National Library of Energy BETA

Sample records for ac variable frequency

  1. Variable Frequency Pump Drives 

    E-Print Network [OSTI]

    Karassik, I. J.; Petraccaro, L. L.; McGuire, J. T.

    1986-01-01

    variable flow operation, Fig. 2 variable system head, the objective of the latter being to maintain pump flow within an optimum range while accommodating a wide variation in system head. VARYING OPERATING CAPACITY OPERATING CAPACITY? N, RANGE HEAD...-rotor motors and variable speed devices have slip losses that significantly reduce the savings that accrue by operating pumps at variable speed. Steam turbine drives may not always be the most practical or economic solution. The variable frequency...

  2. Variable frequency photonic crystals

    E-Print Network [OSTI]

    Wu, Xiang-Yao; Liu, Xiao-Jing; Yang, Jing-Hai; Li, Hong; Chen, Wan-Jin

    2015-01-01

    In this paper, we have firstly proposed a new one-dimensional variable frequency photonic crystals (VFPCs), and calculated the transmissivity and the electronic field distribution of VFPCs with and without defect layer, and considered the effect of defect layer and variable frequency function on the transmissivity and the electronic field distribution. We have obtained some new characteristics for the VFPCs, which should be help to design a new type optical devices.

  3. High frequency AC power converter for low voltage circuits

    E-Print Network [OSTI]

    Salazar, Nathaniel Jay Tobias

    2012-01-01

    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. Low frequency AC waveform generator

    DOE Patents [OSTI]

    Bilharz, Oscar W. (Scotia, NY)

    1986-01-01

    Low frequency sine, cosine, triangle and square waves are synthesized in circuitry which allows variation in the waveform amplitude and frequency while exhibiting good stability and without requiring significant stabilization time. A triangle waveform is formed by a ramped integration process controlled by a saturation amplifier circuit which produces the necessary hysteresis for the triangle waveform. The output of the saturation circuit is tapped to produce the square waveform. The sine waveform is synthesized by taking the absolute value of the triangular waveform, raising this absolute value to a predetermined power, multiplying the raised absolute value of the triangle wave with the triangle wave itself and properly scaling the resultant waveform and subtracting it from the triangular waveform itself. The cosine is synthesized by squaring the triangular waveform, raising the triangular waveform to a predetermined power and adding the squared waveform raised to the predetermined power with a DC reference and subtracting the squared waveform therefrom, with all waveforms properly scaled. The resultant waveform is then multiplied with a square wave in order to correct the polarity and produce the resultant cosine waveform.

  5. Variable frequency microwave heating apparatus

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN); Johnson, Arvid C. (Lake in the Hills, IL); Thigpen, Larry T. (Angier, NC)

    1999-01-01

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity (34) for testing or other selected applications. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a high-power microwave oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  6. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, D.W.; Lauf, R.J.

    1994-06-14

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  7. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  8. Aalborg Universitet Cooperative Frequency Control for Autonomous AC Microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Cooperative Frequency Control for Autonomous AC Microgrids Shafiee, Qobad, J. C. V., & Guerrero, J. M. (2015). Cooperative Frequency Control for Autonomous AC Microgrids.aau.dk on: november 29, 2015 #12;This document downloaded from www.microgrids.et.aau.dk is the preprint

  9. Solid State AC Motor Drives - Conservation Perspectives 

    E-Print Network [OSTI]

    Mohan, N.; Ferraro, R. J.

    1982-01-01

    Variable Frequency Solid-State Inverters: can control the speed of ac motors by producing adjustable frequency ac voltage, with an enormous potential for energy conservation in pumps and air handling systems. 3. Other Variable Frequency Drives: include...

  10. Soft switched high frequency ac-link converter 

    E-Print Network [OSTI]

    Balakrishnan, Anand Kumar

    2009-05-15

    Variable frequency drives typically have employed dc voltage or current links for power distribution between the input and output converters and as a means to temporarily store energy. The dc link based power conversion systems have several inherent...

  11. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-08-25

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  12. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-09-08

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  13. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)

    1998-01-01

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

  14. Chapter 18: Variable Frequency Drive Evaluation Protocol

    SciTech Connect (OSTI)

    Romberger, J.

    2014-11-01

    An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol. Other ASD devices, such as magnetic drive, eddy current drives, variable belt sheave drives, or direct current motor variable voltage drives, are also not addressed. The VFD is by far the most common type of ASD hardware. With VFD speed control on a centrifugal fan or pump motor, energy use follows the affinity laws, which state that the motor electricity demand is a cubic relationship to speed under ideal conditions. Therefore, if the motor runs at 75% speed, the motor demand will ideally be reduced to 42% of full load power; however, with other losses it is about 49% of full load power.

  15. Fault-tolerant Partial-resonant High-frequency AC-link Converters and Their Applications 

    E-Print Network [OSTI]

    Keyhani, Hamidreza

    2014-01-08

    in the converter shutdown, and thus system availability is improved. The high-frequency ac link of the introduced converters is composed of an ac inductor and small ac capacitor. The link inductor is responsible for transferring power, while the link capacitor...

  16. System for transmitting low frequency analog signals over AC power lines

    DOE Patents [OSTI]

    Baker, Steven P. (Powell, TN); Durall, Robert L. (Lenoir City, TN); Haynes, Howard D. (Knoxville, TN)

    1989-01-01

    A system for transmitting low frequency analog signals over AC power lines using FM modulation. A low frequency analog signal to be transmitted is first applied to a voltage-to-frequency converter where it is converted to a signal whose frequency varies in proportion to the analog signal amplitude. This signal is then used to modulate the carrier frequency of an FM transmitter coupled to an AC power line. The modulation signal frequency range in selected to be within the response band of the FM transmitter. The FM modulated carrier signal is received by an FM receiver coupled to the AC power line, demodulated and the demodulated signal frequency is converted by a frequency-to-voltage converter back to the form of the original low frequency analog input signal.

  17. A system for tranmitting low frequency analog signals over ac power lines

    DOE Patents [OSTI]

    Baker, S.P.; Durall, R.L.; Haynes, H.D.

    1987-07-30

    A system for transmitting low frequency analog signals over ac power lines using FM modulation. A low frequency analog signal to be transmitted is first applied to a voltage-to-frequency converter where it is converted to a signal whose frequency varies in proportion to the analog signal amplitude. This signal is then used to modulate the carrier frequency of an FM transmitter coupled to an ac power line. The modulation signal frequency range is selected to be within the response band of the FM transmitter. The FM modulated carrier signal is received by an FM receiver coupled to the ac power line, demodulated and the demodulated signal frequency is converted by a frequency-to-voltage converter back to the form of the original low frequency analog input signal. 4 figs.

  18. Wind spatial variability and topographic wave frequency Elad Shilo*1

    E-Print Network [OSTI]

    Ashkenazy, Yossi "Yosef"

    Wind spatial variability and topographic wave frequency Elad Shilo*1 , Yosef Ashkenazy2 , Alon of topographic waves with wind action has been documented in several natural lakes throughout the world. However, the influence of the wind's spatial variability (wind stress curl) on the frequency of topographic waves has

  19. Present and Future Modes of Low Frequency Climate Variability

    SciTech Connect (OSTI)

    Cane, Mark A.

    2014-02-20

    This project addressed area (1) of the FOA, “Interaction of Climate Change and Low Frequency Modes of Natural Climate Variability”. Our overarching objective is to detect, describe and understand the changes in low frequency variability between model simulations of the preindustrial climate and simulations of a doubled CO2 climate. The deliverables are a set of papers providing a dynamical characterization of interannual, decadal, and multidecadal variability in coupled models with attention to the changes in this low frequency variability between pre-industrial concentrations of greenhouse gases and a doubling of atmospheric concentrations of CO2. The principle mode of analysis, singular vector decomposition, is designed to advance our physical, mechanistic understanding. This study will include external natural variability due to solar and volcanic aerosol variations as well as variability internal to the climate system. An important byproduct is a set of analysis tools for estimating global singular vector structures from the archived output of model simulations.

  20. Variable Frequency Drives: Energy Savings and Impact on Motor Performance 

    E-Print Network [OSTI]

    Petro, D.

    1993-01-01

    Variable frequency drives (VFDs) have found widespread application in recent years. VFDs are valued for their potential to save energy and improve processes. Reliability has improved significantly, but there are still pitfalls to be addressed...

  1. Variable Frequency AC Drives for Cooling Tower Energy Efficiency 

    E-Print Network [OSTI]

    Corey, R. W.

    1982-01-01

    speed and AF drive conversion to adjustable speed. ~I.,.. '~'Fixed r--'T'~Speed ,_0t.11T ~ ! AUTO ~uAL Figure 3 - Fixed &~djustable Speed sJstems I The AF control .unit is placed in the user's motor control center or inl a weather protected..., this ov~r simplified analysis does put this project in a very likely position for budget approval by the Texas Company p~ant management. 5.0 SUMMARY Traditionally, capita~ expense for eqUipment has been submitted for management approval...

  2. Trapping and Frequency Variability in Electron Acoustic Waves

    E-Print Network [OSTI]

    California at San Diego, University of

    Trapping and Frequency Variability in Electron Acoustic Waves C.F. Driscoll, F. Anderegg, D 92093 USA Abstract. Electron Acoustic Waves (EAWs) with a phase velocity less than twice the plasma. Keywords: add some here PACS: 52.27.Jt, 52.35.Fp, 52.35.Sb Electron Acoustic Waves (EAWs) are the low

  3. Observation of multi-scale oscillation of laminar lifted flames with low-frequency AC electric fields

    SciTech Connect (OSTI)

    Ryu, S.K.; Kim, Y.K.; Kim, M.K.; Won, S.H. [School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742 (Korea); Chung, S.H. [Clean Combustion Research Center, King Abdullah University of Science and Technology, Thuwal (Saudi Arabia)

    2010-01-15

    The oscillation behavior of laminar lifted flames under the influence of low-frequency AC has been investigated experimentally in coflow jets. Various oscillation modes were existed depending on jet velocity and the voltage and frequency of AC, especially when the AC frequency was typically smaller than 30 Hz. Three different oscillation modes were observed: (1) large-scale oscillation with the oscillation frequency of about 0.1 Hz, which was independent of the applied AC frequency, (2) small-scale oscillation synchronized to the applied AC frequency, and (3) doubly-periodic oscillation with small-scale oscillation embedded in large-scale oscillation. As the AC frequency decreased from 30 Hz, the oscillation modes were in the order of the large-scale oscillation, doubly-periodic oscillation, and small-scale oscillation. The onset of the oscillation for the AC frequency smaller than 30 Hz was in close agreement with the delay time scale for the ionic wind effect to occur, that is, the collision response time. Frequency-doubling behavior for the small-scale oscillation has also been observed. Possible mechanisms for the large-scale oscillation and the frequency-doubling behavior have been discussed, although the detailed understanding of the underlying mechanisms will be a future study. (author)

  4. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, R.J.; Bible, D.W.; Paulauskas, F.L.

    1998-02-24

    A method for curing polymers incorporating a variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity is disclosed. By varying the frequency of the microwave signal, non-uniformities within the cavity are minimized, thereby achieving a more uniform cure throughout the workpiece. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. The furnace cavity may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing. 15 figs.

  5. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); Bible, Don W. (Clinton, TN); Paulauskas, Felix L. (Oak Ridge, TN)

    1998-01-01

    A method for curing polymers (11) incorporating a variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34). By varying the frequency of the microwave signal, non-uniformities within the cavity (34) are minimized, thereby achieving a more uniform cure throughout the workpiece (36). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. The furnace cavity (34) may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing.

  6. Detection of variable frequency signals using a fast chirp transform

    E-Print Network [OSTI]

    F. A. Jenet; T. A. Prince

    2000-12-07

    The detection of signals with varying frequency is important in many areas of physics and astrophysics. The current work was motivated by a desire to detect gravitational waves from the binary inspiral of neutron stars and black holes, a topic of significant interest for the new generation of interferometric gravitational wave detectors such as LIGO. However, this work has significant generality beyond gravitational wave signal detection. We define a Fast Chirp Transform (FCT) analogous to the Fast Fourier Transform (FFT). Use of the FCT provides a simple and powerful formalism for detection of signals with variable frequency just as Fourier transform techniques provide a formalism for the detection of signals of constant frequency. In particular, use of the FCT can alleviate the requirement of generating complicated families of filter functions typically required in the conventional matched filtering process. We briefly discuss the application of the FCT to several signal detection problems of current interest.

  7. Simulation of state-dependent high-frequency atmospheric variability associated with ENSO

    E-Print Network [OSTI]

    Kang, In-Sik

    Simulation of state-dependent high-frequency atmospheric variability associated with ENSO Jong Abstract High-frequency atmospheric variability depends on the phase of El Nino/Southern Oscillation (ENSO). Recently, there is increasing evidence that state- dependent high-frequency atmospheric variability signifi

  8. STFC Introductory Summer School m.j.owens@reading.ac.uk18 Sept 2012 Solar Variability and

    E-Print Network [OSTI]

    · The climate system · Solar variability · Solar effects on climate ­ Regional and global effects · The futureSTFC Introductory Summer School m.j.owens@reading.ac.uk18 Sept 2012 Solar Variability and Climate in our Sun must cause changes in our climate · But we need to consider (a) The potential for changing

  9. Low frequency variability of Southern Ocean jets Andrew F. Thompson1,2

    E-Print Network [OSTI]

    Thompson, Andrew

    Low frequency variability of Southern Ocean jets Andrew F. Thompson1,2 and Kelvin J. Richards3 is concentrated in a large number (approximately 8 to 12) of narrow filamentary jets. It is shown here that coherent jets exhibit a range of low frequency variability, on timescales of months to years, that can lead

  10. Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems 

    E-Print Network [OSTI]

    Han, Xu

    2012-02-14

    Induction motors and Variable Frequency Drives (VFDs) are widely used in industry to drive machinery trains. However, some mechanical trains driven by VFD-motor systems have encountered torsional vibration problems. This vibration can induce large...

  11. High Frequency Effects of Variable Frequency Drives (VFD) on Electrical Submersible Pump (ESP) Systems 

    E-Print Network [OSTI]

    Ozkentli, Esra

    2012-10-19

    is on the system with a VFD controlled motor through a long umbilical cable. A 36-pulse VFD is studied. Since multilevel VFDs have high frequency harmonics, high frequency modeling of the umbilical cable is used, and skin effect is also taken into consideration...

  12. A study of wind variability in the lower troposphere through power spectrum analysis at mesoscale frequencies 

    E-Print Network [OSTI]

    Cornett, John Sheldon

    1966-01-01

    A STUDY OF WIND VARIABILITY IN THE LOWER TROPOSPHERE THROUGH POWER SPECTRUM ANALYSIS AT MESOSCALE FREQUENCIES A Thesis By JOHN SHELDON CORNETT Submitted to the Graduate College of the Texas A&M University in Partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE January 1966 Major Subject: Meteorology A STUDY OP WIND VARIABILITY IN THE LOWER TROPOSPHERE THROUGH POWER SPECTRUM ANALYSIS AT MESOSCALE FREQUENCIES A Thesis By JOHN SHELDON CORNETT Approved as to style...

  13. Conserving Energy in Blast Freezers Using Variable Frequency Drives 

    E-Print Network [OSTI]

    Kolbe, E.; Ling, Q.; Wheeler, G.

    2004-01-01

    ,280 cfm. This might fall by 25% in a fully loaded room. Fan motors were nominal 7-1/2 HP inverter-duty models manufactured by Baldor. Refrigeration System An engine roo m dedicated to freezing operations had a total capacity intended to meet... Baldor Model ID15H430-EO, rated for a 40 HP variable torque load. Other significant components were: - The enclosure; - A ?choke? or line reactor on the incoming line to the VFD. This serves two purposes: it protects the VFD electronics from...

  14. New AC-DC Power Factor Correction Architecture Suitable for High Frequency Operation

    E-Print Network [OSTI]

    Lim, Seungbum

    This paper presents a novel ac-dc power factor correction (PFC) power conversion architecture for single-phase grid interface. The proposed architecture has significant advantages for achieving high efficiency, good power ...

  15. Continuous-Variable Quantum Computing in Optical Time-Frequency Modes using Quantum Memories

    E-Print Network [OSTI]

    Peter C. Humphreys; W. Steven Kolthammer; Joshua Nunn; Marco Barbieri; Animesh Datta; Ian A. Walmsley

    2014-11-21

    We develop a scheme for time-frequency encoded continuous-variable cluster-state quantum computing using quantum memories. In particular, we propose a method to produce, manipulate and measure 2D cluster states in a single spatial mode by exploiting the intrinsic time-frequency selectivity of Raman quantum memories. Time-frequency encoding enables the scheme to be extremely compact, requiring a number of memories that is a linear function of only the number of different frequencies in which the computational state is encoded, independent of its temporal duration. We therefore show that quantum memories can be a powerful component for scalable photonic quantum information processing architectures.

  16. Low-frequency variability of the North Pacific Ocean: The roles of boundary-and wind-driven

    E-Print Network [OSTI]

    Qiu, Bo

    Low-frequency variability of the North Pacific Ocean: The roles of boundary- and wind in determining the low-frequency large-scale variability of the ocean interior through Rossby waves generated. The variability in the ocean interior is primarily driven by wind with only a minor influence from the boundary

  17. Bi-directional Current-fed Medium Frequency Transformer Isolated AC-DC Converter 

    E-Print Network [OSTI]

    Essakiappan, Somasundaram

    2011-08-08

    demand for power converters with bi-directional capabilities. The objective of this thesis is to develop a high power quality, bi-directional AC-DC power converter that is a solution to the aforementioned problems. This thesis studies an existing topology...

  18. A direct AC-to-DC converter topology with high-frequency isolation 

    E-Print Network [OSTI]

    Sulistyono, Widodo

    1994-01-01

    disadvantages of the conventional approach are: it requires relatively large input ac filter components, requires two stages of rectification and of de filtering (i.e., at the front-end and output rectifiers), and exhibit poor overall input power factor...

  19. Low-salinity pools at Barbados, West Indies: Their origin, frequency, and variability

    E-Print Network [OSTI]

    1 Low-salinity pools at Barbados, West Indies: Their origin, frequency, and variability Peter S-temperature recorders moored off the west coast of Barbados, West Indies, from May 1996 to November 1997 revealed radium 228/226 activity ratios of ~1, consistent with previous measurements in Barbados of water

  20. Observed low frequency variability of the Brazil Current front Gustavo Jorge Goni,1

    E-Print Network [OSTI]

    of the Brazil Current front. Trends of eddy kinetic energy, sea height anomaly, sea surface temperature and windObserved low frequency variability of the Brazil Current front Gustavo Jorge Goni,1 Francis Bringas; published 29 October 2011. [1] The Brazil Current is a weak western boundary current, the southwest

  1. [A variable frequency microwave furnace]. CRADA final report for CRADA Number ORNL91-0055

    SciTech Connect (OSTI)

    Lauf, R.J.

    1994-12-08

    The goals of this CRADA were to: (1) development and demonstrate a highly frequency-agile microwave furnace; (2) explore applications of the furnace for materials processing; and (3) develop control systems and packaging that are robust, user-friendly, and suitable for sale as a turnkey system. Microwave Laboratories, Inc. (MLI) designed, built, and successfully brought to market a benchtop Variable Frequency Microwave Furnace (VFMF). The concept has demonstrated advantages in polymer curing, waste remediation, and diamond (CVD). Through experimentation and modeling, the VFMF approach has gained credibility within the technical community.

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

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07

    be used in a variety of applications, including photovoltaic power generation, wind power generation, and electric vehicles. In these converters the link current and voltage are both alternating and their frequency can be high, which leads...

  3. Wind Spatial Variability and Topographic Wave Frequency Department of Soil and Water Sciences, Hebrew University of Jerusalem, Rehovot, Israel

    E-Print Network [OSTI]

    Ashkenazy, Yossi "Yosef"

    Wind Spatial Variability and Topographic Wave Frequency ELAD SHILO Department of Soil and Water of topographic waves with wind action has been documented in several natural lakes throughout the world. However, the influence of the wind's spatial variability (wind stress curl) on the frequency of topographic waves has

  4. T Tauri variability in the context of the beat-frequency model

    E-Print Network [OSTI]

    K. W. Smith; G. F. Lewis; I. A. Bonnell

    1995-08-17

    We examine the implications of a beat frequency modulated model of T Tauri accretion. In particular we show that measurements of the variability of accretion generated lines can be used in conjunction with existing photometry to obtain a measurement of the underlying photospheric and disc flux. This provides an independent way of checking spectral energy distribution modelling. In addition, we show how spectroscopy of T Tauri stars can reveal the inclination angle between the magnetic axis and the plane of the disc.

  5. Running time variability and resource allocation : a data-driven analysis of high-frequency bus operations

    E-Print Network [OSTI]

    Sánchez-Martínez, Gabriel Eduardo

    2013-01-01

    Running time variability is one of the most important factors determining service quality and operating cost of high-frequency bus transit. This research aims to improve performance analysis tools currently used in the bus ...

  6. Variable Frequency Operations of an Offshore Wind Power Plant with HVDC-VSC: Preprint

    SciTech Connect (OSTI)

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

    2011-12-01

    In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated. Based on DOE study, wind power generation may reach 330 GW by 2030 at the level of penetration of 20% of the total energy production. From this amount of wind power, 54 GW of wind power will be generated at offshore wind power plants. The deployment of offshore wind power plants requires power transmission from the plant to the load center inland. Since this power transmission requires submarine cable, there is a need to use High-Voltage Direct Current (HVDC) transmission. Otherwise, if the power is transmitted via alternating current, the reactive power generated by the cable capacitance may cause an excessive over voltage in the middle of the transmission distance which requires unnecessary oversized cable voltage breakdown capability. The use of HVDC is usually required for transmission distance longer than 50 kilometers of submarine cables to be economical. The use of HVDC brings another advantage; it is capable of operating at variable frequency. The inland substation will be operated to 60 Hz synched with the grid, the offshore substation can be operated at variable frequency, thus allowing the wind power plant to be operated at constant Volt/Hz. In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated.

  7. A High Frequency Isolated Current-fed Bidirectional DC/AC Converter For Grid-Tied Energy Storage System

    E-Print Network [OSTI]

    King Jet, TSENG

    2013-01-01

    AC Converter for Grid-tied Energy Storage System XhaFreh qu,low energy resources, grid-tied energy storage systems (ESS)I. INTRODUCTION Grid-tied energy storage system (ESS) is

  8. A High Frequency Isolated Current-fed Bidirectional DC/AC Converter For Grid-Tied Energy Storage System

    E-Print Network [OSTI]

    King Jet, TSENG

    2013-01-01

    AC Converter for Grid-tied Energy Storage System XhaFreh qu,resources, grid-tied energy storage systems (ESS) will beincreasingly incorporated. Energy storage devices (ESD) such

  9. Comparing Two Types of Magnetically- Coupled Adjustable Speed Drives with Variable Frequency Drives in Pump and Fan Applications 

    E-Print Network [OSTI]

    Anderson, K. J.; Chvala, W. D.

    2003-01-01

    This paper presents the results from laboratory tests on MagnaDrive Corporations fixed-magnet magnetically-coupled adjustable speed drive (MC-ASD) and Coyote Electronics electromagnetic MC-ASD as compared to a typical variable frequency drive (VFD...

  10. Abstract--Time-frequency analysis of heart rate variability (HRV) makes it easier to evaluate how the balance

    E-Print Network [OSTI]

    Carvalho, João Luiz

    Abstract--Time-frequency analysis of heart rate variability (HRV) makes it easier to evaluate how-regressive model can be used to calculate the Power Spectrum Density of HRV and to create an auto of optimal orders for different interpolation rates of the HRV signal are presented. Keywords--AR model order

  11. Field Verification of Energy and Demand Savings of Two Injection Molding Machines Retrofitted with Variable Frequency Drives 

    E-Print Network [OSTI]

    Liou, S. P.; Aguiar, D.

    1999-01-01

    Detailed field measurements of energy consumption (kWh) and demand (kW) are conducted on two injection molding machines (IMMs) used in a typical plastic manufacturing facility in the San Francisco Bay Area, with/without Variable Frequency Drives...

  12. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    SciTech Connect (OSTI)

    Eto, Joseph H.; Undrill, John; Mackin, Peter; Daschmans, Ron; Williams, Ben; Haney, Brian; Hunt, Randall; Ellis, Jeff; Illian, Howard; Martinez, Carlos; O'Malley, Mark; Coughlin, Katie; LaCommare, Kristina Hamachi

    2010-12-20

    An interconnected electric power system is a complex system that must be operated within a safe frequency range in order to reliably maintain the instantaneous balance between generation and load. This is accomplished by ensuring that adequate resources are available to respond to expected and unexpected imbalances and restoring frequency to its scheduled value in order to ensure uninterrupted electric service to customers. Electrical systems must be flexible enough to reliably operate under a variety of"change" scenarios. System planners and operators must understand how other parts of the system change in response to the initial change, and need tools to manage such changes to ensure reliable operation within the scheduled frequency range. This report presents a systematic approach to identifying metrics that are useful for operating and planning a reliable system with increased amounts of variable renewable generation which builds on existing industry practices for frequency control after unexpected loss of a large amount of generation. The report introduces a set of metrics or tools for measuring the adequacy of frequency response within an interconnection. Based on the concept of the frequency nadir, these metrics take advantage of new information gathering and processing capabilities that system operators are developing for wide-area situational awareness. Primary frequency response is the leading metric that will be used by this report to assess the adequacy of primary frequency control reserves necessary to ensure reliable operation. It measures what is needed to arrest frequency decline (i.e., to establish frequency nadir) at a frequency higher than the highest set point for under-frequency load shedding within an interconnection. These metrics can be used to guide the reliable operation of an interconnection under changing circumstances.

  13. The bi-variate frequency distribution of two concurrent climatic variables: a study of temperature and dew point 

    E-Print Network [OSTI]

    Zeitler, Jon William

    1991-01-01

    Study of Temperature and Dew Point (December 1991). Jon William Zeitler, B. S. , iowa State University Chair of Advisory Comminee; Prof. John F. Griffiths The bi-variate normal distribution was fitted for the mid-season months of January, April, July... as to style and content by: Jo F. Griffnhs "' (Chair of Committee) Robert C. Runnels (Member) J. ' e (Mem r) Edward J. ser (Head of Department) December 1991 ABSTRACT The Bi-Variate Frequency Distribution of Two Concurrent Climatic Variables: A...

  14. GEOPHYSICAL RESEARCH LETTERS, VOL. 28, NO. 9, PAGES 1755-1758, MAY 1, 2001 Aliasing of high-frequency variability by altimetry

    E-Print Network [OSTI]

    Griesel, Alexa

    GEOPHYSICAL RESEARCH LETTERS, VOL. 28, NO. 9, PAGES 1755-1758, MAY 1, 2001 Aliasing of high-frequency at 10-day intervals are likely to alias substantial amounts of unresolved high-frequency vari- ability modeling studies have found sig- nificant high-frequency surface pressure variability, partic- ularly

  15. The New Active Output Filter for Variable Speed Constant Frequency Aerospace Applications 

    E-Print Network [OSTI]

    Alhuwaishel, Fahad

    2015-08-06

    capacitor filter. Moreover, the main square wave inverter has a capability to regulate the output voltage depending on the Load requirements providing a wide range of modulation index. The operation principle of the concept is demonstrated for Variable Speed...

  16. The millimetre variability of M81* -- Multi-epoch dual frequency mm-observations of the nucleus of M81

    E-Print Network [OSTI]

    R. Schoedel; M. Krips; S. Markoff; R. Neri; A. Eckart

    2006-11-28

    There are still many open questions as to the physical mechanisms at work in Low Luminosity AGN that accrete in the extreme sub-Eddington regime. Simultaneous multi-wavelength studies have been very successful in constraining the properties of SgrA*, the extremely sub-Eddington black hole at the centre of our Milky Way. M81*, the nucleus of the nearby spiral galaxy M81, is an ideal source to extend the insights obtained on SgrA* toward higher luminosity AGN. Here we present observations at 3 and 1 mm that were obtained within the framework of a coordinated,multi-wavelength campaign on M81*. The continuum emission from M81* was observed during three epochs with the IRAM Plateau de Bure Interferometer simultaneously at wavelengths of 3 and 1 mm. We present the first flux measurements of M81* at wavelengths around 1 mm. We find that M81* is a continuously variable source with the higher variability observed at the shorter wavelength. Also, the variability at 3 and 1 mm appears to be correlated. Like SgrA*, M81* appears to display the strongest flux density and variability in the mm-to-submm regime. There remains still some ambiguity concerning the exact location of the turnover frequency from optically thick to optically thin emission. The observed variability time scales point to an upper size limit of the emitting region of the order 25 Schwarzschild radii. The data show that M81* is indeed a system with very similar physical properties to SgrA* and an ideal bridge toward high luminosity AGN. The data obtained clearly demonstrate the usefulness and, above all, the necessity of simultaneous multi-wavelength observations of LLAGN.

  17. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    plants to frequency response during disturbances. Use ofkey event during a disturbance when the frequency stabilizesrestore frequency to normal following a disturbance and is

  18. Temporal Variability of Waves at the Proton Cyclotron Frequency Upstream from Mars: Implications for Mars Distant Hydrogen Exosphere

    E-Print Network [OSTI]

    Bertucci, Cesar; Chaufray, Jean-Yves; Gomez, Daniel; Mazelle, Christian; Delva, Magda; Modolo, Ronan; Gonzalez-Galindo, Francisco; Brain, David Andrew

    2013-01-01

    We report on the temporal variability of the occurrence of waves at the local proton cyclotron frequency upstream from the Martian bow shock from Mars Global Surveyor observations during the first aerobraking and science phasing orbit periods. Observations at high southern latitudes during minimum-to-mean solar activity show that the wave occurrence rate is significantly higher around perihelion southern summer solstice and lower around the same hemisphere's spring and autumn equinoxes. A similar trend is observed in the hydrogen (H) exospheric density profiles over the Martian South Pole obtained from a model including UV thermospheric heating effects. In spite of the complexity in the ion pick-up and plasma wave generation and evolution processes, these results support the idea that variations in the occurrence of waves could be used to study the temporal evolution of the distant Martian H corona and its coupling with the thermosphere at altitudes currently inaccessible to direct measurements.

  19. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    and energy storage. Use of Frequency Response Metrics toand energy storage. xxix Use of Frequency Response Metricsfrequency control such as demand response and energy storage.

  20. Variable Frequency Drives

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentric viewingValidatingRoadmapVannevar Bush andCSV

  1. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    wind Time (Seconds) Figure 5-3. The Power Delivered by Primary Frequency Control Actions via Generator

  2. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    load shedding is greater than the amount of generation that was lost, frequency will quickly rise and exceed the scheduled value.

  3. Use of Frequency Response Metrics to Assess the Planning and Operating Requirements for Reliable Integration of Variable Renewable Generation

    E-Print Network [OSTI]

    Eto, Joseph H.

    2011-01-01

    Integration of Variable Renewable Generation The report isISO (CAISO). 2007. Integration of Renewable Resources.recommendations for integrating renewable resources on the

  4. english 31AC african-amercan studies 17AC history 7B public health 130AC sociology 3AC education 30AC ethnic studies 135AC geography 150AC history 127AC information 142AC psychology 125AC anthropology 2AC american

    E-Print Network [OSTI]

    Alvarez-Cohen, Lisa

    · anthropology 2AC · american studies 10AC · gender and womens studies 50AC · music 26AC · spanish 135AC 50AC · music 26AC · spanish 135AC · sociology 190AC · public policy 117AC · peace and conflict studies 10AC · gender and womens studies 50AC · music 26AC · spanish 135AC · sociology 190AC · public

  5. Abstract--A high frequency AC current-sourcing driver that can feed electrical loads with a constant current that is

    E-Print Network [OSTI]

    maintaining high efficiency and low output crest factor. The CCTC is realized, in present work, by a multi's efficiency [1] ­ [3]. For example, fluorescent lamps need to be driven by a source that features high output approach would be to generate high frequency signal by a switch mode resonant inverter (Fig. 1) since

  6. Collaborative Research: Process-Resolving Decomposition of the Global Temperature Response to Modes of Low Frequency Variability in a Changing Climate

    SciTech Connect (OSTI)

    Deng, Yi

    2014-11-24

    DOE-GTRC-05596 11/24/2104 Collaborative Research: Process-Resolving Decomposition of the Global Temperature Response to Modes of Low Frequency Variability in a Changing Climate PI: Dr. Yi Deng (PI) School of Earth and Atmospheric Sciences Georgia Institute of Technology 404-385-1821, yi.deng@eas.gatech.edu El Niño-Southern Oscillation (ENSO) and Annular Modes (AMs) represent respectively the most important modes of low frequency variability in the tropical and extratropical circulations. The projection of future changes in the ENSO and AM variability, however, remains highly uncertain with the state-of-the-science climate models. This project conducted a process-resolving, quantitative evaluations of the ENSO and AM variability in the modern reanalysis observations and in climate model simulations. The goal is to identify and understand the sources of uncertainty and biases in models’ representation of ENSO and AM variability. Using a feedback analysis method originally formulated by one of the collaborative PIs, we partitioned the 3D atmospheric temperature anomalies and surface temperature anomalies associated with ENSO and AM variability into components linked to 1) radiation-related thermodynamic processes such as cloud and water vapor feedbacks, 2) local dynamical processes including convection and turbulent/diffusive energy transfer and 3) non-local dynamical processes such as the horizontal energy transport in the oceans and atmosphere. In the past 4 years, the research conducted at Georgia Tech under the support of this project has led to 15 peer-reviewed publications and 9 conference/workshop presentations. Two graduate students and one postdoctoral fellow also received research training through participating the project activities. This final technical report summarizes key scientific discoveries we made and provides also a list of all publications and conference presentations resulted from research activities at Georgia Tech. The main findings include: 1) the distinctly different roles played by atmospheric dynamical processes in establishing surface temperature response to ENSO at tropics and extratropics (i.e., atmospheric dynamics disperses energy out of tropics during ENSO warm events and modulate surface temperature at mid-, high-latitudes through controlling downward longwave radiation); 2) the representations of ENSO-related temperature response in climate models fail to converge at the process-level particularly over extratropics (i.e., models produce the right temperature responses to ENSO but with wrong reasons); 3) water vapor feedback contributes substantially to the temperature anomalies found over U.S. during different phases of the Northern Annular Mode (NAM), which adds new insight to the traditional picture that cold/warm advective processes are the main drivers of local temperature responses to the NAM; 4) the overall land surface temperature biases in the latest NCAR model (CESM1) are caused by biases in surface albedo while the surface temperature biases over ocean are related to multiple factors including biases in model albedo, cloud and oceanic dynamics, and the temperature biases over different ocean basins are also induced by different process biases. These results provide a detailed guidance for process-level model turning and improvement, and thus contribute directly to the overall goal of reducing model uncertainty in projecting future changes in the Earth’s climate system, especially in the ENSO and AM variability.

