National Library of Energy BETA

Sample records for reverse fault rectangles

  1. Preliminary observations on Quaternary reverse faulting along the southern front of the Northern Range of Trinidad

    SciTech Connect (OSTI)

    Beltran, C. , Caracus )

    1993-02-01

    Several geomorphological evidences of Quaternary reverse faulting are observed along the southern front of the Northern Range in Trinidad between Port-of-Spain and Matura Point. Such a mountain front is associated to a reverse fault system showing an imbricated pattern southward. In the north, the system is limited by a structural feature showing an important vertical component. Southward this system progressively changes to low angle faults. This geometry is corroborated by seismic profiling in the continent shelf. The active faulting evidences consist in lateral drainage offsets, fault trenches, sag-ponds, triangular facets, and saddles. Some quaternary terraces show fault scarps and tilting. We postulate that these reverse fault systems as Arima Fault instead of El Pilar fault as it is not actually connected to the San Sebestian-El Pilar right-lateral slip system, due to the southward prolongation of the southern limit of the Caribbean Plate through the fault system of Los Bajos-El Soldado.

  2. Imaging Faults with Reverse-Time Migration for Geothermal Exploration at Jemez Pueblo in New Mexico

    SciTech Connect (OSTI)

    Huang, Lianjie; Albrecht, Michael; Kaufman, Greg; Kelley, Shari; Rehfeldt, Kenneth; Zhang, Zhifu

    2011-01-01

    The fault zones at Jemez Pueblo may dominate the flow paths of hot water, or confine the boundaries of the geothermal reservoir. Therefore, it is crucial to image the geometry of these fault zones for geothermal exploration in the area. We use reverse-time migration with a separation imaging condition to image the faults at Jemez Pueblo. A finite-difference full-wave equation method with a perfectly-matching-layer absorbing boundary condition is used for backward propagation of seismic reflection data from receivers and forward propagation of wavefields from sources. In the imaging region, the wavefields are separated into the upgoing and downgoing waves, and leftgoing and rightgoing waves. The upgoing and downgoing waves are used to obtain the downward-looking image, and the leftgoing and rightgoing waves are used to form the left-looking image and right-looking image from sources. The left-looking and right-looking images are normally weaker than the downward-looking image because the reflections from the fault zones are much weaker than those from sedimentary layers, but these migration results contain the images of the faults. We apply our reverse-time migration with a wavefield separation imaging condition to seismic data acquired at Jemez Pueblo, and our preliminary results reveal many faults in the area.

  3. Hawaii Faults

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

    Nicole Lautze

    2015-01-01

    Faults combined from USGS 2007 Geologic Map of the State of Hawaii and the USGS Quaternary Fault and Fold database. This data is in shapefile format.

  4. Fault finder

    DOE Patents [OSTI]

    Bunch, Richard H.

    1986-01-01

    A fault finder for locating faults along a high voltage electrical transmission line. Real time monitoring of background noise and improved filtering of input signals is used to identify the occurrence of a fault. A fault is detected at both a master and remote unit spaced along the line. A master clock synchronizes operation of a similar clock at the remote unit. Both units include modulator and demodulator circuits for transmission of clock signals and data. All data is received at the master unit for processing to determine an accurate fault distance calculation.

  5. Photovoltaic System Fault Detection

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

    Photovoltaic System Fault Detection and Diagnostics using Laterally Primed Adaptive Resonance Theory Neural Network C. Birk Jones, Joshua S. Stein, Sigifredo Gonzalez, and Bruce H. King Sandia National Laboratories, Albuquerque, NM, 87185, U.S.A Abstract-Cost effective integration of solar photovoltaic (PV) systems requires increased reliability. This can be achieved with a robust fault detection and diagnostic (FDD) tool that auto- matically discovers faults. This paper introduces the Laterally

  6. Fault Current Limiters

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

    Other benefits include: &17; Enhanced system safety, stability, and efficiency of the power ... large fault current desaturates the iron core of the series AC coils and the increased ...

  7. Solar system fault detection

    DOE Patents [OSTI]

    Farrington, Robert B.; Pruett, Jr., James C.

    1986-01-01

    A fault detecting apparatus and method are provided for use with an active solar system. The apparatus provides an indication as to whether one or more predetermined faults have occurred in the solar system. The apparatus includes a plurality of sensors, each sensor being used in determining whether a predetermined condition is present. The outputs of the sensors are combined in a pre-established manner in accordance with the kind of predetermined faults to be detected. Indicators communicate with the outputs generated by combining the sensor outputs to give the user of the solar system and the apparatus an indication as to whether a predetermined fault has occurred. Upon detection and indication of any predetermined fault, the user can take appropriate corrective action so that the overall reliability and efficiency of the active solar system are increased.

  8. Solar system fault detection

    DOE Patents [OSTI]

    Farrington, R.B.; Pruett, J.C. Jr.

    1984-05-14

    A fault detecting apparatus and method are provided for use with an active solar system. The apparatus provides an indication as to whether one or more predetermined faults have occurred in the solar system. The apparatus includes a plurality of sensors, each sensor being used in determining whether a predetermined condition is present. The outputs of the sensors are combined in a pre-established manner in accordance with the kind of predetermined faults to be detected. Indicators communicate with the outputs generated by combining the sensor outputs to give the user of the solar system and the apparatus an indication as to whether a predetermined fault has occurred. Upon detection and indication of any predetermined fault, the user can take appropriate corrective action so that the overall reliability and efficiency of the active solar system are increased.

  9. OpenStudio - Fault Modeling

    Energy Science and Technology Software Center (OSTI)

    2014-09-19

    This software record documents the OpenStudio fault model development portion of the Fault Detection and Diagnostics LDRD project.The software provides a suite of OpenStudio measures (scripts) for modeling typical HVAC system faults in commercial buildings and also included supporting materials: example projects and OpenStudio measures for reporting fault costs and energy impacts.

  10. Development of Hydrologic Characterization Technology of Fault Zones

    SciTech Connect (OSTI)

    Karasaki, Kenzi; Onishi, Tiemi; Wu, Yu-Shu

    2008-03-31

    Through an extensive literature survey we find that there is very limited amount of work on fault zone hydrology, particularly in the field using borehole testing. The common elements of a fault include a core, and damage zones. The core usually acts as a barrier to the flow across it, whereas the damage zone controls the flow either parallel to the strike or dip of a fault. In most of cases the damage zone isthe one that is controlling the flow in the fault zone and the surroundings. The permeability of damage zone is in the range of two to three orders of magnitude higher than the protolith. The fault core can have permeability up to seven orders of magnitude lower than the damage zone. The fault types (normal, reverse, and strike-slip) by themselves do not appear to be a clear classifier of the hydrology of fault zones. However, there still remains a possibility that other additional geologic attributes and scaling relationships can be used to predict or bracket the range of hydrologic behavior of fault zones. AMT (Audio frequency Magneto Telluric) and seismic reflection techniques are often used to locate faults. Geochemical signatures and temperature distributions are often used to identify flow domains and/or directions. ALSM (Airborne Laser Swath Mapping) or LIDAR (Light Detection and Ranging) method may prove to be a powerful tool for identifying lineaments in place of the traditional photogrammetry. Nonetheless not much work has been done to characterize the hydrologic properties of faults by directly testing them using pump tests. There are some uncertainties involved in analyzing pressure transients of pump tests: both low permeability and high permeability faults exhibit similar pressure responses. A physically based conceptual and numerical model is presented for simulating fluid and heat flow and solute transport through fractured fault zones using a multiple-continuum medium approach. Data from the Horonobe URL site are analyzed to demonstrate the

  11. Fault tolerant linear actuator

    DOE Patents [OSTI]

    Tesar, Delbert

    2004-09-14

    In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.

  12. Computer hardware fault administration

    DOE Patents [OSTI]

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-09-14

    Computer hardware fault administration carried out in a parallel computer, where the parallel computer includes a plurality of compute nodes. The compute nodes are coupled for data communications by at least two independent data communications networks, where each data communications network includes data communications links connected to the compute nodes. Typical embodiments carry out hardware fault administration by identifying a location of a defective link in the first data communications network of the parallel computer and routing communications data around the defective link through the second data communications network of the parallel computer.

  13. DIFFERENTIAL FAULT SENSING CIRCUIT

    DOE Patents [OSTI]

    Roberts, J.H.

    1961-09-01

    A differential fault sensing circuit is designed for detecting arcing in high-voltage vacuum tubes arranged in parallel. A circuit is provided which senses differences in voltages appearing between corresponding elements likely to fault. Sensitivity of the circuit is adjusted to some level above which arcing will cause detectable differences in voltage. For particular corresponding elements, a group of pulse transformers are connected in parallel with diodes connected across the secondaries thereof so that only voltage excursions are transmitted to a thyratron which is biased to the sensitivity level mentioned.

  14. Row fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2008-10-14

    An apparatus, program product and method checks for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  15. Row fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2012-02-07

    An apparatus, program product and method check for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  16. Row fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-02-23

    An apparatus and program product check for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  17. Dynamic Fault Detection Chassis

    SciTech Connect (OSTI)

    Mize, Jeffery J

    2007-01-01

    Abstract The high frequency switching megawatt-class High Voltage Converter Modulator (HVCM) developed by Los Alamos National Laboratory for the Oak Ridge National Laboratory's Spallation Neutron Source (SNS) is now in operation. One of the major problems with the modulator systems is shoot-thru conditions that can occur in a IGBTs H-bridge topology resulting in large fault currents and device failure in a few microseconds. The Dynamic Fault Detection Chassis (DFDC) is a fault monitoring system; it monitors transformer flux saturation using a window comparator and dV/dt events on the cathode voltage caused by any abnormality such as capacitor breakdown, transformer primary turns shorts, or dielectric breakdown between the transformer primary and secondary. If faults are detected, the DFDC will inhibit the IGBT gate drives and shut the system down, significantly reducing the possibility of a shoot-thru condition or other equipment damaging events. In this paper, we will present system integration considerations, performance characteristics of the DFDC, and discuss its ability to significantly reduce costly down time for the entire facility.

  18. Investigations of stacking fault density in perpendicular recording media

    SciTech Connect (OSTI)

    Piramanayagam, S. N. Varghese, Binni; Yang, Yi; Kiat Lee, Wee; Khume Tan, Hang

    2014-06-28

    In magnetic recording media, the grains or clusters reverse their magnetization over a range of reversal field, resulting in a switching field distribution. In order to achieve high areal densities, it is desirable to understand and minimize such a distribution. Clusters of grains which contain stacking faults (SF) or fcc phase have lower anisotropy, an order lower than those without them. It is believed that such low anisotropy regions reverse their magnetization at a much lower reversal field than the rest of the material with a larger anisotropy. Such clusters/grains cause recording performance deterioration, such as adjacent track erasure and dc noise. Therefore, the observation of clusters that reverse at very low reversal fields (nucleation sites, NS) could give information on the noise and the adjacent track erasure. Potentially, the observed clusters could also provide information on the SF. In this paper, we study the reversal of nucleation sites in granular perpendicular media based on a magnetic force microscope (MFM) methodology and validate the observations with high resolution cross-section transmission electron microscopy (HRTEM) measurements. Samples, wherein a high anisotropy CoPt layer was introduced to control the NS or SF in a systematic way, were evaluated by MFM, TEM, and magnetometry. The magnetic properties indicated that the thickness of the CoPt layer results in an increase of nucleation sites. TEM measurements indicated a correlation between the thickness of CoPt layer and the stacking fault density. A clear correlation was also observed between the MFM results, TEM observations, and the coercivity and nucleation field of the samples, validating the effectiveness of the proposed method in evaluating the nucleation sites which potentially arise from stacking faults.

  19. Automatic Fault Classification

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

    Automatic Fault Classification of Photovoltaic Strings Based on an In Situ IV Characterization System and a Gaussian Process Algorithm. C. Birk Jones ∗ , Manel Mart´ ınez-Ram´ on ‡ , § Ryan Smith † , Craig K. Carmignani ∗ , Olga Lavrova ∗ , Charles Robinson ∗ , and Joshua S. Stein ∗ ∗ Sandia National Laboratories Solar PV & Grid Integration, Albuquerque, NM, USA. ‡ Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, NM, USA, §

  20. Fault Detection Tool Project: Automatic Discovery of Faults using...

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

    Energy Systems LaboratoryBrayton Lab Photovoltaic Systems Evaluation Laboratory PV ... HomeEnergy, Photovoltaic, Renewable Energy, Research & Capabilities, SolarFault ...

  1. Fault Mapping | Open Energy Information

    Open Energy Info (EERE)

    to help locate and identify geothermal systems that rely on faults as high permeability pathways for fluid circulation. There are many techniques that can be done to...

  2. Fault current limiter

    DOE Patents [OSTI]

    Darmann, Francis Anthony

    2013-10-08

    A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

  3. Final Technical Report: PV Fault Detection Tool.

    SciTech Connect (OSTI)

    King, Bruce Hardison; Jones, Christian Birk

    2015-12-01

    The PV Fault Detection Tool project plans to demonstrate that the FDT can (a) detect catastrophic and degradation faults and (b) identify the type of fault. This will be accomplished by collecting fault signatures using different instruments and integrating this information to establish a logical controller for detecting, diagnosing and classifying each fault.

  4. Colorado Regional Faults

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

    Hussein, Khalid

    2012-02-01

    Citation Information: Originator: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Originator: Colorado Geological Survey (CGS) Publication Date: 2012 Title: Regional Faults Edition: First Publication Information: Publication Place: Earth Science & Observation Center, Cooperative Institute for Research in Environmental Science, University of Colorado, Boulder Publisher: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Description: This layer contains the regional faults of Colorado Spatial Domain: Extent: Top: 4543192.100000 m Left: 144385.020000 m Right: 754585.020000 m Bottom: 4094592.100000 m Contact Information: Contact Organization: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Contact Person: Khalid Hussein Address: CIRES, Ekeley Building Earth Science & Observation Center (ESOC) 216 UCB City: Boulder State: CO Postal Code: 80309-0216 Country: USA Contact Telephone: 303-492-6782 Spatial Reference Information: Coordinate System: Universal Transverse Mercator (UTM) WGS’1984 Zone 13N False Easting: 500000.00000000 False Northing: 0.00000000 Central Meridian: -105.00000000 Scale Factor: 0.99960000 Latitude of Origin: 0.00000000 Linear Unit: Meter Datum: World Geodetic System 1984 (WGS ’984) Prime Meridian: Greenwich Angular Unit: Degree Digital Form: Format Name: Shape file

  5. Towards reversible basic linear algebra subprograms: A performance study

    SciTech Connect (OSTI)

    Perumalla, Kalyan S.; Yoginath, Srikanth B.

    2014-12-06

    Problems such as fault tolerance and scalable synchronization can be efficiently solved using reversibility of applications. Making applications reversible by relying on computation rather than on memory is ideal for large scale parallel computing, especially for the next generation of supercomputers in which memory is expensive in terms of latency, energy, and price. In this direction, a case study is presented here in reversing a computational core, namely, Basic Linear Algebra Subprograms, which is widely used in scientific applications. A new Reversible BLAS (RBLAS) library interface has been designed, and a prototype has been implemented with two modes: (1) a memory-mode in which reversibility is obtained by checkpointing to memory in forward and restoring from memory in reverse, and (2) a computational-mode in which nothing is saved in the forward, but restoration is done entirely via inverse computation in reverse. The article is focused on detailed performance benchmarking to evaluate the runtime dynamics and performance effects, comparing reversible computation with checkpointing on both traditional CPU platforms and recent GPU accelerator platforms. For BLAS Level-1 subprograms, data indicates over an order of magnitude better speed of reversible computation compared to checkpointing. For BLAS Level-2 and Level-3, a more complex tradeoff is observed between reversible computation and checkpointing, depending on computational and memory complexities of the subprograms.

  6. Towards reversible basic linear algebra subprograms: A performance study

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

    Perumalla, Kalyan S.; Yoginath, Srikanth B.

    2014-12-06

    Problems such as fault tolerance and scalable synchronization can be efficiently solved using reversibility of applications. Making applications reversible by relying on computation rather than on memory is ideal for large scale parallel computing, especially for the next generation of supercomputers in which memory is expensive in terms of latency, energy, and price. In this direction, a case study is presented here in reversing a computational core, namely, Basic Linear Algebra Subprograms, which is widely used in scientific applications. A new Reversible BLAS (RBLAS) library interface has been designed, and a prototype has been implemented with two modes: (1) amore » memory-mode in which reversibility is obtained by checkpointing to memory in forward and restoring from memory in reverse, and (2) a computational-mode in which nothing is saved in the forward, but restoration is done entirely via inverse computation in reverse. The article is focused on detailed performance benchmarking to evaluate the runtime dynamics and performance effects, comparing reversible computation with checkpointing on both traditional CPU platforms and recent GPU accelerator platforms. For BLAS Level-1 subprograms, data indicates over an order of magnitude better speed of reversible computation compared to checkpointing. For BLAS Level-2 and Level-3, a more complex tradeoff is observed between reversible computation and checkpointing, depending on computational and memory complexities of the subprograms.« less

  7. Arc fault detection system

    DOE Patents [OSTI]

    Jha, K.N.

    1999-05-18

    An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard. 1 fig.

  8. Arc fault detection system

    DOE Patents [OSTI]

    Jha, Kamal N.

    1999-01-01

    An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.

  9. Comparison of Cenozoic Faulting at the Savannah River Site to Fault Characteristics of the Atlantic Coast Fault Province: Implications for Fault Capability

    SciTech Connect (OSTI)

    Cumbest, R.J.

    2000-11-14

    This study compares the faulting observed on the Savannah River Site and vicinity with the faults of the Atlantic Coastal Fault Province and concludes that both sets of faults exhibit the same general characteristics and are closely associated. Based on the strength of this association it is concluded that the faults observed on the Savannah River Site and vicinity are in fact part of the Atlantic Coastal Fault Province. Inclusion in this group means that the historical precedent established by decades of previous studies on the seismic hazard potential for the Atlantic Coastal Fault Province is relevant to faulting at the Savannah River Site. That is, since these faults are genetically related the conclusion of ''not capable'' reached in past evaluations applies.In addition, this study establishes a set of criteria by which individual faults may be evaluated in order to assess their inclusion in the Atlantic Coast Fault Province and the related association of the ''not capable'' conclusion.

  10. The Owens Valley Fault Zone Eastern California and Surface Faulting...

    Open Energy Info (EERE)

    it steps 3 km to the left and continues northwest across Crater Mountain and through Big Pine. The fault has an overall strike of 340 and dip of 8015 ENE. Surface...

  11. Fault Detection Tool Project: Automatic Discovery of Faults using Machine

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

    Learning Fault Detection Tool Project: Automatic Discovery of Faults using Machine Learning - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization

  12. Reversible Acid Gas Capture

    ScienceCinema (OSTI)

    Dave Heldebrant

    2012-12-31

    Pacific Northwest National Laboratory scientist David Heldebrant demonstrates how a new process called reversible acid gas capture works to pull carbon dioxide out of power plant emissions.

  13. Hot Pot Detail - Evidence of Quaternary Faulting

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

    Lane, Michael

    Compilation of published data, field observations and photo interpretation relevant to Quaternary faulting at Hot Pot.

  14. Hot Pot Detail - Evidence of Quaternary Faulting

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

    Lane, Michael

    2013-06-27

    Compilation of published data, field observations and photo interpretation relevant to Quaternary faulting at Hot Pot.

  15. Cell boundary fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2009-05-05

    A method determines a nodal fault along the boundary, or face, of a computing cell. Nodes on adjacent cell boundaries communicate with each other, and the communications are analyzed to determine if a node or connection is faulty.

  16. Fault Controlled | Open Energy Information

    Open Energy Info (EERE)

    has been provided for this term. Add a Definition This classification is used if the literature describes the geothermal fluids as being controlled by faults, but not in detail....

  17. Passive fault current limiting device

    DOE Patents [OSTI]

    Evans, D.J.; Cha, Y.S.

    1999-04-06

    A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment. 6 figs.

  18. Passive fault current limiting device

    DOE Patents [OSTI]

    Evans, Daniel J.; Cha, Yung S.

    1999-01-01

    A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment.

  19. Cell boundary fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2011-04-19

    An apparatus and program product determine a nodal fault along the boundary, or face, of a computing cell. Nodes on adjacent cell boundaries communicate with each other, and the communications are analyzed to determine if a node or connection is faulty.

  20. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, John R.

    1997-01-01

    A fault current limiter (10) for an electrical circuit (14). The fault current limiter (10) includes a high temperature superconductor (12) in the electrical circuit (14). The high temperature superconductor (12) is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter (10).

  1. High temperature superconducting fault current limiter

    DOE Patents [OSTI]

    Hull, J.R.

    1997-02-04

    A fault current limiter for an electrical circuit is disclosed. The fault current limiter includes a high temperature superconductor in the electrical circuit. The high temperature superconductor is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter. 15 figs.

  2. Time reversal communication system

    DOE Patents [OSTI]

    Candy, James V.; Meyer, Alan W.

    2008-12-02

    A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

  3. Inverter Ground Fault Overvoltage Testing

    SciTech Connect (OSTI)

    Hoke, Andy; Nelson, Austin; Chakraborty, Sudipta; Chebahtah, Justin; Wang, Trudie; McCarty, Michael

    2015-08-12

    This report describes testing conducted at NREL to determine the duration and magnitude of transient overvoltages created by several commercial PV inverters during ground fault conditions. For this work, a test plan developed by the Forum on Inverter Grid Integration Issues (FIGII) has been implemented in a custom test setup at NREL. Load rejection overvoltage test results were reported previously in a separate technical report.

  4. CONTROL AND FAULT DETECTOR CIRCUIT

    DOE Patents [OSTI]

    Winningstad, C.N.

    1958-04-01

    A power control and fault detectcr circuit for a radiofrequency system is described. The operation of the circuit controls the power output of a radio- frequency power supply to automatically start the flow of energizing power to the radio-frequency power supply and to gradually increase the power to a predetermined level which is below the point where destruction occurs upon the happening of a fault. If the radio-frequency power supply output fails to increase during such period, the control does not further increase the power. On the other hand, if the output of the radio-frequency power supply properly increases, then the control continues to increase the power to a maximum value. After the maximumn value of radio-frequency output has been achieved. the control is responsive to a ''fault,'' such as a short circuit in the radio-frequency system being driven, so that the flow of power is interrupted for an interval before the cycle is repeated.

  5. Fault Current Limiters (FCL) Fact Sheet | Department of Energy

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

    Fault Current Limiters (FCL) Fact Sheet Fault Current Limiters (FCL) Fact Sheet Plugging America Into the Future of Power: Superconducting & Solid-state Power Equipment What are Fault Current Limiters Why do we need Fault Current Limiters What are the benefits to utilities Fault Current Limiter projects Fault Current Limiters (926.42 KB) More Documents & Publications An Assessment of Fault Current Limiter Testing Requirements Superconductivity Program Overview Superconductivity for

  6. Fault-tolerant dynamic task graph scheduling

    SciTech Connect (OSTI)

    Kurt, Mehmet C.; Krishnamoorthy, Sriram; Agrawal, Kunal; Agrawal, Gagan

    2014-11-16

    In this paper, we present an approach to fault tolerant execution of dynamic task graphs scheduled using work stealing. In particular, we focus on selective and localized recovery of tasks in the presence of soft faults. We elicit from the user the basic task graph structure in terms of successor and predecessor relationships. The work stealing-based algorithm to schedule such a task graph is augmented to enable recovery when the data and meta-data associated with a task get corrupted. We use this redundancy, and the knowledge of the task graph structure, to selectively recover from faults with low space and time overheads. We show that the fault tolerant design retains the essential properties of the underlying work stealing-based task scheduling algorithm, and that the fault tolerant execution is asymptotically optimal when task re-execution is taken into account. Experimental evaluation demonstrates the low cost of recovery under various fault scenarios.

  7. Directly imaging steeply-dipping fault zones in geothermal fields with multicomponent seismic data

    SciTech Connect (OSTI)

    Chen, Ting; Huang, Lianjie

    2015-07-30

    For characterizing geothermal systems, it is important to have clear images of steeply-dipping fault zones because they may confine the boundaries of geothermal reservoirs and influence hydrothermal flow. Elastic reverse-time migration (ERTM) is the most promising tool for subsurface imaging with multicomponent seismic data. However, conventional ERTM usually generates significant artifacts caused by the cross correlation of undesired wavefields and the polarity reversal of shear waves. In addition, it is difficult for conventional ERTM to directly image steeply-dipping fault zones. We develop a new ERTM imaging method in this paper to reduce these artifacts and directly image steeply-dipping fault zones. In our new ERTM method, forward-propagated source wavefields and backward-propagated receiver wavefields are decomposed into compressional (P) and shear (S) components. Furthermore, each component of these wavefields is separated into left- and right-going, or downgoing and upgoing waves. The cross correlation imaging condition is applied to the separated wavefields along opposite propagation directions. For converted waves (P-to-S or S-to-P), the polarity correction is applied to the separated wavefields based on the analysis of Poynting vectors. Numerical imaging examples of synthetic seismic data demonstrate that our new ERTM method produces high-resolution images of steeply-dipping fault zones.

  8. Directly imaging steeply-dipping fault zones in geothermal fields with multicomponent seismic data

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

    Chen, Ting; Huang, Lianjie

    2015-07-30

    For characterizing geothermal systems, it is important to have clear images of steeply-dipping fault zones because they may confine the boundaries of geothermal reservoirs and influence hydrothermal flow. Elastic reverse-time migration (ERTM) is the most promising tool for subsurface imaging with multicomponent seismic data. However, conventional ERTM usually generates significant artifacts caused by the cross correlation of undesired wavefields and the polarity reversal of shear waves. In addition, it is difficult for conventional ERTM to directly image steeply-dipping fault zones. We develop a new ERTM imaging method in this paper to reduce these artifacts and directly image steeply-dipping fault zones.more » In our new ERTM method, forward-propagated source wavefields and backward-propagated receiver wavefields are decomposed into compressional (P) and shear (S) components. Furthermore, each component of these wavefields is separated into left- and right-going, or downgoing and upgoing waves. The cross correlation imaging condition is applied to the separated wavefields along opposite propagation directions. For converted waves (P-to-S or S-to-P), the polarity correction is applied to the separated wavefields based on the analysis of Poynting vectors. Numerical imaging examples of synthetic seismic data demonstrate that our new ERTM method produces high-resolution images of steeply-dipping fault zones.« less

  9. Sandia Energy - PV Arc-Fault and Ground Fault Detection and Mitigation...

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

    prescribe maintenance schedules, and warn of arc-fault events. Investigating the proscons of module-level, string-level, and array-level arc-fault detection schemes....

  10. Detachment Faulting & Geothermal Resources - Pearl Hot Spring...

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

    Detachment Faulting & Geothermal Resources - Pearl Hot Spring, NV Finding Large Aperture Fractures in Geothermal Resource Areas Using a Three-Component Long-Offset Surface Seismic ...

  11. Efficient Synchronization Stability Metrics for Fault Clearing...

    Office of Scientific and Technical Information (OSTI)

    Title: Efficient Synchronization Stability Metrics for Fault Clearing Authors: Backhaus, Scott N. 1 ; Chertkov, Michael 1 ; Bent, Russell Whitford 1 ; Bienstock, Daniel 2...

  12. Reducing the Risk of Arc-Faults

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

    arc-fault detection algorithms by: 1. Performing arcing tests at the Distributed Energy Technologies Laboratory (DETL) with AFCI prototypes to verify their functionality on...

  13. Reversal bending fatigue testing

    SciTech Connect (OSTI)

    Wang, Jy-An John; Wang, Hong; Tan, Ting

    2014-10-21

    Embodiments for apparatuses for testing reversal bending fatigue in an elongated beam are disclosed. Embodiments are configured to be coupled to first and second end portions of the beam and to apply a bending moment to the beam and create a pure bending condition in an intermediate portion of the beam. Embodiments are further configured to cyclically alternate the direction of the bending moment applied to the beam such that the intermediate portion of the beam cyclically bends in opposite directions in a pure bending condition.

  14. Reversible brazing process

    DOE Patents [OSTI]

    Pierce, Jim D.; Stephens, John J.; Walker, Charles A.

    1999-01-01

    A method of reversibly brazing surfaces together. An interface is affixed to each surface. The interfaces can be affixed by processes such as mechanical joining, welding, or brazing. The two interfaces are then brazed together using a brazing process that does not defeat the surface to interface joint. Interfaces of materials such as Ni-200 can be affixed to metallic surfaces by welding or by brazing with a first braze alloy. The Ni-200 interfaces can then be brazed together using a second braze alloy. The second braze alloy can be chosen so that it minimally alters the properties of the interfaces to allow multiple braze, heat and disassemble, rebraze cycles.

  15. Crossing Active Faults on the Sakhalin II Onshore Pipeline Route: Analysis Methodology and Basic Design

    SciTech Connect (OSTI)

    Vitali, Luigino; Mattiozzi, Pierpaolo

    2008-07-08

    Twin oil (20 and 24 inch) and gas (20 and 48 inch) pipeline systems stretching 800 km are being constructed to connect offshore hydrocarbon deposits from the Sakhalin II concession in the North to an LNG plant and oil export terminal in the South of Sakhalin island. The onshore pipeline route follows a regional fault zone and crosses individual active faults at 19 locations. Sakhalin Energy, Design and Construction companies took significant care to ensure the integrity of the pipelines, should large seismic induced ground movements occur during the Operational life of the facilities. Complex investigations including the identification of the active faults, their precise location, their particular displacement values and assessment of the fault kinematics were carried out to provide input data for unique design solutions. Lateral and reverse offset displacements of 5.5 and 4.5 m respectively were determined as the single-event values for the design level earthquake (DLE)--the 1000-year return period event. Within the constraints of a pipeline route largely fixed, the underground pipeline fault crossing design was developed to define the optimum routing which would minimize stresses and strain using linepipe materials which had been ordered prior to the completion of detailed design, and to specify requirements for pipe trenching shape, materials, drainage system, etc. This Paper describes the steps followed to formulate the concept of the special trenches and the analytical characteristics of the Model.

  16. Crossing Active Faults on the Sakhalin II Onshore Pipeline Route: Pipeline Design and Risk Analysis

    SciTech Connect (OSTI)

    Mattiozzi, Pierpaolo; Strom, Alexander

    2008-07-08

    Twin oil (20 and 24 inch) and gas (20 and 48 inch) pipeline systems stretching 800 km are being constructed to connect offshore hydrocarbon deposits from the Sakhalin II concession in the North to an LNG plant and oil export terminal in the South of Sakhalin island. The onshore pipeline route follows a regional fault zone and crosses individual active faults at 19 locations. Sakhalin Energy, Design and Construction companies took significant care to ensure the integrity of the pipelines, should large seismic induced ground movements occur during the Operational life of the facilities. Complex investigations including the identification of the active faults, their precise location, their particular displacement values and assessment of the fault kinematics were carried out to provide input data for unique design solutions. Lateral and reverse offset displacements of 5.5 and 4.5 m respectively were determined as the single-event values for the design level earthquake (DLE) - the 1000-year return period event. Within the constraints of a pipeline route largely fixed, the underground pipeline fault crossing design was developed to define the optimum routing which would minimize stresses and strain using linepipe materials which had been ordered prior to the completion of detailed design, and to specify requirements for pipe trenching shape, materials, drainage system, etc. Detailed Design was performed with due regard to actual topography and to avoid the possibility of the trenches freezing in winter, the implementation of specific drainage solutions and thermal protection measures.

  17. Physiochemical Evidence of Faulting Processes and Modeling of Fluid in Evolving Fault Systems in Southern California

    SciTech Connect (OSTI)

    Boles, James

    2013-05-24

    Our study targets recent (Plio-Pleistocene) faults and young (Tertiary) petroleum fields in southern California. Faults include the Refugio Fault in the Transverse Ranges, the Ellwood Fault in the Santa Barbara Channel, and most recently the Newport- Inglewood in the Los Angeles Basin. Subsurface core and tubing scale samples, outcrop samples, well logs, reservoir properties, pore pressures, fluid compositions, and published structural-seismic sections have been used to characterize the tectonic/diagenetic history of the faults. As part of the effort to understand the diagenetic processes within these fault zones, we have studied analogous processes of rapid carbonate precipitation (scaling) in petroleum reservoir tubing and manmade tunnels. From this, we have identified geochemical signatures in carbonate that characterize rapid CO2 degassing. These data provide constraints for finite element models that predict fluid pressures, multiphase flow patterns, rates and patterns of deformation, subsurface temperatures and heat flow, and geochemistry associated with large fault systems.

  18. Self-triggering superconducting fault current limiter

    DOE Patents [OSTI]

    Yuan, Xing; Tekletsadik, Kasegn

    2008-10-21

    A modular and scaleable Matrix Fault Current Limiter (MFCL) that functions as a "variable impedance" device in an electric power network, using components made of superconducting and non-superconducting electrically conductive materials. The matrix fault current limiter comprises a fault current limiter module that includes a superconductor which is electrically coupled in parallel with a trigger coil, wherein the trigger coil is magnetically coupled to the superconductor. The current surge doing a fault within the electrical power network will cause the superconductor to transition to its resistive state and also generate a uniform magnetic field in the trigger coil and simultaneously limit the voltage developed across the superconductor. This results in fast and uniform quenching of the superconductors, significantly reduces the burnout risk associated with non-uniformity often existing within the volume of superconductor materials. The fault current limiter modules may be electrically coupled together to form various "n" (rows).times."m" (columns) matrix configurations.

  19. Reverse Osmosis Optimization

    SciTech Connect (OSTI)

    2013-08-01

    This technology evaluation was prepared by Pacific Northwest National Laboratory on behalf of the U.S. Department of Energy’s Federal Energy Management Program (FEMP). The technology evaluation assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. This evaluation provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. The evaluation is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system optimization options, enabling them to make informed decisions during the system design process for either new projects or recommissioning of existing equipment. This evaluation is focused on commercial-sized RO systems generally treating more than 80 gallons per hour.

  20. Reverse Osmosis Optimization

    SciTech Connect (OSTI)

    McMordie Stoughton, Kate; Duan, Xiaoli; Wendel, Emily M.

    2013-08-26

    This technology evaluation was prepared by Pacific Northwest National Laboratory on behalf of the U.S. Department of Energy’s Federal Energy Management Program (FEMP). ¬The technology evaluation assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. This evaluation provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. The evaluation is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system optimization options, enabling them to make informed decisions during the system design process for either new projects or recommissioning of existing equipment. This evaluation is focused on commercial-sized RO systems generally treating more than 80 gallons per hour.¬

  1. Multiple stimulus reversible hydrogels

    DOE Patents [OSTI]

    Gutowska, Anna; Krzyminski, Karol J.

    2006-04-25

    A polymeric solution capable of gelling upon exposure to a critical minimum value of a plurality of environmental stimuli is disclosed. The polymeric solution may be an aqueous solution utilized in vivo and capable of having the gelation reversed if at least one of the stimuli fall below, or outside the range of, the critical minimum value. The aqueous polymeric solution can be used either in industrial or pharmaceutical environments. In the medical environment, the aqueous polymeric solution is provided with either a chemical or radioisotopic therapeutic agent for delivery to a specific body part. The primary advantage of the process is that exposure to one environmental stimuli alone will not cause gelation, thereby enabling the therapeutic agent to be conducted through the body for relatively long distances without gelation occurring.

  2. Multiple stimulus reversible hydrogels

    DOE Patents [OSTI]

    Gutowska, Anna; Krzyminski, Karol J.

    2003-12-09

    A polymeric solution capable of gelling upon exposure to a critical minimum value of a plurality of environmental stimuli is disclosed. The polymeric solution may be an aqueous solution utilized in vivo and capable of having the gelation reversed if at least one of the stimuli fall below, or outside the range of, the critical minimum value. The aqueous polymeric solution can be used either in industrial or pharmaceutical environments. In the medical environment, the aqueous polymeric solution is provided with either a chemical or radioisotopic therapeutic agent for delivery to a specific body part. The primary advantage of the process is that exposure to one environmental stimuli alone will not cause gelation, thereby enabling the therapeutic agent to be conducted through the body for relatively long distances without gelation occurring.

  3. Reverse photoacoustic standoff spectroscopy

    DOE Patents [OSTI]

    Van Neste, Charles W.; Senesac, Lawrence R.; Thundat, Thomas G.

    2011-04-12

    A system and method are disclosed for generating a reversed photoacoustic spectrum at a greater distance. A source may emit a beam to a target and a detector measures signals generated as a result of the beam being emitted on the target. By emitting a chopped/pulsed light beam to the target, it may be possible to determine the target's optical absorbance by monitoring the intensity of light collected at the detector at different wavelengths. As the wavelength of light is changed, the target may absorb or reject each optical frequency. Rejection may increase the intensity at the sensing element and absorption may decrease the intensity. Accordingly, an identifying spectrum of the target may be made with the intensity variation of the detector as a function of illuminating wavelength.

  4. Reverse slapper detonator

    DOE Patents [OSTI]

    Weingart, Richard C.

    1990-01-01

    A reverse slapper detonator (70), and methodology related thereto, are provided. The detonator (70) is adapted to be driven by a pulse of electric power from an external source (80). A conductor (20) is disposed along the top (14), side (18), and bottom (16) surfaces of a sheetlike insulator (12). Part of the conductor (20) comprises a bridge (28), and an aperture (30) is positioned within the conductor (20), with the bridge (28) and the aperture (30) located on opposite sides of the insulator (12). A barrel (40) and related explosive charge (50) are positioned adjacent to and in alignment with the aperture (30), and the bridge (28) is buttressed with a backing layer (60). When the electric power pulse vaporizes the bridge (28), a portion of the insulator (12) is propelled through the aperture (30) and barrel (40), and against the explosive charge (50), thereby detonating it.

  5. Multi-fault Tolerance for Cartesian Data Distributions (Journal...

    Office of Scientific and Technical Information (OSTI)

    Fault-tolerant linear algebra (FTLA) algo- rithms employ additional processors that store parities along the dimensions of a matrix to tolerate multiple, simultaneous faults. ...

  6. Modeling of fault reactivation and induced seismicity during...

    Office of Scientific and Technical Information (OSTI)

    Modeling of fault reactivation and induced seismicity during hydraulic fracturing of shale-gas reservoirs Citation Details In-Document Search Title: Modeling of fault reactivation ...

  7. Termination of a Major Normal Fault | Open Energy Information

    Open Energy Info (EERE)

    sometimes split into multiple closely-spaced faults that result in increased permeability. Fault sets at these terminations sometimes appear as "horsetailing" splays that...

  8. Supercritical fluid reverse micelle systems

    DOE Patents [OSTI]

    Fulton, John L.; Smith, Richard D.

    1992-01-01

    of 1 ) United States Patent 5,158,704 Fulton ,   et al. October 27, 1992 Supercritical fluid reverse micelle systems

  9. Mechanical Models of Fault-Related Folding

    SciTech Connect (OSTI)

    Johnson, A. M.

    2003-01-09

    The subject of the proposed research is fault-related folding and ground deformation. The results are relevant to oil-producing structures throughout the world, to understanding of damage that has been observed along and near earthquake ruptures, and to earthquake-producing structures in California and other tectonically-active areas. The objectives of the proposed research were to provide both a unified, mechanical infrastructure for studies of fault-related foldings and to present the results in computer programs that have graphical users interfaces (GUIs) so that structural geologists and geophysicists can model a wide variety of fault-related folds (FaRFs).

  10. Reversible micromachining locator

    DOE Patents [OSTI]

    Salzer, Leander J. (Los Alamos, NM); Foreman, Larry R. (Los Alamos, NM)

    1999-01-01

    This invention provides a device which includes a locator, a kinematic mount positioned on a conventional tooling machine, a part carrier disposed on the locator and a retainer ring. The locator has disposed therein a plurality of steel balls, placed in an equidistant position circumferentially around the locator. The kinematic mount includes a plurality of magnets which are in registry with the steel balls on the locator. In operation, a blank part to be machined is placed between a surface of a locator and the retainer ring (fitting within the part carrier). When the locator (with a blank part to be machined) is coupled to the kinematic mount, the part is thus exposed for the desired machining process. Because the locator is removably attachable to the kinematic mount, it can easily be removed from the mount, reversed, and reinserted onto the mount for additional machining. Further, the locator can likewise be removed from the mount and placed onto another tooling machine having a properly aligned kinematic mount. Because of the unique design and use of magnetic forces of the present invention, positioning errors of less than 0.25 micrometer for each machining process can be achieved.

  11. Reversible micromachining locator

    DOE Patents [OSTI]

    Salzer, L.J.; Foreman, L.R.

    1999-08-31

    This invention provides a device which includes a locator, a kinematic mount positioned on a conventional tooling machine, a part carrier disposed on the locator and a retainer ring. The locator has disposed therein a plurality of steel balls, placed in an equidistant position circumferentially around the locator. The kinematic mount includes a plurality of magnets which are in registry with the steel balls on the locator. In operation, a blank part to be machined is placed between a surface of a locator and the retainer ring (fitting within the part carrier). When the locator (with a blank part to be machined) is coupled to the kinematic mount, the part is thus exposed for the desired machining process. Because the locator is removably attachable to the kinematic mount, it can easily be removed from the mount, reversed, and reinserted onto the mount for additional machining. Further, the locator can likewise be removed from the mount and placed onto another tooling machine having a properly aligned kinematic mount. Because of the unique design and use of magnetic forces of the present invention, positioning errors of less than 0.25 micrometer for each machining process can be achieved. 7 figs.

  12. PV Systems Reliability Final Technical Report: Ground Fault Detection

    SciTech Connect (OSTI)

    Lavrova, Olga; Flicker, Jack David; Johnson, Jay

    2016-01-01

    We have examined ground faults in PhotoVoltaic (PV) arrays and the efficacy of fuse, current detection (RCD), current sense monitoring/relays (CSM), isolation/insulation (Riso) monitoring, and Ground Fault Detection and Isolation (GFID) using simulations based on a Simulation Program with Integrated Circuit Emphasis SPICE ground fault circuit model, experimental ground faults installed on real arrays, and theoretical equations.

  13. HVAC Fault Detection and Diagnosis Toolkit

    Energy Science and Technology Software Center (OSTI)

    2004-12-31

    This toolkit supports component-level model-based fault detection methods in commercial building HVAC systems. The toolbox consists of five basic modules: a parameter estimator for model calibration, a preprocessor, an AHU model simulator, a steady-state detector, and a comparator. Each of these modules and the fuzzy logic rules for fault diagnosis are described in detail. The toolbox is written in C++ and also invokes the SPARK simulation program.

  14. A connecting network with fault tolerance capabilities

    SciTech Connect (OSTI)

    Ciminiera, L.; Serra, A.

    1986-06-01

    A new multistage interconnection network is presented in this paper. It is able to handle the communications between the connected devices correctly, even in the presence of fault(s) in the network. This goal is achieved by using redundant paths with a fast procedure able to dynamically reroute the message. It is also shown that the rerouting properties are still valid when broadcasting transmission is used.

  15. Development of Fault Models for Hybrid Fault Detection and Diagnostics Algorithm: October 1, 2014 -- May 5, 2015

    SciTech Connect (OSTI)

    Cheung, Howard; Braun, James E.

    2015-12-31

    This report describes models of building faults created for OpenStudio to support the ongoing development of fault detection and diagnostic (FDD) algorithms at the National Renewable Energy Laboratory. Building faults are operating abnormalities that degrade building performance, such as using more energy than normal operation, failing to maintain building temperatures according to the thermostat set points, etc. Models of building faults in OpenStudio can be used to estimate fault impacts on building performance and to develop and evaluate FDD algorithms. The aim of the project is to develop fault models of typical heating, ventilating and air conditioning (HVAC) equipment in the United States, and the fault models in this report are grouped as control faults, sensor faults, packaged and split air conditioner faults, water-cooled chiller faults, and other uncategorized faults. The control fault models simulate impacts of inappropriate thermostat control schemes such as an incorrect thermostat set point in unoccupied hours and manual changes of thermostat set point due to extreme outside temperature. Sensor fault models focus on the modeling of sensor biases including economizer relative humidity sensor bias, supply air temperature sensor bias, and water circuit temperature sensor bias. Packaged and split air conditioner fault models simulate refrigerant undercharging, condenser fouling, condenser fan motor efficiency degradation, non-condensable entrainment in refrigerant, and liquid line restriction. Other fault models that are uncategorized include duct fouling, excessive infiltration into the building, and blower and pump motor degradation.

  16. Supercritical fluid reverse micelle separation

    DOE Patents [OSTI]

    Fulton, John L.; Smith, Richard D.

    1993-01-01

    A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W.sub.o that determines the maximum size of the reverse micelles. The maximum ratio W.sub.o of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions.

  17. Supercritical fluid reverse micelle separation

    DOE Patents [OSTI]

    Fulton, J.L.; Smith, R.D.

    1993-11-30

    A method of separating solute material from a polar fluid in a first polar fluid phase is provided. The method comprises combining a polar fluid, a second fluid that is a gas at standard temperature and pressure and has a critical density, and a surfactant. The solute material is dissolved in the polar fluid to define the first polar fluid phase. The combined polar and second fluids, surfactant, and solute material dissolved in the polar fluid is maintained under near critical or supercritical temperature and pressure conditions such that the density of the second fluid exceeds the critical density thereof. In this way, a reverse micelle system defining a reverse micelle solvent is formed which comprises a continuous phase in the second fluid and a plurality of reverse micelles dispersed in the continuous phase. The solute material is dissolved in the polar fluid and is in chemical equilibrium with the reverse micelles. The first polar fluid phase and the continuous phase are immiscible. The reverse micelles each comprise a dynamic aggregate of surfactant molecules surrounding a core of the polar fluid. The reverse micelle solvent has a polar fluid-to-surfactant molar ratio W, which can vary over a range having a maximum ratio W[sub o] that determines the maximum size of the reverse micelles. The maximum ratio W[sub o] of the reverse micelle solvent is then varied, and the solute material from the first polar fluid phase is transported into the reverse micelles in the continuous phase at an extraction efficiency determined by the critical or supercritical conditions. 27 figures.

  18. Measuring and Modeling Fault Density for Plume-Fault Encounter Probability Estimation

    SciTech Connect (OSTI)

    Jordan, P.D.; Oldenburg, C.M.; Nicot, J.-P.

    2011-05-15

    Emission of carbon dioxide from fossil-fueled power generation stations contributes to global climate change. Storage of this carbon dioxide within the pores of geologic strata (geologic carbon storage) is one approach to mitigating the climate change that would otherwise occur. The large storage volume needed for this mitigation requires injection into brine-filled pore space in reservoir strata overlain by cap rocks. One of the main concerns of storage in such rocks is leakage via faults. In the early stages of site selection, site-specific fault coverages are often not available. This necessitates a method for using available fault data to develop an estimate of the likelihood of injected carbon dioxide encountering and migrating up a fault, primarily due to buoyancy. Fault population statistics provide one of the main inputs to calculate the encounter probability. Previous fault population statistics work is shown to be applicable to areal fault density statistics. This result is applied to a case study in the southern portion of the San Joaquin Basin with the result that the probability of a carbon dioxide plume from a previously planned injection had a 3% chance of encountering a fully seal offsetting fault.

