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Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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1

Variable Frequency AC Drives for Cooling Tower Energy Efficiency  

E-Print Network [OSTI]

speed fan drives. Fan speed is reduced to yield specific water temperatures at thermal conditions less difficult than design. The reduced air flow is accomplished by reduced fan power consumption, resulting in optimum cooling tower operation... and economics. Automatic fan speed control by sensing cold water temperature is the economic essence of the application of adjustable frequency power to A-C fan motors. 2.2 Cell Partitions In some multi-cell mechanical-draft cooling towers, the isolation...

Corey, R. W.

1982-01-01T23:59:59.000Z

2

Variable Frequency Pump Drives  

E-Print Network [OSTI]

-frequency electric motor drive. What is happenin9 with variable frequency driven pun,ps is a classical illustration that evolution in technical products takes place not only because of changes in the processes served by these products, or because of innovations...-pole 3550 rpm squirrel caqe induction motor became available in the early 1930s that high pressure pumps operating at that speed could be buil t. And now, in the 1980s, the development of the solid-state, variable frequency electric motor drive...

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

3

Conservation Theory Process Control Using Variable Frequency Drives  

E-Print Network [OSTI]

name from the vari able DC voltage which the rectifier section pro duces. Variable DC voltage is required in order to produce controlled AC with the volts per hz ratio constant. To operate an AC motor over a speed range from 5-60 hz and still... be capable of producing con stant torque,the ratio: Volts ~ = Constant must be satisfied. The rectifier and inverter stages work in concert to produce variable voltage, variable frequency AC power. The linear relation ship between voltage and frequency...

Myers, N. S.

1980-01-01T23:59:59.000Z

4

High frequency AC power converter for low voltage circuits  

E-Print Network [OSTI]

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 ...

Salazar, Nathaniel Jay Tobias

2012-01-01T23:59:59.000Z

5

Variable frequency microwave heating apparatus  

DOE Patents [OSTI]

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).

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

1999-01-01T23:59:59.000Z

6

Variable frequency microwave furnace system  

DOE Patents [OSTI]

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).

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

1994-01-01T23:59:59.000Z

7

Variable frequency microwave furnace system  

DOE Patents [OSTI]

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.

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

1994-06-14T23:59:59.000Z

8

Application of multi-variable control for automatic frequency controller of HVDC transmission system  

SciTech Connect (OSTI)

In an HVDC transmission system that links two ac power systems, the automatic frequency controller (AFC) calculates power to be interchanged between the two ac systems according to their frequencies thereby improving the frequency characteristics of the two power systems. This paper introduces a newly developed dc AFC system, which applies a multi-variable control to the dc system-based frequency control. It is capable of controlling the frequencies of the two ac systems optimally while maintaining their stability. This system was developed for one of Japan's HVDC transmission facilities and produced good results in a combined test using a power system simulator. The field installation will be completed in March 1993, when the AFC system will enter service.

Sanpei, Masatoshi (Electric Power Development Co., Tokyo (Japan)); Kakehi, Atsuyuki; Takeda, Hideo (Toshiba Corp., Tokyo (Japan))

1994-04-01T23:59:59.000Z

9

Adhesive bonding using variable frequency microwave energy  

DOE Patents [OSTI]

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.

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)

1998-01-01T23:59:59.000Z

10

Adhesive bonding using variable frequency microwave energy  

DOE Patents [OSTI]

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.

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

1998-09-08T23:59:59.000Z

11

Adhesive bonding using variable frequency microwave energy  

DOE Patents [OSTI]

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.

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

1998-08-25T23:59:59.000Z

12

Chapter 18: Variable Frequency Drive Evaluation Protocol  

SciTech Connect (OSTI)

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.

Romberger, J.

2014-11-01T23:59:59.000Z

13

NEW ASPECTS OF SOME SMALL-SIGNAL ac FREQUENCY RESPONSE FUNCTIONS J. Ross MACDONALD  

E-Print Network [OSTI]

NEW ASPECTS OF SOME SMALL-SIGNAL ac FREQUENCY RESPONSE FUNCTIONS J. Ross MACDONALD Department. It was shown by Macdonald and Cook [5] that an admittance closely related to eq. (1) with n 1 = 0 and n 2 = n]. This analysis showed that #12;160 J. Ross Macdonald/Small-signal ac frequency response functions the data did

Macdonald, James Ross

14

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

DOE Patents [OSTI]

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.

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

1987-07-30T23:59:59.000Z

15

Present and Future Modes of Low Frequency Climate Variability  

SciTech Connect (OSTI)

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.

Cane, Mark A.

2014-02-20T23:59:59.000Z

16

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

E-Print Network [OSTI]

Variable frequency motor drives (VFD's) have been on the market for many years. Early versions were unreliable and prone to failure. Relatively recent developments in Pulse-Width Modulated (PWM) waveform technology have improved VFD reliability...

Massey, G. W.

17

The probable source of certain spurious frequencies found in the output of a variable speed generating system using slip recovery  

SciTech Connect (OSTI)

As part of US Department of Energy-sponsored research on wind energy, a Mod-O wind turbine was used to drive a variable-speed, wound-rotor, induction generator. Energy resulting from the slip frequency voltage in the generator rotor was rectified to dc, inverted back to utility frequency ac, and injected into the power line. Spurious changing frequencies displayed in the generator output by a spectrum analyzer are caused by ripple on the dc link. No resonances of any of these moving frequencies were seen in spite of the presence of a bank of power factor correcting capacitors. 5 figs.

Carlin, P.W.

1989-06-01T23:59:59.000Z

18

AC Resonant charger with charge rate unrelated to primary power frequency  

DOE Patents [OSTI]

An AC resonant charger for a capacitive load, such as a PFN, is provided with a variable repetition rate unrelated to the frequency of a multi-phase AC power source by using a control unit to select and couple the phase of the power source to the resonant charger in order to charge the capacitive load with a phase that is the next to begin a half cycle. For optimum range in repetition rate and increased charging voltage, the resonant charger includes a step-up transformer and full-wave rectifier. The next phase selected may then be of either polarity, but is always selected to be of a polarity opposite the polarity of the last phase selected so that the transformer core does not saturate. Thyristors are used to select and couple the correct phase just after its zero crossover in response to a sharp pulse generated by a zero-crossover detector. The thyristor that is turned on then automatically turns off after a full half cycle of its associated phase input. A full-wave rectifier couples the secondary winding of the transformer to the load so that the load capacitance is always charged with the same polarity.

Watson, Harold (Torrance, CA)

1982-01-01T23:59:59.000Z

19

Trapping and Frequency Variability in Electron Acoustic Waves  

E-Print Network [OSTI]

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 Langmuir waves, and at large excitations resonance is observed over a broad range. Laser Induced

California at San Diego, University of

20

Method for curing polymers using variable-frequency microwave heating  

DOE Patents [OSTI]

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.

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

1998-02-24T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Method for curing polymers using variable-frequency microwave heating  

DOE Patents [OSTI]

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.

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

1998-01-01T23:59:59.000Z

22

The ACS LCID Project: Variable Stars in Tucana and LGS3  

E-Print Network [OSTI]

We present preliminary results concerning the search for short-period variable stars in Tucana and LGS3 based on very deep HST/ACS imaging. In the one chip per galaxy we studied so far, a total of 230 and 80 candidates variables were found, respectively. For Tucana, we identified 134 of them as RR Lyrae stars (RRL) pulsating in the fundamental mode (RRab), 51 in the first-overtone mode (RRc), and 37 in both modes simultaneoulsy (RRd), as well as four candidate anomalous Cepheids (AC). In the case of LGS3, we found 45 RRab and 5 RRc, plus three candidates RRd and five candidate AC. The metallicities obtained from the mean period of the RRab are [Fe/H]_{Tuc}=-1.7 and [Fe/H]_{LGS3}=-1.8.

Edouard J. Bernard

2007-05-18T23:59:59.000Z

23

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

E-Print Network [OSTI]

STFC Introductory Summer School m.j.owens@reading.ac.uk18 Sept 2012 Solar Variability and Climate · The climate system · Solar variability · Solar effects on climate ­ Regional and global effects · The future? #12;STFC Introductory Summer School m.j.owens@reading.ac.uk Climate system #12;The source of much

24

Payback enormous for variable-frequency motor drives  

SciTech Connect (OSTI)

The City Utilities of Springfield's (Mo) 200-MW Southwest power station is a 200-MW plant anchored around a single coal-fired steam generator and its major support systems, including an electrostatic precipitator (ESP) and two wet limestone scrubbers. In the late 1980s, engineers at Southwest began evaluating the feasibility of installing variable-frequency drives (VFD) to reduce the plant's parasitic load and boost overall performance. This article reports on VFDs installed to control the induced draft (i-d) and forced-draft (f-d) fan motors at the plant. The devices have surpassed the utility's expectations by reducing parasitic load, improving combustion control, and increasing overall plant reliability. Virtually every major plant component--including the ESPs and scrubbers--performs better as a result of the retrofit.

Collins, S.

1993-02-01T23:59:59.000Z

25

THE SELF-ADJUSTING CURRENT-FED PUSH-PULL PARALLEL RESONANT INVERTER AS A HIGH FREQUENCY AC BUS DRIVER  

E-Print Network [OSTI]

. The power inverter is based on a Current-Fed Push-Pull Parallel-Resonant Inverter (CFPPRI), which includes power eliminates some of the conversion units, it poses new design challenges [1]: (a) ElectromagneticTHE SELF-ADJUSTING CURRENT-FED PUSH-PULL PARALLEL RESONANT INVERTER AS A HIGH FREQUENCY AC BUS

26

A very high frequency CMOS Variable Gain Amplifier  

E-Print Network [OSTI]

of the VGA output signal . . . . . . . . . 80 Bandwidth with different frequency compensation circuits bias current at 22dB gain setting. . . 84 XIV VGA comparison . . . 88 LIST OF FIGURE FIGURE I 2", 3 and 4'" order sigma-delta modulator SNR vs. input... level . . . . Page 2 Block diagram of a direct conversion receiver. 3 Single transistor transconductor 4 Differential pair 5 Source degeneration amplifier. 6 Four-quadrant multiplier basic architectures . . . . . . . . 10 7 Multiplier as a...

Tan, Siang Tong

2012-06-07T23:59:59.000Z

27

Vacuum electron acceleration by using two variable frequency laser pulses  

SciTech Connect (OSTI)

A method is proposed for producing a relativistic electron bunch in vacuum via direct acceleration by using two frequency-chirped laser pulses. We consider the linearly polarized frequency-chiped Hermit-Gaussian 0, 0 mode lasers with linear chirp in which the local frequency varies linearly in time and space. Electron motion is investigated through a numerical simulation using a three-dimensional particle trajectory code in which the relativistic Newton's equations of motion with corresponding Lorentz force are solved. Two oblique laser pulses with proper chirp parameters and propagation angles are used for the electron acceleration along the z-axis. In this way, an electron initially at rest located at the origin could achieve high energy, ?=319 with the scattering angle of 1.02{sup ?} with respect to the z-axis. Moreover, the acceleration of an electron in different initial positions on each coordinate axis is investigated. It was found that this mechanism has the capability of producing high energy electron microbunches with low scattering angles. The energy gain of an electron initially located at some regions on each axis could be greatly enhanced compared to the single pulse acceleration. Furthermore, the scattering angle will be lowered compared to the acceleration by using laser pulses propagating along the z-axis.

Saberi, H.; Maraghechi, B. [Department of Physics, Amirkabir University of Technology, 15875-4413 Tehran (Iran, Islamic Republic of)] [Department of Physics, Amirkabir University of Technology, 15875-4413 Tehran (Iran, Islamic Republic of)

2013-12-15T23:59:59.000Z

28

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

E-Print Network [OSTI]

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...

Han, Xu

2012-02-14T23:59:59.000Z

29

Enhanced Recovery Utilizing Variable Frequency Drives and a Distributed Power System  

SciTech Connect (OSTI)

This report describes complete results of the project entitled ''Enhanced Recovery Utilizing Variable Frequency Drives and a Distributed Power System''. This demonstration project was initiated in July 2003 and completed in March 2005. The objective of the project was to develop an integrated power production/variable frequency drive system that could easily be deployed in the oil field that would increase production and decrease operating costs. This report describes all the activities occurred and documents results of the demonstration.

Randy Peden; Sanjiv Shah

2005-07-26T23:59:59.000Z

30

Stressing of turbine-generator-exciter shafts by variable-frequency currents superimposed on DC currents in asynchronous HVDC links and following disturbances at converter stations  

SciTech Connect (OSTI)

Ripple currents on the DC side of both HVDC synchronous and asynchronous. Links together with cleared HVDC and AC system disturbances can excite in some circumstances onerous torsional vibrations in large steam generator shafts. The problem has assumed importance in recent months on account of the HVDC Link between Scotland and Northern Ireland going ahead, on account of the proposed Eire/Wales Link, and because AC/DC/AC couplers are to be installed extensively to interconnect the East and West European Grid Systems. This paper discusses and analyses excitation of shaft torsional vibrations in steam turbine-generator-exciter shafts in close proximity to HVDC converter stations by (1) variable-frequency ripple currents superimposed on the DC currents in asynchronous Links, and (2) disturbances at bi-polar converter stations. The time response and tables show that for the systems studied variable-frequency ripple currents superimposed on the DC current in asynchronous Links can excite shaft torsional vibrations, the very small noncharacteristic currents could result in onerous shaft torques which might damage the machine, and that DC line faults at converter stations in close proximity of steam turbine-generator units can excite onerous turbine-generator shaft torsional response. Detailed simulation of the HVDC converter and generator is necessary for precise assessments of shaft torsional response following HVDC converter station faults. 500MW, 660MW, 1000MW and 1300MW machines are considered in the analyses that are made.

Hammons, T.J.; Bremner, J.J. (Univ. of Glasgow (United Kingdom))

1994-09-01T23:59:59.000Z

31

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

E-Print Network [OSTI]

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...

Sulistyono, Widodo

1994-01-01T23:59:59.000Z

32

On the efficiency of electrical submersible pumps equipped with variable frequency drives: A field study  

SciTech Connect (OSTI)

A field study was conducted on 18 electrical-submersible-pump- (ESP-) equipped wells operating in the Williston basin. Fifteen of these wells were run with variable frequency drives (VFD`s). The purpose of the study was to determine the efficiency and operating characteristics of ESP`s operating with VFD`s and compare them to those without. Voltage, current, power, and frequency were measured at the drive input, the drive output, and ESP input. Production data were recorded and power and efficiency were calculated at all measurement locations and compared to published data.

Patterson, M.M. [Patterson (Maurice M.), Hemphill, TX (United States)

1996-02-01T23:59:59.000Z

33

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

E-Print Network [OSTI]

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

Amirabadi, Mahshid

2013-08-07T23:59:59.000Z

34

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

E-Print Network [OSTI]

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.

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

1995-08-17T23:59:59.000Z

35

Analysis of variable-frequency currents superimposed on DC currents in asynchronous HVDC Links in stressing turbine-generator-exciter shafts  

SciTech Connect (OSTI)

Ripple currents on the DC side of both HVDC asynchronous and synchronous Links can excite in some circumstances onerous torsional vibrations in large steam generator shafts. The problem has assumed importance in recent months on account of the HVDC Link between Scotland and Northern Ireland going ahead, on account of the proposed Eire/Wales Link, because AC/DC/AC couplers are to be installed to interconnect the East and West European Grid Systems, and because resonances have been observed on machines in close proximity to AC/DCIAC couplers and HVDC Links. This paper discusses and analyses excitation of shaft torsional vibrations in steam turbine-generator-exciter shafts in close proximity to HVDC converter stations by variable-frequency ripple currents superimposed on DC currents in asynchronous Links. It presents technical knowledge not arranged for convenient reference heretofore in studying possible excitation of turbine-generator-v/ exciter shaft torsional vibrations by non-characteristic HVDC converter harmonic currents if a machine should be considered to be at risk. Shaft torques in multi-machine networks are evaluated by proportioning HVDC Link disturbance currents to each machine at risk using system network data, generator data and fault analysis data considering frequency dependence of the system parameters. This scaling factor is calculated for different scenarios of system operation and load. Equivalent circuits for the synchronous generator are employed appropriately to correlate HVDC Link disturbance current impressed on the generator stator with s state torque excitation from which magnitude of turbine-generator-exciter shaft torque is deduced.

Hammons, T.J.; Bremner, J.J. [Univ. of Glasgow (United Kingdom)] [Univ. of Glasgow (United Kingdom)

1995-03-01T23:59:59.000Z

36

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

E-Print Network [OSTI]

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 ...

Sánchez-Martínez, Gabriel Eduardo

2013-01-01T23:59:59.000Z

37

Measured Savings of DC to AC Drive Retrofit in Plastic Extrusion  

E-Print Network [OSTI]

This paper presents the potential electrical energy efficiency improvements for utilizing alternating current (AC) motors controlled by variable frequency drives (VFD) in place of direct current (DC) motors to drive plastic extrusion machines. A...

Sfeir, R. A.

2008-01-01T23:59:59.000Z

38

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

SciTech Connect (OSTI)

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.

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

2011-12-01T23:59:59.000Z

39

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

E-Print Network [OSTI]

for calculation of joint-event probabilities from the bi-variate normal distribution as follows: X and Y are random variables following a bi- variate normal distribution with zero means, unit variances and correlation coefficient p. Then: Pr [X & h, Y 2 k) = L... 1956-1960. Despite many useful applications, the calculation of frequencies or probabilities for specified events is somewhat limited to the class selections of the variables chosen for the study. Moreover, relative humidity is not a good indicator...

Zeitler, Jon William

1991-01-01T23:59:59.000Z

40

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

E-Print Network [OSTI]

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...

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

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

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

E-Print Network [OSTI]

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...

Liou, S. P.; Aguiar, D.

42

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

E-Print Network [OSTI]

tied energy storage systems (ESS) will be voltage to a high-DC/AC converter to interface ESS based on low voltage cellscharging and discharging of the ESS and the control strategy

King Jet, TSENG

2013-01-01T23:59:59.000Z

43

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

SciTech Connect (OSTI)

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.

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

2010-12-20T23:59:59.000Z

44

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

SciTech Connect (OSTI)

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

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

2013-01-01T23:59:59.000Z

45

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

E-Print Network [OSTI]

on the theoretical and practical application of the analysis method comes directly from this reference. B. Fundamental Assum tions of Power S ectrum Theor Consider a function of time X(t), such as wind speed, which is generated by a random process. Then the value... of the function X(t) at any particular point in time is a random variable. This random process may or may not have a Gaussian or normal distribution but it is a fundamental assumption (at least in the development of the theory) that the random process...

Cornett, John Sheldon

1966-01-01T23:59:59.000Z

46

Low-frequency variability and heat transport in a low-order nonlinear coupled ocean-atmosphere model  

E-Print Network [OSTI]

We formulate and study a low-order nonlinear coupled ocean-atmosphere model with an emphasis on the impact of radiative and heat fluxes and of the frictional coupling between the two components. This model version extends a previous 24-variable version by adding a dynamical equation for the passive advection of temperature in the ocean, together with an energy balance model. The bifurcation analysis and the numerical integration of the model reveal the presence of low-frequency variability (LFV) concentrated on and near a long-periodic, attracting orbit. This orbit combines atmospheric and oceanic modes, and it arises for large values of the meridional gradient of radiative input and of frictional coupling. Chaotic behavior develops around this orbit as it loses its stability; this behavior is still dominated by the LFV on decadal and multi-decadal time scales that is typical of oceanic processes. Atmospheric diagnostics also reveals the presence of predominant low- and high-pressure zones, as well as of a subtropical jet; these features recall realistic climatological properties of the oceanic atmosphere. Finally, a predictability analysis is performed. Once the decadal-scale periodic orbits develop, the coupled system's short-term instabilities --- as measured by its Lyapunov exponents --- are drastically reduced, indicating the ocean's stabilizing role on the atmospheric dynamics. On decadal time scales, the recurrence of the solution in a certain region of the invariant subspace associated with slow modes displays some extended predictability, as reflected by the oscillatory behavior of the error for the atmospheric variables at long lead times.

Stéphane Vannitsem; Jonathan Demaeyer; Lesley De Cruz; Michael Ghil

2014-12-01T23:59:59.000Z

47

The frequency dependent impedance of an HVdc converter  

SciTech Connect (OSTI)

A linear and direct method of determining the frequency dependent impedance of a 12 pulse HVdc converter is presented. Terms are developed for both the dc and ac side impedances of the converter, including the effect of the firing angle control system, the commutation period, and the variability of the commutation period. The impedance predictions are verified by dynamic simulation.

Wood, A.R.; Arrillaga, J. [Univ. of Canterbury, Christchurch (New Zealand)] [Univ. of Canterbury, Christchurch (New Zealand)

1995-07-01T23:59:59.000Z

48

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism inS-4500II FieldVacancy-InducedCloudPoissonVampire

49

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

E-Print Network [OSTI]

of Variable Renewable Generation The report is accompaniedit Relates to Wind-Powered Generation. LBNL-XXXX. Berkeley:with Increased Wind Generation. LBNL-XXXX. Berkeley:

Eto, Joseph H.

2011-01-01T23:59:59.000Z

50

Chapter 18: Variable Frequency Drive Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures: September 2011 … December 2014  

Energy Savers [EERE]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energyon ArmedWaste andAccessCO2 Injection Begins8: Variable Frequency Drive Evaluation

51

Power links with Ireland -- Excitation of turbine-generator shaft torsional vibrations by variable frequency currents superimposed on DC currents in asynchronous HVDC links  

SciTech Connect (OSTI)

The paper describes an in-depth analysis of excitation of shaft torsional vibrations in steam-turbine-generator-exciter shafts in close proximity to HVDC converter stations by variable-frequency ripple currents superimposed on the DC currents in asynchronous Links. It extends earlier work to include an in depth analysis of system scaling factors for harmonic currents impressed on generators in Northern Ireland by an inverter and to investigate the phenomena for possible torsional vibrations in the generators by the Link. Frequencies at which shaft torsional vibrations would be excited by modulation product harmonics in 50Hz/50Hz asynchronous Links as a function of deviation in system frequency is reviewed. Relative noncharacteristic current levels for 50Hz/50Hz connectors are illustrated assuming ripple currents at the inverter which gives realistic harmonic voltages in a twelve-pulse bridge. The paper then shows that torques in machines in multi-machine networks may be estimated by proportioning HVDC link harmonic disturbance current appropriately to each machine at risk. It is concluded that variable-frequency ripple currents superimposed on the DC current in asynchronous links can excite sympathetic torsional vibrations in turbine-generator-exciter shafts.

Hammons, T.J.; Tay, B.W.; Kok, K.L. [Glasgow Univ. (United Kingdom)] [Glasgow Univ. (United Kingdom)

1995-08-01T23:59:59.000Z

52

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

E-Print Network [OSTI]

Responsive Reserve Report. WECC Frequency Responsive Reserve=&View={BB5A76DA-21C8-48FC-9468-F82B395DF8F9} WECC.2008. WECC Standard BAL-002-WECC-1 - Contingency Reserves.

Eto, Joseph H.

2011-01-01T23:59:59.000Z

53

Entangling the optical frequency comb: simultaneous generation of multiple 2x2 and 2x3 continuous-variable cluster states in a single optical parametric oscillator  

E-Print Network [OSTI]

We report on our research effort to generate large-scale multipartite optical-mode entanglement using as few physical resources as possible. We have previously shown that cluster- and GHZ-type N-partite continuous-variable entanglement can be obtained in an optical resonator that contains a suitably designed second-order nonlinear optical medium, pumped by at most O(N^2) fields. In this paper, we show that the frequency comb of such a resonator can be entangled into an arbitrary number of independent 2x2 and 2x3 continuous-variable cluster states by a single optical parametric oscillator pumped by just a few optical modes.

