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Note: This page contains sample records for the topic "naire variable variable" 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 Screw Compressor, Variable Screw Compressor Suppliers ...  

U.S. Energy Information Administration (EIA)

Variable Screw Compressor Suppliers & air compressor Manufacturers Directory. Source Top Quality Variable Screw Compressor Suppliers, air ...

2

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

3

VARIABLE TIME DELAY MEANS  

DOE Patents (OSTI)

An electrically variable time delay line is described which may be readily controlled simuitaneously with variable impedance matching means coupied thereto such that reflections are prevented. Broadly, the delay line includes a signal winding about a magnetic core whose permeability is electrically variable. Inasmuch as the inductance of the line varies directly with the permeability, the time delay and characteristic impedance of the line both vary as the square root of the permeability. Consequently, impedance matching means may be varied similariy and simultaneously w:th the electrically variable permeability to match the line impedance over the entire range of time delay whereby reflections are prevented.

Clemensen, R.E.

1959-11-01T23:59:59.000Z

4

Estimated Global Hydrographic Variability  

Science Conference Proceedings (OSTI)

An estimate is made of the three-dimensional global oceanic temperature and salinity variability, omitting the seasonal cycle, both as a major descriptive element of the ocean circulation and for use in the error estimates of state estimation. ...

Gaël Forget; Carl Wunsch

2007-08-01T23:59:59.000Z

5

Understanding Biomass Feedstock Variability  

SciTech Connect

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

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

2013-01-01T23:59:59.000Z

6

Georeactor Variability and Integrity  

E-Print Network (OSTI)

As a deep-Earth energy source, the planetocentric nuclear-fission georeactor concept is on a more secure scientific footing than the previous idea related to the assumed growth of the inner core. Unlike previously considered deep-Earth energy sources, which are essentially constant on a human time-scale, variability in nuclear fission reactors can arise from changes in composition and/or position of fuel, moderators, and neutron absorbers. Tantalizing circumstantial evidence invites inquiry into the possibility of short-term planetocentric nuclear fission reactor variability. This brief communication emphasizes the importance of scientific integrity and highlights the possibility of variable georeactor power output so that these might be borne in mind in future investigations, especially those related to the Earth's heat flux.

J. Marvin Herndon

2005-10-04T23:59:59.000Z

7

Georeactor Variability and Integrity  

E-Print Network (OSTI)

As a deep-Earth energy source, the planetocentric nuclear-fission georeactor concept is on a more secure scientific footing than the previous idea related to the assumed growth of the inner core. Unlike previously considered deep-Earth energy sources, which are essentially constant on a human time-scale, variability in nuclear fission reactors can arise from changes in composition and/or position of fuel, moderators, and neutron absorbers. Tantalizing circumstantial evidence invites inquiry into the possibility of short-term planetocentric nuclear fission reactor variability. This brief communication emphasizes the importance of scientific integrity and highlights the possibility of variable georeactor power output so that these might be borne in mind in future investigations, especially those related to the Earth's heat flux.

Herndon, J M

2005-01-01T23:59:59.000Z

8

Modeling 18° Water Variability  

Science Conference Proceedings (OSTI)

Variability of 18° Water formation is investigated with an isopycnic-coordinate model of the North Atlantic. A 30-year spinup integration is used as a “control” experiment in which the upper water column in the Sargasso Sea is shown to be in ...

Robert Marsh; Adrian L. New

1996-06-01T23:59:59.000Z

9

Variable percentage sampler  

DOE Patents (OSTI)

A remotely operable sampler is provided for obtaining variable percentage samples of nuclear fuel particles and the like for analyses. The sampler has a rotating cup for a sample collection chamber designed so that the effective size of the sample inlet opening to the cup varies with rotational speed. Samples of a desired size are withdrawn from a flowing stream of particles without a deterrent to the flow of remaining particles.

Miller, Jr., William H. (Knoxville, TN)

1976-01-01T23:59:59.000Z

10

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

11

Variable laser attenuator  

SciTech Connect

The disclosure relates to low loss, high power variable attenuators comprng 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.

Foltyn, Stephen R. (Los Alamos, NM)

1988-01-01T23:59:59.000Z

12

Solar-type Variables  

E-Print Network (OSTI)

The rich acoustic oscillation spectrum in solar-type variables make these stars particularly interesting for studying fluid-dynamical aspects of the stellar interior. I present a summary of the properties of solar-like oscillations, how they are excited and damped and discuss some of the recent progress in using asteroseismic diagnostic techniques for analysing low-degree acoustic modes. Also the effects of stellar-cycle variations in low-mass main-sequence stars are addressed.

Houdek, Gunter

2009-01-01T23:59:59.000Z

13

Errors in all variables  

SciTech Connect

We present a thorough derivation of the posterior for the straight line fit employing the hyper-plane prior. For the example of the parabola we enlarge the scope to nonlinear problems, however simplify it to be solved resembling the straight line solution. Finally we come to the problem of determining the exponents of a scaling law, where in logarithmic form the scaling exponents are linear coefficients of logarithmic variables.

Preuss, R.; Dose, V. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2005-11-23T23:59:59.000Z

14

Jets with Variable R  

E-Print Network (OSTI)

We introduce a new class of jet algorithms designed to return conical jets with a variable Delta R radius. A specific example, in which Delta R scales as 1/pT, proves particularly useful in capturing the kinematic features of a wide variety of hard scattering processes. We implement this Delta R scaling in a sequential recombination algorithm and test it by reconstructing resonance masses and kinematic endpoints. These test cases show 10-20% improvements in signal efficiency compared to fixed Delta R algorithms. We also comment on cuts useful in reducing continuum jet backgrounds.

David Krohn; Jesse Thaler; Lian-Tao Wang

2009-03-02T23:59:59.000Z

15

Solar Irradiance Variability  

E-Print Network (OSTI)

The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation and the solar cycle. A part of the difficulty is that there are no other constant natural daytime sources to which the Sun's brightness can be compared. The discovery of solar irradiance variability rekindled a long-running discussion on how strongly the Sun affects our climate. A non-negligible influence is suggested by correlation studies between solar variability and climate indicators. The mechanism for solar irradiance variations that fits the observations best is that magnetic features at the solar surface, i.e. sunspots, faculae and the magnetic network, are responsible for almost all variations (although on short timescales convection and p-mode oscillations also contribute). In spite of significant progress important questions are still open. Thus there is a debat...

Solanki, Sami K

2012-01-01T23:59:59.000Z

16

Climate Variability, Fish, and Fisheries  

Science Conference Proceedings (OSTI)

Fish population variability and fisheries activities are closely linked to weather and climate dynamics. While weather at sea directly affects fishing, environmental variability determines the distribution, migration, and abundance of fish. ...

P. Lehodey; J. Alheit; M. Barange; T. Baumgartner; G. Beaugrand; K. Drinkwater; J.-M. Fromentin; S. R. Hare; G. Ottersen; R. I. Perry; C. Roy; C. D. van der Lingen; F. Werner

2006-10-01T23:59:59.000Z

17

Colorado River Basin Hydroclimatic Variability  

Science Conference Proceedings (OSTI)

An analysis of annual hydroclimatic variability in the Upper Colorado River basin (UCRB) for the period of 1906–2006 was performed to understand the dominant modes of multidecadal variability. First, wavelet-based spectral analysis was employed ...

Kenneth Nowak; Martin Hoerling; Balaji Rajagopalan; Edith Zagona

2012-06-01T23:59:59.000Z

18

Scalable analysis of variable software  

Science Conference Proceedings (OSTI)

The advent of variability management and generator technology enables users to derive individual variants from a variable code base based on a selection of desired configuration options. This approach gives rise to the generation of possibly billions ... Keywords: C Preprocessor, Liveness Analysis, Software Product Lines, Type Checking, Variability-aware Analysis

Jörg Liebig; Alexander von Rhein; Christian Kästner; Sven Apel; Jens Dörre; Christian Lengauer

2013-08-01T23:59:59.000Z

19

Variability within Modeling Language Definitions  

Science Conference Proceedings (OSTI)

We present a taxonomy of the variability mechanisms offered by modeling languages. The definition of a formal language encompasses a syntax and a semantic domain as well as the mapping that relates them, thus language variabilities are classified according ... Keywords: Modeling languages, UML, formal semantics, variability

María Victoria Cengarle; Hans Grönniger; Bernhard Rumpe

2009-10-01T23:59:59.000Z

20

Symmetrization Of Binary Random Variables  

E-Print Network (OSTI)

A random variable Y is called an independent symmetrizer of a given random variable X if (a) it is independent of X and (b) the distribution of X Y is symmetric about 0. In cases where the distribution of X is symmetric about its mean, it is easy to see that the constant random variable Y is a minimum-variance independent symmetrizer. Taking

Abram Kagan; Colin Mallows; Larry Shepp; Robert J. Vanderbei; Yehuda Vardi

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

VARIABLE TIME-INTERVAL GENERATOR  

DOE Patents (OSTI)

This patent relates to a pulse generator and more particularly to a time interval generator wherein the time interval between pulses is precisely determined. The variable time generator comprises two oscillators with one having a variable frequency output and the other a fixed frequency output. A frequency divider is connected to the variable oscillator for dividing its frequency by a selected factor and a counter is used for counting the periods of the fixed oscillator occurring during a cycle of the divided frequency of the variable oscillator. This defines the period of the variable oscillator in terms of that of the fixed oscillator. A circuit is provided for selecting as a time interval a predetermined number of periods of the variable oscillator. The output of the generator consists of a first pulse produced by a trigger circuit at the start of the time interval and a second pulse marking the end of the time interval produced by the same trigger circuit.

Gross, J.E.

1959-10-31T23:59:59.000Z

22

CDIAC Climate Data: Available Variables  

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

Climate Variables Available in CDIAC Data Products Temperature Precipitation Cloudiness Sunshine Duration Snowfall and Snow Depth Atmospheric Pressure Atmospheric Moisture Surface...

23

On Sub-ENSO Variability  

Science Conference Proceedings (OSTI)

Multichannel singular spectrum analysis (MSSA) of surface zonal wind, sea surface temperature (SST), 20° isotherm depth, and surface zonal current observations (between 1990 and 2004) identifies three coupled ocean–atmosphere modes of variability ...

Noel S. Keenlyside; Mojib Latif; Anke Dürkop

2007-07-01T23:59:59.000Z

24

Variable focal length deformable mirror  

DOE Patents (OSTI)

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

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

2007-06-12T23:59:59.000Z

25

Interannual Variability of the Global Radiation Budget  

Science Conference Proceedings (OSTI)

Interannual variability of the global radiation budget, regions that contribute to its variability, and what limits albedo variability are investigated using Clouds and the Earth’s Radiant Energy System (CERES) data taken from March 2000 through ...

Seiji Kato

2009-09-01T23:59:59.000Z

26

Operating Reserves and Variable Generation  

DOE Green Energy (OSTI)

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

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

2011-08-01T23:59:59.000Z

27

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. 1.

C. D. Impey; C. E. Petry; César Briceńo

2003-01-01T23:59:59.000Z

28

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.

Briceńo, C

2003-01-01T23:59:59.000Z

29

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

30

Lecture 2227 Continuous Random Variables  

E-Print Network (OSTI)

-x/100 dx = -e-x/100 100 0 = 1 - e-1 = .632 text typo Example 3 (Light Bulb): The lifetime X, in hours, of a certain kind of light bulb is a continuous random variable with density f(x) = 1500 x2 I(1500,) Check = 1 4 = p Let B denote the number of failures before 2000 hours among 5 light bulbs. Then P(B 1) = P

Scholz, Fritz

31

Lecture 2227 Continuous Random Variables  

E-Print Network (OSTI)

) = 100 0 1 100 e-x/100 dx = -e-x/100 100 0 = 1 - e-1 = .632 text typo Example 3 (Light Bulb): The lifetime X, in hours, of a certain kind of light bulb is a continuous random variable with density f 2000 1500 = 1 - 3 4 = 1 4 = p Let B denote the number of failures before 2000 hours among 5 light bulbs

Scholz, Fritz

32

Quantum computation and hidden variables  

E-Print Network (OSTI)

Many physicists limit oneself to an instrumentalist description of quantum phenomena and ignore the problems of foundation and interpretation of quantum mechanics. This instrumentalist approach results to "specialization barbarism" and mass delusion concerning the problem, how a quantum computer can be made. The idea of quantum computation can be described within the limits of quantum formalism. But in order to understand how this idea can be put into practice one should realize the question: "What could the quantum formalism describe?", in spite of the absence of an universally recognized answer. Only a realization of this question and the undecided problem of quantum foundations allows to see in which quantum systems the superposition and EPR correlation could be expected. Because of the "specialization barbarism" many authors are sure that Bell proved full impossibility of any hidden-variables interpretation. Therefore it is important to emphasize that in reality Bell has restricted to validity limits of the no- hidden-variables proof and has shown that two-state quantum system can be described by hidden variables. The later means that no experimental result obtained on two-state quantum system can prove the existence of superposition and violation of the realism. One should not assume before unambiguous experimental evidence that any two-state quantum system is quantum bit. No experimental evidence of superposition of macroscopically distinct quantum states and of a quantum bit on base of superconductor structure was obtained for the present. Moreover same experimental results can not be described in the limits of the quantum formalism.

