    This is the final report for the Department of Energy (DOE) project DE-FG02-06ER25746, entitled, "Continuing High Performance Computing Research and Education at AAMU". This three-year project was started in August 15, 2006, and it was ended in August 14, 2009. The objective of this project was to enhance high performance computing research and education capabilities at Alabama A&M University (AAMU), and to train African-American and other minority students and scientists in the computational science field for eventual employment with DOE. AAMU has successfully completed all the proposed research and educational tasks. Through the support of DOE, AAMU was able to provide opportunities to minority students through summer interns and DOE computational science scholarship program. In the past three years, AAMU (1). Supported three graduate research assistants in image processing for hypersonic shockwave control experiment and in computational science related area; (2). Recruited and provided full financial support for six AAMU undergraduate summer research interns to participate Research Alliance in Math and Science (RAMS) program at Oak Ridge National Lab (ORNL); (3). Awarded highly competitive 30 DOE High Performance Computing Scholarships ($1500 each) to qualified top AAMU undergraduate students in science and engineering majors; (4). Improved high performance computing laboratory at AAMU with the addition of three high performance Linux workstations; (5). Conducted image analysis for electromagnetic shockwave control experiment and computation of shockwave interactions to verify the design and operation of AAMU-Supersonic wind tunnel. The high performance computing research and education activities at AAMU created great impact to minority students. As praised by Accreditation Board for Engineering and Technology (ABET) in 2009, ?The work on high performance computing that is funded by the Department of Energy provides scholarships to undergraduate students as computational science scholars. This is a wonderful opportunity to recruit under-represented students.? Three ASEE papers were published in 2007, 2008 and 2009 proceedings of ASEE Annual Conferences, respectively. Presentations of these papers were also made at the ASEE Annual Conferences. It is very critical to continue the research and education activities.

  20. State Technologies Advancement Collaborative

    SciTech Connect (OSTI)

    David S. Terry

    2012-01-30T23:59:59.000Z

    The U. S. Department of Energy (DOE), National Association of State Energy Officials (NASEO), and Association of State Energy Research and Technology Transfer Institutions (ASERTTI) signed an intergovernmental agreement on November 14, 2002, that allowed states and territories and the Federal Government to better collaborate on energy research, development, demonstration and deployment (RDD&D) projects. The agreement established the State Technologies Advancement Collaborative (STAC) which allowed the states and DOE to move RDD&D forward using an innovative competitive project selection and funding process. A cooperative agreement between DOE and NASEO served as the contracting instrument for this innovative federal-state partnership obligating funds from DOE's Office of Energy Efficiency and Renewable Energy and Office of Fossil Energy to plan, fund, and implement RDD&D projects that were consistent with the common priorities of the states and DOE. DOE's Golden Field Office provided Federal oversight and guidance for the STAC cooperative agreement. The STAC program was built on the foundation of prior Federal-State efforts to collaborate on and engage in joint planning for RDD&D. Although STAC builds on existing, successful programs, it is important to note that it was not intended to replace other successful joint DOE/State initiatives such as the State Energy Program or EERE Special Projects. Overall the STAC process was used to fund, through three competitive solicitations, 35 successful multi-state research, development, deployment, and demonstration projects with an overall average non-federal cost share of 43%. Twenty-two states were awarded at least one prime contract, and organizations in all 50 states and some territories were involved as subcontractors in at least one STAC project. Projects were funded in seven program areas: (1) Building Technologies, (2) Industrial Technologies, (3) Transportation Technologies, (4) Distributed Energy Resources, (5) Hydrogen Technology Learning Centers, (6) Fossil Energy, and (7) Rebuild America.

  1. The Efficient Windows Collaborative

    SciTech Connect (OSTI)

    Petermann, Nils

    2006-03-31T23:59:59.000Z

    The Efficient Windows Collaborative (EWC) is a coalition of manufacturers, component suppliers, government agencies, research institutions, and others who partner to expand the market for energy efficient window products. Funded through a cooperative agreement with the U.S. Department of Energy, the EWC provides education, communication and outreach in order to transform the residential window market to 70% energy efficient products by 2005. Implementation of the EWC is managed by the Alliance to Save Energy, with support from the University of Minnesota and Lawrence Berkeley National Laboratory.

  2. Collaboration | Jefferson Lab

    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 Office511041clothAdvanced Materials Advanced. C o w l i tCollaboration March 16, 2010 During the course of the

  3. Collaboration and Outreach

    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 742EnergyOnItem NotEnergy,ARMForms AboutRESEARCH CAPABILITIES ThematerialsAbout »Collaboration and

  4. A collaborative research venture between the minerals industry and

    E-Print Network [OSTI]

    Michelson, David G.

    A collaborative research venture between the minerals industry and The University of British Columbia MDRUMINERAL DEPOSIT RESEARCH UNIT To increase the understanding of mineral deposits and highly trained geologists for employment in the minerals industry. Mission Vision MDRU

  5. COLLABORATIVE RESEARCH: TOWARDS ADVANCED UNDERSTANDING AND PREDICTIVE CAPABILITY OF CLIMATE CHANGE IN THE ARCTIC USING A HIGH-RESOLUTION REGIONAL ARCTIC CLIMATE SYSTEM MODEL

    SciTech Connect (OSTI)

    Gutowski, William J.

    2013-02-07T23:59:59.000Z

    The motivation for this project was to advance the science of climate change and prediction in the Arctic region. Its primary goals were to (i) develop a state-of-the-art Regional Arctic Climate system Model (RACM) including high-resolution atmosphere, land, ocean, sea ice and land hydrology components and (ii) to perform extended numerical experiments using high performance computers to minimize uncertainties and fundamentally improve current predictions of climate change in the northern polar regions. These goals were realized first through evaluation studies of climate system components via one-way coupling experiments. Simulations were then used to examine the effects of advancements in climate component systems on their representation of main physics, time-mean fields and to understand variability signals at scales over many years. As such this research directly addressed some of the major science objectives of the BER Climate Change Research Division (CCRD) regarding the advancement of long-term climate prediction.

  6. Geosynthetics in a salinity-gradient solar pond environment

    SciTech Connect (OSTI)

    Lichwardt, M.A.; Comer, A.I.

    1997-11-01T23:59:59.000Z

    This paper describes the latest in salinity-gradient solar pond lining systems. The high-temperature, high-salinity environment unique to a salinity-gradient solar pond resulted in failure of the geomembrane liner at the El Paso Solar Pond Test Facility after only eight years of operation. Research involved in pond reconstruction led to the selection of a lining system consisting of a flexible polypropylene (PP) geomembrane for the sidewalls and a specially formulated geosynthetic clay liner (GCL) on the bottom of the pond. The two liners have been installed and a comprehensive test program is being conducted to measure their performance. The environment encountered in a salinity-gradient solar pond will be discussed as well as material selection criteria and the design of the two liners. Preliminary results of the GCL performance monitoring will also be presented.

  7. Conjugate Gradient Algorithms Using Multiple Recursions

    E-Print Network [OSTI]

    of Colorado Much is already known about when a conjugate gradient method can be implemented with short and sufficient conditions on the iteration matrix A, in order for a conjugate gradient method to be implemented that the conjugate gradient method for unitary and shifted unitary matrices can be implemented using a single short

  8. An Introduction to the Conjugate Gradient Method

    E-Print Network [OSTI]

    Zhang, Yi

    An Introduction to the Conjugate Gradient Method Without the Agonizing Pain Edition 11 4 Jonathan Abstract The Conjugate Gradient Method is the most prominent iterative method for solving sparse systems, the Conjugate Gradient Method is a composite of simple, elegant ideas that almost anyone can understand

  9. An Introduction to the Conjugate Gradient Method

    E-Print Network [OSTI]

    Shewchuk, Jonathan

    An Introduction to the Conjugate Gradient Method Without the Agonizing Pain Edition 1 1 4 Jonathan Abstract The Conjugate Gradient Method is the most prominent iterative method for solving sparse systems, the Conjugate Gradient Method is a composite of simple, elegant ideas that almost anyone can understand

  10. Porting the NAS-NPB Conjugate Gradient

    E-Print Network [OSTI]

    Crawford, T. Daniel

    .kr/Center_for_Manycore_Programming/SNU_NPB_Suite.html NPB Benchmarks #12;! "A conjugate gradient method is used to compute an approximation to the smallestPorting the NAS-NPB Conjugate Gradient Benchmark to CUDA NVIDIA Corporation #12;Outline ! Overview coding methodologies and architectures. ! Suite of benchmarks: ! Integer Sort ! Conjugate Gradient ! CFD

  11. Accurate conjugate gradient methods for shifted systems

    E-Print Network [OSTI]

    Sleijpen, Gerard

    Accurate conjugate gradient methods for shifted systems by Jasper van den Eshof and Gerard L. G CONJUGATE GRADIENT METHODS FOR SHIFTED SYSTEMS JASPER VAN DEN ESHOF AND GERARD L. G. SLEIJPEN Abstract We present an efficient and accurate variant of the conjugate gradient method for solving families of shifted

  12. A parallel scaled conjugate-gradient

    E-Print Network [OSTI]

    Aykanat, Cevdet

    . The scaled conjugate- gradient method is a powerful technique for solving large sparse linear systems for form-factor computation. Key words: Gathering radiosity -- Scaled conjugate-gradient method -- Parallel, the Gauss--Jacobi (GJ) method is used in the solution phase. The scaled conjugate-gradient (SCG) method

  13. An Introduction to the Conjugate Gradient Method

    E-Print Network [OSTI]

    An Introduction to the Conjugate Gradient Method Without the Agonizing Pain Jonathan Richard 15213 Abstract The Conjugate Gradient Method is the most prominent iterative method for solving sparse the mumblings of their forebears. Nevertheless, the Conjugate Gradient Method is a composite of simple, elegant

  14. Accurate conjugate gradient methods for shifted systems

    E-Print Network [OSTI]

    Sleijpen, Gerard

    Accurate conjugate gradient methods for shifted systems by Jasper van den Eshof and Gerard L. G CONJUGATE GRADIENT METHODS FOR SHIFTED SYSTEMS JASPER VAN DEN ESHOF # AND GERARD L. G. SLEIJPEN # Abstract We present an e#cient and accurate variant of the conjugate gradient method for solving families

  15. Sandia National Laboratories: VT Collaboration

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

    VT Collaboration A Model for the Nation: Promoting Education and Innovation in Vermont's Electricity Sector On May 8, 2012, in Climate, Customers & Partners, Energy, Energy Surety,...

  16. Bayesian Policy Gradient and Actor-Critic Algorithms Bayesian Policy Gradient and Actor-Critic Algorithms

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Bayesian Policy Gradient and Actor-Critic Algorithms Bayesian Policy Gradient and Actor Yaakov Engel yakiengel@gmail.com Editor: Abstract Policy gradient methods are reinforcement learning algorithms that adapt a param- eterized policy by following a performance gradient estimate. Many

  17. Gradient Navigation Model for Pedestrian Dynamics

    E-Print Network [OSTI]

    Felix Dietrich; Gerta Köster

    2014-05-14T23:59:59.000Z

    We present a new microscopic ODE-based model for pedestrian dynamics: the Gradient Navigation Model. The model uses a superposition of gradients of distance functions to directly change the direction of the velocity vector. The velocity is then integrated to obtain the location. The approach differs fundamentally from force based models needing only three equations to derive the ODE system, as opposed to four in, e.g., the Social Force Model. Also, as a result, pedestrians are no longer subject to inertia. Several other advantages ensue: Model induced oscillations are avoided completely since no actual forces are present. The derivatives in the equations of motion are smooth and therefore allow the use of fast and accurate high order numerical integrators. At the same time, existence and uniqueness of the solution to the ODE system follow almost directly from the smoothness properties. In addition, we introduce a method to calibrate parameters by theoretical arguments based on empirically validated assumptions rather than by numerical tests. These parameters, combined with the accurate integration, yield simulation results with no collisions of pedestrians. Several empirically observed system phenomena emerge without the need to recalibrate the parameter set for each scenario: obstacle avoidance, lane formation, stop-and-go waves and congestion at bottlenecks. The density evolution in the latter is shown to be quantitatively close to controlled experiments. Likewise, we observe a dependence of the crowd velocity on the local density that compares well with benchmark fundamental diagrams.

  18. Pumpernickel Valley Geothermal Project Thermal Gradient Wells

    SciTech Connect (OSTI)

    Z. Adam Szybinski

    2006-01-01T23:59:59.000Z

    The Pumpernickel Valley geothermal project area is located near the eastern edge of the Sonoma Range and is positioned within the structurally complex Winnemucca fold and thrust belt of north-central Nevada. A series of approximately north-northeast-striking faults related to the Basin and Range tectonics are superimposed on the earlier structures within the project area, and are responsible for the final overall geometry and distribution of the pre-existing structural features on the property. Two of these faults, the Pumpernickel Valley fault and Edna Mountain fault, are range-bounding and display numerous characteristics typical of strike-slip fault systems. These characteristics, when combined with geophysical data from Shore (2005), indicate the presence of a pull-apart basin, formed within the releasing bend of the Pumpernickel Valley – Edna Mountain fault system. A substantial body of evidence exists, in the form of available geothermal, geological and geophysical information, to suggest that the property and the pull-apart basin host a structurally controlled, extensive geothermal field. The most evident manifestations of the geothermal activity in the valley are two areas with hot springs, seepages, and wet ground/vegetation anomalies near the Pumpernickel Valley fault, which indicate that the fault focuses the fluid up-flow. There has not been any geothermal production from the Pumpernickel Valley area, but it was the focus of a limited exploration effort by Magma Power Company. In 1974, the company drilled one exploration/temperature gradient borehole east of the Pumpernickel Valley fault and recorded a thermal gradient of 160oC/km. The 1982 temperature data from five unrelated mineral exploration holes to the north of the Magma well indicated geothermal gradients in a range from 66 to 249oC/km for wells west of the fault, and ~283oC/km in a well next to the fault. In 2005, Nevada Geothermal Power Company drilled four geothermal gradient wells, PVTG-1, -2, -3, and -4, and all four encountered geothermal fluids. The holes provided valuable water geochemistry, supporting the geothermometry results obtained from the hot springs and Magma well. The temperature data gathered from all the wells clearly indicates the presence of a major plume of thermal water centered on the Pumpernickel Valley fault, and suggests that the main plume is controlled, at least in part, by flow from this fault system. The temperature data also defines the geothermal resource with gradients >100oC/km, which covers an area a minimum of 8 km2. Structural blocks, down dropped with respect to the Pumpernickel Valley fault, may define an immediate reservoir. The geothermal system almost certainly continues beyond the recently drilled holes and might be open to the east and south, whereas the heat source responsible for the temperatures associated with this plume has not been intersected and must be at a depth greater than 920 meters (depth of the deepest well – Magma well). The geological and structural setting and other characteristics of the Pumpernickel Valley geothermal project area are markedly similar to the portions of the nearby Dixie Valley geothermal field. These similarities include, among others, the numerous, unexposed en echelon faults and large-scale pull-apart structure, which in Dixie Valley may host part of the geothermal field. The Pumpernickel Valley project area, for the majority of which Nevada Geothermal Power Company has geothermal rights, represents a geothermal site with a potential for the discovery of a relatively high temperature reservoir suitable for electric power production. Among locations not previously identified as having high geothermal potential, Pumpernickel Valley has been ranked as one of four sites with the highest potential for electrical power production in Nevada (Shevenell and Garside, 2003). Richards and Blackwell (2002) estimated the total heat loss and the preliminary production capacity for the entire Pumpernickel Valley geothermal system to be at 35MW. A more conservative estimate, for

  19. Gradient limits and SCRF performance.

    SciTech Connect (OSTI)

    Norem, J.; Pellin, M.

    2007-01-01T23:59:59.000Z

    Superconducting rf gradients are limited by a number of mechanisms, among them are field emission, multipactor, Lorentz detuning, global and local heating, quench fields, Q-Slope, assembly defects, and overall power use. We describe how each of these mechanisms interacts with the cavity fields and show how significant improvements may be possible assuming improvements in control over the cavity surface. New techniques such as Atomic Layer Deposition (ALD), the use of layered composites, Gas Cluster Ion Beam (GCIB) smoothing and Dry Ice Cleaning (DIC) have been proposed as ways to control the surface.

  20. Gradient Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetec AG Contracting JumpGove County, Kansas: EnergyGradient Resources Jump to:

  1. Preparation of Genomic DNA from Hawaiian Bobtail Squid (Euprymna scolopes) Tissue by Cesium Chloride Gradient

    E-Print Network [OSTI]

    Ruby, Edward G.

    by Cesium Chloride Gradient Centrifugation Patricia N. Lee1,2 , Margaret J. McFall-Ngai3 , Patrick Callaerts from adult bobtail squid (Euprymna scolopes) tissues by cesium chloride (CsCl) gradient centrifugation modifications of nucleic acids are inhibited by these contaminants. The method described here yields high

  2. Seasonal Changes in Bacterial and Archaeal Gene Expression Patterns across Salinity Gradients in the

    E-Print Network [OSTI]

    their metabolic activities, microbial populations mediate the impact of high gradient regions on ecologicalSeasonal Changes in Bacterial and Archaeal Gene Expression Patterns across Salinity Gradients in nitrogen and carbon metabolism in the CRCM. Initial experiments with the environmental microarrays were

  3. Collaboration Topics - Acceleration Hardware and APIs | National...

    National Nuclear Security Administration (NNSA)

    Simulation and Computing and Institutional R&D Programs NNSACEA Cooperation in Computer Science Collaboration Topics - Acceleration Hardware and APIs Collaboration Topics...

  4. Collaboration Topics - Meshing | National Nuclear Security Administrat...

    National Nuclear Security Administration (NNSA)

    Simulation and Computing and Institutional R&D Programs NNSACEA Cooperation in Computer Science Collaboration Topics - Meshing Collaboration Topics - Meshing This work...

  5. Interagency Collaboration to Address Environmental Impacts of...

    Energy Savers [EERE]

    Interagency Collaboration to Address Environmental Impacts of Shale Gas Drilling Interagency Collaboration to Address Environmental Impacts of Shale Gas Drilling April 23, 2013 -...

  6. Collaboration Shines in Materials Project Success

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

    Collaboration Shines in Materials Project Success Collaboration Shines in Materials Project Success Many Hands at Lab Lift 'World-Changing Idea' to New Heights December 12, 2013 |...

  7. Sandia National Laboratories: PV Performance Modeling Collaborative

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

    Modeling Collaborative PV Performance Modeling Collaborative's New and Improved Website Is Launched On December 10, 2014, in Computational Modeling & Simulation, Energy,...

  8. Collaboration to advance high-performance computing

    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 TWPSuccessAlamosCharacterization2Climate,CobaltCold

  9. Collaborative Monitoring and Analysis for Simulation Scientist

    SciTech Connect (OSTI)

    Tchoua, Roselyne B [ORNL] [ORNL; Klasky, Scott A [ORNL] [ORNL; Podhorszki, Norbert [ORNL] [ORNL; Khan, Ayla Y [ORNL] [ORNL; Mouallem, P. A. [North Carolina State University] [North Carolina State University; Vouk, Mladen [North Carolina State University] [North Carolina State University

    2010-01-01T23:59:59.000Z

    Collaboratively monitoring and analyzing large scale simulations from petascale computers is an important area of research and development within the scientific community. This paper addresses these issues when teams of colleagues from different research areas work together to help understand the complex data generated from these simulations. In particular, we address the issues when geographically diverse teams of disparate researchers work together to understand the complex science being simulation on high performance computers. Most application scientists want to focus on the sciences and spend a minimum amount of time learning new tools or adopting new techniques to monitor and analyze their simulation data. The challenge eSimMon, of our web-based system is to decrease or eliminate some of the hurdles on the scientists path to scientific discovery, and allow these collaborations to flourish.

  10. Gradient instabilities of electromagnetic waves in Hall thruster plasma

    SciTech Connect (OSTI)

    Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)

    2013-04-15T23:59:59.000Z

    This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.

  11. Optimization Online - Using Simplex Gradients of Nonsmooth ...

    E-Print Network [OSTI]

    A. L. Custódio

    2006-10-27T23:59:59.000Z

    Oct 27, 2006 ... Using Simplex Gradients of Nonsmooth Functions in Direct Search Methods. A. L. Custódio (alcustodio ***at*** fct.unl.pt) J. E. Dennis (dennis ...

  12. Optimization Online - A Nonlinear Conjugate Gradient Algorithm ...

    E-Print Network [OSTI]

    Yu-Hong Dai

    2011-06-28T23:59:59.000Z

    Jun 28, 2011 ... Abstract: In this paper, we seek the conjugate gradient direction closest to the direction of the scaled memoryless BFGS method and propose a ...

  13. A GLOBALLY CONVERGENT MODIFIED CONJUGATE-GRADIENT ...

    E-Print Network [OSTI]

    2009-10-01T23:59:59.000Z

    gradient algorithms which implements this strategy in a robust and efficient way. ... Both begin with a second-order Taylor expansion modeling changes in f(xk) ...

  14. Optimization of synchronization in gradient clustered networks

    E-Print Network [OSTI]

    Xingang Wang; Liang Huang; Ying-Cheng Lai; Choy Heng Lai

    2007-11-23T23:59:59.000Z

    We consider complex clustered networks with a gradient structure, where sizes of the clusters are distributed unevenly. Such networks describe more closely actual networks in biophysical systems and in technological applications than previous models. Theoretical analysis predicts that the network synchronizability can be optimized by the strength of the gradient field but only when the gradient field points from large to small clusters. A remarkable finding is that, if the gradient field is sufficiently strong, synchronizability of the network is mainly determined by the properties of the subnetworks in the two largest clusters. These results are verified by numerical eigenvalue analysis and by direct simulation of synchronization dynamics on coupled-oscillator networks.

  15. Gearbox Reliability Collaborative Update (Presentation)

    SciTech Connect (OSTI)

    Sheng, S.

    2013-10-01T23:59:59.000Z

    This presentation was given at the Sandia Reliability Workshop in August 2013 and provides information on current statistics, a status update, next steps, and other reliability research and development activities related to the Gearbox Reliability Collaborative.

  16. Musicpainter : a collaborative composing environment

    E-Print Network [OSTI]

    Li, Wu-Hsi

    2008-01-01T23:59:59.000Z

    This thesis presents the design and implementation of Musicpainter, a networked graphical composing environment that encourages sharing and collaboration within the composing process. Instead of building a computer-assisted ...

  17. Coordination and Efficiency in Decentralized Collaboration

    E-Print Network [OSTI]

    Romero, Daniel M; Kleinberg, Jon

    2015-01-01T23:59:59.000Z

    Environments for decentralized on-line collaboration are now widespread on the Web, underpinning open-source efforts, knowledge creation sites including Wikipedia, and other experiments in joint production. When a distributed group works together in such a setting, the mechanisms they use for coordination can play an important role in the effectiveness of the group's performance. Here we consider the trade-offs inherent in coordination in these on-line settings, balancing the benefits to collaboration with the cost in effort that could be spent in other ways. We consider two diverse domains that each contain a wide range of collaborations taking place simultaneously -- Wikipedia and GitHub -- allowing us to study how coordination varies across different projects. We analyze trade-offs in coordination along two main dimensions, finding similar effects in both our domains of study: first we show that, in aggregate, high-status projects on these sites manage the coordination trade-off at a different level than t...

  18. Using Usage Information in Collaborative Information Environments

    E-Print Network [OSTI]

    Chalmers, M.; Position paper, Proceedings of the Collaborative Virtual Environments Workshop: CVE96 (Nottingham University) [More Details

    Chalmers,M. Position paper, Proceedings of the Collaborative Virtual Environments Workshop: CVE96 (Nottingham University)

  19. Approximate error conjugation gradient minimization methods

    DOE Patents [OSTI]

    Kallman, Jeffrey S

    2013-05-21T23:59:59.000Z

    In one embodiment, a method includes selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, calculating an approximate error using the subset of rays, and calculating a minimum in a conjugate gradient direction based on the approximate error. In another embodiment, a system includes a processor for executing logic, logic for selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, logic for calculating an approximate error using the subset of rays, and logic for calculating a minimum in a conjugate gradient direction based on the approximate error. In other embodiments, computer program products, methods, and systems are described capable of using approximate error in constrained conjugate gradient minimization problems.

  20. Gradient Improvement by Removal of Identified Local Defects

    SciTech Connect (OSTI)

    R.L. Geng, W.A. Clemens, C.A. Cooper, H. Hayano, K. Watanabe

    2011-07-01T23:59:59.000Z

    Recent experience of ILC cavity processing and testing at Jefferson Lab has shown that some 9-cell cavities are quench limited at a gradient in the range of 15-25 MV/m. Further studies reveal that these quench limits are often correlated with sub-mm sized and highly localized geometrical defects at or near the equator weld. There are increasing evidence to show that these genetic defects have their origin in the material or in the electron beam welding process (for example due to weld irregularities or splatters on the RF surface and welding porosity underneath the surface). A local defect removal method has been proposed at Jefferson Lab by locally re-melting the niobium material. Several 1-cell cavities with known local defects have been treated by using the JLab local e-beam re-melting method, resulting in gradient and Q0 improvement. We also sent 9-cell cavities with known gradient limiting local defects to KEK for local grinding and to FNAL for global mechanical polishing. We report on the results of gradient improvements by removal of local defects in these cavities.

  1. Page 1 of 4 Call for Collaborative Project Proposals for

    E-Print Network [OSTI]

    Sokolowski, Marla

    to collaborate with talented university researchers and access unique and powerful high performance computing university talent to conduct research that drives innovation; · Leverage world class high performance computing platforms to simulate and solve real world challenges. This computational capability and access

  2. Results of temperature gradient and heat flow in Santiam Pass Area, Oregon, Volume 1

    SciTech Connect (OSTI)

    Cox, B.L.; Gardner, M.C.; Koenig, J.B.

    1981-08-01T23:59:59.000Z

    The conclusions of this report are: (1) There is a weakly defined thermal anomaly within the area examined by temperature-gradient holes in the Santiam Pass area. This is a relict anomaly showing differences in permeability between the High Cascades and Western Cascades areas, more than a fundamental difference in shallow crustal temperatures. (2) The anomaly as defined by the 60 F isotherms at 400 feet follows a north-south trend immediately westward of the Cascade axis in the boundary region. It is clear that all holes spudded into High Cascades rocks result in isothermal and reversal gradients. Holes spudded in Western Cascades rocks result in positive gradients. (3) Cold groundwater flow influences and masks temperature gradients in the High Cascades to a depth of at least 700 feet, especially eastward from the major north-south trending faults. Pleistocene and Holocene rocks are very permeable aquifers. (4) Shallow gradient drilling in the lowlands westward of the faults provides more interpretable information than shallow drilling in the cold-water recharge zones. Topographic and climatological effects can be filtered out of the temperature gradient results. (5) The thermal anomaly seems to have 2 centers: one in the Belknap-Foley area, and one northward in the Sand Mountain area. The anomalies may or may not be connected along a north-south trend. (6) A geothermal effect is seen in holes downslope of the Western-High Cascade boundary. Mixing with cold waters is a powerful influence on temperature gradient data. (7) The temperature-gradient program has not yet examined and defined the geothermal resources potential of the area eastward of the Western Cascades-High Cascades boundary. Holes to 1500-2000 feet in depth are required to penetrate the high permeability-cold groundwater regime. (8) Drilling conditions are unfavorable. There are very few accessible level drill sites. Seasonal access problems and environmental restrictions together with frequent lost circulation results in very high costs per foot drilled.