Hussain Zaidi; Nicolas C. Menicucci; Steven T. Flammia; Russell Bloomer; Matthew Pysher; Olivier Pfister

2010-10-25T23:59:59.000Z

54

Analysis on the energy efficiency of variable-frequency air conditioners (Hitachi models as an example) Jim Jr-Min Lin 2014.09.26  

E-Print Network [OSTI]

Analysis on the energy efficiency of variable-frequency air conditioners (Hitachi models (Max) Energy Efficiency @min load Energy Efficiency @Max load kW kW kW kW W/W W/W RAS-22NB 1.00 3.20 0 Efficiency @min load Energy Efficiency @Max load kW kW kW kW W/W W/W RAM-5FNS(B) - 12.5 - 2.91 - 4.3 RAM-6FNS

55

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

SciTech Connect (OSTI)

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

Mohan, N.

1981-09-01T23:59:59.000Z

56

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

SciTech Connect (OSTI)

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.

Deng, Yi

2014-11-24T23:59:59.000Z

57

I: Low Frequency NMR and NQR Using a dc SQUID. II: Variable-temperature 13C CP/MAS of Organometallics  

SciTech Connect (OSTI)

NMR and NQR at low frequencies are difficult prospects due to small nuclear spin polarization. Furthermore, the sensitivity'of the inductive pickup circuitry of standard spectrometers is reduced as the frequency is lowered. I have used a cw-SQUID (Superconducting QUantum Interference Device) spectrometer, which has no such frequency dependence, to study the local atomic environment of {sup 14}N via the quadrupolar interaction. Because {sup 14}N has spin I = 1 and a 0-6 MHz frequency range, it is not possible to obtain well-resolved spectra in high magnetic fields. I have used a technique to observe {sup 14}N NQR resonances via their effect on neighboring protons mediated by the heteronuclear dipolar interaction to study peptides and narcotics. The sensitivity of the SQUID is not enough to measure low-frequency surface (or other low spin density) systems. The application of spin-polarized xenon has been previously used to enhance polarization in conventional NMR experiments. Because xenon only polarizes spins with which it is in contact, it is surface selective. While differences in chemical shifts between surface and bulk spins are not large, it is expected that the differences in quadrupole coupling constant should be very large due to the drastic change of the electric field gradient surrounding spins at the surface. With this in mind, I have taken preliminary steps to measure SQUID detected polarization transfer from Xe to another spin species at 4.2 K and in small magnetic fields (<50 G). In this regime, the spin-lattice relaxation of xenon is dependent on the applied magnetic field. The results of our efforts to characterize the relaxation of xenon are presented. The final section describes the solid-state variable-temperature (VT) one- and two-dimensional {sup 13}C cross polarization (CP)/magic angle spinning (MAS) NMR of Hf({eta}{sup 5}-C{sub 5}H{sub 5}){sub 2}({eta}{sup 1}-C{sub 5}H{sub 5}){sub 2}, Zr({eta}{sup 5}-C{sub 5}H{sub 5}){sub 3}({eta}{sup 1}-C{sub 5}H{sub 5}) and Sn({eta}{sup 1}-C{sub 5}H{sub 5}){sub 4}. This work was undertaken in the hope of gaining insight into the intramolecuhrr dynamics, specifically which fluxional processes exist in the solid state, by what mechanism rearrangements are occurring, and the activation energies by which these processes are governed.

Ziegeweid, M.A.

1995-11-29T23:59:59.000Z

58

RHIC spin flipper AC dipole controller  

SciTech Connect (OSTI)

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

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

2011-03-28T23:59:59.000Z

59

Making an Energy Histogram Using Pierre Auger Observatory Surface Detector Data A histogram is essentially a graphical representation of the frequency or distribution of a variable over specific intervals  

E-Print Network [OSTI]

Making an Energy Histogram Using Pierre Auger Observatory Surface Detector Data Histogram A histogram is essentially a graphical representation of the frequency or distribution of a variable over energies. Before you start you should know that: o This set of instructions only assumes a very minimal

60

Frequency modulation drive for a piezoelectric motor  

DOE Patents [OSTI]

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.

Mittas, Anthony (Albuquerque, NM)

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Effective switching frequency multiplier inverter  

DOE Patents [OSTI]

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.

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

2007-08-07T23:59:59.000Z

62

www.swansea.ac.uk Health & Safety Office  

E-Print Network [OSTI]

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

Martin, Ralph R.

63

ac josephson effect: Topics by E-print Network  

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

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

64

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)

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.

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

1995-06-01T23:59:59.000Z

65

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

E-Print Network [OSTI]

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

Silva, Filipe Faria Da

66

Power conversion architecture for grid interface at high switching frequency  

E-Print Network [OSTI]

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 ...

Lim, Seungbum

67

Microfabricated AC impedance sensor  

DOE Patents [OSTI]

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

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

2002-01-01T23:59:59.000Z

68

Monitoring method and apparatus using high-frequency carrier  

DOE Patents [OSTI]

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.

Haynes, H.D.

1996-04-30T23:59:59.000Z

69

CD54AC04, CD74AC04 HEX INVERTERS  

E-Print Network [OSTI]

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

Kretchmar, R. Matthew

70

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

DOE Patents [OSTI]

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.

Pitel, I.J.

1987-02-03T23:59:59.000Z

71

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

DOE Patents [OSTI]

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.

Pitel, Ira J. (Whippany, NJ)

1987-02-03T23:59:59.000Z

72

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS--I: FUNDAMENTAL THEORY AND APPLICATIONS, VOL. 49, NO. 5, MAY 2002 621 Modeling of PWM Inverter-Supplied AC Drives  

E-Print Network [OSTI]

. The fundamental frequency of this waveform is adjusted to produce the desired speed. In modern electric drives, MAY 2002 621 Modeling of PWM Inverter-Supplied AC Drives at Low Switching Frequencies T. A. Sakharuk in ac drives supplied by pulsewidth modulated (PWM) power electronic inverters. Specifically, the paper

Stankoviæ, Aleksandar

73

Study of AC/RF properties of SRF ingot niobium  

SciTech Connect (OSTI)

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

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

2013-09-01T23:59:59.000Z

74

Ac-Ac Dual Active Bridge Converter for Solid State Transformer  

E-Print Network [OSTI]

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

Kimball, Jonathan W.

75

Soft switched high frequency ac-link converter  

E-Print Network [OSTI]

place through the 16 modes: energizing, partial reso- nance and de-energizing. The link is energized from the inputs during modes 1, 3, 9 and 11 and is de-energized to the outputs during modes 5, 7, 13 and 15. Modes 2, 4, 6, 8, 10, 12, 14 and 16... are the partial resonant modes and as evident from Fig. 14, they make up only a very small fraction of the link cycle time. The various operating modes are explained below. Mode 1 (Energizing): As discussed in section xyz, of the chosen phase pairs, the one having...

Balakrishnan, Anand Kumar

2009-05-15T23:59:59.000Z

76

AC and DC power transmission  

SciTech Connect (OSTI)

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

Not Available

1985-01-01T23:59:59.000Z

77

Self-induced ac Stark shift in lasers  

SciTech Connect (OSTI)

The ac Stark effect is a well-known, well-established effect associated with the displacement of the atomic energy levels in the presence of an electromagnetic (e.m.) field. As the origin of the e.m. field is irrelevant, a self-induced ac Stark effect should be present in a laser. However, not only has this effect never been reported but it is not included in any laser model. Here, we show that a self-induced ac Stark shift does exist in the theoretical description of a two-level laser, provided that the reduced equations are derived not from the rotating-wave approximation, but from the full density matrix formulation. Interesting fundamental consequences are discussed and quantitative estimates of the self-induced frequency shift resulting from the laser field's ac Stark shift are obtained for a variety of lasers. We find that the effect is generally small but (at least in some cases) measurable and that the transfer of laser amplitude noise into frequency noise may play a role in future, ultrahigh-precision metrological applications.

Gil, L.; Lippi, G. L. [Universite de Nice Sophia Antipolis, Institut Non Lineaire de Nice, and CNRS, UMR 6618 1361 Route des Lucioles, F-06560 Valbonne (France)

2011-04-15T23:59:59.000Z

78

Free piston variable-stroke linear-alternator generator  

DOE Patents [OSTI]

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.

Haaland, C.M.

1998-12-15T23:59:59.000Z

79

Free piston variable-stroke linear-alternator generator  

DOE Patents [OSTI]

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.

Haaland, Carsten M. (Dadeville, AL)

1998-01-01T23:59:59.000Z

80

AC resistance measuring instrument  

DOE Patents [OSTI]

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

Hof, P.J.

1983-10-04T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Determining Hydrological Controls on Flood Frequency | U.S. DOE...  

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

increasing aridity, variability increases. In contrast, BFI was found to exert a second-order control on flood frequency. Higher BFI, meaning higher contributions of subsurface...

82

A Preliminary Experimental Study on Haptic Teleoperation of Mobile Robot with Variable Force Feedback Gain  

E-Print Network [OSTI]

industrial constructions, etc. In all these application examples human-robot interfaces play the key role and its application for e-mail:ildar.info@gmail.com e-mail:jhryu@kut.ac.kr e-mail:robot@dgist.ac.kr O Y XA Preliminary Experimental Study on Haptic Teleoperation of Mobile Robot with Variable Force

Ryu, Jee-Hwan

83

Absorption of ac fields in amorphous indium-oxide films  

SciTech Connect (OSTI)

Absorption data from applied ac fields in Anderson-localized amorphous indium-oxide (In{sub x}O) films are shown to be frequency and disorder dependent. The absorption shows a roll-off at a frequency which is much lower than the electron-electron scattering rate of the material when it is in the diffusive regime. This is interpreted as evidence for discreteness of the energy spectrum of the deeply localized regime. This is consistent with recent many-body localization scenarios. As the metal-insulator transition is approached, the absorption shifts to higher frequencies. Comparing with the previously obtained results on the crystalline version of indium-oxide (In{sub 2}O{sub 3?x}) implies a considerably higher inelastic electron-phonon scattering rate in the amorphous material. The range over which the absorption versus frequency decreases may indicate that a wide distribution of localization length is a common feature in these systems.

Ovadyahu, Z. [Racah Institute of Physics, the Hebrew University, Jerusalem 91904 (Israel)

2014-08-20T23:59:59.000Z

84

Condensed Representation of Sequential Patterns According to Frequency-Based  

E-Print Network [OSTI]

Condensed Representation of Sequential Patterns According to Frequency-Based Measures Marc Nacre, 14032 Caen Cedex, France Abstract. Condensed representations of patterns are at the core of many, we tackle sequential data and we define an exact condensed representation for sequential patterns ac

Boyer, Edmond

85

Cataclysmic Variables  

E-Print Network [OSTI]

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.

Robert Connon Smith

2007-01-23T23:59:59.000Z

86

Exchange 13/14 www.ed.ac.uk  

E-Print Network [OSTI]

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

Herrmann, Samuel

87

Quantum recurrence and fractional dynamic localization in ac-driven perfect state transfer Hamiltonians  

SciTech Connect (OSTI)

Quantum recurrence and dynamic localization are investigated in a class of ac-driven tight-binding Hamiltonians, the Krawtchouk quantum chain, which in the undriven case provides a paradigmatic Hamiltonian model that realizes perfect quantum state transfer and mirror inversion. The equivalence between the ac-driven single-particle Krawtchouk Hamiltonian H{sup -hat} (t) and the non-interacting ac-driven bosonic junction Hamiltonian enables to determine in a closed form the quasi energy spectrum of H{sup -hat} (t) and the conditions for exact wave packet reconstruction (dynamic localization). In particular, we show that quantum recurrence, which is predicted by the general quantum recurrence theorem, is exact for the Krawtchouk quantum chain in a dense range of the driving amplitude. Exact quantum recurrence provides perfect wave packet reconstruction at a frequency which is fractional than the driving frequency, a phenomenon that can be referred to as fractional dynamic localization.

Longhi, Stefano, E-mail: stefano.longhi@fisi.polimi.it

2014-06-15T23:59:59.000Z

88

Cyclic strain hardening of nanocrystalline nickel B. Moser a,b,*, T. Hanlon a,c  

E-Print Network [OSTI]

Cyclic strain hardening of nanocrystalline nickel B. Moser a,b,*, T. Hanlon a,c , K.S. Kumar d , S strain hardening and frequency-dependent fatigue life in electrodeposited nanocrystalline Ni subjected. All rights reserved. Keywords: Nanocrystalline materials; Nickel; Low cycle fatigue; Fracture; Cyclic

Suresh, Subra

89

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

E-Print Network [OSTI]

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

Katsumoto, Shingo

90

CD54AC08, CD74AC08 QUADRUPLE 2-INPUT POSITIVE-AND GATES  

E-Print Network [OSTI]

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

Kretchmar, R. Matthew

91

Bayesian latent variable modelling in studies of air pollution and health  

E-Print Network [OSTI]

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 the approach adopted for modelling the trend and correlation. KEYWORDS: Air pollution and health; Bayesian

Burton, Geoffrey R.

92

Processing of superconductive materials and high frequency  

SciTech Connect (OSTI)

We do not know yet if superconductivity will become useful without refrigeration. Now, the superconductors are so different from copper that it is difficult to imagine replacing copper with such a brittle material. Superconductors conduct dc with no loss, ac with small losses, and microwaves in co-axial lines with almost no loss and with no dispersion from dc to the highest frequencies. They will probably allow us to close the gap between radio frequency and infrared optical transmission. Clearly your industry should know some things about where superconductivity may lead us and must consider whether the greater risk is to develop them or to let others try it. There are no easy answers yet.

Smith, J.L.

1987-01-01T23:59:59.000Z

93

AC electrokinetic manipulation of selenium nanoparticles for potential nanosensor applications  

SciTech Connect (OSTI)

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.

Mahmoodi, Seyed Reza [School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Bayati, Marzieh, E-mail: m-bayati@tums.ac.ir [School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Hosseinirad, Somayeh [School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Foroumadi, Alireza [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Gilani, Kambiz [Department of Pharmaceutics, School of Pharmacy, Tehran University of Medical Science, Tehran (Iran, Islamic Republic of); Rezayat, Seyed Mahdi [School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

2013-03-15T23:59:59.000Z

94

Assessment of US electric vehicle programs with ac powertrains  

SciTech Connect (OSTI)

AC powertrain technology is a promising approach to improving the performance of electric vehicles. Four major programs are now under way in the United States to develop ac powertrains: the Ford/General Electric single-shaft electric propulsion system (ETX-II), the Eaton dual-shaft electric propulsion system (DSEP), the Jet Propulsion Laboratories (JPL) integrated ac motor drive and recharge system, and the Massachusetts Institute of Technology (MIT) variable reluctance motor (VRM) drive. The JPL program is sponsored by EPRI; the other three programs are funded by the US Department of Energy. This preliminary assessment of the four powertrain programs focuses on potential performance, costs, safety, and commercial feasibility. Interviews with program personnel were supplemented by computer simulations of electric vehicle performance using the four systems. Each of the four powertrains appears superior to standard dc powertrain technology in terms of performance and weight. The powertrain technologies studied in this assessment are at varying degrees of technological maturity. One or more of the systems may be ready for incorporation into an advanced electric vehicle during the early 1990s. Each individual report will have a separate abstract. 5 refs., 37 figs., 29 tabs.

Kevala, R.J. (Booz, Allen and Hamilton, Inc., Bethesda, MD (USA). Transportation Consulting Div.)

1990-02-01T23:59:59.000Z

95

Variable Frequency Drives: Energy Savings and Impact on Motor Performance  

E-Print Network [OSTI]

, and Pitfalls: Motor Acoustic Noise, Motor Heating. This paper is intended for plant engineers and maintenance personnel who have some practical experience with electrical and mechanical equipment, but are not VFD experts....

Petro, D.

96

New nonlinear mechanisms of midlatitude atmospheric low-frequency variability  

E-Print Network [OSTI]

and Atmospheric Research Utrecht, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands Abstract

97

Conserving Energy in Blast Freezers Using Variable Frequency Drives  

E-Print Network [OSTI]

University Portland Greg Wheeler Director Industrial Assessment Center ABSTRACT A stationary blast freezer processing 22 -lb cartons of sardines in 19,000 pound lots was modified to improve efficiency and to conserve energy. Baffles... of Portland showed readings to agree within 1%. The procedure for measuring velocity profiles was to position the operator in the blast-cell with doors closed, downstream of the pack, prior to opening the refrigeration valve. We thus assumed...

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

2004-01-01T23:59:59.000Z

98

CD54AC02, CD74AC02 QUADRUPLE 2-INPUT POSITIVE-NOR GATES  

E-Print Network [OSTI]

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

Kretchmar, R. Matthew

99

CD54AC32, CD74AC32 QUADRUPLE 2-INPUT POSITIVE-OR GATES  

E-Print Network [OSTI]

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

Kretchmar, R. Matthew

100

Eastern Frequency Response Study  

SciTech Connect (OSTI)

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.

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

2013-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

AC corrosion on cathodically protected steel.  

E-Print Network [OSTI]

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

Torstensen, Andreas

2012-01-01T23:59:59.000Z

102

Frequency selective infrared sensors  

SciTech Connect (OSTI)

A frequency selective infrared (IR) photodetector having a predetermined frequency band. The exemplary frequency selective photodetector includes: a dielectric IR absorber having a first surface and a second surface substantially parallel to the first surface; an electrode electrically coupled to the first surface of the dielectric IR absorber; and a frequency selective surface plasmonic (FSSP) structure formed on the second surface of the dielectric IR absorber. The FSSP structure is designed to selectively transmit radiation in the predetermined frequency band that is incident on the FSSP structure substantially independent of the angle of incidence of the incident radiation on the FSSP structure.

Davids, Paul; Peters, David W

2014-11-25T23:59:59.000Z

103

Frequency selective infrared sensors  

DOE Patents [OSTI]

A frequency selective infrared (IR) photodetector having a predetermined frequency band. The exemplary frequency selective photodetector includes: a dielectric IR absorber having a first surface and a second surface substantially parallel to the first surface; an electrode electrically coupled to the first surface of the dielectric IR absorber; and a frequency selective surface plasmonic (FSSP) structure formed on the second surface of the dielectric IR absorber. The FSSP structure is designed to selectively transmit radiation in the predetermined frequency band that is incident on the FSSP structure substantially independent of the angle of incidence of the incident radiation on the FSSP structure.

Davids, Paul; Peters, David W

2013-05-28T23:59:59.000Z

104

In: Speech Communication 26(4), pp. 259-282 (December 1998) URL: http://www.dcs.shef.ac.uk/~miguel/papers/dim red epg.html  

E-Print Network [OSTI]

://www.dcs.shef.ac.uk/~miguel/papers/dim red epg.html Dimensionality Reduction of Electropalatographic Data Using Latent Variable Models Miguel: electropalatography (EPG), articulatory modelling, data reduction methods, dimensionality reduction, latent variable of finding such a dimensionality reduction mapping, not from a physical point of view, but from a machine

Carreira-Perpiñán, Miguel Á.

105

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

E-Print Network [OSTI]

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

No, Jong-Seon

106

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

Energy Savers [EERE]

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

107

Radio frequency detection assembly and method for detecting radio frequencies  

DOE Patents [OSTI]

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.

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

2010-03-16T23:59:59.000Z

108

Understanding Inertial and Frequency Response of Wind Power Plants: Preprint  

SciTech Connect (OSTI)

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).

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

2012-07-01T23:59:59.000Z

109

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

E-Print Network [OSTI]

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

Matsuzaki, Katsuhiko

110

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

E-Print Network [OSTI]

................................................................................................ 71 Table 10: Case III-B Result .............................................................................................. 72 Table 11: Case IV-A Result...

Ozkentli, Esra

2012-10-19T23:59:59.000Z

111

Low Frequency Transmission Final Project Report  

E-Print Network [OSTI]

to HVDC transmission and conventional AC transmission in different configurations. The issue is quite

112

Changes in hydrological extremes and climate variability in the Severn Uplands.  

E-Print Network [OSTI]

??Hydrological extremes within the UK have increased in intensity, frequency and persistence over recent years and are predicted to increase in variability throughout the 21st… (more)

Biggs, Eloise M.

2009-01-01T23:59:59.000Z

113

Frequency Response Analysis Tool  

SciTech Connect (OSTI)

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.

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

2014-12-31T23:59:59.000Z

114

Beat Frequency Modulation of T Tauri Accretion Rates  

E-Print Network [OSTI]

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.

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

1995-04-10T23:59:59.000Z

115

ICI Canceling Space-Frequency Block Code for MISO-OFDM in Fast Fading Channels  

E-Print Network [OSTI]

ICI Canceling Space-Frequency Block Code for MISO-OFDM in Fast Fading Channels Jae Yeun Yun, Eui}@ee.kaist.ac.kr Abstract-- An intercarrier interference (ICI) canceling technique for multiple-input single-output (MISO) at the receiver for multiple-input single-output (MISO) systems. The code design is based on the approximated

Lee, Yong Hoon

116

Stabilized radio frequency quadrupole  

DOE Patents [OSTI]

Disclosed is 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. 5 figs.

Lancaster, H.D.; Fugitt, J.A.; Howard, D.R.

1984-12-25T23:59:59.000Z

117

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

SciTech Connect (OSTI)

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.

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)

2014-05-15T23:59:59.000Z

118

Microfabricated ion frequency standard  

DOE Patents [OSTI]

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.

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)

2010-12-28T23:59:59.000Z

119

Solid State AC Motor Drives - Conservation Perspectives  

E-Print Network [OSTI]

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

Mohan, N.; Ferraro, R. J.

1982-01-01T23:59:59.000Z

120

Mechanically tunable plasma frequency  

E-Print Network [OSTI]

in S12 phases. function [eps, x] = FindPerm(Thru, Sample,It returns the permittivity (eps) and a frequency matrix %0; % Initialize results matrix eps = zeros(n,1); for i = 1:n

Schuil, Crystal Joy

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Graphene Frequency Multipliers  

E-Print Network [OSTI]

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 ...

Wang, Han

122

THE CARINA PROJECT. VI. THE HELIUM-BURNING VARIABLE STARS  

SciTech Connect (OSTI)

We present new optical (BVI) time-series data for the evolved variable stars in the Carina dwarf spheroidal galaxy. The quality of the data and the observing strategy allowed us to identify 14 new variable stars. Eight out of the 14 are RR Lyrae (RRL) stars, 4 are Anomalous Cepheids (ACs), and 2 are geometrical variables. Comparison of the period distribution for the entire sample of RRLs with similar distributions in nearby dwarf spheroidal galaxies and in the Large Magellanic Cloud indicates that the old stellar populations in these systems share similar properties. This finding is also supported by the RRL distribution in the Bailey diagram. On the other hand, the period distribution and the Bailey diagram of ACs display significant differences among the above stellar systems. This evidence suggests that the properties of intermediate-age stellar populations might be affected both by environmental effects and structural parameters. We use the BV Period-Wesenheit (PW) relation of RRLs together with evolutionary prescriptions and find a true distance modulus of 20.09 {+-} 0.07 (intrinsic) {+-} 0.1 (statistical) mag that agrees quite well with similar estimates available in the literature. We identified four peculiar variables. Taking into account their position in the Bailey diagram and in the BV PW relation, two of them (V14 and V149) appear to be candidate ACs, while two (V158 and V182) might be peculiar RRLs. In particular, the variable V158 has a period and a V-band amplitude very similar to the low-mass RRL-RRLR-02792-recently identified by Pietrzynski et al. in the Galactic bulge.

