Sample records for magnet ac synchronous

  1. A Robust Hybrid Current Control for Permanent Magnet Synchronous Motor Drive

    E-Print Network [OSTI]

    Boyer, Edmond

    --Recently, the Permanent Magnet Synchronous Motor (PMSM) find a widespread utilization in modern adjustable AC drives. Comparisons using simulations on a 0.9-kW PMSM confirm that the proposed hybrid current controller gives of the stator current, obtained by using a fast Fourier transform, are used for comparison purposes. Index Terms--PMSM

  2. Cancellation of TorqueRipple Due to Nonidealitiesof PermanentMagnet SynchronousMachine Drives

    E-Print Network [OSTI]

    Chapman, Patrick

    -magnet synchronous application than the predecessors. Further, the technique is machine (PMSM) drives dictates

  3. Magnetic levitation configuration incorporating levitation, guidance and linear synchronous motor

    DOE Patents [OSTI]

    Coffey, H.T.

    1993-10-19T23:59:59.000Z

    A propulsion and suspension system for an inductive repulsion type magnetically levitated vehicle which is propelled and suspended by a system which includes propulsion windings which form a linear synchronous motor and conductive guideways, adjacent to the propulsion windings, where both combine to partially encircling the vehicle-borne superconducting magnets. A three phase power source is used with the linear synchronous motor to produce a traveling magnetic wave which in conjunction with the magnets propel the vehicle. The conductive guideway combines with the superconducting magnets to provide for vehicle levitation. 3 figures.

  4. Permanent magnet assisted synchronous reluctance motor, design and performance improvement

    E-Print Network [OSTI]

    Niazi, Peyman

    2006-04-12T23:59:59.000Z

    Recently, permanent magnet assisted (PMa)-synchronous reluctance motors (SynRM) have been considered as a possible alternative motor drive for high performance applications. In order to have an efficient motor drive, performing of three steps...

  5. Optimal Current Waveforms for Brushless Permanent Magnet Motors

    E-Print Network [OSTI]

    ;1 Introduction We consider the problem of controlling an AC permanent magnet synchronous motor (PMSM) by choosing

  6. SUPER HIGH-SPEED MINIATURIZED PERMANENT MAGNET SYNCHRONOUS MOTOR

    E-Print Network [OSTI]

    Wu, Thomas

    with the design of permanent magnet synchronous motors (PMSM) to operate at super-high speed with high efficiency. The designed and fabricated PMSM was successfully tested to run upto 210,000 rpm The designed PMSM has 2000 W concept of electrical machines. After that, the modeling of PMSM for dynamic simulation is provided

  7. Permanent Magnets Synchronous Machines Faults Detection and Identification

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for permanent magnet synchronous machines (PMSM). Two main faults occurring on these machines are identified of the PMSM is devel- oped and simulated using Matlab Simulink. The model enables simulating nominal and faulty PMSM behavior, with several stages of degradation, and is supported by tests results. Specific

  8. Robust Timing Synchronization for AC-OFDM Based Optical Wireless Communications

    E-Print Network [OSTI]

    Ranjha, Bilal A; Kavehrad, Mohsen; Deng, Peng

    2015-01-01T23:59:59.000Z

    Visible light communications (VLC) have recently attracted a growing interest and can be a potential solution to realize indoor wireless communication with high bandwidth capacity for RF-restricted environments such as airplanes and hospitals. Optical based orthogonal frequency division multiplexing (OFDM) systems have been proposed in the literature to combat multipath distortion and intersymbol interference (ISI) caused by multipath signal propagation. In this paper, we present a robust timing synchronization scheme suitable for asymmetrically clipped (AC) OFDM based optical intensity modulated direct detection (IM/DD) wireless systems. Our proposed method works perfectly for ACO-OFDM, Pulse amplitude modulated discrete multitone (PAM-DMT) and discrete Hartley transform (DHT) based optical OFDM systems. In contrast to existing OFDM timing synchronization methods which are either not suitable for AC OFDM techniques due to unipolar nature of output signal or perform poorly, our proposed method is suitable for...

  9. Control strategy of a variable speed wind turbine with multipole permanent magnet synchronous generator

    E-Print Network [OSTI]

    values. Keywords: permanent magnet synchronous generator, variable speed wind turbine, direct driven wind). A multipole synchronous generator connected to a power converter can operate at low speeds, so that a gear canControl strategy of a variable speed wind turbine with multipole permanent magnet synchronous

  10. Design of a High Performance Ferrite Magnet-Assisted Synchronous Reluctance Motor for an

    E-Print Network [OSTI]

    Paderborn, Universität

    Design of a High Performance Ferrite Magnet- Assisted Synchronous Reluctance Motor for an Electric) ferrite-based permanent magnet-assisted synchronous reluctance motor has been designed for an electric vehicle application. The design steps are outlined. Ferrite magnets have been chosen over conventional Nd

  11. Harmonic mixing in two coupled qubits: quantum synchronization via ac drives

    E-Print Network [OSTI]

    S. E. Savel'ev; Z. Washington; A. M. Zagoskin; M. J. Everitt

    2012-10-12T23:59:59.000Z

    Simulating a system of two driven coupled qubits, we show that the time-averaged probability to find one driven qubit in its ground or excited state can be controlled by an ac drive in the second qubit. Moreover, off-diagonal elements of the density matrix responsible for quantum coherence can also be controlled via driving the second qubit, i.e., quantum coherence can be enhanced by appropriate choice of the bi-harmonic signal. Such a dynamic synchronization of two differently driven qubits has an analogy with harmonic mixing of Brownian particles forced by two signals through a substrate. Nevertheless, the quantum synchronization in two qubits occurs due to multiplicative coupling of signals in the qubits rather than via a nonlinear harmonic mixing for a classical nano-particle.

  12. Dynamic Motor Parameter Identification for High Speed Flux Weakening Operation of Brushless Permanent Magnet Synchronous Machines

    E-Print Network [OSTI]

    Szabados, Barna

    performance torque control. Advanced high speed salient-pole synchronous machine drives use vector control Permanent Magnet Synchronous Machines Abstract: An experimental investigation is conducted to determine the behaviour of brushless PM synchronous machine parameters in the high speed flux weakening operating range

  13. ac magnetic field: Topics by E-print Network

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

    contract No. DE-AC02-76CH00016. Abstract A common coil design concept for 2-in-1 superconduct- ing Gupta, Ramesh 126 Anisotropy of magnetic emulsions induced by magnetic and...

  14. ac magnetic fields: Topics by E-print Network

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

    contract No. DE-AC02-76CH00016. Abstract A common coil design concept for 2-in-1 superconduct- ing Gupta, Ramesh 126 Anisotropy of magnetic emulsions induced by magnetic and...

  15. Modelling and design of an eddy current coupling for slip-synchronous permanent magnet wind generators.

    E-Print Network [OSTI]

    Mouton, Zac

    2013-01-01T23:59:59.000Z

    ??ENGLISH ABSTRACT: Slip-synchronous permanent magnet generators (SS-PMG) is a recently proposed direct-grid connected direct-drive generator topology for wind power applications. It combines a permanent magnet (more)

  16. Abstract--Linear electrical loading system (LELS) driven by electrical cylinder with permanent magnet synchronous

    E-Print Network [OSTI]

    Yao, Bin

    magnet synchronous motor (PMSM) offers several advantages of high transmission efficiency and high cylinder driven by permanent magnet synchronous motor (PMSM). Though direct-drive linear motors has some to direct-drive linear motor, the solution of electrical cylinder with PMSM has larger output force

  17. IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 55, NO. 2, FEBRUARY 2008 501 Permanent Magnet Synchronous Machine

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Terms--Direct control, hybrid dynamic systems, perma- nent magnet synchronous machine (PMSM), physical magnet synchronous machine (PMSM) and a two-level voltage inverter (Fig. 1). The PMSM constitutes variables) so hybrid control strategies apply adequately. For PMSM drives, vector control has been

  18. Transient Peak Currents in Permanent Magnet Synchronous Motors

    E-Print Network [OSTI]

    Paderborn, Universität

    synchronous motors (PMSM) became more and more popular for these applications. The performance of PMSM drives not be triggered at motor operating points, for which the SSC current behavior will damage the PMSM drive. An analysis of PMSM behavior with

  19. Estimation of Saturation of Permanent-Magnet Synchronous Motors Through an Energy-Based Model

    E-Print Network [OSTI]

    Jebai, AlKassem; Martin, Philippe; Rouchon, Pierre

    2011-01-01T23:59:59.000Z

    We propose a parametric model of the saturated Permanent-Magnet Synchronous Motor (PMSM) together with an estimation method of the magnetic parameters. The model is based on an energy function which simply encompasses the saturation effects. Injection of fast-varying pulsating voltages and measurements of the resulting current ripples then permit to identify the magnetic parameters by linear least squares. Experimental results on a surface-mounted PMSM and an interoir magnet PMSM illustrate the relevance of the approach.

  20. Dynamic performance of static and synchronous compensators at an HVDC inverter bus in a very weak AC system

    SciTech Connect (OSTI)

    Nayak, O.B.; Gole, A.M. (Univ. of Manitoba, Winnipeg (Canada)); Chapman, D.G.; Davies, J.B. (Manitoba Hydro, Winnipeg (Canada))

    1994-08-01T23:59:59.000Z

    This paper discusses the performance of dynamic voltage control devices at the inverters of very weak ac systems. The types of compensation considered are: (a) static var compensator (SVC), (b) synchronous compensator (SC), (c) a mix of the two and (d) fixed capacitors. Although the primary purpose of these compensators is to control voltage at the ac bus, their dynamic performance during system disturbances is a very important factor. The investigation includes the behavior of the various voltage control options under ac and dc disturbances. The paper shows that the SVC has the fastest response for load rejection type of overvoltages, but can cause serious problems with recovery during undervoltages caused by single phase faults. The CIGRE benchmark model for HVdc control studies has been modified and used in this study. In particular the effect of local load has been included.

  1. Minimizing Wheel Slip in Railway Locomotives with Coupled Permanent Magnet Synchronous Motors

    E-Print Network [OSTI]

    Shayak Bhattacharjee

    2015-01-17T23:59:59.000Z

    In this work I consider control strategies of permanent magnet synchronous motors in which the back-emf signal from the motor is used to achieve commutation of the six step driving circuit. I show that if the strategy is modified to connect multiple motors in a cyclic chain, then a collective synchronized state is favoured. The stability of this state can be exploited in the bogies of a railway locomotive to automatically terminate wheel slipping episodes.

  2. Power-Factor and Torque Calculation with Consideration of Cross Saturation of the Interior Permanent Magnet Synchronous Motor with

    E-Print Network [OSTI]

    Tolbert, Leon M.

    motor of a hybrid electric vehicle. I. INTRODUCTION The interior permanent magnet synchronous motor for application in a hybrid electric vehicle. The BFE structure enables the motor to control the magnitude Permanent Magnet Synchronous Motor with Brushless Field Excitation Seong Taek Lee1,2 , Timothy A. Burress1

  3. Control Realization for an Interior Permanent Magnet Synchronous Motor (IPMSM) in Automotive Drive Trains

    E-Print Network [OSTI]

    Paderborn, Universität

    Control Realization for an Interior Permanent Magnet Synchronous Motor (IPMSM) in Automotive Drive Trains Wilhelm Peters, Tobias Huber, Joachim Böcker Power Electronics and Electrical Drives, Paderborn automotive traction drives are a wide speed range, a wide constant-power operation range and high efficiency

  4. Design of optimal digital controller for stable super-high-speed permanent-magnet synchronous

    E-Print Network [OSTI]

    Wu, Thomas

    collaborative design scheme of a super-high-speed permanent-magnet synchronous motor (PMSM) and its digital stability and performance. Since the systematic design of the PMSM can ensure its stability over the full the efficiency and performance of the PMSM. The unique feature in the proposed optimal V/f control is its design

  5. Multi-criteria based design approach of multiphase permanent magnet low speed synchronous machines

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    dedicated to multiphase Permanent Magnet Synchronous Machines (PMSM) supplied by Pulse Width Modulation to use PWM VSI for supplying high power propulsion machines [1]. The induction machines and the PMSM can be easily considered in this instance since the constraint on the reactive power does not apply [2]. PMSM

  6. Direct torque control of permanent magnet synchronous motors with non-sinusoidal back-EMF

    E-Print Network [OSTI]

    Ozturk, Salih Baris

    2009-05-15T23:59:59.000Z

    torque control of permanent magnet synchronous motor (PMSM) with sinusoidal back-EMF is discussed in detail. Secondly, the proposed two-phase conduction mode for DTC of BLDC motors is introduced in the constant torque region. In this control scheme, only...

  7. Enhanced synchronization in an array of spin torque nano oscillators in the presence of oscillating external magnetic field

    E-Print Network [OSTI]

    B. Subash; V. K. Chandrasekar; M. Lakshmanan

    2014-12-23T23:59:59.000Z

    We demonstrate that the synchronization of an array of electrically coupled spin torque nano-oscillators (STNO) modelled by Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation can be enhanced appreciably in the presence of a common external microwave magnetic field. The applied microwave magnetic field stabilizes and enhances the regions of synchronization in the parameter space of our analysis, where the oscillators are exhibiting synchronized oscillations thereby emitting improved microwave power. To characterize the synchronized oscillations we have calculated the locking range in the domain of external source frequency.

  8. Performance improvement of permanent magnet ac motors

    E-Print Network [OSTI]

    Parsa, Leila

    2005-08-29T23:59:59.000Z

    .????????????????....????.. 19 B. Background............??..?????.??.?????...?.?.... 20 C. Comparing BLDC Motor and PMSM???????????... 24 D. Harmonic Spectrum of MMF in Machines with Non-sinusoidal Winding Distribution??????????????????.. 26 ix TABLE............................................................................ 58 H. Conclusion??????????????????????. 68 III FAULT TOLERANT OPERATION OF PERMANENT MAGNET MOTOR DRIVES?????????????????????? 69 A. Introduction.????????????????....???.?. 69 B. Fault Tolerant Operation of Five-Phase PMSM...

  9. FLUXCAP: A flux-coupled ac/dc magnetizing device

    E-Print Network [OSTI]

    Gopman, Daniel B; Kent, Andrew D

    2012-01-01T23:59:59.000Z

    We report on an instrument for applying ac and dc magnetic fields by capturing the flux from a rotating permanent magnet and projecting it between two adjustable pole pieces. This can be an alternative to standard electromagnets for experiments with small samples or in probe stations in which an applied magnetic field is needed locally, with advantages that include a compact form-factor, very low power requirements and dissipation as well as fast field sweep rates. This flux capture instrument (FLUXCAP) can produce fields from -400 to +400 mT, with field resolution less than 1 mT. It generates static magnetic fields as well as ramped fields, with ramping rates as high as 10 T/s. We demonstrate the use of this apparatus for studying the magnetotransport properties of spin-valve nanopillars, a nanoscale device that exhibits giant magnetoresistance.

  10. The role of eddy currents and nanoparticle size on AC magnetic fieldinduced reflow in solder/magnetic nanocomposites

    E-Print Network [OSTI]

    McHenry, Michael E.

    facilitate solder reflow in AC magnetic fields. We compare power loss in a solder composite sample with MNP, for smaller samples, power loss is not sufficient to realize solder reflow temperature. Additional heating can powders (Power loss in magnetic

  11. Self-consistent magnetic properties of magnetite tracers optimized for magnetic particle imaging measured by ac susceptometry,

    E-Print Network [OSTI]

    Krishnan, Kannan M.

    Self-consistent magnetic properties of magnetite tracers optimized for magnetic particle imaging measured by ac susceptometry, magnetorelaxometry and magnetic particle spectroscopy Frank Ludwig a , Hilke. Krishnan b,n a Institute of Electrical Measurement and Fundamental Electrical Engineering, TU Braunschweig

  12. Abstract--In this paper, the performances of a hybrid ex-citation flux switching permanent magnets synchronous

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    High efficiency, high power factor, high Tor- que/Volume ratio, high torque and speed operating points solution [3] while it combines the advantages of the permanent magnets machines and wound rotor synchronous iron parts, classical armature wind- ings and additional DC excitation coils situated above

  13. Abstract--A variable speed wind turbine is presented in this paper, where multiple permanent magnet synchronous

    E-Print Network [OSTI]

    Chen, Zhe

    1 Abstract--A variable speed wind turbine is presented in this paper, where multiple permanent magnet synchronous generators (MPMSGs) drive-train configuration is employed in the wind turbine of this variable speed wind turbine based on multiple generators drive-train configuration. Index Terms--Wind power

  14. Abstract--This paper discusses an optimum design of an ultra high-speed permanent-magnet synchronous motor

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    -magnet synchronous motor (PMSM), which is applied to a supercharger of an automotive engine. Although the motor (PMSM), which is specifically applied to the electric supercharger of the automotive engines. Although the PMSM is operated by an inverter with a 12-V DC bus voltage for an adjustable-speed drive, it must

  15. Design of low-power permanent-magnet synchronous motor for use in high-density heat pump

    E-Print Network [OSTI]

    Jenicek, David P. (David Pierre)

    2011-01-01T23:59:59.000Z

    An analytical model for the functionality of a permanent-magnet synchronous motor is developed. Taking as input a specific geometry, it predicts steady-state losses of a design at an average rate of 0.85 seconds per analysis, ...

  16. Abstract-During the design of permanent magnet synchronous machines (PMSM), the first step that engineers have to do,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Abstract-During the design of permanent magnet synchronous machines (PMSM), the first step. Fractional- slots (FS)-PMSM offers several advantages and have been focused by a lot of researches. However to their numerous advantages, PMSM have found wide attention in the research and industrial areas. For instance

  17. Computer Based Motor Parameter Determination for High Speed Operation of Permanent Magnet Synchronous Machines

    E-Print Network [OSTI]

    Szabados, Barna

    Synchronous Machines B. Szabados and U. Schaible McMaster University 1280 Main St. W., Hamilton, Ontario PM synchronous machine parameters in the high speed operating range. The theory and real interior PM synchronous machine at up to 8000 rpm. Results are presented which show a significant variation

  18. A Structure-Preserving Model and Sufficient Condition for Frequency Synchronization of Lossless Droop Inverter-Based AC Networks

    SciTech Connect (OSTI)

    Ainsworth, Nathan G [ORNL] [ORNL; Grijalva, Prof. Santiago [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta

    2013-01-01T23:59:59.000Z

    This paper presents a new method for analysis of frequency synchronization of lossless power networks whose sources are frequency-droop controlled inverters. Unlike most existing approaches, our method focuses on the interaction between inverters and the network to provide new physical insight into how those interactions create frequency synchronization. We introduce two structure-preserving models of such a network (one bus-oriented and one line-oriented), and show that frequency synchronization corresponds to convergence to an equilibrium of these models. We derive a necessary condition for existence of such equilibria, and determine a simple test for their local stability. Finally, we introduce a sufficient condition for frequency synchronization of such networks, and show that it consists of a set of local criteria which can each be determined from local measurements.

  19. A Novel Current Angle Control Scheme in a Current Source Inverter Fed Permanent Magnet Synchronous Motor Drive for Automotive Applications

    SciTech Connect (OSTI)

    Tang, Lixin [ORNL] [ORNL; Su, Gui-Jia [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    This paper describes a novel speed control scheme to operate a current source inverter (CSI) driven surface-mounted permanent magnet synchronous machine (SPMSM) for hybrid electric vehicles (HEVs) applications. The idea is to use the angle of the current vector to regulate the rotor speed while keeping the two dc-dc converter power switches on all the time to boost system efficiency. The effectiveness of the proposed scheme was verified with a 3 kW CSI-SPMSM drive prototype.

  20. Optimal Control of Permanent-MagnetAC MachineDrives with a Novel Multiple ReferenceFrame Estimator/Regulator

    E-Print Network [OSTI]

    Chapman, Patrick

    , IN 47907-1285 Abstract- With appropriate current waveforms, permanent- magnet synchronous machine (PMSM are used to validate the work. I. INTRODUCTION PMSM drives have recently been a topic of intense research

  1. Abstract --This paper presents a theoretical approach as far as faulty Permanent Magnet Synchronous Machines

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Synchronous Machines (PMSM) are concerned. The knowledge of PMSM's behavior under inter-turn fault is very detection often require faulty models. The aim of this paper is to develop a dynamical model of a PMSM under into account of different winding distributions. I. INTRODUCTION One way to study PMSM under inter-turn short

  2. AC transport in p-Ge/GeSi quantum well in high magnetic fields

    SciTech Connect (OSTI)

    Drichko, I. L.; Malysh, V. A.; Smirnov, I. Yu.; Golub, L. E.; Tarasenko, S. A. [A.F. Ioffe Physical Technical Institute of Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation); Suslov, A. V. [National High Magnetic Field Laboratory, Tallahassee, FL 32310 (United States); Mironov, O. A. [Warwick SEMINANO R and D Center, University of Warwick Science Park, Coventry CV4 7EZ (United Kingdom); Kummer, M.; Knel, H. von [Laboratorium fr Festkrperphysik ETH Zrich, CH-8093 Zrich (Switzerland)

    2014-08-20T23:59:59.000Z

    The contactless surface acoustic wave technique is implemented to probe the high-frequency conductivity of a high-mobility p-Ge/GeSi quantum well structure in the regime of integer quantum Hall effect (IQHE) at temperatures 0.35.8 K and magnetic fields up to 18 T. It is shown that, in the IQHE regime at the minima of conductivity, holes are localized and ac conductivity is of hopping nature and can be described within the two-site model. The analysis of the temperature and magnetic-field-orientation dependence of the ac conductivity at odd filing factors enables us to determine the effective hole g-factor, |g{sub zz}|?4.5. It is shown that the in-plane component of the magnetic field leads to a decrease in the g-factor as well as increase in the cyclotron mass, which is explained by orbital effects in the complex valence band of germanium.

  3. The Synchronic Frame of Photospheric Magnetic Flux: The Improved Synoptic Frame

    E-Print Network [OSTI]

    Zhao, Xuepu

    of the middle panel). Because of the differential rotation of magnetic elements, the solar surface distribution from a synoptic chart do not cover the whole solar surface at any time within the period of one solar transpot models to predict better instantaneous photospheric field distribution on the portions of solar

  4. Permanent Magnet Assisted Synchronous Reluctance Machine (PMa-SynRM) Design and Performance Analysis for Fan and Pump Applications

    E-Print Network [OSTI]

    Vartanian, Robert

    2014-08-13T23:59:59.000Z

    ...................................................................................................... 14 IIB. Reference Induction Machine .......................................................................... 14 IIC. MMF Study of the NEMA Stator .................................................................... 17 IID. Simulation Results...RM. ................................................................................................................. 6 Fig 1-6: Power factor of a synchronous machine (SynRM). .............................................. 8 Fig 1-7: SynRM different rotors: (a) Conventional Salient Pole (b) Isolated Segmental, (c) Transversally Laminated, (d) Double Barrier, (e...

  5. Abstract--This paper presents an analysis by which the dynamic performances of a permanent magnet synchronous

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    synchronous motor (PMSM) motor is controlled through a hysteresis current loop and an outer speed loop, with fuzzy sliding mode speed controller show improvement in transient response of the PMSM drive over for optimal operation of a PMSM motor for wind turbine generator pumping system under its non linear

  6. E-Print Network 3.0 - ac applied magnetic Sample Search Results

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

    - Superconducting Magnet Division, Brookhaven National Laboratory Collection: Physics 97 TEST RESULTS OF HTS COILS AND AN R&D MAGNET FOR RIA* , M. Anerella, M. Harrison, J....

  7. Autonomous rigid body attitude synchronization Alain Sarlette, Rodolphe Sepulchre and Naomi Ehrich Leonard

    E-Print Network [OSTI]

    Leonard, Naomi

    Leonard Abstract-- This paper studies some extensions to the de- centralized attitude synchronization. alain.sarlette@ulg.ac.be, r.sepulchre@ulg.ac.be N.E. Leonard is with the MAE Department, Princeton

  8. Abstract --For high-speed machines applications, eddy-current losses in the interior permanent magnet of synchronous

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -current losses in magnets of PMSM, due to time harmonics of stator currents, has been developed [4] to consider of PMSM, due to space harmonics of magnetomotive force (MMF), have been presented in order t

  9. High-Performance Control of Two Three-Phase Permanent-Magnet Synchronous Machines in an Integrated Drive for Automotive Applications

    SciTech Connect (OSTI)

    Tang, Lixin [ORNL; Su, Gui-Jia [ORNL

    2008-01-01T23:59:59.000Z

    The closed-loop control of an integrated dual AC drive system is presented to control two three-phase permanent-magnet motors. A five-leg inverter is employed in the drive system; three of the inverter legs are for a main traction motor, but only two are needed for a three-phase auxiliary motor by utilizing the neutral point of the traction motor. An integrated drive with reduced component count is therefore achieved by eliminating one inverter leg and its gate drivers. A modified current control scheme based on the rotor flux orientation principle is presented. Simulation and experimental results are included to verify the independent control capability of the integrated drive.

  10. Passivity-based control of a wound-rotor synchronous Arnau D`oria-Cerezoa

    E-Print Network [OSTI]

    Batlle, Carles

    of using a WRSM in front of the permanent magnet synchronous motor (PMSM), is the ability to compensate

  11. E-Print Network 3.0 - ac magnetization measurements Sample Search...

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

    Engineering Department, Sungkyunkwan University Collection: Materials Science 79 TEST RESULTS OF HTS COILS AND AN R&D MAGNET FOR RIA* , M. Anerella, M. Harrison, J....

  12. IEEE TRANSACTIONS ON MAGNETICS, VOL. 45, NO. 12, DECEMBER 2009 5399 Modeling of the Starting Performance of Large Solid-Pole Synchronous

    E-Print Network [OSTI]

    Mi, Chunting "Chris"

    refineries, steel mills, and power plants [1]­[6]. Large solid pole motors are a special category of large virtual windings. Therefore, the two-axis theory can be used for the solid pole synchronous motor. We, starting performance, transformation coefficient, two-axis theory, virtual windings. I. INTRODUCTION LARGE

  13. Techniques for energy conservation in ac motor-driven systems. Final report

    SciTech Connect (OSTI)

    Mohan, N.

    1981-09-01T23:59:59.000Z

    Techniques for energy conservation of reducing losses in ac motor-driven systems proposed by the technical community in response to surging cost of energy are evaluated and compared. Report objectives are to provide better understanding of underlying principles and to evaluate technical and economic viability of these techniques for various applications. An important aspect considered is the impact on electric utility system in terms of harmonics, power factor of operation, and Electro-Magnetic Interference (EMI). The techniques evaluated are: NASA Power Factor Controller, a simple device for reducing power losses in lightly loaded ac motors; wanlass motor modification, a scheme of reconnecting motor windings with capacitors in series, with the intention of improving the motor efficiencies under all loading conditions; conventional variable frequency solid-state inverters which can control the speed of ac motors by producing adjustable frequency ac voltage, with a significant potential for energy conservation in pumps and air-handling systems; and other variable frequency drives and schemes including cycloconverters, slip-recovery scheme, Exxon Alternating Current Synthesizer, Venturini conversion technique, permanent magnet synchronous motors, and a device called the Phase-Liner. The impact of rapid growth in semiconductors and magnetic materials technologies is also considered.

  14. Methods, systems and apparatus for synchronous current regulation of a five-phase machine

    DOE Patents [OSTI]

    Gallegos-Lopez, Gabriel; Perisic, Milun

    2012-10-09T23:59:59.000Z

    Methods, systems and apparatus are provided for controlling operation of and regulating current provided to a five-phase machine when one or more phases has experienced a fault or has failed. In one implementation, the disclosed embodiments can be used to synchronously regulate current in a vector controlled motor drive system that includes a five-phase AC machine, a five-phase inverter module coupled to the five-phase AC machine, and a synchronous current regulator.

  15. AC 2008-1728: GEARING UP FOR THE FUTURE: A K-12/UNIVERSITY PARTNERSHIP TO CREATE AN ENGINEERING MAGNET ELEMENTARY

    E-Print Network [OSTI]

    an Engineering Magnet Elementary School This paper will describe the genesis of a new engineering themed magnet the decision to convert the school to an engineering magnet using the Engineering is Elementary curriculum programs elsewhere in the country, and the progress to date. The burgeoning interest in engineering magnet

  16. Magnetic Lossess Simulation in PM SM Drive by FE: Harmonic Superposition by Method of Locked Rotor

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Permanent magnet synchronous machine (PMSM), with its simplicity, high efficiency even at low speeds, strong

  17. A Distributed Generation Control Architecture for Islanded AC Microgrids

    E-Print Network [OSTI]

    Dominguez-Garcia, Alejandro

    1 A Distributed Generation Control Architecture for Islanded AC Microgrids Stanton T. Cady, Student Member, IEEE Abstract In this paper, we propose a distributed architecture for generation control in islanded ac microgrids with both synchronous generators and inverter-interfaced power supplies. Although

  18. Synchronous Motor Observability Study and an Improved Zero-speed Position Estimation Design

    E-Print Network [OSTI]

    Boyer, Edmond

    with the Permanent Magnet Synchronous Motor (PMSM) observability analysis for sensor- less control design. Nevertheless, there are no sufficient theoretical observability analyses for the PMSM. In the literature, only here for the surface Permanent Magnet Synchronous Motor (PMSM) to overcome position observability

  19. Advanced synchronous luminescence system

    DOE Patents [OSTI]

    Vo-Dinh, Tuan (Knoxville, TN)

    1997-01-01T23:59:59.000Z

    A method and apparatus for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition.

  20. Synchronization of Limit Sets

    E-Print Network [OSTI]

    Changpin Li; Weihua Deng

    2005-10-10T23:59:59.000Z

    In this Letter, we derive a sufficient condition of synchronizing limit sets (attractors and repellers) by using the linear feedback control technique proposed here. There examples are included. The numerical simulations and computer graphics show that our method work well.

  1. Synchronization in complex networks

    SciTech Connect (OSTI)

    Arenas, A.; Diaz-Guilera, A.; Moreno, Y.; Zhou, C.; Kurths, J.

    2007-12-12T23:59:59.000Z

    Synchronization processes in populations of locally interacting elements are in the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understand synchronization phenomena in natural systems take now advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also overview the new emergent features coming out from the interplay between the structure and the function of the underlying pattern of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.

  2. Scheduling Techniques for Synchronous and Multidimensional Synchro-nous Dataflow

    E-Print Network [OSTI]

    techniques for programs expressed as Synchronous Dataflow (SDF) and Multidimensional Synchronous dataflow-time constraints. Multidimensional Synchronous Dataflow (MDSDF) is an extension of SDF to multiple dimensions spaces, are more naturally modeled and specified than in SDF. The amount of on-chip memory available

  3. Power Supply Synchronization without Communication

    E-Print Network [OSTI]

    Moehlis, Jeff

    1 Power Supply Synchronization without Communication Leonardo A. B. T^orres, Jo~ao P. Hespanha, Jeff Moehlis Abstract--We consider the synchronization of power supplies in an isolated grid with multiple small-to-medium power sources. We show how to achieve a coordinated or synchronized behavior

  4. Advanced synchronous luminescence system

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1997-02-04T23:59:59.000Z

    A method and apparatus are disclosed for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition. 14 figs.

  5. RHIC spin flipper AC dipole controller

    SciTech Connect (OSTI)

    Oddo, P.; Bai, M.; Dawson, C.; Gassner, D.; Harvey, M.; Hayes, T.; Mernick, K.; Minty, M.; Roser, T.; Severino, F.; Smith, K.

    2011-03-28T23:59:59.000Z

    The RHIC Spin Flipper's five high-Q AC dipoles which are driven by a swept frequency waveform require precise control of phase and amplitude during the sweep. This control is achieved using FPGA based feedback controllers. Multiple feedback loops are used to and dynamically tune the magnets. The current implementation and results will be presented. Work on a new spin flipper for RHIC (Relativistic Heavy Ion Collider) incorporating multiple dynamically tuned high-Q AC-dipoles has been developed for RHIC spin-physics experiments. A spin flipper is needed to cancel systematic errors by reversing the spin direction of the two colliding beams multiple times during a store. The spin flipper system consists of four DC-dipole magnets (spin rotators) and five AC-dipole magnets. Multiple AC-dipoles are needed to localize the driven coherent betatron oscillation inside the spin flipper. Operationally the AC-dipoles form two swept frequency bumps that minimize the effect of the AC-dipole dipoles outside of the spin flipper. Both AC bumps operate at the same frequency, but are phase shifted from each other. The AC-dipoles therefore require precise control over amplitude and phase making the implementation of the AC-dipole controller the central challenge.

  6. E-Print Network 3.0 - alternative magnetic fields Sample Search...

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

    Analytical Calculation Summary: , torque, magnetic field, PM Synchronous motors 1 INTRODUCTION IRONLESS electrical machines are generally... of iron parts whose...

  7. E-Print Network 3.0 - alternating magnetic field Sample Search...

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

    Analytical Calculation Summary: , torque, magnetic field, PM Synchronous motors 1 INTRODUCTION IRONLESS electrical machines are generally... of iron parts whose...

  8. INNOVATIVE CONCEPTS FOR ON-LINE SYNCHRONOUS GENERATOR PARAMETER ESTIMATION

    E-Print Network [OSTI]

    and other routine power engineering studies. These studies are critical for the operation of the power temperature, magnetic saturation, and coupling between the generator and external systems. The method proposed and on a simplified synchronous generator model. The method is developed to be used with a Visual C++ engine

  9. Position sensor for linear synchronous motors employing halbach arrays

    DOE Patents [OSTI]

    Post, Richard Freeman

    2014-12-23T23:59:59.000Z

    A position sensor suitable for use in linear synchronous motor (LSM) drive systems employing Halbach arrays to create their magnetic fields is described. The system has several advantages over previously employed ones, especially in its simplicity and its freedom from being affected by weather conditions, accumulated dirt, or electrical interference from the LSM system itself.

  10. Synchronous operation of the BLDC motor

    E-Print Network [OSTI]

    Guzelgunler, Yilcan

    1998-01-01T23:59:59.000Z

    Back EMF 19 22 B. 3. Freewheeling Diode Conduction. . B. 4. Back EMF Integration. 27 30 C. Flux Linkage Based Method. . 33 CHAPTER Page III SENSORLESS START-UP METHODS. . 39 A. Synchronous Start-up. B. Eddy Current. . C. Diagnostic Current... Demagnetization characteristic of a magnet. 7 Flux linkage and induced voltage of phase a, 14 8 Converter configuration of BLDC motor. 19 9 Terminal voltage of phase a. . . . 19 10 Low pass filters and comparator circuit. 11 Wave forms showing how switching...

  11. Communication using Synchronized Chaotic Systems

    E-Print Network [OSTI]

    Anlage, Steven

    Communication using Synchronized Chaotic Systems Rachel Kramer Adam Cohen Bhargava Ravoori Thomas E attention for uses in secure CommunicationIntroduction Adaptive Synchronization The phenomenon sequence is transmitted over a time-varying communication channel. We examine cases with and without

  12. 436 IEEE/ASME TRANSACTIONS ON MECHATRONICS, VOL. 9, NO. 2, JUNE 2004 Torque and Velocity Ripple Elimination of AC

    E-Print Network [OSTI]

    Qiu, Li

    Elimination of AC Permanent Magnet Motor Control Systems Using the Internal Model Principle Wai-Chuen Gan and velocity ripple elimination in AC permanent magnet (PM) motor control systems. The torque ripples caused-free output response. Index Terms--AC permanent magnet motor, gain scheduled (GS) speed regulators, internal

  13. E-Print Network 3.0 - advanced permanent magnet Sample Search...

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

    Collection: Mathematics 74 Optimum Control for Interior Permanent Magnet Synchronous Motors (IPMSM) in Constant Summary: Optimum Control for Interior Permanent Magnet...