  7. Frequency modulation drive for a piezoelectric motor

    DOE Patents [OSTI]

    Mittas, Anthony (Albuquerque, NM)

    2001-01-01

    A piezoelectric motor has peak performance at a specific frequency f.sub.1 that may vary over a range of frequencies. A drive system is disclosed for operating such a motor at peak performance without feedback. The drive system consists of the motor and an ac source connected to power the motor, the ac source repeatedly generating a frequency over a range from f.sub.1 -.DELTA.x to f.sub.1 +.DELTA.y.

  8. Digital ac monitor

    DOE Patents [OSTI]

    Hart, George W. (Natick, MA); Kern, Jr., Edward C. (Lincoln, MA)

    1987-06-09

    An apparatus and method is provided for monitoring a plurality of analog ac circuits by sampling the voltage and current waveform in each circuit at predetermined intervals, converting the analog current and voltage samples to digital format, storing the digitized current and voltage samples and using the stored digitized current and voltage samples to calculate a variety of electrical parameters; some of which are derived from the stored samples. The non-derived quantities are repeatedly calculated and stored over many separate cycles then averaged. The derived quantities are then calculated at the end of an averaging period. This produces a more accurate reading, especially when averaging over a period in which the power varies over a wide dynamic range. Frequency is measured by timing three cycles of the voltage waveform using the upward zero crossover point as a starting point for a digital timer.

  9. Digital ac monitor

    DOE Patents [OSTI]

    Hart, G.W.; Kern, E.C. Jr.

    1987-06-09

    An apparatus and method is provided for monitoring a plurality of analog ac circuits by sampling the voltage and current waveform in each circuit at predetermined intervals, converting the analog current and voltage samples to digital format, storing the digitized current and voltage samples and using the stored digitized current and voltage samples to calculate a variety of electrical parameters; some of which are derived from the stored samples. The non-derived quantities are repeatedly calculated and stored over many separate cycles then averaged. The derived quantities are then calculated at the end of an averaging period. This produces a more accurate reading, especially when averaging over a period in which the power varies over a wide dynamic range. Frequency is measured by timing three cycles of the voltage waveform using the upward zero crossover point as a starting point for a digital timer. 24 figs.

  10. Hybrid immersed interface-immersed boundary methods for AC dielectrophoresis

    SciTech Connect (OSTI)

    Hossan, Mohammad Robiul [School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 (United States); Department of Engineering and Physics, University of Central Oklahoma, Edmond, OK 73034-5209 (United States); Dillon, Robert [Department of Mathematics, Washington State University, Pullman, WA 99164-3113 (United States); Dutta, Prashanta, E-mail: dutta@mail.wsu.edu [School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 (United States)

    2014-08-01

    Dielectrophoresis, a nonlinear electrokinetic transport mechanism, has become popular in many engineering applications including manipulation, characterization and actuation of biomaterials, particles and biological cells. In this paper, we present a hybrid immersed interface–immersed boundary method to study AC dielectrophoresis where an algorithm is developed to solve the complex Poisson equation using a real variable formulation. An immersed interface method is employed to obtain the AC electric field in a fluid media with suspended particles and an immersed boundary method is used for the fluid equations and particle transport. The convergence of the proposed algorithm as well as validation of the hybrid scheme with experimental results is presented. In this paper, the Maxwell stress tensor is used to calculate the dielectrophoretic force acting on particles by considering the physical effect of particles in the computational domain. Thus, this study eliminates the approximations used in point dipole methods for calculating dielectrophoretic force. A comparative study between Maxwell stress tensor and point dipole methods for computing dielectrophoretic forces are presented. The hybrid method is used to investigate the physics of dielectrophoresis in microfluidic devices using an AC electric field. The numerical results show that with proper design and appropriate selection of applied potential and frequency, global electric field minima can be obtained to facilitate multiple particle trapping by exploiting the mechanism of negative dielectrophoresis. Our numerical results also show that electrically neutral particles form a chain parallel to the applied electric field irrespective of their initial orientation when an AC electric field is applied. This proposed hybrid numerical scheme will help to better understand dielectrophoresis and to design and optimize microfluidic devices.

  11. Effective switching frequency multiplier inverter

    DOE Patents [OSTI]

    Su, Gui-Jia (Oak Ridge, TN); Peng, Fang Z. (Okemos, MI)

    2007-08-07

    A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

  12. Exploiting Passive Dynamics with Variable Stiffness Actuation in Robot Brachiation

    E-Print Network [OSTI]

    Vijayakumar, Sethu

    Exploiting Passive Dynamics with Variable Stiffness Actuation in Robot Brachiation Jun Nakanishi.nakanishi@ed.ac.uk, sethu.vijayakumar@ed.ac.uk Abstract--This paper explores a passive control strategy with variable present our passive control strategy considering a pendulum with variable stiffness actuation. Then, we

  13. 3.3.3AC Sweep AC . AC

    E-Print Network [OSTI]

    ­. DC ­ AC ­) .( . ­ ,, '­Spice .Spice . : 0 0 E1 PWR(V(%IN+, %IN . )2.3( Etable " . . : 00 V1 0Vdc E2 Pwr(V(%IN+, %IN-),2) ETABLE TABLE = (5

  14. Radio-Frequency Beam Conditioner for Fast-Wave Free-Electron Generators of Coherent Radiation

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01

    to Physical Review Letters Radio-Frequency Beam ConditionerDE-AC03-76SF00098 LBL-31006 RADIO-FREQUENCY BEAM CONDITIONERIbaraki, 305, Japan. RADIO-FREQUENCY BEAM CONDITIONER FOR

  15. Compressional wave character in gassy, near-surface sediments in southern Louisiana determined from variable frequency cross-well, borehole logging, and surface seismic measurements

    SciTech Connect (OSTI)

    Thompson, M.D.; McGinnis, L.D.; Wilkey, P.L. [Argonne National Lab., IL (United States); Fasnacht, T. [Gas Research Inst., Chicago, IL (United States)

    1995-06-01

    Velocity and attenuation data were used to test theoretical equations describing the frequency dependence of compressional wave velocity and attenuation through gas-rich sediments in coastal Louisiana. The cross-well data were augmented with velocities derived from a nearby seismic refraction station using a low-frequency source. Energy at 1 and 3 kHz was successfully transmitted over distances from 3.69 to 30 m; the 5 and 7-kHz data were obtained only at distances up to 20 m. Velocity tomograms were constructed for one borehole pair and covered a depth interval of 10--50 m. Results from the tomographic modeling indicate that gas-induced low velocities are present to depths of greater than 40 m. Analysis of the velocity dispersion suggests that gas-bubble resonance must be greater than 7 kHz, which is above the range of frequencies used in the experiment. Washout of the boreholes at depths above 15 m resulted in a degassed zone containing velocities higher than those indicated in both nearby refraction and reflection surveys. Velocity and attenuation information were obtained for a low-velocity zone centered at a depth of approximately 18 m. Measured attenuations of 1.57, 2.95, and 3.24 dB/m for the 3-, 5-, and 7-kHz signals, respectively, were modeled along with the velocity data using a silt-clay sediment type. Density and porosity data for the model were obtained from the geophysical logs; the bulk and shear moduli were estimated from published relationships. Modeling results indicate that gas bubbles measuring 1 mm in diameter occupy at least 25% to 35% of the pore space.

  16. Tensor products of AC charges and AC Radon measures are not always AC charges

    E-Print Network [OSTI]

    Buczolich, Zoltán

    Tensor products of AC #3; charges and AC Radon measures are not always AC #3; charges Zolt#19;an and an absolutely continuous Radon measure #22; on R such that F #22; is not an AC#3; charge on R 2 . 1 Introduction In [1] the tensor problem was stated for the tensor product of AC #3; charges and the Lebesgue

  17. Optimization of spin-torque switching using AC and DC pulses

    SciTech Connect (OSTI)

    Dunn, Tom [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Kamenev, Alex [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-06-21

    We explore spin-torque induced magnetic reversal in magnetic tunnel junctions using combined AC and DC spin-current pulses. We calculate the optimal pulse times and current strengths for both AC and DC pulses as well as the optimal AC signal frequency, needed to minimize the Joule heat lost during the switching process. The results of this optimization are compared against numeric simulations. Finally, we show how this optimization leads to different dynamic regimes, where switching is optimized by either a purely AC or DC spin-current, or a combination AC/DC spin-current, depending on the anisotropy energies and the spin-current polarization.

  18. Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine

    E-Print Network [OSTI]

    Silva, Filipe Faria Da

    Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine-Frequency Control (LFC) is gradually shifted to Variable Speed Wind Turbines (VSWTs). In order to equip VSWT

  19. AC susceptibility studies of high-[Tc] superconductors

    SciTech Connect (OSTI)

    Lee, Chang-Young.

    1993-01-01

    In this thesis, the authors studied physical properties of various high-T[sub c] superconductors by means of the ac susceptibility technique. They present the physics of ac susceptibility from first principles without relying on any specific models. From this, they can explain some fundamental but interesting features of experimental results such as symmetry properties of the ac susceptibility and its harmonics with respect to dc magnetic field. By measuring ac hysteresis they were able to obtain lower critical fields which were compared with some theoretical predictions. They found that the results were consistent with the BCS theory with modified gap parameter. By measuring ac hysteresis of granular samples at ultra low magnetic fields, they revealed the Meissner state and obtained Josephson lower critical fields, which was also found to be in consistence with the BCS theory. They studied the critical state models in detail and obtained some useful equations which were used in analyzing magnetic field dependence of ac susceptibility. By comparing the equations with experimental results, they were able to perform quantitative analysis of some important physical parameters such as critical current density. From numerical calculations of ac susceptibility with the parameter values obtained by this procedure, they confirmed good agreement of theory with experimental data. They incorporated the theory of flux creep into the equation governing the steady state flux motion, from which they were able to explain the shift of ac susceptibility with operating frequency toward high temperatures. Through this study, quantitative results on the activation energy were obtained.

  20. Tensor products of AC* charges and AC Radon measures are not always AC* charges

    E-Print Network [OSTI]

    Buczolich, Zoltán

    Tensor products of AC* charges and AC Radon measures are not always AC* charges] the tensor problem was stated for the tensor product of AC* charges and the Lebesgue measure. Later W: non-absolute integrals, variational measure, tensor product. 1

  1. Fluctuation of an ion beam extracted from an AC filament driven Bernas-type ion source

    SciTech Connect (OSTI)

    Miyamoto, N. Okajima, Y.; Wada, M.

    2014-02-15

    Argon ion beam fluctuation from an AC filament driven Bernas-type ion source is observed. The ion beam was measured by an 8 measurement elements beam profile monitor. The amplitude of the beam current fluctuation stayed in the same level from 100 Hz to 1 kHz of the filament heating frequency. The beam current fluctuation frequency measured by the beam profile monitor was equal to the frequency of the AC filament operation. The fluctuation amplitudes of the beam current by AC operation were less than 7% and were in the same level of the DC operation.

  2. Signal quality of the LHC AC dipoles and its impact on beam dynamics

    SciTech Connect (OSTI)

    Miyamoto, R.; Cattin, M.; Serrano, J.; Tomas, R.

    2010-05-23

    The adiabaticity of the AC dipole might be compromised by noise or unwanted frequency components in its signal. An effort has been put to characterize and optimize the signal quality of the LHC AC dipoles. The measured signal is used in realistic simulations in order to evaluate its impact on beam dynamics and to ultimately establish safe margins for the operation of the LHC AC dipoles.

  3. Power conversion architecture for grid interface at high switching frequency

    E-Print Network [OSTI]

    Lim, Seungbum

    This paper presents a new power conversion architecture for single-phase grid interface. The proposed architecture is suitable for realizing miniaturized ac-dc converters operating at high frequencies (HF, above 3 MHz) and ...

  4. Monitoring method and apparatus using high-frequency carrier

    DOE Patents [OSTI]

    Haynes, Howard D. (Knoxville, TN)

    1996-01-01

    A method and apparatus for monitoring an electrical-motor-driven device by injecting a high frequency carrier signal onto the power line current. The method is accomplished by injecting a high frequency carrier signal onto an AC power line current. The AC power line current supplies the electrical-motor-driven device with electrical energy. As a result, electrical and mechanical characteristics of the electrical-motor-driven device modulate the high frequency carrier signal and the AC power line current. The high frequency carrier signal is then monitored, conditioned and demodulated. Finally, the modulated high frequency carrier signal is analyzed to ascertain the operating condition of the electrical-motor-driven device.

  5. Monitoring method and apparatus using high-frequency carrier

    DOE Patents [OSTI]

    Haynes, H.D.

    1996-04-30

    A method and apparatus for monitoring an electrical-motor-driven device by injecting a high frequency carrier signal onto the power line current. The method is accomplished by injecting a high frequency carrier signal onto an AC power line current. The AC power line current supplies the electrical-motor-driven device with electrical energy. As a result, electrical and mechanical characteristics of the electrical-motor-driven device modulate the high frequency carrier signal and the AC power line current. The high frequency carrier signal is then monitored, conditioned and demodulated. Finally, the modulated high frequency carrier signal is analyzed to ascertain the operating condition of the electrical-motor-driven device. 6 figs.

  6. Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

    DOE Patents [OSTI]

    Pitel, I.J.

    1987-02-03

    The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage. 19 figs.

  7. Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

    DOE Patents [OSTI]

    Pitel, Ira J. (Whippany, NJ)

    1987-02-03

    The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage.

  8. ACS Web Editions/ACS Legacy Archives Multiple Site/Consortium Sales Agreement Page 1 of 2

    E-Print Network [OSTI]

    Kisiel, Zbigniew

    ACS Web Editions/ACS Legacy Archives Multiple Site/Consortium Sales Agreement Page 1 of 2 I. Czasopisma ACS Web Edition 1. Accounts of Chemical Research 2. ACS Applied Materials & Interfaces 3. ACS Letters http://pubs.acs.org/journal/jpclcd #12;ACS Web Editions/ACS Legacy Archives Multiple Site

  9. Digital slip frequency generator and method for determining the desired slip frequency

    DOE Patents [OSTI]

    Klein, Frederick F. (Monroeville, PA)

    1989-01-01

    The output frequency of an electric power generator is kept constant with variable rotor speed by automatic adjustment of the excitation slip frequency. The invention features a digital slip frequency generator which provides sine and cosine waveforms from a look-up table, which are combined with real and reactive power output of the power generator.

  10. Low and high frequency approximations to eigenvibrations in a string with double

    E-Print Network [OSTI]

    Scheichl, Robert

    Low and high frequency approximations to eigenvibrations in a string with double contrasts Natalia://www.bath.ac.uk/math-sci/BICS #12;Low and high frequency approximations to eigenvibrations of string with double contrasts Natalia as the order of stiffness inhomogeneity, with heavier part being softer. The limit problem for high frequency

  11. Bulk Power System Dynamics and Control VIII, August 1-6, 2010, Buzios, Rio de Janeiro, Brazil Impact of Delays on a Consensus-based Primary Frequency Control Scheme

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    with the power system's ability to return to its nominal frequency after a severe disturbance resulting Impact of Delays on a Consensus-based Primary Frequency Control Scheme for AC Systems Connected This paper addresses the problem of sharing primary frequency control reserves among non- synchronous AC

  12. High-frequency irradiance fluctuations and geographic smoothing

    E-Print Network [OSTI]

    Lave, Matthew; Kleissl, Jan; Arias-Castro, Ery

    2012-01-01

    of the variability of irradiance and PV power time series1997. Study of areal solar irradiance for analyzing areally-High-frequency irradiance fluctuations and geographic

  13. Controller for controlling operation of at least one electrical load operating on an AC supply, and a method thereof

    DOE Patents [OSTI]

    Cantin, Luc (Baie Comeau, CA); Deschenes, Mario (Baie Comeau, CA); D'Amours, Mario (Sept Iles, CA)

    1995-08-15

    A controller is provided for controlling operation of at least one electrical load operating on an AC supply having a typical frequency, the AC supply being provided via power transformers by an electrical power distribution grid. The controller is associated with the load and comprises an input interface for coupling the controller to the grid, a frequency detector for detecting the frequency of the AC supply and producing a signal indicative of the frequency, memory modules for storing preprogrammed commands, a frequency monitor for reading the signal indicative of the frequency and producing frequency data derived thereof, a selector for selecting at least one of the preprogrammed commands with respect to the frequency data, a control unit for producing at least one command signal representative of the selected preprogrammed commands, and an output interface including a device responsive to the command signal for controlling the load. Therefore, the load can be controlled by means of the controller depending on the frequency of the AC supply.

  14. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, C.M.

    1998-12-15

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine is described. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod. 8 figs.

  15. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, Carsten M. (Dadeville, AL)

    1998-01-01

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod.

  16. Memory Power Management via Dynamic Voltage/Frequency Scaling

    E-Print Network [OSTI]

    Mutlu, Onur

    *Dual 4-core Intel Xeon®, 48GB DDR3 (12 DIMMs), SPEC CPU2006, all cores active. Measured AC power, analytically modeled memory power. #12;Existing Solution: Memory Sleep States? n Most memory energy for SPEC CPU2006 #12;Memory Power can be Scaled Down n DDR can operate at multiple frequencies à

  17. Power Conversion Architecture for Grid Interface at High Switching Frequency

    E-Print Network [OSTI]

    Perreault, Dave

    voltage from the voltage of energy buffer capacitor. The boost converter is often selected for PFC circuit output powers). Instead of a boost converter, one alternative for the PFC circuit is a buck converter is suitable for realizing miniaturized ac-dc converters operating at high frequencies (HF, above 3 MHz

  18. Multivariate High-Frequency-Based Volatility (HEAVY) Models Diaa Noureldin

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    Multivariate High-Frequency-Based Volatility (HEAVY) Models Diaa Noureldin Department of Economics.sheppard@economics.ox.ac.uk February 18, 2011 Abstract This paper introduces a new class of multivariate volatility models multivariate GARCH models. We also discuss their covariance targeting speci...cation and provide closed

  19. Nuclear structure of Ac-231

    E-Print Network [OSTI]

    R. Boutami; M. J. G. Borge; H. Mach; W. Kurcewicz; L. M. Fraile; K. Gulda; A. J. Aas; L. M. García-Raffi; G. Løvhøiden; T. Martínez; B. Rubio; J. L. Taín; O. Tengblad

    2008-08-06

    The low-energy structure of 231Ac has been investigated by means of gamma ray spectroscopy following the beta-decay of 231Ra. Multipolarities of 28 transitions have been established by measuring conversion electrons with a mini-orange electron spectrometer. The decay scheme of 231Ra --> 231Ac has been constructed for the first time. The Advanced Time Delayed beta-gamma-gamma(t) method has been used to measure the half-lives of five levels. The moderately fast B(E1) transition rates derived suggest that the octupole effects, albeit weak, are still present in this exotic nucleus.

  20. Variable Speed Pumping for Level Control 

    E-Print Network [OSTI]

    Vasel, M.

    1982-01-01

    analysis, and a brief discussion of variable frequency drive design considerations. Energy savings figures are based upon actual electricity costs at the plant involved. Process duty cycle and energy requirement levels were verified by a wattmeter...

  1. Strongly nonlinear dynamics of electrolytes in large ac voltages Laurits Hjgaard Olesen,1,2

    E-Print Network [OSTI]

    the results have been developed for over a century 1 . Current applications include energy storage; published 2 July 2010 We study the response of a model microelectrochemical cell to a large ac voltage of frequency comparable to the inverse cell relaxation time. To bring out the basic physics, we consider

  2. AA Architecture Building AC Athletics

    E-Print Network [OSTI]

    Kranakis, Evangelos

    $ AA Architecture Building AC Athletics AH Alumni Hall AP Azrieli Pavilion AT Azrieli Theatre CB Canal Building CC Colonel By Child Care Centre CO Residence Commons (Fenn Lounge) DH Dundas House DT Dunton Tower Interaction Building HP Herzberg Laboratories IH Ice House LA Loeb Building LE Leeds House LH Lanark House LS

  3. Cataclysmic Variables

    E-Print Network [OSTI]

    Robert Connon Smith

    2007-01-23

    Cataclysmic variables are binary stars in which a relatively normal star is transferring mass to its compact companion. This interaction gives rise to a rich range of behaviour, of which the most noticeable are the outbursts that give the class its name. Novae belong to the class, as do the less well known dwarf novae and magnetic systems. Novae draw their energy from nuclear reactions, while dwarf novae rely on gravity to power their smaller eruptions. All the different classes of cataclysmic variable can be accommodated within a single framework and this article will describe the framework, review the properties of the main types of system and discuss models of the outbursts and of the long-term evolution.

  4. The true Cramer-Rao bound for carrier frequency estimation from a Nele Noels, Heidi Steendam and Marc Moeneclaey

    E-Print Network [OSTI]

    Noels, Nele

    Steendam and Marc Moeneclaey Telecommunications and Information Processing (TELIN) department, Ghent University, St-Pietersnieuwstraat 41, B-9000 Gent, Belgium {nnoels, Marc.Moeneclaey}@telin.rug.ac.be Tel synchronization; frequency estimation Corresponding author: Marc Moeneclaey Telecommunications and Information

  5. Simultaneous distribution of AC and DC power

    DOE Patents [OSTI]

    Polese, Luigi Gentile

    2015-09-15

    A system and method for the transport and distribution of both AC (alternating current) power and DC (direct current) power over wiring infrastructure normally used for distributing AC power only, for example, residential and/or commercial buildings' electrical wires is disclosed and taught. The system and method permits the combining of AC and DC power sources and the simultaneous distribution of the resulting power over the same wiring. At the utilization site a complementary device permits the separation of the DC power from the AC power and their reconstruction, for use in conventional AC-only and DC-only devices.

  6. AC electrokinetic manipulation of selenium nanoparticles for potential nanosensor applications

    SciTech Connect (OSTI)

    Mahmoodi, Seyed Reza; Bayati, Marzieh; Hosseinirad, Somayeh; Foroumadi, Alireza; Gilani, Kambiz; Rezayat, Seyed Mahdi

    2013-03-15

    Highlights: ? Se nanoparticles were synthesized using a reverse-microemulsion process. ? AC osmotic fluid flow repulses the particles from electrode edges. ? Dielectrophoretic force attracts the particles to electrode edges. ? Dielectrophoresis electrode showed non-ohmic behavior. ? The device can potentially be used as a nanosensor. - Abstract: We report the AC electrokinetic behavior of selenium (Se) nanoparticles for electrical characterization and possible application as micro/nano devices. selenium Se nanoparticles were successfully synthesized using a reverse-microemulsion process and investigated structurally using X-ray diffraction and transmission electron microscope. Interdigitated castellated ITO and non-castellated platinum electrodes were employed for manipulation of suspended materials in the fluid. Using ITO electrodes at low frequency limits resulted in deposition of Se particles on electrode surface. When Se particles exposed to platinum electrodes in the 10 Hz–1 kHz range and V {sub p?p}> 8, AC osmotic fluid flow repulses the particles from electrode edges. However, in 10 kHz–10 MHz range and V {sub p?p}> 5, dielectrophoretic force attracts the particles to electrode edges. As the Se particle concentration increased, the trapped Se particles were aligned along the electric field line and bridged the electrode gap. The device was characterized and can potentially be useful in making micro/nano electronic devices.

  7. RESEARCH ARTICLE Empirical assessment of short-term variability from

    E-Print Network [OSTI]

    with a total installed capacity of 195MW (AC); it is based on minute-averaged data from each plantRESEARCH ARTICLE Empirical assessment of short-term variability from utility-scale solar PV plants 10027, USA 2 First Solar, Inc., 350 West Washington Street, Suite 600, Tempe, AZ 85281, USA ABSTRACT

  8. Sparse Bayesian Variable Selection for the Identification of Antigenic Variability in the Foot-and-Mouth Disease Virus

    E-Print Network [OSTI]

    Kaski, Samuel

    of Glasgow, UK v.davies.1@research.gla.ac.uk Boyd Orr Centre for Population and Ecosystem Health model using spike and slab priors which is able to predict antigenic variability and identify sites of new virus strains, the need to produce effective vaccines has become ever more vital. Predicting where

  9. Low-frequency interaction between horizontal and overturning gyres in the ocean

    E-Print Network [OSTI]

    Low-frequency interaction between horizontal and overturning gyres in the ocean M. A. Spall1] Low-frequency variability of the horizontal circulation in an idealized, eddy-permitting, numerical model drives the dominant mode of low-frequency variability in the meridional overturning circulation

  10. AC Transit | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Financing ToolInternationalReportOffice | DepartmentVery1, in:QuarterlyA SolarAADensifiedAC

  11. Bayesian latent variable modelling in studies of air pollution and health

    E-Print Network [OSTI]

    Scheichl, Robert

    Bayesian latent variable modelling in studies of air pollution and health Duncan Lee, Gavin://www.bath.ac.uk/math-sci/BICS #12;Bayesian latent variable modelling in studies of air pollution and health. Duncan Lee (1), Gavin to air pollution on respiratory mortality in the elderly (aged 65 and above) in London, England, between

  12. www.accommodation.salford.ac.uk Accommodation

    E-Print Network [OSTI]

    Romano, Daniela

    sets out the main elements of good management practice. It covers health and safety, maintenancewww.accommodation.salford.ac.uk Accommodation Guide to University and University partner accommodation #12;32 www.accommodation.salford.ac.ukA guide to University and Partner accommodation Welcome

  13. Conservation Theory Process Control Using Variable Frequency Drives 

    E-Print Network [OSTI]

    Myers, N. S.

    1980-01-01

    stream_source_info ESL-IE-80-04-104.pdf.txt stream_content_type text/plain stream_size 12263 Content-Encoding ISO-8859-1 stream_name ESL-IE-80-04-104.pdf.txt Content-Type text/plain; charset=ISO-8859-1 CONSERVATION... staffs of most companies to evaluate the energy consumption and effi ciency of new and existing facilities. Some of the energy conserving equipment which seemed too costly or complex a few short years ago are now becoming the engineer's strongest...

  14. Variable Frequency Motor Drives: Harmonics, Power Factor, and Energy Efficiency 

    E-Print Network [OSTI]

    Massey, G. W.

    1997-01-01

    harmonics and power factor. NOTE: The views expressed in this paper do not necessarily represent the views of the United States of America, the U.S. Department of Justice, or the Federal Bureau of Prisons....

  15. Frequency comb swept lasers

    E-Print Network [OSTI]

    Tsai, Tsung-Han

    We demonstrate a frequency comb (FC) swept laser and a frequency comb Fourier domain mode locked (FC-FDML) laser for applications in optical coherence tomography (OCT). The fiber-based FC swept lasers operate at a sweep ...

  16. A Battery-less, Wireless Mote for Scavenging Wireless Power at UHF (470-570 MHz) Frequencies

    E-Print Network [OSTI]

    Tentzeris, Manos

    A Battery-less, Wireless Mote for Scavenging Wireless Power at UHF (470-570 MHz) Frequencies Rushi Vyas*, Vasileios Lakafosis, Dr. Manos Tentzeris School of Electrical and Computer Engineering, Georgia@akg.t.u-tokyo.ac.jp Abstract--In this paper, a novel power scavenging mote to harness wireless power in the UHF frequencies

  17. Eastern Frequency Response Study

    SciTech Connect (OSTI)

    Miller, N.W.; Shao, M.; Pajic, S.; D'Aquila, R.

    2013-05-01

    This study was specifically designed to investigate the frequency response of the Eastern Interconnection that results from large loss-of-generation events of the type targeted by the North American Electric Reliability Corp. Standard BAL-003 Frequency Response and Frequency Bias Setting (NERC 2012a), under possible future system conditions with high levels of wind generation.

  18. Nonparametric estimation of econometric models with categorical variables 

    E-Print Network [OSTI]

    Ouyang, Desheng

    2006-10-30

    shows that regression model with only discrete vari- ables differs significantly from the mixed discrete and continuous variables case. In the mixed variable case with at least one relevant continuous regressor, the irrele- vant variables can be smoothed... CV-based estimator has a high probability of smoothing out the irrele- vant variable, hence it leads to a more efficient (in finite samples) estimation result than the frequency estimator. It is interesting to observe that our nonparametric CV...

  19. Radio frequency detection assembly and method for detecting radio frequencies

    DOE Patents [OSTI]

    Cown, Steven H. (Rigby, ID); Derr, Kurt Warren (Idaho Falls, ID)

    2010-03-16

    A radio frequency detection assembly is described and which includes a radio frequency detector which detects a radio frequency emission produced by a radio frequency emitter from a given location which is remote relative to the radio frequency detector; a location assembly electrically coupled with the radio frequency detector and which is operable to estimate the location of the radio frequency emitter from the radio frequency emission which has been received; and a radio frequency transmitter electrically coupled with the radio frequency detector and the location assembly, and which transmits a radio frequency signal which reports the presence of the radio frequency emitter.

  20. EESA: 802.11ac MU-MIMO spatial stream

    E-Print Network [OSTI]

    Bahk, Saewoong

    @snu.ac.kr EESA: Energy efficient spatial stream allocation technique in 802.11ac network Heo Jeong Ryun, Bahk Sae (1), (2) (1) . . spatial stream . 1 3. EESA(Energy Efficient 2014 EESA: 802.11ac MU-MIMO spatial stream , * jrheo@netlab.snu.ac.kr, sbahk

  1. 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

  2. Undergraduate study 2016 www.nottingham.ac.uk/medicine

    E-Print Network [OSTI]

    Qu, Rong

    Medicine Undergraduate study 2016 www.nottingham.ac.uk/medicine For general undergraduate enquiries: www.nottingham.ac.uk/faqs #12;21 School of Medicine www.nottingham.ac.uk/medicine School of Medicine www.nottingham.ac.uk/medicine Welcome to the School of Medicine You are about to embark

  3. AC-magnetotransport of a 2DEG in the quantum Hall regime

    SciTech Connect (OSTI)

    Hernández, C.; Chaubet, C.

    2014-05-15

    In this paper we present an ac-magneto-transport study of a two-dimensional electron gas (2DEG) in the quantum Hall effect (QHE) regime, for frequencies in the range [100Hz, 1MHz]. We present a new approach to understand admittance measurements based in the Landauer-Buttiker formalism for QHE edge channels and taking into account the capacitance and the topology of the cables connected to the contacts used in the measurements. Our model predicts an universal behavior with the a-dimensional parameter RC? where R is the 2 wires resistance of the 2DEG, C the capacitance cables and the angular frequency, in agreement with experiments.

  4. Understanding Inertial and Frequency Response of Wind Power Plants: Preprint

    SciTech Connect (OSTI)

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

    2012-07-01

    The objective of this paper is to analyze and quantify the inertia and frequency responses of wind power plants with different wind turbine technologies (particularly those of fixed speed, variable slip with rotor-resistance controls, and variable speed with vector controls).

