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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,
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.


1

Variable Frequency AC Drives for Cooling Tower Energy Efficiency  

E-Print Network (OSTI)

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... of individual cell air streams is ineffective due to one or more of the following: --Partitions are missing. --Partitions are incomplete. This condition results in temperature control problems. For example, if constant CWT is desired, and no means...

Corey, R. W.

1982-01-01T23:59:59.000Z

2

Variable Frequency Drives  

NLE Websites -- All DOE Office Websites (Extended Search)

How BPA Supports VFDs Rebates are available from your utility for Variable Frequency Drives on pumps 20hp or greater and storage fans.. Energy savings from VFDs vary and can...

3

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.

4

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

5

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

6

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

7

6 - Control systems for AC variable speed drives  

Science Journals Connector (OSTI)

Publisher Summary This chapter explores the control system, embodied in the control circuits. The simplest method of providing auxiliary power to the converter control circuits is from an auxiliary transformer connected to the mains. The primary need for current feedback in general purpose variable speed drives (VSDs) is inverter switching device protection. Various disadvantages of the vector controlled AC drive as compared to a DC drive are discussed in the chapter. The strategy of an AC vector control drive is to calculate the individual current vectors to eventually enable separate control of the flux current and the torque current under all speed and load conditions. The power circuit for a vector converter is almost identical to that used by a variable voltage variable frequency (VVVF) drive. High accuracy motor current feedback is also necessary to provide control of motor torque. DC bus current feedback is suitable for switching device protection and current limiting in most AC VSDs. Analog speed transducers are increasingly being replaced by digital devices, which are more compatible with modern digital control systems.

Malcolm Barnes

2003-01-01T23:59:59.000Z

8

INSTALLATION, COMMISSIONING AND TROUBLE SHOOTING OF VARIABLE FREQUENCY DRIVE.  

E-Print Network (OSTI)

??In this thesis, the installation of variable frequency drive on board a ship is introduced briefly. In this particular study the variable frequency drive was… (more)

Kuituniemi, Santtu

2013-01-01T23:59:59.000Z

9

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

SciTech Connect

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

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.

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

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.

1998-09-08T23:59:59.000Z

12

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

13

Chapter 18: Variable Frequency Drive Evaluation Protocol  

SciTech Connect

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

14

Soft switched high frequency ac-link converter  

E-Print Network (OSTI)

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

Balakrishnan, Anand Kumar

2009-05-15T23:59:59.000Z

15

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

16

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

17

System for transmitting 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 in selected to be within the response band of the FM transmitter. The FM modulated carrier signal is received by an FM receiver coupled to the AC power line, demodulated and the demodulated signal frequency is converted by a frequency-to-voltage converter back to the form of the original low frequency analog input signal.

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

1989-01-01T23:59:59.000Z

18

Present and Future Modes of Low Frequency Climate Variability  

SciTech Connect

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

19

Variable Frequency Drives: Energy Savings and Impact on Motor Performance  

E-Print Network (OSTI)

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

Petro, D.

20

Conservation Theory Process Control Using Variable Frequency Drives  

E-Print Network (OSTI)

The purpose of this paper is to outline some of the economic considerations of variable frequency control and to point out possible applications in order to create greater awareness of the options available to the engineer as he develops new...

Myers, N. S.

1980-01-01T23:59:59.000Z

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.


21

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

22

High-frequency equivalent model of AC motor for electric vehicle drive system  

Science Journals Connector (OSTI)

The application of the motor drive system in electric and hybrid-electric vehicles can lead to a significant increase in electromagnetic compatibility. The AC motor as an important part of motor drive system must be considered. In this paper, a high frequency modelling method of the AC motor is presented. The modelling method consists of deriving the motor model parameters from mathematical resolution of the electrical circuit equations and observation of the variations of the motor impedance with the frequency. All parameters of the proposed models are obtained by differential mode (DM) and common mode (CM) impedance measurement in the frequency domain. The model is verified by impedance measurement of a synchronous motor. The method proposed can be used to obtain a high-frequency equivalent circuit of an AC motor and predict conducted electromagnetic interference in a motor drive system.

Yongming Yang; Hemeng Peng; Quandi Wang

2013-01-01T23:59:59.000Z

23

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

24

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

25

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

26

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

E-Print Network (OSTI)

-to-ac converter eliminating the acto-dc rectification stage, power factor correction boost stage, and dc-dc converter stage present in the conventional system. The output of the high-frequency isolation transformer is rectified and processed via a filtering stage...

Sulistyono, Widodo

2012-06-07T23:59:59.000Z

27

High efficiency pool filtering systems utilising variable frequency drives  

Science Journals Connector (OSTI)

Over 1 year, private swimming pools in Australia will typically consume 1680 GWh of electricity, producing 2130 kt of CO2. Redesigning a pool's filtration system and using it more efficiently can reduce the energy use, and hence the CO2 production, by a significant amount. This paper describes experimental measurements carried out on a new design of pool pump system. Initial experiments using a variable frequency drive (VFD) with a standard, single phase pump/motor system have achieved energy savings of 40%. Utilising a VFD and a three phase pump/motor energy savings of 61% have been achieved, without degrading the system performance.

Z. Hameiri; T. Spooner; A.B. Sproul

2009-01-01T23:59:59.000Z

28

Efficient Energy Management: Is Variable Frequency Drives the Solution  

Science Journals Connector (OSTI)

Abstract Over the last few years the cost of power electricity has increased significantly. Researchers and manufacturers of electrical goods have been trying to find ways to minimize the use of power electricity while maintaining the efficiency of electrical equipments. To provide efficient energy management for today's market, manufacturers are now turning to a technology known as variable frequency drives (VFDs). \\{VFDs\\} are being used for various equipments ranging from small electrical appliances to the largest of mine mill drives and compressors. Household air conditioning compressors, for example, are not short of running on VFD technology. This concept paper will discuss the alternative use of this energy.

Nasir Khalid

2014-01-01T23:59:59.000Z

29

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

30

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… (more)

Han, Xu

2012-01-01T23:59:59.000Z

31

Variable optical attenuator with a polymer-stabilized dual-frequency liquid crystal  

E-Print Network (OSTI)

Variable optical attenuator with a polymer-stabilized dual-frequency liquid crystal Yung-Hsun Wu. For the DFLC-based homogeneous cell, we use a low- frequency 1 kHz electric field to drive the VOA and a high-frequency, Xiao Liang, Yan-Qing Lu, Fang Du, Yi-Hsin Lin, and Shin-Tson Wu A transmission-type variable optical

Wu, Shin-Tson

32

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

33

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

34

Vacuum electron acceleration by using two variable frequency laser pulses  

SciTech Connect

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

35

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

36

Electro-Thermal Dynamics and the Effects of Generalized Discontinuous Pulse Width Modulation Algorithms on High Performance Variable Frequency Drives.  

E-Print Network (OSTI)

??This thesis is concerned with issues observed with the variable frequency drive, VFD, traction inverter used in the Buckeye Bullet 3 as it performed during… (more)

Krohn, Austin Bengoechea

2014-01-01T23:59:59.000Z

37

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

SciTech Connect

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

38

Extinction risk and eco-evolutionary dynamics in a variable environment with increasing frequency of extreme events  

Science Journals Connector (OSTI)

...35] found that in a variable environment extinction...accompanied by an increased frequency of climate and point...accompanied by an increased frequency of climate and point...a continuous climate variable, such as mean of summer...climate trend mostly drives the shift of the phenotype...

2014-01-01T23:59:59.000Z

39

The variability of high-frequency acoustic backscatter from the region near the sea surface  

Science Journals Connector (OSTI)

The temporal variability of acoustic backscattering from the region near the sea surface is examined for frequencies in the 30–70 kHz range. A variance spectrum of the scattering strength exhibits effects associated with three different processes. Below about 0.1 Hz the spectrum contains a large contribution associated with temporal variations in the advection of bubble clouds through the measurement volume by large-scale processes. At high frequencies the spectrum asymptotes to a level characteristic of a Gaussian backscatteredpressure field from randomly moving bubbles within the scattering volume. The overall variability is treated as a slow modulation of this Gaussian process by larger-scale processes and a probability density function is derived for the scattering strength using Bayes’ theorem. Finally in some cases the spectrum exhibits a peak at the frequency of the dominant surface waves. Attempts to compute coherence functions between the backscattered acoustic power and surface wave orbital velocities measured by a microwave system observing the same spot as the acoustic system resulted in very low values. This leads to the belief that the wave-induced peak in the acoustic backscatter variance spectrum is caused by highly nonlinear processes. A time series of acoustic backscatter from a vertically pointing system confirms the existence of this modulation at the dominant wave frequency and also suggests its nonlinear character.

Peter H. Dahl; William J. Plant

1997-01-01T23:59:59.000Z

40

AC Ward Leonard drive systems: Revisiting the four-quadrant operation of AC machines  

Science Journals Connector (OSTI)

Abstract In this paper, the problem of controlling the speed of AC machines in four quadrants is revisited from a completely new viewpoint, based on the idea of powering an AC machine with a synchronous generator that generates a variable-voltage–variable-frequency supply. This is a natural, mathematical, but not physical, extension of the conventional Ward Leonard drive systems for DC machines to AC machines. As a result, AC drives can be regarded as generator-motor systems, which facilitate the analysis of AC drives and the introduction of other special functions because a system consisting of a generator and a motor is easier to be handled than the conventional AC drive that consists of an inverter and a motor. Control strategies, with and without a speed sensor, are proposed to implement this idea and the experimental results are presented to demonstrate the feasibility.

Qing-Chang Zhong

2013-01-01T23:59:59.000Z

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.


41

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

SciTech Connect

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

42

Effect of Cyclotron Resonance Frequencies in Particles Due to AC and DC Electromagnetic Fields  

E-Print Network (OSTI)

and Environmental Engineering, The University of Melbourne, VIC 3010, Australia Department of Electrical and Electronic Engineering, University of Peradeniya, Peradeniya, Srilanka Email: malka and ion cyclotron resonance (ICR) frequencies which is derived from ionic charge to mass ratio is evident

Halgamuge, Malka N.

43

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

E-Print Network (OSTI)

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

Amirabadi, Mahshid

2013-08-07T23:59:59.000Z

44

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

45

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

46

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

47

A review on sensorless techniques for sustainable reliablity and efficient variable frequency drives of induction motors  

Science Journals Connector (OSTI)

Abstract Variable frequency drives (VFDs) can provide reliable dynamic systems and significant savings in energy usage and costs of the induction motors (IMs). Sensorless controlled IM drives have advantages in terms of efficiency enhancement and energy savings for critical applications such as electric vehicles, high performance machine tools, fans, compressors, etc. IM drives without having speed sensors or optical encoders mounted at the motor shaft are attractive because of their lower cost and higher reliability. When mechanical speed sensor is removed, the rotor speed information is estimated using the measured quantities of stator voltages and currents at the IM terminals. This paper highlights the sensorless techniques applied to the IM drives for sustainable reliability and energy savings. Overview on the IM mathematical model is briefly summarized to establish a physical basis for the sensorless schemes used. Further, the different types of IM-VFDs are presented in the paper. The main focus of this review is on the sensorless estimation techniques which are being applied to make IM-VFDs more effective during wide speed operations including very-high and very-low speed regions.

Ibrahim M. Alsofyani; N.R.N. Idris

2013-01-01T23:59:59.000Z

48

Effect on energy use and greenhouse microclimate through fan motor control by variable frequency drives  

Science Journals Connector (OSTI)

A comparison was conducted between ON–OFF and variable frequency drive (VFD) systems to control greenhouse ventilation fans. The study aimed to determine the effect of each system on the energy consumption and resulting greenhouse microclimate. The experiments were conducted in a commercial size greenhouse in which pepper was grown. To check the performance of the fan that was controlled by a VFD system, it was installed in a test facility and operated under several rotation speeds. At each speed of rotation, the static pressure on the fan was changed and parameters, such as electricity consumption and air flow rate, were measured. Reducing the fan speed with the VFD system resulted in reductions in the air flow rate through the greenhouse and energy consumption, the latter being much more significant. The study showed that VFD control can reduce electricity consumption compared with ON–OFF operation by an amount that depends on the weather. In the present study, the average energy consumption with the VFD control system over a period of one month, was about 0.64 of that with an ON–OFF system. The average greenhouse daily air temperatures and humidity ratios obtained with each control system between 0700 and 1800 were nearly equal during that month. The results obtained in the greenhouse further show that the VFD system has a greater potential than the ON–OFF to reduce the range of amplitude variations in the air temperature and humidity ratio within the greenhouse.

Meir Teitel; Yun Zhao; Moti Barak; Eli Bar-lev; David Shmuel

2004-01-01T23:59:59.000Z

49

Variable frequency drives for MSF desalination plant and associated pumping stations  

Science Journals Connector (OSTI)

Power Electronic Variable Frequency Drives (VFD) are a well proven, reliable and cost efficient solution to ensure precise control of torque and speed of electrically driven rotating machines (such as pumps, compressors, fans, extruders etc.) in a wide range of industrial process. For the purpose of pumps applications, if compared to conventional mechanical flow regulation systems (vanes, gearbox, hydraulic coupling etc.) VFD provides the advantages of more efficient energy management as well as better accuracy and flexibility in process control. Latest technologies in silicon power devices, microprocessors and software development allowed remarkable improvements in performances, reliability and cost reduction; as a consequence energy savings due to VFD use are ensuring investment pay back in a very short time. After a quick summary about basic concepts on VFD for fluid flow control and a short description of different VFD’s topologies presently available, special attention is focused on a recent application for pump in a MSF desalination, as well as in other applications in pumping stations for water transmission systems associated to desalination plants.

Roberto Camoirano; Giuseppe Dellepiane

2005-01-01T23:59:59.000Z

50

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.

51

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.

52

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

SciTech Connect

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

53

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

54

The Spectrum and Frequency of Self-Inflicted and Host Gene Mutations Produced by the Transposon Ac in Maize  

Science Journals Connector (OSTI)

...responsible for distribution of materials integral to the findings presented...Various Ac Mutations. The diagrams illustrate DNA replication...pairwise-deletion option for handling gaps. Accession Numbers Sequence...Supplemental Data The following materials are available in the online...

Jun T. Huang; Hugo K. Dooner

2012-10-30T23:59:59.000Z

55

Energy saving in agricultural buildings through fan motor control by variable frequency drives  

Science Journals Connector (OSTI)

A comparison was conducted between ON–OFF and variable frequency drive (VFD) systems to control ventilation fans of greenhouses and poultry houses. The study aimed to determine the effect of each system on the energy consumption and resulting microclimate within the houses. The experiments were carried out in a commercial-size greenhouse in which pepper was grown and in commercial poultry houses. Reducing the fan speed with the VFD system resulted in reductions in the airflow rate through the houses and energy consumption, the latter being much more significant. The study showed that VFD control can reduce electricity consumption compared with ON–OFF operation. In the present study, the average energy consumption with the VFD control system was about 0.64 and 0.75 of that with an ON–OFF system in the greenhouse and poultry houses, respectively. The average greenhouse daily air temperatures and humidity ratios obtained with each control system between 07:00 and 18:00 were nearly equal. The results obtained in the greenhouse further showed that the VFD system has a greater potential than the ON–OFF, to reduce the range of amplitude variations in the air temperature and humidity ratio within the greenhouse. The average air temperatures over day and night, in the poultry houses, with each control system were nearly equal. The relative humidity, however, was slightly lower with VFD than with ON–OFF. Reductions in the range of amplitude variations of the air temperature and humidity were also observed in the poultry houses.

Meir Teitel; Asher Levi; Yun Zhao; Moti Barak; Eli Bar-lev; David Shmuel

2008-01-01T23:59:59.000Z

56

Techno-economic feasibility study of providing variable frequency drive for high pressure pump, SWRO plant at NDDP, Kalpakkam  

Science Journals Connector (OSTI)

The cost of product water is a key factor in determination of acceptability of any desalination system and plant. In case of Sea Water Reverse Osmosis plants, most of the energy consumed is in the form of electricity. The High Pressure Pump (HPP) is the single major energy consuming equipment with a share of above 75%. Hence reduction in energy consumed by HPP will have a substantial effect on the overall energy consumption. The high starting torque requirement of high pressure pump results in increased acceleration time of the motor which subsequently increases the strain on the upstream electrical system from motor feeder to transformer. Provision of a Variable Frequency Drive can be a solution for both the above problems. This paper studies the techno-economic feasibility of providing variable frequency drive for HPP motor at NDDP, Kalpakkam.

R. Nagaraj; V. Murugan; Ashok Y. Dangore; K.L. Thalor; S. Prabakar; V.K. Srivastava; P.K. Tewari

2010-01-01T23:59:59.000Z

57

High-Frequency Variability in Hurricane Power Dissipation and Its Relationship to Global Temperature  

Science Journals Connector (OSTI)

The power dissipation of Atlantic tropical cyclones has risen dramatically during the last decades and the increase is correlated with an increase in the underlying sea surface temperature (SST) at low (decadal) frequencies. Because of the large ...

James B. Elsner; Anastasios A. Tsonis; Thomas H. Jagger

2006-06-01T23:59:59.000Z

58

Electrochimica Acta 51 (2005) 943951 Tin oxide nanosensor fabrication using AC dielectrophoretic  

E-Print Network (OSTI)

into the microchannel. An alternating (AC) voltage of 9.8 V peak to peak, with variable frequency, was applied between, Room 321 Love Building, 771, Ferst Drive, Atlanta, GA 30332, USA b School of Materials Science a Maxwell­ Wagner interfacial polarization at a frequency determined by the relationship between the complex

Wang, Zhong L.

59

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

SciTech Connect

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

60

Spatial and temporal variability of the frequency of extreme daily rainfall regime in the La Plata Basin during the 20th century  

Science Journals Connector (OSTI)

We analyzed trends, interdecadal variability, and the quantification of the changes in the frequency of daily rainfall for two thresholds: 0.1 mm and percentile 75th, using high quality daily series from 52 st...

Olga C. Penalba; Federico A. Robledo

2010-02-01T23:59:59.000Z

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

An AChBKr315M2BU3 induction variable-frequency electric motor with a squirrel-cage rotor  

Science Journals Connector (OSTI)

Information about a variable-frequency electric motor designed and manufactured by OAO NIPTIEM is presented. The motor is intended for use as a starter motor for the GTU-8 gas turbine power...

M. F. Zapadnya; O. V. Martynov; S. V. Piskunov…

2007-06-01T23:59:59.000Z

62

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

63

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

E-Print Network (OSTI)

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

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

2013-01-01T23:59:59.000Z

64

Measurable energy savings of installing variable frequency drives for cooling towers’ fans, compared to dual speed motors  

Science Journals Connector (OSTI)

Abstract In recent years the building management system (BMS) controllers have been used to control the operation of heating, ventilation, and air conditioning system in addition to lighting and some electrical equipment in order to save energy. In the water cooled system, the BMS controls the operation process of the cooling towers (CTs) fans of dual speed motors to maintain a constant leaving water temperature for different cooling loads and different ambient wet bulb temperature (WBT). This paper presents the effect of installing variable frequency drives (VFDs) for \\{CTs\\} fans in Kuwait during summer season on energy savings compared to dual speed control. The results have shown that with VFD mode, the reduction in water consumption was over 13% compared to the commonly used dual speed mode. More importantly, the combined power for the chillers and the \\{CTs\\} fans for the same amount of cooling produced were reduced by 5.8% in the VFD mode.

E. Al-Bassam; R. Alasseri

2013-01-01T23:59:59.000Z

65

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

66

The frequency dependent impedance of an HVdc converter  

SciTech Connect

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

67

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

E-Print Network (OSTI)

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

Eto, Joseph H.