  14. Explosive Synchronization is Discontinuous

    E-Print Network [OSTI]

    Vladimir Vlasov; Yong Zou; Tiago Pereira

    2014-11-25T23:59:59.000Z

    Spontaneous explosive is an abrupt transition to collective behavior taking place in heterogeneous networks when the frequencies of the nodes are positively correlated to the node degree. This explosive transition was conjectured to be discontinuous. Indeed, numerical investigations reveal a hysteresis behavior associated with the transition. Here, we analyze explosive synchronization in star graphs. We show that in the thermodynamic limit the transition to (and out) collective behavior is indeed discontinuous. The discontinuous nature of the transition is related to the nonlinear behavior of the order parameter, which in the thermodynamic limit exhibits multiple fixed points. Moreover, we unravel the hysteresis behavior in terms of the graph parameters. Our numerical results show that finite size graphs are well described by our predictions.

  15. active magnetic regenerative: Topics by E-print Network

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

    by this sensor synchronized with the electric activity of the electrocardiogram (ECG). The shape of the magnetic wave was largely altered by shifting the sensor position...

  16. Permanent-magnet-less machine having an enclosed air gap

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN)

    2012-02-07T23:59:59.000Z

    A permanent magnet-less, brushless synchronous system includes a stator that generates a magnetic rotating field when sourced by an alternating current. An uncluttered rotor disposed within the magnetic rotating field is spaced apart from the stator to form an air gap relative to an axis of rotation. A stationary excitation core spaced apart from the uncluttered rotor by an axial air gap and a radial air gap substantially encloses the stationary excitation core. Some permanent magnet-less, brushless synchronous systems include stator core gaps to reduce axial flux flow. Some permanent magnet-less, brushless synchronous systems include an uncluttered rotor coupled to outer laminations. The quadrature-axis inductance may be increased in some synchronous systems. Some synchronous systems convert energy such as mechanical energy into electrical energy (e.g., a generator); other synchronous systems may convert any form of energy into mechanical energy (e.g., a motor).

  17. Permanent-magnet-less machine having an enclosed air gap

    DOE Patents [OSTI]

    Hsu, John S.

    2013-03-05T23:59:59.000Z

    A permanent magnet-less, brushless synchronous system includes a stator that generates a magnetic rotating field when sourced by an alternating current. An uncluttered rotor disposed within the magnetic rotating field is spaced apart from the stator to form an air gap relative to an axis of rotation. A stationary excitation core spaced apart from the uncluttered rotor by an axial air gap and a radial air gap substantially encloses the stationary excitation core. Some permanent magnet-less, brushless synchronous systems include stator core gaps to reduce axial flux flow. Some permanent magnet-less, brushless synchronous systems include an uncluttered rotor coupled to outer laminations. The quadrature-axis inductance may be increased in some synchronous systems. Some synchronous systems convert energy such as mechanical energy into electrical energy (e.g., a generator); other synchronous systems may convert any form of energy into mechanical energy (e.g., a motor).

  18. Synchronization in an Optomechanical Cavity

    E-Print Network [OSTI]

    Keren Shlomi; D. Yuvaraj; Ilya Baskin; Oren Suchoi; Roni Winik; Eyal Buks

    2014-10-01T23:59:59.000Z

    We study self-excited oscillations (SEO) in an on-fiber optomechanical cavity. Synchronization is observed when the optical power that is injected into the cavity is periodically modulated. A theoretical analysis based on the Fokker-Planck equation evaluates the expected phase space distribution (PSD) of the self-oscillating mechanical resonator. A tomography technique is employed for extracting PSD from the measured reflected optical power. Time-resolved state tomography measurements are performed to study phase diffusion and phase locking of the SEO. The detuning region inside which synchronization occurs is experimentally determined and the results are compared with the theoretical prediction.

  19. On the role of flexoeffect in synchronization of electroconvective roll oscillations in nematics

    SciTech Connect (OSTI)

    Batyrshin, E. S., E-mail: batyrshin@anrb.ru; Krekhov, A. P.; Scaldin, O. A.; Delev, V. A. [Russian Academy of Sciences, Institute of Molecular and Crystal Physics, Ufa Research Center (Russian Federation)

    2012-06-15T23:59:59.000Z

    We describe the dynamics of zigzag oscillations in a system of convective rolls in a nematic liquid crystal above the electroconvection threshold under the action of an ac voltage with a biased position of the mean value. It is found that an increase in the contribution from the constant component leads to a substantial increase in the spatiotemporal ordering of zigzag rolls and their synchronization with the homogeneous twist mode. The results confirm the flexoelectric mechanism of locking.

  20. Fermi Timing and Synchronization System

    SciTech Connect (OSTI)

    Wilcox, R.; Staples, J.; Doolittle, L.; Byrd, J.; Ratti, A.; Kaertner, F.X.; Kim, J.; Chen, J.; Ilday, F.O.; Ludwig, F.; Winter, A.; Ferianis, M.; Danailov, M.; D'Auria, G.

    2006-07-19T23:59:59.000Z

    The Fermi FEL will depend critically on precise timing of its RF, laser and diagnostic subsystems. The timing subsystem to coordinate these functions will need to reliably maintain sub-100fs synchronicity between distant points up to 300m apart in the Fermi facility. The technology to do this is not commercially available, and has not been experimentally demonstrated in a working facility. Therefore, new technology must be developed to meet these needs. Two approaches have been researched by different groups working with the Fermi staff. At MIT, a pulse transmission scheme has been developed for synchronization of RF and laser devices. And at LBL, a CW transmission scheme has been developed for RF and laser synchronization. These respective schemes have advantages and disadvantages that will become better understood in coming years. This document presents the work done by both teams, and suggests a possible system design which integrates them both. The integrated system design provides an example of how choices can be made between the different approaches without significantly changing the basic infrastructure of the system. Overall system issues common to any synchronization scheme are also discussed.

  1. Hub Synchronization in Scale-Free Networks

    E-Print Network [OSTI]

    Tiago Pereira

    2010-10-07T23:59:59.000Z

    Heterogeneity in the degree distribution is known to suppress global synchronization in complex networks of symmetrically coupled oscillators. Scale-free networks display a great deal of heterogeneity, containing a few nodes, termed hubs, that are highly connected, while most nodes receive only a few connections. Here, we show that a group of synchronized nodes may appear in scale-free networks: hubs undergo a transition to synchronization while the other nodes remain unsynchronized. This general phenomenon can occur even in the absence of global synchronization. Our results suggest that scale-free networks may have evolved to complement various levels of synchronization.

  2. A Multi-Level Grid Interactive Bi-directional AC/DC-DC/AC Converter and a Hybrid Battery/Ultra-capacitor Energy Storage System with Integrated Magnetics for Plug-in Hybrid Electric Vehicles

    SciTech Connect (OSTI)

    Onar, Omer C [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    This study presents a bi-directional multi-level power electronic interface for the grid interactions of plug-in hybrid electric vehicles (PHEVs) as well as a novel bi-directional power electronic converter for the combined operation of battery/ultracapacitor hybrid energy storage systems (ESS). The grid interface converter enables beneficial vehicle-to-grid (V2G) interactions in a high power quality and grid friendly manner; i.e, the grid interface converter ensures that all power delivered to/from grid has unity power factor and almost zero current harmonics. The power electronic converter that provides the combined operation of battery/ultra-capacitor system reduces the size and cost of the conventional ESS hybridization topologies while reducing the stress on the battery, prolonging the battery lifetime, and increasing the overall vehicle performance and efficiency. The combination of hybrid ESS is provided through an integrated magnetic structure that reduces the size and cost of the inductors of the ESS converters. Simulation and experimental results are included as prove of the concept presenting the different operation modes of the proposed converters.

  3. Digital-data receiver synchronization

    DOE Patents [OSTI]

    Smith, Stephen F.; Turner, Gary W.

    2005-08-02T23:59:59.000Z

    Digital-data receiver synchronization is provided with composite phase-frequency detectors, mutually cross-connected comparison feedback or both to provide robust reception of digital data signals. A single master clock can be used to provide frequency signals. Advantages can include fast lock-up time in moderately to severely noisy conditions, greater tolerance to noise and jitter when locked, and improved tolerance to clock asymmetries.

  4. Synchronization Difficulties Between Traditional Faculty and

    E-Print Network [OSTI]

    Henderson, Charles

    at the AAPT Summer Meeting, August 9, 2005, Salt Lake City, UT 3 Abstract To identify barriersSynchronization Difficulties Between Traditional Faculty and Education Researchers Charles

  5. Synchronous Machine Faults Detection and Diagnosis for Electro-mechanical Actuators

    E-Print Network [OSTI]

    Boyer, Edmond

    Detection and Isolation system for permanent magnet synchronous machine (PMSM). Two main faults occurring for the machine control. To illustrate the method an application is made on an innovative 12-slots 10-poles PMSM that becomes more and more popular in aeronautics, and on a 9-slots 8-poles PMSM used in critical application

  6. Spectral Clustering of Synchronous Spike Trains 1 Spectral Clustering of Synchronous

    E-Print Network [OSTI]

    Paiva, António R. C.

    Spectral Clustering of Synchronous Spike Trains 1 Spectral Clustering of Synchronous Spike Trains, University of Florida #12;Spectral Clustering of Synchronous Spike Trains 2 Outline Introduction Distance between two spike trains Clustering algorithm Results António Paiva, Sudhir Rao, Il Park and José Príncipe

  7. Title of dissertation: SYNCHRONIZATION OF CHAOTIC OPTOELECTRONIC OSCILLATORS

    E-Print Network [OSTI]

    Anlage, Steven

    ABSTRACT Title of dissertation: SYNCHRONIZATION OF CHAOTIC OPTOELECTRONIC OSCILLATORS: ADAPTIVE channels. Here, using a fiber-optic network of chaotic optoelectronic oscillators, we experimentally on synchronization. Through measurements of the convergence rate to synchronization in networks of optoelectronic

  8. Control of Two Permanent Magnet Machines Using a Five-Leg Inverter for Automotive Applications

    SciTech Connect (OSTI)

    Su, Gui-Jia [ORNL; Tang, Lixin [ORNL; Huang, Xianghui [GE Global Research

    2006-01-01T23:59:59.000Z

    This paper presents digital control schemes for control of two permanent magnet (PM) machines in an integrated traction and air-conditioning compressor drive system for automotive applications. The integrated drive system employs a five-leg inverter to power a three-phase traction PM motor and a two-phase compressor PM motor by tying the common terminal of the two-phase motor to the neutral point of the three-phase motor. Compared to a three-phase or a standalone two-phase inverter, it eliminates one phase leg and shares the control electronics between the two drives, thus significantly reducing the component count of the compressor drive. To demonstrate that the speed and torque of the two PM motors can be controlled independently, a control strategy was implemented in a digital signal processor, which includes a rotor flux field orientation based control (RFOC) for the three-phase motor, a similar RFOC and a position sensorless control in the brushless dc (BLDC) mode for the two-phase motor. Control implementation issues unique to a two-phase PM motor are also discussed. Test results with the three-phase motor running in the ac synchronous (ACS) mode while the two-phase motor either in the ACS or the BLDC mode are included to verify the independent speed and torque control capability of the integrated drive.

  9. Biologically inspired mutual synchronization of manufacturing machines

    E-Print Network [OSTI]

    Armbruster, Dieter

    Biologically inspired mutual synchronization of manufacturing machines Erjen Lefeber,a,1 , Herman machine is developed. This control system is based on a synchronization mechanism of enzymes replacing of a single turnover cycle. In manufacturing, batch machines serve several jobs simultaneously, e.g., heat

  10. Design of coupling for synchronization in time-delayed systems

    E-Print Network [OSTI]

    Dibakar Ghosh; Ioan Grosu; Syamal Kumar Dana

    2012-07-03T23:59:59.000Z

    We report a design of delay coupling for targeting desired synchronization in delay dynamical systems. We target synchronization, antisynchronization, lag-, antilag- synchronization, amplitude death (or oscillation death) and generalized synchronization in mismatched oscillators. A scaling of the size of an attractor is made possible in different synchronization regimes. We realize a type of mixed synchronization where synchronization, antisynchronization coexist in different pairs of state variables of the coupled system. We establish the stability condition of synchronization using the Krasovskii-Lyapunov function theory and the Hurwitz matrix criterion. We present numerical examples using the Mackey-Glass system and a delay R\\"{o}ssler system.

  11. Clustering versus non-clustering phase synchronizations

    SciTech Connect (OSTI)

    Liu, Shuai [Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China) [Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhan, Meng, E-mail: zhanmeng@wipm.ac.cn [Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)] [Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)

    2014-03-15T23:59:59.000Z

    Clustering phase synchronization (CPS) is a common scenario to the global phase synchronization of coupled dynamical systems. In this work, a novel scenario, the non-clustering phase synchronization (NPS), is reported. It is found that coupled systems do not transit to the global synchronization until a certain sufficiently large coupling is attained, and there is no clustering prior to the global synchronization. To reveal the relationship between CPS and NPS, we further analyze the noise effect on coupled phase oscillators and find that the coupled oscillator system can change from CPS to NPS with the increase of noise intensity or system disorder. These findings are expected to shed light on the mechanism of various intriguing self-organized behaviors in coupled systems.

  12. Spiking Optical Patterns and Synchronization

    E-Print Network [OSTI]

    Rosenbluh, Michael; Cohen, Elad; Khaykovich, Lev; Kinzel, Wolfgang; Kopelowitz, Evi; Yoskovits, Pinhas; Kanter, Ido

    2007-01-01T23:59:59.000Z

    We analyze the time resolved spike statistics of a solitary and two mutually interacting chaotic semiconductor lasers whose chaos is characterized by apparently random, short intensity spikes. Repulsion between two successive spikes is observed, resulting in a refractory period which is largest at laser threshold. For time intervals between spikes greater than the refractory period, the distribution of the intervals follows a Poisson distribution. The spiking pattern is highly periodic over time windows corresponding to the optical length of the external cavity, with a slow change of the spiking pattern as time increases. When zero-lag synchronization between the two lasers is established, the statistics of the nearly perfectly matched spikes are not altered. The similarity of these features to those found in complex interacting neural networks, suggests the use of laser systems as simpler physical models for neural networks.

  13. Synchronized sampling improves fault location

    SciTech Connect (OSTI)

    Kezunovic, M. [Texas A and M Univ., College Station, TX (United States)] [Texas A and M Univ., College Station, TX (United States); Perunicic, B. [Lamar Univ., Beaumont, TX (United States)] [Lamar Univ., Beaumont, TX (United States)

    1995-04-01T23:59:59.000Z

    Transmission line faults must be located accurately to allow maintenance crews to arrive at the scene and repair the faulted section as soon as possible. Rugged terrain and geographical layout cause some sections of power transmission lines to be difficult to reach. In the past, a variety of fault location algorithms were introduced as either an add-on feature in protective relays or stand-alone implementation in fault locators. In both cases, the measurements of current and voltages were taken at one terminal of a transmission line only. Under such conditions, it may become difficult to determine the fault location accurately, since data from other transmission line ends are required for more precise computations. In the absence of data from the other end, existing algorithms have accuracy problems under several circumstances, such as varying switching and loading conditions, fault infeed from the other end, and random value of fault resistance. Most of the one-end algorithms were based on estimation of voltage and current phasors. The need to estimate phasors introduces additional difficulty in high-speed tripping situations where the algorithms may not be fast enough in determining fault location accurately before the current signals disappear due to the relay operation and breaker opening. This article introduces a unique concept of high-speed fault location that can be implemented either as a simple add-on to the digital fault recorders (DFRs) or as a stand-alone new relaying function. This advanced concept is based on the use of voltage and current samples that are synchronously taken at both ends of a transmission line. This sampling technique can be made readily available in some new DFR designs incorporating receivers for accurate sampling clock synchronization using the satellite Global Positioning System (GPS).

  14. Mutual synchronization of two stacks of intrinsic Josephson junctions in cuprate superconductors

    SciTech Connect (OSTI)

    Lin, Shi-Zeng [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-05-07T23:59:59.000Z

    Certain high-T{sub c} cuprate superconductors, which naturally realize a stack of Josephson junctions, thus can be used to generate electromagnetic waves in the terahertz region. A plate-like single crystal with 10{sup 4} junctions without cavity resonance was proposed to achieve strong radiation. For this purpose, it is required to synchronize the Josephson plasma oscillation in all junctions. In this work, we propose to use two stacks of junctions shunted in parallel to achieve synchronization. The two stacks are mutually synchronized in the whole IV curve, and there is a phase shift between the plasma oscillation in the two stacks. The phase shift is nonzero when the number of junctions in different stacks is the same, while it can be arbitrary when the number of junctions is different. This phase shift can be tuned continuously by applying a magnetic field when all the junctions are connected by superconducting wires.

  15. Real-Time Capable Methods to Determine the Magnet Temperature of Permanent Magnet

    E-Print Network [OSTI]

    Paderborn, Universität

    }@lea.upb.de Abstract--The permanent magnet synchronous motor (PMSM) is widely used in highly utilised automotive-based magnet temperature determination methods in PMSM. In this context, the existing publications can field. Keywords--PMSM, permanent magnet temperature, model- based real-time determination, motor control

  16. On chip synchronization for optical OPPM

    E-Print Network [OSTI]

    Hayek, Khalil F.

    2012-06-07T23:59:59.000Z

    the autocorrclation and spectrum of the output of a photodiode photodetector for Q-ary VVM and showed the necessity for nonlinear preprocessing to obtain a synchronizable signal which can then be locked on to by a phase-locked loop; in addition, they studied the ef...Fect of imperfect synchronization on system performance. Slot synchronization for avalanche photodiode (APD) receivers was considered by Davidson and Sun [7]. Synchronization was achieved by using a transition detector followed by a pulse shaper to provide input...

  17. Quantum Clock Synchronization with a Single Qudit

    E-Print Network [OSTI]

    Armin Tavakoli; Adn Cabello; Marek ?ukowski; Mohamed Bourennane

    2015-01-23T23:59:59.000Z

    Clock synchronization for nonfaulty processes in multiprocess networks is indispensable for a variety of technologies. A reliable system must be able to resynchronize the nonfaulty processes upon some components failing causing the distribution of incorrect or conflicting information in the network. The task of synchronizing such networks is related to detectable Byzantine agreement (DBA), which can classically be solved using recursive algorithms if and only if less than one-third of the processes are faulty. Here we introduce a nonrecursive quantum algorithm that solves the DBA and achieves clock synchronization in the presence of arbitrary many faulty processes by using only a single quantum system.

  18. Synchronization System for Next Generation Light Sources

    SciTech Connect (OSTI)

    Zavriyev, Anton

    2014-03-27T23:59:59.000Z

    An alternative synchronization technique one that would allow explicit control of the pulse train including its repetition rate and delay is clearly desired. We propose such a scheme. Our method is based on optical interferometry and permits synchronization of the pulse trains generated by two independent mode-locked lasers. As the next generation x-ray sources will be driven by a clock signal derived from a mode-locked optical source, our technique will provide a way to synchronize x-ray probe with the optical pump pulses.

  19. Synchronization of coupled large-scale Boolean networks

    SciTech Connect (OSTI)

    Li, Fangfei, E-mail: li-fangfei@163.com [Department of Mathematics, East China University of Science and Technology, No. 130, Meilong Road, Shanghai, Shanghai 200237 (China)] [Department of Mathematics, East China University of Science and Technology, No. 130, Meilong Road, Shanghai, Shanghai 200237 (China)

    2014-03-15T23:59:59.000Z

    This paper investigates the complete synchronization and partial synchronization of two large-scale Boolean networks. First, the aggregation algorithm towards large-scale Boolean network is reviewed. Second, the aggregation algorithm is applied to study the complete synchronization and partial synchronization of large-scale Boolean networks. Finally, an illustrative example is presented to show the efficiency of the proposed results.

  20. Scheduling and synchronization for multicore concurrency platforms

    E-Print Network [OSTI]

    Agrawal, Kunal

    2009-01-01T23:59:59.000Z

    Developing correct and efficient parallel programs is difficult since programmers often have to manage low-level details like scheduling and synchronization explicitly. Recently, however, many hardware vendors have been ...

  1. Commande cooprative des systmes monoconvertisseurs multimachines synchrones.

    E-Print Network [OSTI]

    Bidart, Damien

    2011-01-01T23:59:59.000Z

    ??Afin de rendre les machines synchrones aimants permanents plus attractives pour l'aronautique (actionneurs de commande de vol, systmes de freinage, train d'atterrissage ...), il (more)

  2. Synchronization of Mechanical Oscillators: An Experimental Study

    E-Print Network [OSTI]

    Daneshvar, Roozbeh

    2011-02-22T23:59:59.000Z

    SYNCHRONIZATION OF MECHANICAL OSCILLATORS: AN EXPERIMENTAL STUDY A Thesis by ROOZBEH DANESHVAR Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE December... 2010 Major Subject: Electrical Engineering SYNCHRONIZATION OF MECHANICAL OSCILLATORS: AN EXPERIMENTAL STUDY A Thesis by ROOZBEH DANESHVAR Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements...

  3. Global Analysis of Synchronization in Coupled Maps

    E-Print Network [OSTI]

    Juergen Jost; Kiran M. Kolwankar

    2005-12-02T23:59:59.000Z

    We introduce a new method for determining the global stability of synchronization in systems of coupled identical maps. The method is based on the study of invariant measures. Besides the simplest non-trivial example, namely two symmetrically coupled tent maps, we also treat the case of two asymmetrically coupled tent maps as well as a globally coupled network. Our main result is the identification of the precise value of the coupling parameter where the synchronizing and desynchronizing transitions take place.

  4. Microfabricated AC impedance sensor

    DOE Patents [OSTI]

    Krulevitch, Peter (Pleasanton, CA); Ackler, Harold D. (Sunnyvale, CA); Becker, Frederick (Houston, TX); Boser, Bernhard E. (Berkeley, CA); Eldredge, Adam B. (Austin, TX); Fuller, Christopher K. (Livermore, CA); Gascoyne, Peter R. C. (Bellaire, TX); Hamilton, Julie K. (Tracy, CA); Swierkowski, Stefan P. (Livermore, CA); Wang, Xiao-Bo (San Diego, CA)

    2002-01-01T23:59:59.000Z

    A microfabricated instrument for detecting and identifying cells and other particles based on alternating current (AC) impedance measurements. The microfabricated AC impedance sensor includes two critical elements: 1) a microfluidic chip, preferably of glass substrates, having at least one microchannel therein and with electrodes patterned on both substrates, and 2) electrical circuits that connect to the electrodes on the microfluidic chip and detect signals associated with particles traveling down the microchannels. These circuits enable multiple AC impedance measurements of individual particles at high throughput rates with sufficient resolution to identify different particle and cell types as appropriate for environmental detection and clinical diagnostic applications.

  5. Superconducting magnets for muon capture and phase rotation

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    LBNL-43998 SC-MAG-683 SUPERCONDUCTING MAGNETS FOR MUONDE-AC03-76SF00098. Green SUPERCONDUCTING MAGNETS FOR MUONet ai, "The Use of Superconducting Solenoids in a Muon

  6. A robust coordinated control scheme for HVDC transmission with parallel AC systems

    SciTech Connect (OSTI)

    To, K.W.V.; David, A.K. (Hong Kong Polytechnic (Hong Kong). Dept. of Electrical Engineering); Hammad, A.E. (N.E. Swiss Power Co., Baden (Switzerland))

    1994-07-01T23:59:59.000Z

    This paper introduces a practical control philosophy for HVDC transmission in parallel operation to an AC system with particular emphasis on coordination of both transient and dynamic stability. Systematic development of the control scheme on the basis of on-line identification, optimal control and rule-based bang-optimal coordination principles is presented. Verification tests of the scheme on a physical HVDC/AC system simulator show that the simple control computer algorithm is practical and robust. The controller can successfully distinguish between different system fault severities and adapts its output signals to provide maximum synchronizing torque and ensure optimal damping of power oscillations.

  7. Generalized synchronization of chaos in autonomous systems

    E-Print Network [OSTI]

    O. Alvarez-Llamoza; M. G. Cosenza

    2008-10-13T23:59:59.000Z

    We extend the concept of generalized synchronization of chaos, a phenomenon that occurs in driven dynamical systems, to the context of autonomous spatiotemporal systems. It means a situation where the chaotic state variables in an autonomous system can be synchronized to each other but not to a coupling function defined from them. The form of the coupling function is not crucial; it may not depend on all the state variables nor it needs to be active for all times for achieving generalized synchronization. The procedure is based on the analogy between a response map subject to an external drive acting with a probability p and an autonomous system of coupled maps where a global interaction between the maps takes place with this same probability. It is shown that, under some circumstances, the conditions for stability of generalized synchronized states are equivalent in both types of systems. Our results reveal the existence of similar minimal conditions for the emergence of generalized synchronization of chaos in driven and in autonomous spatiotemporal systems.

  8. Time delayed laser networks: phase versus chaos synchronization

    E-Print Network [OSTI]

    Reidler, I; Aviad, Y; Guberman, S; Friesem, A A; Rosenbluh, M; Davidson, N; Kanter, I

    2013-01-01T23:59:59.000Z

    The synchronization of chaotic lasers and the optical phase synchronization of light originating in multiple coupled lasers have both been extensively studied, however, the interplay between these two phenomena, especially at the network level is unexplored. Here we experimentally compare chaos synchronization of laser networks with heterogeneous coupling delay times to phase synchronization of similar networks. While chaotic lasers exhibit deterioration in synchronization as the network time delay heterogeneity increases, phase synchronization is found to be independent of heterogeneity. The experimental results are found to be in agreement with numerical simulations for semiconductor lasers.

  9. Time delayed laser networks: phase versus chaos synchronization

    E-Print Network [OSTI]

    I. Reidler; M. Nixon; Y. Aviad; S. Guberman; A. A. Friesem; M. Rosenbluh; N. Davidson; I. Kanter

    2013-04-03T23:59:59.000Z

    The synchronization of chaotic lasers and the optical phase synchronization of light originating in multiple coupled lasers have both been extensively studied, however, the interplay between these two phenomena, especially at the network level is unexplored. Here we experimentally compare chaos synchronization of laser networks with heterogeneous coupling delay times to phase synchronization of similar networks. While chaotic lasers exhibit deterioration in synchronization as the network time delay heterogeneity increases, phase synchronization is found to be independent of heterogeneity. The experimental results are found to be in agreement with numerical simulations for semiconductor lasers.

  10. Synchronous Droplet Microfluidics: One "Clock" to rule them all

    E-Print Network [OSTI]

    Katsikis, Georgios

    2013-01-01T23:59:59.000Z

    Controlling fluid droplets efficiently in the microscale is of great interest both from a basic science and a technology perspective. We have designed and developed a general-purpose, highly scalable microfluidic control strategy through a single global clock signal that enables synchronous control of arbitrary number of droplets in a planar geometry. A rotating precessive magnetic field provides a global clock signal, enabling simultaneous control of droplet position, velocity and trajectories. Here, in this fluid dynamics video, we explain the main physics of this new microfluidic concept. Video data from droplets moving in sync in different fluidic circuits are included. The experimental setup is described and video data is analyzed to provide a detailed view of the time-dynamics of propagating droplets. Finally, we explore the operational limits of this concept, scaling and phase diagram with physical regime diagram.

  11. Soft-Switching High-Frequency AC-Link Universal Power Converters with Galvanic Isolation

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07T23:59:59.000Z

    ) direct drive using wound-field synchronous generator [10]. ...................................................................................................... 6 Figure 6 Dc-dc buck-boost converter: (a) configuration, (b) energizing mode (mode 1), (c...) de-energizing mode (mode 2), (d) voltage and current waveforms ........ 12 Figure 7 An alternative representation of the dc-dc buck-boost converter ...................... 13 Figure 8 Dc-dc ac-link buck-boost converter: configuration, behavior...

  12. Driven synchronization in random networks of oscillators

    E-Print Network [OSTI]

    Hindes, Jason

    2015-01-01T23:59:59.000Z

    Synchronization is a universal phenomenon found in many non-equilibrium systems. Much recent interest in this area has overlapped with the study of complex networks, where a major focus is determining how a system's connectivity patterns affect the types of behavior that it can produce. Thus far, modeling efforts have focused on the tendency of networks of oscillators to mutually synchronize themselves, with less emphasis on the effects of external driving. In this work we discuss the interplay between mutual and driven synchronization in networks of phase oscillators of the Kuramoto type, and resolve how the structure and emergence of such states depends on the underlying network topology for simple random networks with a given degree distribution. We provide a partial bifurcation analysis, centering on the appearance of a Takens-Bogdanov-Cusp singularity, which broadly separates homogeneous and heterogeneous network behavior in a weak coupling limit, and from which the number, stability and appearance of dr...

  13. Selection Tests of MnZn and NiZn Ferrites for Mu2e 300 kHz and 5.1 MHz AC Dipoles

    SciTech Connect (OSTI)

    Bourkland, K.; Elementi, L.; Feher, S.; Harding, D.J.; Kashikhin, V.S.; Makarov, A.; Pfeffer, H.; Velev, G.V.; /Fermilab; Mulushev, E.; /Institute of Automatics and Electrometry; Iedmeska, I.; /Moscow, MIPT; Venturini, M.; /Pisa U.

    2011-09-09T23:59:59.000Z

    Mu2e, a charged lepton flavor violation (CLFV) experiment is planned to start at Fermilab late in this decade. The proposed experiment will search for neutrinoless muon to electron conversions with unprecedented sensitivity, better than 6 x 10{sup -17 }at 90% CL. To achieve this sensitivity the incoming proton beam must be highly suppressed during the window for detecting the muon decays. The current proposal for beam extinction is based on a collimator design with two dipoles running at {approx}300 kHz and 5.1 MHz and synchronized to the proton bunch spacing. The appropriate choice of ferrite material for the magnet yoke is a critical step in the overall design of the dipoles and their reliable operation at such high frequencies over the life of the experiment. This choice, based on a series of the thermal and magnetic measurements of the ferrite samples, is discussed in the paper. Additionally, the first results from the testing at 300 kHz of a prototype AC dipole are presented.

  14. CD54AC04, CD74AC04 HEX INVERTERS

    E-Print Network [OSTI]

    Kretchmar, R. Matthew

    °C to 125°C SOIC M Tube CD74AC04M AC04M­55°C to 125°C SOIC ­ M Tape and reel CD74AC04M96 AC04M CDIP-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed. 2. The package thermal impedance

  15. Behavioral/Systems/Cognitive Synchronous, Focally Modulated -Band Oscillations

    E-Print Network [OSTI]

    Graybiel, Ann M.

    , primarily synchronous -band voltage oscillations occur in the sensorimotor and frontal cortex of humansBehavioral/Systems/Cognitive Synchronous, Focally Modulated -Band Oscillations Characterize Local oscillations in the -frequency band ( 1530Hz

  16. New approach to the fault location problem using synchronized sampling

    E-Print Network [OSTI]

    Mrkic, Jasna

    2012-06-07T23:59:59.000Z

    This thesis presents a new approach to solving the problem of fault location on a transmission line using synchronized data from both ends of the line. The synchronized phase voltage and current samples taken during the fault transient are used...

  17. Blind Block Synchronization Algorithms in Cyclic Prefix Systems

    E-Print Network [OSTI]

    Vaidyanathan, P. P.

    Blind Block Synchronization Algorithms in Cyclic Prefix Systems Borching Su Department to solving the problem blindly, that is, where training symbols are not available. Blind symbol synchronization problem is especially important in many blind channel estimation algorithms in the literature

  18. Magnetic core studies at LBNL and LLNL

    E-Print Network [OSTI]

    Molvik, A.W.

    2008-01-01T23:59:59.000Z

    LLNL) and DE-AC03-76SF00098 (LBNL). References Wayne Meier,Magnetic Core Studies at LBNL and LLNL A. W. Molvik a,* , A.Livermore, CA 94550, USA LBNL, Berkeley, CA 94720, USA c

  19. Pattern formation of dipolar colloids in rotating fields: Layering and synchronization

    E-Print Network [OSTI]

    Sebastian Jaeger; Sabine H. L. Klapp

    2011-03-04T23:59:59.000Z

    We report Brownian dynamics (BD) simulation and theoretical results for a system of spherical colloidal particles with permanent dipole moments in a rotating magnetic field. Performing simulations at a fixed packing fraction and dipole coupling parameter, we construct a full non-equilibrium phase diagram as function of the driving frequency ($\\omega_0$) and field strength ($B_0$). This diagram contains both synchronized states, where the individual particles follow the field with (on average) constant phase difference, and asynchronous states. The synchronization is accompanied by layer formation, i.e. by spatial symmetry-breaking, similar to systems of induced dipoles in rotating fields. In the permanent-dipole case, however, too large $\\omega_0$ yield a breakdown of layering, supplemented by complex changes of the single-particle rotational dynamics from synchronous to asynchronous behavior. We show that the limit frequencies $\\omega_c$ can be well described as a bifurcation in the nonlinear equation of motion of a single particle rotating in a viscous medium. Finally, we present a simple density functional theory, which describes the emergence of layers in perfectly synchronized states as an equilibrium phase transition.

  20. The Simulation of Synchronous Reactive Systems In Ptolemy II

    E-Print Network [OSTI]

    The Simulation of Synchronous Reactive Systems In Ptolemy II by Paul Whitaker Submitted to the Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, in partial;_____________________________________________________________________ Simulation of Synchronous Reactive Systems in Ptolemy II ii Abstract The Synchronous Reactive (SR) domain

  1. Scheduling Techniques for Synchronous and Multidimensional Synchro nous Dataflow

    E-Print Network [OSTI]

    techniques for programs expressed as Synchronous Dataflow (SDF) and Multidimensional Synchronous dataflow­time constraints. Multidimensional Synchronous Dataflow (MDSDF) is an extension of SDF to multiple dimensions spaces, are more naturally modeled and specified than in SDF. The amount of on­chip memory available

  2. Simulation of Synchronous Machines This chapter covers

    E-Print Network [OSTI]

    McCalley, James D.

    by the following. · We are about to perform a time domain simulation of a multi machine system where each machine1 Simulation of Synchronous Machines This chapter covers: (A) Sections 5.25.7: Determination of initial conditions (B) Section 5.8: Determination of machine parameters from manufacturers' data

  3. Clock synchronization for mobile ad hoc networks

    E-Print Network [OSTI]

    Chandra, Rajan

    2013-02-22T23:59:59.000Z

    Time Protocol) used in wired networks (e.g. Internet) to Mobile Ad Hoc Networks (MANets). It may also be achieved by developing other algorithms that achieve clock synchronization and may be suitable for MANets. Using the Network Time Protocol (NTP...

  4. Driven synchronization in random networks of oscillators

    E-Print Network [OSTI]

    Jason Hindes; Christopher R. Myers

    2015-02-28T23:59:59.000Z

    Synchronization is a universal phenomenon found in many non-equilibrium systems. Much recent interest in this area has overlapped with the study of complex networks, where a major focus is determining how a system's connectivity patterns affect the types of behavior that it can produce. Thus far, modeling efforts have focused on the tendency of networks of oscillators to mutually synchronize themselves, with less emphasis on the effects of external driving. In this work we discuss the interplay between mutual and driven synchronization in networks of phase oscillators of the Kuramoto type, and resolve how the structure and emergence of such states depends on the underlying network topology for simple random networks with a given degree distribution. We provide a partial bifurcation analysis, centering on the appearance of a Takens-Bogdanov-Cusp singularity, which broadly separates homogeneous and heterogeneous network behavior in a weak coupling limit, and from which the number, stability and appearance of driven and mutually synchronized states can be determined, as a function of a few parameters. We find transitions such as Saddle-Node-Infinite-Periods, Limit-Point-of-Cycles, and Hopf bifurcations (both branches), as well as multiple bistability regions and dynamics that differ for the network types. This description is connected to the underlying dynamics of oscillator clusters for important states and transitions. Our results can provide a basis for studying the problem of frequency controlling disordered oscillator networks.

  5. Synchronized phasor measurements and the ``SYNCHROPHASOR`` standard

    SciTech Connect (OSTI)

    Phadke, A.G. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

    1996-10-01T23:59:59.000Z

    Synchronized phasor measurements have become a practical proposition only during the last few years. As such, their potential for use in power system applications has not yet been fully realized. Anticipating that this technology is about to take off, the Power System Relaying Committee of the IEEE has developed a standard which defines the interface between the Global Positioning System (GPS) and the Phasor Measuring Unit (PMU), and for the communication link between the PMUs and a remote site. The standard (SYNCHROPHASOR) will be published during 1996, and should facilitate the widespread application of this emerging technology. The standard defines the following features of the PMU: format of the message which contains the phasor data, time-tag specification, data frame composition, and a check sum. The standard also includes a specification for the synchronizing pulses which may be produced by a GPS receiver, or by some other synchronizing source. Synchronized phasor measurement units may well be the universal power system transducer of the future. It will serve the needs of all monitoring and control functions in power system control centers, and in many of the back-up relaying functions.