Coppola, G.; Marconi, M.; Ripepi, V.; Dall'Ora, M.; Musella, I. [INAF-Osservatorio Astronomico di Capodimonte, Via Moiariello 16, I-80131 Napoli (Italy); Stetson, P. B. [Dominion Astrophysical Observatory, NRC-Herzberg, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Bono, G.; Buonanno, R. [Dipartimento di Fisica-Universita di Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Roma (Italy); Fabrizio, M. [INAF-Osservatorio Astronomico di Collurania, via M. Maggini, I-64100 Teramo (Italy); Ferraro, I.; Iannicola, G.; Pulone, L. [INAF-Osservatorio Astronomico di Roma, Via Frascati 33, I-00040 Monte Porzio Catone (Italy); Fiorentino, G. [INAF-Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Monelli, M. [Instituto de Astrofisica de Canarias, Calle Via Lactea s/n, E-38205 La Laguna, Tenerife (Spain); Nonino, M. [INAF-Osservatorio Astronomico di Trieste, via G. B. Tiepolo 11, I-40131 Trieste (Italy); Thevenin, F. [Universite de Nice-Sophia Antipolis, Lab. Lagrange, UMR 7293, Observatoire de la Cote dAzur, BP 4229, F-06304 Nice (France); Walker, A. R., E-mail: coppola@na.astro.it [Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena (Chile)

2013-09-20T23:59:59.000Z

123

Comparing Images Under Variable Illumination David W. Jacobs Peter N. Belhumeur Ronen Basri  

E-Print Network [OSTI]

-based vision an effort is made to represent the set of all images an object can produce, either by sam- plingComparing Images Under Variable Illumination David W. Jacobs Peter N. Belhumeur Ronen Basri NEC@wisdom.weizmann.ac.il belhumeur@yale.edu Abstract We consider the problem of determining whether two images come from different

Yang, Junfeng

124

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

E-Print Network [OSTI]

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

Aickelin, Uwe

125

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

E-Print Network [OSTI]

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

Bahk, Saewoong

126

Three phase AC motor controller  

DOE Patents [OSTI]

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.

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

1984-03-20T23:59:59.000Z

127

Interrelationship of variables concerned in a swine testing program  

E-Print Network [OSTI]

'~. ~ - sort'. : ?. 1 carr, , l: t" cna (cxlcu- lated ';" t~. a !. n-rs) c:ana lanai sad nonsi, nific. "nt in;. . ll nhanas ax I he (ac~in- r" . ii d ~ The rross correlations ind ic;. tad. , ':h. ". . t I;ha older ai s nt th. b. . 'nnin; ~" the t'-t ccnsuma...IViT', -". I%X'. TXGN'"FiXP GP VARIABLY" C~ AC". , WT", i' XB' h;=, BXMi, T. ;GTZ% ~HGG~s ANTG)MG GTGCJiL-". H BARHGGA A Thoeie b7 , ". ubmitted to the Graduate school of tho ~g i Aglcultuxal anC Hechnrd. cnl College of Tezaa ln y ~ ~&ia1...

Barbosa, Antonio Stockler

1960-01-01T23:59:59.000Z

128

Magnetostrictive materials and method for improving AC characteristics in same  

DOE Patents [OSTI]

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.

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

2001-08-14T23:59:59.000Z

129

Robust Timing Synchronization for AC-OFDM Based Optical Wireless Communications  

E-Print Network [OSTI]

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...

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

2015-01-01T23:59:59.000Z

130

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

E-Print Network [OSTI]

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

Handy, Todd C.

131

THE ACS NEARBY GALAXY SURVEY TREASURY. III. CEPHEIDS IN THE OUTER DISK OF M81  

SciTech Connect (OSTI)

The ACS Nearby Galaxy Survey Treasury (ANGST) has acquired deep ACS imaging of a field in the outer disk of the large spiral galaxy M81. These data were obtained over a total of 20 Hubble Space Telescope orbits, providing a baseline long enough to reliably identify Cepheid variable stars in the field. Fundamental mode and first overtone types have been distinguished through comparative fits with corresponding Cepheid light curve templates derived from principal component analysis of confirmed Cepheids in the Large Magellanic Cloud (LMC), Small Magellanic Cloud, and Milky Way. A distance modulus of 27.78 {+-} 0.05 {sub r} {+-} 0.14 {sub s} with a corresponding distance of 3.60 {+-} 0.23 Mpc has been calculated from a sample of 11 fundamental mode and two first overtone Cepheids (assuming an LMC distance modulus of {mu}{sub LMC} = 18.41 {+-} 0.10 {sub r} {+-} 0.13 {sub s})

McCommas, Les P.; Williams, Benjamin F.; Dalcanton, Julianne J.; Davis, Matthew R. [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Yoachim, Peter [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States); Dolphin, Andrew E. [Raytheon Corporation, 870 Winter Street Waltham, MA 02451 (United States)], E-mail: lmccomma@astro.washington.edu, E-mail: jd@astro.washington.edu, E-mail: ben@astro.washington.edu, E-mail: mrdavis@astro.washington.edu, E-mail: yoachim@astro.as.utexas.edu, E-mail: adolphin@ratheon.com

2009-06-15T23:59:59.000Z

132

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

133

EXTENSION OF THE MAXIMUM POWER REGION OF DOUBLY-SALIENT VARIABLE RELUCTANCE MOTORS  

E-Print Network [OSTI]

-Salient Variable Reluctance Motors (DSVRM) has been investigated and developed for variable-speed drives during, variable-frequency generators, wind wheels, machine tools, etc.). In these applications, it is generally necessary to operate in a regime of a high speed ux-weakening (zone of maximum constant power), for a better

Paris-Sud XI, Université de

134

www.strath.ac.uk THIS IS YOUR  

E-Print Network [OSTI]

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

Mottram, Nigel

135

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

136

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

E-Print Network [OSTI]

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

Painter, Kevin

137

EXPERIMENTAL STUDY OF ELECTROLYTE DEPENDENCE OF AC ELECTROOSMOTIC PUMPS  

E-Print Network [OSTI]

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

Bazant, Martin Z.

138

A Generic Space-Time-Frequency Correlation Model and Its Corresponding Simulation Model for Narrowband MIMO Channels  

E-Print Network [OSTI]

A Generic Space-Time-Frequency Correlation Model and Its Corresponding Simulation Model.Laurenson d9ed. ac. uk Keyword: Wireless channels, NIIMO, STF correlation, deterministic simulation model theoretical reference model, a deterministic simulation model is then proposed and its 3-D STF correlation

Wang, Cheng-Xiang

139

High frequency reference electrode  

DOE Patents [OSTI]

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.

Kronberg, J.W.

1994-05-31T23:59:59.000Z

140

Research by BNL investigators was performed under the auspices of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886.  

E-Print Network [OSTI]

of Energy under Contract No. DE-AC02-98CH10886. BNL-63565 THE PHOTOCHEMICAL FORMATION OF OZONE: RESULTS FROM UV measurements from an Eppley radiometer. For j(NO2) levels greater than 0.005 s-1 the gross O3 production rate observed in the air masses passing the site averaged 38 ppbvh-1 , but were highly variable

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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141

Self isolating high frequency saturable reactor  

DOE Patents [OSTI]

The present invention discloses a saturable reactor and a method for decoupling the interwinding capacitance from the frequency limitations of the reactor so that the equivalent electrical circuit of the saturable reactor comprises a variable inductor. The saturable reactor comprises a plurality of physically symmetrical magnetic cores with closed loop magnetic paths and a novel method of wiring a control winding and a RF winding. The present invention additionally discloses a matching network and method for matching the impedances of a RF generator to a load. The matching network comprises a matching transformer and a saturable reactor.

Moore, James A. (Powell, TN)

1998-06-23T23:59:59.000Z

142

AN "AC INDUCTOR" BASED GRID CONNECTED INVERTER  

E-Print Network [OSTI]

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

143

ACS Installation During SM3B Introduction  

E-Print Network [OSTI]

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

Sirianni, Marco

144

Appendix AC Exceptions to Delegated Purchasing Authority  

E-Print Network [OSTI]

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

Dyer, Bill

145

Physics and contentswww.manchester.ac.uk  

E-Print Network [OSTI]

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

146

Understanding Biomass Feedstock Variability  

SciTech Connect (OSTI)

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.

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

2013-01-01T23:59:59.000Z

147

Understanding Biomass Feedstock Variability  

SciTech Connect (OSTI)

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.

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

2013-01-01T23:59:59.000Z

148

Grid regulation services for energy storage devices based on grid frequency  

DOE Patents [OSTI]

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).

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

2014-04-15T23:59:59.000Z

149

Grid regulation services for energy storage devices based on grid frequency  

DOE Patents [OSTI]

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).

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

2013-07-02T23:59:59.000Z

150

Seasonal Forecasting of Extreme Wind and Precipitation Frequencies in Europe  

E-Print Network [OSTI]

Seasonal Forecasting of Extreme Wind and Precipitation Frequencies in Europe Matthew J. Swann;Abstract Flood and wind damage to property and livelihoods resulting from extreme precipitation events variability of these extreme events can be closely related to the large-scale atmospheric circulation

Feigon, Brooke

151

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

E-Print Network [OSTI]

sources (e.g., photovoltaics, wind, and fuel cells) to stand-alone loads or the utility. The advantages of these topologies include soft switching at turn-on and turn-off of all the semiconductor devices, exclusion of short-life electrolytic capacitors...

Keyhani, Hamidreza

2014-01-08T23:59:59.000Z

152

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

E-Print Network [OSTI]

and the development of new grid systems like HVDC transmission lines. The new solution proposed needs to incorporate methods for the renewable sources to receive power for monitoring and control, during periods of zero production. This calls for a power converter...

Essakiappan, Somasundaram

2011-08-08T23:59:59.000Z

153

Noise-induced dephasing of an ac-driven Josephson junction  

E-Print Network [OSTI]

We consider phase-locked dynamics of a Josephson junction driven by finite-spectral-linewidth ac current. By means of a transformation, the effect of frequency fluctuations is reduced to an effective additive noise, the corresponding (large) dephasing time being determined, in the logarithmic approximation, by the Kramers' expression for the lifetime. For sufficiently small values of the drive's amplitude, direct numerical simulations show agreement of the dependence of the dephasing activation energy on the ac-drive's spectral linewidth and amplitude with analytical predictions. Solving the corresponding Fokker-Planck equation analytically, we find a universal dependence of a critical value of the effective phase-diffusion parameter on the drive's amplitude at a point of a sharp transition from the phase-locked state to an unlocked one. For large values of the drive amplitude, saturation and subsequent decrease of the activation energy are revealed by simulations, which cannot be accounted for by the perturbative analysis. The same new effect is found for a previously studied case of ac-driven Josephson junctions with intrinsic thermal noise. The work was performed in the framework of a cooperation agreement between Consiglio Nazionale di Ricerca (Italy) and the Israeli Ministry of Science and Technology.

Giovanni Filatrella; Boris A. Malomed; Sergio Pagano

2002-03-28T23:59:59.000Z

154

Frequency-dependent electrostatic actuation in microfluidic MEMS.  

SciTech Connect (OSTI)

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.

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

2003-09-01T23:59:59.000Z

155

Frequency doubling crystals  

DOE Patents [OSTI]

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.

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

1989-01-01T23:59:59.000Z

156

Frequency mixing crystal  

DOE Patents [OSTI]

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.

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

1992-01-01T23:59:59.000Z

157

THE ACS NEARBY GALAXY SURVEY TREASURY  

SciTech Connect (OSTI)

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

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

2009-07-15T23:59:59.000Z

158

Direct amplitude detuning measurement with ac dipole  

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

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

White, S.; Maclean, E.; Tomás, R.

2013-07-01T23:59:59.000Z

159

Effect of Microwave Frequency on Hydrothermal Synthesis of Nanocrystalline Tetragonal Barium Titanate  

E-Print Network [OSTI]

Effect of Microwave Frequency on Hydrothermal Synthesis of Nanocrystalline Tetragonal Barium) with particle sizes ranging from 30 to 100 nm were synthesized via microwave-hydrothermal routes at various, but increased gradually with extended aging time in variable frequency (3-5.5 GHz to 1 s) processing

Dutta, Prabir K.

160

Detectable Changes in the Frequency of Temperature Extremes SIMONE MORAK AND GABRIELE C. HEGERL  

E-Print Network [OSTI]

Detectable Changes in the Frequency of Temperature Extremes SIMONE MORAK AND GABRIELE C. HEGERL of hot and cold extremes over land can be explained by climate variability or whether they show a detectable response to external influences. The authors analyze changes in the frequency of moderate-to-extreme

Hegerl, Gabriele Clarissa "Gabi"

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Long-Term Wind Power Variability  

SciTech Connect (OSTI)

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.

Wan, Y. H.

2012-01-01T23:59:59.000Z

162

Frequency locking in the injection-locked frequency divider equation  

E-Print Network [OSTI]

We consider a model for the injection-locked frequency divider, and study analytically the locking onto rational multiples of the driving frequency. We provide explicit formulae for the width of the plateaux appearing in the devil's staircase structure of the lockings, and in particular show that the largest plateaux correspond to even integer values for the ratio of the frequency of the driving signal to the frequency of the output signal. Our results prove the experimental and numerical results available in the literature.

Bartuccelli, Michele V; Gentile, Guido

2008-01-01T23:59:59.000Z

163

ac losses: Topics by E-print Network  

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

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

164

www.sheffield.ac.uk/careers Develop Your  

E-Print Network [OSTI]

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

Martin, Stephen John

165

Light beam frequency comb generator  

DOE Patents [OSTI]

A light beam frequency comb generator uses an acousto-optic modulator to generate a plurality of light beams with frequencies which are uniformly separated and possess common noise and drift characteristics. A well collimated monochromatic input light beam is passed through this modulator to produce a set of both frequency shifted and unshifted optical beams. An optical system directs one or more frequency shifted beams along a path which is parallel to the path of the input light beam such that the frequency shifted beams are made incident on the modulator proximate to but separated from the point of incidence of the input light beam. After the beam is thus returned to and passed through the modulator repeatedly, a plurality of mutually parallel beams are generated which are frequency-shifted different numbers of times and possess common noise and drift characteristics.

Priatko, Gordon J. (Cupertino, CA); Kaskey, Jeffrey A. (Livermore, CA)

1992-01-01T23:59:59.000Z

166

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

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

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

167

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

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

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

168

E-Print Network 3.0 - ac systems Sample Search Results  

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

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

169

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

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

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

170

Variable Crop Share Leases.  

E-Print Network [OSTI]

)OC lAL45.7 173 1. 1224 Texas Agricultural Extension Service The Texas A&M University System Daniel C. Pfannstiel,Director colleg e Station, Texas / f , ' '~ :';,; ,,: ''': ~ " k , -~. _Variable _Crop Share _Leases ... Marvin... Sartin and Ray Sammons* Renting or leasing farmland is part of many modern farming operations and increases average farm size in U. S. agriculture. Economies of size are vitally import ant to farm operations as they strive to cope with the continuous...

Sartin, Marvin; Sammons, Ray

1980-01-01T23:59:59.000Z

171

Variable depth core sampler  

DOE Patents [OSTI]

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.

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

1996-02-20T23:59:59.000Z

172

3, 19151942, 2006 Longterm variability  

E-Print Network [OSTI]

, 690041, Radio st., 7, Russia, 2 Delft University of Technology, Faculty of Civil Engineering, Section of about 2­3 yr and 6­8 yr that are ac- companied by statistically significant changes in such monthly, there is uncertainty in the question how climatic systems evolve. The potential reliability of climate models can

Paris-Sud XI, Université de

173

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

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

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

174

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

Energy Savers [EERE]

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

175

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

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

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

176

IS ACTIVE REGION CORE VARIABILITY AGE DEPENDENT?  

SciTech Connect (OSTI)

The presence of both steady and transient loops in active region cores has been reported from soft X-ray and extreme-ultraviolet observations of the solar corona. The relationship between the different loop populations, however, remains an open question. We present an investigation of the short-term variability of loops in the core of two active regions in the context of their long-term evolution. We take advantage of the nearly full Sun observations of STEREO and Solar Dynamics Observatory spacecraft to track these active regions as they rotate around the Sun multiple times. We then diagnose the variability of the active region cores at several instances of their lifetime using EIS/Hinode spectral capabilities. We inspect a broad range of temperatures, including for the first time spatially and temporally resolved images of Ca XIV and Ca XV lines. We find that the active region cores become fainter and steadier with time. The significant emission measure at high temperatures that is not correlated with a comparable increase at low temperatures suggests that high-frequency heating is viable. The presence, however, during the early stages, of an enhanced emission measure in the ''hot'' (3.0-4.5 MK) and ''cool'' (0.6-0.9 MK) components suggests that low-frequency heating also plays a significant role. Our results explain why there have been recent studies supporting both heating scenarios.

Ugarte-Urra, Ignacio [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

2012-12-10T23:59:59.000Z

177

Acoustic resonance frequency locked photoacoustic spectrometer  

DOE Patents [OSTI]

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.

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

2003-09-09T23:59:59.000Z

178

Stabilized radio-frequency quadrupole  

DOE Patents [OSTI]

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.

Lancaster, H.D.; Fugitt, J.A.; Howard, D.R.

1982-09-29T23:59:59.000Z

179

SECURING RADIO FREQUENCY IDENTIFICATION (RFID)  

E-Print Network [OSTI]

business process for an organization; as a result, the security risks for RFID systems and the controls for an organization; as a result, the security risks for RFID systems and the controls available to address themMay 2007 SECURING RADIO FREQUENCY IDENTIFICATION (RFID) SYSTEMS SECURING RADIO FREQUENCY

180

Method and apparatus for pulse width modulation control of an AC induction motor  

DOE Patents [OSTI]

An inverter is connected between a source of DC power and a three-phase AC induction motor, and a micro-processor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .THETA., where .THETA. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands of electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.

Geppert, Steven (Bloomfield Hills, MI); Slicker, James M. (Union Lake, MI)

1984-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

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

182

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

E-Print Network [OSTI]

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

Aickelin, Uwe

183

IT Services go.warwick.ac.uk/whatsnew2010  

E-Print Network [OSTI]

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

Davies, Christopher

184

Electrostatic coalescence system with independent AC and DC hydrophilic electrodes  

DOE Patents [OSTI]

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

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

1981-01-01T23:59:59.000Z

185

A Distributed Generation Control Architecture for Islanded AC Microgrids  

E-Print Network [OSTI]

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

Dominguez-Garcia, Alejandro

186

Analysis of Heart Rate Variability Using Time-Varying Filtering of Heart Transplanted Patients  

E-Print Network [OSTI]

Analysis of Heart Rate Variability Using Time-Varying Filtering of Heart Transplanted Patients the heart rate variability (HRV), obtained by using the time-varying integral pulse frequency modulation (TVIPFM) which is well adapted to the exercise stress testing. We consider that the mean heart period

Paris-Sud XI, Université de

187

Florida Current transport variability: An analysis of annual and longer-period signals  

E-Print Network [OSTI]

n f o Article history: Received 23 June 2009 Received in revised form 9 December 2009 Accepted 7 scale variability given the strong higher frequency energy present. The annual cycle represents less variability. Comparison of the Florida Current, NAO and wind stress curl records shows that a recently

188

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

E-Print Network [OSTI]

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

Squicciarini, Anna Cinzia

189

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

E-Print Network [OSTI]

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

Tanaka, Jiro

190

PHP: Constructs and Variables Introduction  

E-Print Network [OSTI]

PHP: Constructs and Variables Introduction This document describes: 1. the syntax and types of variables, 2. PHP control structures (i.e., conditionals and loops), 3. mixed-mode processing, 4. how to use one script from within another, 5. how to define and use functions, 6. global variables in PHP, 7

Vander Zanden, Brad

191

Blazar Variability and Evolution in the GeV Regime  

E-Print Network [OSTI]

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.

Tsujimoto, S; Nishijima, K; Kodani, K

2015-01-01T23:59:59.000Z

192

AUTO ID FUTURE - FREQUENCY AGNOSTIC  

E-Print Network [OSTI]

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 ...

DATTA, SHOUMEN

193

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 ...

194

Frequency regulator for synchronous generators  

DOE Patents [OSTI]

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.

Karlicek, R.F.

1982-08-10T23:59:59.000Z

195

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

SciTech Connect (OSTI)

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.

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

1982-09-01T23:59:59.000Z

196

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

E-Print Network [OSTI]

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

Zhang, Yuemin

1993-01-01T23:59:59.000Z

197

DC, AC and advanced EV propulsion systems  

SciTech Connect (OSTI)

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

O'Neil, W.

1983-08-01T23:59:59.000Z

198

Optimal design of AC filter circuits in HVDC converter stations  

SciTech Connect (OSTI)

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

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

1995-12-31T23:59:59.000Z

199

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

SciTech Connect (OSTI)

The contactless surface acoustic wave technique is implemented to probe the high-frequency conductivity of a high-mobility p-Ge/GeSi quantum well structure in the regime of integer quantum Hall effect (IQHE) at temperatures 0.3–5.8 K and magnetic fields up to 18 T. It is shown that, in the IQHE regime at the minima of conductivity, holes are localized and ac conductivity is of hopping nature and can be described within the “two-site” model. The analysis of the temperature and magnetic-field-orientation dependence of the ac conductivity at odd filing factors enables us to determine the effective hole g-factor, |g{sub zz}|?4.5. It is shown that the in-plane component of the magnetic field leads to a decrease in the g-factor as well as increase in the cyclotron mass, which is explained by orbital effects in the complex valence band of germanium.

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

2014-08-20T23:59:59.000Z

200

Contract Number: DE-AC05-76RL01830 Modification M705  

E-Print Network [OSTI]

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

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

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

E-Print Network [OSTI]

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...

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

2013-01-01T23:59:59.000Z

202

Total compensation of line-side switching harmonics in converter-fed ac locomotives  

SciTech Connect (OSTI)

PWM controlled line-side converters of modern ac traction locomotives inject harmonic currents into the feeding overhead line. This causes problems of electromagnetic interference. Passive or active filters are usually provided for a partial reduction of the line harmonics. A novel and superior approach employs a switched electronic compensator. It generates an exact replica of the harmonic current, feeding it to the high-voltage transformer to produce a harmonic counter MMF. The transformer main flux is then forced to be sinusoidal, and so is the induced voltage in the primary. The line current, being low-pass filtered by the transformer leakage inductance, assumes a pure sinusoidal waveform. The compensator operates in the low switching frequency range of the main power converters. Its installed power is only 1% of the traction power. Operation, control, and design considerations are described. Results from laboratory tests at full power level are presented.