  3. Collaborative University Research Education | 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 Office511041clothAdvanced Materials Advanced. C o w l i tCollaboration March 16, 2010 During theCollaborative

  4. Measurement of thermodynamics using gradient flow

    E-Print Network [OSTI]

    Masakiyo Kitazawa; Masayuki Asakawa; Tetsuo Hatsuda; Takumi Iritani; Etsuko Itou; Hiroshi Suzuki

    2014-12-15T23:59:59.000Z

    We analyze bulk thermodynamics and correlation functions of the energy-momentum tensor in pure Yang-Mills gauge theory using the energy-momentum tensor defined by the gradient flow and small flow time expansion. Our results on thermodynamic observables are consistent with those obtained by the conventional integral method. The analysis of the correlation function of total energy supports the energy conservation. It is also addressed that these analyses with gradient flow require less statistics compared with the previous methods. All these results suggest that the energy-momentum tensor can be successfully defined and observed on the lattice with moderate numerical costs with the gradient flow.

  5. Time changes in gradient and observed winds 

    E-Print Network [OSTI]

    Carlson, Ronald Dale

    1972-01-01T23:59:59.000Z

    TIME CHANGES IN GRADIENT AND OBSERVED WINDS A Thesis by RONALD DALE CARLSON Submitted to the Graduate College of Texas A&M University in partial fulfillm=n of the requirement for the degree of MASTER OF SCIENCE MAY 1972 Major Subject...: Meteorology TIME CHANGES IN GRADIENT AND OBSERVED WINDS A Thesis by RONALD D. CARLSON Approved as to style and content by: (Chairman of Co , ee) (Member) (Member) May 1972 ABSTRACT Time Changes in Gradient and Observed Winds. (May 1972) Ronald Dale...

  6. The ISO Galactic Metallicity Gradient Revisited

    E-Print Network [OSTI]

    Uriel Giveon; Christophe Morisset; Amiel Sternberg

    2002-07-22T23:59:59.000Z

    Two independent groups (Giveon et al. 2002; Martin-Hernandez et al. 2002) have recently investigated the Galactic metallicity gradient as probed by ISO observations of mid-infrared emission lines from HII regions. We show that the different gradients inferred by the two groups are due to differing source selection and differing extinction corrections. We show that both data sets in fact provide consistent results if identical assumptions are made in the analysis. We present a consistent set of gradients in which we account for extinction and variation in electron temperature across the disk.

  7. THE MULTIGRID PRECONDITIONED CONJUGATE GRADIENT METHOD Osamu Tatebe

    E-Print Network [OSTI]

    THE MULTIGRID PRECONDITIONED CONJUGATE GRADIENT METHOD Osamu Tatebe Department of Information Science University of Tokyo Tokyo, JAPAN SUMMARY A multigrid preconditioned conjugate gradient method iterations and the multigrid preconditioner is a desirable preconditioner of the conjugate gradient method. 1

  8. Program predicts two-phase pressure gradients

    SciTech Connect (OSTI)

    Jacks, D.C.; Hill, A.D.

    1983-11-18T23:59:59.000Z

    The calculator program discussed, ORK, was designed for the HP-41CV hand-held calculator and uses the Orkiszewski correlation for predicting 2-phase pressure gradients in vertical tubulars. Accurate predictions of pressure gradients in flowing and gas lift wells over a wide range of well conditions can be obtained with this method, which was developed based on data from 148 wells. The correlation is one of the best generalized 2-phase pressure gradient prediction methods developed to date for vertical flow. It is unique in that hold-up is derived from observed physical phenomena, and the pressure gradient is related to the geometrical distribution of the liquid and gas phase (flow regime).

  9. Collaboration Do More with MURR

    E-Print Network [OSTI]

    Noble, James S.

    radiopharmaceutical R&D and collaborations with academia and industry, and MURR continues to supply key medical isotopes throughout the earth: · CeretecTM (with Tc-99m), a diagnostic used to evaluate cerebral blood flow in patients and label white blood cells to identify infection, was developed at MU · Quadramet® (with Sm-153

  10. DISTRIBUTED AND COLLABORATIVE SYNTHETIC ENVIRONMENTS

    E-Print Network [OSTI]

    Texas at Austin, University of

    1 DISTRIBUTED AND COLLABORATIVE SYNTHETIC ENVIRONMENTS Chandrajit L. Bajaj and Fausto Bernardini with synthetic environments1,2,3,4,5,6 . A synthetic environment system is generally characterized and the synthetic environment generated by the computer. Several degrees of immersion are possible, ranging from

  11. A globally convergent modified conjugate-gradient line-search ...

    E-Print Network [OSTI]

    Wenwen Zhou

    2009-09-23T23:59:59.000Z

    Sep 23, 2009 ... Further, we provide a new variant of modified conjugate gradient algorithms ... optimization, trust region methods, conjugate gradient method.

  12. An inexact accelerated proximal gradient method for large scale ...

    E-Print Network [OSTI]

    2011-09-09T23:59:59.000Z

    projected gradient method, and usually has good practical performance on .... conditioned, the conjugate gradient (CG) method would have great difficulty in ...

  13. On the regularizing behavior of recent gradient methods in the ...

    E-Print Network [OSTI]

    Roberta De Asmundis

    2014-06-14T23:59:59.000Z

    Jun 14, 2014 ... On the regularizing behavior of recent gradient methods in the ... can be competitive with the Conjugate Gradient (CG) method, since they are ...

  14. a perry descent conjugate gradient method with restricted spectrum ...

    E-Print Network [OSTI]

    2011-05-09T23:59:59.000Z

    A new nonlinear conjugate gradient method, based on Perry's ... Key words and phrases. large scale optimization, conjugate gradient method, descent property ...

  15. Comparative systems biology across an evolutionary gradient within...

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

    systems biology across an evolutionary gradient within the Shewanella genus . Comparative systems biology across an evolutionary gradient within the Shewanella genus . Abstract: To...

  16. Aspen Code Development Collaboration

    SciTech Connect (OSTI)

    none,; Cherry, Robert S. [INL] INL; Richard, Boardman D. [INL] INL

    2013-10-03T23:59:59.000Z

    Wyoming has a wealth of primary energy resources in the forms of coal, natural gas, wind, uranium, and oil shale. Most of Wyoming?s coal and gas resources are exported from the state in unprocessed form rather than as refined higher value products. Wyoming?s leadership recognizes the opportunity to broaden the state?s economic base energy resources to make value-added products such as synthetic vehicle fuels and commodity chemicals. Producing these higher value products in an environmentally responsible manner can benefit from the use of clean energy technologies including Wyoming?s abundant wind energy and nuclear energy such as new generation small modular reactors including the high temperature gas-cooled reactors.

  17. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, Richard M. (Livermore, CA); Makowiecki, Daniel M. (Livermore, CA); Skulina, Kenneth M. (Livermore, CA)

    1995-01-01T23:59:59.000Z

    A process for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments m the soft x-ray region.

  18. Fabrication process for a gradient index x-ray lens

    DOE Patents [OSTI]

    Bionta, R.M.; Makowiecki, D.M.; Skulina, K.M.

    1995-01-17T23:59:59.000Z

    A process is disclosed for fabricating high efficiency x-ray lenses that operate in the 0.5-4.0 keV region suitable for use in biological imaging, surface science, and x-ray lithography of integrated circuits. The gradient index x-ray optics fabrication process broadly involves co-sputtering multi-layers of film on a wire, followed by slicing and mounting on block, and then ion beam thinning to a thickness determined by periodic testing for efficiency. The process enables the fabrication of transmissive gradient index x-ray optics for the 0.5-4.0 keV energy range. This process allows the fabrication of optical elements for the next generation of imaging and x-ray lithography instruments in the soft x-ray region. 13 figures.

  19. Enhancing distributed collaboration using sociometric feedback

    E-Print Network [OSTI]

    Kim, Taemie Jung

    2011-01-01T23:59:59.000Z

    Distributed collaboration is often more challenging than co-located collaboration as many of the social signals become lost in computer-mediated communication. I propose a system that improves the performance of distributed ...

  20. Discourse models for collaboratively edited corpora

    E-Print Network [OSTI]

    Chen, Erdong, S.M. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    This thesis focuses on computational discourse models for collaboratively edited corpora. Due to the exponential growth rate and significant stylistic and content variations of collaboratively edited corpora, models based ...

  1. Collaborative Firewalling in Wireless Networks Mahmoud Taghizadeh

    E-Print Network [OSTI]

    Liu, Alex X.

    Collaborative Firewalling in Wireless Networks Mahmoud Taghizadeh Department of ECE Michigan State elements to enforce access policies in computer networks. Open network architecture, shared wireless medium for wireless networks in which nodes collaboratively perform packet filtering to address resource squandering

  2. Collaborating With Utilities on Residential Energy Efficiency...

    Office of Environmental Management (EM)

    on Residential Energy Efficiency Better Buildings Residential Network Program Sustainability Peer Exchange Call Series: Collaborating With Utilities on Residential Energy...

  3. California Commissioning Collaborative: 2007 Program Plan

    E-Print Network [OSTI]

    Parks, J.

    2007-01-01T23:59:59.000Z

    California Commissioning Collaborative: 2007 Program Plan Presented by: Jim Parks, Chair CCC Board of Directors November 1, 2007 © California Commissioning Collaborative © California Commissioning Collaborative Mission and Organization • Improve... building and system performance by developing and promoting viable building commissioning practices in California – Make commissioning standard practice • Organized in 2000; non-profit status in 2004 • Board of Directors: utilities, state and federal...

  4. Effective Collaboration and Consistency Management in Business Process Modeling

    E-Print Network [OSTI]

    Czarnecki, Krzysztof

    Effective Collaboration and Consistency Management in Business Process Modeling Co-Chairs: Moises they are lost. Business Process Modeling (BPM) is a promising approach to enable agility in business process of experts. Business analysts gather requirements and create high-level process models. Solution architects

  5. Gearbox Reliability Collaborative Bearing Calibration

    SciTech Connect (OSTI)

    van Dam, J.

    2011-10-01T23:59:59.000Z

    NREL has initiated the Gearbox Reliability Collaborative (GRC) to investigate the root cause of the low wind turbine gearbox reliability. The GRC follows a multi-pronged approach based on a collaborative of manufacturers, owners, researchers and consultants. The project combines analysis, field testing, dynamometer testing, condition monitoring, and the development and population of a gearbox failure database. At the core of the project are two 750kW gearboxes that have been redesigned and rebuilt so that they are representative of the multi-megawatt gearbox topology currently used in the industry. These gearboxes are heavily instrumented and are tested in the field and on the dynamometer. This report discusses the bearing calibrations of the gearboxes.

  6. Comparative analysis of collaboration networks

    SciTech Connect (OSTI)

    Progulova, Tatiana; Gadjiev, Bahruz [International University for Nature, Society and Man, 19 Universitetskaya Street, Dubna, 141980 (Russian Federation)

    2011-03-14T23:59:59.000Z

    In this paper we carry out a comparative analysis of the word network as the collaboration network based on the novel by M. Bulgakov 'Master and Margarita', the synonym network of the Russian language as well as the Russian movie actor network. We have constructed one-mode projections of these networks, defined degree distributions for them and have calculated main characteristics. In the paper a generation algorithm of collaboration networks has been offered which allows one to generate networks statistically equivalent to the studied ones. It lets us reveal a structural correlation between word network, synonym network and movie actor network. We show that the degree distributions of all analyzable networks are described by the distribution of q-type.

  7. The QuarkNet/Grid collaborative learning e-lab

    SciTech Connect (OSTI)

    Bardeen, Marjorie; Gilbert, Eric; Jordan, Thomas; Nepywoda, Paul; Quigg, Elizabeth; /Fermilab; Wilde, Mike; /Argonne; Zhao, Yong; /Chicago U.

    2004-12-01T23:59:59.000Z

    We describe a case study that uses grid computing techniques to support the collaborative learning of high school students investigating cosmic rays. Students gather and upload science data to our e-Lab portal. They explore those data using techniques from the GriPhyN collaboration. These techniques include virtual data transformations, workflows, metadata cataloging and indexing, data product provenance and persistence, as well as job planners. Students use web browsers and a custom interface that extends the GriPhyN Chiron portal to perform all of these tasks. They share results in the form of online posters and ask each other questions in this asynchronous environment. Students can discover and extend the research of other students, modeling the processes of modern large-scale scientific collaborations. Also, the e-Lab portal provides tools for teachers to guide student work throughout an investigation.

  8. TOWARDS STOCHASTIC CONJUGATE GRADIENT METHODS Nicol N. Schraudolph Thore Graepel

    E-Print Network [OSTI]

    Schraudolph, Nicol N.

    TOWARDS STOCHASTIC CONJUGATE GRADIENT METHODS Nicol N. Schraudolph Thore Graepel schraudo of conjugate gradients provides a very effective way to optimize large, deterministic systems by gradient de. Here we explore a number of ways to adopt ideas from conjugate gradient in the stochastic setting

  9. Relationship between gradient and EM steps in latent variable models.

    E-Print Network [OSTI]

    Roweis, Sam

    includes random search, standard gradient­based algorithms, line search methods such as conjugate gradient to to first order method operat­ ing on the gradient of a locally reshaped likelihood function. DirectRelationship between gradient and EM steps in latent variable models. Ruslan Salakhutdinov Sam

  10. 11 SOME PROPERTIES OF A NEW CONJUGATE GRADIENT METHOD

    E-Print Network [OSTI]

    Yuan, Ya-xiang

    11 SOME PROPERTIES OF A NEW CONJUGATE GRADIENT METHOD Y. H. Dai and Y. Yuan State Key Laboratory@cc.ac.cn Abstract: It is proved that the new conjugate gradient method proposed by Dai and Yuan 5] produces problem minf(x) x 2 Rn (1.1) where f is smooth and its gradient g is available. Conjugate gradient methods

  11. Relationship between gradient and EM steps in latent variable models.

    E-Print Network [OSTI]

    Roweis, Sam

    includes random search, standard gradient-based algorithms, line search methods such as conjugate gradient to to first order method operat- ing on the gradient of a locally reshaped likelihood function. DirectRelationship between gradient and EM steps in latent variable models. Ruslan Salakhutdinov Sam

  12. Advanced engineering environment collaboration project.

    SciTech Connect (OSTI)

    Lamph, Jane Ann; Pomplun, Alan R.; Kiba, Grant W.; Dutra, Edward G.; Dankiewicz, Robert J.; Marburger, Scot J.

    2008-12-01T23:59:59.000Z

    The Advanced Engineering Environment (AEE) is a model for an engineering design and communications system that will enhance project collaboration throughout the nuclear weapons complex (NWC). Sandia National Laboratories and Parametric Technology Corporation (PTC) worked together on a prototype project to evaluate the suitability of a portion of PTC's Windchill 9.0 suite of data management, design and collaboration tools as the basis for an AEE. The AEE project team implemented Windchill 9.0 development servers in both classified and unclassified domains and used them to test and evaluate the Windchill tool suite relative to the needs of the NWC using weapons project use cases. A primary deliverable was the development of a new real time collaborative desktop design and engineering process using PDMLink (data management tool), Pro/Engineer (mechanical computer aided design tool) and ProductView Lite (visualization tool). Additional project activities included evaluations of PTC's electrical computer aided design, visualization, and engineering calculations applications. This report documents the AEE project work to share information and lessons learned with other NWC sites. It also provides PTC with recommendations for improving their products for NWC applications.

  13. Critical gradient formula for toroidal electron temperature gradient modes F. Jenko, W. Dorland,a)

    E-Print Network [OSTI]

    Hammett, Greg

    Critical gradient formula for toroidal electron temperature gradient modes F. Jenko, W. Dorland and edge plasmas are presented. An algebraic formula for the threshold of the linear instability is derived formula. We discuss the results with respect to previous analytical results and to experimental

  14. Electric field gradient, generalized Sternheimer shieldings and electric field gradient polarizabilities by multiconfigurational SCF response

    E-Print Network [OSTI]

    Helgaker, Trygve

    Electric field gradient, generalized Sternheimer shieldings and electric field gradient at the nuclei, the generalized Sternheimer shielding constants and the EFG electric dipole polarizabilities discussed by Egstro¨m and co-workers4 and recently in a more general way by Fowler and co-workers.5

  15. Gradient flow and scale setting on MILC HISQ ensembles

    E-Print Network [OSTI]

    Bazavov, A; Brown, N; DeTar, C; Foley, J; Gottlieb, Steven; Heller, U M; Komijani, J; Laiho, J; Levkova, L; Sugar, R L; Toussaint, D; Van de Water, R S

    2015-01-01T23:59:59.000Z

    We report on a scale determination with gradient-flow techniques on the $N_f=2+1+1$ HISQ ensembles generated by the MILC collaboration. The ensembles include four lattice spacings, ranging from approximately 0.15 to 0.06 fm, and both physical and unphysical values of the quark masses. The scales $\\sqrt{t_0}/a$ and $w_0/a$ and their tree-level improvements, $\\sqrt{t_{0,{\\rm imp}}}$ and $w_{0,{\\rm imp}}$, are computed on each ensemble using Symanzik flow and the cloverleaf definition of the energy density $E$. Using a combination of continuum chiral perturbation theory and a Taylor-series ansatz for the lattice-spacing and strong-coupling dependence, the results are simultaneously extrapolated to the continuum and interpolated to physical quark masses. We determine the scales $\\sqrt{t_0} = 0.1416({}_{-5}^{+8})$ fm and $w_0 = 0.1717({}_{-11}^{+12})$ fm, where the errors are sums, in quadrature, of statistical and all systematic errors. The precision of $w_0$ and $\\sqrt{t_0}$ is comparable to or more precise than...

  16. Conjugate gradient algorithms using multiple recursions

    SciTech Connect (OSTI)

    Barth, T.; Manteuffel, T.

    1996-12-31T23:59:59.000Z

    Much is already known about when a conjugate gradient method can be implemented with short recursions for the direction vectors. The work done in 1984 by Faber and Manteuffel gave necessary and sufficient conditions on the iteration matrix A, in order for a conjugate gradient method to be implemented with a single recursion of a certain form. However, this form does not take into account all possible recursions. This became evident when Jagels and Reichel used an algorithm of Gragg for unitary matrices to demonstrate that the class of matrices for which a practical conjugate gradient algorithm exists can be extended to include unitary and shifted unitary matrices. The implementation uses short double recursions for the direction vectors. This motivates the study of multiple recursion algorithms.

  17. Collaboration

    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 742EnergyOnItem NotEnergy,ARMForms AboutRESEARCH CAPABILITIES ThematerialsAbout »

  18. Time changes in gradient and observed winds

    E-Print Network [OSTI]

    Carlson, Ronald Dale

    1972-01-01T23:59:59.000Z

    - cal purposes, represents the changes in the components of the gradient wind speed, as calculated from Eqs. (9) and (10). Equations (9) and (10) were solved by the use of finite dif- ference methods. Due to the long incremental time steps, 3 to 12... hours, the changes in the components of the gradient wind speed obtained numerically from Eqs. (9) and (10) may differ slightly from the changes observed due to the numerical techniques employed. How- ever, the patterns obtained by the two methods...

  19. The gradient flow running coupling with twisted boundary conditions

    E-Print Network [OSTI]

    A. Ramos

    2014-09-04T23:59:59.000Z

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

  20. ALS Collaborative Postdoctoral Fellowship Program

    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(ANL-IN-03-032)8Li (59AJ76) (See the EnergyTAMANG,ALSCollaborativeCollaborative

  1. Efficient Gradient Computation for Dynamical B. Sengupta

    E-Print Network [OSTI]

    Penny, Will

    descriptive length, variational free energy, etc. Generally, optimisation rests on evaluating the localEfficient Gradient Computation for Dynamical Models B. Sengupta , K.J. Friston and W.D. Penny of thousands of neurons using fMRI. Data assimilation involves inverting a generative model that can not only

  2. Multi-gradient drilling method and system

    DOE Patents [OSTI]

    Maurer, William C. (Houston, TX); Medley, Jr., George H. (Spring, TX); McDonald, William J. (Houston, TX)

    2003-01-01T23:59:59.000Z

    A multi-gradient system for drilling a well bore from a surface location into a seabed includes an injector for injecting buoyant substantially incompressible articles into a column of drilling fluid associated with the well bore. Preferably, the substantially incompressible articles comprises hollow substantially spherical bodies.

  3. Application of Gradient Expansion to Inflationary Universe

    E-Print Network [OSTI]

    Yasusada Nambu; Atsushi Taruya

    1994-11-03T23:59:59.000Z

    Using the long wave perturbation scheme(gradient expansion), the effect of inhomogeneity on the inflationary phase is investigated. We solved the perturbation equation of which source term comes from inhomogeneity of a scalar field and a seed metric. The result indicates that sub-horizon scale inhomogeneity strongly affects the onset of inflation.

  4. Gradient Clock Synchronization in Wireless Sensor Networks

    E-Print Network [OSTI]

    Gradient Clock Synchronization in Wireless Sensor Networks Philipp Sommer Computer Engineering- olution. Without doubt, time is a first-class citizen in wireless sensor networks. Without accurate time if the nodes in the wireless sensor network manage to have an adequate agreement of time. Indeed

  5. Universal Microfluidic Gradient Generator Daniel Irimia1

    E-Print Network [OSTI]

    Geba, Dan-Andrei

    Universal Microfluidic Gradient Generator Daniel Irimia1 , Dan A Geba2 , Mehmet Toner1 1 Bio, Building 114, 16th St, Charlestown, MA 02129. Email: mtoner@hms.harvard.edu Keywords: microfluidics cells in vitro. While microfluidic devices have shown unmatched capability in generating linear stable

  6. Gradient zone-boundary control in salt-gradient solar ponds

    DOE Patents [OSTI]

    Hull, J.R.

    1982-09-29T23:59:59.000Z

    A method and apparatus for suppressing zone boundary migration in a salt gradient solar pond includes extending perforated membranes across the pond at the boundaries, between the convective and non-convective zones, the perforations being small enough in size to prevent individual turbulence disturbances from penetrating the hole, but being large enough to allow easy molecular diffusion of salt thereby preventing the formation of convective zones in the gradient layer. The total area of the perforations is a sizeable fraction of the membrane area to allow sufficient salt diffusion while preventing turbulent entrainment into the gradient zone.

  7. Migration of the European sea bass Cefas have been collaborating with IFREMER scientists and the Breton

    E-Print Network [OSTI]

    Migration of the European sea bass Cefas have been collaborating with IFREMER scientists bass, Dicentrarchus labrax. Although a popular and important catch for both commercial and recreational fishermen, relatively little is known about the behaviour of this highly migratory fish

  8. Stellar Population Gradients in Bulges along the Hubble Sequence: II. Relations with Galaxy Properties

    E-Print Network [OSTI]

    P. Jablonka; J. Gorgas; P. Goudfrooij

    2007-07-04T23:59:59.000Z

    We present the analysis of the radial gradients of stellar absorption lines in a sample of 32 bulges of edge-on spiral galaxies, spanning nearly the full Hubble sequence (from S0 to Sc types), and a large range of velocity dispersion (from about 60 to 300 km/s). Different diagnostics such as index-index, gradient-gradient diagrams, and simple stellar population models are used to tackle the origin of the variation of the bulge stellar population. We find that the vast majority of bulges show older age, lower metallicity and higher [alpha/Fe] in their outer regions than in their central parts. The radial gradients in [Fe/H] are 2 to 3 times larger than in Log(age). The relation between gradient and bulge velocity dispersion is interpreted as a gradual build up of the gradient mean values and their dispersions from high to low velocity dispersion, rather than a pure correlation. The bulge effective radii and the Hubble type of the parent galaxies seem to play a more minor role in causing the observed spatial distributions. At a given velocity dispersion, bulges and ellipticals share common properties.

  9. Outreach and Collaboration Program Status and Accomplishments...

    Office of Environmental Management (EM)

    2008-2009 Outreach and Collaboration has helped HSS expand the DOE's sphere of communication and influence through broad-based dialogues, cultivating productive interagency...

  10. Equal Employment Opportunity: Collaborating for Mission Success

    National Nuclear Security Administration (NNSA)

    2012 Equal Employment Opportunity: Collaborating for Mission Success U.S. DEPARTMENT OF ENERGY National Nuclear Security Administration 2012 EEO Report of Accomplishment 2012...

  11. Environmental Justice Interagency Collaborative Newsletter Volume 1

    Broader source: Energy.gov [DOE]

    The inaugural edition of the Environmental Justice Interagency Collaborative Newsletter is one of many opportunities the agencies are utilizing to share information and to communicate the various...

  12. EEO Complaint Equal Employment Opportunity: Collaborating for...

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

    r EEO Complaint Equal Employment Opportunity: Collaborating for Mission Success Things to Consider Before you Decide to File.... BURDEN OF PROOF IN THE EEO COMPLAINT PROCESS Who...

  13. Advanced Collaborative Emissions Study (ACES) NETL Agreement...

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

    NETL Agreement 13919 Advanced Collaborative Emissions Study (ACES) NETL Agreement 13919 Presentation from the U.S. DOE Office of Vehicle Technologies "Mega" Merit Review 2008 on...

  14. Geothermal potential of West-Central New Mexico from geochemical and thermal gradient data

    SciTech Connect (OSTI)

    Levitte, D.; Gambill, D.T.

    1980-11-01T23:59:59.000Z

    To study the low temperature and Hot Dry Rock (HDR) geothermal potential of west-central New Mexico, 46 water samples were collected and geothermal gradient measurements were made in 29 wells. Water chemistry data indicate that all the samples collected are meteoric waters. High temperatures of samples taken from wells between Gallup and Tohatchi indicate these wells may derive water from a warm aquifer below the depth of the wells. The chemistries of the samples farther south on the Zuni Indian reservation suggest these waters are not circulating below 600 m of the surface. Geothermometry calculations support the conclusion that the waters sampled are meteoric. The geothermometry also indicates that the deep reservoir between Gallup and Tohatchi may be greater than 60/sup 0/C. Thermal gradient data indicate an area of high gradient on the Zuni Indian Reservation with a measured maximum of 67/sup 0/C/km between 181 m and 284 m. This high probably is not hydrologically controlled. The maximum gradients in the study area are 76/sup 0/C/km and 138/sup 0/C/km, measured just east of Springerville, Arizona. These gradients are undoubtedly controlled by circulating water, possibly heated by a magmatic source at depth and circulating back to the surface.

  15. FIRST MEASUREMENT OF PRESSURE GRADIENT-DRIVEN CURRENTS IN TOKAMAK EDGE PLASMAS

    SciTech Connect (OSTI)

    THOMAS DM; LEONARD AW; LAO LL; OSBORNE TH; MUELLER HW; FINKENTHAL DK

    2003-11-01T23:59:59.000Z

    Localized currents driven by pressure gradients play a pivotal role in the magnetohydrodynamic stability of toroidal plasma confinement devices. We have measured the currents generated in the edge of L- (low) and H- (high confinement) mode discharges on the DIII-D tokamak, utilizing the Zeeman effect in an injected lithium beam to obtain high resolution profiles of the poloidal magnetic field. We find current densities in excess of 1 MA/m{sup 2} in a 1 to 2 cm region near the peak of the edge pressure gradient. These values are sufficient to challenge edge stability theories based on specific current formation models.