2011-01-01T23:59:59.000Z

68

A techno-economic analysis of cost savings for retrofitting industrial aerial coolers with variable frequency drives  

Science Journals Connector (OSTI)

A techno-economic model was created in order to develop curves that show the typical annual energy savings, rate of return, and payback for retrofitting aerial coolers with variable frequency drives (VFDs) for up to 50 motors, motor sizes from 4 to 186 kW (5–250 hp), and varying climate conditions. The cost savings due to installing a VFD depends on the reduction in energy used, as well as the reduction in power demand, the capital cost of the VFD, installation cost of the VFD, change in operating cost, and cost of electricity. The geographic locations examined in this report were Fort McMurray, Calgary, Vancouver, and Thunder Bay. This study found that the IRR increases rapidly with motor size, becomes greater than 10% at a motor size of approximately 15 kW, and may be as high as 220% (for the case of fifty, 186 kW motors). The IRR is sensitive to the number of fan motors retrofitted with VFDs, however the sensitivity rapidly declines as the number of motors is increased beyond five. The simple payback period becomes less than 1 year and nearly independent of number of motors and motor size for motors larger than 90 kW. Ambient temperature and geographic location affect the profitability of the investment, although the IRR only changes by approximately 4%.

Patrick Miller; Babatunde Olateju; Amit Kumar

2012-01-01T23:59:59.000Z

69

Development and application of setup for ac magnetic field in neutron scattering experiments  

SciTech Connect

We report on a new setup developed for neutron scattering experiments in periodically alternating magnetic fields at the sample position. The assembly consisting of rf generator, amplifier, wide band transformer, and resonance circuit. It allows to generate homogeneous ac magnetic fields over a volume of a few cm{sup 3} and variable within a wide range of amplitudes and frequencies. The applicability of the device is exemplified by ac polarized neutron reflectometry (PNR): a new method established to probe remagnetization kinetics in soft ferromagnetic films. Test experiments with iron films demonstrate that the ac field within the accessible range of frequencies and amplitudes produces a dramatic effect on the PNR signal. This shows that the relevant ac field parameters generated by the device match well with the scales involved in the remagnetization processes. Other possible applications of the rf unit are briefly discussed.

Klimko, Sergey [Laboratoire Leon Brillouin, 91191 Gif-sur-Yvette (France); Zhernenkov, Kirill; Toperverg, Boris P.; Zabel, Hartmut [Institut fuer Festkoerperphys IV, Ruhr Universitaet Bochum, D-44780 Bochum (Germany)

2010-10-15T23:59:59.000Z

70

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

71

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

72

Theoretical model for evaluation of variable frequency drive for cooling water pumps in sea water based once through condenser cooling water systems  

Science Journals Connector (OSTI)

In sea water based once through cooling water system for power plants, sea water is pumped through the condenser and the return hot water is let back to sea. The cooling water pumps (CWP) in power plants generally operate at constant speed, pumping variable quantities of water depending on the tide level in the sea. The variable flow causes variation in condenser back pressure resulting in changes in the turbine cycle heat rate. If the pump speed is controlled using a variable frequency drive (VFD) to maintain design flow irrespective of the tide level, the CWP power consumption can be reduced compared to the case with constant speed CWP. However, the turbine cycle heat rate benefit that could have accrued at tide levels above the pre defined level (for fixing the CWP head) with constant speed CWP would have to be sacrificed. This paper provides a theoretical model with a typical case study to establish viability of providing VFD for \\{CWPs\\} in power plants with sea water based once through condenser cooling water system.

R. Harish; E.E. Subhramanyan; R. Madhavan; S. Vidyanand

2010-01-01T23:59:59.000Z

73

AC | OpenEI  

Open Energy Info (EERE)

AC AC Dataset Summary Description The following data-set is for a benchmark residential home for all TMY3 locations across all utilities in the US. The data is indexed by utility service provider which is described by its "unique" EIA ID ( Source National Renewable Energy Laboratory Date Released April 05th, 2012 (2 years ago) Date Updated April 06th, 2012 (2 years ago) Keywords AC apartment CFL coffeemaker Computer cooling cost demand Dishwasher Dryer Furnace gas HVAC Incandescent Laptop load Microwave model NREL Residential television tmy3 URDB Data text/csv icon Residential Cost Data for Common Household Items (csv, 14.5 MiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Annually Time Period License License Open Data Commons Public Domain Dedication and Licence (PDDL)

74

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

SciTech Connect

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

75

AC Transit  

Energy.gov (U.S. Department of Energy (DOE))

AC Transit (or the Alameda-Contra Costa Transit District) is based in Oakland, California, and provides transportation services to the East Bay of San Francisco. The 360-square-mile service area includes 13 cities and adjacent unincorporated areas in Alameda and Contra Costa counties. AC Transit's approximately 638 vehicles serve more than 65 million annual passengers.

76

Quantum theory of optical temporal phase and instantaneous frequency. II. Continuous-time limit and state-variable approach to phase-locked loop design  

SciTech Connect

We consider the continuous-time version of our recently proposed quantum theory of optical temporal phase and instantaneous frequency [M. Tsang et al., Phys. Rev. A 78, 053820 (2008)]. Using a state-variable approach to estimation, we design homodyne phase-locked loops that can measure the temporal phase with quantum-limited accuracy. We show that postprocessing can further improve the estimation performance if delay is allowed in the estimation. We also investigate the fundamental uncertainties in the simultaneous estimation of harmonic-oscillator position and momentum via continuous optical phase measurements from the classical estimation theory perspective. In the case of delayed estimation, we find that the inferred uncertainty product can drop below that allowed by the Heisenberg uncertainty relation. Although this result seems counterintuitive, we argue that it does not violate any basic principle of quantum mechanics.

Tsang, Mankei; Shapiro, Jeffrey H. [Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Lloyd, Seth [Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2009-05-15T23:59:59.000Z

77

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

78

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

79

Digital ac monitor  

DOE Patents (OSTI)

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

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

1987-06-09T23:59:59.000Z

80

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

E-Print Network (OSTI)

However, the NCC has the following disadvantages, 1. very limited(fow) output frequency range 2. subharmonics are generated at input and output side 3. poor input power factor These disadvantages can be overcome by employing forced commutated bidirec... diode sre connected anti-series. The main objectives of this thesis are summarized as follows, 1. Study and analysis of direct ac to ac matrix power converters. 2. Preseiitation of a new PWM control strategy to selectively eliminate unwanted lower...

Choi, Sewan

2012-06-07T23:59:59.000Z

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

M2ACS | M2ACS Web Space  

NLE Websites -- All DOE Office Websites (Extended Search)

Welcome to the Multifaceted Mathematics for Complex Energy Systems (M2ACS) Welcome to the Multifaceted Mathematics for Complex Energy Systems (M2ACS) project webspace We are a multi-institution project whose aim is to fully explore the opportunities in applied mathematics brought about by multi-disciplinary focus - involving optimization, dynamical systems, stochastic analysis, discrete mathematics, scalable algorithms - on the DOE Grand Challenge of energy systems. The central research concept is the one of multi-faceted mathematics - whereby new mathematics is discovered by sustained investigation of the multiple facets presented by the grand challenge subproblems, such as nonconvexity, stochasticity, integrality, spatio-temporal variability - from the perspective of all the mathematics discipline area involved. Our project involves 22 principal investigators from 3 national

82

Accommodation & ACS Advertising Policy  

E-Print Network (OSTI)

Accommodation & Campus Services. ACS Advertising Policy This paper states the University department Accommodation & Campus Services' (ACS) policy on advertising, sponsorship and promotions and any restrictions. Accommodation & Campus Services, the Students' Union, all affiliated bodies and advertisers are expected

Stevenson, Mark

83

ACS-GDCh ALLIANCE  

Science Journals Connector (OSTI)

ACS-GDCh ALLIANCE ... Other aspects of the strategic collaboration alliance will identify additional activities and services that could be mutually beneficial to both ACS and GDCh members, in keeping with both organizations’ strategic goals. ...

MADELEINE JACOBS

2010-09-20T23:59:59.000Z

84

Anisotropic high temperature superconductors as variable resistors and switches  

SciTech Connect

Several anisotropic high temperature superconductors show critical current densities which are strongly dependent on the direction of an applied external magnetic field. The resistance of a sample can change by several orders of magnitude by applying a magnetic field. The potential for using the field dependent variable resistor or switch for applications in power systems is evaluated. Test results with small samples are presented. The requirements for large scale applications are outlined. The magnetic field triggering requirement, the frequency response of the device, use in 60 Hz ac circuits and heat transfer consideration are investigated. Several application examples are discussed. Use of variable resistor as a fault current limiter, as a switching element in rectifier circuitry and as an improved dump resistor for a superconducting magnet is presented.

Boenig, H.J.; Daugherty, M.A.; Fleshler, S.; Maley, M.P.; Mueller, F.M.; Prenger, F.C.; Coulter, J.Y.

1994-12-01T23:59:59.000Z

85

The Nova-Likes Ac Cnc, Rw Tri, Ux Uma and the Nova Dq Her: Common and Different Properties  

Science Journals Connector (OSTI)

An analysis of the main photometric properties of the nova-like variables AC Cnc, RW Tri and UX UMa, and...

E. S. Dmitrienko

1996-01-01T23:59:59.000Z

86

Celebrate Earth Day with ACS  

Science Journals Connector (OSTI)

Celebrate Earth Day with ACS ... Winners of the ACS-sponsored Earth Day 2004 music video contest are reported. ... ACS resources for celebrating the Earth Day 2005 theme, "Air—Here, There, Everywhere", are discussed. ...

Erica K. Jacobsen

2005-03-01T23:59:59.000Z

87

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

88

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

89

Solutions for Interharmonics in Variable Speed Drives for LNG Plants:.  

E-Print Network (OSTI)

??Variable speed drives can cause components of any frequency known as interharmonics. Large variable speed drives in the order of tens of megawatts can replace… (more)

Verhulst, M.P.A.

2011-01-01T23:59:59.000Z

90

Diversity–disturbance relationships: frequency and intensity interact  

Science Journals Connector (OSTI)

...relationship depended on the frequency of disturbances by the...diversity as the response variable and frequency and intensity as factors...unequivocally that the frequency-intensity interaction drives the coexistence of ecologically...

2012-01-01T23:59:59.000Z

91

Neotyphodium endophyte infection frequency in annual grass populations: relative importance of mutualism and transmission efficiency  

Science Journals Connector (OSTI)

...equilibrium infection frequency, even if infected...equilibrium infection frequency (see also Ravel...should be expected to drive the patterns of endophyte infection frequency. Variability in...environmental factors, variable proportions of viable...

2008-01-01T23:59:59.000Z

92

On the decadal and interdecadal variability in the Pacific Ocean  

Science Journals Connector (OSTI)

The Pacific decadal and interdecadal oscillation (PDO) has ... is a long-lived ENSO-like pattern of Pacific climate variability with a period of 10– ... warm (cool) SSTs in the central North Pacific are always ac...

Yang Haijun; Zhang Qiong

2003-01-01T23:59:59.000Z

93

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

94

Vibrational, giant dielectric and AC conductivity properties of agglomerated CuO nanostructures  

Science Journals Connector (OSTI)

We report frequency, temperature dependent dielectric response and AC conductivity of nanocrystalline CuO. These nanoparticles were prepared using sol–gel technique. Prepared particles were made as a pellet us...

K. R. Deepthi; T. Pandiyarajan…

2013-03-01T23:59:59.000Z

95

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

96

ACS | Open Energy Information  

Open Energy Info (EERE)

ACS ACS Jump to: navigation, search Name ACS Place Madrid, Spain Zip 28036 Sector Solar Product Madrid based construction company involved in the development of solar thermal projects. Coordinates 40.4203°, -3.705774° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":40.4203,"lon":-3.705774,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

97

ETA-AC002  

NLE Websites -- All DOE Office Websites (Extended Search)

2 2 Revision 2 Effective March 1, 1997 "Control of Test Conduct" Prepared by Electric Transportation Applications Prepared by: _______________________________ Date:__________ Jude M. Clark Approved by: _________________________________________________ Date: _______________ Donald B. Karner Procedure ETA-AC002 Revision 2 2 ©1997 Electric Transportation Applications All Rights Reserved TABLE OF CONTENTS 1.0 Objectives 3 2.0 Purpose 3 3.0 Documentation 3 4.0 Initial Conditions and Prerequisites 4 5.0 Personnel Qualifications 5 6.0 Activity Requirements 6 7.0 Supplemental Activity Requirements 8 8.0 Glossary 9 9.0 References 10 Procedure ETA-AC002 Revision 2 3 ©1997

98

ETA-AC006  

NLE Websites -- All DOE Office Websites (Extended Search)

6 6 Revision 2 Effective: March 1, 1997 Vehicle Verification Prepared by Electric Transportation Applications Prepared by: _______________________________ Date:__________ Jude M. Clark Approved by: _________________________________________________ Date: ______________ Donald B. Karner ETA-AC006 Revision 2 2 ©1997 Electric Transportation Applications All Rights Reserved TABLE OF CONTENTS 1.0 Objectives 3 2.0 Purpose 3 3.0 Documentation 3 4.0 Initial Conditions and Prerequisites 4 5.0 Verification Requirements 5 6.0 Glossary 11 7.0 References 12 Appendices Appendix A - Manufacturer's Proposal Review Check List 13 Appendix B - Vehicle Receipt Check List 18 ETA-AC006 Revision 2 3

99

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

100

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

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

Catalog of DC Appliances and Power Systems  

E-Print Network (OSTI)

en.wikipedia.org/wiki/Variable-frequency_drive. Garbesi,are generally powered by variable frequency drives.The typical variable frequency drive first rectifies the AC

Garbesi, Karina

2012-01-01T23:59:59.000Z

102

Frequency–dependent numerical dynamics in mosquitofish  

Science Journals Connector (OSTI)

...can invade, but not drive the others extinct...equilibrium of genotype frequencies and total numbers...replication in the low-frequency treatment because the...treatment to be more variable. Mesocosms were established...from throw-trap data Frequency-dependent numerical...

2002-01-01T23:59:59.000Z

103

Frequency dependent magnetoconductivity and conductivity study in Ni-dispersed silica nano-composite produced by sol-gel technique  

Science Journals Connector (OSTI)

The low frequency (20 Hz to 1 MHz) ac conductivity and magnetoconductivity behaviour of ceramic nanocomposite (Ni-SiO2) at low temperature down to 77 K are reported. The frequency dependent conductivity followed ...

A. Sarkar; P. Ghosh; S. K. Chattopadhyay; A. K. Meikap…

104

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

105

Gene Frequency  

NLE Websites -- All DOE Office Websites (Extended Search)

Gene Frequency Gene Frequency Name: donna Location: N/A Country: N/A Date: N/A Question: If six fingers is a dominant human trait why do we have only five? Replies: This is simple. There are just not many genes in the human population for six fingers. Steve Sample Look in any high school biology book for what is known as Hardy-Weinberg equilibrium. These two scientists (separately) said that gene frequencies do not change much unless something in the environment selects them over other genes. In other words, unless 6 fingers somehow becomes an advantage, and five-fingered people have less of an advantage, the frequency of six fingered people in the population will not necessarily increase. This is the same reason that recessive traits don't disappear from the population. Also, six fingers is not considered attractive and they may not get as many mates. Also, more people are born with six fingers than you might imagine but just have them amputated shortly after birth.

106

Study of AC/RF properties of SRF ingot niobium  

SciTech Connect

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

107

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@et.aau.dk Abstract--In near future, with high penetration of Wind Energy (WE) in power system, the burden of Load

Silva, Filipe Faria Da

108

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

109

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

NLE Websites -- All DOE Office Websites (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...

110

Alternative Fuels at AC Transit  

NLE Websites -- All DOE Office Websites (Extended Search)

Alternative Fuels at AC Transit Alternative Fuels at AC Transit Speaker(s): Jaimie Levin Date: November 1, 2011 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Eve Edelson Mr. Levin will discuss AC Transit's range of environmental technology initiatives, including: zero emission fuel cell transit buses; state-of-the-art, high-capacity, hydrogen fueling stations; solar energy systems; and stationary solid oxide fuel cell power generators. AC Transit has the largest fleet of fuel cell buses in the United States, featuring fuel cell systems with more than 10,000 hours of continuous operation without any failures or power degradation. Their fuel cell fleet has logged more than 400,000 miles of service and carried in excess of one million passengers. Come hear what AC Transit has learned, where they're headed,

111

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

112

Variables Affecting Economic Development of Wind Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Variables Affecting Economic Variables Affecting Economic Development of Wind Energy E. Lantz and S. Tegen National Renewable Energy Laboratory Presented at WINDPOWER 2008 Houston, Texas June 1-4, 2008 Conference Paper NREL/CP-500-43506 July 2008 NREL is operated by Midwest Research Institute ● Battelle Contract No. DE-AC36-99-GO10337 NOTICE The submitted manuscript has been offered by an employee of the Midwest Research Institute (MRI), a contractor of the US Government under Contract No. DE-AC36-99GO10337. Accordingly, the US Government and MRI retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes. This report was prepared as an account of work sponsored by an agency of the United States government.

113

Chapter Seven - Variable speed drives  

Science Journals Connector (OSTI)

Publisher Summary The electromechanical controllers are a kind of variable speed drives (VSDs) that are obsolete but are still in use because when a motor and a drive is combined, they become a power drive system (PDS). There are two ways of varying the speed of an induction motor, either by varying the motor slip or by varying the supply frequency. The preferred practice for electrical speed variation is to change the supply frequency with a variable frequency drive (VFD). Many other designs also have been developed. However, except the specialized applications, few are still in operation. A number of motor and drive manufacturers are now producing the integrated motor/VFD units. These units consist of a motor and a specially designed VFD, produced as a single package, with the VFD unit mounted variously on the top, side, or end of the motor.

Europump; Hydraulic Institute

2005-01-01T23:59:59.000Z

114

Performance Variability  

NLE Websites -- All DOE Office Websites (Extended Search)

Variability Variability of Highly Parallel Architectures William T.C. Kramer 1 and Clint Ryan 2 1 Department of Computing Sciences, University of California at Berkeley and the National Energy Research Scientific Computing Center, Lawrence Berkeley National Laboratory 2 Department of Computing Sciences, University of California at Berkeley Abstract. The design and evaluation of high performance computers has concentrated on increasing computational speed for applications. This performance is often measured on a well configured dedicated sys- tem to show the best case. In the real environment, resources are not always dedicated to a single task, and systems run tasks that may influ- ence each other, so run times vary, sometimes to an unreasonably large extent. This paper explores the amount of variation seen across four large distributed memory systems in a systematic manner. It then

115

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

116

Metal slits and liquid crystals at microwave frequencies  

Science Journals Connector (OSTI)

...the possible use of dual frequency materials to allow drive-on as well as drive-off. Unfortunately such dual-frequency materials have reduced...T Nomoto2002Microwave variable delay line using dual-frequency switching-mode liquid...

2006-01-01T23:59:59.000Z

117

ACS calibration pipeline testing: error propagation  

E-Print Network (OSTI)

1 ACS calibration pipeline testing: error propagation Doug Van Orsow, Max Mutchler, Warren Hack files (see ISRs 99-03 "CALACS Operation and Implementation" by Hack and 99-04 "ACS calibra- tion

Sirianni, Marco

118

ACS SYMPOSIUM SERIES 966 Rational Environmental  

E-Print Network (OSTI)

ACS SYMPOSIUM SERIES 966 Rational Environmental Management of Agrochemicals Risk Assessment-Bayo, Editor Chiha University Sponsored by the ACS Division of Agrochemicals American Chemical Society of agrochemicals : risk assessment, monitoring, and remedial action / Ivan R. Kennedy, editor. ..[et al

Hammock, Bruce D.