  19. Fault Locating, Prediction and Protection (FLPPS)

    SciTech Connect (OSTI)

    Yinger, Robert, J.; Venkata, S., S.; Centeno, Virgilio

    2010-09-30

    One of the main objectives of this DOE-sponsored project was to reduce customer outage time. Fault location, prediction, and protection are the most important aspects of fault management for the reduction of outage time. In the past most of the research and development on power system faults in these areas has focused on transmission systems, and it is not until recently with deregulation and competition that research on power system faults has begun to focus on the unique aspects of distribution systems. This project was planned with three Phases, approximately one year per phase. The first phase of the project involved an assessment of the state-of-the-art in fault location, prediction, and detection as well as the design, lab testing, and field installation of the advanced protection system on the SCE Circuit of the Future located north of San Bernardino, CA. The new feeder automation scheme, with vacuum fault interrupters, will limit the number of customers affected by the fault. Depending on the fault location, the substation breaker might not even trip. Through the use of fast communications (fiber) the fault locations can be determined and the proper fault interrupting switches opened automatically. With knowledge of circuit loadings at the time of the fault, ties to other circuits can be closed automatically to restore all customers except the faulted section. This new automation scheme limits outage time and increases reliability for customers. The second phase of the project involved the selection, modeling, testing and installation of a fault current limiter on the Circuit of the Future. While this project did not pay for the installation and testing of the fault current limiter, it did perform the evaluation of the fault current limiter and its impacts on the protection system of the Circuit of the Future. After investigation of several fault current limiters, the Zenergy superconducting, saturable core fault current limiter was selected for

  20. Fault Detection and Load Distribution for the Wind Farm Challenge

    SciTech Connect (OSTI)

    Borchehrsen, Anders B.; Larsen, Jesper A.; Stoustrup, Jakob

    2014-08-24

    In this paper a fault detection system and a fault tolerant controller for a wind farm model. The wind farm model used is the one proposed as a public challenge. In the model three types of faults are introduced to a wind farm consisting of nine turbines. A fault detection system designed, by taking advantage of the fact that within a wind farm several wind turbines will be operating under all most identical conditions. The turbines are then grouped, and then turbines within each group are used to generate residuals for turbines in the group. The generated residuals are then evaluated using dynamical cumulative sum. The designed fault detection system is cable of detecting all three fault types occurring in the model. But there is room for improving the fault detection in some areas. To take advantage of the fault detection system a fault tolerant controller for the wind farm has been designed. The fault tolerant controller is a dispatch controller which is estimating the possible power at each individual turbine and then setting the reference accordingly. The fault tolerant controller has been compared to a reference controller. And the comparison shows that the fault tolerant controller performance better in all measures. The fault detection and a fault tolerant controller has been designed, and based on the simulated results the overall performance of the wind farm is improved on all measures. Thereby this is a step towards improving the overall performance of current and future wind farms.

  1. Rotation Reversal Bifurcation and Energy Confinement Saturation...

    Office of Scientific and Technical Information (OSTI)

    Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak OhmicL-Mode Plasmas Citation Details In-Document Search Title: Rotation Reversal Bifurcation and Energy...

  2. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Direct Imaging of Asymmetric Magnetization Reversal Print Wednesday, 28 September 2005 00:00 The phenomenon of exchange bias has...

  3. Reversible Fuel Cells Workshop | Department of Energy

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

    The workshop was divided into two sessions-a PEM reversible fuel cell session and a reversible SOFC... critical issues, materials and systems barriers, and manufacturing issues ...

  4. Buried pipelines in large fault movements

    SciTech Connect (OSTI)

    Wang, L.J.; Wang, L.R.L.

    1995-12-31

    Responses of buried pipelines in large fault movements are examined based upon a non-linear cantilever beam analogy. This analogy assumes that the pipeline in a large deflection zone behaves like a cantilever beam under a transverse-concentrated shear at the inflection point with a uniformly distributed soil pressure along the entire span. The tangent modulus approach is adopted to analyze the coupled axial force-bending moment interaction on pipeline deformations in the inelastic range. The buckling load of compressive pipeline is computed by the modified Newmark`s numerical integration scheme. Parametric studies of both tensile and compressive pipeline responses to various fault movements, pipeline/fault crossing angles, soil/pipe friction angles, buried depths, pipe diameters and thickness are investigated. It is shown by the comparisons that previous findings were unconservative.

  5. VCSEL fault location apparatus and method

    DOE Patents [OSTI]

    Keeler, Gordon A.; Serkland, Darwin K.

    2007-05-15

    An apparatus for locating a fault within an optical fiber is disclosed. The apparatus, which can be formed as a part of a fiber-optic transmitter or as a stand-alone instrument, utilizes a vertical-cavity surface-emitting laser (VCSEL) to generate a test pulse of light which is coupled into an optical fiber under test. The VCSEL is subsequently reconfigured by changing a bias voltage thereto and is used as a resonant-cavity photodetector (RCPD) to detect a portion of the test light pulse which is reflected or scattered from any fault within the optical fiber. A time interval .DELTA.t between an instant in time when the test light pulse is generated and the time the reflected or scattered portion is detected can then be used to determine the location of the fault within the optical fiber.

  6. Fault-tolerant three-level inverter

    DOE Patents [OSTI]

    Edwards, John; Xu, Longya; Bhargava, Brij B.

    2006-12-05

    A method for driving a neutral point clamped three-level inverter is provided. In one exemplary embodiment, DC current is received at a neutral point-clamped three-level inverter. The inverter has a plurality of nodes including first, second and third output nodes. The inverter also has a plurality of switches. Faults are checked for in the inverter and predetermined switches are automatically activated responsive to a detected fault such that three-phase electrical power is provided at the output nodes.

  7. Oregon Cascades Play Fairway Analysis: Faults and Heat Flow maps

    SciTech Connect (OSTI)

    Adam Brandt

    2015-11-15

    This submission includes a fault map of the Oregon Cascades and backarc, a probability map of heat flow, and a fault density probability layer. More extensive metadata can be found within each zip file.

  8. Arc-Fault Detector Algorithm Evaluation Method Utilizing Prerecorded...

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

    ... This pulse was fed into the AFD circuit to better tune the arc-fault detector. Figure 4 shows the string current (Hall Effect), the arc-fault voltage (Arc V (TEK)), and the arcing ...

  9. Deep drilling phase of the Pen Brand Fault Program

    SciTech Connect (OSTI)

    Stieve, A.

    1991-05-15

    This deep drilling activity is one element of the Pen Branch Fault Program at Savannah River Site (SRS). The effort will consist of three tasks: the extension of wells PBF-7 and PBF-8 into crystalline basement, geologic and drilling oversight during drilling operations, and the lithologic description and analysis of the recovered core. The drilling program addresses the association of the Pen Branch fault with order fault systems such as the fault that formed the Bunbarton basin in the Triassic.

  10. Adjustable direct current and pulsed circuit fault current limiter

    DOE Patents [OSTI]

    Boenig, Heinrich J.; Schillig, Josef B.

    2003-09-23

    A fault current limiting system for direct current circuits and for pulsed power circuit. In the circuits, a current source biases a diode that is in series with the circuits' transmission line. If fault current in a circuit exceeds current from the current source biasing the diode open, the diode will cease conducting and route the fault current through the current source and an inductor. This limits the rate of rise and the peak value of the fault current.

  11. Understanding Fault Characteristics of Inverter-Based Distributed Energy Resources

    SciTech Connect (OSTI)

    Keller, J.; Kroposki, B.

    2010-01-01

    This report discusses issues and provides solutions for dealing with fault current contributions from inverter-based distributed energy resources.

  12. All row, planar fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D; Smith, Brian Edward

    2013-07-23

    An apparatus, program product and method for detecting nodal faults may simultaneously cause designated nodes of a cell to communicate with all nodes adjacent to each of the designated nodes. Furthermore, all nodes along the axes of the designated nodes are made to communicate with their adjacent nodes, and the communications are analyzed to determine if a node or connection is faulty.

  13. Multi-directional fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2009-03-17

    An apparatus, program product and method checks for nodal faults in a group of nodes comprising a center node and all adjacent nodes. The center node concurrently communicates with the immediately adjacent nodes in three dimensions. The communications are analyzed to determine a presence of a faulty node or connection.

  14. Multi-directional fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-11-23

    An apparatus, program product and method checks for nodal faults in a group of nodes comprising a center node and all adjacent nodes. The center node concurrently communicates with the immediately adjacent nodes in three dimensions. The communications are analyzed to determine a presence of a faulty node or connection.

  15. Multi-directional fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-06-29

    An apparatus, program product and method checks for nodal faults in a group of nodes comprising a center node and all adjacent nodes. The center node concurrently communicates with the immediately adjacent nodes in three dimensions. The communications are analyzed to determine a presence of a faulty node or connection.

  16. Coordinated Fault Tolerance for High-Performance Computing

    SciTech Connect (OSTI)

    Dongarra, Jack; Bosilca, George; et al.

    2013-04-08

    Our work to meet our goal of end-to-end fault tolerance has focused on two areas: (1) improving fault tolerance in various software currently available and widely used throughout the HEC domain and (2) using fault information exchange and coordination to achieve holistic, systemwide fault tolerance and understanding how to design and implement interfaces for integrating fault tolerance features for multiple layers of the software stack—from the application, math libraries, and programming language runtime to other common system software such as jobs schedulers, resource managers, and monitoring tools.

  17. Reverse engineering of integrated circuits

    DOE Patents [OSTI]

    Chisholm, Gregory H.; Eckmann, Steven T.; Lain, Christopher M.; Veroff, Robert L.

    2003-01-01

    Software and a method therein to analyze circuits. The software comprises several tools, each of which perform particular functions in the Reverse Engineering process. The analyst, through a standard interface, directs each tool to the portion of the task to which it is most well suited, rendering previously intractable problems solvable. The tools are generally used iteratively to produce a successively more abstract picture of a circuit, about which incomplete a priori knowledge exists.

  18. Statistical Fault Detection & Diagnosis Expert System

    Energy Science and Technology Software Center (OSTI)

    1996-12-18

    STATMON is an expert system that performs real-time fault detection and diagnosis of redundant sensors in any industrial process requiring high reliability. After a training period performed during normal operation, the expert system monitors the statistical properties of the incoming signals using a pattern recognition test. If the test determines that statistical properties of the signals have changed, the expert system performs a sequence of logical steps to determine which sensor or machine component hasmoredegraded.less

  19. Undulator Hall Air Temperature Fault Scenarios

    SciTech Connect (OSTI)

    Sevilla, J.; Welch, J.; ,

    2010-11-17

    Recent experience indicates that the LCLS undulator segments must not, at any time following tuning, be allowed to change temperature by more than about {+-}2.5 C or the magnetic center will irreversibly shift outside of acceptable tolerances. This vulnerability raises a concern that under fault conditions the ambient temperature in the Undulator Hall might go outside of the safe range and potentially could require removal and retuning of all the segments. In this note we estimate changes that can be expected in the Undulator Hall air temperature for three fault scenarios: (1) System-wide power failure; (2) Heating Ventilation and Air Conditioning (HVAC) system shutdown; and (3) HVAC system temperature regulation fault. We find that for either a system-wide power failure or an HVAC system shutdown (with the technical equipment left on), the short-term temperature changes of the air would be modest due to the ability of the walls and floor to act as a heat ballast. No action would be needed to protect the undulator system in the event of a system-wide power failure. Some action to adjust the heat balance, in the case of the HVAC power failure with the equipment left on, might be desirable but is not required. On the other hand, a temperature regulation failure of the HVAC system can quickly cause large excursions in air temperature and prompt action would be required to avoid damage to the undulator system.

  20. Calculating the probability of injected carbon dioxide plumes encountering faults

    SciTech Connect (OSTI)

    Jordan, P.D.

    2011-04-01

    One of the main concerns of storage in saline aquifers is leakage via faults. In the early stages of site selection, site-specific fault coverages are often not available for these aquifers. This necessitates a method using available fault data to estimate the probability of injected carbon dioxide encountering and migrating up a fault. The probability of encounter can be calculated from areal fault density statistics from available data, and carbon dioxide plume dimensions from numerical simulation. Given a number of assumptions, the dimension of the plume perpendicular to a fault times the areal density of faults with offsets greater than some threshold of interest provides probability of the plume encountering such a fault. Application of this result to a previously planned large-scale pilot injection in the southern portion of the San Joaquin Basin yielded a 3% and 7% chance of the plume encountering a fully and half seal offsetting fault, respectively. Subsequently available data indicated a half seal-offsetting fault at a distance from the injection well that implied a 20% probability of encounter for a plume sufficiently large to reach it.

  1. Detachment faults: Evidence for a low-angle origin

    SciTech Connect (OSTI)

    Scott, R.J.; Lister, G.S. )

    1992-09-01

    The origin of low-angle normal faults or detachment faults mantling metamorphic core complexes in the southwestern United States remains controversial. If [sigma][sub 1] is vertical during extension, the formation of, or even slip along, such low-angle normal faults is mechanically implausible. No records exist of earthquakes on low-angle normal faults in areas currently undergoing continental extension, except from an area of actively forming core complexes in the Solomon Sea, Papua New Guinea. In light of such geophysical and mechanical arguments, W.R. Buck and B. Wernicke and G.J. Axen proposed models in which detachment faults originate as high-angle normal faults, but rotate to low angles and become inactive as extension proceeds. These models are inconsistent with critical field relations in several core complexes. The Rawhide fault, an areally extensive detachment fault in western Arizona, propagated at close to its present subhorizontal orientation late in the Tertiary extension of the region. Neither the Wernicke and Axen nor Buck models predict such behavior; in fact, both models preclude the operation of low-angle normal faults. The authors recommend that alternative explanations or modifications of existing models are needed to explain the evidence that detachment faults form and operate with gentle dips.

  2. Remote Whispering Applying Time Reversal

    SciTech Connect (OSTI)

    Anderson, Brian Eric

    2015-07-16

    The purpose of this project was to explore the use of time reversal technologies as a means for communication to a targeted individual or location. The idea is to have the privacy of whispering in one’s ear, but to do this remotely from loudspeakers not located near the target. Applications of this work include communicating with hostages and survivors in rescue operations, communicating imaging and operational conditions in deep drilling operations, monitoring storage of spent nuclear fuel in storage casks without wires, or clandestine activities requiring signaling between specific points. This technology provides a solution in any application where wires and radio communications are not possible or not desired. It also may be configured to self calibrate on a regular basis to adjust for changing conditions. These communications allow two people to converse with one another in real time, converse in an inaudible frequency range or medium (i.e. using ultrasonic frequencies and/or sending vibrations through a structure), or send information for a system to interpret (even allowing remote control of a system using sound). The time reversal process allows one to focus energy to a specific location in space and to send a clean transmission of a selected signal only to that location. In order for the time reversal process to work, a calibration signal must be obtained. This signal may be obtained experimentally using an impulsive sound, a known chirp signal, or other known signals. It may also be determined from a numerical model of a known environment in which the focusing is desired or from passive listening over time to ambient noise.

  3. Reversible Fuel Cells Workshop Summary Report | Department of...

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

    Reversible Fuel Cells Workshop Summary Report Reversible Fuel Cells Workshop Summary Report Summary and presentations from the NREL Reversible Fuel Cells Workshop held April 19, ...

  4. Development of Reversible Fuel Cell Systems at Proton Energy

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

    Reversible Fuel Cell Systems at Proton Energy Everett Anderson NRELDOE Reversible Fuel Cell Workshop 19 April 2011 Development of Reversible Fuel Cell Systems at Proton Energy ...

  5. Fault-Oblivious Exascale Computing Environment | Argonne Leadership

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

    Computing Facility Fault-Oblivious Exascale Computing Environment PI Name: Maya B. Gokhale PI Email: gokhale2@llnl.gov Allocation Program: INCITE Allocation Hours at ALCF: 10,000,000 Year: 2012 Research Domain: Computer Science Two areas of concern that have emerged from several DOE meetings on exascale systems (machines with 100 million cores) are runtime systems which can function at that scale, and fault management. The Fault Oblivious Exascale (FOX) project aims to build a software stack

  6. An Assessment of Fault Current Limiter Testing Requirements | Department of

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

    Energy Fault Current Limiter Testing Requirements An Assessment of Fault Current Limiter Testing Requirements The U.S. Department of Energy's (DOE) Office of Electricity Delivery and Energy Reliability (OE) is conducting research and development (R&D) on next-generation electricity delivery equipment including fault current limiters (FCLs). Prototype FCL devices are undergoing testing with the aim of market-ready devices making their debut in the transmission and distribution (T&D)

  7. Properties of the extra stage cube under multiple faults

    SciTech Connect (OSTI)

    Adams, G.B., III; Siegel, H.J.

    1982-01-01

    The extra stage cube (ESC) interconnection network, a fault tolerant structure, has been proposed for use in large-scale parallel and distributed systems. It has all of the interconnecting capabilities of the multistage cube-type networks that have been proposed for many systems, and the ESC provides fault tolerance for any single failure. The paper examines the ability of the ESC to operate with multiple faults. 9 references.

  8. Recency of Faulting and Neotectonic Framework in the Dixie Valley...

    Open Energy Info (EERE)

    by active geothermal springs. More specifically, our investigation shows that induced stress concentrations at the endpoints of normal fault ruptures appear to promote favorable...

  9. Error Estimation for Fault Tolerance in Numerical Integration...

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

    Error Estimation for Fault Tolerance in Numerical Integration Solvers Event Sponsor: ... In numerical integration solvers, approximation error can be estimated at a low cost. We ...

  10. Understanding Fault Characteristics And Sediment Depth For Geothermal...

    Open Energy Info (EERE)

    Understanding Fault Characteristics And Sediment Depth For Geothermal Exploration Using 3D Gravity Inversion In Walker Valley, Nevada Jump to: navigation, search OpenEI Reference...

  11. Microsoft PowerPoint - HPC - Resilience-Fault Injection Research...

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

    This document is approved for public release; further dissemination unlimited Resilience ... FIT 32Gbit High FIT 32Gbit Low FIT Resilience Fault Injection Research ...

  12. Upper crustal faulting in an obliquely extending orogen, structural...

    Open Energy Info (EERE)

    faulting in an obliquely extending orogen, structural control on permeability and production in the Coso Geothermal Field, eastern California Jump to: navigation, search OpenEI...

  13. Active Fault Controls At High-Temperature Geothermal Sites- Prospectin...

    Open Energy Info (EERE)

    model in which recently active (Holocene) faults are preferred conduits for migration of thermal water from deep crustal depths, and we infer that the detection of sites...

  14. Active Fault Segments As Potential Earthquake Sources- Inferences...

    Open Energy Info (EERE)

    Segments As Potential Earthquake Sources- Inferences From Integrated Geophysical Mapping Of The Magadi Fault System, Southern Kenya Rift Jump to: navigation, search OpenEI...

  15. Controls on Fault-Hosted Fluid Flow: Preliminary Results from...

    Open Energy Info (EERE)

    Flow: Preliminary Results from the Coso Geothermal Field, CA Abstract cap rock, permeability, fault, fracture, clay, Coso Authors Davatzes, N.C.; Hickman and S.H. Published...

  16. Dating of major normal fault systems using thermochronology-...

    Open Energy Info (EERE)

    Dating of major normal fault systems using thermochronology- An example from the Raft River detachment, Basin and Range, western United States Jump to: navigation, search OpenEI...

  17. Fault Mapping At Raft River Geothermal Area (1993) | Open Energy...

    Open Energy Info (EERE)

    Raft River Geothermal Area (1993) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Fault Mapping At Raft River Geothermal Area (1993) Exploration...

  18. Asking the right questions: benchmarking fault-tolerant extreme...

    Office of Scientific and Technical Information (OSTI)

    Title: Asking the right questions: benchmarking fault-tolerant extreme-scale systems. Abstract not provided. Authors: Widener, Patrick ; Ferreira, Kurt Brian ; Levy, Scott N. ; ...

  19. Statistical Fault Detection & Diagnosis Expert System

    Energy Science and Technology Software Center (OSTI)

    1996-12-18

    STATMON is an expert system that performs real-time fault detection and diagnosis of redundant sensors in any industrial process requiring high reliability. After a training period performed during normal operation, the expert system monitors the statistical properties of the incoming signals using a pattern recognition test. If the test determines that statistical properties of the signals have changed, the expert system performs a sequence of logical steps to determine which sensor or machine component hasmore » degraded.« less

  20. Superconducting fault current controller/current controller

    DOE Patents [OSTI]

    Cha, Yung S.

    2004-06-15

    A superconducting fault current controller/current controller employs a superconducting-shielded core reactor (SSCR) with a variable impedance in a secondary circuit to control current in a primary circuit such as an electrical distribution system. In a second embodiment, a variable current source is employed in a secondary circuit of an SSCR to control current in the primary circuit. In a third embodiment, both a variable impedance in one secondary circuit and a variable current source in a second circuit of an SSCR are employed for separate and independent control of current in the primary circuit.

  1. Process of forming compounds using reverse micelle or reverse microemulsion systems

    DOE Patents [OSTI]

    Linehan, John C.; Fulton, John L.; Bean, Roger M.

    1998-01-01

    The present invention is directed to a process for producing a nanometer-sized metal compound. The process comprises forming a reverse micelle or reverse microemulsion system comprising a polar fluid in a non-polar or low-polarity fluid. A first reactant comprising a multi-component, water-soluble metal compound is introduced into the polar fluid in a non-polar or low-polarity fluid. This first reactant can be introduced into the reverse micelle or reverse microemulsion system during formation thereof or subsequent to the formation of the reverse micelle or microemulsion system. The water-soluble metal compound is then reacted in the reverse micelle or reverse microemulsion system to form the nanometer-sized metal compound. The nanometer-sized metal compound is then precipitated from the reverse micelle or reverse microemulsion system.

  2. All-to-all sequenced fault detection system

    DOE Patents [OSTI]

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-11-02

    An apparatus, program product and method enable nodal fault detection by sequencing communications between all system nodes. A master node may coordinate communications between two slave nodes before sequencing to and initiating communications between a new pair of slave nodes. The communications may be analyzed to determine the nodal fault.

  3. Folding associated with extensional faulting: Sheep Range detachment, southern Nevada

    SciTech Connect (OSTI)

    Guth, P.L.

    1985-01-01

    The Sheep Range detachment is a major Miocene extensional fault system of the Great Basin. Its major faults have a scoop shape, with straight, N-S traces extending 15-30 km and then abruptly turning to strike E-W. Tertiary deformation involved simultaneous normal faulting, sedimentation, landsliding, and strike-slip faulting. Folds occur in two settings: landslide blocks and drag along major faults. Folds occur in landslide blocks and beneath them. Most folds within landslide blocks are tight anticlines, with limbs dipping 40-60 degrees. Brecciation of the folds and landslide blocks suggests brittle deformation. Near Quijinump Canyon in the Sheep Range, at least three landslide blocks (up to 500 by 1500 m) slid into a small Tertiary basin. Tertiary limestone beneath the Paleozoic blocks was isoclinally folded. Westward dips reveal drag folds along major normal faults, as regional dips are consistently to the east. The Chowderhead anticline is the largest drag fold, along an extensional fault that offsets Ordovician units 8 km. East-dipping Ordovician and Silurian rocks in the Desert Range form the hanging wall. East-dipping Cambrian and Ordovician units in the East Desert Range form the foot wall and east limb of the anticline. Caught along the fault plane, the anticline's west-dipping west limb contains mostly Cambrian units.

  4. Fault current limiter with shield and adjacent cores

    DOE Patents [OSTI]

    Darmann, Francis Anthony; Moriconi, Franco; Hodge, Eoin Patrick

    2013-10-22

    In a fault current limiter (FCL) of a saturated core type having at least one coil wound around a high permeability material, a method of suppressing the time derivative of the fault current at the zero current point includes the following step: utilizing an electromagnetic screen or shield around the AC coil to suppress the time derivative current levels during zero current conditions.

  5. Automated Proactive Fault Isolation: A Key to Automated Commissioning

    SciTech Connect (OSTI)

    Katipamula, Srinivas; Brambley, Michael R.

    2007-07-31

    In this paper, we present a generic model for automated continuous commissioing and then delve in detail into one of the processes, proactive testing for fault isolation, which is key to automating commissioning. The automated commissioining process uses passive observation-based fault detction and diagnostic techniques, followed by automated proactive testing for fault isolation, automated fault evaluation, and automated reconfiguration of controls together to continuously keep equipment controlled and running as intended. Only when hard failures occur or a physical replacement is required does the process require human intervention, and then sufficient information is provided by the automated commissioning system to target manual maintenance where it is needed. We then focus on fault isolation by presenting detailed logic that can be used to automatically isolate faults in valves, a common component in HVAC systems, as an example of how automated proactive fault isolation can be accomplished. We conclude the paper with a discussion of how this approach to isolating faults can be applied to other common HVAC components and their automated commmissioning and a summary of key conclusions of the paper.

  6. Automatic Fault Characterization via Abnormality-Enhanced Classification

    SciTech Connect (OSTI)

    Bronevetsky, G; Laguna, I; de Supinski, B R

    2010-12-20

    Enterprise and high-performance computing systems are growing extremely large and complex, employing hundreds to hundreds of thousands of processors and software/hardware stacks built by many people across many organizations. As the growing scale of these machines increases the frequency of faults, system complexity makes these faults difficult to detect and to diagnose. Current system management techniques, which focus primarily on efficient data access and query mechanisms, require system administrators to examine the behavior of various system services manually. Growing system complexity is making this manual process unmanageable: administrators require more effective management tools that can detect faults and help to identify their root causes. System administrators need timely notification when a fault is manifested that includes the type of fault, the time period in which it occurred and the processor on which it originated. Statistical modeling approaches can accurately characterize system behavior. However, the complex effects of system faults make these tools difficult to apply effectively. This paper investigates the application of classification and clustering algorithms to fault detection and characterization. We show experimentally that naively applying these methods achieves poor accuracy. Further, we design novel techniques that combine classification algorithms with information on the abnormality of application behavior to improve detection and characterization accuracy. Our experiments demonstrate that these techniques can detect and characterize faults with 65% accuracy, compared to just 5% accuracy for naive approaches.

  7. Reverse Osmosis Optimization | Department of Energy

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

    Reverse Osmosis Optimization Reverse Osmosis Optimization Report assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. It provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. This report is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system

  8. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Direct Imaging of Asymmetric Magnetization Reversal Print Wednesday, 28 September 2005 00:00 The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron

  9. Gravity controlled anti-reverse rotation device

    DOE Patents [OSTI]

    Dickinson, Robert J.; Wetherill, Todd M.

    1983-01-01

    A gravity assisted anti-reverse rotation device for preventing reverse rotation of pumps and the like. A horizontally mounted pawl is disposed to mesh with a fixed ratchet preventing reverse rotation when the pawl is advanced into intercourse with the ratchet by a vertically mounted lever having a lumped mass. Gravitation action on the lumped mass urges the pawl into mesh with the ratchet, while centrifugal force on the lumped mass during forward, allowed rotation retracts the pawl away from the ratchet.

  10. Time Reversal of Bose-Einstein Condensates

    SciTech Connect (OSTI)

    Martin, J.; Georgeot, B.; Shepelyansky, D. L. [Laboratoire de Physique Theorique, Universite de Toulouse III, CNRS, 31062 Toulouse (France)

    2008-08-15

    Using Gross-Pitaevskii equation, we study the time reversibility of Bose-Einstein condensates (BEC) in kicked optical lattices, showing that in the regime of quantum chaos, the dynamics can be inverted from explosion to collapse. The accuracy of time reversal decreases with the increase of atom interactions in BEC, until it is completely lost. Surprisingly, quantum chaos helps to restore time reversibility. These predictions can be tested with existing experimental setups.

  11. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their...

  12. Rotation Reversal Bifurcation and Energy Confinement Saturation...

    Office of Scientific and Technical Information (OSTI)

    Title: Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L -Mode Plasmas Authors: Rice, J. E. ; Cziegler, I. ; Diamond, P. H. ; Duval, B. P. ; ...

  13. Locating an active fault zone in Coso geothermal field by analyzing...

    Open Energy Info (EERE)

    waves from microearthquake data Abstract Active fault systems usually provide high-permeability channels for hydrothermal outflow in geothermal fields. Locating such fault systems...

  14. Self field triggered superconducting fault current limiter

    DOE Patents [OSTI]

    Tekletsadik, Kasegn D.

    2008-02-19

    A superconducting fault current limiter array with a plurality of superconductor elements arranged in a meanding array having an even number of supconductors parallel to each other and arranged in a plane that is parallel to an odd number of the plurality of superconductors, where the odd number of supconductors are parallel to each other and arranged in a plane that is parallel to the even number of the plurality of superconductors, when viewed from a top view. The even number of superconductors are coupled at the upper end to the upper end of the odd number of superconductors. A plurality of lower shunt coils each coupled to the lower end of each of the even number of superconductors and a plurality of upper shunt coils each coupled to the upper end of each of the odd number of superconductors so as to generate a generally orthoganal uniform magnetic field during quenching using only the magenetic field generated by the superconductors.

  15. Locating hardware faults in a parallel computer

    DOE Patents [OSTI]

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-04-13

    Locating hardware faults in a parallel computer, including defining within a tree network of the parallel computer two or more sets of non-overlapping test levels of compute nodes of the network that together include all the data communications links of the network, each non-overlapping test level comprising two or more adjacent tiers of the tree; defining test cells within each non-overlapping test level, each test cell comprising a subtree of the tree including a subtree root compute node and all descendant compute nodes of the subtree root compute node within a non-overlapping test level; performing, separately on each set of non-overlapping test levels, an uplink test on all test cells in a set of non-overlapping test levels; and performing, separately from the uplink tests and separately on each set of non-overlapping test levels, a downlink test on all test cells in a set of non-overlapping test levels.

  16. Online Monitoring System for Performance Fault Detection

    SciTech Connect (OSTI)

    Gioiosa, Roberto; Kestor, Gokcen; Kerbyson, Darren J.

    2014-05-19

    To achieve the exaFLOPS performance within a contain power budget, next supercomputers will feature hundreds of millions of components operating at low- and near-threshold voltage. As the probability that at least one of these components fails during the execution of an application approaches certainty, it seems unrealistic to expect that any run of a scientific application will not experience some performance faults. We believe that there is need of a new generation of light-weight performance and debugging tools that can be used online even during production runs of parallel applications and that can identify performance anomalies during the application execution. In this work we propose the design and implementation of a monitoring system that continuously inspects the evolution of run

  17. Anastomosing grabens, low-angle faults, and Tertiary thrust( ) faults, western Markagunt Plateau, southwestern Utah

    SciTech Connect (OSTI)

    Maldonado, F.; Sable, E.G. )

    1993-04-01

    A structurally complex terrane composed of grabens and horsts, low-angle faults, Tertiary thrust( ) faults, gravity-slide blocks, and debris deposits has been mapped along the western Markagunt Plateau, east of Parowan and Summit, southwestern Utah. This terrane, structurally situated within the transition between the Basin and Range and Colorado Plateau provinces, contains Tertiary volcanic and sedimentary and Cretaceous sedimentary rocks. The structures are mostly Miocene to Oligocene but some are Pleistocene. The oldest structure is the Red Hills low-angle shear zone, interpreted as a shallow structure that decoupled an upper plate composed of a Miocene-Oligocene volcanic ash-flow tuff and volcaniclastic succession from a lower plate of Tertiary sedimentary rocks. The period of deformation on the shear zone is bracketed from field relationships between 22.5 and 20 Ma. The graben-horst system trends northeast and formed after about 20 Ma (and probably much later) based on displacement of dated dikes and a laccolith. The central part of the system contains many grabens that merge toward its southerly end to become a single graben. Within these grabens, (1) older structures are preserved, (2) debris eroded from horst walls forms lobe-shaped deposits, (3) Pleistocene basaltic cinder cones have localized along graben-bounding faults, and (4) rock units are locally folded suggesting some component of lateral translation along graben-bounding faults. Megabreccia deposits and landslide debris are common. Megabreccia deposits are interpreted as gravity-slide blocks of Miocene-Oligocene( ) age resulting from formation of the Red Hills shear zone, although some may be related to volcanism, and still others to later deformation. The debris deposits are landslides of Pleistocene-Pliocene( ) age possibly caused by continued uplift of the Markagunt Plateau.

  18. Fuel cell system with coolant flow reversal

    DOE Patents [OSTI]

    Kothmann, Richard E. (Pittsburgh, PA)

    1986-01-01

    Method and apparatus for cooling electrochemical fuel cell system components. Periodic reversal of the direction of flow of cooling fluid through a fuel cell stack provides greater uniformity and cell operational temperatures. Flow direction through a recirculating coolant fluid circuit is reversed through a two position valve, without requiring modulation of the pumping component.

  19. Three component vibrational time reversal communication

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

    Anderson, Brian E.; Ulrich, Timothy J.; Ten Cate, James A.

    2015-01-01

    Time reversal provides an optimal prefilter matched signal to apply to a communication signal before signal transmission. Time reversal allows compensation for wave speed dispersion and can function well in reverberant environments. Time reversal can be used to focus elastic energy to each of the three components of motion independently. A pipe encased in concrete was used to demonstrate the ability to conduct communications of information using three component time reversal. Furthermore, the ability of time reversal to compensate for multi-path distortion (overcoming reverberation) will be demonstrated and the rate of signal communication will be presented. [The U.S. Department ofmore » Energy, through the LANL/LDRD Program, is gratefully acknowledged for supporting this work.]« less

  20. Development of Characterization Technology for Fault Zone Hydrology

    SciTech Connect (OSTI)

    Karasaki, Kenzi; Onishi, Tiemi; Gasperikova, Erika; Goto, Junichi; Tsuchi, Hiroyuki; Miwa, Tadashi; Ueta, Keiichi; Kiho, Kenzo; MIyakawa, Kimio

    2010-08-06

    Several deep trenches were cut, and a number of geophysical surveys were conducted across the Wildcat Fault in the hills east of Berkeley, California. The Wildcat Fault is believed to be a strike-slip fault and a member of the Hayward Fault System, with over 10 km of displacement. So far, three boreholes of ~;; 150m deep have been core-drilled and borehole geophysical logs were conducted. The rocks are extensively sheared and fractured; gouges were observed at several depths and a thick cataclasitic zone was also observed. While confirming some earlier, published conclusions from shallow observations about Wildcat, some unexpected findings were encountered. Preliminary analysis indicates that Wildcat near the field site consists of multiple faults. The hydraulic test data suggest the dual properties of the hydrologic structure of the fault zone. A fourth borehole is planned to penetrate the main fault believed to lie in-between the holes. The main philosophy behind our approach for the hydrologic characterization of such a complex fractured system is to let the system take its own average and monitor a long term behavior instead of collecting a multitude of data at small length and time scales, or at a discrete fracture scale and to ?up-scale,? which is extremely tenuous.

  1. Chemical reactions in reverse micelle systems

    DOE Patents [OSTI]

    Matson, Dean W.; Fulton, John L.; Smith, Richard D.; Consani, Keith A.

    1993-08-24

    This invention is directed to conducting chemical reactions in reverse micelle or microemulsion systems comprising a substantially discontinuous phase including a polar fluid, typically an aqueous fluid, and a microemulsion promoter, typically a surfactant, for facilitating the formation of reverse micelles in the system. The system further includes a substantially continuous phase including a non-polar or low-polarity fluid material which is a gas under standard temperature and pressure and has a critical density, and which is generally a water-insoluble fluid in a near critical or supercritical state. Thus, the microemulsion system is maintained at a pressure and temperature such that the density of the non-polar or low-polarity fluid exceeds the critical density thereof. The method of carrying out chemical reactions generally comprises forming a first reverse micelle system including an aqueous fluid including reverse micelles in a water-insoluble fluid in the supercritical state. Then, a first reactant is introduced into the first reverse micelle system, and a chemical reaction is carried out with the first reactant to form a reaction product. In general, the first reactant can be incorporated into, and the product formed in, the reverse micelles. A second reactant can also be incorporated in the first reverse micelle system which is capable of reacting with the first reactant to form a product.

  2. Cheaper Adjoints by Reversing Address Computations

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

    Hascoët, L.; Utke, J.; Naumann, U.

    2008-01-01

    The reverse mode of automatic differentiation is widely used in science and engineering. A severe bottleneck for the performance of the reverse mode, however, is the necessity to recover certain intermediate values of the program in reverse order. Among these values are computed addresses, which traditionally are recovered through forward recomputation and storage in memory. We propose an alternative approach for recovery that uses inverse computation based on dependency information. Address storage constitutes a significant portion of the overall storage requirements. An example illustrates substantial gains that the proposed approach yields, and we show use cases in practical applications.

  3. Analysis of the growth of strike-slip faults using effective medium theory

    SciTech Connect (OSTI)

    Aydin, A.; Berryman, J.G.

    2009-10-15

    Increases in the dimensions of strike-slip faults including fault length, thickness of fault rock and the surrounding damage zone collectively provide quantitative definition of fault growth and are commonly measured in terms of the maximum fault slip. The field observations indicate that a common mechanism for fault growth in the brittle upper crust is fault lengthening by linkage and coalescence of neighboring fault segments or strands, and fault rock-zone widening into highly fractured inner damage zone via cataclastic deformation. The most important underlying mechanical reason in both cases is prior weakening of the rocks surrounding a fault's core and between neighboring fault segments by faulting-related fractures. In this paper, using field observations together with effective medium models, we analyze the reduction in the effective elastic properties of rock in terms of density of the fault-related brittle fractures and fracture intersection angles controlled primarily by the splay angles. Fracture densities or equivalent fracture spacing values corresponding to the vanishing Young's, shear, and quasi-pure shear moduli were obtained by extrapolation from the calculated range of these parameters. The fracture densities or the equivalent spacing values obtained using this method compare well with the field data measured along scan lines across the faults in the study area. These findings should be helpful for a better understanding of the fracture density/spacing distribution around faults and the transition from discrete fracturing to cataclastic deformation associated with fault growth and the related instabilities.

  4. Coupled hydro-mechanical processes and fault reactivation induced...

    Office of Scientific and Technical Information (OSTI)

    Coupled hydro-mechanical processes and fault reactivation induced by Co2 Injection in a three-layer storage formation Citation Details In-Document Search This content will become ...

  5. Recent earthquake sequences at Coso: Evidence for conjugate faulting...

    Open Energy Info (EERE)

    earthquake sequences at Coso: Evidence for conjugate faulting and stress loading near a geothermal field Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal...

  6. STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND...

    Open Energy Info (EERE)

    STRESS AND FAULTING IN THE COSO GEOTHERMAL FIELD: UPDATE AND RECENT RESULTS FROM THE EAST FLANK AND COSO WASH Jump to: navigation, search OpenEI Reference LibraryAdd to library...

  7. INVESTIGATION OF HOLOCENE FAULTING PROPOSED C-746-U LANDFILL EXPANSION

    SciTech Connect (OSTI)

    Lettis, William

    2006-07-01

    This report presents the findings of a fault hazard investigation for the C-746-U landfill's proposed expansion located at the Department of Energy's (DOE) Paducah Gaseous Diffusion Plant (PGDP), in Paducah, Kentucky. The planned expansion is located directly north of the present-day C-746-U landfill. Previous geophysical studies within the PGDP site vicinity interpret possible northeast-striking faults beneath the proposed landfill expansion, although prior to this investigation the existence, locations, and ages of these inferred faults have not been confirmed through independent subsurface exploration. The purpose of this investigation is to assess whether or not Holocene-active fault displacement is present beneath the footprint of the proposed landfill expansion.

  8. Fault Tree Reliability Analysis and Design-for-reliability

    Energy Science and Technology Software Center (OSTI)

    1998-05-05

    WinR provides a fault tree analysis capability for performing systems reliability and design-for-reliability analyses. The package includes capabilities for sensitivity and uncertainity analysis, field failure data analysis, and optimization.

  9. Fault and joint geometry at Raft River geothermal area, Idaho...

    Open Energy Info (EERE)

    may be useful for locating the surface traces of faults in the reservoir. Authors Guth, L. R.; Bruhn, R. L.; Beck and S. L. Published DOE Information Bridge, 711981 DOI...

  10. High-Resolution Aeromagnetic Survey to Image Shallow Faults,...

    Open Energy Info (EERE)

    to Image Shallow Faults, Dixie Valley Geothermal Field, Nevada Abstract NA Author V. J. S. Grauch Published U.S. Geological Survey, 2002 Report Number 02-384 DOI Not Provided...

  11. Exploiting data representation for fault tolerance

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

    Hoemmen, Mark Frederick; Elliott, J.; Sandia National Lab.; Mueller, F.

    2015-01-06

    Incorrect computer hardware behavior may corrupt intermediate computations in numerical algorithms, possibly resulting in incorrect answers. Prior work models misbehaving hardware by randomly flipping bits in memory. We start by accepting this premise, and present an analytic model for the error introduced by a bit flip in an IEEE 754 floating-point number. We then relate this finding to the linear algebra concepts of normalization and matrix equilibration. In particular, we present a case study illustrating that normalizing both vector inputs of a dot product minimizes the probability of a single bit flip causing a large error in the dot product'smore » result. Moreover, the absolute error is either less than one or very large, which allows detection of large errors. Then, we apply this to the GMRES iterative solver. We count all possible errors that can be introduced through faults in arithmetic in the computationally intensive orthogonalization phase of GMRES, and show that when the matrix is equilibrated, the absolute error is bounded above by one.« less

  12. Exploiting data representation for fault tolerance

    SciTech Connect (OSTI)

    Hoemmen, Mark Frederick; Elliott, J.; Mueller, F.

    2015-01-06

    Incorrect computer hardware behavior may corrupt intermediate computations in numerical algorithms, possibly resulting in incorrect answers. Prior work models misbehaving hardware by randomly flipping bits in memory. We start by accepting this premise, and present an analytic model for the error introduced by a bit flip in an IEEE 754 floating-point number. We then relate this finding to the linear algebra concepts of normalization and matrix equilibration. In particular, we present a case study illustrating that normalizing both vector inputs of a dot product minimizes the probability of a single bit flip causing a large error in the dot product's result. Moreover, the absolute error is either less than one or very large, which allows detection of large errors. Then, we apply this to the GMRES iterative solver. We count all possible errors that can be introduced through faults in arithmetic in the computationally intensive orthogonalization phase of GMRES, and show that when the matrix is equilibrated, the absolute error is bounded above by one.

  13. Detachment Faulting & Geothermal Resources - Pearl Hot Spring, NV |

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

    Department of Energy Detachment Faulting & Geothermal Resources - Pearl Hot Spring, NV presentation at the April 2013 peer review meeting held in Denver, Colorado. pearl_hot_springs_peer2013.pdf (1.5 MB) More Documents & Publications Detachment Faulting & Geothermal Resources - Pearl Hot Spring, NV Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at Wister, CA Crump Geyser: High Precision Geophysics & Detailed Structural Exploration & Slim Well

  14. Near-surface geophysical characterization of Holocene faults conducive to

    Office of Scientific and Technical Information (OSTI)

    geothermal flow near Pyramid Lake, Nevada (Conference) | SciTech Connect Conference: Near-surface geophysical characterization of Holocene faults conducive to geothermal flow near Pyramid Lake, Nevada Citation Details In-Document Search Title: Near-surface geophysical characterization of Holocene faults conducive to geothermal flow near Pyramid Lake, Nevada Colton Dudley, Alison Dorsey, Paul Opdyke, Dustin Naphan, Marlon Ramos, John Louie, Paul Schwering, and Satish Pullammanappallil, 2013,

  15. Adding Fault Tolerance to NPB Benchmarks Using ULFM

    SciTech Connect (OSTI)

    Parchman, Zachary W; Vallee, Geoffroy R; Naughton III, Thomas J; Engelmann, Christian; Bernholdt, David E; Scott, Stephen L

    2016-01-01

    In the world of high-performance computing, fault tolerance and application resilience are becoming some of the primary concerns because of increasing hardware failures and memory corruptions. While the research community has been investigating various options, from system-level solutions to application-level solutions, standards such as the Message Passing Interface (MPI) are also starting to include such capabilities. The current proposal for MPI fault tolerant is centered around the User-Level Failure Mitigation (ULFM) concept, which provides means for fault detection and recovery of the MPI layer. This approach does not address application-level recovery, which is currently left to application developers. In this work, we present a mod- ification of some of the benchmarks of the NAS parallel benchmark (NPB) to include support of the ULFM capabilities as well as application-level strategies and mechanisms for application-level failure recovery. As such, we present: (i) an application-level library to checkpoint and restore data, (ii) extensions of NPB benchmarks for fault tolerance based on different strategies, (iii) a fault injection tool, and (iv) some preliminary results that show the impact of such fault tolerant strategies on the application execution.

  16. Microcomputer applications of, and modifications to, the modular fault trees

    SciTech Connect (OSTI)

    Zimmerman, T.L.; Graves, N.L.; Payne, A.C. Jr.; Whitehead, D.W.

    1994-10-01

    The LaSalle Probabilistic Risk Assessment was the first major application of the modular logic fault trees after the IREP program. In the process of performing the analysis, many errors were discovered in the fault tree modules that led to difficulties in combining the modules to form the final system fault trees. These errors are corrected in the revised modules listed in this report. In addition, the application of the modules in terms of editing them and forming them into the system fault trees was inefficient. Originally, the editing had to be done line by line and no error checking was performed by the computer. This led to many typos and other logic errors in the construction of the modular fault tree files. Two programs were written to help alleviate this problem: (1) MODEDIT - This program allows an operator to retrieve a file for editing, edit the file for the plant specific application, perform some general error checking while the file is being modified, and store the file for later use, and (2) INDEX - This program checks that the modules that are supposed to form one fault tree all link up appropriately before the files are,loaded onto the mainframe computer. Lastly, the modules were not designed for relay type logic common in BWR designs but for solid state type logic. Some additional modules were defined for modeling relay logic, and an explanation and example of their use are included in this report.

  17. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in...

  18. Remote Whispering Applying Time Reversal (Technical Report) ...

    Office of Scientific and Technical Information (OSTI)

    of spent nuclear fuel in storage casks without wires, or ... remote control of a system using sound). The time reversal process allows one to focus energy to a specific location ...

  19. Direct Imaging of Asymmetric Magnetization Reversal

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

    and H. Ohldag, "Direct imaging of asymmetric magnetization reversal in exchange-biased FeMnPd bilayers by x-ray photoemission electron microscopy," Phys. Rev. Lett. 94, 107203...

  20. Direct Imaging of Asymmetric Magnetization Reversal

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

    H. Ohldag, "Direct imaging of asymmetric magnetization reversal in exchange-biased FeMnPd bilayers by x-ray photoemission electron microscopy," Phys. Rev. Lett. 94, 107203 (2005...

  1. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Reversing the Circulation of Magnetic Vortices Print Wednesday, 31 July 2013 00:00 In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny

  2. Reversible Fuel Cells Workshop Summary Report

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

    Reversible Fuel Cells Workshop Summary Report Prepared for: U.S. Department of Energy Prepared by: Dr. Robert J. Remick National Renewable Energy Laboratory Mr. Douglas Wheeler DJW Technology YOU'RE INVITED  NREL WORKSHOP Reversible fuel cells operate like batteries and may be one solution to the problem of storing electricity generated by variable resources. This workshop will bring together subject matter experts and fuel cell developers to discuss the state-of- the-art and to draft a road

  3. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  4. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  5. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  6. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  7. Direct Imaging of Asymmetric Magnetization Reversal

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

    Direct Imaging of Asymmetric Magnetization Reversal Print The phenomenon of exchange bias has transformed how data is read on magnetic hard disks and created an explosion in their information storage density. However, it remains poorly understood, and even the fundamental mechanism of magnetic reversal for exchange-biased systems in changing magnetic fields is unclear. By using x-ray photoemission electron microscopy at the ALS to directly image the magnetic structure of an exchange-biased film,

  8. Photochromic Metal-Organic Frameworks: Reversible Control of...

    Office of Scientific and Technical Information (OSTI)

    Reversible Control of Singlet Oxygen Generation Citation Details In-Document Search Title: Photochromic Metal-Organic Frameworks: Reversible Control of Singlet Oxygen ...

  9. Reversible ratchet effects for vortices in conformal pinning...

    Office of Scientific and Technical Information (OSTI)

    Reversible ratchet effects for vortices in conformal pinning arrays Citation Details In-Document Search This content will become publicly available on May 3, 2016 Title: Reversible...

  10. Fractional Topological Phases and Broken Time-Reversal Symmetry...

    Office of Scientific and Technical Information (OSTI)

    Fractional Topological Phases and Broken Time-Reversal Symmetry in Strained Graphene Title: Fractional Topological Phases and Broken Time-Reversal Symmetry in Strained Graphene ...

  11. REVERSE RADIATIVE SHOCK LASER EXPERIMENTS RELEVANT TO ACCRETING...

    Office of Scientific and Technical Information (OSTI)

    REVERSE RADIATIVE SHOCK LASER EXPERIMENTS RELEVANT TO ACCRETING STREAM-DISK IMPACT IN INTERACTING BINARIES Citation Details In-Document Search Title: REVERSE RADIATIVE SHOCK LASER ...

  12. Time-reversal-invariant topological superconductivity in n -doped...

    Office of Scientific and Technical Information (OSTI)

    Time-reversal-invariant topological superconductivity in n -doped BiH Citation Details In-Document Search Title: Time-reversal-invariant topological superconductivity in n -doped ...