  5. Lorentz Dispersion Law from classical Hydrogen electron orbits in AC electric field via geometric algebra

    E-Print Network [OSTI]

    Perez, Uzziel; Sugon, Quirino M; McNamara, Daniel J; Yoshikawa, Akimasa

    2015-01-01

    We studied the orbit of an electron revolving around an infinitely massive nucleus of a large classical Hydrogen atom subject to an AC electric field oscillating perpendicular to the electron's circular orbit. Using perturbation theory in geometric algebra, we show that the equation of motion of the electron perpendicular to the unperturbed orbital plane satisfies a forced simple harmonic oscillator equation found in Lorentz dispersion law in Optics. We show that even though we did not introduce a damping term, the initial orbital position and velocity of the electron results to a solution whose absorbed energies are finite at the dominant resonant frequency $\\omega=\\omega_0$; the electron slowly increases its amplitude of oscillation until it becomes ionized. We computed the average power absorbed by the electron both at the perturbing frequency and at the electron's orbital frequency. We graphed the trace of the angular momentum vector at different frequencies. We showed that at different perturbing frequen...

  6. Beat Frequency Modulation of T Tauri Accretion Rates

    E-Print Network [OSTI]

    K. W. Smith; I. A. Bonnell; G. F. Lewis

    1995-04-10

    A general model of magnetically controlled accretion onto T Tauri stars is presented. In this model the magnetic field is oriented arbitrarily in relation to the star's rotation axis. The resultant interplay between the magnetic field and accretion disc causes a variable accretion rate. The dominant timescale of this variability is the beat frequency between the stellar rotation frequency and the orbital frequency at the magnetosphere boundary. This model is analogous to that developed to explain quasi-periodic oscillations in low-mass X-ray binaries.

  7. Frequency Response Analysis Tool

    SciTech Connect (OSTI)

    Etingov, Pavel V.; Kosterev, Dmitry; Dai, T.

    2014-12-31

    Frequency response has received a lot of attention in recent years at the national level, which culminated in the development and approval of North American Electricity Reliability Corporation (NERC) BAL-003-1 Frequency Response and Frequency Bias Setting Reliability Standard. This report is prepared to describe the details of the work conducted by Pacific Northwest National Laboratory (PNNL) in collaboration with the Bonneville Power Administration and Western Electricity Coordinating Council (WECC) Joint Synchronized Information Subcommittee (JSIS) to develop a frequency response analysis tool (FRAT). The document provides the details on the methodology and main features of the FRAT. The tool manages the database of under-frequency events and calculates the frequency response baseline. Frequency response calculations are consistent with frequency response measure (FRM) in NERC BAL-003-1 for an interconnection and balancing authority. The FRAT can use both phasor measurement unit (PMU) data, where available, and supervisory control and data acquisition (SCADA) data. The tool is also capable of automatically generating NERC Frequency Response Survey (FRS) forms required by BAL-003-1 Standard.

  8. http://www.ecc.u-tokyo.ac.jp/doc/announce/newuser.html http://utroam.nc.u-tokyo.ac.jp/ [

    E-Print Network [OSTI]

    Goda, Keisuke

    OPAC TREEMyOPAC MyOPAC ()10 2 ECCS ECCS http://www.ecc.u-tokyo.ac.jp/doc/announce/newuser.html LAN LANutroam utroamECCS http://utroam.nc.u-tokyo.ac.jp/ [] ECCS http://www.dl.itc.u-tokyo.ac.jp/gacos/faq/gakugai.html http://www.dl.itc.u-tokyo.ac.jp/gacos/ http://www.dl.itc.u-tokyo.ac.jp/gacos/training.html https

  9. Analyzing and simulating the variability of solar irradiance and solar PV powerplants

    E-Print Network [OSTI]

    Lave, Matthew S.

    2012-01-01

    Hemker, T. Hoff, Short-term irradiance variability: StationLorenzo, D. Alvira, E. Izco, From irradiance to output power46 High Frequency Irradiance Fluctuations and Geographic

  10. 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)

    1984-03-20

    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.

  11. Soft Magnetic Materials in High-Frequency, High-Power Conversion Applications

    E-Print Network [OSTI]

    McHenry, Michael E.

    and facilitate two-way power conversion.7 Flexible alternating current (AC) Transmission Systems (FACTS) and High Voltage DC (HVDC) technologies aim to improve the effi- ciency of power networks and benefit from highSoft Magnetic Materials in High-Frequency, High-Power Conversion Applications ALEX M. LEARY,1

  12. Analysis and design of high frequency link power conversion systems for fuel cell power conditioning 

    E-Print Network [OSTI]

    Song, Yu Jin

    2005-11-01

    simulations and experiments, and their trade-offs are described in detail using mathematical evaluation approach. The third study proposes a current-fed high frequency link direct dc-ac converter suitable for residential fuel cell power systems. The high...

  13. A NOVEL APPROACH TO PROFILE CLOUD MICROPHYSICS USING DUAL-FREQUENCY RADARS

    E-Print Network [OSTI]

    .S. Department of Energy Office of Science ABSTRACT Single-frequency radar measurements provide insufficient Contract No. DE-AC02- 98CH10886 with the U.S. Department of Energy. The publisher by accepting-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others

  14. Experimental observation of very low-frequency macroscopic modes in a dusty plasma

    E-Print Network [OSTI]

    Goree, John

    -frequency discharge, with a vertical dc electric field that suspended the particles in the sheath region immediately not explicitly ac- count for the strong coupling that was present in the experi- ment. A similar interpretation was made by Barkan et al.,13 who used a video camera to record planar wave fronts of a polydisperse kaolin

  15. Stabilized radio frequency quadrupole

    DOE Patents [OSTI]

    Lancaster, Henry D. (Orinda, CA); Fugitt, Jock A. (Berkeley, CA); Howard, Donald R. (Danville, CA)

    1984-01-01

    A long-vane stabilized radio frequency resonator for accelerating charged particles and including means defining a radio frequency resonator cavity, a plurality of long vanes mounted in the defining means for dividing the cavity into sections, and means interconnecting opposing ones of the plurality of vanes for stabilizing the resonator.

  16. Resonant frequency detection and adjustment method for a capacitive transducer with differential transformer bridge

    SciTech Connect (OSTI)

    Hu, M.; Bai, Y. Z., E-mail: abai@mail.hust.edu.cn; Zhou, Z. B., E-mail: zhouzb@mail.hust.edu.cn; Li, Z. X.; Luo, J. [MOE Key Laboratory of Fundamental Physical Quantities Measurement, School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)] [MOE Key Laboratory of Fundamental Physical Quantities Measurement, School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-05-15

    The capacitive transducer with differential transformer bridge is widely used in ultra-sensitive space accelerometers due to their simple structure and high resolution. In this paper, the front-end electronics of an inductive-capacitive resonant bridge transducer is analyzed. The analysis result shows that the performance of this transducer depends upon the case that the AC pumping frequency operates at the resonance point of the inductive-capacitive bridge. The effect of possible mismatch between the AC pumping frequency and the actual resonant frequency is discussed, and the theoretical analysis indicates that the output voltage noise of the front-end electronics will deteriorate by a factor of about 3 due to either a 5% variation of the AC pumping frequency or a 10% variation of the tuning capacitance. A pre-scanning method to determine the actual resonant frequency is proposed followed by the adjustment of the operating frequency or the change of the tuning capacitance in order to maintain expected high resolution level. An experiment to verify the mismatching effect and the adjustment method is provided.

  17. jhchang@nova.snu.ac.kr {btzhang,ytkim}@cse.snu.ac.kr Helmholtz machine

    E-Print Network [OSTI]

    jhchang@nova.snu.ac.kr {btzhang,ytkim}@cse.snu.ac.kr Helmholtz machine . Helmholtz machine , . Helmholtz machine . , . (information gain) , Naïve Bayes . 1. (text categorization) . , . k- , Naïve Bayes, , support vector machine, PCA . , . . , . MCMC (Markov Chain Monte Carlo), Variational inference . Helmholtz

  18. Zigbee psy@netlab.snu.ac.kr, sbahk@snu.ac.kr

    E-Print Network [OSTI]

    Bahk, Saewoong

    2012 Zigbee , psy@netlab.snu.ac.kr, sbahk@snu.ac.kr Inter-protocol communication for energy efficient white space sensing of Zigbee device Se-Yong Park, Saewoong Bahk INMC, School of EECS, Seoul National University Zigbee WLAN , WLAN beacon preamble PHY

  19. Microfabricated ion frequency standard

    DOE Patents [OSTI]

    Schwindt, Peter (Albuquerque, NM); Biedermann, Grant (Albuquerque, NM); Blain, Matthew G. (Albuquerque, NM); Stick, Daniel L. (Albuquerque, NM); Serkland, Darwin K. (Albuquerque, NM); Olsson, III, Roy H. (Albuquerque, NM)

    2010-12-28

    A microfabricated ion frequency standard (i.e. an ion clock) is disclosed with a permanently-sealed vacuum package containing a source of ytterbium (Yb) ions and an octupole ion trap. The source of Yb ions is a micro-hotplate which generates Yb atoms which are then ionized by a ultraviolet light-emitting diode or a field-emission electron source. The octupole ion trap, which confines the Yb ions, is formed from suspended electrodes on a number of stacked-up substrates. A microwave source excites a ground-state transition frequency of the Yb ions, with a frequency-doubled vertical-external-cavity laser (VECSEL) then exciting the Yb ions up to an excited state to produce fluorescent light which is used to tune the microwave source to the ground-state transition frequency, with the microwave source providing a precise frequency output for the ion clock.

  20. IEEE 802.11 PSM happy1024@cs.yonsei.ac.kr, kimthun@cs.yonsei.ac.kr, yang@cs.yonsei.ac.kr

    E-Print Network [OSTI]

    Yang, Sung-Bong

    2 P2P IEEE 802.11 PSM O, , happy1024@cs.yonsei.ac.kr, kimthun@cs.yonsei.ac.kr, yang@cs.yonsei.ac.kr An Effective Power Saving Mechanism for IEEE 802.11 PSM In Double-layered Mobile P2P Systems JuHee Lee, Taek IEEE 802.11 (PSM) . PSM Beacon Interval Sleep . , Sleep

  1. Graphene Frequency Multipliers

    E-Print Network [OSTI]

    Wang, Han

    In this letter, the ambipolar transport properties of graphene flakes have been used to fabricate full-wave signal rectifiers and frequency-doubling devices. By correctly biasing an ambipolar graphene field-effect transistor ...

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

    DOE Patents [OSTI]

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

    2001-08-14

    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.

  3. High-frequency internal waves on a sloping shelf James M. Pringle1

    E-Print Network [OSTI]

    Pringle, James "Jamie"

    1 High-frequency internal waves on a sloping shelf James M. Pringle1 and Kenneth H. Brink Woods field propagating across a shelf and hence control the high- frequency variability on the shelf. This analysis exam- ines the evolution of the high-frequency internal wave field on the shelf as it is modified

  4. PV output variability modeling using satellite imagery.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Ellis, Abraham; Reno, Matthew J.

    2010-11-01

    High frequency irradiance variability measured on the ground is caused by the formation, dissipation, and passage of clouds in the sky. If we can identify and associate different cloud types/patterns from satellite imagery, we may be able to predict irradiance variability in areas lacking sensors. With satellite imagery covering the entire U.S., this allows for more accurate integration planning and power flow modeling over wide areas. Satellite imagery from southern Nevada was analyzed at 15 minute intervals over a year. Methods for image stabilization, cloud detection, and textural classification of clouds were developed and tested. High Performance Computing parallel processing algorithms were also investigated and tested. Artificial Neural Networks using imagery as inputs were trained on ground-based measurements of irradiance to model the variability and were tested to show some promise as a means for predicting irradiance variability.

  5. High fidelity ac gate operations of the quantum dot hybrid qubit

    E-Print Network [OSTI]

    Clement H. Wong

    2015-10-20

    Semiconductor quantum dots in silicon are promising qubits because of long spin coherence times and their potential for scalability. However, such qubits with complete electrical control and fidelities above the threshold for quantum error correction have not yet been achieved. We show theoretically that the threshold fidelity can be achieved with ac gate operation of the quantum dot hybrid qubit. Formed by three electrons in a double dot, this qubit is electrically controlled, does not require magnetic fields, and runs at GHz gate speeds. We analyze the decoherence caused by 1/f charge noise in this qubit, find parameters that minimize the charge noise dependence in the qubit frequency, and determine the optimal working points for ac gate operations that drive the detuning and tunnel coupling.

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

    E-Print Network [OSTI]

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

    2015-01-01

    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...

  7. 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

  8. When tensor products of AC charges and Radon

    E-Print Network [OSTI]

    Buczolich, Zoltán

    When tensor products of AC #3; charges and Radon measures are AC #3; charges Zolt#19;an Buczolich and Radon measures. We show that if F is a charge in R m which is AC#3; in a locally BV set E and #22; is an absolutely continuous Radon measure on R n with locally bounded Radon-Nikodym derivative then the charge F

  9. Undergraduate study 2016 www.nottingham.ac.uk/geography

    E-Print Network [OSTI]

    Nottingham, University of

    Geography Undergraduate study 2016 www.nottingham.ac.uk/geography For general undergraduate-enquiries@nottingham.ac.uk w: www.nottingham.ac.uk/faqs #12;The School of Geography at The University of Nottingham. As a Nottingham geography graduate you will have outstanding career prospects based on your specialist knowledge

  10. 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

  11. Variability of Behaviour in Electricity Load Profile Clustering; Who Does Things at the

    E-Print Network [OSTI]

    Aickelin, Uwe

    Variability of Behaviour in Electricity Load Profile Clustering; Who Does Things at the Same Time://ima.ac.uk/dent 2 The James Hutton Institute, Aberdeen, UK Abstract. UK electricity market changes provide opportunities to alter households' electricity usage patterns for the benefit of the overall elec- tricity

  12. DRIZZLE VARIABILITY IN MARINE STRATOCUMULUS IN THE AZORES Edward Luke and Pavlos Kollias

    E-Print Network [OSTI]

    DRIZZLE VARIABILITY IN MARINE STRATOCUMULUS IN THE AZORES Edward Luke and Pavlos Kollias Submitted Sciences Division/Environmental Sciences Dept. Brookhaven National Laboratory U.S. Department of Energy of Energy under Contract No. DE-AC02-98CH10886 ABSTRACT The U.S. Department of Energy Atmospheric Radiation

  13. r XXXX American Chemical Society 1353 dx.doi.org/10.1021/jz200194e |J. Phys. Chem. Lett. 2011, 2, 13531358 pubs.acs.org/JPCL

    E-Print Network [OSTI]

    Borguet, Eric

    of the fundamental questions that arises from our previous work is whether it is the presence of the electric field, 1353­1358 LETTER pubs.acs.org/JPCL Effect of Electric Fields on the Ultrafast Vibrational Relaxation of Water at a Charged SolidÀLiquid Interface as Probed by Vibrational Sum Frequency Generation Ali

  14. Low frequency phase signal measurement with high frequency squeezing

    E-Print Network [OSTI]

    Zehui Zhai; Jiangrui Gao

    2011-08-24

    We calculate the utility of high-frequency squeezed-state enhanced two-frequency interferometry for low-frequency phase measurement. To use the high-frequency sidebands of the squeezed light, a two-frequency intense laser is used in the interferometry instead of a single-frequency laser as usual. We find that the readout signal can be contaminated by the high-frequency phase vibration, but this is easy to check and avoid. A proof-of-principle experiment is in the reach of modern quantum optics technology.

  15. Dual frequency optical cavity

    DOE Patents [OSTI]

    George, E. Victor (Livermore, CA); Schipper, John F. (Palo Alto, CA)

    1985-01-01

    Method and apparatus for generating two distinct laser frequencies in an optical cavity, using a "T" configuration laser cavity and means for intermittently increasing or decreasing the index of refraction n of an associated transmission medium in one arm of the optical cavity to enhance laser action in one arm or the second arm of the cavity.

  16. Ashtekar's variables without spin

    E-Print Network [OSTI]

    Thomas Schucker

    2009-06-26

    Ashtekar's variables are shown to arise naturally from a 3+1 split of general relativity in the Einstein-Cartan formulation. Thereby spinors are exorcised.

  17. Measurement of the ac Stark shift with a guided matter-wave interferometer

    E-Print Network [OSTI]

    Deissler, B; Burke, J H T; Sackett, C A

    2007-01-01

    We demonstrate the effectiveness of a guided-wave Bose-Einstein condensate interferometer for practical measurements. Taking advantage of the large arm separations obtainable in our interferometer, the energy levels of the 87Rb atoms in one arm of the interferometer are shifted by a calibrated laser beam. The resulting phase shifts are used to determine the ac polarizability at a range of frequencies near and at the atomic resonance. The measured values are in good agreement with theoretical expectations. However, we observe a broadening of the transition near the resonance, an indication of collective light scattering effects. This nonlinearity may prove useful for the production and control of squeezed quantum states.

  18. Frequency Control Performance Measurement and Requirements

    E-Print Network [OSTI]

    Illian, Howard F.

    2011-01-01

    DCS only measured low-frequency disturbances instead of bothlow- and high-frequency disturbances. The DCS requiredof the pre-disturbance frequency and the settling frequency.

  19. Impact of Salt Purity on Interfacial Water Organization Revealed by Conventional and Heterodyne-Detected Vibrational Sum Frequency

    E-Print Network [OSTI]

    Impact of Salt Purity on Interfacial Water Organization Revealed by Conventional and Heterodyne of the chosen salts and their solutions. This is true not only for the ACS grade salts but also vibrational sum frequency generation (VSFG) and heterodyne-detected VSFG (HD-VSFG) spectroscopy that salt

  20. Frequency dispersion of nonlinear response of thin superconducting films in the Berezinskii-Kosterlitz-Thouless state

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

    Dietrich, Scott; Mayer, William; Byrnes, Sean; Vitkalov, Sergey; Sergeev, A.; Bollinger, Anthony T.; Božovi?, Ivan

    2015-02-20

    The effects of microwave radiation on transport properties of atomically thin La2-xSrxCuO? films were studied in the 0.1-20 GHz frequency range. Resistance changes induced by microwaves were investigated at different temperatures (8–15 K) near the superconducting transition. A strong decrease of the nonlinear response is observed within a few GHz of a cutoff frequency ?cut ? 2GHz. The expected frequency dependence vastly underestimates the sharpness of this drop. Numerical simulations that assume ac response to follow dc V-I characteristics of the films reproduce well the low frequency behavior, but fail above ?cut. Thus, high-frequency radiation is much less effective inmore »inducing vortex-antivortex dissociation in the oscillating superconducting condensate.« less

  1. High frequency reference electrode

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-05-31

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or halo' at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes. 4 figs.

  2. High frequency reference electrode

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1994-01-01

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or "halo" at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes.

  3. Electrodeposition of Au/Ag bimetallic dendrites assisted by Faradaic AC-electroosmosis flow

    SciTech Connect (OSTI)

    Ji, Jianlong; Li, Pengwei; Sang, Shengbo, E-mail: sbsang@tyut.edu.cn; Zhang, Wendong, E-mail: wdzhang@tyut.edu.cn; Li, Gang; Hu, Jie [Micro and Nano-system Research Centre, College of Information Engineering, Taiyuan University of Technology, 030024, Taiyuan (China)] [Micro and Nano-system Research Centre, College of Information Engineering, Taiyuan University of Technology, 030024, Taiyuan (China); Zhou, Zhaoying, E-mail: zhouzy@mail.tsinghua.edu.cn; Yang, Xing; Dong, Hualai [MEMS Laboratory, Department of Precision Instruments, Tsinghua University, 100084, Beijing (China)] [MEMS Laboratory, Department of Precision Instruments, Tsinghua University, 100084, Beijing (China)

    2014-03-15

    Au/Ag bimetallic dendrites were synthesized successfully from the corresponding aqueous solution via the AC electrodeposition method. Both of the morphologies and compositions could be tuned by the electrolyte concentration and AC frequency. The prepared bimetallic dendrites were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), transmission electron microscopy (TEM) and UV–vis spectroscopy. The underlying dendrite growth mechanism was then proposed in the context of the Directed Electrochemical Nanowires Assembly (DENA) models. Owing to the unscreened voltage dropping in the electrolyte bulk, electromigration dominates the species flux process, and cations tend to accumulate in areas with strong electric field intensity, such as electrode edges. Moreover, Faradaic AC-electro-osmosis (ACEO) flow could increase the effective diffusion layer thickness in these areas during the electrochemical reaction, and leads to dendrite growth. Further Micro-Raman observations illustrated that the Au/Ag bimetallic dendrites exhibited pronounced surface-enhanced Raman scattering (SERS) activity, using 4-mercaptopyridine (4-MP) as model molecules.

  4. ac-driven atomic quantum motor

    E-Print Network [OSTI]

    A. V. Ponomarev; S. Denisov; P. Hanggi

    2009-06-09

    We invent an ac-driven quantum motor consisting of two different, interacting ultracold atoms placed into a ring-shaped optical lattice and submerged in a pulsating magnetic field. While the first atom carries a current, the second one serves as a quantum starter. For fixed zero-momentum initial conditions the asymptotic carrier velocity converges to a unique non-zero value. We also demonstrate that this quantum motor performs work against a constant load.

  5. r XXXX American Chemical Society A dx.doi.org/10.1021/ac102566f |Anal. Chem. XXXX, XXX, 000000 pubs.acs.org/ac

    E-Print Network [OSTI]

    Bashir, Rashid

    to such methods because it is a noncontact method of heating using microwave energy that is delivered directly­000 ARTICLE pubs.acs.org/ac Silicon Field Effect Transistors as Dual-Use Sensor-Heater Hybrids Bobby Reddy, Jr demonstrate the temperature mediated applications of a previously proposed novel localized dielectric heating

  6. 6/26/12 ACS Applied Materials & Interfaces: Most Read Articles (ACS Publications) 1/3pubs.acs.org/action/showMostReadArticles?journalCode=aamick

    E-Print Network [OSTI]

    Aksay, Ilhan A.

    .org/action/showMostReadArticles?journalCode=aamick Advertisements Info for Advertisers Browse By Issue Select Decade Select Volume Select Issue Advertisements Info. Sreekumaran Nair, Peng Shengjie, Yang Shengyuan, and Seeram Ramakrishna Synthesis of Natural Cellulose Legacy Archives ACS Mobile Video User Resources About Us ACS Members Librarians Authors & Reviewers

  7. Grid regulation services for energy storage devices based on grid frequency

    SciTech Connect (OSTI)

    Pratt, Richard M; Hammerstrom, Donald J; Kintner-Meyer, Michael C.W.; Tuffner, Francis K

    2013-07-02

    Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

  8. Grid regulation services for energy storage devices based on grid frequency

    DOE Patents [OSTI]

    Pratt, Richard M; Hammerstrom, Donald J; Kintner-Meyer, Michael C.W.; Tuffner, Francis K

    2014-04-15

    Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

  9. Controlling high-frequency collective electron dynamics via single-particle complexity

    E-Print Network [OSTI]

    N. Alexeeva; M. T. Greenaway; A. G. Balanov; O. Makarovsky; A. Patanè; M. B. Gaifullin; F. Kusmartsev; T. M. Fromhold

    2012-07-21

    We demonstrate, through experiment and theory, enhanced high-frequency current oscillations due to magnetically-induced conduction resonances in superlattices. Strong increase in the ac power originates from complex single-electron dynamics, characterized by abrupt resonant transitions between unbound and localized trajectories, which trigger and shape propagating charge domains. Our data demonstrate that external fields can tune the collective behavior of quantum particles by imprinting configurable patterns in the single-particle classical phase space.

  10. Micro helical polymeric structures produced by variable voltage direct electrospinning

    E-Print Network [OSTI]

    S. P. Shariatpanahi; A. Iraji zad; I. Abdollahzadeh; R. Shirsavar; D. Bonn; R. Ejtehadi

    2011-09-12

    Direct near field electrospinning is used to produce very long helical polystyrene microfibers in water. The pitch length of helices can be controlled by changing the applied voltage, allowing to produce both micro springs and microchannels. Using a novel high frequency variable voltage electrospinning method we found the helix formation speed and compared the experimental buckling frequency to theoretical expressions for viscous and elastic buckling. Finally we showed that the newmethod can be used to produce new periodic micro and nano structures.

  11. POOL BOILING OF HIGH-FREQUENCY CONDUCTORS

    SciTech Connect (OSTI)

    Wright, S. E. (Spencer E.); Konecni, S. (Snezana); Ammerman, C. N. (Curtt N.); Sims, J. R. (James R.)

    2001-01-01

    This study presents development of a unique, powerful method for cooling high-frequency, AC conductors that can benefit end users of transformer windings, electrical machine windings, and magnet coils. This method of heat removal involves boiling a dielectric, fluorinert refrigerant that is in direct contact with litz wire conductors. A pool boiling test vessel is constructed, which provides for temperature control of the pool of fluorinert liquid. The test vessel is fitted with viewing ports so that the experiments are observed and studied with the aid of high-speed photography. Tests are performed on a variety of litz wire conductors. The boiling heat transfer coefficient is dependent on the conductor surface roughness. The size of the features on the conductor surface depends on the single-strand wire gage from which the conductor is constructed. All tests are performed with the conductors mounted horizontally. These tests are performed using a DC power supply. The results of these experiments will aid in the design of future cooling systems.

  12. 340 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 52, NO. 2, APRIL 2005 Continuous and Discrete Variable-Structure Controls

    E-Print Network [OSTI]

    Mazumder, Sudip K.

    340 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 52, NO. 2, APRIL 2005 Continuous and Discrete- allel multiphase converter either has a transformer at the ac side [7], [8], [10] or uses separate power-frequency transformer and the additional power supplies. A recent approach to overcome these problems is to directly

  13. Solar Electric Grid Integration - Advanced Concepts (SEGIS-AC...

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

    Solar Electric Grid Integration - Advanced Concepts (SEGIS-AC) program, DOE is funding solar projects that are targeting ways to develop power electronics and build smarter, more...

  14. University Policy No.: AC1110 Classification: Academic and Students

    E-Print Network [OSTI]

    Victoria, University of

    University Policy No.: AC1110 Classification: Academic and Students EDUCATIONAL SERVICE services and includes: · Development of educational materials in any form, including digital · Management

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

    E-Print Network [OSTI]

    Victoria, University of

    University Policy No.: AC1145 Classification: Academic and Students Approving Authority, interdisciplinary programs, divisions, and the library) will undergo a review every five to seven years

  16. University Policy No.: AC1150 Classification: Academic and Students

    E-Print Network [OSTI]

    Victoria, University of

    University Policy No.: AC1150 Classification: Academic and Students TEACHING, portfolios, references, library resources, laboratories and equipment) related to the subject matter

  17. Non-vanishing ponderomotive AC electrophoretic effect for particle trapping

    SciTech Connect (OSTI)

    Guan, Weihau; Park, Jae Hyun nmn; Krstic, Predrag S; Reed, Mark A

    2011-01-01

    We present here a study on overlooked aspects of alternating current (AC) electrokinetics AC electrophoretic (ACEP) phenomena. The dynamics of a particle with both polarizability and net charges in a non-uniform AC electric trapping field is investigated. It is found that either electrophoretic (EP) or dielectrophoretic (DEP) effects can dominate the trapping dynamics, depending on experimental conditions. A dimensionless parameter gamma is developed to predict the relative strength of EP and DEP effects in a quadrupole AC field. An ACEP trap is feasible for charged particles in salt-free or low salt concentration solutions. In contrast to DEP traps, an ACEP trap favors the downscaling of the particle size.

  18. Theresa Windus elected ACS Physical Chemistry Division Councilor...

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

    Theresa Windus elected ACS Physical Chemistry Division Councilor Congratulations to Ames Laboratory faculty scientist Theresa Windus who has been elected Councilor to the Physical...

  19. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; William A. Smith; Garold L. Gresham; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that due to inherent species variabilities, production conditions, and differing harvest, collection, and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture, and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  20. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; Garold L. Gresham; William A. Smith; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per-ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that, due to inherent species variabilities, production conditions and differing harvest, collection and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  1. Frequency-dependent electrostatic actuation in microfluidic MEMS.

    SciTech Connect (OSTI)

    Zavadil, Kevin Robert; Michalske, Terry A.; Sounart, Thomas L.

    2003-09-01

    Electrostatic actuators exhibit fast response times and are easily integrated into microsystems because they can be fabricated with standard IC micromachining processes and materials. Although electrostatic actuators have been used extensively in 'dry' MEMS, they have received less attention in microfluidic systems probably because of challenges such as electrolysis, anodization, and electrode polarization. Here we demonstrate that ac drive signals can be used to prevent electrode polarization, and thus enable electrostatic actuation in many liquids, at potentials low enough to avoid electrochemistry. We measure the frequency response of an interdigitated silicon comb-drive actuator in liquids spanning a decade of dielectric permittivities and four decades of conductivity, and present a simple theory that predicts the characteristic actuation frequency. The analysis demonstrates the importance of the native oxide on silicon actuator response, and suggests that the actuation frequency can be shifted by controlling the thickness of the oxide. For native silicon devices, actuation is predicted at frequencies less than 10 MHz, in electrolytes of ionic strength up to 100 mmol/L, and thus electrostatic actuation may be feasible in many bioMEMS and other microfluidic applications.

  2. Frequency mixing crystal

    DOE Patents [OSTI]

    Ebbers, Christopher A. (Livermore, CA); Davis, Laura E. (Manteca, CA); Webb, Mark (Salida, CA)

    1992-01-01

    In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmoic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X.sub.2 Y(NO.sub.3).sub.5 .multidot.2 nZ.sub.2 o wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

  3. Frequency doubling crystals

    DOE Patents [OSTI]

    Wang, Francis (Danville, CA); Velsko, Stephan P. (Livermore, CA)

    1989-01-01

    A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a "harmonic generating unit" which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.

  4. Radio frequency coaxial feedthrough

    DOE Patents [OSTI]

    Owens, Thomas L. (Kingston, TN)

    1989-01-17

    An improved radio frequency coaxial transmission line vacuum feed-through provided based on the use of a half-wavelength annular dielectric pressure barrier disk, or multiple disks comprising an effective half wavelength structure to eliminate reflections from the barrier surfaces. Gas-tight seals are formed about the outer and inner diameter surfaces of the barrier disk using a sealing technique which generates radial forces sufficient to form seals by forcing the conductor walls against the surfaces of the barrier disks in a manner which does not deform the radii of the inner and outer conductors, thereby preventing enhancement of the electric field at the barrier faces which limits voltage and power handling capabilities of a feedthrough.

  5. Flying radio frequency undulator

    SciTech Connect (OSTI)

    Kuzikov, S. V.; Vikharev, A. A. [Institute of Applied Physics, Russian Academy of Sciences, 46 Ulyanov St., Nizhny Novgorod 603950 (Russian Federation); Savilov, A. V. [Institute of Applied Physics, Russian Academy of Sciences, 46 Ulyanov St., Nizhny Novgorod 603950 (Russian Federation); Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod (Russian Federation)

    2014-07-21

    A concept for the room-temperature rf undulator, designed to produce coherent X-ray radiation by means of a relatively low-energy electron beam and pulsed mm-wavelength radiation, is proposed. The “flying” undulator is a high-power short rf pulse co-propagating together with a relativistic electron bunch in a helically corrugated waveguide. The electrons wiggle in the rf field of the ?1st spatial harmonic with the phase velocity directed in the opposite direction in respect to the bunch velocity, so that particles can irradiate high-frequency Compton's photons. A high group velocity (close to the speed of light) ensures long cooperative motion of the particles and the co-propagating rf pulse.

  6. High frequency nanotube oscillator

    DOE Patents [OSTI]

    Peng, Haibing (Houston, TX); Zettl, Alexander K. (Kensington, TX)

    2012-02-21

    A tunable nanostructure such as a nanotube is used to make an electromechanical oscillator. The mechanically oscillating nanotube can be provided with inertial clamps in the form of metal beads. The metal beads serve to clamp the nanotube so that the fundamental resonance frequency is in the microwave range, i.e., greater than at least 1 GHz, and up to 4 GHz and beyond. An electric current can be run through the nanotube to cause the metal beads to move along the nanotube and changing the length of the intervening nanotube segments. The oscillator can operate at ambient temperature and in air without significant loss of resonance quality. The nanotube is can be fabricated in a semiconductor style process and the device can be provided with source, drain, and gate electrodes, which may be connected to appropriate circuitry for driving and measuring the oscillation. Novel driving and measuring circuits are also disclosed.

  7. The variable star population in Phoenix: coexistence of Anomalous and short-period Classical Cepheids, and detection of RR Lyrae variables

    E-Print Network [OSTI]

    C. Gallart; A. Aparicio; W. L. Freedman; B. F. Madore; D. Martinez-Delgado; P. B. Stetson

    2004-02-17

    We present the results of a search for variable stars in the Local Group dwarf galaxy Phoenix. Nineteen Cepheids, six candidate long-period variables, one candidate eclipsing binary and a large number of candidate RR Lyrae stars have been identified. Periods and light curves have been obtained for all the Cepheid variables. Their distribution in the period-luminosity diagram reveals that both Anomalous Cepheids (AC) and short-period Classical Cepheids s-pCC are found in our sample. This is the first time that both types of variable star are identified in the same system even though they likely coexist, but have gone unnoticed so far, in other low-metallicity galaxies like Leo A and Sextans A. We argue that the conditions for the existence of both types of variable star in the same galaxy are a low metallicity at all ages, and the presence of both young and intermediate-age (or old, depending on the nature of AC) stars. The RR Lyrae candidates trace, together with the well developed horizontal branch, the existence of an important old population in Phoenix. The different spatial distributions of s-pCC, AC and RR Lyrae variables in the Phoenix field are consistent with the stellar population gradients found in Phoenix, in the sense that the younger population is concentrated in the central part of the galaxy. The gradients in the distribution of the young population within the central part of Phoenix, which seem to indicate a propagation of the recent star formation, are also reflected in the spatial distribution of the s-pCC.