119

ACS_RRA_2001.PDF  

NLE Websites -- All DOE Office Websites (Extended Search)

Qualitative and Semi-quantitative Qualitative and Semi-quantitative Analysis Of Semi-volatile Organics from Ambient Air Fine-particulate Matter, PM 2.5 Richard Anderson, Don Martello, Brian R. Strazisar and Curt M. White richard.anderson@netl.doe.gov ACS-222 / RRA' / ST-10 / 8-28-2001 Different Missions * EPA - Protect the public health * DOE - Assist the private sector in supplying clean, abundant, and affordable energy ACS-222 / RRA' / ST-10 / 8-28-2001 PM 2.5 Regulatory Process * 1997 National Ambient Air Quality Standards (NAAQS) for PM 2.5 based on "health effects" - Mean annual concentration < 15 µg/m 3 - Maximum concentration < 65µg/ m 3 ACS-222 / RRA' / ST-10 / 8-28-2001 Why Is DOE Concerned About PM 2.5 ? * Coal-based power systems contribute to PM 2.5 - Primary particles * Ultra-fine fly-ash (Spherical Alumino-silicates,SAS), carbon soot

120

High frequency rectenna  

DOE Patents (OSTI)

The invention provides an inexpensive array of rectifying antennas which employ field emission diodes for rectifying electromagnetic waves of microwave frequencies and higher frequencies.

Logan, B. Grant (Danville, CA); Orvis, William J. (Livermore, CA)

1991-01-01T23:59:59.000Z

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

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

E-Print Network (OSTI)

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

122

A Comparative Study on AC Conductivity and Dielectric Behavior of Multiwalled Carbon Nanotubes and Polyaniline Coated Multiwalled Carbon Nanotubes Filled High Density Polyethylene-Carbon Black Nanocomposites  

SciTech Connect

This paper presents an experimental investigation on AC conductivity and dielectric behavior of carbon black reinforced high density polyethylene (HDPE-CB) and HDPE-CB filled with multiwalled carbon nanotubes (MWNTs-CB-HDPE) and Polyaniline (PAni) coated MWNTs-CB-HDPE nanocomposites. The electrical properties such as dielectric constant ({epsilon}'), dissipation factor (tan {delta}) and AC conductivity ({sigma}{sub ac}) of nanocomposites have been measured with reference to the weight fraction (0.5 and 1 wt% MWNTs), frequency (75 KHz-30 MHz), temperature (25-90 deg. C) and sea water ageing. The experimental results showed that the increased AC conductivity and dielectric constant of the nanocomposites were influenced by PAni coated MWNTs in HDPE-CB nanocomposites. The value of dielectric constant and tan {delta} decreased with increasing frequency. Further more, above 5 MHz the AC conductivity increases drastically whereas significant effect on tan {delta} was observed in less than 1 MHz.

Dinesh, P. [Department of Electronics and Communication, Nagarjuna College of Engineering and Technology, Bangalore-562 110 Karnataka (India); Department of Electronics and Communication, Sri Jayachamarajendra College of Engineering, Mysore-570 006, Karnataka (India); Renukappa, N. M. [Department of Electronics and Communication, Sri Jayachamarajendra College of Engineering, Mysore-570 006, Karnataka (India); Siddaramaiah [Department of Polymer Science and Technology, Sri Jayachamarajendra College of Engineering, Mysore-570 006, Karnataka (India); Lee, J. H. [School of Advanced Materials Engineering, Chonbuk National University, Jeonbuk 561 756 (Korea, Republic of); Jeevananda, T. [R and D Centre, Department of Chemistry, R.N.S. Institute of Technology, Bangalore-560 061, Karnataka (India)

2010-10-04T23:59:59.000Z

123

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

124

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.

125

Self-Excited ac High Voltage Generation Using Water Droplets  

Science Journals Connector (OSTI)

By letting water drops fall through rings into cans high voltage can be spontaneously generated with no external electrical excitation. Previous work concerning this type of electric influence machine for dc and three-phase ac high voltage generation is extended to include multiphase multifrequency operation by considering N streams and N cans. A distributed equivalent circuit representation is used to calculate the natural frequencies of the system where it is found that many overstable modes are present. Experimental observations with up to five cans are presented. This device can serve as a model for phenomena concerned with atmospheric electricity.

Markus Zahn

1973-01-01T23:59:59.000Z

126

Chapter 18: Variable Frequency Drive Evaluation Protocol. The...  

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

by Pat Corkery, NREL 16560, photo by Dennis Schroeder, NREL 17613, photo by Dean Armstrong, NREL 17436, photo by Pat Corkery, NREL 17721. NREL prints on paper that contains...

127

Conserving Energy in Blast Freezers Using Variable Frequency Drives  

E-Print Network (OSTI)

; Freezing Time vs Velocity 6 7 8 9 10 11 12 13 14 0 500 1000 1500 Air Velocity (fpm) Freezing Time (hr) Freezing Time vs Carton Thickness 6 7 8 9 10 11 12 13 14 2 2.5 3 3.5 4 4.5 Carton Thickness (in.) Freezing Time (hr...: - Low-stage: 14? Hg vacuum (-50°F); - Intermediate stage controlled to 14 psig ( -2.5°F) and fluctuating some with load (increasing with higher load); - High-stage operates between 157 and 167 psig (87° and 91°F). An automatic monitoring...

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

2004-01-01T23:59:59.000Z

128

AC electrokinetic manipulation of selenium nanoparticles for potential nanosensor applications  

SciTech Connect

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

129

Eastern Frequency Response Study  

SciTech Connect

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

130

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

131

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

132

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

133

Design of AC substation grounding system.  

E-Print Network (OSTI)

??The purpose for this paper is to understand the basic foundation used to safely design a substation grounding system for AC systems. The following criteria… (more)

Meas, Ra

2014-01-01T23:59:59.000Z

134

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

135

Frequency selective infrared sensors  

SciTech Connect

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

136

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.

137

Digital Control of Resonant Converters: Enhancing Frequency Resolution by Dithering  

E-Print Network (OSTI)

-resolution frequency drive when the quality factor of the network is high or to avoid limit cycle oscillations resolution enhancer for resonant network drive. I. INTRODUCTION In a variety of applications, variable ballasts piezoelectric devices) [1-3]. In such cases, the frequency resolution of the drive is crucial

138

Effect of Ion Correlations on High?Frequency Plasma Conductivity  

Science Journals Connector (OSTI)

In an earlier work the ac conductivity of a plasma was investigated by means of an elementary model. The validity of this model has been borne out by a rigorous treatment of plasma at thermal equilibrium. The elementary model is now extended to include the effects of ion correlations for arbitrary fixed ion distributions. For thermal equilibrium correlations it is found that the ion shielding reduces the maximum effective impact parameter by the factor (1 + Z)½ (i.e. both ions and electrons contribute to the shielding) for frequencies low compared to the plasma frequency ?p. For frequencies high compared to ?p the previous results obtain. The resistance due to the excitation of longitudinal waves at frequencies just in excess of ?p is reduced by the factor (1 + Z)?1. However if large?amplitude (nonthermal) ion fluctuations are present the longitudinal wave contribution to the resistance may be greatly enhanced.

John Dawson; Carl Oberman

1963-01-01T23:59:59.000Z

139

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...

140

AVTA: Blink AC Level 2 Charging System Testing Results | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

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.


141

AVTA: Schneider AC Level 2 Charging System Testing Results |...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

142

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

143

AVTA: SPX AC Level 2 Charging System Testing Results | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

144

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

145

E-Print Network 3.0 - acute vocal variability Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

phonation Patrick Mergella) Summary: upon variation in some other variable, such as frequency or the angle of the vocal membranes... Modeling the role of nonhuman vocal membranes...

146

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

147

Pitch-Controlled Variable-Speed Wind Turbine Generation  

NLE Websites -- All DOE Office Websites (Extended Search)

Pitch-Controlled Variable-Speed Pitch-Controlled Variable-Speed Wind Turbine Generation February 2000 * NREL/CP-500-27143 E. Muljadi and C.P. Butterfield Presented at the 1999 IEEE Industry Applications Society Annual Meeting Phoenix, Arizona October 3-7, 1999 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute * * * * Battelle * * * * Bechtel Contract No. DE-AC36-99-GO10337 NOTICE The submitted manuscript has been offered by an employee of the Midwest Research Institute (MRI), a contractor of the US Government under Contract No. DE-AC36-99GO10337. Accordingly, the US Government and MRI retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes.

148

Frequency Combs for Astronomy  

Science Journals Connector (OSTI)

For the first time a mode filtered frequency comb has been used to calibrate an astronomical spectrometer online. Solar and calibration spectra have been recorded simultaneously.

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

149

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

150

Standard Frequency Broadcasts  

Science Journals Connector (OSTI)

... Mc./sec., at least three of which are available at any time; standard audio frequencies of 440 and 4,000 c./sec. broadcast on these carriers; and ... second of every minute the pulse is omitted. The 1-min. interval in the audio-frequency transmission is used to give the station announcement, either in Morse or (at ...

1944-09-02T23:59:59.000Z

151

Frequency-doubling in femtosecond laser inscribed periodically-poled potassium titanyl  

E-Print Network (OSTI)

, Sweden *Corresponding author: d.t.reid@hw.ac.uk Abstract: Frequency doubling has been achieved and M. Pierrou, " High power blue light generation in segmented KTiOPO4 waveguides," 8th European waveguides written with a femtosecond laser for flexible interconnection in a planar light-wave circuit," Opt

152

ACS Meeting and Chemical Exposition Draw Large Attendance  

Science Journals Connector (OSTI)

ACS Meeting and Chemical Exposition Draw Large Attendance ... Copyright © 1958 American Chemical Society ...

1958-06-01T23:59:59.000Z

153

Safe-commutation principle for direct single-phase AC-AC converters for use in audio power  

E-Print Network (OSTI)

Safe-commutation principle for direct single-phase AC-AC converters for use in audio power-stage AC-AC audio power amplifiers. As compared with the bridge commutation with load current or source is certainly the audio power amplification. Switching-mode Class D audio power amplifiers are becoming

154

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

155

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

156

The dependence of AC loss characteristics on the spacing between strands in YBCO Roebel  

Science Journals Connector (OSTI)

Transport AC loss in a short length of 9/2 YBCO Roebel cable, (i.e. with 9 ? 2 mm width strands), with 0.25 mm spacers between the strands is measured. The frequency varies from 59 to 354 Hz. The result is compared with the loss for a cable without spacers between the strands. Transport AC loss is decreased by the presence of the spacers. The AC loss reduction due to the extra spacing is more significant when the amplitude of the cable current is small compared to the cable Ic. The losses in the cable with spacers normalized by the square of the cable currents plotted against It/Ic approximately agree with those in a cable without spacers. Electromagnetic modelling was carried out for 9/2 and 8/2 cables, modelled as parallel stacks, to assist in understanding the above experimental results. The 8/2 configuration allows the greater use of symmetry to speed computations. Reasonable agreement between the numerical results and the measured results was obtained. This supports suggestions made in previous publications that the transport AC loss in a Roebel cable is roughly equivalent to the loss in two parallel stacks carrying the same current in each tape. The electromagnetic analysis in the 8/2 stacks shows the flux lines are more perpendicular to the strand face when the vertical space between strands is smaller, and this leads to a larger induced electrical field and larger AC loss. At small current amplitudes, the modelling shows the spacing has a strong effect on the AC loss in the surfaced part of the strands.

Zhenan Jiang; K P Thakur; Mike Staines; R A Badcock; N J Long; R G Buckley; A D Caplin; Naoyuki Amemiya

2011-01-01T23:59:59.000Z

157

ACS calibration pipeline testing: basic image reduction  

E-Print Network (OSTI)

Hack, Colin Cox Space Telescope Science Institute 28 May 1999 ABSTRACT This report describes the basic. For a detailed description of CALACS, see ACS Instrument Science Report 99-03 by Hack. This report describes

Sirianni, Marco

158

ACS workshop in India proposes eight projects  

Science Journals Connector (OSTI)

ACS workshop in India proposes eight projects ... • Investigate the solid-state chemistry of processes and materials needed for using solar energy to split water and for transporting and storing the resulting hydrogen for use as a fuel. ...

1980-03-31T23:59:59.000Z

159

IEEE POWER ELECTRONICS LETTERS 1 A Constant-Frequency Method for Improving  

E-Print Network (OSTI)

these are resonant gate drive [3]­[5], pulse frequency modulation (PFM) [6], and a hybrid Manuscript received, in the case of the variable-frequency methods, their potential for generating undesired noise at subharmonicsIEEE POWER ELECTRONICS LETTERS 1 A Constant-Frequency Method for Improving Light-Load Efficiency

Lee, Thomas H.

160

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

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

UEA Water Security Research Centre Climate Change and Variability Adaptation and Vulnerability  

E-Print Network (OSTI)

UEA Water Security Research Centre Climate Change and Variability · Adaptation and Vulnerability · Transboundary Cooperation ­ Conflict · Irrigation Performance and Policy · River Basin Management · Water Allocation · Hydropolitics www.uea.ac.uk/watersecurity #12;The UEA Water Security Research Centre applies

Everest, Graham R

162

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

163

r XXXX American Chemical Society A dx.doi.org/10.1021/ac201626b |Anal. Chem. XXXX, XXX, 000000 pubs.acs.org/ac  

E-Print Network (OSTI)

proposed as a platform for miniaturized chemical sen- sor systems. However, only a few systems achieve massr XXXX American Chemical Society A dx.doi.org/10.1021/ac201626b |Anal. Chem. XXXX, XXX, 000­000 ARTICLE pubs.acs.org/ac Chemical Vapor Detection Using a Capacitive Micromachined Ultrasonic Transducer

Khuri-Yakub, Butrus T. "Pierre"

164

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

165

debussy@cs.yonsei.ac.kr, iklee@yonsei.ac.kr Affective Icons for Music Exploring  

E-Print Network (OSTI)

O debussy@cs.yonsei.ac.kr, iklee@yonsei.ac.kr Affective Icons for Music Exploring Min and colors of harmonograph curves. These curves can be used as icons for music retrieval, and we demonstrate. This approach is compatible with a standard icon-based file browser. . Introduction Since the appearance

Lee, In-Kwon

166

Transmission, S-matrix, and partial densities of states for ac transport through a resonant cavity with multileads  

Science Journals Connector (OSTI)

We investigate the principal properties of ac transport through a resonant cavity with multileads. In terms of Green’s function and the coupling strengths of the system, a set of general expressions for the partial densities of states (PDOS) can be derived in an unambiguous way. In particular we derive the PDOS with a reflection property. All the PDOS’s are in an explicit and compact form. Based upon these PDOS’s, the ac conductance can be calculated to a first-order frequency-dependent term. As an extension, we introduce the second-order nonlinear PDOS; then the ac conductance can be generalized to include the second-order contribution. As an example, we apply these formulas to evaluate the linear emittance and the second-order nonlinear emittance in a simplified structure. Some interesting results are obtained.

Xuean Zhao, Guo-jun Jin, Qi-nian Zhou, and You-quan Li

2002-07-25T23:59:59.000Z

167

Frequencies for Radio Astronomy  

Science Journals Connector (OSTI)

... must therefore be achieved through the combined action of three international scientific unions, IAU (astronomy), COSPAR (space) and URSI (radio), which jointly delegate members to an ... jointly delegate members to an Inter-Union Commission for the Allocation of Frequencies for Radio Astronomy and Space Science (IUCAF). This Commission discusses the scientific case for protecting various ...

F. G. SMITH

1970-10-31T23:59:59.000Z

168

Variability in Measured Space Temperatures in 60 Homes  

NLE Websites -- All DOE Office Websites (Extended Search)

Variability in Measured Space Variability in Measured Space Temperatures in 60 Homes David Roberts National Renewable Energy Laboratory Kerylyn Lay EnerNOC (formerly of the National Renewable Energy Laboratory) Technical Report NREL/TP-5500-58059 March 2013 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 15013 Denver West Parkway Golden, Colorado 80401 303-275-3000 * www.nrel.gov Contract No. DE-AC36-08GO28308 Variability in Measured Space Temperatures in 60 Homes David Roberts National Renewable Energy Laboratory Kerylyn Lay EnerNOC (formerly of the National Renewable Energy Laboratory)

169

A 1.6-to-3.2/4.8 GHz Dual-Modulus Injection-Locked Frequency Multiplier in 0.18  

E-Print Network (OSTI)

: hwu@ece.rochester.edu Abstract-- This paper proposes a variable-modulus injection- locked frequency. Variable-modulus frequency multiplier can be a low-cost solution for a multi-band system to switch, as the frequency multiplier needs to drive its load at a certain power level. Undesired har- monics at the output

Wu, Hui

170

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

171

7AC Technologies, Inc. | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7AC 7AC Technologies, Inc. America's Next Top Energy Innovator Challenge 498 likes 7AC Technologies, Inc. National Renewable Energy Laboratory Air conditioning is a very large contributor to U.S. and world energy consumption. Heating and cooling costs for commercial and industrial buildings exceed 25 percent of U.S. primary energy consumption (cooling alone accounts for 4.5 Quads out of 40 Quads) and typically accounts for almost half of a building's operating costs. Air conditioning is also a significant cause of grid instability with cycling compressor motors turning on and off, and causing load issues on hot summer days. Conventional air conditioners improve efficiency only marginally every year and retrofitting older rooftop units does not result in significant energy

172

7AC Technologies, Inc. | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7AC 7AC Technologies, Inc. America's Next Top Energy Innovator Challenge 498 likes 7AC Technologies, Inc. National Renewable Energy Laboratory Air conditioning is a very large contributor to U.S. and world energy consumption. Heating and cooling costs for commercial and industrial buildings exceed 25 percent of U.S. primary energy consumption (cooling alone accounts for 4.5 Quads out of 40 Quads) and typically accounts for almost half of a building's operating costs. Air conditioning is also a significant cause of grid instability with cycling compressor motors turning on and off, and causing load issues on hot summer days. Conventional air conditioners improve efficiency only marginally every year and retrofitting older rooftop units does not result in significant energy

173

Princeton Plasma Physics Lab - AC power  

NLE Websites -- All DOE Office Websites (Extended Search)

ac-power The electricity that runs the ac-power The electricity that runs the Laboratory's experiments and facilities. "AC" stands for the alternating current that comes from large power stations. The term compares with "DC," for "direct current," which comes from sources like batteries. en Offshore Wind and Vehicle to Grid Power http://www.pppl.gov/events/offshore-wind-and-vehicle-grid-power

Professor Willett Kempton, of the University of Delaware, presents "Offshore Wind and Vehicle to Grid Power" as part of the Andlinger Center's 2013-2014 Highlight Seminar Series.

174

7AC Technologies, Inc. | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7AC 7AC Technologies, Inc. America's Next Top Energy Innovator Challenge 498 likes 7AC Technologies, Inc. National Renewable Energy Laboratory Air conditioning is a very large contributor to U.S. and world energy consumption. Heating and cooling costs for commercial and industrial buildings exceed 25 percent of U.S. primary energy consumption (cooling alone accounts for 4.5 Quads out of 40 Quads) and typically accounts for almost half of a building's operating costs. Air conditioning is also a significant cause of grid instability with cycling compressor motors turning on and off, and causing load issues on hot summer days. Conventional air conditioners improve efficiency only marginally every year and retrofitting older rooftop units does not result in significant energy

175

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

176

AC H I E V I NG  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

AC AC H I E V I NG The Department's strategic plan flow is highlighted in the cascade below beginning with the mission statement which flows to the strategic themes. The strategic themes connect to the broader strategic goals and are linked to the annual performance goals in the performance budget through the multi-year program plans. The multi-year program plans allow DOE to strategize over a five-year period how each program will implement the strategic goals of the Department. Annual performance goals and assessment of performance against prior-year

177

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

178

r XXXX American Chemical Society A dx.doi.org/10.1021/nl201505c |Nano Lett. XXXX, XXX, 000000 pubs.acs.org/NanoLett  

E-Print Network (OSTI)

with variable frequency (mostly low frequencies) and magnitude, such as airflow, noises, human activity, which possible to drive the devices by scavenging energy from the sources in the environment such as gentle frequen- cies. A rational design is required to tolerate the variable environment. The nanogenerator (NG

Wang, Zhong L.