  16. Fast quantum algorithm for numerical gradient estimation

    E-Print Network [OSTI]

    Stephen P. Jordan

    2005-01-02T23:59:59.000Z

    Given a blackbox for f, a smooth real scalar function of d real variables, one wants to estimate the gradient of f at a given point with n bits of precision. On a classical computer this requires a minimum of d+1 blackbox queries, whereas on a quantum computer it requires only one query regardless of d. The number of bits of precision to which f must be evaluated matches the classical requirement in the limit of large n.

  17. A Preconditioner for a Primal-Dual Newton Conjugate Gradients ...

    E-Print Network [OSTI]

    Kimon Fountoulakis

    2014-12-30T23:59:59.000Z

    Dec 30, 2014 ... A Preconditioner for a Primal-Dual Newton Conjugate Gradients Method for Compressed Sensing Problems.

  18. Optimization Online - Conjugate gradient methods based on secant ...

    E-Print Network [OSTI]

    Y Narushima

    2011-09-28T23:59:59.000Z

    Sep 28, 2011 ... Conjugate gradient methods based on secant conditions that generate descent search directions for unconstrained optimization.

  19. A three-term conjugate gradient method with sufficient descent ...

    E-Print Network [OSTI]

    2009-11-02T23:59:59.000Z

    Finally, some numerical results of the proposed method are given. keyword; Unconstrained optimization, three-term conjugate gradient method, sufficient.

  20. BASIC GEOPHYSICAL FLUID Lecture 3: Gradient winds, pressure

    E-Print Network [OSTI]

    Read, Peter L.

    cyclostrophic balance. 2 #12;Example of gradient-wind balance: Hurricane Andrew 3 #12;Examples of cyclostrophic

  1. Energy Gradient Theory of Hydrodynamic Instability

    E-Print Network [OSTI]

    Hua-Shu Dou

    2005-01-29T23:59:59.000Z

    A new universal theory for flow instability and turbulent transition is proposed in this study. Flow instability and turbulence transition have been challenging subjects for fluid dynamics for a century. The critical condition of turbulent transition from theory and experiments differs largely from each other for Poiseuille flows. In this paper, a new mechanism of flow instability and turbulence transition is presented for parallel shear flows and the energy gradient theory of hydrodynamic instability is proposed. It is stated that the total energy gradient in the transverse direction and that in the streamwise direction of the main flow dominate the disturbance amplification or decay. A new dimensionless parameter K for characterizing flow instability is proposed for wall bounded shear flows, which is expressed as the ratio of the energy gradients in the two directions. It is thought that flow instability should first occur at the position of Kmax which may be the most dangerous position. This speculation is confirmed by Nishioka et al's experimental data. Comparison with experimental data for plane Poiseuille flow and pipe Poiseuille flow indicates that the proposed idea is really valid. It is found that the turbulence transition takes place at a critical value of Kmax of about 385 for both plane Poiseuille flow and pipe Poiseuille flow, below which no turbulence will occur regardless the disturbance. More studies show that the theory is also valid for plane Couette flows and Taylor-Couette flows between concentric rotating cylinders.

  2. Unauthorized Collaboration on Facebook: Threats and Responses

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Unauthorized Collaboration on Facebook: Threats and Responses Recent events at FSU have uncovered and collaboration. The Problem: When students, faculty, and staff join Facebook using a valid FSU email address this and believe it is affiliated with or endorsed by Florida State University. Facebook also allows students

  3. Team Assembly Mechanisms Determine Collaboration Network

    E-Print Network [OSTI]

    Kuzmanovic, Aleksandar

    Team Assembly Mechanisms Determine Collaboration Network Structure and Team Performance Roger the mechanisms by which creative teams self-assemble determine the structure of these collaboration networks. We propose a model for the self-assembly of creative teams that has its basis in three parameters: team size

  4. Electronic collaboration across organizational borders in the

    E-Print Network [OSTI]

    Langseth, Helge

    Electronic collaboration across organizational borders in the health care sector Design:252 Printed by NTNU-trykk #12;i Electronic collaboration across organizational borders in the health care borders in the health care sector. I have studied this problem from a sociotechnical1 point of view

  5. July 21, 2011 SPC Collaborates with Haydenfilms

    E-Print Network [OSTI]

    Hardy, Christopher R.

    Exchange July 21, 2011 1 SPC Collaborates with Haydenfilms During the summer of 2011, the Software Productization Center (SPC) at Millersville University is collaborating with regional company Haydenfilms and prototype system to show potential customers and investors. The SPC at Millersville University, formed

  6. Evaluation of liquid lift approach to dual gradient

    E-Print Network [OSTI]

    Okafor, Ugochukwu Nnamdi

    2009-05-15T23:59:59.000Z

    ............................................... 4 2.2 Dual Gradient Drilling Method.............................................. 5 2.3 Methods of Achieving Dual Gradient Drilling ...................... 9 2.3.1 Subsea Mudlift Drilling... ................................................... 9 2.5 Schematic diagram of a modified subsea mudlift system .......................... 11 2.6 Hollow glass-spheres dual gradient drilling system................................... 13 2.7 A typical offshore drilling rig modified...

  7. Evaluation of liquid lift approach to dual gradient drilling

    E-Print Network [OSTI]

    Okafor, Ugochukwu Nnamdi

    2008-10-10T23:59:59.000Z

    ............................................... 4 2.2 Dual Gradient Drilling Method.............................................. 5 2.3 Methods of Achieving Dual Gradient Drilling ...................... 9 2.3.1 Subsea Mudlift Drilling... ................................................... 9 2.5 Schematic diagram of a modified subsea mudlift system .......................... 11 2.6 Hollow glass-spheres dual gradient drilling system................................... 13 2.7 A typical offshore drilling rig modified...

  8. USING SIMPLEX GRADIENTS OF NONSMOOTH FUNCTIONS IN DIRECT SEARCH METHODS

    E-Print Network [OSTI]

    Vicente, Luís Nunes

    USING SIMPLEX GRADIENTS OF NONSMOOTH FUNCTIONS IN DIRECT SEARCH METHODS A. L. CUST´ODIO , J. E by reordering the poll directions according to descent indicators built from simplex gradients. The purpose of this paper is twofold. First, we analyze the properties of simplex gradients of nonsmooth functions

  9. AN EXTENDED CLASS OF NONLINEAR CONJUGATE GRADIENT METHODS \\Lambda

    E-Print Network [OSTI]

    Yuan, Ya-xiang

    AN EXTENDED CLASS OF NONLINEAR CONJUGATE GRADIENT METHODS \\Lambda Y. H. Dai and Y. Yuan State Key 100080, P. R. China. Email: dyh,yyx@lsec.cc.ac.cn Abstract Conjugate gradient methods are very important be analyzed uniformly, conjugate gradient methods are often analyzed individually. Recently, Dai and Yuan

  10. AN AUGMENTED CONJUGATE GRADIENT METHOD FOR SOLVING CONSECUTIVE

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AN AUGMENTED CONJUGATE GRADIENT METHOD FOR SOLVING CONSECUTIVE SYMMETRIC POSITIVE DEFINITE LINEAR definite matrix A. The conjugate gradient method applied to the first system generates a Krylov subspace conjugate gradient method is then applied with a specific initial guess and initial descent direction

  11. CONVERGENCE PROPERTIES OF NONLINEAR CONJUGATE GRADIENT METHODS1

    E-Print Network [OSTI]

    Yuan, Ya-xiang

    CONVERGENCE PROPERTIES OF NONLINEAR CONJUGATE GRADIENT METHODS1 Yuhong Dai2 , Jiye Han3 , Guanghui contributions on convergence studies of conjugate gradient methods have been made by Gilbert and Nocedal [6 for ensuring the global convergence of conjugate gradient methods. This paper shows that the sufficient descent

  12. ON THE CONNECTION BETWEEN THE CONJUGATE GRADIENT METHOD AND

    E-Print Network [OSTI]

    Forsgren, Anders

    ON THE CONNECTION BETWEEN THE CONJUGATE GRADIENT METHOD AND QUASI-NEWTON METHODS ON QUADRATIC Royal Institute of Technology February 2013 Abstract It is well known that the conjugate gradient method gradient method. In the framework based on a sufficient condition to obtain mutually conjugate search

  13. Preconditioned Conjugate Gradient Methods for Three Dimensional Linear Elasticity

    E-Print Network [OSTI]

    Waterloo, University of

    Preconditioned Conjugate Gradient Methods for Three Dimensional Linear Elasticity by John Kenneth. A brief review is also made of stopping criteria for conjugate gradient solvers. One method based and tested with poor results. iv #12;Contents 1 Introduction 1 1.1 Preconditioned Conjugate Gradient Methods

  14. CG DESCENT, A CONJUGATE GRADIENT METHOD WITH GUARANTEED DESCENT

    E-Print Network [OSTI]

    Zhang, Hongchao

    CG DESCENT, A CONJUGATE GRADIENT METHOD WITH GUARANTEED DESCENT #3; WILLIAM W. HAGER y AND HONGCHAO are given. Key words. Conjugate gradient method, unconstrained optimization, convergence, line search, Wolfe nonlinear conjugate gradient method for solving an unconstrained optimization problem min ff(x) : x 2

  15. A conjugate gradient learning algorithm for recurrent neural networks

    E-Print Network [OSTI]

    Mak, Man-Wai

    ]. In particular, the conjugate gradient method is commonly used in training BP networks due to its speed1 A conjugate gradient learning algorithm for recurrent neural networks (Revised Version) Wing algorithm by incorporating conjugate gradient computation into its learning procedure. The resulting

  16. APPROXIMATE INVERSE PRECONDITIONING FOR THE CONJUGATE GRADIENT METHOD

    E-Print Network [OSTI]

    Tùma, Miroslav

    APPROXIMATE INVERSE PRECONDITIONING FOR THE CONJUGATE GRADIENT METHOD ON A VECTOR COMPUTER Michele definite matrix, by the preconditioned conjugate gradient method (PCG) (see, e.g., [4]). It is well of the conjugate gradient method reduces to computing a matrix­ vector product with G, an operation which offers

  17. Ducted kinetic Alfven waves in plasma with steep density gradients

    SciTech Connect (OSTI)

    Houshmandyar, Saeid [Solar Observatory Department, Prairie View A and M University, Prairie View, Texas 77446 (United States); Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States); Scime, Earl E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States)

    2011-11-15T23:59:59.000Z

    Given their high plasma density (n {approx} 10{sup 13} cm{sup -3}), it is theoretically possible to excite Alfven waves in a conventional, moderate length (L {approx} 2 m) helicon plasma source. However, helicon plasmas are decidedly inhomogeneous, having a steep radial density gradient, and typically have a significant background neutral pressure. The inhomogeneity introduces regions of kinetic and inertial Alfven wave propagation. Ion-neutral and electron-neutral collisions alter the Alfven wave dispersion characteristics. Here, we present the measurements of propagating kinetic Alfven waves in helium helicon plasma. The measured wave dispersion is well fit with a kinetic model that includes the effects of ion-neutral damping and that assumes the high density plasma core defines the radial extent of the wave propagation region. The measured wave amplitude versus plasma radius is consistent with the pile up of wave magnetic energy at the boundary between the kinetic and inertial regime regions.

  18. Illinois: High-Energy, Concentration-Gradient Cathode Material...

    Office of Environmental Management (EM)

    Project Overview Positive Impact Batteries for electric drive vehicles and renewable energy storage will reduce petroleum usage, improving energy security and reducing harmful...

  19. Fast global convergence of gradient methods for high-dimensional ...

    E-Print Network [OSTI]

    2012-08-24T23:59:59.000Z

    of the optimization error, measured in terms of the Euclidean norm ?t ? ?? between the current iterate ?t ...... [4] S. Becker, J. Bobin, and E. J. Candes. Nesta: a ...

  20. Developing new high energy gradient concentration cathode material |

    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 DataDepartment of Energy Your Density Isn't Your Destiny:Revised Finding of No53197E T A * S H I E LGeothermalEnergy Aa newState

  1. New High Energy Gradient Concentration Cathode Material | Department of

    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 DataDepartment of Energy Your Density Isn'tOrigin of Contamination in Many DevilsForum |EnergyNewEnergy Services

  2. New High Energy Gradient Concentration Cathode Material | Department of

    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 DataDepartment of Energy Your Density Isn'tOrigin of Contamination in Many DevilsForum |EnergyNewEnergy ServicesEnergy 1 DOE

  3. New High Energy Gradient Concentration Cathode Material | Department of

    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 DataDepartment of Energy Your Density Isn'tOrigin of Contamination in Many DevilsForum |EnergyNewEnergy ServicesEnergy 1

  4. 9519 biotite granodiorite reacted in a temperature gradient

    SciTech Connect (OSTI)

    Charles, R.W.; Bayhurst, G.K.

    1980-10-01T23:59:59.000Z

    A biotite granodiorite from the Fenton Hill Hot Dry Rock (HDR) geothermal system was reacted in a controlled temperature gradient with initially distilled water for 60d. Polished rock prisms were located in the gradient at 72, 119, 161, 209, 270, and 310/sup 0/C. Scanning electron microscope and microprobe analyses show the appearance of secondary phases: Ca-montmorillonite at 72/sup 0/C and 119/sup 0/C; zeolite, either stilbite or heulandite, at 161/sup 0/C; and another zeolite, thomsonite, at higher temperatures. Solution analyses show a steady state equilibrium exists between solution and overgrowths after about 2 weeks of reaction. The chemographic relations for the system are explored in some detail indicating the divariant assemblages may be placed in a reasonable sequence in intensive variable space. These relations predict high and low temperature effects not directly observed experimentally as well as relevant univariant equilibria. Solution chemistry indicates the Na-Ca-K geothermometer more adequately predicts temperature in this system than does the silica geothermometer.

  5. Research Councils UK Joint Vision For Collaborative Training

    E-Print Network [OSTI]

    Berzins, M.

    Research Councils UK Joint Vision For Collaborative Training Objectives: Research Council Collaborative Training will provide doctoral students with a first- rate, challenging research training organisations in the private, public and civil society sectors. Benefits to the student ­ Collaborative Training

  6. Collaborative Reverse Engineering Design Experiment Using PLM Solutions*

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Collaborative Reverse Engineering Design Experiment Using PLM Solutions* FREDERIC SEGONDS,1 NICOLAS Managament'' (PLM) concepts. Finally, we present some modifications in collaborative design courses for our of the design environment. Keywords: reverse engineering; education, PLM; collaborative design 1. Recent changes

  7. Towards Controlling the Acceptance Factors for a Collaborative Platform in

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Towards Controlling the Acceptance Factors for a Collaborative Platform in Engineering Design factor which are supposed to influence future users of a collaborative KM platform (Dimocode). At the end management systems (KMS) deployment. Keywords: acceptance factors, collaborative, platforms, engineering

  8. Capacitive mixing power production from salinity gradient energy enhanced through exoelectrogen-

    E-Print Network [OSTI]

    thermolytic solutions that can be used to capture waste heat energy as salinity gradient energy. Forced our expanding water and energy infrastructures across the globe, the development of sustainable dual energy generation and water treatment process is highly desirable. A combined capacitive mixing

  9. Final Report, CONTRIBUTIONS TO STUDIES OF CP VIOLATION AND HADRONIC PHYSICS WITH THE BABAR COLLABORATION

    SciTech Connect (OSTI)

    Brown, David Norvil [University of Louisville] [University of Louisville

    2013-07-25T23:59:59.000Z

    The University of Louisville High Energy Physics group has undertaken a long-term effort in understanding baryon production in elementary particle processes in the 10 GeV energy region. We have contributed significantly to the broad program of the BaBar Collaboration, particularly in support of computing, data visualization, and simulation. We report here on progress in the areas of service to the Collaboration and understanding of baryon production via measurement of inclusive hadronic particle spectra.

  10. Adjustable, rapidly switching microfluidic gradient generation using focused travelling surface acoustic waves

    SciTech Connect (OSTI)

    Destgeer, Ghulam; Im, Sunghyuk; Hang Ha, Byung; Ho Jung, Jin; Ahmad Ansari, Mubashshir; Jin Sung, Hyung, E-mail: hjsung@kaist.ac.kr [Department of Mechanical Engineering, KAIST, 291 Daejak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2014-01-13T23:59:59.000Z

    We demonstrate a simple device to generate chemical concentration gradients in a microfluidic channel using focused travelling surface acoustic waves (F-TSAW). A pair of curved interdigitated metal electrodes deposited on the surface of a piezoelectric (LiNbO{sub 3}) substrate disseminate high frequency sound waves when actuated by an alternating current source. The F-TSAW produces chaotic acoustic streaming flow upon its interaction with the fluid inside a microfluidic channel, which mixes confluent streams of chemicals in a controlled fashion for an adjustable and rapidly switching gradient generation.

  11. Correlation of Beam Parameters to Decelerating Gradient in the E-167 Plasma Wakefield Acceleration Experiment

    SciTech Connect (OSTI)

    Blumenfeld, I.; Berry, M.; Decker, F.-J.; Hogan, M.J.; Ischebeck, R.; Iverson, R.; Kirby, N.; Siemann, R.; Walz, D.; /SLAC; Clayton, C.E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA; Katsouleas, T.C.; Muggli, P.; Oz, E.; /Southern California U.

    2007-06-27T23:59:59.000Z

    Recent experiments at SLAC have shown that high gradient acceleration of electrons is achievable in meter scale plasmas [1,2]. Results from these experiments show that the wakefield is sensitive to parameters in the electron beam which drives it. In the experiment the bunch length and beam waist location were varied systematically at constant charge. Here we investigate the correlation of peak beam current to the decelerating gradient. Limits on the transformer ratio will also be discussed. The results are compared to simulation.

  12. FFranche-Comt EElectronique MMcanique TThermique et OOptique -Sciences et Technologies Brazil-France collaboration 2013

    E-Print Network [OSTI]

    Jeanjean, Louis

    -France collaboration 2013 TITLE (English) Imprecise computations for energy efficiency in high performance computing website (500 characters max, English) Reducing the energy consumption in high performance computing of computing systems: for high performance computing systems as clusters or grids as well as for embedded

  13. The gradient flow running coupling scheme

    E-Print Network [OSTI]

    Zoltan Fodor; Kieran Holland; Julius Kuti; Daniel Nogradi; Chik Him Wong

    2012-11-14T23:59:59.000Z

    The Yang-Mills gradient flow in finite volume is used to define a running coupling scheme. As our main result the discrete beta-function, or step scaling function, is calculated for scale change s=3/2 at several lattice spacings for SU(3) gauge theory coupled to N_f = 4 fundamental massless fermions. The continuum extrapolation is performed and agreement is found with the continuum perturbative results for small renormalized coupling. The case of SU(2) gauge group is briefly commented on.

  14. Steep Gradient Flume | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries Pvt LtdShawangunk,SoutheastSt.Steep Gradient Flume Jump to: navigation, search

  15. Government and Industry A Force for Collaboration at the Energy...

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

    Government and Industry A Force for Collaboration at the Energy Roadmap Update Workshop Government and Industry A Force for Collaboration at the Energy Roadmap Update Workshop...

  16. International Collaboration With a Case Study in Assessment of...

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

    Collaboration With a Case Study in Assessment of Worlds Supply of Lithium International Collaboration With a Case Study in Assessment of Worlds Supply of Lithium 2009 DOE...

  17. Advancing our Nuclear Collaboration with the Czech Republic ...

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

    our Nuclear Collaboration with the Czech Republic Advancing our Nuclear Collaboration with the Czech Republic September 28, 2011 - 5:36pm Addthis President Obama addresses a crowd...

  18. Council on Environmental Quality Collaboration in NEPA A Handbook...

    Energy Savers [EERE]

    Council on Environmental Quality Collaboration in NEPA A Handbook for NEPA Practitioners Council on Environmental Quality Collaboration in NEPA A Handbook for NEPA Practitioners...

  19. DOE and NRCan Agreement to Enhance Collaboration in Civilian...

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

    DOE and NRCan Agreement to Enhance Collaboration in Civilian Nuclear Energy Research and Development DOE and NRCan Agreement to Enhance Collaboration in Civilian Nuclear Energy...

  20. Phase 1 of the Advanced Collaborative Emissions Study (ACES)...

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

    1 of the Advanced Collaborative Emissions Study (ACES): Highlights of Project Finding Phase 1 of the Advanced Collaborative Emissions Study (ACES): Highlights of Project Finding...

  1. Collaborative Utility Task Force Partners with DOE to Develop...

    Energy Savers [EERE]

    Collaborative Utility Task Force Partners with DOE to Develop Cyber Security Requirements for Advanced Metering Infrastructure Collaborative Utility Task Force Partners with DOE to...

  2. DOE/EPRI 2013 Electricity Storage Handbook in Collaboration with...

    Energy Savers [EERE]

    EPRI 2013 Electricity Storage Handbook in Collaboration with NRECA (July 2013) DOEEPRI 2013 Electricity Storage Handbook in Collaboration with NRECA (July 2013) The Electricity...

  3. Federal Agencies Collaborate to Expedite Construction of Alaska...

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

    Collaborate to Expedite Construction of Alaska Natural Gas Pipeline Federal Agencies Collaborate to Expedite Construction of Alaska Natural Gas Pipeline June 29, 2006 - 2:44pm...

  4. DOE to Launch Collaborative Effort with Industry to Improve Natural...

    Energy Savers [EERE]

    DOE to Launch Collaborative Effort with Industry to Improve Natural Gas Systems DOE to Launch Collaborative Effort with Industry to Improve Natural Gas Systems July 30, 2014 -...

  5. Grid Interaction Tech Team, and International Smart Grid Collaboration...

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

    Team, and International Smart Grid Collaboration Grid Interaction Tech Team, and International Smart Grid Collaboration 2012 DOE Hydrogen and Fuel Cells Program and Vehicle...

  6. Electron transport and frozen concentration gradients in a mixed valent viologen molten salt

    SciTech Connect (OSTI)

    Terrill, R.H.; Hatazawa, Tsuyonobu; Murray, R.W. [Univ. of North Carolina, Chapel Hill, NC (United States)

    1995-11-09T23:59:59.000Z

    This paper shows that electrolytically generated crossed concentration gradients of viologen (2+) and viologen (1+) in films of its mixed valent molten salt on interdigitated array electrodes can be thermally and stably frozen in place in the interelectrode gaps. A study is presented of properties of the gradient-containing films, as compared to films that are non-mixed valent (V{sup 2+}) or that are mixed valent but lack concentration gradients. Comparisons of charge transport measurements show that the 2-5 {mu}m wide concentration gradients are persistent in the molten salt at lowered temperatures, where ionic motions are quenched relative to electron hopping as shown by differences in conductivity between mixed valent and non-mixed valent films as the temperature is lowered from +50 to -70{degree}C. Differences in the magnitude and shape of high-field current-voltage curves taken from mixed valent nongradient and V{sup 2+}/V{sup +} gradient-containing samples are interpreted with an electron-hopping model that includes a parameter for kinetic dispersity. Differences between the capacitance of the mixed valent and non-mixed valent phase of the viologen molten salt are consistent with the formation of an electronic space charge at the metal/redox conductor interface. 18 refs., 8 figs., 1 tab.

  7. Integrating 3D seismic curvature and curvature gradient attributes for fracture characterization: Methodologies and interpretational implications

    SciTech Connect (OSTI)

    Gao, Dengliang

    2013-03-01T23:59:59.000Z

    In 3D seismic interpretation, curvature is a popular attribute that depicts the geometry of seismic reflectors and has been widely used to detect faults in the subsurface; however, it provides only part of the solutions to subsurface structure analysis. This study extends the curvature algorithm to a new curvature gradient algorithm, and integrates both algorithms for fracture detection using a 3D seismic test data set over Teapot Dome (Wyoming). In fractured reservoirs at Teapot Dome known to be formed by tectonic folding and faulting, curvature helps define the crestal portion of the reservoirs that is associated with strong seismic amplitude and high oil productivity. In contrast, curvature gradient helps better define the regional northwest-trending and the cross-regional northeast-trending lineaments that are associated with weak seismic amplitude and low oil productivity. In concert with previous reports from image logs, cores, and outcrops, the current study based on an integrated seismic curvature and curvature gradient analysis suggests that curvature might help define areas of enhanced potential to form tensile fractures, whereas curvature gradient might help define zones of enhanced potential to develop shear fractures. In certain fractured reservoirs such as at Teapot Dome where faulting and fault-related folding contribute dominantly to the formation and evolution of fractures, curvature and curvature gradient attributes can be potentially applied to differentiate fracture mode, to predict fracture intensity and orientation, to detect fracture volume and connectivity, and to model fracture networks.

  8. Photon storage in Lambda-type optically dense atomic media. IV. Optimal control using gradient ascent

    E-Print Network [OSTI]

    Alexey V. Gorshkov; Tommaso Calarco; Mikhail D. Lukin; Anders S. Sorensen

    2008-04-07T23:59:59.000Z

    We use the numerical gradient ascent method from optimal control theory to extend efficient photon storage in Lambda-type media to previously inaccessible regimes and to provide simple intuitive explanations for our optimization techniques. In particular, by using gradient ascent to shape classical control pulses used to mediate photon storage, we open up the possibility of high efficiency photon storage in the non-adiabatic limit, in which analytical solutions to the equations of motion do not exist. This control shaping technique enables an order-of-magnitude increase in the bandwidth of the memory. We also demonstrate that the often discussed connection between time reversal and optimality in photon storage follows naturally from gradient ascent. Finally, we discuss the optimization of controlled reversible inhomogeneous broadening.

  9. Finite ballooning angle effects on ion temperature gradient driven mode in gyrokinetic flux tube simulations

    SciTech Connect (OSTI)

    Singh, Rameswar, E-mail: rameswar.singh@lpp.polytechnique.fr [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India) [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Laboratoire de Physique des Plasmas, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex (France); Brunner, S. [CRPP, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland)] [CRPP, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Ganesh, R. [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India)] [Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Jenko, F. [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)] [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

    2014-03-15T23:59:59.000Z

    This paper presents effects of finite ballooning angles on linear ion temperature gradient (ITG) driven mode and associated heat and momentum flux in Gyrokinetic flux tube simulation GENE. It is found that zero ballooning angle is not always the one at which the linear growth rate is maximum. The ITG mode acquires a short wavelength (SW) branch (k{sub ?}?{sub i}?>?1) when growth rates maximized over all ballooning angles are considered. However, the SW branch disappears on reducing temperature gradient showing characteristics of zero ballooning angle SWITG in case of extremely high temperature gradient. Associated heat flux is even with respect to ballooning angle and maximizes at nonzero ballooning angle while the parallel momentum flux is odd with respect to the ballooning angle.

  10. Millisecond ordering of block-copolymer films via photo-thermal gradients

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

    Majewski, Pawel W.; Yager, Kevin G.