V. V. Aristov; A. V. Nikulov

2010-07-12T23:59:59.000Z

33

Nonferromagnetic linear variable differential transformer  

DOE Patents (OSTI)

A nonferromagnetic linear variable differential transformer for accurately measuring mechanical displacements in the presence of high magnetic fields is provided. The device utilizes a movable primary coil inside a fixed secondary coil that consists of two series-opposed windings. Operation is such that the secondary output voltage is maintained in phase (depending on polarity) with the primary voltage. The transducer is well-suited to long cable runs and is useful for measuring small displacements in the presence of high or alternating magnetic fields.

Ellis, James F. (Powell, TN); Walstrom, Peter L. (Oak Ridge, TN)

1977-06-14T23:59:59.000Z

34

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)

35

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

36

DETECTING VARIABILITY IN MASSIVE ASTRONOMICAL TIME-SERIES DATA. II. VARIABLE CANDIDATES IN THE NORTHERN SKY VARIABILITY SURVEY  

SciTech Connect

We present variability analysis of data from the Northern Sky Variability Survey (NSVS). Using the clustering method, which defines variable candidates as outliers from large clusters, we cluster 16,189,040 light curves having data points at more than 15 epochs as variable and non-variable candidates in 638 NSVS fields. Variable candidates are selected depending on how strongly they are separated from the largest cluster and how rarely they are grouped together in eight-dimensional space spanned by variability indices. All NSVS light curves are also cross-correlated with IRAS, AKARI, Two Micron All Sky Survey, Sloan Digital Sky Survey (SDSS), and GALEX objects, as well as known objects in the SIMBAD database. The variability analysis and cross-correlation results are provided in a public online database, which can be used to select interesting objects for further investigation. Adopting conservative selection criteria for variable candidates, we find about 1.8 million light curves as possible variable candidates in the NSVS data, corresponding to about 10% of our entire NSVS sample. Multi-wavelength colors help us find specific types of variability among the variable candidates. Moreover, we also use morphological classification from other surveys such as SDSS to suppress spurious cases caused by blending objects or extended sources due to the low angular resolution of the NSVS.

Shin, Min-Su [Department of Astronomy, The University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Yi, Hahn; Kim, Dae-Won; Chang, Seo-Won [Department of Astronomy, Yonsei University, Seoul 120-749 (Korea, Republic of); Byun, Yong-Ik, E-mail: msshin@umich.edu, E-mail: yihahn@galaxy.yonsei.ac.kr, E-mail: dakim@cfa.harvard.edu, E-mail: seowony@galaxy.yonsei.ac.kr, E-mail: ybyun@yonsei.ac.kr [Department of Astronomy and University Observatory, Yonsei University, Seoul 120-749 (Korea, Republic of)

2012-03-15T23:59:59.000Z

37

Modeling the Effect of Land Surface Evaporation Variability on Precipitation Variability. Part I: General Response  

Science Conference Proceedings (OSTI)

This is the first of a two-part article that investigates the impact of land surface evaporation variability on the interannual variability of precipitation and compares it with the impact caused by sea surface temperature variability. Previous ...

Oreste Reale; Paul Dirmeyer

2002-08-01T23:59:59.000Z

38

Sources of Variability of Evapotranspiration in California  

Science Conference Proceedings (OSTI)

The variability (1990–2002) of potential evapotranspiration estimates (ETo) and related meteorological variables from a set of stations from the California Irrigation Management System (CIMIS) is studied. Data from the National Climatic Data ...

Hugo G. Hidalgo; Daniel R. Cayan; Michael D. Dettinger

2005-02-01T23:59:59.000Z

39

Incremental Closure of Free Variable Tableaux  

Science Conference Proceedings (OSTI)

This paper presents a technique for automated theorem proving with free variable tableaux that does not require backtracking. Most existing automated proof procedures using free variable tableaux require iterative deepening and backtracking over applied ...

Martin Giese

2001-06-01T23:59:59.000Z

40

Thermocline Variability in Different Dynamic Regions  

Science Conference Proceedings (OSTI)

The response of thermocline circulation to a variable wind forcing is investigated with quasigeostrophic models. The physical mechanism responsible for the different variability features in various dynamic regions has been highlighted. Special ...

Zhengye Liu

1996-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Studies on selection of controlled variables  

E-Print Network (OSTI)

Studies on selection of controlled variables by Vidar Alstad A Thesis Submitted for the Degree. Thus, the selection of controlled variables integrates the optimization and the control layer. Selecting the right controlled variables can be of paramount importance. Many chem­ ical processes

Skogestad, Sigurd

42

Studies on selection of controlled variables  

E-Print Network (OSTI)

Studies on selection of controlled variables by Vidar Alstad A Thesis Submitted for the Degree. Thus, the selection of controlled variables integrates the optimization and the control layer. Selecting the right controlled variables can be of paramount importance. Many chem- ical processes

Skogestad, Sigurd

43

Adaptive sampling for Bayesian variable selection  

E-Print Network (OSTI)

Adaptive sampling for Bayesian variable selection DAVID J. NOTT Department of Statistics for variable selection and for dealing with model un- certainty have become increasingly popular in recent consider adaptive Markov chain Monte Carlo schemes for Bayesian variable selection in Gaussian linear

Blennerhassett, Peter

44

Variable ratio regenerative braking device  

DOE Patents (OSTI)

Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

Hoppie, Lyle O. (Birmingham, MI)

1981-12-15T23:59:59.000Z

45

Variable residence time vortex combustor  

DOE Patents (OSTI)

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

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

1987-01-01T23:59:59.000Z

46

Rapid Oscillations in Cataclysmic Variables  

E-Print Network (OSTI)

I give an overview of the rich phenomenology of dwarf nova oscillations (DNOs) and Quasi-periodic Oscillations (QPOs) observed in cataclysmic variable stars (CVs). The favoured interpretation of these rapid brightness modulations (3 - >1000 s time scales) is that they are magnetic in nature - magnetically channelled accretion from the inner accretion disc for DNOs and possible magnetically excited travelling waves in the disc for QPOs. There is increasing evidence for the magnetic aspects, which extend to lower field the well known properties of strong field (polars) and intermediate strength field (intermediate polars) CVs. The result is that almost all CVs show the presence of magnetic fields on their white dwarf primaries - though for many the intrinsic field may be locally enhanced by the accretion process itself. There are many parallel behaviours with the QPOs seen in X-Ray binaries, with high and low frequency X-Ray QPOs resembling respectively the DNOs and QPOs in CVs.

Brian Warner

2003-12-06T23:59:59.000Z

47

Hard X-ray Variability of AGN  

E-Print Network (OSTI)

Aims: Active Galactic Nuclei are known to be variable throughout the electromagnetic spectrum. An energy domain poorly studied in this respect is the hard X-ray range above 20 keV. Methods: The first 9 months of the Swift/BAT all-sky survey are used to study the 14 - 195 keV variability of the 44 brightest AGN. The sources have been selected due to their detection significance of >10 sigma. We tested the variability using a maximum likelihood estimator and by analysing the structure function. Results: Probing different time scales, it appears that the absorbed AGN are more variable than the unabsorbed ones. The same applies for the comparison of Seyfert 2 and Seyfert 1 objects. As expected the blazars show stronger variability. 15% of the non-blazar AGN show variability of >20% compared to the average flux on time scales of 20 days, and 30% show at least 10% flux variation. All the non-blazar AGN which show strong variability are low-luminosity objects with L(14-195 keV) < 1E44 erg/sec. Conclusions: Concerning the variability pattern, there is a tendency of unabsorbed or type 1 galaxies being less variable than the absorbed or type 2 objects at hardest X-rays. A more solid anti-correlation is found between variability and luminosity, which has been previously observed in soft X-rays, in the UV, and in the optical domain.

V. Beckmann; S. D. Barthelmy; T. J. -L. Courvoisier; N. Gehrels; S. Soldi; J. Tueller; G. Wendt

2007-09-14T23:59:59.000Z

48

Envera Variable Compression Ratio Engine  

DOE Green Energy (OSTI)

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

49

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

50

Monitoring of Photovoltaic Plant Output and Variability  

Science Conference Proceedings (OSTI)

The performance of photovoltaic (PV) systems, including variability characteristics, is of increasing interest to utilities as they integrate more solar energy onto the electric grid. This study is part of a multi-year research series to investigate influencing factors that affect PV plant output, variability, and approaches to system management. It explores PV variability both from a grid perspective and through examination of project design aspects that can affect annual power production. ...

2012-12-12T23:59:59.000Z

51

Natural Gas Variability In California: Environmental Impacts...  

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

Natural Gas Variability In California: Environmental Impacts And Device Performance, Combustion Modeling of Pollutant Emissions From a Residential Cooking Range Title Natural Gas...

52

NREL: Transmission Grid Integration - Variability of Renewable...  

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

as variable generation sources because their electricity production varies based on the availability of wind and sun. However, they are not the only source of variation in a...

53

Variable-Period Undulators for Synchrotron Radiation  

DOE Patents (OSTI)

A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

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

2005-02-22T23:59:59.000Z

54

NERC Presentation: Accommodating High Levels of Variable Generation...  

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

high levels of variable electricity eneration. Variable resources are types of electric power generation that rely on an uncontrolled, "variable" fuel (e.g. wind, sunlight,...

55

The use of 'race' as a variable in biomedical research  

E-Print Network (OSTI)

a variable in biomedical research but mainly to monitor thea Variable in Biomedical Research A dissertation submittedVariable in Biomedical Research…………. Manifest, Operative and

Efstathiou, Sophia

2009-01-01T23:59:59.000Z

56

Grassmann Variables in Jordan Matrix Models  

E-Print Network (OSTI)

Here we demonstrate the emergence of Grassmann variables in matrix models based on the exceptional Jordan algebra. The Grassmann algebras are built naturally using the octonion algebra. We argue the appearance of Grassmann variables solidifies the relationship between supersymmetry and triality.

Michael Rios

2005-03-02T23:59:59.000Z

57

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network (OSTI)

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 COMBUSTIBLE LIQUIDS. DO NOT USE FOR: · Heating gas engines · Heating car batteries · Thawing refrigerator equipment Specifications Temperature Variable from 212° F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

58

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network (OSTI)

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 COMBUSTIBLE LIQUIDS. DO NOT USE FOR: · Heating gas engines · Heating car batteries · Thawing refrigerator equipment Specifications Temperature Variable from 212" F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

59

Internal Variability of Indian Ocean SST  

Science Conference Proceedings (OSTI)

A 40-yr integration of an eddy-resolving numerical model of the tropical Indian Ocean is analyzed to quantify the interannual variability that is caused by the internal variability of ocean dynamics. It is found that along the equator in the ...

Markus Jochum; Raghu Murtugudde

2005-09-01T23:59:59.000Z

60

Gradient based variable forgetting factor RLS algorithm  

Science Conference Proceedings (OSTI)

An accurate new variable forgetting factor recursive least-square adaptive algorithm is derived. An improved mean square behaviour analysis is presented, which shows that the theoretical analysis and the simulation results are close to each other. The ... Keywords: RLS algorithm, adaptive filters, variable forgetting factor

C. F. So; S. C. Ng; S. H. Leung

2003-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Variable orifice using an iris shutter  

DOE Patents (OSTI)

A variable orifice forming mechanism utilizing an iris shutter arrangement adapted to control gas flow, conductance in vacuum systems, as a heat shield for furnace windows, as a beam shutter in sputtering operations, and in any other application requiring periodic or continuously-variable control of material, gas, or fluid flow.