179

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

180

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.

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

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

182

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

183

www.jubileecentre.ac.uk JAMES ARTHUR  

E-Print Network (OSTI)

www.jubileecentre.ac.uk JAMES ARTHUR KRISTJÁN KRISTJÁNSSON HYWEL THOMAS MICHAEL HOLDSWORTH LUCA BADINI CONFALONIERI TIAN QIU FOREWORD BY PROFESSOR ADRIAN EVANS VIRTUOUS CHARACTERFOR THE PRACTICE OF LAW by Professor James Arthur. Based at the University of Birmingham, it has a dedicated team of 30 academics from

Birmingham, University of

184

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

185

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

186

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

187

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

188

Modeling the High-Frequency Component of Arctic Sea Ice Drift and Deformation  

Science Journals Connector (OSTI)

Buoy observations of sea ice drift show that sea ice motion and deformation contain substantial high-frequency variability at subdaily timescales. However, numerical simulations of the sea ice dynamics normally do not include processes on such ...

Petra Heil; William D. Hibler III

2002-11-01T23:59:59.000Z

189

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

190

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

191

Frequency Scalable Non-Linear Waveform Generator for Mixed-Simal Power-Factor-Correction IC Controller'  

E-Print Network (OSTI)

operates with a fixed switching frequency fs and variable duty ratio R, and can be analyzed using standard of a switching period, a fixed-frequency clock pulse sets the switch drive high. A signal proportionalFrequency Scalable Non-Linear Waveform Generator for Mixed-Simal Power-Factor-Correction IC

192

The XRCC1 399Gln Polymorphism and the Frequency of p53 Mutations in Taiwanese Oral Squamous Cell Carcinomas  

Science Journals Connector (OSTI)

...association with the frequency of p53 mutation...genetic lesions that drive human carcinogenesis...significantly increased the frequency of p53 mutations...399 genotype and the frequency of p53 gene mutation Variable Gln/Gln Gln/Arg...

Ling-Ling Hsieh; Huei-Tzu Chien; I-How Chen; Chun-Ta Liao; Hung-Ming Wang; Shih-Ming Jung; Pei-Feng Wang; Joseph Tung-Chieh Chang; Min-Chi Chen; and Ann-Joy Cheng

2003-05-01T23:59:59.000Z

193

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

194

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.

195

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"

196

AC Solar Inc | Open Energy Information  

Open Energy Info (EERE)

Logo: AC Solar Inc Name AC Solar Inc Address P.O. Box 128 Place Florence, Colorado Zip 81226 Sector Solar Product Solar and wind sales for residential Website http://www.acsolar.com/ Coordinates 38.381551°, -105.112265° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.381551,"lon":-105.112265,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

197

Direct amplitude detuning measurement with ac dipole  

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

198

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

199

Variable depth core sampler  

DOE Patents (OSTI)

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

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

1996-01-01T23:59:59.000Z

200

Variable laser attenuator  

DOE Patents (OSTI)

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

Foltyn, S.R.

1987-05-29T23:59:59.000Z

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.


201

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

202

Abstract--The induction motor is well known as the workhorse of industry. The development of variable speed  

E-Print Network (OSTI)

of variable speed induction motor drives has a long history of more than four decades. Today's sophisticated--Induction motor control I. INTRODUCTION EFORE the invention of variable frequency voltage and current source inverters the induction motor was never thought as continuously variable speed drive. Only some adaptations

Paderborn, Universität

203

Sensors and Actuators A 132 (2006) 139146 MEMS based digital variable capacitors with a high-k dielectric insulator  

E-Print Network (OSTI)

; Digital variable capacitor; High-k dielectric; Charge injection 1. Introduction Radio-frequency (RF]. The other one is the area tuning variable capacitor typically using a comb-drive structure which is normallySensors and Actuators A 132 (2006) 139­146 MEMS based digital variable capacitors with a high

Fleck, Norman A.

204

NONLINEAR MAGNETOHYDRODYNAMICS OF AC HELICITY INJECTION  

NLE Websites -- All DOE Office Websites (Extended Search)

parameter: the driving fre- quency . The lower the frequency, the greater the classical penetration and the higher the helicity injection rate. On the other hand, the field...

205

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

206

Backstepping control of DFIG generators for wide-range variable-speed wind turbines  

Science Journals Connector (OSTI)

In this paper, we have presented a general study of self excited induction generator used in isolated renewable energy conversion source. Tthe behaviour of generated voltage under variable load, rotor speed and excitation capacitance is presented. Also, we have proposed a robust controller suitable in order to control the terminal DC voltage under different speed and AC load conditions for supplied an isolated DC load. The experimental characteristic curve of the generator and simulation result of proposed control scheme are presented.

Badre Bossoufi; Mohammed Karim; Ahmed Lagrioui; Mohammed Taoussi; Mohamed Larbi ElHafyani

2014-01-01T23:59:59.000Z

207

Audio-Frequency Power Measurements  

Science Journals Connector (OSTI)

... " prepared by the National Physical Laboratory, Teddington, is a brief pamphlet dealing with "Audio-Frequency Power Measurements" (pp. 16. London: H.M.S.O., 1954; ...

1955-09-10T23:59:59.000Z

208

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

209

The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS  

Science Journals Connector (OSTI)

Using the International Best Track Archive for Climate Stewardship (IBTrACS), the climatology of tropical cyclones is compared between two global best track datasets: 1) the World Meteorological Organization (WMO) subset of IBTrACS (IBTrACS-WMO) ...

Carl J. Schreck III; Kenneth R. Knapp; James P. Kossin

2014-10-01T23:59:59.000Z

210

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

NLE Websites -- All DOE Office Websites (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...

211

E-Print Network 3.0 - ac systems Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary: -6261 E-mail: kuni@mind.c.u-tokyo.ac.jp http:mind.c.u-tokyo.ac.jpindex-j.html 1890 20 Systems... 12;1 4647 4025 http:bio.c.u-tokyo.ac... ......

212

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

NLE Websites -- All DOE Office Websites (Extended Search)

Summary: -6261 E-mail: kuni@mind.c.u-tokyo.ac.jp http:mind.c.u-tokyo.ac.jpindex-j.html 1890 20 Systems... 12;1 4647 4025 http:bio.c.u-tokyo.ac... ......

213

A study on current characteristics of induction motor while operating at its base frequency in textile industry  

Science Journals Connector (OSTI)

Abstract In the increasing amounts of three-phase squirrel-cage induction motors over the years are fed by variable-speed drives in majority of the industries. This paper deals about the current and power characteristics of induction motor while it operating at its base frequency with variable speed drive. Various studies have been conducted in textile industry to prove the above phenomena. When the motor runs at its base frequency through VFD (variable-frequency drive), considerable energy saving is possible. In this study, around 3.6 units saved for one operating cycle of Ringframe machine in textile industry.

Y. Dhayaneswaran; L. Ashok Kumar

2014-01-01T23:59:59.000Z

214

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

215

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

216

Wind- versus Eddy-Forced Regional Sea Level Trends and Variability in the North Pacific Ocean  

Science Journals Connector (OSTI)

Regional sea level trend and variability in the Pacific Ocean have often been considered to be induced by low-frequency surface wind changes. In this study, we demonstrate that significant sea level trend and variability can also be generated by ...

Bo Qiu; Shuiming Chen; Lixin Wu; Shinichiro Kida

217

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

218

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

NLE Websites -- All DOE Office Websites (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...

219

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

Energy.gov (U.S. Department of Energy (DOE)) 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...

220

56TH ACS NORTHWEST REGIONAL MEETING  

Science Journals Connector (OSTI)

56TH ACS NORTHWEST REGIONAL MEETING ... Several plenary sessions and interdisciplinary public lectures will address this theme, including "Technology for the 21st Century," presented by Lura J. Powell, director, Pacific Northwest National Laboratory; "DNA and Molecular Recognition," presented by Jacqueline Barton, California Institute of Technology; "Bioengineering Tissues," presented by Buddy Ratner, University of Washington; "History and Chemistry of Plutonium Extraction at Hanford," presented by Earl Wheelwright, Pacific Northwest National Laboratory; "Life in the Universe," presented by Donald Brownlee, University ofWashington; "Climate Change: How Will It Affect the Pacific Northwest?" presented by Jae Edmonds, Pacific Northwest National Laboratory; and "The Future of Science Education," presented by ... ...

2001-05-14T23:59:59.000Z

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
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221

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

222

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

223

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

E-Print Network (OSTI)

to prepare? Alison Proudlove Thursday, June 07, 2012 1 #12;www.mmu.ac.uk/careers What will we cover researched the organisation #12;www.mmu.ac.uk/careers Use your time wisely · If there are large queues , have

224

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

225

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

226

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

227

Sensible and Latent Cooling Load Control Using Centrally-Ducted, Variable-Capacity Space Conditioning Systems in Low Sensible Load Environments  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Sensible and Latent Cooling Load Control Using Centrally-Ducted, Variable-Capacity Space Conditioning Systems in Low Sensible Load Environments James Cummings BA-PIRC; Florida Solar Energy Center Presented at BA Summer Meeting, July 26, 2012 The gist of my message * Fixed capacity AC systems generally provide good RH control in typical residences. * In low-load homes, they may be less effective in achieving good RH control. * On the other hand, variable capacity AC systems have several characteristics which can provide improved RH control in homes. - Both Nordyne and Carrier have variable capacity units, varying from about 40% to 100% of nominal full capacity. - What is variable capacity? -- condenser fan, compressor speed, and AHU fan speed. The gist, continued

228

Microwave and Radio Frequency Workshop  

Energy.gov (U.S. Department of Energy (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 ...

229

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

230

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.

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

1982-01-01T23:59:59.000Z

231

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

232

Frequencies of Tetramer+ T Cells Specific for the Wild-Type Sequence p53264–272 Peptide in the Circulation of Patients with Head and Neck Cancer  

Science Journals Connector (OSTI)

...loglinear models to the frequencies of each variable in the 3 2 2 contingency...determined that the frequency of p53264-272-specific...of CTL, which might drive the selection of epitope-loss...mutations and a low frequency of wt p53-specific...

Thomas K. Hoffmann; Albert D. Donnenberg; Sydney D. Finkelstein; Vera S. Donnenberg; Ulrike Friebe-Hoffmann; Eugene N. Myers; Ettore Appella; Albert B. DeLeo; and Theresa L. Whiteside

2002-06-15T23:59:59.000Z

233

High frequency of K-ras codon 12 mutations in bronchoalveolar lavage fluid of patients at high risk for second primary lung cancer.  

Science Journals Connector (OSTI)

...lung cancer. | A high frequency of K-ras mutations...Cancer Research 479 High Frequency of K-ras Codon 12...ABSTRACT A high frequency of K-ras mutations...9610 Medical Center Drive, Rockville, MD 20850...specimens. Only a small, variable percent-age of bronchial...

F M Scott; R Modali; T A Lehman; M Seddon; K Kelly; E C Dempsey; V Wilson; M S Tockman; and J L Mulshine

1997-03-01T23:59:59.000Z

234

Photonic Radio-Frequency Phase Detector based on Radio-Frequency to Intermediate-Frequency Phase Mapping  

Science Journals Connector (OSTI)

A photonic radio-frequency phase detector based on radio-frequency (RF) to intermediate-frequency mapping is demonstrated, and the theoretical principle of the design is explained.

Sun, Dongning; Dong, Yi; Wang, Siwei; Xia, Zongyang; Xie, Weilin; Shi, Hongxiao; Yi, Lilin; Hu, Weisheng

235

Monitoring variability of multivariate processes  

Science Journals Connector (OSTI)

The paper focuses on determining changes in process variability of multivariate processes. The problem is compounded by the fact that any of the elements in the variance-covariance matrix of variables could change, leading to a change in the process variability. While it may not be feasible to maintain individual control charts for each element of the variance-covariance matrix, some aggregate measure of the variability criteria could be monitored to initially determine if a change has occurred in the process variability. A couple of aggregate measures are proposed and the performance of these suggested measures is explored through a simulation procedure. Compared to the traditional method, which monitors the determinant of the variance-covariance matrix, these alternatives perform well. The performance measure used is the mean time to first detection of a change in the process variability.

Amitava Mitra; Mark Clark

2014-01-01T23:59:59.000Z

236

E-Print Network 3.0 - ac transmission lines Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

lines Search Powered by Explorit Topic List Advanced Search Sample search results for: ac transmission lines...

237

E-Print Network 3.0 - ac transmission line Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

line Search Powered by Explorit Topic List Advanced Search Sample search results for: ac transmission line...

238

Optimal design of AC filter circuits in HVDC converter stations  

SciTech Connect

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

239

Measurement and Modeling of Solar and PV Output Variability: Preprint  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Measurement and Modeling of Measurement and Modeling of Solar and PV Output Variability Preprint M. Sengupta To be presented at SOLAR 2011 Raleigh, North Carolina May 17-21, 2011 Conference Paper NREL/CP-5500-51105 April 2011 NOTICE The submitted manuscript has been offered by an employee of the Alliance for Sustainable Energy, LLC (Alliance), a contractor of the US Government under Contract No. DE-AC36-08GO28308. Accordingly, the US Government and Alliance retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes. This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty,

240

Demand Response and Variable Generation Integration Scoping Study  

NLE Websites -- All DOE Office Websites (Extended Search)

The Impact of City-level Permitting The Impact of City-level Permitting Processes on Residential PV Installation Prices and Development Times An Empirical Analysis of Solar Systems in California Cities Ryan Wiser and CG Dong Lawrence Berkeley National Laboratory April 2013 This analysis was funded by the Solar Energy Technologies Office, Office of Energy Efficiency and Renewable Energy of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 Energy Analysis Department  Electricity Markets and Policy Group Presentation Overview * Questions and Objective * Literature Review * Data Sources and Processing * Variable Description and Summary * Regression Analysis Results * Interpretation and Predictions * Conclusions * Possible Future Extensions 2 Energy Analysis Department  Electricity Markets and Policy Group

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

Plateau structure in the Faraday rotation in the graphene quantum Hall system and the frequency-driven two-parameter scaling  

SciTech Connect

Flow diagram of (?{sub xx},?{sub xy}) in finite-frequency (?) regime is numerically studied for the graphene quantum Hall effect (QHE). In a small-? regime, the ac flow diagram exhibits a behavior qualitatively similar to the dc flow diagram, where the dynamical length scale acts as a cutoff in the ac region, and the flows are between ?{sub xy}?=?±(1/2)e{sup 2}/h reflecting the graphene QHE. The dynamical flow is compared with the temperature-driven flow.

Morimoto, Takahiro [Condensed Matter Theory Laboratory, Riken, Saitama, 351-0198 (Japan); Aoki, Hideo [Department of Physics, University of Tokyo, Hongo, Tokyo 113-0033 (Japan)

2013-12-04T23:59:59.000Z

242

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

243

Estimation of changes in energy consumption for heat supply due to interannual temperature variability in the south of the Ukraine  

Science Journals Connector (OSTI)

The influence of low-frequency variability of average over the heating season air temperature on population demands in heat supply is considered. Based on monthly mean temperature values for the period from 18...

A. Kh. Degterev; L. N. Degtereva

2008-11-01T23:59:59.000Z

244

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

245

High-frequency resonances in photorefractive crystals  

Science Journals Connector (OSTI)

Two-wave mixing in photorefractive materials is investigated for the case of applied dc electric fields and large detuning frequencies and for high-frequency alternating electric...

Grunnet-Jepsen, A; Aubrecht, I; Solymar, L

1995-01-01T23:59:59.000Z

246

Sum Frequency Generation for Surface Vibrational Spectroscopy...  

NLE Websites -- All DOE Office Websites (Extended Search)

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

247

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

SciTech Connect

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

248

Dynamic cancellation of ac Stark shift for pulsed EIT/Raman optical lattice clocks  

E-Print Network (OSTI)

We propose a combination of Electromagnetically Induced Transparency (EIT)/Raman and pulsed spectroscopy techniques to accurately cancel frequency shifts arising from EIT fields in forbidden optical lattice clock transitions of alkaline earth atoms. Time-separated laser pulses are designed to trap atoms in coherent superpositions while eliminating off-resonance ac Stark contributions at particular laser detunings from the intermediate excited state. The scheme achieves efficient population transfer up to 60% with potential inaccuracy $<$ $10^{-17}$. Cancellation of external light shifts determined by a density matrix approach is confirmed by a complex wave-function formalism, sufficient at the mHz accuracy, under low field strengths or short interaction times.

T. Zanon-Willette; A. D. Ludlow; S. Blatt; M. M. Boyd; E. Arimondo; * Jun Ye

2006-10-13T23:59:59.000Z

249

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

250

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

251

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

252

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

253

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

254

David M. Frohlich d.frohlich@surrey.ac.uk  

E-Print Network (OSTI)

19 David M. Frohlich d.frohlich@surrey.ac.uk Professor & Director, Digital World Research Centre in Community Content Creation FROHLICH, BHAT, JONES, LALMAS, FRANK, RACHOVIDES, TUCKER, RIGA Research Article

Lalmas, Mounia

255

Contract Number DE-AC27-10RV15051  

NLE Websites -- All DOE Office Websites (Extended Search)

Section H.26, Key Personnel, Pages i and H-32 Section J, Attachment 7, Performance Evaluation and Measurement Plan, Page J-127 222-S LAS&T Contract No. DE-AC27-10RV15051...

256

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

257

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

258

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

259

Accurate determination of the temperature and frequency dependent smectic C biaxial permittivity tensor  

Science Journals Connector (OSTI)

The temperature and frequency dependent smectic C bend (B 1 ) and splay (B 2 ) elastic constants and permittivities ? 1 ? 2 and ? 3 have been measured directly for a commercial smectic C liquid crystal mixture. This has been achieved using continuum modelling to fit the ac field dependence of the permittivity in the C2U chevron geometry. The fitting procedure also makes use of measured values for the homeotropic permittivity the layer tilt angle and smectic cone angle. This approach removes many of the assumptions which were inherent in previous measurements giving improved accuracy in the results.

Carl V. Brown; J. Cliff Jones

1999-01-01T23:59:59.000Z

260

Time Variability of the "Quiet" Sun Observed  

Science Journals Connector (OSTI)

The Transition Region and Coronal Explorer (TRACE) observed a "quiet-Sun" region on 1999 February 17 from 02:15 UT to 3:00 UT with full resolution (05 pixel size), high cadence (125 s), and deep exposures (65 and 46 s) in the 171 Å and 195 Å wavelengths. We start our investigation of the time variability of "quiet-Sun" images with a detailed analysis of instrumental and nonsolar effects, such as orbital temperature variations, filtering of particle radiation spikes, spacecraft pointing drift, and solar rotation tracking. We quantify the magnitude of various noise components (photon Poisson statistics, data digitization, data compression, and readout noise) and establish an upper limit for the data noise level, above which temporal variability can safely be attributed to solar origin. We develop a pattern recognition code that extracts spatiotemporal events with significant variability, yielding a total of 3131 events in 171 Å and 904 events in 195 Å. We classify all 904 events detected in 195 Å according to flarelike characteristics and establish a numerical flare criterion based on temporal, spatial, and dynamic cross-correlation coefficients between the two observed temperatures (0.9 and 1.4 MK). This numerical criterion matches the visual flare classification in 83% of the cases and can be used for automated flare search. Using this flare discrimination criterion we find that only 35% (and 25%) of the events detected in 171 (and 195) Å represent flarelike events. The discrimination of flare events leads to a frequency distribution of peak fluxes, N(?F) ? ?F-1.83±0.07 at 195 Å, which is significantly flatter than the distribution of all events. A sensitive discrimination criterion of flare events is therefore important for microflare statistics and for conclusions on their occurrence rate and efficiency for coronal heating.