  6. Networks, smart grids: new model for synchronization

    E-Print Network [OSTI]

    - 1 - Networks, smart grids: new model for synchronization May 21, 2013 Networks of individual scenarios and in smart grid applications. "Smart grid" refers to technology to modernize utility electricity in a volatile smart grid scenario that included fluctuating loads with random power demand, renewable energy

  7. Generation and Synchronous TreeAdjoining Grammars

    E-Print Network [OSTI]

    Shieber, Stuart

    Generation and Synchronous Tree­Adjoining Grammars Stuart M. Shieber Yves Schabes Aiken Computation) have been proposed as a formal­ ism for generation based on the intuition that the extended domain serving as an aid to generation from semantic representations. We demonstrate that this intuition can

  8. E-Print Network 3.0 - annual magnet technology Sample Search...

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

    State University Collection: Chemistry 11 LITERATURE SURVEY OF PERMANENT MAGNET AC MOTORS AND P. PILIAY, MEMBER, IEEE, AND P. EREERE Summary: M.A. Rahman, "High efficiency...

  9. E-Print Network 3.0 - assessing dynamic magnetic Sample Search...

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

    Geosciences ; Physics ; Plasma Physics and Fusion 51 LITERATURE SURVEY OF PERMANENT MAGNET AC MOTORS AND P. PILIAY, MEMBER, IEEE, AND P. EREERE Summary: .A. Little, "Dynamic...

  10. Direct amplitude detuning measurement with ac dipole

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

    White, S.; Maclean, E.; Toms, R.

    2013-07-01T23:59:59.000Z

    In circular machines, nonlinear dynamics can impact parameters such as beam lifetime and could result in limitations on the performance reach of the accelerator. Assessing and understanding these effects in experiments is essential to confirm the accuracy of the magnetic model and improve the machine performance. A direct measurement of the machine nonlinearities can be obtained by characterizing the dependency of the tune as a function of the amplitude of oscillations (usually defined as amplitude detuning). The conventional technique is to excite the beam to large amplitudes with a single kick and derive the tune from turn-by-turn data acquired with beam position monitors. Although this provides a very precise tune measurement it has the significant disadvantage of being destructive. An alternative, nondestructive way of exciting large amplitude oscillations is to use an ac dipole. The perturbation Hamiltonian in the presence of an ac dipole excitation shows a distinct behavior compared to the free oscillations which should be correctly taken into account in the interpretation of experimental data. The use of an ac dipole for direct amplitude detuning measurement requires careful data processing allowing one to observe the natural tune of the machine; the feasibility of such a measurement is demonstrated using experimental data from the Large Hadron Collider. An experimental proof of the theoretical derivations based on measurements performed at injection energy is provided as well as an application of this technique at top energy using a large number of excitations on the same beam.

  11. Study of AC/RF properties of SRF ingot niobium

    SciTech Connect (OSTI)

    Dhakal, Pashupati; Tsindlekht, Menachem I.; Genkin, Valery M.; Ciovati, Gianluigi; Myneni, Ganapati Rao

    2013-09-01T23:59:59.000Z

    In an attempt to correlate the performance of superconducting radiofrequency cavities made of niobium with the superconducting properties, we present the results of the magnetization and ac susceptibility of the niobium used in the superconducting radiofrequency cavity fabrication. The samples were subjected to buffer chemical polishing (BCP) surface and high temperature heat treatments, typically applied to the cavities fabrications. The analysis of the results show the different surface and bulk ac conductivity for the samples subjected to BCP and heat treatment. Furthermore, the RF surface impedance is measured on the sample using a TE011 microwave cavity for a comparison to the low frequency measurements.

  12. Synchronous and Cogged Fan Belt Performance Assessment

    SciTech Connect (OSTI)

    Cutler, D.; Dean, J.; Acosta, J.

    2014-02-01T23:59:59.000Z

    The GSA Regional GPG Team commissioned the National Renewable Energy Laboratory (NREL) to perform monitoring of cogged V-belts and synchronous belts on both a constant volume and a variable air volume fan at the Byron G. Rodgers Federal Building and U.S. Courthouse in Denver, Colorado. These motor/fan combinations were tested with their original, standard V-belts (appropriately tensioned by an operation and maintenance professional) to obtain a baseline for standard operation. They were then switched to the cogged V-belts, and finally to synchronous belts. The power consumption by the motor was normalized for both fan speed and air density changes. This was necessary to ensure that the power readings were not influenced by a change in rotational fan speed or by the power required to push denser air. Finally, energy savings and operation and maintenance savings were compiled into an economic life-cycle cost analysis of the different belt options.

  13. Ac-Ac Dual Active Bridge Converter for Solid State Transformer

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    flow. The advantages of direct ac-ac conversion include fewer power conversion stages and minimized single-stage direct ac-ac power conversion to an SST. Fewer conversion stages reduce conduction loss) converter in direct ac-ac power conversion. Like a DAB converter as dc-dc power supply in [5] and [6

  14. Performance evaluation of an active filter non-regenerative AC drive

    E-Print Network [OSTI]

    Skorcz, Alex Joseph

    2009-05-15T23:59:59.000Z

    .................................................... 17 2.4 Motor Loads ......................................................................................... 18 2.4.1 Permanent Magnet Synchronous Machine (PMSM) ......... 19 viii CHAPTER Page 2.4.1.1 Mathematical Modeling... ............................................................ 46 3.3.2 Rectifier .............................................................................. 46 3.3.3 Control System ................................................................... 47 3.3.4 Inverter-Driven PMSM...

  15. Superconducting shielded core reactor with reduced AC losses

    DOE Patents [OSTI]

    Cha, Yung S.; Hull, John R.

    2006-04-04T23:59:59.000Z

    A superconducting shielded core reactor (SSCR) operates as a passive device for limiting excessive AC current in a circuit operating at a high power level under a fault condition such as shorting. The SSCR includes a ferromagnetic core which may be either closed or open (with an air gap) and extends into and through a superconducting tube or superconducting rings arranged in a stacked array. First and second series connected copper coils each disposed about a portion of the iron core are connected to the circuit to be protected and are respectively wound inside and outside of the superconducting tube or rings. A large impedance is inserted into the circuit by the core when the shielding capability of the superconducting arrangement is exceeded by the applied magnetic field generated by the two coils under a fault condition to limit the AC current in the circuit. The proposed SSCR also affords reduced AC loss compared to conventional SSCRs under continuous normal operation.

  16. AC and DC power transmission

    SciTech Connect (OSTI)

    Not Available

    1985-01-01T23:59:59.000Z

    The technical and economic assessment of AC and DC transmission systems; long distance transmission, cable transmission, system inter-connection, voltage support, reactive compensation, stabilisation of systems; parallel operation of DC links with AC systems; comparison between alternatives for particular schemes. Design and application equipment: design, testing and application of equipment for HVDC, series and shunt static compensated AC schemes, including associated controls. Installations: overall design of stations and conductor arrangements for HVDC, series and shunt static AC schemes including insulation co-ordination. System analysis and modelling.

  17. Rocking ratchet induced by pure magnetic potentials with broken reflection symmetry

    E-Print Network [OSTI]

    Perez de Lara, D.

    A ratchet effect (the rectification of an ac injected current) which is purely magnetic in origin has been observed in a superconducting-magnetic nanostructure hybrid. The hybrid consists of a superconducting Nb film in ...

  18. Spatial synchronization and extinction of species under external forcing

    E-Print Network [OSTI]

    R. E. Amritkar; Govindan Rangarajan

    2006-02-20T23:59:59.000Z

    We study the interplay between synchronization and extinction of a species. Using a general model we show that under a common external forcing, the species with a quadratic saturation term in the population dynamics first undergoes spatial synchronization and then extinction, thereby avoiding the rescue effect. This is because the saturation term reduces the synchronization time scale but not the extinction time scale. The effect can be observed even when the external forcing acts only on some locations provided there is a synchronizing term in the dynamics. Absence of the quadratic saturation term can help the species to avoid extinction.

  19. Hybrid function projective synchronization in complex dynamical networks

    SciTech Connect (OSTI)

    Wei, Qiang; Wang, Xing-yuan, E-mail: wangxy@dlut.edu.cn; Hu, Xiao-peng [Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, 116024 (China)] [Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian, 116024 (China)

    2014-02-15T23:59:59.000Z

    This paper investigates hybrid function projective synchronization in complex dynamical networks. When the complex dynamical networks could be synchronized up to an equilibrium or periodic orbit, a hybrid feedback controller is designed to realize the different component of vector of node could be synchronized up to different desired scaling function in complex dynamical networks with time delay. Hybrid function projective synchronization (HFPS) in complex dynamical networks with constant delay and HFPS in complex dynamical networks with time-varying coupling delay are researched, respectively. Finally, the numerical simulations show the effectiveness of theoretical analysis.

  20. Synchronization of hypernetworks of coupled dynamical systems

    E-Print Network [OSTI]

    Francesco Sorrentino

    2012-03-14T23:59:59.000Z

    We consider synchronization of coupled dynamical systems when different types of interactions are simultaneously present. We assume that a set of dynamical systems are coupled through the connections of two or more distinct networks (each of which corresponds to a distinct type of interaction), and we refer to such a system as a hypernetwork. Applications include neural networks formed of both electrical gap junctions and chemical synapses, the coordinated motion of shoals of fishes communicating through both vision and flow sensing, and hypernetworks of coupled chaotic oscillators. We first analyze the case of a hypernetwork formed of $m=2$ networks. We look for necessary and sufficient conditions for synchronization. We attempt at reducing the linear stability problem in a master stability function form, i.e., at decoupling the effects of the coupling functions from the structure of the networks. Unfortunately, we are unable to obtain a reduction in a master stability function form for the general case. However, we show that such a reduction is possible in three cases of interest: (i) the Laplacian matrices associated with the two networks commute; (ii) one of the two networks is unweighted and fully connected; (iii) one of the two networks is such that the coupling strength from node $i$ to node $j$ is a function of $j$ but not of $i$. Furthermore, we define a class of networks such that if either one of the two coupling networks belongs to this class, the reduction can be obtained independently of the other network. As an example of interest, we study synchronization of a neural hypernetwork for which the connections can be either chemical synapses or electrical gap junctions. We propose a generalization of our stability results to the case of hypernetworks formed of $m\\geq 2$ networks.

  1. Current Reversals and Synchronization in Coupled Ratchets

    E-Print Network [OSTI]

    U. E. Vincent; A. Kenfack; D. V. Senthilkumar; D. Mayer; J. Krths

    2010-09-26T23:59:59.000Z

    Current reversal is an intriguing phenomenon that has been central to recent experimental and theoretical investigations of transport based on ratchet mechanism. By considering a system of two interacting ratchets, we demonstrate how the coupling can be used to control the reversals. In particular, we find that current reversal that exists in a single driven ratchet system can ultimately be eliminated with the presence of a second ratchet. For specific coupling strengths a current-reversal free regime has been detected. Furthermore, in the fully synchronized state characterized by the coupling threshold $k_{th}$, a specific driving amplitude $a_{opt}$ is found for which the transport is optimum.

  2. Optimization of synchronization in gradient clustered networks

    E-Print Network [OSTI]

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

    2007-11-23T23:59:59.000Z

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

  3. Advanced control for power density maximization of the brushless DC generator

    E-Print Network [OSTI]

    Lee, Hyung-Woo

    2005-02-17T23:59:59.000Z

    of a sinusoidal EMF type of BLDC generator is very similar to the AC synchronous generator. Typically, the sinusoidal induced EMF type of generator is not considered as a BLDC, but rather a PMSM (permanent magnet synchronous machine...

  4. AC resistance measuring instrument

    DOE Patents [OSTI]

    Hof, P.J.

    1983-10-04T23:59:59.000Z

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument. 8 figs.

  5. Bipolar pulse field for magnetic refrigeration

    DOE Patents [OSTI]

    Lubell, M.S.

    1994-10-25T23:59:59.000Z

    A magnetic refrigeration apparatus includes first and second steady state magnets, each having a field of substantially equal strength and opposite polarity, first and second bodies made of magnetocaloric material disposed respectively in the influence of the fields of the first and second steady state magnets, and a pulsed magnet, concentric with the first and second steady state magnets, and having a field which cycles between the fields of the first and second steady state magnets, thereby cyclically magnetizing and demagnetizing and thus heating and cooling the first and second bodies. Heat exchange apparatus of suitable design can be used to expose a working fluid to the first and second bodies of magnetocaloric material. A controller is provided to synchronize the flow of working fluid with the changing states of magnetization of the first and second bodies. 2 figs.

  6. The Specification and Execution of Heterogeneous Synchronous Reactive Systems

    E-Print Network [OSTI]

    The Specification and Execution of Heterogeneous Synchronous Reactive Systems by Stephen Anthony in Engineering---Electrical Engineering and Computer Sciences in the GRADUATE DIVISION of the UNIVERSITY of Heterogeneous Synchronous Reactive Systems Copyright ã 1997 by Stephen Anthony Edwards #12; Abstract

  7. Turbo synchronization : an EM algorithm interpretation , C. Herzet

    E-Print Network [OSTI]

    Steendam, Heidi

    Turbo synchronization : an EM algorithm interpretation N. Noels* , C. Herzet , A. Dejonghe , V is devoted to turbo synchronization, that is to say the use of soft information to estimate parameters like carrier phase, frequency offset or timing within a turbo receiver. It is shown how maximum

  8. Joint Synchronization and Decoding Exploiting the Turbo Principle

    E-Print Network [OSTI]

    Regalia, Phillip A.

    Joint Synchronization and Decoding Exploiting the Turbo Principle John M. Walsh and C. Richard´el´ecommunications/GET 91011 Evry cedex France Abstract-- This paper investigates turbo methods for joint synchronization and decoding in pulse amplitude modulated (PAM) systems. We begin with a brief review of the turbo principle

  9. Behavioral/Systems/Cognitive Resonant Synchronization in Heterogeneous Networks of

    E-Print Network [OSTI]

    De Schutter, Erik

    with subclasses of inhibitory neurons firing phase- locked to, and often thought to generate, the rhythm (Bragin,reflectingfinitespikepropagationandsynaptictransmissiontimes.Attheresonantlevelofnetwork excitation, all neurons fire synchronously and rhythmically with a period approximately four times the mean intrinsic reso- nance can synchronize their spikes with zero phase lag, provided a finite delay separates

  10. Processus communicants Communication synchrone CSP/CCS/-calcul

    E-Print Network [OSTI]

    Grigoras, .Romulus

    Processus communicants Communication synchrone CSP/CCS/-calcul Rendez-vous étendu Ada Huitième partie Processus communicants CSP/Ada Systèmes concurrents 2 / 44 #12;Processus communicants Communication synchrone CSP/CCS/-calcul Rendez-vous étendu Ada Principes Synchronisation Désignation

  11. 1920 IEEE TRANSACTIONS ON MAGNETICS, VOL. 40, NO. 4, JULY 2004 Improving the Starting Performance of Large

    E-Print Network [OSTI]

    Mi, Chunting "Chris"

    1920 IEEE TRANSACTIONS ON MAGNETICS, VOL. 40, NO. 4, JULY 2004 Improving the Starting Performance of Large Salient-Pole Synchronous Machines Haran Karmaker, Senior Member, IEEE, and Chunting Mi, Senior of the starting system of the salient-pole synchronous machines in a pumping-generating plant. We focused

  12. Phase synchronization analysis by assessment of the phase difference gradient Martin Vejmelka

    E-Print Network [OSTI]

    Savicky, Petr

    of rhythms of self-sustained oscillatory systems. Typically when trying to identify phase synchronization of coupled self-sustained oscillatory systems, phase synchronization, given by a relation

  13. E-Print Network 3.0 - area synchronized phasor Sample Search...

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

    words: phasor measurement unit; synchronized phasor; dynamic behavior; power grid; step test... voltage and current phasors at reporting times synchronized to Coordinated...

  14. atlas magnet common: Topics by E-print Network

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

    contract No. DE-AC02-76CH00016. Abstract A common coil design concept for 2-in-1 superconduct- ing Gupta, Ramesh 30 Common energy scale for magnetism and superconductivity in...

  15. Web services synchronization health care application

    E-Print Network [OSTI]

    Limam, Hela

    2011-01-01T23:59:59.000Z

    With the advance of Web Services technologies and the emergence of Web Services into the information space, tremendous opportunities for empowering users and organizations appear in various application domains including electronic commerce, travel, intelligence information gathering and analysis, health care, digital government, etc. In fact, Web services appear to be s solution for integrating distributed, autonomous and heterogeneous information sources. However, as Web services evolve in a dynamic environment which is the Internet many changes can occur and affect them. A Web service is affected when one or more of its associated information sources is affected by schema changes. Changes can alter the information sources contents but also their schemas which may render Web services partially or totally undefined. In this paper, we propose a solution for integrating information sources into Web services. Then we tackle the Web service synchronization problem by substituting the affected information sources....

  16. Synchronous motor with soft start element formed between the motor rotor and motor output shaft to successfully synchronize loads that have high inertia and/or high torque

    DOE Patents [OSTI]

    Umans, Stephen D; Nisley, Donald L; Melfi, Michael J

    2014-10-28T23:59:59.000Z

    A line-start synchronous motor has a housing, a rotor shaft, and an output shaft. A soft-start coupling portion is operatively coupled to the output shaft and the rotor shaft. The soft-start coupling portion is configurable to enable the synchronous motor to obtain synchronous operation and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling. The synchronous motor is sufficiently rated to obtain synchronous operation and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling.

  17. Equivalent synchronization of chaos in driven and in autonomous systems

    E-Print Network [OSTI]

    M. G. Cosenza; O. Alvarez-Llamoza; G. Paredes

    2010-05-17T23:59:59.000Z

    It is shown that the synchronization behavior of a system of chaotic maps subject to either an external forcing or a coupling function of their internal variables can be inferred from the behavior of a single element in the system, which can be seen as a single drive-response map. From the conditions for stable synchronization in this single driven-map model with minimal ingredients, we find minimal conditions for the emergence of complete and generalized chaos synchronization in both driven and autonomous associated systems. Our results show that the presence of a common drive or a coupling function for all times is not indispensable for reaching synchronization in a system of chaotic oscillators, nor is the simultaneous sharing of a field, either external or endogenous, by all the elements. In the case of an autonomous system, the coupling function does not need to depend on all the internal variables for achieving synchronization and its functional form is not crucial for generalized synchronization. What becomes essential for reaching synchronization in an extended system is the sharing of some minimal information by its elements, on the average, over long times, independently of the nature (external or internal) of its source.

  18. Systems and methods for creation of conducting networks of magnetic particles through dynamic self-assembly process

    DOE Patents [OSTI]

    Snezhko, Oleksiy (Woodridge, IL); Aronson, Igor (Darien, IL); Kwok, Wai-Kwong (Downers Grove, IL)

    2011-01-25T23:59:59.000Z

    Self-assembly of magnetic microparticles in AC magnetic fields. Excitation of the system by an AC magnetic field provides a variety of patterns that can be controlled by adjusting the frequency and the amplitude of the field. At low particle densities the low-frequency magnetic excitation favors cluster phase formation, while high frequency excitation favors chains and netlike structures. For denser configurations, an abrupt transition to the network phase was obtained.

  19. Cluster synchronization in networks of neurons with chemical synapses

    SciTech Connect (OSTI)

    Juang, Jonq, E-mail: jjuang@math.nctu.edu.tw [Department of Applied Mathematics, and Center of Mathematics Modeling and Scientific Computing, National Chiao Tung University, Hsinchu, Taiwan and National Center for Theoretical Sciences, Hsinchu, Taiwan (China)] [Department of Applied Mathematics, and Center of Mathematics Modeling and Scientific Computing, National Chiao Tung University, Hsinchu, Taiwan and National Center for Theoretical Sciences, Hsinchu, Taiwan (China); Liang, Yu-Hao, E-mail: moonsea.am96g@g2.nctu.edu.tw [Department of Mathematics, National Tsing Hua University, Hsinchu, Taiwan (China)] [Department of Mathematics, National Tsing Hua University, Hsinchu, Taiwan (China)

    2014-03-15T23:59:59.000Z

    In this work, we study the cluster synchronization of chemically coupled and generally formulated networks which are allowed to be nonidentical. The sufficient condition for the existence of stably synchronous clusters is derived. Specifically, we only need to check the stability of the origins of m decoupled linear systems. Here, m is the number of subpopulations. Examples of nonidentical networks such as Hindmarsh-Rose (HR) neurons with various choices of parameters in different subpopulations, or HR neurons in one subpopulation and FitzHugh-Nagumo neurons in the other subpopulation are provided. Explicit threshold for the coupling strength that guarantees the stably cluster synchronization can be obtained.

  20. Failure Detection with Booting in Partially Synchronous Systems

    E-Print Network [OSTI]

    Failure Detection with Booting in Partially Synchronous Systems Josef Widder1 , G´erard Le Lann2 implementation with respect to failure detection time, but also works during the system booting phase. 1

  1. Parameter Mismatches, Chaos Synchronization and Fast Dynamic Logic Gates

    E-Print Network [OSTI]

    E. M. Shahverdiev

    2009-07-02T23:59:59.000Z

    By using chaos synchronization between non-identical multiple time delay semiconductor lasers with optoelectronic feedbacks, we demonstrate numerically how fast dynamic logic gates can be constructed. The results may be helpful to obtain a computational hardware with reconfigurable properties.

  2. Synchronized Collective Behavior via Low-cost Communication

    E-Print Network [OSTI]

    Hai-Tao Zhang; Michael ZhiQiang Chen; Tao Zhou

    2007-07-23T23:59:59.000Z

    An important natural phenomenon surfaces that satisfactory synchronization of self-driven particles can be achieved via sharply reduced communication cost, especially for high density particle groups with low external noise. Statistical numerical evidence illustrates that a highly efficient manner is to distribute the communication messages as evenly as possible along the whole dynamic process, since it minimizes the communication redundancy. More surprisingly, it is discovered that there exist some abnormal regions where moderately decreasing the communication cost can even improve the synchronization performance. A phase diagram on the noise-density parameter space is given, where the dynamical behaviors can be divided into three qualitatively different phases: normal phase where better synchronization corresponds to higher communication cost, abnormal phase where moderately decreasing communication cost could even improve the synchronization, and the disordered phase where no coherence among individuals is observed.

  3. Synchronized flux corrected remapping for ALE methods Richard Liska a,

    E-Print Network [OSTI]

    Liska, Richard

    simultaneously to treat all quanti- ties in the system at once, thus we call our method synchronized FCR (SFCR). The SFCR method has been developed in [13] for mass and momentum with bounds in density and velocity. Here

  4. Performance analysis of synchronous machines under dynamic eccentricity

    E-Print Network [OSTI]

    Al-Nuaim, Nabil Abdulaziz

    1996-01-01T23:59:59.000Z

    The performance of salient pole synchronous machines under eccentric rotors is studied. Relationships between stator and rotor current induced harmonics and dynamic eccentricity are investigated. The winding function theory has been modified...

  5. Experimental Synchronization of Spatiotemporal Chaos in Nonlinear Optics

    E-Print Network [OSTI]

    P. L. Ramazza; U. Bortolozzo; S. Boccaletti

    2005-02-10T23:59:59.000Z

    We demonstrate that a unidirectional coupling between a pattern forming system and its replica induces complete synchronization of the slave to the master system onto a spatiotemporal chaotic state.

  6. Projective synchronization in fractional order chaotic systems and its control

    E-Print Network [OSTI]

    Chunguang Li

    2006-04-24T23:59:59.000Z

    The chaotic dynamics of fractional (non-integer) order systems have begun to attract much attention in recent years. In this paper, we study the projective synchronization in two coupled fractional order chaotic oscillators. It is shown that projective synchronization can also exist in coupled fractional order chaotic systems. A simple feedback control method for controlling the scaling factor onto a desired value is also presented.

  7. Low latency memory access and synchronization

    DOE Patents [OSTI]

    Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton On Hudson, NY); Coteus, Paul W. (Yorktown Heights, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Hoenicke, Dirk (Ossining, NY); Ohmacht, Martin (Brewster, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY); Takken, Todd E. (Mount Kisco, NY), Vranas; Pavlos M. (Bedford Hills, NY)

    2010-10-19T23:59:59.000Z

    A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Bach processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processor only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple prefetching for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefetch rather than some other predictive algorithm. This enables hardware to effectively prefetch memory access patterns that are non-contiguous, but repetitive.

  8. Low latency memory access and synchronization

    DOE Patents [OSTI]

    Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton On Hudson, NY); Coteus, Paul W. (Yorktown Heights, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Hoenicke, Dirk (Ossining, NY); Ohmacht, Martin (Brewster, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY); Takken, Todd E. (Mount Kisco, NY); Vranas, Pavlos M. (Bedford Hills, NY)

    2007-02-06T23:59:59.000Z

    A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Each processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processor only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple prefetching for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefetch rather than some other predictive algorithm. This enables hardware to effectively prefetch memory access patterns that are non-contiguous, but repetitive.

  9. Exchange 13/14 www.ed.ac.uk

    E-Print Network [OSTI]

    Herrmann, Samuel

    : Studyabroad@ed.ac.uk Outgoing Students: Sharyn Bennet Email: Erasmus.outgoing@ed.ac.uk Head of Study Abroad

  10. Web https://ms.ecc.utokyo.ac.jp/ (POP) popd.ecc.utokyo.ac.jp

    E-Print Network [OSTI]

    Katsumoto, Shingo

    ; 2 233 #12; (POP) popd.ecc.utokyo.ac.jp SSL995 (IMAP) imapd.ecc.utokyo.ac.jp SSL993 sbmsd.ecc.utokyo.ac.jp SSL465 @ 1. MailHosting D 2. 200MB 400MB 3. POPIMAP IMAPPOP 200MB400MB 3 233 #12;Thunderbird 3 4 233 #12; (POP) popd.ecc.utokyo.ac.jp SSL995 (IMAP) imapd.ecc.utokyo.ac.jp SSL993

  11. CD54AC08, CD74AC08 QUADRUPLE 2-INPUT POSITIVE-AND GATES

    E-Print Network [OSTI]

    Kretchmar, R. Matthew

    SOIC M Tube CD74AC08M AC08M­55°C to 125°C SOIC ­ M Tape and reel CD74AC08M96 AC08M CDIP ­ F Tube CD54AC-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed. 2. The package thermal impedance

  12. Superconducting magnetic energy storage for asynchronous electrical systems

    DOE Patents [OSTI]

    Boenig, H.J.

    1984-05-16T23:59:59.000Z

    It is an object of the present invention to provide superconducting magnetic energy storage for a plurality of asynchronous electrical systems. It is a further object of the present invention to provide load leveling and stability improvement in a plurality of independent ac systems using a single superconducting magnetic energy storage coil.

  13. Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits

    DOE Patents [OSTI]

    Campbell, Ann. N. (13170-B Central SE #188, Albuquerque, NM 87123); Anderson, Richard E. (2800 Tennessee NE, Albuquerque, NM 87110); Cole, Jr., Edward I. (2116 White Cloud NE, Albuquerque, NM 87112)

    1995-01-01T23:59:59.000Z

    A magnetic force microscopy method and improved magnetic tip for detecting and quantifying internal magnetic fields resulting from current of integrated circuits. Detection of the current is used for failure analysis, design verification, and model validation. The interaction of the current on the integrated chip with a magnetic field can be detected using a cantilevered magnetic tip. Enhanced sensitivity for both ac and dc current and voltage detection is achieved with voltage by an ac coupling or a heterodyne technique. The techniques can be used to extract information from analog circuits.

  14. Magnetic force microscopy method and apparatus to detect and image currents in integrated circuits

    DOE Patents [OSTI]

    Campbell, A.N.; Anderson, R.E.; Cole, E.I. Jr.

    1995-11-07T23:59:59.000Z

    A magnetic force microscopy method and improved magnetic tip for detecting and quantifying internal magnetic fields resulting from current of integrated circuits are disclosed. Detection of the current is used for failure analysis, design verification, and model validation. The interaction of the current on the integrated chip with a magnetic field can be detected using a cantilevered magnetic tip. Enhanced sensitivity for both ac and dc current and voltage detection is achieved with voltage by an ac coupling or a heterodyne technique. The techniques can be used to extract information from analog circuits. 17 figs.

  15. Synchronization in Complex Oscillator Networks and Smart Grids

    SciTech Connect (OSTI)

    Dorfler, Florian [Los Alamos National Laboratory; Chertkov, Michael [Los Alamos National Laboratory; Bullo, Francesco [Center for Control, Dynamical Systems and Computation, University of California at Santa Babara, Santa Barbara CA

    2012-07-24T23:59:59.000Z

    The emergence of synchronization in a network of coupled oscillators is a fascinating topic in various scientific disciplines. A coupled oscillator network is characterized by a population of heterogeneous oscillators and a graph describing the interaction among them. It is known that a strongly coupled and sufficiently homogeneous network synchronizes, but the exact threshold from incoherence to synchrony is unknown. Here we present a novel, concise, and closed-form condition for synchronization of the fully nonlinear, non-equilibrium, and dynamic network. Our synchronization condition can be stated elegantly in terms of the network topology and parameters, or equivalently in terms of an intuitive, linear, and static auxiliary system. Our results significantly improve upon the existing conditions advocated thus far, they are provably exact for various interesting network topologies and parameters, they are statistically correct for almost all networks, and they can be applied equally to synchronization phenomena arising in physics and biology as well as in engineered oscillator networks such as electric power networks. We illustrate the validity, the accuracy, and the practical applicability of our results in complex networks scenarios and in smart grid applications.

  16. Chaos Pass Filter: Linear Response of Synchronized Chaotic Systems

    E-Print Network [OSTI]

    Steffen Zeeb; Johannes Kestler; Ido Kanter; Wolfgang Kinzel

    2013-01-29T23:59:59.000Z

    The linear response of synchronized time-delayed chaotic systems to small external perturbations, i.e., the phenomenon of chaos pass filter, is investigated for iterated maps. The distribution of distances, i.e., the deviations between two synchronized chaotic units due to external perturbations on the transfered signal, is used as a measure of the linear response. It is calculated numerically and, for some special cases, analytically. Depending on the model parameters this distribution has power law tails in the region of synchronization leading to diverging moments of distances. This is a consequence of multiplicative and additive noise in the corresponding linear equations due to chaos and external perturbations. The linear response can also be quantified by the bit error rate of a transmitted binary message which perturbs the synchronized system. The bit error rate is given by an integral over the distribution of distances and is calculated analytically and numerically. It displays a complex nonmonotonic behavior in the region of synchronization. For special cases the distribution of distances has a fractal structure leading to a devil's staircase for the bit error rate as a function of coupling strength. The response to small harmonic perturbations shows resonances related to coupling and feedback delay times. A bi-directionally coupled chain of three units can completely filtered out the perturbation. Thus the second moment and the bit error rate become zero.

  17. Synchronization in Complex Oscillator Networks and Smart Grids

    E-Print Network [OSTI]

    Florian Drfler; Michael Chertkov; Francesco Bullo

    2012-07-31T23:59:59.000Z

    The emergence of synchronization in a network of coupled oscillators is a fascinating topic in various scientific disciplines. A coupled oscillator network is characterized by a population of heterogeneous oscillators and a graph describing the interaction among them. It is known that a strongly coupled and sufficiently homogeneous network synchronizes, but the exact threshold from incoherence to synchrony is unknown. Here we present a novel, concise, and closed-form condition for synchronization of the fully nonlinear, non-equilibrium, and dynamic network. Our synchronization condition can be stated elegantly in terms of the network topology and parameters, or equivalently in terms of an intuitive, linear, and static auxiliary system. Our results significantly improve upon the existing conditions advocated thus far, they are provably exact for various interesting network topologies and parameters, they are statistically correct for almost all networks, and they can be applied equally to synchronization phenomena arising in physics and biology as well as in engineered oscillator networks such as electric power networks. We illustrate the validity, the accuracy, and the practical applicability of our results in complex networks scenarios and in smart grid applications.

  18. Time Synchronization in Hierarchical TESLA Wireless Sensor Networks

    SciTech Connect (OSTI)

    Jason L. Wright; Milos Manic

    2009-08-01T23:59:59.000Z

    Time synchronization and event time correlation are important in wireless sensor networks. In particular, time is used to create a sequence events or time line to answer questions of cause and effect. Time is also used as a basis for determining the freshness of received packets and the validity of cryptographic certificates. This paper presents secure method of time synchronization and event time correlation for TESLA-based hierarchical wireless sensor networks. The method demonstrates that events in a TESLA network can be accurately timestamped by adding only a few pieces of data to the existing protocol.

  19. Improving the dynamic performance of a complex AC/DC system by HVDC control modifications

    SciTech Connect (OSTI)

    Hammad, A.E. (ABB Power Systems, Baden (CH)); Gagnon, J. (Hydro Quebec, Montreal (CA)); McCallum, D. (IREQ, Montreal (CA))

    1990-10-01T23:59:59.000Z

    The power system of Hydro-Quebec has a peak load of approximately 27 GW. The great distance between the production sites and the load centers introduces stability limitations, which is the reason why the Quebec grid cannot be economically synchronized (through ac transmission with limited capacity) with the U.S. northeastern network. Power exports are therefore dependent on the use of HVDC links of which Hydro-Quebec now possesses five, for a capacity of over 2600 MW. Such a capacity will again soon increase. At the moment, the Chateauguay scheme has the largest HVDC capacity. It transfers 1000 MW by means of two Back-to-Back converter blocks. Various automatic control systems are installed on the Chateauguay scheme owing to the fact that a single circuit of a 765 kV ac line transmits the output of both the HVDC converter stations as well as the output from Beauharnois hydro generating station. Such controls have performed satisfactorily since 1984. However, a remarkable improvement of the overall ac/dc system dynamic performance can be gained by making certain modifications in some of these HVDC system controls. This paper presents the salient features of such control modifications, currently under consideration, using the results of an investigation by digital and analogue simulations that demonstrate the achieved improvements.

  20. New advances in designing energy efficient time synchronization schemes for wireless sensor networks

    E-Print Network [OSTI]

    Noh, Kyoung Lae

    2009-05-15T23:59:59.000Z

    presents significant energy saving. Finally, this dissertation introduces a novel adaptive time synchronization protocol, named the Adaptive Multi-hop Timing Synchronization (AMTS). According to the current network status, AMTS optimizes crucial network...

  1. Analysis of electrical signatures in synchronous generators characterized by bearing faults

    E-Print Network [OSTI]

    Choi, Jae-Won

    2009-05-15T23:59:59.000Z

    Synchronous generators play a vital role in power systems. One of the major mechanical faults in synchronous generators is related to bearings. The popular vibration analysis method has been utilized to detect bearing faults for years. However...

  2. Correspondence-free Synchronization and Reconstruction in a Non-rigid Scene

    E-Print Network [OSTI]

    Wolf, Lior

    sections. First, we show how to synchronize two vidoe 2 #12;sequences. 1.1 Previous work Using several

  3. Ad Hoc Synchronization Considered Harmful Weiwei Xiong+, Soyeon Park, Jiaqi Zhang, Yuanyuan Zhou, Zhiqiang Ma*

    E-Print Network [OSTI]

    Zhou, Yuanyuan

    Ad Hoc Synchronization Considered Harmful Weiwei Xiong+, Soyeon Park, Jiaqi Zhang, Yuanyuan Zhou Abstract Many synchronizations in existing multi­threaded pro­ grams are implemented in an ad hoc way. The first part of this paper does a comprehensive characteristic study of ad hoc synchronizations

  4. Gravitational resonance spectroscopy with an oscillating magnetic field gradient in the GRANIT flow through arrangement

    E-Print Network [OSTI]

    G. Pignol; S. Baessler; V. V. Nesvizhevsky; K. Protasov; D. Rebreyend; A. Yu. Voronin

    2014-08-05T23:59:59.000Z

    Gravitational resonance spectroscopy consists in measuring the energy spectrum of bouncing ultracold neutrons above a mirror by inducing resonant transitions between different discrete quantum levels. We discuss how to induce the resonances with a flow through arrangement in the GRANIT spectrometer, excited by an oscillating magnetic field gradient. The spectroscopy could be realized in two distinct modes (so called DC and AC) using the same device to produce the magnetic excitation. We present calculations demonstrating the feasibility of the newly proposed AC mode.