  13. Time-reversal symmetric hierarchy of fractional incompressible...

    Office of Scientific and Technical Information (OSTI)

    Time-reversal symmetric hierarchy of fractional incompressible liquids Title: Time-reversal symmetric hierarchy of fractional incompressible liquids Authors: Santos, Luiz ; ...

  14. Reversible Metal Hydride Thermal Energy Storage for High Temperature...

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

    Reversible Metal Hydride Thermal Energy Storage for High Temperature Power Generation Systems Reversible Metal Hydride Thermal Energy Storage for High Temperature Power Generation ...

  15. Factors affecting the recognition of faults exposed in exploratory trenches. Bulletin

    SciTech Connect (OSTI)

    Bonilla, M.G.; Lienkaemper, J.J.

    1991-01-01

    During excavation of the reactor shaft at the proposed Bodega Head nuclear reactor in California, a fault was found in the sediments overlying bedrock. This apparent lack of a complete connection with the bedrock fault led to disagreement as to whether the fault in the sediments was of tectonic or landslide origin. The report provides information on some of the conditions under which fault strands in trench walls are either difficult to see or die out, and the frequency of occurrence of these phenomena. Information is also provided on the widths of fault zones, on the deformation of the hanging wall and footwall of dip-slip faults, and on the frequency of occurrence of pebble rotation, open fissures, gouge, slickensides, mixing, fault breccia, fault rubble, crushing, polishing, water barriers, and liquefaction effects. Short summaries of information relating to fault strands that are poorly expressed or that die out have already been published (Bonilla and Lienkaemper, 1988, 1990).

  16. Field Guide for Testing Existing Photovoltaic Systems for Ground Faults and Installing Equipment to Mitigate Fire Hazards

    SciTech Connect (OSTI)

    Brooks, William; Basso, Thomas; Coddington, Michael

    2015-10-01

    Ground faults and arc faults are the two most common reasons for fires in photovoltaic (PV) arrays and methods exist that can mitigate the hazards. This report provides field procedures for testing PV arrays for ground faults, and for implementing high resolution ground fault and arc fault detectors in existing and new PV system designs.

  17. Accident Fault Trees for Defense Waste Processing Facility

    SciTech Connect (OSTI)

    Sarrack, A.G.

    1999-06-22

    The purpose of this report is to document fault tree analyses which have been completed for the Defense Waste Processing Facility (DWPF) safety analysis. Logic models for equipment failures and human error combinations that could lead to flammable gas explosions in various process tanks, or failure of critical support systems were developed for internal initiating events and for earthquakes. These fault trees provide frequency estimates for support systems failures and accidents that could lead to radioactive and hazardous chemical releases both on-site and off-site. Top event frequency results from these fault trees will be used in further APET analyses to calculate accident risk associated with DWPF facility operations. This report lists and explains important underlying assumptions, provides references for failure data sources, and briefly describes the fault tree method used. Specific commitments from DWPF to provide new procedural/administrative controls or system design changes are listed in the ''Facility Commitments'' section. The purpose of the ''Assumptions'' section is to clarify the basis for fault tree modeling, and is not necessarily a list of items required to be protected by Technical Safety Requirements (TSRs).

  18. Optimal design of reverse osmosis module networks

    SciTech Connect (OSTI)

    Maskan, F.; Wiley, D.E.; Johnston, L.P.M.; Clements, D.J.

    2000-05-01

    The structure of individual reverse osmosis modules, the configuration of the module network, and the operating conditions were optimized for seawater and brackish water desalination. The system model included simple mathematical equations to predict the performance of the reverse osmosis modules. The optimization problem was formulated as a constrained multivariable nonlinear optimization. The objective function was the annual profit for the system, consisting of the profit obtained from the permeate, capital cost for the process units, and operating costs associated with energy consumption and maintenance. Optimization of several dual-stage reverse osmosis systems were investigated and compared. It was found that optimal network designs are the ones that produce the most permeate. It may be possible to achieve economic improvements by refining current membrane module designs and their operating pressures.

  19. Time reversal signal processing for communication.

    SciTech Connect (OSTI)

    Young, Derek P.; Jacklin, Neil; Punnoose, Ratish J.; Counsil, David T.

    2011-09-01

    Time-reversal is a wave focusing technique that makes use of the reciprocity of wireless propagation channels. It works particularly well in a cluttered environment with associated multipath reflection. This technique uses the multipath in the environment to increase focusing ability. Time-reversal can also be used to null signals, either to reduce unintentional interference or to prevent eavesdropping. It does not require controlled geometric placement of the transmit antennas. Unlike existing techniques it can work without line-of-sight. We have explored the performance of time-reversal focusing in a variety of simulated environments. We have also developed new algorithms to simultaneously focus at a location while nulling at an eavesdropper location. We have experimentally verified these techniques in a realistic cluttered environment.

  20. Transport Physics in Reversed Shear Plasmas

    SciTech Connect (OSTI)

    Levinton, F.M.; Batha, S.H.; Beer, M.A.; Bell, M.G.; Budny, R.V.; Efthimion, P.C.; Mazzucato, E.; Nazikian, R.; Park, H.K.; Ramsey, A.T.; Schmidt, G.L.; Scott, S.D.; Synakowski, E.J.; Taylor, G.; Von Goeler, S.; Zarnstorff, M.C.; Bush, C.E.

    1997-12-31

    Reversed magnetic shear is considered a good candidate for improving the tokamak concept because it has the potential to stabilize MHD instabilities and reduce particle and energy transport. With reduced transport the high pressure gradient would generate a strong off-axis bootstrap current and could sustain a hollow current density profile. Such a combination of favorable conditions could lead to an attractive steady-state tokamak configuration. Indeed, a new tokamak confinement regime with reversed magnetic shear has been observed on the Tokamak Fusion Test Reactor (TFTR) where the particle, momentum, and ion thermal diffusivities drop precipitously, by over an order of magnitude. The particle diffusivity drops to the neoclassical level and the ion thermal diffusivity drops to much less than the neoclassical value in the region with reversed shear. This enhanced reversed shear (ERS) confinement mode is characterized by an abrupt transition with a large rate of rise of the density in the reversed shear region during neutral beam injection, resulting in nearly a factor of three increase in the central density to 1.2 X 10(exp 20) cube m. At the same time the density fluctuation level in the reversed shear region dramatically decreases. The ion and electron temperatures, which are about 20 keV and 7 keV respectively, change little during the ERS mode. The transport and transition into and out of the ERS mode have been studied on TFTR with plasma currents in the range 0.9-2.2 MA, with a toroidal magnetic field of 2.7-4.6 T, and the radius of the q(r) minimum, q{sub min}, has been varied from r/a = 0.35 to 0.55. Toroidal field and co/counter neutral beam injection toroidal rotation variations have been used to elucidate the underlying physics of the transition mechanism and power threshold of the ERS mode.

  1. Impact of Installation Faults on Heat Pump Performance

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

    Hourahan, Glenn; Baxter, Van D.

    2015-01-01

    Numerous studies and surveys indicate that typically-installed HVAC equipment operate inefficiently and waste considerable energy due to varied installation errors (faults) such as improper refrigerant charge, incorrect airflow, oversized equipment, and leaky ducts. This article summarizes the results of a large United States (U.S.) experimental/analytical study (U.S. contribution to IEA HPP Annex 36) of the impact that different faults have on the performance of an air-source heat pump (ASHP) in a typical U.S. single-family house. It combines building effects, equipment effects, and climate effects in an evaluation of the faults impact on seasonal energy consumption through simulations of the house/ASHPmore » pump system.« less

  2. Network resilience; A measure of network fault tolerance

    SciTech Connect (OSTI)

    Najjar, W. . Dept. of Computer Science); Gaudoit, J.L. . Dept. of Electrical Engineering)

    1990-02-01

    The failure of a node in a multicomputer system will not only reduce the computational power but also alter the network's topology. Network fault tolerance is a measure of the number of failures the network can sustain before a disconnection occurs. It is expressed traditionally as the network's node degree. In this paper, the authors propose a probabilistic measure of network fault tolerance expressed as the probability f a disconnection. Qualitative evaluation of this measure is presented. As expected, the single-node disconnection probability is the dominant factor irrespective of the topology under consideration. They derive an analytical approximation of the disconnection probability and verify it with Monte Carlo simulation. Based on this model, the measures of network resilience and relative network resilience are proposed as probabilistic measures of network fault tolerance. These are then used to evaluate the effects of the disconnection probability on the reliability of the system.

  3. Impact of Installation Faults on Heat Pump Performance

    SciTech Connect (OSTI)

    Hourahan, Glenn; Baxter, Van D.

    2015-01-01

    Numerous studies and surveys indicate that typically-installed HVAC equipment operate inefficiently and waste considerable energy due to varied installation errors (faults) such as improper refrigerant charge, incorrect airflow, oversized equipment, and leaky ducts. This article summarizes the results of a large United States (U.S.) experimental/analytical study (U.S. contribution to IEA HPP Annex 36) of the impact that different faults have on the performance of an air-source heat pump (ASHP) in a typical U.S. single-family house. It combines building effects, equipment effects, and climate effects in an evaluation of the faults impact on seasonal energy consumption through simulations of the house/ASHP pump system.

  4. Garbage collection: an exercise in distributed, fault-tolerant programming

    SciTech Connect (OSTI)

    Vestal, S.C.

    1987-01-01

    Two garbage-collection algorithms are presented to reclaim unused storage in object-oriented systems implemented on local area networks. The algorithms are fault-tolerant and allowed parallel, incremental collection in an object address space distributed throughout the system. The two approaches allow multiple collectors, so some unused storage can be reclaimed in partitioned networks. The first method makes use of fault-tolerant reference counts together with an algorithm to collect cycles of objects that would otherwise remain unclaimed. The second method adapts a parallel collector so that it can be used to collect subspaces of the entire network address space. Throughout this work concern is with a methodology for developing distributed, parallel, fault-tolerant programs. Also, there is concern with the suitability of object-oriented systems for such applications.

  5. Multistage network with an additional stage for fault tolerance

    SciTech Connect (OSTI)

    Adams, G.B. III; Siegel, H.J.

    1982-01-01

    The extra stage cube (ESC) network, a fault tolerant structure, is proposed for use in large-scale parallel and distributed supercomputer systems. This network is derived from the generalised cube network by the addition of one stage of interchange boxes and a bypass capability for two stages. It is shown that the ESC provides fault tolerance for any single failure. Further, the network can be controlled even when it has a single failure, using a simple modification of a routing tag scheme proposed for the generalised cube. Both one-to-one and broadcast connections under routing tag control are performable by the faulted ESC. The effects of the extra stage on the partitioning and permuting abilities of the network are described. 19 references.

  6. Observations on Faults and Associated Permeability Structures in Hydrogeologic Units at the Nevada Test Site

    SciTech Connect (OSTI)

    Prothro, Lance B.; Drellack, Sigmund L.; Haugstad, Dawn N.; Huckins-Gang, Heather E.; Townsend, Margaret J.

    2009-03-30

    Observational data on Nevada Test Site (NTS) faults were gathered from a variety of sources, including surface and tunnel exposures, core samples, geophysical logs, and down-hole cameras. These data show that NTS fault characteristics and fault zone permeability structures are similar to those of faults studied in other regions. Faults at the NTS form complex and heterogeneous fault zones with flow properties that vary in both space and time. Flow property variability within fault zones can be broken down into four major components that allow for the development of a simplified, first approximation model of NTS fault zones. This conceptual model can be used as a general guide during development and evaluation of groundwater flow and contaminate transport models at the NTS.

  7. Faulted reservoirs characterization by an image processing technique

    SciTech Connect (OSTI)

    Martinez-Angeles, R.

    1994-12-31

    This paper has developed an image processing method for obtaining the discontinuous areal distribution of oil parameters (formation top, porosity, water saturation,...) of faulted heterogeneous oil reservoirs. For its application it requires the previous knowledge of a set of discrete values z(k,l) from well-logs and seismic profiles. Faulted structures were discretized into continuous structures or blocks bounded by faults. The theoretical fundamental assumption of the proposed method establishes that the natural distributions can be considered as the superposition of several elementary brownian distributions, represented by discrete values z(k,l), whose physical model is the diffusion differential equation and its solution associated. This is a technique that allows the representation of a composed brownian distribution as a linear combination of all elementary brownian functions. For illustrating the operational aspect of brownian analysis, two examples are studied. The results are presented as a digital images by means of an image processing software. This method can be applied in mapping, three dimensions interpolation and reserves calculation of faulted reservoirs.

  8. Experimental and computational studies on stacking faults in zinc titanate

    SciTech Connect (OSTI)

    Sun, W.; Ageh, V.; Mohseni, H.; Scharf, T. W. E-mail: Jincheng.Du@unt.edu; Du, J. E-mail: Jincheng.Du@unt.edu

    2014-06-16

    Zinc titanate (ZnTiO{sub 3}) thin films grown by atomic layer deposition with ilmenite structure have recently been identified as an excellent solid lubricant, where low interfacial shear and friction are achieved due to intrafilm shear velocity accommodation in sliding contacts. In this Letter, high resolution transmission electron microscopy with electron diffraction revealed that extensive stacking faults are present on ZnTiO{sub 3} textured (104) planes. These growth stacking faults serve as a pathway for dislocations to glide parallel to the sliding direction and hence achieve low interfacial shear/friction. Generalized stacking fault energy plots also known as ?-surfaces were computed for the (104) surface of ZnTiO{sub 3} using energy minimization method with classical effective partial charge potential and verified by using density functional theory first principles calculations for stacking fault energies along certain directions. These two are in qualitative agreement but classical simulations generally overestimate the energies. In addition, the lowest energy path was determined to be along the [451{sup }] direction and the most favorable glide system is (104) ?451{sup }? that is responsible for the experimentally observed sliding-induced ductility.

  9. High voltage fault current limiter having immersed phase coils

    DOE Patents [OSTI]

    Darmann, Francis Anthony

    2014-04-22

    A fault current limiter including: a ferromagnetic circuit formed from a ferromagnetic material and including at least a first limb, and a second limb; a saturation mechanism surrounding a limb for magnetically saturating the ferromagnetic material; a phase coil wound around a second limb; a dielectric fluid surrounding the phase coil; a gaseous atmosphere surrounding the saturation mechanism.

  10. Reversing entanglement change by a weak measurement

    SciTech Connect (OSTI)

    Sun Qingqing; Zubairy, M. Suhail; Al-Amri, M.; Davidovich, Luiz

    2010-11-15

    Entanglement of a system changes due to interactions with the environment. A typical type of interaction is amplitude damping. If we add a detector to monitor the environment and only select the no-damping outcome, this amplitude damping is modified into a weak measurement. Here we show that the entanglement change of a two-qubit state due to amplitude damping or weak measurement can be probabilistically reversed. For the amplitude-damping case, the entanglement partially recovers under most conditions. For the weak-measurement case, the recovery of the initial entangled state is exact. The reversal procedure involves another weak measurement, preceded and followed by bit flips applied to both qubits. We propose a linear optics scheme for the experimental demonstration of these procedures.

  11. Forward and reverse characteristics of irradiated MOSFETs

    SciTech Connect (OSTI)

    Paccagnella, A.; Ceschia, M.; Verzellesi, G.; Dalla Betta, G.F.; Soncini, G.; Bellutti, P.; Fuochi, P.G.

    1996-06-01

    pMOSFETs biased with V{sub gs} < V{sub gd} during Co{sup 60} {gamma} irradiation have shown substantial differences between the forward and reverse subthreshold characteristics, induced by a non-uniform charge distribution in the gate oxide. Correspondingly, modest differences have been observed in the over-threshold I-V characteristics. After irradiation, the forward subthreshold curves can shift at higher or lower gate voltages than the reverse ones. The former behavior has been observed in long-channel devices, in agreement with the classical MOS theory and numerical simulations. The latter result has been obtained in short-channel devices, and it has been correlated to a parasitic punch-through conduction mechanism.

  12. On the design of reversible QDCA systems.

    SciTech Connect (OSTI)

    DeBenedictis, Erik P.; Frank, Michael P. (Florida State University, Tallahassee, FL); Ottavi, Marco; Frost-Murphy, Sarah E.

    2006-10-01

    This work is the first to describe how to go about designing a reversible QDCA system. The design space is substantial, and there are many questions that a designer needs to answer before beginning to design. This document begins to explicate the tradeoffs and assumptions that need to be made and offers a range of approaches as starting points and examples. This design guide is an effective tool for aiding designers in creating the best quality QDCA implementation for a system.

  13. Membranes for Reverse-Organic Air Separations

    Broader source: Energy.gov [DOE]

    New Membranes Use Reverse Separation to Reduce Pollutant Emissions: Many industrial applications need a process to separate pollutants known as volatile organic compounds (VOCs) from air in order to protect the environment and save energy. One such application is the venting of vapor from underground storage tanks (UST) used in gasoline storage and dispensing. These vapors, which can build up and create high pressure within the UST, contribute to ground-level ozone and smog upon release.

  14. Reversible Sigma C-C Bond Formation Between Phenanthroline Ligands...

    Office of Scientific and Technical Information (OSTI)

    Reversible Sigma C-C Bond Formation Between Phenanthroline Ligands Activated by (C5Me5)2Yb Citation Details In-Document Search Title: Reversible Sigma C-C Bond Formation Between ...

  15. Development of Asset Fault Signatures for Prognostic and Health Management in the Nuclear Industry

    SciTech Connect (OSTI)

    Vivek Agarwal; Nancy J. Lybeck; Randall Bickford; Richard Rusaw

    2014-06-01

    Proactive online monitoring in the nuclear industry is being explored using the Electric Power Research Institute’s Fleet-Wide Prognostic and Health Management (FW-PHM) Suite software. The FW-PHM Suite is a set of web-based diagnostic and prognostic tools and databases that serves as an integrated health monitoring architecture. The FW-PHM Suite has four main modules: Diagnostic Advisor, Asset Fault Signature (AFS) Database, Remaining Useful Life Advisor, and Remaining Useful Life Database. This paper focuses on development of asset fault signatures to assess the health status of generator step-up generators and emergency diesel generators in nuclear power plants. Asset fault signatures describe the distinctive features based on technical examinations that can be used to detect a specific fault type. At the most basic level, fault signatures are comprised of an asset type, a fault type, and a set of one or more fault features (symptoms) that are indicative of the specified fault. The AFS Database is populated with asset fault signatures via a content development exercise that is based on the results of intensive technical research and on the knowledge and experience of technical experts. The developed fault signatures capture this knowledge and implement it in a standardized approach, thereby streamlining the diagnostic and prognostic process. This will support the automation of proactive online monitoring techniques in nuclear power plants to diagnose incipient faults, perform proactive maintenance, and estimate the remaining useful life of assets.

  16. Characterization of Quaternary and suspected Quaternary faults, regional studies, Nevada and California

    SciTech Connect (OSTI)

    Anderson, R.E.; Bucknam, R.C.; Crone, A.J.; Haller, K.M.; Machette, M.N.; Personius, S.F.; Barnhard, T.P.; Cecil, M.J.; Dart, R.L.

    1995-12-31

    This report presents the results of geologic studies that help define the Quaternary history of selected faults in the region around Yucca Mountain, Nevada. These results are relevant to the seismic-design basis of a potential nuclear waste repository at Yucca Mountain. The relevancy is based, in part, on a need for additional geologic data that became apparent in ongoing studies that resulted in the identification of 51 relevant and potentially relevant individual and compound faults and fault zones in the 100-km-radius region around the Yucca Mountain site. Geologic data used to characterize the regional faults and fault zones as relevant or potentially relevant seismic sources includes age and displacement information, maximum fault lengths, and minimum distances between the fault and the Yucca Mountain site. For many of the regional faults, no paleoseismic field studies have previously been conducted, and age and displacement data are sparse to nonexistent. In November 1994, the Branch of Earthquake and Landslide Hazards entered into two Memoranda of Agreement with the Yucca Mountain Project Branch to conduct field reconnaissance, analysis, and interpretation of six relevant and six potentially relevant regional faults. This report describes the results of study of those faults exclusive of those in the Pahrump-Stewart Valley-Ash Meadows-Amargosa Valley areas. We also include results of a cursory study of faults on the west flank of the Specter Range and in the northern part of the Last Chance Range. A four-phase strategy was implemented for the field study.

  17. High resolution, shallow seismic reflection survey of the Pen Branch fault

    SciTech Connect (OSTI)

    Stieve, A.

    1991-05-15

    The purpose of this project, at the Savannah River River Site (SRS) was to acquire, process, and interpret 28 km (17.4 miles) of high resolution seismic reflection data taken across the trace of the Pen Branch fault and other suspected, intersecting north-south trending faults. The survey was optimized for the upper 300 ft of geologic strata in order to demonstrate the existence of very shallow, flat lying horizons, and to determine the depth of the fault or to sediments deformed by the fault. Field acquisition and processing parameters were selected to define small scale spatial variability and structural features in the vicinity of the Pen Branch fault leading to the definition and the location of the Pen Branch fault, the shallowest extent of the fault, and the quantification of the sense and magnitude of motion. Associated geophysical, borehole, and geologic data were incorporated into the investigation to assist in the determination of optimal parameters and aid in the interpretation.

  18. Progress on the Development of Reversible SOFC Stack Technology

    Broader source: Energy.gov [DOE]

    Presentation by Casey Brown, Versa Power Systems, at the NREL Reversible Fuel Cells Workshop, April 19, 2011

  19. Development of Reversible Fuel Cell Systems at Proton Energy

    Broader source: Energy.gov [DOE]

    Presentation by Everett Anderson, PROTON ON SITE, at the NREL Reversible Fuel Cells Workshop, April 19, 2011

  20. Time Reversal in Solids (Linear and Nonlinear Elasticity): Multimedia Resources in Time Reversal

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

    Dynamic nonlinear elastic behavior, nonequilibrium dynamics, first observed as a curiosity in earth materials has now been observed in a great variety of solids. The primary manifestations of the behavior are characteristic wave distortion, and slow dynamics, a recovery process to equilibrium that takes place linearly with the logarithm of time, over hours to days after a wave disturbance. The link between the diverse materials that exhibit nonequilibrium dynamics appears to be the presence of soft regions, thought to be 'damage' at many scales, ranging from order 10-9 m to 10-1 m at least. The regions of soft matter may be distributed as in a rock sample, or isolated, as in a sample with a single crack [LANLhttp://www.lanl.gov/orgs/ees/ees11/geophysics/nonlinear/nonlinear.shtml]. The Geophysics Group (EES-11) at Los Alamos National Laboratory has posted two or more multimedia items under each of the titles below to demonstrate aspects of their work: 1) Source Reconstruction Using Time Reversal; 2) Robustness and Efficiency of Time Reversal Acoustics in Solid Media; 3) Audio Example of Time Reversal - Speech Privacy; 4) Crack Imagining with Time Reversal - Experimental Results; 5) Time Reversal of the 2004 (M9.0) Sumatra Earthquake.

  1. Rule based decision support system for single-line fault detection in a delta-delta connected distribution system

    SciTech Connect (OSTI)

    Momoh, J.A.; Dias, L.G.; Thor, T. . Dept. of Electrical Engineering); Laird, D. )

    1994-05-01

    Single-line fault detection, faulted feeder identification, fault type classification, fault location and fault impedance estimation, continue to pose a problem to delta-delta connected distribution systems such as the Los Angeles Department of Water and Power (LADWP) which has over 1,500 feeder circuits at the 4.8kV voltage level. This paper describes a rule based decision support (RBDS) system application to single-line fault detection in a delta-delta connected distribution system. The RBDS system is built from knowledge acquired through exhaustive simulation based on non-arcing type fault situations. It is primarily designed to detect the presence of a fault, identify the faulted feeder, the faulted phase and classify the fault type. It is also designed to gauge the proximity of the fault to the substation and to assess the fault impedance. A fault in the distribution system, upon identification, triggers an alarm with explanatory facility leading to the fault. The RBDS system was tested with different sets of simulated data and proved successful in most cases. Additional tests will be done using field data made available by LADWP. The RBDS system module is a prototype integrated fault detection scheme to be installed in a LADWP distribution substation.

  2. When did movement begin on the Furnace Creek fault zone

    SciTech Connect (OSTI)

    Reheis, M. )

    1993-04-01

    About 50 km of post-Jurassic right-lateral slip has occurred on the northern part of the Furnace Creek fault zone (FCFZ). The sedimentology, stratigraphy, and structure of Tertiary rocks suggest that movement on the fault began no earlier than 12--8 Ma and possibly as late as 5--4 Ma. Large remnants of erosion surfaces occur on both sides of the FCFZ in the southern White Mountains and Fish Lake Valley and are buried by rhyolite and basalt, mostly 12--10 Ma; the ash flows and welded tuffs were likely erupted from sources at least 40 km to the east. Thus, the area probably had gentle topography, suggesting a lengthy period of pre-late Miocene tectonic stability. On the west side of the FCFZ, Cambrian sedimentary rocks are buried by a fanglomerate with an [sup [minus

  3. Testing of 3-meter Prototype Fault Current Limiting Cables

    SciTech Connect (OSTI)

    Gouge, Michael J; Duckworth, Robert C; Demko, Jonathan A; Rey, Christopher M; Thompson, James R; Lindsay, David T; Tolbert, Jerry Carlton; Willen, Dag; Lentge, Heidi; Thidemann, Carsten; Carter, Bill

    2009-01-01

    Two 3-m long, single-phase cables have been fabricated by Ultera from second generation (2G) superconductor supplied by American Superconductor. The first cable was made with two layers of 2G tape conductor and had a critical current of 5,750 A while the second cable had four layers and a critical current of 8,500 A. AC loss was measured for both cables at ac currents of up to 4 kArms. Ultera performed initial fault current studies of both cables in Denmark with limited currents in the range from 9.1 to 44 kA. Results from these tests will provide a basis for a 25-m long, three-phase, prototype cable to be tested at ORNL early next year and a 300-m long, fault current limiting, superconducting cable to be installed in a ConEd substation in New York City.

  4. NREL Research Proves Wind Can Provide Ancillary Grid Fault Response |

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

    Energy Systems Integration | NREL NREL Research Proves Wind Can Provide Ancillary Grid Fault Response April 1, 2016 Interior of the controllable grid interface test facility, showing a long hallway and shelves full of electronic equipment. The controllable grid interface test facility at the National Wind Technology Center makes it possible to research the effectiveness of wind energy in providing ancillary grid services such as frequency control. Photo by Dennis Schroeder/NREL 27442 Image

  5. Superconducting fault current-limiter with variable shunt impedance

    DOE Patents [OSTI]

    Llambes, Juan Carlos H; Xiong, Xuming

    2013-11-19

    A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

  6. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  7. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  8. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  9. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  10. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  11. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  12. Reversing the Circulation of Magnetic Vortices

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

    Reversing the Circulation of Magnetic Vortices Print In magnetic media, information is stored in binary form-one or zero, depending on which way the electronic spins are aligned in a given section of the medium. Recently, however, magnetic vortices have drawn scientists toward a new possibility: multibit storage in which each logic unit has four states instead of two and can store twice the information. Each tiny magnetic whirl has a polarity that can point up or down and a circulation that can

  13. Kinetic Stability of the Field Reversed Configuration

    SciTech Connect (OSTI)

    E.V. Belova; R.C. Davidson; H. Ji; and M. Yamada

    2002-07-09

    New computational results are presented which advance the understanding of the stability properties of the Field-Reversed Configuration (FRC). The FRC is an innovative confinement approach that offers a unique fusion reactor potential because of its compact and simple geometry, translation properties, and high plasma beta. One of the most important issues is FRC stability with respect to low-n (toroidal mode number) MHD modes. There is a clear discrepancy between the predictions of standard MHD theory that many modes should be unstable on the MHD time scale, and the observed macroscopic resilience of FRCs in experiments.

  14. Modeling of fault activation and seismicity by injection directly into a fault zone associated with hydraulic fracturing of shale-gas reservoirs

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

    Rutqvist, Jonny; Rinaldi, Antonio P.; Cappa, Frédéric; Moridis, George J.

    2015-03-01

    We conducted three-dimensional coupled fluid-flow and geomechanical modeling of fault activation and seismicity associated with hydraulic fracturing stimulation of a shale-gas reservoir. We simulated a case in which a horizontal injection well intersects a steeply dip- ping fault, with hydraulic fracturing channeled within the fault, during a 3-hour hydraulic fracturing stage. Consistent with field observations, the simulation results show that shale-gas hydraulic fracturing along faults does not likely induce seismic events that could be felt on the ground surface, but rather results in numerous small microseismic events, as well as aseismic deformations along with the fracture propagation. The calculated seismicmore » moment magnitudes ranged from about -2.0 to 0.5, except for one case assuming a very brittle fault with low residual shear strength, for which the magnitude was 2.3, an event that would likely go unnoticed or might be barely felt by humans at its epicenter. The calculated moment magnitudes showed a dependency on injection depth and fault dip. We attribute such dependency to variation in shear stress on the fault plane and associated variation in stress drop upon reactivation. Our simulations showed that at the end of the 3-hour injection, the rupture zone associated with tensile and shear failure extended to a maximum radius of about 200 m from the injection well. The results of this modeling study for steeply dipping faults at 1000 to 2500 m depth is in agreement with earlier studies and field observations showing that it is very unlikely that activation of a fault by shale-gas hydraulic fracturing at great depth (thousands of meters) could cause felt seismicity or create a new flow path (through fault rupture) that could reach shallow groundwater resources.« less

  15. Modeling of fault activation and seismicity by injection directly into a fault zone associated with hydraulic fracturing of shale-gas reservoirs

    SciTech Connect (OSTI)

    Rutqvist, Jonny; Rinaldi, Antonio P.; Cappa, Frédéric; Moridis, George J.

    2015-03-01

    We conducted three-dimensional coupled fluid-flow and geomechanical modeling of fault activation and seismicity associated with hydraulic fracturing stimulation of a shale-gas reservoir. We simulated a case in which a horizontal injection well intersects a steeply dip- ping fault, with hydraulic fracturing channeled within the fault, during a 3-hour hydraulic fracturing stage. Consistent with field observations, the simulation results show that shale-gas hydraulic fracturing along faults does not likely induce seismic events that could be felt on the ground surface, but rather results in numerous small microseismic events, as well as aseismic deformations along with the fracture propagation. The calculated seismic moment magnitudes ranged from about -2.0 to 0.5, except for one case assuming a very brittle fault with low residual shear strength, for which the magnitude was 2.3, an event that would likely go unnoticed or might be barely felt by humans at its epicenter. The calculated moment magnitudes showed a dependency on injection depth and fault dip. We attribute such dependency to variation in shear stress on the fault plane and associated variation in stress drop upon reactivation. Our simulations showed that at the end of the 3-hour injection, the rupture zone associated with tensile and shear failure extended to a maximum radius of about 200 m from the injection well. The results of this modeling study for steeply dipping faults at 1000 to 2500 m depth is in agreement with earlier studies and field observations showing that it is very unlikely that activation of a fault by shale-gas hydraulic fracturing at great depth (thousands of meters) could cause felt seismicity or create a new flow path (through fault rupture) that could reach shallow groundwater resources.

  16. Review of field-reversed configurations

    SciTech Connect (OSTI)

    Steinhauer, Loren C.

    2011-07-15

    This review addresses field-reversed configurations (FRCs), which are compact-toroidal magnetic systems with little or no toroidal field and very high {beta} (ratio of plasma pressure to magnetic pressure). Although enthusiasm for the FRC has primarily been driven by its potential for an attractive fusion reactor, this review focuses on the physics rather than on technological or engineering aspects. Major advances in both theory and experiment have taken place since the previous comprehensive FRC review in 1988. Even so many questions remain. In particular, even though FRC experiments have exhibited remarkable stability, how well this extrapolates to larger systems remains unresolved. The review considers FRCs under familiar topical categories: equilibrium, global stability, self-organization, transport, formation, and sustainment.

  17. Digital reverse propagation in focusing Kerr media

    SciTech Connect (OSTI)

    Goy, Alexandre; Psaltis, Demetri

    2011-03-15

    Lenses allow the formation of clear images in homogeneous linear media. Holography is an alternative imaging method, but its use is limited to cases in which it provides an advantage, such as three-dimensional imaging. In nonlinear media, lenses no longer work. The light produces intensity-dependent aberrations. The reverse propagation method used in digital holography to form images from recorded holograms works even in Kerr media [M. Tsang, D. Psaltis, and F. G. Omenetto, Opt. Lett. 28, 1873 (2003).]. The principle has been experimentally demonstrated recently in defocusing media [C. Barsi, W.Wan, and J.W. Fleischer, Nat. Photonics 3, 211 (2009).]. Here, we report experimental results in focusing media.

  18. Significance of recurrent fault movement at Grays Point quarry, southeast Missouri

    SciTech Connect (OSTI)

    Diehl, S.F.; Throckmorton, C.K. ); Clendenin, C.W. )

    1993-03-01

    Geologic relationships indicate recurrent movement on a fault exposed at Grays Point, MO. Faulting offsets Middle-Late Ordovician Plattin Group, Decorah Group, Kimmswick Limestone, and Maquoketa Group strata. In plan, the fault is characterized by a relatively narrow zone (30--70 m) of northeast-striking fault slices associated with a northwest-striking zone of right-stepping en echelon fractures. This systematic fracture-fault array identifies right-lateral strike-slip movement. A vertically offset basal Decorah Group contact shows 22 m of down-to-the-southeast dip slip, which indicates a component of oblique slip. Oldest recognizable movement on the fault is evidenced by Maquoketa Group strata that fill a northeast-striking, wedge-shaped synform. Post-Ordovician movement along an adjacent subvertical fault displaces part of this synform 300 m right laterally. In thin section, the northwest-striking fracture set shows a polyphase history of deformation indicated by cataclastic textures and intrusion of carbonate-rich fluids. Three periods of movement occurred: (1) initial fracturing sealed by authigenic mineral cements; (2) renewed fracturing associated with recrystallization of sub-rounded clasts; and (3) subsequent brecciation marked by angular clasts and filling of fractures and vugs. Each successive fluid intrusion is characterized by an increase in grain size of the authigenic cement. The fault is subparallel to the regional, northeast-striking English Hill fault system. Polyphase oblique-slip deformation suggests that the fault, like others in southeastern Missouri, is a reactivated Late Proterozoic-Cambrian zone of weakness. Initial fault reactivation occurred during Middle-Late Ordovician as opposed to Devonian, as commonly interpreted for southeast Missouri. Multiple authigenic mineral cements imply that fluids may have been an important factor influencing the fault's tendency to be reactivated.

  19. Arc-Fault Detector Algorithm Evaluation Method Utilizing Prerecorded Arcing Signatures

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

    Arc-Fault Detector Algorithm Evaluation Method Utilizing Prerecorded Arcing Signatures Jay Johnson 1 and Jack Kang 2 1 Sandia National Laboratories, Albuquerque, NM, USA 2 Sensata Technologies, Attleboro, MA, USA ABSTRACT Abstract - The 2011 National Electrical Code® Article 690.11 requires photovoltaic systems on or penetrating a building to include a DC arc-fault protection device. In order to satisfy this requirement, new Arc-Fault Detectors (AFDs) are being developed by multiple

  20. NEAR-SURFACE GEOPHYSICAL CHARACTERIZATION OF A HOLOCENE FAULT CONDUCIVE TO

    Office of Scientific and Technical Information (OSTI)

    GEOTHERMAL FLOW NEAR PYRAMID LAKE, NEVADA (Other) | SciTech Connect NEAR-SURFACE GEOPHYSICAL CHARACTERIZATION OF A HOLOCENE FAULT CONDUCIVE TO GEOTHERMAL FLOW NEAR PYRAMID LAKE, NEVADA Citation Details In-Document Search Title: NEAR-SURFACE GEOPHYSICAL CHARACTERIZATION OF A HOLOCENE FAULT CONDUCIVE TO GEOTHERMAL FLOW NEAR PYRAMID LAKE, NEVADA Linear deposits of calcium carbonate tufa columns mark recent faults that cut 11 ka Lake Lahontan sediments at Astor Pass, north of Pyramid Lake,

  1. Non-abelian fractional quantum hall effect for fault-resistant...

    Office of Scientific and Technical Information (OSTI)

    Non-abelian fractional quantum hall effect for fault-resistant topological quantum computation. Citation Details In-Document Search Title: Non-abelian fractional quantum hall...

  2. Sandia Research on PV Arc-Fault Detection Submitted for US Patent

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

    Predictive Simulation of Engines Transportation Energy Consortiums Engine Combustion ... The 2011 National Electrical Code requires PV DC series arc-fault protection, but does ...

  3. Pull-Apart in Strike-Slip Fault Zone | Open Energy Information

    Open Energy Info (EERE)

    of sinistral fault systems, resulting in localized crustal extension and enhanced permeability. Other definitions:Wikipedia Reegle Controlling Structures List of controlling...

  4. Wind Power Plant Enhancement with a Fault-Current Limiter: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Gevorgian, V.; DeLaRosa, F.

    2011-03-01

    This paper investigates the capability of a saturable core fault-current limiter to limit the short circuit current of different types of wind turbine generators.

  5. VOLTTRON Compatible Whole-Building Root-Fault Detection and Diagnosis...

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

    tool that integrates both statistical process control and machine learning techniques and rule-based methods to achieve a whole-building energy system "root-fault" diagnosis. ...

  6. Stepover or Relay Ramp in Normal Fault Zones | Open Energy Information

    Open Energy Info (EERE)

    intersections between the overlapping fault strands results in increased fracture density that enhances hydrothermal fluid flow. Other definitions:Wikipedia Reegle Controlling...

  7. A Fault Oblivious Extreme-Scale Execution Environment

    SciTech Connect (OSTI)

    McKie, Jim

    2014-11-20

    The FOX project, funded under the ASCR X-stack I program, developed systems software and runtime libraries for a new approach to the data and work distribution for massively parallel, fault oblivious application execution. Our work was motivated by the premise that exascale computing systems will provide a thousand-fold increase in parallelism and a proportional increase in failure rate relative to today’s machines. To deliver the capability of exascale hardware, the systems software must provide the infrastructure to support existing applications while simultaneously enabling efficient execution of new programming models that naturally express dynamic, adaptive, irregular computation; coupled simulations; and massive data analysis in a highly unreliable hardware environment with billions of threads of execution. Our OS research has prototyped new methods to provide efficient resource sharing, synchronization, and protection in a many-core compute node. We have experimented with alternative task/dataflow programming models and shown scalability in some cases to hundreds of thousands of cores. Much of our software is in active development through open source projects. Concepts from FOX are being pursued in next generation exascale operating systems. Our OS work focused on adaptive, application tailored OS services optimized for multi → many core processors. We developed a new operating system NIX that supports role-based allocation of cores to processes which was released to open source. We contributed to the IBM FusedOS project, which promoted the concept of latency-optimized and throughput-optimized cores. We built a task queue library based on distributed, fault tolerant key-value store and identified scaling issues. A second fault tolerant task parallel library was developed, based on the Linda tuple space model, that used low level interconnect primitives for optimized communication. We designed fault tolerance mechanisms for task parallel computations

  8. Field Guide for Testing Existing Photovoltaic Systems for Ground Faults and Installing Equipment to Mitigate Fire Hazards: November 2012 - October 2013

    SciTech Connect (OSTI)

    Brooks, William

    2015-02-01

    Ground faults and arc faults are the two most common reasons for fires in photovoltaic (PV) arrays and methods exist that can mitigate the hazards. This report provides field procedures for testing PV arrays for ground faults, and for implementing high resolution ground fault and arc fault detectors in existing and new PV system designs.

  9. Photochromic Metal-Organic Frameworks: Reversible Control of...

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

    Photochromic Metal-Organic Frameworks: Reversible Control of Singlet Oxygen Generation Previous Next List Jihye Park, Dawei Feng, Shuai Yuan and Hong-Cai Zhou, Angew. Chem. Int....

  10. A Reversible Crystallinity-Preserving Phase Transition in Metal...

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

    Reversible Crystallinity-Preserving Phase Transition in Metal-Organic Frameworks: Discovery, ... was discovered in a metal-organic framework (MOF) PCN-526. During the phase ...

  11. Reversible Alteration of CO2 Adsorption upon Photochemical or...

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

    Reversible Alteration of CO2 Adsorption upon Photochemical or Thermal Treatment in a Metal-Organic Framework Previous Next List Jinhee Park , Daqiang Yuan , Khanh T. Pham , ...

  12. Reversible Seeding in Storage Rings (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    We propose to generate steady-state microbunching in a storage ring with a reversible seeding scheme. High gain harmonic generation (HGHG) and echo-enabled harmonic generation ...

  13. A Reversible Crystallinity-Preserving Phase Transition in Metal...

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

    Reversible Crystallinity-Preserving Phase Transition in Metal-Organic Frameworks: Discovery, Mechanistic Studies, and Potential Applications Previous Next List Liu, Dahuan; Liu,...

  14. Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC...

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

    Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Presented ...

  15. Materials and System Issues with Reversible SOFC | Department...

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

    Cells Workshop Summary Report Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Lessons Learned from SOFCSOEC Development...

  16. Dynamics and efficiency of magnetic vortex circulation reversal...

    Office of Scientific and Technical Information (OSTI)

    Dynamics and efficiency of magnetic vortex circulation reversal Not Available Temp HTML Storage 2: Urbnek, Michal; Uhl, Vojtch; Lambert, Charles-Henri; Kan, Jimmy J.; ...

  17. Reversible Aptamer-Au Plasmon Rulers for Secreted Single Molecules

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

    Lee, Somin Eunice; Chen, Qian; Bhat, Ramray; Petkiewicz, Shayne; Smith, Jessica M.; Ferry, Vivian E.; Correia, Ana Luisa; Alivisatos, A. Paul; Bissell, Mina J.

    2015-06-03

    Plasmon rulers, consisting of pairs of gold nanoparticles, allow single-molecule analysis without photobleaching or blinking; however, current plasmon rulers are irreversible, restricting detection to only single events. Here, we present a reversible plasmon ruler, comprised of coupled gold nanoparticles linked by a single aptamer, capable of binding individual secreted molecules with high specificity. We show that the binding of target secreted molecules to the reversible plasmon ruler is characterized by single-molecule sensitivity, high specificity, and reversibility. Lastly, such reversible plasmon rulers should enable dynamic and adaptive live-cell measurement of secreted single molecules in their local microenvironment.

  18. Development of Hydrologic Characterization Technology of Fault Zones -- Phase I, 2nd Report

    SciTech Connect (OSTI)

    Karasaki, Kenzi; Onishi, Tiemi; Black, Bill; Biraud, Sebastien

    2009-03-31

    This is the year-end report of the 2nd year of the NUMO-LBNL collaborative project: Development of Hydrologic Characterization Technology of Fault Zones under NUMO-DOE/LBNL collaboration agreement, the task description of which can be found in the Appendix 3. Literature survey of published information on the relationship between geologic and hydrologic characteristics of faults was conducted. The survey concluded that it may be possible to classify faults by indicators based on various geometric and geologic attributes that may indirectly relate to the hydrologic property of faults. Analysis of existing information on the Wildcat Fault and its surrounding geology was performed. The Wildcat Fault is thought to be a strike-slip fault with a thrust component that runs along the eastern boundary of the Lawrence Berkeley National Laboratory. It is believed to be part of the Hayward Fault system but is considered inactive. Three trenches were excavated at carefully selected locations mainly based on the information from the past investigative work inside the LBNL property. At least one fault was encountered in all three trenches. Detailed trench mapping was conducted by CRIEPI (Central Research Institute for Electric Power Industries) and LBNL scientists. Some intriguing and puzzling discoveries were made that may contradict with the published work in the past. Predictions are made regarding the hydrologic property of the Wildcat Fault based on the analysis of fault structure. Preliminary conceptual models of the Wildcat Fault were proposed. The Wildcat Fault appears to have multiple splays and some low angled faults may be part of the flower structure. In parallel, surface geophysical investigations were conducted using electrical resistivity survey and seismic reflection profiling along three lines on the north and south of the LBNL site. Because of the steep terrain, it was difficult to find optimum locations for survey lines as it is desirable for them to be as

  19. Coordinated Fault-Tolerance for High-Performance Computing Final Project Report

    SciTech Connect (OSTI)

    Panda, Dhabaleswar Kumar; Beckman, Pete

    2011-07-28

    With the Coordinated Infrastructure for Fault Tolerance Systems (CIFTS, as the original project came to be called) project, our aim has been to understand and tackle the following broad research questions, the answers to which will help the HEC community analyze and shape the direction of research in the field of fault tolerance and resiliency on future high-end leadership systems. Will availability of global fault information, obtained by fault information exchange between the different HEC software on a system, allow individual system software to better detect, diagnose, and adaptively respond to faults? If fault-awareness is raised throughout the system through fault information exchange, is it possible to get all system software working together to provide a more comprehensive end-to-end fault management on the system? #15; What are the missing fault-tolerance features that widely used HEC system software lacks today that would inhibit such software from taking advantage of systemwide global fault information? #15; What are the practical limitations of a systemwide approach for end-to-end fault management based on fault awareness and coordination? #15; What mechanisms, tools, and technologies are needed to bring about fault awareness and coordination of responses on a leadership-class system? #15; What standards, outreach, and community interaction are needed for adoption of the concept of fault awareness and coordination for fault management on future systems? Keeping our overall objectives in mind, the CIFTS team has taken a parallel fourfold approach. #15; Our central goal was to design and implement a light-weight, scalable infrastructure with a simple, standardized interface to allow communication of fault-related information through the system and facilitate coordinated responses. This work led to the development of the Fault Tolerance Backplane (FTB) publish-subscribe API specification, together with a reference implementation and several experimental

  20. Award ER25750: Coordinated Infrastructure for Fault Tolerance Systems Indiana University Final Report

    SciTech Connect (OSTI)

    Lumsdaine, Andrew

    2013-03-08

    The main purpose of the Coordinated Infrastructure for Fault Tolerance in Systems initiative has been to conduct research with a goal of providing end-to-end fault tolerance on a systemwide basis for applications and other system software. While fault tolerance has been an integral part of most high-performance computing (HPC) system software developed over the past decade, it has been treated mostly as a collection of isolated stovepipes. Visibility and response to faults has typically been limited to the particular hardware and software subsystems in which they are initially observed. Little fault information is shared across subsystems, allowing little flexibility or control on a system-wide basis, making it practically impossible to provide cohesive end-to-end fault tolerance in support of scientific applications. As an example, consider faults such as communication link failures that can be seen by a network library but are not directly visible to the job scheduler, or consider faults related to node failures that can be detected by system monitoring software but are not inherently visible to the resource manager. If information about such faults could be shared by the network libraries or monitoring software, then other system software, such as a resource manager or job scheduler, could ensure that failed nodes or failed network links were excluded from further job allocations and that further diagnosis could be performed. As a founding member and one of the lead developers of the Open MPI project, our efforts over the course of this project have been focused on making Open MPI more robust to failures by supporting various fault tolerance techniques, and using fault information exchange and coordination between MPI and the HPC system software stack from the application, numeric libraries, and programming language runtime to other common system components such as jobs schedulers, resource managers, and monitoring tools.

  1. Mobility and coalescence of stacking fault tetrahedra in Cu

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

    Martínez, Enrique; Uberuaga, Blas P.

    2015-03-13

    Stacking fault tetrahedra (SFTs) are ubiquitous defects in face-centered cubic metals. They are produced during cold work plastic deformation, quenching experiments or under irradiation. From a dislocation point of view, the SFTs are comprised of a set of stair-rod dislocations at the (110) edges of a tetrahedron bounding triangular stacking faults. These defects are extremely stable, increasing their energetic stability as they grow in size. At the sizes visible within transmission electron microscope they appear nearly immobile. Contrary to common belief, we show in this report, using a combination of molecular dynamics and temperature accelerated dynamics, how small SFTs canmore » diffuse by temporarily disrupting their structure through activated thermal events. More over, we demonstrate that the diffusivity of defective SFTs is several orders of magnitude higher than perfect SFTs, and can be even higher than isolated vacancies. Finally, we show how SFTs can coalesce, forming a larger defect in what is a new mechanism for the growth of these omnipresent defects.« less

  2. Editorial: Mathematical Methods and Modeling in Machine Fault Diagnosis

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

    Yan, Ruqiang; Chen, Xuefeng; Li, Weihua; Sheng, Shuangwen

    2014-12-18

    Modern mathematics has commonly been utilized as an effective tool to model mechanical equipment so that their dynamic characteristics can be studied analytically. This will help identify potential failures of mechanical equipment by observing change in the equipment’s dynamic parameters. On the other hand, dynamic signals are also important and provide reliable information about the equipment’s working status. Modern mathematics has also provided us with a systematic way to design and implement various signal processing methods, which are used to analyze these dynamic signals, and to enhance intrinsic signal components that are directly related to machine failures. This special issuemore » is aimed at stimulating not only new insights on mathematical methods for modeling but also recently developed signal processing methods, such as sparse decomposition with potential applications in machine fault diagnosis. Finally, the papers included in this special issue provide a glimpse into some of the research and applications in the field of machine fault diagnosis through applications of the modern mathematical methods.« less

  3. Restoration and testing of an HTS fault current controller

    SciTech Connect (OSTI)

    Waynert, J. A.; Boenig, H.; Mielke, C. H.; Willis, J. O.; Burley, B. L.