Beeman, Raymond (El Cerrito, CA); Brajkovich, Steven J. (Fremont, CA)

1978-01-01T23:59:59.000Z

62

Bond Graph Modeling Of Variable Structure Systems  

E-Print Network (OSTI)

The problem of describing variable structure models in a compact, object--oriented fashion is revisited and analyzed from the perspective of bond graph modeling. Traditionally, bond graphs have always been used to describe continuous-- time physical processes with a fixed structure. Yet, this paper shall demonstrate that bond graphs are equally suitable to describe variable structure models as fixed structure models. Moreover, a bond graph description of variable structure models can teach us a lot about the essential properties of variable structure models, properties that are not easily visible when other modeling approaches are taken. The paper discusses issues related to causality reassignment and conditional index changes as a consequence of switching in a physical system. Keywords: Bond graphs, variable structure system, computational causality, conditional index change, switching, object--oriented modeling, Dymola. INTRODUCTION When the causality strokes were added to the forme...

François E. Cellier; Martin Otter; Hilding Elmqvist

1995-01-01T23:59:59.000Z

63

Energy Savings of Variable Speed Motors  

E-Print Network (OSTI)

This paper investigates the energy savings available by utilizing variable speed motors on pump and fan applications. Conventional control of flow or pressure in process plants is normally accomplished by throttling the various streams with control valves. Depending on the system and the actual operating conditions, this throttling may consume a considerable amount of energy. The hydraulics of different systems are investigated to generalize high energy saving applications. Typical pump characteristics at varying speeds are investigated since most performance curves are only available at a constant speed. The various types of variable speed electric motors are discussed. However, the primary variable speed system recommended is a variable frequency speed system which utilizes standard induction motors. Specific cases of centrifugal pump applications and cooling tower fan service are presented. Turndown frequencies, stream factors, and electric rates are included in the evaluation. The energy savings of a variable speed system becomes significant when flow rates vary widely and the electrical rates are high.

Fishel, F. D.

1979-01-01T23:59:59.000Z

64

Nine New Variable Stars in Camelopardalis  

E-Print Network (OSTI)

Nine new short period variable stars have been discovered in the direction of the open cluster Cr464 in Camelopardalis. The field was observed using Tzec Maun Observatory's telescope AP180. Two new variable stars were classified as pulsating stars (RRab and RRc types). The other seven stars are binary systems. One of them is of ELL-type, four binaries were recognized as EW-type, and two systems are rather short period EA-type binaries. All new variables were registered in the VSX catalogue.

Virnina, Natalia A

2013-01-01T23:59:59.000Z

65

Variability of EGRET Gamma-Ray Sources  

E-Print Network (OSTI)

The variability of the high-energy gamma ray sources in the Third EGRET catalog is analyzed by a new method. We re-analyze the EGRET data to calculate a likelihood function for the flux of each source in each observation, both for detections and upper limits. These functions can be combined in a uniform manner with a simple model of the flux distribution to characterize the flux variation by a confidence interval for the relative standard deviation of the flux. The main result is a table of these values for almost all the cataloged sources. As expected, the identified pulsars are steady emitters and the blazars are mostly highly variable. The unidentified sources are heterogeneous, with greater variation at higher Galactic latitude. There is an indication that pulsar wind nebulae are associated with variable sources. There is a population of variable sources along the Galactic plane, concentrated in the inner spiral arms.

P. L. Nolan; W. F. Tompkins; I. A. Grenier; P. F. Michelson

2003-07-10T23:59:59.000Z

66

Interannual Variability of Northwest Australian Tropical Cyclones  

Science Conference Proceedings (OSTI)

Tropical cyclone (TC) activity over the southeast Indian Ocean has been studied far less than other TC basins, such as the North Atlantic and northwest Pacific. The authors examine the interannual TC variability of the northwest Australian (NWAUS)...

Kevin H. Goebbert; Lance M. Leslie

2010-09-01T23:59:59.000Z

67

Variability of Southern Ocean Jets Near Topography  

Science Conference Proceedings (OSTI)

The interaction of jets with topography in the Southern Ocean is investigated using 19 years of altimetry data. In particular, the “jet jumping” mode of variability, by which two or more jets passing close to the same topographic feature show ...

Christopher C. Chapman; Rosemary Morrow

68

Weather Noise Forcing of Surface Climate Variability  

Science Conference Proceedings (OSTI)

A model-based method to evaluate the role of weather noise forcing of low-frequency variability of surface properties, including SST, surface currents, land surface temperature, and soil moisture, is presented. In this procedure, an “interactive ...

Edwin K. Schneider; Meizhu Fan

2007-09-01T23:59:59.000Z

69

Experiments Concerning Variability among Subjective Analyses  

Science Conference Proceedings (OSTI)

The variability of subjective (hand) analyses is explored by examining the results of two synoptic laboratory experiments. Two groups of analysts participated in the first experiment, one consisting of 13 senior meteorology students (1977), the ...

Dayton G. Vincent; Herbert Borenstein

1980-10-01T23:59:59.000Z

70

Tropical Convective Variability as 1/f Noise  

Science Conference Proceedings (OSTI)

Evidence is presented that the tropical convective variability behaves as 1/f noise for a 1–30-day period. This behavior is shown by analyzing the time series of convective available potential energy, which measures the degree of convective ...

Jun-Ichi Yano; Klaus Fraedrich; Richard Blender

2001-09-01T23:59:59.000Z

71

Optimizing Crop Insurance under Climate Variability  

Science Conference Proceedings (OSTI)

This paper studies the selection of optimal crop insurance under climate variability and fluctuating market prices. A model was designed to minimize farmers’ expected losses (including insurance costs) while using the conditional-value-at-risk ...

Juan Liu; Chunhua Men; Victor E. Cabrera; Stan Uryasev; Clyde W. Fraisse

2008-10-01T23:59:59.000Z

72

Variable volume architecture : expanding the boundary  

E-Print Network (OSTI)

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

Saheba, Asheshh (Asheshh Mohit), 1972-

2001-01-01T23:59:59.000Z

73

Backscatter Differential Phase—Estimation and Variability  

Science Conference Proceedings (OSTI)

On the basis of simulations and observations made with polarimetric radars operating at X, C, and S bands, the backscatter differential phase ? has been explored; ? has been identified as an important polarimetric variable that should not be ...

Silke Trömel; Matthew R. Kumjian; Alexander V. Ryzhkov; Clemens Simmer; Malte Diederich

2013-11-01T23:59:59.000Z

74

Spatial Variability of Outgoing Longwave Radiation  

Science Conference Proceedings (OSTI)

Data from the Earth Radiation Budget Experiment scanning radiometer aboard the NOAA-9 operational meteorological satellite are used to investigate the spatial variability of outgoing longwave radiation (OLR). Daily and monthly radiation maps at ...

G. Louis Smith; David Rutan

1994-07-01T23:59:59.000Z

75

Climate Variability and Sugarcane Yield in Louisiana  

Science Conference Proceedings (OSTI)

This paper seeks to understand the role that climate variability has on annual yield of sugarcane in Louisiana. Unique features of sugarcane growth in Louisiana and nonclimatic, yield-influencing factors make this goal an interesting and ...

David Greenland

2005-11-01T23:59:59.000Z

76

Integrating Variable Renewable Energy: Challenges and Solutions  

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

LLC This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.govpublications. Contract No. DE-AC36-08GO28308 Integrating Variable...

77

Dirac equation in terms of hydrodynamic variables  

E-Print Network (OSTI)

The distributed system $\\mathcal{S}_D$ described by the Dirac equation is investigated simply as a dynamic system, i.e. without usage of quantum principles. The Dirac equation is described in terms of hydrodynamic variables: 4-flux $j^{i}$, pseudo-vector of the spin $S^{i}$, an action $\\hbar \\phi $ and a pseudo-scalar $\\kappa $. In the quasi-uniform approximation, when all transversal derivatives (orthogonal to the flux vector $j^i$) are small, the system $\\mathcal{S}_D$ turns to a statistical ensemble of classical concentrated systems $\\mathcal{S}_{dc}$. Under some conditions the classical system $\\mathcal{S}_{dc}$ describes a classical pointlike particle moving in a given electromagnetic field. In general, the world line of the particle is a helix, even if the electromagnetic field is absent. Both dynamic systems $\\mathcal{S}_D$ and $\\mathcal{S}_{dc}$ appear to be non-relativistic in the sense that the dynamic equations written in terms of hydrodynamic variables are not relativistically covariant with respect to them, although all dynamic variables are tensors or pseudo-tensors. They becomes relativistically covariant only after addition of a constant unit timelike vector $f^{i}$ which should be considered as a dynamic variable describing a space-time property. This "constant" variable arises instead of $\\gamma $-matrices which are removed by means of zero divizors in the course of the transformation to hydrodynamic variables. It is possible to separate out dynamic variables $\\kappa $, $\\kappa ^i$ responsible for quantum effects. It means that, setting $\\kappa ,\\kappa ^i\\equiv 0$, the dynamic system $\\mathcal{S}_D$ described by the Dirac equation turns to a statistical ensemble $\\mathcal{E}_{Dqu}$ of classical dynamic systems $\\mathcal{S}_{dc}$.

Yuri A. Rylov

2011-01-31T23:59:59.000Z

78

Variables et categories grammaticales dans un modele ariane  

Science Conference Proceedings (OSTI)

Toutes tes catégories grammaticales utilisées dans un modéle de traduction ariane sont formalisées et codées de faç mnémonique en tant que variables et valeurs de variables. L'ensemble des variables d'un ...

Jean-Phillippe Guilbaud

1986-08-01T23:59:59.000Z

79

Reversible Record Breaking and Variability: Temperature Distributions across the Globe  

Science Conference Proceedings (OSTI)

Based on counts of record highs and lows, and employing reversibility in time, an approach to examining natural variability is proposed. The focus is on intrinsic variability; that is, variance separated from the trend in the mean. A variability ...

Amalia Anderson; Alexander Kostinski

2010-08-01T23:59:59.000Z

80

U.S. Economic Sensitivity to Weather Variability  

Science Conference Proceedings (OSTI)

To estimate the economic effects of weather variability in the United States, the authors define and measure weather sensitivity as the variability in economic output that is attributable to weather variability, accounting for changes in technology and ...

Jeffrey K. Lazo; Megan Lawson; Peter H. Larsen; Donald M. Waldman

2011-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Variable pressure power cycle and control system  

DOE Patents (OSTI)

A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.

Goldsberry, Fred L. (Spring, TX)

1984-11-27T23:59:59.000Z

82

Integrating Variable Renewable Energy: Challenges and Solutions  

SciTech Connect

In the U.S., a number of utilities are adopting higher penetrations of renewables, driven in part by state policies. While power systems have been designed to handle the variable nature of loads, the additional supply-side variability and uncertainty can pose new challenges for utilities and system operators. However, a variety of operational and technical solutions exist to help integrate higher penetrations of wind and solar generation. This paper explores renewable energy integration challenges and mitigation strategies that have been implemented in the U.S. and internationally, including forecasting, demand response, flexible generation, larger balancing areas or balancing area cooperation, and operational practices such as fast scheduling and dispatch.

Bird, L.; Milligan, M.; Lew, D.

2013-09-01T23:59:59.000Z

83

Adaptive variable structure control law for a variable speed wind turbine  

Science Conference Proceedings (OSTI)

The efficiency of the wind power conversions systems can be greatly improved using an appropriate control algorithm. In this work, an adaptive robust control for a doubly feed induction generator drive for variable speed wind power generation is described. ... Keywords: modeling and simulation, variable structure control, wind turbine control

Oscar Barambones; Jose Maria Gonzalez De Durana; Patxi Alkorta; Jose Antonio Ramos; Manuel De La Sen

2011-05-01T23:59:59.000Z

84

Flight Control Design for Rotorcraft with Variable Rotor Speed.  

E-Print Network (OSTI)

??Flight control design issues for rotorcraft with variable rotor speed are investigated, and new design methodologies are developed to deal with the challenges of variable… (more)

Guo, Wei

2009-01-01T23:59:59.000Z

85

Adaptation to Climate Variability and Change: A Guidance Manual...  

Open Energy Info (EERE)

Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Jump to: navigation, search Tool Summary Name: Adaptation to Climate Variability and...

86

2005 RECS Variable Response Code Labels - U.S. Energy ...  

U.S. Energy Information Administration (EIA)

7 concrete or concrete block 8 glass 9 other 10 indescribable : 1 . 2005 recs variable response code labels . variable response code label file number* cnfrmhuq .

87

Interannual Variability of Indian Ocean Heat Transport  

Science Conference Proceedings (OSTI)

The work in this paper builds upon the relatively well-studied seasonal cycle of the Indian Ocean heat transport by investigating its interannual variability over a 41-yr period (1958–98). An intermediate, two-and-a-half-layer thermodynamically ...