Krah, J.O.; Holtz, J. [Univ. of Wuppertal (Germany)] [Univ. of Wuppertal (Germany)

1995-11-01T23:59:59.000Z

203

ac linear positioning: Topics by E-print Network  

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

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

204

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

E-Print Network [OSTI]

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

Macdonald, James Ross

205

acs morphological study: Topics by E-print Network  

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

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

206

10.1071/SR10009_AC1 CSIRO 20102  

E-Print Network [OSTI]

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

Lehmann, Johannes

207

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

E-Print Network [OSTI]

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

Bahk, Saewoong

208

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

E-Print Network [OSTI]

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

Aickelin, Uwe

209

acs presspac: Topics by E-print Network  

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

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

210

ac microsized gliding: Topics by E-print Network  

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

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

211

acs evidence based: Topics by E-print Network  

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

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

212

ac surface photovoltage: Topics by E-print Network  

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

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

213

acute cholecystitis ac: Topics by E-print Network  

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

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

214

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

215

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

E-Print Network [OSTI]

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

Hickman, Mark

216

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

E-Print Network [OSTI]

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

Guo, Zaoyang

217

University Policy No.: AC1145 Classification: Academic and Students  

E-Print Network [OSTI]

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

Victoria, University of

218

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

E-Print Network [OSTI]

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

Aickelin, Uwe

219

ac magnetic field: Topics by E-print Network  

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

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

220

ac magnetic fields: Topics by E-print Network  

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

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

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

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

E-Print Network [OSTI]

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

Banaji,. Murad

222

JOURNAL OF STRUCTURAL ENGINEERING / MAY 2001 / 527 APPARENT PERIODS OF A BUILDING. II: TIME-FREQUENCY ANALYSIS  

E-Print Network [OSTI]

of a two-part paper, the analysis of the apparent frequency of a seven-story reinforced-concrete hotel. The results also suggest ``self healing'' believed to result from settlement of the soil with time and dynamic compaction from aftershock shaking. Implications of such high variability of the system frequency

Southern California, University of

223

Location and prediction of storms from measurement of atmospherics at different frequencies  

E-Print Network [OSTI]

the Earth?, Proc. I.R.E., vol. 19, p. 145;: January, 1931. 75. L. W. Austin, "Radio Atmospheric Disturbances and Solar Ac? tivity?, Proc. I.R.E., vol. 15, pp. 837-842; October, 1927. 76. J. K. McNeely and P. J. Konkle, ?Locating Radio Interference... atmospherics from a distant thun? derstorm, with his receiver tuned to 14*6 meters* Many investiga? tions2' C A 8# 9* n * 20* 26' 27* 28 have shown that the atmospher- 29 30ics increase as the frequency is decreased* Mr. Harold Norinder* * and Messers* B* V...

Canterbury, Samuel Luther

1945-01-01T23:59:59.000Z

224

High frequency and high wavenumber solar oscillations  

E-Print Network [OSTI]

We determine the frequencies of solar oscillations covering a wide range of degree (100< l <4000) and frequency (1.5 <\

H. M. Antia; Sarbani Basu

1999-02-10T23:59:59.000Z

225

Sum Frequency Generation for Surface Vibrational Spectroscopy...  

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

Sum Frequency Generation for Surface Vibrational Spectroscopy Sum Frequency Generation for Surface Vibrational Spectroscopy This customized SFG-VS spectrometer incorporates unique...

226

Development of an AC Module System: Final Technical Report  

SciTech Connect (OSTI)

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.

Suparna Kadam; Miles Russell

2012-06-15T23:59:59.000Z

227

Adjustable Speed AC Motor Drives-Applications Problems  

E-Print Network [OSTI]

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

Enjeti, P.

228

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

DOE Patents [OSTI]

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.

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

1998-01-01T23:59:59.000Z

229

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

DOE Patents [OSTI]

Method and apparatus ar disclosed 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. 4 figs.

Dawson, J.M.; Mori, W.B.; Lai, C.H.; Katsouleas, T.C.

1998-07-14T23:59:59.000Z

230

Heart Rate Variability Analysis Using Threshold of Wavelet Package Coefficients  

E-Print Network [OSTI]

In this paper, a new efficient feature extraction method based on the adaptive threshold of wavelet package coefficients is presented. This paper especially deals with the assessment of autonomic nervous system using the background variation of the signal Heart Rate Variability HRV extracted from the wavelet package coefficients. The application of a wavelet package transform allows us to obtain a time-frequency representation of the signal, which provides better insight in the frequency distribution of the signal with time. A 6 level decomposition of HRV was achieved with db4 as mother wavelet, and the above two bands LF and HF were combined in 12 specialized frequencies sub-bands obtained in wavelet package transform. Features extracted from these coefficients can efficiently represent the characteristics of the original signal. ANOVA statistical test is used for the evaluation of proposed algorithm.

Kheder, G; Massoued, M Ben; Samet, M

2009-01-01T23:59:59.000Z

231

WECC Variable Generation Planning Reference Book: Appendices  

SciTech Connect (OSTI)

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.

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

2013-05-13T23:59:59.000Z

232

Selection automatique de variables pertinentes  

E-Print Network [OSTI]

S´election automatique de variables pertinentes Vers la d´ecouverte de nouvelles modalit´es sensori-motrices corr´elations entre ses variables sensori-motrices afin d'apprendre `a r´esoudre sa t^ache d

Boyer, Edmond

233

Intelligent Radio Frequency (RF) Monitoring  

E-Print Network [OSTI]

? Intelligent Radio Frequency (RF) Monitoring ? 2009 Armstrong International, Inc. www.armstronginternational.com 2 ?Expect many enjoyable experiences!? David M. Armstrong Present Process Challenges ? Identifying a failure ? Procedure.... Armstrong Steam Trap Challenges ? Identifying a failure ? Manpower ? Location ? Magnitude of failure ? Energy loss ? Loss of heat transfer ? Justification for repair ? ?Speed of Implementation? ? Environmental concerns Manpower Location 4...

Kimbrough, B.

234

Frequency agile optical parametric oscillator  

DOE Patents [OSTI]

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.

Velsko, Stephan P. (Livermore, CA)

1998-01-01T23:59:59.000Z

235

Frequency agile optical parametric oscillator  

DOE Patents [OSTI]

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.

Velsko, S.P.

1998-11-24T23:59:59.000Z

236

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

SciTech Connect (OSTI)

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.

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

2013-02-26T23:59:59.000Z

237

Installation considerations for IGBT AC drives  

SciTech Connect (OSTI)

In the last four years, Adjustable Speed ac Drive (ASD) manufacturers have migrated from Bipolar Junction Transistor (BJT) semiconductors to Insulated Gate Bipolar Transistors (IGBTs) as the preferred Output switching device. The advantage of IGBTs over BJTs is that device rise and fall time switching capability is 5 - 10 times faster, resulting in lower device switching loss and a more efficient drive. However, for a similar motor cable length as the BJT drive, the faster output voltage risetime of the IGBT drive may increase the dielectric voltage stress on the motor and cable due to a phenomenon called reflected wave. Faster output dv/dt transitions of IGBT drives also increase the possibility for phenomenon such as increased Common Mode (CM) electrical noise, Electromagnetic Interference (EMI) problems and increased capacitive cable charging current problems. Also, recent experience suggests any Pulse Width Modulated (PWM) drive with a steep fronted output voltage wave form may increase motor shaft voltage and lead to a bearing current phenomenon known as fluting. This paper provides a basic understanding of these issues, as well as solutions, to insure a successful drive system installation.

Skibinski, G.L.

1997-06-01T23:59:59.000Z

238

DE-AC05-00OR22725 Section B--Page 1 of 7 DE-AC05-00OR22725  

E-Print Network [OSTI]

.......................................................................... 5 #12;DE-AC05-00OR22725 Section B--Page 2 of 7 DE-AC05-000R22725 Modification No. 760 Section B Blank Page #12;DE-AC05-00OR22725 Section B--Page 3 of 7 DE-AC05-000R22725 Modification No. 760 Section B of 7 DE-AC05-000R22725 Modification No. 760 Section B 4) $267,518 for the project entitled "4500 Area

239

BROAD ABSORPTION LINE VARIABILITY ON MULTI-YEAR TIMESCALES IN A LARGE QUASAR SAMPLE  

SciTech Connect (OSTI)

We present a detailed investigation of the variability of 428 C IV and 235 Si IV broad absorption line (BAL) troughs identified in multi-epoch observations of 291 quasars by the Sloan Digital Sky Survey-I/II/III. These observations primarily sample rest-frame timescales of 1-3.7 yr over which significant rearrangement of the BAL wind is expected. We derive a number of observational results on, e.g., the frequency of BAL variability, the velocity range over which BAL variability occurs, the primary observed form of BAL-trough variability, the dependence of BAL variability upon timescale, the frequency of BAL strengthening versus weakening, correlations between BAL variability and BAL-trough profiles, relations between C IV and Si IV BAL variability, coordinated multi-trough variability, and BAL variations as a function of quasar properties. We assess implications of these observational results for quasar winds. Our results support models where most BAL absorption is formed within an order-of-magnitude of the wind-launching radius, although a significant minority of BAL troughs may arise on larger scales. We estimate an average lifetime for a BAL trough along our line-of-sight of a few thousand years. BAL disappearance and emergence events appear to be extremes of general BAL variability, rather than being qualitatively distinct phenomena. We derive the parameters of a random-walk model for BAL EW variability, finding that this model can acceptably describe some key aspects of EW variability. The coordinated trough variability of BAL quasars with multiple troughs suggests that changes in 'shielding gas' may play a significant role in driving general BAL variability.

Filiz Ak, N.; Brandt, W. N.; Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario, M3J 1P3 (Canada); Anderson, S. F. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Hamann, F. [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States); Lundgren, B. F. [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Pâris, I. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, P. [Universite Paris 6, Institut d'Astrophysique de Paris, 75014, Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 92420 (United States); Shen, Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-51, Cambridge, MA 02138 (United States); York, Don, E-mail: nfilizak@astro.psu.edu [The University of Chicago, Department of Astronomy and Astrophysics, Chicago, IL 60637 (United States)

2013-11-10T23:59:59.000Z

240

Quantum information with modular variables  

E-Print Network [OSTI]

We introduce a novel strategy, based on the use of modular variables, to encode and deterministically process quantum information using states described by continuous variables. Our formalism leads to a general recipe to adapt existing quantum information protocols, originally formulated for finite dimensional quantum systems, to infinite dimensional systems described by continuous variables. This is achieved by using non unitary and non-gaussian operators, obtained from the superposition of gaussian gates, together with adaptative manipulations in qubit systems defined in infinite dimensional Hilbert spaces. We describe in details the realization of single and two qubit gates and briefly discuss their implementation in a quantum optical set-up.

A. Ketterer; S. P. Walborn; A. Keller; T. Coudreau; P. Milman

2014-06-24T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

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

SciTech Connect (OSTI)

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.

Liu, Yong [The University of Tennessee, Knoxville; Gracia, Jose R [ORNL; Hadley, Stanton W [ORNL; Liu, Yilu [ORNL

2013-12-01T23:59:59.000Z

242

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

SciTech Connect (OSTI)

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.

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)

2014-10-28T23:59:59.000Z

243

Abstract--Heart rate variability (HRV) is frequently used to measure autonomic nervous system (ANS) activity. However,  

E-Print Network [OSTI]

1 of 4 Abstract--Heart rate variability (HRV) is frequently used to measure autonomic nervous frequency (HF) ratio with little change in mean heart rate. Results suggest that nicotine affects both components may yield erroneous results. Keywords--Autonomic regulation, heart rate variability, Lomb

244

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

E-Print Network [OSTI]

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.

Alison Klesman; Vicki Sarajedini

2007-05-07T23:59:59.000Z

245

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

SciTech Connect (OSTI)

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.

Metlov, Konstantin L., E-mail: metlov@fti.dn.ua [Donetsk Institute for Physics and Technology NAS, Donetsk 83114 (Ukraine)

2013-12-14T23:59:59.000Z

246

Computer-controlled, variable-frequency power supply for driving multipole ion guides  

E-Print Network [OSTI]

in a parallel geometry within an insulating spacer. rf waveforms, which are 180° out of phase with respect parameters, including ge- ometries, pressures, aperture dimensions, voltages applied to electrostatic

Zare, Richard N.

247

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

E-Print Network [OSTI]

the support and guidance of Dr. Alexis Lugo-Fern?ndez at MS. Thanks also goes to the researchers I?ve met throughout the course of the EGOM project, namely Dr. Robert Leben, whose sea surface height product I?ve used extensively in this thesis. I want... O?Hern, and my clasmates Laura Rubiano-G?mez and Chrisy Wiederwohl, for their friendship, and for not leting me spend too much time at the O&M. Above al, I want to thank my family for their encouragement and support of my pasions. I am fortunate...

Cole, Kelly Lynne

2009-05-15T23:59:59.000Z

248

Variable metric conjugate gradient methods  

SciTech Connect (OSTI)

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

Barth, T.; Manteuffel, T.

1994-07-01T23:59:59.000Z

249

E-Print Network 3.0 - ac power distribution Sample Search Results  

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

Ray Summary: Capacitor Bias - T Figure 4 - AC Distribution Using a Bias-T Advantages of Power Distribution Using Bias... . In the case of AC power distribution with bias-T...

250

DE-AC02-76SF00515 Apr2007/Rev 1  

E-Print Network [OSTI]

DE-AC02-76SF00515 Appendix B Apr2007/Rev 1 FY 2007 Contractor Performance Evaluation and Measurement Plan for Management and Operations ofthe Stanford Linear Accelerator Center J-B-i #12;DE-AC02

Wechsler, Risa H.

251

Superconducting shielded core reactor with reduced AC losses  

DOE Patents [OSTI]

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.

Cha, Yung S.; Hull, John R.

2006-04-04T23:59:59.000Z

252

Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants  

E-Print Network [OSTI]

presents a simulation model of a wind power plant based on a MW-level variable speed wind turbineAncillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants Weihao Hu with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory

Chen, Zhe

253

Atmospheric circulation and cyclone frequency variations linked to the primary modes of Greenland snow accumulation  

E-Print Network [OSTI]

Atmospheric circulation and cyclone frequency variations linked to the primary modes of Greenland from 34 Greenland firn cores, extending from 1982 to 1996, are used to identify spatial accumulation component, representing west-central Greenland accumulation, is correlated to NAO variability, having

Howat, Ian M.

254

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

255

A coupled BEM and energy flow method for mid-high frequency internal acoustic  

E-Print Network [OSTI]

formalism whereas the SEA formalism is based on global energies of finite subsystems. This model has been using four energy variables: the total energy as well as the Lagrangian energy density, the activeA coupled BEM and energy flow method for mid-high frequency internal acoustic Sbastien BESSET, M

Paris-Sud XI, Université de

256

Sarah.Glynn@ed.ac.uk April 2008 Liberalising Islam: creating Brits of the Islamic Persuasion  

E-Print Network [OSTI]

.Glynn@ed.ac.uk April 2008 1 Liberalising Islam: creating Brits of the Islamic Persuasion In common with other

257

Contract No. DE-AC05-76RL01830 Modification M943  

E-Print Network [OSTI]

Contract No. DE-AC05-76RL01830 Modification M943 SECTION J APPENDIX A ADVANCE UNDERSTANDINGS ON HUMAN RESOURCES COST Applicable to the Operation of PACIFIC NORTHWEST NATIONAL LABORATORY Contract No. DE-AC05-76RL01830 #12;Contract No. DE-AC05-76RL01830 Modification M943 J-A-1 Table of Contents

258

Contract Number: DE-AC05-76RL01830 Modification M957  

E-Print Network [OSTI]

Contract Number: DE-AC05-76RL01830 Modification M957 APPENDIX E STANDARDS OF PERFORMANCE-BASED FEE OF THE PACIFIC NORTHWEST NATIONAL LABORATORY #12;Contract Number: DE-AC05-76RL01830 Modification M957 APPENDIX E FOR MANAGEMENT AND OPERATIONS OF THE PACIFIC NORTHWEST NATIONAL LABORATORY #12;Contract Number: DE-AC05-76RL01830

259

(mercury.yukawa.kyoto-u.ac.jp)ssh Permission denied (publickey).  

E-Print Network [OSTI]

SSH Q&A (mercury.yukawa.kyoto-u.ac.jp)ssh Permission denied (publickey). (1) ID ID ID (2) ssh -i () ssh -i $HOME/.ssh/id_yitp_rsa (UID)@mercury.yukawa.kyoto-u.ac.jp (3) (1)(2) Permission denied support@yukawa.kyoto-u.ac.jp (mercury

Shimizu, Akira

260

Frequency Control Performance Measurement and Requirements  

E-Print Network [OSTI]

changes in dispatch to follow load, implement interchangerequired for load frequency regulation, it follows that afollows [4]: “System frequency deviation and the resulting time error indicated the total imbalance of generation and load

Illian, Howard F.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Frequency Synthesis in Wireless and Wireline Systems  

E-Print Network [OSTI]

First, a frequency synthesizer for IEEE 802.15.4 / ZigBee transceiver applications that employs dynamic True Single Phase Clocking (TSPC) circuits in its frequency dividers is presented and through the analysis and measurement results...

Turker, Didem 1981-

2010-12-06T23:59:59.000Z

262

Frequency domain design of interval controller  

E-Print Network [OSTI]

significant role in the analysis and design of interval systems. Its external properties are also discussed. The image set approach & frequency domain criteria can be used to calculate the IP stability margin. The frequency domain criteria are used...

Park, Wunyong

1993-01-01T23:59:59.000Z

263

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

E-Print Network [OSTI]

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.

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

2014-09-04T23:59:59.000Z

264

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

SciTech Connect (OSTI)

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.

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

1986-10-01T23:59:59.000Z

265

The ACS LCID Project: data reduction strategy  

E-Print Network [OSTI]

During Cycle 14 a total of 113 HST orbits were secured to observe five isolated dwarf galaxies, namely Tucana, LGS3, LeoA, IC1613, and Cetus. The aim of the project is a full characterization of the stellar content of these galaxies, in term of their SFH, radial distributions, halo populations and variable stars. Deep (V~29) F475W, F814W data allowed us to fully sample all the evolutionary phases from the tip of the Red Giant Branch (RGB) to well below the old Main Sequence Turnoff (MSTO). Here we describe the observational design, and the reduction and calibration strategy adopted. A comparison of the results obtained using two different packages, ALLFRAME and Dolphot, is presented.

M. Monelli

2007-05-18T23:59:59.000Z

266

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

E-Print Network [OSTI]

for Grid-tied Energy Storage System XhaFreh qu, K.J. uneng,grid-tied energy storage systems (ESS) will be voltage to aGrid-tied energy storage system (ESS) is increasingly used

King Jet, TSENG

2013-01-01T23:59:59.000Z

267

Aircraft AC Generators: Hybrid System Modeling and Simulation  

E-Print Network [OSTI]

--Integrated Drive Generators (IDGs) are the main source of electrical power for a number of critical systems1 Aircraft AC Generators: Hybrid System Modeling and Simulation Ashraf Tantawy, Student Member is a difficult task. dq0 models have been developed for design and control of generators, but these models

Koutsoukos, Xenofon D.

268

www.strath.ac.uk/engineering Faculty of Engineering  

E-Print Network [OSTI]

. The Faculty of Engineering wishes to thank all of our industrial partners who offer invaluable opportunitieswww.strath.ac.uk/engineering @StrathEng Faculty of Engineering Scholarships #12;Contents University of Strathclyde | Faculty of Engineering Scholarships Contents02 The Faculty of Engineering provides a wide range

Mottram, Nigel

269

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

E-Print Network [OSTI]

www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Reforming Small Power Systems under Rabindra Nepal and Tooraj Jamasb The pioneering electricity sector reforms in developing Latin American of `successful and comprehensive electricity reforms' in many less-developed countries like Nepal. Nepal's power

Aickelin, Uwe

270

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

E-Print Network [OSTI]

www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Reforming Small Power Systems under Political Nepal and Tooraj Jamasb This paper assesses the electricity sector reforms across small power systems make power sector reform in Nepal and similar small systems a more complex process. As international

Aickelin, Uwe

271

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

E-Print Network [OSTI]

valuation method (CVM) to investigate information effects in the valuation of electricity and waterwww.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Information Effects in Valuation of Electricity and Water Service Attributes Using Contingent Valuation EPRG Working Paper 1127 Cambridge Working

Aickelin, Uwe

272

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

E-Print Network [OSTI]

factors that affect WTP for the attributes considered. Keywords Contingent Valuation Method, Willingnesswww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Information Effects in Valuation of Electricity and Water Service Attributes Using Contingent Valuation EPRG Working Paper 1127 Cambridge Working Paper

Aickelin, Uwe

273

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

E-Print Network [OSTI]

www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY The Economics of the Nord Stream with the construction of the Yamal-Europe pipeline in the 1990s and continued more recently with the Nord Stream west-European clients. The Nord Stream project has been politically controversial since its inception

Aickelin, Uwe

274

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

E-Print Network [OSTI]

www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract The Economics of the Nord Stream Pipeline System M. Reiner We calculate the total cost of building Nord Stream and compare its levelised unit cost of shipping through Nord Stream is clearly lower than using the Ukrainian route and is only

Aickelin, Uwe

275

ACS DIVISION OF POLYMERIC MATERIALS: SCIENCE AND ENGINEERING  

E-Print Network [OSTI]

, interpenetrating polymer networks, IPNs. Other topics included the mechanical and morphological aspects of polymers textbook, "Introduction to Physical Polymer Science," with Wiley, 2004. While in retirement, he remains for Polymer Science and Engineering, and served as Education Chairman. His efforts at ACS have included

Gilchrist, James F.

276

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

E-Print Network [OSTI]

, in the planning and commissioning of equipment, and in site and plant supervision. Engineers require a wide rangeSCHOOL OF ENGINEERING www.abdn.ac.uk/engineering POSTGRADUATE GUIDE #12;MSc Renewable Energy MSc Safety Engineering for Oil & Gas MSc Subsea Engineering MSc Oil & Gas Engineering MSc Project Management

Levi, Ran

277

www.cardiff.ac.uk/ifp International Foundation  

E-Print Network [OSTI]

www.cardiff.ac.uk/ifp International Foundation Programme Business, Engineering, Health & Life Sciences #12;Welcome to the International Foundation Programme at Cardiff University What is the IFP? The International Foundation Programme (IFP) is a one-year academic programme designed to give you the academic

Davies, Christopher

278

1go.warwick.ac.uk/engineering ENGINEERING  

E-Print Network [OSTI]

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'Ã?TRE IS TO SERVE

Davies, Christopher

279

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

E-Print Network [OSTI]

. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise fromwww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Locational-based Coupling of Electricity Markets the effects of varying system characteristics on the magnitude of the locational-based unit commitment

de Gispert, Adrià

280

Carbon Nanotube Field-effect Transistors: AC Performance Capabilities.  

E-Print Network [OSTI]

Carbon Nanotube Field-effect Transistors: AC Performance Capabilities. D.L. Pulfrey, D.L. John-barrier carbon nanotube field-effect transistors are examined via simulations using a self-consistent Schrödinger is known about the DC capabilities of carbon nanotube field-effect transistors [1,2,3], and devices

Pulfrey, David L.