    2002-01-01

    A three-phase, 1200 A, 12.5 kV fault current controller using three HTS 4 mH coils, was built by industry and tested in 1999 at the Center Substation of Southern California Edison in Norwalk, CA. During the testing, it appeared that each of the three single-phase units had experienced a voltage breakdown, one externally and two internally. Los Alamos National Laboratory (LANL) was asked by DOE to restore the operation of the fault current controller provided the HTS coils had not been damaged during the initial substation tests. When the internally-failed coil vacuum vessels were opened it became evident that in these two vessels, a flashover had occurred at the high voltage bus section leading to the terminals of the superconducting coil. An investigation into the failure mechanism resulted in six possible causes for the flashover. Based on these causes, the high voltage bus was completely redesigned. Single-phase tests were successfully performed on the modified unit at a 13.7 kV LANL substation. This paper presents the postulated voltage flashover failure mechanisms, the new high voltage bus design which mitigates the failure mechanisms, the sequence of tests used to validate the new design, and finally, the results of variable load and short-circuit tests with the single-phase unit operating on the LANL 13.7 kV substation.

  4. Editorial: Mathematical Methods and Modeling in Machine Fault Diagnosis

    SciTech Connect (OSTI)

    Yan, Ruqiang; Chen, Xuefeng; Li, Weihua; Sheng, Shuangwen

    2014-12-18

    Modern mathematics has commonly been utilized as an effective tool to model mechanical equipment so that their dynamic characteristics can be studied analytically. This will help identify potential failures of mechanical equipment by observing change in the equipment’s dynamic parameters. On the other hand, dynamic signals are also important and provide reliable information about the equipment’s working status. Modern mathematics has also provided us with a systematic way to design and implement various signal processing methods, which are used to analyze these dynamic signals, and to enhance intrinsic signal components that are directly related to machine failures. This special issue is aimed at stimulating not only new insights on mathematical methods for modeling but also recently developed signal processing methods, such as sparse decomposition with potential applications in machine fault diagnosis. Finally, the papers included in this special issue provide a glimpse into some of the research and applications in the field of machine fault diagnosis through applications of the modern mathematical methods.

  5. Unconventional modelling of faulted reservoirs: a case study

    SciTech Connect (OSTI)

    Goldthorpe, W.H.; Chow, Y.S.

    1985-02-01

    An example is presented of detailed unconventional gridding of the North Rankin Field, which is a large, structurally complex gas-condensate field offshore Western Australia. A non-Cartesian areal grid was used with corner point geometry to approximate a generalized curvilinear coordinate system for the surface and interior of each reservoir unit. Coordinate lines in the vertical plane at any node in the grid were tilted where necessary to define sloping edges and sides of grid blocks. Thus, any sloping twisted surface could be modelled. To investigate possible communication across faults between different geological units, transmissibilities at faults were automatically calculated for any over-lapping cells and sensitivities made of the effect of varying these transmissibilities on well production, recovery factors, pressure decline and water encroachment. The model was solved with a fully implicit simulator using a Newton-Raphson iteration method for the non-linear equations and a variant of the Conjugate Gradient procedure with a preconditioning matrix for the linear equations.

  6. Pipeline coating impedance effects on powerline fault current coupling

    SciTech Connect (OSTI)

    Dabkowski, J.

    1989-12-01

    Prior research leading to the development of predictive electromagnetic coupling computer codes has shown that the coating conductance is the principal factor in determining the response of a pipeline to magnetic induction from an overhead power transmission line. Under power line fault conditions, a high voltage may stress the coating causing a significant change in its conductance, and hence, the coupling response. Based upon laboratory experimentation and analysis, a model has been developed which allows prediction of the modified coating characteristics when subjected to high voltage during fault situations. Another program objective was the investigation of a method to determine the high voltage behavior of an existing coating from low voltage in situ field measurements. Such a method appeared conceptually feasible for non-porous coatings whose conductance is primarily a result of current leakage through existing holidays. However, limited testing has shown that difficulties in determining the steel-electrolyte capacitance limit the application of the method Methods for field measurement of the pipeline coating conductance were also studied for both dc ad ac signal excitation. Ac techniques offer the advantage that cathodic protection current interruption is not required, thus eliminating depolarization effects. However, ac field measurement techniques need additional refinement before these methods can be generally applied. 53 figs.

  7. Fault current limiter and alternating current circuit breaker

    DOE Patents [OSTI]

    Boenig, Heinrich J.

    1998-01-01

    A solid-state circuit breaker and current limiter for a load served by an alternating current source having a source impedance, the solid-state circuit breaker and current limiter comprising a thyristor bridge interposed between the alternating current source and the load, the thyristor bridge having four thyristor legs and four nodes, with a first node connected to the alternating current source, and a second node connected to the load. A coil is connected from a third node to a fourth node, the coil having an impedance of a value calculated to limit the current flowing therethrough to a predetermined value. Control means are connected to the thyristor legs for limiting the alternating current flow to the load under fault conditions to a predetermined level, and for gating the thyristor bridge under fault conditions to quickly reduce alternating current flowing therethrough to zero and thereafter to maintain the thyristor bridge in an electrically open condition preventing the alternating current from flowing therethrough for a predetermined period of time.

  8. Fault current limiter and alternating current circuit breaker

    DOE Patents [OSTI]

    Boenig, H.J.

    1998-03-10

    A solid-state circuit breaker and current limiter are disclosed for a load served by an alternating current source having a source impedance, the solid-state circuit breaker and current limiter comprising a thyristor bridge interposed between the alternating current source and the load, the thyristor bridge having four thyristor legs and four nodes, with a first node connected to the alternating current source, and a second node connected to the load. A coil is connected from a third node to a fourth node, the coil having an impedance of a value calculated to limit the current flowing therethrough to a predetermined value. Control means are connected to the thyristor legs for limiting the alternating current flow to the load under fault conditions to a predetermined level, and for gating the thyristor bridge under fault conditions to quickly reduce alternating current flowing therethrough to zero and thereafter to maintain the thyristor bridge in an electrically open condition preventing the alternating current from flowing therethrough for a predetermined period of time. 9 figs.

  9. A high performance field-reversed configuration

    SciTech Connect (OSTI)

    Binderbauer, M. W.; Tajima, T.; Steinhauer, L. C.; Garate, E.; Tuszewski, M.; Smirnov, A.; Gota, H.; Barnes, D.; Deng, B. H.; Thompson, M. C.; Trask, E.; Yang, X.; Putvinski, S.; Rostoker, N.; Andow, R.; Aefsky, S.; Bolte, N.; Bui, D. Q.; Ceccherini, F.; Clary, R.; and others

    2015-05-15

    Conventional field-reversed configurations (FRCs), high-beta, prolate compact toroids embedded in poloidal magnetic fields, face notable stability and confinement concerns. These can be ameliorated by various control techniques, such as introducing a significant fast ion population. Indeed, adding neutral beam injection into the FRC over the past half-decade has contributed to striking improvements in confinement and stability. Further, the addition of electrically biased plasma guns at the ends, magnetic end plugs, and advanced surface conditioning led to dramatic reductions in turbulence-driven losses and greatly improved stability. Together, these enabled the build-up of a well-confined and dominant fast-ion population. Under such conditions, highly reproducible, macroscopically stable hot FRCs (with total plasma temperature of ∼1 keV) with record lifetimes were achieved. These accomplishments point to the prospect of advanced, beam-driven FRCs as an intriguing path toward fusion reactors. This paper reviews key results and presents context for further interpretation.

  10. Rigid-rotor, field-reversed configuration

    SciTech Connect (OSTI)

    Conti, F. Giammanco, F.; Plasma Diagnostics and Technologies Ltd., Via Giuntini 63, 56023 Navacchio ; Wessel, F. J.; Binderbauer, M. W.; Bolte, N.; Morehouse, M.; Qerushi, A.; Rahman, H. U.; Roche, T.; Slepchenkov, M.

    2014-02-15

    The radial profiles, n(r), B{sub z}(r), and E{sub r}(r), for a Flux-Coil (“inductively driven”), Field-Reversed Configuration (FC-FRC) are measured and compared to the predictions of the Rigid-Rotor Model (RRM), which is an analytic, one-dimensional, time-independent, equilibrium description for the FRC. Injectors mounted on both ends of the confinement vessel provide a pre-fill plasma. Coaxial coils mounted outside the vacuum boundaries of the annular-confinement vessel accelerate the plasma and produce the FRC. The density profile is measured by laser interferometry, the magnetic-field profile using an in-situ probe array, and the electric-field profile using an in-situ, floating-probe array. Free parameters for each profile are measured, which also allow other intrinsic-plasma parameters to be determined, using computer-fit algorithms: null radius, radial thickness, plasma temperature, rotation frequencies, the latter of which are independently verified by spectroscopy. All radial profiles agree with the RRM predictions, for the experimental configuration, parameter regime, and specified-time interval studied here.

  11. Reversible piezomagnetoelectric switching in bulk polycrystalline ceramics

    SciTech Connect (OSTI)

    Stevenson, T. Bennett, J.; Brown, A. P.; Wines, T.; Bell, A. J.; Comyn, T. P.; Smith, R. I.

    2014-08-01

    Magnetoelectric (ME) coupling in materials offer tremendous advantages in device functionality enabling technologies including advanced electronic memory, combining electronic speed, and efficiency with magnetic robustness. However, low cost polycrystalline ME materials are excluded from most commercial applications, operating only at cryogenic temperatures, impractically large electric/magnetic fields, or with low ME coefficients (1-100 mV/cm Oe). Despite this, the technological potential of single compound ME coupling has continued to drive research into multiferroics over the last two decades. Here we show that by manipulating the large induced atomic strain within the polycrystalline, room temperature multiferroic compound 0.7BiFeO{sub 3}–0.3PbTiO{sub 3}, we can induce a reversible, piezoelectric strain controlled ME effect. Employing an in situ neutron diffraction experiment, we have demonstrated that this piezomagnetoelectric effect manifests with an applied electric field >8 kV/mm at the onset of piezoelectric strain, engineered in to the compound by crystallographic phase mixing. This produces a remarkable intrinsic ME coefficient of 1276 mV/cm Oe, due to a strain driven modification to the oxygen sub-lattice, inducing an increase in magnetic moment per Fe{sup 3+} ion of +0.142 μ{sub B}. This work provides a framework for investigations into strain engineered nanostructures to realize low-cost ME devices designed from the atoms up, as well as contributing to the deeper understanding of single phase ME coupling mechanisms.

  12. Liquid suspensions of reversible metal hydrides

    DOE Patents [OSTI]

    Reilly, J.J.; Grohse, E.W.; Winsche, W.E.

    1983-12-08

    The reversibility of the process M + x/2 H/sub 2/ ..-->.. MH/sub x/, where M is a metal hydride former that forms a hydride MH/sub x/ in the presence of H/sub 2/, generally used to store and recall H/sub 2/, is found to proceed under a liquid, thereby to reduce contamination, provide better temperature control and provide in situ mobility of the reactants. Thus, a slurry of particles of a metal hydride former with an inert solvent is subjected to temperature and pressure controlled atmosphere containing H/sub 2/, to store hydrogen (at high pressures) and to release (at low pressures) previously stored hydrogen. The direction of the flow of the H/sub 2/ through the liquid is dependent upon the H/sub 2/ pressure in the gas phase at a given temperature. When the former is above the equilibrium absorption pressure of the respective hydride the reaction proceeds to the right, i.e., the metal hydride is formed and hydrogen is stored in the solid particle. When the H/sub 2/ pressure in the gas phase is below the equilibrium dissociation pressure of the respective hydride the reaction proceeds to the left, the metal hydride is decomposed and hydrogen is released into the gas phase.

  13. Influence of Transcontinental arch on Cretaceous listric-normal faulting, west flank, Denver basin

    SciTech Connect (OSTI)

    Davis, T.L.

    1983-08-01

    Seismic studies along the west flank of the Denver basin near Boulder and Greeley, Colorado illustrate the interrelationship between shallow listric-normal faulting in the Cretaceous and deeper basement-controlled faulting. Deeper fault systems, primarily associated with the Transcontinental arch, control the styles and causative mechanisms of listric-normal faulting that developed in the Cretaceous. Three major stratigraphic levels of listric-normal faulting occur in the Boulder-Greeley area. These tectonic sensitive intervals are present in the following Cretaceous formations: Laramie-Fox Hills-upper Pierre, middle Pierre Hygiene zone, and the Niobrara-Carlile-Greenhorn. Documentation of the listric-normal fault style reveals a Wattenberg high, a horst block or positive feature of the greater Transcontinental arch, was active in the east Boulder-Greeley area during Cretaceous time. Paleotectonic events associated with the Wattenberg high are traced through analysis of the listric-normal fault systems that occur in the area. These styles are important to recognize because of their stratigraphic and structural influence on Cretaceous petroleum reservoir systems in the Denver basin. Similar styles of listric-normal faulting occur in the Cretaceous in many Rocky Mountain foreland basins.

  14. Effect of faulting on ground-water movement in the Death Valley region, Nevada and California

    SciTech Connect (OSTI)

    Faunt, C.C.

    1997-12-31

    This study characterizes the hydrogeologic system of the Death Valley region, an area covering approximately 100,000 square kilometers. The study also characterizes the effects of faults on ground-water movement in the Death Valley region by synthesizing crustal stress, fracture mechanics,a nd structural geologic data. The geologic conditions are typical of the Basin and Range Province; a variety of sedimentary and igneous intrusive and extrusive rocks have been subjected to both compressional and extensional deformation. Faulting and associated fracturing is pervasive and greatly affects ground-water flow patterns. Faults may become preferred conduits or barriers to flow depending on whether they are in relative tension, compression, or shear and other factors such as the degree of dislocations of geologic units caused by faulting, the rock types involved, the fault zone materials, and the depth below the surface. The current crustal stress field was combined with fault orientations to predict potential effects of faults on the regional ground-water flow regime. Numerous examples of fault-controlled ground-water flow exist within the study area. Hydrologic data provided an independent method for checking some of the assumptions concerning preferential flow paths. 97 refs., 20 figs., 5 tabs.

  15. System for detecting and limiting electrical ground faults within electrical devices

    DOE Patents [OSTI]

    Gaubatz, Donald C.

    1990-01-01

    An electrical ground fault detection and limitation system for employment with a nuclear reactor utilizing a liquid metal coolant. Elongate electromagnetic pumps submerged within the liquid metal coolant and electrical support equipment experiencing an insulation breakdown occasion the development of electrical ground fault current. Without some form of detection and control, these currents may build to damaging power levels to expose the pump drive components to liquid metal coolant such as sodium with resultant undesirable secondary effects. Such electrical ground fault currents are detected and controlled through the employment of an isolated power input to the pumps and with the use of a ground fault control conductor providing a direct return path from the affected components to the power source. By incorporating a resistance arrangement with the ground fault control conductor, the amount of fault current permitted to flow may be regulated to the extent that the reactor may remain in operation until maintenance may be performed, notwithstanding the existence of the fault. Monitors such as synchronous demodulators may be employed to identify and evaluate fault currents for each phase of a polyphase power, and control input to the submerged pump and associated support equipment.

  16. The role of the digital fault recorder in the automated substation

    SciTech Connect (OSTI)

    Brandt, J.D.

    1996-10-01

    This paper addresses the role of the digital fault recorder in the automated substation. The topics of the paper include distributed architecture, the substation LAN and reduced installation costs, multiple functions, improved substation intelligence, record generation and record merging, fault summaries, master station software, and future considerations.

  17. Reversibly immobilized biological materials in monolayer films on electrodes

    DOE Patents [OSTI]

    Weaver, Paul F. (Golden, CO); Frank, Arthur J. (Lakewood, CO)

    1993-01-01

    Methods and techniques are described for reversibly binding charged biological particles in a fluid medium to an electrode surface. The methods are useful in a variety of applications. The biological materials may include microbes, proteins, and viruses. The electrode surface may consist of reversibly electroactive materials such as polyvinylferrocene, silicon-linked ferrocene or quinone.

  18. Reducing current reversal time in electric motor control

    DOE Patents [OSTI]

    Bredemann, Michael V

    2014-11-04

    The time required to reverse current flow in an electric motor is reduced by exploiting inductive current that persists in the motor when power is temporarily removed. Energy associated with this inductive current is used to initiate reverse current flow in the motor.

  19. Reversibly immobilized biological materials in monolayer films on electrodes

    DOE Patents [OSTI]

    Weaver, P.F.; Frank, A.J.

    1993-05-04

    Methods and techniques are described for reversibly binding charged biological particles in a fluid medium to an electrode surface. The methods are useful in a variety of applications. The biological materials may include microbes, proteins, and viruses. The electrode surface may consist of reversibly electroactive materials such as polyvinylferrocene, silicon-linked ferrocene or quinone.

  20. Method for distinguishing multiple targets using time-reversal acoustics

    DOE Patents [OSTI]

    Berryman, James G.

    2004-06-29

    A method for distinguishing multiple targets using time-reversal acoustics. Time-reversal acoustics uses an iterative process to determine the optimum signal for locating a strongly reflecting target in a cluttered environment. An acoustic array sends a signal into a medium, and then receives the returned/reflected signal. This returned/reflected signal is then time-reversed and sent back into the medium again, and again, until the signal being sent and received is no longer changing. At that point, the array has isolated the largest eigenvalue/eigenvector combination and has effectively determined the location of a single target in the medium (the one that is most strongly reflecting). After the largest eigenvalue/eigenvector combination has been determined, to determine the location of other targets, instead of sending back the same signals, the method sends back these time reversed signals, but half of them will also be reversed in sign. There are various possibilities for choosing which half to do sign reversal. The most obvious choice is to reverse every other one in a linear array, or as in a checkerboard pattern in 2D. Then, a new send/receive, send-time reversed/receive iteration can proceed. Often, the first iteration in this sequence will be close to the desired signal from a second target. In some cases, orthogonalization procedures must be implemented to assure the returned signals are in fact orthogonal to the first eigenvector found.

  1. System and method for motor fault detection using stator current noise cancellation

    DOE Patents [OSTI]

    Zhou, Wei; Lu, Bin; Nowak, Michael P.; Dimino, Steven A.

    2010-12-07

    A system and method for detecting incipient mechanical motor faults by way of current noise cancellation is disclosed. The system includes a controller configured to detect indicia of incipient mechanical motor faults. The controller further includes a processor programmed to receive a baseline set of current data from an operating motor and define a noise component in the baseline set of current data. The processor is also programmed to acquire at least on additional set of real-time operating current data from the motor during operation, redefine the noise component present in each additional set of real-time operating current data, and remove the noise component from the operating current data in real-time to isolate any fault components present in the operating current data. The processor is then programmed to generate a fault index for the operating current data based on any isolated fault components.

  2. A Framework For Evaluating Comprehensive Fault Resilience Mechanisms In Numerical Programs

    SciTech Connect (OSTI)

    Chen, S.; Peng, L.; Bronevetsky, G.

    2015-01-09

    As HPC systems approach Exascale, their circuit feature will shrink, while their overall size will grow, all at a fixed power limit. These trends imply that soft faults in electronic circuits will become an increasingly significant problem for applications that run on these systems, causing them to occasionally crash or worse, silently return incorrect results. This is motivating extensive work on application resilience to such faults, ranging from generic techniques such as replication or checkpoint/restart to algorithm-specific error detection and resilience techniques. Effective use of such techniques requires a detailed understanding of (1) which vulnerable parts of the application are most worth protecting (2) the performance and resilience impact of fault resilience mechanisms on the application. This paper presents FaultTelescope, a tool that combines these two and generates actionable insights by presenting in an intuitive way application vulnerabilities and impact of fault resilience mechanisms on applications.

  3. System and method for bearing fault detection using stator current noise cancellation

    DOE Patents [OSTI]

    Zhou, Wei; Lu, Bin; Habetler, Thomas G.; Harley, Ronald G.; Theisen, Peter J.

    2010-08-17

    A system and method for detecting incipient mechanical motor faults by way of current noise cancellation is disclosed. The system includes a controller configured to detect indicia of incipient mechanical motor faults. The controller further includes a processor programmed to receive a baseline set of current data from an operating motor and define a noise component in the baseline set of current data. The processor is also programmed to repeatedly receive real-time operating current data from the operating motor and remove the noise component from the operating current data in real-time to isolate any fault components present in the operating current data. The processor is then programmed to generate a fault index for the operating current data based on any isolated fault components.

  4. A comparison of ROChem reverse osmosis and spiral wound reverse osmosis membrane modules

    SciTech Connect (OSTI)

    Siler, J.L.

    1992-01-31

    Testing of the ROChem Disc Tube[reg sign] reverse osmosis (RO) module's performance on biologically active feed waters has been completed. Both the ROChem module (using Filmtec standard-rejection seawater membranes) and the Filmtec spiral-wound membrane module (using Filmtec high-rejection seawater membranes) were tested with stimulant solutions containing typical bacteria and metal hydroxide levels found in the F/H Effluent Treatment Facility (ETF) influent. Results indicate that the ROChem module gave superior performance over the spiral-wound module. Water flux losses were reduced by over 30% for water recoveries above 40%.

  5. A comparison of ROChem reverse osmosis and spiral wound reverse osmosis membrane modules

    SciTech Connect (OSTI)

    Siler, J.L.

    1992-01-31

    Testing of the ROChem Disc Tube{reg_sign} reverse osmosis (RO) module`s performance on biologically active feed waters has been completed. Both the ROChem module (using Filmtec standard-rejection seawater membranes) and the Filmtec spiral-wound membrane module (using Filmtec high-rejection seawater membranes) were tested with stimulant solutions containing typical bacteria and metal hydroxide levels found in the F/H Effluent Treatment Facility (ETF) influent. Results indicate that the ROChem module gave superior performance over the spiral-wound module. Water flux losses were reduced by over 30% for water recoveries above 40%.

  6. Buffered coscheduling for parallel programming and enhanced fault tolerance

    DOE Patents [OSTI]

    Petrini, Fabrizio; Feng, Wu-chun

    2006-01-31

    A computer implemented method schedules processor jobs on a network of parallel machine processors or distributed system processors. Control information communications generated by each process performed by each processor during a defined time interval is accumulated in buffers, where adjacent time intervals are separated by strobe intervals for a global exchange of control information. A global exchange of the control information communications at the end of each defined time interval is performed during an intervening strobe interval so that each processor is informed by all of the other processors of the number of incoming jobs to be received by each processor in a subsequent time interval. The buffered coscheduling method of this invention also enhances the fault tolerance of a network of parallel machine processors or distributed system processors

  7. Characterization and application of microearthquake clusters to problems of scaling, fault zone dynamics, and seismic monitoring at Parkfield, California

    SciTech Connect (OSTI)

    Nadeau, R.M.

    1995-10-01

    This document contains information about the characterization and application of microearthquake clusters and fault zone dynamics. Topics discussed include: Seismological studies; fault-zone dynamics; periodic recurrence; scaling of microearthquakes to large earthquakes; implications of fault mechanics and seismic hazards; and wave propagation and temporal changes.

  8. Magnetization reversal in TmCrO{sub 3}

    SciTech Connect (OSTI)

    Yoshii, Kenji

    2012-11-15

    Highlights: ► We observed two magnetization reversals in TmCrO{sub 3}. ► The reversal at 28 K is attributed to antiparallel coupling between Cr{sup 3+} and Tm{sup 3+}. ► The other reversal originates from spin reorientation. ► Magnetocaloric effect is observed at the spin reorientation temperature. ► Characteristic magnetization switching is demonstrated. -- Abstract: The perovskite chromite TmCrO{sub 3} shows magnetization reversal at two temperatures. The reversal at ∼28 K is attributed to the antiparallel coupling between Tm{sup 3+} and Cr{sup 3+} moments, while that at the lower temperature (∼6–7 K) is rooted in a rotation of the magnetic moments. Magnetocaloric measurements offer a relatively large entropy change (∼4–5 J kg{sup −1} K{sup −1}) at the lower temperature. The reversal at ∼28 K is accompanied by a sign change of an exchange-bias-like field. The absence of the training effect suggests that this behavior is rooted in unidirectional magnetic anisotropy. The existence of the two magnetization reversals offers the characteristic switching of magnetization. For example, the magnetization is flipped without changing the direction of the applied magnetic field.

  9. Three-dimensional time reversal communications in elastic media

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

    Anderson, Brian E.; Ulrich, Timothy J.; Le Bas, Pierre-Yves; Ten Cate, James A.

    2016-02-23

    Our letter presents a series of vibrational communication experiments, using time reversal, conducted on a set of cast iron pipes. Time reversal has been used to provide robust, private, and clean communications in many underwater acoustic applications. Also, the use of time reversal to communicate along sections of pipes and through a wall is demonstrated here in order to overcome the complications of dispersion and multiple scattering. These demonstrations utilize a single source transducer and a single sensor, a triaxial accelerometer, enabling multiple channels of simultaneous communication streams to a single location.

  10. Investigation of Ground-Fault Protection Devices for Photovoltaic Power Systems Applications

    SciTech Connect (OSTI)

    BOWER,WARD I.; WILES,JOHN

    2000-10-03

    Photovoltaic (PV) power systems, like other electrical systems, may be subject to unexpected ground faults. Installed PV systems always have invisible elements other than those indicated by their electrical schematics. Stray inductance, capacitance and resistance are distributed throughout the system. Leakage currents associated with the PV modules, the interconnected array, wires, surge protection devices and conduit add up and can become large enough to look like a ground-fault. PV systems are frequently connected to other sources of power or energy storage such as batteries, standby generators, and the utility grid. This complex arrangement of distributed power and energy sources, distributed impedance and proximity to other sources of power requires sensing of ground faults and proper reaction by the ground-fault protection devices. The different dc grounding requirements (country to country) often add more confusion to the situation. This paper discusses the ground-fault issues associated with both the dc and ac side of PV systems and presents test results and operational impacts of backfeeding commercially available ac ground-fault protection devices under various modes of operation. Further, the measured effects of backfeeding the tripped ground-fault devices for periods of time comparable to anti-islanding allowances for utility interconnection of PV inverters in the United States are reported.

  11. Pattern of extensional faulting in pelagic carbonates of the Unbria-Marche Apennines of central Italy

    SciTech Connect (OSTI)

    Alvarez, W. )

    1990-05-01

    The Umbria-Marche Apennines provide a new region in which the nature passive-margin extensional faulting can be studied in outcrop. In these dominantly pelagic carbonate rocks of Jurassic and Cretaceous age, horsts acted as shallow, nonvolcani seamounts, while tilted half grabens formed deeper basins. One well-exposed seamount-basin transition agrees in general with the model of listric normal faulting and tilted half grabens, but shows interesting and significant divergences when studied in detail. A small sedimentary wedge at the faulted margin of a horst-block seamount thickens unexpectedly toward the adjacent basin. This wedge developed because of local convex-upward curvature of the shallowest part of a fault which at depth must have concave-up, listric geometry. The local sedimentary wedge resulted from deposition on the hanging wall as it tilted, followed by differential compaction of younger limestones that lapped onto the gentle slope leading from the horst-block seamount toward the basin. The map pattern of listric normal faulting in the Umbria-Marche Apennines suggests that both principal strain axes were extensional, in contrast to the usual pattern of listric faults crossed by transfer faults.

  12. Recurrent motion on Precambrian-age basement faults, Palo Duro basin, Texas Panhandle

    SciTech Connect (OSTI)

    Budnik, R.T.

    1983-03-01

    The distribution of Late Precambrian through Quaternary strata in the Palo Duro basin and surrounding uplifts documents recurrent motion on Precambrian-age basement faults. Basement blocks have been uplifted with little tilting or folding of overlying strata along a system of northwest-southeast oriented faults, part of a regional trend extending from central Colorado to southwestern Oklahoma. The orientation of basement terranes in Colorado and that of a 50-mi (80-km) long mylonite zone in east-central New Mexico suggest a Precambrian age for the faults. An Arkosic sandstone overlies basement and underlies a Cambrian(.) quartzose sandstone in a few Palo Duro basin wells. It may represent debris shed from active fault blocks during the opening of the southern Oklahoma aulocogen in the Late Precambrian or Early Cambrian. Ordovician carbonates thin or are missing beneath Mississippian carbonates on some fault blocks, indicating a post-Ordovician-pre-Mississippian period of faulting. The greatest amount of deformation occurred during the Pennsylvanian. Thickness, distribution, and facies of sediments were controlled by the location of active faults. Lower Pennsylvanian strata thin by up to 50% across some structures. Fault blocks provided sources of arkosic debris and loci for carbonate buildups throughout the Pennsylvanian and Early Permian. Around the periphery of the basin, Late Pennsylvanian or Early Permian faulting caused a wedging out of older units beneath the Wolfcamp. Permian, Triassic, and Neogene units, along with present topography, all have been subtly affected by basement structures. The entire section thins over basement highs. Middle and Upper Permian evaporites are thicker in structural lows. The overlying Dockum Group (Triassic) and Ogallala Formation (Neogene), both nonmarine clastic units, become finer grained over basement highs. Present topographic highs coincide with some basement highs.

  13. A practical approach to accurate fault location on extra high voltage teed feeders

    SciTech Connect (OSTI)

    Aggarwal, R.K.; Coury, D.V.; Johns, A.T. . School of Electronic and Electrical Engineering); Kalam, A. )

    1993-07-01

    This paper describes the basis of an alternative approach for accurately locating faults on teed feeders and the technique developed utilizes fault voltages and currents at all three ends. The method is virtually independent of fault resistance and largely insensitive to variations in source impedance, teed and line configurations, including line untransposition. The paper presents the basic theory of the technique which is then extensively tested using simulated primary system voltage and current waveforms which in turn include the transducer/hardware errors encountered in practice. The performance clearly shows a high degree of accuracy attained.

  14. Method and system for controlling a permanent magnet machine during fault conditions

    DOE Patents [OSTI]

    Krefta, Ronald John; Walters, James E.; Gunawan, Fani S.

    2004-05-25

    Method and system for controlling a permanent magnet machine driven by an inverter is provided. The method allows for monitoring a signal indicative of a fault condition. The method further allows for generating during the fault condition a respective signal configured to maintain a field weakening current even though electrical power from an energy source is absent during said fault condition. The level of the maintained field-weakening current enables the machine to operate in a safe mode so that the inverter is protected from excess voltage.

  15. Reversible CO Scavenging via Adsorbate-Dependent Spin State Transition...

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

    Reversible CO Scavenging via Adsorbate-Dependent Spin State Transitions in an Iron(II)-Triazolate Metal-Organic Framework Previous Next List Reed, Douglas A.; Xiao, Dianne J.; ...

  16. The TITAN reversed-field-pinch fusion reactor study

    SciTech Connect (OSTI)

    Not Available

    1990-01-01

    This paper on titan plasma engineering contains papers on the following topics: reversed-field pinch as a fusion reactor; parametric systems studies; magnetics; burning-plasma simulations; plasma transient operations; current drive; and physics issues for compact RFP reactors.

  17. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    millitesla (mT) to reverse the direction of a vortex core. ... and their possible application to data storage technologies. ... Is there a physical limit to how far this process can go? At ...

  18. Effects of q -profile structures on intrinsic torque reversals...

    Office of Scientific and Technical Information (OSTI)

    Title: Effects of q -profile structures on intrinsic torque reversals Authors: Lu, Z. X. ; Wang, W. X. ; Diamond, P. H. ; Tynan, G. ; Ethier, S. ; Chen, J. ; Gao, C. ; Rice, J. E. ...

  19. Reversible Magnesium Intercalation into a Layered Oxyfluoride Cathode -

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

    Joint Center for Energy Storage Research December 18, 2015, Research Highlights Reversible Magnesium Intercalation into a Layered Oxyfluoride Cathode Powder diffraction of oxyfluoridecathode with intercalated Mg and capacities of oxyfluorideand oxide cathodes Scientific Achievement Magnesium was reversibly intercalated at room temperature into an oxyfluoride cathode without the co-intercalation of electrolytes or protons and without the formation of unwanted side-products that commonly

  20. A Fault-Oblivious Extreme-Scale Execution Environment (FOX)

    SciTech Connect (OSTI)

    Van Hensbergen, Eric; Speight, William; Xenidis, Jimi

    2013-03-15

    IBM Research’s contribution to the Fault Oblivious Extreme-scale Execution Environment (FOX) revolved around three core research deliverables: ● collaboration with Boston University around the Kittyhawk cloud infrastructure which both enabled a development and deployment platform for the project team and provided a fault-injection testbed to evaluate prototypes ● operating systems research focused on exploring role-based operating system technologies through collaboration with Sandia National Labs on the NIX research operating system and collaboration with the broader IBM Research community around a hybrid operating system model which became known as FusedOS ● IBM Research also participated in an advisory capacity with the Boston University SESA project, the core of which was derived from the K42 operating system research project funded in part by DARPA’s HPCS program. Both of these contributions were built on a foundation of previous operating systems research funding by the Department of Energy’s FastOS Program. Through the course of the X-stack funding we were able to develop prototypes, deploy them on production clusters at scale, and make them available to other researchers. As newer hardware, in the form of BlueGene/Q, came online, we were able to port the prototypes to the new hardware and release the source code for the resulting prototypes as open source to the community. In addition to the open source coded for the Kittyhawk and NIX prototypes, we were able to bring the BlueGene/Q Linux patches up to a more recent kernel and contribute them for inclusion by the broader Linux community. The lasting impact of the IBM Research work on FOX can be seen in its effect on the shift of IBM’s approach to HPC operating systems from Linux and Compute Node Kernels to role-based approaches as prototyped by the NIX and FusedOS work. This impact can be seen beyond IBM in follow-on ideas being incorporated into the proposals for the Exasacale Operating

  1. An artificial neutral network fault-diagnostic adviser for a nuclear power plant with error prediction

    SciTech Connect (OSTI)

    Kim, Keehoon

    1992-12-31

    This thesis is part of an ongoing project at Iowa State University to develop ANN bases fault diagnostic systems to detect and classify operational transients at nuclear power plants.

  2. An artificial neutral network fault-diagnostic adviser for a nuclear power plant with error prediction

    SciTech Connect (OSTI)

    Kim, Keehoon.

    1992-01-01

    This thesis is part of an ongoing project at Iowa State University to develop ANN bases fault diagnostic systems to detect and classify operational transients at nuclear power plants.

  3. Effect of stacking fault energy on mechanism of plastic deformation in nanotwinned FCC metals

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

    Borovikov, Valery; Mendelev, Mikhail I.; King, Alexander H.; LeSar, Richard

    2015-05-15

    Starting from a semi-empirical potential designed for Cu, we have developed a series of potentials that provide essentially constant values of all significant (calculated) materials properties except for the intrinsic stacking fault energy, which varies over a range that encompasses the lowest and highest values observed in nature. In addition, these potentials were employed in molecular dynamics (MD) simulations to investigate how stacking fault energy affects the mechanical behavior of nanotwinned face-centered cubic (FCC) materials. The results indicate that properties such as yield strength and microstructural stability do not vary systematically with stacking fault energy, but rather fall into twomore » distinct regimes corresponding to 'low' and 'high' stacking fault energies.« less

  4. On-line early fault detection and diagnosis of municipal solid waste incinerators

    SciTech Connect (OSTI)

    Zhao Jinsong [College of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China)], E-mail: jinsongzhao@mail.tsinghua.edu.cn; Huang Jianchao [College of Information Science and Technology, Beijing Institute of Technology, Beijing 10086 (China); Sun Wei [College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029 (China)

    2008-11-15

    A fault detection and diagnosis framework is proposed in this paper for early fault detection and diagnosis (FDD) of municipal solid waste incinerators (MSWIs) in order to improve the safety and continuity of production. In this framework, principal component analysis (PCA), one of the multivariate statistical technologies, is used for detecting abnormal events, while rule-based reasoning performs the fault diagnosis and consequence prediction, and also generates recommendations for fault mitigation once an abnormal event is detected. A software package, SWIFT, is developed based on the proposed framework, and has been applied in an actual industrial MSWI. The application shows that automated real-time abnormal situation management (ASM) of the MSWI can be achieved by using SWIFT, resulting in an industrially acceptable low rate of wrong diagnosis, which has resulted in improved process continuity and environmental performance of the MSWI.

  5. Method and system for early detection of incipient faults in electric motors

    DOE Patents [OSTI]

    Parlos, Alexander G; Kim, Kyusung

    2003-07-08

    A method and system for early detection of incipient faults in an electric motor are disclosed. First, current and voltage values for one or more phases of the electric motor are measured during motor operations. A set of current predictions is then determined via a neural network-based current predictor based on the measured voltage values and an estimate of motor speed values of the electric motor. Next, a set of residuals is generated by combining the set of current predictions with the measured current values. A set of fault indicators is subsequently computed from the set of residuals and the measured current values. Finally, a determination is made as to whether or not there is an incipient electrical, mechanical, and/or electromechanical fault occurring based on the comparison result of the set of fault indicators and a set of predetermined baseline values.

  6. Real-time sub- Å ngstrom imaging of reversible and irreversible...

    Office of Scientific and Technical Information (OSTI)

    Real-time sub- ngstrom imaging of reversible and irreversible conformations in rhodium catalysts and graphene Title: Real-time sub- ngstrom imaging of reversible and ...

  7. Fault isolation through no-overhead link level CRC

    DOE Patents [OSTI]

    Chen, Dong; Coteus, Paul W.; Gara, Alan G.

    2007-04-24

    A fault isolation technique for checking the accuracy of data packets transmitted between nodes of a parallel processor. An independent crc is kept of all data sent from one processor to another, and received from one processor to another. At the end of each checkpoint, the crcs are compared. If they do not match, there was an error. The crcs may be cleared and restarted at each checkpoint. In the preferred embodiment, the basic functionality is to calculate a CRC of all packet data that has been successfully transmitted across a given link. This CRC is done on both ends of the link, thereby allowing an independent check on all data believed to have been correctly transmitted. Preferably, all links have this CRC coverage, and the CRC used in this link level check is different from that used in the packet transfer protocol. This independent check, if successfully passed, virtually eliminates the possibility that any data errors were missed during the previous transfer period.

  8. Late Cenozoic fault kinematics and basin development, Calabrian arc, Italy

    SciTech Connect (OSTI)

    Knott, S.D.; Turco, E.

    1988-08-01

    Current views for explaining the present structure of the Calabrian arc emphasize bending or buckling of an initially straight zone by rigid indentation. Although bending has played an important role, bending itself cannot explain all structural features now seen in the arc for the following reasons: (1) across-arc extension is inconsistent with buckling, (2) north-south compression predicted by a bending mechanism to occur in the internal part of a curved mountain belt is not present in the Calabrian arc, and (3) lateral shear occurs throughout the arc, not just along the northern and southern boundaries. The model presented here is based on lateral bending of mantle and lower crust (demonstrated by variation in extension in the Tyrrhenian basin) and semibrittle faulting and block rotation in the upper crust. These two styles of deformation are confined to the upper plate of the Calabrian subduction system. This deformation is considered to have been active from the beginning of extension in the Tyrrhenian basin (late Tortonian) and is still active today (based on Holocene seismicity). Block rotations are a consequence of lateral heterogeneous shear during extension. Therefore, some of the observed rotation of paleo-magnetic declinations may have occurred in areas undergoing extension and not just during thrusting. Inversion of sedimentary basins by block rotation is predicted by the model. The model will be a useful aid in interpreting reflection seismic data and exploring and developing offshore and onshore sedimentary basins in southern Italy.

  9. Effects of stacking faults on the electronic structures of quantum rods

    SciTech Connect (OSTI)

    Wang, Lin-Wang

    2004-03-30

    Atomistic semiempirical pseudopotential method is used to study the effects of stacking faults in a wurtzite structure quantum rod. It is found that a single stacking fault can cause a 10-50 meV change in the conduction state eigen energy, and a localization in the electron wave function. However, the effects on the hole eigen energies and wave functions are very small.

  10. VOLTTRON Compatible Whole-Building Root-Fault Detection and Diagnosis |

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

    Department of Energy VOLTTRON Compatible Whole-Building Root-Fault Detection and Diagnosis VOLTTRON Compatible Whole-Building Root-Fault Detection and Diagnosis Planned mixed-use demonstration site on Drexel University campus. Planned mixed-use demonstration site on Drexel University campus. Photo courtesy Drexel University. Photo courtesy Drexel University. Planned mixed-use demonstration site on Drexel University campus. Photo courtesy Drexel University. Lead Performer: Drexel University -

  11. Volttron Implementation: Automated Fault Detection and Diagnosis for AHU-VAV Systems

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

    Volttron Implementation: Automated Fault Detection and Diagnosis for AHU-VAV Systems 1 Volttron Workshop 23 July 2015 Arlington, VA Adam Regnier Jin Wen, Ph.D. Building Science & Engineering Group Drexel University Philadelphia, PA Outline/Agenda o Platform overview o Drivers o Database o Agents 4. Why Volttron? o Benefits for research & for industry 5. Going Forward Overview/Agenda 1. Introduction o Faults in AHU-VAV Systems 2. Diagnostics o Methods & Requirements 3. Volttron

  12. Apparatus for and method of testing an electrical ground fault circuit interrupt device

    DOE Patents [OSTI]

    Andrews, Lowell B.

    1998-01-01

    An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined.

  13. Apparatus for and method of testing an electrical ground fault circuit interrupt device

    DOE Patents [OSTI]

    Andrews, L.B.

    1998-08-18

    An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined. 17 figs.

  14. Pen Branch fault program: Consolidated report on the seismic reflection surveys and the shallow drilling

    SciTech Connect (OSTI)

    Stieve, A.L.; Stephenson, D.E.; Aadland, R.K.

    1991-03-23

    The Pen Branch fault was identified in the subsurface at the Savannah River Site (SRS) in 1989 based upon interpretation of earlier seismic reflection surveys and other geologic investigations (Seismorgraph Services Incorp., 1973; Chapman and DiStefano, 1989; Snipes, Fallaw and Price, 1989). A program was initiated at that time to determine the capability of the fault to release seismic energy (Price and others, 1989) as defined in the Nuclear Regulatory Commission regulatory guidelines, 10 CFR 100 Appendix A. This report presents the results of the Pen Branch fault investigation based on data acquired from seismic reflection surveys and shallow drilling across the fault completed at this time. The Earth Science Advisory Committee (ESAC) has reviewed the results of these investigations and unanimously agrees with the conclusion of Westinghouse Savannah River Company (WSRC) that the Pen Branch fault is a non-capable fault. ESAC is a committee of 12 earth science professionals from academia and industry with the charter of providing outside peer review of SRS geotechnical, seismic, and ground water modeling programs.

  15. Fault-tolerant interconnection network and image-processing applications for the PASM parallel processing system

    SciTech Connect (OSTI)

    Adams, G.B. III

    1984-01-01

    The demand for very high speed data processing coupled with falling hardware costs has made large-scale parallel and distributed computer systems both desirable and feasible. Two modes of parallel processing are single instruction stream-multiple data stream (SIMD) and multiple instruction stream-multiple data stream (MIMD). PASM, a partitionable SIMD/MIMD system, is a reconfigurable multimicroprocessor system being designed for image processing and pattern recognition. An important component of these systems is the interconnection network, the mechanism for communication among the computation nodes and memories. Assuring high reliability for such complex systems is a significant task. Thus, a crucial practical aspect of an interconnection network is fault tolerance. In answer to this need, the Extra Stage Cube (ESC), a fault-tolerant, multistage cube-type interconnection network, is define. The fault tolerance of the ESC is explored for both single and multiple faults, routing tags are defined, and consideration is given to permuting data and partitioning the ESC in the presence of faults. The ESC is compared with other fault-tolerant multistage networks. Finally, reliability of the ESC and an enhanced version of it are investigated.

  16. Criteria for design of the Yucca Mountain structures, systems and components for fault displacement

    SciTech Connect (OSTI)

    Stepp, C.; Hossain, Q.; Nesbit, S.; Hardy, M.

    1995-12-31

    The DOE intends to design the Yucca Mountain high-level waste facility structures, systems and components (SSCs) for fault displacements to provide reasonable assurance that they will meet the preclosure safety performance objectives established by 10 CFR Part 60. To the extent achievable, fault displacement design of the facility will follow guidance provided in the NRC Staff Technical Position. Fault avoidance will be the primary design criterion, especially for spatially compact or clustered SSCs. When fault avoidance is not reasonably achievable, expected to be the case for most spatially extended SSCs, engineering design procedures and criteria or repair and rehabilitation actions, depending on the SSC`s importance to safety, are provided. SSCs that have radiological safety importance will be designed for fault displacements that correspond to the hazard exceedance frequency equal to their established seismic safety performance goals. Fault displacement loads are generally localized and may cause local inelastic response of SSCs. For this reason, the DOE intends to use strain-based design acceptance criteria similar to the strain-based criteria used to design nuclear plant SSCs for impact and impulsive loads.

  17. Lower hybrid accessibility in a large, hot reversed field pinch

    SciTech Connect (OSTI)

    Dziubek, R.A.; Harvey, R.W.; Hokin, S.A.; Uchimoto, E.

    1995-11-01

    Accessibility and damping of the slow wave in a reversed field pinch (RFP) plasma is investigated theoretically, using projected Reversed Field Experiment (RFX) plasma parameters. By numerically solving the hot plasma dispersion relation, regions of propagation are found and the possibility of mode conversion is analyzed. If the parallel index of refraction of the wave is chosen judiciously at the edge of the plasma, the slow wave is accessible to a target region located just inside the reversal surface without mode conversion. Landau damping is also optimized in this region. A representative fast electron population is then added in order to determine its effect on accessibility and damping. The presence of these electrons, whose parameters were estimated by extrapolation of Madison Symmetric Torus (MST) data, does not affect the accessibility of the wave. However, the initial phase velocity of the wave needs to be increased somewhat in order to maintain optimal damping in the target zone.

  18. Implications of Scheduled ITC Reversion for RPS Compliance: Preliminary Results

    SciTech Connect (OSTI)

    Lowder, Travis; Miller, John; O'Shaughnessy, Eric; Heeter, Jenny

    2015-09-14

    This poster presents DRAFT initial results of a forthcoming NREL analysis. The analysis investigates the impacts of the scheduled investment tax credit (ITC) reversion from 30 percent to 10 percent for certain solar photovoltaic projects. Specifically, it considers whether the reversion will result in increased use of alternative compliance payments (ACPs) in lieu of solar renewable energy credits (SRECs) for renewable portfolio standard (RPS) compliance. The analysis models the effect of a 10 percent ITC on power purchase agreement (PPA) prices for non-residential systems in the eight states with solar carve-outs and solar ACPs. Our preliminary results suggest that states will likely install sufficient capacity to meet long-term targets through SRECs rather than ACPs following the ITC reversion. However, the analysis shows that the ITC reversion could affect project economics such that capacity shortfalls in certain states could temporarily increase the use of ACPs. NREL anticipates publishing a full report of this analysis in fall 2015. credits (SRECs) for renewable portfolio standard (RPS) compliance. The analysis models the effect of a 10 percent ITC on power purchase agreement (PPA) prices for non-residential systems in the eight states with solar carve-outs and solar ACPs. Our preliminary results suggest that states will likely install sufficient capacity to meet long-term targets through SRECs rather than ACPs following the ITC reversion. However, the analysis shows that the ITC reversion could affect project economics such that capacity shortfalls in certain states could temporarily increase the use of ACPs. NREL anticipates publishing a full report of this analysis in fall 2015.