    2015-04-28T23:59:59.000Z

    For the promise of self-assembly to be realized, processing techniques must be developed that simultaneously enable control of the nanoscale morphology, rapid assembly, and, ideally, the ability to pattern the nanostructure. Here, we demonstrate how photo-thermal gradients can be used to control the ordering of block-copolymer thin films. Highly localized laser heating leads to intense thermal gradients, which induce a thermophoretic force on morphological defects. This increases the ordering kinetics by at least 3 orders-of-magnitude, compared to conventional oven annealing. By simultaneously exploiting the thermal gradients to induce shear fields, we demonstrate uniaxial alignment of a block-copolymer film in lessmore »than a second. Finally, we provide examples of how control of the incident light-field can be used to generate prescribed configurations of block-copolymer nanoscale patterns.« less

  11. METALLICITY GRADIENTS IN THE MILKY WAY DISK AS OBSERVED BY THE SEGUE SURVEY

    SciTech Connect (OSTI)

    Cheng, Judy Y. [Department of Astronomy and Astrophysics, University of California Santa Cruz, Santa Cruz, CA 95064 (United States); Rockosi, Constance M. [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Morrison, Heather L. [Department of Astronomy, Case Western Reserve University, Cleveland, OH 44106 (United States); Schoenrich, Ralph A. [Max-Planck-Institute fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Lee, Young Sun; Beers, Timothy C. [Department of Physics and Astronomy and JINA (Joint Institute for Nuclear Astrophysics), Michigan State University, East Lansing, MI 48824 (United States); Bizyaev, Dmitry; Pan, Kaike [Apache Point Observatory, Sunspot, NM 88349 (United States); Schneider, Donald P., E-mail: jyc@ucolick.org [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2012-02-20T23:59:59.000Z

    The observed radial and vertical metallicity distribution of old stars in the Milky Way disk provides a powerful constraint on the chemical enrichment and dynamical history of the disk system. We present the radial metallicity gradient, {Delta}[Fe/H]/{Delta}R, as a function of height above the plane, |Z|, using 7010 main-sequence turnoff stars observed by the Sloan Extension for Galactic Understanding and Exploration survey. The sample consists of mostly old thin and thick disk stars, with a minimal contribution from the stellar halo, in the region 6 kpc < R < 16 kpc, 0.15 kpc < |Z| < 1.5 kpc. The data reveal that the radial metallicity gradient becomes flat at heights |Z| > 1 kpc. The median metallicity at large |Z| is consistent with the metallicities seen in outer disk open clusters, which exhibit a flat radial gradient at [Fe/H] {approx}-0.5. We note that the outer disk clusters are also located at large |Z|; because the flat gradient extends to small R for our sample, there is some ambiguity in whether the observed trends for clusters are due to a change in R or |Z|. We therefore stress the importance of considering both the radial and vertical directions when measuring spatial abundance trends in the disk. The flattening of the gradient at high |Z| also has implications on thick disk formation scenarios, which predict different metallicity patterns in the thick disk. A flat gradient, such as we observe, is predicted by a turbulent disk at high redshift, but may also be consistent with radial migration, as long as mixing is strong. We test our analysis methods using a mock catalog based on the model of Schoenrich and Binney, and we estimate our distance errors to be {approx}25%. We also show that we can properly correct for selection biases by assigning weights to our targets.

  12. Study of thermal-gradient-induced migration of brine inclusions in salt. Final report

    SciTech Connect (OSTI)

    Olander, D.R.

    1984-08-01T23:59:59.000Z

    Natural salt deposits, which are being considered for high-level waste disposal, contain a small volume fraction of water in the form of brine inclusions distributed throughout the salt. Radioactive decay heating of the nuclear wastes will impose a temperature gradient on the surrounding salt which mobilizes the brine inclusions. Inclusions filled completely with brine (the all-liquid inclusions) migrate up the temperature gradient and eventually accumulate brine near the buried waste forms. The brine may slowly corrode or degrade the waste forms, which is undesirable. Therefore it is important to consider the migration of brine inclusions in salt under imposed temperature gradients to properly evaluate the performance of a future salt repository for nuclear wastes. The migration velocities of the inclusions were found to be dependent on temperature, temperature gradient, and inclusion shape and size. The velocities were also dictated by the interfacial mass transfer resistance at brine/solid interface. This interfacial resistance depends on the dislocation density in the crystal, which in turn, depends on the axial compressive loading of the crystal. At low axial loads, the dependence between the velocity and temperature gradient is nonlinear. At high axial loads, the interfacial resistance is reduced and the migration velocity depends linearly on the temperature gradient. All-liquid inclusions filled with mixed brines were also studied. For gas-liquid inclusions, helium, air and argon were compared. Migration studies were also conducted on single crystallites of natural salt as well as in polycrystalline natural salt samples. The behavior of the inclusions at large-ange grain boundaries was observed.

  13. Caroline Twomey Lamb 2008 Collaborative Systems Thinking

    E-Print Network [OSTI]

    de Weck, Olivier L.

    , Systems Practice, Soft Systems Methodology: A 30-year retrospective. John Wiley and Sons, West Sussex© Caroline Twomey Lamb 2008 Collaborative Systems Thinking: Exploring systems thinking within teams 2008 Agenda · Motivation · Defining Systems Thinking ­ General Definitions ­ Engineering ­ Team

  14. Opportunistic, collaborative and synchronized, proximal device ecology

    E-Print Network [OSTI]

    Toledano, Eyal

    2013-01-01T23:59:59.000Z

    CoSync is an on-device software framework for coordinating proximal consumer electronic devices in order to create a synchronized, opportunistic and collaborative device ecology. The CoSync device ecology combines multiple ...

  15. Workflow Collaboration with Constraint Solving Capabilities 

    E-Print Network [OSTI]

    Chen-Burger, Y-H; Hui, K; Preece, A D; Gray, P.M.D; Tate, Austin

    , perform specialised tasks and achieve common goals. We give an account of our approach for the workflow assisted collaboration with a specialised knowledge agent. In this case, a system with constraint solving capabilities. We found that systems built...

  16. Webbed Footnotes : collaborative annotation on the Web

    E-Print Network [OSTI]

    Golder, Scott Andrew

    2005-01-01T23:59:59.000Z

    More and more, web users are moving from simply consuming content on the web to creating it as well, in the form of discussion boards, weblogs, wikis, and other collaborative and conversational media. Despite this, the web ...

  17. Progress Report for C-Mod Collaboration

    SciTech Connect (OSTI)

    Dr. Kenneth W. Gentle, Dr. William Rowan, Dr. Perry Phillips

    2008-09-30T23:59:59.000Z

    The aims of the collaboration have not changed. The report describes progress in the areas of FRCECE system, charge exchange recombination spectroscopy, Beam-Emission spectroscopy (BES), as well as other contributions. A significant number of resulting publications are listed.

  18. A component-based collaboration infrastructure 

    E-Print Network [OSTI]

    Yang, Yi

    2006-04-12T23:59:59.000Z

    Groupware applications allow geographically distributed users to collaborate on shared tasks. However, it is widely recognized that groupware applications are expensive to build due to coordination services and group ...

  19. Sources of stress gradients in electrodeposited Ni MEMS.

    SciTech Connect (OSTI)

    Hearne, Sean Joseph; Floro, Jerrold Anthony; Dyck, Christopher William

    2004-06-01T23:59:59.000Z

    The ability of future integrated metal-semiconductor micro-systems such as RF MEMS to perform highly complex functions will depend on developing freestanding metal structures that offer improved conductivity and reflectivity over polysilicon structures. For example, metal-based RF MEMS technology could replace the bulky RF system presently used in communications, navigation, and avionics systems. However, stress gradients that induce warpage of active components have prevented the implementation of this technology. Figure 1, is an interference micrograph image of a series of cantilever beams fabricated from electrodeposited Ni. The curvature in the beams was the result of stress gradients intrinsic to the electrodeposition process. To study the sources of the stress in electrodeposition of Ni we have incorporated a wafer curvature based stress sensor, the multibeam optical stress sensor, into an electrodeposition cell. We have determined that there are two regions of stress induced by electrodepositing Ni from a sulfamate-based bath (Fig 2). The stress evolution during the first region, 0-1000{angstrom}, was determined to be dependent only on the substrate material (Au vs. Cu), whereas the stress evolution during the second region, >1000{angstrom}, was highly dependent on the deposition conditions. In this region, the stress varied from +0.5 GPa to -0.5GPa, depending solely on the deposition rate. We examined four likely sources for the compressive intrinsic stress, i.e. reduction in tensile stress, and determined that only the adatom diffusion into grain boundaries model of Sheldon, et al. could account for the observed compressive stress. In the presentation, we shall discuss the compressive stress generation mechanisms considered and the ramifications of these results on fabrication of electrodeposited Ni for MEMS applications.

  20. Gearbox Reliability Collaborative (GRC) Description and Loading

    SciTech Connect (OSTI)

    Oyague, F.

    2011-11-01T23:59:59.000Z

    This document describes simulated turbine load cases in accordance to the IEC 61400-1 Ed.3 standard, which is representative of the typical wind turbine design process. The information presented herein is intended to provide a broad understanding of the gearbox reliability collaborative 750kW drivetrain and turbine configuration. In addition, fatigue and ultimate strength drivetrain loads resulting from simulations are presented. This information provides the bases for the analytical work of the gearbox reliability collaborative effort.

  1. Collaboration Results - Applying Technical Solutions To Environmental Remediation Problems

    SciTech Connect (OSTI)

    Boyd, G.; Fiore, J.; Walker, J.; DeRemer, C.; Wight, E.

    2002-02-26T23:59:59.000Z

    Within the Department of Energy's Office of Environmental Management (EM), the Office of Science and Technology (OST) identifies and develops innovative technologies that accelerate cleanup of high-priority environmental contamination problems and enable EM closure sites to meet closure schedules. OST manages an integrated research and development program that is essential to completing timely and cost-effective cleanup and stewardship of DOE sites. While innovative technologies can make significant contributions to the cleanup process, in some cases, EM has encountered unexpected barriers to their implementation. Technical obstacles are expected, but administrative challenges-such as regulatory, organizational, and stakeholder issues-must also be addressed. OST has found that collaborative needs identification and problem solving are essential components in overcoming these barriers. Collaboration helps EM meet its cleanup goals, close sites, and reduce the overall cost of cleanup at DOE sites nationwide. This paper presents examples of OST's collaboration efforts that expedite site closure and solve specific cleanup problems at EM sites.

  2. Constant field gradient planar coupled cavity structure

    DOE Patents [OSTI]

    Kang, Y.W.; Kustom, R.L.

    1999-07-27T23:59:59.000Z

    A cavity structure is disclosed having at least two opposing planar housing members spaced apart to accommodate the passage of a particle beam through the structure between the members. Each of the housing members have a plurality of serially aligned hollows defined therein, and also passages, formed in the members, which interconnect serially adjacent hollows to provide communication between the hollows. The opposing planar housing members are spaced and aligned such that the hollows in one member cooperate with corresponding hollows in the other member to form a plurality of resonant cavities aligned along the particle beam within the cavity structure. To facilitate the obtaining of a constant field gradient within the cavity structure, the passages are configured so as to be incrementally narrower in the direction of travel of the particle beam. In addition, the spacing distance between the opposing housing members is configured to be incrementally smaller in the direction of travel of the beam. 16 figs.

  3. Thermal Gradient Holes At Waunita Hot Springs Geothermal Area...

    Open Energy Info (EERE)

    Zacharakis, 1981) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Waunita Hot Springs Geothermal Area (Zacharakis,...

  4. Gradient methods for convex minimization: better rates under ...

    E-Print Network [OSTI]

    Hui Zhang

    2013-03-20T23:59:59.000Z

    Mar 20, 2013 ... Gradient methods for convex minimization: better rates under weaker conditions. Hui Zhang(hhuuii.zhang ***at*** gmail.com)

  5. Geology and Temperature Gradient Surveys Blue Mountain Geothermal...

    Open Energy Info (EERE)

    Gradient Surveys Blue Mountain Geothermal Discovery, Humboldt County, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Geology and...

  6. Thermal Gradient Holes At Blue Mountain Geothermal Area (Fairbank...

    Open Energy Info (EERE)

    search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Blue Mountain Geothermal Area (Fairbank & Ross, 1999) Exploration Activity Details Location...

  7. Thermal Gradient Holes At Blue Mountain Geothermal Area (Fairbank...

    Open Energy Info (EERE)

    Blue Mountain Geothermal Area (Fairbank & Niggemann, 2004) Exploration Activity Details Location Blue Mountain Geothermal Area Exploration Technique Thermal Gradient Holes Activity...

  8. Spatiotemporal Gradient Modeling with Applications Harrison S. Quick1

    E-Print Network [OSTI]

    Carlin, Bradley P.

    , and geospatial information storage, analysis, and distribution systems have led to a burgeoning of spatial 2.3 Gradient analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.5 Data analysis

  9. On the application of the spectral projected gradient method in ...

    E-Print Network [OSTI]

    2015-02-17T23:59:59.000Z

    On the application of the spectral projected gradient method in image segmentation. 7. (a) cameraman – 204 × 204. (b) carplate – 285 × 224. (c) granite – 225 × ...

  10. second-order convex splitting schemes for gradient flows with ...

    E-Print Network [OSTI]

    2011-11-08T23:59:59.000Z

    Abstract. We construct unconditionally stable, unconditionally uniquely solvable, and second-order accurate (in time) schemes for gradient flows with energy of ...

  11. Existence and uniqueness of global classical solutions of a gradient ...

    E-Print Network [OSTI]

    2015-01-22T23:59:59.000Z

    This gradient flow is generated by the Laudau-de Gennes energy functional that ... feature of this evolution problem is that it is generated by an energy functional ...

  12. Optimization Online - A three-term conjugate gradient method with ...

    E-Print Network [OSTI]

    Y Narushima

    2009-12-03T23:59:59.000Z

    Dec 3, 2009 ... A three-term conjugate gradient method with sufficient descent property for unconstrained optimization. Y Narushima(narusima ***at*** ...

  13. Optimization Online - Linearizing the Method of Conjugate Gradients

    E-Print Network [OSTI]

    Serge Gratton

    2012-09-09T23:59:59.000Z

    Sep 9, 2012 ... Abstract: The method of conjugate gradients (CG) is widely used for the iterative solution of large sparse systems of equations $Ax=b$, where ...

  14. A Perry Descent Conjugate Gradient Method with Restricted Spectrum

    E-Print Network [OSTI]

    Dongyi Liu

    2011-03-07T23:59:59.000Z

    Mar 7, 2011 ... Abstract: A new nonlinear conjugate gradient method, based on Perry's idea, is presented. And it is shown that its sufficient descent property is ...

  15. On the connection between the conjugate gradient method and ...

    E-Print Network [OSTI]

    Anders Forsgren

    2013-02-09T23:59:59.000Z

    Feb 9, 2013 ... Abstract: It is well known that the conjugate gradient method and a quasi-Newton method, using any well-defined update matrix from the ...

  16. A Nonmonotone Approach without Differentiability Test for Gradient ...

    E-Print Network [OSTI]

    Elias S. Helou

    2015-03-18T23:59:59.000Z

    Mar 18, 2015 ... A Nonmonotone Approach without Differentiability Test for Gradient Sampling Methods. Elias S. Helou(elias ***at*** icmc.usp.br) Sandra A.

  17. Concentration Gradient and Information Energy for Decentralized UAV Control1

    E-Print Network [OSTI]

    Mohseni, Kamran

    spills, industrial release accidents, or chemical/biological/nuclear terrorist attacks. DependingConcentration Gradient and Information Energy for Decentralized UAV Control1 William J. Pisano2

  18. Thermal Gradient Holes At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    Geothermal Area (Farrar, Et Al., 2003) Exploration Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1998 -...

  19. alpine elevation gradient: Topics by E-print Network

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

    Niche expansion leads to small-scale adaptive divergence along an elevation gradient in a medium of the Environment, University of California, Los Angeles, CA 90095, USA Niche...

  20. An accelerated proximal gradient algorithm for nuclear norm ...

    E-Print Network [OSTI]

    Kim-Chuan Toh

    2009-03-27T23:59:59.000Z

    Mar 27, 2009 ... An accelerated proximal gradient algorithm for nuclear norm regularized least squares problems. Kim-Chuan Toh (mattohkc ***at*** nus.edu.sg)

  1. Thermal Gradient Holes At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1991 - 1991 Usefulness not useful DOE-funding Unknown...

  2. Thermal Gradient Holes At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    Activity Details Location Long Valley Caldera Geothermal Area Exploration Technique Thermal Gradient Holes Activity Date 1978 - 1985 Usefulness useful DOE-funding Unknown...

  3. Thermal Gradient Holes At North Brawley Geothermal Area (Edmunds...

    Open Energy Info (EERE)

    of the North Brawley, Heber, East Mesa, and Salton Sea Geothermal Areas. Notes Well logs, thermal gradient data, and magnetic data were correlated to form a better geologic...

  4. Thermal Gradient Holes At Lightning Dock Geothermal Area (Cunniff...

    Open Energy Info (EERE)

    Thermal Gradient Holes At Lightning Dock Geothermal Area (Cunniff & Bowers, 2005) Exploration Activity Details Location Lightning Dock Geothermal Area Exploration Technique Thermal...

  5. Thermal Gradient Holes At North Brawley Geothermal Area (Matlick...

    Open Energy Info (EERE)

    Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At North Brawley Geothermal Area (Matlick & Jayne, 2008) Exploration...

  6. Search for VHE emission from GRB with P. M. Saz Parkinson for the Milagro Collaboration1

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Search for VHE emission from GRB with Milagro P. M. Saz Parkinson for the Milagro Collaboration1 is uniquely capable of searching for very high-energy emission from gamma-ray bursts (GRB) during the prompt emission phase because of its wide field of view and high duty cycle, monitoring the northern sky almost

  7. Thermal Gradient Holes At Spencer Hot Springs Area (Shevenell...

    Open Energy Info (EERE)

    Activity Date Usefulness useful DOE-funding Unknown Notes Collaboration with the gold mining industry has brought two new geothermal discoveries to the attention of the geothermal...

  8. National Wind Distance Learning Collaborative

    SciTech Connect (OSTI)

    Dr. James B. Beddow

    2013-03-29T23:59:59.000Z

    Executive Summary The energy development assumptions identified in the Department of Energy's position paper, 20% Wind Energy by 2030, projected an exploding demand for wind energy-related workforce development. These primary assumptions drove a secondary set of assumptions that early stage wind industry workforce development and training paradigms would need to undergo significant change if the workforce needs were to be met. The current training practice and culture within the wind industry is driven by a relatively small number of experts with deep field experience and knowledge. The current training methodology is dominated by face-to-face, classroom based, instructor present training. Given these assumptions and learning paradigms, the purpose of the National Wind Distance Learning Collaborative was to determine the feasibility of developing online learning strategies and products focused on training wind technicians. The initial project scope centered on (1) identifying resources that would be needed for development of subject matter and course design/delivery strategies for industry-based (non-academic) training, and (2) development of an appropriate Learning Management System (LMS). As the project unfolded, the initial scope was expanded to include development of learning products and the addition of an academic-based training partner. The core partners included two training entities, industry-based Airstreams Renewables and academic-based Lake Area Technical Institute. A third partner, Vision Video Interactive, Inc. provided technology-based learning platforms (hardware and software). The revised scope yielded an expanded set of results beyond the initial expectation. Eight learning modules were developed for the industry-based Electrical Safety course. These modules were subsequently redesigned and repurposed for test application in an academic setting. Software and hardware developments during the project's timeframe enabled redesign providing for student access through the use of tablet devices such as iPads. Early prototype Learning Management Systems (LMS) featuring more student-centric access and interfaces with emerging social media were developed and utilized during the testing applications. The project also produced soft results involving cross learning between and among the partners regarding subject matter expertise, online learning pedagogy, and eLearning technology-based platforms. The partners believe that the most significant, overarching accomplishment of the project was the development and implementation of goals, activities, and outcomes that significantly exceeded those proposed in the initial grant application submitted in 2009. Key specific accomplishments include: (1) development of a set of 8 online learning modules addressing electrical safety as it relates to the work of wind technicians; (3) development of a flexible, open-ended Learning Management System (LMS): (3) creation of a robust body of learning (knowledge, experience, skills, and relationships). Project leaders have concluded that there is substantial resource equity that could be leverage and recommend that it be carried forward to pursue a Next Stage Opportunity relating to development of an online core curriculum for institute and community college energy workforce development programs.

  9. SampleRank: Training Factor Graphs with Atomic Gradients

    E-Print Network [OSTI]

    McCallum, Andrew

    a user-provided loss function to distribute stochastic gradients across an MCMC chain. As a result, parameter updates can be computed between arbitrary MCMC states. Sam- pleRank is not only faster than CD- expensive gradients between the ground-truth and samples along an MCMC chain yielding a stochastic

  10. The Simplex Gradient and Noisy Optimization Problems \\Lambda

    E-Print Network [OSTI]

    The Simplex Gradient and Noisy Optimization Problems \\Lambda D. M. Bortz C. T. Kelley North the simplex gradient from [14], the first order estimates it satisfies, and its application to the Nelder/or exploit parallelism. The algorithms we discuss in this paper all examine a simplex of points in R N

  11. Dynamics of the Dorsal morphogen gradient Jitendra S. Kanodiaa

    E-Print Network [OSTI]

    Shvartsman, Stanislav "Stas"

    Dynamics of the Dorsal morphogen gradient Jitendra S. Kanodiaa , Richa Rikhyb , Yoosik Kima Road, Princeton, NJ 08544; bCell Biology and Metabolism Branch, NIH, Building 32, 18 Library Drive localization gradient of Dorsal (Dl), a protein related to the mammalian NF- B transcription factors. Current

  12. Enhancing Optical Gradient Forces with Metamaterials Vincent Ginis,1

    E-Print Network [OSTI]

    Enhancing Optical Gradient Forces with Metamaterials Vincent Ginis,1 Philippe Tassin,2,* Costas M demonstrate how the optical gradient force between two waveguides can be enhanced using transformation optics perceived by light, resulting in a more than tenfold enhancement of the optical force. This process

  13. Combining Conjugate Direction Methods with Stochastic Approximation of Gradients

    E-Print Network [OSTI]

    Schraudolph, Nicol N.

    Combining Conjugate Direction Methods with Stochastic Approximation of Gradients #3; Nicol N-8092 Zurich, Switzerland http://www.icos.ethz.ch/ Abstract The method of conjugate directions provides from conjugate gra- dient in the stochastic (online) setting, us- ing fast Hessian-gradient products

  14. Combining Conjugate Direction Methods with Stochastic Approximation of Gradients

    E-Print Network [OSTI]

    Schraudolph, Nicol N.

    Combining Conjugate Direction Methods with Stochastic Approximation of Gradients Nicol N-8092 Z¨urich, Switzerland http://www.icos.ethz.ch/ Abstract The method of conjugate directions provides conjugate gra- dient in the stochastic (online) setting, us- ing fast Hessian-gradient products to set up

  15. Generalized Hooke's law for isotropic second gradient materials

    E-Print Network [OSTI]

    F. dell'Isola; G. Sciarra; S. Vidoli

    2010-08-17T23:59:59.000Z

    In the spirit of Germain the most general objective stored elastic energy for a second gradient material is deduced using a literature result of Fortun\\'e & Vall\\'ee. Linear isotropic constitutive relations for stress and hyperstress in terms of strain and strain-gradient are then obtained proving that these materials are characterized by seven elastic moduli and generalizing previous studies by Toupin, Mindlin and Sokolowski. Using a suitable decomposition of the strain-gradient, it is found a necessary and sufficient condition, to be verified by the elastic moduli, assuring positive definiteness of the stored elastic energy. The problem of warping in linear torsion of a prismatic second gradient cylinder is formulated, thus obtaining a possible measurement procedure for one of the second gradient elastic moduli.

  16. Collaborator Checklist | Linac Coherent Light Source

    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 Office511041clothAdvanced Materials Advanced. C o w l i tCollaboration March 16, 2010 DuringCollaborator

  17. A complete implementation of the conjugate gradient algorithm on a reconfigurable supercomputer

    SciTech Connect (OSTI)

    Dubois, David H [Los Alamos National Laboratory; Dubois, Andrew J [Los Alamos National Laboratory; Connor, Carolyn M [Los Alamos National Laboratory; Boorman, Thomas M [Los Alamos National Laboratory; Poole, Stephen W [ORNL

    2008-01-01T23:59:59.000Z

    The conjugate gradient is a prominent iterative method for solving systems of sparse linear equations. Large-scale scientific applications often utilize a conjugate gradient solver at their computational core. In this paper we present a field programmable gate array (FPGA) based implementation of a double precision, non-preconditioned, conjugate gradient solver for fmite-element or finite-difference methods. OUf work utilizes the SRC Computers, Inc. MAPStation hardware platform along with the 'Carte' software programming environment to ease the programming workload when working with the hybrid (CPUIFPGA) environment. The implementation is designed to handle large sparse matrices of up to order N x N where N <= 116,394, with up to 7 non-zero, 64-bit elements per sparse row. This implementation utilizes an optimized sparse matrix-vector multiply operation which is critical for obtaining high performance. Direct parallel implementations of loop unrolling and loop fusion are utilized to extract performance from the various vector/matrix operations. Rather than utilize the FPGA devices as function off-load accelerators, our implementation uses the FPGAs to implement the core conjugate gradient algorithm. Measured run-time performance data is presented comparing the FPGA implementation to a software-only version showing that the FPGA can outperform processors running up to 30x the clock rate. In conclusion we take a look at the new SRC-7 system and estimate the performance of this algorithm on that architecture.

  18. Polyelectrolyte Materials for High Temperature Fuel Cells

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

    High 3M (3M) Temperature Fuel Cells John B. Kerr Lawrence Berkeley National Laboratory (LBNL) Collaborators: Los Alamos National Laboratory (LANL). February 13, 2007 This...

  19. Natural Conjugate Gradient on Complex Flag Manifolds for Complex Independent Subspace

    E-Print Network [OSTI]

    Plumbley, Mark

    conjugate gradient method yields better convergence compared to the natural gradient geodesic search method is the natural gradient geodesic search method (NGS), and the other is the natural conjugate gradient method (NCG the natural gradient or the Newton's method on complex manifolds, however, the behavior of the conjugate

  20. A conjugate Rosen's gradient projection method with global line search for piecewise linear optimization

    E-Print Network [OSTI]

    Beltran-Royo, Cesar

    A conjugate Rosen's gradient projection method with global line search for piecewise linear cutting plane method, simplex method, Rosen's gradient projection, conjugate gradient. 1 Introduction the zig-zagging of the gradient projection, we propose a conjugate gradient version of the face simplex

  1. An approach to control collaborative processes in PLM systems

    E-Print Network [OSTI]

    Kadiri, Soumaya El; Delattre, Miguel; Bouras, Abdelaziz

    2008-01-01T23:59:59.000Z

    Companies that collaborate within the product development processes need to implement an effective management of their collaborative activities. Despite the implementation of a PLM system, the collaborative activities are not efficient as it might be expected. This paper presents an analysis of the problems related to the collaborative work using a PLM system. From this analysis, we propose an approach for improving collaborative processes within a PLM system, based on monitoring indicators. This approach leads to identify and therefore to mitigate the brakes of the collaborative work.