  5. A Synchronous Approach to Reactive System Design1 Charles Andr

    E-Print Network [OSTI]

    André, Charles

    our experience teaching discrete-event reactive systems to Electrical Engineering students. The courseA Synchronous Approach to Reactive System Design1 Charles André I3S Laboratory ­ UNSA/CNRS BP 121 This paper was presented at the 12th EAEEIE Annual Conf., 14-16 May 2001, Nancy (France). Abstract Reactive

  6. Synchronization of PPM over Wideband Multipath Dana Porrat

    E-Print Network [OSTI]

    Porrat, Dana

    of Electrical Engineering University of Southern California Los Angeles, CA USA ubli@ucs.edu Abstract amount of multi-path in UWB radio channels, methods for harnessing such diversity when the channel potential. We have shown in [6] that in the limit of large bandwidth, threshold based synchronizers cannot

  7. Communication using Synchronization of Chaos in Semiconductor Lasers with optoelectronic

    E-Print Network [OSTI]

    Illing, Lucas

    Communication using Synchronization of Chaos in Semiconductor Lasers with optoelectronic feedback S. The Chaos in the single-mode semiconductor lasers is generated by means of an optoelectronic feedback with optoelectronic feedback has been demonstrated for quite slow data rates by using chaotic wavelength fluctuations

  8. Exploring Synchronization in Complex Oscillator Networks Florian Dorfler Francesco Bullo

    E-Print Network [OSTI]

    Bullo, Francesco

    Exploring Synchronization in Complex Oscillator Networks Florian D¨orfler Francesco Bullo Abstract work supported by NSF grants IIS- 0904501 and CPS-1135819. Florian D¨orfler and Francesco Bullo: {dorfler,bullo}@engineering.ucsb.edu a phase angle i S1 and has a preferred natural rotation frequency i

  9. Synchronization of Power Networks: Network Reduction and Effective Resistance

    E-Print Network [OSTI]

    Bullo, Francesco

    Synchronization of Power Networks: Network Reduction and Effective Resistance Florian D¨orfler Barbara, Santa Barbara, CA 93106 USA (e-mail: {dorfler,bullo}@engineering.ucsb.edu). Abstract in a network-reduced power system. Among other things, D¨orfler and Bullo (2010b) provided a solution

  10. Conditions for synchronization in Josephson-junction arrays

    SciTech Connect (OSTI)

    Chernikov, A.A.; Schmidt, G. [Stevens Institute of Technology, Hoboken, New Jersey 07030 (United States)] [Stevens Institute of Technology, Hoboken, New Jersey 07030 (United States)

    1995-10-01T23:59:59.000Z

    An effective perturbation theoretical method has been developed to study the dynamics of Josephson-junction series arrays. It is shown that the inclusion of junction capacitances, which is often ignored, has a significant impact on synchronization. Comparison of analytic with computational results over a wide range of parameters shows excellent agreement.

  11. ESC: Energy Synchronized Communication in Sustainable Sensor Networks

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    ESC: Energy Synchronized Communication in Sustainable Sensor Networks Yu Gu, Ting Zhu and Tian He Abstract--With advances in energy harvesting techniques, it is now feasible to build sustainable sensor of sustainable sensor networks is to effectively utilize a continuous stream of ambient energy. Instead

  12. Attack-Resilient Time Synchronization for Wireless Sensor Networks

    E-Print Network [OSTI]

    Yener, Aylin

    Attack-Resilient Time Synchronization for Wireless Sensor Networks Hui Song, Sencun Zhu in sensor networks were not designed with security in mind, thus leaving them vulnerable to security attacks. In this paper, we first identify various attacks that are effective to several representative time

  13. Semantic Synchronization in a Persistent Object System Library

    E-Print Network [OSTI]

    Wolf, Alexander L.

    constraints on a database, and the database management system (DBMS) synchronizes concurrent transactions transactions. Most commonly, a DBMS uses a two-phase locking protocol to enforce serializability. Each transaction requests locks according to the protocol, and the DBMS evaluates each request for con ict

  14. Leakage-Aware Energy Synchronization for Wireless Sensor Networks

    E-Print Network [OSTI]

    Zhang, Zhi-Li

    Leakage-Aware Energy Synchronization for Wireless Sensor Networks Ting Zhu, Ziguo Zhong, Yu Gu-capacitor as the only energy storage unit. To efficiently use the harvested energy, we design and imple- ment leakage-aware con- trol can effectively utilize energy that could otherwise leak away. Nodes running leakage-aware

  15. Synchronization of Turbo Codes Based on Online Statistics

    E-Print Network [OSTI]

    Valenti, Matthew C.

    Synchronization of Turbo Codes Based on Online Statistics Jian Sun and Matthew C. Valenti Wireless 26506-6109 email: [jian,mvalenti]@csee.wvu.edu, phone: 304-293-0405, fax: 304-293-8602 Abstract-- Turbo. Since turbo codes are intended to be deployed in environments with very low SNR, conventional

  16. Communication and Synchronization in Multithreaded Reconfigurable Computing Systems

    E-Print Network [OSTI]

    Hellebrand, Sybille

    design technique of modeling hardware accelerators as passive co- processors to the system CPU operating system services, instead of passive coprocessors that can simply be called from software levels: First, hardware circuits need to communicate and synchronize on a low level with the operating

  17. Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications

    E-Print Network [OSTI]

    of automated register­transfer level (RTL) VHDL code generation from synchronous dataflow (SDF) graph for mapping applications specified in SDF to parallel digital hardware implementations. Two styles synthesis from SDF graphs is presented. In order to minimize cost while meeting performance require­ ments

  18. Synchronous Black Hole Search in Directed Graphs Adrian Kosowski

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Synchronous Black Hole Search in Directed Graphs Adrian Kosowski Alfredo Navarra Cristina M called black hole nodes, and once a robot enters in one of them, it is destroyed. The goal is to find supported by the Italian CNR Short-Term Mobility Program. A. Kosowski was supported Polish Ministry Grant N

  19. Conditions for synchronization in Josephson-junction arrays

    SciTech Connect (OSTI)

    Chernikov, A.A.; Schmidt, G. [Stevens Institute of Technology, Hoboken, NJ (United States)

    1995-12-31T23:59:59.000Z

    An effective perturbation theoretical method has been developed to study the dynamics of Josephson Junction series arrays. It is shown that the inclusion of Junction capacitances, often ignored, has a significant impact on synchronization. Comparison of analytic with computational results over a wide range of parameters shows excellent agreement.

  20. CD54AC02, CD74AC02 QUADRUPLE 2-INPUT POSITIVE-NOR GATES

    E-Print Network [OSTI]

    Kretchmar, R. Matthew

    to 125°C SOIC ­ M Tape and reel CD74AC02M96 AC02M CDIP ­ F Tube CD54AC02F3A CD54AC02F3A Package drawings-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed. 2. The package thermal impedance

  1. CD54AC32, CD74AC32 QUADRUPLE 2-INPUT POSITIVE-OR GATES

    E-Print Network [OSTI]

    Kretchmar, R. Matthew

    Tape and reel CD74AC32M96 AC32M CDIP ­ F Tube CD54AC32F3A CD54AC32F3A Package drawings, standard-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed. 2. The package thermal impedance

  2. AC corrosion on cathodically protected steel.

    E-Print Network [OSTI]

    Torstensen, Andreas

    2012-01-01T23:59:59.000Z

    ?? This report deals with the effect of alternating current on cathodically protected steel. AC corrosion has become relevant in the offshore industry due to (more)

  3. High frequency AC power converter for low voltage circuits

    E-Print Network [OSTI]

    Salazar, Nathaniel Jay Tobias

    2012-01-01T23:59:59.000Z

    This thesis presents a novel AC power delivery architecture that is suitable for VHF frequency (50-100MHz) polyphase AC/DC power conversion in low voltage integrated circuits. A complete AC power delivery architecture was ...

  4. Time-delayed coupled chaotic semiconductor lasers show new types of synchronization: Experiment and theory

    E-Print Network [OSTI]

    Aviad, Y; Zigzag, M; Rosenbluh, M; Kanter, I

    2011-01-01T23:59:59.000Z

    Topologies of two, three and four time-delay-coupled chaotic semiconductor lasers are experimentally and theoretically found to show new types of synchronization. Shifted zero-lag synchronization is observed for two lasers separated by long distances even when their self-feedback delays are not equal. Shifted sub-lattice synchronization is observed for quadrilateral geometries while the equilateral triangle is zero-lag synchronized. Generalized zero-lag synchronization, without the limitation of precisely matched delays, opens possibilities for advanced multi-user communication protocols.

  5. Time-delayed coupled chaotic semiconductor lasers show new types of synchronization: Experiment and theory

    E-Print Network [OSTI]

    Y. Aviad; I. Reidler; M. Zigzag; M. Rosenbluh; I. Kanter

    2011-11-28T23:59:59.000Z

    Topologies of two, three and four time-delay-coupled chaotic semiconductor lasers are experimentally and theoretically found to show new types of synchronization. Shifted zero-lag synchronization is observed for two lasers separated by long distances even when their self-feedback delays are not equal. Shifted sub-lattice synchronization is observed for quadrilateral geometries while the equilateral triangle is zero-lag synchronized. Generalized zero-lag synchronization, without the limitation of precisely matched delays, opens possibilities for advanced multi-user communication protocols.

  6. Alamouti {yjdong, sky6174}@ccl.snu.ac.kr, jsno@snu.ac.kr, djshin@hanyang.ac.kr

    E-Print Network [OSTI]

    No, Jong-Seon

    @snu.ac.kr, djshin@hanyang.ac.kr (soft-decision-and-forward: SDF) . SDF . Alamouti , . (amplify-and-forward: AF) . , SDF AF . 1. . (source: S-decision-and-forward: SDF) . SDF R S phase, phase 1 phase 2 . Phase 1, S R D , phase 2 R D . , S D

  7. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell...

    Energy Savers [EERE]

    (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results This...

  8. Method of driving liquid flow at or near the free surface using magnetic microparticles

    DOE Patents [OSTI]

    Snezhko, Oleksiy (Woodridge, IL); Aronson, Igor (Darien, IL); Kwok, Wai-Kwong (Evanston, IL); Belkin, Maxim V. (Woodridge, IL)

    2011-10-11T23:59:59.000Z

    The present invention provides a method of driving liquid flow at or near a free surface using self-assembled structures composed of magnetic particles subjected to an external AC magnetic field. A plurality of magnetic particles are supported at or near a free surface of liquid by surface tension or buoyancy force. An AC magnetic field traverses the free surface and dipole-dipole interaction between particles produces in self-assembled snake structures which oscillate at the frequency of the traverse AC magnetic field. The snake structures independently move across the free surface and may merge with other snake structures or break up and coalesce into additional snake structures experiencing independent movement across the liquid surface. During this process, the snake structures produce asymmetric flow vortices across substantially the entirety of the free surface, effectuating liquid flow across the free surface.

  9. (5202) e-mail: takasaki.midori@ocha.ac.jp (5201) e-mail: iwasaki.ogihara.chizuru@ocha.ac.jp

    E-Print Network [OSTI]

    Matsuzaki, Katsuhiko

    .chika@ocha.ac.jp = (5215) e-mail: schwartz.laure@ocha.ac.jp (5182) e-mail: kanda.yutsuki@ocha.ac.jp (5181) e

  10. Electro-Mechanical Resonant Magnetic Field Sensor

    E-Print Network [OSTI]

    Temnykh, A B; Temnykh, Alexander B.; Lovelace, Richard V. E.

    2002-01-01T23:59:59.000Z

    We describe a new type of magnetic field sensor which is termed an Electro-Mechanical Resonant Sensor (EMRS). The key part of this sensor is a small conductive elastic element with low damping rate and therefore a high Q fundamental mode of frequency $f_1$. An AC current is driven through the elastic element which, in the presence of a magnetic field, causes an AC force on the element. When the frequency of the AC current matches the resonant frequency of the element, maximum vibration of the element occurs and this can be measured precisely by optical means. We have built and tested a model sensor of this type using for the elastic element a length of copper wire of diameter 0.030 mm formed into a loop shape. The wire motion was measured using a light emitting diode photo-transistor assembly. This sensor demonstrated a sensitivity better than 0.001G for an applied magnetic field of $ \\sim 1$G and a good selectivity for the magnetic field direction. The sensitivity can be easily improved by a factor of $\\sim ...

  11. Optical synchronization system for femtosecond X-ray sources

    DOE Patents [OSTI]

    Wilcox, Russell B. (El Cerrito, CA); Holzwarth, Ronald (Munich, DE)

    2011-12-13T23:59:59.000Z

    Femtosecond pump/probe experiments using short X-Ray and optical pulses require precise synchronization between 100 meter-10 km separated lasers in a various experiments. For stabilization in the hundred femtosecond range a CW laser is amplitude modulated at 1-10 GHz, the signal retroreflected from the far end, and the relative phase used to correct the transit time with various implementations. For the sub-10 fsec range the laser frequency itself is upshifted 55 MHz with an acousto-optical modulator, retroreflected, upshifted again and phase compared at the sending end to a 110 MHz reference. Initial experiments indicate less than 1 fsec timing jitter. To lock lasers in the sub-10 fs range two single-frequency lasers separated by several teraHertz will be lock to a master modelocked fiber laser, transmit the two frequencies over fiber, and lock two comb lines of a slave laser to these frequencies, thus synchronizing the two modelocked laser envelopes.

  12. Apparatus, system, and method for synchronizing a timer key

    DOE Patents [OSTI]

    Condit, Reston A; Daniels, Michael A; Clemens, Gregory P; Tomberlin, Eric S; Johnson, Joel A

    2014-04-22T23:59:59.000Z

    A timer key relating to monitoring a countdown time of a countdown routine of an electronic device is disclosed. The timer key comprises a processor configured to respond to a countdown time associated with operation of the electronic device, a display operably coupled with the processor, and a housing configured to house at least the processor. The housing has an associated structure configured to engage with the electronic device to share the countdown time between the electronic device and the timer key. The processor is configured to begin a countdown routine based at least in part on the countdown time, wherein the countdown routine is at least substantially synchronized with a countdown routine of the electronic device when the timer key is removed from the electronic device. A system and method for synchronizing countdown routines of a timer key and an electronic device are also disclosed.

  13. Synchronous parallel kinetic Monte Carlo Diffusion in Heterogeneous Systems

    SciTech Connect (OSTI)

    Martinez Saez, Enrique [Los Alamos National Laboratory; Hetherly, Jeffery [Los Alamos National Laboratory; Caro, Jose A [Los Alamos National Laboratory

    2010-12-06T23:59:59.000Z

    A new hybrid Molecular Dynamics-kinetic Monte Carlo algorithm has been developed in order to study the basic mechanisms taking place in diffusion in concentrated alloys under the action of chemical and stress fields. Parallel implementation of the k-MC part based on a recently developed synchronous algorithm [1. Compo Phys. 227 (2008) 3804-3823] resorting on the introduction of a set of null events aiming at synchronizing the time for the different subdomains, added to the parallel efficiency of MD, provides the computer power required to evaluate jump rates 'on the flight', incorporating in this way the actual driving force emerging from chemical potential gradients, and the actual environment-dependent jump rates. The time gain has been analyzed and the parallel performance reported. The algorithm is tested on simple diffusion problems to verify its accuracy.

  14. Spontaneous synchronization driven by energy transport in interconnected networks

    E-Print Network [OSTI]

    Vincenzo Nicosia; Per Sebastian Skardal; Vito Latora; Alex Arenas

    2015-02-26T23:59:59.000Z

    Understanding dynamical processes on networks is an important area of research in complex systems, with far reaching implications and applications in many real-world cases. Here we introduce and study a model of intertwined dynamics on interconnected networks, inspired by the human brain, which consists of bidirectionally coupled synchronization and energy transport processes. Remarkably, the proposed model allows the emergence of spontaneous switch-like synchronization transitions driven by the energy transport dynamics, which qualitatively mirror the transitions observed in human brain dynamics between resting-state and cognitive activity. We provide a steady-state analytical explanation for the observed behavior and show that the switch-like transition is robust over a wide range of model parameters and network topologies. Finally, we suggest that the complexity inherent in other interconnected dynamical processes might be responsible for various other emergent behaviors observed in natural systems.

  15. Synchronization of piece-wise continuous systems of fractional order

    E-Print Network [OSTI]

    Marius-F. Danca

    2014-08-19T23:59:59.000Z

    The aim of this study is to prove analytically that synchronization of a piece-wise continuous class of systems of fractional order can be achieved. Based on our knowledge, there are no numerical methods to integrate differential equations with discontinuous right hand side of fractional order which model these systems. Therefore, via Filippov's regularization [1] and Cellina's Theorem [2,3], we prove that the initial value problem can be converted into a continuous problem of fractional-order, to which numerical methods for fractional orders apply. In this way, the synchronization problem transforms into a standard problem for continuous systems of fractional order. Three examples of fractional-order piece-wise systems are considered: Sprott system, Chen and Shimizu-Morioka system.

  16. Kuramoto model of synchronization: Equilibrium and nonequilibrium aspects

    E-Print Network [OSTI]

    Shamik Gupta; Alessandro Campa; Stefano Ruffo

    2014-08-27T23:59:59.000Z

    Recently, there has been considerable interest in the study of spontaneous synchronization, particularly within the framework of the Kuramoto model. The model comprises oscillators with distributed natural frequencies interacting through a mean-field coupling, and serves as a paradigm to study synchronization. In this review, we put forward a general framework in which we discuss in a unified way known results with more recent developments obtained for a generalized Kuramoto model that includes inertial effects and noise. We describe the model from a different perspective, highlighting the long-range nature of the interaction between the oscillators, and emphasizing the equilibrium and out-of-equilibrium aspects of its dynamics from a statistical physics point of view. In the first main section, we introduce the model and discuss for the noiseless and noisy dynamics and unimodal frequency distributions the synchronization transition that occurs in the stationary state. In the second section, we introduce the generalized model, and discuss its synchronization phase diagram for unimodal frequency distributions. In the third section, we describe deviations from the mean-field setting of the Kuramoto model by considering the generalized dynamics on a one-dimensional periodic lattice on the sites of which the oscillators reside and interact with a coupling that decays as an inverse power-law of their separation. For two specific cases, namely, in the absence of noise and inertia, and in the case when the natural frequencies are the same for all the oscillators, we discuss how the long-time transition to synchrony is governed by the dynamics of the mean-field mode (zero Fourier mode) of the spatial distribution of the oscillator phases.

  17. The complex planetary synchronization structure of the solar system

    E-Print Network [OSTI]

    Nicola Scafetta

    2014-01-16T23:59:59.000Z

    The complex planetary synchronization structure of the solar system, which since Pythagoras of Samos (ca. 570-495 BC) is known as the music of the spheres, is briefly reviewed from the Renaissance up to contemporary research. Copernicus' heliocentric model from 1543 suggested that the planets of our solar system form a kind of mutually ordered and quasi-synchronized system. From 1596 to 1619 Kepler formulated preliminary mathematical relations of approximate commensurabilities among the planets, which were later reformulated in the Titius-Bode rule (1766-1772) that successfully predicted the orbital position of Ceres and Uranus. Following the discovery of the ~11 yr sunspot cycle, in 1859 Wolf suggested that the observed solar variability could be approximately synchronized with the orbital movements of Venus, Earth, Jupiter and Saturn. Modern research have further confirmed that: (1) the planetary orbital periods can be approximately deduced from a simple system of resonant frequencies; (2) the solar system oscillates with a specific set of gravitational frequencies, and many of them (e.g. within the range between 3 yr and 100 yr) can be approximately constructed as harmonics of a base period of ~178.38 yr; (3) solar and climate records are also characterized by planetary harmonics from the monthly to the millennia time scales. This short review concludes with an emphasis on the contribution of the author's research on the empirical evidences and physical modeling of both solar and climate variability based on astronomical harmonics. The general conclusion is that the solar system works as a resonator characterized by a specific harmonic planetary structure that synchronizes also the Sun's activity and the Earth's climate.

  18. Laser synchronized high-speed shutter for spectroscopic application

    DOE Patents [OSTI]

    Miles, Paul C. (Tracy, CA); Porter, Eldon L. (Tracy, CA); Prast, Thomas L. (Livermore, CA); Sunnarborg, Duane A. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A fast mechanical shutter, based on rotating chopper wheels, has been designed and implemented to shutter the entrance slit of a spectrograph. This device enables an exposure time of 9 .mu.s to be achieved for a 0.8 mm wide spectrograph entrance slit, achieves 100% transmission in the open state, and an essentially infinite extinction ratio. The device further incorporates chopper wheel position sensing electronics to permit the synchronous triggering of a laser source.

  19. Complex network synchronization of chaotic systems with delay coupling

    SciTech Connect (OSTI)

    Theesar, S. Jeeva Sathya, E-mail: sjstheesar@gmail.com; Ratnavelu, K., E-mail: sjstheesar@gmail.com [Network Science Research Group, Institute of Mathematical Sciences, University of Malaya, 50603, Kuala Lumpur (Malaysia)

    2014-03-05T23:59:59.000Z

    The study of complex networks enables us to understand the collective behavior of the interconnected elements and provides vast real time applications from biology to laser dynamics. In this paper, synchronization of complex network of chaotic systems has been studied. Every identical node in the complex network is assumed to be in Lure system form. In particular, delayed coupling has been assumed along with identical sector bounded nonlinear systems which are interconnected over network topology.

  20. Digital-data receiver synchronization method and apparatus

    DOE Patents [OSTI]

    Smith, Stephen F. (Loudon, TN) [Loudon, TN; Turner, Gary W. (Clinton, TN) [Clinton, TN

    2009-09-08T23:59:59.000Z

    Digital data receiver synchronization is provided with composite phase-frequency detectors, mutually cross-connected comparison feedback or both to provide robust reception of digital data signals. A single master clock can be used to provide frequency signals. Advantages can include fast lock-up time in moderately to severely noisy conditions, greater tolerance to noise and jitter when locked, and improved tolerance to clock asymmetries.

  1. Digital-data receiver synchronization method and apparatus

    DOE Patents [OSTI]

    Smith, Stephen F.; Turner, Gary W.

    2005-12-06T23:59:59.000Z

    Digital-data receiver synchronization is provided with composite phase-frequency detectors, mutually cross-connected comparison feedback or both to provide robust reception of digital data signals. A single master clock may be used to provide frequency signals. Advantages can include fast lock-up time in moderately to severely noisy conditions, greater tolerance to noise and jitter when locked, and improved tolerance to clock asymmetries.

  2. Sensitivity of OFDM Systems to Synchronization Errors and Spatial Diversity

    E-Print Network [OSTI]

    Zhou, Yi

    2012-02-14T23:59:59.000Z

    of observations. Computer simulations show that the asymptotic bound is tight with more than 64 observations. Therefore, a good bench- mark for comparing the performance of different timing synchronizers is obtained. The selection of several system design.... 4. The curve marked with circles represents the actual ICI power from computer simulations while the curve with stars denotes the upper bound derived in (A.11). Fig. 4 illustrates that the derived upper bound predicts very accurately the ICI power...

  3. Generation of synchronized trains of picosecond laser pulses at two wavelengths in a single-cavity synchronously mode-locked dye laser

    E-Print Network [OSTI]

    Rocca, Jorge J.

    -cavity synchronously mode-locked dye laser 0. Buccafusca, J. J. Rocca, M. C. Marconi, and C. S. Menoni National Science-cavity synchronously pumped dye laser containing a mixture of two dyes in a single jet and intracavity spatial masking for frequency selection. The utilization of this dual wavelength dye laser to monitor the relaxation

  4. Copper laser modulator driving assembly including a magnetic compression laser

    DOE Patents [OSTI]

    Cook, Edward G. (Livermore, CA); Birx, Daniel L. (Oakley, CA); Ball, Don G. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    A laser modulator (10) having a low voltage assembly (12) with a plurality of low voltage modules (14) with first stage magnetic compression circuits (20) and magnetic assist inductors (28) with a common core (91), such that timing of the first stage magnetic switches (30b) is thereby synchronized. A bipolar second stage of magnetic compression (42) is coupled to the low voltage modules (14) through a bipolar pulse transformer (36) and a third stage of magnetic compression (44) is directly coupled to the second stage of magnetic compression (42). The low voltage assembly (12) includes pressurized boxes (117) for improving voltage standoff between the primary winding assemblies (34) and secondary winding (40) contained therein.

  5. Magnet Coil Shorted Turn Detector

    SciTech Connect (OSTI)

    Dinkel, J.A.; Biggs, J.E.

    1994-03-01T23:59:59.000Z

    The Magnet Coil Shorted Turn Detector has been developed to facilitate the location of shorted turns in magnet coils. Finding these shorted turns is necessary to determine failure modes that are a necessary step in developing future production techniques. Up to this point, coils with shorted turns had the insulation burned off without the fault having been located. This disassembly process destroyed any chance of being able to find the fault. In order to maintain a flux balance in a coupled system such as a magnet coil, the current in a shorted turn must be opposed to the incident current. If the direction of the current in each conductor can be measured relative to the incident current, then the exact location of the short can be determined. In this device, an AC voltage is applied to the magnet under test. A small hand held B-dot pickup coil monitors the magnetic field produced by current in the individual magnet conductors. The relative phase of this pickup coil voltage is compared to a reference signal derived from the input current to detect a current reversal as the B-dot pickup coil is swept over the conductors of the coil under test. This technique however, is limited to only those conductors that are accessible to the hand held probe.

  6. 2528 IEEE TRANSACTIONS ON MAGNETICS, VOL. 43, NO. 6, JUNE 2007 A Highly Efficient 200 000 RPM Permanent Magnet Motor System

    E-Print Network [OSTI]

    Wu, Thomas

    presents the development of an ultra-high-speed permanent magnet synchronous motor (PMSM) that produces large iron loss at high-speed. In ultra-high-speed applications, PMSM offers the advantage of high efficiency, and high stability, is generally considered for high performance PMSM control. However, for ultra

  7. Sublattice Magnetic Relaxation in Rare Earth Iron Garnets

    SciTech Connect (OSTI)

    McCloy, John S.; Walsh, Brian

    2013-07-08T23:59:59.000Z

    The magnetic properties of rare earth garnets make them attractive materials for applications ranging from optical communications to magnetic refrigeration. The purpose of this research was to determine the AC magnetic properties of several rare earth garnets, in order to ascertain the contributions of various sublattices. Gd3Fe5O12, Gd3Ga5O12, Tb3Fe5O12, Tb3Ga5O12, and Y3Fe5O12 were synthesized by a solid state reaction of their oxides and verified by x-ray diffraction. Frequency-dependent AC susceptibility and DC magnetization were measured versus temperature (10 340 K). Field cooling had little effect on AC susceptibility, but large effect on DC magnetization, increasing magnetization at the lowest temperature and shifting the compensation point to lower temperatures. Data suggest that interaction of the two iron lattices results in the two frequency dependent magnetic relaxations in the iron garnets, which were fit using the Vogel-Fulcher and Arrhenius laws.

  8. Cell body rocking is a dominant mechanism for flagellar synchronization in a swimming algae

    E-Print Network [OSTI]

    Geyer, Veikko; Howard, Jonathon; Friedrich, Benjamin M

    2013-01-01T23:59:59.000Z

    The unicellular green algae Chlamydomonas swims with two flagella, which can synchronize their beat. Synchronized beating is required to swim both fast and straight. A long-standing hypothesis proposes that synchronization of flagella results from hydrodynamic coupling, but the details are not understood. Here, we present realistic hydrodynamic computations and high-speed tracking experiments of swimming cells that show how a perturbation from the synchronized state causes rotational motion of the cell body. This rotation feeds back on the flagellar dynamics via hydrodynamic friction forces and rapidly restores the synchronized state in our theory. We calculate that this `cell body rocking' provides the dominant contribution to synchronization in swimming cells, whereas direct hydrodynamic interactions between the flagella contribute negligibly. We experimentally confirmed the coupling between flagellar beating and cell body rocking predicted by our theory. We propose that the interplay of flagellar beating a...

  9. On obliquely magnetized and differentially rotating stars

    E-Print Network [OSTI]

    Wei, Xing

    2015-01-01T23:59:59.000Z

    We investigate the interaction of differential rotation and a misaligned magnetic field. The incompressible magnetohydrodynamic equations are solved numerically for a free-decay problem. In the kinematic limit, differential rotation annihilates the non-axisymmetric field on a timescale proportional to the cube root of magnetic Reynolds number ($Rm$), as predicted by R\\"adler. Nonlinearly, the outcome depends upon the initial energy in the non-axisymmetric part of the field. Sufficiently weak fields approach axisymmetry as in the kinematic limit; some differential rotation survives across magnetic surfaces, at least on intermediate timescales. Stronger fields enforce uniform rotation and remain non-axisymmetric. The initial field strength that divides these two regimes does not follow the scaling $Rm^{-1/3}$ predicted by quasi-kinematic arguments, perhaps because our $Rm$ is never sufficiently large or because of reconnection. We discuss the possible relevance of these results to tidal synchronization and tida...

  10. arXiv:1103.2923v1[math.OC]15Mar2011 Estimation of Saturation of Permanent-Magnet

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    a parametric model of the saturated Permanent-Magnet Synchronous Motor (PMSM) together with an estimation on a surface-mounted PMSM and an interoir magnet PMSM illustrate the relevance of the approach. Index Terms (PMSM) at low velocity remains a challenging task. Most of the existing control algorithms rely

  11. The Optimal Power Tracking Control Strategy of Grid-Connected Excited Synchronous Wind Power Generator.

    E-Print Network [OSTI]

    Cheng, Wen-kai

    2014-01-01T23:59:59.000Z

    ??In this thesis, the wind power system is a coaxial coupling structure between servo motor and excited synchronous wind power generator. By using the excited (more)

  12. E-Print Network 3.0 - axial-gap type synchronous Sample Search...

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

    of Electrical and Computer Engineering, University of Tennessee Collection: Engineering 2 Ad Hoc Synchronization Considered Harmful Weiwei Xiong+, Soyeon Park, Jiaqi Zhang,...

  13. E-Print Network 3.0 - asynchronous inhibition-mediated synchronization...

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

    modification to the current synchronization algorithm... for the asynchronism problem. Section 7 concludes the paper. ... Source: Lai, Ten-Hwang "Steve" - Department of Computer...

  14. Solid State AC Motor Drives - Conservation Perspectives

    E-Print Network [OSTI]

    Mohan, N.; Ferraro, R. J.

    1982-01-01T23:59:59.000Z

    This paper presents and discusses techniques for energy conservation by reducing losses in ac motor driven systems, proposed by the technical community in response to surging cost of energy. An important aspect considered is the impact on electric...

  15. Determination of ovulation time in the superovulated and synchronized bovine

    E-Print Network [OSTI]

    Maxwell, Duane Paul

    1977-01-01T23:59:59.000Z

    &VTS INTRODUCTION LITERATURE REVIEW Time or Ovulation Superovulation with Pregnant 3Iare Soru&a Gonadot rop in Synchronization with Prosta?lan&lins Superovulation and Synchronizat. i. on Using PMSG and PGFzn I. aparoscopy Nonsurgical Ova Collection Plasma..."). {b) When &. ows with functional corpora lu ea arc superovulated and insea&inated, th&. ova are not fert) li. zed (Cas)da et al. , 1943; Rowson, 195l. ; IVillett et al , 1952) . (cj I xcessivc d&'scs of gonadotropins are counter-n reductive...

  16. On chip clock synchronization for large digital systems

    E-Print Network [OSTI]

    Brueske, Daniel

    1994-01-01T23:59:59.000Z

    . Figure 4. Figure 5. Data Synchronization. Simple Inverter and Dynamic Power Dissipation. Single Wire Clock Network. H ? Tree Clock Distribution Network. Balanced Clock Tree al'ter [8]. Figurc 6. PLL Based Distributed System. Figurc 7. Phase Lock... is distributed to the various elements using such an architecture. This type of network has been successfully used in the Alpha chip [3]. A large buffer is used to drive a single wire laid across the chip. Several of the buffer ? wire are connected in Vin 1...

  17. Global synchronization of parallel processors using clock pulse width modulation

    DOE Patents [OSTI]

    Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

    2013-04-02T23:59:59.000Z

    A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

  18. Synchronization of multimedia streams over packet-switched networks

    E-Print Network [OSTI]

    Brewer, Jason M.

    1995-01-01T23:59:59.000Z

    -TIME MULTIMEDIA NETWORK AP- PLICATIONS A. Compression . 1. Audio Compression 2. Video Compression B. Sources of Variable Delay . 1. Coding Delays 2. Network Jitter 3. Sum Effects of Delays C. QoS and Network Protocols 1. Quality of Service (Qo... header fields 45 21 Temporal distortion caused by delay adjustment during a talkspurt. . 46 22 End-to-end steps for a video frame 48 23 End-to-end steps for an audio segment. 24 Synchronization Algorithm. 51 25 26 27 28 Original end-to-end delay...

  19. Synchronization and Collective Dynamics in a Carpet of Microfluidic Rotors

    E-Print Network [OSTI]

    Nariya Uchida; Ramin Golestanian

    2010-04-28T23:59:59.000Z

    We study synchronization of an array of rotors on a substrate that are coupled by hydrodynamic interaction. The rotors that are modeled by an effective rigid body, are driven by an internal torque and exerts an active force on the surrounding fluid. The long-ranged nature of the hydrodynamic interaction between the rotors causes a rich pattern of dynamical behaviors including phase ordering and turbulent spiral waves. The model provides a novel example of coupled oscillators with long-range interaction. Our results suggest strategies for designing controllable microfluidic mixers using the emergent behavior of hydrodynamically coupled active components.

  20. EP-MAC e-mail : jyoak@snu.ac.kr, sbahk@snu.ac.kr

    E-Print Network [OSTI]

    Bahk, Saewoong

    EP-MAC *, e-mail : jyoak@snu.ac.kr, sbahk@snu.ac.kr Early Preamble MAC to reduce-cycled wireless sensor motes. In this paper we propose Early Preamble-MAC(EP-MAC) which enables to get enhanced performance of low energy and low latency. EP-MAC uses both early preamble and original simple preamble, so

  1. Geothermal heating enhances atmospheric asymmetries on synchronously rotating planets

    E-Print Network [OSTI]

    Haqq-Misra, Jacob

    2014-01-01T23:59:59.000Z

    Earth-like planets within the liquid water habitable zone of M type stars may evolve into synchronous rotators. On these planets, the sub-stellar hemisphere experiences perpetual daylight while the opposing anti-stellar hemisphere experiences perpetual darkness. Because the night-side hemisphere has no direct source of energy, the air over this side of the planet is prone to freeze out and deposit on the surface, which could result in atmospheric collapse. However, general circulation models (GCMs) have shown that atmospheric dynamics can counteract this problem and provide sufficient energy transport to the anti-stellar side. Here we use an idealized GCM to consider the impact of geothermal heating on the habitability of synchronously rotating planets. Geothermal heating may be expected due to tidal interactions with the host star, and the effects of geothermal heating provide additional habitable surface area and may help to induce melting of ice on the anti-stellar hemisphere. We also explore the persisten...