Galina Chirokova; Peter J. Webster

2006-03-01T23:59:59.000Z

88

Variables optimization of building air conditioning system  

Science Conference Proceedings (OSTI)

A heating and climatizer system based on selective absorption of solar energy by a selective collector. The experimental study shows that the performance of this system depends on several variables: the nature of the colporteur fluid, the flow of the ... Keywords: heating and climatisation, modelation and optimization, solar energy

Marius-Constantin Popescu; Cornelia Aida Bulucea; Gheorghe Manolea; Cristian Vladu

2009-10-01T23:59:59.000Z

89

The Interannual Variability of Tropical Cyclones  

Science Conference Proceedings (OSTI)

This paper examines the interannual variability of tropical cyclones in each of the earth’s cyclone basins using data from 1985 to 2003. The data are first analyzed using a Monte Carlo technique to investigate the long-standing myth that the ...

William M. Frank; George S. Young

2007-10-01T23:59:59.000Z

90

Reuse and variability in large software applications  

Science Conference Proceedings (OSTI)

Reuse has always been a major goal in software engineering, since it promises large gains in productivity, quality and time to market reduction. Practical experience has shown that substantial reuse has only successfully happened in two cases: libraries, ... Keywords: AOP, COTS, EAI, MDA, interoperability, model driven software engineering, process driven application, product families, product line, reuse, variability, workflow

Jacky Estublier; German Vega

2005-09-01T23:59:59.000Z

91

Cloud service selection based on variability modeling  

Science Conference Proceedings (OSTI)

The selection among Cloud services is a recent problem in research and practice. The diversity of decision-relevant criteria, configurability of Cloud services and the need to involve human decision-makers require holistic support through models, methodologies ... Keywords: cloud service selection, decision-making, feature modeling, variability modeling

Erik Wittern; Jörn Kuhlenkamp; Michael Menzel

2012-11-01T23:59:59.000Z

92

Mesoscale Time and Space Wind Variability  

Science Conference Proceedings (OSTI)

The results of a program to study the time and space variability of the wind field below 5 km are presented. Wind data were collected using pilot balloons tracked with the METRAC positioning system. Balloons were launched at 10-30 min intervals ...

W. H. Jasperson

1982-06-01T23:59:59.000Z

93

Anatomy of North Pacific Decadal Variability  

Science Conference Proceedings (OSTI)

A systematic analysis of North Pacific decadal variability in a full-physics coupled ocean–atmosphere model is executed. The model is an updated and improved version of the coupled model studied by Latif and Barnett. Evidence is sought for ...

Niklas Schneider; Arthur J. Miller; David W. Pierce

2002-03-01T23:59:59.000Z

94

Galactic Variable Sky with EGRET and GLAST  

Science Conference Proceedings (OSTI)

The characteristics of the largely-unidentified Galactic sources of gamma rays that were detected by EGRET are reviewed. Proposed source populations that may have the correct spatial, spectral, luminosity, and variability properties to be the origins of the EGRET sources are also presented. Finally, the prospects for studying Galactic gamma-ray sources with the GLAST LAT are reviewed.

Digel, S.W.; /SLAC

2006-11-28T23:59:59.000Z

95

A strain gage?variable area flowmeter  

Science Conference Proceedings (OSTI)

This article presents a unique hybrid flowmeter that combines the turndown ratio/low resistance benefits of a variable area differential pressure flowmeter with the low component simplicity of a target flowmeter. The design attaches a single element strain gage to the flexural membrane suspended in a fluid flow passage

D. W. Guillaume; D. DeVries

1990-01-01T23:59:59.000Z

96

Variation of Area Variables in Regge Calculus  

E-Print Network (OSTI)

We consider the possibility to use the areas of two-simplexes, instead of lengths of edges, as the dynamical variables of Regge calculus. We show that if the action of Regge calculus is varied with respect to the areas of two-simplexes, and appropriate constraints are imposed between the variations, the Einstein-Regge equations are recovered.

Jarmo Makela

1998-01-09T23:59:59.000Z

97

10 X-rays from Cataclysmic Variables  

E-Print Network (OSTI)

Cataclysmic Variables ? (CVs) are a distinct class of interacting binaries, transferring mass from a donor star to a degenerate accretor, a white dwarf (WD). In all observational determinations, and as is required by theory for stable mass transfer, the donor star is of lower mass than the accretor.

Erik Kuulkers; Andrew Norton; Axel Schwope; Brian Warner

2003-01-01T23:59:59.000Z

98

Investigation of determinism in heart rate variability  

Science Conference Proceedings (OSTI)

The article searches for the possible presence of determinism in heart rate variability (HRV) signals by using a new approach based on NARMA (nonlinear autoregressive moving average) modeling and free-run prediction. Thirty-three 256-point HRV time series obtained from Wistar rats submitted to different autonomic blockade protocols are considered

M. E. D. Gomes; A. V. P. Souza; H. N. Guimarăes; L. A. Aguirre

2000-01-01T23:59:59.000Z

99

CHARACTERIZING THE OPTICAL VARIABILITY OF BRIGHT BLAZARS: VARIABILITY-BASED SELECTION OF FERMI ACTIVE GALACTIC NUCLEI  

SciTech Connect

We investigate the use of optical photometric variability to select and identify blazars in large-scale time-domain surveys, in part to aid in the identification of blazar counterparts to the {approx}30% of {gamma}-ray sources in the Fermi 2FGL catalog still lacking reliable associations. Using data from the optical LINEAR asteroid survey, we characterize the optical variability of blazars by fitting a damped random walk model to individual light curves with two main model parameters, the characteristic timescales of variability {tau}, and driving amplitudes on short timescales {sigma}-circumflex. Imposing cuts on minimum {tau} and {sigma}-circumflex allows for blazar selection with high efficiency E and completeness C. To test the efficacy of this approach, we apply this method to optically variable LINEAR objects that fall within the several-arcminute error ellipses of {gamma}-ray sources in the Fermi 2FGL catalog. Despite the extreme stellar contamination at the shallow depth of the LINEAR survey, we are able to recover previously associated optical counterparts to Fermi active galactic nuclei with E {>=} 88% and C = 88% in Fermi 95% confidence error ellipses having semimajor axis r < 8'. We find that the suggested radio counterpart to Fermi source 2FGL J1649.6+5238 has optical variability consistent with other {gamma}-ray blazars and is likely to be the {gamma}-ray source. Our results suggest that the variability of the non-thermal jet emission in blazars is stochastic in nature, with unique variability properties due to the effects of relativistic beaming. After correcting for beaming, we estimate that the characteristic timescale of blazar variability is {approx}3 years in the rest frame of the jet, in contrast with the {approx}320 day disk flux timescale observed in quasars. The variability-based selection method presented will be useful for blazar identification in time-domain optical surveys and is also a probe of jet physics.

Ruan, John J.; Anderson, Scott F.; MacLeod, Chelsea L.; Becker, Andrew C.; Davenport, James R. A.; Ivezic, Zeljko [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Burnett, T. H. [Department of Physics, University of Washington, Seattle, WA 98195-1560 (United States); Kochanek, Christopher S. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Plotkin, Richard M. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Sesar, Branimir [Division of Physics, Mathematics and Astronomy, Caltech, Pasadena, CA 91125 (United States); Stuart, J. Scott, E-mail: jruan@astro.washington.edu [Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02420-9108 (United States)

2012-11-20T23:59:59.000Z

100

A Bayesian decision theory approach to variable selection for discrimination  

Science Conference Proceedings (OSTI)

Motivated by examples in spectroscopy, we study variable selection for discrimination in problems with very many predictor variables. Assuming multivariate normal distributions with common variance for the predictor variables within groups, we develop ... Keywords: Bayes, decision theory, discriminant analysis, near infrared spectroscopy, simulated annealing, variable selection

T. Fearn; P. J. Brown; P. Besbeas

2002-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Variable selection and ranking for analyzing automobile traffic accident data  

Science Conference Proceedings (OSTI)

Variable ranking and feature selection are important concepts in data mining and machine learning. This paper introduces a new variable ranking technique named Sum Max Gain Ratio (SMGR). The new technique is evaluated within the domain of traffic accident ... Keywords: decision tree, traffic accident data, variable and feature selection, variable ranking

Huanjing Wang; Allen Parrish; Randy K. Smith; Susan Vrbsky

2005-03-01T23:59:59.000Z

102

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 â—Ź 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.

103

Thermodynamics in variable speed of light theories  

SciTech Connect

The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light (c), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of c is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

Racker, Juan [CONICET, Centro Atomico Bariloche, Avenida Bustillo 9500 (8400), San Carlos De Bariloche (Argentina); Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina); Sisterna, Pablo [Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350 (7600), Mar del Plata (Argentina); Vucetich, Hector [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina)

2009-10-15T23:59:59.000Z

104

Discrete variable theory of triatomic photodissociation  

SciTech Connect

The coupled equations describing the photodissociation process are expressed in the discrete variable representation (DVR) in which the coupled equations are labeled by quadrature points rather than by internal basis functions. A large reduction in the dimensionality of the coupled equations can be realized since the spatially localized bound state nuclear wave function vanishes at most of the quadrature points, making only certain orientations of the fragments important in the region of strong interaction (small separation). The discrete variable theory of photodissociation is applied to the model dissociation of bent HCN in which the CN fragment is treated as a rigid rotor. The truncated DVR rotational distributions are compared with the exact close coupled rotational distributions, and excellent agreement with greatly reduced dimensionality of the equations is found.

Heather, R.W.; Light, J.C.

1983-07-01T23:59:59.000Z

105

Solar energy: some variables influencing increased utilization  

SciTech Connect

The mid 1970s energy crisis encouraged the growth of alternative fuels. Through the late 1970s and 1980s, solar energy was the primary alternative fuel. Federal and state programs encouraged the growth of residential solar installations through the use of tax credits. This dissertation used data from the eleven western states to assess tax credits' influence on residential solar installations. A Spearman's r was used to evaluate the role of tax credits on the percent increase in solar systems from 1980 to 1984. The r/sub s/ was .93. The second portion of the analysis used contingency tables to see if variables other than tax credits influence solar installations; the results showed tax credits + solar radiation and fuel mix are the significant variables. The final chapter looks at municipal solar utilities, tax on excessive energy use, a public/private solar research lab, and building rating system as means to supplement solar energy tax credits.

Born, B.E.

1986-01-01T23:59:59.000Z

106

Thermodynamics in variable speed of light theories  

E-Print Network (OSTI)

The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light ($c$), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of $c$ is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

Juan Racker; Pablo Sisterna; Hector Vucetich

2007-11-06T23:59:59.000Z

107

Review of Variable Generation Integration Charges  

DOE Green Energy (OSTI)

The growth of wind and solar generation in the United States, and the expectation of continued growth of these technologies, dictates that the future power system will be operated in a somewhat different manner because of increased variability and uncertainty. A small number of balancing authorities have attempted to determine an 'integration cost' to account for these changes to their current operating practices. Some balancing authorities directly charge wind and solar generators for integration charges, whereas others add integration charges to projected costs of wind and solar in integrated resource plans or in competitive solicitations for generation. This report reviews the balancing authorities that have calculated variable generation integration charges and broadly compares and contrasts the methodologies they used to determine their specific integration charges. The report also profiles each balancing authority and how they derived wind and solar integration charges.

Porter, K.; Fink, S.; Buckley, M.; Rogers, J.; Hodge, B. M.

2013-03-01T23:59:59.000Z

108

CVcat: an interactive database on cataclysmic variables  

E-Print Network (OSTI)

CVcat is a database that contains published data on cataclysmic variables and related objects. Unlike in the existing online sources, the users are allowed to add data to the catalogue. The concept of an ``open catalogue'' approach is reviewed together with the experience from one year of public usage of CVcat. New concepts to be included in the upcoming AstroCat framework and the next CVcat implementation are presented. CVcat can be found at http://www.cvcat.org.

J. Kube; B. T. Gaensicke; F. Euchner; B. Hoffmann

2003-04-29T23:59:59.000Z

109

Bessel-Zernike Discrete Variable Representation Basis  

SciTech Connect

The connection between the Bessel discrete variable basis expansion and a specific form of an orthogonal set of Jacobi polynomials is demonstrated. These so-called Zernike polynomials provide alternative series expansions of suitable functions over the unit interval. Expressing a Bessel function in a Zernike expansion provides a straightforward method of generating series identities. Furthermore, the Zernike polynomials may also be used to efficiently evaluate the Hankel transform for rapidly decaying functions or functions with finite support.