Markus J. Aschwanden; Richard W. Nightingale; Ted D. Tarbell; C. J. Wolfson

2000-01-01T23:59:59.000Z

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

SVC implementation using neural networks for an AC electrical railway  

Science Journals Connector (OSTI)

This paper presents an on-line method for implementation of a static var compensator (SVC) in a real ac autotransformer (AT)-fed electrical railway for reactive power compensation using Neural Networks (NN). Genetic algorithm (GA) can be the off-line ... Keywords: AC electrical railways load flow, forward/backward sweep (FBS), genetic algorithm (GA), neural network (NN), reactive power compensation, static var compensator (SVC)

Saeid Veysi Raygani; Bijan Moaveni; Seyed Saeed Fazel; Amir Tahavorgar

2011-05-01T23:59:59.000Z

262

Development of an AC Module System: Final Technical Report  

SciTech Connect

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

263

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

264

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

265

Seasonal frequency of ciguatoxic barracuda in southwest Puerto Rico  

Science Journals Connector (OSTI)

Ciguatoxicity of barracuda (Sphyraena barracuda) head, viscera and flesh tissues has been determined in 219 specimens caught along the southwest coast of Puerto Rico from March 1985 through May 1987. Twenty-nine percent of these specimens were toxic. Monthly frequencies of ciguatoxic barracuda showed an apparent seasonal variability, with peak values (60–70% toxic fish) in the late winter-early spring (January–May) and fall (August–November). Minimal frequencies (0–10% toxic fish) were observed during June–July and December. The most frequently toxic tissues in poisonous animals were the viscera and head. Viscera tissue was the only toxic tissue found in 31% of the posionous fish assayed, and this tissue was poisonous in all toxic fish. In no case was a poisonous specimen found to have toxic flesh alone. Marked temporal variation in frequency of ciguatoxicity suggests that ciguatera toxins, at least in their active form, are not accumulated in barracuda tissues for extended periods of time. Variability in barracuda ciguatoxicity may reflect fluctuations in the toxicity of smaller reef fish prey, seasonal fluctuations in toxic benthic dinoflagellates and/or changes in the ability of the barracuda to detoxify ingested poisons or their precursors.

T.R. Tosteson; D.L. Ballantine; H.D. Durst

1988-01-01T23:59:59.000Z

266

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.

267

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

SciTech Connect

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

268

Installation considerations for IGBT AC drives  

SciTech Connect

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

269

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

270

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

271

On the Source of Midlatitude Low-Frequency Variability. Part II: Nonlinear Equilibration of Weather Regimes  

Science Journals Connector (OSTI)

We present a new statistical-dynamical approach to the concept of weather regimes, including the effect of tralisients, without any assumption other than scale separation. The method is applied to a quasi-geostrophic channel model without ...

Robert Vautard; Bernard Legras

1988-10-01T23:59:59.000Z

272

A spectrally accurate direct solution technique for frequency-domain scattering problems with variable media  

Science Journals Connector (OSTI)

This paper presents a direct solution technique for the scattering of time-harmonic waves from a bounded region of the plane in which the wavenumber varies smoothly in space. The method constructs the interior...

Adrianna Gillman; Alex H. Barnett; Per-Gunnar Martinsson

2014-06-01T23:59:59.000Z

273

Heavy Daily Precipitation Frequency over the Contiguous United States: Sources of Climatic Variability and Seasonal Predictability  

Science Journals Connector (OSTI)

By matching large-scale patterns in climate fields with patterns in observed station precipitation, this work explores seasonal predictability of precipitation in the contiguous United States for all seasons. Although it is shown that total ...

Alexander Gershunov; Daniel R. Cayan

2003-08-01T23:59:59.000Z

274

A Method for Evaluating the Application of Variable Frequency Drives with Coal Mine Ventilation Fans.  

E-Print Network (OSTI)

??The adjustable-pitch setting on an axial-flow fan is the most common method of controlling airflow for primary coal mine ventilation. With this method, the fan… (more)

Murphy, Tyson M.

2006-01-01T23:59:59.000Z

275

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

E-Print Network (OSTI)

and shorter time scales. A model utility test for the least squares fit of modeled to observed velocity shows that the second baroclinic mode is useful to the statistical model during 50 – 85 % of the mooring deployment, and is particularly necessary...

Cole, Kelly Lynne

2009-05-15T23:59:59.000Z

276

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

SciTech Connect

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

277

AC Loss Measurements on a 2G YBCO Coil  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES) to continue development of HTS power transformers. For compatibility with the existing power grid, a commercially viable HTS transformer will have to operate at high voltages in the range of 138 kV and above, and will have to withstand 550-kV impulse voltages as well. Second-generation (2G) YBCO coated conductors will be required for an economically-competitive design. In order to adequately size the refrigeration system for these transformers, the ac loss of these HTS coils must be characterized. Electrical AC loss measurements were conducted on a prototype high voltage (HV) coil with co-wound stainless steel at 60 Hz in a liquid nitrogen bath using a lock-in amplifier technique. The prototype HV coil consisted of 26 continuous (without splice) single pancake coils concentrically centered on a stainless steel former. For ac loss measurement purposes, voltage tap pairs were soldered across each set of two single pancake coils so that a total of 13 separate voltage measurements could be made across the entire length of the coil. AC loss measurements were taken as a function of ac excitation current. Results show that the loss is primarily concentrated at the ends of the coil where the operating fraction of critical current is the highest and show a distinct difference in current scaling of the losses between low current and high current regimes.

Rey, Christopher M [ORNL] [ORNL; Duckworth, Robert C [ORNL] [ORNL; Schwenterly, S W [ORNL] [ORNL

2011-01-01T23:59:59.000Z

278

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

279

Pressure-induced OH frequency downshift in brucite: frequency-distance and frequency-field correlations  

Science Journals Connector (OSTI)

The ordered Mg(OH)2 crystal structure has been optimized for different pressures in the pressure range 0-21 GPa, within the trigonal P m1 space group. Anharmonic frequencies for the Raman-active OH vibrational mode were calculated from potential energy curves obtained by B3LYP and PW91 calculations with the CRYSTAL06 program. We find that an external pressure leads to an OH frequency downshift, in agreement with experiment, but there are no hydrogen bonds involved. The frequency downshift depends linearly on the electric field exerted on the OH ions from its neighbours in the 'opposite' layer. In agreement with experiment we also find that the pressure-induced 'v(OH) vs. interlayer R(O - - - O)' curve deviates from the well established correlation curves for hydrogen-bonded systems in the literature; the ?v/?R slope for high pressure conditions is much smaller. We also point out the merits of reporting both v(OH) and ?vgas-to-solid for comparison with experiment.

K Hermansson; G Gajewski; P D Mitev

2008-01-01T23:59:59.000Z

280

Structure of the Surface Streamers of an AC Barrier Corona in Argon  

SciTech Connect

Results are presented from experimental studies of the structure of an ac surface discharge excited by a metal needle over a plane dielectric surface. A barrier corona discharge was ignited in atmospheric-pressure argon at frequencies of the applied sinusoidal voltage from 50 Hz to 30 kHz. In experiments, the area of a dielectric covered with the discharge plasma increased with applied voltage. The discharge structure in diffuse and streamer modes was recorded using a digital camera and a high-speed image tube operating in a frame mode. It is found that, in the positive and negative half-periods of the applied voltage, the structure of the surface discharge is substantially different. The statistical characteristics of the branching surface streamers in the positive and negative half-periods are determined as functions of the voltage frequency. The most intense lines in the emission spectrum of the barrier corona are determined for both half-periods. The correlation between the dynamics of the emission intensity and the dynamics of the discharge current and voltage is investigated.

Akishev, Yu.S.; Aponin, G.I.; Karal'nik, V.B.; Monich, A.E.; Trushkin, N.I. [Troitsk Institute for Innovation and Fusion Research, Troitsk, Moscow oblast, 142190 (Russian Federation)

2004-12-15T23:59:59.000Z

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281

Data:Ed495bde-91e5-416f-b491-ea26ac6bc0ad | Open Energy Information  

Open Energy Info (EERE)

Ed495bde-91e5-416f-b491-ea26ac6bc0ad Ed495bde-91e5-416f-b491-ea26ac6bc0ad No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: Western Area Power Administration (Arizona) Effective date: 2011/10/01 End date if known: Rate name: Regulation and Frequency Response Sector: Industrial Description: Source or reference: www.wapa.gov/dsw/pwrmkt/CRS/Current/Fy2012/RateSched.doc Source Parent: Comments Applicability Demand (kW) Minimum (kW): Maximum (kW): History (months): Energy (kWh) Minimum (kWh): Maximum (kWh): History (months): Service Voltage Minimum (V): Maximum (V): Character of Service Voltage Category: Phase Wiring:

282

E-Print Network 3.0 - ac metal-enclosed switchgear Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Anne 2011 Prsente devant Summary: -design; Transmission System; Life Cycle Assessment (LCA); 765 kV AC; 1000 kV AC; Ultra High Voltage; Extra High Voltage... Acidification AAC...

283

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

284

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

AVTA Voltec AC Level 1 and Level 2 Charging Systems Testing Results AVTA Voltec AC Level 1 and Level 2 Charging Systems Testing Results The Vehicle Technologies Office's Advanced...

285

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

286

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

287

Breathing HRV by the Concept of AC Ventilation  

NLE Websites -- All DOE Office Websites (Extended Search)

Breathing HRV by the Concept of AC Ventilation Breathing HRV by the Concept of AC Ventilation Speaker(s): Hwataik Han Date: July 10, 2007 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Thomas McKone Heat recovery ventilators are frequently used to save heating/cooling loads of buildings for ventilation. There are several types of HRV's, including a parallel plate type, a rotary type, a capillary type, and a heat pipe type. The breathing HRV is a heat recovery ventilator of a new kind using the concept of alternating-current ventilation. The AC ventilation is the ventilation with the airflow directions reversed periodically. It has an advantage of using a single duct system, for both supply and exhaust purposes. In order to develop a breathing HRV system, the thermal recovery performance should be investigated depending on many parameters, such as

288

Reading with fixed and variable character pitch  

Science Journals Connector (OSTI)

We compared the effects of fixed and variable (proportional) spacing on reading speeds and found variable pitch to yield better performance at medium and large character sizes and...

Arditi, Aries; Knoblauch, Kenneth; Grunwald, Ilana

1990-01-01T23:59:59.000Z

289

STATCOM-based voltage and frequency regulator for stand-alone asynchronous generator  

Science Journals Connector (OSTI)

This paper presents a STATCOM-based voltage and frequency regulation for stand-alone asynchronous generator feeding linear and nonlinear loads. The SEIG have inherent poor voltage and frequency regulation. The voltage and frequency depend upon the load current and power factor of the load with fixed excitation capacitor employing unregulated turbines. The changing consumer load requires variable reactive power compensation for excitation requirement. Consumer load contains harmonics and performance of SEIG is largely affected by these load harmonics. A current controlled voltage source inverter working as STATCOM is used for harmonic elimination, load balancing and variable reactive power compensation. A DC chopper with dump load is connected across DC bus capacitor to regulate varying consumer load. The control algorithm has been first co-simulated with processor in the loop (PIL) and then experimentally validated. The transient behaviour of developed prototype system for application and removal of balanced, unbalanced, nonlinear load is investigated.

Dheeraj Kumar Palwalia

2014-01-01T23:59:59.000Z

290

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

291

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

292

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

293

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

E-Print Network (OSTI)

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

Nakamura, Iku

294

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

295

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

296

DE-AC05-06OR23100 Section H  

NLE Websites -- All DOE Office Websites (Extended Search)

DE-AC05-06OR23100 DE-AC05-06OR23100 Section H - Page 1 of 29 PART I - SCHEDULE SECTION H SPECIAL CONTRACT REQUIREMENTS H.1 CONSECUTIVE NUMBERING (MAY 1997)......................................................................... 4 H.2 MODIFICATION AUTHORITY (MAY 1997) ....................................................................... 4 H.3 OVERSIGHT OF CONTRACTOR (OCT 2004)..................................................................... 4 H.4 SMALL BUSINESS SUBCONTRACTING PLAN (SEPT 1999)............................................ 5 H.5 SAFEGUARDS AND SECURITY AWARENESS PROGRAM (MAY 1997)........................ 5 H.6 QUALITY ASSURANCE SYSTEM ALTERNATE I (JUL 2004).......................................... 5 H.7 CONFIDENTIALITY OF INFORMATION (MAY 1997)...................................................... 6 H.8 INDIRECT

297

(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

298

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

299

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

300

METHODS OF RADIO-FREQUENCY CURRENT DRIVE  

E-Print Network (OSTI)

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

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

Heterodyne laser instantaneous frequency measurement system  

DOE Patents (OSTI)

A heterodyne laser instantaneous frequency measurement system is disclosed. The system utilizes heterodyning of a pulsed laser beam with a continuous wave laser beam to form a beat signal. The beat signal is processed by a controller or computer which determines both the average frequency of the laser pulse and any changes or chirp of th frequency during the pulse.

Wyeth, Richard W. (Livermore, CA); Johnson, Michael A. (Pleasanton, CA); Globig, Michael A. (Livermore, CA)

1989-01-01T23:59:59.000Z

302

Operating Reserves and Variable Generation  

SciTech Connect

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

303

Cosmological models with variable constants  

E-Print Network (OSTI)

The behavior of the constants, G,c,h,a,e,m and Lambda, considering them as variable, in the framework of a flat cosmological model with FRW symmetries described by a bulk viscous fluid and considering mechanisms of adiabatic matter creation are investigated. Within two models; one with radiation predominance and another of matter predominance, this behavior are studied.

J. A. Belinchon

1999-07-01T23:59:59.000Z

304

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

SciTech Connect

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

305

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

306

Wind Levelized Cost of Energy: A Comparison of Technical and Financing Input Variables  

NLE Websites -- All DOE Office Websites (Extended Search)

1 1 October 2009 Wind Levelized Cost of Energy: A Comparison of Technical and Financing Input Variables Karlynn Cory and Paul Schwabe National Renewable Energy Laboratory 1617 Cole Boulevard, Golden, Colorado 80401-3393 303-275-3000 * www.nrel.gov NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Operated by the Alliance for Sustainable Energy, LLC Contract No. DE-AC36-08-GO28308 Technical Report NREL/TP-6A2-46671 October 2009 Wind Levelized Cost of Energy: A Comparison of Technical and Financing Input Variables Karlynn Cory and Paul Schwabe Prepared under Task No. WER9.3550 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government.

307

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

308

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

309

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

310

Performance of convergence-based variable-gain control of optical storage drives  

Science Journals Connector (OSTI)

In this paper, a method for the performance assessment of a variable-gain control design for optical storage drives is proposed. The variable-gain strategy is used to overcome well-known linear control design trade-offs between low-frequency tracking properties and high-frequency noise sensitivity. A convergence-based control design is proposed that guarantees stability of the closed-loop system and a unique bounded steady-state response for any bounded disturbance. These favourable properties, guaranteed by virtue of convergence, allow for a unique performance evaluation of the control system. Moreover, technical conditions for convergence are derived for the variable-gain controlled system and a quantitative performance measure, taking into account both low-frequency tracking properties and high-frequency measurement noise sensitivity, is proposed. The convergence conditions together with the performance measure jointly constitute a design tool for tuning the parameters of the variable-gain controller. The resulting design is shown to outperform linear control designs.

N. van de Wouw; H.A. Pastink; M.F. Heertjes; A.V. Pavlov; H. Nijmeijer

2008-01-01T23:59:59.000Z

311

Allianz Climate Solutions ACS GmbH | Open Energy Information  

Open Energy Info (EERE)

Allianz Climate Solutions ACS GmbH Allianz Climate Solutions ACS GmbH Jump to: navigation, search Name Allianz Climate Solutions (ACS) GmbH Place Munich, Germany Zip 80802 Product Munich-based subsidiary of insurance and asset management provider Allianz SE. ACS acts as investment manager, service provider and advisor of climate solutions for Allianz Group and external customers. Coordinates 48.136415°, 11.577531° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":48.136415,"lon":11.577531,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

312

www.cardiff.ac.uk/annualreview2013 ANNUALREVIEW  

E-Print Network (OSTI)

www.cardiff.ac.uk/annualreview2013 2013 ANNUALREVIEW #12;2 The Way Forward outlines our ambition, I must mention one key project that has occupied the time and energy of many staff in Schools's energy challenges and tackling the lasting effects of industrial activity. Individuals too, were singled

Davies, Christopher

313

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

314

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

315

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

316

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

E-Print Network (OSTI)

www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Third Party Nuclear Liability 1207 Anthony Thomas and Raphael J. Heffron With a return to nuclear new build expected in the UK, the clarification of the position of a Supplier and their potential to be liable for nuclear damage is of vital

Aickelin, Uwe

317

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 in central and eastern Europe for nuclear power. This working paper notes that with the addition of 12 new significantly in favour of nuclear power. Furthermore several of these central and eastern EU countries have

Aickelin, Uwe

318

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

E-Print Network (OSTI)

www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Third Party Nuclear Liability: The Case Thomas and Raphael J. Heffron The law surrounding third party nuclear liability is important to all parties in the nuclear supply chain whether they are providing decommissioning services, project

Aickelin, Uwe

319

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

E-Print Network (OSTI)

) falls and energy prices rises in one country may have little effect at the world level. Next, we examinewww.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract The Economics of Energy (and Electricity) Demand-term trends of both energy and more specifically electricity consumption. This paper discusses some

Aickelin, Uwe

320

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

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
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321

Aircraft AC Generators: Hybrid System Modeling and Simulation  

E-Print Network (OSTI)

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

Koutsoukos, Xenofon D.

322

Contract No. DE-AC27-IORV15051  

NLE Websites -- All DOE Office Websites (Extended Search)

Testing TOTAL 67,635,770.56 27,484,734.04 Page 2 of 5 Contract No. DE-AC27-10RV15051 Modification No. 49 SF-30 Continuation 3. The table in Contract Clause B.1, Type...

323

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

324

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

325

www.abdn.ac.uk/study Global Health  

E-Print Network (OSTI)

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

Levi, Ran

326

http://stir.ac.uk/4o Why study Marketing?  

E-Print Network (OSTI)

http://stir.ac.uk/4o BA(Hons) Marketing #12;Why study Marketing? Every business has end users, then Marketing may be the right degree for you. The course As you progress through your Marketing degree, you in a business setting. Team work ­ working in a group is an essential part of your Marketing degree, both during

Little, Tony

327

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.

328

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

329

www.swansea.ac.uk Health & Safety Office  

E-Print Network (OSTI)

to a manageable / acceptable (safer) level. #12;www.swansea.ac.uk Health & Safety Office Hazard & Risk #12;www the control measures required to reduce or eliminate the risk to a manageable / acceptable (safer) level. #12 for hazard identification and associated Risk Assessment To be able to identify Hazards and recommend

Martin, Ralph R.

330

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

331

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 Description Model No. Capacity (tons) Space Heating Space Cooling SEER Water Heating Efficiency (E.F.)1 CEC Listing Date Heating Combined Hydronic HSPF E.F. Split Altherma LT ERLQ036

332

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

333

DE-AC27-08RV14800  

NLE Websites -- All DOE Office Websites (Extended Search)

SOLUTIONS LLC (A) (B) (C) (D) (E) (F) DE-AC27-08RV14800026 4. 1,860,841.43 for Rocky Flats Pension and PRB 5. 1,139,022.27 for Mound Pension and PRB and 6. 183,364.11...