  8. AVTA: ChargePoint AC Level 2 Charging System Testing Results...

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

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

  9. , : roym@ee.technion.ac.il -OpenStack

    E-Print Network [OSTI]

    Cidon, Israel

    (OVS) . , , . OpenFlow. #12; OpenFlow and SDN Emulating Data-Centers by MiniNet : yanivbi@tx.technion.ac.il ( Data , . Topology Verification in OpenFlow datacenter networks : yanivbi@tx.technion.ac.il Datacenter. , mininet datacenter , " . -datacenter , Openflow. 2

  10. www.swansea.ac.uk/artsandhumanities Arts and Humanities

    E-Print Network [OSTI]

    Martin, Ralph R.

    dissertation or design a research project of their own (with 10,000 word report) which draws on issues Email: rhys.jones@swansea.ac.uk www.swansea.ac.uk/mediastudies/admissions - The Potter Guide to Higher relations, humanities, social science, computer science or related background. Professionals interested

  11. 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 in islanded ac microgrids with both synchronous generators and inverter-interfaced power supplies. Although they are smaller and have lower ratings, the generation control objectives for an islanded microgrid are similar

  12. ACADEMIC PLAN ENGAE-AC OLD CURRICULUM CODE_388_

    E-Print Network [OSTI]

    Qiu, Weigang

    ACADEMIC PLAN ENGAE-AC OLD CURRICULUM CODE_388_ DEGREE CODE _40 Hunter College of the City. Student's Signature Date ____________________ #12;ACADEMIC PLAN ENGAE-AC OLD CURRICULUM CODE_388_ DEGREE Study of Young Adult Literature in Our Diverse Society 3 Fall Spring Summer SEDC 720 Adolescent- Health

  13. Undergraduate study 2016 www.nottingham.ac.uk/psychology

    E-Print Network [OSTI]

    Qu, Rong

    Psychology Undergraduate study 2016 www.nottingham.ac.uk/psychology For general undergraduate: www.nottingham.ac.uk/faqs #12;Contents Welcome to the School of Psychology Psychology of conflicts, accidents and mental disorders. The University of Nottingham's School of Psychology is one

  14. Aircraft AC Generators: Hybrid System Modeling and Simulation

    E-Print Network [OSTI]

    Koutsoukos, Xenofon D.

    generator, phase-domain model, synchronous AC generator. I. INTRODUCTION The Integrated Drive Generator (IDG1 Aircraft AC Generators: Hybrid System Modeling and Simulation Ashraf Tantawy, Student Member--Integrated Drive Generators (IDGs) are the main source of electrical power for a number of critical systems

  15. 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

  16. www.le.ac.uk/physics UNDERGRADUATE COURSES IN

    E-Print Network [OSTI]

    Banaji,. Murad

    www.le.ac.uk/physics UNDERGRADUATE COURSES IN Physics and Astronomy Department of Physics and Astronomy #12;www.le.ac.uk/physics-ug "The Leicester Department of Physics and Astronomy offers superb courses. Students get a broader exposure to different areas of physics and astronomy than is possible

  17. Modeling, analysis and simulation of "AC inductor" based converters

    E-Print Network [OSTI]

    for current sourcing applications, such as battery chargers, where differences between the average input.g. 2-8]. II. LARGE SIGNAL ANALYSIS OF THE "AC INDUCTOR" BASED CHARGERS To describe the behavior of AC inductor topologies, we first consider the non-isolated charger shown in Fig. 1. Isolation can be obtained

  18. International Student Guide www.swansea.ac.uk/geography

    E-Print Network [OSTI]

    Harman, Neal.A.

    International Student Guide Geography www.swansea.ac.uk/geography www.swansea.ac.uk/science/international #12;Reasons to study at Swansea University Geography at Swansea University Established in 1920, 36th and more Over 15,000 students / Over 2,000 International students Rated as one of the top 20 Geography

  19. European Student Guide www.swansea.ac.uk/geography

    E-Print Network [OSTI]

    Harman, Neal.A.

    European Student Guide Geography www.swansea.ac.uk/geography www.swansea.ac.uk/science/international #12;Reasons to study at Swansea University Geography at Swansea University Established in 1920, 36th and more Over 15,000 students / Over 2,000 International students Rated as one of the top 20 Geography

  20. Variable Refrigerant Flow HVAC 

    E-Print Network [OSTI]

    Jones, S.

    2013-01-01

    Variable refrigerant flow technology HVAC CATEE 2013 San Antonio, TX ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio, Texas Dec. 16-18 What is the acronym VRF? ? Variable Refrigerant Flow Operates like a... heat pump utilizing VFD Inverter Compressors and LEV’s Unlike conventional commercial and residential HVAC systems in the USA The predominate method of cooling and heating in the world ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency...

  1. 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

  2. Long-Term Wind Power Variability

    SciTech Connect (OSTI)

    Wan, Y. H.

    2012-01-01

    The National Renewable Energy Laboratory started collecting wind power data from large commercial wind power plants (WPPs) in southwest Minnesota with dedicated dataloggers and communication links in the spring of 2000. Over the years, additional WPPs in other areas were added to and removed from the data collection effort. The longest data stream of actual wind plant output is more than 10 years. The resulting data have been used to analyze wind power fluctuations, frequency distribution of changes, the effects of spatial diversity, and wind power ancillary services. This report uses the multi-year wind power data to examine long-term wind power variability.

  3. Variable thrust cartridge

    DOE Patents [OSTI]

    Taleyarkhan, Rusi P. (Knoxville, TN)

    2000-11-07

    The present invention is a variable thrust cartridge comprising a water-molten aluminum reaction chamber from which a slug is propelled. The cartridge comprises a firing system that initiates a controlled explosion from the reaction chamber. The explosive force provides a thrust to a slug, preferably contained within the cartridge.

  4. 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

    1982-09-01

    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.

  5. 26.1 / M. Doshi 26.1: Low-Frequency Square-Wave Drive for Large Screen LCD-TV

    E-Print Network [OSTI]

    at Boulder, Boulder, CO-80309 0425 Francisco J. Azcondo Electronics Technology, Systems and Automation, Spain Abstract This paper presents a low-frequency square-wave drive, consisting of a single high accurate lamp current regulation. Key to the architecture is a proposed capacitive coupling approach for ac

  6. Acoustic resonance frequency locked photoacoustic spectrometer

    DOE Patents [OSTI]

    Pilgrim, Jeffrey S.; Bomse, David S.; Silver, Joel A.

    2003-09-09

    A photoacoustic spectroscopy method and apparatus for maintaining an acoustic source frequency on a sample cell resonance frequency comprising: providing an acoustic source to the sample cell, the acoustic source having a source frequency; repeatedly and continuously sweeping the source frequency across the resonance frequency at a sweep rate; and employing an odd-harmonic of the source frequency sweep rate to maintain the source frequency sweep centered on the resonance frequency.

  7. Determination of station blackout frequency-duration relationships

    SciTech Connect (OSTI)

    Griggs, D.P.; Riggs, B.K.; Balakrishna, S.

    1986-01-01

    Station blackout is the loss of all alternating current (ac) power to the essential and nonessential electrical buses in a nuclear power plant. This generally involves the loss of redundant off-site power sources and the failure of two or more emergency diesel generators (EDGs). The US Nuclear Regulatory Commission (NRC) has proposed requiring all commercial reactors to have the capability of coping with a station blackout of a specified duration. The NRC has also proposed 4 or 8 h as acceptable durations, depending on plant susceptibility to the occurrence of station blackout events. Analyses were performed to determine expected station blackout frequencies representative of a majority of domestic nuclear power plants. A methodology based on that developed by the NRC was used. Representative industry data for loss of off-site power (LOOP) events and EDG reliability were used in the analyses.

  8. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  9. Variable laser attenuator

    DOE Patents [OSTI]

    Foltyn, S.R.

    1987-05-29

    The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

  10. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

    1996-01-01

    A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

  11. Transparency in nonlinear frequency conversion

    E-Print Network [OSTI]

    Longhi, Stefano

    2015-01-01

    Suppression of wave scattering and the realization of transparency effects in engineered optical media and surfaces have attracted great attention in the past recent years. In this work the problem of transparency is considered for optical wave propagation in a nonlinear dielectric medium with second-order $\\chi^{(2)}$ susceptibility. Because of nonlinear interaction, a reference signal wave at carrier frequency $\\omega_1$ can exchange power, thus being amplified or attenuated,when phase matching conditions are satisfied and frequency conversion takes place. Therefore, rather generally the medium is not transparent to the signal wave because of 'scattering' in the frequency domain. Here we show that broadband transparency, corresponding to the full absence of frequency conversion in spite of phase matching, can be observed for the signal wave in the process of sum frequency generation whenever the effective susceptibility $\\chi^{(2)}$ along the nonlinear medium is tailored following a suitable spatial apodiza...

  12. Aalborg Universitet Power flow analysis for droop controlled LV hybrid AC-DC microgrids with virtual

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Power flow analysis for droop controlled LV hybrid AC-DC microgrids controlled LV hybrid AC-DC microgrids with virtual impedance. In Proceedings of the IEEE Power & Energy Interlinking converter PV WT IBS DC microgrid DC microgrid AC microgrid AC Load Figure 1. Structure

  13. 08853010/$25.00 2009 ieee 1301ieee transactions on ultrasonics, ferroelectrics, and frequency control, vol. 56, no. 7, july 2009

    E-Print Network [OSTI]

    Smith, Stephen

    a variable ac generator (Variac) to produce a vibration in the length of the needle fragment. a 60-Hz Variac by a transverse f. W. Bell Gauss/tesla Meter Model 5080 (orlando, fl). fig. 2(a) shows a real time 3-d rendered

  14. Role of Climate Variability in Modulating the Surface Water and Groundwater Interaction

    E-Print Network [OSTI]

    Arumugam, Sankar

    levels with El Niño/ Southern Oscillation (ENSO) index, NINO3.4, shows that interannual variability between JAS groundwater levels and JAS NINO3.4 is not statistically significant. Precipitation forecasts exists on the association between low-frequency climatic variability [e.g., El Niño/Southern Oscillation

  15. Sustainable Developmentwww.st-andrews.ac.uk/sasi

    E-Print Network [OSTI]

    Brierley, Andrew

    108 Sustainable Developmentwww.st-andrews.ac.uk/sasi Sustainable Development Degree options MSc (One Year) Coursework & 15,000-word Dissertation Sustainable Development MSc (Two Years) Coursework Sustainable Development Postgraduate Certificate (One Semester) Coursework Sustainable Development MRes (One

  16. 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

  17. Adjustable Speed AC Motor Drives-Applications Problems 

    E-Print Network [OSTI]

    Enjeti, P.

    1997-01-01

    Adjustable speed AC drives have become the preferred choice in many industrial applications where controlled speed is required. At the same time, the maturing of the technology and the availability of fast and efficient ...

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

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

    provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the...

  19. 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

  20. Bond graph models of electromechanical systems. The AC generator case

    E-Print Network [OSTI]

    Batlle, Carles

    Bond graph models of electromechanical systems. The AC generator case Carles Batlle Department. After reviewing electromechanical energy conversion and torque gener- ation, the core element present in any electromechanical system is introduced, and the corresponding electrical and mechanical ports

  1. DE-AC05-00OR22800

    National Nuclear Security Administration (NNSA)

    DE-AC05-00OR22800 DOE DIRECTIVES DOE Directives can be found at the following Internet address: https:www.directives.doe.gov REQUIRED COMPLIANCE DOCUMENT DATE TITLE...

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

    E-Print Network [OSTI]

    Kent, University of

    System website: www.kent.ac.uk/cmsds-local/ Installing Putty Download it from the web 1. www close to each other. A dark cursor will not show on a dark background. Ideally make either

  3. November 2013 www.kent.ac.uk/library

    E-Print Network [OSTI]

    Banaji,. Murad

    November 2013 www.kent.ac.uk/library Information Services Templeman Library SCONUL Access scheme) to the Templeman Library. I am a registered member of the Sconul Access scheme and hold a valid card. If given ............................... ................................................................................................................ Home library

  4. Micro-scale piezoelectric vibration energy harvesting: from fixed-frequency to adaptable-frequency devices

    E-Print Network [OSTI]

    Miller, Lindsay Margaret

    2012-01-01

    36] Eli Leland. A MEMS sensor for AC electric current. PhDof mems piezoelectric vibration harvesters. Sensors anda mems generator and a power management circuit. Sensors and

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

    SciTech Connect (OSTI)

    Suparna Kadam; Miles Russell

    2012-06-15

    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.

  6. Improving the homogeneity of alternating current-drive atmospheric pressure dielectric barrier discharges in helium with an additional low-amplitude radio frequency power source: A numerical study

    SciTech Connect (OSTI)

    Wang Qi [Dalian Institute of Semiconductor Technology, School of Electronics Science and Technology, Dalian University of Technology, Dalian 116023 (China); Sun Jizhong; Zhang Jianhong; Wang Dezhen [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China); Liu Liying [Department of Electrical Engineering, Shenyang Institute of Engineering, Shenyang 110136 (China)

    2013-04-15

    It was proposed in this paper that the homogeneity of the atmospheric pressure discharge driven by an ac power source could be improved by applying an auxiliary low-amplitude rf power source. To verify the idea, a two-dimensional fluid model then was applied to study the atmospheric discharges in helium driven by ac power, low-amplitude rf power, and combined ac and low-amplitude rf power, respectively. Simulation results confirmed that an auxiliary rf power could improve the homogeneity of a discharge driven by an ac power source. It was further found that there existed a threshold voltage of the rf power source leading to the transition from inhomogeneous to homogeneous discharge. As the frequency of the rf power source increased from 2 to 22 MHz, the magnitude of the threshold voltage dropped first rapidly and then to a constant value. When the frequency was over 13.56 MHz, the magnitude of the threshold voltage was smaller than one-sixth of the ac voltage amplitude under the simulated discharge parameters.

  7. An ultra low-noise AC beam transformer and digital signal processing system for CERN's ELENA ring

    E-Print Network [OSTI]

    Angoletta, M E; Caspers, F; Federmann, S; Molendijk, J; Pedersen, F; Sanchez-Quesada, J

    2013-01-01

    CERN’s Extra Low ENergy Antiproton (ELENA) ring is a new synchrotron that will be commissioned in 2016 to further decelerate the antiprotons coming from CERN’s Antiproton Decelerator (AD). Essential longitudinal diagnostics required for commissioning and operation include the intensity measurement for bunched and debunched beams and the measurement of p/p for debunched beams to assess the electron cooling performance. The beam phase information is also needed by the Low-Level RF (LLRF) system. The baseline system for providing the required beam parameters and signals is based upon two ultra-low-noise AC beam transformers and associated digital signal processing. The AC beam transformers cover different frequency regions and are an adaptation to the ELENA layout of those used in the AD. Two AC beam transformers will also be installed in the extraction lines to provide beam intensity measurements. The digital signal processing will be carried out with the leadingedge hardware family used for ELENA’s L...

  8. Blazar Variability and Evolution in the GeV Regime

    E-Print Network [OSTI]

    Tsujimoto, S; Nishijima, K; Kodani, K

    2015-01-01

    One of the most important problem of the blazar astrophysics is to understand the physical origin of the blazar sequence. In this study, we focus on the GeV gamma-ray variability of blazars and evolution perspective we search the relation between the redshift and the variability amplitude of blazars for each blazar subclass. We analyzed the Fermi-LAT data of the TeV blazars and the bright AGNs (flux $\\geq$ 4$\\times10^{-9}$ cm$^{-2}$s$^{-1}$) selected from the 2LAC (the 2nd LAT AGN catalog) data base. As a result, we found a hint of the correlation between the redshift and the variability amplitude in the FSRQs. Furthermore the BL Lacs which have relatively lower peak frequency of the synchrotron radiation and relatively lower redshift, have a tendency to have a smaller variability amplitude.

  9. AUTO ID FUTURE - FREQUENCY AGNOSTIC

    E-Print Network [OSTI]

    DATTA, SHOUMEN

    Identification of information is one key to the development of intelligent decision systems of the future. Frequency agnostic automatic identification is only one step in the physical world to make physical objects identify ...

  10. Microwave and Radio Frequency Workshop

    Broader source: Energy.gov [DOE]

    At the Microwave and Radio Frequency Workshop (held in Long Beach, CA, on July 25, 2012), academic and industry experts discussed the existing and emerging electrotechnologies – such as microwave ...

  11. http://www-cr.scphys.kyoto-u.ac.jp/gakubu/P6.html http://www-cr.scphys.kyoto-u.ac.jp/gakubu/P6.html

    E-Print Network [OSTI]

    2011 P6 http://www-cr.scphys.kyoto-u.ac.jp/gakubu/P6.html web #12;http://www-cr.scphys.kyoto-u.ac.jp/gakubu/P6.html () ( #12;http://www-cr.scphys.kyoto-u.ac.jp/gakubu/P6.html X MeV X Astro-H 2013 TeV10m) #12;http://www-cr.scphys.kyoto-u.ac.jp/gakubu/P6.html 2010 ASTRO-H CCD X (2) () (2) (2

  12. cwnam@netlab.snu.ac.kr {jinyo.chung, yongsuk}@samsung.com sbahk@netlab.snu.ac.kr Detection of Alien Piconet using Preamble Information

    E-Print Network [OSTI]

    Bahk, Saewoong

    @netlab.snu.ac.kr Detection of Alien Piconet using Preamble Information Changwon Nam*, Jinyong Chung+, Yongsuk Kim+, Saewoong

  13. Holocene flood frequency across the Central Alps e solar forcing and evidence for variations in North Atlantic atmospheric circulation

    E-Print Network [OSTI]

    Gilli, Adrian

    Holocene flood frequency across the Central Alps e solar forcing and evidence for variations Available online Keywords: Alps Lake sediments Heavy precipitation Flood reconstruction Solar forcing NAO the past natural variability of floods caused by heavy precipitation constitutes important input

  14. Frequency regulator for synchronous generators

    DOE Patents [OSTI]

    Karlicek, R.F.

    1982-08-10

    The present invention is directed to a novel frequency regulator which controls a generator output frequency for variations in both the input power to the generator and the power supplied to an uncontrolled external load. The present invention further includes over current and current balance protection devices which are relatively inexpensive to manufacture, which may be encapsulated to provide protection from the operating environment and which respond more quickly than previously known electromechanical devices. 11 figs.

  15. Frequency regulator for synchronous generators

    DOE Patents [OSTI]

    Karlicek, Robert F. (1920 Camino Centroloma, Fullerton, CA 92633)

    1982-01-01

    The present invention is directed to a novel frequency regulator which controls a generator output frequency for variations in both the input power to the generator and the power supplied to an uncontrolled external load. The present invention further includes over current and current balance protection devices which are relatively inexpensive to manufacture, which may be encapsulated to provide protection from the operating environment and which respond more quickly than previously known electromechanical devices.

  16. Variable Valve Actuation

    SciTech Connect (OSTI)

    Jeffrey Gutterman; A. J. Lasley

    2008-08-31

    Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the mechanism it was determined that the single cam design did not have enough flexibility to satisfy three critical OEM requirements simultaneously, (maximum valve lift variation, intake valve opening timing and valve closing duration), and a new approach would be necessary. After numerous internal design reviews including several with the OEM a dual cam design was developed that had the flexibility to meet all motion requirements. The second cam added complexity to the mechanism however the cost was offset by the deletion of the electric motor required in the previous design. New patent applications including detailed drawings and potential valve motion profiles were generated and alternate two cam designs were proposed and evaluated for function, cost, reliability and durability. Hardware was designed and built and testing of sample hardware was successfully completed on an engine test stand. The mechanism developed during the course of this investigation can be applied by Original Equipment Manufacturers, (OEM), to their advanced diesel engines with the ultimate goal of reducing emissions and improving fuel economy. The objectives are: (1) Develop an optimal, cost effective, variable valve actuation (VVA) system for advanced low temperature diesel combustion processes. (2) Design and model alternative mechanical approaches and down-select for optimum design. (3) Build and demonstrate a mechanism capable of application on running engines.

  17. Stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Vadnais, Kenneth G. (Ojai, CA); Bashforth, Michael B. (Buellton, CA); Lewallen, Tricia S. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA)

    1994-01-01

    A stepped frequency ground penetrating radar system is described comprising an RF signal generating section capable of producing stepped frequency signals in spaced and equal increments of time and frequency over a preselected bandwidth which serves as a common RF signal source for both a transmit portion and a receive portion of the system. In the transmit portion of the system the signal is processed into in-phase and quadrature signals which are then amplified and then transmitted toward a target. The reflected signals from the target are then received by a receive antenna and mixed with a reference signal from the common RF signal source in a mixer whose output is then fed through a low pass filter. The DC output, after amplification and demodulation, is digitized and converted into a frequency domain signal by a Fast Fourier Transform. A plot of the frequency domain signals from all of the stepped frequencies broadcast toward and received from the target yields information concerning the range (distance) and cross section (size) of the target.

  18. Applications of neural networks and other machine learning techniques. Contact: Neil Davey, n.davey@herts.ac.uk, Yi Sun, y.2.sun@herts.ac.uk

    E-Print Network [OSTI]

    Hertfordshire, University of

    .davey@herts.ac.uk, Yi Sun, y.2.sun@herts.ac.uk We are currently involved in three collaborative projects, investigating. This is a collaboration with our School of Pharmacy. A description of our work can be found at: http://homepages.feis.herts.ac.uk/~nngroup/pubs/papers/Sun

  19. Method and apparatus for generating radiation utilizing DC to AC conversion with a conductive front

    DOE Patents [OSTI]

    Dawson, John M. (Pacific Palisades, CA); Mori, Warren B. (Hermosa Beach, CA); Lai, Chih-Hsiang (So. Pasadena, CA); Katsouleas, Thomas C. (Malibu, CA)

    1998-01-01

    Method and apparatus for generating radiation of high power, variable duration and broad tunability over several orders of magnitude from a laser-ionized gas-filled capacitor array. The method and apparatus convert a DC electric field pattern into a coherent electromagnetic wave train when a relativistic ionization front passes between the capacitor plates. The frequency and duration of the radiation is controlled by the gas pressure and capacitor spacing.

  20. Electric characterization of (Sr, Sr-Ba, Ba) M-type ferrites by AC measurements[Alternating Current

    SciTech Connect (OSTI)

    Huanosta-Tera, A.; Lira-Hueso, R. de; Perez-Orta, O.; Palomares-Sanchez, S.A.; Ponce-Castaneda, S.; Mirabal-Garcia, M.

    2000-02-01

    Considering the electrical conductivity in ceramics, necessary reference should be given to dynamic processes occurring as a function of frequency and temperature. Although the most immediate interest in ferrites lies in their magnetic properties, technological applications require a wider knowledge of general physical properties as well. This is especially applicable when the materials are studied as a function of composition or when adding different modifiers. In this report, the authors present results of the ac and dc electric characteristics of a family of magneto-plumbite-type hexaferrites, where Ba gradually substitutes Sr in the Ba{sub x}Sr{sub 1{minus}x}Fe{sub 12}O{sub 19} compound (0 {le} x {le} 1). The results were determined over a wide range of frequencies and temperatures.

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

    DOE Patents [OSTI]

    Lu, Bin; Habetler, Thomas G; Zhang, Pinjia

    2013-02-26

    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.

  2. Frequency Stability of Atomic Frequency Standards beyond Quantum Projection Noise

    E-Print Network [OSTI]

    G. M. Saxena

    2011-04-07

    In this paper we describe that the optically pumped frequency standards can have frequency stability beyond the quantum noise limit by detecting the Ramsey resonance through the squeezed light. In this paper we report that instead of considering the interaction of entangled atoms in the microwave region, it will be more practical to create the entanglement of the atoms in the detection region using the squeezed light, which is also used for the detection of the Ramsey resonance. The advantage of squeezing can be derived when the technical noises have been removed.

  3. Time-frequency analysis and Harmonic Gaussian Functions

    E-Print Network [OSTI]

    Tokiniaina Ranaivoson; Raoelina Andriambololona; Rakotoson Hanitriarivo

    2013-08-08

    A method for time-frequency analysis is given. The approach utilizes properties of Gaussian distribution, properties of Hermite polynomials and Fourier analysis. We begin by the definitions of a set of functions called harmonic Gaussian functions. Then these functions are used to define a set of transformations,noted T_n, which associate to a function {\\psi},of the time variable t, a set of functions {\\Psi}_n which depend on time, frequency and frequency (or time) standard deviation. Some properties of the transformations T_n and the functions {\\Psi}_n are given. It is proved in particular that the square of the modulus of each function {\\Psi}_n can be interpreted as a representation of the energy distribution of the signal, represented by the function {\\psi}, in the time-frequency plane for a given value of the frequency (or time) standard deviation. It is also shown that the function {\\psi}, can be recovered from the functions{\\Psi}_n.

  4. Low-Frequency Weather and the Emergence of the Climate Department of Physics, McGill University, Montreal, Quebec, Canada

    E-Print Network [OSTI]

    Lovejoy, Shaun

    Low-Frequency Weather and the Emergence of the Climate S. Lovejoy Department of Physics, Mc, Paris, France Météo France, Paris, France We survey atmospheric variability from weather scales up quenched, leading to a scaling "low-frequency weather" regime extending out to c 10­100 years

  5. Decentralized customerlevel under frequency load shedding in...

    Open Energy Info (EERE)

    Decentralized customerlevel under frequency load shedding in Switzerland (Smart Grid Project) Jump to: navigation, search Project Name Decentralized customerlevel under frequency...

  6. Two-frequency Ramsey interferometry

    SciTech Connect (OSTI)

    Seidel, D.; Muga, J. G. [Departmento de Quimica-Fisica, Universidad del Pais Vasco, Apartado Postal 644, 48080 Bilbao (Spain)

    2007-02-15

    We investigate Ramsey interferometry for two separated fields oscillating with different frequencies. It is shown that the interplay between average and relative detuning leads to interference effects not present in the standard, single-frequency setup. For a large free-flight time of ground-state atoms before entering the first field region, the Ramsey fringes with respect to the relative detuning become much narrower than the usual ones. The stability of these effects with respect to phase or velocity fluctuations is discussed.

  7. Radio-frequency power generation

    E-Print Network [OSTI]

    Carter, Richard G

    2013-01-01

    This paper reviews the main types of radio-frequency power amplifiers which are, or may be, used for high-power hadron accelerators. It covers tetrodes, inductive output tubes, klystrons and magnetrons with power outputs greater than 10 kW continuous wave or 100 kW pulsed at frequencies from 50 MHz to 30 GHz. Factors affecting the satisfactory operation of amplifiers include cooling, matching and protection circuits are discussed. The paper concludes with a summary of the state of the art for the different technologies.

  8. Oscillation phenomena of a plasma produced by an AC driven hot cathode

    SciTech Connect (OSTI)

    Takahashi, Yuki; Miyamoto, Naoki; Kasuya, Toshiro; Wada, Motoi

    2012-11-06

    Amplitude of oscillating discharge current has been measured for Bernas-type ion source equipped with an alternating current heated hot tungsten filament cathode. Measurements have been made by changing the filament diameter from 0.2 mm to 0.7 mm, and by changing the DC discharge current from 0.1 A to 1.5 A. The fluctuation amplitude of the discharge current was found decreased as the diameter of the filament was enlarged. The fluctuation amplitude took the minimum value at a frequency from several hundred Hz to 1 kHz depending upon the filament diameter and DC discharge current. For example, the relative oscillation amplitude was the smallest at 1 kHz for 0.7 mm diameter filament. Increase in discharge current had reduced the minimum oscillation amplitude, and increased the frequency at which the oscillating amplitude took the minimum. Fundamental mechanisms relevant to these characteristics of oscillation amplitude of discharge current from an AC driven hot cathode filament are discussed.

  9. Superconducting shielded core reactor with reduced AC losses

    DOE Patents [OSTI]

    Cha, Yung S.; Hull, John R.

    2006-04-04

    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.

  10. Frequency agile optical parametric oscillator

    DOE Patents [OSTI]

    Velsko, S.P.

    1998-11-24

    The frequency agile OPO device converts a fixed wavelength pump laser beam to arbitrary wavelengths within a specified range with pulse to pulse agility, at a rate limited only by the repetition rate of the pump laser. Uses of this invention include Laser radar, LIDAR, active remote sensing of effluents/pollutants, environmental monitoring, antisensor lasers, and spectroscopy. 14 figs.

  11. Frequency agile optical parametric oscillator

    DOE Patents [OSTI]

    Velsko, Stephan P. (Livermore, CA)

    1998-01-01

    The frequency agile OPO device converts a fixed wavelength pump laser beam to arbitrary wavelengths within a specified range with pulse to pulse agility, at a rate limited only by the repetition rate of the pump laser. Uses of this invention include Laser radar, LIDAR, active remote sensing of effluents/pollutants, environmental monitoring, antisensor lasers, and spectroscopy.

  12. Application of Resonant Frequency Eddy Current Technique on a Shot-Peened Nickel-Based Engine-Grade Material

    SciTech Connect (OSTI)

    Ko, Ray T.; Sathish, Shamachary; Boehnlein, Thomas R. [Structural Integrity Division, University of Dayton Research Institute, 300 College Park Drive, Dayton, Ohio 45469-0120 (United States); Blodgett, Mark P. [Metals, Ceramics, and NDE Division, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433 (United States)

    2007-03-21

    The shot peening conditions of a nickel-based engine-grade material were evaluated using a novel eddy current measurement technique. With this technique, the shift of a resonant frequency was found to be dependent on variables which also affect conventional eddy current testing. The cable effect is another important variable, which is often neglected in a routine eddy current testing, is also discussed. Experimental results showed that at high frequencies, the shot peening conditions were easily distinguishable using this frequency shift technique.

  13. Radial Velocity Variability of Field Brown Dwarfs

    E-Print Network [OSTI]

    Prato, L; Rice, E L; McLean, I S; Kirkpatrick, J D; Burgasser, A J; Kim, S S

    2015-01-01

    We present paper six of the NIRSPEC Brown Dwarf Spectroscopic Survey, an analysis of multi-epoch, high-resolution (R~20,000) spectra of 25 field dwarf systems (3 late-type M dwarfs, 16 L dwarfs, and 6 T dwarfs) taken with the NIRSPEC infrared spectrograph at the W. M. Keck Observatory. With a radial velocity precision of ~2 km/s, we are sensitive to brown dwarf companions in orbits with periods of a few years or less given a mass ratio of 0.5 or greater. We do not detect any spectroscopic binary brown dwarfs in the sample. Given our target properties, and the frequency and cadence of observations, we use a Monte Carlo simulation to determine the detection probability of our sample. Even with a null detection result, our 1 sigma upper limit for very low mass binary frequency is 18%. Our targets included 7 known, wide brown dwarf binary systems. No significant radial velocity variability was measured in our multi-epoch observations of these systems, even for those pairs for which our data spanned a significant ...

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

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

    Energy WattStation AC Level 2 Charging System Testing Results AVTA: GE Energy WattStation AC Level 2 Charging System Testing Results The Vehicle Technologies Office's Advanced...

  15. Biocompatible Silver-containing a-C:H and a-C coatings: A Comparative Study

    E-Print Network [OSTI]

    Endrino, Jose Luis; Allen, Matthew; Escobar Galindo, Ramon; Zhang, Hanshen; Anders, Andre; Albella, Jose Maria

    2007-01-01

    containing a-C:H and a-C coatings: A comparative Study Josefree amorphous carbon (a-C) coatings are known to beinto diamond-like carbon (DLC) coatings by plasma based ion

  16. Docket No. EERE-2011-BT-NOA-0067 and RIN Number 1904-AC52 Ex...

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

    1-BT-NOA-0067 and RIN Number 1904-AC52 Ex parte Communication Docket No. EERE-2011-BT-NOA-0067 and RIN Number 1904-AC52 Ex parte Communication This memorandum for the record...

  17. A Frequency Analysis of Light Transport

    E-Print Network [OSTI]

    Durand, Frédo

    #12;A Frequency Analysis of Light Transport F. Durand, MIT CSAIL N. Holzschuch, C. Soler, ARTIS lighting onlyDirect lighting only #12;Frequency aspects of light transport · Blurriness = frequency content ­ From equations of light transport #12;Unified framework: · Spatial frequency (e.g. shadows, textures

  18. Optical and Radio Variability of BL Lacertae

    E-Print Network [OSTI]

    Gaur, Haritma; Bachev, R; Strigachev, A; Semkov, E; Wiita, Paul J; Volvach, A E; Gu, Minfeng; Agarwal, A; Agudo, I; Aller, M F; Aller, H D; Kurtanidze, O M; Kurtanidze, S O; Lahteenmaki, A; Peneva, S; Nikolashvili, M G; Sigua, L A; Tornikoski, M; Volvach, L N

    2015-01-01

    We observed the prototype blazar, BL Lacertae, extensively in optical and radio bands during an active phase in the period 2010--2013 when the source showed several prominent outbursts. We searched for possible correlations and time lags between the optical and radio band flux variations using multifrequency data to learn about the mechanisms producing variability. During an active phase of BL Lacertae, we searched for possible correlations and time lags between multifrequency light curves of several optical and radio bands. We tried to estimate any possible variability timescales and inter-band lags in these bands. We performed optical observations in B, V, R and I bands from seven telescopes in Bulgaria, Georgia, Greece and India and obtained radio data at 36.8, 22.2, 14.5, 8 and 4.8 GHz frequencies from three telescopes in Ukraine, Finland and USA. Significant cross-correlations between optical and radio bands are found in our observations with a delay of cm-fluxes with respect to optical ones of ~250 days...