Cerjan, C J

2005-10-24T23:59:59.000Z

110

Mobile Variable Depth Sampling System Design Study  

Science Conference Proceedings (OSTI)

A design study is presented for a mobile, variable depth sampling system (MVDSS) that will support the treatment and immobilization of Hanford LAW and HLW. The sampler can be deployed in a 4-inch tank riser and has a design that is based on requirements identified in the Level 2 Specification (latest revision). The waste feed sequence for the MVDSS is based on Phase 1, Case 3S6 waste feed sequence. Technical information is also presented that supports the design study.

BOGER, R.M.

2000-08-25T23:59:59.000Z

111

Variability of PV on Distribution Systems  

Science Conference Proceedings (OSTI)

In 2010, the Electric Power Research Institute (EPRI) along with several utilities began collecting high-resolution monitoring data on distributed solar photovoltaic (PV) systems throughout the United States. Included in these monitoring data are single-module PV systems distributed along selected feeders as well as several larger PV systems (up to 1.4 MW). Utilizing data from these sites, this report focuses specifically on examining the measured variability of solar PV distributed throughout a ...

2012-12-13T23:59:59.000Z

112

Changes in heart rate variability during fainting  

Science Conference Proceedings (OSTI)

Studies of heart rate variability in people who faint may yield insights into normal physiologic mechanisms which probably are dynamic. These insights might be gained because fainting appears to be due to a breakdown of these mechanisms. Tilt table testing reliably induces fainting in patients with a history of fainting and can be used to study these mechanisms. During tilt tests ending in fainting heart rate changes markedly

Robert Sheldon; Kenneth Riff

1991-01-01T23:59:59.000Z

113

Climatic variability within an equilibrium greenhouse simulation  

SciTech Connect

A simulation of the possible consequences of a doubling of the CO{sub 2} content of the atmosphere has been performed with a low resolution global climatic model. The model included the diurnal and seasonal computed sea ice amount and cloud cover, and used implied oceanic heat fluxes to represent transport processes in the oceans. A highly responsive 2-layer soil moisture formulation was also incorporated. Twenty year equilibrated simulations for control (1xCO{sub 2}) and greenhouse (2xCO{sub 2}) conditions were generated. The major emphasis of the analysis presented here is on the intra-annual and interannual variability of the greenhouse run with respect to the control run. This revealed considerable differences from the time-averaged results with occasions of marked positive and negative temperature deviations. Of particular interest were the periods of negative temperature departures compared to the control run which were identified, especially over the Northern Hemisphere continents. Temporal and spatial precipitation and soil moisture anomalies also occurred, some of which were related to the surface temperature changes. Substantial sea surface temperature anomalies were apparent in the greenhouse run, indicating that a source of climatic forcing existed in addition to that due to doubling of the CO{sub 2}. Comparison of the intra-annual and interannual variability of the control run with that of the greenhouse run suggests that, in many situations, it will be difficult to identify a greenhouse signal against the intrinsic natural variability of the climatic system. 35 refs., 20 figs., 1 tab.

Gordon, H.B.; Hunt, B.G. [CSIRO Division of Atmospheric Research, Victoria (Austria)

1994-01-01T23:59:59.000Z

114

Allocating Variability and Reserve Requirements (Presentation)  

SciTech Connect

This presentation describes how you could conceivably allocate variability and reserve requirements, including how to allocate aggregation benefits. Conclusions of this presentation are: (1) Aggregation provides benefits because individual requirements are not 100% correlated; (2) Method needed to allocate reduced requirement among participants; (3) Differences between allocation results are subtle - (a) Not immediately obvious which method is 'better'; (b) Many are numerically 'correct', they sum to the physical requirement; (c) Many are not 'fair', Results depend on sub-aggregation and/or the order individuals are included; and (4) Vector allocation method is simple and fair.

Kirby, B.; King, J.; Milligan, M.

2011-10-01T23:59:59.000Z

115

Long-Term Wind Power Variability  

DOE Green Energy (OSTI)

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

Wan, Y. H.

2012-01-01T23:59:59.000Z

116

Allocating Variability and Reserve Requirements (Presentation)  

DOE Green Energy (OSTI)

This presentation describes how you could conceivably allocate variability and reserve requirements, including how to allocate aggregation benefits. Conclusions of this presentation are: (1) Aggregation provides benefits because individual requirements are not 100% correlated; (2) Method needed to allocate reduced requirement among participants; (3) Differences between allocation results are subtle - (a) Not immediately obvious which method is 'better'; (b) Many are numerically 'correct', they sum to the physical requirement; (c) Many are not 'fair', Results depend on sub-aggregation and/or the order individuals are included; and (4) Vector allocation method is simple and fair.

Kirby, B.; King, J.; Milligan, M.

2011-10-01T23:59:59.000Z

117

Constraints on Area Variables in Regge Calculus  

E-Print Network (OSTI)

We describe a general method of obtaining the constraints between area variables in one approach to area Regge calculus, and illustrate it with a simple example. The simplicial complex is the simplest tessellation of the 4-sphere. The number of independent constraints on the variations of the triangle areas is shown to equal the difference between the numbers of triangles and edges, and a general method of choosing independent constraints is described. The constraints chosen by using our method are shown to imply the Regge equations of motion in our example.

Jarmo Makela; Ruth M. Williams

2000-11-02T23:59:59.000Z

118

Constraints on Area Variables in Regge Calculus  

E-Print Network (OSTI)

We describe a general method of obtaining the constraints between area variables in one approach to area Regge calculus, and illustrate it with a simple example. The simplicial complex is the simplest tessellation of the 4-sphere. The number of independent constraints on the variations of the triangle areas is shown to equal the difference between the numbers of triangles and edges, and a general method of choosing independent constraints is described. The constraints chosen by using our method are shown to imply the Regge equations of motion in our example.

Mäkelä, J M; Makela, Jarmo; Williams, Ruth M.

2001-01-01T23:59:59.000Z

119

Empowering Variable Renewables: Options for Flexible Electricity Systems |  

Open Energy Info (EERE)

Empowering Variable Renewables: Options for Flexible Electricity Systems Empowering Variable Renewables: Options for Flexible Electricity Systems Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Empowering Variable Renewables: Options for Flexible Electricity Systems Agency/Company /Organization: International Energy Agency Sector: Energy Focus Area: Renewable Energy Topics: Market analysis, Technology characterizations Resource Type: Publications Website: www.iea.org/g8/2008/Empowering_Variable_Renewables.pdf Empowering Variable Renewables: Options for Flexible Electricity Systems Screenshot References: Empowering Variable Renewables: Options for Flexible Electricity Systems[1] Summary "Increasing the share of renewables in energy portfolios is a key tool in the drive to reduce anthropogenic carbon dioxide emissions, as well as

120

Variably insulating portable heater/cooler  

DOE Patents (OSTI)

A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

Potter, T.F.

1998-09-29T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

IS ACTIVE REGION CORE VARIABILITY AGE DEPENDENT?  

Science Conference Proceedings (OSTI)

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

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

2012-12-10T23:59:59.000Z

122

Variable temperature seat climate control system  

DOE Patents (OSTI)

A temperature climate control system comprises a variable temperature seat, at least one heat pump, at least one heat pump temperature sensor, and a controller. Each heat pump comprises a number of Peltier thermoelectric modules for temperature conditioning the air in a main heat exchanger and a main exchanger fan for passing the conditioned air from the main exchanger to the variable temperature seat. The Peltier modules and each main fan may be manually adjusted via a control switch or a control signal. Additionally, the temperature climate control system may comprise a number of additional temperature sensors to monitor the temperature of the ambient air surrounding the occupant as well as the temperature of the conditioned air directed to the occupant. The controller is configured to automatically regulate the operation of the Peltier modules and/or each main fan according to a temperature climate control logic designed both to maximize occupant comfort during normal operation, and minimize possible equipment damage, occupant discomfort, or occupant injury in the event of a heat pump malfunction.

Karunasiri, Tissa R. (Van Nuys, CA); Gallup, David F. (Pasadena, CA); Noles, David R. (Glendale, CA); Gregory, Christian T. (Alhambra, CA)

1997-05-06T23:59:59.000Z

123

Variably insulating portable heater/cooler  

DOE Green Energy (OSTI)

A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

Potter, Thomas F. (Denver, CO)

1998-01-01T23:59:59.000Z

124

SLUDGE BATCH VARIABILITY STUDY WITH FRIT 418  

SciTech Connect

The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO{sub 2} resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass regardless of thermal history. All of the normalized boron releases were less than 1 g/L. While all of the targeted glass compositions were predictable with respect to the Product Composition Control System (PCCS) models for durability, a small number of the measured glass compositions were located outside of the lower prediction limit indicating poorer durability than what was actually measured. These unpredictable glasses were in the same lithium metaborate (LM) preparation block during the chemical analyses, which resulted in measured compositions that were not representative of the target compositions. A review of the data did not indicate a clear cause for the problem. Re-digestion and re-measurement of three glasses from this preparation block yielded glass compositions closer to the target values and predicted PCT responses within the PCCS model uncertainty. Therefore, it is believed that the glasses were correctly fabricated and the targeted compositions are closer representations of the true compositions. Per the requirements of the DWPF Glass Product Control Program, the PCCS durability models have been shown to be applicable for the SB6/Frit 418 glass system. PCT results from the glasses fabricated as part of the variability study were shown to be predictable and/or acceptable with respect to the DWPF PCCS models. In addition, the inclusion of ThO{sub 2} was shown to have minimal impact on the acceptability and predictability of the variability study glasses.

Johnson, F.; Edwards, T.

2010-11-29T23:59:59.000Z

125

Variable Speed Drive Volumetric Tracking (VSDVT) for Airflow Control in Variable Air Volume (VAV) Systems  

E-Print Network (OSTI)

An airflow control method has been developed for variable air volume (VAV) systems. This airflow control method is named VSD volumetric tracking (VSDVT) since both the supply and return airflows are determined using signals of the variable speed drives (VSD) instead of the flow stations. Its performance is studied and compared with the fan tracking (FT) method using model simulations. The VSDVT maintains a constant building pressure and the required outside airflow under all load conditions, reduces the annual return air fan energy by up to 50%, and the annual supply air fan energy by up to 30%. This paper presents the VSDVT method, the system models, and the simulation results.

Liu, M.

2002-01-01T23:59:59.000Z

126

Variability of the Somali Current as Observed from Seasat Altimetry  

Science Conference Proceedings (OSTI)

Three methods of extraction of mesoscale variability from altimetry are compared in the Somali current area: crossover residuals after minimization to reduce orbit errors, along-track variability using quasi-repetitive tracks, and difference ...

C. Perigaud; J. F. Minster

1988-01-01T23:59:59.000Z

127

U-090: RSA enVision Discloses Environment Variable Information...  

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

0: RSA enVision Discloses Environment Variable Information to Remote Users U-090: RSA enVision Discloses Environment Variable Information to Remote Users January 27, 2012 - 6:00am...

128

Stochastic Forcing of Ocean Variability by the North Atlantic Oscillation  

Science Conference Proceedings (OSTI)

At middle and high latitudes, the magnitude of stochastic wind stress forcing of the ocean by atmospheric variability on synoptic time scales (i.e., “weather” related variability) is comparable to that of the seasonal cycle. Stochastic forcing ...

Kettyah C. Chhak; Andrew M. Moore; Ralph F. Milliff

2009-01-01T23:59:59.000Z

129

Spatial Variability of Shortwave Irradiance for Snowmelt in Forests  

Science Conference Proceedings (OSTI)

The spatial variation of melt energy can influence snow cover depletion rates and in turn be influenced by the spatial variability of shortwave irradiance to snow. The spatial variability of shortwave irradiance during melt under uniform and ...

John Pomeroy; Chad Ellis; Aled Rowlands; Richard Essery; Janet Hardy; Tim Link; Danny Marks; Jean Emmanuel Sicart

2008-12-01T23:59:59.000Z

130

West African Monsoon Intraseasonal Variability: A Precipitable Water Perspective  

Science Conference Proceedings (OSTI)

West African monsoon intraseasonal variability has important implications for food security and drought early warnings. In the present study, intraseasonal variability over the Sahel is assessed from the perspective of precipitable water, as ...