  19. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Magnetic Vortex Core Reversal by Low-Field Excitations Print Wednesday, 28 March 2007 00:00 In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to

  20. Energy current imaging method for time reversal in elastic media

    SciTech Connect (OSTI)

    Anderson, Brian E; Ulrich, Timothy J; Le Bas, Pierre - Yves A; Larmat, Carene; Johnson, Paul A; Guyer, Robert A; Griffa, Michele

    2009-01-01

    An energy current imaging method is presented for use in locating sources of wave energy during the back propagation stage of the time reversal process. During the back propagation phase of an ideal time reversal experiment, wave energy coalesces from all angles of incidence to recreate the source event; after the recreation, wave energy diverges in every direction. An energy current imaging method based on this convergence/divergence behavior has been developed. The energy current imaging method yields a smaller spatial distribution for source reconstruction than is possible with traditional energy imaging methods.

  1. In-situ Characterization of Highly Reversible Phase Transformation by

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

    Synchrotron X-ray Laue Microdiffraction In-situ Characterization of Highly Reversible Phase Transformation by Synchrotron X-ray Laue Microdiffraction In-situ Characterization of Highly Reversible Phase Transformation by Synchrotron X-ray Laue Microdiffraction Print Monday, 23 May 2016 09:50 In situ measurement of the orientation matrices for the austenite and martensite phases of the alloy Cu25Au30Zn45 across the interface was performed by synchrotron x-ray Laue microdiffraction at the ALS.

  2. Modified polynomial function model for reversed field pinches

    SciTech Connect (OSTI)

    Shen, W.; Sprott, J.C.

    1990-11-01

    A generalized analytic representation for the magnetic field and current density profiles in a reversed field pinch is proposed. These profiles have zero current density at the wall and finite plasma pressure. The profiles are characterized by two free parameters here taken to be the field reversal parameter (F) and pinch parameter ({Theta}). From the profiles, many useful quantities such as magnetic energy, beta, inductane, resistance and ohmic input power are calculated. These quantities provide a basis for analyzing experimental data and performing electrical circuit modeling of RFP discharges. 19 refs., 9 figs.

  3. E-print Network : Main View : Search Results for Title: "Reversible...

    Office of Scientific and Technical Information (OSTI)

    Reversible control of spin-polarized supercurrents in ferromagnetic Josephson junctions" Author: Banerjee AND Robinson...

  4. Final Project Report: Self-Correcting Controls for VAV System Faults Filter/Fan/Coil and VAV Box Sections

    SciTech Connect (OSTI)

    Brambley, Michael R.; Fernandez, Nicholas; Wang, Weimin; Cort, Katherine A.; Cho, Heejin; Ngo, Hung; Goddard, James K.

    2011-05-01

    This report addresses original research by the Pacific Northwest National Laboratory for the California Institute for Energy and Environment on self-correcting controls for variable-air-volume (VAV) heating, ventilating and air-conditioning systems and focuses specifically on air handling and VAV box components of the air side of the system. A complete set of faults for these components was compiled and a fault mode analysis performed to understand the detectable symptoms of the faults and the chain of causation. A set of 26 algorithms was developed to facilitate the automatic correction of these faults in typical commercial VAV systems. These algorithms include training tests that are used during commissioning to develop models of normal system operation, passive diagnostics used to detect the symptoms of faults, proactive diagnostics used to diagnose the cause of a fault, and finally fault correction algorithms. Ten of the twenty six algorithms were implemented in a prototype software package that interfaces with a test bed facility at PNNL's Richland, WA, laboratory. Measurement bias faults were instigated in the supply-air temperature sensor and the supply-air flow meter to test the algorithms developed. The algorithms as implemented in the laboratory software correctly detected, diagnosed and corrected these faults. Finally, an economic and impact assessment was performed for the State of California for deployment of self-correcting controls. Assuming 15% HVAC energy savings and a modeled deployment profile, 3.1-5.8 TBu of energy savings are possible by year 15.

  5. Final Project Report. Scalable fault tolerance runtime technology for petascale computers

    SciTech Connect (OSTI)

    Krishnamoorthy, Sriram; Sadayappan, P

    2015-06-16

    With the massive number of components comprising the forthcoming petascale computer systems, hardware failures will be routinely encountered during execution of large-scale applications. Due to the multidisciplinary, multiresolution, and multiscale nature of scientific problems that drive the demand for high end systems, applications place increasingly differing demands on the system resources: disk, network, memory, and CPU. In addition to MPI, future applications are expected to use advanced programming models such as those developed under the DARPA HPCS program as well as existing global address space programming models such as Global Arrays, UPC, and Co-Array Fortran. While there has been a considerable amount of work in fault tolerant MPI with a number of strategies and extensions for fault tolerance proposed, virtually none of advanced models proposed for emerging petascale systems is currently fault aware. To achieve fault tolerance, development of underlying runtime and OS technologies able to scale to petascale level is needed. This project has evaluated range of runtime techniques for fault tolerance for advanced programming models.

  6. Symmetrical and Unsymmetrical Fault Currents of a Wind Power Plant: Preprint

    SciTech Connect (OSTI)

    Gevorgian, V.; Singh, M.; Muljadi, E.

    2011-12-01

    This paper investigates the short-circuit behavior of a wind power plant for different types of wind turbines. Both symmetrical faults and unsymmetrical faults are investigated. The size of wind power plants (WPPs) keeps getting bigger and bigger. The number of wind plants in the U.S. has increased very rapidly in the past 10 years. It is projected that in the U.S., the total wind power generation will reach 330 GW by 2030. As the importance of WPPs increases, planning engi-neers must perform impact studies used to evaluate short-circuit current (SCC) contribution of the plant into the transmission network under different fault conditions. This information is needed to size the circuit breakers, to establish the proper sys-tem protection, and to choose the transient suppressor in the circuits within the WPP. This task can be challenging to protec-tion engineers due to the topology differences between different types of wind turbine generators (WTGs) and the conventional generating units. This paper investigates the short-circuit behavior of a WPP for different types of wind turbines. Both symmetrical faults and unsymmetrical faults are investigated. Three different soft-ware packages are utilized to develop this paper. Time domain simulations and steady-state calculations are used to perform the analysis.

  7. Interplay between intrinsic and stacking-fault magnetic domains in bi-layered manganites

    SciTech Connect (OSTI)

    Hossain, M.A; Burkhardt, Mark H.; Sarkar, S.; Ohldag, H.; Chuang, Y.-D.; Scholl, A.; Young, A.T.; Doran, A.; Dessau, D.S.; Zheng, H.; Mitchell, J.F.; Durr, H.A.; Stohr, J.

    2012-09-11

    We present a low temperature X-ray photoemission electron microscopy study of the bi-layered manganite compound La{sub 1.2}Sr{sub 1.8}Mn{sub 2}O{sub 7} (BL-LSMO) to investigate the influence of stacking faults, which are structurally and magnetically different from the bi-layered host. In BL-LSMO small magnetic moment persists to T* = 300K, well above the Curie temperature of 120K (T{sub C}). Our magnetic images show that 3D stacking faults are responsible for the T* transition. Furthermore, close to the T{sub C}, stacking faults are well coupled to the bi-layered host with latter magnetic domains controlling the spin direction of the stacking faults. Contrary to recent reports, we find that stacking faults do not seed magnetic domains in the host via an exchange spring mechanism and the intrinsic T{sub C} of the BL-LSMO is not lower than 120K.

  8. FITL: Extending LLVM for the Translation of Fault-Injection Directives

    SciTech Connect (OSTI)

    Lee, Seyong; Vetter, Jeffrey S

    2015-01-01

    The frequency of hardware errors in HPC systems continues to grow as system designs evolve toward exascale. Tolerating these errors efficiently and effectively will require software-based resilience solutions. With this requirement in mind, recent research has increasingly employed LLVM-based tools to simulate transient hardware faults in order to study the resilience characteristics of specific applications. However, such tools require researchers to configure their experiments at the level of the LLVM intermediate representation (LLVM IR) rather than at the source level of the applications under study. In this paper, we present FITL (Fault-Injection Toolkit for LLVM), a set of LLVM extensions to which it is straightforward to translate source-level pragmas that specify fault injection. While we have designed FITL not to be tied to any particular compiler front end or high-level language, we also describe how we have extended our OpenARC compiler to translate a novel set of fault-injection pragmas for C to FITL. Finally, we present several resilience studies we have conducted using FITL, including a comparison with a source-level fault injector we have built as part of OpenARC.

  9. Reversing-counterpulse repetitive-pulse inductive storage circuit

    DOE Patents [OSTI]

    Honig, E.M.

    1987-02-10

    A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime. 10 figs.

  10. Rotational stability of a long field-reversed configuration

    SciTech Connect (OSTI)

    Barnes, D. C. Steinhauer, L. C.

    2014-02-15

    Rotationally driven modes of long systems with dominantly axial magnetic field are considered. We apply the incompressible model and order axial wavenumber small. A recently developed gyro-viscous model is incorporated. A one-dimensional equilibrium is assumed, but radial profiles are arbitrary. The dominant toroidal (azimuthal) mode numbers ℓ=1 and ℓ=2 modes are examined for a variety of non-reversed (B) and reversed profiles. Previous results for both systems with rigid rotor equilibria are reproduced. New results are obtained by incorporation of finite axial wavenumber and by relaxing the assumption of rigid electron and ion rotation. It is shown that the frequently troublesome ℓ=2 field reversed configuration (FRC) mode is not strongly affected by ion kinetic effects (in contrast to non-reversed cases) and is likely stabilized experimentally only by finite length effects. It is also shown that the ℓ=1 wobble mode has a complicated behavior and is affected by a variety of configuration and profile effects. The rotationally driven ℓ=1 wobble is completely stabilized by strong rotational shear, which is anticipated to be active in high performance FRC experiments. Thus, observed wobble modes in these systems are likely not driven by rotation alone.

  11. Simulation studies of nucleation of ferroelectric polarization reversal.

    SciTech Connect (OSTI)

    Brennecka, Geoffrey L.; Winchester, Benjamin Michael

    2014-08-01

    Electric field-induced reversal of spontaneous polarization is the defining characteristic of a ferroelectric material, but the process(es) and mechanism(s) associated with the initial nucleation of reverse-polarity domains are poorly understood. This report describes studies carried out using phase field modeling of LiTaO3, a relatively simple prototype ferroelectric material, in order to explore the effects of either mechanical deformation or optically-induced free charges on nucleation and resulting domain configuration during field-induced polarization reversal. Conditions were selected to approximate as closely as feasible those of accompanying experimental work in order to provide not only support for the experimental work but also ensure that additional experimental validation of the simulations could be carried out in the future. Phase field simulations strongly support surface mechanical damage/deformation as effective for dramatically reducing the overall coercive field (Ec) via local field enhancements. Further, optically-nucleated polarization reversal appears to occur via stabilization of latent nuclei via the charge screening effects of free charges.

  12. Reversing-counterpulse repetitive-pulse inductive storage circuit

    DOE Patents [OSTI]

    Honig, Emanuel M.

    1987-01-01

    A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.

  13. Reversing-counterpulse repetitive-pulse inductive storage circuit

    DOE Patents [OSTI]

    Honig, E.M.

    1984-06-05

    A high power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.

  14. Single line reversing system capsular pneumatic freight pipelines

    SciTech Connect (OSTI)

    Weaver, P.B.

    1999-07-01

    In the 1800's the first Pneumatic Tube Systems sent a carrier vertically from one floor to another in a hospital using a foot-powered bellows. The carrier was returned to the starting point down the same tube using gravity. This was the first Single Line Reversing system. As the stations were moved apart horizontally the foot-powered bellows at both ends became ineffective and were replaced with a single blower or exhauster. The blower/exhauster ran continuously therefore a second line for returning carriers to the starting point, had to be installed - hence Twin Line systems. These systems were used for transporting mail, paperwork, medications, steel mill samples, parts, tools, medical lab samples, etc., in hospitals, stores and other businesses. Twin Line systems were very popular until about 1970 at which time installation labor and material costs became expensive and controls were becoming unnecessarily complicated and expensive. These reasons plus new technology forced the return to Single Line Reversing technology. Back in the 1800's three ``people transporting'' subways were built. A fourth system was built under the Pentagon in the 1950's or 1960's. It is difficult to find information on this one. All are Single Line Reversing systems. The difference between a Single Line Reversing and a Twin Line system is exactly as the names imply. The principle of the operation of these systems is covered herein. The physics for these two kinds of systems is the same. The Single Line Reversing system is technically more complex but capital and operating expense is far less costly. These costs are discussed herein.

  15. Embedded atom calculations of unstable stacking fault energies and surface energies in intermetallics

    SciTech Connect (OSTI)

    Farkas, D.; Zhou, S.J.; Vailhe, C.; Mutasa, B.; Panova, J.

    1997-01-01

    We performed embedded atom method calculations on surface energies and unstable stacking fault energies for a series of intermetallics for which interatomic potentials of the embedded atom type have recently been developed. These results were analyzed and applied to the prediction of relative ductility of these materials using the various current theories. Series of alloys with the B2 ordered structure were studied, and the results were compared to those in pure body-centered cubic (bcc) Fe. Ordered compounds with L1{sub 2} and L1{sub 0} structures based on the face-centered cubic (fcc) lattice were also studied. It was found that there is a correlation between the values of the antiphase boundary (APB) energies in B2 alloys and their unstackable stacking fault energies. Materials with higher APB energies tend to have higher unstable stacking fault energies, leading to an increased tendency to brittle fracture. {copyright} {ital 1997 Materials Research Society.}

  16. Methods and apparatus using commutative error detection values for fault isolation in multiple node computers

    DOE Patents [OSTI]

    Almasi, Gheorghe [Ardsley, NY; Blumrich, Matthias Augustin [Ridgefield, CT; Chen, Dong [Croton-On-Hudson, NY; Coteus, Paul [Yorktown, NY; Gara, Alan [Mount Kisco, NY; Giampapa, Mark E. [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Hoenicke, Dirk I. [Ossining, NY; Singh, Sarabjeet [Mississauga, CA; Steinmacher-Burow, Burkhard D. [Wernau, DE; Takken, Todd [Brewster, NY; Vranas, Pavlos [Bedford Hills, NY

    2008-06-03

    Methods and apparatus perform fault isolation in multiple node computing systems using commutative error detection values for--example, checksums--to identify and to isolate faulty nodes. When information associated with a reproducible portion of a computer program is injected into a network by a node, a commutative error detection value is calculated. At intervals, node fault detection apparatus associated with the multiple node computer system retrieve commutative error detection values associated with the node and stores them in memory. When the computer program is executed again by the multiple node computer system, new commutative error detection values are created and stored in memory. The node fault detection apparatus identifies faulty nodes by comparing commutative error detection values associated with reproducible portions of the application program generated by a particular node from different runs of the application program. Differences in values indicate a possible faulty node.

  17. Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling

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

    Unit-Variable Air Volume and Air Handling Unit-Constant Air Volume Systems - 2014 BTO Peer Review | Department of Energy Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit-Variable Air Volume and Air Handling Unit-Constant Air Volume Systems - 2014 BTO Peer Review Compatible and Cost-Effective Fault Diagnostic Solutions for Air Handling Unit-Variable Air Volume and Air Handling Unit-Constant Air Volume Systems - 2014 BTO Peer Review Presenter: Jin Wen, Drexel

  18. Microsoft PowerPoint - HPC - Resilience-Fault Injection Research Penta_Final [Compatibility Mode]

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

    3146 This document is approved for public release; further dissemination unlimited Resilience / Fault Injection Research ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 0 10 20 30 40 50 60 70 80 32PB 64PB 96PB 128PB System Memory Capacity Uncorrected Error Rate (Relative to Cielo) ● ● ● ● ● ● 8Gbit / High FIT 8Gbit / Low FIT 16Gbit / High FIT 16Gbit / Low FIT 32Gbit / High FIT 32Gbit / Low FIT Resilience / Fault Injection Research

  19. Preliminary 3d depth migration of a network of 2d seismic lines for fault

    Office of Scientific and Technical Information (OSTI)

    imaging at a Pyramid Lake, Nevada geothermal prospect (Conference) | SciTech Connect Preliminary 3d depth migration of a network of 2d seismic lines for fault imaging at a Pyramid Lake, Nevada geothermal prospect Citation Details In-Document Search Title: Preliminary 3d depth migration of a network of 2d seismic lines for fault imaging at a Pyramid Lake, Nevada geothermal prospect Roxanna Frary, John N. Louie, Sathish Pullammanappallil, Amy Eisses, 2011, Preliminary 3d depth migration of a

  20. Detailed Geophysical Fault Characterization in Yucca Flat, Nevada Test Site, Nevada

    SciTech Connect (OSTI)

    Theodore H. Asch; Donald Sweetkind; Bethany L. Burton; Erin L. Wallin

    2009-02-10

    Yucca Flat is a topographic and structural basin in the northeastern part of the Nevada Test Site (NTS) in Nye County, Nevada. Between the years 1951 and 1992, 659 underground nuclear tests took place in Yucca Flat; most were conducted in large, vertical excavations that penetrated alluvium and the underlying Cenozoic volcanic rocks. Radioactive and other potential chemical contaminants at the NTS are the subject of a long-term program of investigation and remediation by the U.S. Department of Energy (DOE), National Nuclear Security Administration, Nevada Site Office, under its Environmental Restoration Program. As part of the program, the DOE seeks to assess the extent of contamination and to evaluate the potential risks to humans and the environment from byproducts of weapons testing. To accomplish this objective, the DOE Environmental Restoration Program is constructing and calibrating a ground-water flow model to predict hydrologic flow in Yucca Flat as part of an effort to quantify the subsurface hydrology of the Nevada Test Site. A necessary part of calibrating and evaluating a model of the flow system is an understanding of the location and characteristics of faults that may influence ground-water flow. In addition, knowledge of fault-zone architecture and physical properties is a fundamental component of the containment of the contamination from underground nuclear tests, should such testing ever resume at the Nevada Test Site. The goal of the present investigation is to develop a detailed understanding of the geometry and physical properties of fault zones in Yucca Flat. This study was designed to investigate faults in greater detail and to characterize fault geometry, the presence of fault splays, and the fault-zone width. Integrated geological and geophysical studies have been designed and implemented to work toward this goal. This report describes the geophysical surveys conducted near two drill holes in Yucca Flat, the data analyses performed, and the

  1. Superconducting matrix fault current limiter with current-driven trigger mechanism

    DOE Patents [OSTI]

    Yuan, Xing

    2008-04-15

    A modular and scalable Matrix-type Fault Current Limiter (MFCL) that functions as a "variable impedance" device in an electric power network, using components made of superconducting and non-superconducting electrically conductive materials. An inductor is connected in series with the trigger superconductor in the trigger matrix and physically surrounds the superconductor. The current surge during a fault will generate a trigger magnetic field in the series inductor to cause fast and uniform quenching of the trigger superconductor to significantly reduce burnout risk due to superconductor material non-uniformity.

  2. The Wallula fault and tectonic framework of south-central Washington, as interpreted from magnetic and gravity anomalies

    SciTech Connect (OSTI)

    Blakely, Richard J.; Sherrod, Brian; Weaver, Craig; Wells, Ray E.; Rohay, Alan C.

    2014-06-11

    Magnetic and gravity data, collected in south-central Washington near the Yakima Fold and Thrust Belt (YFTB) are used to model upper crustal structure, the extent of the late Columbia River Basalt flow named the Ice Harbor member, the vertical conduits (dikes) that the Ice Harbor erupted from, and whether the dikes are offset or affected by faulting on the Wallula Fault zone.

  3. Geometry and controls on fracturing in a natural fault-bend fold: Rosario field, Maracaibo basin, Venezuela

    SciTech Connect (OSTI)

    Apotria, T.G.; Wilkerson, M.S.; Knewtson, S.L.

    1996-08-01

    The Rosario oil field lies between the Perija Mountain front and Lake Maracaibo and produces from fractured Cretaceous carbonates and Tertiary clastics. We interpret the structure as a detached fault-bend fold which ramps through Cretaceous Cogollo and La Luna carbonates and flattens into an upper detachment at the base of the Upper Cretaceous Colon Shale. The structural relief formed primarily during the Mid Miocene and younger. Seismic and well control on the three-dimensional geometry illustrates the effects of (1) lithology and displacement variation on fold geometry, (2) an oblique footwall ramp on hangingwall faulting, and (3) fold curvature on fracturing and hydrocarbon production. Fold geometry at different structural levels is strongly controlled by lithology. Stiff Cogollo and La Luna carbonates exhibit kink-style folding above the upper fault-bend. The weak Colon Shale decouples the faulted carbonates from the concentrically folded Tertiary clastics. Regions of enhanced faulting and fracturing of Cretaceous carbonates are a function of structural position. We observe normal faults in the hangingwall where the strike of the footwall ramp changes from N20{degrees}E to N65{degrees}E. Fold curvature highlights fold hinges, yet distributed faulting is seismically imaged in the forelimb, suggesting that rocks fracture as they migrate through the ramp-upper flat fault-bend. Production rates are higher near the forelimb relative to the flat crestal region.

  4. Forward and reverse control system for induction motors

    DOE Patents [OSTI]

    Wright, J.T.

    1987-09-15

    A control system for controlling the direction of rotation of a rotor of an induction motor includes an array of five triacs with one of the triacs applying a current of fixed phase to the windings of the rotor and four of the triacs being switchable to apply either hot ac current or return ac current to the stator windings so as to reverse the phase of current in the stator relative to that of the rotor and thereby reverse the direction of rotation of the rotor. Switching current phase in the stator is accomplished by operating the gates of pairs of the triacs so as to connect either hot ac current or return ac current to the input winding of the stator. 1 fig.

  5. Two-step polarization reversal in biased ferroelectrics

    SciTech Connect (OSTI)

    Daniels, John E. Ukritnukun, Supphatuch; Glaum, Julia; Cozzan, Clayton; Tutuncu, Goknur; Dosch, Chris; Andrieux, Jerome; Jo, Wook; Jones, Jacob L.

    2014-06-14

    Polarization reversal in polycrystalline ferroelectrics is shown to occur via two distinct and sequential domain reorientation steps. This reorientation sequence, which cannot be readily discriminated in the overall sample polarization, is made apparent using time-resolved high-energy x-ray diffraction. Upon application of electric fields opposite to the initial poling direction, two unique and significantly different time constants are observed. The first (faster time constant) is shown to be derived by the release of a residual stress due to initial electrical biasing and the second (slower time constant) due to the redevelopment of residual stress during further domain wall motion. A modified domain reorientation model is given that accurately describes the domain volume fraction evolution during the reversal process.

  6. Treatment of produced waters by electrocoagulation and reverse osmosis

    SciTech Connect (OSTI)

    Tuggle, K.; Humenick, M.; Barker, F.

    1992-08-01

    Two oil field produced waters and one coal bed methane produced water from Wyoming were treated with electrocoagulation and reverse osmosis. All three produced waters would require treatment to meet the new Wyoming Department of Environmental Quality requirements for effluent discharge into a class III or IV stream. The removal of radium 226 and oil and grease was the primary focus of the study. Radium 226 and oil and grease were removed from the produced waters with electrocoagulation. The best removal of radium 226 (>84%) was achieved with use of a non-sacrificial anode (titanium). The best removal of oil and grease (>93%) was achieved using a sacrificial anode (aluminum). By comparison, reverse osmosis removed up to 87% of the total dissolved solids and up to 95% of the radium 226.

  7. Fast chirality reversal of the magnetic vortex by electric current

    SciTech Connect (OSTI)

    Lim, W. L. Liu, R. H.; Urazhdin, S.; Tyliszczak, T.; Erokhin, S. G.; Berkov, D.

    2014-12-01

    The possibility of high-density information encoding in magnetic materials by topologically stable inhomogeneous magnetization configurations such as domain walls, skyrmions, and vortices has motivated intense research into mechanisms enabling their control and detection. While the uniform magnetization states can be efficiently controlled by electric current using magnetic multilayer structures, this approach has proven much more difficult to implement for inhomogeneous states. Here, we report direct observation of fast reversal of magnetic vortex by electric current in a simple planar structure based on a bilayer of spin Hall material Pt with a single microscopic ferromagnetic disk contacted by asymmetric electrodes. The reversal is enabled by a combination of the chiral Oersted field and spin current generated by the nonuniform current distribution in Pt. Our results provide a route for the efficient control of inhomogeneous magnetization configurations by electric current.

  8. Thoughts Regarding the Dimensions of Faults at Rainier and Aqueduct Mesas, Nye County, Nevada, Based on Surface and Underground Mapping

    SciTech Connect (OSTI)

    Drellack, S.L.; Prothro, L.B.; Townsend, M.J.; Townsend, D.R.

    2011-02-01

    The geologic setting and history, along with observations through 50 years of detailed geologic field work, show that large-displacement (i.e., greater than 30 meters of displacement) syn- to post-volcanic faults are rare in the Rainier Mesa area. Faults observed in tunnels and drill holes are mostly tight, with small displacements (most less than 1.5 meters) and small associated damage zones. Faults are much more abundant in the zeolitized tuffs than in the overlying vitric tuffs, and there is little evidence that faults extend downward from the tuff section through the argillic paleocolluvium into pre-Tertiary rocks. The differences in geomechanical characteristics of the various tuff lithologies at Rainier Mesa suggest that most faults on Rainer Mesa are limited to the zeolitic units sandwiched between the overlying vitric bedded tuffs and the underlying pre-Tertiary units (lower carbonate aquifer3, lower clastic confining unit1, and Mesozoic granite confining unit).

  9. Advanced Catalysts and MEAs for Reversible Alkaline Membrane Fuel Cells

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

    Catalysts and MEAs for Reversible Alkaline Membrane Fuel Cells Hui Xu (PI) Giner Inc Newton, MA This presentation does not contain any proprietary, confidential, or otherwise restricted information DOE Catalyst Work Group Meeting June 8, 2015 2 Barriers Addressed * Activity (catalyst; MEA) * Durability (catalyst; MEA) * Cost (catalyst; MEA) Technical Targets * Design and develop ORR/OER bi-functional oxide catalysts * Integrate ORR/OER bifunctional oxide catalysts and alkaline membranes to

  10. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  11. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  12. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  13. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  14. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  15. Reversible and irreversible ion migration processes in lead halide

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

    perovskites for photovoltaics | MIT-Harvard Center for Excitonics Reversible and irreversible ion migration processes in lead halide perovskites for photovoltaics March 9, 2016 at 4:30 PM/36-462 Eric Hoke Stanford University, Draper Laboratory hoke-eric Lead hybrid perovskites are a promising family of photovoltaic absorber materials that have achieved power conversion efficiencies of over 20%. Lead halide perovskites are ionic materials with a low lattice energy which are unusual properties

  16. Understanding the Initial Stages of Reversible Mg Deposition and Stripping

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

    in Inorganic Nonaqueous Electrolytes - Joint Center for Energy Storage Research April 8, 2015, Research Highlights Understanding the Initial Stages of Reversible Mg Deposition and Stripping in Inorganic Nonaqueous Electrolytes MgCl+ Desolvation Diagram Scientific Achievement The chemical species at the Mg-anode surface in the presence of Magnesium Aluminum-Chloro complex (MACC) electrolyte were identified. While solvent molecules (THF and DME) are loosely bound at the Mg(0001) surface, the

  17. Progress on the Development of Reversible SOFC Stack Technology

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

    the Development of Reversible SOFC Stack Technology Presented by: Casey Brown 19 April 2011 Copyright © 2011 Versa Power Systems - All Rights Reserved Versa Power Systems * Versa Power Systems is a developer of planar solid oxide fuel cells (SOFCs) * Privately held company headquartered in Littleton, Colorado, United States * SOFC development facility in Calgary, Alberta, Canada * Activities in both stationary and mobile SOFC development Copyright © 2011 Versa Power Systems - All Rights

  18. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  19. Magnetic Vortex Core Reversal by Low-Field Excitations

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

    Magnetic Vortex Core Reversal by Low-Field Excitations Print In micrometer-sized magnetic thin films, the magnetization typically adopts an in-plane, circular configuration known as a magnetic vortex. At the vortex core, the magnetization turns sharply out of the plane, pointing either up or down. Magnetic data storage based on this binary phenomenon is an intriguing concept, but it would require the ability to flip the vortex cores on demand. Because these structures are highly stable, very

  20. Reversible geling co-polymer and method of making

    DOE Patents [OSTI]

    Gutowska, Anna

    2005-12-27

    The present invention is a thereapeutic agent carrier having a thermally reversible gel or geling copolymer that is a linear random copolymer of an [meth-]acrylamide derivative and a hydrophilic comonomer, wherein the linear random copolymer is in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum geling molecular weight cutoff and a therapeutic agent.

  1. Corrosion/erosion pipe inspection using reverse geometry radiography

    SciTech Connect (OSTI)

    Albert, R.D.

    1996-07-01

    Measurement of corrosion in piping was studied using the Digiray Reverse Geometry X-ray{reg_sign} (RGX{reg_sign}) imaging system during a series of field tests. Sponsored by Shell, Exxon and Mobil oil companies, these were recently carried out at the Shell Martinez refinery facility. Results of the field tests as well as other RGX radiographs taken in the laboratory by Digiray will be described in this report.

  2. Cooling by Time Reversal of Atomic Matter Waves

    SciTech Connect (OSTI)

    Martin, J.; Georgeot, B.; Shepelyansky, D. L. [Laboratoire de Physique Theorique, Universite de Toulouse III, CNRS, 31062 Toulouse (France)

    2008-02-01

    We propose an experimental scheme which allows us to realized approximate time reversal of matter waves for ultracold atoms in the regime of quantum chaos. We show that a significant fraction of the atoms return back to their original state, being at the same time cooled down by several orders of magnitude. We give a theoretical description of this effect supported by extensive numerical simulations. The proposed scheme can be implemented with existing experimental setups.

  3. Dynamic processes in field-reversed-configuration compact toroids

    SciTech Connect (OSTI)

    Rej, D.J.

    1987-01-01

    In this lecture, the dynamic processes involved in field-reversed configuration (FRC) formation, translation, and compression will be reviewed. Though the FRC is related to the field-reversed mirror concept, the formation method used in most experiments is a variant of the field-reversed THETA-pinch. Formation of the FRC eqilibrium occurs rapidly, usually in less than 20 ..mu..s. The formation sequence consists of several coupled processes: preionization; radial implosion and compression; magnetic field line closure; axial contraction; equilibrium formation. Recent experiments and theory have led to a significantly improved understanding of these processes; however, the experimental method still relies on a somewhat empirical approach which involves the optimization of initial preionization plasma parameters and symmetry. New improvements in FRC formation methods include the use of lower voltages which extrapolate better to larger devices. The axial translation of compact toroid plasmas offers an attractive engineering convenience in a fusion reactor. FRC translation has been demonstrated in several experiments worldwide, and these plasmas are found to be robust, moving at speeds up to the Alfven velocity over distances of up to 16 m, with no degradation in the confinement. Compact toroids are ideal for magnetic compression. Translated FRCs have been compressed and heated by imploding liners. Upcoming experiments will rely on external flux compression to heat a translater FRC at 1-GW power levels. 39 refs.

  4. Ab initio study of point defects near stacking faults in 3C-SiC

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

    Xi, Jianqi; Liu, Bin; Zhang, Yanwen; Weber, William J.

    2016-07-02

    Interactions between point defects and stacking faults in 3C-SiC are studied using an ab initio method based on density functional theory. The results show that the discontinuity of the stacking sequence considerably affects the configurations and behavior of intrinsic defects, especially in the case of silicon interstitials. The existence of an intrinsic stacking fault (missing a C-Si bilayer) shortens the distance between the tetrahedral-center site and its second-nearest-neighboring silicon layer, making the tetrahedral silicon interstitial unstable. Instead of a tetrahedral configuration with four C neighbors, a pyramid-like interstitial structure with a defect state within the band gap becomes a stablemore » configuration. In addition, orientation rotation occurs in the split interstitials that has diverse effects on the energy landscape of silicon and carbon split interstitials in the stacking fault region. Moreover, our analyses of ionic relaxation and electronic structure of vacancies show that the built-in strain field, owing to the existence of the stacking fault, makes the local environment around vacancies more complex than that in the bulk.« less

  5. Alleghanian development of the Goat Rock fault zone, southernmost Appalachians: Temporal compatibility with the master decollement

    SciTech Connect (OSTI)

    Steltenpohl, M.G. (Auburn Univ., AL (United States)); Goldberg, S.A. (Univ. of North Carolina, Chapel Hill (United States)); Hanley, T.B. (Columbus College, GA (United States)); Kunk, M.J. (Geological Survey, Reston, VA (United States))

    1992-09-01

    The Goat Rock and associated Bartletts Ferry fault zones, which mark the eastern margin of the Pine Mountain Grenville basement massif, are controversial due to the suggestion that they are rare exposed segments of the late Paleozoic southern Appalachian master decollement. The controversy in part stems from reported middle Paleozoic (Acadian) radiometric dates postulated as the time of movement along these fault zones. Ultramylonite samples from the type area at Goat Rock Dam yield a 287 [plus minus] 15 Ma Rb-Sr isochron interpreted as the time of Sr isotopic rehomgenization during mylonitization. This date is corroborated by Late Pennsylvanian-Early Permian [sup 40]Ar/[sup 39]Ar mineral ages on hornblende (297-288 Ma) and muscovite (285-278 Ma) from neomineralized and dynamically recrystallized rocks within and straddling the fault zone. These Late Pennsylvanian-Early Permian dates indicate the time of right-slip movement (Alleghenian) along the Goat Rock fault zone, which is compatible with the timing suggested by COCORP for thrusting along the southern Appalachian master decollement.

  6. Preliminary photovoltaic arc-fault prognostic tests using sacrificial fiber optic cabling.

    SciTech Connect (OSTI)

    Johnson, Jay; Blemel, Kenneth D.; Peter, Francis

    2013-02-01

    Through the New Mexico Small Business Assistance Program, Sandia National Laboratories worked with Sentient Business Systems, Inc. to develop and test a novel photovoltaic (PV) arc-fault detection system. The system operates by pairing translucent polymeric fiber optic sensors with electrical circuitry so that any external abrasion to the system or internal heating causes the fiber optic connection to fail or detectably degrade. A periodic pulse of light is sent through the optical path using a transmitter-receiver pair. If the receiver does not detect the pulse, an alarm is sounded and the PV system can be de-energized. This technology has the unique ability to prognostically determine impending failures to the electrical system in two ways: (a) the optical connection is severed prior to physical abrasion or cutting of PV DC electrical conductors, and (b) the polymeric fiber optic cable melts via Joule heating before an arc-fault is established through corrosion. Three arc-faults were created in different configurations found in PV systems with the integrated fiber optic system to determine the feasibility of the technology. In each case, the fiber optic cable was broken and the system annunciated the fault.

  7. A Reversible Structural Phase Transition in ZnV2O6 at High Pressures...

    Office of Scientific and Technical Information (OSTI)

    A Reversible Structural Phase Transition in ZnV2O6 at High Pressures Citation Details In-Document Search Title: A Reversible Structural Phase Transition in ZnV2O6 at High Pressures ...

  8. Flow reversal power limit for the HFBR (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Flow reversal power limit for the HFBR Citation Details In-Document Search Title: Flow reversal power limit for the HFBR You are accessing a document from the Department of ...

  9. Aerial photographic interpretation of lineaments and faults in late Cenozoic deposits in the eastern parts of the Saline Valley 1:100, 000 quadrangle, Nevada and California, and the Darwin Hills 1:100, 000 quadrangle, California

    SciTech Connect (OSTI)

    Reheis, M.C.

    1991-09-01

    Faults and fault-related lineaments in Quaternary and late Tertiary deposits in the southern part of the Walker Lane are potentially active and form patterns that are anomalous compared to those in most other areas of the Great Basin. Two maps at a scale of 1:100,000 summarize information about lineaments and faults in the area around and southwest of the Death Valley-Furnace Creek fault system based on extensive aerial-photo interpretation, limited field interpretation, limited field investigations, and published geologic maps. There are three major fault zones and two principal faults in the Saline Valley and Darwin Hills 1:100,000 quadrangles. (1) The Death Valley-Furnace Creek fault system and (2) the Hunter Mountain fault zone are northwest-trending right-lateral strike-slip fault zones. (3) The Panamint Valley fault zone and associated Towne Pass and Emigrant faults are north-trending normal faults. The intersection of the Hunter Mountain and Panamint Valley fault zones is marked by a large complex of faults and lineaments on the floor of Panamint Valley. Additional major faults include (4) the north-northwest-trending Ash Hill fault on the west side of Panamint Valley, and (5) the north-trending range-front Tin Mountain fault on the west side of the northern Cottonwood Mountains. The most active faults at present include those along the Death Valley-Furnace Creek fault system, the Tin Mountain fault, the northwest and southeast ends of the Hunter Mountain fault zone, the Ash Hill fault, and the fault bounding the west side of the Panamint Range south of Hall Canyon. Several large Quaternary landslides on the west sides of the Cottonwood Mountains and the Panamint Range apparently reflect slope instability due chiefly to rapid uplift of these ranges. 16 refs.

  10. Heterogeneous slip and rupture models of the San Andreas fault zone based upon three-dimensional earthquake tomography

    SciTech Connect (OSTI)

    Foxall, W.

    1992-11-01

    Crystal fault zones exhibit spatially heterogeneous slip behavior at all scales, slip being partitioned between stable frictional sliding, or fault creep, and unstable earthquake rupture. An understanding the mechanisms underlying slip segmentation is fundamental to research into fault dynamics and the physics of earthquake generation. This thesis investigates the influence that large-scale along-strike heterogeneity in fault zone lithology has on slip segmentation. Large-scale transitions from the stable block sliding of the Central 4D Creeping Section of the San Andreas, fault to the locked 1906 and 1857 earthquake segments takes place along the Loma Prieta and Parkfield sections of the fault, respectively, the transitions being accomplished in part by the generation of earthquakes in the magnitude range 6 (Parkfield) to 7 (Loma Prieta). Information on sub-surface lithology interpreted from the Loma Prieta and Parkfield three-dimensional crustal velocity models computed by Michelini (1991) is integrated with information on slip behavior provided by the distributions of earthquakes located using, the three-dimensional models and by surface creep data to study the relationships between large-scale lithological heterogeneity and slip segmentation along these two sections of the fault zone.

  11. Reversible Acid Gas Capture Using CO2-Binding Organic Liquids

    SciTech Connect (OSTI)

    Heldebrant, David J.; Koech, Phillip K.; Yonker, Clement R.; Rainbolt, James E.; Zheng, Feng

    2010-08-31

    Acid gas scrubbing technology is predominantly aqueous alkanolamine based. Of the acid gases, CO2, H2S and SO2 have been shown to be reversible, however there are serious disadvantages with corrosion and high regeneration costs. The primary scrubbing system composed of monoethanolamine is limited to 30% by weight because of the highly corrosive solution. This gravimetric limitation limits the CO2 volumetric (?108 g/L) and gravimetric capacity (?7 wt%) of the system. Furthermore the scrubbing system has a large energy penalty from pumping and heating the excess water required to dissolve the MEA bicarbonate salt. Considering the high specific heat of water (4 j/g-1K-1), low capacities and the high corrosion we set out to design a fully organic solvent that can chemically bind all acid gases i.e. CO2 as reversible alkylcarbonate ionic liquids or analogues thereof. Having a liquid acid gas carrier improves process economics because there is no need for excess solvent to pump and to heat. We have demonstrated illustrated in Figure 1, that CO2-binding organic liquids (CO2BOLs) have a high CO2 solubility paired with a much lower specific heat (<1.5 J/g-1K-1) than aqueous systems. CO2BOLs are a subsection of a larger class of materials known as Binding Organic Liquids (BOLs). Our BOLs have been shown to reversibly bind and release COS, CS2, and SO2, which we denote COSBOLS, CS2BOLs and SO2BOLs. Our BOLs are highly tunable and can be designed for post or pre-combustion gas capture. The design and testing of the next generation zwitterionic CO2BOLs and SO2BOLs are presented.

  12. Reversible Bending Fatigue Testing on Zry-4 Surrogate Rods

    SciTech Connect (OSTI)

    Wang, Jy-An John; Wang, Hong; Bevard, Bruce Balkcom; Howard, Rob L

    2014-01-01

    Testing high-burnup spent nuclear fuel (SNF) presents many challenges in areas such as specimen preparation, specimen installation, mechanical loading, load control, measurements, data acquisition, and specimen disposal because these tasks are complicated by the radioactivity of the test specimens. Research and comparison studies conducted at Oak Ridge National Laboratory (ORNL) resulted in a new concept in 2010 for a U-frame testing setup on which to perform hot-cell reversible bending fatigue testing. Subsequently, the three-dimensional finite element analysis and the engineering design of components were completed. In 2013 the ORNL team finalized the upgrade of the U-frame testing setup and the integration of the U-frame setup into a Bose dual linear motor test bench to develop a cyclic integrated reversible-bending fatigue tester (CIRFT). A final check was conducted on the CIRFT test system in August 2013, and the CIRFT was installed in the hot cell in September 2013 to evaluate both the static and dynamic mechanical response of SNF rods under simulated loads. The fatigue responses of Zircaloy-4 (Zry-4) cladding and the role of pellet pellet and pellet clad interactions are critical to SNF vibration integrity, but such data are not available due to the unavailability of an effective testing system. While the deployment of the developed CIRFT test system in a hot cell will provide the opportunity to generate the data, the use of a surrogate rod has proven quite effective in identifying the underlying deformation mechanism of an SNF composite rod under an equivalent loading condition. This paper presents the experimental results of using surrogate rods under CIRFT reversible cyclic loading. Specifically, monotonic and cyclic bending tests were conducted on surrogate rods made of a Zry-4 tube and alumina pellet inserts, both with and without an epoxy bond.

  13. Error-field penetration in reversed magnetic shear configurations

    SciTech Connect (OSTI)

    Wang, H. H.; Wang, Z. X.; Wang, X. Q. [MOE Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)] [MOE Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Wang, X. G. [School of Physics, Peking University, Beijing 100871 (China)] [School of Physics, Peking University, Beijing 100871 (China)

    2013-06-15

    Error-field penetration in reversed magnetic shear (RMS) configurations is numerically investigated by using a two-dimensional resistive magnetohydrodynamic model in slab geometry. To explore different dynamic processes in locked modes, three equilibrium states are adopted. Stable, marginal, and unstable current profiles for double tearing modes are designed by varying the current intensity between two resonant surfaces separated by a certain distance. Further, the dynamic characteristics of locked modes in the three RMS states are identified, and the relevant physics mechanisms are elucidated. The scaling behavior of critical perturbation value with initial plasma velocity is numerically obtained, which obeys previously established relevant analytical theory in the viscoresistive regime.

  14. Overview of results from the MST reversed field pinch experiment

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

    38 Please note that terms and conditions apply. Overview of results from the MST reversed field pinch experiment View the table of contents for this issue, or go to the journal homepage for more 2015 Nucl. Fusion 55 104006 (http://iopscience.iop.org/0029-5515/55/10/104006) Home Search Collections Journals About Contact us My IOPscience | International Atomic Energy Agency Nuclear Fusion Nucl. Fusion 55 (2015) 104006 (8pp) doi:10.1088/0029-5515/55/10/104006 Overview of results from the MST

  15. New Limit on Time-Reversal Violation in Beta Decay

    SciTech Connect (OSTI)

    Mumm, H. P.; Chupp, T. E.; Cooper, R. L.; Coulter, K. P.; Freedman, S. J.; Fujikawa, B. K.; Garcia, A.; Jones, G. L.; Nico, J. S.; Thompson, A. K.; Trull, C. A.; Wietfeldt, F. E.; Wilkerson, J. F.

    2011-09-02

    We report the results of an improved determination of the triple correlation DP{center_dot}(p{sub e}xp{sub v}) that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the standard model. Our result is D=[-0.96{+-}1.89(stat){+-}1.01(sys)]x10{sup -4}. The corresponding phase between g{sub A} and g{sub V} is {phi}{sub AV}=180.013 deg. {+-}0.028 deg. (68% confidence level). This result represents the most sensitive measurement of D in nuclear {beta} decay.

  16. Perturbative transport studies in the reversed-field pinch

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

    Perturbative transport studies in the reversed-field pinch This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2005 Nucl. Fusion 45 1342 (http://iopscience.iop.org/0029-5515/45/11/015) Download details: IP Address: 128.104.166.233 The article was downloaded on 11/10/2010 at 22:09 Please note that terms and conditions apply. View the table of contents for this issue, or go to the journal homepage for more Home Search Collections Journals About

  17. Synthesis and magnetic reversal of bi-conical Ni nanostructures

    SciTech Connect (OSTI)

    Biziere, N.; Lassalle Ballier, R.; Viret, M.

    2011-09-15

    Template synthesis in polyethylene terephthalate (PET) membranes has been used to grow hour glass shaped nickel nanowires with a constriction in the range of tens of nanometers at the center. Anisotropic magnetoresistance measurements have been performed on a single nanowire to follow magnetization reversal of the structure. The results are explained via 3D micromagnetic simulations showing the appearance of a complex vortex state close to the constriction whose propagation depends on the angle between the cone axis and the applied field. The interest of this original growth process for spintronics is discussed.

  18. A method to determine fault vectors in 4H-SiC from stacking sequences observed on high resolution transmission electron microscopy images

    SciTech Connect (OSTI)

    Wu, Fangzhen; Wang, Huanhuan; Raghothamachar, Balaji; Dudley, Michael; Mueller, Stephan G.; Chung, Gil; Sanchez, Edward K.; Hansen, Darren; Loboda, Mark J.; Zhang, Lihua; Su, Dong; Kisslinger, Kim; Stach, Eric

    2014-09-14

    A new method has been developed to determine the fault vectors associated with stacking faults in 4H-SiC from their stacking sequences observed on high resolution TEM images. This method, analogous to the Burgers circuit technique for determination of dislocation Burgers vector, involves determination of the vectors required in the projection of the perfect lattice to correct the deviated path constructed in the faulted material. Results for several different stacking faults were compared with fault vectors determined from X-ray topographic contrast analysis and were found to be consistent. This technique is expected to applicable to all structures comprising corner shared tetrahedra.

  19. Time reversal invariance - a test in free neutron decay

    SciTech Connect (OSTI)

    Lising, Laura J.

    1999-05-18

    Time reversal invariance violation plays only a small role in the Standard Model, and the existence of a T-violating effect above the predicted level would be an indication of new physics. A sensitive probe of this symmetry in the weak interaction is the measurement of the T-violating ''D''-correlation in the decay of free neutrons. The triple-correlation D{sigma}{sub n}{center_dot}p{sub e} x p{sub v} involves three kinematic variables, the neutron spin, electron momentu, and neutrino (or proton) momentum, and changes sign under time reversal. This experiment detects the decay products of a polarized cold neutron beam with an octagonal array of scintillation and solid-state detectors. Data from first run at NIST's Cold Neutron Research Facility give a D-coefficient of -0.1 {+-} 1.3(stat.) {+-} 0.7(syst) x 10{sup -3}. This measurement has the greatest bearing on extensions to the Standard model that incorporate leptoquarks, although exotic fermion and lift-right symmetric models also allow a D as large as the present limit.

  20. Reverse licensing: international technology transfer to the United States

    SciTech Connect (OSTI)

    Sharokhi, M.

    1985-01-01

    This dissertation, theoretically and empirically, focuses on US licensees as the recipient of foreign technology, and investigates characteristics of licensees, licenses, and licensed technology. The viability of reverse licensing, as an international growth strategy, is evaluated from the standpoint of two groups of firms. The first consists of thousands of small and medium sized US manufacturing firms, with few products and virtually no R and D expenditures. Without R and D, new technology and stiff international competition, they are forced into bankruptcies despite their extreme importance in the economy (48% of private workforce, 42% of sales, and 38% of GNP). The second group consists of thousands of small and medium sized firms overseas, with a relatively good supply of technology (i.e., patents) and anxious to exploit the US market but lack required resources for FDI. Technology licensing is, perhaps, the only viable option available to them. Reverse licensing provides both groups with a mechanism for their growth, survival, and prosperity. Many US firms have utilized this strategy for many years (i.e, 118 in Ohio) for tapping foreign sources including Soviet bloc technology.