  19. WECC Variable Generation Planning Reference Book: Appendices

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

    2013-05-13

    The document titled “WECC Variable Generation Planning Reference Book”. This book is divided into two volumes; one is the main document (volume 1)and the other is appendices (volume 2). The main document is a collection of the best practices and the information regarding the application and impact of variables generation on power system planning. This volume (appendices) has additional information on the following topics: Probabilistic load flow problems. 2. Additional useful indices. 3. high-impact low-frequency (HILF) events. 4. Examples of wide-area nomograms. 5. Transmission line ratings, types of dynamic rating methods. 6. Relative costs per MW-km of different electric power transmission technologies. 7. Ultra-high voltage (UHV) transmission. 8.High voltage direct current (VSC-HVDC). 9. HVDC. 10. Rewiring of existing transmission lines. 11. High-temperature low sag (HTLS) conductors. 12. The direct method and energy functions for transient stability analysis in power systems. 13.Blackouts caused by voltage instability. 14. Algorithm for parameter continuation predictor-corrector methods. 15. Approximation techniques available for security regions. 16. Impacts of wind power on power system small signals stability. 17. FIDVR. 18. FACTS. 19. European planning standard and practices. 20. International experience in wind and solar energy sources. 21. Western Renewable Energy Zones (WREZ). 22. various energy storage technologies. 23. demand response. 24. BA consolidation and cooperation options. 25. generator power management requirements and 26. European planning guidelines.

  20. AC&N Incident Reporting The Colorado School of Mines takes all complaints about inappropriate traffic

    E-Print Network [OSTI]

    not help with email that originated outside the CSM network. Please see the AC&N Spam Management web page

  1. 9 17 25 3 http://www.adm.u-tokyo.ac.jp/gakunai/office/anzenei

    E-Print Network [OSTI]

    Goda, Keisuke

    ://www.adm.u-tokyo.ac.jp/gakunai/office/anzenei sei/org/taisei.html [ HP] 2. UTCRIS 18 3 UTCRIS #12;https-1 HP http://www.esc.u-tokyo.ac.jp/haisui/index.html [HP] 5. 3-3 2 3 3 2 2 1,1- HP http://www.adm.u-tokyo.ac.jp/office/anzeneisei/admin/tokutei_kagaku.html [ HP] 6. 6 HP http://www.esc.u-tokyo.ac.jp/seihai/seihai.html

  2. Boys and Girls, Be Ambitious! http://www.math.sci.hokudai.ac.jp/message/message-graduates/

    E-Print Network [OSTI]

    Nakamura, Iku

    ://www.math.sci.hokudai.ac.jp/ #12;AIKAWA, Hiroaki WebPage http://www.math.sci.hokudai.ac.jp/ aik/index-j.html Fatou Martin Harnack AKITA, Toshiyuki WebPage http://www.math.sci.hokudai.ac.jp/ akita/ Eilenberg-MacLane Coxeter #12;ASAKURA, Masanori ARAI, Asao ABE, Noriyuki WebPage http://www.math.sci.hokudai.ac.jp/ abenori/ #12;ISHIKAWA, Goo Web

  3. A simple hidden variable experiment

    E-Print Network [OSTI]

    Arnold Neumaier

    2007-06-22

    An experiment is described which proves, using single photons only, that the standard hidden variables assumptions (commonly used to derive Bell inequalities) are inconsistent with quantum mechanics. The analysis is very simple and transparent. In particular, it demonstrates that a classical wave model for quantum mechanics is not ruled out by experiments demonstrating the violation of the traditional hidden variable assumptions.

  4. Wind/PV Generation for Frequency Regulation and Oscillation Damping in the Eastern Interconnection

    SciTech Connect (OSTI)

    Liu, Yong; Gracia, Jose R; Hadley, Stanton W; Liu, Yilu

    2013-12-01

    This report presents the control of renewable energy sources, including the variable-speed wind generators and solar photovoltaic (PV) generators, for frequency regulation and inter-area oscillation damping in the U.S. Eastern Interconnection (EI). In this report, based on the user-defined wind/PV generator electrical control model and the 16,000-bus Eastern Interconnection dynamic model, the additional controllers for frequency regulation and inter-area oscillation damping are developed and incorporated and the potential contributions of renewable energy sources to the EI system frequency regulation and inter-area oscillation damping are evaluated.

  5. Aalborg Universitet Active Power Regulation based on Droop for AC Microgrid

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Active Power Regulation based on Droop for AC Microgrid Li, Chendan; Coelho., Quintero, J. C. V., & Guerrero, J. M. (2015). Active Power Regulation based on Droop for AC Microgrid.aau.dk on: november 29, 2015 #12;Active Power Regulation based on Droop for AC Microgrid Chendan Li, Student

  6. Aalborg Universitet Stability Analysis for Isolated AC Microgrids Based on PV-Active Generators

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Aalborg Universitet Stability Analysis for Isolated AC Microgrids Based on PV-Active Generators for Isolated AC Microgrids Based on PV-Active Generators. In Proceedings of the 2015 IEEE Energy Conversion.aau.dk on: november 29, 2015 #12;Stability Analysis for Isolated AC Microgrids Based on PV-Active Generators

  7. STFC Feb. 2015SCAPA dino@phys.strath.ac.uk Scottish Universities Physics Alliance

    E-Print Network [OSTI]

    STFC Feb. 2015SCAPA dino@phys.strath.ac.uk Scottish Universities Physics Alliance MEDICAL dino@phys.strath.ac.uk Scottish Universities Physics Alliance Laser beam driven plasma accelerators X dose maps #12;STFC Feb. 2015SCAPA dino@phys.strath.ac.uk Scottish Universities Physics Alliance

  8. http://www.up.ac.za/academic/fabi/tpcp/pamphlets/phytophthora.htm PHYTOPHTHORA ROOT AND COLLAR

    E-Print Network [OSTI]

    http://www.up.ac.za/academic/fabi/tpcp/pamphlets/phytophthora.htm PHYTOPHTHORA ROOT AND COLLAR ROT cold weather the fungus survives as oospores, chlamydospores http://www.up.ac.za/academic/fabi/tpcp/pamphlets/phytophthora.htm (1 of 4) [2002/02/26 01:54:52] #12;http://www.up.ac.za/academic/fabi/tpcp/pamphlets

  9. http://www.up.ac.za/academic/fabi/tpcp/pamphlets/dothistroma.htm DOTHISTROMA NEEDLE BLIGHT

    E-Print Network [OSTI]

    http://www.up.ac.za/academic/fabi/tpcp/pamphlets/dothistroma.htm DOTHISTROMA NEEDLE BLIGHT is necessary and routinely applied. At present, the disease is not http://www.up.ac.za/academic/fabi/tpcp/pamphlets/dothistroma.htm (1 of 2) [2002/02/26 01:53:43] #12;http://www.up.ac.za/academic/fabi/tpcp/pamphlets

  10. http://www.up.ac.za/academic/fabi/tpcp/pamphlets/mycosphaerella.htm MYCOSPHAERELLA

    E-Print Network [OSTI]

    http://www.up.ac.za/academic/fabi/tpcp/pamphlets/mycosphaerella.htm MYCOSPHAERELLA LEAF DISEASES leaf blotch develop adult leaves rapidly and are not seriously http://www.up.ac.za/academic/fabi/tpcp/pamphlets/mycosphaerella.htm (1 of 3) [2002/02/26 01:54:11] #12;http://www.up.ac.za/academic/fabi/tpcp/pamphlets

  11. http://www.up.ac.za/academic/fabi/tpcp/pamphlets/coniothyrium.htm CONIOTHYRIUM CANKER OF

    E-Print Network [OSTI]

    http://www.up.ac.za/academic/fabi/tpcp/pamphlets/coniothyrium.htm CONIOTHYRIUM CANKER OF EUCALYPTUS risk areas. Coniothyrium canker and spores of the fungus. http://www.up.ac.za/academic/fabi/tpcp/pamphlets/coniothyrium.htm (1 of 2) [2002/02/26 01:49:46] #12;http://www.up.ac.za/academic/fabi/tpcp/pamphlets

  12. Low-frequency, self-sustained oscillations in inductively coupled plasmas used for optical pumping

    SciTech Connect (OSTI)

    Coffer, J.; Encalada, N.; Huang, M.; Camparo, J. [Physical Sciences Laboratories, The Aerospace Corporation 2310, E. El Segundo Blvd., El Segundo, California 90245 (United States)

    2014-10-28

    We have investigated very low frequency, on the order of one hertz, self-pulsing in alkali-metal inductively-coupled plasmas (i.e., rf-discharge lamps). This self-pulsing has the potential to significantly vary signal-to-noise ratios and (via the ac-Stark shift) resonant frequencies in optically pumped atomic clocks and magnetometers (e.g., the atomic clocks now flying on GPS and Galileo global navigation system satellites). The phenomenon arises from a nonlinear interaction between the atomic physics of radiation trapping and the plasma's electrical nature. To explain the effect, we have developed an evaporation/condensation theory (EC theory) of the self-pulsing phenomenon.

  13. Comparative Study of Magnetic Properties of Nanoparticles by High-Frequency Heat Dissipation and Conventional Magnetometry

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

    Malik, V.; Goodwill, J.; Mallapragada, S.; Prozorov, T.; Prozorov, R.

    2014-11-13

    The rate of heating of a water-based colloid of uniformly sized 15 nm magnetic nanoparticles by high-amplitude and high-frequency ac magnetic field induced by the resonating LC circuit (nanoTherics Magnetherm) was measured. The results are analyzed in terms of specific energy absorption rate (SAR). Fitting field amplitude and frequency dependences of SAR to the linear response theory, magnetic moment per particles was extracted. The value of magnetic moment was independently evaluated from dc magnetization measurements (Quantum Design MPMS) of a frozen colloid by fitting field-dependent magnetization to Langevin function. The two methods produced similar results, which are compared to themore »theoretical expectation for this particle size. Additionally, analysis of SAR curves yielded effective relaxation time.« less

  14. Comparative Study of Magnetic Properties of Nanoparticles by High-Frequency Heat Dissipation and Conventional Magnetometry

    SciTech Connect (OSTI)

    Malik, V.; Goodwill, J.; Mallapragada, S.; Prozorov, T.; Prozorov, R.

    2014-11-13

    The rate of heating of a water-based colloid of uniformly sized 15 nm magnetic nanoparticles by high-amplitude and high-frequency ac magnetic field induced by the resonating LC circuit (nanoTherics Magnetherm) was measured. The results are analyzed in terms of specific energy absorption rate (SAR). Fitting field amplitude and frequency dependences of SAR to the linear response theory, magnetic moment per particles was extracted. The value of magnetic moment was independently evaluated from dc magnetization measurements (Quantum Design MPMS) of a frozen colloid by fitting field-dependent magnetization to Langevin function. The two methods produced similar results, which are compared to the theoretical expectation for this particle size. Additionally, analysis of SAR curves yielded effective relaxation time.

  15. A simple model for 1/f spectra in heart rate variability James P. Gleesona and Aneta Stefanovskab

    E-Print Network [OSTI]

    Gleeson, James P.

    , Lancaster, LA1 4YB, UK. ABSTRACT Heart rate variability (HRV) measures cycle-to-cycle correlations of a sum of uncoupled sinusoidal oscillators with slightly different frequencies, has a HRV spectrum with a 1/f scaling over a range of frequencies. This implies that the appearance of 1/f HRV spectra

  16. 882 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 47, NO. 6, JUNE 1999 State-Variable-Based Transient Analysis

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    , circuit transient analysis, convolution, nonlinear circuits, solitons, state variables. I. INTRODUCTION TRANSIENT analysis of distributed microwave circuits is complicated by the inability of frequency, the linear part of a microwave circuit is described in the frequency domain by network parameters, especially

  17. Single photon continuous variable quantum key distribution based on energy-time uncertainty relation

    E-Print Network [OSTI]

    Bing Qi

    2006-02-20

    In previous quantum key distribution (QKD) protocols, information is encoded on either the discrete-variable of single-photon signal or continuous-variables of multi-photon signal. Here, we propose a new QKD protocol by encoding information on continuous-variables of a single photon. In this protocol, Alice randomly encodes her information on either the central frequency of a narrow-band single photon pulse or the time-delay of a broadband single photon pulse, while Bob randomly chooses to do either frequency measurement or time measurement. The security of this protocol rests on the energy-time uncertainty relation, which prevents Eve from simultaneously determining both frequency and time information with arbitrarily high resolution. In practice, this scheme may be more robust against various channel noises, such as polarization and phase fluctuations.

  18. Recent developments in thermoacoustically-driven low-frequency projectors

    SciTech Connect (OSTI)

    Ward, W.C.; Merrigan, M.A.

    1992-01-01

    Thermoacoustic engines are a recent class of devices that can efficiently convert heat to acoustic energy without moving parts or intervening mechanisms. These engines have a natural potential for powering low-frequency sonar projectors with high reliability and efficiencies that cannot be matched by conventional technologies. A recent design study has produced thermoacoustic projector configurations that can execute standard projector performance requirements such as FM sweep and velocity magnitude and phase control in array environments for a wide range of positive and negative radiation resistances. The thermoacoustic driver is a vertically oriented, helium-filled resonator that contains a movable tuning element to vary the resonator frequency. It is coupled to a variable length water column that is tunable by a similar means to adjust the effective source impedance of the device. Modeling results indicate a sweep range of at least an octave for a single device, and maximum overall (heat-to-acoustic) conversion efficiencies of 25% at 50 Hz. Efficiency increases slightly at lower frequencies, and the lowest operational frequency is limited only by the size of the projector. Output power increases linearly with mean pressure, and at depths of 200 m or more, power densities in excess of 500 kW/m{sup 2} are achievable. Control aspects have been investigated, including rapid startup and shutdown that can be performed by manipulating the water tuning column. Future trends and development prospects are discussed. 4 refs.

  19. Recent developments in thermoacoustically-driven low-frequency projectors

    SciTech Connect (OSTI)

    Ward, W.C.; Merrigan, M.A.

    1992-05-01

    Thermoacoustic engines are a recent class of devices that can efficiently convert heat to acoustic energy without moving parts or intervening mechanisms. These engines have a natural potential for powering low-frequency sonar projectors with high reliability and efficiencies that cannot be matched by conventional technologies. A recent design study has produced thermoacoustic projector configurations that can execute standard projector performance requirements such as FM sweep and velocity magnitude and phase control in array environments for a wide range of positive and negative radiation resistances. The thermoacoustic driver is a vertically oriented, helium-filled resonator that contains a movable tuning element to vary the resonator frequency. It is coupled to a variable length water column that is tunable by a similar means to adjust the effective source impedance of the device. Modeling results indicate a sweep range of at least an octave for a single device, and maximum overall (heat-to-acoustic) conversion efficiencies of 25% at 50 Hz. Efficiency increases slightly at lower frequencies, and the lowest operational frequency is limited only by the size of the projector. Output power increases linearly with mean pressure, and at depths of 200 m or more, power densities in excess of 500 kW/m{sup 2} are achievable. Control aspects have been investigated, including rapid startup and shutdown that can be performed by manipulating the water tuning column. Future trends and development prospects are discussed. 4 refs.

  20. Vortex precession frequency and its amplitude-dependent shift in cylindrical nanomagnets

    SciTech Connect (OSTI)

    Metlov, Konstantin L.

    2013-12-14

    Frequency of free magnetic vortex precession in circular soft ferromagnetic nano-cylinders (magnetic dots) of various sizes is an important parameter, used in design of spintronic devices (such as spin-torque microwave nano-oscillators) and characterization of magnetic nanostructures. Here, using a recently developed collective-variable approach to non-linear dynamics of magnetic textures in planar nano-magnets, this frequency and its amplitude-dependent shift are computed analytically and plotted for the full range of cylinder geometries. The frequency shift is positive in large planar dots, but becomes negative in smaller and more elongated ones. At certain dot dimensions, a zero frequency shift is realized, which can be important for enhancing frequency stability of magnetic nano-oscillators.

  1. www.weizmann.ac.il/library Introduction 3

    E-Print Network [OSTI]

    to the Library's printed and digital collections, including books, journals, theses, serials, and online lectures Weizmann Institute of Science Libraries 5 Digital Access · Arranging access to newly purchased electronic#12;www.weizmann.ac.il/library 2 Contents Introduction 3 The Library's Website 3 The Library

  2. 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's consultation on Electricity Market Reform proposed that low- carbon electricity generators should be offered entrants and new sources of finance to be tapped for the massive low-carbon generation investment needed

  3. 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 slow pyrolysis process. Chicken litter6 (CL) was pyrolysed with a highest temperature of treatment (HTT)). A summer sweet corn, winter16 pulse rotation was established at the site.17 Soil samples (ca. 1 kg) were

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

    E-Print Network [OSTI]

    Aickelin, Uwe

    This paper summarises and reviews scholarly and political comment that draws parallels between the current: the nature of the political discourse; the relationship between an ethics-driven societal shift and economic Change, Slavery, Political Rhetoric JEL Classification B15 Contact wjn21@cam.ac.uk Publication August

  5. No. 426 June 2013 newsletter.lms.ac.uk

    E-Print Network [OSTI]

    Abrahams, I. David

    No. 426 June 2013 1 NEWSLETTER ONLINE: newsletter.lms.ac.uk NEWSLETTER LONDON MATHEMATICAL SOCIETY Society Meetings and Events 2013 10-14 June LMS Invited Lectures, Edinburgh page 16 Tuesday 11 June Midlands Regional Meeting, Leicester page 11 Tuesday 25 June LMS Popular Lectures, London page 17 Friday 5

  6. No. 427 July 2013 newsletter.lms.ac.uk

    E-Print Network [OSTI]

    Abrahams, I. David

    1 No. 427 July 2013 NEWSLETTER ONLINE: newsletter.lms.ac.uk NEWSLETTER LONDON MATHEMATICAL SOCIETY September LMS Popular Lectures, Birmingham page 4 Friday 15 November LMS AGM, London Monday 16 December SW, France and 2010 LMS Whitehead Prize winner has demonstrated the solution to a 271-year-old problem

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

    E-Print Network [OSTI]

    Aickelin, Uwe

    of 107 Strategic Eurasian Natural Gas Model for Energy Security and Policy Analysis1 Chi-Kong Chyongwww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Strategic Eurasian Natural Gas Model for Energy-Kong Chyong and Benjamin F. Hobbs The mathematical formulation of a large-scale equilibrium natural gas

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

    E-Print Network [OSTI]

    Aickelin, Uwe

    . Although large-scale natural gas models have been developed and used for energy security and policywww.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Strategic Eurasian Natural Gas Model-scale equilibrium natural gas simulation model that covers gas markets of the EU and the Former Soviet Union

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

    E-Print Network [OSTI]

    Aickelin, Uwe

    in concern about the security of natural gas supply to Europe, particularly supplies from Russia. A numberwww.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Gas Supply Security in the Baltic, determining its level of security is a virtually impossible. The specific gas supply set up, the structure

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

    E-Print Network [OSTI]

    Aickelin, Uwe

    in place designed to mitigate the effects of a disruption. Keywords Natural Gas, security of supply, Baltic not entirely, by the rise in concern about the security of natural gas supply to Europe, particularly supplieswww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Gas Supply Security in the Baltic States

  11. Physics and www.manchester.ac.uk/physicsUNDERGRADUATEBROCHURE2014

    E-Print Network [OSTI]

    Physics and Astronomy www.manchester.ac.uk/physicsUNDERGRADUATEBROCHURE2014 #12;One of Britain's largest and most respected schools of Physics and Astronomy, with top ratings for teaching and research, and two Nobel Prize winners in 2010 Recent £70 million extension and refurbishment of the Physics

  12. Physics and www.manchester.ac.uk/physicsUNDERGRADUATEBROCHURE2015

    E-Print Network [OSTI]

    Physics and Astronomy www.manchester.ac.uk/physicsUNDERGRADUATEBROCHURE2015 #12;One of Britain's largest and most respected schools of Physics and Astronomy, with top ratings for teaching and research, and two Nobel Prize winners in 2010 Recent £70 million extension and refurbishment of the Physics

  13. Thermal Unit Commitment Including Optimal AC Power Flow Constraints

    E-Print Network [OSTI]

    Thermal Unit Commitment Including Optimal AC Power Flow Constraints Carlos Murillo{Sanchez Robert J algorithm for unit commitment that employs a Lagrange relaxation technique with a new augmentation. This framework allows the possibility of committing units that are required for the VArs that they can produce

  14. ENGINEERING & THE BUILT ENVIRONMENT www.wits.ac.za/engineering

    E-Print Network [OSTI]

    Wagner, Stephan

    29 ENGINEERING & THE BUILT ENVIRONMENT www.wits.ac.za/engineering #12;30 Wits fact The Wits Mining, management, sociology, migration, eco- nomics, engineering, healthcare, materials science, geology, energy of Mechanical, Industrial and Aeronautical Engineering was awarded an Honorary Fellowship of the Royal

  15. SCHOOL OF ENGINEERING www.abdn.ac.uk/engineering

    E-Print Network [OSTI]

    Neri, Peter

    SCHOOL 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 MSc Oil & Gas Structural Engineering Our Programmes #12;Why Aberdeen Founded in 1495, the University

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

    E-Print Network [OSTI]

    Aickelin, Uwe

    wind power, long-term contracts, balancing costs JEL Classification Q42, L14, L94 Contact dmgn. The estimated extra trading and balancing costs of a CfD for on-shore wind might be £70 million/yr by 2020www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Contracting for wind generation EPRG Working

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

    E-Print Network [OSTI]

    de Gispert, Adrià

    as uncertainties are resolved reduces significantly its expected Levelised Cost Of generating Electricity (LCOE deterministic economic model to identify its LCOE without considering uncertainty. In the second step #12;www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY we identified sources of uncertainty in the design that would affect its LCOE

  18. AcAdemic (100133) 100 Edmon Low Library

    E-Print Network [OSTI]

    AcAdemic (100­133) 100 Edmon Low Library 101 Henry Bellmon Research Center 102 Classroom Building ­ Residential Life Office 216 University Health Services 217 The Little Bakery 218 Public Information 219 406 Intramural fields 407 Cowgirl Soccer Field 408 Theta Pond 409 Library Lawn 410 Droke Track & Field

  19. Assembly of Multi-Stranded Nanofiber Threads through AC Electrospinning

    E-Print Network [OSTI]

    Chang, Hsueh-Chia

    Assembly of Multi-Stranded Nanofiber Threads through AC Electrospinning By Siddharth Maheshwari and Hsueh-Chia Chang* Electrospinning refers to the formation of micrometer and sub-micrometer fibers under, self-assembly of individual molecules, etc., electrospinning provides a robust method to form long

  20. SCHOOL OF NATURAL AND www.abdn.ac.uk/ncs

    E-Print Network [OSTI]

    Neri, Peter

    SCHOOL OF NATURAL AND www.abdn.ac.uk/ncs COMPUTING SCIENCES POSTGRADUATE GUIDE #12;MSc Information Management MSc Environmental Analytical Chemistry MSc Oil & Gas Chemistry MSc Mathematics Our Programmes #12 reputation for teaching quality and research and has had, over the years, five Nobel Prize winners

  1. www.birmingham.ac.uk Postgraduate Offer Guide

    E-Print Network [OSTI]

    Miall, Chris

    www.birmingham.ac.uk Postgraduate Offer Guide 2014 ­ 2015 #12;2 Postgraduate offer guide Welcome to the University of Birmingham Your offer from the University Congratulations! We are delighted to inform you that you have been offered a place to study at the University of Birmingham. We do hope that you decide

  2. 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

  3. 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'ÊTRE IS TO SERVE

  4. http://stir.ac.uk/4l Why study Management?

    E-Print Network [OSTI]

    Little, Tony

    http://stir.ac.uk/4l BSc(Hons) Management #12;Why study Management? Management essentially combines the flow of patients through hospital departments. Other modules include: Business Strategy, Project Management Case Studies and Energy Supply Case Study. Did you know? Excellent Management practice is required

  5. Beaming into matter and life www.cockcroft.ac.uk

    E-Print Network [OSTI]

    Crowther, Paul

    Beaming into matter and life www.cockcroft.ac.uk COCKCROFT STRATEGY MAP 2014-2020 Vision Continue and train the next generation of scientists and engineers, address societal challenges in energy · Globally Unique Skills Base · Societal Impact: Energy, Environment, Health, Security Strategic Enablers

  6. contents | print | close www.glasgow.ac.uk

    E-Print Network [OSTI]

    Guo, Zaoyang

    1 contents | print | close www.glasgow.ac.uk Gilmorehill Campus Development Framework June 2014 : Topic 4 107 Approach to Historic Assets: Sub Topics 108 · A Campus-wide Conservation Strategy 108 · Introduction 134 · Relevant Consultation Themes : Topic 7 135 Uses & Adaptability : Sub Topics 136 · Energy

  7. contents | print | close www.glasgow.ac.uk

    E-Print Network [OSTI]

    Guo, Zaoyang

    1 contents | print | close www.glasgow.ac.uk Gilmorehill Campus Development Framework FINAL : Topic 4 107 Approach to Historic Assets: Sub Topics 108 · A Campus-wide Conservation Strategy 108 · Introduction 134 · Relevant Consultation Themes : Topic 7 135 Uses & Adaptability : Sub Topics 136 · Energy

  8. RELIABLE CELLULAR AUTOMATA WITH SELF-ORGANIZATION PETER G ACS

    E-Print Network [OSTI]

    Gacs, Peter

    RELIABLE CELLULAR AUTOMATA WITH SELF-ORGANIZATION PETER G ´ACS ABSTRACT. In a probabilistic cellular automaton in which all local transitions have positive probability, the problem of keeping a bit-tolerant cellular automaton. This technique does not help much to solve the following problems: remembering a bit

  9. 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

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

    E-Print Network [OSTI]

    Aickelin, Uwe

    . Pollitt Economic drivers, technologies and demand side management are keys in understanding the long-economic context of energy demand, and the tension between technically possible energy savings one one sidewww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract The Economics of Energy (and Electricity) Demand

  11. Chemistry (ACS) College of Science CHEM-BSCHM

    E-Print Network [OSTI]

    Kihara, Daisuke

    (2)CHM26600 Organic Chemistry Lab (4)CHM32100 Analytical Chemistry I (4)CHM24100 Intro to Inorganic Chemistry (3)CHM37400 Physical Chemistry (2)CHM37600 Physical Chemistry Lab (4)CHM 42400 AnalyticalChemistry (ACS) College of Science CHEM-BSCHM CHMA 120 Credits 2.0 GPA in CHM courses and 2.0 GPA

  12. www.abdn.ac.uk/study Global Health

    E-Print Network [OSTI]

    Neri, Peter

    www.abdn.ac.uk/study Global Health & Management Master of Science/Postgraduate Diploma MSc/PgDip #12;The programme begins with cross-disciplinary Public Health Research training (Applied Statistics, Epidemiology, Qualitative Methods, Health Services Research and Systematic Reviewing) followed by courses

  13. Autonomic effects of refractory epilepsy on heart rate variability in children: influence of intermittent vagus nerve stimulation

    E-Print Network [OSTI]

    HRV Heart rate variability LFnu Low-frequency normalized units SWS Slow-wave sleep VNS Vagus nerve to be responsible for the therapeutic effect of VNS. Heart rate variability (HRV) is defined as the fluctuation there is still a relatively large influence of the sympathetic branch on HRV. In typically developing individuals

  14. Variable rate CELP speech coding using widely variable parameter updates 

    E-Print Network [OSTI]

    Moodie, Myron L.

    1995-01-01

    Code-excited, linear prediction (CELP) has become an accepted method for low bit rate, high quality coding of digital speech. The success of fixed rate CELP schemes has led to increased interest in variable rate techniques ...

  15. CONTRIBUTED Variability Effects in Graphene

    E-Print Network [OSTI]

    , which form a critical issue in examining the feasibility of graphene devices for large-scale production has shown its potential in wafer-scale radio- frequency analog circuits [16]­[23], broadband photo

  16. Cost vs. performance ... Gwyn Griffiths email: gxg@noc.soton.ac.uk http://www.noc.soton.ac.uk/OED/gxg/

    E-Print Network [OSTI]

    Griffiths, Gwyn

    ) Specific energy (Wh.kg-1 ) Cell cost per kWh (£) Cost per kWh inc. assembly & disposal. (£) Mn Alkaline 0@noc.soton.ac.uk http://www.noc.soton.ac.uk/OED/gxg/ Chemistry Cost per cell in quantity (£) Energy per cell (Wh://www.noc.soton.ac.uk/OED/gxg/ Cost & performance of Li-Po secondary batteries Component Capital cost Amortised cost per kWh Cost per

  17. Dec 17, 2004 www.dcs.bbk.ac.uk/~gmagoulas/teaching.html 1 Dec 17, 2004 www.dcs.bbk.ac.uk/~gmagoulas/teaching.html 2

    E-Print Network [OSTI]

    Magoulas, George D.

    Infrastructure l Server architecture l Software for web servers l E-commerce web sites Dec 17, 2004 www.dcs.bbk.ac.uk/~gmagoulas/teaching.html significant implications for Web (and e- commerce) application development. Dec 17, 2004 www.dcs.bbk.ac.uk/~gmagoulas/teaching.html 9 E-Commerce Web Sites- An open system: the Web Dec 17, 2004 www.dcs.bbk.ac.uk/~gmagoulas/teaching.html

  18. Optical Variability of Infrared Power Law-Selected Galaxies & X-ray Sources in the GOODS-South Field

    E-Print Network [OSTI]

    Alison Klesman; Vicki Sarajedini

    2007-05-07

    We investigate the use of optical variability to identify and study Active Galactic Nuclei (AGN) in the GOODS-South field. A sample of 22 mid-infrared power law sources and 102 X-ray sources with optical counterparts in the HST ACS images were selected. Each object is classified with a variability significance value related to the standard deviation of its magnitude in five epochs separated by 45-day intervals. The variability significance is compared to the optical, mid-IR, and X-ray properties of the sources. We find that 26% of all AGN candidates (either X-ray- or mid-IR-selected) are optical variables. The fraction of optical variables increases to 51% when considering sources with soft X-ray band ratios. For the mid-IR AGN candidates which have multiwavelength SEDs, we find optical variability for 64% of those classified with SEDs like Broad Line AGNs. While mostly unobscured AGN appear to have the most significant optical variability, some of the more obscured AGNs are also observed as variables. In particular, we find two mid-IR power law-selected AGN candidates without X-ray emission that display optical variability, confirming their AGN nature.

  19. Low-frequency variability of currents in the deepwater eastern Gulf of Mexico 

    E-Print Network [OSTI]

    Cole, Kelly Lynne

    2009-05-15

    in the Yucatan Channel.......................... 9 1.6 The efects of topography on Gulf of Mexico circulation.......... 11 1.7 Partitioning of kinetic energy amongst dynamic modes........... 12 1.8 Scientific questions and hypotheses...................... 70 3.5.7 Dynamic mode kinetic energy and modal coupling......... 74 3.5.8 Modal decomposition of EGOM data versus historical data.. 78 4. DISCUSION AND CONCLUSIONS.............................. 81 REFERENCES...

  20. The temperature-jump problem for a variable collision frequency model L. B. Barichello

    E-Print Network [OSTI]

    Siewert, Charles E.

    -900 Porto Alegre, RS, Brazil M. Camargoa) Programa de Po´s-Graduac¸a~o em Engenharia Meca^nica, Universidade

  1. Understanding the low-frequency variability in hydroclimatic attributes over the southeastern US

    E-Print Network [OSTI]

    Arumugam, Sankar

    that reliable projections of climatic conditions such as El-Nino Southern Oscillations (ENSO) over the near

  2. PV Arc Fault Detector Challenges Due to Module Frequency Response Variability

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access| Department ofStephen P riceawardsPROCESSING ANDas

  3. Multi-frequency imaging in VLBI

    E-Print Network [OSTI]

    S. Likhachev

    2004-12-17

    The new technique, multi-frequency imaging (MFI) is developed. In VLBI, Multi-Frequency Imaging (MFI) consists of multi-frequency synthesis (MFS) and multi-frequency analysis (MFA) of the VLBI data obtained from observations on various frequencies. A set of linear deconvolution MFI algorithms is described. The algorithms make it possible to obtain high quality images interpolated on any given frequency inside any given bandwidth, and to derive reliable estimates of spectral indexes for radio sources with continuum spectrum. Thus MFI approach makes it is possible not only to improve the quality and fidelity of the images and also essentially to derive the morphology of the observed radio sources.