D. Emmanuel Poan; Romain Roehrig; Fleur Couvreux; Jean-Philippe Lafore

2013-04-01T23:59:59.000Z

131

Temporal Variability of Diapycnal Mixing in Shag Rocks Passage  

Science Conference Proceedings (OSTI)

Diapycnal mixing rates in the oceans have been shown to have a great deal of spatial variability, but the temporal variability has been little studied. Here results are presented from a method developed to calculate diapycnal diffusivity from ...

Gillian M. Damerell; Karen J. Heywood; David P. Stevens; Alberto C. Naveira Garabato

2012-03-01T23:59:59.000Z

132

Modeling the Variability of Sydney Harbor Wind Measurements  

Science Conference Proceedings (OSTI)

The time-dependent behavior in the variability of wind measurements is investigated using bivariate generalized autoregressive conditional heteroscedastic models. These models express the current level of short-timescale wind variability in terms ...

Edward Cripps; William T. M. Dunsmuir

2003-08-01T23:59:59.000Z

133

LPB Hydro-Climate Variability as Simulated by GCM Experiments...  

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

LPB Hydro-Climate Variability as Simulated by GCM Experiments: Role of Remote SST Forcing Title LPB Hydro-Climate Variability as Simulated by GCM Experiments: Role of Remote SST...

134

Snowpack spatial variability: towards understanding its effect on remote sensing  

E-Print Network (OSTI)

Snowpack spatial variability: towards understanding its effect on remote sensing measurements spatial variability: towards understanding its effect on remote sensing mea- surements and snow slope large errors in these basin estimates. Remote sensing measurements offer a promising alternative, due

Marshall, Hans-Peter

135

Jet Jumping: Low-Frequency Variability in the Southern Ocean  

Science Conference Proceedings (OSTI)

The authors study intrinsic variability in the position of jets in a ?-plane channel ocean with simple topography using a quasigeostrophic numerical model. This study links the variability in jet position with abyssal anticyclones that form as a ...

Christopher C. Chapman; Andrew McC. Hogg

2013-05-01T23:59:59.000Z

136

Modeling Climate Variability in the Tropical Atlantic Atmosphere  

Science Conference Proceedings (OSTI)

Climate variability in the tropical Atlantic sector as represented in six atmospheric general circulation models is examined. On the annual mean, most simulations overestimate wind stress away from the equator although much of the variability can ...

Jiande Wang; James A. Carton

2003-12-01T23:59:59.000Z

137

Intraseasonal Variability over Tropical Africa during Northern Summer  

Science Conference Proceedings (OSTI)

The intraseasonal variability over Africa during northern summer was analyzed, using 25 years of NCEP– NCAR reanalysis and satellite data. The dominant pattern of variability was one of enhanced deep convection over the whole African monsoon ...

Adrian J. Matthews

2004-06-01T23:59:59.000Z

138

Tropical Cloud Feedbacks and Natural Variability of Climate  

Science Conference Proceedings (OSTI)

Simulations of natural variability by two GCMs are examined. One GCM is a sector model, allowing relatively rapid integration without simplification of the model physics, which would potentially exclude mechanisms of variability. Two mechanisms ...

R. L. Miller; A. D. Del Genio

1994-09-01T23:59:59.000Z

139

A search for chaotic behavior in Northern Hemisphere stratospheric variability  

Science Conference Proceedings (OSTI)

Northern Hemisphere stratospheric variability is investigated with respect to chaotic behavior using time series from three different variables extracted from four different re-analysis products and two numerical model runs with different forcing. ...

Gualtiero Badin; Daniela I.V. Domeisen

140

Role of Smarter Grids in Variable Renewable Resource Integration (Presentation)  

Science Conference Proceedings (OSTI)

This presentation discusses the role of smarter grids in variable renewable resource integration and references material from a forthcoming ISGAN issue paper: Smart Grid Contributions to Variable Renewable Resource Integration, co-written by the presenter and currently in review.

Miller, M.

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Holographic Dark Energy Scenario and Variable Modified Chaplygin Gas  

E-Print Network (OSTI)

In this letter, we have considered that the universe is filled with normal matter and variable modified Chaplygin gas. Also we have considered the interaction between normal matter and variable modified Chaplygin gas in FRW universe. Then we have considered a correspondence between the holographic dark energy density and interacting variable modified Chaplygin gas energy density. Then we have reconstructed the potential of the scalar field which describes the variable modified Chaplygin cosmology.

Surajit Chattopadhyay; Ujjal Debnath

2009-01-15T23:59:59.000Z

142

Bayesian Variable Selection and the Swendsen-Wang Algorithm  

E-Print Network (OSTI)

Bayesian Variable Selection and the Swendsen-Wang Algorithm David J. NOTT and Peter J. GREEN improvements in Markov chain Monte Carlo sampling algorithms for Bayesian variable selection. Currently used, this excludes the ith predictor from the model. The problem of variable selection is to decide which predictors

Green, Peter

143

Bayesian variable selection and the Swendsen-Wang algorithm  

E-Print Network (OSTI)

Bayesian variable selection and the Swendsen-Wang algorithm David J. Nott1 and Peter J. Green2 1 motivated improvements in Markov chain Monte Carlo sampling algorithms for Bayesian variable selection. Traditional sampling al- gorithms for Bayesian variable selection may perform poorly when there are severe

Barber, Stuart

144

Quantifying decoherence in continuous variable systems  

E-Print Network (OSTI)

We present a detailed report on the decoherence of quantum states of continuous variable systems under the action of a quantum optical master equation resulting from the interaction with general Gaussian uncorrelated environments. The rate of decoherence is quantified by relating it to the decay rates of various, complementary measures of the quantum nature of a state, such as the purity, some nonclassicality indicators in phase space and, for two-mode states, entanglement measures and total correlations between the modes. Different sets of physically relevant initial configurations are considered, including one- and two-mode Gaussian states, number states, and coherent superpositions. Our analysis shows that, generally, the use of initially squeezed configurations does not help to preserve the coherence of Gaussian states, whereas it can be effective in protecting coherent superpositions of both number states and Gaussian wave packets. 1

A. Serafini; M. G. A. Paris; F. Illuminati; S. De Siena

2005-01-01T23:59:59.000Z

145

Variational estimates using a discrete variable representation  

SciTech Connect

The advantage of using a discrete variable representation (DVR) is that the Hamiltonian of two interacting particles can be constructed in a very simple form. However, the DVR Hamiltonian is approximate and, as a consequence, the results cannot be considered as variational ones. We will show that the variational character of the results can be restored by performing a reduced number of integrals. In practice, for a variational description of the lowest n bound states only n(n+1)/2 integrals are necessary whereas D(D+1)/2 integrals are enough for the scattering states (D is the dimension of the S matrix). Applications of the method to the study of dimers of He, Ne and Ar, for both bound and scattering states, are presented.

Lombardi, M.; Barletta, P.; Kievsky, A. [Istituto Nazionale di Fisica Nucleare, Via Buonarroti 2, 56100 Pisa (Italy); Dipartimento di Fisica, Universita di Pisa, 56100 Pisa (Italy)

2004-09-01T23:59:59.000Z

146

Variable selection in nonparametric additive models  

E-Print Network (OSTI)

We consider a nonparametric additive model of a conditional mean function in which the number of variables and additive components may be larger than the sample size but the number of nonzero additive components is "small" relative to the sample size. The statistical problem is to determine which additive components are nonzero. The additive components are approximated by truncated series expansions with B-spline bases. With this approximation, the problem of component selection becomes that of selecting the groups of coefficients in the expansion. We apply the adaptive group Lasso to select nonzero components, using the group Lasso to obtain an initial estimator and reduce the dimension of the problem. We give conditions under which the group Lasso selects a model whose number of components is comparable with the underlying model, and the adaptive group Lasso selects the nonzero components correctly with probability approaching one as the sample size increases and achieves the optimal rate of convergence. Th...

Huang, Jian; Wei, Fengrong; 10.1214/09-AOS781

2010-01-01T23:59:59.000Z

147

Forecasting neutron star temperatures: predictability and variability  

E-Print Network (OSTI)

It is now possible to model thermal relaxation of neutron stars after bouts of accretion during which the star is heated out of equilibrium by nuclear reactions in its crust. Major uncertainties in these models can be encapsulated in modest variations of a handful of fudge parameters that change the crustal thermal conductivity, specific heat, and heating rates. Observations of thermal relaxation constrain these fudge parameters and allow us to predict longer term variability in terms of the neutron star core temperature. We demonstrate this explicitly by modeling ongoing thermal relaxation in the neutron star XTE J1701-462. Its future cooling, over the next 5 to 30 years, is strongly constrained and depends mostly on its core temperature, uncertainties in crust physics having essentially been pinned down by fitting to the first three years of observations.

Dany Page; Sanjay Reddy

2013-07-17T23:59:59.000Z

148

Variable Interactions in Query-Driven Visualization  

SciTech Connect

One fundamental element of scientific inquiry is discoveringrelationships, particularly the interactions between different variablesin observed or simulated phenomena. Building upon our prior work in thefield of Query-Driven Visualization, where visual data analysisprocessing is focused on subsets of large data deemed to be"scientifically interesting," this new work focuses on a novel knowledgediscovery capability suitable for use with petascale class datasets. Itenables visual presentation of the presence or absence of relationships(correlations) between variables in data subsets produced by Query-Drivenmethodologies. This technique holds great potential for enablingknowledge discovery from large and complex datasets currently emergingfrom SciDAC and INCITE projects. It is sufficiently generally to beapplicable to any time of complex, time-varying, multivariate data fromstructured, unstructured or adaptive grids.

Bethel, E. Wes; Gosink, Luke J.; Anderson, John C.; Joy, Kenneth I.

2007-10-25T23:59:59.000Z

149

Quantifying decoherence in continuous variable systems  

E-Print Network (OSTI)

We present a detailed report on the decoherence of quantum states of continuous variable systems under the action of a quantum optical master equation resulting from the interaction with general Gaussian uncorrelated environments. The rate of decoherence is quantified by relating it to the decay rates of various, complementary measures of the quantum nature of a state, such as the purity, some nonclassicality indicators in phase space and, for two-mode states, entanglement measures and total correlations between the modes. Different sets of physically relevant initial configurations are considered, including one- and two-mode Gaussian states, number states, and coherent superpositions. Our analysis shows that, generally, the use of initially squeezed configurations does not help to preserve the coherence of Gaussian states, whereas it can be effective in protecting coherent superpositions of both number states and Gaussian wave packets.

A. Serafini; M. G. A. Paris; F. Illuminati; S. De Siena

2005-01-28T23:59:59.000Z

150

The TAOS Project Stellar Variability II. Detection of 15 Variable Stars  

SciTech Connect

The Taiwanese-American Occultation Survey (TAOS) project has collected more than a billion photometric measurements since 2005 January. These sky survey data - covering timescales from a fraction of a second to a few hundred days - are a useful source to study stellar variability. A total of 167 star fields, mostly along the ecliptic plane, have been selected for photometric monitoring with the TAOS telescopes. This paper presents our initial analysis of a search for periodic variable stars from the time-series TAOS data on one particular TAOS field, No. 151 (RA = 17{sup h} 30{sup m} 6.67{sup s}, Dec = 27 degrees, 17 minutes, 30 seconds, J2000), which had been observed over 47 epochs in 2005. A total of 81 candidate variables are identified in the 3 square degree field, with magnitudes in the range 8 < R < 16. On the basis of the periodicity and shape of the lightcurves, 32 variables, 18 of which were previously unknown, are classified as RR Lyrae, Cepheid, {delta} Scuti, SX Phonencis, semi-regular and eclipsing binaries.