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

www.glasgow.ac.uk/library The University Library  

E-Print Network [OSTI]

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

Guo, Zaoyang

282

POLICY ON CALENDAR SUBMISSIONS University Policy No: AC1120  

E-Print Network [OSTI]

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

Victoria, University of

283

University Policy No.: AC1130 Classification: Academic and Students  

E-Print Network [OSTI]

University Policy No.: AC1130 Classification: Academic and Students Approving Authority: Board Last Editorial Change: Mandated Review: 2018 PURPOSE 1.00 The purpose of this policy is to provide guidance on the establishment and governance of student awards by the university. POLICY 2.00 Student

Victoria, University of

284

ACS WFC CCD Radiation Test: The Radiation Environment  

E-Print Network [OSTI]

of external surfaces by naturally occurring atomic oxygen. CCD detectors are particularly vulnerable to damage damage. A comprehensive discussion of the types of radiation damage known to occur in CCDs is beyond1 ACS WFC CCD Radiation Test: The Radiation Environment Michael R. Jones Space Telescope Science

Sirianni, Marco

285

University Policy No.: AC1110 Classification: Academic and Students  

E-Print Network [OSTI]

other than the university community. DEFINITIONS 2.00 EDUCATIONAL SERVICE CONTRACT means a contract://web.uvic.ca/univsec/pol_pro/pol1000/1002SA.html) 8.00 Approval of an Educational Service Contract will be granted by the Dean andUniversity Policy No.: AC1110 Classification: Academic and Students EDUCATIONAL SERVICE

Victoria, University of

286

2D 3D * iklee)@yonsei.ac.kr  

E-Print Network [OSTI]

1 2012 2D 3D * 0 , 1 , 2 0,2 1 ( 0 skrcjstk, 2 iklee)@yonsei.ac.kr 1 rinthel Science, Yonsei University. 1 Dept. of Information Media, The University of Suwon. 2D 3D . 2D - , 3D (Disparity) 3D . . 1. 3D 3D . 3D 3D [1

Lee, In-Kwon

287

University Policy No.: AC1135 Classification: Academic and Students  

E-Print Network [OSTI]

or graduate certificate or diploma program must have a clearly defined educational objective and rationaleUniversity Policy No.: AC1135 Classification: Academic and Students POLICY FOR THE ESTABLISHMENT Approving Authority: Senate OF CERTIFICATE AND DIPLOMA Effective Date: December/07 PROGRAMS Supersedes: May

Victoria, University of

288

University Policy No.: AC1200 Classification: Academic and Students  

E-Print Network [OSTI]

University Policy No.: AC1200 Classification: Academic and Students GUIDELINES ON CONFLICT be no unfair restrictions on the educational and employment opportunities of all students nor, or applying to be enrolled, in a course or program offered by the University for credit towards

Victoria, University of

289

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

E-Print Network [OSTI]

of the nuclear element of the energy decision process is #12;www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON, energy efficiency, distributed power generation and renewable energy sources. Opponents to nuclear power and Nuclear Power Generation EPRG Working Paper EPRG 0912 John Ash The issue of whether to include nuclear

Aickelin, Uwe

290

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

E-Print Network [OSTI]

www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Nuclear Energy in the Enlarged with with nuclear energy has also increased markedly in recent years. Two contrasting examples of nuclear experience to concerns for Europe's energy security. As citizens in these countries shift to electric heating

Aickelin, Uwe

291

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

E-Print Network [OSTI]

www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Nuclear Energy in the Enlarged European Union of nuclear energy and notes that it has shifted significantly as the European Union has grown from 15 member states to 27. The proportion of member states with nuclear energy experience has increased markedly. Also

Aickelin, Uwe

292

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

E-Print Network [OSTI]

). There are resource shortages already in the nuclear energy industry, and currently the Supplier to the nuclear in existence. The latter problems pose a risk for the Suppliers to operators in the nuclear energy industrywww.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Third Party Nuclear Liability

Aickelin, Uwe

293

FBDEditor: {ldalove, atang34, syjsmk, jbyoo}@konkuk.ac.kr  

E-Print Network [OSTI]

}@konkuk.ac.kr : Programmable Logic Controller (PLC) . Field Programmable Gate Array (FPGA) . PLC Function Controller (PLC) Field Programmable Gate Array (FPGA) . PLC IEC 61131-3 5 (LD: Ladder diagram) . FBD Function Block(FB) . FBD PLC . FPGA Hardware Description Language

294

Efficiency Ratings for the Daiken AC (Americas), Inc.  

E-Print Network [OSTI]

Efficiency Ratings for the Daiken AC (Americas), Inc. Altherma Air-to-Water Source Heat Pump System is used to provide water heating, the EF for that separate water heater shall be used for performance Description Model No. Capacity (tons) Space Heating Space Cooling SEER Water Heating Efficiency

295

Multiple frequency method for operating electrochemical sensors  

DOE Patents [OSTI]

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.

Martin, Louis P. (San Ramon, CA)

2012-05-15T23:59:59.000Z

296

Operating Reserves and Variable Generation  

SciTech Connect (OSTI)

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.

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

2011-08-01T23:59:59.000Z

297

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

E-Print Network [OSTI]

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

Sanders, Seth

298

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

299

Heightened tropical cyclone activity in the North Atlantic: natural variability or  

E-Print Network [OSTI]

relatively stable regimes separated by sharp transitions. Each regime has seen 50% more cyclonesHeightened tropical cyclone activity in the North Atlantic: natural variability or climate trend cyclone and hurricane frequency over the past century in the North Atlantic Ocean have occurred as three

Webster, Peter J.

300

Sensorless Direct Torque Control For Salient Pole PMSM Based on Extended Kalman Filter Fed By AC/DC/AC Converter  

E-Print Network [OSTI]

Sensorless Direct Torque Control For Salient ­ Pole PMSM Based on Extended Kalman Filter Fed By AC is proposed. The Direct Torque Control (DTC) technique for PMSM is receiving increasing attention due on the stochastic intromission, in others words, noise. The PMSM is fed by an indirect power electronic converter

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

The driving frequency effects on the atmospheric pressure corona jet plasmas from low frequency to radio frequency  

SciTech Connect (OSTI)

Lately, the atmospheric pressure jet type corona plasma, which has been typically driven by dc to low frequency (LF: several tens of kHz), is often generated by using radio frequency of 13.56 MHz. Yet, the relationship between the plasma and its driving frequency has seldom been investigated. Hence, in this study, dependence of the atmospheric pressure corona plasma characteristics on the driving frequency was explored experimentally from LF to rf (5 kHz-13.56 MHz). The plasmas generated by the driving frequency under 2 MHz were cylindrical shape of several tens of millimeters long while the 13.56 MHz plasma is spherical and a few millimeters long. As the driving frequency was increased, the plasma length became shortened. At the lower driving frequencies (below 2 MHz), the plasmas existed as positive streamer and negative glow for each half period of the applied voltage, but the discharge was more continuous in time for the 13.56 MHz plasma. It was inferred from the measured I-V curves that the higher driving frequency induced higher discharge currents, and the gas temperature was increased as the driving frequency was increased.

Kim, Dan Bee [Division of Physical Metrology, Korea Research Institute of Standards and Science, 209 Gajeongno, Yuseong-gu, Daejeon 305-340 (Korea, Republic of); Jung, H.; Gweon, B.; Rhee, J. K.; Choe, W. [Department of Physics, Korea Advanced Institute of Science and Technology, 335 Gwahangno, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Moon, S. Y. [LG Electronics Advanced Research Institute, 16 Woomyeon-Dong, Seocho-Gu, Seoul 137-724 (Korea, Republic of)

2011-04-15T23:59:59.000Z

302

Frequency Regulation Basics and Trends  

SciTech Connect (OSTI)

The electric power system must address two unique requirements: the need to maintain a near real-time balance between generation and load, and the need to adjust generation (or load) to manage power flows through individual transmission facilities. These requirements are not new: vertically integrated utilities have been meeting them for a century as a normal part of conducting business. With restructuring, however, the services needed to meet these requirements, now called ''ancillary services'', are being more clearly defined. Ancillary services are those functions performed by the equipment and people that generate, control, and transmit electricity in support of the basic services of generating capacity, energy supply, and power delivery. The Federal Energy Regulatory Commission (FERC) has defined such services as those ''necessary to support the transmission of electric power from seller to purchaser given the obligations of control areas and transmitting utilities within those control areas to maintain reliable operations of the interconnected transmission system''. This statement recognizes the importance of ancillary services for both bulk-power reliability and support of commercial transactions. Balancing generation and load instantaneously and continuously is difficult because loads and generators are constantly fluctuating. Minute-to-minute load variability results from the random turning on and off of millions of individual loads. Longer-term variability results from predictable factors such as the daily and seasonal load patterns as well as more random events like shifting weather patterns. Generators also introduce unexpected fluctuations because they do not follow their generation schedules exactly and they trip unexpectedly due to a range of equipment failures. The output from wind generators varies with the wind. Storage technologies should be ideal suppliers of several ancillary services, including regulation, contingency reserves (spinning reserve, supplemental reserve, replacement reserve), and voltage support. These services are not free; in regions with energy markets, generators are paid to supply these services. In vertically integrated utilities (without energy markets) the utility incurs significant costs to supply these services. Supplying these services may be a significant business opportunity for emerging storage technologies. This report briefly explores the various ancillary services that may be of interest to storage. It then focuses on regulation, the most expensive ancillary service. It also examines the impact that increasing amounts of wind generation may have on regulation requirements, decreasing conventional regulation supplies, and the implications for energy storage.

Kirby, BJ

2005-05-06T23:59:59.000Z

303

Massive Variability Surveys from Venezuela  

E-Print Network [OSTI]

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.

Cesar Briceno

2003-04-03T23:59:59.000Z

304

Review of Probability Random Variable  

E-Print Network [OSTI]

at close 4) Height of wheel going over a rocky road #12;3 Random Variable Non-examples 1) `Heads' or `Tails' on coin 2) Red or Black ball from urn But we can make these into RV's Basic Idea ­ don't know · Temperature · Wheel height #12;5 Given Continuous RV X... What is the probability that X = x0 ? Oddity : P

Fowler, Mark

305

The ACS LCID project VII: the blue stragglers population in the isolated dSph galaxies Cetus and Tucana  

E-Print Network [OSTI]

We present the first investigation of the Blue Straggler star (BSS) population in two isolated dwarf spheroidal galaxies of the Local Group, Cetus and Tucana. Deep HST/ACS photometry allowed us to identify samples of 940 and 1214 candidates, respectively. The analysis of the star formation histories of the two galaxies suggests that both host a population of BSSs. Specifically, if the BSS candidates are interpreted as young main sequence stars, they do not conform to their galaxy's age-metallicity relationship. The analysis of the luminosity function and the radial distributions support this conclusion, and suggest a non-collisional mechanism for the BSS formation, from the evolution of primordial binaries. This scenario is also supported by the results of new dynamical simulations presented here. Both galaxies coincide with the relationship between the BSS frequency and the absolute visual magnitude Mv found by Momany et al (2007). If this relationship is confirmed by larger sample, then it could be a valuab...

Monelli, M; Mapelli, M; Bernard, E J; Aparicio, A; Skillman, E D; Stetson, P B; Gallart, C; Hidalgo, S L; Mayer, L; Tolstoy, E

2011-01-01T23:59:59.000Z

306

Wide band stepped frequency ground penetrating radar  

DOE Patents [OSTI]

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).

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)

1996-01-01T23:59:59.000Z

307

Frequency Control Performance Measurement and Requirements  

SciTech Connect (OSTI)

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.

Illian, Howard F.

2010-12-20T23:59:59.000Z

308

On frequency dependence of pulsar linear polarization  

E-Print Network [OSTI]

Frequency dependence of pulsar linear polarization is investigated by simulations of emission and propagation processes. Linearly polarized waves are generated through curvature radiation by relativistic particles streaming along curved magnetic field lines, which have ordinary mode (O-mode) and extra-ordinary mode (X-mode) components. As emitted waves propagate outwards, two mode components are separated due to re- fraction of the O mode, and their polarization states are also modified. According to the radius to frequency mapping, low frequency emission is generated from higher magnetosphere, where significant rotation effect leads the X and O modes to be sepa- rated. Hence, the low frequency radiation has a large fraction of linear polarization. As the frequency increases, emission is generated from lower heights, where the rotation effect becomes weaker and the distribution regions of two modes are more overlapped. Hence, more significant depolarization appears for emission at higher frequencies. In addit...

Wang, P F; Han, J L

2015-01-01T23:59:59.000Z

309

Tel: +44 (0) 1603 591574 Email: business@uea.ac.uk Web: www.uea.ac.uk/business Experts model buyer behaviour  

E-Print Network [OSTI]

Tel: +44 (0) 1603 591574 Email: business@uea.ac.uk Web: www.uea.ac.uk/business Experts model buyer their customers to make buying decisions. When you are in the business of printing newspapers, accurate ­ the UK's largest independently-owned regional media business ­ on a project which saw academics from

Everest, Graham R

310

Frequencies Studies Applied to Photovoltaic Modules.  

E-Print Network [OSTI]

?? This master thesis proposes to study applications of frequencies studies to the case of photovoltaic modules and photovoltaic plants. Such studies are little used… (more)

Miquel, Clément

2011-01-01T23:59:59.000Z

311

Low Frequency Noise in Nano-Devices  

E-Print Network [OSTI]

device quality, reliability and the degradation processes. The generation- recombination noise which. His current research interests include low frequency noise, wide-band-gap semiconductors, UV light

312

Multiple frequency printed slot and dipole antennas  

E-Print Network [OSTI]

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....

Kolsrud, Arild

2012-06-07T23:59:59.000Z

313

Variable speed wind turbine generator with zero-sequence filter  

DOE Patents [OSTI]

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.

Muljadi, E.

1998-08-25T23:59:59.000Z

314

Variable speed wind turbine generator with zero-sequence filter  

DOE Patents [OSTI]

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.

Muljadi, Eduard (Golden, CO)

1998-01-01T23:59:59.000Z

315

Variable Speed Wind Turbine Generator with Zero-sequence Filter  

DOE Patents [OSTI]

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.

Muljadi, Eduard (Golden, CO)

1998-08-25T23:59:59.000Z

316

SNL software manual for the ACS Data Analytics Project.  

SciTech Connect (OSTI)

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.

Stearley, Jon R.; McLendon, William Clarence, III; Rodrigues, Arun F.; Williams, Aaron S.; Hooper, Russell Warren; Robinson, David Gerald; Stickland, Michael G.

2011-10-01T23:59:59.000Z

317

Variable flexure-based fluid filter  

DOE Patents [OSTI]

An apparatus and method for filtering particles from a fluid comprises a fluid inlet, a fluid outlet, a variable size passage between the fluid inlet and the fluid outlet, and means for adjusting the size of the variable size passage for filtering the particles from the fluid. An inlet fluid flow stream is introduced to a fixture with a variable size passage. The size of the variable size passage is set so that the fluid passes through the variable size passage but the particles do not pass through the variable size passage.

Brown, Steve B.; Colston Jr., Billy W.; Marshall, Graham; Wolcott, Duane

2007-03-13T23:59:59.000Z

318

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

DOE Patents [OSTI]

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. 6 figs.

Mikesell, H.E.; Lucy, E.

1998-02-03T23:59:59.000Z

319

Analysis and design of a direct AC to AC matrix converter topology  

E-Print Network [OSTI]

functions (a)comparison of three phase inpul, voltages with a sawtooth wave (b)F1 (c)F2 (d)F3 functions obtained from the proposed PVVM. Notice that all triplen harmonics arc eliminated, and the switching frequency and its band components are dominant... + ? AiI, isin((w, + iv, )L + 120] 2 (2. 16) 18 Then, we can see from Eqn. (2. 14), (2. 15) and (2A6), that dominant harmonic components of thc input currents arc ui, and ui, + ui, . These harmonics can be effectively fdtered via L-C network. D...

Choi, Sewan

1992-01-01T23:59:59.000Z

320

Principal Components Instrumental Variable Estimation  

E-Print Network [OSTI]

of the main results are displayed in two appendices. 2 Econometric Framework Consider the simultaneous equations model y = X? + u and X = Z?+ V , (1) 1 An advantage of such general structure is that the ‘large-sample’ condition used in previous studies Kn/ p n... ? 0, where Kn is the number of instruments and n is the sample size, is not required in our asymptotic approximations. 4 where y is the n × 1 vector containing n observations of the dependent variable; X is the n × G matrix with observations...

Winkelried, Diego; Smith, Richard J.

2011-01-31T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Variable Average Absolute Percent Differences  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism inS-4500II FieldVacancy-InducedCloudPoissonVampire Power1 -Variable

322

Variable Mass Theories of Gravity  

E-Print Network [OSTI]

Several attempts to construct theories of gravity with variable mass are considered. The theoretical impacts of allowing the rest mass to vary with respect to time or an appropriate curve parameter are examined in the framework of Newtonian and Einsteinian gravity theories. In further steps, scalar-tensor theories are examined with respect to their relation to the variation of the mass and in an ultimate step, an additional coordinate is introduced and its possible relation to the mass is examined, yielding a five dimensional space-time-matter theory.

M. Leclerc

2002-12-03T23:59:59.000Z

323

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

SciTech Connect (OSTI)

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.

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

2011-05-31T23:59:59.000Z

324

Gravitational Bending of Light with Frequency Shifts  

E-Print Network [OSTI]

Non-static gravitational fields generally introduce frequency shifts when bending light. In this paper, I discuss the frequency shifts induced in the bending of light by moving masses. As examples, I treat the recently discovered high-velocity pulsar PSR 2224+65 and a typical Einstein ring.

P. D. Morley

1993-11-15T23:59:59.000Z

325

Nucleotide Frequency Variation Across Human Genes  

E-Print Network [OSTI]

Nucleotide Frequency Variation Across Human Genes Elizabeth Louie, Jurg Ott, and Jacek Majewski1 The Rockefeller University, New York, New York 10021, USA The frequencies of individual nucleotides exhibit significant fluctuations across eukaryotic genes. In this paper, we investigate nucleotide variation across

Majewski, Jacek

326

Interannual variability in tropospheric nitrous oxide  

E-Print Network [OSTI]

Observations of tropospheric N2O mixing ratio show significant variability on interannual timescales (0.2?ppb, 1 standard deviation). We found that interannual variability in N2O is weakly correlated with that in CFC-12 ...

Thompson, R. L.

327

Utility Variable Generation Integration Group Fall Technical...  

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

Technical Workshop Utility Variable Generation Integration Group Fall Technical Workshop October 15, 2014 9:00AM CDT to October 17, 2014 3:00PM CDT The Utility Variable Generation...

328

Design of dual frequency interferometric SAR  

SciTech Connect (OSTI)

Using a spaceborne interferometric SAR, it is possible to produce a high resolution global topographic map with a height accuracy of several meters. However, frequency selection of the interferometric SAR is rather complicated due to interferometric phenomenology and atmospheric effects. In this paper, we propose a dual frequency interferometric SAR to achieve better understanding of interferometric height (especially for penetrable medium) and corresponding calibration and to remove the atmospheric effects. The selected frequencies are L- and Ku- bands. We also present a radar design and show that a light weight and efficient SAR can be designed using new technologies and dual frequency advantages even with two frequency radars in a single spacecraft. {copyright} {ital 1996 American Institute of Physics.}

Kim, Y.; Edelstein, W.; Caro, E. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

1996-03-01T23:59:59.000Z

329

Contract DE-AC05-76RL01830 Modification M947  

E-Print Network [OSTI]

Contract DE-AC05-76RL01830 Modification M947 J-F-i Part III ­ List of Documents, Exhibits;Contract DE-AC05-76RL01830 Modification M947 J-F-1 OPERATIONAL AGREEMENT BETWEEN THE OFFICE OF SCIENCE;Contract DE-AC05-76RL01830 Modification M947 J-F-2 OPERATIONAL AGREEMENT BETWEEN THE OFFICE OF SCIENCE

330

Contract Number: DE-AC05-76RL01830 Modification M971  

E-Print Network [OSTI]

Contract Number: DE-AC05-76RL01830 Modification M971 PART III ­ List of Documents, Exhibits-Owned Facilities and Real Property J-J-i #12;Contract Number: DE-AC05-76RL01830 Modification M971 ADVANCE AGREEMENT that in consideration of the extension of Contract No. DE- AC05-76RL01830 (hereinafter referred to as "the PNNL Prime

331

Contract No.: DE-AC02-09CH11466 ATTACHMENT J.12  

E-Print Network [OSTI]

Contract No.: DE-AC02-09CH11466 Section J Appendix L J-L-1 ATTACHMENT J.12 APPENDIX L ADMINISTRATIVE SERVICES TO BE PROVIDED TO PPPL BY PRINCETON UNIVERSITY Contract No. DE-AC02-09CH11466 #12;Contract No.: DE-AC02-09CH11466 Section J Appendix L J-L-2 ADMINISTRATIVE SERVICES TO BE PROVIDED TO PPPL

Princeton Plasma Physics Laboratory

332

Programmable AC power supply for simulating power transient expected in fusion reactor  

SciTech Connect (OSTI)

This paper focus on control engineering of the programmable AC power source which has capability to simulate power transient expected in fusion reactor. To generate the programmable power source, AC-AC power electronics converter is adopted to control the power of a set of heaters to represent the transient phenomena of heat exchangers or heat sources of a fusion reactor. The International Thermonuclear Experimental Reactor (ITER) plasma operation scenario is used as the basic reference for producing this transient power source. (authors)

Halimi, B. [Seoul National Univ., Seoul 151-744 (Korea, Republic of); Suh, K. Y. [Seoul National Univ., Seoul 151-744 (Korea, Republic of); PHILOSOPHIA, 1 Gwanak Ro, Gwanak Gu, Seoul 151-744 (Korea, Republic of)

2012-07-01T23:59:59.000Z

333

Nonlinear modal interaction in HVDC/AC power systems with dc power modulation  

SciTech Connect (OSTI)

In this paper investigation of nonlinear modal interaction using the normal form of vector fields technique is extended to HVDC/AC power systems with dc power modulation. The ac-dc interface equations are solved to form a state space model with second order approximation. Using the normal form technique, the system`s nonlinear dynamic characteristics are obtained. The proposed approach is applied to a 4-generator HVDC/AC test power system, and compare with the time domain solution.

Ni, Y.X. [Tsinghua Univ., Beijing (China)] [Tsinghua Univ., Beijing (China); Vittal, V.; Kliemann, W.; Fouad, A.A. [Iowa State Univ., Ames, IA (United States)] [Iowa State Univ., Ames, IA (United States)

1996-11-01T23:59:59.000Z

334

The frequency of planets in multiple systems  

E-Print Network [OSTI]

The frequency of planets in binaries is an important issue in the field of extrasolar planet studies, because of its relevance in estimating of the global planet population of our Galaxy and the clues it can give to our understanding of planet formation and evolution. However, only preliminary estimates are available in the literature. We analyze and compare the frequency of planets in multiple systems to the frequency of planets orbiting single stars. We also try to highlight possible connections between the frequency of planets and the orbital parameters of the binaries (such as the periastron and mass ratio.) A literature search was performed for binaries and multiple systems among the stars of the sample with uniform planet detectability defined by Fischer & Valenti (2005), and 202 of the 850 stars of the sample turned out to be binaries, allowing a statistical comparison of the frequency of planets in binaries and single stars and a study of the run of the planet frequency as a function of the binary separation. We found that the global frequency of planets in the binaries of the sample is not statistically different from that of planets in single stars. Even conservatively taking the probable incompleteness of binary detection in our sample into account, we estimate that the frequency of planets in binaries can be no more than a factor of three lower than that of planets in single stars. There is no significant dependence of planet frequency on the binary separation, except for a lower value of frequency for close binaries. However, this is probably not as low as required to explain the presence of planets in close binaries only as the result of modifications of the binary orbit after the planet formation.

M. Bonavita; S. Desidera

2007-03-29T23:59:59.000Z

335

Phase-stabilized 167 MHz Repetition Frequency Carbon Nanotube Fiber Laser Frequency Comb  

E-Print Network [OSTI]

Phase-stabilized 167 MHz Repetition Frequency Carbon Nanotube Fiber Laser Frequency Comb Jinkang [2, 3]. Mode-locked fiber lasers using single-walled carbon nanotubes as a saturable absorber have-referenced frequency comb from a fiber laser passively modelocked by single walled carbon nanotubes. The carbon

Washburn, Brian

336

E4.18 Radio Frequency Electronics Copyright 2006 Dr Stepan Lucyszyn Frequency Spectrum  

E-Print Network [OSTI]

Applications Phased-array radar Electronic warfare (e.g. Electronic Surveillance Measures, ECM, ECCM, decoysE4.18 Radio Frequency Electronics Copyright © 2006 Dr Stepan Lucyszyn Frequency Spectrum and Applications #12;E4.18 Radio Frequency Electronics Copyright © 2006 Dr Stepan Lucyszyn #12;E4.18 Radio

Papavassiliou, Christos

337

E-Print Network 3.0 - ac power flow Sample Search Results  

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

12;244 MIT... in a periodic fashion is referred to as "ac voltage." ... Source: Massachusetts Institute of Technology (MIT), Computer Science and Artificial Intelligence...

338

E-Print Network 3.0 - ac-dc power transmission Sample Search...  