  2. Spontaneous synchronization driven by energy transport in interconnected networks

    E-Print Network [OSTI]

    Vincenzo Nicosia; Per Sebastian Skardal; Vito Latora; Alex Arenas

    2014-07-22T23:59:59.000Z

    Understanding dynamical processes on networks is an important area of research in complex systems, with far reaching implications and applications in many real-world cases. However, the research to date has mainly focused on single dynamical processes occurring on isolated networks, and very little is known about the more interesting and realistic case of different kinds of intertwined dynamical processes taking place on interconnected networks. An example of the non-trivial combination of two types of dynamics can be found in the human brain, where cerebral circulation delivers the nutrients and oxygenated blood needed for the activity of the different brain areas, and in turn the activity of a region can induce changes in the distribution of blood flow. Here, we introduce and study a model of intertwined dynamics on interconnected networks, inspired by the human brain, which consists of bidirectionally coupled synchronization and energy transport processes. Remarkably, the proposed model allows the emergence of spontaneous switch-like synchronization transitions driven by the energy transport dynamics, which qualitatively mirror the transitions observed in human brain dynamics between resting-state and cognitive activity. We provide a steady-state analytical explanation for the observed behavior and furthermore show that the switch-like transition is robust over a wide range of model parameters and network topologies. We suggest that the complexity inherent in other interconnected dynamical processes might be responsible for various other emergent behaviors observed in natural systems.

  3. Three phase AC motor controller

    DOE Patents [OSTI]

    Vuckovich, Michael (Elizabeth, PA); Wright, Maynard K. (Bethel Park, PA); Burkett, John P. (South Huntington Township, Westmoreland County, PA)

    1984-03-20T23:59:59.000Z

    A motor controller for a three phase AC motor (10) which is adapted to operate bidirectionally from signals received either from a computer (30) or a manual control (32). The controller is comprised of digital logic circuit means which implement a forward and reverse command signal channel (27, 29) for the application of power through the forward and reverse power switching relays (16, 18, 20, 22). The digital logic elements are cross coupled to prevent activation of both channels simultaneously and each includes a plugging circuit (65, 67) for stopping the motor upon the removal of control signal applied to one of the two channels (27, 29) for a direction of rotation desired. Each plugging circuit (65, 67) includes a one-shot pulse signal generator (88, 102) which outputs a single pulse signal of predetermined pulsewidth which is adapted to inhibit further operation of the application of power in the channel which is being activated and to apply a reversal command signal to the other channel which provides a reversed phase application of power to the motor for a period defined by the pulse-width output of the one-shot signal generator to plug the motor (10) which will then be inoperative until another rotational command signal is applied to either of the two channels.

  4. Co-Simulation of an Interior Permanent Magnet Synchronous Motor with Segmented Rotor Structure

    E-Print Network [OSTI]

    Paderborn, Universität

    Christoph Schulte and Joachim B¨ocker Power Electronics and Electrical Drives, Paderborn University, D-33095 Paderborn, Germany schulte@lea.upb.de, boecker@lea.upb.de Abstract--Accurate simulation of electric drives, electrical drive, multi-slice approach I. INTRODUCTION Conventionally, a two-step process is being used

  5. Sensorless Speed Control of Permanent Magnet-Assisted Synchronous Reluctance Motor (PMa-SynRM)

    E-Print Network [OSTI]

    Chakali, Anil K.

    2011-02-22T23:59:59.000Z

    Page 5-17 (From top to bottom) Phase A current (DSP)-[1V/div], q-axis and d-axis currents-[1V/div] when motor speed is changed from 130RPM to 10RPM and back to 130RPM... torque at standstill (i.e., zero speed) and low speeds as well as constant output power over wide speed range. In order to meet these requirements, the PMa-SynRM machines are designed to operate not only in the constant torque region where the motor...

  6. Direct - drive permanent magnet synchronous generator design for hydrokinetic energy extraction .

    E-Print Network [OSTI]

    Kashyap, Amshumaan Raghunatha

    2013-01-01T23:59:59.000Z

    ??"Hydrokinetic turbines deliver lower shaft speeds when compared to both steam and wind turbines. Hence, a water wheel generator must operate at speeds as low (more)

  7. Monitoring Critical Temperatures in Permanent Magnet Synchronous Motors Using Low-Order

    E-Print Network [OSTI]

    Paderborn, Universität

    systems. The model performances are validated by extensive experimental results based on a high-speed PMSM

  8. A Comparative Study of Two Predictive Current Controls for a Permanent Magnet Synchronous

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Machines (PMSM) drives. The first tested control scheme is based on a model including the inverter and the PMSM and taking into account the discrete nature of the inverter leg states. It predicts the future time. The second tested control scheme uses a model of the PMSM to predict the output voltages which

  9. Direct Torque Control for Interior Permanent Magnet Synchronous Motors with Respect to Optimal Efficiency

    E-Print Network [OSTI]

    Paderborn, Universität

    motors (PMSM) increased significantly. Thus, this motor type becomes more and more attractive for drive-axis current of the motor must not be controlled to zero, as it is common with non-salient PMSM. Thus

  10. Noise reduction control strategy of a permanent magnet synchronous machine for vehicle applications

    E-Print Network [OSTI]

    Doolittle, Randy Gene

    2009-05-15T23:59:59.000Z

    Figure 2.1 Single Pole of a Ten Pole PMSM Similar to the Investigated Machine............................................................................................. 13 Figure 2.2 Use of Available Parameters to Build a Triangle Based... prevalence of the PMSM as the machine of choice for traction motor applications, the author chose to research a topic which concentrated on this machine and its corresponding ASD platform. Through previous coursework, the author has learned...

  11. Dynamic environment coupling induce synchronized states in coupled time-delayed electronic circuits

    E-Print Network [OSTI]

    R. Suresh; K. Srinivasan; D. V. Senthilkumar; K. Murali; M. Lakshmanan; J. Kurths

    2014-01-27T23:59:59.000Z

    We experimentally demonstrate the occurrence of various synchronized states in coupled piece-wise linear time-delayed electronic circuits using dynamic environment coupling where the environment has its own intrinsic dynamics via feedback from the circuits. We carry out these experiments in two different coupling configurations, namely mutual and subsystem coupling configurations. Depending upon the coupling strength and the nature of feedback, we observe a transition from nonsynchronization to complete synchronization via phase synchronization and from nonsynchronization to inverse synchronization via inverse-phase synchronization between the circuits in hyperchaotic regime. Snapshots of the time evolution, phase projection plots and localized sets of the circuits as observed experimentally from the oscilloscope, along with supporting numerical simulations confirm the existence of different synchronized states. Further, the transition to different synchronized states can be verified from the changes in the largest Lyapunov exponents, Correlation of Probability of Recurrence and Correlation Coefficient as a function of the coupling strength. We present a detailed linear stability analysis and obtain conditions for different synchronized states.

  12. High intensity picosecond Fourier limited pulses : design of a synchronously pumped dye laser system

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    527 High intensity picosecond Fourier limited pulses : design of a synchronously pumped dye laser picosecond pulses. A Nd : Yag picosecond laser is used to synchronously pump a dye oscillator/amplifier system. The dye oscillator is of the Littman type. Up to 1.5 mJ of energy is obtained in a 20 ps pulse

  13. Globally synchronous ice core volcanic tracers and abrupt cooling during the last glacial period

    E-Print Network [OSTI]

    Price, P. Buford

    Globally synchronous ice core volcanic tracers and abrupt cooling during the last glacial period R (2006), Globally synchronous ice core volcanic tracers and abrupt cooling during the last glacial period histories from ice coring of Greenland and Antarctica over the period 2 to 45 ka, using SO4 anomalies

  14. Spatially Synchronous Extinction of Species under External Forcing R. E. Amritkar*

    E-Print Network [OSTI]

    Rangarajan, Govindan

    Spatially Synchronous Extinction of Species under External Forcing R. E. Amritkar* Physical a synchronizing term. Absence of the quadratic saturation term can help the species to avoid extinction. DOI: 10 other examples are documented in Ref. [10]. The second important phenomenon is the extinction of species

  15. SYNCHRONIZATION OF PRESENTATION SLIDES AND LECTURE VIDEOS USING BIT RATE SEQUENCES

    E-Print Network [OSTI]

    Girod, Bernd

    SYNCHRONIZATION OF PRESENTATION SLIDES AND LECTURE VIDEOS USING BIT RATE SEQUENCES G. Schroth1 , N The temporal synchronization of presentation slides and lecture videos enables us to enhance the user and reliably detect and recognize slide changes, which is based on bit rate sequences. By exploiting readily

  16. Optimum Frame Synchronization for Preamble-less Packet Transmission of Turbo Codes

    E-Print Network [OSTI]

    Valenti, Matthew C.

    Optimum Frame Synchronization for Preamble-less Packet Transmission of Turbo Codes Jian Sun introduces an optimum maximum a posteriori (MAP) frame synchronization method for packet- based turbo coded the received signal sequences. This method is based on the low- density parity-check properties of turbo codes

  17. On Improving the Intelligibility of Synchronized Over-lap-and-Add (SOLA) at Low TSM Factor

    E-Print Network [OSTI]

    Wong, Peter Hon-Wah

    On Improving the Intelligibility of Synchronized Over- lap-and-Add (SOLA) at Low TSM Factor Peter H-7053** ABSTRACT In this paper, we propose an algorithm to modify the Synchronized Overlap-and-Add (SOLA) technique. SOLA is a popular technique for time scale modification of speech and audio signal. It changes the time

  18. Compositionality in Synchronous Data Flow: Modular Code Generation from Hierarchical SDF Graphs

    E-Print Network [OSTI]

    Compositionality in Synchronous Data Flow: Modular Code Generation from Hierarchical SDF Graphs in Synchronous Data Flow: Modular Code Generation from Hierarchical SDF Graphs Stavros Tripakis, Dai Bui, Bert of California, Berkeley stavros, daib, eal@eecs.berkeley.edu October 20, 2009 Abstract Hierarchical SDF models

  19. Cosimulating Synchronous DSP Applications with Analog RF Circuits Jos Luis Pino and Khalil Kalbasi

    E-Print Network [OSTI]

    , synchronous dataflow (SDF), SPICE and circuit envelope simulation technologies are reviewed. Each. There are several forms of dataflow defined in HP Ptolemy. Synchronous dataflow(SDF), allows the succinct rates in the system are rationally related. SDF is ideally suited to a large set of DSP applications

  20. Synchronization-Free Parallel Collision Detection Pipeline Quentin Avril Valerie Gouranton Bruno Arnaldi

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Synchronization-Free Parallel Collision Detection Pipeline Quentin Avril Val´erie Gouranton Bruno a first parallel and adaptive collision detection pipeline running on a multi-core architecture. This pipeline integrates a first global synchronization-free parallelization of its major steps and enables

  1. SYNCHRONIZATION OF COMBUSTION VARIATIONS IN A MULTI-CYLINDER SPARK IGNITION ENGINE

    E-Print Network [OSTI]

    Tennessee, University of

    SYNCHRONIZATION OF COMBUSTION VARIATIONS IN A MULTI-CYLINDER SPARK IGNITION ENGINE C. Stuart Daw combustion variations in dif- ferent cylinders at fuel-lean conditions in an eight-cylinder spark ignition of synchronization is associated with bifurca- tion instabilities reported previously for combustion in single

  2. A synchronous model of the PLC programming language ST Fernando Jimenez-Fraustro

    E-Print Network [OSTI]

    Boyer, Edmond

    A synchronous model of the PLC programming language ST Fernando Jimenez-Fraustro IRISA / INRIA F of a synchronous model of the PLC programming lan- guage ST. This work is part of the integration of the IEC 1131 Logic Controllers (PLC) architec- tures. Their design relies on standards like the IEC 1131 norm

  3. On the Scalability of Data Synchronization Protocols for PDAs and Mobile Devices

    E-Print Network [OSTI]

    Goldberg, Bennett

    Boston University Abstract Personal Digital Assistants (PDAs) and other mobile computing devices relyOn the Scalability of Data Synchronization Protocols for PDAs and Mobile Devices S. Agarwal D, tetherless networks. Keywords: Personal Digital Assistants, mobile networks, data synchronization A version

  4. Magnetic investigations

    SciTech Connect (OSTI)

    Bath, G.D.; Jahren, C.E.; Rosenbaum, J.G. [Geological Survey, Denver, CO (USA); Baldwin, M.J. [Fenix and Scisson, Inc., Mercury, NV (USA)

    1983-12-31T23:59:59.000Z

    Air and ground magnetic anomalies in the Climax stock area of the NTS help define the gross configuration of the stock and detailed configuration of magnetized rocks at the Boundary and Tippinip faults that border the stock. Magnetizations of geologic units were evaluated by measurements of magnetic properties of drill core, minimum estimates of magnetizations from ground magnetic anomalies for near surface rocks, and comparisons of measured anomalies with anomalies computed by a three-dimensional forward program. Alluvial deposits and most sedimentary rocks are nonmagnetic, but drill core measurements reveal large and irregular changes in magnetization for some quartzites and marbles. The magnetizations of quartz monzonite and granodiorite near the stock surface are weak, about 0.15 A/m, and increase at a rate of 0.00196 A/m/m to 1.55 A/m, at depths greater than 700 m (2300 ft). The volcanic rocks of the area are weakly magnetized. Aeromagnetic anomalies 850 m (2800 ft) above the stock are explained by a model consisting of five vertical prisms. Prisms 1, 2, and 3 represent the near surface outline of the stock, prism 4 is one of the models developed by Whitehill (1973), and prism 5 is modified from the model developed by Allingham and Zietz (1962). Most of the anomaly comes from unsampled and strongly-magnetized deep sources that could be either granite or metamorphosed sedimentary rocks. 48 refs., 23 figs., 3 tabs.

  5. Advanced Technology Vehicle Lab Benchmarking - Level 2 (in-depth...

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

    Gasoline Engine - 1.8 liters Atkinson cycle engine, 98 hp@5200 Electric Motors - Permanent magnet AC synchronous motors - Traction motor: 60 kW, 207 Nm - Generator: 41 kW, 40...

  6. Synchronized states in chaotic systems coupled indirectly through a dynamic environment

    E-Print Network [OSTI]

    V. Resmi; G. Ambika; R. E. Amritkar

    2010-05-04T23:59:59.000Z

    We consider synchronization of chaotic systems coupled indirectly through a common environmnet where the environment has an intrinsic dynmics of its own modulated via feedback from the systems. We find that a rich vareity of synchronization behavior, such as in-phase, anti-phase,complete and anti- synchronization is possible. We present an approximate stability analysis for the different synchronization behaviors. The transitions to different states of synchronous behaviour are analyzed in the parameter plane of coupling strengths by numerical studies for specific cases such as Rossler and Lorenz systems and are characterized using various indices such as correlation, average phase difference and Lyapunov exponents. The threshold condition obtained from numerical analysis is found to agree with that from the stability analysis.

  7. Elastic ice shells of synchronous moons: Implications for cracks on Europa and non-synchronous rotation of Titan

    E-Print Network [OSTI]

    Goldreich, Peter M

    2009-01-01T23:59:59.000Z

    A number of synchronous moons are thought to harbor water oceans beneath their outer ice shells. A subsurface ocean frictionally decouples the shell from the interior. This decoupling has led to proposals that a weak tidal or atmospheric torque might cause the shell to rotate differentially with respect to the synchronously rotating interior. Applications along these lines have been made to Europa and Titan. As a result of centrifugal and tidal forces, the oceans of Europa and Titan have ellipsoidal figures whose long axes point toward the parent planet. Any rotation of the shell away from its equilibrium position induces strains thereby increasing its elastic energy. Thus the shell is coupled to the ocean by an elastic torque. Regarding Europa, it is shown that the tidal torque is far too weak to produce stresses that could fracture the ice shell, thus refuting an idea that has been widely advocated. An alternative formation mechanism for large cracks is proposed. Two years of Cassini RADAR observations of T...

  8. Strange Magnetism

    E-Print Network [OSTI]

    Thomas R. Hemmert; Ulf-G. Meissner; Sven Steininger

    1998-11-09T23:59:59.000Z

    We present an analytic and parameter-free expression for the momentum dependence of the strange magnetic form factor of the nucleon and its corresponding radius which has been derived in Heavy Baryon Chiral Perturbation Theory. We also discuss a model-independent relation between the isoscalar magnetic and the strange magnetic form factors of the nucleon based on chiral symmetry and SU(3) only. These limites are used to derive bounds on the strange magnetic moment of the proton from the recent measurement by the SAMPLE collaboration.

  9. Magnetic Field Safety Magnetic Field Safety

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Magnetic Field Safety Training #12;Magnetic Field Safety Strong Magnetic Fields exist around energized magnets. High magnetic fields alone are a recognized hazard only for personnel with certain medical conditions such as pacemakers, magnetic implants, or embedded shrapnel. In addition, high magnetic

  10. Cinema 16 Collection / A.C. Killip (collector)

    E-Print Network [OSTI]

    Handy, Todd C.

    Cinema 16 Collection / A.C. Killip (collector) University of British Columbia Archives #12;Table;Collection Description Cinema 16 Collection / A.C. Killip (collector). 1961-1970. 1.5 cm of textual records

  11. Synchronizing compute node time bases in a parallel computer

    DOE Patents [OSTI]

    Chen, Dong; Faraj, Daniel A; Gooding, Thomas M; Heidelberger, Philip

    2014-12-30T23:59:59.000Z

    Synchronizing time bases in a parallel computer that includes compute nodes organized for data communications in a tree network, where one compute node is designated as a root, and, for each compute node: calculating data transmission latency from the root to the compute node; configuring a thread as a pulse waiter; initializing a wakeup unit; and performing a local barrier operation; upon each node completing the local barrier operation, entering, by all compute nodes, a global barrier operation; upon all nodes entering the global barrier operation, sending, to all the compute nodes, a pulse signal; and for each compute node upon receiving the pulse signal: waking, by the wakeup unit, the pulse waiter; setting a time base for the compute node equal to the data transmission latency between the root node and the compute node; and exiting the global barrier operation.

  12. An Expectation-Maximization Method for Calibrating Synchronous Machine Models

    SciTech Connect (OSTI)

    Meng, Da; Zhou, Ning; Lu, Shuai; Lin, Guang

    2013-07-21T23:59:59.000Z

    The accuracy of a power system dynamic model is essential to its secure and efficient operation. Lower confidence in model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, this paper proposes an expectation-maximization (EM) method to calibrate the synchronous machine model using phasor measurement unit (PMU) data. First, an extended Kalman filter (EKF) is applied to estimate the dynamic states using measurement data. Then, the parameters are calculated based on the estimated states using maximum likelihood estimation (MLE) method. The EM method iterates over the preceding two steps to improve estimation accuracy. The proposed EM methods performance is evaluated using a single-machine infinite bus system and compared with a method where both state and parameters are estimated using an EKF method. Sensitivity studies of the parameter calibration using EM method are also presented to show the robustness of the proposed method for different levels of measurement noise and initial parameter uncertainty.

  13. www.mmu.ac.uk/careers Careers & Employability Service

    E-Print Network [OSTI]

    .mmu.ac.uk/careers Identifying courses · www.prospects.ac.uk/search_courses.htm · www.jobs.ac.uk · www.Findamasters.com · www.mmu.ac.uk/careers PG Professional/Vocational courses: Courses to allow you to enter certain professions Courses involve lectures for the first two terms then a research project for the final term (often finishing after

  14. The Helioseismic and Magnetic Imager (HMI) Vector Magnetic Field Pipeline: Magnetohydrodynamics Simulation Module for the Global Solar Corona

    E-Print Network [OSTI]

    Hayashi, Keiji; Liu, Yang; Bobra, Monica G; Sun, Xudong D; Norton, Aimee A

    2015-01-01T23:59:59.000Z

    Time-dependent three-dimensional magnetohydrodynamics (MHD) simulation modules are implemented at the Joint Science Operation Center (JSOC) of Solar Dynamics Observatory (SDO). The modules regularly produce three-dimensional data of the time-relaxed minimum-energy state of the solar corona using global solar-surface magnetic-field maps created from Helioseismic Magnetic Imager (HMI) full-disk magnetogram data. With the assumption of polytropic gas with specific heat ratio of 1.05, three types of simulation products are currently generated: i) simulation data with medium spatial resolution using the definitive calibrated synoptic map of the magnetic field with a cadence of one Carrington rotation, ii) data with low spatial resolution using the definitive version of the synchronic frame format of the magnetic field, with a cadence of one day, and iii) low-resolution data using near-real-time (NRT) synchronic format of the magnetic field on daily basis. The MHD data available in the JSOC database are three-dimen...

  15. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, J.A.; Stone, R.R.; Fabyan, J.

    1985-02-12T23:59:59.000Z

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

  16. 16,000-rpm Interior Permanent Magnet Reluctance Machine with Brushless Field Excitation

    SciTech Connect (OSTI)

    Hsu, J.S.; Burress, T.A.; Lee, S.T.; Wiles, R.H.; Coomer, C.L.; McKeever, J.W.; Adams, D.J.

    2007-10-31T23:59:59.000Z

    The reluctance interior permanent magnet (RIPM) motor is currently used by many leading auto manufacturers for hybrid vehicles. The power density for this type of motor is high compared with that of induction motors and switched reluctance motors. The primary drawback of the RIPM motor is the permanent magnet (PM) because during high-speed operation, the fixed PM produces a huge back electromotive force (emf) that must be reduced before the current will pass through the stator windings. This reduction in back-emf is accomplished with a significant direct-axis (d-axis) demagnetization current, which opposes the PM's flux to reduce the flux seen by the stator wires. This may lower the power factor and efficiency of the motor and raise the requirement on the alternate current (ac) power supply; consequently, bigger inverter switching components, thicker motor winding conductors, and heavier cables are required. The direct current (dc) link capacitor is also affected when it must accommodate heavier harmonic currents. It is commonly agreed that, for synchronous machines, the power factor can be optimized by varying the field excitation to minimize the current. The field produced by the PM is fixed and cannot be adjusted. What can be adjusted is reactive current to the d-axis of the stator winding, which consumes reactive power but does not always help to improve the power factor. The objective of this project is to avoid the primary drawbacks of the RIPM motor by introducing brushless field excitation (BFE). This offers both high torque per ampere (A) per core length at low speed by using flux, which is enhanced by increasing current to a fixed excitation coil, and flux, which is weakened at high speed by reducing current to the excitation coil. If field weakening is used, the dc/dc boost converter used in a conventional RIPM motor may be eliminated to reduce system costs. However, BFE supports a drive system with a dc/dc boost converter, because it can further extend the constant power speed range of the drive system and adjust the field for power factor and efficiency gains. Lower core losses at low torque regions, especially at high speeds, are attained by reducing the field excitation. Safety and reliability are increased by weakening the field when a winding short-circuit fault occurs, preventing damage to the motor. For a high-speed motor operating at 16,000-revolutions per minute (rpm), mechanical stress is a challenge. Bridges that link the rotor punching segments together must be thickened for mechanical integrity; consequently, increased rotor flux leakage significantly lowers motor performance. This barrier can be overcome by BFE to ensure sufficient rotor flux when needed.

  17. www.strath.ac.uk THIS IS YOUR

    E-Print Network [OSTI]

    Mottram, Nigel

    Building Lorna Bennet SBS Exchange Co-ordinator Michele French SBS Exchange Secretary 01 | Contents 03 Building erkan.oterkus@strath.ac.uk Lorna Bennet Strathclyde Business School Level 2, Sir William Duncan Building lorna.bennet@strath.ac.uk www.strath.ac.uk | 06 #12;Key Dates www

  18. STATE OF CALIFORNIA DISTRIBUTED ENERGY STORAGE DX AC SYSTEMES ACCEPTANCE

    E-Print Network [OSTI]

    STATE OF CALIFORNIA DISTRIBUTED ENERGY STORAGE DX AC SYSTEMES ACCEPTANCE CEC-MECH-14A (Revised 08/09) CALIFORNIA ENERGY COMMISSION CERTIFICATE OF ACCEPTANCE MECH-14A NA7.5.13 Distributed Energy Storage DX AC DISTRIBUTED ENERGY STORAGE DX AC SYSTEMES ACCEPTANCE CEC-MECH-14A (Revised 08/09) CALIFORNIA ENERGY COMMISSION

  19. www.pet.hw.ac.uk 1 Private and Confidential

    E-Print Network [OSTI]

    Painter, Kevin

    www.pet.hw.ac.uk 1 Private and Confidential Application for MSc Courses - Supplementary Information of Exam Grade Attained Subjects taken at `O' level or equivalent with grades #12;www.pet.hw.ac.uk 2 of principal & subsidiary subjects Please leave blank for Institute Use #12;www.pet.hw.ac.uk 3 Employment Dates

  20. EXPERIMENTAL STUDY OF ELECTROLYTE DEPENDENCE OF AC ELECTROOSMOTIC PUMPS

    E-Print Network [OSTI]

    Bazant, Martin Z.

    EXPERIMENTAL STUDY OF ELECTROLYTE DEPENDENCE OF AC ELECTROOSMOTIC PUMPS Kapil Subramanian1 , John Abstract: Recent studies indicate increased efficiency of microfluidic ac electro-osmotic pumps of ac electroosmosis in microchannels on solution chemistry for the new fast aceo stepped pumps

  1. Magnetic nanotubes

    DOE Patents [OSTI]

    Matsui, Hiroshi (Glen Rock, NJ); Matsunaga, Tadashi (Tokyo, JP)

    2010-11-16T23:59:59.000Z

    A magnetic nanotube includes bacterial magnetic nanocrystals contacted onto a nanotube which absorbs the nanocrystals. The nanocrystals are contacted on at least one surface of the nanotube. A method of fabricating a magnetic nanotube includes synthesizing the bacterial magnetic nanocrystals, which have an outer layer of proteins. A nanotube provided is capable of absorbing the nanocrystals and contacting the nanotube with the nanocrystals. The nanotube is preferably a peptide bolaamphiphile. A nanotube solution and a nanocrystal solution including a buffer and a concentration of nanocrystals are mixed. The concentration of nanocrystals is optimized, resulting in a nanocrystal to nanotube ratio for which bacterial magnetic nanocrystals are immobilized on at least one surface of the nanotubes. The ratio controls whether the nanocrystals bind only to the interior or to the exterior surfaces of the nanotubes. Uses include cell manipulation and separation, biological assay, enzyme recovery, and biosensors.

  2. Synchronization in hyperchaotic time-delayed electronic oscillators coupled indirectly via a common environment

    E-Print Network [OSTI]

    Tanmoy Banerjee; Debabrata Biswas

    2013-03-21T23:59:59.000Z

    The present paper explores the synchronization scenario of hyperchaotic time-delayed electronic oscillators coupled indirectly via a common environment. We show that depending upon the coupling parameters a hyperchaotic time-delayed system can show in-phase or complete synchronization, and also inverse-phase or anti-synchronization. This paper reports the first experimental confirmation of synchronization of hyperchaos in time-delayed electronic oscillators coupled indirectly through a common environment. We confirm the occurrence of in-phase and inverse-phase synchronization phenomena in the coupled system through the dynamical measures like generalized autocorrelation function, correlation of probability of recurrence, and the concept of localized sets computed directly from the experimental time-series data. We also present a linear stability analysis of the coupled system. The experimental and analytical results are further supported by the detailed numerical analysis of the coupled system. Apart from the above mentioned measures, we numerically compute another quantitative measure, namely, Lyapunov exponent spectrum of the coupled system that confirms the transition from the in-phase (inverse-phase) synchronized state to the complete (anti-) synchronized state with the increasing coupling strength.

  3. Generation-based memory synchronization in a multiprocessor system with weakly consistent memory accesses

    DOE Patents [OSTI]

    Ohmacht, Martin

    2014-09-09T23:59:59.000Z

    In a multiprocessor system, a central memory synchronization module coordinates memory synchronization requests responsive to memory access requests in flight, a generation counter, and a reclaim pointer. The central module communicates via point-to-point communication. The module includes a global OR reduce tree for each memory access requesting device, for detecting memory access requests in flight. An interface unit is implemented associated with each processor requesting synchronization. The interface unit includes multiple generation completion detectors. The generation count and reclaim pointer do not pass one another.

  4. IEEE TRANSACTIONS ON MAGNETICS, VOL. 41, NO. 10, OCTOBER 2005 3823 Design of a Superhigh-Speed Cryogenic Permanent

    E-Print Network [OSTI]

    Wu, Thomas

    and simulation of a superhigh-speed permanent magnet synchronous motor (PMSM) that operates in the cryogenic temperature of 77 K. The designed PMSM is used to drive a two-stage cryocooler for zero boil-off and long, and some tradeoffs used in the design. A prototype PMSM was built to verify the design methodology. Index

  5. AN "AC INDUCTOR" BASED GRID CONNECTED INVERTER

    E-Print Network [OSTI]

    AN "AC INDUCTOR" BASED GRID CONNECTED INVERTER Ilya Zeltser, Student Member, IEEE and Sam Ben proposes a soft switched Output Current Sourcing (OCS) grid connected inverter that applies a high sourcing inverters where the small disturbance at the line voltage may lead to current run away

  6. ACS Installation During SM3B Introduction

    E-Print Network [OSTI]

    Sirianni, Marco

    ACS Installation During SM3B Introduction: · Installed during SM3B in March 2002 · Powerful 3rd · Over-voltage Protection kit installed · Optical Control Electronics connected · New Outer Blanket Layer, and coronagraph ­ Solar Blind Channel (SBC) : HST's most sensitive ultraviolet photon-counting detector 115-180 nm

  7. Appendix AC Exceptions to Delegated Purchasing Authority

    E-Print Network [OSTI]

    Dyer, Bill

    Appendix AC Exceptions to Delegated Purchasing Authority Delegated purchasing authority for professions exempted by 18-4-132, MCA The following services are exempt from Purchasing Procedures per Montana provider - Expert witness hired for use in litigation, Hearings Officer hired in rulemaking and contested

  8. Physics and contentswww.manchester.ac.uk

    E-Print Network [OSTI]

    engineering, science and bioscience research councils. As a postgraduate student at The UniversityPhysics and Astronomy #12;contentswww.manchester.ac.uk 12 The University of Manchester 2 Physics to be part of The University of Manchester. If you choose to be a postgraduate student here you can join us

  9. An Efficient Control of a Series Connected Two-Synchronous Motor 5-Phase with Non Sinusoidal EMF Supplied by a Single 5-leg VSI: Experimental and

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Synchronous Machines (PMSM) connected in series. Even if the Electro-Motive Force (EMF) are trapezoidal

  10. Microporous Magnets

    SciTech Connect (OSTI)

    Dechambenoit, Pierre; Long, Jeffrey R.

    2011-01-01T23:59:59.000Z

    Combining porosity and magnetic ordering in a single material presents a significant challenge since magnetic exchange generally requires short bridges between the spin carriers, whereas porosity usually relies on the use of long diamagnetic connecting ligands. Despite this apparent incompatibility, notable successes have been achieved of late in generating truly microporous solids with high magnetic ordering temperatures. In this critical review, we give an overview of this emerging class of multifunctional materials, with particular emphasis on synthetic strategies and possible routes to new materials with improved properties (149 references).

  11. Low dimensional magnetism

    E-Print Network [OSTI]

    Kjall, Jonas Alexander

    2012-01-01T23:59:59.000Z

    Magnetism in Ultracold Gases 4 Magnetic phase diagram of aMagnetism . . . . . . . . . . . .1.3 Magnetism in condensedIntroduction 1 Brief introduction to magnetism 1.1 Classic

  12. Optimal Methodology for Synchronized Scheduling of Parallel Station Assembly with Air Transportation

    E-Print Network [OSTI]

    Ganesan, Viswanath Kumar

    We present an optimal methodology for synchronized scheduling of production assembly with air transportation to achieve accurate delivery with minimized cost in consumer electronics supply chain (CESC). This problem was ...

  13. Recording speech articulation in dialogue: Evaluating a synchronized double electromagnetic articulography setup

    E-Print Network [OSTI]

    Edinburgh, University of

    is the severity of electromagnetic interference between the two machines. Our results suggest that the synchronization method used yields an accuracy of approximately 1 ms. Electromagnetic interference was derived

  14. PHYSICAL REVIEW E 84, 016213 (2011) Isochronal chaos synchronization of delay-coupled optoelectronic oscillators

    E-Print Network [OSTI]

    Illing, Lucas

    -coupled optoelectronic oscillators Lucas Illing,* Cristian D. Panda, and Lauren Shareshian Department of Physics, Reed; published 19 July 2011) We study experimentally chaos synchronization of nonlinear optoelectronic true for optical and optoelectronic devices that operate at technologically relevant radio frequen

  15. Integrating the Army Geospatial Enterprise : synchronizing geospatial-intelligence to the dismounted soldier

    E-Print Network [OSTI]

    Richards, James E., S.M. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    The Army's Geospatial Enterprise (AGE) has an emerging identity and value proposition arising from the need to synchronize geospatial information activities across the Army in order to deliver value to military decision ...

  16. Synchronization transitions in ensembles of noisy oscillators with bi-harmonic coupling

    E-Print Network [OSTI]

    Vladimir Vlasov; Maxim Komarov; Arkady Pikovsky

    2014-11-12T23:59:59.000Z

    We describe synchronization transitions in an ensemble of globally coupled phase oscillators with a bi-harmonic coupling function, and two sources of disorder - diversity of intrinsic oscillatory frequencies and external independent noise. Based on the self-consistent formulation, we derive analytic solutions for different synchronous states. We report on various non-trivial transitions from incoherence to synchrony where possible scenarios include: simple supercritical transition (similar to classical Kuramoto model), subcritical transition with large area of bistability of incoherent and synchronous solutions, and also appearance of symmetric two-cluster solution which can coexist with regular synchronous state. Remarkably, we show that the interplay between relatively small white noise and finite-size fluctuations can lead to metastable asynchronous solution.

  17. Optical phase dynamics in mutually coupled diode laser systems exhibiting power synchronization

    E-Print Network [OSTI]

    Vishwa Pal; Awadhesh Prasad; R Ghosh

    2011-11-10T23:59:59.000Z

    We probe the physical mechanism behind the known phenomenon of power synchronization of two diode lasers that are mutually coupled via their delayed optical fields. In a diode laser, the amplitude and the phase of the optical field are coupled by the so-called linewidth enhancement factor, $\\alpha$. In this work, we explore the role of optical phases of the electric fields in amplitude (and hence power) synchronization through $\\alpha$ in such mutually delay-coupled diode laser systems. Our numerical results show that the synchronization of optical phases drives the powers of lasers to synchronized death regimes. We also find that as $\\alpha$ varies for different diode lasers, the system goes through a sequence of in-phase amplitude-death states. Within the windows between successive amplitude-death regions, the cross-correlation between the field amplitudes exhibits a universal power-law behaviour with respect to $\\alpha$.

  18. A New, Iterative, Synchronous-Response Algorithm for Analyzing the Morton Effect

    E-Print Network [OSTI]

    Saha, Rohit

    2012-02-14T23:59:59.000Z

    analyzes the Morton Effect as a synchronous response problem with excitations from: (1) mechanical imbalance, (2) induced thermal bent shaft moments, and (3) mechanical imbalance that is induced by thermal bow. A general elliptical orbit can be decomposed...

  19. Controlling Magnetism at the Nanoscale

    E-Print Network [OSTI]

    Wong, Jared

    2012-01-01T23:59:59.000Z

    Manipulation of Magnetism - External148 Conclusion A The Magnetism Cheat Sheet A.1 Magnetic157 A.2 Magnetism Unit Conversion

  20. The effect of cisclomiphene on lambing rate and synchronization in sheep

    E-Print Network [OSTI]

    Beaver, Larry Jeff

    1972-01-01T23:59:59.000Z

    THE EFFECT OF CISCLOMIPHENE ON LAMBING RATE AND SYNCHRONIZATION IN SHEEP A Thesis by LARRY JEFF BEAVER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... December 1972 Major Subject: Physiology of Reproduction THE EFFECT OF CISCLOMIPHENE ON LAMBING RATE AND SYNCHRONIZATION IN SHEEP A Thesis by LARRY JEFF BEAVER Approved as to style and content by: C azrman o Commrttee (Head of Department @C~g Me...