Mondal, S; Lin, C C; Zhang, Z W; Alcock, C; Axelrod, T; Bianco, F B; Byun, Y I; Coehlo, N K; Cook, K H; Dave, R; Kim, D W; King, S K; Lee, T; Lehner, M J; Lin, H C; Marshall, S L; Protopapas, P; Rice, J A; Schwamb, M E; Wang, J H; Wang, S Y; Wen, C Y

2010-01-28T23:59:59.000Z

151

Stochastic variability of effective properties via the generalized variability response function  

Science Conference Proceedings (OSTI)

Homogenization of randomly heterogeneous material properties into effective properties is an essential procedure in facilitating the analysis of a wide range of mechanics problems. Although formulas exist to calculate deterministic effective properties ... Keywords: Effective properties, Random fields, Uncertainty quantification, Variability response functions

Kirubel Teferra; Sanjay R. Arwade; George Deodatis

2012-11-01T23:59:59.000Z

152

Characterisation of soil texture variability using the apparent soil electrical conductivity at a highly variable site  

Science Conference Proceedings (OSTI)

The characterisation of the spatial distribution of clay, silt, and sand/gravel is one of the main objectives of soil surveys. Researchers as well as producers have an interest in characterising soil texture variability. The objective of our study was ... Keywords: Clay, EM38, Residual kriging, Sand/gravel, Silt, Spatial heterogeneity

K. Heil; U. Schmidhalter

2012-02-01T23:59:59.000Z

153

Continuous variable tangle, monogamy inequality, and entanglement sharing in Gaussian states of continuous variable systems  

E-Print Network (OSTI)

For continuous-variable systems, we introduce a measure of entanglement, the continuous variable tangle ({\\em contangle}), with the purpose of quantifying the distributed (shared) entanglement in multimode, multipartite Gaussian states. This is achieved by a proper convex roof extension of the squared logarithmic negativity. We prove that the contangle satisfies the Coffman-Kundu-Wootters monogamy inequality in all three--mode Gaussian states, and in all fully symmetric $N$--mode Gaussian states, for arbitrary $N$. For three--mode pure states we prove that the residual entanglement is a genuine tripartite entanglement monotone under Gaussian local operations and classical communication. We show that pure, symmetric three--mode Gaussian states allow a promiscuous entanglement sharing, having both maximum tripartite residual entanglement and maximum couplewise entanglement between any pair of modes. These states are thus simultaneous continuous-variable analogs of both the GHZ and the $W$ states of three qubits: in continuous-variable systems monogamy does not prevent promiscuity, and the inequivalence between different classes of maximally entangled states, holding for systems of three or more qubits, is removed.

Gerardo Adesso; Fabrizio Illuminati

2004-10-06T23:59:59.000Z

154

Variable Stars in the Globular Cluster NGC 4590 (M68  

E-Print Network (OSTI)

We present results of time series photometry to search for variable stars in the field of metal-poor globular cluster NGC 4590 (M68). Periods have been revised for 40 known variables and no significant changes were found. A considerable change in Blazhko effect for V25 has been detected. Among nine newly discovered variable candidates, 5 stars are of RRc Bailey type variables while 4 stars are unclassified. The variable stars V10, V21, V50 and V51 are found to be cluster members based on the radial velocity data taken from literature.

Sariya, Devesh Path; Yadav, R K S

2013-01-01T23:59:59.000Z

155

Building Technologies Office: Advanced, Variable Speed Air-Source  

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

Advanced, Variable Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project to someone by E-mail Share Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Facebook Tweet about Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Twitter Bookmark Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Google Bookmark Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Delicious Rank Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Digg Find More places to share Building Technologies Office: Advanced,

156

Fast Selection of Spectral Variables with B-Spline Compression  

E-Print Network (OSTI)

The large number of spectral variables in most data sets encountered in spectral chemometrics often renders the prediction of a dependent variable uneasy. The number of variables hopefully can be reduced, by using either projection techniques or selection methods; the latter allow for the interpretation of the selected variables. Since the optimal approach of testing all possible subsets of variables with the prediction model is intractable, an incremental selection approach using a nonparametric statistics is a good option, as it avoids the computationally intensive use of the model itself. It has two drawbacks however: the number of groups of variables to test is still huge, and colinearities can make the results unstable. To overcome these limitations, this paper presents a method to select groups of spectral variables. It consists in a forward-backward procedure applied to the coefficients of a B-Spline representation of the spectra. The criterion used in the forward-backward procedure is the mutual infor...

Rossi, Fabrice; Wertz, Vincent; Meurens, Marc; Verleysen, Michel

2007-01-01T23:59:59.000Z

157

SLUDGE BATCH 7B GLASS VARIABILITY STUDY  

SciTech Connect

The Defense Waste Processing Facility (DWPF) is preparing to initiate processing Sludge Batch 7b (SB7b). In support of the upcoming processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frits 418 with a 6% Na{sub 2}O addition (26 wt% Na{sub 2}O in sludge) and 702 with a 4% Na{sub 2}O addition (24 wt% Na{sub 2}O in sludge) to process SB7b. This recommendation was based on assessments of the compositional projections for SB7b available at the time from the Savannah River Remediation (SRR). To support qualification of SB7b, SRNL executed a variability study to assess the applicability of the current durability models for SB7b. The durability models were assessed over the expected composition range of SB7b, including potential caustic additions, combined with Frits 702 and 418 over a 32-40% waste loading (WL) range. Thirty four glasses were selected based on Frits 418 and 702 coupled with the sludge projections with an additional 4-6% Na{sub 2}O to reflect the potential caustic addition. Six of these glasses, based on average nominal sludge compositions including the appropriate caustic addition, were developed for both Frit 418 and Frit 702 at 32, 36 and 40% WL to provide coverage in the center of the anticipated SB7b glass region. All glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). To comply with the DWPF Glass Product Control Program, a total of thirty four glasses were fabricated to assess the applicability of the current DWPF PCCS durability models. Based on the measured PCT response, all of the glasses were acceptable with respect to the Environmental Assessment (EA) benchmark glass regardless of thermal history. The NL[B] values of the SB7b variability study glasses were less than 1.99 g/L as compared to 16.695 g/L for EA. A small number of the D-optimally selected 'outer layer' extreme vertices (EV) glasses were not predictable using the current Product Composition Control System (PCCS) models for durability, but were acceptable compared to the EA glass when tested. These glasses fell outside of the lower 95% confidence band, which demonstrates conservatism in the model. A few of the glasses fell outside of the upper 95% confidence band; however, these particular glasses have normalized release values that were much lower than the values of EA and should be of no practical concern. Per the requirements of the DWPF Glass Product Control Program, the PCCS durability models have been shown to be applicable to the SB7b sludge system with a range of Na{sub 2}O concentrations blended with Frits 418 or 702. PCT results from the glasses fabricated as part of the variability study were shown to be predictable by the current DWPF PCCS models and/or acceptable with respect to the EA benchmark glass regardless of thermal history or compositional view.

Johnson, F.; Edwards, T.

2011-10-25T23:59:59.000Z

158

Device for adapting continuously variable transmissions to infinitely variable transmissions with forward-neutral-reverse capabilities  

DOE Patents (OSTI)

An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.

Wilkes, Donald F. (Albuquerque, NM); Purvis, James W. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM)

1997-01-01T23:59:59.000Z

159

REMARKABLE SPECTRAL VARIABILITY OF PDS 456  

SciTech Connect

We report on the highest to date signal-to-noise ratio X-ray spectrum of the luminous quasar PDS 456, as obtained during two XMM-Newton orbits in 2007 September. The present spectrum is considerably different from several previous X-ray spectra recorded for PDS 456 since 1998. The ultra-high-velocity outflow seen as recently as 2007 February is not detected in absorption. Conversely, a significant reflection component is detected (DELTAchi{sup 2} = 313 compared to a simple absorbed power law). The reflection model suggests that the reflecting medium may be outflowing at a velocity v/c = -0.06 +- 0.02 (DELTAchi{sup 2} = 28 compared to v/c = 0). The present spectrum is analyzed in the context of the previous ones in an attempt to understand all spectra within the framework of a single model. We examine whether an outflow with variable partial covering of the X-ray source along the line of sight that also reflects the source from other lines of sight can explain the dramatic variations in the broadband spectral curvature of PDS 456. It is established that absorption plays a major role in shaping the spectrum of other epochs, while the 2007 XMM-Newton spectrum is dominated by reflection, and the coverage of the source by the putative outflow is small (<20%).

Behar, Ehud; Mushotzky, Richard [Code 662, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kaspi, Shai [Department of Physics, Technion, Haifa 32000 (Israel); Reeves, James [School of Physics and Geographical Sciences, Keele University, Keele, Staffordshire ST5 5BG (United Kingdom); Turner, T. J. [Department of Physics, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States); O'Brien, Paul T. [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom)

2010-03-20T23:59:59.000Z

160

MEXICAN CORN: Genetic Variability and Trade Liberalisation  

E-Print Network (OSTI)

It is now a well established fact that corn (Zea mays) originated in Mexico and that a great part of the evolution that may be observed in terms of this plant’s genetic variability took place in this country. 2 As the plant’s history unfolded, early forms of these races were taken by people into a wide variety of environments and ecological niches from which many distinct varieties developed in the relative isolation of these separated regions. Thus, Mexico also became a center of genetic diversity for corn, and its stock of germplasm has contributed in a decisive manner to global production of corn. Even the dented varieties of the U.S. Corn Belt are close descendants of the first Mexican landraces. The germplasm resources that are deposited in Mexico’s corn varieties, as well as in the wild relatives of this crop, are of prime importance for the world’s food production system of the next century. 3 Corn germplasm of Mexican origin has played a critical role in improvements for corn cultivated in tropical regions in relation to yield increments, plague resistance, short growth cycle, drought resistance and increases of protein content of grain. It has also been instrumental in increasing yields in the case of corn produced in temperate regions at high latitudes. Mexican 1

Alejandro Nadal; El Colegio De México; Alejandro Nadal; El Colegio De México

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Carderock 2-ft Variable Pressure Cavitation Water Tunnel | Open Energy  

Open Energy Info (EERE)

2-ft Variable Pressure Cavitation Water Tunnel 2-ft Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 2-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.6 Depth(m) 0.6 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 2-Foot Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating, variable-speed, variable-pressure, open jet test section, closed jet test section, and semi-rectangular test section. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 17 Recirculating Yes

162

Carderock 3-ft Variable Pressure Cavitation Water Tunnel | Open Energy  

Open Energy Info (EERE)

Variable Pressure Cavitation Water Tunnel Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 3-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.7 Depth(m) 0.7 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 3-ft Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating with resorber, variable-speed, variable-pressure, two interchangeable circular test sections. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 25.8 Recirculating Yes Wind Capabilities Wind Capabilities None

163

NERC Presentation: Accommodating High Levels of Variable Generation,  

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

NERC Presentation: Accommodating High Levels of Variable NERC Presentation: Accommodating High Levels of Variable Generation, October 29, 2010 NERC Presentation: Accommodating High Levels of Variable Generation, October 29, 2010 North American Electric Reliability Corporation (NERC) presentation to the Electricity Advisory Committee, October 29, 2010, on accommodating high levels of variable electricity eneration. Variable resources are types of electric power generation that rely on an uncontrolled, "variable" fuel (e.g. wind, sunlight, waves, tidal forces, and some types of rivers) to generate electricity. Most renewablesfall into this category. Reliably integrating these resources into the bulk power system will require significant changes to traditional methods used for system planning and operation. Ongoing efforts brought together by NERC and its stakeholders

164

Multi-winding Homopolar Electric Machine Offers Variable ...  

The device can be used as either a motor or a generator. Advantages • Variable voltage and speed design • Internal mechanism allowing for low speed, high

165

Initial testing of a variable-stroke Stirling engine  

SciTech Connect

In support of the US Department of Energy's Stirling Engine Highway Vehicle Systems Program, NASA Lewis Research Center is evaluating variable-stroke control for Stirling engines. The engine being tested is the Advenco Stirling engine; this engine was manufactured by Philips Research Laboratories of the Netherlands and uses a variable-angle swash-plate drive to achieve variable stroke operation. This report describes the engine, presents initial steady-state test data taken at Lewis, and describes a major drive system failure and subsequent modifications. Computer simulation results are presented to show potential part-load efficiency gains with variable-stroke control.

Thieme, L.G.

1985-02-01T23:59:59.000Z

166

Changes in the Economic Value of Variable Generation at High...  

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

Levels: A Pilot Case Study of California Title Changes in the Economic Value of Variable Generation at High Penetration Levels: A Pilot Case Study of California Publication Type...

167

Variability in electricity demand highlights potential roles for ...  

U.S. Energy Information Administration (EIA)

Demand-response programs and technologies that tend to reduce the variability of hourly electric demand and the resulting supply requirement would reduce the need ...

168

Multi-winding Homopolar Electric Machine Offers Variable Voltage ...  

Wind Energy Industrial Technologies Multi-winding Homopolar Electric Machine Offers Variable Voltage at Low Rotational Speed Oak Ridge National Laboratory. Contact ...

169

Free piston variable-stroke linear-alternator generator ...  

A free-piston variable stroke linear-alternator AC power generator for a combustion engine. An alternator mechanism and oscillator system generates AC current. The ...

170

The Discrete Variable Method for the Time Dependent and ...  

Science Conference Proceedings (OSTI)

... Abstract: The discrete variable representation (DVR) has been found to be a very effective approach for the numerical solution of the Schroedinger ...