  2. Strict convexity of the free energy for non-convex gradient models at moderate $?$

    E-Print Network [OSTI]

    Codina Cotar; Jean-Dominique Deuschel; Stefan Müller

    2008-01-08T23:59:59.000Z

    We consider a gradient interface model on the lattice with interaction potential which is a non-convex perturbation of a convex potential. We show using a one-step multiple scale analysis the strict convexity of the surface tension at high temperature. This is an extension of Funaki and Spohn's result, where the strict convexity of potential was crucial in their proof that for every tilt there is a unique, shift invariant, ergodic Gibbs measure for the $\

  3. AFS and the Web: Competitors or Collaborators?

    E-Print Network [OSTI]

    Newhall, Tia

    AFS and the Web: Competitors or Collaborators? M. Satyanarayanan Mirjana Spasojevic Carnegie Mellon­Wide Web and AFS represent two different approaches to the problem of large­scale information sharing and weaknesses. Our comparison shows that the Web and AFS are not really competing technologies. Rather

  4. Power and Energy Engineering Workforce Collaborative

    E-Print Network [OSTI]

    needs and global concerns * Source: US Department of Energy, Annual Energy Outlook 2007 Early Release1 Power and Energy Engineering Workforce Collaborative NERC Webinar July 8, 2008 #12;22 Overview and Concerns · NSF Workforce Workshop and Recommendations · Shifting the Education Paradigm · Power and Energy

  5. Collaborative Virtual Environment Standards: A Performance Evaluation

    E-Print Network [OSTI]

    Ottawa, University of

    for each standard varies from graphics and rendering to simulation and network communication. Standards categories: Rendering and Graphics and Communications Middleware. 2.1 Rendering and Graphics These standards1 Collaborative Virtual Environment Standards: A Performance Evaluation Jauvane C. de Oliveira

  6. SUPPORTING COLLABORATIVE WRITING OF XML DOCUMENTS

    E-Print Network [OSTI]

    Boyer, Edmond

    SUPPORTING COLLABORATIVE WRITING OF XML DOCUMENTS G´erald Oster, Hala Skaf-Molli, Pascal Molli: Data management is a key issue in cooperative systems. Anyone who uses more than one computer or collab- orates with other people is aware of the problems posed by having multiple copies of shared documents

  7. 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

  8. Indiana University Collaborative Research Grants 2012 2013

    E-Print Network [OSTI]

    Menczer, Filippo

    to faculty on all Indiana University campuses. Funding decisions will result from a competitive peer review University's New Frontiers seed funding program. Eligibility: All faculty and staff whose appointments allowIndiana University Collaborative Research Grants 2012 ­ 2013 Indiana University is pleased

  9. Collaborative Approach World-Class Facilities

    E-Print Network [OSTI]

    Chen, Tsuhan

    .5 million from the Department of Energy, along with additional funds from New York State, for an EnergyWCMC Collaborative Approach World-Class Facilities Research at Cornell /A Statistical Excerpt York 08 Funding Cornell's Research 09 Expending Research Dollars 10 Funding Graduate Education 12

  10. Collaborative Partnerships in Health, Medicine & Social Care

    E-Print Network [OSTI]

    Meju, Max

    Collaborative Partnerships in Health, Medicine & Social Care Launch Conference Lancaster University and globally in Health, Medicine and Social Care. Guest Speakers will include: Dr Louise Wood (Head sector in research, knowledge exchange and professional development across all fields of Health, Medicine

  11. Canada's National Forest Inventory An Interagency Collaboration

    E-Print Network [OSTI]

    Canada's National Forest Inventory An Interagency Collaboration Mark Gillis and Michael Brady: · Timber supply analysis · Management unit planning Management Inventory #12;· Canada's NFI-2001 ­ NFI 2006... National Inventory #12;Canada's National Forest Inventory (1976-2001) ­ compilation

  12. Measurement of Magnetic Field Using Collaborative AUVs

    E-Print Network [OSTI]

    Idaho, University of

    Measurement of Magnetic Field Using Collaborative AUVs Jesse Pentzer, Brendan Crosbie, Thomas Bean, tests using multiple types of AUVs to individually sample bathymetric data and water mass properties, salinity, and temperature data was reported [2]. In 2007, an AUV was equipped to measure water properties

  13. Gearbox Reliability Collaborative: Gearbox Inspection Metadata

    SciTech Connect (OSTI)

    Munch, K.; McDade, M.

    2010-09-01T23:59:59.000Z

    NREL has developed a software application called GearFacts that will be distributed to Database Collaborative participants to capture failure information when gearboxes are rebuilt. This publication names and describes each field used in GearFacts and can be used as a reference to the software's design.

  14. 1 HERMES collaboration. A. Airapetian (Giessen U. &

    E-Print Network [OSTI]

    Titov, Anatoly

    1 HERMES collaboration. A. Airapetian (Giessen U. & Michigan U.), N. Akopov (Yerevan Phys. Inst.), Z. Akopov (DESY), E.C. Aschenauer (DESY, Zeuthen), W. Augustyniak (Warsaw, Inst. Nucl. Studies), R (Giessen U. & Michigan U.), N. Akopov (Yerevan Phys. Inst.), Z. Akopov (DESY), E.C. Aschenauer (DESY

  15. JET Forward Programme & Opportunities for Collaboration

    E-Print Network [OSTI]

    JET Forward Programme & Opportunities for Collaboration Lorne Horton JET Exploitation Manager Contract for the Opera.on of the JET Facili.es Co-Funded by Euratom #12;L.D. Horton 2 FESAC Strategic Planning Panel 8 July 2014 - What makes JET unique! - Plans for JET exploitation

  16. COLLABORATIVE AND SOCIAL Faculty: Mark Ackerman

    E-Print Network [OSTI]

    Eustice, Ryan

    Research The Interactive Systems group investigates Human- Computer Interaction (HCI), Educational Technology, Multimedia to find people; new collaborative interfaces for reusing informal information; user control in pervasive activity, and learning. The applications cover a wide span: user interface design methods, computa- tional

  17. INTERNATIONAL COLLABORATION ON CO2 SEQUESTRATION

    SciTech Connect (OSTI)

    Howard J. Herzog; E. Eric Adams

    2005-04-01T23:59:59.000Z

    On December 4, 1997, the US Department of Energy (DOE), the New Energy and Industrial Technology Development Organization of Japan (NEDO), and the Norwegian Research Council (NRC) entered into a ''Project Agreement for International Collaboration on CO{sub 2} Ocean Sequestration''. Government organizations from Japan, Canada, and Australia, and a Swiss/Swedish engineering firm later joined the agreement, which outlined a research strategy for ocean carbon sequestration via direct injection. The members agreed to an initial field experiment, with the hope that if the initial experiment was successful, there would be subsequent field evaluations of increasingly larger scale to evaluate environmental impacts of sequestration and the potential for commercialization. This report is a summary of the evolution of the collaborative effort, the supporting research, and results for the International Collaboration on CO{sub 2} Ocean Sequestration. Almost 100 papers and reports resulted from this collaboration, including 18 peer reviewed journal articles, 46 papers, 28 reports, and 4 graduate theses. A full listing of these publications is in the reference section.

  18. Collaboration Suite Advanced Web Client User Guide

    E-Print Network [OSTI]

    Shepp, Larry

    ZimbraTM Collaboration Suite Advanced Web Client User Guide Version 5.0 #12;Zimbra Web Client User Guide Copyright Notice Copyright © 2008 Zimbra, Inc. All rights reserved materials, onscreen publication, or Web documentation--is expressly forbidden. Zimbra and the Zimbra logo

  19. Granular Context in Collaborative Mobile Environments

    E-Print Network [OSTI]

    Dustdar, Schahram

    facets of collaboration cover the whole life cycle of con- text information: sensing, aggregating teams. We present a methodology for context modeling and employ a framework that reduces costs/wireless setting, but also computing power needed to process information, and thus battery consumption R. Meersman

  20. Efficient and robust gradient enhanced Kriging emulators.

    SciTech Connect (OSTI)

    Dalbey, Keith R.

    2013-08-01T23:59:59.000Z

    %E2%80%9CNaive%E2%80%9D or straight-forward Kriging implementations can often perform poorly in practice. The relevant features of the robustly accurate and efficient Kriging and Gradient Enhanced Kriging (GEK) implementations in the DAKOTA software package are detailed herein. The principal contribution is a novel, effective, and efficient approach to handle ill-conditioning of GEK's %E2%80%9Ccorrelation%E2%80%9D matrix, RN%CC%83, based on a pivoted Cholesky factorization of Kriging's (not GEK's) correlation matrix, R, which is a small sub-matrix within GEK's RN%CC%83 matrix. The approach discards sample points/equations that contribute the least %E2%80%9Cnew%E2%80%9D information to RN%CC%83. Since these points contain the least new information, they are the ones which when discarded are both the easiest to predict and provide maximum improvement of RN%CC%83's conditioning. Prior to this work, handling ill-conditioned correlation matrices was a major, perhaps the principal, unsolved challenge necessary for robust and efficient GEK emulators. Numerical results demonstrate that GEK predictions can be significantly more accurate when GEK is allowed to discard points by the presented method. Numerical results also indicate that GEK can be used to break the curse of dimensionality by exploiting inexpensive derivatives (such as those provided by automatic differentiation or adjoint techniques), smoothness in the response being modeled, and adaptive sampling. Development of a suitable adaptive sampling algorithm was beyond the scope of this work; instead adaptive sampling was approximated by omitting the cost of samples discarded by the presented pivoted Cholesky approach.

  1. LAGOVirtual: A Collaborative Environment for the Large Aperture GRB Observatory

    E-Print Network [OSTI]

    R. Camacho; R. Chacon; G. Diaz; C. Guada; V. Hamar; H. Hoeger; A. Melfo; L. A. Nunez; Y. Perez; C. Quintero; M. Rosales; R. Torrens; the LAGO Collaboration

    2009-12-12T23:59:59.000Z

    We present the LAGOVirtual Project: an ongoing project to develop platform to collaborate in the Large Aperture GRB Observatory (LAGO). This continental-wide observatory is devised to detect high energy (around 100 GeV) component of Gamma Ray Bursts, by using the single particle technique in arrays of Water Cherenkov Detectors (WCD) at high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). This platform will allow LAGO collaboration to share data, and computer resources through its different sites. This environment has the possibility to generate synthetic data by simulating the showers through AIRES application and to store/preserve distributed data files collected by the WCD at the LAGO sites. The present article concerns the implementation of a prototype of LAGO-DR adapting DSpace, with a hierarchical structure (i.e. country, institution, followed by collections that contain the metadata and data files), for the captured/simulated data. This structure was generated by using the community, sub-community, collection, item model; available at the DSpace software. Each member institution-country of the project has the appropriate permissions on the system to publish information (descriptive metadata and associated data files). The platform can also associate multiple files to each item of data (data from the instruments, graphics, postprocessed-data, etc.).

  2. LAGOVirtual: A Collaborative Environment for the Large Aperture GRB Observatory

    E-Print Network [OSTI]

    Camacho, R; Diaz, G; Guada, C; Hamar, V; Hoeger, H; Melfo, A; Nunez, L A; Perez, Y; Quintero, C; Rosales, M; Torrens, R

    2009-01-01T23:59:59.000Z

    We present the LAGOVirtual Project: an ongoing project to develop platform to collaborate in the Large Aperture GRB Observatory (LAGO). This continental-wide observatory is devised to detect high energy (around 100 GeV) component of Gamma Ray Bursts, by using the single particle technique in arrays of Water Cherenkov Detectors (WCD) at high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). This platform will allow LAGO collaboration to share data, and computer resources through its different sites. This environment has the possibility to generate synthetic data by simulating the showers through AIRES application and to store/preserve distributed data files collected by the WCD at the LAGO sites. The present article concerns the implementation of a prototype of LAGO-DR adapting DSpace, with a hierarchical structure (i.e. country, institution, followed by collections that contain the metadata and data files), for the captured/simulate...

  3. Subwavelength silicon through-hole arrays as an all-dielectric broadband terahertz gradient index metamaterial

    SciTech Connect (OSTI)

    Park, Sang-Gil; Jeong, Ki-Hun, E-mail: kjeong@kaist.ac.kr [Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); KAIST Institute for Optical Science and Technology, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Kanghee; Han, Daehoon; Ahn, Jaewook [KAIST Institute for Optical Science and Technology, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2014-09-01T23:59:59.000Z

    Structuring at subwavelength scales brings out artificial media with anomalous optical features called metamaterials. All-dielectric metamaterials have high potential for practical applications over the whole electromagnetic spectrum owing to low loss and optical isotropy. Here, we report subwavelength silicon through-hole arrays as an all-dielectric gradient index metamaterial with broadband THz operation. The unit cell consists of a single subwavelength through-hole on highly resistive monocrystalline silicon. Depending on the fill-factor and period, the effective index was linearly modulated at 0.3–1.6 THz. The experimental results also demonstrate silicon gradient refractive index (Si-GRIN) lenses with parabolic index profiles through the spatial modification of a single unit cell along the radial direction. Si-GRIN lenses either focus 0.4–1.6 THz beam to the diffraction-limit or serve as a flat and thin solid immersion lens on the backside of THz photoconductive antenna for highly efficient pulse extraction. This all-dielectric gradient index metamaterial opens up opportunities for integrated THz GRIN optics.

  4. Investigation of Turbulent transition in plane Couette flows Using Energy Gradient Method

    E-Print Network [OSTI]

    Hua-Shu Dou; Boo Cheong Khoo

    2010-06-07T23:59:59.000Z

    The energy gradient method has been proposed with the aim of better understanding the mechanism of flow transition from laminar flow to turbulent flow. In this method, it is demonstrated that the transition to turbulence depends on the relative magnitudes of the transverse gradient of the total mechanical energy which amplifies the disturbance and the energy loss from viscous friction which damps the disturbance, for given imposed disturbance. For a given flow geometry and fluid properties, when the maximum of the function K (a function standing for the ratio of the gradient of total mechanical energy in the transverse direction to the rate of energy loss due to viscous friction in the streamwise direction) in the flow field is larger than a certain critical value, it is expected that instability would occur for some initial disturbances. In this paper, using the energy gradient analysis, the equation for calculating the energy gradient function K for plane Couette flow is derived. The result indicates that K reaches the maximum at the moving walls. Thus, the fluid layer near the moving wall is the most dangerous position to generate initial oscillation at sufficient high Re for given same level of normalized perturbation in the domain. The critical value of K at turbulent transition, which is observed from experiments, is about 370 for plane Couette flow when two walls move in opposite directions (anti-symmetry). This value is about the same as that for plane Poiseuille flow and pipe Poiseuille flow (385-389). Therefore, it is concluded that the critical value of K at turbulent transition is about 370-389 for wall-bounded parallel shear flows which include both pressure (symmetrical case) and shear driven flows (anti-symmetrical case).

  5. collaboration (Fig. 1). For all their promise, the LCLS and XFEL are large and expensive; the

    E-Print Network [OSTI]

    Cai, Long

    an existing particle accelera- tor, is about 300 million ($450 million), and XFEL will cost about 1 billion by combining the technology of lasers and electron accelerators (Fig. 2). A particle accelerator produces X-FEL. An even more advanced instrument under consideration6,7 is a high-gradient accel- erator

  6. Collaborative Governance: Emerging Practices and the Incomplete Legal Framework for Citizen Stakeholder Voice

    E-Print Network [OSTI]

    Bingham, Lisa Blomgren

    2008-01-01T23:59:59.000Z

    new governance examples from collaborative public management,New Legal Infrastructure for Encouraging Collaborative Public Managementnew governance is here to stay. Collaborative public management

  7. Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method

    E-Print Network [OSTI]

    Nocedal, Jorge

    Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method Jos subroutines for automatically generating pre­ conditioners for the conjugate gradient method. It is designed. Additional Key Words and Phrases: Preconditioning, conjugate gradient method, quasi­ Newton method, Hessian

  8. COMPARISON OF THE DEFLATED PRECONDITIONED CONJUGATE GRADIENT METHOD AND ALGEBRAIC MULTIGRID FOR COMPOSITE

    E-Print Network [OSTI]

    MacLachlan, Scott

    COMPARISON OF THE DEFLATED PRECONDITIONED CONJUGATE GRADIENT METHOD AND ALGEBRAIC MULTIGRID algorithms such as the Preconditioned Conjugate Gradient (PCG) method. This paper considers the Deflated Preconditioned Conjugate Gradient (DPCG) method in which the rigid body modes of sets of elements

  9. CUNY EXPORT CONTROL PROCEDURES 14. International Collaboration Agreements

    E-Print Network [OSTI]

    Rosen, Jay

    CUNY EXPORT CONTROL PROCEDURES 14. International Collaboration Agreements This section addresses the process for managing export control requirements associated with international collaborations with potential international research partners. Several export control requirements are applicable. When drafting

  10. sp[A.C.E.]: Student's Personal Academic Collaboration Environments

    E-Print Network [OSTI]

    Kosary, Cozette Jordan

    2012-05-31T23:59:59.000Z

    This project seeks to discover where students living in the dorms currently perform academic collaboration. Academic collaboration is the methods students use to study and get the most out of their academic career. The ...

  11. Hierarchical multi-touch selection techniques for collaborative geospatial analysis

    E-Print Network [OSTI]

    Wartell, Zachary

    Hierarchical multi-touch selection techniques for collaborative geospatial analysis Thomas and military use. Keywords: Multi-touch, hierarchical selection, geospatial analysis, GIS, collaborative selection of complex regions-of-interest within a hierarchical geospatial environment, as well as methods

  12. PROCEEDINGS Open Access Recent advances in standards for collaborative

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    PROCEEDINGS Open Access Recent advances in standards for collaborative Digital Anatomic Pathology. Collaborative Digital Anatomic Pathology can only be fully achieved using medical informatics standards specifying how medical informatics standards should be implemented to meet specific health care needs

  13. DOE to Launch Collaborative Effort with Industry to Improve Natural...

    Energy Savers [EERE]

    29, 2014 - 2:54pm Addthis DOE to Launch Collaborative Effort with Industry to Improve Natural Gas Systems DOE will launch a collaborative effort with industry to evaluate and scope...

  14. Integrated Scenario-based Design Methodology for Collaborative Technology Innovation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Integrated Scenario-based Design Methodology for Collaborative Technology Innovation Fabrice Forest information technology innovation with an end-to-end Human and Social Sciences assistance. This methodology Technological innovation often requires large scale collaborative partnership between many heterogeneous

  15. Fusion Tables : new ways to collaborate on structured data

    E-Print Network [OSTI]

    Kidon, Jonathan Goldberg

    2010-01-01T23:59:59.000Z

    Fusion Tables allows data collaborators to create, merge, navigate and set access control permissions on structured data. This thesis focuses on the collaboration tools that were added to Googles Fusion Tables. The ...

  16. Evaluation of Profile Injection Attacks In Collaborative Recommender Systems

    E-Print Network [OSTI]

    Schaefer, Marcus

    Evaluation of Profile Injection Attacks In Collaborative Recommender Systems Chad Williams, Runa recommender systems. The open nature of collaborative filtering allows attackers to inject biased profile data identified attack profiles. Second, we analyze the effectiveness of a supervised classification approach

  17. COLLABORATIVE INVESTIGATIONS OF WATER QUALITY POLLUTION PATTERNS: WORKING WITH

    E-Print Network [OSTI]

    COLLABORATIVE INVESTIGATIONS OF WATER QUALITY POLLUTION PATTERNS: WORKING WITH THE KYUQUOT and Environmental Management Title of Research Project: Collaborative Investigations of Water Quality Pollution 15, 2006 #12;iii ABSTRACT In 2004, large-scale closures to shellfish harvesting were issued

  18. COLLABORATIVE DESIGN PEDAGOGY: A NATURALISTIC INQUIRY OF ARCHITECTURAL EDUCATION

    E-Print Network [OSTI]

    McPeek, Keith T.

    2010-07-14T23:59:59.000Z

    of collaborative methods in the context of situated learning. This research explores the notion that the design and implementation of even the simplest architectural projects are almost exclusively collaborative endeavors requiring the expertise of a spectrum...

  19. Collaborative Systems Thinking Research: Exploring systems thinking within teams

    E-Print Network [OSTI]

    de Weck, Olivier L.

    Collaborative Systems Thinking Research: Exploring systems thinking within teams Caroline T. Lamb research that seeks to develop an empirical basis for collaborative systems thinking, defined as "an of thinking styles, design processes, tools, and communication media to consider system attributes

  20. An Architecture for Collaboratively Assembled Moderated Information Bearing Web Sites

    E-Print Network [OSTI]

    Cooper, R.L.

    Cooper,R.L. Proceedings of Web Based Collaboration, DEXA, 2002 pp 293-297 IEEE Computer Society Press

  1. Collaborative 3D Visualization on Large Screen Displays

    E-Print Network [OSTI]

    Barbosa, Alberto

    reality (VR) system designed to support collaborative visualization of 3D environments, applied in collaborative work. This paper presents a system that uses remotely located wall sized displays, to offer immersive, interactive collaborative visualization and review of 3D CAD models for engineering applications

  2. KIPAC, Dec. 17, 2009 Jodi Cooley, SMU, CDMS Collaboration

    E-Print Network [OSTI]

    California at Berkeley, University of

    KIPAC, Dec. 17, 2009 Jodi Cooley, SMU, CDMS Collaboration New Results from the Final Runs Collaboration 1 #12;SLAC, Dec. 17, 2009 Jodi Cooley, SMU, CDMS Collaboration Overview · What we know and what we CDMS II data runs · The future · SuperCDMS 2 #12;SLAC, Dec. 17, 2009 Jodi Cooley, SMU, CDMS

  3. A COLLABORATIVE ENVIRONMENT FOR ACTORS FOR SUSTAINABLE DEVELOPMENT

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 A COLLABORATIVE ENVIRONMENT FOR ACTORS FOR SUSTAINABLE DEVELOPMENT �ve ROSS Maître de conférences facilitating a collaborative environment in the field of architecture and urban design. Desk research by way in an international effort. Keywords: Territorial intelligence, 3D virtual collaborative environment, sustainable

  4. Informedness in Collaborative Networks Through Active Information Provisioning

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Database Systems 1 Introduction Companies seek to improve their competitive position by collaborating collaborate in different areas such as knowledge sharing and joint product development [1]. It also can with other companies in collaborative networks [2] that are expected to provide many potential benefits

  5. Distributed Kalman filtering compared to Fourier domain preconditioned conjugate gradient

    E-Print Network [OSTI]

    Greer, Julia R.

    Distributed Kalman filtering compared to Fourier domain preconditioned conjugate gradient for laser of the tomography problem. The second algorithm is the distributed Kalman filter (DKF) developed by Massioni et al

  6. Colour Gradients in the Optical and Near-IR

    E-Print Network [OSTI]

    Roelof S. de Jong

    1995-09-01T23:59:59.000Z

    For many years broadband colours have been used to obtain insight into the contents of galaxies, in particular to estimate stellar and dust content. Broadband colours are easy to obtain for large samples of objects, making them ideal for statistical studies. In this paper I use the radial distribution of the colours in galaxies, which gives more insight into the local processes driving the global colour differences than integrated colours. Almost all galaxies in my sample of 86 face-on galaxies become systematically bluer with increasing radius. The radial photometry is compared to new dust extinction models and stellar population synthesis models. This comparison shows that the colour gradients in face-on galaxies are best explained by age and metallicity gradients in the stellar populations and that dust reddening plays a minor role. The colour gradients imply $M/L$ gradients, making the `missing light' problem as derived from rotation curve fitting even worse.

  7. Field Investigations And Temperature-Gradient Drilling At Marine...

    Open Energy Info (EERE)

    Investigations And Temperature-Gradient Drilling At Marine Corps Air-Ground Combat Center (Mcagcc), Twenty-Nine Palms, Ca Jump to: navigation, search OpenEI Reference LibraryAdd to...

  8. Optimization Online - A conjugate-gradient based approach for ...

    E-Print Network [OSTI]

    Fredrik Carlsson

    2008-02-29T23:59:59.000Z

    Feb 29, 2008 ... In particular, it is noted that with a bound on the two-norm of the columns, the method is equivalent to the conjugate-gradient method. Further ...

  9. Function of the anterior gradient protein family in cancer 

    E-Print Network [OSTI]

    Fourtouna, Argyro

    2009-01-01T23:59:59.000Z

    Proteomic technologies verified Anterior Gradient 2, AGR-2, as a protein over-expressed in human cancers, including breast, prostate and oesophagus cancers, with the ability to inhibit the tumour suppressor protein p53. AGR-2 gene is a hormone...

  10. Energy Flow in Extended Gradient Partial Differential Equations

    E-Print Network [OSTI]

    Energy Flow in Extended Gradient Partial Differential Equations Th. Gallay S. Slijepâ??atiment 425 BijeniŸcka 30 F­91405 Orsay, France 10000 Zagreb, Croatia Thierry.Gallay@math.u­psud.fr slijepce

  11. A Nonlinear Conjugate Gradient Algorithm with An Optimal Property ...

    E-Print Network [OSTI]

    2011-06-15T23:59:59.000Z

    State Key Laboratory of Scientific and Engineering Computing, ..... To establish a basic property for the family of conjugate gradient methods (1.3), (2.11) and ...... of Engineering Economic Systems, Stanford University, Stanford, Calif., 1972. 23

  12. Spatial gradient of protein phosphorylation underlies replicative bacterium

    E-Print Network [OSTI]

    Chen, Y. Erin

    Spatial asymmetry is crucial to development. One mechanism for generating asymmetry involves the localized synthesis of a key regulatory protein that diffuses away from its source, forming a spatial gradient. Although ...

  13. Thermal Gradient Holes At Lightning Dock Geothermal Area (Arnold...

    Open Energy Info (EERE)

    DOE-funding Unknown Exploration Basis Known shallow hot spot in Animas Valley Notes Four thermal gradient holes were authorized to be drilled by AMEX, but no results were...

  14. Solar Neutrinos at Super-Kamiokande for Super-Kamiokande collaboration

    E-Print Network [OSTI]

    Tokyo, University of

    1 =1pc #12; 2 Solar Neutrinos at Super-Kamiokande K.Inoue a for Super-Kamiokande collaboration-cho, Yoshiki-gun, Gifu 506-12, Japan A huge ring imaging water Cherenkov detector, super-Kamiokande, has statistics and high precision spectrum and day/night ux measurement. Super-Kamiokande is accumulating 8 B

  15. Detection of the 6 November 1997 Ground Level Event by Abe D. Falcone, for Milagro Collaboration

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Collaboration University of New Hampshire, Space Science Center, Morse Hall, Durham, NH 03824 USA Abstract. Solar Energetic Particles (SEPs) with energies exceeding 10 GeV associated with the 6 November 1997 for observing very high energy gamma ray sources, can also be used to study the Sun. Milagrito, which operated

  16. Detection of 6 November 1997 Ground Level Event by for Milagro collaboration

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    collaboration 1 Space Science Center, University of New Hampshire, Durham, NH 03824 USA Abstract Solar Energetic Particles from the 6 November 1997 solar flare/CME(coronal mass ejection) with energies exceeding 10 GeV. The Milagro observatory, a ground based water Cherenkov detector designed for observing very high energy gamma

  17. DOE to Launch Collaborative Effort with Industry to Improve Natural Gas Systems

    Broader source: Energy.gov [DOE]

    DOE will launch a collaborative effort with industry to evaluate and scope high-impact manufacturing R&D to improve natural gas systems efficiency and leak reduction. The goal of this effort is to establish an advanced manufacturing initiative. AMO will lead this effort.