  1. Semi-Implicit Reversible Algorithms for Rigid Body Rotational Dynamics

    SciTech Connect (OSTI)

    Nukala, Phani K; Shelton Jr, William Allison

    2006-09-01

    This paper presents two semi-implicit algorithms based on splitting methodology for rigid body rotational dynamics. The first algorithm is a variation of partitioned Runge-Kutta (PRK) methodology that can be formulated as a splitting method. The second algorithm is akin to a multiple time stepping scheme and is based on modified Crouch-Grossman (MCG) methodology, which can also be expressed as a splitting algorithm. These algorithms are second-order accurate and time-reversible; however, they are not Poisson integrators, i.e., non-symplectic. These algorithms conserve some of the first integrals of motion, but some others are not conserved; however, the fluctuations in these invariants are bounded over exponentially long time intervals. These algorithms exhibit excellent long-term behavior because of their reversibility property and their (approximate) Poisson structure preserving property. The numerical results indicate that the proposed algorithms exhibit superior performance compared to some of the currently well known algorithms such as the Simo-Wong algorithm, Newmark algorithm, discrete Moser-Veselov algorithm, Lewis-Simo algorithm, and the LIEMID[EA] algorithm.

  2. Fault Diagnosis with Multi-State Alarms in a Nuclear Power Control Simulation

    SciTech Connect (OSTI)

    Stuart A. Ragsdale; Roger Lew; Ronald L. Boring

    2014-09-01

    This research addresses how alarm systems can increase operator performance within nuclear power plant operations. The experiment examined the effects of two types of alarm systems (two-state and three-state alarms) on alarm compliance and diagnosis for two types of faults differing in complexity. We hypothesized the use of three-state alarms would improve performance in alarm recognition and fault diagnoses over that of two-state alarms. Sensitivity and criterion based on the Signal Detection Theory were used to measure performance. We further hypothesized that operator trust would be highest when using three-state alarms. The findings from this research showed participants performed better and had more trust in three-state alarms compared to two-state alarms. Furthermore, these findings have significant theoretical implications and practical applications as they apply to improving the efficiency and effectiveness of nuclear power plant operations.

  3. FAULT DIAGNOSIS WITH MULTI-STATE ALARMS IN A NUCLEAR POWER CONTROL SIMULATOR

    SciTech Connect (OSTI)

    Austin Ragsdale; Roger Lew; Brian P. Dyre; Ronald L. Boring

    2012-10-01

    This research addresses how alarm systems can increase operator performance within nuclear power plant operations. The experiment examined the effect of two types of alarm systems (two-state and three-state alarms) on alarm compliance and diagnosis for two types of faults differing in complexity. We hypothesized three-state alarms would improve performance in alarm recognition and fault diagnoses over that of two-state alarms. We used sensitivity and criterion based on Signal Detection Theory to measure performance. We further hypothesized that operator trust would be highest when using three-state alarms. The findings from this research showed participants performed better and had more trust in three-state alarms compared to two-state alarms. Furthermore, these findings have significant theoretical implications and practical applications as they apply to improving the efficiency and effectiveness of nuclear power plant operations.

  4. Locating hardware faults in a data communications network of a parallel computer

    DOE Patents [OSTI]

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-01-12

    Hardware faults location in a data communications network of a parallel computer. Such a parallel computer includes a plurality of compute nodes and a data communications network that couples the compute nodes for data communications and organizes the compute node as a tree. Locating hardware faults includes identifying a next compute node as a parent node and a root of a parent test tree, identifying for each child compute node of the parent node a child test tree having the child compute node as root, running a same test suite on the parent test tree and each child test tree, and identifying the parent compute node as having a defective link connected from the parent compute node to a child compute node if the test suite fails on the parent test tree and succeeds on all the child test trees.

  5. Gear-box fault detection using time-frequency based methods

    SciTech Connect (OSTI)

    Odgaard, Peter F.; Stoustrup, Jakob

    2015-12-31

    Gear-box fault monitoring and detection is important for optimization of power generation and availability of wind turbines. The current industrial approach is to use condition monitoring systems, which runs in parallel with the wind turbine control system, using expensive additional sensors. An alternative would be to use the existing measurements which are normally available for the wind turbine control system. The usage of these sensors instead would cut down the cost of the wind turbine by not using additional sensors. One of these available measurements is the generator speed, in which changes in the gear-box resonance frequency can be detected. Two different time-frequency based approaches are presented in this paper. One is a filter based approach and the other is based on a Karhunen-Loeve basis. Both of them detects the gear-box fault with an acceptable detection delay.

  6. A dynamical model for condition monitoring and fault diagnostics of spur gears

    SciTech Connect (OSTI)

    Paya, B.; Esat, I.; Badi, M.N.M.

    1996-12-31

    The symptoms of condition monitoring and fault diagnostics of machinery based on the dynamic modelling of spur gears are discussed in this paper. The mathematical model presented in the earlier work, assumes two degree of freedom for each gear and the rotor, and also incorporates a varying gear tooth stiffness. This system is assumed to be in good condition (i.e. no fault present). The results obtained from this analytical model are compared with the ones obtained from an experimental model gearbox. This experimental gearbox consists of two meshing spur gears driven by an electric motor. The comparison of the results are encouraging as fundamental (dominant) frequencies of the analytical results correlates very closely to the experimental ones. It is shown that certain vibration frequency of a real gearbox such as the tooth meshing frequencies can be achieved from its mathematical model.

  7. A microprocessor-based digital feeder monitor with high-impedance fault detection

    SciTech Connect (OSTI)

    Patterson, R.; Tyska, W.; Russell, B.D.

    1994-12-31

    The high impedance fault detection technology developed at Texas A&M University after more than a decade of research, funded in large part by the Electric Power Research Institute, has been incorporated into a comprehensive monitoring device for overhead distribution feeders. This digital feeder monitor (DFM) uses a high waveform sampling rate for the ac current and voltage inputs in conjunction with a high-performance reduced instruction set (RISC) microprocessor to obtain the frequency response required for arcing fault detection and power quality measurements. Expert system techniques are employed to assure security while maintaining dependability. The DFM is intended to be applied at a distribution substation to monitor one feeder. The DFM is packaged in a non-drawout case which fits the panel cutout for a GE IAC overcurrent relay to facilitate retrofits at the majority of sites were electromechanical overcurrent relays already exist.

  8. Methods for locating ground faults and insulation degradation condition in energy conversion systems

    DOE Patents [OSTI]

    Agamy, Mohamed; Elasser, Ahmed; Galbraith, Anthony William; Harfman Todorovic, Maja

    2015-08-11

    Methods for determining a ground fault or insulation degradation condition within energy conversion systems are described. A method for determining a ground fault within an energy conversion system may include, in part, a comparison of baseline waveform of differential current to a waveform of differential current during operation for a plurality of DC current carrying conductors in an energy conversion system. A method for determining insulation degradation within an energy conversion system may include, in part, a comparison of baseline frequency spectra of differential current to a frequency spectra of differential current transient at start-up for a plurality of DC current carrying conductors in an energy conversion system. In one embodiment, the energy conversion system may be a photovoltaic system.

  9. LMFBR fuel-design environment for endurance testing, primarily of oxide fuel elements with local faults

    SciTech Connect (OSTI)

    Warinner, D.K.

    1980-01-01

    The US Department of Energy LMFBR Lines-of-Assurance are briefly stated and local faults are given perspective with an historical review and definition to help define the constraints of LMFBR fuel-element designs. Local-fault-propagation (fuel-element failure-propagation and blockage propagation) perceptions are reviewed. Fuel pin designs and major LMFBR parameters affecting pin performance are summarized. The interpretation of failed-fuel data is aided by a discussion of the effects of nonprototypicalities. The fuel-pin endurance expected in the US, USSR, France, UK, Japan, and West Germany is outlined. Finally, fuel-failure detection and location by delayed-neutron and gaseous-fission-product monitors are briefly discussed to better realize the operational limits.

  10. NREL Research Proves Wind Can Provide Ancillary Grid Fault Response | Grid

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

    Modernization | NREL Research Proves Wind Can Provide Ancillary Grid Fault Response April 1, 2016 Interior of the controllable grid interface test facility, showing a long hallway and shelves full of electronic equipment. The controllable grid interface test facility at the National Wind Technology Center makes it possible to research the effectiveness of wind energy in providing ancillary grid services such as frequency control. Photo by Dennis Schroeder/NREL 27442 Image of a single wind

  11. Fault-Aware Utility-Based Job Scheduling on Blue Gene/P systems | Argonne

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

    Leadership Computing Facility Fault-Aware Utility-Based Job Scheduling on Blue Gene/P systems Authors: Tang, W., Lan, Z., Desai, N., Buettner, D. Job scheduling on large-scale systems is increasingly a complicated affair, with numerous factors influencing scheduling policy. Addressing these concerns results in sophisticated scheduling policies that can be difficult to reason about. In this paper, we present a general utility-based scheduling framework to balance different scheduling

  12. Microsoft Word - GroundFaultSAND-rev7-JJ.doc

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

    3459 Unlimited Release Printed June 2013 Photovoltaic Ground Fault and Blind Spot Electrical Simulations Jack D. Flicker Jay Johnson Prepared by Sandia National Laboratories Albuquerque, New Mexico 87185 and Livermore, California 94550 Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract

  13. The BTeV DAQ and Trigger System - Some throughput, usability and fault tolerance aspects

    SciTech Connect (OSTI)

    Erik Edward Gottschalk et al.

    2001-08-20

    As presented at the last CHEP conference, the BTeV triggering and data collection pose a significant challenge in construction and operation, generating 1.5 Terabytes/second of raw data from over 30 million detector channels. We report on facets of the DAQ and trigger farms. We report on the current design of the DAQ, especially its partitioning features to support commissioning of the detector. We are exploring collaborations with computer science groups experienced in fault tolerant and dynamic real-time and embedded systems to develop a system to provide the extreme flexibility and high availability required of the heterogeneous trigger farm ({approximately} ten thousand DSPs and commodity processors). We describe directions in the following areas: system modeling and analysis using the Model Integrated Computing approach to assist in the creation of domain-specific modeling, analysis, and program synthesis environments for building complex, large-scale computer-based systems; System Configuration Management to include compilable design specifications for configurable hardware components, schedules, and communication maps; Runtime Environment and Hierarchical Fault Detection/Management--a system-wide infrastructure for rapidly detecting, isolating, filtering, and reporting faults which will be encapsulated in intelligent active entities (agents) to run on DSPs, L2/3 processors, and other supporting processors throughout the system.

  14. Sideband Algorithm for Automatic Wind Turbine Gearbox Fault Detection and Diagnosis: Preprint

    SciTech Connect (OSTI)

    Zappala, D.; Tavner, P.; Crabtree, C.; Sheng, S.

    2013-01-01

    Improving the availability of wind turbines (WT) is critical to minimize the cost of wind energy, especially for offshore installations. As gearbox downtime has a significant impact on WT availabilities, the development of reliable and cost-effective gearbox condition monitoring systems (CMS) is of great concern to the wind industry. Timely detection and diagnosis of developing gear defects within a gearbox is an essential part of minimizing unplanned downtime of wind turbines. Monitoring signals from WT gearboxes are highly non-stationary as turbine load and speed vary continuously with time. Time-consuming and costly manual handling of large amounts of monitoring data represent one of the main limitations of most current CMSs, so automated algorithms are required. This paper presents a fault detection algorithm for incorporation into a commercial CMS for automatic gear fault detection and diagnosis. The algorithm allowed the assessment of gear fault severity by tracking progressive tooth gear damage during variable speed and load operating conditions of the test rig. Results show that the proposed technique proves efficient and reliable for detecting gear damage. Once implemented into WT CMSs, this algorithm can automate data interpretation reducing the quantity of information that WT operators must handle.

  15. Geomechanical effects on CO{sub 2} leakage through fault zones during large-scale underground injection

    SciTech Connect (OSTI)

    Rinaldi, A.P.; Rutqvist, J.; Cappa, F.

    2013-09-01

    The importance of geomechanicsincluding the potential for faults to reactivate during large scale geologic carbon sequestration operationshas recently become more widely recognized. However, notwithstanding the potential for triggering notable (felt) seismic events, the potential for buoyancy-driven CO{sub 2} to reach potable groundwater and the ground surface is actually more important from public safety and storage-efficiency perspectives. In this context, this work extends the previous studies on the geomechanical modeling of fault responses during underground carbon dioxide injection, focusing on the short-term integrity of the sealing caprock, and hence on the potential for leakage of either brine or CO{sub 2} to reach the shallow groundwater aquifers during active injection. We consider stress/strain-dependent permeability and study the leakage through the fault zone as its permeability changes during a reactivation, also causing seismicity. We analyze several scenarios related to the volume of CO{sub 2} injected (and hence as a function of the overpressure), involving both minor and major faults, and analyze the profile risks of leakage for different stress/strain-permeability coupling functions. We conclude that whereas it is very difficult to predict how much fault permeability could change upon reactivation, this process can have a significant impact on the leakage rate. Moreover, our analysis shows that induced seismicity associated with fault reactivation may not necessarily open up a new flow path for leakage. Results show a poor correlation between magnitude and amount of fluid leakage, meaning that a single event is generally not enough to substantially change the permeability along the entire fault length. Consequently, even if some changes in permeability occur, this does not mean that the CO{sub 2} will migrate up along the entire fault, breaking through the caprock to enter the overlying aquifer.

  16. Dual capacity compressor with reversible motor and controls arrangement therefor

    DOE Patents [OSTI]

    Sisk, Francis J.

    1980-12-02

    A hermetic reciprocating compressor such as may be used in heat pump applications is provided for dual capacity operation by providing the crankpin of the crankshaft with an eccentric ring rotatably mounted thereon, and with the end of the connecting rod opposite the piston encompassing the outer circumference of the eccentric ring, with means limiting the rotation of the eccentric ring upon the crankpin between one end point and an opposite angularly displaced end point to provide different values of eccentricity depending upon which end point the eccentric ring is rotated to upon the crankpin, and a reversible motor in the hermetic shell of the compressor for rotating the crankshaft, the motor operating in one direction effecting the angular displacement of the eccentric ring relative to the crankpin to the one end point, and in the opposite direction effecting the angular displacement of the eccentric ring relative to the crankpin to the opposite end point, this arrangement automatically giving different stroke lengths depending upon the direction of motor rotation. The mechanical structure of the arrangement may take various forms including at least one in which any impact of reversal is reduced by utilizing lubricant passages and chambers at the interface area of the crankpin and eccentric ring to provide a dashpot effect. In the main intended application of the arrangement according to the invention, that is, in a refrigerating or air conditioning system, it is desirable to insure a delay during reversal of the direction of compressor operation. A control arrangement is provided in which the control system controls the direction of motor operation in accordance with temperature conditions, the system including control means for effecting operation in a low capacity direction or alternatively in a high capacity direction in response to one set, and another set, respectively, of temperature conditions and with timer means delaying a restart of the compressor

  17. Trench logs from a strand of the Rock Valley Fault System, Nevada Test Site, Nye County, Nevada

    SciTech Connect (OSTI)

    Yount, J.C.; Shroba, R.R.; McMasters, C.R.; Huckins, H.E.; Rodriguez, E.A.

    1987-12-31

    The Rock Valley fault system trends northeasterly through the southeast corner of the Nevada Test Site. The system records left-lateral offset of Paleozoic and Tertiary rocks, although total offset amounts to only a few kilometers. Distinct scarps in alluvial deposits of Quaternary age and a concentration of seismicity, particularly at its north end, suggest that the Rock Valley fault system may be active. Two trenches were excavated by backhoe in 1978 across a 0.5-m-high scarp produced by a strand of the Rock Valley fault system. A detailed logging of the two Rock Valley fault trenches was undertaken during the spring of 1984. This report presents: (1) logs of both walls of the two trenches, (2) a general description of the lithologic units and the soils formed in these units that are exposed in and near the fault trenches, (3) observations of the clast fabric of unfaulted and faulted deposits exposed in the trench walls, and (4) a map of the surficial deposits in the vicinity of the trenches.

  18. Reducing collective quantum state rotation errors with reversible dephasing

    SciTech Connect (OSTI)

    Cox, Kevin C.; Norcia, Matthew A.; Weiner, Joshua M.; Bohnet, Justin G.; Thompson, James K.

    2014-12-29

    We demonstrate that reversible dephasing via inhomogeneous broadening can greatly reduce collective quantum state rotation errors, and observe the suppression of rotation errors by more than 21?dB in the context of collective population measurements of the spin states of an ensemble of 2.110{sup 5} laser cooled and trapped {sup 87}Rb atoms. The large reduction in rotation noise enables direct resolution of spin state populations 13(1) dB below the fundamental quantum projection noise limit. Further, the spin state measurement projects the system into an entangled state with 9.5(5) dB of directly observed spectroscopic enhancement (squeezing) relative to the standard quantum limit, whereas no enhancement would have been obtained without the suppression of rotation errors.

  19. Statistical Stability and Time-Reversal Imgaing in Random Media

    SciTech Connect (OSTI)

    Berryman, J; Borcea, L; Papanicolaou, G; Tsogka, C

    2002-02-05

    Localization of targets imbedded in a heterogeneous background medium is a common problem in seismic, ultrasonic, and electromagnetic imaging problems. The best imaging techniques make direct use of the eigenfunctions and eigenvalues of the array response matrix, as recent work on time-reversal acoustics has shown. Of the various imaging functionals studied, one that is representative of a preferred class is a time-domain generalization of MUSIC (MUltiple Signal Classification), which is a well-known linear subspace method normally applied only in the frequency domain. Since statistical stability is not characteristic of the frequency domain, a transform back to the time domain after first diagonalizing the array data in the frequency domain takes optimum advantage of both the time-domain stability and the frequency-domain orthogonality of the relevant eigenfunctions.

  20. Adiabatic model and design of a translating field reversed configuration

    SciTech Connect (OSTI)

    Intrator, T. P.; Siemon, R. E.; Sieck, P. E.

    2008-04-15

    We apply an adiabatic evolution model to predict the behavior of a field reversed configuration (FRC) during decompression and translation, as well as during boundary compression. Semi-empirical scaling laws, which were developed and benchmarked primarily for collisionless FRCs, are expected to remain valid even for the collisional regime of FRX-L experiment. We use this approach to outline the design implications for FRX-L, the high density translated FRC experiment at Los Alamos National Laboratory. A conical theta coil is used to accelerate the FRC to the largest practical velocity so it can enter a mirror bounded compression region, where it must be a suitable target for a magnetized target fusion (MTF) implosion. FRX-L provides the physics basis for the integrated MTF plasma compression experiment at the Shiva-Star pulsed power facility at Kirtland Air Force Research Laboratory, where the FRC will be compressed inside a flux conserving cylindrical shell.

  1. Magnetization reversal driven by a spin torque oscillator

    SciTech Connect (OSTI)

    Sbiaa, R.

    2014-09-01

    Magnetization reversal of a magnetic free layer under spin transfer torque (STT) effect from a magnetic hard layer with a fixed magnetization direction and an oscillating layer is investigated. By including STT from the oscillating layer with in-plane anisotropy and orthogonal polarizer, magnetization-time dependence of free layer is determined. The results show that the frequency and amplitude of oscillations can be varied by adjusting the current density and magnetic properties. For an optimal oscillation frequency (f{sub opt}), a reduction of the switching time (t{sub 0}) of the free layer is observed. Both f{sub opt} and t{sub 0} increase with the anisotropy field of the free layer.

  2. Nanofiltration/reverse osmosis for treatment of coproduced waters

    SciTech Connect (OSTI)

    Mondal, S.; Hsiao, C.L.; Wickramasinghe, S.R. [Colorado State University, Ft Collins, CO (United States)

    2008-07-15

    Current high oil and gas prices have lead to renewed interest in exploration of nonconventional energy sources such as coal bed methane, tar sand, and oil shale. However oil and gas production from these nonconventional sources has lead to the coproduction of large quantities of produced water. While produced water is a waste product from oil and gas exploration it is a very valuable natural resource in the arid Western United States. Thus treated produced water could be a valuable new source of water. Commercially available nanofiltration and low pressure reverse osmosis membranes have been used to treat three produced waters. The results obtained here indicate that the permeate could be put to beneficial uses such as crop and livestock watering. However minimizing membrane fouling will be essential for the development of a practical process. Field Emission Scanning Electron Microscopy imaging may be used to observe membrane fouling.

  3. Anomalous transport theory for the reversed field pinch

    SciTech Connect (OSTI)

    Terry, P.W.; Hegna, C.C; Sovinec, C.R.

    1996-09-01

    Physically motivated transport models with predictive capabilities and significance beyond the reversed field pinch (RFP) are presented. It is shown that the ambipolar constrained electron heat loss observed in MST can be quantitatively modeled by taking account of the clumping in parallel streaming electrons and the resultant self-consistent interaction with collective modes; that the discrete dynamo process is a relaxation oscillation whose dependence on the tearing instability and profile relaxation physics leads to amplitude and period scaling predictions consistent with experiment; that the Lundquist number scaling in relaxed plasmas driven by magnetic turbulence has a weak S{sup {minus}1/4} scaling; and that radial E{times}B shear flow can lead to large reductions in the edge particle flux with little change in the heat flux, as observed in the RFP and tokamak. 24 refs.

  4. Amplification and reversal of Knudsen force by thermoelectric heating

    SciTech Connect (OSTI)

    O'Neill, William J.; Wada, Mizuki; Strongrich, Andrew D.; Cofer, Anthony; Alexeenko, Alina A.

    2014-12-09

    We show that the Knudsen thermal force generated by a thermally-induced flow over a heated beam near a colder wall could be amplified significantly by thermoelectric heating. Bidirectional actuation is achieved by switching the polarity of the thermoelectric device bias voltage. The measurements of the resulting thermal forces at different rarefaction regimes, realized by changing geometry and gas pressure, are done using torsional microbalance. The repulsive or attractive forces between a thermoelectrically heated or cooled plate and a substrate are shown to be up to an order of magnitude larger than for previously studied configurations and heating methods due to favorable coupling of two thermal gradients. The amplification and reversal of the Knudsen force is confirmed by numerical solution of the Boltzmann-ESBGK kinetic model equation. Because of the favorable scaling with decreasing system size, the Knudsen force with thermoelectric heating offers a novel actuation and sensing mechanism for nano/microsystems.

  5. Seismic Reflection Project Near the Southern Terminations of the Lost River and Lemhi Faults, Eastern Snake River Plain, Idaho

    SciTech Connect (OSTI)

    S. M. Jackson; G. S. Carpenter; R. P. Smith; J. L. Casper

    2006-10-01

    Thirteen seismic reflection lines were processed and interpreted to determine the southern terminations of the Lost River and Lemhi faults along the northwest boundary of the eastern Snake River Plain (ESRP). The southernmost terminations of the Arco and Howe segments were determined to support characterization of the Lost River and Lemhi fault sources, respectively, for the INL probabilistic seismic hazard analysis. Keywords:Keywords are required forExternal Release Review*Keywords  Keywords *Contacts (Type and Name are required for each row) Type ofContactContact Name  POC Editor RecordFour commercial seismic reflection lines (Arco lines 81-1 and 81-2; Howe lines 81-3 and 82-2) were obtained from the Montana Power Company. The seismic data were collected in the early 1980’s using a Vibroseis source with station and shot point locations that resulted in 12-fold data. Arco lines 81?1 and 81?2 and Howe lines 81?3 and 82?2 are located within the basins adjacent to the Arco and Howe segments, respectively. Seven seismic lines (Arco lines A1, A2, A3, and A4 and Howe lines H1, H2, and H3) were acquired by EG&G Idaho, Inc. Geosciences for this study using multiple impacts with an accelerated weight drop source. Station and shot point locations yielded 12-fold data. The seismic reflection lines are oriented perpendicular to and at locations along the projected extensions of the Arco and Howe fault segments within the ESRP. Two seismic lines (Arco line S2 and Howe line S4) were obtained from Sierra Geophysics. In 1984, they acquired seismic reflection data using an accelerated weight drop source with station and shot point locations that yielded 6-fold data. The two seismic reflection lines are oriented perpendicular to and at locations along the projected extensions of the Arco and Howe fault segments within the ESRP. In 1992 for this study, Geotrace Technologies Inc. processed all of the seismic reflection data using industry standard processing techniques. The

  6. Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode

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

    Operation with Low Degradation | Department of Energy for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Presented at the Department of Energy Fuel Cell Projects Kickoff Meeting, September 1 - October 1, 2009 petri_versa%20_power_kickoff.pdf (3.53 MB) More Documents & Publications Reversible Fuel Cells Workshop Summary Report Progress on the

  7. Considerations for the use of the modified line reversal technique for gas temperature measurement

    SciTech Connect (OSTI)

    Winkleman, B.C.

    1993-06-01

    Several areas related to the successful and accurate application of modified line reversal are discussed. Initially, generalized modified line reversal equations are developed. A review of basic line reversal theory is presented followed by development of correction factors for optical system effects. Image size and their effect on accurate determinations of spectral radiances is discussed. Temperature biases introduced by image vignetting is calculated. Measured image irradiances are given.

  8. Strong and Reversible Binding of Carbon Dioxide in a Green Metal...

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

    Strong and Reversible Binding of Carbon Dioxide in a Green Metal-Organic Framework Previous Next List Jeremiah J. Gassensmith, Hiroyasu Furukawa, Ronald A. Smaldone, Ross S. ...

  9. Are We Heading Towards a Reversal of the Trend for Ever-Greater...

    Open Energy Info (EERE)

    Mobility? Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Are We Heading Towards a Reversal of the Trend for Ever-Greater Mobility? AgencyCompany Organization:...

  10. Flow reversal power limit for the HFBR (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    The experiments were single channel flow reversal tests under a range of conditions. The analytical phase involved simulations of the tests to benchmark the physical models and ...

  11. Magnetization reversal induced by in-plane current in Ta/CoFeB...

    Office of Scientific and Technical Information (OSTI)

    current are accordance with those for magnetization reversal by spin transfer torque originated from the spin Hall effect in the Ta layer. Authors: Zhang, C. 1 ;...

  12. MODIFIED REVERSE OSMOSIS SYSTEM FOR TREATMENT OF PRODUCED WATERS

    SciTech Connect (OSTI)

    T.M. Whitworth; Liangxiong Li

    2002-09-15

    This report describes work performed during the second year of the project ''Modified reverse osmosis system for treatment of produced waters.'' We performed two series of reverse osmosis experiments using very thin bentonite clay membranes compacted to differing degrees. The first series of 10 experiments used NaCl solutions with membranes that ranged between 0.041 and 0.064mm in thickness. Our results showed compaction of such ultra-thin clay membranes to be problematic. The thickness of the membranes was exceeded by the dimensional variation in the machined experimental cell and this is believed to have resulted in local bypassing of the membrane with a resultant decrease in solute rejection efficiency. In two of the experiments, permeate flow was varied as a percentage of the total flow to investigate results of changing permeate flow on solute rejection. In one experiment, the permeate flow was varied between 2.4 and 10.3% of the total flow with no change in solute rejection. In another experiment, the permeate flow was varied between 24.6 and 52.5% of the total flow. In this experiment, the solute rejection rate decreased as the permeate occupied greater fractions of the total flow. This suggests a maximum solute rejection efficiency for these clay membranes for a permeate flow of between 10.3 and 24.6% of the total; flow. Solute rejection was found to decrease with increasing salt concentration and ranged between 62.9% and 19.7% for chloride and between 61.5 and 16.8% for sodium. Due to problems with the compaction procedure and potential membrane bypassing, these rejection rates are probably not the upper limit for NaCl rejection by bentonite membranes. The second series of four reverse osmosis experiments was conducted with a 0.057mm-thick bentonite membrane and dilutions of a produced water sample with an original TDS of 196,250 mg/l obtained from a facility near Loco Hill, New Mexico, operated by an independent. These experiments tested the separation

  13. MODIFIED REVERSE OSMOSIS SYSTEM FOR TREATMENT OF PRODUCED WATERS

    SciTech Connect (OSTI)

    T.M. Whitworth; Liangxiong Li

    2002-09-15

    This report describes work performed during the first year of the project ''Modified Reverse Osmosis System for Treatment of Produced Waters.'' This research project has two objectives. The first objective is to test the use of clay membranes in the treatment of produced waters by reverse osmosis. The second objective is to test the ability of a system patented by the New Mexico Tech Research Foundation to remove salts from reverse osmosis waste streams as a solid. We performed 12 experiments using clay membranes in cross-flow experimental cells. We found that, due to dispersion in the porous frit used adjacent to the membrane, the concentration polarization layer seems to be completely (or nearly completely) destroyed at low flow rates. This observation suggests that clay membranes used with porous frit material many reach optimum rejection rates at lower pumping rates than required for use with synthetic membranes. The solute rejection efficiency decreases with increasing solution concentration. For the membranes and experiments reported here, the rejection efficiency ranged from 71% with 0.01 M NaCl solution down to 12% with 2.3 M NaCl solution. More compacted clay membranes will have higher rejection capabilities. The clay membranes used in our experiments were relatively thick (approximately 0.5 mm). The active layer of most synthetic membranes is only 0.04 {micro}m (0.00004 mm), approximately 1250 times thinner than the clay membranes used in these experiments. Yet clay membranes as thin as 12 {micro}m have been constructed (Fritz and Eady, 1985). Since Darcy's law states that the flow through a material of constant permeability is inversely proportional to it's the material's thickness, then, based on these experimental observations, a very thin clay membrane would be expected to have much higher flow rates than the ones used in these experiments. Future experiments will focus on testing very thin clay membranes. The membranes generally exhibited reasonable

  14. High energy arcing fault fires in switchgear equipment : a literature review.

    SciTech Connect (OSTI)

    Nowlen, Steven Patrick; Brown, Jason W.; Wyant, Francis John

    2008-10-01

    In power generating plants, switchgear provide a means to isolate and de-energize specific electrical components and buses in order to clear downstream faults, perform routine maintenance, and replace necessary electrical equipment. These protective devices may be categorized by the insulating medium, such as air or oil, and are typically specified by voltage classes, i.e. low, medium, and high voltage. Given their high energy content, catastrophic failure of switchgear by means of a high energy arcing fault (HEAF) may occur. An incident such as this may lead to an explosion and fire within the switchgear, directly impact adjacent components, and possibly render dependent electrical equipment inoperable. Historically, HEAF events have been poorly documented and discussed in little detail. Recent incidents involving switchgear components at nuclear power plants, however, were scrupulously investigated. The phenomena itself is only understood on a very elementary level from preliminary experiments and theories; though many have argued that these early experiments were inaccurate due to primitive instrumentation or poorly justified methodologies and thus require re-evaluation. Within the past two decades, however, there has been a resurgence of research that analyzes previous work and modern technology. Developing a greater understanding of the HEAF phenomena, in particular the affects on switchgear equipment and other associated switching components, would allow power generating industries to minimize and possibly prevent future occurrences, thereby reducing costs associated with repair and downtime. This report presents the findings of a literature review focused on arc fault studies for electrical switching equipment. The specific objective of this review was to assess the availability of the types of information needed to support development of improved treatment methods in fire Probabilistic Risk Assessment (PRA) for nuclear power plant applications.

  15. Earthquake geology of the northern San Andreas Fault near Point Arena, California

    SciTech Connect (OSTI)

    Prentice, C.S.

    1989-01-01

    Excavations into a Holocene alluvial fan provided exposures of a record of prehistoric earthquakes near Point Arena, California. At least five earthquakes were recognized in the section. All of these occurred since the deposition of a unit that is approximately 2000 years old. Radiocarbon dating allows constraints to be placed on the dates of these earthquakes. A buried Holocene (2356-2709 years old) channel has been offset a maximum of 64 {plus minus} 2 meters. This implies a maximum slip rate of 25.5 {plus minus} 2.5 mm/yr. These data suggest that the average recurrence interval for great earthquakes on this segment of the San Andreas fault is long - between about 200 and 400 years. Offset marine terrace risers near Point Arena and an offset landslide near Fort Ross provide estimates of the average slip rate since Late Pleistocene time. Near Fort Ross, an offset landslide implies a slip rate of less than 39 mm/yr. Correlation and age estimates of two marine terrace risers across the San Andreas fault near Point Arena suggest slip rates of about 18-19 mm/yr since Late Pleistocene time. Tentative correlation of the Pliocene Ohlson Ranch Formation in northwestern Sonoma County with deposits 50 km to the northwest near Point Arean, provides piercing points to use in calculation of a Pliocene slip rate for the northern San Andreas fault. A fission-track age 3.3 {plus minus} 0.8 Ma was determined for zicrons separated from a tuff collected from the Ohlson Ranch Formation. The geomorphology of the region, especially of the two major river drainages, supports the proposed 50 km Pliocene offset. This implies a Pliocene slip rate of at least 12-20 mm/yr. These rates for different time periods imply that much of the Pacific-North American plate motion must be accommodated on other structures at this latitude.

  16. Reversible rigid coupling apparatus and method for borehole seismic transducers

    DOE Patents [OSTI]

    Owen, Thomas E.; Parra, Jorge O.

    1992-01-01

    An apparatus and method of high resolution reverse vertical seismic profile (VSP) measurements is shown. By encapsulating the seismic detector and heaters in a meltable substance (such as wax), the seismic detector can be removably secured in a borehole in a manner capable of measuring high resolution signals in the 100 to 1000 hertz range and higher. The meltable substance is selected to match the overall density of the detector package with the underground formation, yet still have relatively low melting point and rigid enough to transmit vibrations to accelerometers in the seismic detector. To minimize voids in the meltable substance upon solidification, the meltable substance is selected for minimum shrinkage, yet still having the other desirable characteristics. Heaters are arranged in the meltable substance in such a manner to allow the lowermost portion of the meltable substance to cool and solidify first. Solidification continues upwards from bottom-to-top until the top of the meltable substance is solidified and the seismic detector is ready for use. To remove, the heaters melt the meltable substance and the detector package is pulled from the borehole.

  17. Compact Reversed-Field Pinch Reactors (CRFPR): preliminary engineering considerations

    SciTech Connect (OSTI)

    Hagenson, R.L.; Krakowski, R.A.; Bathke, C.G.; Miller, R.L.; Embrechts, M.J.; Schnurr, N.M.; Battat, M.E.; LaBauve, R.J.; Davidson, J.W.

    1984-08-01

    The unique confinement physics of the Reversed-Field Pinch (RFP) projects to a compact, high-power-density fusion reactor that promises a significant reduction in the cost of electricity. The compact reactor also promises a factor-of-two reduction in the fraction of total cost devoted to the reactor plant equipment (i.e., fusion power core (FPC) plus support systems). In addition to operational and developmental benefits, these physically smaller systems can operate economically over a range of total power output. After giving an extended background and rationale for the compact fusion approaches, key FPC subsystems for the Compact RFP Reactor (CRFPR) are developed, designed, and integrated for a minimum-cost, 1000-MWe(net) system. Both the problems and promise of the compact, high-power-density fusion reactor are quantitatively evaluated on the basis of this conceptual design. The material presented in this report both forms a framework for a broader, more expanded conceptual design as well as suggests directions and emphases for related research and development.

  18. Turbulent transport in the MST reversed-field pinch

    SciTech Connect (OSTI)

    Rempel, T.D.; Almagri, A.F.; Assadi, S.; Den Hartog, D.J.; Hokin, S.A.; Prager, S.C.; Sarff, J.S.; Shen, W.; Sidikman, K.L.; Spragins, C.W.; Sprott, J.C.; Stoneking, M.R.; Zita, E.J.

    1991-11-01

    Measurements of edge turbulence and the associated transport are ongoing in the Madison Symmetric Torus (R = 1.5 m, a = 0.52 m) reversed-field pinch using magnetic and electrostatic probes. Magnetic fluctuations are dominated by m = 1 and n {approximately} 2R/a tearing modes. Particle losses induced by magnetic field fluctuations have been found to be ambipolar (<{tilde J}{sub parallel}{tilde B}{sub r}> = O). Electrostatic fluctuations are broadband and turbulent, with mode widths {delta}m {approximately} 3--7 and {delta}n {approximately}70--150. Particle, parallel current, and energy transport arising from coherent motion with the fluctuating {tilde E}xB drift has been measured. Particle transport via this channel is comparable to the total particle loss from MST. Energy transport (from <{tilde P}{tilde E}{sub phi}>/B{sub o}) due to electrostatic fluctuations is relatively small, and parallel current transport (from <{tilde J}{sub parallel}{tilde E}{sub chi}>/B{sub o}) may be small as well.

  19. Transport and equilibrium in field-reversed mirrors

    SciTech Connect (OSTI)

    Boyd, J.K.

    1982-09-01

    Two plasma models relevant to compact torus research have been developed to study transport and equilibrium in field reversed mirrors. In the first model for small Larmor radius and large collision frequency, the plasma is described as an adiabatic hydromagnetic fluid. In the second model for large Larmor radius and small collision frequency, a kinetic theory description has been developed. Various aspects of the two models have been studied in five computer codes ADB, AV, NEO, OHK, RES. The ADB code computes two dimensional equilibrium and one dimensional transport in a flux coordinate. The AV code calculates orbit average integrals in a harmonic oscillator potential. The NEO code follows particle trajectories in a Hill's vortex magnetic field to study stochasticity, invariants of the motion, and orbit average formulas. The OHK code displays analytic psi(r), B/sub Z/(r), phi(r), E/sub r/(r) formulas developed for the kinetic theory description. The RES code calculates resonance curves to consider overlap regions relevant to stochastic orbit behavior.

  20. Fusion proton diagnostic for the C-2 field reversed configuration

    SciTech Connect (OSTI)

    Magee, R. M. Clary, R.; Korepanov, S.; Smirnov, A.; Garate, E.; Knapp, K.; Tkachev, A.

    2014-11-15

    Measurements of the flux of fusion products from high temperature plasmas provide valuable insights into the ion energy distribution, as the fusion reaction rate is a very sensitive function of ion energy. In C-2, where field reversed configuration plasmas are formed by the collision of two compact toroids and partially sustained by high power neutral beam injection [M. Binderbauer et al., Phys. Rev. Lett. 105, 045003 (2010); M. Tuszewski et al., Phys. Rev. Lett. 108, 255008 (2012)], measurements of DD fusion neutron flux are used to diagnose ion temperature and study fast ion confinement and dynamics. In this paper, we will describe the development of a new 3 MeV proton detector that will complement existing neutron detectors. The detector is a large area (50?cm{sup 2}), partially depleted, ion implanted silicon diode operated in a pulse counting regime. While the scintillator-based neutron detectors allow for high time resolution measurements (?100 kHz), they have no spatial or energy resolution. The proton detector will provide 10 cm spatial resolution, allowing us to determine if the axial distribution of fast ions is consistent with classical fast ion theory or whether anomalous scattering mechanisms are active. We will describe in detail the diagnostic design and present initial data from a neutral beam test chamber.

  1. Treatment of biomass gasification wastewaters using reverse osmosis

    SciTech Connect (OSTI)

    Petty, S.E.; Eliason, S.D.; Laegreid, M.M.

    1981-09-01

    Reverse osmosis (RO) was evaluated as a treatment technology for the removal of organics from biomass gasification wastewaters (BGW) generated from an experimental biomass gasifier at Texas Tech University. Wastewaters were characteristically high in chemical oxygen demand (COD) with initial values ranging from 32,000 to 68,000 mg/1. Since RO is normally considered a complementary treatment technology, wastewaters were pretreated by biological or wet air oxidation (WAO) processes. One set of experiments were run using untreated wastewaters to compare membrane performance with those experiments using pretreated wastewaters. Experiments were run for 8 to 10 hrs using UOP's TFC-85 membrane operating at 700 psig and 18 to 20/sup 0/C. This membrane is similar to the NS-100, a membrane known for being effective in the separation of organics from solution. Separation of organics from solution was determined by COD removal. Removal percentages for biologically pretreated wastewaters averaged 98% except for one group of runs averaging 69% removal. This exception was probably due to the presence of milk solids in the feed. Use of RO on WAO pretreated wastewaters and unpretreated feeds resulted in 90% COD removal. Membrane degradation was observed when using full-strength and WAO pretreated feeds, but not when using feeds that had undergone biological pretreatment. Color removal was computed for the majority of experiments completed. Overall, 99 to 100% of the total color was removed from BGW feeds, values which coincide with those reported in the literature for other wastewaters.

  2. Two-dimensional interpreter for field-reversed configurations

    SciTech Connect (OSTI)

    Steinhauer, Loren

    2014-08-15

    An interpretive method is developed for extracting details of the fully two-dimensional (2D) “internal” structure of field-reversed configurations (FRC) from common diagnostics. The challenge is that only external and “gross” diagnostics are routinely available in FRC experiments. Inferring such critical quantities as the poloidal flux and the particle inventory has commonly relied on a theoretical construct based on a quasi-one-dimensional approximation. Such inferences sometimes differ markedly from the more accurate, fully 2D reconstructions of equilibria. An interpreter based on a fully 2D reconstruction is needed to enable realistic within-the-shot tracking of evolving equilibrium properties. Presented here is a flexible equilibrium reconstruction with which an extensive data base of equilibria was constructed. An automated interpreter then uses this data base as a look-up table to extract evolving properties. This tool is applied to data from the FRC facility at Tri Alpha Energy. It yields surprising results at several points, such as the inferences that the local β (plasma pressure/external magnetic pressure) of the plasma climbs well above unity and the poloidal flux loss time is somewhat longer than previously thought, both of which arise from full two-dimensionality of FRCs.

  3. Multichannel optical diagnostic system for field-reversed configuration plasmas

    SciTech Connect (OSTI)

    Takahashi, Tsutomu; Gota, Hiroshi; Fujino, Toshiyuki; Okada, Masanori; Asai, Tomohiko; Fujimoto, Kayoko; Ohkuma, Yasunori; Nogi, Yasuyuki

    2004-12-01

    A constructed diagnostic system consisting of a 60-channel set of optical detectors with flexible viewing configurations is realized to investigate three-dimensional magnetohydrodynamic (MHD) motions and the internal structure of a field-reversed configuration (FRC) plasma. The system can detect radiation from the plasma in the wavelength range of 420-820 nm. Optical filters are used to select the wavelength ranges required in the experiment. The sensitivities of all the optical detectors are calibrated using radiation from the FRC plasma at a quiescent phase. Radiation profiles measured by orthogonal viewing configuration of the detectors are shown at three toroidal cross sections. From these profiles, the time evolution of the three-dimensional MHD motion of the plasma is depicted. The radiation profile measured by a one-dimensional viewing configuration yields not only an electron density profile inside the separatrix but also the width of an edge-layer plasma. A bright halo around the edge-layer plasma is observed using a Balmer-{alpha} line filter. The orthogonal viewing configuration can also be used to analyze the internal structure of the FRC. The deviated position of the major axis is estimated from the comparison between the measured radiation profiles and the nonconcentric density profile based on the rigid rotor profile model.

  4. Advances in the numerical modeling of field-reversed configurations

    SciTech Connect (OSTI)

    Belova, Elena V.; Davidson, Ronald C.; Ji, Hantao; Yamada, Masaaki

    2006-05-15

    The field-reversed configuration (FRC) is a compact torus with little or no toroidal magnetic field. A theoretical understanding of the observed FRC equilibrium and stability properties presents significant challenges due to the high plasma beta, plasma flows, large ion gyroradius, and the stochasticity of the particle orbits. Advanced numerical simulations are generally required to describe and understand the detailed behavior of FRC plasmas. Results of such simulations are presented in this paper. It is shown that 3D nonlinear hybrid simulations using the HYM code [E. V. Belova et al., Phys. Plasmas 7, 4996 (2000)] reproduce all major experimentally observed stability properties of elongated (theta-pinch-formed) FRCs. Namely, the scaling of the growth rate of the n=1 tilt mode with the S*/E parameter (S* is the FRC kinetic parameter, E is elongation, and n is toroidal mode number), the nonlinear saturation of the tilt mode, ion toroidal spin-up, and the growth of the n=2 rotational mode have been demonstrated and studied in detail. The HYM code has also been used to study stability properties of FRCs formed by the counterhelicity spheromak merging method. A new stability regime has been found for FRCs with elongation E{approx}1, which requires a close-fitting conducting shell and energetic beam ion stabilization.

  5. Two-fluid physics and field-reversed configurations

    SciTech Connect (OSTI)

    Hakim, A.; Shumlak, U.

    2007-05-15

    In this paper, algorithms for the solution of two-fluid plasma equations are presented and applied to the study of field-reversed configurations (FRCs). The two-fluid model is more general than the often used magnetohydrodynamic (MHD) model. The model takes into account electron inertia, charge separation, and the full electromagnetic field equations, and it allows for separate electron and ion motion. The algorithm presented is the high-resolution wave propagation scheme. The wave propagation method is based on solutions to the Riemann problem at cell interfaces. Operator splitting is used to incorporate the Lorentz and electromagnetic source terms. The algorithms are benchmarked against the Geospace Environmental Modeling Reconnection Challenge problem. Equilibrium of FRC is studied. It is shown that starting from a MHD equilibrium produces a relaxed two-fluid equilibrium with strong flows at the FRC edges due to diamagnetic drift. The azimuthal electron flow causes lower-hybrid drift instabilities (LHDI), which can be captured if the ion gyroradius is well resolved. The LHDI is known to be a possible source of anomalous resistivity in many plasma configurations. LHDI simulations are performed in slab geometries and are compared to recent experimental results.

  6. Homopolar machine for reversible energy storage and transfer systems

    DOE Patents [OSTI]

    Stillwagon, Roy E.

    1978-01-01

    A homopolar machine designed to operate as a generator and motor in reversibly storing and transferring energy between the machine and a magnetic load coil for a thermo-nuclear reactor. The machine rotor comprises hollow thin-walled cylinders or sleeves which form the basis of the system by utilizing substantially all of the rotor mass as a conductor thus making it possible to transfer substantially all the rotor kinetic energy electrically to the load coil in a highly economical and efficient manner. The rotor is divided into multiple separate cylinders or sleeves of modular design, connected in series and arranged to rotate in opposite directions but maintain the supply of current in a single direction to the machine terminals. A stator concentrically disposed around the sleeves consists of a hollow cylinder having a number of excitation coils each located radially outward from the ends of adjacent sleeves. Current collected at an end of each sleeve by sleeve slip rings and brushes is transferred through terminals to the magnetic load coil. Thereafter, electrical energy returned from the coil then flows through the machine which causes the sleeves to motor up to the desired speed in preparation for repetition of the cycle. To eliminate drag on the rotor between current pulses, the brush rigging is designed to lift brushes from all slip rings in the machine.

  7. Reversed-field pinch studies in the Madison Symmetric Torus

    SciTech Connect (OSTI)

    Hokin, S.; Almagri, A.; Cekic, M.; Chapman, B.; Crocker, N.; Den Hartog, D.J.; Fiksel, G.; Henry, J.; Ji, H.; Prager, S.; Sarff, J.; Scime, E.; Shen, W.; Stoneking, M.; Watts, C.

    1993-04-03

    Studies of large-size (R = 1.5 m, a = 0.5 m), moderate current (I < 750 kA) reversed-field pinch (RFP) plasmas are carried out in the Madison Symmetric Torus in order to evaluate and improve RFP confinement, study general toroidal plasma MHD issues, determine the mechanism of the RFP dynamo, and measure fluctuation-induced transport and anomalous ion heating. MST confinement has been improved by reduction of magnetic field errors with correction coils in the primary circuit and reduction of impurities using boronization; high densities have been achieved with hydrogen pellet injection. MHD tearing modes with poloidal mode number m = 1 and toroidal mode numbers n = 5--7 are prevalent and nonlinearly couple to produce sudden relaxations akin to tokamak sawteeth. Edge fluctuation-induced transport has been measured with a variety of insertable probes. Ions exhibit anomalous heating, with increases of ion temperature occuring during strong MHD relaxation. The RFP dynamo has been studied with attention to various possible mechanisms, including motion-EMF drive, the Hall effect, and superthermal electrons. Initial profile control experiments have begun using insertable biased probes and plasma guns. The toroidal field capacity of MST will be upgraded during Summer, 1993 to allow low-current tokamak operation as well as improved RFP operation.

  8. Homopolar machine for reversible energy storage and transfer systems

    DOE Patents [OSTI]

    Stillwagon, Roy E.