334

Variable trim compressor – a new approach to variable compressor geometry  

Science Journals Connector (OSTI)

ABSTRACT Variable compressor geometry can be employed irrespective of the combustion process selected. It provides the capability of improving response behavior, reducing fuel consumption or cutting exhaust emissions from exhaust-gas turbocharged engines. Previous concepts on variable compressor geometries have been based on using inlet guide vanes to impart a swirl motion to the air that is fed to the compressor with the ultimate aim of enhancing the angle at which the flow of air enters the blade channel. This paper shows an inlet guide configuration that is based on a different operating principle. The inlet guide assembly shown here is designed in a way that minimizes any pressure losses even at high flow rates. Numerical studies were carried out using CFD to test the system's sensitivity. Based on these studies, a rigid conical element was then produced and the potential for increasing efficiency (up to 7% points) and shifting the surge line (up to 33%) verified on a turbocharger test bench. Finally, a design configuration is presented for a variable system.

P. Grigoriadis; S. Müller; A. Benz; M. Sens

2012-01-01T23:59:59.000Z

335

The characteristics of atmospheric radio frequency discharges with frequency increasing at a constant power density  

SciTech Connect

A computational model is used to investigate the characteristics of atmospheric radio frequency discharges by increasing frequency from 20 to 100 MHz at a constant power density. The simulation results show that increasing frequency can effectively enhance electron density before the transition frequency but after it the ignition is quenched then the electron density decreases. However this simulation also indicates the maximum time-averaged electron energy reduces monotonically with the excitation frequency increasing at a constant power density.

Zhang Yuantao; Li Qingquan; Lou Jie; Li Qingmin [School of Electrical Engineering, Shandong University, Jinan, Shandong Province 250061 (China)

2010-10-04T23:59:59.000Z

336

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

337

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

338

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

Science Journals Connector (OSTI)

Lately the atmospheric pressure jet type coronaplasma 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 pressurecoronaplasmacharacteristics 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.

Dan Bee Kim; H. Jung; B. Gweon; S. Y. Moon; J. K. Rhee; W. Choe

2011-01-01T23:59:59.000Z

339

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

340

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

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

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

342

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

343

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

344

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

345

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

346

High-Frequency Electrostatic Plasma Instabilities  

Science Journals Connector (OSTI)

A description of the stability properties of a plasma under the influence of an external electric field oscillating near the plasma frequency is presented.

J. P. Freidberg and B. M. Marder

1971-10-01T23:59:59.000Z

347

High-frequency, high-intensity photoionization  

Science Journals Connector (OSTI)

Two analytical methods for computing ionization by high-frequency fields are compared. Predicted ionization rates compare well, but energy predictions for the onset of ionization...

Reiss, H R

1996-01-01T23:59:59.000Z

348

Explosives detection with a frequency modulation spectrometer  

Science Journals Connector (OSTI)

An explosives detection instrument was designed and tested at SRI International. The instrument uses frequency modulation spectroscopy with midinfrared lead-salt diode lasers to...

Riris, H; Carlisle, C B; McMillen, D F; Cooper, D E

1996-01-01T23:59:59.000Z

349

Long-Period Solar Variability  

SciTech Connect

Terrestrial climate records and historical observations of the Sun suggest that the Sun undergoes aperiodic oscillations in radiative output and size over time periods of centuries and millenia. Such behavior can be explained by the solar convective zone acting as a nonlinear oscillator, forced at the sunspot-cycle frequency by variations in heliomagnetic field strength. A forced variant of the Lorenz equations can generate a time series with the same characteristics as the solar and climate records. The timescales and magnitudes of oscillations that could be caused by this mechanism are consistent with what is known about the Sun and terrestrial climate.

GAUTHIER,JOHN H.

2000-07-20T23:59:59.000Z

350

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

351

Variable pressure operation: An assessment  

SciTech Connect

This report summarizes the benefits, drawbacks, and technical issues of variable pressure operation (VPO) retrofit. Under VPO, turbine throttle pressure is reduced at low loads. This operating mode offers several significant advantages for units that cycle or operate at low loads for extended periods. Information used in the report was assembled from published sources, from major equipment manufacturers, and from utilities operating units under VPO in the US, Europe and Japan. The report also contains statistics of VPO use in this country and abroad. Design features of new units using VPO in Europe and Japan are presented to identify potential directions for future US designs incorporating VPO.

Kimel, E.; Kemeny, P.; Bierman, E.; Lagomarsino, J.; Clarke, D. (Burns and Roe, Inc., Oradell, NJ (USA))

1990-03-01T23:59:59.000Z

352

www.leeds.ac.uk/safety safety@leeds.ac.uk T:0113 34 34201 How can Health and Safety Services help you  

E-Print Network (OSTI)

www.leeds.ac.uk/safety safety@leeds.ac.uk T:0113 34 34201 How can Health and Safety Services help you: Health and Safety Services work in partnership with staff and the trade unions to help minimise with independent expertise and impartial advice. Each faculty/service group has an assigned Health and Safety

Haase, Markus

353

A group bridge approach for variable selection  

Science Journals Connector (OSTI)

......group bridge approach for variable...Actuarial Science, University...Department of Management Science, University...group bridge approach that is capable...group bridge approach for variable...Actuarial Science, University...Department of Management Science......

Jian Huang; Shuange Ma; Huiliang Xie; Cun-Hui Zhang

2009-06-01T23:59:59.000Z

354

Word length and frequency as determinants of stuttering  

Science Journals Connector (OSTI)

Word length and Frequency were independently varied to assess their effect on stuttering frequency. The list of test words contained ... low, medium of high frequency of occurrence. Stuttering frequency of 31 you...

I. M. Schlesinger; Rachel Melkman; Ron Levy

1966-06-01T23:59:59.000Z

355

DE-AC05-06OR23100  

NLE Websites -- All DOE Office Websites (Extended Search)

Section B - Page 1 of 10 Section B - Page 1 of 10 PART I - THE SCHEDULE SECTION B SUPPLIES OR SERVICES AND PRICES/COSTS B.1 ITEMS BEING ACQUIRED (ALTERNATE I) (OCT 2004) ................................... 3 B.2 ESTIMATED COST, BASE FEE, AND AWARD FEE (NOV 2004) ...................... 3 B.3 OPTION TO EXTEND THE CONTRACT (NOV 2004) .......................................... 6 B.4 OBLIGATION OF FUNDS (CPAF) (NOV 2004) ...................................................... 8 B.5 DETERMINATION OF AWARD FEE EARNED (NOV 2004) .............................. 9 DE-AC05-06OR23100 Section B - Page 2 of 10 Blank Page DE-AC05-06OR23100 Section B - Page 3 of 10 PART I - THE SCHEDULE SECTION B SUPPLIES OR SERVICES AND PRICES/COSTS B.1 ITEMS BEING ACQUIRED (ALTERNATE I) (OCT 2004)

356

SNL software manual for the ACS Data Analytics Project.  

SciTech Connect

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

357

AVTA: Aerovironment AC Level 2 Charging System Testing Results  

Energy.gov (U.S. Department of Energy (DOE))

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

358

Analysis and interpretation of ac impedance data for porous electrodes  

SciTech Connect

Ac impedance spectroscopy has been used to measure the dynamic response of two types of porous gas-diffusion oxygen electrodes in a sulfuric acid electrolyte. Models were developed based on flooded and on thin-film pore structure. The transfer functions of these structures were calculated and the impedance result fitted to the models using a nonlinear least squares program. The results were used to assess the adequacies of the models.

Springer, T.E.; Raistrick, I.D.

1987-01-01T23:59:59.000Z

359

AVTA: Clipper Creek AC Level 2 Charging System Testing Results  

Energy.gov (U.S. Department of Energy (DOE))

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

360

AVTA: Eaton AC Level 2 Charging System Testing Results  

Energy.gov (U.S. Department of Energy (DOE))

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

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

Variable Average Absolute Percent Differences  

U.S. Energy Information Administration (EIA) Indexed Site

Variable Variable Average Absolute Percent Differences Percent of Projections Over- Estimated Gross Domestic Product Real Gross Domestic Product (Average Cumulative Growth)* (Table 2) 1.0 42.6 Petroleum Imported Refiner Acquisition Cost of Crude Oil (Constant $) (Table 3a) 35.2 18.6 Imported Refiner Acquisition Cost of Crude Oil (Nominal $) (Table 3b) 34.7 19.7 Total Petroleum Consumption (Table 4) 6.2 66.5 Crude Oil Production (Table 5) 6.0 59.6 Petroleum Net Imports (Table 6) 13.3 67.0 Natural Gas Natural Gas Wellhead Prices (Constant $) (Table 7a) 30.7 26.1 Natural Gas Wellhead Prices (Nominal $) (Table 7b) 30.0 27.1 Total Natural Gas Consumption (Table 8) 7.8 70.2 Natural Gas Production (Table 9) 7.1 66.0 Natural Gas Net Imports (Table 10) 29.3 69.7 Coal Coal Prices to Electric Generating Plants (Constant $)** (Table 11a)

362

Instantaneous Measurement of Nonlocal Variables Lev Vaidman  

E-Print Network (OSTI)

Instantaneous Measurement of Nonlocal Variables Lev Vaidman 1 School of Physics and Astronomy variables related to two or more separate sites can be measured instantaneously, except for a finite time of the measurement. It is a verification measurement: it yields reliably the eigenvalues of the nonlocal variables

Vaidman, Lev

363

1 Pitch, Frequency, Musical Scales 1 1.1 Pitch and Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1  

E-Print Network (OSTI)

Contents ix 1 Pitch, Frequency, Musical Scales 1 1.1 Pitch and Frequency.2 Overtones, Pitch Equivalence, and Musical Scales . . . . . . . . . . . . . . . . . . . . . . . . 6 1.2.1 Pitch Equivalence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1

Walker, James S.

364

HF heating of a plasma column at frequencies below the electron cyclotron frequency  

Science Journals Connector (OSTI)

Dispersion of waves, excited by the helical structure in a plasma column and the heating of a tail of the electron distribution ... frequencies below the electron plasma and the electron cyclotron frequency.

J. ?atlov; V. Kopecký; J. Musil; F. Žá?ek; K. Novik

1978-01-01T23:59:59.000Z

365

Definition: Frequency Response | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Frequency Response Jump to: navigation, search Dictionary.png Frequency Response (Equipment) The ability of a system or elements of the system to react or respond to a change in system frequency. (System) The sum of the change in demand, plus the change in generation, divided by the change in frequency, expressed in megawatts per 0.1 Hertz (MW/0.1 Hz).[1] View on Wikipedia Wikipedia Definition Related Terms system, smart grid References ↑ Glossary of Terms Used in Reliability Standards An i LikeLike UnlikeLike You like this.Sign Up to see what your friends like. nline Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Frequency_Response&oldid=502580"

366

A Dual Tone Multiple Frequency receiver using a multiplexed OTA-C filter frequency detection architecture  

E-Print Network (OSTI)

A DUAL TONE MULTIPLE FREQUENCY RECEIVER USING A MULTIPLEXED OTA-C FILTER FREQUENCY DETECTION ARCHITECTURE A Thesis by GERALD WILLIAM GARCIA Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE August 1988 Major Subject: Electrical Engineering A DUAL TONE MULTIPLE FREQUENCY RECEIVER USING A MULTIPLEXED OTA-C FILTER FREQUENCY DETECTION ARCHITECTURE A Thesis by GERALD WILLIAM GARCIA Approved as to style...

Garcia, Gerald William

2012-06-07T23:59:59.000Z

367

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

SciTech Connect

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

368

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

369

Data:360311ac-6ca0-4146-89ac-db323120f125 | Open Energy Information  

Open Energy Info (EERE)

11ac-6ca0-4146-89ac-db323120f125 11ac-6ca0-4146-89ac-db323120f125 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: Northern States Power Co - Minnesota Effective date: 2012/05/01 End date if known: Rate name: LIMITED OFF PEAK SERVICE Transmission Transformed (Commercial & Industrial) Sector: Commercial Description: Available to any customers for controlled loads that will be energized only for the time period between 10:00 p.m. to 6:30 a.m. daily. DETERMINATION OF CUSTOMER BILLS Customer bills shall reflect energy charges (if applicable) based on customer's kWh usage, plus a customer charge (if applicable), plus demand charges (if applicable) based on customer's kW billing demand as defined. INTERIM RATE ADJUSTMENT A 4.49% Interim Rate Surcharge will be applied to rate components specified in the "Interim Rate Surcharge Rider." In addition, customer bills under this rate are subject to the following adjustments and/or charges. FUEL CLAUSE Bills are subject to the adjustments provided for in the Fuel Clause Rider. RESOURCE ADJUSTMENT Bills are subject to the adjustments provided for in the Conservation Improvement Program Adjustment Rider, the State Energy Policy Rate Rider, the Renewable Development Fund Rider, the Transmission Cost Recovery Rider, the Renewable Energy Standard Rider and the Mercury Cost Recovery Rider.

370

Non-Federal Participation in AC Intertie Final Environmental Impact Statement Volume2:Appendices  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Non-Federal Participation in AC Intertie Final Non-Federal Participation in AC Intertie Final Environmental Impact Statement Volume2:Appendices Bonneville DOE/eis- 0145 POWER ADMINISTRATION January 1994 Non-Federal Participation in AC Intertie Draft Environmental Impact Statement Table of Contents Appendix A Life-of-Facilities Capacity Ownership Proposal A1 Appendix B Long-Term Intertie Access Policy B1 Appendix C Glossary C1 Appendix D Biological Assessment ad Supporting Materials

371

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

372

Contract No.: DE-AC02-09CH11466 Section J Appendix I  

E-Print Network (OSTI)

Contract No.: DE-AC02-09CH11466 Section J ­ Appendix I M160 J-I-1 ATTACHMENT J.9 APPENDIX I DOE DIRECTIVES / LIST B Applicable to the Operation of PPPL Contract No. DE-AC02-09CH11466 #12;Modification 0160 Contract No.: DE-AC02-09CH11466 Section J ­ Appendix I J-I-2 DOE Directive Date Title ES&H O 150.1A 03

373

Contract No.: DE-AC02-09CH11466 ATTACHMENT J.4  

E-Print Network (OSTI)

Contract No.: DE-AC02-09CH11466 Section J Appendix D J-D-1 ATTACHMENT J.4 APPENDIX D BUDGET PROGRAM Applicable to the Operation of PPPL Contract No. DE-AC02-09CH11466 #12;Contract No.: DE-AC02-09CH11466 Section J Appendix D J-D-2 BUDGET PROGRAM This Appendix implements the clause of this contract entitled

Princeton Plasma Physics Laboratory

374

Contract No. DE-AC02-09CH11466 Section J Appendix G  

E-Print Network (OSTI)

Contract No. DE-AC02-09CH11466 Section J ­ Appendix G M135 J-G-1 ATTACHMENT J.7 APPENDIX G PURCHASING SYSTEM REQUIREMENTS Applicable to the Operation of PPPL Contract No. DE-AC02-09CH11466 #12;Contract No. DE-AC02-09CH11466 Section J ­ Appendix G M135 J-G-2 Appendix G Purchasing System Requirements

Princeton Plasma Physics Laboratory

375

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

376

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

SciTech Connect

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

377

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

SciTech Connect

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

378

Variable White Dwarf Data Tables  

SciTech Connect

Below, I give a brief explanation of the information in these tables. In all cases, I list the WD {number_sign}, either from the catalog of McCook {ampersand} Sion (1987) or determined by me from the epoch 1950 coordinates. Next, I list the most commonly used name (or alias), then I list the variable star designation if it is available. If not, I list the constellation name and a V** or?? depending on what the last designated variable star for that constellation is. I present epoch 2000 coordinates for all of the stars, which I precessed from the 1950 ones in most cases. I do not include proper motion effects; this is negligible for all except the largest proper motion DAV stars, such as L 19-2, BPM 37093, B 808, and G 29-38. Even in these cases, the error is no more than 30` in declination and 2 s in right ascension. I culled effective temperatures from the latest work (listed under each table); they are now much more homogeneous than before. I pulled the magnitude estimates from the appropriate paper, and they are mean values integrated over several cycles. The amplitude given is for the height of a typical pulse in the light curve. The periods correspond the dominant ones found in the light curve. In some cases, there is a band of power in a given period range, or the light curve is very complex, and I indicate this in the table. In the references, I generally list the paper with the most comprehensive pulsation analysis for the star in question. In some cases, there is more than one good reference, and I list them as well.

Bradley, P. A.

1997-12-31T23:59:59.000Z

379

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

SciTech Connect

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

380

CNV amplitude as a neural correlate for stuttering frequency: A case report of acquired stuttering  

Science Journals Connector (OSTI)

Abstract A neural hallmark of developmental stuttering is abnormal articulatory programming. One of the neurophysiological substrates of articulatory preparation is the contingent negative variation (CNV). Unfortunately, CNV tasks are rarely performed in persons who stutter and mainly focus on the effect of task variation rather than on interindividual variation in stutter related variables. However, variations in motor programming seem to be related to variation in stuttering frequency. The current study presents a case report of acquired stuttering following stroke and stroke related surgery in the left superior temporal gyrus. A speech related CNV task was administered at four points in time with differences in stuttering severity and frequency. Unexpectedly, CNV amplitudes at electrode sites approximating bilateral motor and left inferior frontal gyrus appeared to be inversely proportional to stuttering frequency. The higher the stuttering frequency, the lower the activity for articulatory preparation. Thus, the amount of disturbance in motor programming seems to determine stuttering frequency. At right frontal electrodes, a relative increase in CNV amplitude was seen at the test session with most severe stuttering. Right frontal overactivation is cautiously suggested to be a compensation strategy. In conclusion, late CNV amplitude elicited by a relatively simple speech task seems to be able to provide an objective, neural correlate of stuttering frequency. The present case report supports the hypothesis that motor preparation has an important role in stuttering.

Sarah Vanhoutte; John Van Borsel; Marjan Cosyns; Katja Batens; Pieter van Mierlo; Dimitri Hemelsoet; Dirk Van Roost; Paul Corthals; Miet De Letter; Patrick Santens

2014-01-01T23:59:59.000Z

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.


381

E-Print Network 3.0 - ac electrical conductivity Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

(2004) 1726 Highly conductive ordered heterogeneous ion-exchange membranes Summary: -exchange membranes was developed. It was found that application of an ac electric field... but...

382

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

NLE Websites -- All DOE Office Websites (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...

383

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

NLE Websites -- All DOE Office Websites (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...

384

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

NLE Websites -- All DOE Office Websites (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...

385

Bilateral field advantage in visual crowding Ramakrishna Chakravarthi a,c,*, Patrick Cavanagh b,c  

E-Print Network (OSTI)

Bilateral field advantage in visual crowding Ramakrishna Chakravarthi a,c,*, Patrick Cavanagh b, Hariharan, & Klein, 2002; Pelli, Palomares, & Majaj, 2004). Although several hypotheses have been put

Chakravarthi, Ramakrishna

386

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

NLE Websites -- All DOE Office Websites (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:...