  18. EXTERNAL MENTORS AND COLLABORATORS PROGRAM -2015 The SU ADVANCE External Mentors and Collaborators Program creates opportunity for women in

    E-Print Network [OSTI]

    Doyle, Robert

    EXTERNAL MENTORS AND COLLABORATORS PROGRAM - 2015 The SU ADVANCE External Mentors universities. Mentors and collaborators will provide assistance, facilitate research efforts, and, where appropriate, be themselves examples of accomplished, senior women role models. Selected mentors

  19. Accounting for the Change in the Gradient: Health Inequality among Infants

    E-Print Network [OSTI]

    Lin, Wanchuan

    2006-01-01T23:59:59.000Z

    R. 1985. “Social Class Inequality in Mortality from 1921 toin the Gradient: Health Inequality Among Infants Wanchuanin the Gradient: Health Inequality Among Infants * Wanchuan

  20. Measurements of aerosol thermophoretic deposition: Transition with temperature gradient

    SciTech Connect (OSTI)

    Varma, A.; Tompson, R.V.; Loyalka, S.K. [Univ. of Missouri, Columbia, MO (United States)

    1995-12-31T23:59:59.000Z

    Thermophoresis is the motion of aerosol particles due to a temperature gradient in the suspending gas. The thermophoretic velocity V{sub T} is expressed as: where a {alpha} = thermal diffusivity v = kinematic viscosity H= Pr K Pr = Prandtl number K = dimensionless coefficient that is a function of several parameters (particle radius, thermal conductivity, gas properties, gas surface interactions). This report describes measurements of the effects of temperature gradients on the deposition of polystyrene latex particles.

  1. A Spectral Conjugate Gradient Method for Unconstrained Optimization

    SciTech Connect (OSTI)

    Birgin, E. G. [Department of Computer Science, IME-USP, University of Sao Paulo, Rua do Matao, 1010 - Cidade Universitaria, 05508-900 Sao Paulo SP (Brazil)], E-mail: egbirgin@ime.usp.br; Martinez, J. M. [Department of Applied Mathematics, IMECC-UNICAMP, University of Campinas, CP 6065, 13081-970 Campinas SP (Brazil)], E-mail: martinez@ime.unicamp.br

    2001-07-01T23:59:59.000Z

    A family of scaled conjugate gradient algorithms for large-scale unconstrained minimization is defined. The Perry, the Polak-Ribiere and the Fletcher-Reeves formulae are compared using a spectral scaling derived from Raydan's spectral gradient optimization method. The best combination of formula, scaling and initial choice of step-length is compared against well known algorithms using a classical set of problems. An additional comparison involving an ill-conditioned estimation problem in Optics is presented.

  2. Reduction of particle deposition on substrates using temperature gradient control

    DOE Patents [OSTI]

    Rader, Daniel J. (Albuquerque, NM); Dykhuizen, Ronald C. (Albuquerque, NM); Geller, Anthony S. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    A method of reducing particle deposition during the fabrication of microelectronic circuitry is presented. Reduction of particle deposition is accomplished by controlling the relative temperatures of various parts of the deposition system so that a large temperature gradient near the surface on which fabrication is taking place exists. This temperature gradient acts to repel particles from that surface, thereby producing cleaner surfaces, and thus obtaining higher yields from a given microelectronic fabrication process.

  3. Mass Function Gradients and the Need for Dark Matter

    E-Print Network [OSTI]

    Jason A. Taylor

    1998-03-05T23:59:59.000Z

    There is substantial evidence that the initial mass function (IMF) may be a function of the local star formation conditions. In particular, the IMF is predicted to flatten with increasing local luminosity density, with the formation of massive stars being preferentially enhanced in brighter regions. If IMF gradients are general features of galaxies, several previous astrophysical measurements, such as the surface mass densities of spirals (obtained assuming constant mass to light ratios), were plagued by substantial systematic errors. In this Letter, calculations which account for possible IMF gradients are presented of surface densities of spiral galaxies. Compared to previous estimates, the mass densities corrected for IMF gradients are higher in the outer regions of the disks. For a model based on the Milky Way but with an IMF scaled according to R136, the rotation curve without the traditional dark halo component falls with Galactocentric radius, though slower than it would without IMF gradients. For a second model of the Milky Way in which the IMF gradient is increased by 50%, the rotation curve is approximately flat in the outer disk, with a rotational velocity below ~220 km/s only before the traditional dark halo component is added. These results, if generalizable to other galaxies, not only call into question the assertion that dark matter halos are compatible with the flat rotation curves of spiral galaxies, but also may clarify our understanding of a wide variety of other astrophysical phenomena such as the G-dwarf problem, metallicity gradients, and the Tully-Fisher relation.

  4. Development of Ti/Ti{sub 3}Sn functionally gradient material produced by eutectic bonding method

    SciTech Connect (OSTI)

    Kirihara, S.; Takeda, M.; Tsujimoto, T. [Ibaraki Univ., Hitachi (Japan). Faculty of Engineering] [Ibaraki Univ., Hitachi (Japan). Faculty of Engineering

    1996-07-15T23:59:59.000Z

    Although many materials which have a single function have been developed, future needs are anticipated to include materials which have various functions. A functionally gradient material (FGM) which has characteristics of two different materials is a promising candidate for multi-functional material. The present methods for production of FGM, however, are very complicated and costly. In this study the authors answer the serious problem of high production cost by fabricating the FGM by a eutectic bonding method. This fabrication method includes structural control of FGM by changing the cooling process. They describe Ti/Ti{sub 3}Sn FGM obtained by the eutectic bonding method, and tell how the structure of its composition gradient part is changed by controlling the cooling process.

  5. Imaging diffusion with non-uniform B{sub 1} gradients.

    SciTech Connect (OSTI)

    Woelk, K.

    1998-01-30T23:59:59.000Z

    Rotating-frame imaging with the mathematically well-defined, non-constant magnetic field gradient of toroid cavity detectors represents a new technique to evaluate diffusion in solids, fluids or mixed-phase systems. While conventional NMR methods to measure diffusion utilize constant magnetic field gradients and, therefore, constant k-space wave numbers across the sample volume, the hyperbolic B{sub 1} fields of toroid cavity detectors exhibit large ranges of wave numbers radially distributed around the central conductor. As a consequence, signal amplitudes decay depending on the radial distance from the center axis of the torus. Applying a numerical finite-difference procedure to solve partial differential transport equations makes it possible not only to determine diffusion in toroid detectors to a high precision but also to include and accurately reproduce transport phenomena at or through singularities, such as phase transitions, membranes or impermeable boundaries.

  6. Study of Turbulent Fluctuations Driven by the Electron Temperature Gradient in the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    Mazzucato, E.; Bell, R. E.; Ethier, S.; Hosea, J. C.; Kaye, S. M.; LeBlanc, B. P.; Lee, W. W.; Ryan, P. M.; Smith, D. R.; Wang, W. X.; Wilson, J. R.

    2009-03-26T23:59:59.000Z

    Various theories and numerical simulations support the conjecture that the ubiquitous problem of anomalous electron transport in tokamaks may arise from a short-scale turbulence driven by the electron temperature gradient. To check whether this turbulence is present in plasmas of the National Spherical Torus Experiment (NSTX), measurements of turbulent fluctuations were performed with coherent scattering of electromagnetic waves. Results from plasmas heated by high harmonic fast waves (HHFW) show the existence of density fluctuations in the range of wave numbers k??e=0.1-0.4, corresponding to a turbulence scale length of the order of the collisionless skin depth. Experimental observations and agreement with numerical results from the linear gyro-kinetic GS2 code indicate that the observed turbulence is driven by the electron temperature gradient. These turbulent fluctuations were not observed at the location of an internal transport barrier driven by a negative magnetic shear.

  7. Strategic Nuclear Research Collaboration - FY99 Annual Report

    SciTech Connect (OSTI)

    T. J. Leahy

    1999-07-01T23:59:59.000Z

    The Idaho National Engineering and Environmental Laboratory (INEEL) has created the Strategic Nuclear Research Collaboration. The SNRC brings together some of America's finest laboratory and university nuclear researchers in a carefully focused research program intended to produce ''breakthrough'' solutions to the difficult issues of nuclear economics, safety, non-proliferation, and nuclear waste. This integrated program aims to address obstacles that stand in the way of nuclear power development in the US These include fuel cycle concerns related to waste and proliferation, the need for more efficient regulatory practices, and the high cost of constructing and operating nuclear power plants. Funded at an FY99 level of $2.58M, the SNRC is focusing the efforts of scientists and engineers from the INEEL and the Massachusetts Institute of Technology to solve complex nuclear energy challenges in a carefully chosen, integrated portfolio of research topics. The result of this collaboration will be research that serves as a catalyst for future direct-funded nuclear research and technology development and which preserves and enhances the INEEL's role as America's leading national laboratory for nuclear power research. In its first year, the SNRC has focused on four research projects each of which address one or more of the four issues facing further nuclear power development (economics, safety, waste disposition and proliferation-resistance). This Annual Report describes technical work and accomplishments during the first year of the SNRC's existence.

  8. Research collaboration opportunities at Lawrence Livermore National Laboratory

    SciTech Connect (OSTI)

    Budwine, C.M.

    1996-09-01T23:59:59.000Z

    The Lawrence Livermore National Laboratory (LLNL) is a major research facility within the Department of Energy (DOE) complex. LLNL`s traditional mission is in Defense Programs, including a significant effort in non-proliferation and arms control. In terms of disciplinary areas, over 50% of our present research efforts are in the fields of large-scale computing, high energy-density physics, energy and environmental sciences, engineering, materials research, manufacturing, and biotechnology. The present decade presents new challenges to LLNL. Many factors have influenced us in modifying our research approach. The main driver is the realization that many scientific problems in our mission areas can best be solved by collaborative teams of experts. At LLNL we excel in physical sciences, but we need the expertise of many others, beyond our established areas of expertise. For example, to find an acceptable solution to reduce earthquake damage requires contributions from engineering, soil mechanics, hydrology, materials sciences, Geosciences, computer modeling, economics, law, and political science. In the pursuit of our mission goals, we are soliciting increased research collaborations with university faculty and students. The scientific and national security challenges facing us and our nation today are unprecedented. Pooling talents from universities, other research organizations, and the national laboratories will be an important approach to finding viable solutions.

  9. A Path to Collaborative Strategic Learning

    SciTech Connect (OSTI)

    Nancy M. Carlson

    2003-10-01T23:59:59.000Z

    Collaborative learning is critical for the future of any organization and must align with the strategic organizational processes that result in products valued by others. To discover these processes, proposal preparation is explored using topic-oriented ethnography, grounded theory, and an innovative addition to qualitative interviewing, called metainquiry. Using interview data from editors, graphic artists, text processors, scientists, engineers, and technical managers, substantive theory emerges. The research discovers the five essential processes of owning, visioning, reviewing, producing, and contributing needed for organizational strategic learning to occur. The dimensions of these processes are made explicit and can be used to gauge the health of any organization. The substantive theory also provides insight into the ability of collaborative learning to evolve, flourish, and adapt to the strategic advantage of the organization. Lastly, actionable goals with ten essential elements emerge that link owning, visioning, reviewing, producing, and contributing as a path for all organizations to follow to promote collaborative learning communities and enhance their competitive advantage.

  10. Major transitions in evolution linked to thermal gradients above hydrothermal vents

    E-Print Network [OSTI]

    Anthonie W. J. Muller

    2012-12-03T23:59:59.000Z

    The emergence of the main divisions of today's life: (1) unicellular prokaryotes, (2) unicellular eukaryotes, (3) multicellular eukaryotes, and (4) metazoans, are examples of the--still unexplained--major transitions in evolution. Regarding the origin of life, I have proposed that primordial life functioned as heat engine (thermosynthesis) while thermally cycled in convecting volcanic hot springs. Here I argue for a role of thermal gradients above submarine hydrothermal vents (SHV) in several major transitions. The last decade has witnessed the emergence of phononics, a novel discipline in physics based on controlled heat transport in thermal gradients. It builds thermal analogs to electronic devices: the thermal diode, the thermal transistor, the thermal switch, the thermal amplifier, the thermal memory--the thermal computer has been proposed. Encouraged by (1) the many similarities between microtubules (MT) and carbon nanotubes, which have a very high thermal conductivity, and (2) the recent discovery of a silk protein which also has a very high thermal conductivity, I combine and extend the mentioned ideas, and propose the general conjecture that several major transitions of evolution were effected by thermal processes, with four additional partial conjectures: (1) The first organisms used heat engines during thermosynthesis in convection cells; (2) The first eukaryotic cells used MT during thermosynthesis in the thermal gradient above SHV; (3) The first metazoans used transport of water or in water during thermosynthesis above SHV under an ice-covered ocean during the Gaskiers Snowball Earth; and (4) The first mammalian brain used a thermal machinery based on thermal gradients in or across the cortex. When experimentally proven these conjectures, which are testable by the methods of synthetic biology, would significantly enhance our understanding of life.

  11. Support structure design of the Nb?Sn quadrupole for the high luminosity LHC

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

    Juchno, M. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Anerella, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ambrosio, G. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Cheng, D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Felice, H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ferracin, P. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Perez, J. C. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Prin, H. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Schmalzle, J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-06-01T23:59:59.000Z

    New low-? quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb?Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of the detailed 3D numerical analysis performed in preparation for the first short model test.

  12. Support structure design of the Nb?Sn quadrupole for the high luminosity LHC

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

    Juchno, M.; Anerella, M.; Ambrosio, G.; Cheng, D.; Felice, H.; Ferracin, P.; Perez, J. C.; Prin, H.; Schmalzle, J.

    2015-06-01T23:59:59.000Z

    New low-? quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb?Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of themore »detailed 3D numerical analysis performed in preparation for the first short model test.« less

  13. Environmental regulation of carbon isotope composition and crassulacean acid metabolism in three plant communities along a water availability gradient

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    gradient Á Tissue acidity Á Yucatan Introduction Crassulacean acid metabolism (metabolism in three plant communities along a water availability gradient

  14. Scalar gradient behaviour in MILD combustion

    E-Print Network [OSTI]

    Minamoto, Y.; Swaminathan, N.

    2013-10-22T23:59:59.000Z

    the exhaust gas recircula- tion (EGR) techniques. The recirculation can be either internal or external to the combustor and external EGR is common in heavy duty diesel engines and internal recirculation is common in furnaces. At very high EGR rate, the oxygen...

  15. Evolutionary and Gradient-Based Algorithms for Lennard-Jones Cluster Optimization

    E-Print Network [OSTI]

    Schraudolph, Nicol N.

    gradient method, while Section 3 shows how the asynchronous conjugate gradient method compares and randomized gradient methods with respect to their global search behavior. The randomized gradient method.g., conjugate gra- dient method) is started. With the local minima in- formation, the search is continued

  16. The Solution of Systems of Linear Equations using the Conjugate Gradient Method

    E-Print Network [OSTI]

    Schneider, Jean-Guy

    The Solution of Systems of Linear Equations using the Conjugate Gradient Method on the Parallel gradient solver on the SPMD­programmable MUSIC­system. We outline the conjugate gradient method, give­associativity of the floating point addition. We investi­ gate the speed of convergence of the conjugate gradient method

  17. Newton-conjugate-gradient methods for solitary wave computations Jianke Yang

    E-Print Network [OSTI]

    Yang, Jianke

    Newton-conjugate-gradient methods for solitary wave computations Jianke Yang Department's method Conjugate-gradient methods a b s t r a c t In this paper, the Newton-conjugate-gradient methods the linearization operator is self-adjoint, the preconditioned conjugate-gradient method is pro- posed to solve

  18. A NONLINEAR CONJUGATE GRADIENT METHOD WITH A STRONG GLOBAL CONVERGENCE PROPERTY

    E-Print Network [OSTI]

    Yuan, Ya-xiang

    A NONLINEAR CONJUGATE GRADIENT METHOD WITH A STRONG GLOBAL CONVERGENCE PROPERTY Y. H. DAI AND Y­182 Abstract. Conjugate gradient methods are widely used for unconstrained optimization, especially large scale gradient methods. This paper presents a new version of the conjugate gradient method, which converges

  19. Algorithm 851: CG DESCENT, a Conjugate Gradient Method with Guaranteed Descent

    E-Print Network [OSTI]

    Zhang, Hongchao

    Algorithm 851: CG DESCENT, a Conjugate Gradient Method with Guaranteed Descent WILLIAM W. HAGER In Hager and Zhang [2005] we introduce a new nonlinear conjugate gradient method for solving con- jugate gradient research. The iterates xk, k 0, in conjugate gradient methods satisfy

  20. Efficient Computation of Entropy Gradient for Semi-Supervised Conditional Random Fields

    E-Print Network [OSTI]

    McCallum, Andrew

    gradient that is significantly more efficient--having the same asymptotic time complexity as su- pervised

  1. Quasi-linear gradients for capillary liquid chromatography with mass and tandem mass

    E-Print Network [OSTI]

    Dabiri, John O.

    Gradient elution, capillary liquid chromatography mass spectrometry was performed with linear, static the use of additional valves, mixers, pumps or software. It took less than 10 minutes to form a gradient-line as static gradients.12­14 The technique of forming static gradients was first proposed by Ishii and co

  2. X-band EPR imaging as a tool for gradient dose reconstruction in irradiated bones

    SciTech Connect (OSTI)

    Leveque, Philippe; Godechal, Quentin; Bol, Anne; Trompier, Francois; Gallez, Bernard [Biomedical Magnetic Resonance Unit, Universite catholique de Louvain, B-1200 Brussels (Belgium); Molecular Imaging and Experimental Radiotherapy Unit, Universite catholique de Louvain, B-1200 Brussels (Belgium); Institut de Surete Nucleaire et de Radioprotection, F-92262 Fontenay-aux-Roses (France); Biomedical Magnetic Resonance Unit, Universite catholique de Louvain, B-1200 Brussels (Belgium)

    2009-09-15T23:59:59.000Z

    Purpose: Various tools are currently available for dose reconstruction in individuals after accidental exposure to ionizing radiation. Among the available biological analyses, Monte Carlo simulations, and biophysical methods, such as electron paramagnetic resonance (EPR), the latter has proved its usefulness for retrospective dosimetry. Although EPR spectroscopy is probably the most sensitive technique, it does not provide spatial dosimetric data. This information is, however, highly desirable when steep dose gradient irradiations are involved. The purpose of this work was to explore the possibilities of EPR imaging (EPRI) for spatial dose reconstruction in irradiated biological material. Methods: X-band EPRI was used to reconstruct ex vivo the relative dose distribution in human bone samples and hydroxyapatite phantoms after irradiation with brachytherapy seeds or x rays. Three situations were investigated: Homogeneous, stepwise gradient, and continuous gradient irradiation. Results: EPRI gave a faithful relative spin density distribution in bone samples and in hydroxyapatite phantoms. Measured dose ratios were in close agreement with the actual delivered dose ratios. EPRI was able to distinguish the dose gradients induced by two different sources ({sup 125}I and {sup 192}Ir). However, the measured spatial resolution of the system was 1.9 mm and this appeared to be a limiting factor. The method could be improved by using new signal postprocessing strategies. Conclusions: This study demonstrates that EPRI can be used to assess the regional relative dose distribution in irradiated bone samples. The method is currently applicable to ex vivo measurements of small size samples with low variation in tissue density but is likely to be adapted for in vivo application using L-band EPRI.

  3. International Collaboration on CO2 Sequestration

    SciTech Connect (OSTI)

    Peter H. Israelsson; E. Eric Adams

    2007-06-30T23:59:59.000Z

    On December 4, 1997, the US Department of Energy (USDOE), the New Energy and Industrial Technology Development Organization of Japan (NEDO), and the Norwegian Research Council (NRC) entered into a Project Agreement for International Collaboration on CO{sub 2} Ocean Sequestration. Government organizations from Japan, Canada, and Australia, and a Swiss/Swedish engineering firm later joined the agreement, which outlined a research strategy for ocean carbon sequestration via direct injection. The members agreed to an initial field experiment, with the hope that if the initial experiment was successful, there would be subsequent field evaluations of increasingly larger scale to evaluate environmental impacts of sequestration and the potential for commercialization. The evolution of the collaborative effort, the supporting research, and results for the International Collaboration on CO{sub 2} Ocean Sequestration were documented in almost 100 papers and reports, including 18 peer-reviewed journal articles, 46 papers, 28 reports, and 4 graduate theses. These efforts were summarized in our project report issued January 2005 and covering the period August 23, 1998-October 23, 2004. An accompanying CD contained electronic copies of all the papers and reports. This report focuses on results of a two-year sub-task to update an environmental assessment of acute marine impacts resulting from direct ocean sequestration. The approach is based on the work of Auerbach et al. [6] and Caulfield et al. [20] to assess mortality to zooplankton, but uses updated information concerning bioassays, an updated modeling approach and three modified injection scenarios: a point release of negatively buoyant solid CO{sub 2} hydrate particles from a moving ship; a long, bottom-mounted diffuser discharging buoyant liquid CO{sub 2} droplets; and a stationary point release of hydrate particles forming a sinking plume. Results suggest that in particular the first two discharge modes could be successfully designed to largely avoid zooplankton mortality. Sub-lethal and ecosystem effects are discussed qualitatively, but not analyzed quantitatively.

  4. Security tasks are highly interdependent.

    E-Print Network [OSTI]

    Motivation Security tasks are highly interdependent. To improve security tools, we need to understand how security practitioners collaborate in their organizations. Security practitioners in context Exchange of Information Develop security tools that: · Integrate information from different communication

  5. Property:Collaborating Organizations | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,PillarPublicationType Jump to: navigation, search ThisCollaborating Organizations

  6. Collaborative Mathematical Workbench Eliot Feibush, Matthew Milano,

    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 Office511041clothAdvanced Materials Advanced. C o w l i tCollaboration March 16, 2010 During the courseBenjamin

  7. Collaborative Military Vehicle Design | GE Global Research

    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 Office511041clothAdvanced Materials Advanced. C o w l i tCollaboration March 16, 2010 During the

  8. Collaborative vision, saving sight | ornl.gov

    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 Office511041clothAdvanced Materials Advanced. C o w l i tCollaboration March 16, 2010 During

  9. The MicroBooNE Experiment - Collaboration

    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 The NIF andPoints of FasterdataCollaboration (*) The

  10. SOLPOND: a simulation program for salinity gradient solar ponds

    SciTech Connect (OSTI)

    Henderson, J.; Leboeuf, C.M.

    1980-01-01T23:59:59.000Z

    A computer simulation design tool was developed to simulate dynamic thermal performance for salinity gradient solar ponds. Dynamic programming techniques allow the user significant flexibility in analyzing pond performance under realistic load and weather conditions. Finite element techniques describe conduction heat transfer through the pond, earth, and edges. Results illustrate typical thermal performance of salinity gradient ponds. Sensitivity studies of salty pond thermal performance with respect to geometry, load, and optical transmission are included. Experimental validation of the program with an operating pond is also presented.

  11. Radial gradients and metallicities in the galactic disk

    E-Print Network [OSTI]

    W. J. Maciel

    2000-12-08T23:59:59.000Z

    Radial O/H abundance gradients derived from HII regions, hot stars and planetary nebulae are combined with [Fe/H] gradients from open cluster stars in order to derive an independent [O/Fe] x [Fe/H] relation for the galactic disk. A comparison of the obtained relation with recent observational data and theoretical models suggests that the [O/Fe] ratio is not higher than [O/Fe] ~ 0.4, at least within the metallicity range of the considered samples.

  12. Nonlinear elastic free energies and gradient Young-Gibbs measures

    E-Print Network [OSTI]

    Roman Kotecký; Stephan Luckhaus

    2012-06-26T23:59:59.000Z

    We investigate, in a fairly general setting, the limit of large volume equilibrium Gibbs measures for elasticity type Hamiltonians with clamped boundary conditions. The existence of a quasiconvex free energy, forming the large deviations rate functional, is shown using a new interpolation lemma for partition functions. The local behaviour of the Gibbs measures can be parametrized by Young measures on the space of gradient Gibbs measures. In view of unboundedness of the state space, the crucial tool here is an exponential tightness estimate that holds for a vast class of potentials and the construction of suitable compact sets of gradient Gibbs measures.

  13. On Higuchi Ghosts and Gradient Instabilities in Bimetric Gravity

    E-Print Network [OSTI]

    Könnig, Frank

    2015-01-01T23:59:59.000Z

    We discuss the conditions to satisfy the Higuchi bound and to avoid gradient instabilities in the scalar sector for cosmological solutions in singly coupled bimetric gravity theories. We find that in expanding universes the ratio of the scale factors of the reference and observable metric has to increase at all times. This automatically implies a ghost-free helicity-2 sector and enforces a phantom Dark Energy. Furthermore, the condition for the absence of gradient instabilities in the scalar sector will be analyzed. Finally, we discuss whether cosmological solutions, including exotic evolutions like bouncing cosmologies, can exist, in which both the Higuchi ghost and scalar instabilities are absent at all times.

  14. Gradient isolator for flow field of fuel cell assembly

    DOE Patents [OSTI]

    Ernst, William D. (Troy, NY)

    1999-01-01T23:59:59.000Z

    Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions.

  15. Velocity bunching in travelling wave accelerator with low acceleration gradient

    E-Print Network [OSTI]

    Huang, Rui-Xuan; Li, Wei-Wei; Jia, Qi-Ka

    2013-01-01T23:59:59.000Z

    We present the analytical and simulated results concerning the influences of the acceleration gradient in the velocity bunching process, which is a bunch compression scheme that uses a traveling wave accelerating structure as a compressor. Our study shows that the bunch compression application with low acceleration gradient is more tolerant to phase jitter and more successful to obtain compressed electron beam with symmetrical longitudinal distribution and low energy spread. We also present a transverse emittance compensation scheme to compensate the emittance growth caused by the increasing of the space charge force in the compressing process that is easy to be adjusted for different compressing factors.

  16. Discontinuous Galerkin finite element methods for gradient plasticity.

    SciTech Connect (OSTI)

    Garikipati, Krishna. (University of Michigan, Ann Arbor, MI); Ostien, Jakob T.

    2010-10-01T23:59:59.000Z

    In this report we apply discontinuous Galerkin finite element methods to the equations of an incompatibility based formulation of gradient plasticity. The presentation is motivated with a brief overview of the description of dislocations within a crystal lattice. A tensor representing a measure of the incompatibility with the lattice is used in the formulation of a gradient plasticity model. This model is cast in a variational formulation, and discontinuous Galerkin machinery is employed to implement the formulation into a finite element code. Finally numerical examples of the model are shown.

  17. Gradients of meteorological parameters in convective and nonconvective areas

    E-Print Network [OSTI]

    McCown, Milton Samuel

    1976-01-01T23:59:59.000Z

    . SYNOPTIC CONDITIONS 4. STRATIFICATION OF DATA 5. COMPUTATIONAL PROCEDURES 21 25 a. Gridding of rawinsonde data 25 b. Gradients 26 5'' lp t* 27 RESULTS 29 a. Gradients 29 1) Convective areas 29 2) Nonconvective areas 31 3) Combined areas 33 vi... air turbulence. By using airplane data from over the western United States, Scoggins (1975) has shown that CAT at 300 mb occurred 71% of the time when the magnitude of the vector horizontal wind shear -5 -1 exceeded 4. 5 x 10 sec . The horizontal...