    1981-01-01

    A homopolar machine designed to operate as a generator and motor in reversibly storing and transferring energy between the machine and a magnetic load coil for a thermo-nuclear reactor. The machine rotor comprises hollow thin-walled cylinders or sleeves which form the basis of the system by utilizing substantially all of the rotor mass as a conductor thus making it possible to transfer substantially all the rotor kinetic energy electrically to the load coil in a highly economical and efficient manner. The rotor is divided into multiple separate cylinders or sleeves of modular design, connected in series and arranged to rotate in opposite directions but maintain the supply of current in a single direction to the machine terminals. A stator concentrically disposed around the sleeves consists of a hollow cylinder having a number of excitation coils each located radially outward from the ends of adjacent sleeves. Current collected at an end of each sleeve by sleeve slip rings and brushes is transferred through terminals to the magnetic load coil. Thereafter, electrical energy returned from the coil then flows through the machine which causes the sleeves to motor up to the desired speed in preparation for repetition of the cycle. To eliminate drag on the rotor between current pulses, the brush rigging is designed to lift brushes from all slip rings in the machine.

  9. Low Cost Arc Fault Detection and Protection for PV Systems: January 30, 2012 - September 30, 2013

    SciTech Connect (OSTI)

    McCalmont, S.

    2013-10-01

    Final report for Tigo Energy Incubator project. The specific objective of this 18-month research effort was to develop an off-the-shelf arc-fault detector. The starting point of the project was a prototype detector that was constructed using discrete components and laboratory equipment. An intermediate objective was to build a technically viable detector using programmable components in the detector circuitry. The final objective was to build a commercially viable detector by reducing the cost of the circuitry through the use of more sophisticated programmable components and higher levels of integration.

  10. Composite refraction-reflection stack sections: Tracing faults in the Atlantic coastal plain sediments

    SciTech Connect (OSTI)

    Stephenson, D.E.; Coruh, C.; Costain, J.K.

    1993-05-01

    Seismic data from the Atlantic Coastal Plain are reprocessed and composite refraction-reflection stack sections produced to investigate basement faults that penetrate upward into Atlantic Coastal Plain sediments in South Carolina. Reprocessing recovered reflections from within the deep crust to the Moho as well as from within thin veneer (300) of the Atlantic Coastal Plain sediments. One of the major objectives of this paper is to discuss the use of shallow refracted arrivals to construct a composite refraction- reflection stack that allows better imaging of the subsurface at shallow depths.

  11. Hydrologic characterization of faults and other potentially conductive geologic features in the unsaturated zone

    SciTech Connect (OSTI)

    Javandel, I.; Shan, C.

    1990-01-01

    The capability of characterizing near-vertical faults and other potentially highly conductive geologic features in the vicinity of a high-level-waste repository is of great importance in site characterization of underground waste-isolation projects. The possibility of using transient air pressure data at depth for characterizing these features in the unsaturated zone are investigated. Analytical solutions for calculating the pressure response of such systems are presented. Solutions are given for two types of barometric pressure fluctuations, step function and sinusoidal. 3 refs., 9 figs.

  12. Formation and Growth of Stacking Fault Tetrahedra in Ni via Vacancy Aggregation Mechanism

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

    Aidhy, Dilpuneet S.; Lu, Chenyang; Jin, Ke; Bei, Hongbin; Zhang, Yanwen; Wang, Lumin; Weber, William J.

    2015-12-29

    Using molecular dynamics simulations, the formation and growth of stacking fault tetrahedra (SFT) are captured by vacancy cluster diffusion and aggregation mechanisms in Ni. The vacancytetrahedron acts as a nucleation point for SFT formation. Simulations show that perfect SFT can grow to the next size perfect SFT via a vacancy aggregation mechanism. The stopping and range of ions in matter (SRIM) calculations and transmission electron microscopy (TEM) observations reveal that SFT can form farther away from the initial cascade-event locations, indicating the operation of diffusion-based vacancy-aggregation mechanism.

  13. NO FAULT

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

    does it again! Thursday, December 18, 2014 - 2:23pm Employees donate bikes, toys, time, cash for Toys for Tots Employees at the Nevada National Security Site have outdone themselves again this year by collecting 123 bicycles and 17 barrels of toys for this year's Toys for Tots campaign. The items will be distributed to children in the Las Vegas, Nev., area. Last year the Marine Corps fulfilled the holiday hopes and dreams of 6.8 million less fortunate children in 762 communities nationwide.

  14. Some Results Bearing on the Value of Improvements of Membranes for Reverse Osmosis

    SciTech Connect (OSTI)

    Lamont, A

    2006-03-08

    This analysis evaluates the potential economic benefits that could result from the improvements in the permeability of membranes for reverse osmosis. The discussion provides a simple model of the operation of a reverse osmosis plant. It examines the change in the operation that might result from improvements in the membrane and computes the cost of water as a function of the membrane permeability.

  15. Electric Dipole Moments in Radioactive Nuclei, Tests of Time Reversal Symmetry

    SciTech Connect (OSTI)

    Auerbach, N.

    2010-11-24

    The research of radioactive nuclei opens new possibilities to study fundamental symmetries, such as time reversal and reflection symmetry. Such nuclei often provide conditions to check in an optimal way certain symmetries and the violation of such symmetries. We will discuss the possibility of obtaining improved limits on violation of time reversal symmetry using pear shaped radioactive nuclei. An effective method to test time reversal invariance in the non-strange sector is to measure parity and time reversal violating (T-P-odd) electromagnetic moments, (such as the static electric dipole moment). Parity and time reversal violating components in the nuclear force may produce P-T-odd moments in nuclei which in turn induce such moments in atoms. We will discuss the possibility that in some reflection asymmetric, heavy nuclei (which are radioactive) these moments are enhanced by several orders of magnitude. Present and future experiments, which will test this idea, will be mentioned.

  16. Radiative reverse shock laser experiments relevant to accretion processes in cataclysmic variables

    SciTech Connect (OSTI)

    Krauland, C. M.; Drake, R. P.; Kuranz, C. C.; Sweeney, R.; Grosskopf, M.; Klein, S.; Gillespie, R.; Keiter, P. A.; Loupias, B.; Falize, E.

    2013-05-15

    We discuss the production of radiative reverse shocks in experiments at the Omega-60 laser facility. The ability of this high-intensity laser to impart large energy densities on micron-thin foils makes it feasible to create supersonic plasma flows. Obtaining a radiative reverse shock in the laboratory requires a sufficiently fast flow (∼100 km/s) of a material whose opacity is large enough to produce energetically significant emission from experimentally achievable shocked layers. The reverse shock forms in the flow once it is impeded. This paper presents the first radiographic data of normal incidence, reverse shockwaves. These experiments are primarily motivated by the contribution of radiative reverse shock waves to the evolving dynamics of the cataclysmic variable (CV) system in which they reside. We show similarity properties to suggest that the experimental production of radiative reserve shocks in the laboratory may be scalable to such astrophysical systems.

  17. Petrogenesis of the reversely-zoned Turtle pluton, southeastern California

    SciTech Connect (OSTI)

    Allen, C.M.

    1989-01-01

    Few plutons with a reversed geometry of a felsic rim and mafic core have been described in the geologic literature. The Turtle pluton of S.E. California is an intrusion composed of a granitic rim and granodioritic core and common microgranitoid enclaves. Field observations, mineral textures and chemistries, major and trace element geochemistry, and isotopic variability support a petrogenetic model of in situ, concomitant, magma mixing and fractional crystallization of rhyolitic magma progressively mixed with an increasing volume of andesitic magma, all without chemical contribution from entrained basaltic enclaves. Hornblende geobarometry indicates the Turtle pluton crystallized at about 3.5 kb. A crystallization sequence of biotite before hornblende (and lack of pyroxenes) suggests the initial granitic magma contained less than 4 wt% H{sub 2}O at temperatures less than 780C. U-Pb, Pb-Pb, Rb-Sr and oxygen isotope studies indicate the terrane intruded by the Turtle pluton is 1.8 Ga, that the Turtle pluton crystallized at 130 Ma, that the Target Granite and garnet aplites are about 100 Ma, and that these intrusions were derived from different sources. Models based on isotopic data suggest the rhyolitic end member magma of the Turtle pluton was derived from mafic igneous rocks, and was not derived from sampled Proterozoic country rocks. Similarity of common Sr and Pb isotopic ratios of these rocks to other Mesozoic intrusions in the Colorado River Region suggest the Turtle pluton and Target Granite have affinities like rocks to the east, including the Whipple Mountains and plutons of western Arizona. P-T-t history of the southern Turtle Mountains implies uplift well into the upper crust by Late Cretaceous time so that the heating and deformation events of the Late Cretaceous and Tertiary observed in flanking ranges did not affect the study area.

  18. The TITAN Reversed-Field Pinch fusion reactor study

    SciTech Connect (OSTI)

    Not Available

    1988-03-01

    The TITAN Reversed-Field Pinch (RFP) fusion reactor study is a multi-institutional research effort to determine the technical feasibility and key developmental issues of an RFP fusion reactor, especially at high power density, and to determine the potential economics, operations, safety, and environmental features of high-mass-power-density fusion systems. The TITAN conceptual designs are DT burning, 1000 MWe power reactors based on the RFP confinement concept. The designs are compact, have a high neutron wall loading of 18 MW/m{sup 2} and a mass power density of 700 kWe/tonne. The inherent characteristics of the RFP confinement concept make fusion reactors with such a high mass power density possible. Two different detailed designs have emerged: the TITAN-I lithium-vanadium design, incorporating the integrated-blanket-coil concept; and the TITAN-II aqueous loop-in-pool design with ferritic steel structure. This report contains a collection of 16 papers on the results of the TITAN study which were presented at the International Symposium on Fusion Nuclear Technology. This collection describes the TITAN research effort, and specifically the TITAN-I and TITAN-II designs, summarizing the major results, the key technical issues, and the central conclusions and recommendations. Overall, the basic conclusions are that high-mass power-density fusion reactors appear to be technically feasible even with neutron wall loadings up to 20 MW/m{sup 2}; that single-piece maintenance of the FPC is possible and advantageous; that the economics of the reactor is enhanced by its compactness; and the safety and environmental features need not to be sacrificed in high-power-density designs. The fact that two design approaches have emerged, and others may also be possible, in some sense indicates the robustness of the general findings.

  19. Faults and gravity anomalies over the East Mesa hydrothermal-geothermal system

    SciTech Connect (OSTI)

    Goldstein, N.E.; Carle, S.

    1986-05-01

    Detailed interpretations of gravity anomalies over geothermal systems may be extremely useful for mapping the fracture or fault systems that control the circulation of the thermal waters. This approach seems to be particularly applicable in areas like the Salton Trough where reactions between the thermal waters and the porous sediments produce authigenic-hydrothermal minerals in sufficient quantity to cause distinct gravity anomalies at the surface. A 3-D inversion of the residual Bouguer gravity anomaly over the East Mesa geothermal field was made to examine the densified volume of rock. We show that the data not only resolve a north-south and an intersecting northwest structure, but that it may be possible to distinguish between the active present-day hydrothermal system and an older and cooler part of the system. The densified region is compared spatially to self-potential, thermal and seismic results and we find a good concordance between the different geophysical data sets. Our results agree with previous studies that have indicated that the main feeder fault recharging the East Mesa reservoir dips steeply to the west.

  20. Insights From Laboratory Experiments On Simulated Faults With Application To Fracture Evolution In Geothermal Systems

    SciTech Connect (OSTI)

    Stephen L. Karner, Ph.D

    2006-06-01

    Laboratory experiments provide a wealth of information related to mechanics of fracture initiation, fracture propagation processes, factors influencing fault strength, and spatio-temporal evolution of fracture properties. Much of the existing literature reports on laboratory studies involving a coupling of thermal, hydraulic, mechanical, and/or chemical processes. As these processes operate within subsurface environments exploited for their energy resource, laboratory results provide insights into factors influencing the mechanical and hydraulic properties of geothermal systems. I report on laboratory observations of strength and fluid transport properties during deformation of simulated faults. The results show systematic trends that vary with stress state, deformation rate, thermal conditions, fluid content, and rock composition. When related to geophysical and geologic measurements obtained from engineered geothermal systems (e.g. microseismicity, wellbore studies, tracer analysis), laboratory results provide a means by which the evolving thermal reservoir can be interpreted in terms of physico-chemical processes. For example, estimates of energy release and microearthquake locations from seismic moment tensor analysis can be related to strength variations observed from friction experiments. Such correlations between laboratory and field data allow for better interpretations about the evolving mechanical and fluid transport properties in the geothermal reservoir ultimately leading to improvements in managing the resource.

  1. Creating dynamic equivalent PV circuit models with impedance spectroscopy for arc-fault modeling.

    SciTech Connect (OSTI)

    Johnson, Jay Dean; Kuszmaul, Scott S.; Strauch, Jason E.; Schoenwald, David Alan

    2011-06-01

    Article 690.11 in the 2011 National Electrical Code{reg_sign} (NEC{reg_sign}) requires new photovoltaic (PV) systems on or penetrating a building to include a listed arc fault protection device. Currently there is little experimental or empirical research into the behavior of the arcing frequencies through PV components despite the potential for modules and other PV components to filter or attenuate arcing signatures that could render the arc detector ineffective. To model AC arcing signal propagation along PV strings, the well-studied DC diode models were found to inadequately capture the behavior of high frequency arcing signals. Instead dynamic equivalent circuit models of PV modules were required to describe the impedance for alternating currents in modules. The nonlinearities present in PV cells resulting from irradiance, temperature, frequency, and bias voltage variations make modeling these systems challenging. Linearized dynamic equivalent circuits were created for multiple PV module manufacturers and module technologies. The equivalent resistances and capacitances for the modules were determined using impedance spectroscopy with no bias voltage and no irradiance. The equivalent circuit model was employed to evaluate modules having irradiance conditions that could not be measured directly with the instrumentation. Although there was a wide range of circuit component values, the complex impedance model does not predict filtering of arc fault frequencies in PV strings for any irradiance level. Experimental results with no irradiance agree with the model and show nearly no attenuation for 1 Hz to 100 kHz input frequencies.

  2. Evaluation of Simple Causal Message Logging for Large-Scale Fault Tolerant HPC Systems

    SciTech Connect (OSTI)

    Bronevetsky, G; Meneses, E; Kale, L V

    2011-02-25

    The era of petascale computing brought machines with hundreds of thousands of processors. The next generation of exascale supercomputers will make available clusters with millions of processors. In those machines, mean time between failures will range from a few minutes to few tens of minutes, making the crash of a processor the common case, instead of a rarity. Parallel applications running on those large machines will need to simultaneously survive crashes and maintain high productivity. To achieve that, fault tolerance techniques will have to go beyond checkpoint/restart, which requires all processors to roll back in case of a failure. Incorporating some form of message logging will provide a framework where only a subset of processors are rolled back after a crash. In this paper, we discuss why a simple causal message logging protocol seems a promising alternative to provide fault tolerance in large supercomputers. As opposed to pessimistic message logging, it has low latency overhead, especially in collective communication operations. Besides, it saves messages when more than one thread is running per processor. Finally, we demonstrate that a simple causal message logging protocol has a faster recovery and a low performance penalty when compared to checkpoint/restart. Running NAS Parallel Benchmarks (CG, MG and BT) on 1024 processors, simple causal message logging has a latency overhead below 5%.

  3. Combined expert system/neural networks method for process fault diagnosis

    DOE Patents [OSTI]

    Reifman, Jaques; Wei, Thomas Y. C.

    1995-01-01

    A two-level hierarchical approach for process fault diagnosis is an operating system employs a function-oriented approach at a first level and a component characteristic-oriented approach at a second level, where the decision-making procedure is structured in order of decreasing intelligence with increasing precision. At the first level, the diagnostic method is general and has knowledge of the overall process including a wide variety of plant transients and the functional behavior of the process components. An expert system classifies malfunctions by function to narrow the diagnostic focus to a particular set of possible faulty components that could be responsible for the detected functional misbehavior of the operating system. At the second level, the diagnostic method limits its scope to component malfunctions, using more detailed knowledge of component characteristics. Trained artificial neural networks are used to further narrow the diagnosis and to uniquely identify the faulty component by classifying the abnormal condition data as a failure of one of the hypothesized components through component characteristics. Once an anomaly is detected, the hierarchical structure is used to successively narrow the diagnostic focus from a function misbehavior, i.e., a function oriented approach, until the fault can be determined, i.e., a component characteristic-oriented approach.

  4. Electrical and thermal finite element modeling of arc faults in photovoltaic bypass diodes.

    SciTech Connect (OSTI)

    Bower, Ward Isaac; Quintana, Michael A.; Johnson, Jay

    2012-01-01

    Arc faults in photovoltaic (PV) modules have caused multiple rooftop fires. The arc generates a high-temperature plasma that ignites surrounding materials and subsequently spreads the fire to the building structure. While there are many possible locations in PV systems and PV modules where arcs could initiate, bypass diodes have been suspected of triggering arc faults in some modules. In order to understand the electrical and thermal phenomena associated with these events, a finite element model of a busbar and diode was created. Thermoelectrical simulations found Joule and internal diode heating from normal operation would not normally cause bypass diode or solder failures. However, if corrosion increased the contact resistance in the solder connection between the busbar and the diode leads, enough voltage potentially would be established to arc across micron-scale electrode gaps. Lastly, an analytical arc radiation model based on observed data was employed to predicted polymer ignition times. The model predicted polymer materials in the adjacent area of the diode and junction box ignite in less than 0.1 seconds.

  5. Combined expert system/neural networks method for process fault diagnosis

    DOE Patents [OSTI]

    Reifman, J.; Wei, T.Y.C.

    1995-08-15

    A two-level hierarchical approach for process fault diagnosis of an operating system employs a function-oriented approach at a first level and a component characteristic-oriented approach at a second level, where the decision-making procedure is structured in order of decreasing intelligence with increasing precision. At the first level, the diagnostic method is general and has knowledge of the overall process including a wide variety of plant transients and the functional behavior of the process components. An expert system classifies malfunctions by function to narrow the diagnostic focus to a particular set of possible faulty components that could be responsible for the detected functional misbehavior of the operating system. At the second level, the diagnostic method limits its scope to component malfunctions, using more detailed knowledge of component characteristics. Trained artificial neural networks are used to further narrow the diagnosis and to uniquely identify the faulty component by classifying the abnormal condition data as a failure of one of the hypothesized components through component characteristics. Once an anomaly is detected, the hierarchical structure is used to successively narrow the diagnostic focus from a function misbehavior, i.e., a function oriented approach, until the fault can be determined, i.e., a component characteristic-oriented approach. 9 figs.

  6. Phenomenology of reverse-shock emission in the optical afterglows of gamma-ray bursts

    SciTech Connect (OSTI)

    Japelj, J.; Kopa?, D.; Gomboc, A. [Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, SI-1000 Ljubljana (Slovenia); Kobayashi, S.; Harrison, R.; Virgili, F. J.; Mundell, C. G. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool, L3 5RF (United Kingdom); Guidorzi, C. [Physics Departments, University of Ferrara, via Saragat 1, I-44122, Ferrara (Italy); Melandri, A., E-mail: jure.japelj@fmf.uni-lj.si, E-mail: andreja.gomboc@fmf.uni-lj.si [INAF Osservatorio Astronomico di Brera, via E. Bianchi 46, I-23807 Merate (Italy)

    2014-04-20

    We use a parent sample of 118 gamma-ray burst (GRB) afterglows, with known redshift and host galaxy extinction, to separate afterglows with and without signatures of dominant reverse-shock (RS) emission and to determine which physical conditions lead to a prominent reverse-shock emission. We identify 10 GRBs with reverse-shock signatures: 990123, 021004, 021211, 060908, 061126, 080319B, 081007, 090102, 090424, and 130427A. By modeling their optical afterglows with reverse- and forward-shock analytic light curves and using Monte Carlo simulations, we estimate the parameter space of the physical quantities describing the ejecta and circumburst medium. We find that physical properties cover a wide parameter space and do not seem to cluster around any preferential values. Comparing the rest-frame optical, X-ray, and high-energy properties of the larger sample of non-RS-dominated GRBs, we show that the early-time (<1 ks) optical spectral luminosity, X-ray afterglow luminosity, and ?-ray energy output of our reverse-shock dominated sample do not differ significantly from the general population at early times. However, the GRBs with dominant reverse-shock emission have fainter than average optical forward-shock emission at late times (>10 ks). We find that GRBs with an identifiable reverse-shock component show a high magnetization parameter R {sub B} = ?{sub B,r}/?{sub B,f} ? 2-10{sup 4}. Our results are in agreement with the mildly magnetized baryonic jet model of GRBs.

  7. Area balance and strain in an extensional fault system: Strategies for improved oil recovery in fractured chalk, Gilbertown Field, southwestern Alabama. Annual report, March 1996--March 1997

    SciTech Connect (OSTI)

    Pashin, J.C.; Raymond, D.E.; Rindsberg, A.K.; Alabi, G.G.; Groshong, R.H.

    1997-08-01

    Gilbertown Field is the oldest oil field in Alabama and produces oil from chalk of the Upper Cretaceous Selma Group and from sandstone of the Eutaw Formation along the southern margin of the Gilbertown fault system. Most of the field has been in primary recovery since establishment, but production has declined to marginally economic levels. This investigation applies advanced geologic concepts designed to aid implementation of improved recovery programs. The Gilbertown fault system is detached at the base of Jurassic salt. The fault system began forming as a half graben and evolved in to a full graben by the Late Cretaceous. Conventional trapping mechanisms are effective in Eutaw sandstone, whereas oil in Selma chalk is trapped in faults and fault-related fractures. Burial modeling establishes that the subsidence history of the Gilbertown area is typical of extensional basins and includes a major component of sediment loading and compaction. Surface mapping and fracture analysis indicate that faults offset strata as young as Miocene and that joints may be related to regional uplift postdating fault movement. Preliminary balanced structural models of the Gilbertown fault system indicate that synsedimentary growth factors need to be incorporated into the basic equations of area balance to model strain and predict fractures in Selma and Eutaw reservoirs.

  8. Dynamic modeling of injection-induced fault reactivation and ground motion and impact on surface structures and human perception

    SciTech Connect (OSTI)

    Rutqvist, Jonny; Cappa, Frederic; Rinaldi, Antonio P.; Godano, Maxime

    2014-12-31

    We summarize recent modeling studies of injection-induced fault reactivation, seismicity, and its potential impact on surface structures and nuisance to the local human population. We used coupled multiphase fluid flow and geomechanical numerical modeling, dynamic wave propagation modeling, seismology theories, and empirical vibration criteria from mining and construction industries. We first simulated injection-induced fault reactivation, including dynamic fault slip, seismic source, wave propagation, and ground vibrations. From co-seismic average shear displacement and rupture area, we determined the moment magnitude to about Mw = 3 for an injection-induced fault reactivation at a depth of about 1000 m. We then analyzed the ground vibration results in terms of peak ground acceleration (PGA), peak ground velocity (PGV), and frequency content, with comparison to the U.S. Bureau of Mines vibration criteria for cosmetic damage to buildings, as well as human-perception vibration limits. For the considered synthetic Mw = 3 event, our analysis showed that the short duration, high frequency ground motion may not cause any significant damage to surface structures, and would not cause, in this particular case, upward CO2 leakage, but would certainly be felt by the local population.

  9. Domain wall pinning on strain relaxation defects (stacking faults) in nanoscale FePd (001)/MgO thin films

    SciTech Connect (OSTI)

    Hsiao, C. H.; Ouyang, Chuenhou E-mail: houyang@mx.nthu.edu.tw; Yao, Y. D.; Lo, S. C.; Chang, H. W. E-mail: houyang@mx.nthu.edu.tw

    2015-10-05

    FePd (001) films, prepared by an electron beam deposition system on MgO(100), exhibit a perpendicular magnetic anisotropy (1.7 × 10{sup 7 }erg/cc) with a high order parameter (0.92). The relation between stacking faults induced by the strain relaxation, which act as strong domain wall pinning sites, and the perpendicular coercivity of (001) oriented L1{sub 0} FePd films prepared at different temperatures have been investigated. Perpendicular coercivity can be apparently enhanced by raising the stacking fault densities, which can be elevated by climbing dissociation of total dislocation. The increased stacking fault densities (1.22 nm{sup −2}) with large perpendicular coercivity (6000 Oe) are obtained for samples prepared at 650 °C. This present work shows through controlling stacking fault density in FePd film, the coercivity can be manipulated, which can be applied in future magnetic devices.

  10. Power line fault current coupling to nearby natural gas pipelines: Volume 3, Analysis of pipeline coating impedance: Final report

    SciTech Connect (OSTI)

    Dabkowski, J.; Frazier, M. J.

    1988-08-01

    This report is a compilation of results obtained from two research programs. The response of a pipeline and coating at the higher voltage excitation levels encountered under power line fault conditions appears to be dominated by conduction at holiday sites in the coating. A simple analytical model was developed for predicting the resistance of a pipeline coating holiday as a function of the voltage produced across the pipeline coating by a nearby faulted power transmission line. The model was initially validated using coated pipeline samples stressed by a capacitive discharge voltage. Additional validation tests were then performed at the Pacific Gas and Electric Company's High Voltage Engineering Research Facility using high voltage ac waveforms for fault simulation. The principle program objective was to develop, both by laboratory and controlled field testing, an electrical resistance characterization for the pipeline coating as a function of the applied voltage level. The development of this model will allow a more accurate prediction of coupled voltage levels to a pipeline during fault current conditions. 54 figs, 3 tabs.

  11. Dynamic modeling of injection-induced fault reactivation and ground motion and impact on surface structures and human perception

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

    Rutqvist, Jonny; Cappa, Frederic; Rinaldi, Antonio P.; Godano, Maxime

    2014-12-31

    We summarize recent modeling studies of injection-induced fault reactivation, seismicity, and its potential impact on surface structures and nuisance to the local human population. We used coupled multiphase fluid flow and geomechanical numerical modeling, dynamic wave propagation modeling, seismology theories, and empirical vibration criteria from mining and construction industries. We first simulated injection-induced fault reactivation, including dynamic fault slip, seismic source, wave propagation, and ground vibrations. From co-seismic average shear displacement and rupture area, we determined the moment magnitude to about Mw = 3 for an injection-induced fault reactivation at a depth of about 1000 m. We then analyzed themore » ground vibration results in terms of peak ground acceleration (PGA), peak ground velocity (PGV), and frequency content, with comparison to the U.S. Bureau of Mines’ vibration criteria for cosmetic damage to buildings, as well as human-perception vibration limits. For the considered synthetic Mw = 3 event, our analysis showed that the short duration, high frequency ground motion may not cause any significant damage to surface structures, and would not cause, in this particular case, upward CO2 leakage, but would certainly be felt by the local population.« less

  12. Fault tolerance in an inner-outer solver: A GVR-enabled case study

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

    Zhang, Ziming; Chien, Andrew A.; Teranishi, Keita

    2015-04-18

    Resilience is a major challenge for large-scale systems. It is particularly important for iterative linear solvers, since they take much of the time of many scientific applications. We show that single bit flip errors in the Flexible GMRES iterative linear solver can lead to high computational overhead or even failure to converge to the right answer. Informed by these results, we design and evaluate several strategies for fault tolerance in both inner and outer solvers appropriate across a range of error rates. We implement them, extending Trilinos’ solver library with the Global View Resilience (GVR) programming model, which provides multi-streammore » snapshots, multi-version data structures with portable and rich error checking/recovery. Lastly, experimental results validate correct execution with low performance overhead under varied error conditions.« less

  13. Methods and apparatuses for self-generating fault-tolerant keys in spread-spectrum systems

    DOE Patents [OSTI]

    Moradi, Hussein; Farhang, Behrouz; Subramanian, Vijayarangam

    2015-12-15

    Self-generating fault-tolerant keys for use in spread-spectrum systems are disclosed. At a communication device, beacon signals are received from another communication device and impulse responses are determined from the beacon signals. The impulse responses are circularly shifted to place a largest sample at a predefined position. The impulse responses are converted to a set of frequency responses in a frequency domain. The frequency responses are shuffled with a predetermined shuffle scheme to develop a set of shuffled frequency responses. A set of phase differences is determined as a difference between an angle of the frequency response and an angle of the shuffled frequency response at each element of the corresponding sets. Each phase difference is quantized to develop a set of secret-key quantized phases and a set of spreading codes is developed wherein each spreading code includes a corresponding phase of the set of secret-key quantized phases.

  14. Wrench fault tectonics in northern New Guinea basin, Papua New Guinea

    SciTech Connect (OSTI)

    Trumbly, N.I.; Pigott, J.D.

    1984-04-01

    New Guinea lies on the northern Australian plate boundary and has been a sensitive tectonic recorder of Cenozoic plate interactions between the Australian and Pacific plates. The specific plate interactions are documented by the evolution of the Northern New Guinea fault system and the basin it overprints, the Northern New Guinea basin. Consideration of plate kinematics suggests convergence became increasingly oblique during the Cenozoic. Hydrocarbon exploration strategies within the Northern New Guinea basin must address not only sedimentation, but also must deal with the basin's complex structural and tectonic evolution. A static tectonic classification will not adequately define the Northern New Guinea basin. It is better described as an evolving basin being overprinted by wrenching.

  15. Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters

    SciTech Connect (OSTI)

    Frank Darmann; Robert Lombaerde; Franco Moriconi; Albert Nelson

    2011-10-31

    Zenergy Power has successfully designed, built, tested, and installed in the US electrical grid a saturable reactor Fault Current Limiter. Beginning in 2007, first as SC Power Systems and from 2008 as Zenergy Power, Inc., ZP used DOE matching grant and ARRA funds to help refine the design of the saturated reactor fault current limiter. ZP ultimately perfected the design of the saturated reactor FCL to the point that ZP could reliably design a suitable FCL for most utility applications. Beginning with a very basic FCL design using 1G HTS for a coil housed in a LN2 cryostat for the DC bias magnet, the technology progressed to a commercial system that was offered for sale internationally. Substantial progress was made in two areas. First, the cryogenics cooling system progressed from a sub-cooled liquid nitrogen container housing the HTS coils to cryostats utilizing dry conduction cooling and reaching temperatures down to less than 20 degrees K. Large, round cryostats with “warm bore” diameters of 1.7 meters enabled the design of large tanks to hold the AC components. Second, the design of the AC part of the FCL was refined from a six legged “spider” design to a more compact and lighter design with better fault current limiting capability. Further refinement of the flux path and core shape led to an efficient saturated reactor design requiring less Ampere-turns to saturate the core. In conclusion, the development of the saturable reactor FCL led to a more efficient design not requiring HTS magnets and their associated peripheral equipment, which yielded a more economical product in line with the electric utility industry expectations. The original goal for the DOE funding of the ZP project “Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters” was to stimulate the HTS wire industry with, first 1G, then 2G, HTS wire applications. Over the approximately 5 years of ZP’s product

  16. Fault tolerance in an inner-outer solver: A GVR-enabled case study

    SciTech Connect (OSTI)

    Zhang, Ziming; Chien, Andrew A.; Teranishi, Keita

    2015-04-18

    Resilience is a major challenge for large-scale systems. It is particularly important for iterative linear solvers, since they take much of the time of many scientific applications. We show that single bit flip errors in the Flexible GMRES iterative linear solver can lead to high computational overhead or even failure to converge to the right answer. Informed by these results, we design and evaluate several strategies for fault tolerance in both inner and outer solvers appropriate across a range of error rates. We implement them, extending Trilinos’ solver library with the Global View Resilience (GVR) programming model, which provides multi-stream snapshots, multi-version data structures with portable and rich error checking/recovery. Lastly, experimental results validate correct execution with low performance overhead under varied error conditions.

  17. Basic criteria for formation of growth twins in high stacking fault energy metals

    SciTech Connect (OSTI)

    Yu, K. Y.; Zhang, X.; Bufford, D.; Chen, Y.; Liu, Y.; Wang, H.

    2013-10-28

    Nanotwinned metals received significant interest lately as twin boundaries may enable simultaneous enhancement of strength, ductility, thermal stability, and radiation tolerance. However, nanotwins have been the privilege of metals with low-to-intermediate stacking fault energy (SFE). Recent scattered studies show that nanotwins could be introduced into high SFE metals, such as Al. In this paper, we examine several sputter-deposited, (111) textured Ag/Al, Cu/Ni, and Cu/Fe multilayers, wherein growth twins were observed in Al, Ni, and face-centered cubic (fcc) Fe. The comparisons lead to two important design criteria that dictate the introduction of growth twins in high SFE metals. The validity of these criteria was then examined in Ag/Ni multilayers. Furthermore, another twin formation mechanism in high SFE metals was discovered in Ag/Ni system.

  18. A complex systems analysis of stick-slip dynamics of a laboratory fault

    SciTech Connect (OSTI)

    Walker, David M.; Tordesillas, Antoinette; Small, Michael; Behringer, Robert P.; Tse, Chi K.

    2014-03-15

    We study the stick-slip behavior of a granular bed of photoelastic disks sheared by a rough slider pulled along the surface. Time series of a proxy for granular friction are examined using complex systems methods to characterize the observed stick-slip dynamics of this laboratory fault. Nonlinear surrogate time series methods show that the stick-slip behavior appears more complex than a periodic dynamics description. Phase space embedding methods show that the dynamics can be locally captured within a four to six dimensional subspace. These slider time series also provide an experimental test for recent complex network methods. Phase space networks, constructed by connecting nearby phase space points, proved useful in capturing the key features of the dynamics. In particular, network communities could be associated to slip events and the ranking of small network subgraphs exhibited a heretofore unreported ordering.

  19. Assessment study of superconducting fault-current limiters operating at 77K

    SciTech Connect (OSTI)

    Giese, R.F. ); Runde, M. )

    1992-01-01

    The possible impact of nitrogen-cooled superconductors on the design and cost of superconducting fault-current limiters is assessed by considering the technical specifications such devices must meet and by comparing material properties of 77-K and 4-K superconductors. The main advantage of operating superconductors at 77 K is that the refrigeration operating cost is reduced by a factor of up to 25, and the refrigeration capital cost is reduced by a factor of up to 10. The heat capacity of 77 K is several orders of magnitude larger than at 4 K. This phenomenon increases conductor stability against flux jumps but makes switching from the superconducting to normal state slow and difficult. Consequently, a high critical current density, probably at least 10{sup 5} A/cm{sup 2}, is required.

  20. Assessment study of superconducting fault-current limiters operating at 77K

    SciTech Connect (OSTI)

    Giese, R.F.; Runde, M.

    1992-07-01

    The possible impact of nitrogen-cooled superconductors on the design and cost of superconducting fault-current limiters is assessed by considering the technical specifications such devices must meet and by comparing material properties of 77-K and 4-K superconductors. The main advantage of operating superconductors at 77 K is that the refrigeration operating cost is reduced by a factor of up to 25, and the refrigeration capital cost is reduced by a factor of up to 10. The heat capacity of 77 K is several orders of magnitude larger than at 4 K. This phenomenon increases conductor stability against flux jumps but makes switching from the superconducting to normal state slow and difficult. Consequently, a high critical current density, probably at least 10{sup 5} A/cm{sup 2}, is required.

  1. Methods and apparatuses for self-generating fault-tolerant keys in spread-spectrum systems

    DOE Patents [OSTI]

    Moradi, Hussein; Farhang, Behrouz; Subramanian, Vijayarangam

    2015-12-22

    Self-generating fault-tolerant keys for use in spread-spectrum systems are disclosed. At a communication device, beacon signals are received from another communication device and impulse responses are determined from the beacon signals. The impulse responses are circularly shifted to place a largest sample at a predefined position. The impulse responses are converted to a set of frequency responses in a frequency domain. The frequency responses are shuffled with a predetermined shuffle scheme to develop a set of shuffled frequency responses. A set of phase differences is determined as a difference between an angle of the frequency response and an angle of the shuffled frequency response at each element of the corresponding sets. Each phase difference is quantized to develop a set of secret-key quantized phases and a set of spreading codes is developed wherein each spreading code includes a corresponding phase of the set of secret-key quantized phases.

  2. Reversal of the Upper Critical Field Anisotropy and Spin-Locked...

    Office of Scientific and Technical Information (OSTI)

    Spin-Locked Superconductivity in K2Cr3As3 Citation Details In-Document Search Title: Reversal of the Upper Critical Field Anisotropy and Spin-Locked Superconductivity in K2Cr3As3 ...

  3. Real space mapping of oxygen vacancy diffusion and electrochemical transformations by hysteretic current reversal curve measurements

    DOE Patents [OSTI]

    Kalinin, Sergei V.; Balke, Nina; Borisevich, Albina Y.; Jesse, Stephen; Maksymovych, Petro; Kim, Yunseok; Strelcov, Evgheni

    2014-06-10

    An excitation voltage biases an ionic conducting material sample over a nanoscale grid. The bias sweeps a modulated voltage with increasing maximal amplitudes. A current response is measured at grid locations. Current response reversal curves are mapped over maximal amplitudes of the bias cycles. Reversal curves are averaged over the grid for each bias cycle and mapped over maximal bias amplitudes for each bias cycle. Average reversal curve areas are mapped over maximal amplitudes of the bias cycles. Thresholds are determined for onset and ending of electrochemical activity. A predetermined number of bias sweeps may vary in frequency where each sweep has a constant number of cycles and reversal response curves may indicate ionic diffusion kinetics.

  4. A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic disks: distorted viscous vortex

    SciTech Connect (OSTI)

    Gilbert, Dustin A.; Ye, Li; Varea, Aïda; Agramunt-Puig, Sebastià; del Valle, Nuria; Navau, Carles; López-Barbera, José Francisco; Buchanan, Kristen S.; Hoffmann, Axel; Sánchez, Alvar; Sort, Jordi; Liu, Kai; Nogués, Josep

    2015-04-28

    Magnetic vortices have generated intense interest in recent years due to their unique reversal mechanisms, fascinating topological properties, and exciting potential applications. In addition, the exchange coupling of magnetic vortices to antiferromagnets has also been shown to lead to a range of novel phenomena and functionalities. Here we report a new magnetization reversal mode of magnetic vortices in exchange coupled Ir20Mn80/Fe20Ni80 microdots: distorted viscous vortex reversal. In contrast to the previously known or proposed reversal modes, the vortex is distorted close to the interface and viscously dragged due to the uncompensated spins of a thin antiferromagnet, which leads to unexpected asymmetries in the annihilation and nucleation fields. These results provide a deeper understanding of the physics of exchange coupled vortices and may also have important implications for applications involving exchange coupled nanostructures.

  5. Nano-scale Composite Hetero-structures: Novel High Capacity Reversible...

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

    0kumta.pdf (1.9 MB) More Documents & Publications Nano-scale Composite Hetero-structures: Novel High Capacity Reversible Anodes for Lithium-ion Batteries Nanoscale ...

  6. Magnetization reversal in CoPt(111) hard/soft bilayers

    SciTech Connect (OSTI)

    Alexandrakis, V.; Niarchos, D.; Wolff, M.

    2009-03-15

    The magnetization reversal in magnetron sputtered CoPt(111) hard/soft bilayers has been studied by polarized neutron reflectometry and magnetization measurements. The stability of the hard layer is tuned by the heat-treatment conditions which are used to crystallize the chemically ordered, high anisotropy, L{sub 1}0 phase. All the samples show the same features in their first order reversal curves but the lateral domain size during the magnetization reversal of the soft layer differs. In samples with strong intergrain coupling it exceeds the coherence length of the neutron beam, resulting in spin-flip scattering. In contrast, the hard layer reversal occurs through the reorientation in small domains.

  7. Colorado - C.R.S. 36-1-136 - Rights of Way Granted - Reversion...

    Open Energy Info (EERE)

    search OpenEI Reference LibraryAdd to library Legal Document- StatuteStatute: Colorado - C.R.S. 36-1-136 - Rights of Way Granted - ReversionLegal Abstract This section covers the...

  8. A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic disks: distorted viscous vortex

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

    Gilbert, Dustin A.; Ye, Li; Varea, Aïda; Agramunt-Puig, Sebastià; del Valle, Nuria; Navau, Carles; López-Barbera, José Francisco; Buchanan, Kristen S.; Hoffmann, Axel; Sánchez, Alvar; et al

    2015-04-28

    Magnetic vortices have generated intense interest in recent years due to their unique reversal mechanisms, fascinating topological properties, and exciting potential applications. In addition, the exchange coupling of magnetic vortices to antiferromagnets has also been shown to lead to a range of novel phenomena and functionalities. Here we report a new magnetization reversal mode of magnetic vortices in exchange coupled Ir20Mn80/Fe20Ni80 microdots: distorted viscous vortex reversal. In contrast to the previously known or proposed reversal modes, the vortex is distorted close to the interface and viscously dragged due to the uncompensated spins of a thin antiferromagnet, which leads to unexpectedmore » asymmetries in the annihilation and nucleation fields. These results provide a deeper understanding of the physics of exchange coupled vortices and may also have important implications for applications involving exchange coupled nanostructures.« less

  9. Final Technical Report Recovery Act: Online Nonintrusive Condition Monitoring and Fault Detection for Wind Turbines

    SciTech Connect (OSTI)

    Wei Qiao

    2012-05-29

    The penetration of wind power has increased greatly over the last decade in the United States and across the world. The U.S. wind power industry installed 1,118 MW of new capacity in the first quarter of 2011 alone and entered the second quarter with another 5,600 MW under construction. By 2030, wind energy is expected to provide 20% of the U.S. electricity needs. As the number of wind turbines continues to grow, the need for effective condition monitoring and fault detection (CMFD) systems becomes increasingly important [3]. Online CMFD is an effective means of not only improving the reliability, capacity factor, and lifetime, but it also reduces the downtime, energy loss, and operation and maintenance (O&M) of wind turbines. The goal of this project is to develop novel online nonintrusive CMFD technologies for wind turbines. The proposed technologies use only the current measurements that have been used by the control and protection system of a wind turbine generator (WTG); no additional sensors or data acquisition devices are needed. Current signals are reliable and easily accessible from the ground without intruding on the wind turbine generators (WTGs) that are situated on high towers and installed in remote areas. Therefore, current-based CMFD techniques have great economic benefits and the potential to be adopted by the wind energy industry. Specifically, the following objectives and results have been achieved in this project: (1) Analyzed the effects of faults in a WTG on the generator currents of the WTG operating at variable rotating speed conditions from the perspective of amplitude and frequency modulations of the current measurements; (2) Developed effective amplitude and frequency demodulation methods for appropriate signal conditioning of the current measurements to improve the accuracy and reliability of wind turbine CMFD; (3) Developed a 1P-invariant power spectrum density (PSD) method for effective signature extraction of wind turbine faults with

  10. FLUX ENHANCEMENT IN CROSSFLOW MEMBRANE FILTRATION: FOULING AND IT'S MINIMIZATION BY FLOW REVERSAL

    SciTech Connect (OSTI)

    Shamsuddin Ilias

    2005-01-25

    Fouling problems are perhaps the single most important reason for relatively slow acceptance of ultrafiltration in many areas of chemical and biological processing. To overcome the losses in permeate flux associated with concentration polarization and fouling in cross flow membrane filtration, we investigated the concept of flow reversal as a method to enhance membrane flux in ultrafiltration. Conceptually, flow reversal prevents the formation of stable hydrodynamic and concentration boundary layers at or near the membrane surface. Further more, periodic reversal of the flow direction of the feed stream at the membrane surface results in prevention and mitigation of membrane fouling. Consequently, these advantages are expected to enhance membrane flux significantly. A crossflow membrane filtration unit was designed and built to test the concept of periodic flow reversal for flux enhancement. The essential elements of the system include a crossflow hollow fiber membrane module integrated with a two-way valve to direct the feed flow directions. The two-way valve is controlled by a controller-timer for periodic reversal of flow of feed stream. Another important feature of the system is that with changing feed flow direction, the permeate flow direction is also changed to maintain countercurrent feed and permeate flows for enhanced mass transfer driving force (concentration difference). In this report, we report our application of Flow Reversal technique in clarification of apple juice containing pectin. The presence of pectin in apple juice makes the clarification process difficult and is believed to cause membrane fouling. Of all compounds found in apple juice, pectin is most often identified as the major hindrance to filtration performance. Based on our ultrafiltration experiments with apple juice, we conclude that under flow reversal conditions, the permeate flux is significantly enhanced when compared with the conventional unidirectional flow. Thus, flow reversal

  11. Fullrmc, A Rigid Body Reverse Monte Carlo Modeling Package Enabled With

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

    Machine Learning And Artificial Intelligence - Joint Center for Energy Storage Research January 22, 2016, Research Highlights Fullrmc, A Rigid Body Reverse Monte Carlo Modeling Package Enabled With Machine Learning And Artificial Intelligence Liquid Sulfur. Sx≤8 molecules recognized and built upon modelling Scientific Achievement Novel approach to reverse modelling atomic and molecular systems from a set of experimental data and constraints. New fitting concepts such as 'Group',

  12. High Temperature Reverse By-Pass Diodes Bias and Failures | Department of

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

    Energy Reverse By-Pass Diodes Bias and Failures High Temperature Reverse By-Pass Diodes Bias and Failures Presented at the PV Module Reliability Workshop, February 26 - 27 2013, Golden, Colorado pvmrw13_ps3_memc_posbic.pdf (498.72 KB) More Documents & Publications US & Japan TG 4 Activities of QA Forum Thermal Reliability Study of Bypass Diodes in Photovoltaic Modules US TG 4 Activities of QA Forum

  13. Reverse logistics system and recycling potential at a landfill: A case study from Kampala City

    SciTech Connect (OSTI)

    Kinobe, J.R.; Gebresenbet, G.; Niwagaba, C.B.; Vinnerås, B.

    2015-08-15

    Highlights: • Quantifies the different waste streams delivered at the landfill. • Evaluates the amount of potential waste products that enters into the reverse cycle. • Drawing out the reverse logistics activities from Kampala City to Kiteezi landfill. • Identify the storage, collection and transportation mechanisms of products to the various destinations; and finally. • The study suggests efficient measures to improve reverse logistics system. - Abstract: The rapid growing population and high urbanisation rates in Sub-Saharan Africa has caused enormous pressure on collection services of the generated waste in the urban areas. This has put a burden on landfilling, which is the major waste disposal method. Waste reduction, re-use and recycling opportunities exist but are not fully utilized. The common items that are re-used and re-cycled are plastics, paper, aluminum, glass, steel, cardboard, and yard waste. This paper develops an overview of reverse logistics at Kiteezi landfill, the only officially recognised waste disposal facility for Kampala City. The paper analyses, in details the collection, re-processing, re-distribution and final markets of these products into a reversed supply chain network. Only 14% of the products at Kiteezi landfill are channeled into the reverse chain while 63% could be included in the distribution chain but are left out and disposed of while the remaining 23% is buried. This is because of the low processing power available, lack of market value, lack of knowledge and limited value addition activities to the products. This paper proposes possible strategies of efficient and effective reverse logistics development, applicable to Kampala City and other similar cities.