387

Non-Federal Participation In Ac Intertie Final Environmental Impact Statement  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Non-Federal Participation In Ac Intertie Non-Federal Participation In Ac Intertie Final Environmental Impact Statement Volume 1: Environmental Analysis Bonneville DOE/eis-0145 POWER ADMINISTRATION January 1994 Non-Federal Participation in AC Intertie Final Environmental Impact Statement (DOE/EIS - 0145) Responsible Agency: U.S. Department of Energy, Bonneville Power Administration (BPA) Title of Proposed Action: Non-Federal Participation in AC Intertie States and Other Areas Involved: Washington, Oregon, Idaho, Montana, California, Nevada, Utah, New Mexico, Arizona, Wyoming, British Columbia Abstract: BPA is considering action in two areas: (1) non-Federal access to

388

Modeling and Experimental Investigation of a Variable Speed Drive Water Source Heat Pump  

Science Journals Connector (OSTI)

Accurate variable speed characteristics are needed for water source heat pumps (WSHP) to design variable speed controls to adjust refrigerant flow rates in heat pumps and air conditioners. The system capacity can then be regulated to match the compressor loads to the heating or cooling needs to improve the energy efficiency and lower energy costs. The motor and compression characteristics of WSHP were modeled to include the coupling between the motor speed and the torque characteristics and compression characteristics. An analytical model is given for a variable speed hermetic scroll compressor that describes various factors, such as the drive frequency, suction pressure, and discharge pressure as a function of the compressor speed. The model was validated experimentally using R22 and \\{R134a\\} in an experimental WSHP with variable speed control using frequency conversion. The results show that the analytical model properly describes the variable speed characteristics and provides a control strategy for adjusting the capacity of scroll compressors to match the heat pump or air conditioner operating conditions.

Zhifang Xue; Lin Shi

2010-01-01T23:59:59.000Z

389

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

390

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

391

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

392

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

SciTech Connect

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

393

Component external leakage and rupture frequency estimates  

SciTech Connect

In order to perform detailed internal flooding risk analyses of nuclear power plants, external leakage and rupture frequencies are needed for various types of components - piping, valves, pumps, flanges, and others. However, there appears to be no up-to-date, comprehensive source for such frequency estimates. This report attempts to fill that void. Based on a comprehensive search of Licensee Event Reports (LERs) contained in Nuclear Power Experience (NPE), and estimates of component populations and exposure times, component external leakage and rupture frequencies were generated. The remainder of this report covers the specifies of the NPE search for external leakage and rupture events, analysis of the data, a comparison with frequency estimates from other sources, and a discussion of the results.

Eide, S.A.; Khericha, S.T.; Calley, M.B.; Johnson, D.A.; Marteeny, M.L.

1991-11-01T23:59:59.000Z

394

Characterization of arcs in frequency domain  

SciTech Connect

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

D'Inca, R.; Siegl, G.; Faugel, H.; Braun, F.; Eckert, B.; Bobkov, V. [Max Planck Institut fuer Plasmaphysik, Garching, Germany, EURATOM Association (Germany); El Khaldi, M. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Noterdaeme, J.-M. [Max Planck Institut fuer Plasmaphysik, Garching, Germany, EURATOM Association (Germany); Gent University, EESA Department (Belgium)

2009-11-26T23:59:59.000Z

395

Spatial Frequency Filtering Using Nondelineated Thin Films  

Science Journals Connector (OSTI)

We present a new approach for achieving spatial frequency filtering in the analog domain. Our device, the Thin Film Spatial Filter, is a hybrid structure which combines the strengths of analog VLSI technology with the simplicity of a continuous sheet ...

J. Mcelvain; J. Langan; A. J. Heeger

1997-10-01T23:59:59.000Z

396

Laser Doppler vibrometer employing active frequency feedback  

SciTech Connect

We present a heterodyne Michelson interferometer for vibration measurement in which feedback is used to obviate the need to unwrap phase data. The Doppler shift of a vibrating target mirror is sensed interferometrically and compensated by means of a voltage-controlled oscillator driving an acousto-optic modulator. For frequencies within the servo bandwidth, the oscillator control voltage provides a direct measurement of the target velocity. Outside the servo bandwidth, phase-sensitive detection is used to evaluate high-frequency displacements. This approach is of great interest for the frequently-occurring situation where vibration amplitudes at low frequency exceed an optical wavelength, but knowledge of the vibration spectrum at high frequency is important as well.

Chijioke, Akobuije; Lawall, John

2008-09-20T23:59:59.000Z

397

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

398

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

399

Calibration for Frequencies of Stellar Spectral Lines  

E-Print Network (OSTI)

When studying the expansion of the universe, a significant problem is measuring the red shifts of stellar absorption lines with sufficiently high accuracy; this requires extremely accurate reference frequencies for calibration. An important recent...

Gomez, Juana

2010-07-14T23:59:59.000Z

400

Audio classification from time-frequency texture  

E-Print Network (OSTI)

Time-frequency representations of audio signals often resemble texture images. This paper derives a simple audio classification algorithm based on treating sound spectrograms as texture images. The algorithm is inspired ...

Slotine, Jean-Jacques E.

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

Plasma Paramagnetism in Radio-Frequency Fields  

Science Journals Connector (OSTI)

A study by experiment, simulation, and theory has found that a plasma responds paramagnetically to the external rf magnetic field applied perpendicular to the static magnetic field with frequency ?frequency. This effect can be exploited in the rf plugging and heating of plasmas; it explains the earlier rf plugging experiment (type-3 coil) of Watari et al. at Nagoya and possibly the rf heating experiment of Dikii et al. on the Uragan stellarator.

Y. Ohsawa; M. Inutake; T. Tajima; T. Hatori; T. Kamimura

1979-10-22T23:59:59.000Z

402

Extremely high frequency RF effects on electronics.  

SciTech Connect

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

403

Variable path length spectrophotometric probe  

DOE Patents (OSTI)

A compact, variable pathlength, fiber optic probe for spectrophotometric measurements of fluids in situ. The probe comprises a probe body with a shaft having a polished end penetrating one side of the probe, a pair of optic fibers, parallel and coterminous, entering the probe opposite the reflecting shaft, and a collimating lens to direct light from one of the fibers to the reflecting surface of the shaft and to direct the reflected light to the second optic fiber. The probe body has an inlet and an outlet port to allow the liquid to enter the probe body and pass between the lens and the reflecting surface of the shaft. A linear stepper motor is connected to the shaft to cause the shaft to advance toward or away from the lens in increments so that absorption measurements can be made at each of the incremental steps. The shaft is sealed to the probe body by a bellows seal to allow freedom of movement of the shaft and yet avoid leakage from the interior of the probe.

O'Rourke, Patrick E. (157 Greenwood Dr., Martiney, GA 30907); McCarty, Jerry E. (104 Recreation Dr., Aiken, SC 29803); Haggard, Ricky A. (1144 Thornwood Drive, North Augusta, SC 29891)

1992-01-01T23:59:59.000Z

404

HERSCHEL OBSERVATIONS OF CATACLYSMIC VARIABLES  

SciTech Connect

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

405

Definition: Variable Peak Pricing | Open Energy Information  

Open Energy Info (EERE)

Variable Peak Pricing Variable Peak Pricing Jump to: navigation, search Dictionary.png Variable Peak Pricing Variable Peak Pricing (VPP) is a hybrid of time-of-use and real-time pricing where the different periods for pricing are defined in advance (e.g., on-peak=6 hours for summer weekday afternoon; off-peak= all other hours in the summer months), but the price established for the on-peak period varies by utility and market conditions.[1] Related Terms real-time pricing References ↑ https://www.smartgrid.gov/category/technology/variable_peak_pricing [[C LikeLike UnlikeLike You like this.Sign Up to see what your friends like. ategory: Smart Grid Definitionssmart grid,off-peak,on-peak,smart grid, |Template:BASEPAGENAME]]smart grid,off-peak,on-peak,smart grid, Retrieved from "http://en.openei.org/w/index.php?title=Definition:Variable_Peak_Pricing&oldid=50262

406

Variable-Period Undulators for Synchrotron Radiation  

SciTech Connect

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

407

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

408

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

409

Integrating Variable Renewable Energy: Challenges and Solutions  

NLE Websites -- All DOE Office Websites (Extended Search)

Integrating Variable Renewable Energy: Challenges and Solutions L. Bird, M. Milligan, and D. Lew National Renewable Energy Laboratory Technical Report NRELTP-6A20-60451 September...

410

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

411

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

412

A molecular approach to combat spatio-temporal variation in insecticidal gene (Cry1Ac) expression in cotton  

Science Journals Connector (OSTI)

Spatio-temporal expression of an insecticidal gene (Cry1Ac) in pre existing transgenic lines of transgenic cotton was studied. Seasonal decline in expression of Cry1Ac differed significantly among different cotto...

Allah Bakhsh; Saima Siddique; Tayyab Husnain

2012-01-01T23:59:59.000Z

413

Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study  

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63E 63E Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study Peter Cappers, Andrew Mills, Charles Goldman, Ryan Wiser, Joseph H. Eto Environmental Energy Technologies Division October 2011 The work described in this report was funded by the Permitting, Siting and Analysis Division of the U.S. Department of Energy's Office of Electricity Delivery and Energy Reliability under Lawrence Berkeley National Laboratory Contract No. DE-AC02- 05CH11231. ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Disclaimer This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor The Regents of the

414

An entanglement rate for continuous variables and its application to a resonant optomechanical multimode setup  

E-Print Network (OSTI)

We introduce a general expression that quantifies the entanglement production rate in continuous variable systems in which entanglement depends on frequency. To exemplify its meaning and potential, we apply it to a four-mode optomechanical setup that enables the simultaneous up- and down-conversion of photons from a drive laser into entangled photon pairs. This setup is efficient in that both the drive and the optomechanical up- and down-conversion can be fully resonant.

Zhi Jiao Deng; Steven J. M. Habraken; Florian Marquardt

2014-06-30T23:59:59.000Z

415

A new approach for optimal sizing of battery energy storage system for primary frequency control of islanded Microgrid  

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Abstract This paper presents a method for determining optimal size of a battery energy storage system (BESS) for primary frequency control of a Microgrid. A Microgrid is assumed to be portion of a low voltage distribution feeder including sources such as microturbine, diesel generator, fuel cell and photovoltaic system with slow response for frequency control. A BESS due to its very fast dynamic response can play an important role in restoring balance between supply and demand. In this paper, overloading capacity of the BESS is employed for fast handling of the primary frequency control of a MG. To achieve this purpose, by considering overloading characteristics and limitations of the state of charge (SOC) of battery, a control scheme of dc/ac converter for the BESS is developed. Based on this scheme, overloading capacity of the BESS and its permissible duration for participating in primary frequency control is determined. Simulation studies are carried out using PSCAD/EMTDC software package to evaluate the performance of the proposed control scheme.

Mohammad Reza Aghamohammadi; Hajar Abdolahinia

2014-01-01T23:59:59.000Z

416

Data:A865370d-061c-4ac0-bad4-a28ee66d26ac | Open Energy Information  

Open Energy Info (EERE)

d-061c-4ac0-bad4-a28ee66d26ac d-061c-4ac0-bad4-a28ee66d26ac No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: City of St Marys, Ohio (Utility Company) Effective date: 2001/06/10 End date if known: Rate name: Commercial General Service Distribution Rate 128 Sector: Commercial Description: *This rate schedule is available for lighting and power for those customers establishing a minimum demand of 1,000 KW and who enter into a Service Agreement with the City for the purchase from the City of St. Marys for its electric energy requirements. Character of service:Service will be Three (3) Phase, Alternating Current, 60 Hertz, 12,470 Volts unregulated.

417

Data:537e7901-a057-48d1-ac7a-c08908a00772 | Open Energy Information  

Open Energy Info (EERE)

-a057-48d1-ac7a-c08908a00772 -a057-48d1-ac7a-c08908a00772 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: City of Jasper, Indiana (Utility Company) Effective date: 2009/09/01 End date if known: Rate name: Municipal Street Light (400 W Mercury Vapor) Sector: Lighting Description: Applicable only for street, alley and park lighting and traffic signals of the City of Jasper. Source or reference: ISU Documentation Source Parent: Comments Applicability Demand (kW) Minimum (kW): Maximum (kW): History (months): Energy (kWh) Minimum (kWh): Maximum (kWh): History (months): Service Voltage Minimum (V): Maximum (V):

418

Data:1f029483-379f-4568-ac06-8bd5cb1ac7b0 | Open Energy Information  

Open Energy Info (EERE)

3-379f-4568-ac06-8bd5cb1ac7b0 3-379f-4568-ac06-8bd5cb1ac7b0 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: Holy Cross Electric Assn, Inc Effective date: 2011/07/01 End date if known: Rate name: STREET, HIGHWAY AND AREA LIGHTING: 100 Watt HPS Sector: Lighting Description: This rate applies when all fixtures are mounted on Holy Cross wood poles, either primary or secondary. Source or reference: http://www.holycross.com/about-us/rates-charges Source Parent: Comments Applicability Demand (kW) Minimum (kW): Maximum (kW): History (months): Energy (kWh) Minimum (kWh): Maximum (kWh): History (months):

419

Data:D0f4ac6d-44e2-4291-93ac-7bad270f8d9b | Open Energy Information  

Open Energy Info (EERE)

ac6d-44e2-4291-93ac-7bad270f8d9b ac6d-44e2-4291-93ac-7bad270f8d9b No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: Cooperative L&P Assn Lake Cnty Effective date: 2012/01/01 End date if known: Rate name: Heat Pumps Sector: Residential Description: Both Air-source and Ground-source heat pumps use either the dual fuel or general service rate, depending on if you install a back-up heating system. Note: General service rates apply until back up fuel system is installed and operational. Contact your local heating contractor for any equipment information. Source or reference: http://www.clpower.com/?p=14

420

Data:304c7bdb-9ac5-4bea-ab51-af99e3f22ac3 | Open Energy Information  

Open Energy Info (EERE)

bdb-9ac5-4bea-ab51-af99e3f22ac3 bdb-9ac5-4bea-ab51-af99e3f22ac3 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: Cuming County Public Pwr Dist Effective date: 2011/12/14 End date if known: Rate name: Security Lighting Unmetered Lights 400W MV Sector: Lighting Description: Source or reference: Ilinois State University Rate binder # 10 Source Parent: Comments Applicability Demand (kW) Minimum (kW): Maximum (kW): History (months): Energy (kWh) Minimum (kWh): Maximum (kWh): History (months): Service Voltage Minimum (V): Maximum (V): Character of Service Voltage Category: Phase Wiring: << Previous 1 2 3 Next >>

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.
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to obtain the most current and comprehensive results.


421

Data:E710dbca-01f1-41b8-a2ac-9680233ac368 | Open Energy Information  

Open Energy Info (EERE)

dbca-01f1-41b8-a2ac-9680233ac368 dbca-01f1-41b8-a2ac-9680233ac368 No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: City of Stafford, Kansas (Utility Company) Effective date: End date if known: Rate name: E6 - 155 Horsepower Sector: Commercial Description: Source or reference: https://cas.sharepoint.illinoisstate.edu/grants/Sunshot/Lists/DATA%20ENTRY%20Rates%20Collected/Attachments/627/rate%20information%20for%20Stafford.pdf Source Parent: Comments Applicability Demand (kW) Minimum (kW): Maximum (kW): History (months): Energy (kWh) Minimum (kWh): Maximum (kWh): History (months): Service Voltage Minimum (V):

422

Data:Cd66912f-ac4c-4a5f-ac64-750948dd9b7f | Open Energy Information  

Open Energy Info (EERE)

2f-ac4c-4a5f-ac64-750948dd9b7f 2f-ac4c-4a5f-ac64-750948dd9b7f No revision has been approved for this page. It is currently under review by our subject matter experts. Jump to: navigation, search Loading... 1. Basic Information 2. Demand 3. Energy << Previous 1 2 3 Next >> Basic Information Utility name: Farmers' Electric Coop, Inc (New Mexico) Effective date: 2010/05/01 End date if known: Rate name: Small Commercial Sector: Commercial Description: Source or reference: Rate Binder#8 (Illinois State University) Source Parent: Comments Applicability Demand (kW) Minimum (kW): Maximum (kW): History (months): Energy (kWh) Minimum (kWh): Maximum (kWh): History (months): Service Voltage Minimum (V): Maximum (V): Character of Service Voltage Category: Phase Wiring: << Previous 1 2 3 Next >> << Previous

423

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

E-Print Network (OSTI)

Study of Ionic Conductivity Profiles of the Air Cathode of a PEMFC by AC Impedance Spectroscopy membrane fuel cell PEMFC cathode by ac impedance measurement at open-circuit potential conditions by impregnating a proton-conducting ionomer in the catalyst active layer of the cathode of a polymer electrolyte

424

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

425

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

426

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

427

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

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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

428

Penetration of ac magnetic field into bulk high-temperature superconductors: Experiment and simulation  

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Penetration of ac magnetic field into bulk high-temperature superconductors: Experiment from these models for high-temperature superconductors are observed at the op- eration in ac fields condi- tions is very important for correct modeling magnetic prop- erties of high-temperature

Paperno, Eugene

429

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.

430

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.

431

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

432

Superconducting Cables for a.c. and d.c. Power Transmission  

Science Journals Connector (OSTI)

...1973 research-article Superconducting Cables for a.c. and d.c. Power Transmission...power transmission lines. Some present cables are water cooled to increase their current...both a.c. and d.c. superconducting cables are described, with particular attention...

1973-01-01T23:59:59.000Z

433

Envera Variable Compression Ratio Engine  

SciTech Connect

Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new technologies are packaged together to provide the greatest gains at the least cost. Aggressive engine downsiz

Charles Mendler

2011-03-15T23:59:59.000Z

434

A New ACS Audio Course to help you understand and solve industrial and municipal waste-water problems ....  

Science Journals Connector (OSTI)

A New ACS Audio Course to help you understand and solve industrial and municipal waste-water problems .... ...

1982-08-01T23:59:59.000Z

435

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

SciTech Connect

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

436

Atmospheric glow discharges from the high-frequency to very high-frequency bands  

Science Journals Connector (OSTI)

This letter reports an experimental investigation of an atmospheric glow discharge in both the high-frequency (HF) band of 3–30 MHz and the very high frequency band of 30–300 MHz. At constant input power increased frequency is found to change little the electron density and to reduce slightly the electron excitation temperature. Significantly an eightfold frequency increase from 20 to 80 MHz leads to a 20-fold increase in the maximum plasma power without plasma constriction. The maximum power density of 355 ? W / cm 3 achieved at 80 MHz is far greater than those reported in the HF band.

J. L. Walsh; F. Iza; M. G. Kong

2008-01-01T23:59:59.000Z

437

Influence of excitation frequency on plasma parameters and etching characteristics of radio-frequency discharges  

Science Journals Connector (OSTI)

Abstract Plasma parameters such as electron density, electron-collision rate, resonance frequency and the bias voltage were shown to be important for the characterization of radio-frequency (RF) plasmas. By means of self-excited electron resonance spectroscopy (SEERS), the plasma parameters were compared at two different frequencies, 13.56 \\{MHz\\} and 40.68 MHz, in argon, oxygen, fluorine and their mixtures at low pressure. Upon increasing the generator frequency, more RF power has to be applied to achieve the same bias voltage. At the lower pressure, the bias voltage indicates the mean energy of the ions impacting on the substrate and causing damage at the surface. The experimental results show that generally more power was dissipated in the plasma instead of the sheath if the frequency of the substrate generator was decreased. This results in a significantly higher electron density at the higher frequency. The increase of mean ion energy, owing to lower sheath thickness, has to be taken into account as a second-order effect. In order to show the influence of frequency for process applications, the etch rate of SiO2 on silicon was determined in CF4. For the same generator power, there is no well-pronounced dependence of the etch rate of SiO2 on silicon (CF4) on the frequency. For the same bias voltage, the etch rate of SiO2 increases roughly with the frequency.

M. Klick; L. Eichhorn; W. Rehak; M. Kammeyer; H. Mischke

1999-01-01T23:59:59.000Z

438

Atmospheric glow discharges from the high-frequency to very high-frequency bands  

SciTech Connect

This letter reports an experimental investigation of an atmospheric glow discharge in both the high-frequency (HF) band of 3-30 MHz and the very high frequency band of 30-300 MHz. At constant input power, increased frequency is found to change little the electron density and to reduce slightly the electron excitation temperature. Significantly, an eightfold frequency increase from 20 to 80 MHz leads to a 20-fold increase in the maximum plasma power without plasma constriction. The maximum power density of 355 W/cm{sup 3} achieved at 80 MHz is far greater than those reported in the HF band.