  18. Gradient isolator for flow field of fuel cell assembly

    DOE Patents [OSTI]

    Ernst, W.D.

    1999-06-15T23:59:59.000Z

    Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions. 4 figs.

  19. The Effects of Presence on Small Group Collaboration and Interaction in a Collaborative Virtual Environment

    E-Print Network [OSTI]

    Blake, Edwin

    Environment Cathryn Johns, Marc Daya, Duncan Sellars, Juan Casanueva, Edwin Blake Collaborative Visual and computer graphics technology, collabora- tive virtual environments are becoming a feasi- ble way to address feeling of being in a virtual environment) and co-presence (the feeling that other people

  20. The Diesel Combustion Collaboratory: Combustion Researchers Collaborating over the Internet

    SciTech Connect (OSTI)

    C. M. Pancerella; L. A. Rahn; C. Yang

    2000-02-01T23:59:59.000Z

    The Diesel Combustion Collaborator (DCC) is a pilot project to develop and deploy collaborative technologies to combustion researchers distributed throughout the DOE national laboratories, academia, and industry. The result is a problem-solving environment for combustion research. Researchers collaborate over the Internet using DCC tools, which include: a distributed execution management system for running combustion models on widely distributed computers, including supercomputers; web-accessible data archiving capabilities for sharing graphical experimental or modeling data; electronic notebooks and shared workspaces for facilitating collaboration; visualization of combustion data; and video-conferencing and data-conferencing among researchers at remote sites. Security is a key aspect of the collaborative tools. In many cases, the authors have integrated these tools to allow data, including large combustion data sets, to flow seamlessly, for example, from modeling tools to data archives. In this paper the authors describe the work of a larger collaborative effort to design, implement and deploy the DCC.

  1. A case study of collaborative facilities use in engineering design

    SciTech Connect (OSTI)

    Monroe, Laura M [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    In this paper we describe the use of visualization tools and facilities in the collaborative design of a replacement weapons system, the Reliable Replacement Warhead. We used not only standard collaboration methods but also a range of visualization software and facilities to bring together domain specialists from laboratories across the country to collaborate on the design and integrate this disparate input early in the design.

  2. Collaborative Visualization for Large-Scale Accelerator Electromagnetic Modeling

    SciTech Connect (OSTI)

    Schussman, Greg; /SLAC

    2010-08-25T23:59:59.000Z

    In the Phase I SBIR we proposed a ParaView-based solution to provide an environment for individuals to actively collaborate in the visualization process. The technical objectives of Phase I were: (1) to determine the set of features required for an effect collaborative system; (2) to implement a two-person collaborative prototype; and (3) to implement key collaborative features such as control locking and annotation. Accordingly, we implemented a ParaView-based collaboration prototype with support for collaborating with up to four simultaneous clients. We also implemented collaborative features such as control locking, chatting, annotation etc. Due to in part of the flexibility provided by the ParaView framework and the design features implemented in the prototype, we were able to support collaboration with multiple views, instead of a simple give as initially proposed in Phase I. In this section we will summarize the results we obtained during the Phase I project. ParaView is complex, scalable, client-server application framework built on top of the VTK visualization engine. During the implementation of the Phase I prototype, we realized that the ParaView framework naturally supports collaboration technology; hence we were able to go beyond the proposed Phase I prototype in several ways. For example, we were able to support for multiple views, enable server-as well as client-side rendering, and manage up to four heterogeneous clients. The success we achieved with Phase I clearly demonstrated the technical feasibility of the ParaView based collaborative framework we are proposing in the Phase II effort. We also investigated using the web browser as one of the means of participating in a collaborative session. This would enable non-visualization experts to participate in the collaboration process without being intimidated by a complex application such as ParaView. Hence we also developed a prototype web visualization applet that makes it possible for interactive visualization over the web.

  3. Center for Nanoscale Control of Geologic CO2 (EFRC) - Collaborators

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

    Collaborators Lawrence Berkeley National Laboratory (lead institution) Lawrence Berkeley National Lab logo Berkeley Lab is a multidisciplinary national laboratory that is home to...

  4. Bureau of Land Management, Colorado collaborate to advance efficient...

    Open Energy Info (EERE)

    Colorado collaborate to advance efficient geothermal development Jump to: navigation, search OpenEI Reference LibraryAdd to library Memorandum: Bureau of Land Management, Colorado...

  5. Communicating for Creative Success in Remote Collaborative Work

    E-Print Network [OSTI]

    Keske, Stephanie Lee

    2014-01-16T23:59:59.000Z

    among communication modalities for di erent types of communication: namely, asynchronous modalities are preferred for logistical communication and synchronous modalities are preferred for aesthetic communication. Collaboration using computer...

  6. A case study of collaborative facilities in engineering design

    SciTech Connect (OSTI)

    Monroe, Laura M [Los Alamos National Laboratory; Pugmire, David [ORNL

    2008-01-01T23:59:59.000Z

    In this paper we describe the use of visualization tools and facilities in the collaborative design of a replacement weapons system, the Reliable Replacement Warhead (RRW). We used not only standard collaboration methods but also a range of visualization software and facilities to bring together domain specialists from laboratories across the country to collaborate on the design and integrate this disparate input early in the design. This was the first time in U.S. weapons history that a weapon had been designed in this collaborative manner. Benefits included projected cost savings, design improvements and increased understanding across the project.

  7. actual collaboration support: Topics by E-print Network

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

    found to be useful. Keywords: Open Learner Models, Online Social Networks around their OLM and social interaction by using online social networks. In addition to collaboration...

  8. Sandia Energy - PV Performance Modeling Collaborative's New and...

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

    Modeling & Simulation Solar Newsletter Photovoltaic Systems Evaluation Laboratory (PSEL) PV Performance Modeling Collaborative's New and Improved Website Is Launched Previous Next...

  9. NREL Gearbox Reliability Collaborative Analysis Round Robin: Preprint

    SciTech Connect (OSTI)

    Oyague, F.; Butterfield, C. P.; Sheng, S.

    2009-05-01T23:59:59.000Z

    The Gearbox Reliability Collaborative is working to determine the causes and loading conditions that result in the premature failure of wind turbine gearboxes.

  10. EUCI Tribal and Indian Country Energy Development: Collaborating...

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

    provide practical tips for mutually beneficial collaboration between tribes and utility companies. The conference will focus on the fundamental concepts on how to network and...

  11. NETL-Led Laboratory-Industry-Academia Collaboration Is Accelerating...

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

    of successful, effective collaboration among government, industry, and academia. The heart of the initiative is the CCSI Toolset, a suite of computer models and computational...

  12. OMB and CEQ Joint Memorandum on Environmental Collaboration and...

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

    Joint Memorandum on Environmental Collaboration and Conflict Resolution This Office of Management and Budget (OMB) and Council on Environmental Quality (CEQ) joint memorandum...

  13. Identifying a Collaborating DOE Laboratory Scientist | U.S. DOE...

    Office of Science (SC) Website

    Identifying a Collaborating DOE Laboratory Scientist DOE Office of Science Graduate Student Research (SCGSR) Program SCGSR Home Eligibility Benefits Participant Obligations How to...

  14. Energy-Efficient GPGPU Architectures via Collaborative Compilation and Memristive

    E-Print Network [OSTI]

    Liebling, Michael

    Energy-Efficient GPGPU Architectures via Collaborative Compilation and Memristive Memory that exploit data-parallelism ­the most energy-efficient form of parallelism. Unfortunately, technology scaling

  15. U-012: BlackBerry Enterprise Server Collaboration Service Bug...

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

    Advisory ID: KB28524 SecurityTracker Alert ID: 1026179 CVE-2011-0290 IMPACT ASSESSMENT: Medium Discussion: A vulnerability exists in the BlackBerry Collaboration Service...

  16. Gearbox Reliability Collaborative Experimental Data Overview & Analysis (Presentation)

    SciTech Connect (OSTI)

    Oyague, F.

    2010-05-01T23:59:59.000Z

    This presentation details how wind turbine gearboxes fail to meet 20-year design life and how the Gearbox Reliability Collaborative (GRC) is addressing the challenges.

  17. Advanced Collaborative Emissions Study (ACES): Phase 2 Status...

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

    : Phase 2 Status Report Advanced Collaborative Emissions Study (ACES): Phase 2 Status Report Discusses status of ACES, a cooperative multi-party effort to characterize emissions...

  18. COP 18 Side Event: Advancing Collaborative Action for Low Emissions...

    Open Energy Info (EERE)

    Event: Advancing Collaborative Action for Low Emissions Development Jump to: navigation, search Low Emission Development Strategies Global Partnership Advancing climate-resilient,...

  19. The Advanced Collaborative Emissions Study Moving Forward with...

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

    Moving Forward with Assessing the Emissions and Health Effects of New Diesel Technology The Advanced Collaborative Emissions Study Moving Forward with Assessing the Emissions and...

  20. Real-time Collaborative Environments and the Grid

    E-Print Network [OSTI]

    Perkins, C.S.; Gharai, L.; Proceedings of the Workshop on Advanced Collaborative Environments (WACE'04), Nice, France, September 2004.; [More Details

    Perkins,C.S. Gharai,L. Proceedings of the Workshop on Advanced Collaborative Environments (WACE'04), Nice, France, September 2004.

  1. Turbulent electron transport in edge pedestal by electron temperature gradient turbulence

    SciTech Connect (OSTI)

    Singh, R. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Institute for Plasma Research, Bhat Gandhinagar, Gujarat 2382 428 (India); Jhang, Hogun [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)] [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); CMTFO and CASS, University of California, San Diego 92093-0424, California (United States)

    2013-11-15T23:59:59.000Z

    We present a model for turbulent electron thermal transport at the edge pedestal in high (H)-mode plasmas based on electron temperature gradient (ETG) turbulence. A quasi-linear analysis of electrostatic toroidal ETG modes shows that both turbulent electron thermal diffusivity and hyper-resistivity exhibits the Ohkawa scaling in which the radial correlation length of turbulence becomes the order of electron skin depth. Combination of the Ohkawa scales and the plasma current dependence results in a novel confinement scaling inside the pedestal region. It is also shown that ETG turbulence induces a thermoelectric pinch, which may accelerate the density pedestal formation.

  2. anion exchange high-performance: Topics by E-print Network

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

    Websites Summary: Abstract Current communications tools and libraries for high performance computing are designed' in our research and (2) high performance collaborative...

  3. A strong polynomial gradient algorithm in Linear Programming

    E-Print Network [OSTI]

    peter bruijs

    2015-03-31T23:59:59.000Z

    Page 1 ... Karmarkar don't have the strong characteristic. ... Probably he had no notion of the concept of a convex space, so that is what will have to be .... For the best direction that is left now, one has to exclude from the gradient c exactly and.

  4. Seasonal mass balance gradients in Norway L. A. Rasmussen1

    E-Print Network [OSTI]

    Rasmussen, L.A.

    16 Aug 05 Seasonal mass balance gradients in Norway L. A. Rasmussen1 and L. M. Andreassen2 1 Norwegian Water Resources and Energy Directorate (NVE) P. O. Box 5091 Majorstua, N-0301 Oslo, Norway in Norway exists in their profiles of both seasonal balances, winter bw(z) and summer bs(z). Unlike many

  5. The Urban Environmental Gradient: Anthropogenic Influences on the

    E-Print Network [OSTI]

    Georgia, through Atlanta, to the Gulf of Mexico and reflects a steep gradient in population density from as vehicular traffic. Introduction Many of the common anthropogenic pollution problems are focused in urban geographic areas. Suburbia does not contribute much by way of industrial pollution, but it does serve

  6. Gradient expansion of superhorizon perturbations in G-inflation

    SciTech Connect (OSTI)

    Frusciante, Noemi; Zhou, Shuang-Yong; Sotiriou, Thomas P., E-mail: nfruscia@sissa.it, E-mail: szhou@sissa.it, E-mail: sotiriou@sissa.it [SISSA and INFN Sezione di Trieste, Via Bonomea 265, 34136, Trieste (Italy)

    2013-07-01T23:59:59.000Z

    We develop the gradient expansion formalism for shift-symmetric Galileon-type actions. We focus on backgrounds that undergo inflation, work in the synchronous gauge, and obtain a general solution up to second order without imposing extra conditions at first order. The solution simplifies during the late stages of inflation. We also define a curvature perturbation conserved up to first order.

  7. Continuous Edge Gradient-Based Template Matching for Articulated

    E-Print Network [OSTI]

    Zachmann, Gabriel

    Zachmann IfI Technical Report Series IfI-09-01 #12;Impressum Publisher: Institut für Informatik, Technische (Technical Computer Science) Prof. Dr. Gabriel Zachmann (Computer Graphics) #12;Continuous Edge Gradient-Based Template Matching for Articulated Objects Daniel Mohr and Gabriel Zachmann Abstract Detection

  8. Computing several eigenpairs of Hermitian problems by conjugate gradient iterations

    SciTech Connect (OSTI)

    Ovtchinnikov, E.E. [Harrow School of Computer Science, University of Westminster, Watford Road, Northwick Park, London HA1 3TP (United Kingdom)], E-mail: e_ovtchinnikov@hotmail.com

    2008-11-20T23:59:59.000Z

    The paper is concerned with algorithms for computing several extreme eigenpairs of Hermitian problems based on the conjugate gradient method. We analyse computational strategies employed by various algorithms of this kind reported in the literature and identify their limitations. Our criticism is illustrated by numerical tests on a set of problems from electronic structure calculations and acoustics.

  9. GEOTHERMAL GRADIENT DATA FOR UTAH Robert E. Blackett

    E-Print Network [OSTI]

    Laughlin, Robert B.

    GEOTHERMAL GRADIENT DATA FOR UTAH by Robert E. Blackett February 2004 UTAH GEOLOGICAL SURVEY ­ 1:750,000 scale map, showing geology; thermal wells, springs, and geothermal areas; and locations available sources including the Southern Methodist University Geothermal Laboratory, U.S. Geological Survey

  10. BIOGEOCHEMICAL GRADIENTS AS A FRAMEWORK FOR UNDERSTANDING WASTE SITE EVOLUTION

    SciTech Connect (OSTI)

    Denham, M; Karen Vangelas, K

    2008-10-17T23:59:59.000Z

    The migration of biogeochemical gradients is a useful framework for understanding the evolution of biogeochemical conditions in groundwater at waste sites contaminated with metals and radionuclides. This understanding is critical to selecting sustainable remedies and evaluating sites for monitored natural attenuation, because most attenuation mechanisms are sensitive to geochemical conditions such as pH and redox potential. Knowledge of how gradients in these parameters evolve provides insights into the behavior of contaminants with time and guides characterization, remedy selection, and monitoring efforts. An example is a seepage basin site at the Savannah River Site in South Carolina where low-level acidic waste has seeped into groundwater. The remediation of this site relies, in part, on restoring the natural pH of the aquifer by injecting alkaline solutions. The remediation will continue until the pH up-flow of the treatment zone increases to an acceptable value. The time required to achieve this objective depends on the time it takes the trailing pH gradient, the gradient separating the plume from influxing natural groundwater, to reach the treatment zone. Predictions of this length of time will strongly influence long-term remedial decisions.

  11. Soil macroaggregate dynamics in a mountain spatial climate gradient

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Soil macroaggregate dynamics in a mountain spatial climate gradient Lauric Cécillon1,2,* , Nilvania://lauric.cecillon.free.fr/ Key words: Mountain soils; Climate change; Soil aggregation; Soil organic matter; Near infrared reflectance spectroscopy; Soil threats Biogeochemistry 97: 31-43 (2010) http://dx.doi.org/10.1007/s10533

  12. Scaling limits for gradient systems in random environment

    E-Print Network [OSTI]

    P. Goncalves; M. D. Jara

    2007-02-17T23:59:59.000Z

    For interacting particle systems that satisfies the gradient condition, the hydrodynamic limit and the equilibrium fluctuations are well known. We prove that under the presence of a symmetric random environment, these scaling limits also hold for almost every choice of the environment, with homogenized coefficients that does not depend on the particular realization of the random environment.

  13. Overfitting in Neural Nets: Backpropagation, Conjugate Gradient, and Early Stopping

    E-Print Network [OSTI]

    Caruana, Rich

    Overfitting in Neural Nets: Backpropagation, Conjugate Gradient, and Early Stopping Rich Caruana is that backprop nets with excess hidden units generalize poorly. We show that nets with excess capacity generalize) Regardless of size, nets learn task subcomponents in similar sequence. Big nets pass through stages similar

  14. SUBMIT TO IEEE TIP 1 Motion-Aware Gradient Domain

    E-Print Network [OSTI]

    O'Brien, James F.

    SUBMIT TO IEEE TIP 1 Motion-Aware Gradient Domain Video Composition Tao Chen, Jun-Yan Zhu, Ariel blending boundary based on a user provided blending trimap for the source video. Our approach extends mean performance. We also provide a user interface and source object positioning method that can efficiently deal

  15. A distributed accelerated gradient algorithm for distributed model predictive

    E-Print Network [OSTI]

    Como, Giacomo

    of hydro power plants is to manage the available water resources efficiently, while following an optimal is applied to the power reference tracking problem of a hydro power valley (HPV) system. The applied power control, Distributed optimization, Accelerated gradient algorithm, Model predictive control

  16. A study of microbend test by strain gradient plasticity

    E-Print Network [OSTI]

    Hsia, K Jimmy

    A study of microbend test by strain gradient plasticity W. Wanga , Y. Huangb, *, K.J. Hsiac , K with plastic deformation is on the order of microns. This size effect cannot be explained by classical plasticity theories since their constitutive relations do not have an intrinsic material length. Strain

  17. Treated Wastewater Effluent Reduces Sperm Motility Along an Osmolality Gradient

    E-Print Network [OSTI]

    Julius, Matthew L.

    of the Metropolitan Wastewater Treatment Plant, St. Paul, Minnesota, and from an upstream site on the MississippiTreated Wastewater Effluent Reduces Sperm Motility Along an Osmolality Gradient H. L. Schoenfuss Æ 2008 Ó Springer Science+Business Media, LLC 2008 Abstract Many toxic effects of treated wastewater

  18. SNL/VNIIEF Storage Monitoring Collaboration

    SciTech Connect (OSTI)

    Barkanov, Boris P.; Bartberger, Jack C.; Blagin, Sergei V.; Croessmann, C. Dennis; Gruda, Jeffrey D.; Lupsha, Vitali A.; Moroskin, Dimitri V.; Nilsen, Curt A.

    1999-07-12T23:59:59.000Z

    Sandia National Laboratories (SNL) and the Russian Federal Nuclear Center-All Russian Research Institute for Experimental Physics (VNIIEF)(also know as Arzamas-16) are collaborating on ways to assure the highest standards on safety, security, and international accountability of fissile material. This includes systems used to reduce the need for human access to fissile material, reduce radiation exposure, and provide prompt safety-related information, and provide continuous international accountability information while reducing the need for intrusive, on-site visits. This paper will report on the ongoing SNL/VNIIEF efforts to develop technologies and monitoring systems to meet these goals. Specific topics covered will include: the Smart Bolt tag/seal development, development and testing of electronic sensor platforms (U.S. T-1 ESP and VNIIEF Radio Tag) for monitoring and transportation applications, the ''Magazine-to-Magazine'' remote monitoring system field test, and the ''Facility-to-Facility'' storage monitoring system field trial.

  19. Performance of Nb3Sn Quadrupole Under High Stress

    SciTech Connect (OSTI)

    Felice, H.; Bajko, M.; Bingham, B.; Bordini, B.; Bottura, L.; Caspi, S.; Rijk, G. De; Dietderich, D.; Ferracin, P.; Giloux, C.; Godeke, A.; Hafalia, R.; Milanese, A.; Rossi, L.; Sabbi, G. L.

    2010-08-01T23:59:59.000Z

    Future upgrades of the Large Hadron Collider (LHC) will require large aperture and high gradient quadrupoles. Nb{sub 3}Sn is the most viable option for this application but is also known for its strain sensitivity. In high field magnets, with magnetic fields above 12 T, the Lorentz forces will generate mechanical stresses that may exceed 200 MPa in the windings. The existing measurements of critical current versus strain of Nb{sub 3}Sn strands or cables are not easily applicable to magnets. In order to investigate the impact of high mechanical stress on the quench performance, a series of tests was carried out within a LBNL/CERN collaboration using the magnet TQS03 (a LHC Accelerator Research Program (LARP) 1-meter long, 90-mm aperture Nb{sub 3}Sn quadrupole). The magnet was tested four times at CERN under various pre-stress conditions. The average mechanical compressive azimuthal pre-stress on the coil at 4.2 K ranged from 120 MPa to 200 MPa. This paper reports on the magnet performance during the four tests focusing on the relation between pre-stress conditions and the training plateau.

  20. Incorporating Learning Styles in a Computer-Supported Collaborative Learning

    E-Print Network [OSTI]

    Griffiths, Nathan

    they think and learn. Roschelle and Teasley focus more on the nature of interaction in collaborative learning a specific problem. Student reading groups for language learning courses are an example of learning groupsIncorporating Learning Styles in a Computer-Supported Collaborative Learning Model Shuangyan Liua

  1. MAOSIU SOLAR PHYSICS COLLABORATIONS R.J. Rutten

    E-Print Network [OSTI]

    Rutten, Rob

    MAO­SIU SOLAR PHYSICS COLLABORATIONS R.J. Rutten Sterrekundig Instituut Utrecht, Postbus 80 000, NL 3508 TA, Utrecht, The Netherlands e-mail: R.J.Rutten@astro.uu.nl The Kiev­Utrecht collaboration exciting research challenges which fit the Kiev­Utrecht expertise and interests. INTRODUCTION

  2. Combining Facebook and Open Learner Models to Encourage Collaborative Learning

    E-Print Network [OSTI]

    Bull, Susan

    Combining Facebook and Open Learner Models to Encourage Collaborative Learning Mohammad Alotaibi of a social network application (Facebook) with individual open learner models at university level, to support collaborative learning. Results suggest that Facebook and open learner models can be used together to support

  3. Power Control for Turbo Coded Symmetrical Collaborative Networks

    E-Print Network [OSTI]

    Cambridge, University of

    Power Control for Turbo Coded Symmetrical Collaborative Networks Weisi Guo1, Ioannis Chatzigeorgiou, we explore the performance of adaptive power control for decode-and-forward (DF) col- laborative. We conclude that power control can greatly benefit a DF collaborative network in a block fading

  4. Software Engineering Students' Cross-site Collaboration: An Experience Report

    E-Print Network [OSTI]

    Newcastle upon Tyne, University of

    Software Engineering Students' Cross-site Collaboration: An Experience Report Sarah Drummond Dept their site's Software Engineering (SE) modules and provided strategic coupling of cross-site student groups and hence their employability. Keywords Software Engineering, Cross-site collaboration, Video conferencing 1

  5. Collaborative Ontological Engineering of Instructional Design Knowledge for an ITS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Collaborative Ontological Engineering of Instructional Design Knowledge for an ITS Authoring could rely on content-based engineering of instructional design (ID) knowledge, i.e. based on principles. Collaborative Ontological Engineering of Instructional Design Knowledge: Challenges of such an Enterprise

  6. TR-IIS-06-011 The Web and Collaborative

    E-Print Network [OSTI]

    Chuang, Tyng-Ruey

    on systematic analysis in exploring dimensions of relation and potential development between geospatial dataTR-IIS-06-011 The Web and Collaborative Geospatial Mapping: A Position Paper Chin-Lung Chang, Yi;1 The Web and Collaborative Geospatial Mapping* -- A Position Paper -- Chin-Lung Chang evirt

  7. Heng Ji & Ralph Grishman Collaborative Entity Extraction and Translation 1

    E-Print Network [OSTI]

    CONTENTS Heng Ji & Ralph Grishman Collaborative Entity Extraction and Translation 1 Index of Subjects and Terms 13 #12;vi CONTENTS #12;Collaborative Entity Extraction and Translation Heng Ji & Ralph s in language S from the #12;2 HENG JI & RALPH GRISHMAN properties of the sequence of tokens t with which

  8. Energy-Optimal Collaborative GPS Localization with Short Range Communication

    E-Print Network [OSTI]

    Cai, Ying

    accuracy. In this paper, we show that the collaboration among proxy devices is helpful to energy-efficiently campuses. Next, we contemplate what is the best method for selfish mobile users to collaborate for energy-efficient localization, and suggest an energy-efficient and/or user fairness localization framework. Next, we develop

  9. Ensuring Safety in Human Robot Collaboration in Assembly

    E-Print Network [OSTI]

    Gupta, Satyandra K.

    -time behavior observed during experiments with a 5 DOF robot and a human safely performing shared assembly tasksEnsuring Safety in Human Robot Collaboration in Assembly Applications Satyandra K. Gupta, Krishnanand Kaipa, Carlos Morato, and Boxuan Zhao #12;Human Robot Collaboration · Robots welding, bolting

  10. China-US Collaborative Research on Life in Terrestrial

    E-Print Network [OSTI]

    Ahmad, Sajjad

    Symposium: China-US Collaborative Research on Life in Terrestrial Geothermal Springs Information, Agenda, and Abstracts June 26-28, 2013, Kunming, China #12;Symposium: China-US Collaborative Research on Life in Terrestrial Geothermal Springs Kunming, China June 26-28, 2013 Information, Agenda

  11. A dislocation-based, strain–gradient–plasticity strengthening model for deformation processed metal–metal composites

    SciTech Connect (OSTI)

    Tian, Liang [Ames Laboratory; Russell, Alan [Ames Laboratory; Anderson, Iver [Ames Laboratory

    2014-01-03T23:59:59.000Z

    Deformation processed metal–metal composites (DMMCs) are high-strength, high-electrical conductivity composites developed by severe plastic deformation of two ductile metal phases. The extraordinarily high strength of DMMCs is underestimated using the rule of mixture (or volumetric weighted average) of conventionally work-hardened metals. In this article, a dislocation-density-based, strain–gradient–plasticity model is proposed to relate the strain-gradient effect with the geometrically necessary dislocations emanating from the interface to better predict the strength of DMMCs. The model prediction was compared with the experimental findings of Cu–Nb, Cu–Ta, and Al–Ti DMMC systems to verify the applicability of the new model. The results show that this model predicts the strength of DMMCs better than the rule-of-mixture model. The strain-gradient effect, responsible for the exceptionally high strength of heavily cold worked DMMCs, is dominant at large deformation strain since its characteristic microstructure length is comparable with the intrinsic material length.

  12. Collaborative Planning for Collaborative Learning: Designing and Promoting New Learning Spaces on Campus

    E-Print Network [OSTI]

    Walter, Scott

    2005-10-07T23:59:59.000Z

    ;? Opportunities for group processing #0;? Intentional design Source: Barkley, E. F., Cross, K. P., & Major, C. H. (2005). Collaborative learning techniques: A handbook for college faculty. San Francisco: Jossey-Bass. Establishing the Baseline #0;? Inquiry... access to information #0;? Support Structure #0;? One-stop Building the Prototype - Overview #0;? Main Lab (?standard? lab configuration with 50 Dell Optiplex GX260s) #0;? Media Lab (13 Macintosh G5s equipped to support desktop publishing, multimedia...

  13. Gearbox Reliability Collaborative Phase 3 Gearbox 2 Test Plan

    SciTech Connect (OSTI)

    Link, H.; Keller, J.; Guo, Y.; McNiff, B.