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

Ris Summary: (AEDVESESY) DFIG control Power control loop Speed control loop Wind turbine control Measurement grid point AC DC... reference DFIG control Power control...

339

E-Print Network 3.0 - ac transit demos Sample Search Results  

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

Streaming Application Summary: , United Kingdom Email: bocek--hecht--hausheer--stiller@ifi.uzh.ch, yehia@comp.lancs.ac.uk Abstract... --This demo shows the CompactPSH...

340

E-Print Network 3.0 - acs residual ischemic Sample Search Results  

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

Search Sample search results for: acs residual ischemic Page: << < 1 2 3 4 5 > >> 1 Brain Research 961 (2003) 2231 www.elsevier.comlocatebrainres Summary: further...

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

E-Print Network 3.0 - ac electrokinetic pump Sample Search Results  

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

Summary: recently been unified with other nonlinear electrokinetic phenomena in microfluidics (2), such as AC... -charge electrokinetic phenomena are finding many new...

342

E-Print Network 3.0 - ac electrokinetic micropumps Sample Search...  

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

research Summary: electrokinetics AC electro-osmosis Induced-charge electrophoresis Microfluidics The field of nonlinear "induced... and others, focused attention on nonlinear...

343

E-Print Network 3.0 - ac joint reconstruction Sample Search Results  

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

reconstructed uniquely and stably from measurement data, ac- quired at all source... TOMOGRAPHY 205 Fig. 5. Reconstructed images corresponding to the noise model in ... Source:...

344

DE-AC05-00OR22725 Modification No. 341  

E-Print Network [OSTI]

Government) to enter into Contract DE-AC05-990R22725 for the Management and Operationofthe OakRidge National

345

DE-AC05-00OR22725 Modification No. 341  

E-Print Network [OSTI]

and the Contractor entered into Agreement No. DE-AC05-000R22725, or a Supplemental Agreement(s) thereto, providing

346

E-Print Network 3.0 - ac railway power-line Sample Search Results  

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

Information Sciences 17 MEASUREMENT AND ANALYSIS OF ELECTROMAGNETIC FIELDS FROM TRAMS, TRAINS AND HYBRID CARS Summary: (AC or DC). Railway safety signalling systems also use...

347

E-Print Network 3.0 - ac-dc parallel tie-lines Sample Search...  

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

of controlling inductions motors driven through ACDC... AC inverter through a transformer and an ACDC rectifier The connection line between the rectifier... range...

348

Calculation of HVDC-converter harmonics in frequency domain with regard to asymmetries and comparison with time domain simulations  

SciTech Connect (OSTI)

In order to study the effects of large HVDC converters to the feeding ac networks, it is of importance to explain and to calculate harmonic phenomena which are a result of converter operation. During commissioning of real HVDC converters it could be seen, that harmonics resulting from unsymmetries in the system voltages or from unsymmetries in converter operation led to significant difficulties concerning the system design. For this reason, not only the effects of characteristic but also the effects of noncharacteristic converter harmonics must be taken into account. The aim is to describe the steady state harmonic behavior of the converter. The harmonic spectra are not determined by time domain analysis but instead the solution is found by frequency domain calculations. This can result in reduced calculation time in comparison to conventional fourier analysis of the time functions. The converter is interpreted as an amplitude modulator with voltage and current converter functions which describe the coupling of the dc circuit and the ac network through the converter. To verify the theory, comparison of frequency domain with time domain calculations were carried out.

Rittiger, J. [Siemens AG, Erlangen (Germany)] [Siemens AG, Erlangen (Germany); Kulicke, B. [Technische Univ. Berlin (Germany)] [Technische Univ. Berlin (Germany)

1995-10-01T23:59:59.000Z

349

Field demonstration of optimized variable speed compressor and condenser fan control for commercial refrigeration systems. Final report  

SciTech Connect (OSTI)

The demonstration project discussed in this report consisted of two separate programs intended to examine methods of implementing variable-frequency drives (VFDs) to increase the efficiency of supermarket refrigeration racks. The first program examined the optimum control strategy for minimizing the power consumption of medium-temperature parallel compressor racks driven by VFDs. The second program, aimed at developing the optimum control strategy for variable-speed control of supermarket condenser fans.

NONE

1997-11-01T23:59:59.000Z

350

Randomness and Earth climate variability  

E-Print Network [OSTI]

Paleo-Sciences including palaeoclimatology and palaeoecology have accumulated numerous records related to climatic changes. The researchers have usually tried to identify periodic and quasi-periodic processes in these paleoscientific records. In this paper, we show that this analysis is incomplete. As follows from our results, random processes, namely processes with a single-time-constant (noise with a Lorentzian noise spectrum), play a very important and, perhaps, a decisive role in numerous natural phenomena. For several of very important natural phenomena the characteristic time constants are very similar and equal to (5-8)x10^3 years. However, this value is not universal. For example, the spectral density fluctuations of the atmospheric radiocarbon 14C are characterized by a Lorentzian with time constant 300 years. The frequency dependence of spectral density fluctuations for benthic 18O records contains two Lorentzians with time constans 8000 years and > 105 years.

Levinshtein, Michael E; Dmitriev, Alexander P; Shmakov, Pavel M

2015-01-01T23:59:59.000Z

351

ac motor control: Topics by E-print Network  

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

Summary: ??Permanent magnet Brushless DC motor drives are being employed in newlinemany variable speed applications due to their high efficiency, silent operation, newlinecompact...

352

ac motor drives: Topics by E-print Network  

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

- TxSpace Summary: and Quantitative Account Gear-Train Servo Error Types. IV. DC VARIABLE SPEED MOTOR DRIVE DESIGN CONSIDERATIONS AND RFALIZATION. Introduction. 27 29 30...

353

ac motor controller: Topics by E-print Network  

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

Summary: ??Permanent magnet Brushless DC motor drives are being employed in newlinemany variable speed applications due to their high efficiency, silent operation, newlinecompact...

354

ac motor drive: Topics by E-print Network  

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

- TxSpace Summary: and Quantitative Account Gear-Train Servo Error Types. IV. DC VARIABLE SPEED MOTOR DRIVE DESIGN CONSIDERATIONS AND RFALIZATION. Introduction. 27 29 30...

355

Creating a fuels baseline and establishing fire frequency relationships to develop a landscape management strategy at the Savannah River Site.  

SciTech Connect (OSTI)

USDA Forest Service Proceedings RMRS-P-41. pp 351-366. Abstract—The Savannah River Site is a Department of Energy Nuclear Defense Facility and a National Environmental Research Park located in the upper coastal plain of South Carolina. Prescribed burning is conducted on 15,000 to 20,000 ac annually. We modifi ed standard forest inventory methods to incorporate a complete assessment of fuel components on 622 plots, assessing coarse woody debris, ladder fuels, and the litter and duff layers. Because of deficiencies in south-wide data on litter-duff bulk densities, which are the fuels most often consumed in prescribed fires, we developed new bulk density relationships. Total surface fuel loading across the landscape ranged from 0.8 to 48.7 tons/ac. The variables basal area, stand age, and site index were important in accounting for variability in ladder fuel, coarse woody debris, and litter-duff for pine types. For a given pine stand condition, litter-duff loading decreased in direct proportion to the number of burns in the preceding thirty years. Ladder fuels for loblolly and longleaf increased in direct proportion to the years since the last prescribed burn. The pattern of fuel loading on the SRS reflects stand dynamics, stand management and fire management. It is suggested that the Forest Inventory and Analysis Program can easily modify sampling protocols to incorporate collection of fuels data.

Parresol, Bernard R.; Shea, Dan; Ottmar, Roger.

2006-10-01T23:59:59.000Z

356

Horizontal coherence of low-frequency fixed-path sound in a continental shelf region with internal-wave activity  

E-Print Network [OSTI]

Horizontal coherence of low-frequency fixed-path sound in a continental shelf region with internal-wave) populated with tidally generated long- and short-wavelength internal waves. Sound paths are 19 km and explain sound field spatial and temporal variability under these conditions. The intermittent internal-wave

357

Variable ratio regenerative braking device  

DOE Patents [OSTI]

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.

Hoppie, Lyle O. (Birmingham, MI)

1981-12-15T23:59:59.000Z

358

Variable delivery, fixed displacement pump  

DOE Patents [OSTI]

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.

Sommars, Mark F. (Sparland, IL)

2001-01-01T23:59:59.000Z

359

Continuously variable focal length lens  

DOE Patents [OSTI]

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.

Adams, Bernhard W; Chollet, Matthieu C

2013-12-17T23:59:59.000Z

360

Variable residence time vortex combustor  

DOE Patents [OSTI]

A variable residence time vortex combustor including a primary combustion chamber for containing a combustion vortex, and a plurality of louvres peripherally disposed about the primary combustion chamber and longitudinally distributed along its primary axis. The louvres are inclined to impel air about the primary combustion chamber to cool its interior surfaces and to impel air inwardly to assist in driving the combustion vortex in a first rotational direction and to feed combustion in the primary combustion chamber. The vortex combustor also includes a second combustion chamber having a secondary zone and a narrowed waist region in the primary combustion chamber interconnecting the output of the primary combustion chamber with the secondary zone for passing only lower density particles and trapping higher density particles in the combustion vortex in the primary combustion chamber for substantial combustion.

Melconian, Jerry O. (76 Beaver Rd., Reading, MA 01867)

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Turbine bucket natural frequency tuning rib  

DOE Patents [OSTI]

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.

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

2002-01-01T23:59:59.000Z

362

High power radio frequency attenuation device  

DOE Patents [OSTI]

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.

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

1984-01-01T23:59:59.000Z

363

Demodulation circuit for AC motor current spectral analysis  

DOE Patents [OSTI]

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

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

1990-12-18T23:59:59.000Z

364

Grassmann Variables and the Jaynes-Cummings Model  

E-Print Network [OSTI]

This paper shows that phase space methods using a positive P type distribution function involving both c-number variables (for the cavity mode) and Grassmann variables (for the two level atom) can be used to treat the Jaynes-Cummings model. Although it is a Grassmann function, the distribution function is equivalent to six c-number functions of the two bosonic variables. Experimental quantities are given as bosonic phase space integrals involving the six functions. A Fokker-Planck equation involving both left and right Grassmann differentiation can be obtained for the distribution function, and is equivalent to six coupled equations for the six c-number functions. The approach used involves choosing the canonical form of the (non-unique) positive P distribution function, where the correspondence rules for bosonic operators are non-standard and hence the Fokker-Planck equation is also unusual. Initial conditions, such as for initially uncorrelated states, are used to determine the initial distribution function. Transformations to new bosonic variables rotating at the cavity frequency enables the six coupled equations for the new c-number functions (also equivalent to the canonical Grassmann distribution function) to be solved analytically, based on an ansatz from a 1980 paper by Stenholm. It is then shown that the distribution function is the same as that determined from the well-known solution based on coupled equations for state vector amplitudes of atomic and n-photon product states. The treatment of the simple two fermion mode Jaynes-Cummings model is a useful test case for the future development of phase space Grassmann distribution functional methods for multi-mode fermionic applications in quantum-atom optics.

Bryan J. Dalton; Barry M. Garraway; John Jeffers; Stephen M. Barnett

2012-03-22T23:59:59.000Z

365

Frequency Instability Problems in North American Interconnections  

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

about such events and be motivated to respond in a more holistic manner. Exhibit 2-7 Combined Cycle Response to Frequency Change Source: NERC 2004 32 Nuclear power plants are...

366

Radio Frequency Identification : regulating information privacy protection  

E-Print Network [OSTI]

As applications of Radio Frequency Identification (RFID) become more profuse, the technology itself is stirring up some controversy. Due to its potential for amassing large amounts of information about both people and ...

Laufer, Deanna (Deanna Raquel)

2007-01-01T23:59:59.000Z

367

Multi-frequency cable vibration experiments  

E-Print Network [OSTI]

A series of Multi-Frequency cable vibration experiments at Reynolds number 7600 were carried out at the MIT Tow Tank using the Virtual Cable Towing Apparatus (VCTA). Motions observed in a Direct Numerical Simulation of a ...

Wiggins, Andrew (Andrew Dale)

2005-01-01T23:59:59.000Z

368

Developing high-frequency equities trading models  

E-Print Network [OSTI]

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 ...

Infantino, Leandro Rafael

2010-01-01T23:59:59.000Z

369

Security approaches for Radio Frequency Identification systems  

E-Print Network [OSTI]

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 ...

Foley, Joseph Timothy, 1976-

2007-01-01T23:59:59.000Z

370

Critical frequency in nuclear chiral rotation  

E-Print Network [OSTI]

Within the cranked Skyrme-Hartree-Fock approach the self-consistent solutions have been obtained for planar and chiral rotational bands in 132La. It turns out that the chiral band cannot exist below some critical rotational frequency which in the present case equals omega=0.6MeV. The appearance of the critical frequency is explained in terms of a simple classical model of two gyroscopes coupled to a triaxial rigid body.

P. Olbratowski; J. Dobaczewski; J. Dudek

2002-11-25T23:59:59.000Z

371

LinShim6 -Implementation of the Shim6 protocol http://inl.info.ucl.ac.be/LinShim6  

E-Print Network [OSTI]

LinShim6 - Implementation of the Shim6 protocol http://inl.info.ucl.ac.be/LinShim6 Documentation at http://inl.info.ucl. ac.be/publications/shim6-masterthesis. Like the whole project, this documentation

Bonaventure, Olivier

372

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

E-Print Network [OSTI]

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 ...

Hwang, J. George

373

Probing Mott lobes via the AC Josephson effect  

E-Print Network [OSTI]

The alternating-current (AC) Josephson effect is studied in a system consisting of two weakly coupled Bose Hubbard models. In the framework of the mean field theory, Gross-Pitaevskii equations show that the amplitude of the Josephson current is proportional to the product of superfluid order parameters. In addition, the chemical potential--current relation for a small size system is obtained via the exact numerical computation. This allows us to propose a feasible experimental scheme to measure the Mott lobes of the quantum phase transition.

M. X. Huo; Ying Li; Z. Song; C. P. Sun

2008-03-04T23:59:59.000Z

374

Contract DE-AC06-08RL14788  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New SubstationCleanCommunity2Workshops 2008O"Program andAC02-07CH11358December

375

Analysis of the Irregular Pulsations of AC Her  

E-Print Network [OSTI]

The AAVSO lightcurve data of the irregularly pulsating star AC Herculis of the RV Tau class are analysed. The lightcurve is shown to be incompatible with a periodic, or even multiperiodic pulsation, even if allowance is made for evolution. Instead the best explanation is that the irregularly alternating cycles are a manifestation of low dimensional chaos. The lightcurve is found to be generated by a 3 or 4 dimensional dynamics -- 3 or 4 first order ODEs. The (Lyapunov) fractal dimension of the underlying dynamic attractor is computed to be d_L ~ 2.2, smaller than the value of d_L ~ 3.1 found for R Sct.

Z. Kollath; J. R. Buchler; T. Serre; J. Mattei

1997-07-08T23:59:59.000Z

376

Extremely high frequency RF effects on electronics.  

SciTech Connect (OSTI)

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.

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

2012-01-01T23:59:59.000Z

377

Investigation of Multi-Frequency Power Transmission and System  

E-Print Network [OSTI]

BACKGROUND .................................................................................. 6 A. High Voltage Direct Current Transmission (HVDC) ................ 6 B. Flexible AC Transmission System (FACTS) ............................ 12... ......................................................................................................................... 80 viii LIST OF FIGURES FIGURE Page 1 Schematic of a HVDC Transmission Line...

Barazarte Conte, Ronald

2012-10-19T23:59:59.000Z

378

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

E-Print Network [OSTI]

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

Sarawagi, Sunita

379

Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid  

E-Print Network [OSTI]

Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid-- With the penetration of renewable energy in modern power system, microgrid has become a popular application worldwide. In this paper, parallel-connected bidirectional converters for AC and DC hybrid microgrid application

Teodorescu, Remus

380

Synthesis Gas Production from Partial Oxidation of Methane with Air in AC Electric Gas Discharge  

E-Print Network [OSTI]

Synthesis Gas Production from Partial Oxidation of Methane with Air in AC Electric Gas Discharge K 73019 Received October 11, 2002 In this study, synthesis gas production in an AC electric gas discharge of methane and air mixtures at room temperature and ambient pressure was investigated. The objective

Mallinson, Richard

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

The Hybrid Power Flow Controller A New Concept for Flexible AC Transmission  

E-Print Network [OSTI]

The Hybrid Power Flow Controller A New Concept for Flexible AC Transmission Jovan Z. Bebic Electric flow controller topologies are proposed for flexible AC transmission systems (FACTS). The first one or series capacitors can be enhanced to generalized power flow control ­ a functionality commonly associated

Lehn, Peter W.

382

For information on current fee levels, see: www.strath.ac.uk/registry/students/finance  

E-Print Network [OSTI]

Fees For information on current fee levels, see: www.strath.ac.uk/registry/students/finance How Enquiries can be made to either of the following in the Department of Accounting & Finance: Professor Dick Davies Course Director, Investment & Finance t: +44 (0)141 548 3710 e: jr.davies@strath.ac.uk Barbara

Mottram, Nigel

383

Contract Number: DE-AC05-76RL01830 Modification M920  

E-Print Network [OSTI]

Contract Number: DE-AC05-76RL01830 Modification M920 Part III ­ List of Documents, Exhibits, And Other Attachments Section J List of Attachments J ­ i #12;Contract Number: DE-AC05-76RL01830

384

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 controller for a wind farm made-up exclusively of active stall wind turbines with AC grid connection wind farm control involves both the control on wind turbine level as well as the central control

385

ForReview.Confidential-ACS Plantwide Control to Economic Optimum of a Recycle  

E-Print Network [OSTI]

ForReview.Confidential-ACS Plantwide Control to Economic Optimum of a Recycle Process with Side #12;ForReview.Confidential-ACS Plantwide Control to Economic Optimum of a Recycle Process with Side, Trondheim N7491, Norway Abstract Plantwide control system design for economically optimum operation

Skogestad, Sigurd

386

Ultrafast high-pressure AC electro-osmotic pumps for portable biomedical microfluidics  

E-Print Network [OSTI]

Ultrafast high-pressure AC electro-osmotic pumps for portable biomedical microfluidics Chien details the development of an integrated AC electro-osmotic (ACEO) microfluidic pump for dilute (100 mM) biological solutions in separate microfluidic devices, with potential applications in portable

Bazant, Martin Z.

387

* jafleeman@aep.com EHV AC and HVDC Transmission Working Together to Integrate Renewable Power  

E-Print Network [OSTI]

* jafleeman@aep.com EHV AC and HVDC Transmission Working Together to Integrate Renewable Power J. A current (EHV AC) and high voltage direct current (HVDC) transmission systems and advocates a hybrid as a high capacity platform for system integration. HVDC transmission offers express, efficient delivery

McCalley, James D.

388

AC PV Modules Take a standard DC PV module and connect a microinverter  

E-Print Network [OSTI]

modules. These inverters range in power from 700 watts up to 1 megawatt. DC maximum system voltages can and up to 13 inverters for the 210 W version to be installed on the same AC output cable. home power 136, and secure a listing to UL1741 for a pre-assembled module/inverter device, and you have an AC PV module

Johnson, Eric E.

389

ePOWER Seminar AC solar cells: A new breed of PV power generation  

E-Print Network [OSTI]

ePOWER Seminar AC solar cells: A new breed of PV power generation Professor Faisal Khan Assistant dc output which needs to be processed and inverted for ac applications. Using a modern manufacturing facility, PV panels could be mass produced without any apparent issues. Unfortunately, power converters

Abolmaesumi, Purang

390

HCCI in a Variable Compression Ratio Engine: Effects of Engine...  

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

Fuels Practical Full Time HCCI Operation Will Require Specific HCCI Fuel Low Octane gasoline Experimental Variables Experimental Variables Engine Variables Intake Manifold...

391

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

E-Print Network [OSTI]

.haszeldine@ed.ac.uk Scottish Centre for Carbon Storage, Petrobras 2008 5 Connecting CCS companies 2007: Largest CO2 Storage in India Predicting seal in overburden Natural CO2 sites #12;s.haszeldine@ed.ac.uk Scottish Centre://www.geos.ed.ac.uk/sccs/ s.haszeldine@ed.ac.uk Scottish Centre for Carbon Storage, Petrobras 2008 12 7: CO2 Capture from

Haszeldine, Stuart

392

RELATIONSHIP BETWEEN LOW AND HIGH FREQUENCIES IN {delta} SCUTI STARS: PHOTOMETRIC KEPLER AND SPECTROSCOPIC ANALYSES OF THE RAPID ROTATOR KIC 8054146  

SciTech Connect (OSTI)

Two years of Kepler data of KIC 8054146 ({delta} Sct/{gamma} Dor hybrid) revealed 349 statistically significant frequencies between 0.54 and 191.36 cycles day{sup -1} (6.3 {mu}Hz to 2.21 mHz). The 117 low frequencies cluster in specific frequency bands, but do not show the equidistant period spacings predicted for gravity modes of successive radial order, n, and reported for at least one other hybrid pulsator. The four dominant low frequencies in the 2.8-3.0 cycles day{sup -1} (32-35 {mu}Hz) range show strong amplitude variability with timescales of months and years. These four low frequencies also determine the spacing of the higher frequencies in and beyond the {delta} Sct pressure-mode frequency domain. In fact, most of the higher frequencies belong to one of three families with spacings linked to a specific dominant low frequency. In the Fourier spectrum, these family regularities show up as triplets, high-frequency sequences with absolutely equidistant frequency spacings, side lobes (amplitude modulations), and other regularities in frequency spacings. Furthermore, within two families the amplitude variations between the low and high frequencies are related. We conclude that the low frequencies (gravity modes, rotation) and observed high frequencies (mostly pressure modes) are physically connected. This unusual behavior may be related to the very rapid rotation of the star: from a combination of high- and low-resolution spectroscopy we determined that KIC 8054146 is a very fast rotator ({upsilon} sin i = 300 {+-} 20 km s{sup -1}) with an effective temperature of 7600 {+-} 200 K and a surface gravity log g of 3.9 {+-} 0.3. Several astrophysical ideas explaining the origin of the relationship between the low and high frequencies are explored.

Breger, M.; Robertson, P. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Fossati, L. [Department of Physical Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Balona, L. [South African Astronomical Observatory, P.O. Box 9, Observatory 7935 (South Africa); Kurtz, D. W. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Bohlender, D. [Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Lenz, P. [N. Copernicus Astronomical Center, Polish Academy of Sciences, ul. Bartycka 18, 00-716 Warszawa (Poland); Mueller, I.; Lueftinger, Th. [Institut fuer Astronphysik der Universitaet Wien, Tuerkenschanzstr. 17, A-1180 Wien (Austria); Clarke, Bruce D. [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Hall, Jennifer R.; Ibrahim, Khadeejah A. [Orbital Sciences Corporation/NASA Ames Research Center, Moffett Field, CA 94035 (United States)

2012-11-01T23:59:59.000Z

393

Development of a 10 kW High Temperature High Power Density Three-Phase AC-DC-AC SiC Converter  

SciTech Connect (OSTI)

This paper presents the development and experimental performance of a 10 kW, all SiC, 250 C junction temperature high-power-density three-phase ac-dc-ac converter. The electromagnetic interference filter, thermal system, high temperature package, and gate drive design are discussed in detail. Finally, tests confirming the feasibility and validating the theoretical basis of the prototype converter system are described.