Walsh, J. L.; Iza, F.; Kong, M. G. [Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom)

2008-12-22T23:59:59.000Z

439

Broadband low?frequency sound radiator with high?frequency pump resonator.  

Science Journals Connector (OSTI)

A new type of underwater low?frequency radiator is described. Operation of the radiator is based on the nonlinear conversion of high?frequency acoustic pump energy to low?frequency sound pulsation of the water volume of the open acoustic pump resonator. High?intensity pump waves in the resonator produce cavitation. Water containing bubbles is highly nonlinear (hundreds and even thousands of times more than pure water) and dispersive. Both of these factors and also the use of the pump resonator promote much stronger conversion of pump energy to low?frequency sound in comparison with a parametric radiator. The calculation of the acoustical characteristics is presented.

Dimitri M. Donskoy

1992-01-01T23:59:59.000Z

440

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

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

Choice set options affect the valuation of risky prospects Stian Reimers (stian.reimers@warwick.ac.uk)  

E-Print Network (OSTI)

.reimers@warwick.ac.uk) Neil Stewart (neil.stewart@warwick.ac.uk) Nick Chater (nick.chater@warwick.ac.uk) Department to deciding whether to invest in shares or bonds, we have to come to decisions based on the merits

Chater, Nick

442

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

443

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

444

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

SciTech Connect

This document contains the appendices for the accident sequence analysis of internally initiated events for the Peach Bottom, Unit 2 Nuclear Power Plant. This is one of the five plant analyses conducted as part of the NUREG-1150 effort for the Nuclear Regulatory Commission. The work performed and described here is an extensive reanalysis of that published in October 1986 as NUREG/CR-4550, Volume 4. It addresses comments from numerous reviewers and significant changes to the plant systems and procedures made since the first report. The uncertainty analysis and presentation of results are also much improved, and considerable effort was expended on an improved analysis of loss of offsite power. The content and detail of this report is directed toward PRA practitioners who need to know how the work was done and the details for use in further studies. The mean core damage frequency is 4.5E-6 with 5% and 95% uncertainty bounds of 3.5E-7 and 1.3E-5, respectively. Station blackout type accidents (loss of all ac power) contributed about 46% of the core damage frequency with Anticipated Transient Without Scram (ATWS) accidents contributing another 42%. The numerical results are driven by loss of offsite power, transients with the power conversion system initially available operator errors, and mechanical failure to scram. 13 refs., 345 figs., 171 tabs.

Kolaczkowski, A.M.; Cramond, W.R.; Sype, T.T.; Maloney, K.J.; Wheeler, T.A.; Daniel, S.L. (Science Applications International Corp., Albuquerque, NM (USA); Sandia National Labs., Albuquerque, NM (USA))

1989-08-01T23:59:59.000Z

445

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

446

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

447

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

448

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.

449

Frequency Instability Problems in North American Interconnections  

NLE Websites -- All DOE Office Websites (Extended Search)

Frequency Instability Problems in Frequency Instability Problems in North American Interconnections May 1, 2011 DOE/NETL-2011/1473 Frequency Instability Problems in North American Interconnections Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement,

450

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

451

AC transmission system planning choosing lines from a discrete set  

E-Print Network (OSTI)

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

Gilbertson, Eric W.

2013-04-24T23:59:59.000Z

452

LOFAR, a new low frequency radio telescope  

E-Print Network (OSTI)

LOFAR, the Low Frequency Array, is a large radio telescope consisting of approximately 100 soccer-field sized antenna stations spread over a region of 400 km in diameter. It will operate at frequencies from ~10 to 240 MHz, with a resolution at 240 MHz of better than an arcsecond. Its superb sensitivity will allow for studies of a broad range of astrophysical topics, including reionisation, transient radio sources and cosmic rays, distant galaxies and AGNs. In this contribution a status rapport of the LOFAR project and an overview of the science case is presented.

H. J. A. Rottgering

2003-09-19T23:59:59.000Z

453

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

454

Undulations from amplified low frequency surface waves  

SciTech Connect

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

455

Two-frequency excitation of hydrogen atoms  

Science Journals Connector (OSTI)

When a hydrogen atom in a state with principal quantum number ni is irradiated simultaneously with light of frequency ?L, nearly that required to produce a transition to a higher state with principal quantum number nf and with microwave radiation of frequency ?, the transition is very probable when the resonance condition ?L+k?=Ef-Ei is satisfied, the emission or absorption of the net number k of microwave photons just compensating for the detuning of the light from the resonance. This process is analyzed with the use of a forward scattering method and the results are used to discuss the experiments of Bayfield et al. on the excitation of hydrogen.

P. Stehle

1982-11-01T23:59:59.000Z

456

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

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

457

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

458

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

459

Science with the Frequency Agile Solar Radiotelescope  

E-Print Network (OSTI)

of Technology #12;EGU Meeting 2004 April 29 NJIT Center for Solar Terrestrial Research 2 / 30 #12;EGU MeetingScience with the Frequency Agile Solar Radiotelescope Dale E. Gary New Jersey Institute 2004 April 29 NJIT Center for Solar Terrestrial Research 3 / 30 FASR Instrument (Antennas) Three arrays

460

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

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

High-Frequency Transient Eddies and Blocking  

Science Journals Connector (OSTI)

In this paper we investigate the role of high-frequency transient eddies in the maintenance of the blocking high which occurred over Europe on 16-25 February 1979. Time-filtering is used to decompose the atmospheric large-scale flow into ...

Eero Holopainen; Carl Fortelius

1987-06-01T23:59:59.000Z

462

High-Frequency Conductivity of Degenerate Semiconductors  

Science Journals Connector (OSTI)

The problem of high-frequency conductivity of a degenerate semiconductor is investigated by a kinetic description. The finite duration of encounters is taken into account in a self-consistent fashion which properly includes collective effects. This treatment is an extension for quantum plasmas of the Dawson-Oberman method given for classical plasmas.

Amiram Ron and Narkis Tzoar

1963-09-01T23:59:59.000Z

463

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

464

The scaling of transport AC losses in Roebel cables with varying strand parameters  

Science Journals Connector (OSTI)

A Roebel cable is a good candidate for low-voltage windings in a high-temperature superconductor (HTS) transformer because of its high current-carrying capability and low AC loss. Transport AC loss measurements were carried out in 1.8 m long 15/5 (fifteen 5 mm wide strands) and 15/4 Roebel cables. The results were compared with those in many Roebel cables composed of 2 mm wide Roebel strands. Comparison of the AC losses hinted that the intrinsic difference in normalized transport AC losses is due to differences in the g/w (ratio of the horizontal gap between the Roebel strands over the Roebel strand width) values. The intrinsic difference was confirmed by measuring transport AC loss in a series of horizontally arranged parallel conductor pairs with various g values. A method to scale transport AC losses in Roebel cables with varying strand parameters was developed. The scaling method will be useful for a rough assessment of AC loss in one-layer solenoid winding coils, such as in a HTS transformer.

Zhenan Jiang; Mike Staines; Nicholas J Long; Rodney A Badcock; Chris Bumby; Evgeny Talantsev; Kent Hamilton; Robert G Buckley; Naoyuki Amemiya

2014-01-01T23:59:59.000Z

465

Copyright 1999 The Association of Universities for Research in Astronomy, Inc. All Rights Reserved. Instrument Science Report ACS 2000-03  

E-Print Network (OSTI)

relating to each item. The present ACS pipeline operations are described in ACS ISRs 99-03 (Hack), 99-04 (Mutchler et al) and 99-08 (Hack). #12;Instrument Science Report ACS 2000-03 2 II. The Geometric Issues ACS

Sirianni, Marco

466

Microsoft Word - AC Report Final LBNL format-2.docx  

NLE Websites -- All DOE Office Websites (Extended Search)

ERNEST ORLANDO LAWRENCE ERNEST ORLANDO LAWRENCE BERKELEY NATIONAL LABORATORY Cooling the Planet: Opportunities for Deployment of Superefficient Room Air Conditioners Nihar Shah 1 , Paul Waide 2 , Amol Phadke 1 LBNL-XXXX 1 Environmental Energy Technologies Division, International Energy Studies Group, Lawrence Berkeley National Laboratory 2 Navigant Consulting, Inc. This work was funded by the Bureau of Oceans and International Environmental and Scientific Affairs, U.S. Department of State, and administered by the U.S. Department of Energy in support of the Super-efficient Equipment and Appliance Deployment (SEAD) initiative through the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 i Disclaimer This document was prepared as an account of work sponsored by the United States Government in

467

DE-AC05-06OR23100  

NLE Websites -- All DOE Office Websites (Extended Search)

NOT SPECIFIED /OTHER NOT SPECIFIED /OTHER ___________ (x) x DE-AC05-06OR23100 copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted; or (c) By separate letter or telegram which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGEMENT TO BE RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR OFFER. If by virtue of this amendment you desire to change an offer already submitted, such change may be made by telegram or letter, provided each telegram or letter makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified. 041152224 OAK RIDGE ASSOCIATED UNIVERSITIES, INC.

468

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

469

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

2011-05-16T23:59:59.000Z

470

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

SciTech Connect

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

471

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

E-Print Network (OSTI)

and Problems . 2 Switching Transfer Function . 3 General Theory of PWM 4 Performance Measurement of PWM sc-dc Coverters 1 5 8 12 ALGORITHM OF DIRECT PULSEWIDTH MODULATION USED IN AC- DC COVERTER 14 SINGLE PHASE AC-DC PWM CONVERTERS . . 17 ac..., and ISPWM. 3. 1 Sinusoidal Pulsewidth Modulation (SPWM) SPWM is the most commonly used PWM technique. In SPWM as shown in Figure 1, the pulse widths are generated by comparing a carrier signal which is made of CARRIER REFERENCE 0 0 I . 0 1. 5 20 2. 5...

Zhang, Yuemin

2012-06-07T23:59:59.000Z

472

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

SciTech Connect

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

473

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

SciTech Connect

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

474

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

475

Hybrid permanent magnet and variable reluctance generator  

SciTech Connect

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

476

Variable Temperature Scanning Probe Microscope | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

EMSL's ultra-high vacuum, variable-temperature scanning probe microscope system, or UHV VT SPM, is a state-of-the-art surface science tool comprising multiple complementary...

477

Radio frequency ion source operated with field effect transistor based radio frequency system  

SciTech Connect

Characteristics of radio frequency (RF) plasma production are investigated using a field effect transistor inverter power supply as an RF wave source. With the frequency of around 0.3 MHz, an electron density over 10{sup 18} m{sup -3} is produced in argon plasma. Although lower densities are obtained in hydrogen plasma, it drastically increased up to 5x10{sup 18} m{sup -3} with an axial magnetic field of around 100 G applied in the driver region. Effects of the magnetic field and gas pressure are investigated in the RF produced plasma with the frequency of several hundred kilohertz.

Ando, A.; Komuro, A.; Matsuno, T. [Department of Electrical Engineering, Tohoku University, Sendai 980-8759 (Japan); Tsumori, K.; Takeiri, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan)

2010-02-15T23:59:59.000Z

478

Buoyancy-generated variable-density turbulence  

SciTech Connect

Both a one-point (engineering) and a two-point (spectral) model are tested against numerical data. Deficiencies in these variable-density models are disucssed and modifications are suggested. Attention is restricted to turbulent interactions of two miscible, incompressible Newtonian fluids of different densities. Departures from the limits of validity of the Boussinesq approximation are examined. Results of the buoyancy-generated turbulence are compared with variable-density model predictions. 3 figs, 6 refs.

Sandoval, D.L. [Los Alamos National Lab., NM (United States)]|[Washington Univ. (United States); Clark, T.T. [Los Alamos National Lab., NM (United States); Riley, J.J. [Washington Univ. (United States)

1996-06-01T23:59:59.000Z

479

Prctica 2. Anlisi descriptiva univariable: variables qualitatives  

E-Print Network (OSTI)

nominal SEXO. Codificada de tipus "numèrica" amb valors 1 i 2. Aquests valors s'etiqueten amb: 1 `Hombre": (1) Seleccionem la variable sexo i la col·loquem al requadre de "Variables". D'aquesta manera obtenim: Frecuencias [Conjunto_de_datos1] C:\\Archivos de programa\\SPSS\\GSS93 reducido.sav Estadísticos sexo Sexo del

Castellana, Natàlia

480

Prctica 2. Anlisi descriptiva univariable: variables qualitatives  

E-Print Network (OSTI)

nominal SEXO. Codificada de tipus "numèrica" amb valors 1 i 2. Aquests valors s'etiqueten amb: 1 `Hombre) Seleccionem la variable sexo i la col·loquem al requadre de "Variables". D'aquesta manera obtenim la taula de Estadísticos Sexo del entrevistado 1500 0 2 Válidos Perdidos N Moda sexo Sexo del entrevistado 641 42,7 42,7 42

Castellana, Natàlia

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

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

482

Copyright 1999 The Association of Universities for Research in Astronomy, Inc. All Rights Reserved. Instrument Science Report ACS 2001-10  

E-Print Network (OSTI)

. Instrument Science Report ACS 2001-10 ACS software tool development W.B. Sparks, W.J. Hack, M. Clampin-3 (Sparks et al). The ACS pipeline operations are described in ACS ISRs 99-03 (Hack), 99-04 (Mutchler et al) and 99-08 (Hack). #12;Instrument Science Report ACS 2001-10 2 PyDrizzle and calacs We expect OPUS 13

Sirianni, Marco

483

The cellular basis for parallel neural transmission of a high-frequency stimulus and its low-frequency envelope  

Science Journals Connector (OSTI)

...a sinusoidal electric organ discharge (EOD) that produces an electric field around...individual A. leptorhynchus maintain a stable EOD frequency (13), the species has a frequency...1,000 Hz. Two fish with widely spaced EOD frequencies will generate a high-frequency...

Jason W. Middleton; André Longtin; Jan Benda; Leonard Maler

2006-01-01T23:59:59.000Z

484

Periodic Flux Variability of Stars due to the Reflex Doppler Effect Induced by Planetary Companions  

E-Print Network (OSTI)

Upcoming space-based photometric satellites offer the possibility of detecting continuum flux variability at the micro-magnitude level. We show that the Doppler flux variability induced by the reflex motion of stars due to planetary companions has an amplitude of (3-alpha)K/c, where K is the reflex radial velocity amplitude and alpha is the logarithmic slope of source spectral flux in the observed frequency band. For many of the known close-in planetary systems with periods less than ~0.2 years, the periodic Doppler variability is of order a micromagnitude, and is significant relative to the variability caused by reflected light from the planetary companion. For companions with periods greater than ~0.2 years, the Doppler signal is larger than the reflected light signal. We show that the future photometric satellites should reach the sensitivity to detect this Doppler variability. In particular, the Kepler satellite should have the photon-noise sensitivity to detect at a signal-to-noise ratio > 5, all planets with minimum mass greater than 5 Jupiter masses, and periods less than 0.1 years around the 10,000 main-sequence stars with spectral types A through K and apparent magnitude V<12 in its field-of-view.

Abraham Loeb; B. Scott Gaudi

2003-03-10T23:59:59.000Z

485

Linking Synoptic-scale Climate Phenomena to Lake-Level Variability in the Lake Michigan-Huron Basin  

Science Journals Connector (OSTI)

Lake-level change in the mid-latitudes is causally linked to variability in precipitation and evaporation that are dynamically linked to cyclone passages and larger-scale atmospheric variability across temporal scales. Hence, lake-level variability is both a product of and a record of synoptic-scale climate variability. Here, a daily synoptic classification for 1956–1999 is used to evaluate historical Lake Michigan-Huron water levels in the context of changes in the frequency and intensity of synoptic-scale phenomena. The results demonstrate that both within-type evolution and shifts in the relative frequency of synoptic types contributed to precipitation and evaporation anomalies through the historical period with the former reflecting the importance of the Great Lakes in determining the regional climate. Shifts in the frequency and intensity of synoptic winter types are also demonstrated to be contributing anomalous precipitation and evaporation coincident with phases of lake level associated with the 30-year quasi-periodicity. The synoptic-scale mechanisms of lake-level change over longer time scales illuminated here can be used to infer information about past climate states and improve projections of lake level from model simulations.

Nathan J. Polderman; Sara C. Pryor

2004-01-01T23:59:59.000Z

486

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

487

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

488

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

489

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

490

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

491

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

E-Print Network (OSTI)

2009. Impact of Increased DFIG Wind Penetration on Powerreports/2009report/vittal_dfig_pserc_final_report_s-

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)

2010. Analysis of Wind Power and Load Data at Multiple Time2010. Analysis of Wind Power and Load Data at Multiple Time

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)

Sequence Load Flow Software (PSLF). http://www.gepower.com/utility_software/en/ge_pslf/index.htm. GE Energy. 2008.Sequence Load Flow (PSLF) for the Western Interconnection

Eto, Joseph H.

2011-01-01T23:59:59.000Z

494

Predicting the Effects of Short-Term Photovoltaic Variability on Power System Frequency for Systems with Integrated Energy Storage.  

E-Print Network (OSTI)

?? The percentage of electricity supplied by photovoltaic (PV) generators is steadily rising in power systems worldwide. This rise in PV penetration may lead to… (more)

Traube, Joshua White

2014-01-01T23:59:59.000Z

495

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

496

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

E-Print Network (OSTI)

Chen, Paul K Wright, and James Evans. Resonance frequency21] Christine C Ho, James W Evans, and Paul K Wright. Direct22] Christine C Ho, James W Evans, and Paul K Wright. Direct

Miller, Lindsay Margaret

2012-01-01T23:59:59.000Z

497

Do High-Frequency Eddies Contribute to Low-Frequency Teleconnection Tendencies?  

Science Journals Connector (OSTI)

An isentropic potential vorticity (PV) budget analysis is employed to examine the role of synoptic transients, advection, and nonconservative processes as forcings for the evolution of the low-frequency PV anomalies locally and those associated ...

Panos J. Athanasiadis; Maarten H. P. Ambaum

2010-02-01T23:59:59.000Z

498

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

499

Frequency-dependent conductivity of electron glasses  

Science Journals Connector (OSTI)

Results of dc and frequency-dependent conductivity in the quantum limit—i.e., ??>kBT—for a broad range of dopant concentrations in nominally uncompensated, crystalline phosphorous-doped silicon and amorphous niobium-silicon alloys are reported. These materials fall under the general category of disordered insulating systems, which are referred to as electron glasses. Using microwave resonant cavities and quasioptical millimeter-wave spectroscopy we are able to study the frequency-dependent response on the insulating side of the metal-insulator transition. We identify a quantum critical regime, a Fermi glass regime, and a Coulomb glass regime. Our phenomenological results lead to a phase diagram description, or taxonomy, of the electrodynamic response of electron glass systems.

E. Helgren; N. P. Armitage; G. Grüner

2004-01-13T23:59:59.000Z

500

The prevalent motor bearing premature failures due to the high frequency electric current passage  

Science Journals Connector (OSTI)

Abstract Bearing premature failures are prevalent in VFD (Variable Frequency Drives) motors. The three common symptoms of the modern bearing current appeared on the bearings of a group of pump motors. The bearing failure mechanisms have been studied from the tribological point of view. The natures of the three common symptoms have been uncovered. A hypothesis of the skin effect has been proposed to explain the three common symptoms. The discovery of the serial microcraters reveals the discharge with Fourier series features. The nature of the fluting patterns excluded the theories of both EDM (Electrical Discharge Machining) and discharge corrugation. VA (Vibration Analysis) detected the harmonics of the BPOR (Ball Pass Outer Ring) frequency which associated with the fluting on the outer raceway. This discovery may be applied to detect fluting in condition monitoring.

William Liu

2014-01-01T23:59:59.000Z