  4. Quantitative Depth Profiling of Biporous Nickel Electrodes by Frequency-Domain Laser-Induced

    E-Print Network [OSTI]

    Mandelis, Andreas

    for the long-term stability and high efficiency of electrochemical energy conversion in fuel cells manufactured for use in electrochemical energy conversion de- vices, such as fuel cells. Index Headings: Laser-induced photoacoustic spectroscopy; Variable electrode porosities; Frequency response; Quantitative analysis; Fuel cells

  5. Photoacoustic frequency-domain depth profilometry of surface-layer inhomogeneities: Application to laser processed steels

    E-Print Network [OSTI]

    Mandelis, Andreas

    (laser or electron beam), modulated at a certain frequency is focused onto the sample surface and Optodmronic Diagnostics Laboratory, Department of Mechanical Engineering, Uniuerxity of Toronto, Toronto with a variable depth range, compared to conventional tech- niques. In this family of methods a beam of energy

  6. A Comparative Study of Time-Frequency Representations for Fault Detection in Wind Turbine

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A Comparative Study of Time-Frequency Representations for Fault Detection in Wind Turbine El of wind energy, minimization and prediction of maintenance operations in wind turbine is of key importance. In variable speed turbine generator, advanced signal processing tools are required to detect and diagnose

  7. High frequency acoustic transmission loss of perforated plates at normal incidence

    E-Print Network [OSTI]

    Papamoschou, Dimitri

    High frequency acoustic transmission loss of perforated plates at normal incidence Vincent Phonga conducted on the transmission loss of perforated plates at normal incidence. The investigation includes microphone measurements of transmission loss for 11 perforated plates with variable thickness, hole size

  8. A Near State PWM Method With Reduced Switching Frequency And Reduced Common Mode Voltage

    E-Print Network [OSTI]

    Hava, Ahmet

    operation in AC-DC power converter applications, and supply high quality power in uninterruptible power supply AC-DC-AC power converter units. Pulse Width Modulation (PWM) is the standard approach to operate

  9. Anyonic statistics with continuous variables

    E-Print Network [OSTI]

    Jing Zhang; Changde Xie; Kunchi Peng; Peter van Loock

    2008-10-30

    We describe a continuous-variable scheme for simulating the Kitaev lattice model and for detecting statistics of abelian anyons. The corresponding quantum optical implementation is solely based upon Gaussian resource states and Gaussian operations, hence allowing for a highly efficient creation, manipulation, and detection of anyons. This approach extends our understanding of the control and application of anyons and it leads to the possibility for experimental proof-of-principle demonstrations of anyonic statistics using continuous-variable systems.

  10. Health Sciences and Nursing Health Sociology http://www.hlthsoc.m.u-tokyo.ac.jp/indexj.htm

    E-Print Network [OSTI]

    Miyashita, Yasushi

    .m.u-tokyo.ac.jp/dept/famn/indexj.htm · · · · · · #12;47 Community Health Nursing http://park.itc.u-tokyo.ac.jp/chn/ · · · · · · · · · · · Adult NursingHealth Sciences and Nursing Health Sociology http://www.hlthsoc.m.u-tokyo.ac.jp/indexj.htm · · · · · · Mental Health / Psychiatric Nursing http://plaza.umin.ac.jp/~heart/ · · · · · · · · · · · · · #12

  11. Computational Complexity of Itemset Frequency Satisfiability

    E-Print Network [OSTI]

    Antwerpen, Universiteit

    .calders@ua.ac.be Tel: +32 3 265 38 61 Fax: +32 3 265 37 77 University of Antwerp, Belgium Middelheimlaan 1, BE-2020 Antwerpen ABSTRACT Computing frequent itemsets is one of the most prominent problems in data mining. We becomes PP-hard. We describe applica- tions of FREQSAT in frequent itemset mining algorithms and privacy

  12. Frequency selective surfaces for Terahertz applications 

    E-Print Network [OSTI]

    Sanz Fernandez, Juan Jose; Fernandez, Juan Jose Sanz

    2012-11-29

    This thesis presents both theoretical and experimental investigations of the performance and capabilities of frequency selective surfaces (FSS) applied at THz frequencies. The aim is to explore and extend the use of FSS, ...

  13. REGULAR ARTICLE Warming and increased precipitation frequency

    E-Print Network [OSTI]

    Neher, Deborah A.

    REGULAR ARTICLE Warming and increased precipitation frequency on the Colorado Plateau: implications in temperature and precipitation are expected to influence ecosystem processes worldwide. Despite their globally how increased temperature and frequency of summertime precipitation affect the contributions of crust

  14. METHODS OF RADIO-FREQUENCY CURRENT DRIVE

    E-Print Network [OSTI]

    -670 Radio-frequency waves can penetrate thermonuclear plasmas, depositing momentum and energy with great. INTRODUCTION Using radio-frequency (rf) waves to drive the toroidal current in tokamak reactors is attractiveMETHODS OF RADIO-FREQUENCY CURRENT DRIVE N. J. FISCH* Princeton Plasma Physics Laboratory

  15. Introduction Final Cooling Channel -High Frequency RF

    E-Print Network [OSTI]

    McDonald, Kirk

    Outline Introduction Final Cooling Channel - High Frequency RF Muon Collider Final Cooling Hisham Sayed February 27, 2014 1 / 10 #12;Outline Introduction Final Cooling Channel - High Frequency RF Table of Contents 1 Introduction 2 Final Cooling Channel - High Frequency RF 2 / 10 #12;Outline Introduction Final

  16. Analysis of core damage frequency from internal events: Peach Bottom, Unit 2

    SciTech Connect (OSTI)

    Kolaczkowski, A.M.; Lambright, J.A.; Ferrell, W.L.; Cathey, N.G.; Najafi, B.; Harper, F.T.

    1986-10-01

    This document contains the internal event initiated accident sequence analyses for Peach Bottom, Unit 2; one of the reference plants being examined as part of the NUREG-1150 effort by the Nuclear Regulatory Commission. NUREG-1150 will document the risk of a selected group of nuclear power plants. As part of that work, this report contains the overall core damage frequency estimate for Peach Bottom, Unit 2, and the accompanying plant damage state frequencies. Sensitivity and uncertainty analyses provided additional insights regarding the dominant contributors to the Peach Bottom core damage frequency estimate. The mean core damage frequency at Peach Bottom was calculated to be 8.2E-6. Station blackout type accidents (loss of all ac power) were found to dominate the overall results. Anticipated Transient Without Scram accidents were also found to be non-negligible contributors. The numerical results are largely driven by common mode failure probability estimates and to some extent, human error. Because of significant data and analysis uncertainties in these two areas (important, for instance, to the most dominant scenario in this study), it is recommended that the results of the uncertainty and sensitivity analyses be considered before any actions are taken based on this analysis.

  17. On-Chip AC self-test controller

    DOE Patents [OSTI]

    Flanagan, John D. (Rhinebeck, NY); Herring, Jay R. (Poughkeepsie, NY); Lo, Tin-Chee (Fishkill, NY)

    2009-09-29

    A system for performing AC self-test on an integrated circuit that includes a system clock for normal operation is provided. The system includes the system clock, self-test circuitry, a first and second test register to capture and launch test data in response to a sequence of data pulses, and a logic circuit to be tested. The self-test circuitry includes an AC self-test controller and a clock splitter. The clock splitter generates the sequence of data pulses including a long data capture pulse followed by an at speed data launch pulse and an at speed data capture pulse followed by a long data launch pulse. The at speed data launch pulse and the at speed data capture pulse are generated for a common cycle of the system clock.

  18. Characterization of flow-through electrode processes by AC impedance

    SciTech Connect (OSTI)

    Yuh, C.Y. (Energy Research Corp., Danbury, CT (United States)); Selman, J.R. (Illinois Inst. of Tech., Chicago (United States))

    1993-04-01

    Flow-through porous electrodes, such as packed-bed and fluidized-bed electrodes, are attractive for electrowinning, electro-organic synthesis and flow-battery applications. The extensive surface area of the porous electrodes makes high volumetric reaction rate more possible than in a cell with smooth electrodes. Forced convection also enhances mass-transfer rate and hence reduces concentration polarization. AC-impedance method has been used successfully in characterizing a packed-bed flow-through electrode system. A macrohomogeneous model was developed to simulate the effect of structural, physical and flow parameters. The relative importance of kinetics and mass transfer can be inferred from the AC-impedance analysis. Kinetic information about copper deposition in supported cupric sulfate solution has been obtained successfully using this technique.

  19. 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.

    2011-10-01

    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.

  20. AC Electro-osmotic Flow Induced-charge electro-osmosis, AC pumping of liquids, traveling-wave electro-osmosis.

    E-Print Network [OSTI]

    Bazant, Martin Z.

    AC Electro-osmotic Flow Synonyms Induced-charge electro-osmosis, AC pumping of liquids, traveling-charge electro-osmotic flow around electrodes applying an alternating voltage. Overview Classical electrokinetic phenomena, such as electro-osmotic flow and electrophoresis, are linear in the applied voltage and thus

  1. blogs.lse.ac.uk http://blogs.lse.ac.uk/lsereviewofbooks/2013/06/18/book-review-shaky-foundations-the-politics-patronage-social-science-

    E-Print Network [OSTI]

    Solovey, Mark

    blogs.lse.ac.uk http://blogs.lse.ac.uk/lsereviewofbooks/2013/06/18/book-review-shaky-foundations-the-politics-patronage-social-science- nexus-in-cold-war-america/ by Blog Admin June 18, 2013 Book Review: Shaky Foundations: The Politics

  2. Prof Paul Seakins, Dr Mark Blitz p.w.seakins@leeds.ac.uk phone: 0113 343 6568 http://www.chem.leeds.ac.uk/PWS/

    E-Print Network [OSTI]

    Rzepa, Henry S.

    1 Prof Paul Seakins, Dr Mark Blitz p.w.seakins@leeds.ac.uk phone: 0113 343 6568 http://www.chem.leeds the implications of the work using the Leeds HIRAC chamber (http://www.chem.leeds.ac.uk/hirac-group/) and links to policy can be made through the Leeds Master Chemical Mechanism (MCM). The particular chemical systems

  3. Multiple frequency method for operating electrochemical sensors

    DOE Patents [OSTI]

    Martin, Louis P. (San Ramon, CA)

    2012-05-15

    A multiple frequency method for the operation of a sensor to measure a parameter of interest using calibration information including the steps of exciting the sensor at a first frequency providing a first sensor response, exciting the sensor at a second frequency providing a second sensor response, using the second sensor response at the second frequency and the calibration information to produce a calculated concentration of the interfering parameters, using the first sensor response at the first frequency, the calculated concentration of the interfering parameters, and the calibration information to measure the parameter of interest.

  4. AVTA: Aerovironment AC Level 2 Charging System Testing Results

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The following report describes results from testing done on the Aerovironment AC Level 2 charging system for plug-in electric vehicles. This research was conducted by Idaho National Laboratory.

  5. 8CEN.ACS.ORG APRIL 20, 2015 COVER STORY

    E-Print Network [OSTI]

    .Filter,the"dudeofbrews"atRenegadeBrewingCo.,sportsa gnarlybrownbeardanddrivesadustyblackToyota4Runner. Villa's SandLot brewery sits just past right field in the 50,000-seat Coors Field a velvety imperial stout inside his brewery, surrounded by palettes of empty cans. "Yeast make the beer," he millions of years, chemists and craft brewers congregated a few miles north of the brewery at the ACS

  6. AVTA: Eaton AC Level 2 Charging System Testing Results

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The following report describes results from testing done on the Eaton AC Level 2 charging system for plug-in electric vehicles. This research was conducted by Idaho National Laboratory.

  7. AVTA: Blink AC Level 2 Charging System Testing Results

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The following report describes results from testing done on the Blink AC Level 2 charging system for plug-in electric vehicles. This research was conducted by Idaho National Laboratory.

  8. Atomic filtering for hybrid continuous-variable/discrete-variable quantum optics

    E-Print Network [OSTI]

    Joanna A. Zieli?ska; Federica A. Beduini; Vito Giovanni Lucivero; Morgan W. Mitchell

    2014-09-04

    We demonstrate atomic filtering of frequency-degenerate photon pairs from a sub-threshold optical parametric oscillator (OPO). The filter, a modified Faraday anomalous dispersion optical filter (FADOF), achieves 70% peak transmission simultaneous with 57 dB out-of-band rejection and a 445 MHz transmission bandwidth. When applied to the OPO output, only the degenerate mode, containing one-mode squeezed vacuum, falls in the filter pass-band; all other modes are strongly suppressed. The high transmission preserves non-classical continuous-variable features, e.g. squeezing or non-gaussianity, while the high spectral purity allows reliable discrete-variable detection and heralding. Correlation and atomic absorption measurements indicate a spectral purity of 96% for the individual photons, and 98% for the photon pairs. These capabilities will enable generation of atom-resonant hybrid states, e.g. "Schr\\"odinger kittens" obtained by photon subtraction from squeezed vacuum, making these exotic states available for quantum networking and atomic quantum metrology applications.

  9. Variable focal length deformable mirror

    SciTech Connect (OSTI)

    Headley, Daniel (Albuquerque, NM); Ramsey, Marc (Albuquerque, NM); Schwarz, Jens (Albuquerque, NM)

    2007-06-12

    A variable focal length deformable mirror has an inner ring and an outer ring that simply support and push axially on opposite sides of a mirror plate. The resulting variable clamping force deforms the mirror plate to provide a parabolic mirror shape. The rings are parallel planar sections of a single paraboloid and can provide an on-axis focus, if the rings are circular, or an off-axis focus, if the rings are elliptical. The focal length of the deformable mirror can be varied by changing the variable clamping force. The deformable mirror can generally be used in any application requiring the focusing or defocusing of light, including with both coherent and incoherent light sources.

  10. Space-frequency correlation of classical waves in disordered media: High-frequency and

    E-Print Network [OSTI]

    Fannjiang, Albert

    OFFPRINT Space-frequency correlation of classical waves in disordered media: High-frequency in disordered media: High-frequency and small-scale asymptotics A. C. Fannjiang Department of Mathematics-band high- frequency fields can be appreciably affected by small random changes of the medium parameters

  11. Large Volatility Matrix Inference via Combining Low-Frequency and High-Frequency Approaches

    E-Print Network [OSTI]

    Wang, Yazhen

    Large Volatility Matrix Inference via Combining Low-Frequency and High-Frequency Approaches Minjing adequate estimates and forecasts. Furthermore, since high-frequency financial data for different assets applicable. To overcome those difficulties we explore a novel approach that combines high-frequency

  12. A Universal Hurricane Frequency Function

    E-Print Network [OSTI]

    Ehrlich, Robert

    2010-01-01

    Evidence is provided that the global distribution of tropical hurricanes is principally determined by a universal function H of a single variable z that in turn is expressible in terms of the local sea surface temperature and latitude. The data-driven model presented here carries stark implications for the large increased numbers of hurricanes which it predicts for a warmer world. Moreover, the rise in recent decades in the numbers of hurricanes in the Atlantic, but not the Pacific basin, is shown to have a simple explanation in terms of the specific form of H(z), which yields larger percentage increases when a fixed increase in sea surface temperature occurs at higher latitudes and lower temperatures.

  13. The variability of methane, nitrous oxide and sulfur hexafluoride in Northeast India*

    E-Print Network [OSTI]

    The variability of methane, nitrous oxide and sulfur hexafluoride in Northeast India* A.L. Ganesan of methane, nitrous oxide and sulfur hexafluoride in Northeast India A. L. Ganesan1, A. Chatterjee2, R. G-frequency atmospheric measurements of methane (CH4), nitrous oxide (N2O) and sulfur hexafluo- ride (SF6) from Darjeeling

  14. Tuning the Fluorescence Emission Spectra of a Single Molecule with a Variable Optical Subwavelength Metal Microcavity

    E-Print Network [OSTI]

    Enderlein, Jörg

    Tuning the Fluorescence Emission Spectra of a Single Molecule with a Variable Optical Subwavelength on changing the fluorescence emission spectrum of a single molecule by embedding it within a tunable planar and coupling are both frequency dependent, this leads to a renormalization of the emission spectrum

  15. Variable temperature Raman microscopy as a nanometrology tool for graphene layers and graphene-based devices

    E-Print Network [OSTI]

    Variable temperature Raman microscopy as a nanometrology tool for graphene layers and graphene; accepted 24 July 2007; published online 15 August 2007 Raman microscopy of graphene was carried out over-band frequencies extracted from Raman spectra of the single-layer graphene are - 1.6±0.2 10-2 cm-1 /K and - 3

  16. Energetics of wind-driven barotropic variability in the Southern Ocean

    E-Print Network [OSTI]

    Griesel, Alexa

    Energetics of wind-driven barotropic variability in the Southern Ocean by Wilbert Weijer1-frequency wind forcing. A constant-density, multi-layer model is forced with a band of stochastically varying wind stress. The focus is on the interplay between the surface layer and the interior circulation

  17. Patterns and Scales of Phytoplankton Variability in EstuarineCoastal Ecosystems

    E-Print Network [OSTI]

    next steps of comparative analysis: large year-to-year variability is a response to disturbance from-specific relative importance of disturbance, annual climatology, and nutrient enrichment. Keywords Estuaries, and it is strongly shaped (and biased) by the frequency, duration, and geographic regions of our obser- vations

  18. SYNTHESIS Disturbance-driven changes in the variability of ecological patterns and processes

    E-Print Network [OSTI]

    Fraterrigo, Jennifer

    by considering disturbance extent, frequency and intensity, as well as ecosystem recovery, and thereby capturesREVIEW AND SYNTHESIS Disturbance-driven changes in the variability of ecological patterns Understanding how disturbance shapes the dynamics of ecological systems is of fundamental importance in ecology

  19. System and method for determining stator winding resistance in an AC motor

    DOE Patents [OSTI]

    Lu, Bin (Kenosha, WI); Habetler, Thomas G. (Snellville, GA); Zhang, Pinjia (Atlanta, GA); Theisen, Peter J. (West Bend, WI)

    2011-05-31

    A system and method for determining stator winding resistance in an AC motor is disclosed. The system includes a circuit having an input connectable to an AC source and an output connectable to an input terminal of an AC motor. The circuit includes at least one contactor and at least one switch to control current flow and terminal voltages in the AC motor. The system also includes a controller connected to the circuit and configured to modify a switching time of the at least one switch to create a DC component in an output of the system corresponding to an input to the AC motor and determine a stator winding resistance of the AC motor based on the injected DC component of the voltage and current.

  20. A review of Hurricane Variability

    E-Print Network [OSTI]

    Nadiga, Balasubramanya T. "Balu"

    A review of Hurricane Variability Balu Nadiga, COSIM, LANL, Jun 2006 #12;#12;Key Sources · Kerry Emanuel · Webster 2005 · Elsner 1996 · NASA, NOAA, NCAR · Others #12;Hurricanes, Typhoons, Tropical (because rotation important) #12;Hurricanes: A few Comments · Acts as a heat engine, but with crucial fluid

  1. Phenotypic variability: underlying mechanisms and

    E-Print Network [OSTI]

    Mencuccini, Maurizio

    constraints on growth allocation between tree parts, which affects both primary production (through allocation to transpiring foliage) and net ecosystem production (through allocation to short- lived, easily decomposed fine is reflected in the huge variability in tree form and function across scales. It has been suggested

  2. Operating Reserves and Variable Generation

    SciTech Connect (OSTI)

    Ela, E.; Milligan, M.; Kirby, B.

    2011-08-01

    This report tries to first generalize the requirements of the power system as it relates to the needs of operating reserves. It also includes a survey of operating reserves and how they are managed internationally in system operations today and then how new studies and research are proposing they may be managed in the future with higher penetrations of variable generation.

  3. Integrally formed radio frequency quadrupole

    SciTech Connect (OSTI)

    Abbott, Steven R.

    1989-01-01

    An improved radio frequency quadrupole (10) is provided having an elongate housing (11) with an elongate central axis (12) and top, bottom and two side walls (13a-d) symmetrically disposed about the axis, and vanes (14a-d) formed integrally with the walls (13a-d), the vanes (14a-d) each having a cross-section at right angles to the central axis (12) which tapers inwardly toward the axis to form electrode tips (15a-d) spaced from each other by predetermined distances. Each of the four walls (13a-d), and the vanes (14a-d) integral therewith, is a separate structural element having a central lengthwise plane (16) passing through the tip of the vane, the walls (13a-d) having flat mounting surfaces (17, 18) at right angles to and parallel to the control plane (16), respectively, which are butted together to position the walls and vane tips relative to each other.

  4. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, M.B.; Gardner, D.; Patrick, D.; Lewallen, T.A.; Nammath, S.R.; Painter, K.D.; Vadnais, K.G.

    1996-03-12

    A wide band ground penetrating radar system is described embodying a method wherein a series of radio frequency signals is produced by a single radio frequency source and provided to a transmit antenna for transmission to a target and reflection therefrom to a receive antenna. A phase modulator modulates those portions of the radio frequency signals to be transmitted and the reflected modulated signal is combined in a mixer with the original radio frequency signal to produce a resultant signal which is demodulated to produce a series of direct current voltage signals, the envelope of which forms a cosine wave shaped plot which is processed by a Fast Fourier Transform Unit 44 into frequency domain data wherein the position of a preponderant frequency is indicative of distance to the target and magnitude is indicative of the signature of the target. 6 figs.

  5. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, Michael B. (Buellton, CA); Gardner, Duane (Santa Maria, CA); Patrick, Douglas (Santa Maria, CA); Lewallen, Tricia A. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA); Painter, Kelly D. (Goleta, CA); Vadnais, Kenneth G. (Alexandria, VA)

    1996-01-01

    A wide band ground penetrating radar system (10) embodying a method wherein a series of radio frequency signals (60) is produced by a single radio frequency source (16) and provided to a transmit antenna (26) for transmission to a target (54) and reflection therefrom to a receive antenna (28). A phase modulator (18) modulates those portion of the radio frequency signals (62) to be transmitted and the reflected modulated signal (62) is combined in a mixer (34) with the original radio frequency signal (60) to produce a resultant signal (53) which is demodulated to produce a series of direct current voltage signals (66) the envelope of which forms a cosine wave shaped plot (68) which is processed by a Fast Fourier Transform unit 44 into frequency domain data (70) wherein the position of a preponderant frequency is indicative of distance to the target (54) and magnitude is indicative of the signature of the target (54).

  6. Frequency Control Performance Measurement and Requirements

    SciTech Connect (OSTI)

    Illian, Howard F.

    2010-12-20

    Frequency control is an essential requirement of reliable electric power system operations. Determination of frequency control depends on frequency measurement and the practices based on these measurements that dictate acceptable frequency management. This report chronicles the evolution of these measurements and practices. As technology progresses from analog to digital for calculation, communication, and control, the technical basis for frequency control measurement and practices to determine acceptable performance continues to improve. Before the introduction of digital computing, practices were determined largely by prior experience. In anticipation of mandatory reliability rules, practices evolved from a focus primarily on commercial and equity issues to an increased focus on reliability. This evolution is expected to continue and place increased requirements for more precise measurements and a stronger scientific basis for future frequency management practices in support of reliability.

  7. Prediction of spectral shifts proportional to source distances by time-varying frequency or wavelength selection

    E-Print Network [OSTI]

    V. Guruprasad

    2008-12-04

    Any frequency selective device with an ongoing drift will cause observed spectra to be variously and simultaneously scaled in proportion to their source distances. The reason is that detectors after the drifting selection will integrate instantaneous electric or magnetic field values from successive sinusoids, and these sinusoids would differ in both frequency and phase. Phase differences between frequencies are ordinarily irrelevant, and recalibration procedures at most correct for frequency differences. With drifting selection, however, each integrated field value comes from *the sinusoid of the instantaneously selected frequency at its instantaneous received phase*, hence the waveform constructed by the integration will follow the drifting selection with a phase acceleration given by the drift rate times the slope of the received phase spectrum. A phase acceleration is literally a frequency shift, and the phase spectrum slope of a received waveform is an asymptotic measure of the source distance, as the path delay presents phase offsets proportional to frequency times the distance, and eventually exceeding all initial phase differences. Tunable optics may soon be fast enough for realizing such shifts by Fourier switching, and could lead to pocket X-ray devices; sources continuously variable from RF to gamma rays; capacity multiplication with jamming and noise immunity in both fibre and radio channels, passive ranging from ground to deep space; etc.

  8. Frequency spectrum analyzer with phase-lock

    DOE Patents [OSTI]

    Boland, Thomas J. (Idaho Falls, ID)

    1984-01-01

    A frequency-spectrum analyzer with phase-lock for analyzing the frequency and amplitude of an input signal is comprised of a voltage controlled oscillator (VCO) which is driven by a ramp generator, and a phase error detector circuit. The phase error detector circuit measures the difference in phase between the VCO and the input signal, and drives the VCO locking it in phase momentarily with the input signal. The input signal and the output of the VCO are fed into a correlator which transfers the input signal to a frequency domain, while providing an accurate absolute amplitude measurement of each frequency component of the input signal.

  9. Multiple frequency printed slot and dipole antennas 

    E-Print Network [OSTI]

    Kolsrud, Arild

    1997-01-01

    frequencies. Adding one varactor diode to the slot antenna or two diodes to the dipole either switching or tuning of the antenna could be achieved....

  10. Method and apparatus for monitoring the rotating frequency of de-energized induction motors

    DOE Patents [OSTI]

    Mikesell, Harvey E. (McMurray, PA); Lucy, Eric (Murrysville, PA)

    1998-01-01

    The rotational speed of a coasting induction motor is measured by sensing e residual electrical voltages at the power terminals of the motor, thus eliminating the need for conventional tachometer equipment, additional mechanical components or modifications to the induction motor itself. The power terminal voltage signal is detected and transformed into a DC voltage proportional to the frequency of the signal. This DC voltage can be input to the control system of a variable frequency motor controller to regulate the output characteristics thereof relative to the speed of the coasting motor.

  11. Variability Aware Network Utility Maximization

    E-Print Network [OSTI]

    Joseph, Vinay

    2011-01-01

    Network Utility Maximization (NUM) provides the key conceptual framework to study resource allocation amongst a collection of users/entities across disciplines as diverse as economics, law and engineering. In network engineering, this framework has been particularly insightful towards understanding how Internet protocols allocate bandwidth, and motivated diverse research on distributed mechanisms to maximize network utility while incorporating new relevant constraints, on energy/power, storage, stability, etc., for systems ranging from communication networks to the smart-grid. However when the available resources and/or users' utilities vary over time, a user's allocations will tend to vary, which in turn may have a detrimental impact on the users' utility or quality of experience. This paper introduces a generalized NUM framework which explicitly incorporates the detrimental impact of temporal variability in a user's allocated rewards. It explicitly incorporates tradeoffs amongst the mean and variability in ...

  12. Massive Variability Surveys from Venezuela

    E-Print Network [OSTI]

    Cesar Briceno

    2003-04-03

    At the Venezuela National Astronomical Observatory we are carrying out variability surveys spanning many hundreds of square degrees near the celestial equator, using an 8k x 8k CCD Mosaic Camera optimized for drift-scanning on a 1m Schmidt telescope. Among the initial efforts was a project to obtain the first moderately deep, homogeneous sample of young stars over an area of ~180sqr.deg. encompassing the entire Orion OB1 association, one of the nearest and most active regions of star formation. The results show that variability is a powerful technique to identify pre-main sequence populations, specially in sparse areas devoid of gas and dust. We are currently developing a massive database, equipped with web-based data mining tools, that will make our data and results available to the astronomical community.

  13. A precision millimeter-wave measurement of the Rydberg frequency

    E-Print Network [OSTI]

    De Vries, Joel Christopher, 1971-

    2001-01-01

    The Rydberg frequency, cR[infinity], sets the frequency scale for the spectrum of hydrogen atoms. From a frequency measurement of one transition in hydrogen, cR[infinity] can be extracted and the frequency of any other ...

  14. DE-AC05-06OR23100 Section H

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent Bonding inCustomer-Comments Sign InTAMUiv e64001466AC05-06OR23100

  15. Histograms detect imbalances Variable sizes capture variance

    E-Print Network [OSTI]

    Mueller, Frank

    Laboratory, North Carolina State University, Renaissance Computing Institute This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52, Profiler, Child Nodes Data Output: to Parent Node, Tool Communication paths OPS Attr.1 Attr.2 Attr

  16. Variable Speed Wind Turbine Generator with Zero-sequence Filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-08-25

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  17. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-01-01

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  18. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, E.

    1998-08-25

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility. 14 figs.

  19. Low frequency noise in superconducting qubits

    E-Print Network [OSTI]

    Fominov, Yakov

    Low frequency noise in superconducting qubits Lara Faoro and Lev Ioffe Rutgers University (USA) Exp-traps Faoro and Ioffe, PRL 96, 47001 (2006) · a discussion on the mysterious and puzzling flux noise at low... IN PROGRESS WITH EXPERIMENTALISTS! 4. Origin of low frequency flux noise at low temperature ? WHAT THE HELL

  20. Low Frequency Transmission Final Project Report

    E-Print Network [OSTI]

    Low Frequency Transmission Final Project Report Power Systems Engineering Research Center Empowering Minds to Engineer the Future Electric Energy System #12;Low Frequency Transmission Final Project This is the final report for the Power Systems Engineering Research Center (PSERC) research project S-42 titled "Low

  1. Multi-dimensional ultra-high frequency passive radio frequency identification tag antenna designs

    E-Print Network [OSTI]

    Delichatsios, Stefanie Alkistis

    2006-01-01

    In this thesis, we present the design, simulation, and empirical evaluation of two novel multi-dimensional ultra-high frequency (UHF) passive radio frequency identification (RFID) tag antennas, the Albano-Dipole antenna ...

  2. Bright six-partite continuous variable entanglement using cascaded four-wave mixing processes in a four-level atomic system

    E-Print Network [OSTI]

    Guangqiang He; Xufei Wu; Yi Gu

    2011-09-10

    We theoretically show that bright six-partite continuous-variable entanglement can be generated using cascaded four-wave mixing effects of third-order nonlinearity atomic systems above threshold. The six-partite continuous-variable entanglement among the six cavity fields with different frequencies is analyzed by applying optimized inseparability criteria proposed by Van Loock and Furusawa.

  3. IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 40, NO. 2, MARCH/APRIL 2004 565 Modeling and Control of a Variable-Speed

    E-Print Network [OSTI]

    Mi, Chunting "Chris"

    and Control of a Variable-Speed Constant-Frequency Synchronous Generator With Brushless Exciter Chunting Mi. The main generator is a doubly fed induction machine which is operated as a synchronous generator-magnet exciter, synchronous generator excitation, synchronous generators, variable-speed constant

  4. Peccei-Quinn axions from frequency dependence radiation dimming

    E-Print Network [OSTI]

    Raul Jimenez; Carlos Pena-Garay; Licia Verde

    2011-02-08

    We explore how the Peccei-Quinn (PQ) axion parameter space can be constrained by the frequency-dependence dimming of radiation from astrophysical objects. To do so we perform accurate calculations of photon-axion conversion in the presence of a variable magnetic field. We propose several tests where the PQ axion parameter space can be explored with current and future astronomical surveys: the observed spectra of isolated neutron stars, occultations of background objects by white dwarfs and neutron stars, the light curves of eclipsing binaries containing a white dwarf. We find that the lack of dimming of the light curve of a detached eclipsing white dwarf binary recently observed, leads to relevant constraints on the photon-axion conversion. Current surveys designed for Earth-like planet searches are well matched to strengthen and improve the constraints on the PQ axion using astrophysical objects radiation dimming.

  5. s.haszeldine@ed.ac.uk Scottish Centre for Carbon Storage, Petrobras 2008 1 University of Edinburgh (est 1583)

    E-Print Network [OSTI]

    Haszeldine, Stuart

    volumes Reservoir engineering, Risk, Public acceptance #12;s.haszeldine@ed.ac.uk Scottish Centre companies s.haszeldine@ed.ac.uk Scottish Centre for Carbon Storage, Petrobras 2008 8 3: Example PhD work CCS

  6. A Generalized Class of Stationary Frame-Current Controllers for Grid-Connected AC–DC Converters

    E-Print Network [OSTI]

    Hwang, J. George

    Within power systems, high-power pulsewidth-modulated ac-dc converters are used in flexible ac transmission systems controllers and for interfacing renewable energy sources to the grid. These converters traditionally ...

  7. A nonlinear robust HVDC control for a parallel AC/DC power system

    E-Print Network [OSTI]

    Qu, Zhihua

    recognized that, through an HVDC transmission line, fast electronic control can be applied on the DC power, controlling DC line transmission power can improve stability of the AC system after a major disturbanceA nonlinear robust HVDC control for a parallel AC/DC power system Hongzhi Cai a , Zhihua Qu b

  8. 80 IAEI NEWS May . June 2012 www.iaei.org Microinverters and ac Pv Modules

    E-Print Network [OSTI]

    Johnson, Eric E.