    2013-04-01T23:59:59.000Z

    Gearboxes in wind turbines have not been achieving their expected design life even though they commonly meet or exceed the design criteria specified in current design standards. One of the basic premises of the National Renewable Energy Laboratory (NREL) Gearbox Reliability Collaborative (GRC) is that the low gearbox reliability results from the absence of critical elements in the design process or insufficient design tools. Key goals of the GRC are to improve design approaches and analysis tools and to recommend practices and test methods resulting in improved design standards for wind turbine gearboxes that lower the cost of energy (COE) through improved reliability. The GRC uses a combined gearbox testing, modeling and analysis approach, along with a database of information from gearbox failures collected from overhauls and investigation of gearbox condition monitoring techniques to improve wind turbine operations and maintenance practices. Testing of Gearbox 2 (GB2) using the two-speed turbine controller that has been used in prior testing. This test series will investigate non-torque loads, high-speed shaft misalignment, and reproduction of field conditions in the dynamometer. This test series will also include vibration testing using an eddy-current brake on the gearbox's high speed shaft.

  14. US/RUSSIAN COLLABORATION; EXPERIMENTS WITH EXPLOSIVE PULSED POWER

    SciTech Connect (OSTI)

    J. GOFORTH; I. LINDEMUTH; ET AL

    2001-04-01T23:59:59.000Z

    Through conferences and technical publications, personnel at Los Alamos National Laboratory (LANL) and the All-Russian Institute of Experimental Physics (VNIIEF) learned of each other's interests in both high explosive pulsed power (HEPP) systems and their applications to fusion and high magnetic field research. The principle forum for contact was the Megagauss (MG) Conference series, becoming visible in 1979 at the MG-II Conference in Washington DC and culminating in Novosibirsk at MG-V in 1989. Conversations at MG-V led to a proposal, advanced by VNIIEF in 1991, to form a collaborative research agreement. After further preliminary conversations, a contingent from VNIIEF arrived at the MG-VI conference in Albuquerque in 1992 with plans to visit Los Alamos after the conference and finalize an agreement. The two laboratories signed a Memorandum of Understanding (MOU) at this time, November of 1992, agreeing to conduct joint experiments using at least two HEPP systems developed by VNIIEF. Since that time, joint experiments have been conducted both at LANL and VNIIEF facilities using a variety of HEPP systems. On a few occasions, the effort has focused on the HEPP system itself, but more often it has focused on scientific applications of mutual interest.

  15. Generating spatially and temporally controllable long-range concentration gradients in a microfluidic device

    E-Print Network [OSTI]

    Vidula, Mahesh K.

    Concentration gradients have important applications in chemical and biological studies. Here we have achieved rapid generation of spatially and temporally controllable concentration gradients of diffusible molecules (i.e. ...

  16. PATTERNS OF LEAF WETTABILITY ALONG AN EXTREME MOISTURE GRADIENT IN WESTERN PATAGONIA, ARGENTINA

    E-Print Network [OSTI]

    Brewer, Carol

    PATTERNS OF LEAF WETTABILITY ALONG AN EXTREME MOISTURE GRADIENT IN WESTERN PATAGONIA, ARGENTINA Patagonia, Argentina. Morphological and structural characteristics of leaves significantly affected leaf surfaces. Keywords: leaf wetness, morphology, water droplet, Patagonia, gradient. Introduction A large

  17. INDUSTRIAL AND SYSTEMS ENGINEERING SEMINAR Semi-Stochastic Gradient Descent Methods

    E-Print Network [OSTI]

    Edinburgh, University of

    () of smooth convex loss functions. We propose a new method, S2GD (Semi-StochasticGradient Descent), which runs equivalent to the computation of a single gradient of the loss, is (log(1 / )). This is achieved by running

  18. Gradient Plasticity Model and its Implementation into MARMOT

    SciTech Connect (OSTI)

    Barker, Erin I.; Li, Dongsheng; Zbib, Hussein M.; Sun, Xin

    2013-08-01T23:59:59.000Z

    The influence of strain gradient on deformation behavior of nuclear structural materials, such as boby centered cubic (bcc) iron alloys has been investigated. We have developed and implemented a dislocation based strain gradient crystal plasticity material model. A mesoscale crystal plasticity model for inelastic deformation of metallic material, bcc steel, has been developed and implemented numerically. Continuum Dislocation Dynamics (CDD) with a novel constitutive law based on dislocation density evolution mechanisms was developed to investigate the deformation behaviors of single crystals, as well as polycrystalline materials by coupling CDD and crystal plasticity (CP). The dislocation density evolution law in this model is mechanism-based, with parameters measured from experiments or simulated with lower-length scale models, not an empirical law with parameters back-fitted from the flow curves.

  19. A Framework like a tool for specify motivating Collaborative Learning Participatory Simulations

    E-Print Network [OSTI]

    Antunes, Pedro

    1 A Framework like a tool for specify motivating Collaborative Learning Participatory Simulations that collaborative participatory simulations improve teaching and learning, increasing motivation inside. Keywords: Handhelds. Gestures, Sketches. Collaborative Learning. Participatory Simulation. 1. Introduction

  20. Learn more at: http://www.washington.edu/2y2d/fostering-collaboration/ November 2011 response to the question "What will collaborative research and education look like in the 21

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    Learn more at: http://www.washington.edu/2y2d/fostering-collaboration/ A November 2011 response. ...is incubated in grassroots initiatives Faculty will increasingly desire and demand opportunities of excellence, central to the recruitment and retention of high-quality faculty and students, allowing teams

  1. Shading curves: vector-based drawing with explicit gradient control

    E-Print Network [OSTI]

    Lieng, Henrik; Tasse, Flora; Kosinka, Ji?í; Dodgson, Neil A.

    2015-01-01T23:59:59.000Z

    gradient. We resolve this problem by using subdivision surfaces that are constructed from shading curves and their shading profiles. Categories and Subject Descriptors (according to ACM CCS): I.3.3 [Computer Graphics]: Picture/Image Gene- ration... potential sources of visual artefacts in Illustrator’s tool: the rendering procedure, the deformation procedure, and blending with underlying layers. Figure 18 shows images coloured with Illustrator’s tool, where arte- facts are visible. In comparison, our...

  2. Determination of dispersivities from a natural-gradient dispersion test

    E-Print Network [OSTI]

    Hoover, Caroline Marie

    1985-01-01T23:59:59.000Z

    of H drolo can be valuable predictive tool s (Wang and Anderson, 1982). Since the late 1800's, mathematical models have been used in problems of groundwater flow. Their appl ication now extends to problems of contaminant transport and migration...DETERMINATION OF DISPERSIVITIES FROM A NATURAL-GRADIENT DISPERSION TEST A Thesis by CAROLINE MARIE HOOVER Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER...

  3. Solar rotation rate and its gradients during cycle 23

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu; S. M. Chitre

    2008-05-22T23:59:59.000Z

    Available helioseismic data now span almost the entire solar activity cycle 23 making it possible to study solar-cycle related changes of the solar rotation rate in detail. In this paper we study how the solar rotation rate, in particular, the zonal flows change with time. In addition to the zonal flows that show a well known pattern in the solar convection zone, we also study changes in the radial and latitudinal gradients of the rotation rate, particularly in the shear layer that is present in the immediate sub-surface layers of the Sun. In the case of the zonal-flow pattern, we find that the band indicating fast rotating region close to the equator seems to have bifurcated around 2005. Our investigation of the rotation-rate gradients show that the relative variation in the rotation-rate gradients is about 20% or more of their average values, which is much larger than the relative variation in the rotation rate itself. These results can be used to test predictions of various solar dynamo models.

  4. Magnetic field gradients in solar wind plasma and geophysics periods

    E-Print Network [OSTI]

    A. Bershadskii

    2006-11-16T23:59:59.000Z

    Using recent data obtained by Advanced Composition Explorer (ACE) the pumping scale of the magnetic field gradients of the solar wind plasma has been calculated. This pumping scale is found to be equal to 24h $\\pm$ 2h. The ACE spacecraft orbits at the L1 libration point which is a point of Earth-Sun gravitational equilibrium about 1.5 million km from Earth. Since the Earth's magnetosphere extends into the vacuum of space from approximately 80 to 60,000 kilometers on the side toward the Sun the pumping scale cannot be a consequence of the 24h-period of the Earth's rotation. Vise versa, a speculation is suggested that for the very long time of the coexistence of Earth and of the solar wind the weak interaction between the solar wind and Earth could lead to stochastic synchronization between the Earth's rotation and the pumping scale of the solar wind magnetic field gradients. This synchronization could transform an original period of the Earth's rotation to the period close to the pumping scale of the solar wind magnetic field gradients.

  5. CONTINUOUS EDGE GRADIENT-BASED TEMPLATE MATCHING FOR ARTICULATED OBJECTS

    E-Print Network [OSTI]

    Daniel Mohr; Gabriel Zachmann

    template matching, deformable object detection, confidence map, edge feature, graphics hardware In this paper, we propose a novel edge gradient based template matching method for object detection. In contrast to other methods, ours does not perform any binarization or discretization during the online matching. This is facilitated by a new continuous edge gradient similarity measure. Its main components are a novel edge gradient operator, which is applied to query and template images, and the formulation as a convolution, which can be computed very efficiently in Fourier space. We compared our method to a state-of-the-art chamfer based matching method. The results demonstrate that our method is much more robust against weak edge response and yields much better confidence maps with fewer maxima that are also more significant. In addition, our method lends itself well to efficient implementation on GPUs: at a query image resolution of 320 × 256 and a template resolution of 80 × 80 we can generate about 330 confidence maps per second. 1

  6. Geothermal gradient map of the conterminous United States. Second edition

    SciTech Connect (OSTI)

    Kron, A.; Stix, J.

    1982-01-01T23:59:59.000Z

    The second edition of the Geothermal Gradient Map of the Conterminous United States (Kron and Stix 1982) is described and the changes made since the first edition (Kron and Heiken 1980) are compared. The second edition of the map presents a compilation of over 1700 wells that have been measured for temperature belwo 50 m and whose temperature/depth profiles are linear, or composed of linear segments which reflect changes in the thermal conductivity of the rocks rather than hydrology. The data are displayed at an enlarged scale of 1:2,500,000 and in a new format which shows the location, depth, and gradient of each well in a single color-coded symbol. This edition contains over two times the amount of data shown on the first map and is accompained by a table, listing for each well its location, depth, gradient, heat flow (where available), thermal conductivity (where available), and a reference. Over 200 references have been consulted and are presented with the data.

  7. Multiscale Analysis of the Gradient of Linear Polarisation

    E-Print Network [OSTI]

    Robitaille, J -F

    2015-01-01T23:59:59.000Z

    We propose a new multiscale method to calculate the amplitude of the gradient of the linear polarisation vector using a wavelet-based formalism. We demonstrate this method using a field of the Canadian Galactic Plane Survey (CGPS) and show that the filamentary structure typically seen in gradients of linear polarisation maps depends strongly on the instrumental resolution. Our analysis reveals that different networks of filaments are present on different angular scales. The wavelet formalism allows us to calculate the power spectrum of the fluctuations seen in gradients of linear polarisation maps and to determine the scaling behaviour of this quantity. The power spectrum is found to follow a power law with gamma ~ 2.1. We identify a small drop in power between scales of 80 well to the overlap in the u-v plane between the Effelsberg 100-m telescope and the DRAO 26-m telescope data. We suggest that this drop is due to undersampling present in the 26-m telescope data. I...

  8. Eddy currents in a gradient coil, modelled as circular loops of strips

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    Eddy currents in a gradient coil, modelled as circular loops of strips J.M.B. Kroot, S.J.L. van. Due to induction eddy currents occur which lead to the so-called edge-effect. The edge- effect depends the gradient coils themselves. Eddy currents occur, causing perturbations on the expected gradient field

  9. Experimental and theoretical studies of oxygen gradients in rat pial microvessels

    E-Print Network [OSTI]

    Popel, Aleksander S.

    no substantial impact on the transmural PO2 gradient. Journal of Cerebral Blood Flow & Metabolism (2008) 28, 1597Experimental and theoretical studies of oxygen gradients in rat pial microvessels Maithili Sharan1 near cortical arterioles and transmural PO2 gradients in the pial arterioles of the rat. Under control

  10. RAL-TR-2002-034 A Stopping Criterion for the Conjugate Gradient Algorithm in

    E-Print Network [OSTI]

    Mihajlovic, Milan D.

    Method Framework Mario Arioli 1 ABSTRACT The Conjugate Gradient method has always been successfully used for the conjugate gradient method 5 4 Numerical experiments 10 4.1 L-shape test problems stopping criterion for the conjugate gradient algorithm. The #12;nite element method approximates the weak

  11. Ilya Lashuk and Andrew Knyazev 1 Steepest descent and conjugate gradient methods

    E-Print Network [OSTI]

    Knyazev, Andrew

    Ilya Lashuk and Andrew Knyazev 1 Steepest descent and conjugate gradient methods with variable Mountain Conference 2006 Steepest descent and conjugate gradient methods with variable preconditioning #12 Steepest descent and conjugate gradient methods with variable preconditioning #12;Ilya Lashuk and Andrew

  12. Inverse estimation of surface heating condition in a three-dimensional object using conjugate gradient method

    E-Print Network [OSTI]

    Zhang, Yuwen

    heat conduction Laser Gaussian profile Conjugate gradient method a b s t r a c t Temperature and heat gradient method Jianhua Zhou, Yuwen Zhang *, J.K. Chen, Z.C. Feng Department of Mechanical and Aerospace gradient method (CGM) with temperature and heat flux measured on back surface (opposite to the heated

  13. A Set of Conjugate Gradient Routines for Real and Complex Arithmetics

    E-Print Network [OSTI]

    The Conjugate Gradient method was proposed in different versions in the early 50s in separate contributionsA Set of Conjugate Gradient Routines for Real and Complex Arithmetics Val´erie Frayss´e Luc Giraud of the preconditioned conjugate gradient (CG) algorithm for both real and complex, single and double precision

  14. Preconditioned conjugate gradient method for the sparse generalized eigenvalue problem in electronic structure

    E-Print Network [OSTI]

    Haynes, Peter

    Preconditioned conjugate gradient method for the sparse generalized eigenvalue problem based on the conjugate gradient method is presented. The method is applied to first­principles elec problem, cast into variational form, is solved by the conjugate gradient method without first transforming

  15. Performance and Scalability of Preconditioned Conjugate Gradient Methods on Parallel Computers \\Lambda

    E-Print Network [OSTI]

    Kumar, Vipin

    Performance and Scalability of Preconditioned Conjugate Gradient Methods on Parallel Computers­scale parallel computers, iterative methods such as the Conjugate Gradient method for solving such systems of an iteration of the Preconditioned Conjugate Gradient Algorithm on parallel architectures with a variety

  16. A Set of Conjugate Gradient Routines for Real and Complex Arithmetics

    E-Print Network [OSTI]

    systems, Krylov methods, CG, reverse communication, distributed mem­ ory. 1 The Conjugate Gradient algorithm 1.1 General description The Conjugate Gradient method was proposed in di#erent versions with the symmetric Lanczos matrix There is a close relationship between the conjugate gradient method and the Lanczos

  17. Solving a Two-Dimensional Elliptic Model Problem with the Conjugate Gradient Method Using

    E-Print Network [OSTI]

    Gobbert, Matthias K.

    Solving a Two-Dimensional Elliptic Model Problem with the Conjugate Gradient Method Using Matrix Preconditioned Conjugate Gradient method in Matlab can be optimized in terms of wall clock time and, more-free Preconditioned Conjugate Gradient method. This superior algorithm computes the same numerical solution to our

  18. Conjugate gradient method for dual-dual mixed formulations Gabriel N. Gatica y Norbert Heuer z

    E-Print Network [OSTI]

    Heuer, Norbert

    Conjugate gradient method for dual-dual mixed formulations #3; Gabriel N. Gatica y Norbert Heuer z, the conjugate gradient method with this special inner product can be used as iterative solver. For a model-dual variational formulation, conjugate gradient method. Mathematics subject classi#12;cations (1991). 65N30, 65N22

  19. Convergence of Three-term Conjugate Gradient Methods Y. H. Dai and Y. Yuan

    E-Print Network [OSTI]

    Yuan, Ya-xiang

    Convergence of Three-term Conjugate Gradient Methods Y. H. Dai and Y. Yuan State Key Laboratory@lsec.cc.ac.cn, yyx@lsec.cc.ac.cn Abstract This paper studies the three-term conjugate gradient method for unconstrained opti- mization. The method includes the classical (two-term) conjugate gradient method

  20. Time Complexity of a Parallel Conjugate Gradient Solver for Light Scattering Simulations

    E-Print Network [OSTI]

    Hoffmann, Walter

    parallelization for distributed memory computers of a preconditioned Conjugate Gradient method, applied to solve of the Conjugate Gradient method is analyzed theoretically. First expressions for the execution time for three, preconditioned conjugate gradient method, data decomposition, time complexity analysis, performance measurement

  1. A fast GPU Implementation of the Deflated Preconditioned Conjugate Gradient method

    E-Print Network [OSTI]

    Boyer, Edmond

    A fast GPU Implementation of the Deflated Preconditioned Conjugate Gradient method List of authors to the fastest method: DIPCG2. · (CGVV) Conjugate Gradient - Vanilla Version, · (CGBIC) Conjugate Gradient Preconditioned Conjugate Gra- dient Method. Most of the important building blocks of this algorithm could

  2. The Role of the Inner Product in Stopping Criteria for Conjugate Gradient Iterations

    E-Print Network [OSTI]

    Holst, Michael J.

    stopping criteria are derived for conjugate gradient (CG) methods, based on iteration parameters criteria, conjugate gradient methods, B-normal matrices 1 Introduction Unlike a direct method, an iterative1 The Role of the Inner Product in Stopping Criteria for Conjugate Gradient Iterations S. F. Ashby

  3. Implementation of a parallel conjugate gradient method for simulation of elastic light scattering

    E-Print Network [OSTI]

    1 Implementation of a parallel conjugate gradient method for simulation of elastic light scattering solved with (preconditioned) conjugate gradient methods. For realistic problems the size of the matrix gradient method for this type of problems, with emphasis on coarse grain distributed memory implementations

  4. Copyright information to be inserted by the Publishers ANALYSIS ON THE CONJUGATE GRADIENT

    E-Print Network [OSTI]

    Yuan, Ya-xiang

    Copyright information to be inserted by the Publishers ANALYSIS ON THE CONJUGATE GRADIENT METHOD YA 17 January 1993) In this paper we analyze the conjugate gradient method when the objective function is quadratic. We apply backward analyses to study the quadratic termination of the conjugate gradient method

  5. Exploiting hyper-sparsity when computing preconditioners for conjugate gradients in interior point methods

    E-Print Network [OSTI]

    Hall, Julian

    for conjugate gradients in interior point methods 1 #12;Hyper-sparsity in operations with B-1 Represent B-1 computing preconditioners for conjugate gradients in interior point methods 3 #12;Interior point methods computing preconditioners for conjugate gradients in interior point methods 4 #12;Design

  6. Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method

    E-Print Network [OSTI]

    Nocedal, Jorge

    Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method Jos subroutines for automatically generating pre­ conditioners for the conjugate gradient method. It is designed the conjugate gradient method. They are designed for solving a sequence of linear systems, A i x = b i ; i = 1

  7. A conjugate-gradient based approach for approximate solutions of quadratic programs

    E-Print Network [OSTI]

    Forsgren, Anders

    on the two-norm of the columns, the method is equivalent to the conjugate-gradient method. Further, the above, the numerical results demonstrate that, like the conjugate-gradient method, a rapid decrease of the objective. column generation, conjugate-gradient method, intensity-modulated radiation therapy, step

  8. 3D Shape from Silhouette Points in Registered 2D Images Using Conjugate Gradient Method

    E-Print Network [OSTI]

    Hoff, William A.

    3D Shape from Silhouette Points in Registered 2D Images Using Conjugate Gradient Method Andrzej version of the conjugate gradient method. We take advantage of the structure of the problem to make polynomial function. The approximate problem is solved using a nonlinear conjugate gradient solver that takes

  9. Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method

    E-Print Network [OSTI]

    Nocedal, Jorge

    Algorithm PREQN: Fortran 77 Subroutines for Preconditioning the Conjugate Gradient Method Jose Luis for automatically generating pre- conditioners for the conjugate gradient method. It is designed for solving: Preconditioning, conjugate gradient method, quasi- Newton method, Hessian-free Newton method, limited memory

  10. PRECONDITIONED CONJUGATE GRADIENT METHODS FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS

    E-Print Network [OSTI]

    Waterloo, University of

    PRECONDITIONED CONJUGATE GRADIENT METHODS FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS P. CHIN of using a conjugate gradient type method with an incomplete LU factorization preconditioner for two is to use an iterative matrix method. Recently, several authors have applied conjugate gradient type methods

  11. Parallelizable Preconditioned Conjugate Gradient Methods for the Cray Y-MP and the TMC CM-2

    E-Print Network [OSTI]

    Navon, Michael

    Parallelizable Preconditioned Conjugate Gradient Methods for the Cray Y-MP and the TMC CM-2 William preconditioned conjugate gradient methods to the numerical solution of the diffusion equation governing the flow provides a comparison of the performance characteristics of several preconditioned conjugate gradient (PCG

  12. A MULTI-PRECONDITIONED CONJUGATE GRADIENT ROBERT BRIDSON AND CHEN GREIF

    E-Print Network [OSTI]

    Bridson, Robert

    propose a generalization of the conjugate gradient method that uses multiple preconditioners, combining and differences with the standard and block conjugate gradient methods. Numerical examples illustrate and validate, preconditioning, Krylov subspace solvers 1. Introduction. The conjugate gradient (CG) method is celebrating its 53

  13. A SURVEY OF NONLINEAR CONJUGATE GRADIENT METHODS WILLIAM W. HAGER AND HONGCHAO ZHANG

    E-Print Network [OSTI]

    Zhang, Hongchao

    A SURVEY OF NONLINEAR CONJUGATE GRADIENT METHODS WILLIAM W. HAGER AND HONGCHAO ZHANG Abstract. This paper reviews the development of different versions of nonlinear conjugate gradient methods, with special attention given to global convergence properties. Key words. Nonlinear conjugate gradient methods

  14. ON THE BEHAVIOR OF THE CONJUGATE-GRADIENT METHOD ON ILL-CONDITIONED PROBLEMS

    E-Print Network [OSTI]

    Forsgren, Anders

    ON THE BEHAVIOR OF THE CONJUGATE-GRADIENT METHOD ON ILL-CONDITIONED PROBLEMS Anders FORSGREN Abstract We study the behavior of the conjugate-gradient method for solving a set of linear equations. conjugate-gradient method, symmetric positive-definite ma- trix, ill-conditioning AMS subject

  15. On the Relation Between Steep Monoclinal Flexure Zones and Steep Hydraulic Gradients

    E-Print Network [OSTI]

    Lyakhovsky, Vladimir

    On the Relation Between Steep Monoclinal Flexure Zones and Steep Hydraulic Gradients by Y. Yechieli1, U. Kafri2, S. Wollman2, V. Lyakhovsky2, and R. Weinberger2 Abstract Steep hydraulic gradients of the hydraulic conductivity, which is responsible for the steep gradients, has seldom been studied. We present

  16. WORLD RECORD ACCELERATING GRADIENT ACHIEVED IN A SUPERCONDUCTING NIOBIUM RF CAVITY

    E-Print Network [OSTI]

    Geng, Rong-Li

    WORLD RECORD ACCELERATING GRADIENT ACHIEVED IN A SUPERCONDUCTING NIOBIUM RF CAVITY R.L. Geng On November 16, 2004, a CW accelerating gradient of 46 MV/m was achieved in a superconducting niobium cav- ity/m was achieved. This represents a world record gradient in a niobium RF resonator. At a reduced temperature of 1

  17. Following the development of a virtual prototype study at the Virtual Engineering Centre (VEC), the collaborative expertise and

    E-Print Network [OSTI]

    Zharkova, Valentina V.

    with us The Hartree Centre is an industrial gateway to world-class high performance computing (HPC), the collaborative expertise and access to the Science and Technology Facilities Council's (STFC) Hartree Centre) and simulation technology. A research collaboratory in association with IBM and underpinned by more than £37.5m

  18. Thinking Tools for Successful Collaborative Initiatives - 13351

    SciTech Connect (OSTI)

    Boucher, Laurel A. [The Laurel Co., P.O. Box 218, Wetmore, MI (United States)] [The Laurel Co., P.O. Box 218, Wetmore, MI (United States)

    2013-07-01T23:59:59.000Z

    Successful collaboration requires effective communication and collective problem solving. Regardless of the subject area --- environmental remediation, waste management, program planning and budgeting --- those involved must focus their efforts in an orderly and cooperative manner. A thinking tool is a technique used to get individuals to focus on specific components of the task at the same time and to eliminate the 'noise' that accompanies communications among individuals with different objectives and different styles of communicating. For example, one of these thinking tools is a technique which enables a working group to delineate its roles, responsibilities and communication protocols so that it can deliver the right information to the right people at the right time. Another enables a group to objectively and collectively evaluate and improve a policy, plan, or program. A third technique enables a group to clarify its purpose and direction while generating interest and buy-in. A fourth technique makes it possible for a group with polarized opinions to acknowledge their differences as well as what they have in common. A fifth technique enables a group to consider a subject of importance from all perspectives so as to produce a more comprehensive and sustainable solution. These thinking tools make effective communication and collective problem solving possible in radioactive waste management and remediation. They can be used by a wide spectrum of professionals including policy specialists, program administrators, program and project managers, and technical specialists. (author)

  19. Unexpected Collaborations: Kids' Appropriation of GarageBand as a Group Creative Tool

    E-Print Network [OSTI]

    Antin, Judd; Perkel, Dan; Sims, Christo

    2008-01-01T23:59:59.000Z

    collaboration. and digital media classes for both kids andin two semesters of a digital media production class. DuringKeywords Kids, Digital Media, Collaboration, Creativity,

  20. Thermal gradient-induced forces on geodetic reference masses for LISA

    E-Print Network [OSTI]

    L. Carbone; A. Cavalleri; G. Ciani; R. Dolesi; M. Hueller; D. Tombolato; S. Vitale; W. J. Weber

    2007-06-29T23:59:59.000Z

    The low frequency sensitivity of space-borne gravitational wave observatories will depend critically on the geodetic purity of the trajectories of orbiting test masses. Fluctuations in the temperature difference across the enclosure surrounding the free-falling test mass can produce noisy forces through several processes, including the radiometric effect, radiation pressure, and outgassing. We present here a detailed experimental investigation of thermal gradient-induced forces for the LISA gravitational wave mission and the LISA Pathfinder, employing high resolution torsion pendulum measurements of the torque on a LISA-like test mass suspended inside a prototype of the LISA gravitational reference sensor that will surround the test mass in orbit. The measurement campaign, accompanied by numerical simulations of the radiometric and radiation pressure effects, allows a more accurate and representative characterization of thermal-gradient forces in the specific geometry and environment relevant to LISA free-fall. The pressure dependence of the measured torques allows clear identification of the radiometric effect, in quantitative agreement with the model developed. In the limit of zero gas pressure, the measurements are most likely dominated by outgassing, but at a low level that does not threaten the LISA sensitivity goals.