Ning, Puqi [ORNL

2012-01-01T23:59:59.000Z

394

HERSCHEL OBSERVATIONS OF CATACLYSMIC VARIABLES  

SciTech Connect (OSTI)

We have used the PACS instrument on the Herschel Space Observatory to observe eight cataclysmic variables at 70 and 160 {mu}m. Of these eight objects, only AM Her was detected. We have combined the Herschel results with ground-based, Spitzer, and WISE observations to construct spectral energy distributions for all of the targets. For the two dwarf novae in the sample, SS Cyg and U Gem, we find that their infrared luminosities are completely dominated by their secondary stars. For the two highly magnetic 'polars' in our survey, AM Her and EF Eri, we find that their mid-infrared excesses, previously attributed to circumbinary dust emission, can be fully explained by cyclotron emission. The WISE light curves for both sources show large, orbitally modulated variations that are identically phased to their near-IR light curves. We propose that significant emission from the lowest cyclotron harmonics (n {<=} 3) is present in EF Eri and AM Her. Previously, such emission would have been presumed to be optically thick, and not provide significant orbitally modulated flux. This suggests that the accretion onto polars is more complicated than assumed in the simple models developed for these two sources. We develop a model for the near-/mid-IR light curves for WZ Sge with an L2 donor star that shows that the ellipsoidal variations from its secondary star are detected. We conclude that none of the targets surveyed have dusty circumbinary disks.

Harrison, Thomas E.; Hamilton, Ryan T. [Department of Astronomy, New Mexico State University, Box 30001, MSC 4500, Las Cruces, NM 88003-8001 (United States); Tappert, Claus [Departamento de Fisica y Astronomia, Universidad de Valparaiso, Avda. Gran Bretana 1111, Valparaiso (Chile); Hoffman, Douglas I. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Campbell, Ryan K., E-mail: tharriso@nmsu.edu, E-mail: rthamilt@nmsu.edu, E-mail: claus.tappert@uv.cl, E-mail: dhoffman@ipac.caltech.edu, E-mail: Ryan.Campbell@humobldt.edu [Department of Physics and Astronomy, Humboldt State University, 1 Harpst St., Arcata, CA 95521 (United States)

2013-01-01T23:59:59.000Z

395

ISM band to U-NII band frequency transverter and method of frequency transversion  

DOE Patents [OSTI]

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.

Stepp, Jeffrey David (Grandview, MO); Hensley, Dale (Grandview, MO)

2006-04-04T23:59:59.000Z

396

Data:8364dcbb-76ca-48ac-929d-9738a1432ac7 | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office695810186 No revisione0a2d50bdf No revision has9-c45258b300ac Noc1e69d7992f-3f3dd886bf1c1dc0188f0 No revision

397

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

E-Print Network [OSTI]

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

Qiu, Li

398

COUNTRY INSTITUTION DATE WEB ADDRESS IRAN University of Art Isfahn 08.03.2007 http://www.aui.ac.ir  

E-Print Network [OSTI]

COUNTRY INSTITUTION DATE WEB ADDRESS IRAN University of Art Isfahn 08.03.2007 http://www.aui.ac.ir IRAN Isfahn University of Technology 08.03.2007 http://www.iut.ac.ir IRAN The University of Isfahn 15/03/2011 http://www.ui.ac.ir IRAN Shahid Bahonar University of Kermn 06.06.2005 http

Di Pillo, Gianni

399

Eccentric crank variable compression ratio mechanism  

DOE Patents [OSTI]

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.

Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)

2008-05-13T23:59:59.000Z

400

Variable-Period Undulators For Synchrotron Radiation  

DOE Patents [OSTI]

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.

Shenoy, Gopal (Naperville, IL); Lewellen, John (Plainfield, IL); Shu, Deming (Darien, IL); Vinokurov, Nikolai (Novosibirsk, RU)

2005-02-22T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Variable-Period Undulators for Synchrotron Radiation  

SciTech Connect (OSTI)

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.

Shenoy, Gopal; Lewellen, John; Shu, Deming; Vinokurov, Nikolai

2005-02-22T23:59:59.000Z

402

Multivector Functions of a Real Variable  

E-Print Network [OSTI]

This paper is an introduction to the theory of multivector functions of a real variable. The notions of limit, continuity and derivative for these objects are given. The theory of multivector functions of a real variable, even being similar to the usual theory of vector functions of a real variable, has some subtle issues which make its presentation worhtwhile.We refer in particular to the derivative rules involving exterior and Clifford products, and also to the rule for derivation of a composition of an ordinary scalar function with a multivector function of a real variable.

A. M. Moya; V. V. Fernández; W. A. Rodrigues Jr

2002-12-17T23:59:59.000Z

403

Hybrid Bayesian Networks with Linear Deterministic Variables  

E-Print Network [OSTI]

Conference (UAI-05), 2005, AUAI Press, Arlington, VA. 136 Y X Z Figure 2: A Bayesian Network Representation of the Mixed Distribution for X. this example, Y is a discrete variable with state space ? Y = {1,2,3}, Z is a real-valued variable, and X is a... conditionally deterministic variable whose condi- tional distribution is described as follows: X |{y,z} = y if y =1,2 and X |{y,z} = z if y =3. Potentials of the type described above are used in this paper to represent distributions of variables in hy- brid...

Cobb, Barry R.; Shenoy, Prakash P.

2005-07-01T23:59:59.000Z

404

Variable-speed wind power system with improved energy capture via multilevel conversion  

DOE Patents [OSTI]

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.

Erickson, Robert W.; Al-Naseem, Osama A.; Fingersh, Lee Jay

2005-05-31T23:59:59.000Z

405

Climate dynamics and fluid mechanics: Natural variability and related uncertainties  

E-Print Network [OSTI]

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.

Michael Ghil; Mickaël D. Chekroun; Eric Simonnet

2010-06-15T23:59:59.000Z

406

High frequency inductive lamp and power oscillator  

DOE Patents [OSTI]

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.

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)

2001-01-01T23:59:59.000Z

407

High frequency inductive lamp and power oscillator  

DOE Patents [OSTI]

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.

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)

2000-01-01T23:59:59.000Z

408

Radar network communication through sensing of frequency hopping  

DOE Patents [OSTI]

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.

Dowla, Farid; Nekoogar, Faranak

2013-05-28T23:59:59.000Z

409

Volume-Duration-Frequencies for Ungaged Catchments in Texas  

E-Print Network [OSTI]

-Duration-Frequencies Ungaged Catchments in Texas: Computations of Flood Volumes of Varying Durations and Frequencies for Catchments with Areas Greater than 300 Square Miles) lists the actual flood volumes computed for different duration- frequencies at all rural, unregulated...

Devulapalli, Ravi S.; Valdes, Juan B.

410

Study of the OCS6 Lattice Using Frequency Maps  

E-Print Network [OSTI]

Frequency maps for the OCS5 and OCS6Frequency maps for the OCS6 lattice for a tune of Q x =tunes. . . . . . . . . Frequency maps for the OCS6 lattice

Reichel, Ina

2007-01-01T23:59:59.000Z

411

The Matrix Converter Drive Performance Under Abnormal Input Voltage Conditions  

E-Print Network [OSTI]

that generates variable magnitude variable frequency output voltage from the ac utility line. It has high power conversion device, the disturbances at the ac utility grid (line) side are immediately reflected to the load and large capacitor associated with it, there is no stored energy in the MC. As a result, the utility line

Hava, Ahmet

412

TIME-FREQUENCY-PHASE TRACKING APPROACH : APPLICATION TO UNDERWATER SIGNALS IN A PASSIVE CONTEXT  

E-Print Network [OSTI]

of Montenegro, Podgorica ­ MONTENEGRO E-mail : srdjan@cg.ac.yu ABSTRACT One of the most challenging applications

Paris-Sud XI, Université de

413

Frequency dependence of the Chiral Vortical Effect  

E-Print Network [OSTI]

We study the frequency dependence of all the chiral vortical and magnetic conductivities for a relativistic gas of free chiral fermions and for a strongly coupled conformal field theory with holographic dual in four dimensions. Both systems have gauge and gravitational anomalies, and we compute their contribution to the conductivities. The chiral vortical conductivities and the chiral magnetic conductivity in the energy current show a frequency dependence in the form of a delta centered at zero frequency. This highly discontinuous behavior is a natural consequence of the Ward identities that include the energy momentum tensor. We discuss the physical interpretation of this result and its possible implications for the quark gluon plasma as created in heavy ion collisions. In the Appendix we discuss why the chiral magnetic effect seems to vanish in the consistent current for a particular implementation of the axial chemical potential.

Karl Landsteiner; Eugenio Megias; Francisco Peña Benítez

2014-09-18T23:59:59.000Z

414

Integration of Full Tensor Gravity and ZTEM Passive Low Frequency...  

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

Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition Integration of Full Tensor Gravity and ZTEM Passive Low Frequency...

415

Solar Dynamics Observatory/ Extreme Ultraviolet Variability Experiment  

E-Print Network [OSTI]

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

Mojzsis, Stephen J.

416

Variable Speed Pumping for Level Control  

E-Print Network [OSTI]

The purpose of this paper is to describe an application of variable speed pumping to level control of an industrial process. Topics include a comparison of the process using control valves with a variable speed system, an energy savings and cost...

Vasel, M.

1982-01-01T23:59:59.000Z

417

Practical evaluation of action-angle variables  

SciTech Connect (OSTI)

A practical method is described for establishing action-angle variables for a Hamiltonian system. That is, a given nearly integrable Hamiltonian is divided into an exactly integrable system plus a perturbation in action-angle form. The transformation of variables, which is carried out using a few short trajectory integrations, permits a rapid determination of trajectory properties throughout a phase space volume.

Boozer, A.H.

1984-02-01T23:59:59.000Z

418

Quantum Computing and Hidden Variables Scott Aaronson #  

E-Print Network [OSTI]

Quantum Computing and Hidden Variables Scott Aaronson # Institute for Advanced Study, Princeton of a hidden variable, then we could e#ciently solve problems that are believed to be intractable even powerful than the quantum computing model. PACS numbers: 03.65.Ta, 03.65.Ud, 03.67.Lx, 02.70.­c I

Aaronson, Scott

419

Deutsch-Jozsa algorithm for continuous variables  

E-Print Network [OSTI]

We present an idealized quantum continuous variable analog of the Deutsch-Jozsa algorithm which can be implemented on a perfect continuous variable quantum computer. Using the Fourier transformation and XOR gate appropriate for continuous spectra we show that under ideal operation to infinite precision that there is an infinite reduction in number of query calls in this scheme.

Arun K. Pati; Samuel L. Braunstein

2002-07-18T23:59:59.000Z

420

The Galex Ultraviolet Variability (GUVV) Catalog  

E-Print Network [OSTI]

We present Version 1.0 of the NASA Galaxy Evolution Explorer (GALEX) ultraviolet variability catalog (GUVV) that contains information on 84 time-variable and transient sources gained with simultaneous near and far ultraviolet photometric observations. These time-variable sources were serendipitously revealed in the various 1.2 degree star fields currently being surveyed by the GALEX satellite in two ultraviolet bands (NUV 1750-2750A, FUV 1350-1750A) with limiting AB magnitudes of 23-25. The largest-amplitude variable objects presently detected by GALEX are M-dwarf flare stars, which can brighten by 5-10 mag in both the NUV and FUV bands during short duration (< 500s) outbursts. Other types of large-amplitude ultraviolet variable objects include ab-type RR Lyrae stars, which can vary periodically by 2-5mag in the GALEX FUV band. This first GUVV catalog lists galactic positions and possible source identifications in order to provide the astronomical community with a list of time-variable objects that can now be repeatedly observed at other wavelengths. We expect the total number of time-variable source detections to increase as the GALEX mission progresses, such that later version numbers of the GUVV catalog will contain substantially more variable sources.

Barry Y. Welsh; Jonathan M. Wheatley; Kenneth Heafield; Mark Seibert; Stanley E. Browne; Samir Salim; R. Michael Rich; Tom A. Barlow; Luciana Bianchi; Yong-Ik Byun; Jose Donas; Karl Forster; Peter G. Friedman; Timothy M. Heckman; Patrick N. Jelinsky; Young-Wook Lee; Barry F. Madore; Roger F. Malina; D. Christopher Martin; Bruno Milliard; Patrick Morrissey; Susan G. Neff; David Schiminovich; Oswald H. W. Siegmund; Todd Small; Alex S. Szalay; Ted K. Wyder

2005-04-21T23:59:59.000Z

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network [OSTI]

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 at the outlet nozzle will bum flesh. Do not tum on Heat Gun with hand in front of nozzle. DO NOT USE NEAR equipment Specifications Temperature Variable from 212" F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

422

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network [OSTI]

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 at the outlet nozzle will bum flesh. Do not tum on Heat Gun with hand in front of nozzle. DO NOT USE NEAR equipment Specifications Temperature Variable from 212° F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

423

Computing Instantaneous Frequency by normalizing Hilbert Transform  

DOE Patents [OSTI]

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.

Huang, Norden E.

2005-05-31T23:59:59.000Z

424

Undulations from amplified low frequency surface waves  

SciTech Connect (OSTI)

We study the linear scattering of gravity waves in longitudinal inhomogeneous stationary flows. When the flow becomes supercritical, it is known that counterflow propagating shallow waves are blocked and converted into deep waves. Here we show that in the zero-frequency limit, the reflected waves are amplified in such a way that the free surface develops an undulation, i.e., a zero-frequency wave of large amplitude with nodes located at specific places. This amplification involves negative energy waves and implies that flat surfaces are unstable against incoming perturbations of arbitrary small amplitude. The relation between this instability and black hole radiation (the Hawking effect) is established.

Coutant, Antonin, E-mail: antonin.coutant@aei.mpg.de [Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Am Muhlenberg 1, 14476 Golm (Germany)] [Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Am Muhlenberg 1, 14476 Golm (Germany); Parentani, Renaud, E-mail: renaud.parentani@th.u-psud.fr [Laboratoire de Physique Théorique, CNRS UMR 8627, Bâtiment 210, Université Paris-Sud 11, 91405 Orsay Cedex (France)] [Laboratoire de Physique Théorique, CNRS UMR 8627, Bâtiment 210, Université Paris-Sud 11, 91405 Orsay Cedex (France)

2014-04-15T23:59:59.000Z

425

Seismic isolation systems with distinct multiple frequencies  

DOE Patents [OSTI]

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.

Wu, Ting-shu (Downers Grove, IL); Seidensticker, Ralph W. (Wheaton, IL)

1990-01-01T23:59:59.000Z

426

Frequency locking in an injection-locked frequency divider Michele V. Bartuccelli  

E-Print Network [OSTI]

experimentally, and the devil's staircase structure of the lockings is measured: when the ratio of the frequency of the driving frequency. We provide explicit formulae for the width of the plateaux appearing in the devil's staircase structure of the lockings, and in particular show that the largest plateaux correspond to even

Gentile, Guido

427

Frequency locking in the injection-locked frequency divider Michele V. Bartuccelli  

E-Print Network [OSTI]

- tally, and the devil's staircase structure of the lockings is measured: when the ratio of the frequency of the driving frequency. We provide explicit formulae for the width of the plateaux appearing in the devil's staircase structure of the lockings, and in particular show that the largest plateaux correspond to even

Roma "La Sapienza", Università di

428

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)

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.

Lebedeva, A. I.; Zorchenko, N. V.; Prudnikov, A. A.

2011-09-15T23:59:59.000Z

429

FLUXCAP: A flux-coupled ac/dc magnetizing device  

E-Print Network [OSTI]

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.

Gopman, Daniel B; Kent, Andrew D

2012-01-01T23:59:59.000Z

430

Oscillator Architectures and Enhanced Frequency Synthesizer  

E-Print Network [OSTI]

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...

Park, Sang Wook

2009-11-16T23:59:59.000Z

431

Broadband frequency mode entanglement in waveguided PDC  

E-Print Network [OSTI]

We report the observation of beatings of the coincidence event rate in a Hong-Ou-Mandel interference (HOMI) between signal and idler photons from a parametric downconversion process inside a multi-mode KTP waveguide. As explanation we introduce bi-photonic states entangled in their broadband frequency modes and propose a suitable entanglement witness.

Eckstein, Andreas

2008-01-01T23:59:59.000Z

432

Broadband frequency mode entanglement in waveguided PDC  

E-Print Network [OSTI]

We report the observation of beatings of the coincidence event rate in a Hong-Ou-Mandel interference (HOMI) between signal and idler photons from a parametric downconversion (PDC) process inside a multi-mode KTP waveguide. As explanation we introduce bi-photonic states entangled in their broadband frequency modes generated by waveguide mode triples and propose a suitable entanglement detection scheme.

Andreas Eckstein; Christine Silberhorn

2008-07-04T23:59:59.000Z

433

Fiber type, meal frequency and colonic cytokinetics  

E-Print Network [OSTI]

The effects of dietary fiber type (cellulose, pectin or oat bran) and meal frequency (gorge or nibble) on colonic short chain fatty acids (SCFAs), in vivo colonic pH and epithelial cell proliferation were examined in male Sprague-Dawley rats...

Zhang, Jianhu

1993-01-01T23:59:59.000Z

434

Phase-locking of driven vortex lattices with transverse ac force and periodic pinning  

SciTech Connect (OSTI)

For a vortex lattice moving in a periodic array we show analytically and numerically that a new type of phase locking occurs in the presence of a longitudinal dc driving force and a transverse ac driving force. This phase locking is distinct from the Shapiro step phase locking found with longitudinal ac drives. We show that an increase in critical current and a fundamental phase-locked step width scale with the square of the driving ac amplitude. Our results should carry over to other systems such as vortex motion in Josephson-junction arrays.

Reichhardt, Charles; Kolton, Alejandro B.; Dominguez, Daniel; Gronbech-Jensen, Niels

2001-10-01T23:59:59.000Z

435

Test plan for performance testing of the Eaton AC-3 electric vehicle  

SciTech Connect (OSTI)

An alternating current (ac) propulsion system for an electric vehicle has been developed and tested by the Eaton Corporation. The test bed vehicle is a modified 1981 Mercury Lynx. The test plan has been prepared specifically for the third modification to this test bed and identified as the Eaton AC-3. The scope of the EG and G testing at INEL to be done on the Eaton AC-3 will include coastdown and dynamometer tests but will not include environmental, on-road, or track testing. Coastdown testing will be performed in accordance with SAE J-1263 (SAE Recommended Practice for Road Load Measurement and Dynamometer Simulation Using Coastdown Techniques).

Crumley, R.L.; Heiselmann, H.W.

1985-04-01T23:59:59.000Z

436

Segmented superconducting tape having reduced AC losses and method of making  

DOE Patents [OSTI]

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.

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)

2009-09-22T23:59:59.000Z

437

EMTP modeling of CIGRE benchmark based HVDC transmission system operating with weak AC systems  

SciTech Connect (OSTI)

An EMTP based study of a CIGRE benchmark based HVDC system operating with weak ac systems is carried out. The modeled system provides a starting point for (a) educators teaching HVDC transmission courses and (b) for utility planners to develop their own low-cost dedicated digital simulators for training purposes. In this paper, modeling details of the ac-dc system, dc converters and control are presented. To validate the control schemes presented, the HVDC system is tested under ac-dc fault conditions. Results obtained from an EMTP-based study under these fault conditions are also presented in this paper.

Sood, V.K. [Hydro-Quebec, Varennes, Quebec (Canada); Khatri, V.; Jin, H. [Concordia Univ., Montreal, Quebec (Canada). Dept. of Electrical and Computer Engineering

1995-12-31T23:59:59.000Z

438

Dynamic performance of a STATCON at an HVDC inverter feeding a very weak AC system  

SciTech Connect (OSTI)

This paper investigates the dynamic performance of the advanced static var compensator or STATCON at a high voltage direct current (HVDC) converter terminal where the ac system has a very low short circuit ratio (SCR). The STATCON is based on a nine-level GTO thyristor inverter. The studies include operating characteristics of the STATCON under various ac and dc disturbances. The simulation results are compared with other types of reactive power compensation options available for such applications. It is shown that the STATCON has clear advantages over the other compensators, in areas such as; fault response time, voltage support ability, and dc recovery, while operating with very weak ac systems.

Zhuang, Y.; Menzies, R.W. [Univ. of Manitoba, Winnipeg, Manitoba (Canada)] [Univ. of Manitoba, Winnipeg, Manitoba (Canada); Nayak, O.B. [HVDC Research Centre, Winnipeg, Manitoba (Canada)] [HVDC Research Centre, Winnipeg, Manitoba (Canada); Turanli, H.M. [Manitoba Hydro, Winnipeg, Manitoba (Canada)] [Manitoba Hydro, Winnipeg, Manitoba (Canada)

1996-04-01T23:59:59.000Z

439

A comparison of two variables in relaxation  

E-Print Network [OSTI]

A COMPARISON OF TWO VARIABLES IN RELAXATION A Thesis by PAUL EDWIN TURNER Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1974 Major Subject...: Psychology A COMPARiSON OF TWO VARIABLES IN RELAXATION A Thesis by PAUL EDWIN TURNER Approved as to style and content by: (Chairman of Committ Head of Dep tment Member ?2 J L, ~Xi~ Member M-. ~~2 y May 1974 ABSTRACT A Comparison of Two Variable...

Turner, Paul Edwin

1974-01-01T23:59:59.000Z

440

Heterogeneity of Nucleotide Frequencies Among Evolutionary Lineages and Phylogenetic Inference  

E-Print Network [OSTI]

Heterogeneity of Nucleotide Frequencies Among Evolutionary Lineages and Phylogenetic Inference is the homogeneity of nucleotide frequencies among taxa, which refers to the equality of the nucleotide frequency bias among species. Changes in nucleotide frequency among different lineages in a data set are thought

Rosenberg, Michael S.

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Laser Frequency Stabilization with Optical Cavities Anya M. Davis  

E-Print Network [OSTI]

Laser Frequency Stabilization with Optical Cavities Anya M. Davis Walla Walla University University Effective laser cooling requires the laser's frequency to be precise, with a frequency drift of no more than lasers for correcting frequency drift. In the University of Washington Quantum Computing with Trapped

Blinov, Boris

442

Suppression of chaos at slow variables by rapidly mixing fast dynamics through linear energy-preserving coupling  

E-Print Network [OSTI]

Chaotic multiscale dynamical systems are common in many areas of science, one of the examples being the interaction of the low-frequency dynamics in the atmosphere with the fast turbulent weather dynamics. One of the key questions about chaotic multiscale systems is how the fast dynamics affects chaos at the slow variables, and, therefore, impacts uncertainty and predictability of the slow dynamics. Here we demonstrate that the linear slow-fast coupling with the total energy conservation property promotes the suppression of chaos at the slow variables through the rapid mixing at the fast variables, both theoretically and through numerical simulations. A suitable mathematical framework is developed, connecting the slow dynamics on the tangent subspaces to the infinite-time linear response of the mean state to a constant external forcing at the fast variables. Additionally, it is shown that the uncoupled dynamics for the slow variables may remain chaotic while the complete multiscale system loses chaos and becomes completely predictable at the slow variables through increasing chaos and turbulence at the fast variables. This result contradicts the common sense intuition, where, naturally, one would think that coupling a slow weakly chaotic system with another much faster and much stronger mixing system would result in general increase of chaos at the slow variables.

Rafail V. Abramov

2011-08-14T23:59:59.000Z

443

Graphene-coated coupling coil for AC resistance reduction  

DOE Patents [OSTI]

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.

Miller, John M

2014-03-04T23:59:59.000Z

444

Lift-and-Project Relaxations of AC Microgrid Distribution System Planning  

E-Print Network [OSTI]

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 ...

Taylor, Joshua A.

2011-01-01T23:59:59.000Z

445

Rotating electrical machines - Part 22: AC generators for reciprocating internal combustion (RIC) engine driven generating sets  

E-Print Network [OSTI]

Establishes the principal characteristics of a.c. generators under the control of their voltage regulators when used for reciprocating internal combustion engine driven generating sets. Supplements the requirements given in IEC 60034-1.