    80 IAEI NEWS May . June 2012 www.iaei.org Microinverters and ac Pv Modules M icroinverters and AC PV modules are becom- ing very common in residential and small commercial PV systems. See photos 1 and 2. They have even been used in PV systems rated at 60 kW and above. They have some common features

  9. Aalborg Universitet Optimal Selection of AC Cables for Large Scale Offshore Wind Farms

    E-Print Network [OSTI]

    Hu, Weihao

    Aalborg Universitet Optimal Selection of AC Cables for Large Scale Offshore Wind Farms Hou, Peng Cables for Large Scale Offshore Wind Farms. In Proceedings of the 40th Annual Conference of IEEE of AC Cables for Large Scale Offshore Wind Farms Peng Hou, Weihao Hu, Zhe Chen Department of Energy

  10. Fast ac electro-osmotic micropumps with nonplanar electrodes John Paul Urbanski and Todd Thorsena

    E-Print Network [OSTI]

    Bazant, Martin Z.

    Fast ac electro-osmotic micropumps with nonplanar electrodes John Paul Urbanski and Todd Thorsena range over conventional planar ac electro-osmotic ACEO pumps by exploiting three-dimensional 3D stepped to ad- dress these drawbacks by developing microfluidic pumps based on nonlinear electro-osmotic flow

  11. Fast Marching farthest point sampling Carsten Moenning (cm230@cl.cam.ac.uk)

    E-Print Network [OSTI]

    Dodgson, Neil

    Fast Marching farthest point sampling Carsten Moenning (cm230@cl.cam.ac.uk) Neil A. Dodgson (nad@cl.cam.ac.uk) Introduction We introduce the Fast Marching farthest point sampling (FastFPS) approach for the progressive sampling of planar domains and curved manifolds in triangulated, point cloud or implicit form. We use Fast

  12. Power control of a wind farm with active stall wind turbines and AC grid connection

    E-Print Network [OSTI]

    Power control of a wind farm with active stall wind turbines and AC grid connection Anca D. Hansen1 on the wind farm level. The ability of active stall wind farms with AC grid connection to regulate the power, is therefore directed towards optimising the integration of large wind farms within the electrical power grid

  13. Study of Ionic Conductivity Profiles of the Air Cathode of a PEMFC by AC Impedance Spectroscopy

    E-Print Network [OSTI]

    Study of Ionic Conductivity Profiles of the Air Cathode of a PEMFC by AC Impedance Spectroscopy membrane fuel cell PEMFC cathode by ac impedance measurement at open-circuit potential conditions membrane fuel cell PEMFC .1 The function of a proton-conducting ionomer such as Nafion® is to provide

  14. www.climate.iitb.ac.in 1st CLIMATE SCIENCE AND

    E-Print Network [OSTI]

    Sarawagi, Sunita

    www.climate.iitb.ac.in 1st CLIMATE SCIENCE AND POLICY WORKSHOP (CSPW)(CSPW) 6th & 7th March, 2014 a scientific understanding of regional climate change and connect it to impacts and effective response. www.climate.iitb.ac.in #12;Interdisciplinary Programme in Climate Studies Indian Institute of Technology Bombay The Climate

  15. Combinations of Modal Logics Brandon Bennett (brandon@scs.leeds.ac.uk)

    E-Print Network [OSTI]

    Franconi, Enrico

    Combinations of Modal Logics #3; Brandon Bennett (brandon@scs.leeds.ac.uk) School of Computer Studies, University of Leeds, UK Clare Dixon (c.dixon@doc.mmu.ac.uk), Michael Fisher (m. However, we begin by reviewing why we might want to use modal logics at all. #3; This document

  16. 10/18/05 AIChE/ACS New Haven 1 Microchemical Systems for Current

    E-Print Network [OSTI]

    Besser, Ronald S.

    H2 Generation · Example: Pharmaceutical Hydrogenation · Conclusions · Acknowledgements #12;2 10 power, pharmaceutical, and chemical applications #12;3 10/18/05 AIChE/ACS New Haven 5 MicrochemicalE/ACS New Haven 6 Key Benefit: Surface to Volume SA Increasing V Constant Heat Management Mixing Surface

  17. Harnessing the power of Deep Learning :sromanka@tx.technion.ac.il Roman Kaplan

    E-Print Network [OSTI]

    Cidon, Israel

    " Harnessing the power of Deep Learning :sromanka@tx.technion.ac.il Roman Kaplan The hottest topic the exact application 2. We think how to implement the right system. 3. We (mostly you) chooseReduce, Hadoop/Spark/GraphLab. Use Machine Learning for Your Desired Purpose :sromanka@tx.technion.ac.il Roman

  18. Improving health worldwide www.lshtm.ac.uk Excellence in Public Health

    E-Print Network [OSTI]

    Maizels, Rick

    Improving health worldwide www.lshtm.ac.uk Excellence in Public Health & Policy Faculty of Public Health and Policy Strategy 2012-17 #12;2 Improving health worldwide www.lshtm.ac.uk Introduction & purpose The Faculty of Public Health & Policy is prominent in UK and global health, influencing policy

  19. Definition of a Random Variable Distribution Functions Properties of Distribution Functions Random Variables and Distribution Functions

    E-Print Network [OSTI]

    Watkins, Joseph C.

    Definition of a Random Variable Distribution Functions Properties of Distribution Functions Topic 7 Random Variables and Distribution Functions Distribution Functions 1 / 11 #12;Definition of a Random Variable Distribution Functions Properties of Distribution Functions Outline Definition of a Random

  20. Further Results on Distributed Secondary Control in Microgrids Hedi Bouattour, John W. Simpson-Porco, Florian Dorfler, and Francesco Bullo

    E-Print Network [OSTI]

    Bullo, Francesco

    , heterogeneously composed of distributed generation, storage, load, and managed autonomously from the larger, geothermal, micro-turbines, etc. Many of these sources generate either variable frequency AC power or DC power, and are interfaced with a synchronous AC grid via power electronic DC/AC inverters. In islanded

  1. Modeling a Complex Pole-Zero System in Terms of its Low-Frequency/High-Frequency Cutoffs

    E-Print Network [OSTI]

    King, Roger

    Modeling a Complex Pole-Zero System in Terms of its Low-Frequency/High-Frequency Cutoffs Introduction Even a simple amplifier circuit will tend to have multiple poles and zeros in its high-frequency will alter a signal can be gotten from its high-frequency and low-frequency cutoffs. High-Frequency Response

  2. 22 IAEI NEWS March.April 2010 www.iaei.org the microinverter and the ac pv module

    E-Print Network [OSTI]

    Johnson, Eric E.

    22 IAEI NEWS March.April 2010 www.iaei.org the microinverter and the ac pv module by John Wiles The Microinverter and the AC PV Module The Microinverter and the AC PV Module 22 IAEI NEWS March.April 2010 www.iaei.org #12;www.iaei.org March.April 2010 IAEI NEWS 23 the microinverter and the ac pv module Microinverters

  3. The Cloud Computing and Other Variables

    E-Print Network [OSTI]

    Borjon-Kubota, Martha Estela

    2011-01-01

    12. Fragments in Six 13. Cloud Computing 14. Phase 15.Note 48. Devoured vi Cloud Computing and other Variables I.CALIFORNIA RIVERSIDE Cloud Computing and Other Variables A

  4. Characterization of Cardio signals by time-frequency domain analysis

    E-Print Network [OSTI]

    Sayan Mukherjee; Sanjay Kumar Palit; Santo Banerjee; MRK Ariffin; Lamberto Rondoni; Dilip Kumar Bhattacharya

    2014-09-04

    Long term behavior of nonlinear deterministic continuous time signals can be studied in terms of their reconstructed attractors. Reconstructed attractors of a continuous signal are meant to be topologically equivalent representations of the dynamics of the unknown dynamical system which generates the signal. Sometimes, geometry of the attractor or its complexity may give important information on the system of interest. However, if the trajectories of the attractor behave as if they are not coming from continuous system or there exists many spike like structures on the path of the system trajectories, then there is no way to characterize the shape of the attractor. In this article, the traditional attractor reconstruction method is first used for two types of ECG signals: Normal healthy persons (NHP) and Congestive Heart failure patients (CHFP). As common in such a framework, the reconstructed attractors are not at all well formed and hence it is not possible to adequately characterize their geometrical features. Thus, we incorporate frequency domain information to the given time signals. This is done by transforming the signals to a time frequency domain by means of suitable Wavelet transforms (WT). The transformed signal concerns two non homogeneous variables and is still quite difficult to use to reconstruct some dynamics out of it. By applying a suitable mapping, this signal is further converted into integer domain and a new type of 3D plot, called integer lag plot, which characterizes and distinguishes the ECG signals of NHP and CHFP, is finally obtained.

  5. Harnessing high-dimensional hyperentanglement through a biphoton frequency comb

    E-Print Network [OSTI]

    Zhenda Xie; Tian Zhong; Sajan Shrestha; XinAn Xu; Junlin Liang; Yan-Xiao Gong; Joshua C. Bienfang; Alessandro Restelli; Jeffrey H. Shapiro; Franco N. C. Wong; Chee Wei Wong

    2015-06-13

    Quantum entanglement is a fundamental resource for secure information processing and communications, where hyperentanglement or high-dimensional entanglement has been separately proposed towards high data capacity and error resilience. The continuous-variable nature of the energy-time entanglement makes it an ideal candidate for efficient high-dimensional coding with minimal limitations. Here we demonstrate the first simultaneous high-dimensional hyperentanglement using a biphoton frequency comb to harness the full potential in both energy and time domain. The long-postulated Hong-Ou-Mandel quantum revival is exhibited, with up to 19 time-bins, 96.5% visibilities. We further witness the high-dimensional energy-time entanglement through Franson revivals, which is observed periodically at integer time-bins, with 97.8% visibility. This qudit state is observed to simultaneously violate the generalized Bell inequality by up to 10.95 deviations while observing recurrent Clauser-Horne-Shimony-Holt S-parameters up to 2.76. Our biphoton frequency comb provides a platform in photon-efficient quantum communications towards the ultimate channel capacity through energy-time-polarization high-dimensional encoding.

  6. Variability of modal parameters measured on the Alamosa Canyon Bridge

    SciTech Connect (OSTI)

    Farrar, C.R.; Doebling, S.W. [Los Alamos National Lab., NM (United States); Cornwell, P.J.; Straser, E.G. [Stanford Univ., CA (United States). J.A. Blume Earthquake Engineering Center

    1996-12-31

    A significant amount of work has been reported in technical literature regarding the use of changes in modal parameters to identify the location and extent of damage in structures. Curiously absent, and critically important to the practical implementation of this work, is an accurate characterization of the natural variability of these modal parameters caused by effects other than damage. To examine this issue, a two-lane, seven-span, composite slab-on-girder bridge near the town of Truth or Consequences in southern New Mexico was tested several times over a period of nine months. Environmental effects common to this location that could potentially produce changes in the measured modal properties include changes in temperature, high winds, and changes to the supporting soil medium. In addition to environmental effects, variabilities in modal testing procedures and data reduction can also cause changes in the identified dynamic properties of the structure. In this paper the natural variability of the frequencies and mode shapes of the Alamosa Canyon bridge that result from changes in time of day when the test was performed, amount of traffic, and environmental conditions will be discussed. Because this bridge has not been in active use throughout the testing period, it is assumed that any change in the observed modal properties are the result of the factors listed above rather than deterioration of the structure itself.

  7. Long term variability of the blazar PKS 2155-304

    E-Print Network [OSTI]

    Chevalier, Jill; Rieger, Frank; Maurin, Gilles; Lenain, Jean-Philippe; Lamanna, Giovanni

    2015-01-01

    Time variability of the photon flux is a known feature of active galactic nuclei (AGN) and in particular of blazars. The high frequency peaked BL Lac (HBL) object PKS 2155-304 is one of the brightest sources in the TeV band and has been monitored regularly with different instruments and in particular with the H.E.S.S. experiment above 200 GeV for more than 11 years. These data together with the observations of other instruments and monitoring programs like SMARTS (optical), Swift-XRT/RXTE/XMM-Newton (X-ray) and Fermi-LAT (100 MeV energy range. Variability studies are made by looking at the lognormality of the light curves and at the fractional root mean square (rms) variability Fvar in several energy bands. Lognormality is found in every energy range and the evolution of Fvar with the energy shows a similar increase both in X-rays and in TeV bands.

  8. 1620 IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 27, NO. 3, JULY 2012 Hybrid AC/DC Transmission Expansion Planning

    E-Print Network [OSTI]

    Fu, Yong

    1620 IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 27, NO. 3, JULY 2012 Hybrid AC/DC Transmission--This paper proposes a hybrid algorithm for the ac/dc transmission expansion planning (TEP). The stochastic simulation method would consider random outages of generating units and ac/dc transmission lines as well

  9. http://www.up.ac.za/academic/fabi/tpcp/pamphlets/submission.htm SUBMISSION OF SAMPLES FOR DISEASE DIAGNOSIS

    E-Print Network [OSTI]

    http://www.up.ac.za/academic/fabi/tpcp/pamphlets/submission.htm SUBMISSION OF SAMPLES FOR DISEASE of your http://www.up.ac.za/academic/fabi/tpcp/pamphlets/submission.htm (1 of 2) [2002/02/26 01:55:27] #12;http://www.up.ac.za/academic/fabi/tpcp/pamphlets/submission.htm TYPES OF SAMPLES Samples for laboratory

  10. Thermoacoustic and Photoacoustic Tomography with a variable ...

    E-Print Network [OSTI]

    Plamen Stefanov

    2010-11-09

    ... a joint work with. Jianliang Qian, Gunther Uhlmann and Hongkai Zhao. Plamen Stefanov (Purdue University ). Thermoacoustic Tomography, Variable Speed.

  11. The frequency spectrum of the Casimir effect

    SciTech Connect (OSTI)

    Lang, Andrew S.I.D. [Computer Science and Mathematics Department, Oral Roberts University, Tulsa, Oklahoma 74171 (United States)

    2005-10-01

    The frequency spectrum of the Casimir effect between parallel plates is studied. Calculations are performed for both the massless scalar field and the electromagnetic field cases, first using a spectral weight function, and then via the Fourier transform of the renormalized expectation of the Casimir energy-momentum operator. The Casimir force is calculated using the spectrum for two plates which are perfectly transparent in a frequency band. The result of this calculation suggests a way to detect the frequency spectrum of the Casimir effect.

  12. Multi-mode radio frequency device

    DOE Patents [OSTI]

    Gilbert, Ronald W. (Morgan Hill, CA); Carrender, Curtis Lee (Morgan Hill, CA); Anderson, Gordon A. (Benton City, WA); Steele, Kerry D. (Kennewick, WA)

    2007-02-13

    A transponder device having multiple modes of operation, such as an active mode and a passive mode, wherein the modes of operation are selected in response to the strength of a received radio frequency signal. A communication system is also provided having a transceiver configured to transmit a radio frequency signal and to receive a responsive signal, and a transponder configured to operate in a plurality of modes and to activate modes of operation in response to the radio frequency signal. Ideally, each mode of operation is activated and deactivated independent of the other modes, although two or more modes may be concurrently operational.

  13. High power radio frequency attenuation device

    DOE Patents [OSTI]

    Kerns, Quentin A. (Bloomingdale, IL); Miller, Harold W. (Winfield, IL)

    1984-01-01

    A resistor device for attenuating radio frequency power includes a radio frequency conductor connected to a series of fins formed of high relative magnetic permeability material. The fins are dimensional to accommodate the skin depth of the current conduction therethrough, as well as an inner heat conducting portion where current does not travel. Thermal connections for air or water cooling are provided for the inner heat conducting portions of each fin. Also disclosed is a resistor device to selectively alternate unwanted radio frequency energy in a resonant cavity.

  14. Turbine bucket natural frequency tuning rib

    DOE Patents [OSTI]

    Wang, John Zhiqiang (Greenville, SC); Norton, Paul Francis (Greenville, SC); Barb, Kevin Joseph (Halfmoon, NY); Jacala, Ariel Caesar-Prepena (Simpsonville, SC)

    2002-01-01

    A tuning rib is added preferably in the aft cavity of a cored turbine bucket to alter the bucket's natural frequencies. The tuning rib may be a solid rib or a segmented rib and is particularly suited for altering high order frequency modes such as 2T, 4F and 1-3S. As such, detrimental crossings of natural bucket frequencies and gas turbine stimuli can be avoided to thereby improve the reliability of a gas turbine without impacting other features of the bucket that are important to the performance of the gas turbine.

  15. Limits in high efficiency quantum frequency conversion

    E-Print Network [OSTI]

    Nicolás Quesada; J. E. Sipe

    2015-08-13

    Frequency conversion is an enabling process in many quantum information protocols. In this letter we study fundamental limits to high efficiency frequency conversion imposed by time ordering corrections. Using the Magnus expansion, we argue that these corrections, which are usually considered detrimental, can be used to increase the efficiency of conversion under certain circumstances. The corrections induce a nonlinear behaviour in the probability of upconversion as a function of the pump intensity, significantly modifying the sinusoidal Rabi oscillations that are otherwise expected. Finally, by using a simple scaling argument, we explain why cascaded frequency conversion devices attenuate time ordering corrections, allowing the construction of near ideal quantum pulse gates.

  16. Frequency(#Seedlings&Saplings) Substrate Cover (%)

    E-Print Network [OSTI]

    Brown, Sally

    30 35 40 0-10 11-20 21-30 31-40 41-50 51-60 61-70 Frequency Basal Area Bins (m2/ha) All Species 0 5 10 15 20 25 30 35 40 0-10 11-20 21-30 31-40 41-50 51-60 60-100 Frequency Basal Area Bins (m2/ha) P. menziesii 0 5 10 15 20 25 30 35 40 45 0-10 11-20 21-30 31-40 41-50 51-60 60-100 Frequency Basa Area Bins (m2

  17. AC transmission system planning choosing lines from a discrete set

    E-Print Network [OSTI]

    Gilbertson, Eric W.

    2013-04-24

    Transmission system planning (TSP) is a difficult nonlinear optimization problem involving non-convex quadratic terms, as well as discrete variables. We extend prior results for linear relaxations, drawing on a preliminary ...

  18. Variability-aware system-level design and analysis

    E-Print Network [OSTI]

    Chandra, Saumya

    2009-01-01

    Voltage-Frequency Island Systems,” in Proc. Int. Conf.in multi-voltage island systems) have different frequency-Frequency Island Latency-Constrained Systems,” IEEE Trans.

  19. Security approaches for Radio Frequency Identification systems

    E-Print Network [OSTI]

    Foley, Joseph Timothy, 1976-

    2007-01-01

    In this thesis, I explore the challenges related to the security of the Electronic Product Code (EPC) class of Radio Frequency Identification (RFID) tags and associated data. RFID systems can be used to improve supply chain ...

  20. Very-High-Frequency Resonant Boost Converters

    E-Print Network [OSTI]

    Perreault, David J.

    This paper presents a resonant boost topology suitable for very-high-frequency (VHF, 30-300 MHz) DC-DC power conversion. The proposed design features low device voltage stress, high efficiency over a wide load range, and ...

  1. Developing high-frequency equities trading models

    E-Print Network [OSTI]

    Infantino, Leandro Rafael

    2010-01-01

    The purpose of this paper is to show evidence that there are opportunities to generate alpha in the high frequency environment of the US equity market, using Principal Component Analysis (PCA hereafter) as a basis for short ...

  2. Characterization of arcs in frequency domain

    SciTech Connect (OSTI)

    D'Inca, R.; Siegl, G.; Faugel, H.; Braun, F.; Eckert, B.; Bobkov, V.; El Khaldi, M.; Noterdaeme, J.-M.

    2009-11-26

    Arc detection systems are developed for ICRH on ITER to prevent arcs from damaging the RF components. One of the detectors, the Sub-Harmonic Arc Detector (SHAD) is based on the detection of the frequencies emitted in the MHz range by arcs [R1]. To ensure the high level of reliability required for this safety system, it is necessary to demonstrate that these frequencies present a signal with a Signal to Noise Ratio high enough to be detected under the wide range of operational conditions (frequency, power, configuration) and for the different types of arcs that can appear in the feeding lines and on the antennas (vacuum arc, glow discharge, multipactor-induced discharge). For each type of arc, we analyze the evolution of the frequency spectrum relative to the evolution of other electrical parameters (reflected power, voltage)

  3. Radio frequency dc-dc power conversion

    E-Print Network [OSTI]

    Rivas, Juan, 1976-

    2007-01-01

    THIS THESIS addresses the development of system architectures and circuit topologies for dc-dc power conversion at very high frequencies. The systems architectures that are developed are structured to overcome limitations ...

  4. Frequency-feedback cavity enhanced spectrometer

    DOE Patents [OSTI]

    Hovde, David Christian; Gomez, Anthony

    2015-08-18

    A spectrometer comprising an optical cavity, a light source capable of producing light at one or more wavelengths transmitted by the cavity and with the light directed at the cavity, a detector and optics positioned to collect light transmitted by the cavity, feedback electronics causing oscillation of amplitude of the optical signal on the detector at a frequency that depends on cavity losses, and a sensor measuring the oscillation frequency to determine the cavity losses.

  5. A Compressible Reconfigurable Frequency Selective Surface 

    E-Print Network [OSTI]

    Li, Shuli

    2015-05-11

    my gratitude to the U.S. National Science Foundation for their support. Finally, thanks to my mother and father for their encouragement and love. v NOMENCLATURE FSS Frequency Selective Surface RF Radio Frequency MEMS Microelectromechanical... devices and circuits in the field of RF and microwave wireless systems. There are typically two different methods of tuning components and methods. The first method is using tuning elements like PIN diodes and microelectromechanical system (MEMS...

  6. Frequency domain design of interval controller 

    E-Print Network [OSTI]

    Park, Wunyong

    1993-01-01

    Subject: Electrical Engineering FREQUENCY DOMAIN DFSIGN OF INTERVAL CONTROLLER A Thesis by WUNYONG PARK Approved as to style and content by: S. P. Bhattacharyyd (Chair of Committee) C. N. Georghiades (Member) A. Datta (Member) S. Jayasuriya... (Member) . H. Keel (Member) A. Patton (Head of Department) May 1993 111 ABSTRACT Frequency Domain Design of Interval Controller. (May 1993) Wunyong Park, B. S. , Yon Sei University; M. S. , Yon Sei University Chair of Advisory Committee: Dr. S...

  7. Extremely high frequency RF effects on electronics.

    SciTech Connect (OSTI)

    Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

    2012-01-01

    The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

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

    E-Print Network [OSTI]

    Gopman, Daniel B; Kent, Andrew D

    2012-01-01

    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.

  9. Continuous Variable Quantum Information Processing

    E-Print Network [OSTI]

    Ulrik L. Andersen; Gerd Leuchs; Christine Silberhorn

    2010-08-20

    Observables of quantum systems can posses either a discrete or a continuous spectrum. For example, upon measurements of the photon number of a light state, discrete outcomes will result whereas measurements of the light's quadrature amplitudes result in continuous outcomes. If one uses the continuous degree of freedom of a quantum system either for encoding, processing or detecting information, one enters the field of continuous variable (CV) quantum information processing. In this paper we review the basic principles of CV quantum information processing with main focus on recent developments in the field. We will be addressing the three main stages of a quantum informational system; the preparation stage where quantum information is encoded into CVs of coherent states and single photon states, the processing stage where CV information is manipulated to carry out a specified protocol and a detection stage where CV information is measured using homodyne detection or photon counting.

  10. Variable delivery, fixed displacement pump

    DOE Patents [OSTI]

    Sommars, Mark F. (Sparland, IL)

    2001-01-01

    A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.

  11. Continuously variable focal length lens

    DOE Patents [OSTI]

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  12. Microlensing induced absorption line variability

    E-Print Network [OSTI]

    Geraint F. Lewis; Rodrigo A. Ibata

    2002-12-02

    Gravitational microlensing has proven to be a powerful probe of both the structure at the heart of quasars and the mass function of compact objects in foreground lenses. This paper examines the potential of gravitational microlensing in probing the scale of structure in absorbing material within the lensing galaxy. We find that, in this high optical depth regime, significant variations in the equivalent width of absorption features can be induced, although the details of these are dependent upon the scale of structure of the absorbing material. The paper concludes with an examination of the absorption line variability observed in the gravitationally lensed quasar PKS1830-211, demonstrating how this may indicate the presence of small scale structure in the cold molecular gas present within the lensing galaxy.

  13. Variable ratio regenerative braking device

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1981-12-15

    Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

  14. ISM band to U-NII band frequency transverter and method of frequency transversion

    DOE Patents [OSTI]

    Stepp, Jeffrey David (Grandview, MO); Hensley, Dale (Grandview, MO)

    2006-09-12

    A frequency transverter (10) and method for enabling bi-frequency dual-directional transfer of digitally encoded data on an RF carrier by translating between a crowded or otherwise undesirable first frequency band, such as the 2.4 GHz ISM band, and a less-crowded or otherwise desirable second frequency band, such as the 5.0 GHz 6.0 GHz U-NII band. In a preferred embodiment, the transverter (10) connects between an existing data radio (11) and its existing antenna (30), and comprises a bandswitch (12); an input RF isolating device (14); a transmuter (16); a converter (18); a dual output local oscillator (20); an output RF isolating device (22); and an antenna (24) tuned to the second frequency band. The bandswitch (12) allows for bypassing the transverter (10), thereby facilitating its use with legacy systems. The transmuter (14) and converter (16) are adapted to convert to and from, respectively, the second frequency band.

  15. ISM band to U-NII band frequency transverter and method of frequency transversion

    DOE Patents [OSTI]

    Stepp, Jeffrey David (Grandview, MO); Hensley, Dale (Grandview, MO)

    2006-04-04

    A frequency transverter (10) and method for enabling bi-frequency dual-directional transfer of digitally encoded data on an RF carrier by translating between a crowded or otherwise undesirable first frequency band, such as the 2.4 GHz ISM band, and a less-crowded or otherwise desirable second frequency band, such as the 5.0 GHz-6.0 GHz U-NII band. In a preferred embodiment, the transverter (10) connects between an existing data radio (11) and its existing antenna (30), and comprises a bandswitch (12); an input RF isolating device (14); a transmuter (16); a converter (18); a dual output local oscillator (20); an output RF isolating device (22); and an antenna (24) tuned to the second frequency band. The bandswitch (12) allows for bypassing the transverter (10), thereby facilitating its use with legacy systems. The transmuter (14) and converter (16) are adapted to convert to and from, respectively, the second frequency band.

  16. Equivalent circuits for power system studies on the A-C network calculator 

    E-Print Network [OSTI]

    Kolb, Walter Jean

    1948-01-01

    EQUIVALENT CIRCUITS FOR POWER SYSTEM STUDIES ON THE A-C NETWORK CALCULATOR A Thesis By Walter Jean Kolb August 1948 Approved as to t e an content by Chairman oi omm tee EQUIVALENT CIRCUITS FOR POWER SYSTEM STUDIES ON TRE A-C NETWORK... CALCULATOR A Thesis By Walter Jean Kalb August 1948 EQUIVALENT CIRCUITS FOR POWER SYSTEM STUDIES ON TRE A-C NETWORK CALCULATOR A Thesis Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfi. lment...

  17. Segmented superconducting tape having reduced AC losses and method of making

    DOE Patents [OSTI]

    Foltyn, Stephen R. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Arendt, Paul N. (Los Alamos, NM); Holesinger, Terry G. (Los Alamos, NM); Wang, Haiyan (Los Alamos, NM)

    2009-09-22

    A superconducting tape having reduced AC losses. The tape has a high temperature superconductor layer that is segmented. Disruptive strips, formed in one of the tape substrate, a buffer layer, and the superconducting layer create parallel discontinuities in the superconducting layer that separate the current-carrying elements of the superconducting layer into strips or filament-like structures. Segmentation of the current-carrying elements has the effect of reducing AC current losses. Methods of making such a superconducting tape and reducing AC losses in such tapes are also disclosed.

  18. Graphene-coated coupling coil for AC resistance reduction

    DOE Patents [OSTI]

    Miller, John M

    2014-03-04

    At least one graphene layer is formed to laterally surround a tube so that the basal plane of each graphene layer is tangential to the local surface of the tube on which the graphene layer is formed. An electrically conductive path is provided around the tube for providing high conductivity electrical path provided by the basal plane of each graphene layer. The high conductivity path can be employed for high frequency applications such as coupling coils for wireless power transmission to overcome skin depth effects and proximity effects prevalent in high frequency alternating current paths.

  19. Wide-frequency range, dynamic matching network and power system for the “Shoelace” radio frequency antenna on the Alcator C-Mod tokamak

    SciTech Connect (OSTI)

    Golfinopoulos, Theodore, E-mail: golfit@mit.edu; LaBombard, Brian; Burke, William; Parker, Ronald R.; Parkin, William; Woskov, Paul [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139 (United States)] [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139 (United States)

    2014-04-15

    A wide-frequency range (50–300 kHz) power system has been implemented for use with a new RF antenna – the “Shoelace” antenna – built to drive coherent plasma fluctuations in the edge of the Alcator C-Mod tokamak. A custom, dynamically tunable matching network allows two commercial 1 kW, 50-? RF amplifiers to drive the low-impedance, inductive load presented by the antenna. This is accomplished by a discretely variable L-match network, with 81 independently selected steps available for each of the series and parallel legs of the matching configuration. A compact programmable logic device provides a control system that measures the frequency with better than 1 kHz accuracy and transitions to the correct tuning state in less than 1 ms. At least 85% of source power is dissipated in the antenna across the operational frequency range, with a minimum frequency slew rate of 1 MHz/s; the best performance is achieved in the narrower band from 80 to 150 kHz which is of interest in typical experiments. The RF frequency can be run with open-loop control, following a pre-programmed analog waveform, or phase-locked to track a plasma fluctuation diagnostic signal in real time with programmable phase delay; the amplitude control is always open-loop. The control waveforms and phase delay are programmed remotely. These tools have enabled first-of-a-kind measurements of the tokamak edge plasma system response in the frequency range and at the wave number at which coherent fluctuations regulate heat and particle transport through the plasma boundary.

  20. A Reexamination of Stimulus-Frequency Effects in Recognition: Two Mirrors for Low-and High-Frequency Pseudowords

    E-Print Network [OSTI]

    Reder, Lynne

    A Reexamination of Stimulus-Frequency Effects in Recognition: Two Mirrors for Low- and High-Frequency than for high-frequency words) has intrigued memory researchers, and multiple accounts have been judgments for presented items) is higher for low- frequency words than for high-frequency words (e

  1. Variability-aware system-level design and analysis

    E-Print Network [OSTI]

    Chandra, Saumya

    2009-01-01

    Voltage-Frequency Island Systems,” in Proc. Int. Conf.in multi-voltage island systems) have different frequency-

  2. Time-frequency analysis of Transitory/Permanent frequency decrease in civil engineering structures during earthquakes

    E-Print Network [OSTI]

    Michel, Clotaire

    2008-01-01

    The analysis of strong motion recordings in structures is crucial to understand the damaging process during earthquakes. A very precise time-frequency representation, the reassigned smoothed pseudo-Wigner-Ville method, allowed us to follow the variation of the Millikan Library (California) and the Grenoble City Hall building (France) resonance frequencies during earthquakes. Under strong motions, a quick frequency drop, attributed to damage of the soil-structure system, followed by a slower increase is found. However, in the case of weak earthquakes, we show that frequency variations come from the ground motion spectrum and cannot be interpreted in terms of change of the soil-structure system.

  3. Radio-frequency driven dipole-dipole interactions in spatially separated volumes

    E-Print Network [OSTI]

    Atreju Tauschinsky; C. S. E. van Ditzhuijzen; L. D. Noordam; H. B. van Linden van den Heuvell

    2008-10-14

    Radio-frequency (rf) fields in the MHz range are used to induce resonant energy transfer between cold Rydberg atoms in spatially separated volumes. After laser preparation of the Rydberg atoms, dipole-dipole coupling excites the 49s atoms in one cylinder to the 49p state while the 41d atoms in the second cylinder are transferred down to the 42p state. The energy exchanged between the atoms in this process is 33 GHz. An external rf-field brings this energy transfer into resonance. The strength of the interaction has been investigated as a function of amplitude (0-1 V/cm) and frequency (1-30 MHz) of the rf-field and as a function of a static field offset. Multi-photon transitions up to fifth order as well as selection rules prohibiting the process at certain fields have been observed. The width of the resonances has been reduced compared to earlier results by switching off external magnetic fields of the magneto-optical trap, making sub-MHz spectroscopy possible. All features are well reproduced by theoretical calculations taking the strong ac-Stark shift due to the rf-field into account.