  1. Automated transmission line fault analysis using synchronized sampling at two ends

    SciTech Connect (OSTI)

    Kezunovic, M. [Texas A and M Univ., College Station, TX (United States)] [Texas A and M Univ., College Station, TX (United States); Perunicic, B. [Lamar Univ., Beaumont, TX (United States)] [Lamar Univ., Beaumont, TX (United States)

    1996-02-01T23:59:59.000Z

    This paper introduces a new approach to fault analysis using synchronized sampling. A digital fault recorder with Global Positioning System (GPS) satellite receiver is the source of data for this approach. Fault analysis functions, such as fault detection, classification and location are implemented for a transmission line using synchronized samples from two ends of a line. This technique can be extremely fast, selective and accurate, providing fault analysis performance that can not easily be matched by other known techniques.

  2. Automated transmission line fault analysis using synchronized sampling at two ends

    SciTech Connect (OSTI)

    Kezunovic, M. [Texas A and M Univ., College Station, TX (United States); Perunicic, B. [Lamar Univ., Beaumont, TX (United States)

    1995-12-31T23:59:59.000Z

    This paper introduces a new approach to fault analysis using synchronized sampling. A digital fault recorder with Global Positioning System (GPS) satellite receiver is the source of data for this approach. Fault analysis functions, such as fault detection, classification and location are implemented for a transmission line using synchronized samples from two ends of a line. This technique can be extremely fast, selective and accurate, providing fault analysis performance that can not easily be matched by other known techniques.

  3. Neutrino magnetic moment in a magnetized plasma

    E-Print Network [OSTI]

    N. V. Mikheev; E. N. Narynskaya

    2010-11-08T23:59:59.000Z

    The contribution of a magnetized plasma to the neutrino magnetic moment is calculated. It is shown that only part of the additional neutrino energy in magnetized plasma connecting with its spin and magnetic field strength defines the neutrino magnetic moment. It is found that the presence of magnetized plasma does not lead to the considerable increase of the neutrino magnetic moment in contrast to the results presented in literature previously.

  4. Magnetostrictive materials and method for improving AC characteristics in same

    DOE Patents [OSTI]

    Pulvirenti, Patricia P. (Chicago, IL); Jiles, David C. (Ames, IA)

    2001-08-14T23:59:59.000Z

    The present invention provides Terfenol-D alloys ("doped" Terfenol) having optimized performances under the condition of time-dependent magnetic fields. In one embodiment, performance is optimized by lowering the conductivity of Terfenol, thereby improving the frequency response. This can be achieved through addition of Group III or IV elements, such as Si and Al. Addition of these types of elements provides scattering sites for conduction electrons, thereby increasing resistivity by 125% which leads to an average increase in penetration depth of 80% at 1 kHz and an increase in energy conversion efficiency of 55%. The permeability of doped Terfenol remains constant over a wider frequency range as compared with undoped Terfenol. These results demonstrate that adding impurities, such as Si and Al, are effective in improving the ac characteristics of Terfenol. A magnetoelastic Gruneisen parameter, .gamma..sub.me, has also been derived from the thermodynamic equations of state, and provides another means by which to characterize the coupling efficiency in magnetostrictive materials on a more fundamental basis.

  5. THE ACS NEARBY GALAXY SURVEY TREASURY

    SciTech Connect (OSTI)

    Dalcanton, Julianne J.; Williams, Benjamin F.; Rosema, Keith; Gogarten, Stephanie M.; Christensen, Charlotte; Gilbert, Karoline; Hodge, Paul [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Seth, Anil C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dolphin, Andrew [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Holtzman, Jon [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger St., Las Cruces, NM 88003 (United States); Skillman, Evan D.; Weisz, Daniel [Department of Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, MN 55455 (United States); Cole, Andrew [School of Mathematics and Physics, University of Tasmania, Hobart, Tasmania (Australia); Girardi, Leo [Osservatorio Astronomico di Padova - INAF, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy); Karachentsev, Igor D. [Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnji Arkhyz, Karachai-Circessia Republic 369167 (Russian Federation); Olsen, Knut [NOAO, National Optical Astronomy Observatory 950 N. Cherry Ave., Tucson, AZ 85719 (United States); Freeman, Ken [Mount Stromlo Observatory, Research School of Astronomy and Astrophysics, The Australian National Univ., ACT 0200 (Australia); Gallart, Carme [Inst. de AstrofIsica de Canarias, VIa Lactea, s/n, 38200 La Laguna, Tenerife (Spain); Harris, Jason [Steward Observatory, Univ. of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); De Jong, Roelof S. [Space Telescope Science Inst., 3700 San Martin Dr., Baltimore, MD 21218 (United States)], E-mail: jd@astro.washington.edu, E-mail: ben@astro.washington.edu, E-mail: krosema@astro.washington.edu, E-mail: stephanie@astro.washington.edu, E-mail: christensen@astro.washington.edu, E-mail: fabio@astro.washington.edu, E-mail: trq@astro.washington.edu, E-mail: aseth@cfa.harvard.edu (and others)

    2009-07-15T23:59:59.000Z

    The ACS Nearby Galaxy Survey Treasury (ANGST) is a systematic survey to establish a legacy of uniform multi-color photometry of resolved stars for a volume-limited sample of nearby galaxies (D < 4 Mpc). The survey volume encompasses 69 galaxies in diverse environments, including close pairs, small and large groups, filaments, and truly isolated regions. The galaxies include a nearly complete range of morphological types spanning a factor of {approx}10{sup 4} in luminosity and star formation rate. The survey data consist of images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST), supplemented with archival data and new Wide Field Planetary Camera 2 (WFPC2) imaging taken after the failure of ACS. Survey images include wide field tilings covering the full radial extent of each galaxy, and single deep pointings in uncrowded regions of the most massive galaxies in the volume. The new wide field imaging in ANGST reaches median 50% completenesses of m {sub F475W} = 28.0 mag, m {sub F606W} = 27.3 mag, and m {sub F814W} = 27.3 mag, several magnitudes below the tip of the red giant branch (TRGB). The deep fields reach magnitudes sufficient to fully resolve the structure in the red clump. The resulting photometric catalogs are publicly accessible and contain over 34 million photometric measurements of >14 million stars. In this paper we present the details of the sample selection, imaging, data reduction, and the resulting photometric catalogs, along with an analysis of the photometric uncertainties (systematic and random), for both ACS and WFPC2 imaging. We also present uniformly derived relative distances measured from the apparent magnitude of the TRGB.

  6. Patterned Magnetic Nanostructures and Quantized Magnetic Disks

    E-Print Network [OSTI]

    , opens up new opportunities for engineering innovative magnetic materials and devices, developing ultra of magnetic nanostructures as small as 10 nm; 2) engineering of unique magnetic properties (such as domainPatterned Magnetic Nanostructures and Quantized Magnetic Disks STEPHEN Y. CHOU Invited Paper

  7. Petroglyphs, Lighting, and Magnetism

    E-Print Network [OSTI]

    Walker, Merle F

    2007-01-01T23:59:59.000Z

    1950 Electricity and Magnetism: Theory and Applications.I Petroglyphs, Lightning, and Magnetism | Walker Figure 8.I Petroglyphs, Lightning, and Magnetism | Walker Figure IL

  8. DC-DC converter current source fed naturally commutated brushless DC motor drive

    E-Print Network [OSTI]

    Khopkar, Rahul Vijaykumar

    2004-11-15T23:59:59.000Z

    ..............................................................................................1 2 Commutator and brushes.......................................................................................2 3 Back-emf of a three-phase PMSM........................................................................3 4 Power generated... machines and are usually called Permanent Magnet Synchronous Machine (PMSM). In PMSM machines, the slip rings are eliminated and the stator windings are equivalent to the stator windings in synchronous ac machines. While no power is required for field...

  9. IEEE PHOTONICS TECHNOLOGY LETTERS, VOL. 17, NO. 2, FEBRUARY 2005 483 Synchronously Pumped Optical Parametric Oscillator

    E-Print Network [OSTI]

    Keller, Ursula

    , and D. J. Richardson are with the Optoelec- tronics Research Center (ORC), University of Southampton, Southampton SO17 1BJ, U.K. (e-mail: anm@orc.soton.ac.uk; djr@orc.soton.ac.uk). Digital Object Identifier 10

  10. Low temperature magnetic properties of magnesium substituted YbMnO{sub 3}

    SciTech Connect (OSTI)

    Sattibabu, Bhumireddi, E-mail: bsb.satti@gmail.com; Bhatnagar, Anil K., E-mail: bsb.satti@gmail.com; Mohan, Dasari, E-mail: bsb.satti@gmail.com; Das, Dibakar, E-mail: bsb.satti@gmail.com; Sundararaman, Mahadevan, E-mail: bsb.satti@gmail.com [School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad-500046 (India); Siruguri, Vasudeva; Rayaprol, Sudhindra [UGC-DAE Consortium for Scientific Research, Mumbai Centre, R-5 Shed, Bhabha Atomic Research Centre, Mumbai-400085 (India)

    2014-04-24T23:59:59.000Z

    Structural and magnetic properties of polycrystalline Yb{sub 1?x}Mg{sub x}MnO{sub 3} (x = 0, 0.05 and 0.10) hexagonal compounds prepared by solid state method, have been studied. The structural analyses of the samples were carried out by Rietveld analysis of neutron diffraction data. With increasing Mg content, we find that the lattice parameter a decreases and c increases whereas the overall Mn-O bond length decreases. Magnetization measured as a function of magnetic field at 2.5 K exhibits hysteresis, which is attributed to ferromagnetic like ordering of Yb{sup 3+} sublattice. Temperature dependence of ac magnetic susceptibility, ?{sub ac}(T), shows no signature of spin-glass behavior. ?(T) exhibits a sudden increase at low temperatures which is due to ordering of Yb{sup 3+} sublattice.

  11. Magnetic Catalysis vs Magnetic Inhibition

    E-Print Network [OSTI]

    Kenji Fukushima; Yoshimasa Hidaka

    2012-09-06T23:59:59.000Z

    We discuss the fate of chiral symmetry in an extremely strong magnetic field B. We investigate not only quark fluctuations but also neutral meson effects. The former would enhance the chiral-symmetry breaking at finite B according to the Magnetic Catalysis, while the latter would suppress the chiral condensate once B exceeds the scale of the hadron structure. Using a chiral model we demonstrate how neutral mesons are subject to the dimensional reduction and the low dimensionality favors the chiral-symmetric phase. We point out that this effect, the Magnetic Inhibition, can be a feasible explanation for recent lattice-QCD data indicating the decreasing behavior of the chiral-restoration temperature with increasing B.

  12. Study and Development of Anti-Islanding Control for Synchronous Machine-Based Distributed Generators: November 2001--March 2004

    SciTech Connect (OSTI)

    Ye, Z.

    2006-03-01T23:59:59.000Z

    This report summarizes the study and development of new active anti-islanding control schemes for synchronous machine-based distributed generators, including engine generators and gas turbines.

  13. Magnetic Stereoscopy

    E-Print Network [OSTI]

    Thomas Wiegelmann; Bernd Inhester

    2006-12-21T23:59:59.000Z

    The space mission STEREO will provide images from two viewpoints. An important aim of the STEREO mission is to get a 3D view of the solar corona. We develop a program for the stereoscopic reconstruction of 3D coronal loops from images taken with the two STEREO spacecraft. A pure geometric triangulation of coronal features leads to ambiguities because the dilute plasma emissions complicates the association of features in image 1 with features in image 2. As a consequence of these problems the stereoscopic reconstruction is not unique and multiple solutions occur. We demonstrate how these ambiguities can be resolved with the help of different coronal magnetic field models (potential, linear and non-linear force-free fields). The idea is that, due to the high conductivity in the coronal plasma, the emitting plasma outlines the magnetic field lines. Consequently the 3D coronal magnetic field provides a proxy for the stereoscopy which allows to eliminate inconsistent configurations. The combination of stereoscopy and magnetic modelling is more powerful than one of these tools alone. We test our method with the help of a model active region and plan to apply it to the solar case as soon as STEREO data become available.

  14. ac losses: Topics by E-print Network

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

    23 24 25 Next Page Last Page Topic Index 1 Transport AC loss in high temperature superconducting coils University of Cambridge - Dspace Summary: 's electromagnetic properties and...

  15. www.sheffield.ac.uk/careers Develop Your

    E-Print Network [OSTI]

    Martin, Stephen John

    Marketplace' run by the Careers Service and HSBC Bank www.shef. ac.uk/careers/students/advice/sfs. 10. If you

  16. Superconducting Magnet Division

    E-Print Network [OSTI]

    Superconducting Magnet Division DOE NP Program Review - July 06 1 Brookhaven Magnet Division - Nuclear Physics Program Support Activities Superconducting Magnet Program RHIC Operations Support Spin Summary Peter Wanderer, DOE review, July 25, 2006 Acting Head, Superconducting Magnet Division #12

  17. AVTA Voltec AC Level 1 and Level 2 Charging Systems Testing Results...

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

    Eaton AC Level 2 Charging System Testing Results AVTA: Aerovironment AC Level 2 Charging System Testing Results AVTA: Siemens-VersiCharge AC Level 2 Charging System Testing Results...

  18. E-Print Network 3.0 - ac voltage standard Sample Search Results

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

    "volts, AC"), the "secondary" voltage is roughly 6 VAC. We shall use the "Universal Transformer... :" conversion of AC to DC You can use a diode to convert the AC voltage of the...

  19. E-Print Network 3.0 - ac systems Sample Search Results

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

    AC DC SYSTEMS Christopher L. DeMarco Claudio A. Ca... reasonably detailed third order HVDC dynamics along with ac system models that include reactive ows... strong" ac systems,...

  20. E-Print Network 3.0 - ac graftrope system Sample Search Results

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

    AC DC SYSTEMS Christopher L. DeMarco Claudio A. Ca... reasonably detailed third order HVDC dynamics along with ac system models that include reactive ows... strong" ac systems,...

  1. A new measure of phase synchronization for a pair of time series and seizure focus localization

    E-Print Network [OSTI]

    Kaushik Majumdar

    2006-12-22T23:59:59.000Z

    Defining and measuring phase synchronization in a pair of nonlinear time series are highly nontrivial. This can be done with the help of Fourier transform, when it exists, for a pair of stored (hence stationary) signals. In a time series instantaneous phase is often defined with the help of Hilbert transform. In this paper phase of a time series has been defined with the help of Fourier transform. This gives rise to a deterministic method to detect phase synchronization in its most general form between a pair of time series. Since this is a stricter method than the statistical methods based on instantaneous phase, this can be used for lateralization and source localization of epileptic seizures with greater accuracy. Based on this method a novel measure of phase synchronization, called syn function, has been defined, which is capable of quantifying neural phase synchronization and asynchronization as important parameters of epileptic seizure dynamics. It has been shown that such a strict measure of phase synchronization has potential application in seizure focus localization from scalp electroencephalogram (EEG) data, without any knowledge of electrical conductivity of the head.

  2. Brushless machine having ferromagnetic side plates and side magnets

    DOE Patents [OSTI]

    Hsu, John S

    2012-10-23T23:59:59.000Z

    An apparatus is provided having a cylindrical stator and a rotor that is spaced from a stator to define an annular primary air gap that receives AC flux from the stator. The rotor has a plurality of longitudinal pole portions disposed parallel to the axis of rotation and alternating in polarity around a circumference of the rotor. Each longitudinal pole portion includes portions of permanent magnet (PM) material and at least one of the longitudinal pole portions has a first end and an opposing second end and a side magnet is disposed adjacent the first end and a side pole is disposed adjacent the second end.

  3. Non-Linear Magnetic Ringing of Spin-Ordered Solid He-3

    E-Print Network [OSTI]

    Hu, Chia-Ren; HAM, TE.

    1981-01-01T23:59:59.000Z

    of preparing the initial state, not by switch- ing off a large dc field, but rather by applying a ~eak ac magnetic pulse at the zero-field resonance fre- quency IIp/2rr for a sufficient duration, in order to drive the system to a finite deviation from...

  4. Observational Evidence of Changing Photospheric Vector Magnetic Fields Associated with Solar Flares

    E-Print Network [OSTI]

    of Sciences, 20A Datun Road, Chaoyang District, Beijing, 100012, China 3. Key Laboratory of Solar ActivityObservational Evidence of Changing Photospheric Vector Magnetic Fields Associated with Solar Flares University, Beijing 100875, China sjt@bao.ac.cn Received ; accepted Not to appear in Nonlearned J., 45. #12

  5. IEEE TRANSACTIONS ON MAGNETICS, VOL. 37, NO. 4, JULY 2001 2493 Coercivity, Time Dependence and Reversible

    E-Print Network [OSTI]

    Krishnan, Kannan M.

    of Physics at the University of Western Australia, Nedlands 6907, Australia (e-mail: woodward available magnets having energy products of up to 50 MGOe. A large body of work has been performed.S. Department of Energy, Division of Material Sciences, Office of Basic Energy Sciences under Contracts DE-AC02

  6. Pulsating Torque Reduction for Permanent Magnet Bojan Grcar, Peter Cafuta, Gorazd Stumberger

    E-Print Network [OSTI]

    Stankoviæ, Aleksandar

    vibration and acoustic noise which may be even amplified in variable speed drives when the torque frequencyPulsating Torque Reduction for Permanent Magnet AC Motors Bojan Grcar, Peter Cafuta, Gorazd motors are discussed in the paper. The pulsation torque is a consequence of the non-sinusoidal flux

  7. IEEE Transactions on Energy Conversion, Vol. 14, No. 4, December 1999 1043 OptimalCurrent Control Strategies for Surface-MountedPermanent-Magnet

    E-Print Network [OSTI]

    Chapman, Patrick

    . There has been considerable work in the area of choosing optimal current excitation of PMSM drives minimizing the rms stator Permanent-magnet synchronous machine (PMSM) drives current was set forth in [6 that In designing PMSM drives, two factors Of interest are would he difficult to implement in a real-time control

  8. AVTA: Siemens-VersiCharge AC Level 2 Charging System Testing...

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

    Siemens-VersiCharge AC Level 2 Charging System Testing Results AVTA: Siemens-VersiCharge AC Level 2 Charging System Testing Results The Vehicle Technologies Office's Advanced...

  9. AVTA: GE Energy WattStation AC Level 2 Charging System Testing...

    Energy Savers [EERE]

    2012 More Documents & Publications AVTA: Aerovironment AC Level 2 Charging System Testing Results AVTA: GE Smart Grid Capable AC Level 2 Testing Results AVTA: Siemens-VersiCharge...

  10. E-Print Network 3.0 - ac conduction properties Sample Search...

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

    measure the dynamical conductance of electrically contacted single-walled carbon nanotubes at dc and ac... between the ac ... Source: Burke, Peter - Department of Electrical...

  11. Magnetic Reconnection

    SciTech Connect (OSTI)

    Masaaki Yamada, Russell Kulsrud and Hantao Ji

    2009-09-17T23:59:59.000Z

    We review the fundamental physics of magnetic reconnection in laboratory and space plasmas, by discussing results from theory, numerical simulations, observations from space satellites, and the recent results from laboratory plasma experiments. After a brief review of the well-known early work, we discuss representative recent experimental and theoretical work and attempt to interpret the essence of significant modern findings. In the area of local reconnection physics, many significant findings have been made with regard to two- uid physics and are related to the cause of fast reconnection. Profiles of the neutral sheet, Hall currents, and the effects of guide field, collisions, and micro-turbulence are discussed to understand the fundamental processes in a local reconnection layer both in space and laboratory plasmas. While the understanding of the global reconnection dynamics is less developed, notable findings have been made on this issue through detailed documentation of magnetic self-organization phenomena in fusion plasmas. Application of magnetic reconnection physics to astrophysical plasmas is also brie y discussed.

  12. www.swansea.ac.uk Health & Safety Office

    E-Print Network [OSTI]

    Martin, Ralph R.

    : falling, type of work, frequency, ladders Machinery: moving parts, safety guards, entrapment, serv / maintwww.swansea.ac.uk Health & Safety Office Safety Tours and Inspections Ron Knuszka Safety Officer #12;www.swansea.ac.uk Health & Safety Office Objectives To be able to apply University Procedure

  13. www.mmu.ac.uk/careers Careers & Employability Service

    E-Print Network [OSTI]

    ;www.mmu.ac.uk/careers Identifying courses · www.prospects.ac.uk/search_courses.htm · www: Courses to allow you to enter certain professions Courses that build your skills in a new area Examples · MRes (taught prep for further research) These usually involve lectures for the first two terms

  14. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Contracting for wind generation EPRG Working an on- shore wind generator would be issued one ROC per MWh that they could sell in the market for ROCs@cam.ac.uk Publication July 2011 Financial Support ESRC RES-189-25-0155 #12;EPRG No 1120 1 Contracting for wind

  15. IT Services go.warwick.ac.uk/whatsnew2010

    E-Print Network [OSTI]

    Davies, Christopher

    to enable us to develop it as you would like. https://start.warwick.ac.uk/ Warwick Forward Warwick Forward. The domain itself must be registered with an external company by you. http://forward.warwick.ac.uk/ Files to navigate. · Files Transfer Utility. Enable access via a drive letter in Windows Explorer (or equivalent

  16. Electrostatic coalescence system with independent AC and DC hydrophilic electrodes

    DOE Patents [OSTI]

    Hovarongkura, A. David (Arlington, VA); Henry, Jr., Joseph D. (Morgantown, WV)

    1981-01-01T23:59:59.000Z

    An improved electrostatic coalescence system is provided in which independent AC and DC hydrophilic electrodes are employed to provide more complete dehydration of an oil emulsion. The AC field is produced between an AC electrode array and the water-oil interface wherein the AC electrode array is positioned parallel to the interface which acts as a grounded electrode. The emulsion is introduced into the AC field in an evenly distributed manner at the interface. The AC field promotes drop-drop and drop-interface coalescence of the water phase in the entering emulsion. The continuous oil phase passes upward through the perforated AC electrode array and enters a strong DC field produced between closely spaced DC electrodes in which small dispersed droplets of water entrained in the continuous phase are removed primarily by collection at hydrophilic DC electrodes. Large droplets of water collected by the electrodes migrate downward through the AC electrode array to the interface. All phase separation mechanisms are utilized to accomplish more complete phase separation.

  17. Turk J Elec Eng & Comp Sci, Vol.18, No.5, 2010, c TUBITAK doi:10.3906/elk-0906-55

    E-Print Network [OSTI]

    Hava, Ahmet

    investigation of shaft transducerless speed and position control of ac induction and interior permanent magnet estimation methods will be determined based on the motor type (induction or interior permanent magnet induction and interior permanent magnet synchronous motors will be presented. The study helps the motion

  18. Table 1. Design specifications of ultra-high speed PM motor. Supply voltage (V) 12

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    ) 1500 Rated torque (Nm) 0.0955 Rated speed (r/min) 150,000 Stator Core Permanent Magnet Shaft Coil Analysis of Ultra-High Speed Permanent-Magnet Motor Masaru Kano, and Toshihiko Noguchi Department@vos.nagaokaut.ac.jp Abstract This paper describes a design of an ultra-high speed (UHS) permanent-magnet (PM) synchronous motor

  19. Time Synchronization Attack in Smart Grid-Part I: Impact and Analysis

    E-Print Network [OSTI]

    Zhang, Zhenghao; Dimitrovski, Aleksandar D; Li, Husheng

    2012-01-01T23:59:59.000Z

    Many operations in power grids, such as fault detection and event location estimation, depend on precise timing information. In this paper, a novel Time Synchronization Attack (TSA) is proposed to attack the timing information in smart grid. Since many applications in smart grid utilize synchronous measurements and most of the measurement devices are equipped with global positioning system (GPS) for precise timing, it is highly probable to attack the measurement system by spoofing the GPS. The effectiveness of TSA is demonstrated for three applications of phasor measurement unit (PMU) in smart grid, namely transmission line fault detection, voltage stability monitoring and event locationing. The validity of TSA is demonstrated by numerical simulations.

  20. PHYSICAL REVIEW E 88, 022908 (2013) Synchronization of a Josephson junction array in terms of global variables

    E-Print Network [OSTI]

    Pikovsky, Arkady

    PHYSICAL REVIEW E 88, 022908 (2013) Synchronization of a Josephson junction array in terms of Josephson junctions with a common LCR load. Application of the Watanabe-Strogatz approach [Physica D 74, 197 of oscillating physical systems that being coupled synchronize are Josephson junctions [2]. In theoretical

  1. 430 IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS, VOL. 5, NO. 5, OCTOBER 2011 Phase-Synchronization Early Epileptic Seizure

    E-Print Network [OSTI]

    Genov, Roman

    -Synchronization Early Epileptic Seizure Detector VLSI Architecture Karim Abdelhalim, Student Member, IEEE, Vadim Smolyakov, Student Member, IEEE, and Roman Genov, Senior Member, IEEE Abstract--A low-power VLSI processor architecture that com- putes in real time the magnitude and phase-synchronization of two input neural signals

  2. Applied Cognitive Science (ACS) The ACS lab is directed by Dr. Frank Ritter, professor of IST and

    E-Print Network [OSTI]

    Squicciarini, Anna Cinzia

    Applied Cognitive Science (ACS) Laboratory The ACS lab is directed by Dr. Frank Ritter, professor during the 2012-2013 academic year, studies cognitive modeling, cognitive architectures, human-computer interaction (HCI), and learning. He has taught cognitive modeling, cognitive architectures, HCI, human factors

  3. Personal Web Archive: E-mail: waka@iplab.cs.tsukuba.ac.jp, {shizuki,jiro}@cs.tsukuba.ac.jp

    E-Print Network [OSTI]

    Tanaka, Jiro

    Personal Web Archive: Web E-mail: waka@iplab.cs.tsukuba.ac.jp, {shizuki,jiro}@cs.tsukuba.ac.jp Web Web Web Web Web Web Personal Web Archive Personal Web Archive: Support System for Browsing the Versions of Web Page Ryota WAKAMATSU Buntarou SHIZUKI Jiro TANAKA Graduate School of Systems

  4. this work, we examine acoustic feature changes in time-compressed speech processed using synchronized overlap-add SOLA method. Also,

    E-Print Network [OSTI]

    Russell, Daniel A.

    synchronized overlap-add SOLA method. Also, we discuss which parts of speech consonants or vowels are more

  5. Spatiotemporal synchronization of drift waves in a magnetron sputtering plasma

    SciTech Connect (OSTI)

    Martines, E.; Zuin, M.; Cavazzana, R.; Antoni, V.; Serianni, G.; Spolaore, M.; Vianello, N. [Consorzio RFX, Padova (Italy); Admek, J. [Institute of Plasma Physics AS CR, Prague (Czech Republic)

    2014-10-15T23:59:59.000Z

    A feedforward scheme is applied for drift waves control in a magnetized magnetron sputtering plasma. A system of driven electrodes collecting electron current in a limited region of the explored plasma is used to interact with unstable drift waves. Drift waves actually appear as electrostatic modes characterized by discrete wavelengths of the order of few centimeters and frequencies of about 100 kHz. The effect of external quasi-periodic, both in time and space, travelling perturbations is studied. Particular emphasis is given to the role played by the phase relation between the natural and the imposed fluctuations. It is observed that it is possible by means of localized electrodes, collecting currents which are negligible with respect to those flowing in the plasma, to transfer energy to one single mode and to reduce that associated to the others. Due to the weakness of the external action, only partial control has been achieved.

  6. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01T23:59:59.000Z

    A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

  7. The Synchronization Attack and Defense on Energy-Efficient Listen-Sleep Slotted MAC

    E-Print Network [OSTI]

    California at Davis, University of

    Xiaoming Lu, Matt Spear, Karl Levitt and S. Felix Wu Department of Computer Science UC Davis, Davis, CAThe Synchronization Attack and Defense on Energy-Efficient Listen-Sleep Slotted MAC Protocols, many listen- sleep Medium Access Control (MAC) protocols have been pro- posed to reduce energy

  8. Simplified Modelling and Control of a Synchronous Machine with VariableSpeed SixStep Drive

    E-Print Network [OSTI]

    Sanders, Seth

    of electrical power flow in the machine. Cost is a driving factor in the design of such a system, and the power frequency than PWM as well. II. VARIABLE­SPEED ELECTRIC MACHINE DRIVES While the choice of driveSimplified Modelling and Control of a Synchronous Machine with Variable­Speed Six­Step Drive

  9. Author Version -Electromotion Journal, 5, oct. 98, pp. 93-101. SPECIAL SYNCHRONOUS LINEAR ACTUATORS.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of the movement: - the indirect linear drives have been designed from a rotating electric motor as well as from. For long (and possibly unlimited) courses, the direct drives perform better, with the linear induction- coil actuators prove to be the most suitable. This paper focuses primarily on synchronous linear drives

  10. Robust Generator System Using PM Assisted Synchronous Reluctance Generator with Current-fed Drive

    E-Print Network [OSTI]

    Baek, Jeihoon

    2011-02-22T23:59:59.000Z

    action by making the PMa-SynRG operates as a generator, rectifying the phase voltages by means of the three-phase rectifier and feeding the power into the load. These features make the current-fed drive a good candidate for driving any type of synchronous...

  11. Nanomechanical-resonator-induced synchronization in Josephson junction arrays B. R. Trees* and S. Natu

    E-Print Network [OSTI]

    Stroud, David

    , and an interaction energy due to the piezo- electric effect between the NEM and the junctions. Phase lockingNanomechanical-resonator-induced synchronization in Josephson junction arrays B. R. Trees* and S that includes the following effects: the charging and Josephson energies of the junctions, dissipation

  12. Asynchronous or synchronous? A misleading choice. Scott Fairbanks and Simon Moore

    E-Print Network [OSTI]

    Moore, Simon

    elements of so- called asynchronous design in the construction of a so-called synchronous system placing equal delays in all pipeline stages. GasP mixes design elements from the asynchronous design style This work suggests that synchrony and asynchrony are not design choices but rather a collection of design

  13. Radioactivity-Synchronized Fluorescence Enhancement Using a Radionuclide Fluorescence-Quenched Dye

    E-Print Network [OSTI]

    Larson-Prior, Linda

    Radioactivity-Synchronized Fluorescence Enhancement Using a Radionuclide Fluorescence-Quenched Dye that demonstrates the feasibility of altering the fluorescence properties of an organic dye as a function effect on the dye fluorescence. Correlation of the radionuclide decay with the dye fluorescence

  14. Synchronization Assessment in Power Networks and Coupled Oscillators Florian Dorfler, Michael Chertkov, and Francesco Bullo

    E-Print Network [OSTI]

    Bullo, Francesco

    Synchronization Assessment in Power Networks and Coupled Oscillators Florian D¨orfler, Michael. F. D¨orfler and F. Bullo are with the Center for Control, Dynami- cal Systems and Computation Studies at LANL and with New Mexico Consortium, Los Alamos, NM 87544. Email: {dorfler

  15. Spectral Analysis of Synchronization in a Lossless Structure-Preserving Power Network Model

    E-Print Network [OSTI]

    Bullo, Francesco

    Spectral Analysis of Synchronization in a Lossless Structure-Preserving Power Network Model Florian D¨orfler Center for Control, Dynamical Systems, and Computation University of California at Santa Barbara Santa Barbara, CA 93106 Email: dorfler@engineering.ucsb.edu Francesco Bullo Center for Control

  16. Synchronization and Transient Stability in Power Networks and Non-Uniform Kuramoto Oscillators

    E-Print Network [OSTI]

    Florian Dorfler; Francesco Bullo

    2011-06-27T23:59:59.000Z

    Motivated by recent interest for multi-agent systems and smart power grid architectures, we discuss the synchronization problem for the network-reduced model of a power system with non-trivial transfer conductances. Our key insight is to exploit the relationship between the power network model and a first-order model of coupled oscillators. Assuming overdamped generators (possibly due to local excitation controllers), a singular perturbation analysis shows the equivalence between the classic swing equations and a non-uniform Kuramoto model. Here, non-uniform Kuramoto oscillators are characterized by multiple time constants, non-homogeneous coupling, and non-uniform phase shifts. Extending methods from transient stability, synchronization theory, and consensus protocols, we establish sufficient conditions for synchronization of non-uniform Kuramoto oscillators. These conditions reduce to and improve upon previously-available tests for the standard Kuramoto model. Combining our singular perturbation and Kuramoto analyses, we derive concise and purely algebraic conditions that relate synchronization and transient stability of a power network to the underlying system parameters and initial conditions.

  17. Integrating the Army Geospatial Enterprise: Synchronizing Geospatial-Intelligence to the Dismounted James E. Richards

    E-Print Network [OSTI]

    de Weck, Olivier L.

    1 Integrating the Army Geospatial Enterprise: Synchronizing Geospatial. #12;2 [This Page Intentionally Left Blank] #12;3 Army`s Geospatial Architecture: delivering Geospatial-Intelligence of complex and urban terrain to the dismounted Soldier by James E. Richards ABSTRACT The Army`s Geospatial

  18. Responding to environmental change: plastic responses1 vary little in a synchronous breeder.2

    E-Print Network [OSTI]

    Nussey, Dan

    The impact of environmental change on animal populations is strongly influenced by the10 ability. 2002).5 Determining how individuals base key life-history decisions on environmental cues is6 therefore1 Responding to environmental change: plastic responses1 vary little in a synchronous breeder.2 3

  19. Synconset Waves and Chains: Spiking Onsets in Synchronous Populations Predict and Are Predicted by

    E-Print Network [OSTI]

    Narayanan, Rishikesh

    Synconset Waves and Chains: Spiking Onsets in Synchronous Populations Predict and Are Predicted Synfire waves are propagating spike packets in synfire chains, which are feedforward chains embedded in random networks. Although synfire waves have proved to be effective quantification for network activity

  20. On Utility Accrual Processor Scheduling with Wait-Free Synchronization for Embedded Real-Time Software

    E-Print Network [OSTI]

    Ravindran, Binoy

    On Utility Accrual Processor Scheduling with Wait-Free Synchronization for Embedded Real-Time Software ABSTRACT We present the first wait-free utility accrual (UA) real-time scheduling algorithms for embedded real-time systems. UA scheduling algorithms allow application activities to be sub- ject to time/utility

  1. Method and apparatus to debug an integrated circuit chip via synchronous clock stop and scan

    DOE Patents [OSTI]

    Bellofatto, Ralph E. (Ridgefield, CT); Ellavsky, Matthew R. (Rochester, MN); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Gooding, Thomas M. (Rochester, MN); Haring, Rudolf A. (Cortlandt Manor, NY); Hehenberger, Lance G. (Leander, TX); Ohmacht, Martin (Yorktown Heights, NY)

    2012-03-20T23:59:59.000Z

    An apparatus and method for evaluating a state of an electronic or integrated circuit (IC), each IC including one or more processor elements for controlling operations of IC sub-units, and each the IC supporting multiple frequency clock domains. The method comprises: generating a synchronized set of enable signals in correspondence with one or more IC sub-units for starting operation of one or more IC sub-units according to a determined timing configuration; counting, in response to one signal of the synchronized set of enable signals, a number of main processor IC clock cycles; and, upon attaining a desired clock cycle number, generating a stop signal for each unique frequency clock domain to synchronously stop a functional clock for each respective frequency clock domain; and, upon synchronously stopping all on-chip functional clocks on all frequency clock domains in a deterministic fashion, scanning out data values at a desired IC chip state. The apparatus and methodology enables construction of a cycle-by-cycle view of any part of the state of a running IC chip, using a combination of on-chip circuitry and software.

  2. Rapid Prototyping for Digital Signal Processing Systems using Parameterized Synchronous Dataflow Graphs

    E-Print Network [OSTI]

    Bhattacharyya, Shuvra S.