  14. Flux Enhancement in Crossflow Membrane Filtration: Fouling and It's Minimization by Flow Reversal

    SciTech Connect (OSTI)

    Shamsuddin Ilias

    2005-08-04

    Fouling problems are perhaps the single most important reason for relatively slow acceptance of ultrafiltration in many areas of chemical and biological processing. To overcome the losses in permeate flux associated with concentration polarization and fouling in cross flow membrane filtration, we investigated the concept of flow reversal as a method to enhance membrane flux in ultrafiltration. Conceptually, flow reversal prevents the formation of stable hydrodynamic and concentration boundary layers at or near the membrane surface. Further more, periodic reversal of the flow direction of the feed stream at the membrane surface results in prevention and mitigation of membrane fouling. Consequently, these advantages are expected to enhance membrane flux significantly. A crossflow membrane filtration unit was designed and built to test the concept of periodic flow reversal for flux enhancement. The essential elements of the system include a crossflow hollow fiber membrane module integrated with a two-way valve to direct the feed flow directions. The two-way valve is controlled by a controller-timer for periodic reversal of flow of feed stream. Another important feature of the system is that with changing feed flow direction, the permeate flow direction is also changed to maintain countercurrent feed and permeate flows for enhanced mass transfer driving force (concentration difference). Three feed solutions (Bovine serum albumin (BSA), apple juice and citrus fruit pectin) were studied in crossflow membrane filtration. These solutes are well-known in membrane filtration for their fouling and concentration polarization potentials. Laboratory-scale tests on a hollow-fiber ultrafiltration membrane module using each of the feed solutes show that under flow reversal conditions, the permeate flux is significantly enhanced when compared with the conventional unidirectional flow. The flux enhancement is dramatic (by an order of magnitude) with increased feed concentration and

  15. FLUX ENHANCEMENT IN CROSSFLOW MEMBRANE FILTRATION: FOULING AND IT'S MINIMIZATION BY FLOW REVERSAL

    SciTech Connect (OSTI)

    Shamsuddin Ilias

    2004-06-14

    Fouling problems are perhaps the single most important reason for relatively slow acceptance of ultrafiltration in many areas of chemical and biological processing. To overcome the losses in permeate flux associated with concentration polarization and fouling in cross flow membrane filtration, we investigated the concept of flow reversal as a method to enhance membrane flux in ultrafiltration. Conceptually, flow reversal prevents the formation of stable hydrodynamic and concentration boundary layers at or near the membrane surface. Further more, periodic reversal of the flow direction of the feed stream at the membrane surface results in prevention and mitigation of membrane fouling. Consequently, these advantages are expected to enhance membrane flux significantly. A crossflow membrane filtration unit was designed and built to test the concept of periodic flow reversal for flux enhancement. The essential elements of the system include a crossflow hollow fiber membrane module integrated with a two-way valve to direct the feed flow directions. The two-way valve is controlled by a controller-timer for periodic reversal of flow of feed stream. Another important feature of the system is that with changing feed flow direction, the permeate flow direction is also changed to maintain countercurrent feed and permeate flows for enhanced mass transfer driving force (concentration difference). In our previous report, we reported our work on UF of BSA. In this report, we report our continuing application of Flow Reversal technique in clarification of apple juice containing pectin. The presence of pectin in apple juice makes the clarification process difficult and is believed to cause membrane fouling. Of all compounds found in apple juice, pectin is most often identified as the major hindrance to filtration performance. Laboratory-scale tests on a hollow-fiber ultrafiltration membrane module using pectin in apple juice as feed show that under flow reversal conditions, the

  16. Design, Fabrication and Testing of a Superconducting Fault Current Limiter (SFCL)

    SciTech Connect (OSTI)

    Gouge, M..; Schwenterly, S.W.; Hazelton, D.

    2011-06-15

    The purpose of this project was to conduct R&D on specified components and provide technical design support to a SuperPower team developing a high temperature superconducting Fault Current Limiter (SFCL). ORNL teamed with SuperPower, Inc. on a Superconductivity Partnerships with Industry (SPI) proposal for the SFCL that was submitted to DOE and approved in FY 2003. A contract between DOE and SuperPower, Inc. was signed on July 14, 2003 to design, fabricate and test the SFCL. This device employs high temperature superconducting (HTS) elements and SuperPower's proprietary technology. The program goal was to demonstrate a device that will address a broad range of the utility applications and meet utility industry requirements. This DOE-sponsored Superconductivity Partnership with Industry project would positively impact electric power transmission reliability and security by introducing a new element in the grid that can significantly mitigate fault currents and provide lower cost solutions for grid protection. The project will conduct R&D on specified components and provide technical design support to a SuperPower-led team developing a SFCL as detailed in tasks 1-5 below. Note the SuperPower scope over the broad SPI project is much larger than that shown below which indicates only the SuperPower tasks that are complementary to the ORNL tasks. SuperPower is the Project Manager for the SFCL program, and is responsible for completion of the project on schedule and budget. The scope of work for ORNL is to provide R&D support for the SFCL in the following four broad areas: (1) Assist with high voltage subsystem R&D, design, fabrication and testing including characterization of the general dielectric performance of LN2 and component materials; (2) Consult on cryogenic subsystem R&D, design, fabrication and testing; (3) Participate in project conceptual and detailed design reviews; and (4) Guide commercialization by participation on the Technical Advisory Board (TAB). Super

  17. Theoretical, numerical and experimental investigation of centrifugal pumps in reverse operation

    SciTech Connect (OSTI)

    Derakhshan, Shahram; Nourbakhsh, Ahmad

    2008-09-15

    When a pump works as a turbine, its hydraulic behavior will be changed. Several methods have been developed to predict the best efficiency of pumps running as turbines but their results are not in good coincidence with experimental data for all pumps. Therefore, study and investigation of hydraulic behavior of pumps in reverse operation can be useful. In this study, the best efficiency point of an industrial centrifugal pump running as turbine was achieved using a theoretical analysis. This method tries to estimate hydraulic components of reverse (turbine) mode using direct (pump) mode. In the next step, the pump was simulated in direct and reverse modes by computational fluid dynamics. 3D full Navier-Stokes equations were solved using FineTurbo V.7 flow solver. Using numerical results, complete characteristic curves of the pump in direct and reverse modes were obtained. For experimental verification of theoretical and numerical results, the pump was tested as a turbine in a test rig. All required parameters were measured to achieve complete characteristic curves of the reverse pump. The theoretical and numerical results were compared with experimental data and some other methods. (author)

  18. Intrinsic torque reversals induced by magnetic shear effects on the turbulence spectrum in tokamak plasmas

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

    Lu, Z. X.; Wang, W. X.; Diamond, P. H.; Tynan, G.; Ethier, S.; Gao, C.; Rice, J.

    2015-05-04

    We report that intrinsic torque, which can be generated by turbulent stresses, can induce toroidal rotation in a tokamak plasma at rest without direct momentum injection. Reversals in intrinsic torque have been inferred from the observation of toroidal velocity changes in recent lower hybrid current drive (LHCD) experiments. Here we focus on understanding the cause of LHCD-induced intrinsic torque reversal using gyrokinetic simulations and theoretical analyses. A new mechanism for the intrinsic torque reversal linked to magnetic shear (sˆ) effects on the turbulence spectrum is identified. This reversal is a consequence of the ballooning structure at weak sˆ . Basedmore » on realistic profiles from the Alcator C-Mod LHCD experiments, simulations demonstrate that the intrinsic torque reverses for weak sˆ discharges and that the value of sˆ crit is consistent with the experimental results sˆ expcrit [Rice et al., Phys. Rev. Lett. 111, 125003 (2013)]. In conclusion, the consideration of this intrinsic torque feature in our work is important for the understanding of rotation profile generation at weak and its consequent impact on macro-instability stabilization and micro-turbulence reduction, which is crucial for ITER. It is also relevant to internal transport barrier formation at negative or weakly positive sˆ .« less

  19. Superelasticity by reversible variant reorientation in a Ni-Mn-Ga microwire with bamboo grains

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

    Wang, Z. L.; Zheng, P.; Nie, Z. H.; Ren, Y.; Wang, Y. D.; Mullner, P.; Dunand, D. C.

    2015-08-26

    The link between microstructure and mechanical properties is investigated for a superelastic Ni–Mn–Ga microwire with 226 μm diameter, created by solidification via the Taylor method. The wire, which consists of bamboo grains with tetragonal martensite matrix and coarse γ precipitates, exhibits fully reversible superelastic behavior up to 4% tensile strain. Upon multiple tensile load–unload cycles, reproducible stress fluctuations of ~3 MPa are measured on the loading superelastic stress plateau of ~50 MPa. During cycles at various temperatures spanning -70 to 55 °C, the plateau stress decreases from 58 to 48 MPa near linearly with increasing temperature. Based on in situmore » synchrotron X-ray diffraction measurements, we conclude that this superelastic behavior is due to reversible martensite variants reorientation (i.e., reversible twinning) with lattice rotation of ~13°. The reproducible stress plateau fluctuations are assigned to reversible twinning at well-defined locations along the wire. The strain recovery during unloading is attributed to reverse twinning, driven by the internal stress generated on loading between the elastic γ precipitates and the twinning martensite matrix. Lastly, the temperature dependence of the twining stress on loading is related to the change in tetragonality of the martensite, as measured by X-ray diffraction.« less

  20. Superelasticity by reversible variant reorientation in a Ni-Mn-Ga microwire with bamboo grains

    SciTech Connect (OSTI)

    Wang, Z. L.; Zheng, P.; Nie, Z. H.; Ren, Y.; Wang, Y. D.; Mullner, P.; Dunand, D. C.

    2015-08-26

    The link between microstructure and mechanical properties is investigated for a superelastic Ni–Mn–Ga microwire with 226 μm diameter, created by solidification via the Taylor method. The wire, which consists of bamboo grains with tetragonal martensite matrix and coarse γ precipitates, exhibits fully reversible superelastic behavior up to 4% tensile strain. Upon multiple tensile load–unload cycles, reproducible stress fluctuations of ~3 MPa are measured on the loading superelastic stress plateau of ~50 MPa. During cycles at various temperatures spanning -70 to 55 °C, the plateau stress decreases from 58 to 48 MPa near linearly with increasing temperature. Based on in situ synchrotron X-ray diffraction measurements, we conclude that this superelastic behavior is due to reversible martensite variants reorientation (i.e., reversible twinning) with lattice rotation of ~13°. The reproducible stress plateau fluctuations are assigned to reversible twinning at well-defined locations along the wire. The strain recovery during unloading is attributed to reverse twinning, driven by the internal stress generated on loading between the elastic γ precipitates and the twinning martensite matrix. Lastly, the temperature dependence of the twining stress on loading is related to the change in tetragonality of the martensite, as measured by X-ray diffraction.

  1. High field strength following the Kauai R-N geomagnetic reversal

    SciTech Connect (OSTI)

    Paul, H.A. . Dept. of Geology)

    1993-04-01

    The paleomagnetism of superposed lava flows on Kauai, Hawaii shows that the ancient geomagnetic field was unusually strong following a reverse-to-normal polarity transition that occurred about 4 million years ago. Paleointensities were determined by a standard experimental procedure (Thelliers' method) that recreates the process of remanence acquisition in volcanic rocks. This experiment makes it possible to infer the strength of the geomagnetic field present with each lava flow formed, thus producing an accurate picture of the ancient field's behavior after the reversal. Samples from 10 volcanic units yielded virtual dipole moments (VDMs) ranging from 7.4 [times] 10[sup 22] Am[sup 2] to 14.5 [times] 10[sup 22] Am[sup 2] with an average of 11.1[times]10[sup 22] Am[sup 2]. This value is high in comparisons to the average VDM for the past 5 m.y., approximately 8.7[times]10[sup 22] Am[sup 2]. In contrast to the highly variable dipole moment observed following a 15 m.y. old reversal at Steen s Mountain, Oregon, the field following the Kauai transition was relatively steady. Surprisingly, the maximum dipole moments following the two reversals were nearly equal. This similarity hints that high field strength may be a systematic feature of the geodynamo immediately following a polarity reversal.

  2. Some fundamental aspects of fault-tree and digraph-matrix relationships for a systems-interaction evaluation procedure

    SciTech Connect (OSTI)

    Alesso, H.P.

    1982-02-28

    Recent events, such as Three Mile Island-2, Brown's Ferry-3, and Crystal River-3, have demonstrated that complex accidents can occur as a result of dependent (common-cause/mode) failures. These events are now being called Systems Interactions. A procedure for the identification and evaluation of Systems Interactions is being developed by the NRC. Several national laboratories and utilities have contributed preliminary procedures. As a result, there are several important views of the Systems Interaction problem. This report reviews some fundamental mathematical background of both fault-oriented and success-oriented risk analyses in order to bring out the advantages and disadvantages of each. In addition, it outlines several fault-oriented/dependency analysis approaches and several success-oriented/digraph-matrix approaches. The objective is to obtain a broad perspective of present options for solving the Systems Interaction problem.

  3. Effects of Volcanism, Crustal Thickness, and Large Scale Faulting on the Development and Evolution of Geothermal Systems: Collaborative Project in Chile

    Broader source: Energy.gov [DOE]

    Effects of Volcanism, Crustal Thickness, and Large Scale Faulting on the Development and Evolution of Geothermal Systems: Collaborative Project in Chile presentation at the April 2013 peer review meeting held in Denver, Colorado.

  4. Comparison of chiller models for use in model-based fault detection

    SciTech Connect (OSTI)

    Sreedharan, Priya; Haves, Philip

    2001-06-07

    Selecting the model is an important and essential step in model based fault detection and diagnosis (FDD). Factors that are considered in evaluating a model include accuracy, training data requirements, calibration effort, generality, and computational requirements. The objective of this study was to evaluate different modeling approaches for their applicability to model based FDD of vapor compression chillers. Three different models were studied: the Gordon and Ng Universal Chiller model (2nd generation) and a modified version of the ASHRAE Primary Toolkit model, which are both based on first principles, and the DOE-2 chiller model, as implemented in CoolTools{trademark}, which is empirical. The models were compared in terms of their ability to reproduce the observed performance of an older, centrifugal chiller operating in a commercial office building and a newer centrifugal chiller in a laboratory. All three models displayed similar levels of accuracy. Of the first principles models, the Gordon-Ng model has the advantage of being linear in the parameters, which allows more robust parameter estimation methods to be used and facilitates estimation of the uncertainty in the parameter values. The ASHRAE Toolkit Model may have advantages when refrigerant temperature measurements are also available. The DOE-2 model can be expected to have advantages when very limited data are available to calibrate the model, as long as one of the previously identified models in the CoolTools library matches the performance of the chiller in question.

  5. ROSE::FTTransform - A Source-to-Source Translation Framework for Exascale Fault-Tolerance Research

    SciTech Connect (OSTI)

    Lidman, J; Quinlan, D; Liao, C; McKee, S

    2012-03-26

    Exascale computing systems will require sufficient resilience to tolerate numerous types of hardware faults while still assuring correct program execution. Such extreme-scale machines are expected to be dominated by processors driven at lower voltages (near the minimum 0.5 volts for current transistors). At these voltage levels, the rate of transient errors increases dramatically due to the sensitivity to transient and geographically localized voltage drops on parts of the processor chip. To achieve power efficiency, these processors are likely to be streamlined and minimal, and thus they cannot be expected to handle transient errors entirely in hardware. Here we present an open, compiler-based framework to automate the armoring of High Performance Computing (HPC) software to protect it from these types of transient processor errors. We develop an open infrastructure to support research work in this area, and we define tools that, in the future, may provide more complete automated and/or semi-automated solutions to support software resiliency on future exascale architectures. Results demonstrate that our approach is feasible, pragmatic in how it can be separated from the software development process, and reasonably efficient (0% to 30% overhead for the Jacobi iteration on common hardware; and 20%, 40%, 26%, and 2% overhead for a randomly selected subset of benchmarks from the Livermore Loops [1]).

  6. Fault-tolerant corrector/detector chip for high-speed data processing

    DOE Patents [OSTI]

    Andaleon, David D.; Napolitano, Jr., Leonard M.; Redinbo, G. Robert; Shreeve, William O.

    1994-01-01

    An internally fault-tolerant data error detection and correction integrated circuit device (10) and a method of operating same. The device functions as a bidirectional data buffer between a 32-bit data processor and the remainder of a data processing system and provides a 32-bit datum is provided with a relatively short eight bits of data-protecting parity. The 32-bits of data by eight bits of parity is partitioned into eight 4-bit nibbles and two 4-bit nibbles, respectively. For data flowing towards the processor the data and parity nibbles are checked in parallel and in a single operation employing a dual orthogonal basis technique. The dual orthogonal basis increase the efficiency of the implementation. Any one of ten (eight data, two parity) nibbles are correctable if erroneous, or two different erroneous nibbles are detectable. For data flowing away from the processor the appropriate parity nibble values are calculated and transmitted to the system along with the data. The device regenerates parity values for data flowing in either direction and compares regenerated to generated parity with a totally self-checking equality checker. As such, the device is self-validating and enabled to both detect and indicate an occurrence of an internal failure. A generalization of the device to protect 64-bit data with 16-bit parity to protect against byte-wide errors is also presented.

  7. Fault-tolerant corrector/detector chip for high-speed data processing

    DOE Patents [OSTI]

    Andaleon, D.D.; Napolitano, L.M. Jr.; Redinbo, G.R.; Shreeve, W.O.

    1994-03-01

    An internally fault-tolerant data error detection and correction integrated circuit device and a method of operating same is described. The device functions as a bidirectional data buffer between a 32-bit data processor and the remainder of a data processing system and provides a 32-bit datum with a relatively short eight bits of data-protecting parity. The 32-bits of data by eight bits of parity is partitioned into eight 4-bit nibbles and two 4-bit nibbles, respectively. For data flowing towards the processor the data and parity nibbles are checked in parallel and in a single operation employing a dual orthogonal basis technique. The dual orthogonal basis increase the efficiency of the implementation. Any one of ten (eight data, two parity) nibbles are correctable if erroneous, or two different erroneous nibbles are detectable. For data flowing away from the processor the appropriate parity nibble values are calculated and transmitted to the system along with the data. The device regenerates parity values for data flowing in either direction and compares regenerated to generated parity with a totally self-checking equality checker. As such, the device is self-validating and enabled to both detect and indicate an occurrence of an internal failure. A generalization of the device to protect 64-bit data with 16-bit parity to protect against byte-wide errors is also presented. 8 figures.

  8. Extreme temperature robust optical sensor designs and fault-tolerant signal processing

    DOE Patents [OSTI]

    Riza, Nabeel Agha; Perez, Frank

    2012-01-17

    Silicon Carbide (SiC) probe designs for extreme temperature and pressure sensing uses a single crystal SiC optical chip encased in a sintered SiC material probe. The SiC chip may be protected for high temperature only use or exposed for both temperature and pressure sensing. Hybrid signal processing techniques allow fault-tolerant extreme temperature sensing. Wavelength peak-to-peak (or null-to-null) collective spectrum spread measurement to detect wavelength peak/null shift measurement forms a coarse-fine temperature measurement using broadband spectrum monitoring. The SiC probe frontend acts as a stable emissivity Black-body radiator and monitoring the shift in radiation spectrum enables a pyrometer. This application combines all-SiC pyrometry with thick SiC etalon laser interferometry within a free-spectral range to form a coarse-fine temperature measurement sensor. RF notch filtering techniques improve the sensitivity of the temperature measurement where fine spectral shift or spectrum measurements are needed to deduce temperature.

  9. REVERSE RADIATIVE SHOCK LASER EXPERIMENTS RELEVANT TO ACCRETING STREAM-DISK IMPACT IN INTERACTING BINARIES

    SciTech Connect (OSTI)

    Krauland, C. M.; Drake, R. P.; Kuranz, C. C.; Huntington, C. M.; Kaczala, D. N.; Klein, S.; Sweeney, R.; Young, R. P.; Keiter, P. A.; Loupias, B.; Falize, E.; Villette, B.; Plewa, T. E-mail: rpdrake@umich.edu

    2013-01-01

    We present the first results from high-energy-density laboratory astrophysics experiments that explore the hydrodynamic and radiative properties of a reverse shock relevant to a cataclysmic variable system. A reverse shock is a shock wave that develops when a freely flowing, supersonic plasma is impeded. In our experiments, performed on the Omega Laser Facility, a laser pulse is used to accelerate plasma ejecta into a vacuum. This flow is directed into an Al plate in front of which a shock forms in the rebounding plasma. The plasma flow is moving fast enough that it is shocked to high enough temperatures that radiative cooling affects the shock structure. These are the first experiments to produce a radiative reverse shock wave.

  10. Magnetization reversal assisted by half antivortex states in nanostructured circular cobalt disks

    SciTech Connect (OSTI)

    Lara, A.; Aliev, F. G.; Dobrovolskiy, O. V.; Prieto, J. L.; Huth, M.

    2014-11-03

    The half antivortex, a fundamental topological structure which determines magnetization reversal of submicron magnetic devices with domain walls, has been suggested also to play a crucial role in spin torque induced vortex core reversal in circular disks. Here, we report on magnetization reversal in circular disks with nanoholes through consecutive metastable states with half antivortices. In-plane anisotropic magnetoresistance and broadband susceptibility measurements accompanied by micromagnetic simulations reveal that cobalt (Co) disks with two and three linearly arranged nanoholes directed at 45° and 135° with respect to the external magnetic field show reproducible step-like changes in the anisotropic magnetoresistance and magnetic permeability due to transitions between different intermediate states mediated by vortices and half antivortices confined to the dot nanoholes and edges, respectively. Our findings are relevant for the development of multi-hole based spintronic and magnetic memory devices.

  11. Multi-channel time-reversal receivers for multi and 1-bit implementations

    DOE Patents [OSTI]

    Candy, James V.; Chambers, David H.; Guidry, Brian L.; Poggio, Andrew J.; Robbins, Christopher L.

    2008-12-09

    A communication system for transmitting a signal through a channel medium comprising digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. In one embodiment a transmitter is adapted to transmit the signal, a multiplicity of receivers are adapted to receive the signal, a digitizer digitizes the signal, and a time-reversal signal processor is adapted to time-reverse the digitized signal. An embodiment of the present invention includes multi bit implementations. Another embodiment of the present invention includes 1-bit implementations. Another embodiment of the present invention includes a multiplicity of receivers used in the step of transmitting the signal through the channel medium.

  12. Ultra-fast magnetic vortex core reversal by a local field pulse

    SciTech Connect (OSTI)

    Rückriem, R.; Albrecht, M.; Schrefl, T.

    2014-02-03

    Magnetic vortex core reversal of a 20-nm-thick permalloy disk with a diameter of 100 nm was studied by micromagnetic simulations. By applying a global out-of-plane magnetic field pulse, it turned out that the final core polarity is very sensitive to pulse width and amplitude, which makes it hard to control. The reason for this phenomenon is the excitation of radial spin waves, which dominate the reversal process. The excitation of spin waves can be strongly suppressed by applying a local field pulse within a small area at the core center. With this approach, ultra-short reversal times of about 15 ps were achieved, which are ten times faster compared to a global pulse.

  13. The elimination of the reverse circulation in thermosiphon solar water heaters

    SciTech Connect (OSTI)

    Prapas, D.E.; Sotiropoulos, B.A. )

    1991-01-01

    Thermosiphon solar water heaters (TSWH), employing either closed or open collector loops, are widely used today to cover a substantial part of the hot water needs, mostly in residential small scale applications. Their cost is lower in comparison to pumped systems, because no pumps, controls etc. are required. However, the storage tank has to be mounted above the collector in order to promote the thermosiphon flow; this could be a serious drawback in some applications. An undesirable characteristic of TSWH is the reverse circulation (RC) of the working liquid when the temperature of the collector is lower than that of the storage tank. The causes of reverse circulation in thermosyphon solar water heaters, the geometry of the systems, and the affects of nocturnal radiative cooling of the collector are discussed. A means of interconnecting collector and tank to drastically reduce reverse circulation is presented.

  14. Simulation of oscillating field current drive on the reversed-field pinch

    SciTech Connect (OSTI)

    Harned, D.S.; Schnack, D.D.; Strauss, H.R.; Nebel, R.A.

    1988-07-01

    Oscillating field current drive on the reversed-field pinch is simulated by using a three-dimensional nonlinear resistive magnetohydrodynamic model in conjunction with a one-dimensional hyper-resistive model. When input from the three-dimensional model is used for fluctuating fields in the hyper-resistive equations, the two models are found to give similar relaxed profiles. Comparisons are made with experiments on the Los Alamos National Laboratory ZT-40M reversed-field pinch device (Nucl. Fusion 25, 1321 (1985)). Simulation results indicate that the oscillation period must be much less than the resistive decay time, but should not be much less than the hyper-resistive relaxation time, in order to maintain reversal without a steady-state driving field.

  15. Reversible gelling culture media for in-vitro cell culture in three-dimensional matrices

    DOE Patents [OSTI]

    An, Yuehuei H.; Mironov, Vladimir A.; Gutowska, Anna

    2000-01-01

    A gelling cell culture medium useful for forming a three dimensional matrix for cell culture in vitro is prepared by copolymerizing an acrylamide derivative with a hydrophilic comonomer to form a reversible (preferably thermally reversible) gelling linear random copolymer in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff, mixing the copolymer with an aqueous solvent to form a reversible gelling solution and adding a cell culture medium to the gelling solution to form the gelling cell culture medium. Cells such as chondrocytes or hepatocytes are added to the culture medium to form a seeded culture medium, and temperature of the medium is raised to gel the seeded culture medium and form a three dimensional matrix containing the cells. After propagating the cells in the matrix, the cells may be recovered by lowering the temperature to dissolve the matrix and centrifuging.

  16. Studies of the pattern and ages of post-metamorphic faults in the Piedmont of Virginia and North Carolina

    SciTech Connect (OSTI)

    Glover, L. III; Costain, J.K.; Coruh, C.

    1988-04-01

    A geologic corridor from the Blue Ridge to the eastern Piedmont of Virginia is integrated into a tectonic model and extrapolated downward 10-15 km by means of seismic reflection and gravity studies. The Blue Ridge appears to be a hinge zone that faced a rift-generated Iapetus Ocean. An eastern continent with an Eocambrian and Cambrian magmatic arc and sediments of the same age, collided with the North American continental margin in the middle and late Ordovician. Subsequent Devono-Mississippian and Mississippian-Permian orogenesis continued to drive thin thrust nappes onto North America. Early Mesozoic rift basins record the beginning of the Atlantic basin and, from Middle Jurassic to Present, the margin of North America was covered by Coastal Plain sediments. Several constrained hypocenters of the central Virginia seismic zone, adjacent to a reflection profile, show an apparent relation to structure. We tentatively conclude that flat and ramp faults formed during Paleozoic nappe emplacement are currently being reactivated. The reactivation may be largely aseismic on the old thrust faults, but seismicity appears to be related to high angle transcurrent faults where new rock breakage may be occurring. 125 refs., 28 figs., 2 tabs.

  17. FLUX ENHANCEMENT IN CROSSFLOW MEMBRANE FILTRATION: FOULING AND IT'S MINIMIZATION BY FLOW REVERSAL

    SciTech Connect (OSTI)

    Shamsuddin Ilias

    2002-03-14

    Fouling problems are perhaps the single most important reason for relatively slow acceptance of ultrafiltration in many areas of chemical and biological processing. To overcome the losses in permeate flux associated with concentration polarization and fouling in cross flow membrane filtration, we investigated the concept of flow reversal as a method to enhance membrane flux in ultrafiltration. Conceptually, flow reversal prevents the formation of stable hydrodynamic and concentration boundary layers at or near the membrane surface. Further more, periodic reversal of the flow direction of the feed stream at the membrane surface results in prevention and mitigation of membrane fouling. Consequently, these advantages are expected to enhance membrane flux significantly. A crossflow membrane filtration unit was designed and built to test the concept of periodic flow reversal for flux enhancement. The essential elements of the system include a crossflow hollow fiber membrane module integrated with a two-way valve to direct the feed flow directions. The two-way valve is controlled by a controller-timer for periodic reversal of flow of feed stream. Another important feature of the system is that with changing feed flow direction, the permeate flow direction is also changed to maintain countercurrent feed and permeate flows for enhanced mass transfer driving force (concentration difference). Bovine serum albumin (BSA) is a well-studied model solute in membrane filtration known for its fouling and concentration polarization capabilities. Laboratory-scale tests on a hollow-fiber ultrafiltration membrane module using BSA solution as feed show that under flow reversal conditions, the permeate flux is significantly enhanced when compared with the conventional unidirectional flow. The flux enhancement is dramatic (by an order of magnitude) with increased feed concentration and operating transmembrane pressure.

  18. Propagation direction reversal of ionization zones in the transition between high and low current magnetron sputtering

    SciTech Connect (OSTI)

    School of Materials Science and Engineering, State Key Lab for Materials Processing and Die & Mold Technology, Huazhong University of Science and Technology, Wuhan 430074, China; Department of Physics, University of California Berkeley, Berkeley, California 94720, USA; Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA; Yang, Yuchen; Liu, Jason; Liu, Lin; Anders, Andr

    2014-12-11

    Past research has revealed the propagation of dense, asymmetric ionization zones in both high and low current magnetron discharges. Here we report about the direction reversal of ionization zone propagation as observed with fast cameras. At high currents, zones move in the E B direction with velocities of 103 to 104 m/s. However at lower currents, ionization zones are observed to move in the opposite, the -E B direction, with velocities ~;; 103 m/s. It is proposed that the direction reversal is associated with the local balance of ionization and supply of neutrals in the ionization zone.

  19. Magnetization Reversal Process of Single Crystal α-Fe Containing a Nonmagnetic Particle

    SciTech Connect (OSTI)

    Li, Yi; Xu, Ben; Hu, Shenyang Y.; Li, Yulan; Li, Qiu-Lin; Liu, Wei

    2015-09-25

    The magnetization reversal process and hysteresis loops in a single crystal α-iron with nonmagnetic particles are simulated in this work based on the Landau-Lifshitz–Gilbert equation. The evolutions of the magnetic domain morphology are studied, and our analyses show that the magnetization reversal process is affected by the interaction between the moving domain wall and the existing nonmagnetic particles. This interaction strongly depends on the size of the particles, and it is found that particles with a particular size contribute the most to magnetic hardening.

  20. Lower-hybrid poloidal current drive for fluctuation reduction in a reversed field pinch

    SciTech Connect (OSTI)

    Uchimoto, E.; Cekic, M.; Harvey, R.W.; Litwin, C.; Prager, S.C.; Sarff, J.S.; Sovinec, C.R.

    1994-06-01

    Current drive using the lower-hybrid slow wave is shown to be a promising candidate for improving confinement properties of a reversed field pinch (RFP). Ray-tracing calculations indicate that the wave will make a few poloidal turns while spiraling radially into a target zone inside the reversal layer. The poloidal antenna wavelength of the lower hybrid wave can be chosen so that efficient parallel current drive will occur mostly in the poloidal direction in this outer region. Three-dimensional resistive magnetohydrodynamic (MHD) computation demonstrates that an additive poloidal current in this region will reduce the magnetic fluctuations and magnetic stochasticity.

  1. Turbulent transport in the Madison Symmetric Torus reversed-field pinch

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

    transport in the Madison Symmetric Torus reversed-field pinch* T. D. Rempel,+ A. F. Almagri, S. Assadi, D. J. Den Hartog, S. A. Hokin, S. C. Prager, J. S. Sarff, W. Shen, K. L. Sidikman, C. W. Spragins, J. C. Sprott, M. R. Stoneking, and E. J. Zita University of Wisconsin, Madison, Wisconsin 53 706 (Received 22 November 1991; accepted 20 February 1992) Measurements of edge turbulence and the associated transport are ongoing in the Madison Symmetric Torus (MST) reversed-field pinch [Fusion

  2. Time-reversal focusing of an expanding soliton gas in disordered replicas

    SciTech Connect (OSTI)

    Fratalocchi, A.; Armaroli, A.; Trillo, S.

    2011-05-15

    We investigate the properties of time reversibility of a soliton gas, originating from a dispersive regularization of a shock wave, as it propagates in a strongly disordered environment. An original approach combining information measures and spin glass theory shows that time-reversal focusing occurs for different replicas of the disorder in forward and backward propagation, provided the disorder varies on a length scale much shorter than the width of the soliton constituents. The analysis is performed by starting from a new class of reflectionless potentials, which describe the most general form of an expanding soliton gas of the defocusing nonlinear Schroedinger equation.

  3. Ion heating and magnetohydrodynamic dynamo fluctuations in the reversed-field pinch

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

    ion heating and magnetohydrodynamic dynamo fluctuations in the reversed-field pinch Earl Scime?) Miodrag Cekic, D. J. Den Hartog, Samuel Hokin, D. J. Holly, and Christopher Watts Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 5.3 706 (Received 8 June 1992; accepted 18 August 1992) Ion temperatures have been measured in the Madison Symmetric Torus (MST) [Dexter et aL, Fusion Technol. 19, 131 ( 199 1 j] reversed-field pinch (RFP) with a five channel charge exchange

  4. MHD computation of feedback of resistive-shell instabilities in the reversed field pinch

    SciTech Connect (OSTI)

    Zita, E.J.; Prager, S.C.; Ho, Y.L.; Schnack, D.D

    1992-05-01

    MHD computation demonstrates that feedback can sustain reversal and reduce loop voltage in resistive-shell reversed field pinch (RFP) plasmas. Edge feedback on {approximately}2R/a tearing modes resonant near axis is found to restore plasma parameters to nearly their levels with a close-fitting conducting shell. When original dynamo modes are stabilized, neighboring tearing modes grow to maintain the RFP dynamo more efficiently. This suggests that experimentally observed limits on RFP pulselengths to the order of the shell time can be overcome by applying feedback to a few helical modes.

  5. Absence of correlation between Sry polymorphisms and XY sex reversal caused by the M.m. domesticus Y chromosome

    SciTech Connect (OSTI)

    Carlisle, C.; Nagamine, C.M. [Vanderbilt Univ., School of Medicine, Nashville, TN (United States)] [Vanderbilt Univ., School of Medicine, Nashville, TN (United States); Winkinig, H.; Weichenhan, D. [Medizinische Universitaet Zu Luebeck (Germany)] [Medizinische Universitaet Zu Luebeck (Germany)

    1996-04-01

    Mus musculus domesticus Y chromosomes (Y{sup DOM} Chrs) vary in their ability to induce testes in the strain C57BL/6J. In severe cases, XY females develop (XY{sup DOM} sex reversal). To identify the molecular basis for the sex reversal, a 2.7-kb region of Sry, the testis-determining gene, was sequenced from Y{sup DOM} Chrs linked to normal testis determination, transient sex reversal, and severe sex reversal. Four mutations were identified. However, no correlation exists between these mutations and severity of XY{sup DOM} sex reversal. RT-PCR identified Sry transcripts in XY{sup DOM} sex-reversed fetal gonads at 11 d.p.c., the age when Sry is hypothesized to function. In addition, no correlation exists between XY{sup DOM} sex reversal and copy numbers of pSx1, a Y-repetitive sequence whose deletion is linked to XY sex reversal. We conclude that SRY protein variants, blockade of Sry transcription, and deletion of pSx1 sequences are not the underlying causes of XY{sup DOM} sex reversal. 63 refs., 6 figs., 6 tabs.

  6. A field-reversed magnetic configuration and applications of high-temperature FRC plasma

    SciTech Connect (OSTI)

    Ryzhkov, S. V.

    2011-12-15

    As applied to a tokomak, a magnetic trap for confinement of a plasma with an inverted field or a magnetic field reversed configuration (FRC) is one of the most promising alternatives of the systems with high {beta}. A brief review of the latest data on FRC and potential directions of using such configurations in addition to energy generation in thermonuclear reactors (TNRs) is proposed.

  7. Confinement analyses of the high-density field-reversed configuration plasma in the field-reversed configuration experiment with a liner

    SciTech Connect (OSTI)

    Zhang Shouyin; Intrator, T.P.; Wurden, G.A.; Waganaar, W.J.; Taccetti, J.M.; Renneke, R.; Grabowski, C.; Ruden, E.L.

    2005-05-15

    The focus of the field-reversed configuration (FRC) experiment with a liner (FRX-L) is the formation of a target FRC plasma for magnetized target fusion experiments. An FRC plasma with density of 10{sup 23} m{sup -3}, total temperature in the range of 150-300 eV, and a lifetime of {approx_equal}20 {mu}s is desired. Field-reversed {theta}-pinch technology is used with programed cusp fields at {theta}-coil ends to achieve non-tearing field line reconnections during FRC formation. Well-formed FRCs with density between (2-4)x10{sup 22} m{sup -3}, lifetime in the range of 15-20 {mu}s, and total temperature between 300-500 eV are reproducibly created. Key FRC parameters have standard deviation in the mean of 10% during consecutive shots. The FRCs are formed at 50 mTorr deuterium static fill using 2 kG net reversed bias field inside the {theta}-coil confinement region, with external main field unexpectedly ranging between 15-30 kG. The high-density FRCs confinement properties are approximately in agreement with empirical scaling laws obtained from previous experiments with fill pressure mostly less than 20 mTorr. Analyses in this paper reveal that reducing the external main field modulation and/or extending the {theta}-coil length in the FRX-L device are critical in achieving higher FRC parameters for application in magnetized target fusion.

  8. Fault-related CO2 degassing, geothermics, and fluid flow in southern California basins---Physiochemical evidence and modeling

    SciTech Connect (OSTI)

    Boles, James R.; Garven, Grant

    2015-08-04

    Our studies have had an important impact on societal issues. Experimental and field observations show that CO2 degassing, such as might occur from stored CO2 reservoir gas, can result in significant stable isotopic disequilibrium. In the offshore South Ellwood field of the Santa Barbara channel, we show how oil production has reduced natural seep rates in the area, thereby reducing greenhouse gases. Permeability is calculated to be ~20-30 millidarcys for km-scale fault-focused fluid flow, using changes in natural gas seepage rates from well production, and poroelastic changes in formation pore-water pressure. In the Los Angeles (LA) basin, our characterization of formation water chemistry, including stable isotopic studies, allows the distinction between deep and shallow formations waters. Our multiphase computational-based modeling of petroleum migration demonstrates the important role of major faults on geological-scale fluid migration in the LA basin, and show how petroleum was dammed up against the Newport-Inglewood fault zone in a “geologically fast” interval of time (less than 0.5 million years). Furthermore, these fluid studies also will allow evaluation of potential cross-formational mixing of formation fluids. Lastly, our new study of helium isotopes in the LA basin shows a significant leakage of mantle helium along the Newport Inglewood fault zone (NIFZ), at flow rates up to 2 cm/yr. Crustal-scale fault permeability (~60 microdarcys) and advective versus conductive heat transport rates have been estimated using the observed helium isotopic data. The NIFZ is an important deep-seated fault that may crosscut a proposed basin decollement fault in this heavily populated area, and appears to allow seepage of helium from the mantle sources about 30 km beneath Los Angeles. The helium study has been widely cited in recent weeks by the news media, both in radio and on numerous web sites.

  9. A novel micro-Raman technique to detect and characterize 4H-SiC stacking faults

    SciTech Connect (OSTI)

    Piluso, N. Camarda, M.; La Via, F.

    2014-10-28

    A novel Micro-Raman technique was designed and used to detect extended defects in 4H-SiC homoepitaxy. The technique uses above band-gap high-power laser densities to induce a local increase of free carriers in undoped epitaxies (n < 10{sup 16} at/cm{sup −3}), creating an electronic plasma that couples with the longitudinal optical (LO) Raman mode. The Raman shift of the LO phonon-plasmon-coupled mode (LOPC) increases as the free carrier density increases. Crystallographic defects lead to scattering or recombination of the free carriers which results in a loss of coupling with the LOPC, and in a reduction of the Raman shift. Given that the LO phonon-plasmon coupling is obtained thanks to the free carriers generated by the high injection level induced by the laser, we named this technique induced-LOPC (i-LOPC). This technique allows the simultaneous determination of both the carrier lifetime and carrier mobility. Taking advantage of the modifications on the carrier lifetime induced by extended defects, we were able to determine the spatial morphology of stacking faults; the obtained morphologies were found to be in excellent agreement with those provided by standard photoluminescence techniques. The results show that the detection of defects via i-LOPC spectroscopy is totally independent from the stacking fault photoluminescence signals that cover a large energy range up to 0.7 eV, thus allowing for a single-scan simultaneous determination of any kind of stacking fault. Combining the i-LOPC method with the analysis of the transverse optical mode, the micro-Raman characterization can determine the most important properties of unintentionally doped film, including the stress status of the wafer, lattice impurities (point defects, polytype inclusions) and a detailed analysis of crystallographic defects, with a high spectral and spatial resolution.

  10. The importance of input variables to a neural network fault-diagnostic system for nuclear power plants

    SciTech Connect (OSTI)

    Lanc, T.L.

    1992-01-01

    This thesis explores safety enhancement for nuclear power plants. Emergency response systems currently in use depend mainly on automatic systems engaging when certain parameters go beyond a pre-specified safety limit. Often times the operator has little or no opportunity to react since a fast scram signal shuts down the reactor smoothly and efficiently. These accidents are of interest to technical support personnel since examining the conditions that gave rise to these situations help determine causality. In many other cases an automated fault-diagnostic advisor would be a valuable tool in assisting the technicians and operators to determine what just happened and why.

  11. The importance of input variables to a neural network fault-diagnostic system for nuclear power plants

    SciTech Connect (OSTI)

    Lanc, T.L.

    1992-12-31

    This thesis explores safety enhancement for nuclear power plants. Emergency response systems currently in use depend mainly on automatic systems engaging when certain parameters go beyond a pre-specified safety limit. Often times the operator has little or no opportunity to react since a fast scram signal shuts down the reactor smoothly and efficiently. These accidents are of interest to technical support personnel since examining the conditions that gave rise to these situations help determine causality. In many other cases an automated fault-diagnostic advisor would be a valuable tool in assisting the technicians and operators to determine what just happened and why.

  12. Solid-State Fault Current Limiter Development : Design and Testing Update of a 15kV SSCL Power Stack

    SciTech Connect (OSTI)

    Dr. Ram Adapa; Mr. Dante Piccone

    2012-04-30

    ABSTRACT The Solid-State Fault Current Limiter (SSCL) is a promising technology that can be applied to utility power delivery systems to address the problem of increasing fault currents associated with load growth. As demand continues to grow, more power is added to utility system either by increasing generator capacity or by adding distributed generators, resulting in higher available fault currents, often beyond the capabilities of the present infrastructure. The SSCL is power-electronics based equipment designed to work with the present utility system to address this problem. The SSCL monitors the line current and dynamically inserts additional impedance into the line in the event of a fault being detected. The SSCL is based on a modular design and can be configured for 5kV through 69kV systems at nominal current ratings of 1000A to 4000A. Results and Findings This report provides the final test results on the development of 15kV class SSCL single phase power stack. The scope of work included the design of the modular standard building block sub-assemblies, the design and manufacture of the power stack and the testing of the power stack for the key functional tests of continuous current capability and fault current limiting action. Challenges and Objectives Solid-State Current Limiter technology impacts a wide spectrum of utility engineering and operating personnel. It addresses the problems associated with load growth both at Transmission and Distribution class networks. The design concept is pioneering in terms of developing the most efficient and compact power electronics equipment for utility use. The initial test results of the standard building blocks are promising. The independent laboratory tests of the power stack are promising. However the complete 3 phase system needs rigorous testing for performance and reliability. Applications, Values, and Use The SSCL is an intelligent power-electronics device which is modular in design and can provide current

  13. Segregation At Stacking Faults Within The ?' Phase Of Two Ni-base Superalloys Following Intermediate Temperature Creep

    SciTech Connect (OSTI)

    Viswanathan, G. B.; Shi, R.; Genc, Arda; Vorontsov, V. A.; Kovarik, Libor; Rae, C.M. F.; Mills, M. J.

    2015-01-01

    Using state-of-the-art energy dispersive spectroscopy, it has been established for the first time that there exists significant compositional variation (enrichment of Co and Cr and deficiency of Ni and Al) associated with superlattice intrinsic stacking faults created in the ordered ?' precipitates following intermediate temperature deformation of two commercial superalloys. The results indicate that long range diffusion of these elements is intimately involved in the precipitate shearing process and is therefore closely linked to the time-dependent deformation of the alloys.

  14. Evaluation of chiller modeling approaches and their usability for fault detection

    SciTech Connect (OSTI)

    Sreedharan, Priya

    2001-05-01

    Selecting the model is an important and essential step in model based fault detection and diagnosis (FDD). Several factors must be considered in model evaluation, including accuracy, training data requirements, calibration effort, generality, and computational requirements. All modeling approaches fall somewhere between pure first-principles models, and empirical models. The objective of this study was to evaluate different modeling approaches for their applicability to model based FDD of vapor compression air conditioning units, which are commonly known as chillers. Three different models were studied: two are based on first-principles and the third is empirical in nature. The first-principles models are the Gordon and Ng Universal Chiller model (2nd generation), and a modified version of the ASHRAE Primary Toolkit model, which are both based on first principles. The DOE-2 chiller model as implemented in CoolTools{trademark} was selected for the empirical category. The models were compared in terms of their ability to reproduce the observed performance of an older chiller operating in a commercial building, and a newer chiller in a laboratory. The DOE-2 and Gordon-Ng models were calibrated by linear regression, while a direct-search method was used to calibrate the Toolkit model. The ''CoolTools'' package contains a library of calibrated DOE-2 curves for a variety of different chillers, and was used to calibrate the building chiller to the DOE-2 model. All three models displayed similar levels of accuracy. Of the first principles models, the Gordon-Ng model has the advantage of being linear in the parameters, which allows more robust parameter estimation methods to be used and facilitates estimation of the uncertainty in the parameter values. The ASHRAE Toolkit Model may have advantages when refrigerant temperature measurements are also available. The DOE-2 model can be expected to have advantages when very limited data are available to calibrate the model, as

  15. Elasticity-induced force reversal between active spinning particles in dense passive media

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

    Aragones, J. L.; Steimel, J. P.; Alexander-Katz, A.

    2016-04-26

    The self-organization of active particles is governed by their dynamic effective interactions. Such interactions are controlled by the medium in which such active agents reside. Here we study the interactions between active agents in a dense non-active medium. Our system consists of actuated, spinning, active particles embedded in a dense monolayer of passive, or non-active, particles. We demonstrate that the presence of the passive monolayer alters markedly the properties of the system and results in a reversal of the forces between active spinning particles from repulsive to attractive. The origin of such reversal is due to the coupling between themore » active stresses and elasticity of the system. Finally, this discovery provides a mechanism for the interaction between active agents in complex and structured media, opening up opportunities to tune the interaction range and directionality via the mechanical properties of the medium.« less

  16. Evaluate fundamental approaches to longwall dust control: Subprogram F, Reversed drum rotation

    SciTech Connect (OSTI)

    Ludlow, J.; Kelly, J.; Ruggieri, S.

    1990-05-01

    In longwall mining, a significant portion of the shearer operator's dust exposure is caused by dust generated during loading. With the conventional direction of shearer drum rotation, loading efficiency is usually poor due to obstructions caused by the ranging arms and the cowl support arms. By reversing the normal direction of rotation, however, the arms no longer provide an obstruction. This results in improved loading efficiency and reduced dust generation. This report describes the reversed drum rotation concept and presents the results of a field survey and underground evaluation conducted to prove its feasibility and to measure its dust control benefits. Through this effort, the technique was shown to be feasible from both a mining and mechanical standpoint. During the underground test, it reduced dust levels near the shearer operator's positions by about 85%. 20 figs., 4 tabs.

  17. Advanced dimensional inspection for the reverse engineering of power plant equipment

    SciTech Connect (OSTI)

    Kotteakos, B.; Ball, K.A.

    1996-12-31

    Forced outages and critical path situations often leave electric utilities with very few options other than the OEM. What does the utility do when faced with the situation of long lead time or obsolete items necessary to bring units back on-line, or off load restrictions. At Southern California Edison Company (SCE), a proactive approach to the reverse engineering and inspection process was undertaken to reduce the effects of similar situations. Advances in dimensional measurement technology have afforded the authors` company a cost effective method for obtaining the necessary inspection data to remanufacture certain items. This paper identifies equipment utilized by SCE for the reverse engineering and inspection of turbine and turbine related components and their typical applications in the power generation industry.

  18. Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

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

    Weber, T. E.; Intrator, T. P.; Smith, R. J.

    2015-04-29

    The injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. Our approach was found to significantly improve FRC formation in a conical θ-pinch, resulting in a ~350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and highermore » temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.« less

  19. Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

    SciTech Connect (OSTI)

    Weber, T. E. Intrator, T. P.; Smith, R. J.

    2015-04-15

    Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ∼350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.

  20. Power balance in a high-density field reversed configuration plasma

    SciTech Connect (OSTI)

    Renneke, R. M.; Intrator, T. P.; Hsu, S. C.; Wurden, G. A.; Waganaar, W. J.; Ruden, E. L.; Grabowski, T. C.

    2008-06-15

    A global power balance analysis has been performed for the Field Reversed Experiment with Liner high density (>5x10{sup 22} m{sup -3}) field reversed configuration (FRC) plasma. The analysis was based on a zero-dimensional power balance model [D. J. Rey and M. Tuszewski, Phys. Fluids 27, 1514 (1984)]. The key findings are as follows. First, the percentage of radiative losses relative to total loss is an order of magnitude lower than previous lower density FRC experiments. Second, Ohmic heating was found to correlate with the poloidal flux trapping at FRC formation, suggesting that poloidal flux dissipation is primarily responsible for plasma heating. Third, high density FRCs analyzed in this work reinforce the low-density adiabatic scaling, which shows that particle confinement time and flux confinement time are approximately equal.