  4. Analysis of core damage frequency: Peach Bottom, Unit 2 internal events appendices

    SciTech Connect (OSTI)

    Kolaczkowski, A.M.; Cramond, W.R.; Sype, T.T.; Maloney, K.J.; Wheeler, T.A.; Daniel, S.L.; Sandia National Labs., Albuquerque, NM )

    1989-08-01

    This document contains the appendices for the accident sequence analysis of internally initiated events for the Peach Bottom, Unit 2 Nuclear Power Plant. This is one of the five plant analyses conducted as part of the NUREG-1150 effort for the Nuclear Regulatory Commission. The work performed and described here is an extensive reanalysis of that published in October 1986 as NUREG/CR-4550, Volume 4. It addresses comments from numerous reviewers and significant changes to the plant systems and procedures made since the first report. The uncertainty analysis and presentation of results are also much improved, and considerable effort was expended on an improved analysis of loss of offsite power. The content and detail of this report is directed toward PRA practitioners who need to know how the work was done and the details for use in further studies. The mean core damage frequency is 4.5E-6 with 5% and 95% uncertainty bounds of 3.5E-7 and 1.3E-5, respectively. Station blackout type accidents (loss of all ac power) contributed about 46% of the core damage frequency with Anticipated Transient Without Scram (ATWS) accidents contributing another 42%. The numerical results are driven by loss of offsite power, transients with the power conversion system initially available operator errors, and mechanical failure to scram. 13 refs., 345 figs., 171 tabs.

  5. RADIO FREQUENCY PHASE IN THE FEL SECTION OF A TBA

    E-Print Network [OSTI]

    Kuenning, R.W.

    2008-01-01

    Amplitude Control of the Radio Frequency Wave in the Two-Madison, WI, August 21-27, 1986 RADIO FREQUENCY PHASE IN THEAC03-76SF00098 LBL- 223Pl RADIO FREQUENCY PHASE IN THE FEL

  6. Radar network communication through sensing of frequency hopping

    DOE Patents [OSTI]

    Dowla, Farid; Nekoogar, Faranak

    2013-05-28

    In one embodiment, a radar communication system includes a plurality of radars having a communication range and being capable of operating at a sensing frequency and a reporting frequency, wherein the reporting frequency is different than the sensing frequency, each radar is adapted for operating at the sensing frequency until an event is detected, each radar in the plurality of radars has an identification/location frequency for reporting information different from the sensing frequency, a first radar of the radars which senses the event sends a reporting frequency corresponding to its identification/location frequency when the event is detected, and all other radars in the plurality of radars switch their reporting frequencies to match the reporting frequency of the first radar upon detecting the reporting frequency switch of a radar within the communication range. In another embodiment, a method is presented for communicating information in a radar system.

  7. Ultra High Frequency Volatility Estimation with Dependent Microstructure Noise

    E-Print Network [OSTI]

    Ultra High Frequency Volatility Estimation with Dependent Microstructure Noise Yacine Aït sampled at frequencies high enough for that noise to be a dominant consideration. We show that combining; Serial dependence; High frequency data; Realized volatility; Sub- sampling; Two Scales Realized

  8. ORIGINAL PAPER Fire frequency and tree canopy structure influence plant

    E-Print Network [OSTI]

    Minnesota, University of

    composition (Huston 1994). Ecological theory predicts important linkages between disturbance frequency frequencies and severities that minimize species losses due to competitive exclusion and direct disturbanceORIGINAL PAPER Fire frequency and tree canopy structure influence plant species diversity

  9. High frequency inductive lamp and power oscillator

    DOE Patents [OSTI]

    MacLennan, Donald A. (Gaithersburg, MD); Turner, Brian P. (Damascus, MD); Dolan, James T. (Frederick, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Leng, Yongzhang (Damascus, MD)

    2000-01-01

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

  10. High frequency inductive lamp and power oscillator

    DOE Patents [OSTI]

    MacLennan, Donald A. (Gaithersburg, MD); Dymond, Jr., Lauren E. (North Potomac, MD); Gitsevich, Aleksandr (Montgomery Village, MD); Grimm, William G. (Silver Spring, MD); Kipling, Kent (Gaithersburg, MD); Kirkpatrick, Douglas A. (Great Falls, VA); Ola, Samuel A. (Silver Spring, MD); Simpson, James E. (Gaithersburg, MD); Trimble, William C. (Columbia, MD); Tsai, Peter (Olney, MD); Turner, Brian P. (Damascus, MD)

    2001-01-01

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to adjust the driving frequency of the oscillator.

  11. Variable-speed wind power system with improved energy capture via multilevel conversion

    DOE Patents [OSTI]

    Erickson, Robert W.; Al-Naseem, Osama A.; Fingersh, Lee Jay

    2005-05-31

    A system and method for efficiently capturing electrical energy from a variable-speed generator are disclosed. The system includes a matrix converter using full-bridge, multilevel switch cells, in which semiconductor devices are clamped to a known constant DC voltage of a capacitor. The multilevel matrix converter is capable of generating multilevel voltage wave waveform of arbitrary magnitude and frequencies. The matrix converter can be controlled by using space vector modulation.

  12. High frequency VLBI observations of the scatter broadened quasar B2005+403

    E-Print Network [OSTI]

    K. E. Gabanyi; T. P. Krichbaum; S. Britzen; U. Bach; E. Ros; A. Witzel; J. A. Zensus

    2006-01-17

    The quasar B2005+403 located behind the Cygnus region, is a suitable object for studying the interplay between propagation effects, which are extrinsic to the source and source intrinsic variability. On the basis of VLBI experiments performed at 1.6, 5, 8, 15, 22, and 43GHz between 1992-2003 and parallel multi-frequency monitoring of the total flux density, we investigated the variability of total flux density and source structure. Below 8 GHz, the point-like VLBI source is affected by scatter-broadening of the turbulent interstellar medium, which is located along the line of sight and likely associated with the Cygnus region. We present and discuss the measured frequency dependence of the source size, which shows a power-law with slope of -1.91+/-0.05. From the measured scattering angle at 1GHz of 77.1+/-4.0mas a SM=0.43+/-0.04 m^{-20/3} kpc is derived, consistent with the general properties of the ISM in this direction. The decreasing effect of angular broadening towards higher frequencies allows to study the internal structure of the source. Above 8GHz new VLBI observations reveal a one-sided slightly south-bending core-jet structure, with stationary and apparent superluminally moving jet components. The jet components move on non-ballistic trajectories. In AGN, total flux density variations are often related to the emergence of new VLBI components. However, during almost eleven years no new component was ejected in B2005+403. In the flux density variability a trough is observed at 5-37 GHz between 1996 and 2001. This can be explained as a blending effect of jet component fluxes. Dense in time sampled flux density monitoring observations reveal intra-day variability at 1.6GHz impling a second, less dense or turbulent scattering screen at few to hundred parsec distance.

  13. Variable path length spectrophotometric probe

    DOE Patents [OSTI]

    O'Rourke, Patrick E. (157 Greenwood Dr., Martiney, GA 30907); McCarty, Jerry E. (104 Recreation Dr., Aiken, SC 29803); Haggard, Ricky A. (1144 Thornwood Drive, North Augusta, SC 29891)

    1992-01-01

    A compact, variable pathlength, fiber optic probe for spectrophotometric measurements of fluids in situ. The probe comprises a probe body with a shaft having a polished end penetrating one side of the probe, a pair of optic fibers, parallel and coterminous, entering the probe opposite the reflecting shaft, and a collimating lens to direct light from one of the fibers to the reflecting surface of the shaft and to direct the reflected light to the second optic fiber. The probe body has an inlet and an outlet port to allow the liquid to enter the probe body and pass between the lens and the reflecting surface of the shaft. A linear stepper motor is connected to the shaft to cause the shaft to advance toward or away from the lens in increments so that absorption measurements can be made at each of the incremental steps. The shaft is sealed to the probe body by a bellows seal to allow freedom of movement of the shaft and yet avoid leakage from the interior of the probe.

  14. Abstract--The analysis of heart rate variability (HRV) signals is an important tool for studying the autonomic nervous

    E-Print Network [OSTI]

    Carvalho, João Luiz

    Abstract-- The analysis of heart rate variability (HRV) signals is an important tool for studying and parasympathetic influences on heart rhythm. Time-frequency analysis of HRV makes it easier to evaluate how (HRV) developed in Matlab 6.5 Three techniques are available: Short- Time Fourier Transform, Continuous

  15. Eccentric crank variable compression ratio mechanism

    DOE Patents [OSTI]

    Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)

    2008-05-13

    A variable compression ratio mechanism for an internal combustion engine that has an engine block and a crankshaft is disclosed. The variable compression ratio mechanism has a plurality of eccentric disks configured to support the crankshaft. Each of the plurality of eccentric disks has at least one cylindrical portion annularly surrounded by the engine block. The variable compression ratio mechanism also has at least one actuator configured to rotate the plurality of eccentric disks.

  16. Dynamic frequency tuning of electric and magnetic metamaterial...

    Office of Scientific and Technical Information (OSTI)

    can achieve active optical andor electronic control of the frequency response in metamaterials andor frequency selective surfaces, potentially with sub-picosecond response...

  17. EA-1631: Beacon Power Corporation Frequency Regulation Facility...

    Office of Environmental Management (EM)

    1: Beacon Power Corporation Frequency Regulation Facility in Stephentown, NY EA-1631: Beacon Power Corporation Frequency Regulation Facility in Stephentown, NY February 2, 2009...

  18. Microwave (MW) and Radio Frequency (RF) as Enabling Technologies...

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

    Microwave (MW) and Radio Frequency (RF) as Enabling Technologies for Advanced Manufacturing Microwave (MW) and Radio Frequency (RF) as Enabling Technologies for Advanced...

  19. Integration of Full Tensor Gravity and ZTEM Passive Low Frequency...

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

    Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments...

  20. Frequency dispersion of nonlinear response of thin superconducting...

    Office of Scientific and Technical Information (OSTI)

    of the films reproduce well the low frequency behavior, but fail above cut. Thus, high-frequency radiation is much less effective in inducing vortex-antivortex dissociation...

  1. Radio Frequency Diesel Particulate Filter Sensor Reduces Fuel...

    Office of Environmental Management (EM)

    Radio Frequency Diesel Particulate Filter Sensor Reduces Fuel Consumption, Wins R&D 100 Award Radio Frequency Diesel Particulate Filter Sensor Reduces Fuel Consumption, Wins R&D...

  2. Climate dynamics and fluid mechanics: Natural variability and related uncertainties

    E-Print Network [OSTI]

    Michael Ghil; Mickaël D. Chekroun; Eric Simonnet

    2010-06-15

    The purpose of this review-and-research paper is twofold: (i) to review the role played in climate dynamics by fluid-dynamical models; and (ii) to contribute to the understanding and reduction of the uncertainties in future climate-change projections. To illustrate the first point, we focus on the large-scale, wind-driven flow of the mid-latitude oceans which contribute in a crucial way to Earth's climate, and to changes therein. We study the low-frequency variability (LFV) of the wind-driven, double-gyre circulation in mid-latitude ocean basins, via the bifurcation sequence that leads from steady states through periodic solutions and on to the chaotic, irregular flows documented in the observations. This sequence involves local, pitchfork and Hopf bifurcations, as well as global, homoclinic ones. The natural climate variability induced by the LFV of the ocean circulation is but one of the causes of uncertainties in climate projections. Another major cause of such uncertainties could reside in the structural instability in the topological sense, of the equations governing climate dynamics, including but not restricted to those of atmospheric and ocean dynamics. We propose a novel approach to understand, and possibly reduce, these uncertainties, based on the concepts and methods of random dynamical systems theory. As a very first step, we study the effect of noise on the topological classes of the Arnol'd family of circle maps, a paradigmatic model of frequency locking as occurring in the nonlinear interactions between the El Nino-Southern Oscillations (ENSO) and the seasonal cycle. It is shown that the maps' fine-grained resonant landscape is smoothed by the noise, thus permitting their coarse-grained classification. This result is consistent with stabilizing effects of stochastic parametrization obtained in modeling of ENSO phenomenon via some general circulation models.

  3. Audio-band frequency-dependent squeezing

    E-Print Network [OSTI]

    Oelker, Eric; Miller, John; Tse, Maggie; Barsotti, Lisa; Mavalvala, Nergis; Evans, Matthew

    2015-01-01

    Quantum vacuum fluctuations impose strict limits on precision displacement measurements, those of interferometric gravitational-wave detectors among them. Introducing squeezed states into an interferometer's readout port can improve the sensitivity of the instrument, leading to richer astrophysical observations. However, optomechanical interactions dictate that the vacuum's squeezed quadrature must rotate by 90 degrees around 50Hz. Here we use a 2-m-long, high-finesse optical resonator to produce frequency-dependent rotation around 1.2kHz. This demonstration of audio-band frequency-dependent squeezing uses technology and methods that are scalable to the required rotation frequency, heralding application of the technique in future gravitational-wave detectors.

  4. Pioneering research from the University of Cambridge www.cam.ac.uk/research

    E-Print Network [OSTI]

    .cam.ac.uk/research Feature Mapping the Milky Way in 3D Feature Europe's 2030 challenges Spotlight Migration #12;Contents A 4 ­ 35 ExtremesleepoverintheKalahari Inside out D Editor DrLouiseWalsh Design TheDistrict Printers

  5. AC losses in type-II superconductors induced by nonuniform fluctuations of external magnetic field

    E-Print Network [OSTI]

    as the economic gains of implementation of type-II superconductors in power transmission lines, current leads amplitude. The results can be used to estimate the AC losses in flywheels, electric motors, magnetic shields

  6. Lift-and-Project Relaxations of AC Microgrid Distribution System Planning

    E-Print Network [OSTI]

    Taylor, Joshua A.

    2011-01-01

    We apply relaxation procedures to polynomial optimization problems that originate in transmission system planning, and obtain new convex formulations for the AC case. The approach is novel because the optimization is ...

  7. Contract Number: DE-AC05-76RL01830 Modification M412

    E-Print Network [OSTI]

    Health Services H-22 Lobbying Restriction (Energy & Water Development Appropriations Act, 2003) (AL- 2003-03) #12;Contract Number: DE-AC05-76RL01830 Modification M412 H-13 Care Of Laboratory Animals H-14

  8. ac field enhanced protein crystallization Diana Hou and Hsueh-Chia Changa

    E-Print Network [OSTI]

    Chang, Hsueh-Chia

    ac field enhanced protein crystallization Diana Hou and Hsueh-Chia Changa Chemical and Biomolecular is estimated to be a low 10-6 cm2 /s.5 Ex- isting methods such as vapor diffusion, seeding, microfluid- ics

  9. MIT Electric Vehicle Team Porsche designing a cooling system for the AC24 electric motor

    E-Print Network [OSTI]

    Meenen, Jordan N

    2010-01-01

    In this thesis I worked on the design and analysis of a cooling system for the electric motor of the MIT Electric Vehicle Team's Porsche 914 Battery Electric Vehicle. The vehicle's Azure Dynamics AC24 motor tended to ...

  10. AEP (Central and SWEPCO)- Coolsaver A/C Tune Up or Replacement

    Broader source: Energy.gov [DOE]

    Participating customers are eligible to receive a $75 coupon for use toward A/C and heat pump efficiency services performed as a result of the program’s tune-up analysis, contractors are eligible...

  11. Ultrafast High-pressure AC Electro-osmotic Pumps for Portable Biomedical Microfluidics

    E-Print Network [OSTI]

    Huang, Chien-Chih

    This paper details the development of an integrated AC electro-osmotic (ACEO) microfluidic pump for dilute electrolytes consisting of a long serpentine microchannel lined with three dimensional (3D) stepped electrode arrays. ...

  12. Docket No. EERE-2012-BT-TP-0046; RIN 1904-AC52 Ex partecommunication...

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

    Ex parte communication Meeting of May 16, 2013 Docket No. EERE-2012-BT-TP-0046; RIN 1904-AC52 Ex parte communication Meeting of May 16, 2013 This memorandum for the record...

  13. Update 9: October 2014 www.canterbury.ac.nz UC Stakeholder Update

    E-Print Network [OSTI]

    Hickman, Mark

    Update 9: October 2014 www.canterbury.ac.nz UC Stakeholder Update October 2014 UC leases Old will pump added energy through the cultural heart of Christchurch," Dr Carr says. "This demonstrates

  14. ACS symposium on theory of electrochemical interfaces Stuctural and Dynamic Properties of Hexadecane Lubricants Under

    E-Print Network [OSTI]

    Çagin, Tahir

    4/3/00 ACS symposium on theory of electrochemical interfaces Stuctural and Dynamic Properties in designing engine surfaces with reduced engine wear. 5;6;7 The model of the present study builds upon our

  15. A Partitioning Approach for Parallel Simulation of AC-Radial Shipboard Power Systems 

    E-Print Network [OSTI]

    Uriarte, Fabian Marcel

    2011-08-08

    An approach to parallelize the simulation of AC-Radial Shipboard Power Systems (SPSs) using multicore computers is presented. Time domain simulations of SPSs are notoriously slow, due principally to the number of components, ...

  16. Department of Physics, Durham UK www.durham.ac.uk/cmp

    E-Print Network [OSTI]

    Hampshire, Damian

    and Heat-Treatment ASC 2012, Portland, OR Laboratory power supplies are supported by a back-up generator to ensure uninterrupted heat-treatments #12;Centre for Materials Physics www.durham.ac.uk/cmp 9Furnaces

  17. System and Battery Charge Control for PV-Powered AC Lighting Systems

    SciTech Connect (OSTI)

    Kern, G.

    1999-04-01

    This report reviews a number of issues specific to stand-alone AC lighting systems. A review of AC lighting technology is presented, which discusses the advantages and disadvantages of various lamps. The best lamps for small lighting systems are compact fluorescent. The best lamps for intermediate-size systems are high- or low-pressure sodium. Specifications for battery charging and load control are provided with the goal of achieving lamp lifetimes on the order of 16,000 to 24,000 hours and battery lifetimes of 4 to 5 years. A rough estimate of the potential domestic and global markets for stand-alone AC lighting systems is presented. DC current injection tests were performed on high-pressure sodium lamps and the test results are presented. Finally, a prototype system was designed and a prototype system controller (with battery charger and DC/AC inverter) was developed and built.

  18. Variable-Period Undulators For Synchrotron Radiation

    DOE Patents [OSTI]

    Shenoy, Gopal (Naperville, IL); Lewellen, John (Plainfield, IL); Shu, Deming (Darien, IL); Vinokurov, Nikolai (Novosibirsk, RU)

    2005-02-22

    A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high-energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

  19. Effect on the condition of the metal in A K-300-3.5 turbine owing to multicycle fatigue from participation of a power generating unit in grid frequency and power regulation

    SciTech Connect (OSTI)

    Lebedeva, A. I.; Zorchenko, N. V.; Prudnikov, A. A.

    2011-09-15

    The effect on the condition of the rotor material owing to multicycle fatigue caused by variable stresses during participation of a power generating unit in grid frequency and power regulation is evaluated using the K-300-23.5 steam turbine as an example. It is shown that during normalized primary frequency regulation the safety factor is at least 50, while during automatic secondary regulation of frequency and power there is essentially no damage to the metal.

  20. Electrojet-independent ionospheric extremely low frequency/very low frequency wave generation by powerful high frequency waves

    SciTech Connect (OSTI)

    Kuo, Spencer; Snyder, Arnold; Chang, Chia-Lie

    2010-08-15

    Results of extremely low frequency/very low frequency (ELF/VLF) wave generation by intensity-modulated high frequency (HF) heaters of 3.2 MHz in Gakona, Alaska, near local solar noon during a geomagnetic quiet time, are presented to support an electrojet-independent ELF/VLF wave generation mechanism. The modulation was set by splitting the HF transmitter array into two subarrays; one was run at cw full power and the other run alternatively at 50% and 100% power modulation by rectangular waves of 2.02, 5, 8, and 13 kHz. The most effective generation was from the X-mode heater with 100% modulation. While the 8 kHz radiation has the largest wave amplitude, the spectral intensity of the radiation increases with the modulation frequency, i.e., 13 kHz line is the strongest. Ionograms recorded significant virtual height spread of the O-mode sounding echoes. The patterns of the spreads and the changes of the second and third hop virtual height traces caused by the O/X-mode heaters are distinctively different, evidencing that it is due to differently polarized density irregularities generated by the filamentation instability of the O/X-mode HF heaters.

  1. Computing Instantaneous Frequency by normalizing Hilbert Transform

    DOE Patents [OSTI]

    Huang, Norden E.

    2005-05-31

    This invention presents Normalized Amplitude Hilbert Transform (NAHT) and Normalized Hilbert Transform(NHT), both of which are new methods for computing Instantaneous Frequency. This method is designed specifically to circumvent the limitation set by the Bedorsian and Nuttal Theorems, and to provide a sharp local measure of error when the quadrature and the Hilbert Transform do not agree. Motivation for this method is that straightforward application of the Hilbert Transform followed by taking the derivative of the phase-angle as the Instantaneous Frequency (IF) leads to a common mistake made up to this date. In order to make the Hilbert Transform method work, the data has to obey certain restrictions.

  2. Seismic isolation systems with distinct multiple frequencies

    DOE Patents [OSTI]

    Wu, Ting-shu (Downers Grove, IL); Seidensticker, Ralph W. (Wheaton, IL)

    1990-01-01

    A method and apparatus for isolating a building or other structure from smic vibratory motion which provides increased assurance that large horizontal motion of the structure will not occur than is provided by other isolation systems. Increased assurance that large horizontal motion will not occur is achieved by providing for change of the natural frequency of the support and structure system in response to displacement of the structure beyond a predetermined value. The natural frequency of the support and structure system may be achieved by providing for engaging and disengaging of the structure and some supporting members in response to motion of the supported structure.

  3. www.ccfe.ac.uk CPS13.486 (August 2013)

    E-Print Network [OSTI]

    www.ccfe.ac.uk CPS13.486 (August 2013) InFusion Issue 04 | Summer 2013 The work at CCFE is funded by the RCUK Energy Programme and EURATOM Issue 04 |Summer 2013 www.ccfe.ac.uk InFusion CCFE Show and Tell visit to site power supplies Changing times for MAST #12;InFusion Issue 04 | Summer 2013 In this issue

  4. www.ccfe.ac.uk CPS13.1239 (March 2014)

    E-Print Network [OSTI]

    www.ccfe.ac.uk CPS13.1239 (March 2014) InFusion Issue 05 | Spring 2014 The work at CCFE is funded by the RCUK Energy Programme and EURATOM Issue 05 |Spring 2014 www.ccfe.ac.uk InFusion Themakingoffusion's see if it behaves hoW we expect... #12;InFusion Issue 05 | Spring 2014 In this issue 04 The story

  5. 2015.07-[] OKhttp://www.dl.itc.u-tokyo.ac.jp/gacos/index.html

    E-Print Network [OSTI]

    Goda, Keisuke

    Works http://www.dl.itc.u-tokyo.ac.jp/gacos/faq/refw.html TREE CiNii Articles Web of Science OPAC #122015.07- [] 1 OKhttp://www.dl.itc.u-tokyo.ac.jp/gacos/index.html TREE TREE p.3 MyOPAC TREE p.5 DOI p.6 OPAC TREE p.7 E-JOURNAL PORTAL p.9 CiNii Articles p.10-11 Web of Science

  6. Envera Variable Compression Ratio Engine

    SciTech Connect (OSTI)

    Charles Mendler

    2011-03-15

    Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new technologies are packaged together to provide the greatest gains at the least cost. Aggressive engine downsiz

  7. Distributed Frequency-Preserving Optimal Load Control

    E-Print Network [OSTI]

    Wierman, Adam

    Distributed Frequency-Preserving Optimal Load Control Enrique Mallada Steven H. Low California prices to incentivize the users to adapt their consumption to the true cost of generation at the time to accept more readily a stochastically fluctuating energy source, such as wind or solar generation

  8. Time-Frequency Analysis as Probabilistic Inference

    E-Print Network [OSTI]

    Turner, Richard E.

    2014-11-06

    ) and (19) yields: (21) 6176 IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 62, NO. 23, DECEMBER 1, 2014 Fig. 1. Relationships between classical and probabilistic time-frequency anal- ysis. A complex filter bank (cFB, ) is formed from a set of filters...

  9. Distributed vs. Centralized Power Systems Frequency Control

    E-Print Network [OSTI]

    Dimarogonas, Dimos

    Distributed vs. Centralized Power Systems Frequency Control Martin Andreasson12 , Dimos V control of electrical power systems. We propose a distributed controller which retains the reference, where their performance is compared. I. INTRODUCTION Distributed control is in many large-scale systems

  10. Oscillator Architectures and Enhanced Frequency Synthesizer 

    E-Print Network [OSTI]

    Park, Sang Wook

    2009-11-16

    A voltage controlled oscillator (VCO), that generates a periodic signal whose frequency is tuned by a voltage, is a key building block in any integrated circuit systems. A sine wave oscillator can be used for a built-in self testing where high...

  11. Plasmonics in graphene at infrared frequencies

    SciTech Connect (OSTI)

    Jablan, Marinko; Buljan, Hrvoje; Soljacic, Marin

    2009-12-23

    We point out that plasmons in doped graphene simultaneously enable low losses and significant wave localization for frequencies below that of the optical phonon branch ??Oph ?0.2 eV . Large plasmon losses occur in the interband regime (via excitation of electron-hole pairs), which can be pushed toward higher frequencies for higher-doping values. For sufficiently large dopings, there is a bandwidth of frequencies from ?Oph up to the interband threshold, where a plasmon decay channel via emission of an optical phonon together with an electron-hole pair is nonegligible. The calculation of losses is performed within the framework of a random-phase approximation and number conserving relaxation-time approximation. The measured DC relaxation-time serves as an input parameter characterizing collisions with impurities, whereas the contribution from optical phonons is estimated from the influence of the electron-phonon coupling on the optical conductivity. Optical properties of plasmons in graphene are in many relevant aspects similar to optical properties of surface plasmons propagating on dielectric-metal interface, which have been drawing a lot of interest lately because of their importance for nanophotonics. Therefore, the fact that plasmons in graphene could have low losses for certain frequencies makes them potentially interesting for nanophotonic applications.

  12. The ACS Survey of Galactic Globular Clusters. VII. Relative Ages

    E-Print Network [OSTI]

    Marin-Franch, Antonio; Piotto, Giampaolo; Rosenberg, Alfred; Chaboyer, Brian; Sarajedini, Ata; Siegel, Michael; Anderson, Jay; Bedin, Luigi R; Dotter, Aaron; Hempel, Maren; King, Ivan; Majewski, Steven; Milone, Antonino P; Paust, Nathaniel; Reid, I Neill

    2008-01-01

    The ACS Survey of Galactic Globular Clusters is a Hubble Space Telescope (HST) Treasury program designed to provide a new large, deep and homogeneous photometric database. Based on observations from this program, we have measured precise relative ages for a sample of 64 Galactic globular clusters by comparing the relative position of the clusters' main sequence turn offs, using main-sequence fitting to cross-compare clusters within the sample. This method provides relative ages to a formal precision of 2-7%. We demonstrate that the calculated relative ages are independent of the choice of theoretical model. We find that the Galactic globular cluster sample can be divided into two groups -- a population of old clusters with an age dispersion of ~5% and no age-metallicity relation, and a group of younger clusters with an age-metallicity relation similar to that of the globular clusters associated with the Sagittarius dwarf galaxy. These results are consistent with the Milky Way halo having formed in two phases ...

  13. The Taiwanese-American occultation survey project stellar variability. III. Detection of 58 new variable stars

    SciTech Connect (OSTI)

    Ishioka, R.; Wang, S.-Y.; Zhang, Z.-W.; Lehner, M. J.; Cook, K. H.; King, S.-K.; Lee, T.; Marshall, S. L.; Schwamb, M. E.; Wang, J.-H.; Wen, C.-Y.; Alcock, C.; Protopapas, P.; Axelrod, T.; Bianco, F. B.; Byun, Y.-I.; Chen, W. P.; Ngeow, C.-C.; Kim, D.-W.; Rice, J. A.

    2014-04-01

    The Taiwanese-American Occultation Survey project is designed for the detection of stellar occultations by small-size Kuiper Belt Objects, and it has monitored selected fields along the ecliptic plane by using four telescopes with a 3 deg{sup 2} field of view on the sky since 2005. We have analyzed data accumulated during 2005-2012 to detect variable stars. Sixteen fields with observations of more than 100 epochs were examined. We recovered 85 variables among a total of 158 known variable stars in these 16 fields. Most of the unrecovered variables are located in the fields observed less frequently. We also detected 58 variable stars which are not listed in the International Variable Star Index of the American Association of Variable Star Observers. These variable stars are classified as 3 RR Lyrae, 4 Cepheid, 1 ? Scuti, 5 Mira, 15 semi-regular, and 27 eclipsing binaries based on the periodicity and the profile of the light curves.

  14. Search for Variable Stars in the WTS

    E-Print Network [OSTI]

    Pinfield, David J.

    Search for Variable Stars in the WTS Database Hristo Stoev Laboratory of Stellar Astrophysics of January 2010 at LAEX in Madrid, Spain #12;WTS Survey Release 0.1 Search for variable stars in the FOV Narrow down my selection only to one of the detectors ­ 15000 light curves #12;WTS Survey Release 0

  15. Variable orifice using an iris shutter

    DOE Patents [OSTI]

    Beeman, Raymond (El Cerrito, CA); Brajkovich, Steven J. (Fremont, CA)

    1978-01-01

    A variable orifice forming mechanism utilizing an iris shutter arrangement adapted to control gas flow, conductance in vacuum systems, as a heat shield for furnace windows, as a beam shutter in sputtering operations, and in any other application requiring periodic or continuously-variable control of material, gas, or fluid flow.

  16. Boosting Search with Variable Elimination. ? Javier Larrosa

    E-Print Network [OSTI]

    Dechter, Rina

    Boosting Search with Variable Elimination. ? Javier Larrosa Dep. Llenguatges i Sistemes Inform#12ElimSearchS;k, a hybrid meta- algorithm that combines search and variable elimination. The param- eter S names from the constraint graph. We also provide experimental evidence that the hybrid algorithm can

  17. Boosting Search with Variable Elimination. ? Javier Larrosa

    E-Print Network [OSTI]

    Dechter, Rina

    Boosting Search with Variable Elimination. ? Javier Larrosa Dep. Llenguatges i Sistemes Inform of variables, reduces the search tree size. In this paper we introduce VarElimSearch(S;k), a hybrid meta the constraint graph. We also provide experimental evidence that the hybrid algorithm can outperform state

  18. Solar Dynamics Observatory/ Extreme Ultraviolet Variability Experiment

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Solar Dynamics Observatory/ EVE Extreme Ultraviolet Variability Experiment Frequently Asked and model solar extreme ultraviolet irradiance variations due to solar flares, solar rotation, and solar and structure of the Sun. What is solar variability? Solar radiation varies on all time scales ranging from

  19. Property Variability Stochastic Multiscale Analysis and Design

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    Property Variability Stochastic Multiscale Analysis and Design of Engine Disks N. Zabaras, B. Wen in nickel-based superalloy turbine disks. Issues: Property variability of turbine disk due to high-dimensional multiscale sources Rolls-Royce RB211- 535 turbofan Nickel-base superalloy turbine disk Superalloy

  20. WIND VARIABILITY IN BZ CAMELOPARDALIS

    SciTech Connect (OSTI)

    Honeycutt, R. K.; Kafka, S.; Robertson, J. W. E-mail: skafka@dtm.ciw.edu

    2013-02-01

    Sequences of spectra of the nova-like cataclysmic variable (CV) BZ Cam were acquired on nine nights in 2005-2006 in order to study the time development of episodes of wind activity known to occur frequently in this star. We confirm the results of Ringwald and Naylor that the P-Cygni absorption components of the lines mostly evolve from higher expansion velocity to lower velocity as an episode progresses. We also commonly find blueshifted emission components in the H{alpha} line profile, whose velocities and durations strongly suggest that they are also due to the wind. Curiously, Ringwald and Naylor reported common occurrences of redshifted H{alpha} emission components in their BZ Cam spectra. We have attributed these emission components in H{alpha} to occasions when gas concentrations in the bipolar wind (both front side and back side) become manifested as emission lines as they move beyond the disk's outer edge. We also suggest, based on changes in the P-Cygni profiles during an episode, that the progression from larger to smaller expansion velocities is due to the higher velocity portions of a wind concentration moving beyond the edge of the continuum light of the disk first, leaving a net redward shift of the remaining absorption profile. We derive a new orbital ephemeris for BZ Cam, using the radial velocity of the core of the He I {lambda}5876 line, finding P = 0.15353(4). Using this period, the wind episodes in BZ Cam are found to be concentrated near the inferior conjunction of the emission line source. This result helps confirm that the winds in nova-like CVs are often phase dependent, in spite of the puzzling implication that such winds lack axisymmetry. We argue that the radiation-driven wind in BZ Cam receives an initial boost by acting on gas that has been lifted above the disk by the interaction of the accretion stream with the disk, thereby imposing flickering timescales onto the wind events, as well as leading to an orbital modulation of the wind due to the non-axisymmetric nature of the stream/disk interaction. Simultaneous photometry and spectroscopy were acquired on three nights in order to test the possible connection between flickering continuum light and the strength of the front-side wind. We found strong agreement on one night, some agreement on another, and no agreement on the third. We suggest that some flickering events lead to only back-side winds which will not have associated P-Cygni profiles.