    . Synchronous Dataflow (SDF), proposed in [2], is the first dataflow-based model of computation to gain broad optimization are developed in the context of SDF (e.g., see [3]). Although an important class of useful DSP applications can be modeled efficiently in SDF, the expressive power of SDF is restricted since SDF imposes

  3. Back to Basics: Homogeneous Representations of Multi-Rate Synchronous Dataflow Graphs

    E-Print Network [OSTI]

    Al Hanbali, Ahmad

    Synchronous dataflow (SDF) [1] is a popular class of models of computation and is used to model the temporal are particularly useful in the design of systems where worst-case guarantees on performance must be given. An SDF and processing elements. The class of SDF graphs that we focus on in this paper are called multi-rate SDF (MRSDF

  4. Blind Timing and Carrier Synchronization in Decode and Forward Cooperative Systems

    E-Print Network [OSTI]

    Durrani, Salman

    Blind Timing and Carrier Synchronization in Decode and Forward Cooperative Systems Ali A. Nasir for blind channel, timing and carrier offset estimation in a DF cooperative system with one source, M relays and one destination equipped with N antennas. In particular, we exploit blind source separation

  5. Dynamic synchronous/asynchronous replication ASSAF NATANZON,, EMC, Ben-Gurion University

    E-Print Network [OSTI]

    Bachmat, Eitan

    A Dynamic synchronous/asynchronous replication ASSAF NATANZON,, EMC, Ben-Gurion University EITAN remotely even if not all previous writes have been Author's addresses: A. Natanzon EMC Corp., Herzlia, Israel and department of Computer Science, Ben- Gurion University, Beer-Sheva, Israel, 84105. assaf.natanzon@emc

  6. Journal of Neuroscience Methods 170 (2008) 96110 Identifying repeating motifs in the activation of synchronized

    E-Print Network [OSTI]

    Jacob, Eshel Ben

    Cultured neuronal networks cultivated on micro-electrode arrays are a widely used tool network; Synchronized bursts; Clustering; In vitro; Culture; Micro-electrode array 1. Introduction Cultured neuronal networks cultivated on micro-electrode arrays are widely used as a tool for investigating

  7. SYNCHRONIZATION OF PALLIDAL ACTIVITY IN THE MPTP PRIMATE MODEL OF PARKINSONISM IS

    E-Print Network [OSTI]

    Bar-Gad, Izhar

    studies in human PD patients have found cells whose discharge is modulated in the tremor frequency range electrode studies revealed that in normal behaving animals most of the crosscorrelograms between pallidal neuronal pairs in the STN of human PD patients (Levy et al., 2000) were also synchronized in a higher

  8. Combining Retiming and Recycling to Optimize the Performance of Synchronous Circuits

    E-Print Network [OSTI]

    Carloni, Luca

    Combining Retiming and Recycling to Optimize the Performance of Synchronous Circuits Luca P, CA 94720-1772 Abstract Recycling was recently proposed as a system-level design tech- nique to facilitate the building of complex System-on-Chips (SOC) by assembling pre-designed components. Recycling

  9. Estimating Reliability and Throughput of Source-synchronous Wave-pipelined Interconnect

    E-Print Network [OSTI]

    Lemieux, Guy

    , we develop a statistical model of dynamic timing uncertainty. We show that it is important to distinguish between static and dynamic sources of tim- ing uncertainty, because source-synchronous wave pipelin- ing is much more sensitive to the latter. We use HSPICE simulations to develop a model for a wave

  10. A nonlinear observer to estimate unknown parameters during the synchronization of chaotic systems

    E-Print Network [OSTI]

    L. Torres

    2014-06-20T23:59:59.000Z

    This paper proposes an Extended-Kalman-Filter-like observer for parameter estimation during synchronization of chaotic systems. The exponential stability of the observer is guaranteed by a persistent excitation condition. This approach is shown to be suitable for various classical chaotic systems and several simulations are presented accordingly.

  11. Synchronous Ultra-Wide Band Wireless Sensors Networks for oil and gas exploration

    E-Print Network [OSTI]

    Savazzi, Stefano

    Synchronous Ultra-Wide Band Wireless Sensors Networks for oil and gas exploration Stefano Savazzi1 of new oil and gas reservoir. Seismic exploration requires a large number (500 ÷ 2000 nodes, MAC and network layer to develop wireless sensors networks tailored for oil (and gas) exploration

  12. Slew-rate dependence of tracer magnetization response in magnetic particle imaging

    SciTech Connect (OSTI)

    Shah, Saqlain A.; Krishnan, K. M., E-mail: kannanmk@uw.edu [Materials Science and Engineering, University of Washington, Seattle, Washington 98195 (United States); Ferguson, R. M. [LodeSpin Labs, P.O. Box 95632, Seattle, Washington 98145 (United States)

    2014-10-28T23:59:59.000Z

    Magnetic Particle Imaging (MPI) is a new biomedical imaging technique that produces real-time, high-resolution tomographic images of superparamagnetic iron oxide nanoparticle tracers. Currently, 25?kHz and 20?mT/?{sub 0} excitation fields are common in MPI, but lower field amplitudes may be necessary for patient safety in future designs. Here, we address fundamental questions about MPI tracer magnetization dynamics and predict tracer performance in future scanners that employ new combinations of excitation field amplitude (H{sub o}) and frequency (?). Using an optimized, monodisperse MPI tracer, we studied how several combinations of drive field frequencies and amplitudes affect the tracer's response, using Magnetic Particle Spectrometry and AC hysteresis, for drive field conditions at 15.5, 26, and 40.2?kHz, with field amplitudes ranging from 7 to 52?mT/?{sub 0}. For both fluid and immobilized nanoparticle samples, we determined that magnetic response was dominated by Nel reversal. Furthermore, we observed that the peak slew-rate (?H{sub o}) determined the tracer magnetic response. Smaller amplitudes provided correspondingly smaller field of view, sometimes resulting in excitation of minor hysteresis loops. Changing the drive field conditions but keeping the peak slew-rate constant kept the tracer response almost the same. Higher peak slew-rates led to reduced maximum signal intensity and greater coercivity in the tracer response. Our experimental results were in reasonable agreement with Stoner-Wohlfarth model based theories.

  13. HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

    SciTech Connect (OSTI)

    Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R

    1982-09-01T23:59:59.000Z

    Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

  14. Application of direct pulsewidth modulation scheme to AC-DC converters: - a way to reduce ripple

    E-Print Network [OSTI]

    Zhang, Yuemin

    1993-01-01T23:59:59.000Z

    Modulation (ISPWM), 4 Direct Pulsewidth Modulation (DPWM). 15 5 Single Phase Half Controlled PWM ac-dc Converter . 6 Single Phase Full controlled PWM ac-dc Converter . 18 18 7 Simulation of SPWM ac-dc Converter. 20 8 Output Voltage Spectra of SPWM ac... 30 Balanced Three Phase Inputs 31 Output Voltage of A Three Phase Full Controlled ac-dc SPWM Converter. 42 32 Output Voltage of A Three Phase Full Controlled ac-dc EPWM Con- verter 33 Output Voltage of A Three Phase Full Controlled ac-dc ISPWM Con...

  15. DC, AC and advanced EV propulsion systems

    SciTech Connect (OSTI)

    O'Neil, W.

    1983-08-01T23:59:59.000Z

    Battery development and liquid fuel availability and cost are still the pacing factors in wide scale electric vehicle introduction. Propulsion systems also require technical development, however, if electric vehicles are to be acceptable in the marketplace in competition against ICE vehicles. Eaton Corporation has undertaken a program designed to identify and investigate three broad types of propulsion systems in identical test vehicles on the same test track under conditions as similar as possible. Characteristics of dc, ac and advanced systems are compared to date, and projections of anticipated results and further work are provided. The compelling advantages of multiple mechanical ratios in EV propulsion systems are reviewed. An emerging, but less obvious, advantage is higher overall system efficiency.

  16. Interface Magnetism in Multiferroics

    E-Print Network [OSTI]

    He, Qing

    2011-01-01T23:59:59.000Z

    1.2.1 Magnetism . . . . . . . . . . . . . . . . . . . 1.2.2domain walls . . . . . 3 Magnetism of domain walls in BiFeOof electrical control of magnetism in mixed phase BiFeO 3

  17. Nanostructured magnetic materials

    E-Print Network [OSTI]

    Chan, Keith T.

    2011-01-01T23:59:59.000Z

    Magnetism and Magnetic Materials Conference, Atlanta, GA (Nanostructured Magnetic Materials by Keith T. Chan Doctor ofinduced by a Si-based material occurs at a Si/Ni interface

  18. Optimal design of AC filter circuits in HVDC converter stations

    SciTech Connect (OSTI)

    Saied, M.M.; Khader, S.A. [Kuwait Univ. (Kuwait). Electrical and Computer Engineering Dept.

    1995-12-31T23:59:59.000Z

    This paper investigates the reactive power as well as the harmonic conditions on both the valve and the AC-network sides of a HVDC converter station. The effect of the AC filter circuits is accurately modeled. The program is then augmented by adding an optimization routine. It can identify the optimal filter configuration, yielding the minimum current distortion factor at the AC network terminals for a prespecified fundamental reactive power to be provided by the filter. Several parameter studies were also conducted to illustrate the effect of accidental or intentional deletion of one of the filter branches.

  19. Contract Number: DE-AC05-76RL01830 Modification M705

    E-Print Network [OSTI]

    #12;#12;Contract Number: DE-AC05-76RL01830 Modification M705 #12;Contract Number: DE-AC05-76RL01830 Modification M705 #12;Contract Number: DE-AC05-76RL01830 Modification M705 #12;Contract Number: DE-AC05-76RL01830 Modification M705 #12;Contract Number: DE-AC05-76RL01830 Modification M705 #12;Contract Number: DE

  20. Error field and magnetic diagnostic modeling for W7-X

    SciTech Connect (OSTI)

    Lazerson, Sam A. [PPPL; Gates, David A. [PPPL; NEILSON, GEORGE H. [PPPL; OTTE, M.; Bozhenkov, S.; Pedersen, T. S.; GEIGER, J.; LORE, J.

    2014-07-01T23:59:59.000Z

    The prediction, detection, and compensation of error fields for the W7-X device will play a key role in achieving a high beta (? = 5%), steady state (30 minute pulse) operating regime utilizing the island divertor system [1]. Additionally, detection and control of the equilibrium magnetic structure in the scrape-off layer will be necessary in the long-pulse campaign as bootstrapcurrent evolution may result in poor edge magnetic structure [2]. An SVD analysis of the magnetic diagnostics set indicates an ability to measure the toroidal current and stored energy, while profile variations go undetected in the magnetic diagnostics. An additional set of magnetic diagnostics is proposed which improves the ability to constrain the equilibrium current and pressure profiles. However, even with the ability to accurately measure equilibrium parameters, the presence of error fields can modify both the plasma response and diverter magnetic field structures in unfavorable ways. Vacuum flux surface mapping experiments allow for direct measurement of these modifications to magnetic structure. The ability to conduct such an experiment is a unique feature of stellarators. The trim coils may then be used to forward model the effect of an applied n = 1 error field. This allows the determination of lower limits for the detection of error field amplitude and phase using flux surface mapping. *Research supported by the U.S. DOE under Contract No. DE-AC02-09CH11466 with Princeton University.

  1. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    Superconducting 30-MJ Energy Storage Coil", Proc. 19 80 ASC,Superconducting Magnetic Energy Storage Plant", IEEE Trans.SlIperconducting Magnetic Energy Storage Unit", in Advances

  2. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    Design of the BPA Superconducting 30-MJ Energy Storagefor a Utility Scale Superconducting Magnetic Energy Storagefor a Lnrge Scale Superconducting Magnetic Energy Storage

  3. Magnet power system for the Microwave Tokamak Experiment (MTX)

    SciTech Connect (OSTI)

    Jackson, M.C.; Musslewhite, R.C.

    1987-10-07T23:59:59.000Z

    The system configuration, layout, and general philosophy for the MTX magnet power system is described. The vast majority of the magnet power equipment was quite successfully used on the ALCATOR-C experiment at the Massachusetts Institute of Technology. The AC power for the magnet system at MIT was obtained from a 225MVA alternator. The power for the system at LLNL is obtained directly from the local utility's 230 kV line. This installation, therefore, necessitates the addition of a great deal of equipment in ranges from new switchgear in the substation to using existing switchgear obtained from MIT as contractors for intershop electrical isolation as well as safety isolation for personnel entry into the experimental area. Additionally, some discussion is made of the unique layout of this facility and the tradeoffs made to accommodate them. 2 refs., 6 figs.

  4. ac linear positioning: Topics by E-print Network

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

    USA kimik@yonsei.ac.kr Abstract- In this paper, one linear tapered slot antenna (LTSA), backed Tentzeris, Manos 187 The Square Root Law Requires a Linear Key Andrew D. Ker...

  5. INTERPRETATION OF AC IMPEDANCE MEASUREMENTS IN SOLIDS* J. Ross Macdonald

    E-Print Network [OSTI]

    Macdonald, James Ross

    = INTERPRETATION OF AC IMPEDANCE MEASUREMENTS IN SOLIDS* J. Ross Macdonald Department of Physics Foundation (Grant No. DMR 75-10739). 81 #12;82 PERTINENT PARAMETERS J.R. MACDONALD Figure 1 shows

  6. acs morphological study: Topics by E-print Network

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

    (more) Yang, Emma Yunyi 2013-01-01 29 Study of supplementary controls for embedded HVDC links in a AC power system. Open Access Theses and Dissertations Summary: ??This...

  7. 10.1071/SR10009_AC1 CSIRO 20102

    E-Print Network [OSTI]

    Lehmann, Johannes

    10.1071/SR10009_AC1 ©CSIRO 20102 Accessory Publication: Australian Journal of Soil Research, 2010 recovered from the supernatant by22 centrifugation at 2000 x G. Samples where then washed 3 times

  8. Cognitive Radio Network {swjang, sbahk}@netlab.snu.ac.kr

    E-Print Network [OSTI]

    Bahk, Saewoong

    2010 Cognitive Radio Network , , {swjang, sbahk}@netlab.snu.ac.kr Analysis of Average Opportunities in Cognitive Radio Networks Seowoo Jang, Saewoong Bahk INMC, EECS, Seoul National University Cognitive Radio Network . Primary user

  9. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Contracting for wind generation EPRG to the current Renewable Obligation Certificates, ROCs, where an on-shore wind generator receives one ROC

  10. acs presspac: Topics by E-print Network

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

    limits. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise from de Gispert, Adri 344 www.eprg.group.cam.ac.uk...

  11. ac microsized gliding: Topics by E-print Network

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

    limits. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise from de Gispert, Adri 417 www.eprg.group.cam.ac.uk...

  12. acs evidence based: Topics by E-print Network

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

    limits. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise from de Gispert, Adri 260 34CEN.ACS.ORG DECEMBER 23, 2013...

  13. ac surface photovoltage: Topics by E-print Network

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

    limits. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise from de Gispert, Adri 483 www.eprg.group.cam.ac.uk...

  14. acute cholecystitis ac: Topics by E-print Network

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

    limits. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise from de Gispert, Adri 384 www.eprg.group.cam.ac.uk...

  15. Microfluidics {sjauh, btzhang}@bi.snu.ac.kr

    E-Print Network [OSTI]

    Microfluidics {sjauh, btzhang}@bi.snu.ac.kr Solving Shortest Path Problems Using Microfluidics Sahng-Joon Auh and Byoung-Tak Zhang Biointelligence Lab, School of Computer Science and Engineering Seoul National University . microfluidics MEMS

  16. www.arts.canterbury.ac.nz/internships Project Title

    E-Print Network [OSTI]

    Hickman, Mark

    , researching suppliers and material requirements. The intern will also do research about.arts.canterbury.ac.nz/internships Necessary Qualifications: Major/Minors(s): All majors in the B.A. especially those interested in media

  17. www.glasgow.ac.uk/parents Say hello to Glasgow

    E-Print Network [OSTI]

    Guo, Zaoyang

    Parents' Guide www.glasgow.ac.uk/parents #12;2 Welcome Say hello to Glasgow Choosing the right Satisfaction (National Student Survey). Contents Page 2 Welcome Say hello to Glasgow Pages3

  18. University Policy No.: AC1145 Classification: Academic and Students

    E-Print Network [OSTI]

    Victoria, University of

    and maintaining high quality programs of education and research, to ongoing improvement of those programsUniversity Policy No.: AC1145 Classification: Academic and Students Approving Authority: Senate ACADEMIC PROGRAM REVIEW Effective Date: October/04 Supersedes: November/85 Last Editorial

  19. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    are efficiency, sustainability and security of energy supplies (Euwww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Conceptualizing Energy Security EPRG Working Paper 1123 Cambridge Working Paper in Economics 1151 Christian Winzer Energy security is one of the main

  20. ac josephson effect: Topics by E-print Network

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

    in the dc mass currents voltage, a high frequency ac voltage is applied across a superconduct- ing Josephson junction, the dc, Dm 22eV, application of a dc voltage produces...

  1. www.kent.ac.uk/is/ Information Services

    E-Print Network [OSTI]

    Banaji,. Murad

    .kent.ac.uk/cmsds-local/ Installing `Putty' Download it from the web (if you have administrator privilages) www close to each other. A dark cursor will not show on a dark background. Ideally make either

  2. Development of an AC Module System: Final Technical Report

    SciTech Connect (OSTI)

    Suparna Kadam; Miles Russell

    2012-06-15T23:59:59.000Z

    The GreenRay Inc. program focused on simplifying solar electricity and making it affordable and accessible to the mainstream population. This was accomplished by integrating a solar module, micro-inverter, mounting and monitoring into a reliable, 'plug and play' AC system for residential rooftops, offering the following advantages: (1) Reduced Cost: Reduction in installation labor with fewer components, faster mounting, faster wiring. (2) Maximized Energy Production: Each AC Module operates at its maximum, reducing overall losses from shading, mismatch, or module downtime. (3) Increased Safety. Electrical and fire safety experts agree that AC Modules have significant benefits, with no energized wiring or live connections during installation, maintenance or emergency conditions. (4) Simplified PV for a Broader Group of Installers. Dramatic simplification of design and installation of a solar power system, enabling faster and more efficient delivery of the product into the market through well-established, mainstream channels. This makes solar more accessible to the public. (5) Broadened the Rooftop Market: AC Modules enable solar for many homes that have shading, split roofs, or obstructions. In addition, due to the smaller building block size of 200W vs. 1000W, homeowners with budget limitations can start small and add to their systems over time. Through this DOE program GreenRay developed the all-in-one AC Module system with an integrated PV Module and microinverter, custom residential mounting and performance monitoring. Development efforts took the product from its initial concept, through prototypes, to a commercial product sold and deployed in the residential market. This pilot deployment has demonstrated the technical effectiveness of the AC Module system in meeting the needs and solving the problems of the residential market. While more expensive than the traditional central inverter systems at the pilot scale, the economics of AC Modules become more and more favorable as the product matures and is made in high volumes. GreenRay's early customers have been highly enthusiastic about the AC Module system benefits.

  3. Adjustable Speed AC Motor Drives-Applications Problems

    E-Print Network [OSTI]

    Enjeti, P.

    Adjustable Speed AC Motor Drives Applications Problems by Dr. P. Enjeti Power Quality Laboratory Department ofElectrical Engineering Texas A&M University College Station, TX 77843 Tel: 409-845-7466 Fax: 409-845-6259 Email..., it generates side effects, some which have been recognized only recently. This paper presents a comprehensive coverage of application issues of PWM inverter controlled ac motor drives which include damage to motor insulation due to reflected voltages caused...

  4. Demodulation circuit for AC motor current spectral analysis

    DOE Patents [OSTI]

    Hendrix, Donald E. (Oak Ridge, TN); Smith, Stephen F. (Knoxville, TN)

    1990-12-18T23:59:59.000Z

    A motor current analysis method for the remote, noninvasive inspection of electric motor-operated systems. Synchronous amplitude demodulation and phase demodulation circuits are used singly and in combination along with a frequency analyzer to produce improved spectral analysis of load-induced frequencies present in the electric current flowing in a motor-driven system.

  5. Magnetic Imaging Wolfgang Kuch

    E-Print Network [OSTI]

    Kuch, Wolfgang

    Magnetic Imaging Wolfgang Kuch Freie Universit¨at Berlin, Institut f¨ur Experimentalphysik, Arnimallee 14, 14195 Berlin, Germany kuch@physik.fu-berlin.de Abstract. Imaging of magnetic domains has- ern techniques is used nowadays routinely for magnetic imaging of magnetic ma- terials

  6. Superconducting Magnet Division

    E-Print Network [OSTI]

    McDonald, Kirk

    Superconducting Magnet Division Ramesh Gupta 20T Target Solenoid with HTS Insert Solenoid Capture Laboratory New York, USA http://www.bnl.gov/magnets/staff/gupta #12;Superconducting Magnet Division Ramesh of HTS may significantly reduce the amount of Tungsten shielding · Summary #12;Superconducting Magnet

  7. A Lossy, Synchronization-Free, Race-Full, But Still Acceptably Accurate Parallel Space-Subdivision Tree Construction Algorithm

    E-Print Network [OSTI]

    Rinard, Martin

    2012-02-23T23:59:59.000Z

    We present a new synchronization-free space-subdivision tree construction algorithm. Despite data races, this algorithm produces trees that are consistent enough for the client Barnes-Hut center of mass and force computation ...

  8. Synchronized Position Hold Engage & Reorient Experimental Satellites Massachusetts Institute of Technology, Space Systems Laboratory partnered with Payload Systems, Inc.

    E-Print Network [OSTI]

    de Weck, Olivier L.

    multi-aperture telescope or interferometer Space based fuel depot Multi-vehicle Mars mission architectures Routine and autonomous formation flight is essential to the operation of these missions Long ranges Tethered Formation Flight Synchronized Wireless Autonomous Reconfigurable Modules (SWARM

  9. A Data Synchronization Service for Ad Hoc Groups Terry Coatta, Norman C. Hutchinson, Andrew Warfield and Joseph H. T. Wong

    E-Print Network [OSTI]

    Warfield, Andrew

    A Data Synchronization Service for Ad Hoc Groups Terry Coatta, Norman C. Hutchinson, Andrew: norm@cs.ubc.ca Computer Laboratory, University of Cambridge, Cambridge, United Kingdom Email: andrew

  10. Techniques for synchronization of X-Ray pulses to the pump laser in an ultrafast X-Ray facility

    E-Print Network [OSTI]

    Corlett, J.N.; Doolittle, L.; Schoenlein, R.; Staples, J.; Wilcox, R.; Zholents, A.

    2003-01-01T23:59:59.000Z

    synchronization of ultrafast x-ray pulses produced in theAccurate timing of ultrafast x-ray probe pulses emitted fromOF X-RAY PULSES TO THE PUMP LASER IN AN ULTRAFAST X-RAY

  11. Experimental investigation of subcooled flow boiling using synchronized high speed video, infrared thermography, and particle image velocimetry

    E-Print Network [OSTI]

    Phillips, Bren Andrew

    2014-01-01T23:59:59.000Z

    Subcooled flow boiling of water was experimentally investigated using high-speed video (HSV), infrared (IR) thermography, and particle image velocimetry (PIV) to generate a unique database of synchronized data. HSV allowed ...

  12. System and method for determining stator winding resistance in an AC motor using motor drives

    SciTech Connect (OSTI)

    Lu, Bin; Habetler, Thomas G; Zhang, Pinjia

    2013-02-26T23:59:59.000Z

    A system and method for determining the stator winding resistance of AC motors is provided. The system includes an AC motor drive having an input connectable to an AC source and an output connectable to an input terminal of an AC motor, a pulse width modulation (PWM) converter having switches therein to control current flow and terminal voltages in the AC motor, and a control system connected to the PWM converter. The control system generates a command signal to cause the PWM converter to control an output of the AC motor drive corresponding to an input to the AC motor, selectively generates a modified command signal to cause the PWM converter to inject a DC signal into the output of the AC motor drive, and determines a stator winding resistance of the AC motor based on the DC signal of at least one of the voltage and current.

  13. Portable Microwave Frequency Dissemination in Free Space and Implications on Ground-Satellite Synchronization

    E-Print Network [OSTI]

    Wang, Bo; Bai, Yu; Yuan, Yibo; Gao, Chao; Wang, Lijun

    2015-01-01T23:59:59.000Z

    Frequency dissemination and synchronization in free space plays an important role in global navigation satellite system (GNSS), radio astronomy and synthetic aperture radar (SAR). In this paper, we demonstrate a portable radio frequency (RF) dissemination scheme via free space using microwave antennas. The setup has a good environment adaptability and high dissemination stability. The frequency signal is disseminated at different distances ranging from 10 to 640 m with a fixed 10 Hz locking bandwidth, and the scaling law of dissemination stability on distance and averaging time is discussed. The preliminary extrapolation shows that the dissemination stability may reach $1\\times10^{-12}/s$ in ground-to-satellite synchronization, which far exceeds all present methods, and is worthy for further study.

  14. Method and system for controlling a synchronous machine over full operating range

    DOE Patents [OSTI]

    Walters, James E. (Carmel, IN); Gunawan, Fani S. (Westfield, IN); Xue, Yanhong (Westfield, IN)

    2002-01-01T23:59:59.000Z

    System and method for controlling a synchronous machine are provided. The method allows for calculating a stator voltage index. The method further allows for relating the magnitude of the stator voltage index against a threshold voltage value. An offset signal is generated based on the results of the relating step. A respective state of operation of the machine is determined. The offset signal is processed based on the respective state of the machine.

  15. New synchronous compensators for the Nelson River HVDC system; Planning requirements and specifications

    SciTech Connect (OSTI)

    Thio, C.V.; Davies, J.B. (Manitoba Hydro, Winnipeg, Manitoba (CA))

    1991-04-01T23:59:59.000Z

    The first units of Limestone Generating Station, the third plant on the Lower Nelson River in northern Manitoba, will come into service in the fall of 1990. Additional var compensation equipment is required at the inverter end of the Nelson River HVdc system to accommodate power from Limestone. This paper describes the system requirements of and the overall specification for the synchronous compensators selected to supply the reactive power and voltage support.

  16. Installation considerations for IGBT AC drives

    SciTech Connect (OSTI)

    Skibinski, G.L.

    1997-06-01T23:59:59.000Z

    In the last four years, Adjustable Speed ac Drive (ASD) manufacturers have migrated from Bipolar Junction Transistor (BJT) semiconductors to Insulated Gate Bipolar Transistors (IGBTs) as the preferred Output switching device. The advantage of IGBTs over BJTs is that device rise and fall time switching capability is 5 - 10 times faster, resulting in lower device switching loss and a more efficient drive. However, for a similar motor cable length as the BJT drive, the faster output voltage risetime of the IGBT drive may increase the dielectric voltage stress on the motor and cable due to a phenomenon called reflected wave. Faster output dv/dt transitions of IGBT drives also increase the possibility for phenomenon such as increased Common Mode (CM) electrical noise, Electromagnetic Interference (EMI) problems and increased capacitive cable charging current problems. Also, recent experience suggests any Pulse Width Modulated (PWM) drive with a steep fronted output voltage wave form may increase motor shaft voltage and lead to a bearing current phenomenon known as fluting. This paper provides a basic understanding of these issues, as well as solutions, to insure a successful drive system installation.

  17. Adaptive vibration control using synchronous demodulation with machine tool controller motor commutation

    DOE Patents [OSTI]

    Hopkins, David James (Livermore, CA)

    2008-05-13T23:59:59.000Z

    A control system and method for actively reducing vibration in a spindle housing caused by unbalance forces on a rotating spindle, by measuring the force-induced spindle-housing motion, determining control signals based on synchronous demodulation, and provide compensation for the measured displacement to cancel or otherwise reduce or attenuate the vibration. In particular, the synchronous demodulation technique is performed to recover a measured spindle housing displacement signal related only to the rotation of a machine tool spindle, and consequently rejects measured displacement not related to spindle motion or synchronous to a cycle of revolution. Furthermore, the controller actuates at least one voice-coil (VC) motor, to cancel the original force-induced motion, and adapts the magnitude of voice coil signal until this measured displacement signal is brought to a null. In order to adjust the signal to a null, it must have the correct phase relative to the spindle angle. The feedback phase signal is used to adjust a common (to both outputs) commutation offset register (offset relative to spindle encoder angle) to force the feedback phase signal output to a null. Once both of these feedback signals are null, the system is compensating properly for the spindle-induced motion.

  18. Reactive Power Laboratory: Synchronous Condenser Testing&Modeling Results - Interim Report

    SciTech Connect (OSTI)

    Henry, SD

    2005-09-27T23:59:59.000Z

    The subject report documents the work carried out by Oak Ridge National Laboratory (ORNL) during months 5-7 (May-July 2005) of a multi-year research project. The project has the overall goal of developing methods of incorporating distributed energy (DE) that can produce reactive power locally and for injecting into the distribution system. The objective for this new type of DE is to be able to provide voltage regulation and dynamic reactive power reserves without the use of extensive communication and control systems. The work performed over this three-month period focused on four aspects of the overall objective: (1) characterization of a 250HP (about 300KVAr) synchronous condenser (SC) via test runs at the ORNL Reactive Power Laboratory; (2) development of a data acquisition scheme for collecting the necessary voltage, current and power readings at the synchronous condenser and on the distribution system; (3) development of algorithms for analyzing raw test data from the various test runs; and (4) validation of a steady-state model for the synchronous condenser via the use of a commercial software package to study its effects on the ORNL 13.8/2.4kV distribution network.

  19. A deterministic, gigabit serial timing, synchronization and data link for the RHIC LLRF

    SciTech Connect (OSTI)

    Hayes, T.; Smith, K.S.; Severino, F.

    2011-03-28T23:59:59.000Z

    A critical capability of the new RHIC low level rf (LLRF) system is the ability to synchronize signals across multiple locations. The 'Update Link' provides this functionality. The 'Update Link' is a deterministic serial data link based on the Xilinx RocketIO protocol that is broadcast over fiber optic cable at 1 gigabit per second (Gbps). The link provides timing events and data packets as well as time stamp information for synchronizing diagnostic data from multiple sources. The new RHIC LLRF was designed to be a flexible, modular system. The system is constructed of numerous independent RF Controller chassis. To provide synchronization among all of these chassis, the Update Link system was designed. The Update Link system provides a low latency, deterministic data path to broadcast information to all receivers in the system. The Update Link system is based on a central hub, the Update Link Master (ULM), which generates the data stream that is distributed via fiber optic links. Downstream chassis have non-deterministic connections back to the ULM that allow any chassis to provide data that is broadcast globally.

  20. Transient Stability Analysis in Power Networks and Synchronization of Non-uniform Kuramoto Oscillators

    E-Print Network [OSTI]

    Dorfler, Florian

    2009-01-01T23:59:59.000Z

    In the current discussion about the future smart power grid one of the major problems is that of transient stability, which is the power system's ability to maintain synchronism in the presence of transient disturbances. This paper proposes a novel network-based approach to this problem resulting in concise and purely algebraic conditions that relate transient stability of a power network to the underlying network parameters and state. Our technical approach considers a network-reduction model of a power system with non-trivial transfer conductances and bridges the gap from transient stability analysis to an apparently related problem in physics, the synchronization of coupled Kuramoto oscillators. In a singular perturbation analysis it is shown that transient stability analysis of a power network model reduces on a long time-scale to the problem of synchronizing non-uniform Kuramoto oscillators with multiple time constants, non-homogeneous coupling, and non-uniform phase-shifts. The analysis of the later syn...

  1. Heterogeneous delays making parents synchronized: A coupled maps on Cayley tree model

    E-Print Network [OSTI]

    Aradhana Singh; Sarika Jalan

    2014-06-18T23:59:59.000Z

    We study the phase synchronized clusters in the diffusively coupled maps on the Cayley tree networks for heterogeneous delay values. Cayley tree networks comprise of two parts: the inner nodes and the boundary nodes. We find that heterogeneous delays lead to various cluster states, such as; (a) cluster state consisting of inner nodes and boundary nodes, and (b) cluster state consisting of only boundary nodes. The former state may comprise of nodes from all the generations forming self-organized cluster or nodes from few generations yielding driven clusters depending upon on the parity of heterogeneous delay values. Furthermore, heterogeneity in delays leads to the lag synchronization between the siblings lying on the boundary by destroying the exact synchronization among them. The time lag being equal to the difference in the delay values. The Lyapunov function analysis sheds light on the destruction of the exact synchrony among the last generation nodes. To the end we discuss the relevance of our results with respect to their applications in the family business as well as in understanding the occurrence of genetic diseases.

  2. Static scheduling of synchronous data flow programs for digital signal processing

    SciTech Connect (OSTI)

    Lee, E.A.; Messerschmitt, D.G.

    1987-01-01T23:59:59.000Z

    Large grain data flow (LGDF) programming is natural and convenient for describing digital signal processing (DSP) systems, but its runtime overhead is costly in real time or cost-sensitive applications. In some situations, designers are not willing to squander computing resources for the sake of programmer convenience. This is particularly true when the target machine is a programmable DSP chip. However, the runtime overhead inherent in most LGDF implementations is not required for most signal processing systems because such systems are mostly synchronous (in the DSP sense). Synchronous data flow (SDF) differs from traditional data flow in that the amount of data produced and consumed by a data flow node is specified a priori for each input and output. This is equivalent to specifying the relative sample rates in signal processing system. This means that the scheduling of SDF nodes need not be done at runtime, but can be done at compile time (statically), so the runtime overhead evaporates. The sample rates can all be different, which is not true of most current data-driven digital signal processing programming methodologies. Synchronous data flow is closely related to computation graphs, a special case of Petri nets. This self-contained paper develops the theory necessary to statically schedule SDF programs on single or multiple processors. A class of static (compile time) scheduling algorithms is proven valid, and specific algorithms are given for scheduling SDF systems onto single or multiple processors.

  3. DE-AC05-00OR22725 Section B--Page 1 of 7 DE-AC05-00OR22725

    E-Print Network [OSTI]

    .......................................................................... 5 #12;DE-AC05-00OR22725 Section B--Page 2 of 7 DE-AC05-000R22725 Modification No. 760 Section B Blank Page #12;DE-AC05-00OR22725 Section B--Page 3 of 7 DE-AC05-000R22725 Modification No. 760 Section B of 7 DE-AC05-000R22725 Modification No. 760 Section B 4) $267,518 for the project entitled "4500 Area

  4. E-Print Network 3.0 - advanced ac motor Sample Search Results

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

    for a QE2 synchronous motor... in motor applications < 110 the energy required for 4K refrigeration HTS enhances commercial economics... Motors and Generators HTS enables...

  5. Magnetic infrasound sensor

    DOE Patents [OSTI]

    Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)

    2006-11-14T23:59:59.000Z

    A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.

  6. Advantage of Increasing the Number of Airgap Surfaces in Synchronous Linear Actuators

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    permanent magnets or coiled excitation); and · Non-excited machines (with variable reluctance). Moreover, four types of coupling can be distinguished, depending on the nature and shape of the magnetic field is reduced in order to minimize the quantity of magnetic circuit; however, the physical limitations of airgap

  7. E-Print Network 3.0 - ac power distribution Sample Search Results

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

    Ray Summary: Capacitor Bias - T Figure 4 - AC Distribution Using a Bias-T Advantages of Power Distribution Using Bias... . In the case of AC power distribution with bias-T...

  8. DE-AC02-76SF00515 Apr2007/Rev 1

    E-Print Network [OSTI]

    Wechsler, Risa H.

    DE-AC02-76SF00515 Appendix B Apr2007/Rev 1 FY 2007 Contractor Performance Evaluation and Measurement Plan for Management and Operations ofthe Stanford Linear Accelerator Center J-B-i #12;DE-AC02

  9. Journal of Magnetism and Magnetic Materials ] (

    E-Print Network [OSTI]

    McHenry, Michael E.

    magnetic properties were measured with a vibrating sample magnetometer. The mass-specific power loss.40.Rs Keywords: Nanocrystalline alloys; Amorphous alloys; Field annealing; Power loss; Soft magnets the hysteretic power loss while maintaining high-temperature operability [4]. Other goals have included studies

  10. Recent lunar magnetism

    E-Print Network [OSTI]

    Buz, Jennifer

    2011-01-01T23:59:59.000Z

    The magnetization of young lunar samples (magnetic fields (e.g. core dynamo and long-lived impact plasma fields) have not been present within the last 1.5 Ga. To better ...

  11. Magnetic assisted statistical assembly

    E-Print Network [OSTI]

    Cheng, Diana I

    2008-01-01T23:59:59.000Z

    The objective of this thesis is to develop a process using magnetic forces to assemble micro-components into recesses on silicon based integrated circuits. Patterned SmCo magnetic thin films at the bottom of recesses are ...