International Electrotechnical Commission. Geneva

1996-01-01T23:59:59.000Z

446

E-Print Network 3.0 - ac loss measurement Sample Search Results  

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

Plants 9 Journal of High Speed Networks 13 (2004) 87102 87 An implementation-based comparison of Summary: loss ratio. Using AC-MVE, an algorithm based upon mean and variance...

447

E-Print Network 3.0 - acs survey ix Sample Search Results  

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

67 Institute for Mathematical Physics A-1090 Wien, Austria Summary: Available via WWW.ESI.AC.AT 12;On Higher Analogs of the de Rham Complex Gabriele Vezzosi Via delle...

448

MIT Electric Vehicle Team Porsche designing a cooling system for the AC24 electric motor  

E-Print Network [OSTI]

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 ...

Meenen, Jordan N

2010-01-01T23:59:59.000Z

449

E-Print Network 3.0 - ac stark shifts Sample Search Results  

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

in Figure 3A,C, we uncover the unusually broad higher order Stark line... to electrochromic band shifts which have been analyzed in detail elsewhere.9 The 2 Stark spectrum of...

450

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

SciTech Connect (OSTI)

This report 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 fuel cell buses.

Chandler, K.; Eudy, L.

2007-03-01T23:59:59.000Z

451

E-Print Network 3.0 - ac transmission technology Sample Search...  

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

Jonathan J. Ryder, Martin R. Miller, Andy White, Robert J. Knell and Michael Boots J. J. Ryder (jon.ryder@uea.ac... , Scotland, EH14 4AS. Many host-parasite models...

452

Contract No. DE-AC02-09CH11466 CONTRACT CLAUSES  

E-Print Network [OSTI]

Contract No. DE-AC02-09CH11466 Section I M152 I-i PART II SECTION I CONTRACT CLAUSES TABLE THE GOVERNMENT'S INTEREST WHEN SUBCONTRACTING WITH CONTRACT

Princeton Plasma Physics Laboratory

453

Docket No. EERE-2012-BT-TP-0046; RIN 1904-AC52 Ex partecommunication...  

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

& Publications Docket No. EERE-2012-BT-TP-0046; RIN 1904-AC52 Docket No. EERE-2012-BT-TP-0046 Ex Parte Communication Ex Parte Memorandum on Set Top Boxes and Network Equipment...

454

E-Print Network 3.0 - ac computer-assisted oral Sample Search...  

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

computer-assisted oral Search Powered by Explorit Topic List Advanced Search Sample search results for: ac computer-assisted oral Page: << < 1 2 3 4 5 > >> 1 Page 1 of 3 University...

455

E-Print Network 3.0 - ac underground cable Sample Search Results  

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

i c e s VOICE & DATA Summary: ) The underground cable shall have an aluminium steel polyethylene (ASP) sheath and a core of solid... , transposition and presence of AC voltage. ...

456

System and Battery Charge Control for PV-Powered AC Lighting Systems  

SciTech Connect (OSTI)

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.

Kern, G.

1999-04-01T23:59:59.000Z

457

ac 66-1100 kv: Topics by E-print Network  

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

limits. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise from de Gispert, Adri 403 www.eprg.group.cam.ac.uk...

458

AC 2007-253: ENCOURAGING CREATIVITY IN INTRODUCTORY COMPUTER SCIENCE PROGRAMMING ASSIGNMENTS  

E-Print Network [OSTI]

AC 2007-253: ENCOURAGING CREATIVITY IN INTRODUCTORY COMPUTER SCIENCE PROGRAMMING ASSIGNMENTS Tammy technology, multimedia, software engineering, and CS theory. © American Society for Engineering Education, 2007 #12;Encouraging Creativity in Introductory Computer Science Programming Assignments Abstract

VanDeGrift, Tammy

459

E-Print Network 3.0 - ac electrokinetic funnel Sample Search...  

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

Page: << < 1 2 3 4 5 > >> 1 ME 141C MicroElectroMechanical Systems Introduction to Microfluidics & BioMEMS Summary: Velocimetry Slip flow boundary conditions Analysis of AC...

460

E-Print Network 3.0 - ac electro-osmotic pumps Sample Search...  

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

Ben... September 2006 DOI: 10.1039b608092h AC electro-osmotic (ACEO) pumps in microfluidics currently involve... coatings on the raised and lowered surfaces). However, linear...

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

www.arts.canterbury.ac.nz/internships Project Title: Campaign Assistant: FLUXX: Ideas in  

E-Print Network [OSTI]

and supplier research using the internet and phone, client communication, picking up event equipment(s) for the academic adviser #12;www.arts.canterbury.ac.nz/internships Necessary Qualifications: Major/Minors(s): Coms

Hickman, Mark

462

E-Print Network 3.0 - ac power source Sample Search Results  

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

LEE... , Seoul National University, Seoul, Korea E-mail: jclee9@snu.ac.kr New power combining technique which... in the desired mode without spurious oscillation at other...

463

acs_JZ_jz-2011-01312e 1..6  

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

jz201312e | J. Phys. Chem. Lett. 2011, 2, 2859-2864 LETTER pubs.acs.orgJPCL Supercapacitor Capacitance Exhibits Oscillatory Behavior as a Function of Nanopore Size Guang...

464

On-Orbit Performance of the ACS Solar Blind Channel Hien D. Trana  

E-Print Network [OSTI]

MAMA detector, the ACS/SBC has bright-object limits to protect it from radiation damage. For non the whole detector) limit is optical performance of the SBC is comparable

Johns Hopkins University, Department of Physics and Astonomy, Advanced Camera for Surveys Team

465

Ultrafast High-pressure AC Electro-osmotic Pumps for Portable Biomedical Microfluidics  

E-Print Network [OSTI]

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. ...

Huang, Chien-Chih

466

AC 2010-343: NASA SENIOR DESIGN: MISSION ASSURANCE MANAGEMENT ENVIRONMENT  

E-Print Network [OSTI]

this challenge, we propose to improve spacecraft building and operating processes with integrated software, design, implementation, system integration, validation and test. Identification of System RequirementsAC 2010-343: NASA SENIOR DESIGN: MISSION ASSURANCE MANAGEMENT ENVIRONMENT Jiang Guo, California

Conrad, James M.

467

E-Print Network 3.0 - ac transit fuel Sample Search Results  

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

Sample search results for: ac transit fuel Page: << < 1 2 3 4 5 > >> 1 Hydrogen and Fuel Cell Vehicle Evaluation Richard Parish, Leslie Eudy, and Ken Proc Summary: and the...

468

Variable volume architecture : expanding the boundary  

E-Print Network [OSTI]

Research into the creation of a Variable Volume Architecture is explored through a series of proposals and projects. An argument is established to develop the means and methods of achieving an architecture of transformation. ...

Saheba, Asheshh (Asheshh Mohit), 1972-

2001-01-01T23:59:59.000Z

469

Inserting Group Variables into Fluid Mechanics  

E-Print Network [OSTI]

A fluid, like a quark-gluon plasma, may possess degrees of freedom indexed by a group variable, which retains its identity even in the fluid/continuum description. Conventional Eulerian fluid mechanics is extended to encompass this possibility.

R. Jackiw

2004-10-28T23:59:59.000Z

470

Energy Savings of Variable Speed Motors  

E-Print Network [OSTI]

This paper investigates the energy savings available by utilizing variable speed motors on pump and fan applications. Conventional control of flow or pressure in process plants is normally accomplished by throttling the various streams with control...

Fishel, F. D.

1979-01-01T23:59:59.000Z

471

Variable-Rate State Gasoline Taxes  

E-Print Network [OSTI]

J Bradshaw, "SLate ’F~es’ Gasoline Tax So ~t Wdl Rise," TheVarlable-Rate State Gasoline Taxers Jeffrey Ang-Olson MartinVariable-Rate State Gasoline Taxes Jeffrey Ang-Olson

Ang-Olson, Jeffrey; Wachs, Martin; Taylor, Brian D.

2000-01-01T23:59:59.000Z

472

UselessVariable Elimination Olin Shivers  

E-Print Network [OSTI]

flow analysis on the CPS inter­ mediate form. (I use a CPS representation essentially identical­passing style (CPS) intermediate representations, continuation variables are frequently passed around loops

Shivers, Olin

473

Hybrid permanent magnet and variable reluctance generator  

SciTech Connect (OSTI)

This patent describes a hybrid electrical generator. It comprises: a permanent magnet generator having a permanent magnet rotor mounted on a shaft, the permanent magnet generator providing an output voltage over an operating range which falls in response to an increasing electrical load; a variable reluctance generator having a rotor mounted on the shaft with excitation of a stator of the variable reluctance generator being provided from the permanent magnet generator, the variable reluctance generator providing an output voltage which varies in response to an increasing electrical load over an operating range; and a voltage regulator, responsive to combined output voltages of the generators, for controlling the output voltage provided by the variable reluctance generator.

Vaidya, J.; Belanger, D.J.

1990-09-25T23:59:59.000Z

474

Study of high frequency & low frequency electronic ballasts for HID lamps  

E-Print Network [OSTI]

High-intensity discharge (HID) lamp electronic ballasting is receiving increasing attention in the recent years as low wattage HID lighting systems are finding indoor applications. Advantages of high frequency electronic ballast for HID lamps...

Peng, Hua

1997-01-01T23:59:59.000Z

475

An evaluation of the Panasonic model UD513AC-1 thermoluminescence dosimetry system  

E-Print Network [OSTI]

for the degree of MASTER OF SCIENCE December 1991 Major Subject: Health Physics AN EVALUATION OF THE PANASONIC MODEL UD513AC-I THERMOLUMINESCENCE DOSIMETRY SYSTEM A Thesis by RUSSELL EDWARD DURRER JR. Approved as to style and content by: John W. Poston... (Chair of Committee) Wesl E. Bolch (Member) ilton E. Mc ain (Member) Dan Hig tower (Member) John W. Poston (Head of Department) December 1991 ABSTRACT An Evaluation of the Panasonic Model UD513AC-1 Thermoluminescence Dosimetry System...

Durrer, Russell Edward

2012-06-07T23:59:59.000Z

476

Contract Number: DE-AC05-76RL01830 Modification M881  

E-Print Network [OSTI]

Contract Number: DE-AC05-76RL01830 Modification M881 Part I ­ The Schedule Section F Deliveries) Alternate I (Apr 1984) 1 F ­ 3 Deliverables 2 F ­ i #12;Contract Number: DE-AC05-76RL01830 Modification M881 F ­ 1 Period of Performance This Contract shall be effective as specified in Block No. 3 ­ Effective

477

Contract No. DE-AC02-09CH11466 DELIVERIES OR PERFORMANCE  

E-Print Network [OSTI]

Contract No. DE-AC02-09CH11466 Section F M137 i PART I SECTION F DELIVERIES OR PERFORMANCE TABLE - STOP WORK AND SHUTDOWN AUTHORITY F-5 F.5 - PRINCIPAL PLACE OF PERFORMANCE F-5 #12;Contract No. DE-AC02 [M041 ­ 7/13/10; M137 ­ 10/28/13] (a) The effective performance date of this contract shall begin

Princeton Plasma Physics Laboratory

478

Contract Number: DE-AC05-76RL01830 Modification M881  

E-Print Network [OSTI]

Contract Number: DE-AC05-76RL01830 Modification M881 B-i Part I ­ The Schedule Section B Supplies.......................................................1 #12;Contract Number: DE-AC05-76RL01830 Modification M881 B-1 B­1 Designation of Work in this Contract and as designated in writing from time to time by DOE, including the utilization of information

479

Contract Number: DE-AC05-76RL01830 Modification A508  

E-Print Network [OSTI]

Contract Number: DE-AC05-76RL01830 Modification A508 E-1 Part I ­ The Schedule Section E Inspection) .........................................................................1 E ­ i #12;Contract Number: DE-AC05-76RL01830 Modification A508 E-1 E ­ 1 52.246-9 Inspection the work performed or being performed under the Contract, and the premises where the work is being

480

High-Power Converters and AC Drives IEEE PESC2005 Tutorial  

E-Print Network [OSTI]

@ee.ryerson.ca http://www.ee.ryerson.ca/~bwu/ 2 High-Power Converters and AC Drives 1. Introduction 2. Cascaded H-Bridge Drives · High-Power Semiconductor Devices High-Power Converters and AC Drives Bin Wu 4High · Multilevel Voltage Source Inverters N dC Cascaded H-bridge (CHB) Inverter dC Two Level Inverter dC Flying

Wu, Bin

Note: This page contains sample records for the topic "ac variable frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

@BristolUniLib bristol.ac.uk/library Remote (off-site) access  

E-Print Network [OSTI]

Library @BristolUniLib bristol.ac.uk/library Remote (off-site) access As a member of the University network you may use one of the following options to gain network access from off-site: Remote Desktop.bristol.ac.uk/it-services/ advice/homeusers/remote/studentdesktop. Off-site Proxy The off-site proxy allows use of University web

Bristol, University of

482

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

483

Laser frequency combs for astronomical observations  

E-Print Network [OSTI]

A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require measurements of Doppler velocity drifts of about 1 centimeter per second per year, and astronomical spectrographs have not yet been calibrated to this tolerance. We demonstrate the first use of a laser frequency comb for wavelength calibration of an astronomical telescope. Even with a simple analysis, absolute calibration is achieved with an equivalent Doppler precision of approximately 9 meters per second at about 1.5 micrometers - beyond state-of-the-art accuracy. We show that tracking complex, time-varying systematic effects in the spectrograph and detector system is a particular advantage of laser frequency comb calibration. This technique promises an effective means for modeling and removal of such systematic effects to the accuracy required by future experiments to see direct evidence of the universe's putative acceleration.

Tilo Steinmetz; Tobias Wilken; Constanza Araujo-Hauck; Ronald Holzwarth; Theodor W. Hänsch; Luca Pasquini; Antonio Manescau; Sandro D'Odorico; Michael T. Murphy; Thomas Kentischer; Wolfgang Schmidt; Thomas Udem

2008-09-09T23:59:59.000Z

484

Adaptive frequency comb illumination for interferometry in the case of nested two-beam cavities  

SciTech Connect (OSTI)

The homogeneity test of glass plates in a Fizeau interferometer is hampered by the superposition of multiple interference signals coming from the surfaces of the glass plate as well as the empty Fizeau cavity. To evaluate interferograms resulting from such nested cavities, various approaches such as the use of broadband light sources have been applied. In this paper, we propose an adaptive frequency comb interferometer to accomplish the cavity selection. An adjustable Fabry-Perot resonator is used to generate a variable frequency comb that can be matched to the length of the desired cavity. Owing to its flexibility, the number of measurements needed for the homogeneity test can be reduced to four. Furthermore, compared to approaches using a two-beam interferometer as a filter for the broadband light source, the visibility of the fringe system is considerably higher if a Fabry-Perot filter is applied.

Harder, Irina; Leuchs, Gerd; Mantel, Klaus; Schwider, Johannes

2011-09-01T23:59:59.000Z

485

Time-Frequency Analysis as Probabilistic Inference  

E-Print Network [OSTI]

(see supplementary material). The computational complexity is determined by the cost of the Kalman smoother to be . In practice, optimization of the likelihood by the conjugate gradient algorithm converged far more quickly than alternatives like... -varying) signal-de- pendent adaptation of the representation. Similarly, corruption of a signal by noise or missing samples should introduce uncer- tainty into the values of the time-frequency representation; but again, no unified robust method exists...

Turner, Richard E.

2014-11-06T23:59:59.000Z

486

Possible Enhancement of High Frequency Gravitational Waves  

E-Print Network [OSTI]

We study the tensor perturbations in a class of non-local, purely gravitational models which naturally end inflation in a distinctive phase of oscillations with slight and short violations of the weak energy condition. We find the usual generic form for the tensor power spectrum. The presence of the oscillatory phase leads to an enhancement of gravitational waves with frequencies somewhat less than 10^{10} Hz.

Maria G. Romania; N. C. Tsamis; R. P. Woodard

2011-03-05T23:59:59.000Z

487

Radio frequency (RF) heated supersonic flow laboratory  

SciTech Connect (OSTI)

A unique supersonic flow apparatus which employs an inductively-coupled, radio frequency (RF) torch to supply high enthalpy source gas to the nozzle inlet is described. The main features of this system are the plasma tube, a cooled nozzle assembly, and a combustion/expansion chamber with a heat exchanger. A description of these components with current test data is presented. In addition, a discussion of anticipated experiments utilizing this system is included.

Wantuck, P.; Watanabe, H.

1990-01-01T23:59:59.000Z

488

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

E-Print Network [OSTI]

Ben Williams, Brian Haney, Randall Hunt, Jeff Ellis UtilityBen Williams, Brian Haney, Randall Hunt, Jeff Ellis Utility

Eto, Joseph H.

2011-01-01T23:59:59.000Z

489

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

E-Print Network [OSTI]

2007. Integration of Renewable Resources. Transmissionfor integrating renewable resources on the California ISO-assess the level of renewable resources that can be reliably

Eto, Joseph H.

2011-01-01T23:59:59.000Z

490

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

E-Print Network [OSTI]

that of customer loads alone, which follow a well-understoodequipment and load following) as necessary to follow theused to follow longer variations or trends in load, such as

Eto, Joseph H.

2011-01-01T23:59:59.000Z

491

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

E-Print Network [OSTI]

Load Following regulation and load following), but only to a limited extentregulation and load following), but only to a limited extent

Eto, Joseph H.

2011-01-01T23:59:59.000Z

492

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

E-Print Network [OSTI]

North America Dynamic Wind Generator Modeling Update, Basedperformed by the WECC Wind Generator Modeling Group and theand in particular, wind generators are the primary resources

Eto, Joseph H.

2011-01-01T23:59:59.000Z

493

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

E-Print Network [OSTI]

Report - 2006 Minnesota Wind Integration Study Volume I.NREL). 2010. Eastern Wind Integration and TransmissionAvista Corporation Wind Integration Study. March. http://

Eto, Joseph H.

2011-01-01T23:59:59.000Z

494

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

E-Print Network [OSTI]

in which rapid and extreme wind ramps first depleteoperating conditions involving extreme wind ramping events.records available on extreme wind ramping events and the

Eto, Joseph H.

2011-01-01T23:59:59.000Z

495

Ratchet Effect and Nonlinear Transport for Particles on Random Substrates with Crossed ac Drives  

E-Print Network [OSTI]

We show in simulations that overdamped interacting particles in two dimensions with a randomly disordered substrate can exhibit novel nonequilibrium transport phenomena including a transverse ratchet effect, where a combined dc drive and circular ac drive produce a drift velocity in the direction transverse to the applied dc drive. The random disorder does not break any global symmetry; however, in two dimensions, symmetry breaking occurs due to the chirality of the circular drive. In addition to inducing the transverse ratchet effect, increasing the ac amplitude also strongly affects the longitudinal velocity response and can produce what we term an overshoot effect where the longitudinal dc velocity is higher in the presence of the ac drive than it would be for a dc drive alone. We also find a dynamical reordering transition upon increasing the ac amplitude. In the absence of a dc drive, it is possible to obtain a ratchet effect when the combined ac drives produce particle orbits that break a reflection symmetry. In this case, as the ac amplitude increases, current reversals can occur. These effects may be observable for vortices in type II superconductors as well as for colloids interacting with random substrates.

C. Reichhardt; C. J. Olson Reichhardt

2005-09-13T23:59:59.000Z

496

Comparison of the Unique Mobility and DOE-developed ac electric drive systems  

SciTech Connect (OSTI)

A comparison was made between the most recent DOE-developed AC electric vehicle drive systems and that which is independently under development by Unique Mobility of Golden, Colorado. The DOE-developed AC systems compared in this study are the Single-Shaft Electric Propulsion System (ETX-II) developed by Ford Motor Company and the General Electric Company under contract number DE-AC07-85NV10418, the Dual-Shaft Electric Propulsion (DSEP) System developed by Eaton Corporation under contract number DOE-AC08-84NV-10366, and the anticipated results of the Modular Electric Vehicle (MEV) system currently being developed by Ford and General Electric under contract number DE-AC07-90ID13019. The Unique Mobility brushless DC electric vehicle drive system represents their latest electric drive technology and is being developed in cooperation with BMW Technik Gmbh of Germany. Comparisons of specific volume, specific weight, efficiency and expected vehicle performance are made of the different systems based upon measured system performance data where available. One conclusion presented is that the Unique Mobility drive system under development with BMW appears to provide comparable performance to the AC systems studied.

Cole, G.H.

1993-01-01T23:59:59.000Z

497

Numerical study of the effect of normalised window size, sampling frequency, and noise level on short time Fourier transform analysis  

SciTech Connect (OSTI)

Photonic Doppler velocimetry, also known as heterodyne velocimetry, is a widely used optical technique that requires the analysis of frequency modulated signals. This paper describes an investigation into the errors of short time Fourier transform analysis. The number of variables requiring investigation was reduced by means of an equivalence principle. Error predictions, as the number of cycles, samples per cycle, noise level, and window type were varied, are presented. The results were found to be in good agreement with analytical models.

Ota, T. A. [AWE, Aldermaston, Reading, Berkshire RG7 4PR (United Kingdom)] [AWE, Aldermaston, Reading, Berkshire RG7 4PR (United Kingdom)

2013-10-15T23:59:59.000Z

498

Cloud speed impact on solar variability scaling â?? Application to the wavelet variability model  

E-Print Network [OSTI]

Kleissl, J. , 2013. Deriving cloud velocity from an array ofCloud Speed Impact on Solar Variability Scaling -this work, we determine from cloud speeds. Cloud simulator

Lave, Matthew; Kleissl, Jan

2013-01-01T23:59:59.000Z

499

System and method for monitoring and controlling stator winding temperature in a de-energized AC motor  

DOE Patents [OSTI]

A system and method for measuring and controlling stator winding temperature in an AC motor while idling is disclosed. The system includes a circuit having an input connectable to an AC source and an output connectable to an input terminal of a multi-phase AC motor. The circuit further includes a plurality of switching devices to control current flow and terminal voltages in the multi-phase AC motor and a controller connected to the circuit. The controller is configured to activate the plurality of switching devices to create a DC signal in an output of the motor control device corresponding to an input to the multi-phase AC motor, determine or estimate a stator winding resistance of the multi-phase AC motor based on the DC signal, and estimate a stator temperature from the stator winding resistance. Temperature can then be controlled and regulated by DC injection into the stator windings.

Lu, Bin (Kenosha, WI); Luebke, Charles John (Sussex, WI); Habetler, Thomas G. (Snellville, GA); Zhang, Pinjia (Atlanta, GA); Becker, Scott K. (Oak Creek, WI)

2011-12-27T23:59:59.000Z

500

X-ray variability of SS433: effects of the supercritical accretion disc  

E-Print Network [OSTI]

We study a stochastic variability of SS433 in the $10^{-4} - 5\\times 10^{-2}$ Hz frequency range based on RXTE data, and on simultaneous observations with RXTE and optical telescopes. We find that the cross-correlation functions and power spectra depend drastically on the precession phase of the supercritical accretion disc. When the wind funnel of the disc is maximally open to the observer, a flat part emerges in the power spectrum; a break is observed at the frequency $1.7\\times10^{-3}$ Hz, with a power-law index $\\beta \\approx 1.67$ at higher frequencies. The soft emission forming mostly in the jets, lags behind the hard and optical emission. When the observer does not see the funnel and jets (the `edge-on' disc), the power spectrum is described by a single power-law with $\\beta \\approx 1.34$ and no correlations between X-ray ranges are detected. We investigated two mechanisms to explain the observed variability at the open disc phase, 1) reflection of radiation at the funnel wall (X-rays and optical) and ...

Atapin, Kirill; Medvedev, Aleksei; Vinokurov, Alexander

2014-01-01T23:59:59.000Z