  12. Sarah.Glynn@ed.ac.uk April 2008 Liberalising Islam: creating Brits of the Islamic Persuasion

    E-Print Network [OSTI]

    .Glynn@ed.ac.uk April 2008 1 Liberalising Islam: creating Brits of the Islamic Persuasion In common with other

  13. Larval ecology and synchronous reproduction of two crustacean species : Semibalanus balanoides in New England, USA and Gecarcinus quadratus in Veraguas, Panama

    E-Print Network [OSTI]

    Gyory, Joanna

    2011-01-01T23:59:59.000Z

    The environmental cues for synchronous reproduction were investigated for two highly abundant, ecologically important crustacean species: the temperate acorn barnacle, Semibalanus balanoides, and the tropical terrestrial ...

  14. Magnetic susceptibility in QCD

    E-Print Network [OSTI]

    V. D. Orlovsky; Yu. A. Simonov

    2014-05-12T23:59:59.000Z

    Magnetic susceptibility in the deconfined phase of QCD is calculated in a closed form using a recent general expression for the quark gas pressure in magnetic field. Quark selfenergies are entering the result via Polyakov line factors and ensure the total paramagnetic effect, increasing with temperature. A generalized form of magnetic susceptibility in nonzero magnetic field suitable for experimental and lattice measurements is derived, showing a good agreement with available lattice data.

  15. Magnetism Theory Group / POSTECH Magnetism Theory Group / POSTECH

    E-Print Network [OSTI]

    Min, Byung Il

    Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH J.H . Park et al. #12;'s of FeinCsm e tal The chargeandorbitalordering geom etryin YB a C o 2 O 5 S. K. Kwon etal .Magnetism Theory

  16. Magnetic nanohole superlattices

    DOE Patents [OSTI]

    Liu, Feng

    2013-05-14T23:59:59.000Z

    A magnetic material is disclosed including a two-dimensional array of carbon atoms and a two-dimensional array of nanoholes patterned in the two-dimensional array of carbon atoms. The magnetic material has long-range magnetic ordering at a temperature below a critical temperature Tc.

  17. Noble gas magnetic resonator

    DOE Patents [OSTI]

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2014-04-15T23:59:59.000Z

    Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.

  18. Contract No. DE-AC05-76RL01830 Modification M943

    E-Print Network [OSTI]

    Contract No. DE-AC05-76RL01830 Modification M943 SECTION J APPENDIX A ADVANCE UNDERSTANDINGS ON HUMAN RESOURCES COST Applicable to the Operation of PACIFIC NORTHWEST NATIONAL LABORATORY Contract No. DE-AC05-76RL01830 #12;Contract No. DE-AC05-76RL01830 Modification M943 J-A-1 Table of Contents

  19. Contract Number: DE-AC05-76RL01830 Modification M957

    E-Print Network [OSTI]

    Contract Number: DE-AC05-76RL01830 Modification M957 APPENDIX E STANDARDS OF PERFORMANCE-BASED FEE OF THE PACIFIC NORTHWEST NATIONAL LABORATORY #12;Contract Number: DE-AC05-76RL01830 Modification M957 APPENDIX E FOR MANAGEMENT AND OPERATIONS OF THE PACIFIC NORTHWEST NATIONAL LABORATORY #12;Contract Number: DE-AC05-76RL01830

  20. (mercury.yukawa.kyoto-u.ac.jp)ssh Permission denied (publickey).

    E-Print Network [OSTI]

    Shimizu, Akira

    SSH Q&A (mercury.yukawa.kyoto-u.ac.jp)ssh Permission denied (publickey). (1) ID ID ID (2) ssh -i () ssh -i $HOME/.ssh/id_yitp_rsa (UID)@mercury.yukawa.kyoto-u.ac.jp (3) (1)(2) Permission denied support@yukawa.kyoto-u.ac.jp (mercury

  1. E-Print Network 3.0 - ac magnetic susceptibility Sample Search...

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

    near their melting point. We present an experimental study of those effects... , the thermal convection in an insulating or conducting liquid, providing its ... Source: Ecole...

  2. "Permanent Magnet Generator-like AC Current Drive for Torroidal Fusion

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNG IHDR€ÍSolar Energy SystemsFebruary 7-8,MarchKnyszek,A.|

  3. Fingerprinting of bed sediment in theTay Estuary, Scotland: an environmental magnetism approach Hydrology and Earth System Sciences, 6(6), 10071016 (2002) EGS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Fingerprinting of bed sediment in theTay Estuary, Scotland: an environmental magnetism approach 1007 Hydrology and Earth System Sciences, 6(6), 1007­1016 (2002) © EGS Fingerprinting of bed sediment 9AL, Scotland Email of corresponding author: p.a.jenkins@dundee.ac.uk Abstract Sediment

  4. National High Magnetic Field Laboratory

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

    ANNUAL REPORT RESEARCH HIGHLIGHTS: CONDENSED MATTER SCIENCE Technique development, graphene, magnetism & magnetic materials, topological insulators, quantum fl uids & solids,...

  5. Synchronization of a Josephson junction array in terms of global variables

    E-Print Network [OSTI]

    Vladimir Vlasov; Arkady Pikovsky

    2013-04-08T23:59:59.000Z

    We consider an array of Josephson junctions with a common LCR-load. Application of the Watanabe-Strogatz approach [Physica D, v. 74, p. 197 (1994)] allows us to formulate the dynamics of the array via the global variables only. For identical junctions this is a finite set of equations, analysis of which reveals the regions of bistability of the synchronous and asynchronous states. For disordered arrays with distributed parameters of the junctions, the problem is formulated as an integro-differential equation for the global variables, here stability of the asynchronous states and the properties of the transition synchrony-asynchrony are established numerically.

  6. Estimation of the Dynamic States of Synchronous Machines Using an Extended Particle Filter

    SciTech Connect (OSTI)

    Zhou, Ning; Meng, Da; Lu, Shuai

    2013-11-11T23:59:59.000Z

    In this paper, an extended particle filter (PF) is proposed to estimate the dynamic states of a synchronous machine using phasor measurement unit (PMU) data. A PF propagates the mean and covariance of states via Monte Carlo simulation, is easy to implement, and can be directly applied to a non-linear system with non-Gaussian noise. The extended PF modifies a basic PF to improve robustness. Using Monte Carlo simulations with practical noise and model uncertainty considerations, the extended PFs performance is evaluated and compared with the basic PF and an extended Kalman filter (EKF). The extended PF results showed high accuracy and robustness against measurement and model noise.

  7. Effect of estrous synchronization on tubal ovum transport and fertilization in the ewe

    E-Print Network [OSTI]

    Deen, Travis Dale

    1971-01-01T23:59:59.000Z

    EFFECT OF ESTHOUS SINCHHGNIZATIGN CN 1UBAL Ol, "i'l" THANS'PGHT AND FEHTILIZATION IN TM E'uter A Thesis TH'. VIS DAD" D" EN gsr mp Submitted to the Graduate College of Te. . ss AB 'i Nniversitf in. fu' fillment of the reguirem nt... Approved as to style and content byt hairzan oi oozttit ee nead o t eparttttent) t ter-oar ) t ettt r) t tray 1971 ABSTRLOT Effect of Estrous Synchronization on Tubal Ovum Trans ort and Fertilization in the Ewe. (May 1971) Tra. -is Dale Beer', S. S...

  8. Magnetically attached sputter targets

    DOE Patents [OSTI]

    Makowiecki, D.M.; McKernan, M.A.

    1994-02-15T23:59:59.000Z

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

  9. Aircraft AC Generators: Hybrid System Modeling and Simulation

    E-Print Network [OSTI]

    Koutsoukos, Xenofon D.

    --Integrated Drive Generators (IDGs) are the main source of electrical power for a number of critical systems1 Aircraft AC Generators: Hybrid System Modeling and Simulation Ashraf Tantawy, Student Member is a difficult task. dq0 models have been developed for design and control of generators, but these models

  10. www.strath.ac.uk/engineering Faculty of Engineering

    E-Print Network [OSTI]

    Mottram, Nigel

    . The Faculty of Engineering wishes to thank all of our industrial partners who offer invaluable opportunitieswww.strath.ac.uk/engineering @StrathEng Faculty of Engineering Scholarships #12;Contents University of Strathclyde | Faculty of Engineering Scholarships Contents02 The Faculty of Engineering provides a wide range

  11. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Reforming Small Power Systems under Rabindra Nepal and Tooraj Jamasb The pioneering electricity sector reforms in developing Latin American of `successful and comprehensive electricity reforms' in many less-developed countries like Nepal. Nepal's power

  12. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Reforming Small Power Systems under Political Nepal and Tooraj Jamasb This paper assesses the electricity sector reforms across small power systems make power sector reform in Nepal and similar small systems a more complex process. As international

  13. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    valuation method (CVM) to investigate information effects in the valuation of electricity and waterwww.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Information Effects in Valuation of Electricity and Water Service Attributes Using Contingent Valuation EPRG Working Paper 1127 Cambridge Working

  14. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    factors that affect WTP for the attributes considered. Keywords Contingent Valuation Method, Willingnesswww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Information Effects in Valuation of Electricity and Water Service Attributes Using Contingent Valuation EPRG Working Paper 1127 Cambridge Working Paper

  15. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY The Economics of the Nord Stream with the construction of the Yamal-Europe pipeline in the 1990s and continued more recently with the Nord Stream west-European clients. The Nord Stream project has been politically controversial since its inception

  16. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract The Economics of the Nord Stream Pipeline System M. Reiner We calculate the total cost of building Nord Stream and compare its levelised unit cost of shipping through Nord Stream is clearly lower than using the Ukrainian route and is only

  17. Self-induced ac Stark shift in lasers

    SciTech Connect (OSTI)

    Gil, L.; Lippi, G. L. [Universite de Nice Sophia Antipolis, Institut Non Lineaire de Nice, and CNRS, UMR 6618 1361 Route des Lucioles, F-06560 Valbonne (France)

    2011-04-15T23:59:59.000Z

    The ac Stark effect is a well-known, well-established effect associated with the displacement of the atomic energy levels in the presence of an electromagnetic (e.m.) field. As the origin of the e.m. field is irrelevant, a self-induced ac Stark effect should be present in a laser. However, not only has this effect never been reported but it is not included in any laser model. Here, we show that a self-induced ac Stark shift does exist in the theoretical description of a two-level laser, provided that the reduced equations are derived not from the rotating-wave approximation, but from the full density matrix formulation. Interesting fundamental consequences are discussed and quantitative estimates of the self-induced frequency shift resulting from the laser field's ac Stark shift are obtained for a variety of lasers. We find that the effect is generally small but (at least in some cases) measurable and that the transfer of laser amplitude noise into frequency noise may play a role in future, ultrahigh-precision metrological applications.

  18. ACS DIVISION OF POLYMERIC MATERIALS: SCIENCE AND ENGINEERING

    E-Print Network [OSTI]

    Gilchrist, James F.

    , interpenetrating polymer networks, IPNs. Other topics included the mechanical and morphological aspects of polymers textbook, "Introduction to Physical Polymer Science," with Wiley, 2004. While in retirement, he remains for Polymer Science and Engineering, and served as Education Chairman. His efforts at ACS have included

  19. SCHOOL OF ENGINEERING www.abdn.ac.uk/engineering

    E-Print Network [OSTI]

    Levi, Ran

    , in the planning and commissioning of equipment, and in site and plant supervision. Engineers require a wide rangeSCHOOL OF ENGINEERING www.abdn.ac.uk/engineering POSTGRADUATE GUIDE #12;MSc Renewable Energy MSc Safety Engineering for Oil & Gas MSc Subsea Engineering MSc Oil & Gas Engineering MSc Project Management

  20. www.cardiff.ac.uk/ifp International Foundation

    E-Print Network [OSTI]

    Davies, Christopher

    www.cardiff.ac.uk/ifp International Foundation Programme Business, Engineering, Health & Life Sciences #12;Welcome to the International Foundation Programme at Cardiff University What is the IFP? The International Foundation Programme (IFP) is a one-year academic programme designed to give you the academic

  1. 1go.warwick.ac.uk/engineering ENGINEERING

    E-Print Network [OSTI]

    Davies, Christopher

    1go.warwick.ac.uk/engineering 2012-13 ENGINEERING UNDERGRADUATE BROCHURE #12;2 Engineering Prospectus 2012-13 "BECAUSE ENGINEERING IS INEXTRICABLY TIED TO PEOPLE, IT CANNOT BE JUST AN APPLIED PHYSICAL SCIENCE; IT IS ALSO AN APPLIED SOCIAL SCIENCE. ... (THE ENGINEER'S)... RAISON D'?TRE IS TO SERVE

  2. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    de Gispert, Adrià

    . The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise fromwww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Locational-based Coupling of Electricity Markets the effects of varying system characteristics on the magnitude of the locational-based unit commitment

  3. Carbon Nanotube Field-effect Transistors: AC Performance Capabilities.

    E-Print Network [OSTI]

    Pulfrey, David L.

    Carbon Nanotube Field-effect Transistors: AC Performance Capabilities. D.L. Pulfrey, D.L. John-barrier carbon nanotube field-effect transistors are examined via simulations using a self-consistent Schrödinger is known about the DC capabilities of carbon nanotube field-effect transistors [1,2,3], and devices

  4. www.glasgow.ac.uk/library The University Library

    E-Print Network [OSTI]

    Guo, Zaoyang

    www.glasgow.ac.uk/library The University Library for staff #12;www.facebook.com/uofglibrary twitter.com/uofglibrary instagram.com/uoglibrary Library Blog universityofglasgowlibrary.wordpress.com Welcome to the University Library Where is the Library? It's on Hillhead Street, next to the Hunterian Art Gallery, at the heart

  5. POLICY ON CALENDAR SUBMISSIONS University Policy No: AC1120

    E-Print Network [OSTI]

    Victoria, University of

    1 POLICY ON CALENDAR SUBMISSIONS University Policy No: AC1120 Classification: Academic and Students relevant university policies and procedures, academic policies and regulations, university fees, courses and programs of study. The purpose of this policy is to outline requirements for publishing the University

  6. University Policy No.: AC1130 Classification: Academic and Students

    E-Print Network [OSTI]

    Victoria, University of

    University Policy No.: AC1130 Classification: Academic and Students Approving Authority: Board Last Editorial Change: Mandated Review: 2018 PURPOSE 1.00 The purpose of this policy is to provide guidance on the establishment and governance of student awards by the university. POLICY 2.00 Student

  7. ACS WFC CCD Radiation Test: The Radiation Environment

    E-Print Network [OSTI]

    Sirianni, Marco

    of external surfaces by naturally occurring atomic oxygen. CCD detectors are particularly vulnerable to damage damage. A comprehensive discussion of the types of radiation damage known to occur in CCDs is beyond1 ACS WFC CCD Radiation Test: The Radiation Environment Michael R. Jones Space Telescope Science

  8. University Policy No.: AC1110 Classification: Academic and Students

    E-Print Network [OSTI]

    Victoria, University of

    other than the university community. DEFINITIONS 2.00 EDUCATIONAL SERVICE CONTRACT means a contract://web.uvic.ca/univsec/pol_pro/pol1000/1002SA.html) 8.00 Approval of an Educational Service Contract will be granted by the Dean andUniversity Policy No.: AC1110 Classification: Academic and Students EDUCATIONAL SERVICE

  9. 2D 3D * iklee)@yonsei.ac.kr

    E-Print Network [OSTI]

    Lee, In-Kwon

    1 2012 2D 3D * 0 , 1 , 2 0,2 1 ( 0 skrcjstk, 2 iklee)@yonsei.ac.kr 1 rinthel Science, Yonsei University. 1 Dept. of Information Media, The University of Suwon. 2D 3D . 2D - , 3D (Disparity) 3D . . 1. 3D 3D . 3D 3D [1

  10. University Policy No.: AC1135 Classification: Academic and Students

    E-Print Network [OSTI]

    Victoria, University of

    or graduate certificate or diploma program must have a clearly defined educational objective and rationaleUniversity Policy No.: AC1135 Classification: Academic and Students POLICY FOR THE ESTABLISHMENT Approving Authority: Senate OF CERTIFICATE AND DIPLOMA Effective Date: December/07 PROGRAMS Supersedes: May

  11. University Policy No.: AC1200 Classification: Academic and Students

    E-Print Network [OSTI]

    Victoria, University of

    University Policy No.: AC1200 Classification: Academic and Students GUIDELINES ON CONFLICT be no unfair restrictions on the educational and employment opportunities of all students nor, or applying to be enrolled, in a course or program offered by the University for credit towards

  12. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    of the nuclear element of the energy decision process is #12;www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON, energy efficiency, distributed power generation and renewable energy sources. Opponents to nuclear power and Nuclear Power Generation EPRG Working Paper EPRG 0912 John Ash The issue of whether to include nuclear

  13. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Nuclear Energy in the Enlarged with with nuclear energy has also increased markedly in recent years. Two contrasting examples of nuclear experience to concerns for Europe's energy security. As citizens in these countries shift to electric heating

  14. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Nuclear Energy in the Enlarged European Union of nuclear energy and notes that it has shifted significantly as the European Union has grown from 15 member states to 27. The proportion of member states with nuclear energy experience has increased markedly. Also

  15. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    ). There are resource shortages already in the nuclear energy industry, and currently the Supplier to the nuclear in existence. The latter problems pose a risk for the Suppliers to operators in the nuclear energy industrywww.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Third Party Nuclear Liability

  16. FBDEditor: {ldalove, atang34, syjsmk, jbyoo}@konkuk.ac.kr

    E-Print Network [OSTI]

    }@konkuk.ac.kr : Programmable Logic Controller (PLC) . Field Programmable Gate Array (FPGA) . PLC Function Controller (PLC) Field Programmable Gate Array (FPGA) . PLC IEC 61131-3 5 (LD: Ladder diagram) . FBD Function Block(FB) . FBD PLC . FPGA Hardware Description Language

  17. Efficiency Ratings for the Daiken AC (Americas), Inc.

    E-Print Network [OSTI]

    Efficiency Ratings for the Daiken AC (Americas), Inc. Altherma Air-to-Water Source Heat Pump System is used to provide water heating, the EF for that separate water heater shall be used for performance Description Model No. Capacity (tons) Space Heating Space Cooling SEER Water Heating Efficiency

  18. Synchronization of high speed framing camera and intense electron-beam accelerator

    SciTech Connect (OSTI)

    Cheng Xinbing; Liu Jinliang; Hong Zhiqiang; Qian Baoliang [College of Opto-electronic Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)

    2012-06-15T23:59:59.000Z

    A new trigger program is proposed to realize the synchronization of high speed framing camera (HSFC) and intense electron-beam accelerator (IEBA). The trigger program which include light signal acquisition radiated from main switch of IEBA and signal processing circuit could provide a trigger signal with rise time of 17 ns and amplitude of about 5 V. First, the light signal was collected by an avalanche photodiode (APD) module, and the delay time between the output voltage of APD and load voltage of IEBA was tested, it was about 35 ns. Subsequently, the output voltage of APD was processed further by the signal processing circuit to obtain the trigger signal. At last, by combining the trigger program with an IEBA, the trigger program operated stably, and a delay time of 30 ns between the trigger signal of HSFC and output voltage of IEBA was obtained. Meanwhile, when surface flashover occurred at the high density polyethylene sample, the delay time between the trigger signal of HSFC and flashover current was up to 150 ns, which satisfied the need of synchronization of HSFC and IEBA. So the experiment results proved that the trigger program could compensate the time (called compensated time) of the trigger signal processing time and the inherent delay time of the HSFC.

  19. Direct collapse black hole formation from synchronized pairs of atomic cooling halos

    E-Print Network [OSTI]

    Visbal, Eli; Bryan, Greg L

    2014-01-01T23:59:59.000Z

    High-redshift quasar observations imply that supermassive black holes (SMBHs) larger than $\\sim 10^9 ~ M_\\odot$ formed before $z=6$. That such large SMBHs formed so early in the Universe remains an open theoretical problem. One possibility is that gas in atomic cooling halos exposed to strong Lyman-Werner (LW) radiation forms $10^4-10^6 ~ M_\\odot$ supermassive stars which quickly collapse into black holes. We propose a scenario for direct collapse black hole (DCBH) formation based on synchronized pairs of pristine atomic cooling halos. We consider halos at very small separation with one halo being a subhalo of the other. The first halo to surpass the atomic cooling threshold forms stars. Soon after these stars are formed, the other halo reaches the cooling threshold and due to its small distance from the newly formed galaxy, is exposed to the critical LW intensity required to form a DCBH. The main advantage of this scenario is that synchronization can potentially prevent photoevaporation and metal pollution i...

  20. Permanent magnet steam generator

    SciTech Connect (OSTI)

    Gerard, F.; Gerard, F.J.

    1986-09-30T23:59:59.000Z

    This patent describes a system for magnetic heating of a fluid by motor rotation of a permanent magnet rotor adjacent an assembly of ferro-magnetic condensing plate and of copper heat absorber plate with protrusions through the ferro-magnetic condensing plate into an enclosure with the fluid therein and having fluid inlet and fluid outlet. The assembly has a first shaft and a second shaft coaxially spaced therefrom, a respective the motor connected to the outer end of each shaft, and a respective the permanent magnet rotor connected to the inner end of each shaft, adjacent a the heat absorber plate. The improvement described here comprises: the enclosure including a steel boiler with a first the ferro-magnetic condensing plate closing off a first end thereof and a second the ferro-magnetic condensing plate closing off a second end thereof, a the copper heat absorbing plate affixed on each ferro-magnetic plate; means, free of pockets, for promoting turbulent flow of the fluid with uniformly good heat transfer including the protrusion being a plurality of heat sinks, each heat sink of the plurality of heat sinks comprising an integral elongate member with an alternately large diameter and smaller diameter portions regularly spaced therealong. The elongate members through the first the ferro-magnetic condensing plate are coaxially aligned with the elongate members through the second the ferro-magnetic condensing plate.

  1. Sensorless Direct Torque Control For Salient Pole PMSM Based on Extended Kalman Filter Fed By AC/DC/AC Converter

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Sensorless Direct Torque Control For Salient ­ Pole PMSM Based on Extended Kalman Filter Fed By AC is proposed. The Direct Torque Control (DTC) technique for PMSM is receiving increasing attention due on the stochastic intromission, in others words, noise. The PMSM is fed by an indirect power electronic converter

  2. Passive magnetic bearing system

    DOE Patents [OSTI]

    Post, Richard F.

    2014-09-02T23:59:59.000Z

    An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

  3. Pulse magnetic welder

    DOE Patents [OSTI]

    Christiansen, D.W.; Brown, W.F.

    1984-01-01T23:59:59.000Z

    A welder is described for automated closure of fuel pins by a pulsed magnetic process in which the open end of a length of cladding is positioned within a complementary tube surrounded by a pulsed magnetic welder. Seals are provided at each end of the tube, which can be evacuated or can receive tag gas for direct introduction to the cladding interior. Loading of magnetic rings and end caps is accomplished automatically in conjunction with the welding steps carried out within the tube.

  4. Magnetic Braids Anthony Yeates

    E-Print Network [OSTI]

    Dundee, University of

    flux function Main result Conclusion 2. Thermonuclear confinement devices. ITER (Internat'l Thermonuclear Experimental Reactor). Inside the KSTAR tokamak. Correspond to periodic magnetic braids. 4 / 22

  5. Magnetic differential torque sensor

    SciTech Connect (OSTI)

    Lemarquand, V.; Lemarquand, G. [Univ. de Savoie, Annecy-le-Vieux (France)] [Univ. de Savoie, Annecy-le-Vieux (France)

    1995-11-01T23:59:59.000Z

    A new torque sensor structure is presented. The basic idea is a simple torque sensor with a variable magnetic circuit excited by an axially magnetized permanent magnet ring. The circuit is constituted by iron toothed rings, whose teeth relative position changes whenever an applied torque twists the rotating shaft. A Hall probe measures the induction in an airgap where the induction is uniform. The new structure is an association of two previous ones, thus creating a differential system with the related advantages: diminution of thermal drifts, zero mean value for the signal. The new magnetic circuit is studied by calculating equivalent reluctances through energy calculations and by using electrical analogies.

  6. Tel: +44 (0) 1603 591574 Email: business@uea.ac.uk Web: www.uea.ac.uk/business Experts model buyer behaviour

    E-Print Network [OSTI]

    Everest, Graham R

    Tel: +44 (0) 1603 591574 Email: business@uea.ac.uk Web: www.uea.ac.uk/business Experts model buyer their customers to make buying decisions. When you are in the business of printing newspapers, accurate ­ the UK's largest independently-owned regional media business ­ on a project which saw academics from

  7. Abstract--This paper presents a comparative stability analysis of conventional synchronous generators and wind farms based on

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    the wind turbines are operated with terminal voltage control. Index Terms-- Power system stability, Wind power generation, Synchronous generators. I. INTRODUCTION OWDAYS, wind power energy is increasingly advantages such as the decoupled control of active and reactive powers and maximum power tracking

  8. International Journal of Wireless Mobile Networks (IJWMN), Vol.2, No.2, May 2010 Energy Efficient Global Clock Synchronization

    E-Print Network [OSTI]

    Namboodiri, Vinod

    synchronization in the most energy-efficient manner possible. We look at the problem through two dimensions; rate evaluation demonstrates that the power assignment derived from this algorithm is very energy-efficient a simple distributed algorithm which nodes can execute locally to derive energy-efficient power levels

  9. Detecting Generalized Synchronization of Chaotic Dynamical Systems: A Kernel-based Method and Choice of Its Parameter

    E-Print Network [OSTI]

    Hiromichi Suetani; Yukito Iba; Kazuyuki Aihara

    2005-07-21T23:59:59.000Z

    An approach based on the kernel methods for capturing the nonlinear interdependence between two signals is introduced. It is demonstrated that the proposed approach is useful for characterizing generalized synchronization with a successful simple example. An attempt to choose an optimal kernel parameter based on cross validation is also discussed.

  10. Abstract--This paper investigates the effect of STATCOM in stabilising multi-mode torsional oscillations of sub-synchronous

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    oscillations of sub-synchronous resonance (SSR) of a large turbine-generator set. The study is performed oscillating frequencies of the turbine generator mass-spring system, the SSR will develop. The electric generator set will be mutually excited causing serious shaft oscillations and other damages to the system

  11. Flux-Weakening Strategies for a Five-Phase PM Synchronous Machine Li Lu(1)(2)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    (Five-Phase PMSM), Maximum Torque Per Ampere(MTPA), base speed, back-EMF I. Model of a Five-Phase PM Synchronous Machine(Five-Phase PMSM) In order to deduce a control structure for a five-phase machine, a modelling

  12. Booster main magnet power supply, present operation and potential future upgrades

    SciTech Connect (OSTI)

    Bajon, E.; Bannon, M.; Marneris, I.; Danowski, G.; Sandberg, J.; Savatteri, S.

    2011-03-28T23:59:59.000Z

    The Brookhaven Booster Main Magnet Power Supply (MMPS) is a 24 pulse thyristor control supply, rated at 5500 Amps, +/-2000 Volts, or 3000 Amps, +/-6000 Volts. The power supply is fed directly from the power utility and the peak magnet power is 18 MWatts. This peak power is seen directly at the incoming ac line. This power supply has been in operation for the last 18 years. This paper will describe the present topology and operation of the power supply, the feedback control system and the different modes of operation of the power supply. Since the power supply has been in operation for the last 18 years, upgrading this power supply is essential. A new power supply topology has been studied where energy is stored in capacitor banks. DC to DC converters are used to convert the dc voltage stored in the capacitor banks to pulsed DC voltage into the magnet load. This enables the average incoming power from the ac line to be constant while the peak magnet power is pulsed to +/- 18 MWatts. Simulations and waveforms of this power supply will be presented.

  13. Couples Magnetic and Structural Transitions in High-Purity Dy and Gd5SbxGe4-x

    SciTech Connect (OSTI)

    Alexander S. Chernyshov

    2006-08-09T23:59:59.000Z

    Magnetic materials exhibiting magnetic phase transitions simultaneously with structural rearrangements of their crystal lattices hold a promise for numerous applications including magnetic refrigeration, magnetomechanical devices and sensors. We undertook a detailed study of a single crystal of dysprosium metal, which is a classical example of a system where magnetic and crystallographic sublattices can be either coupled or decoupled from one another. Magnetocaloric effect, magnetization, ac magnetic susceptibility, and heat capacity of high purity single crystals of dysprosium have been investigated over broad temperature and magnetic field intervals with the magnetic field vector parallel to either the a- or c-axes of the crystal. Notable differences in the behavior of the physical properties when compared to Dy samples studied in the past have been observed between 110 K and 125 K, and between 178 K and {approx}210 K. A plausible mechanism based on the formation of antiferromagnetic clusters in the impure Dy has been suggested in order to explain the reduction of the magnetocaloric effect in the vicinity of the Neel point. Experimental and theoretical investigations of the influence of commensurability effects on the magnetic phase diagram and the value of the magnetocaloric effect have been conducted. The presence of newly found anomalies in the physical properties has been considered as evidence of previously unreported states of Dy. The refined magnetic phase diagram of dysprosium with the magnetic field vector parallel to the a-axis of a crystal has been constructed and discussed. The magnetic and crystallographic properties of Gd{sub 5}Sb{sub x}Ge{sub 4-x} pseudo-binary system were studied by x-ray diffraction (at room temperature), heat capacity, ac-magnetic susceptibility, and magnetization in the temperature interval 5-320 K in magnetic fields up to 100 kOe. The magnetic properties of three composition (x = 0.5, 1,2) were examined in detail. The Gd{sub 5}Sb{sub 2}Ge{sub 2} compound that adopts Tm{sub 5}Sb{sub 2}Si{sub 2}-type of structure (space group is Cmca), shows a second order FM-PM transition at 200 K, whereas Gd{sub 5}Sb{sub x}Ge{sub 4-x} compounds for x = 0.5 and x = 1 (Sm{sub 5}Ge{sub 4}-type of structure, space group is Pnma) exhibit first order phase transformations at 45 K and 37 K, respectively.

  14. SNL software manual for the ACS Data Analytics Project.

    SciTech Connect (OSTI)

    Stearley, Jon R.; McLendon, William Clarence, III; Rodrigues, Arun F.; Williams, Aaron S.; Hooper, Russell Warren; Robinson, David Gerald; Stickland, Michael G.

    2011-10-01T23:59:59.000Z

    In the ACS Data Analytics Project (also known as 'YumYum'), a supercomputer is modeled as a graph of components and dependencies, jobs and faults are simulated, and component fault rates are estimated using the graph structure and job pass/fail outcomes. This report documents the successful completion of all SNL deliverables and tasks, describes the software written by SNL for the project, and presents the data it generates. Readers should understand what the software tools are, how they fit together, and how to use them to reproduce the presented data and additional experiments as desired. The SNL YumYum tools provide the novel simulation and inference capabilities desired by ACS. SNL also developed and implemented a new algorithm, which provides faster estimates, at finer component granularity, on arbitrary directed acyclic graphs.

  15. Pulsed Plasma with Synchronous Boundary Voltage for Rapid Atomic Layer Etching

    SciTech Connect (OSTI)

    Economou, Demetre J.; Donnelly, Vincent M.

    2014-05-13T23:59:59.000Z

    Atomic Layer ETching (ALET) of a solid with monolayer precision is a critical requirement for advancing nanoscience and nanotechnology. Current plasma etching techniques do not have the level of control or damage-free nature that is needed for patterning delicate sub-20 nm structures. In addition, conventional ALET, based on pulsed gases with long reactant adsorption and purging steps, is very slow. In this work, novel pulsed plasma methods with synchronous substrate and/or boundary electrode bias were developed for highly selective, rapid ALET. Pulsed plasma and tailored bias voltage waveforms provided controlled ion energy and narrow energy spread, which are critical for highly selective and damage-free etching. The broad goal of the project was to investigate the plasma science and engineering that will lead to rapid ALET with monolayer precision. A combined experimental-simulation study was employed to achieve this goal.

  16. A digital excitation control system for use on brushless excited synchronous generators

    SciTech Connect (OSTI)

    Godhwani, A. [Southern Illinois Univ., Edwardsville, IL (United States)] [Southern Illinois Univ., Edwardsville, IL (United States); Basler, M.J. [Basler Electric Co., Highland, IL (United States)] [Basler Electric Co., Highland, IL (United States)

    1996-09-01T23:59:59.000Z

    Automatic voltage regulators for small to medium size brushless excited synchronous generators have traditionally utilized analog electronics. Modern voltage regulator systems are beginning to utilize the power, flexibility, and cost advantage of the microprocessor for control. Furthermore, digital voltage regulators have the added advantage of ease of compensator custom-design. This paper presents a new method for determining the stability parameters for small/medium size generators that have limited effect on overall system stability. A Digital Excitation Control System (DECS) is used as a platform for this discussion. DECS utilizes a discrete Proportional, Integral and Derivative (PID) control algorithm. A direct design (Pole Placement) method for selecting PID parameters is presented along with the test results.

  17. A Self-Organizing Neural Network for Contour Integration through Synchronized Firing

    E-Print Network [OSTI]

    2000-01-01T23:59:59.000Z

    Contour integration in low-level vision is believed to occur based on lateral interaction between neurons with similar orientation tuning. The exact neural mechanisms underlying such interactions, and their developmental origins, are not well understood. This paper suggests through computational simulations that synchronized firing of neurons mediated by patchy lateral connections, formed through input-driven selforganization, can serve as such a mechanism. Furthermore, we argue that different degree of such patchy connections established during development may explain why different areas of the visual field show different degrees of contour integration in psychophysical experiments. Introduction Contour integration in low-level vision means forming a single coherent percept (i.e. a continuous contour) from a discontinuous sequence of line segments. Humans are very good at contour integration; understanding the underlying mechanisms can give us insights into how perceptual...

  18. Reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application

    DOE Patents [OSTI]

    Archer, Charles J. (Rochester, MN); Blocksome, Michael A. (Rochester, MN); Peters, Amanda A. (Rochester, MN); Ratterman, Joseph D. (Rochester, MN); Smith, Brian E. (Rochester, MN)

    2012-01-10T23:59:59.000Z

    Methods, apparatus, and products are disclosed for reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application that include: beginning, by each compute node, performance of a blocking operation specified by the parallel application, each compute node beginning the blocking operation asynchronously with respect to the other compute nodes; reducing, for each compute node, power to one or more hardware components of that compute node in response to that compute node beginning the performance of the blocking operation; and restoring, for each compute node, the power to the hardware components having power reduced in response to all of the compute nodes beginning the performance of the blocking operation.

  19. Reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application

    DOE Patents [OSTI]

    Archer, Charles J. (Rochester, MN); Blocksome, Michael A. (Rochester, MN); Peters, Amanda E. (Cambridge, MA); Ratterman, Joseph D. (Rochester, MN); Smith, Brian E. (Rochester, MN)

    2012-04-17T23:59:59.000Z

    Methods, apparatus, and products are disclosed for reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application that include: beginning, by each compute node, performance of a blocking operation specified by the parallel application, each compute node beginning the blocking operation asynchronously with respect to the other compute nodes; reducing, for each compute node, power to one or more hardware components of that compute node in response to that compute node beginning the performance of the blocking operation; and restoring, for each compute node, the power to the hardware components having power reduced in response to all of the compute nodes beginning the performance of the blocking operation.

  20. Synchronous digitization for high dynamic range lock-in amplification in beam-scanning microscopy

    SciTech Connect (OSTI)

    Muir, Ryan D.; Sullivan, Shane Z.; Oglesbee, Robert A.; Simpson, Garth J., E-mail: gsimpson@purdue.edu [Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907 (United States)

    2014-03-15T23:59:59.000Z

    Digital lock-in amplification (LIA) with synchronous digitization (SD) is shown to provide significant signal to noise (S/N) and linear dynamic range advantages in beam-scanning microscopy measurements using pulsed laser sources. Direct comparisons between SD-LIA and conventional LIA in homodyne second harmonic generation measurements resulted in S/N enhancements consistent with theoretical models. SD-LIA provided notably larger S/N enhancements in the limit of low light intensities, through the smooth transition between photon counting and signal averaging developed in previous work. Rapid beam scanning instrumentation with up to video rate acquisition speeds minimized photo-induced sample damage. The corresponding increased allowance for higher laser power without sample damage is advantageous for increasing the observed signal content.