2011-01-12T23:59:59.000Z

171

Process for applying control variables having fractal structures  

DOE Patents (OSTI)

A process and apparatus for the application of a control variable having a fractal structure to a body or process. The process of the present invention comprises the steps of generating a control variable having a fractal structure and applying the control variable to a body or process reacting in accordance with the control variable. The process is applicable to electroforming where first, second and successive pulsed-currents are applied to cause the deposition of material onto a substrate, such that the first pulsed-current, the second pulsed-current, and successive pulsed currents form a fractal pulsed-current waveform.

Bullock, IV, Jonathan S. (Oak Ridge, TN); Lawson, Roger L. (Oliver Springs, TN)

1996-01-01T23:59:59.000Z

172

Institute of Computer Science Limited-memory projective variable ...  

E-Print Network (OSTI)

Institute of Computer Science. Academy of Sciences of the Czech Republic. Limited-memory projective variable metric methods for unconstrained minimization.

173

Einstein x-ray observations of cataclysmic variables  

SciTech Connect

Observations with the imaging x-ray detectors on the Einstein Observatory have led to a large increase in the number of low luminosity x-ray sources known to be associated with cataclysmic variable stars (CVs). The high sensitivity of the Einstein instrumentation has permitted study of their short timescale variability and spectra. The data are adding significantly to our knowledge of the accretion process in cataclysmic variables and forcing some revision in our ideas concerning the origin of the optical variability in these stars.

Mason, K.O.; Cordova, F.A.

1982-01-01T23:59:59.000Z

174

Variable Selection and Sensitivity Analysis via Dynamic Trees...  

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

trees, this approach allows for dynamic (sequential) variable selection with fully Bayesian evidence and sensitivity indices not previously enjoyed. Compared with GPs, it...

175

Variable Renewable Generation Can Provide Balancing Control to...  

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

Variable Renewable Generation Can Provide Balancing Control to the Electric Power System e Active Power Control Helps Maintain System Frequency As wind and solar plants become more...

176

Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems  

E-Print Network (OSTI)

Amarnath, M. Blatt, Variable refrigerant flow: where, why,simulation in the variable refrigerant flow air-conditioningsimulation of the variable refrigerant flow air conditioning

Hong, Tainzhen

2010-01-01T23:59:59.000Z

177

Intraseasonal Variability in a Two-Layer Model and Observations  

Science Conference Proceedings (OSTI)

A two-layer shallow-water model with R15 truncation and topographic forcing is used to study intraseasonal variability in the Northern Hemisphere’s (NH’s) extratropical atmosphere. The model’s variability is dominated by oscillations with average ...

Christian L. Keppenne; Steven L. Marcus; Masahide Kimoto; Michael Ghil

2000-04-01T23:59:59.000Z

178

Holographic Dark Energy Model with Modified Variable Chaplygin Gas  

E-Print Network (OSTI)

In this letter we consider a correspondence between holographic dark energy and variable modified Chaplygin gas to obtain a holographic dark energy model of the universe. The corresponding potential of the scalar field has been reconstructed which describes the modified variable Chaplygin gas. The stability of the holographic dark energy in this case is also discussed.

B. C. Paul

2010-06-17T23:59:59.000Z

179

Drivers of Variability in the South Asian Monsoon  

E-Print Network (OSTI)

Drivers of Variability in the South Asian Monsoon Announcement of Opportunity Outline Bids Deadline) jointly invite outline bid proposals for research on drivers of variability in the South Asian Monsoon. For ESSO-MoES, this activity forms part of their Monsoon Mission programme (http

Edinburgh, University of

180

Fuzzy logic system for variable message signs in Kuala Lumpur  

Science Conference Proceedings (OSTI)

Intelligent Transportation Systems refer to a wide variety of advanced and emerging technology applications designed mainly to reduce traffic congestion and emissions, and to improve highway efficiency, safety, and convenience. Variable message signs ... Keywords: fuzzy controller, fuzzy logic, intelligent transportation systems, variable message signs

Arash Moradkhani Roshandeh; Majid Joshani; Othman Che Puan

2009-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Minimising the delta test for variable selection in regression problems  

Science Conference Proceedings (OSTI)

The problem of selecting an adequate set of variables from a given data set of a sampled function becomes crucial by the time of designing the model that will approximate it. Several approaches have been presented in the literature although recent studies ... Keywords: FBS, GAs, delta test, forward-backward search, genetic algorithms, hybrid algorithms, parallel architectures, regression problems, tabu search, variable selection

Alberto Guillen; Dusan Sovilj; Amaury Lendasse; Fernando Mateo; Ignacio Rojas

2008-03-01T23:59:59.000Z

182

Problems of Cosmological Variability of Fundamental Physical Constants  

E-Print Network (OSTI)

of the fundamental constants which govern most of the common phenomena and are usually given in the handbooks. NoteProblems of Cosmological Variability of Fundamental Physical Constants #3; D. A. Varshalovich, A. Y and astronomical observations aimed at testing the possible space-time variability of fundamental physical

183

New SX Phoenicis Variables in the Globular Cluster NGC 4833  

E-Print Network (OSTI)

We report the discovery of 6 SX Phoenicis stars in the southern globular cluster NGC 4833. Images were obtained from January through June 2011 with the Southeastern Association for Research in Astronomy 0.6 meter telescope located at Cerro Tololo Interamerican Observatory. The image subtraction method of Alard & Lupton (1998)was used to search for variable stars in the cluster. We confirmed 17 previously cataloged variables by Demers & Wehlau(1977). In addition to the previously known variables we have identified 10 new variables. Of the total number of confirmed variables in our 10x10 arcmin^2 field, we classified 10 RRab variables, with a mean period of 0.69591 days, 7 RRc, with a mean period of 0.39555 days, 2 possible RRe variables with a mean period of 0.30950 days, a W Ursae Majoris contact binary, an Algol-type binary, and the 6 SX Phoenicis stars with a mean period of 0.05847 days. The periods, relative numbers of RRab and RRc variables, and Bailey diagram are indicative of the cluster being o...

Darragh, Andrew N

2012-01-01T23:59:59.000Z

184

Sliding mode control law for a variable speed wind turbine  

Science Conference Proceedings (OSTI)

Modern wind turbines are designed in order to work in variable speed operations. To perform this task, wind turbines are provided with adjustable speed generators, like the double feed induction generator. One of the main advantage of adjustable speed ... Keywords: modeling and simulation, variable structure control, wind turbine control

Oscar Barambones; Jose Maria Gonzalez De Durana; Patxi Alkorta; Jose Antonio Ramos; Manuel De La Sen

2011-02-01T23:59:59.000Z

185

Development of Clemson variable-rate lateral irrigation system  

Science Conference Proceedings (OSTI)

Crops in the Southern United States are generally produced in fields which are known to have a high degree of variability in soil type, water holding capacity, infiltration rates, and other major factors which affect crop production. In these fields, ... Keywords: Instrumentation, Irrigation, Lateral-move, Precision agriculture, Variable-rate irrigation

Young J. Han; Ahmad Khalilian; Tom O. Owino; Hamid J. Farahani; Sam Moore

2009-08-01T23:59:59.000Z

186

Grothendieck bialgebras, partition lattices, and symmetric functions in noncommutative variables  

E-Print Network (OSTI)

We show that the Grothendieck bialgebra of the semi-tower of partition lattice algebras is isomorphic to the graded dual of the bialgebra of symmetric functions in noncommutative variables. In particular this isomorphism singles out a canonical new basis of the symmetric functions in noncommutative variables which would be an analogue of the Schur function basis for this bialgebra.

N. Bergeron; C. Hohlweg; M. Rosas; M. Zabrocki

2006-01-01T23:59:59.000Z

187

An open source tool for heart rate variability spectral analysis  

Science Conference Proceedings (OSTI)

In this paper we describe a software package for developing heart rate variability analysis. This package, called RHRV, is a third party extension for the open source statistical environment R, and can be freely downloaded from the R-CRAN repository. ... Keywords: Apnea, Heart rate variability, Open source, Signal processing

L. Rodríguez-Lińares; A. J. Méndez; M. J. Lado; D. N. Olivieri; X. A. Vila; I. Gómez-Conde

2011-07-01T23:59:59.000Z

188

RESEARCH ARTICLE Empirical assessment of short-term variability from  

E-Print Network (OSTI)

RESEARCH ARTICLE Empirical assessment of short-term variability from utility-scale solar PV plants grid because additional system resources are required to maintain the grid's reliability. In this study-term variability; PV plant ramp rate; daily aggregate ramp rate; inverter shells *Correspondence Rob van Haaren

189

Solving connected row convex constraints by variable elimination  

Science Conference Proceedings (OSTI)

We propose an algorithm for the class of connected row convex constraints. In this algorithm, we introduce a novel variable elimination method to solve the constraints. This method is simple and able to make use of the sparsity of the problem instances. ... Keywords: Connected row convex constraints, Constraint composition, Constraint satisfaction problems, Path consistency, Variable elimination

Yuanlin Zhang; Satyanarayana Marisetti

2009-08-01T23:59:59.000Z

190

Heart Rate Variability (HRV) in Ambient Magnetic Fields  

Science Conference Proceedings (OSTI)

In a healthy individual, the rate at which the heart beats exhibits continuous variability. In prior research at Midwest Research Institute (MRI), exposure to intermittent, but not continuous, magnetic fields was associated with alterations in heart rate variability (HRV). This report describes additional studies specifically designed to address the potential effects of magnetic field exposure on HRV.

1998-12-17T23:59:59.000Z

191

Variability of hot mix asphalt produced with reclaimed asphalt pavement  

E-Print Network (OSTI)

Pavement recycling operations have been used in the United States from the early 1900s to date. These recycling operations have been used for a variety of reasons including solid waste disposal problems, reduction of initial cost, and conservation of natural resources (aggregate, binder and energy). Adequate techniques to assess the variability of Reclaimed Asphalt Pavement (RAP) are lacking. The objectives of this research are to determine the variabilities of RAP and Hot Mix Asphalt (HMA), determine the influence of the RAP variability on the HMA variability, and compare the variability of virgin aggregates at the quarries and the aggregates that have been handled and transported to asphalt plant stockpiles. This thesis describes the compositional data analysis including the ternary diagrams for mixes and aggregates, a multivariate beta model, variability analysis using a multivariate variance assumption, and ternary quality control charts. It also describes the hypothesis tests using a k-variate student t distribution and an F-test. The following conclusions are obtained: i) RAP is better used in producing a mix with a relatively small top size 3/8" (Type S-III mix) or 1/2'' (Type S-I mix), and not with a sieve size larger than 1" (Type S-II mix); ii) RAP percent does not significantly influence the mix variability; it is desirable to use a large percentage of RAP in the Type S-I mix, i.e., more than 40% RAP; iii) On the average, the aggregate variability increases after transportation and stockpiling process; iv) On the average, the aggregate in the quarry has less variability than the same aggregate in the asphalt plant stockpile, therefore, aggregates in quarries are better controlled than aggregates in stockpiles; v) Variabilities of aggregates in quarries are slightly larger than the variability of RAP which is slightly larger than variabilities of Type S-II and S-III mixes. Type S-II and S-III mixes have the same variability and are slightly larger than the variability of the Type S-I mix; vi) The ternary diagram and the hypothesis test can be used to judge whether a contractor did a good job; vii) Ternary quality control chart shows the dynamic trend of a mix or an aggregate during the production period.

Yang, Guiqin

1999-01-01T23:59:59.000Z

192

Internal Variability of the Canadian RCM’s Hydrological Variables at the Basin Scale in Quebec and Labrador  

Science Conference Proceedings (OSTI)

The effect of a regional climate model’s (RCM’s) internal variability (IV) on climate statistics of annual series of hydrological variables is investigated at the scale of 21 eastern Canada watersheds in Quebec and Labrador. The analysis is ...

Marco Braun; Daniel Caya; Anne Frigon; Michel Slivitzky

2012-04-01T23:59:59.000Z

193

New Variable Stars in the Globular Cluster NGC 6584  

E-Print Network (OSTI)

Using the Southeastern Association for Research in Astronomy 0.6 meter telescope located at Cerro Tololo, we searched for variable stars in the southern globular cluster NGC 6584. We obtained images during 8 nights between 28 May and 6 July of 2011. After processing the images, we used the image subtraction package ISIS developed by Alard (2000)to search for the variable stars. We identified a total of 69 variable stars in our 10x10 arcmin^2 field, including 43 variables cataloged by Millis & Liller (1980) and 26 hereto unknown variables. In total, we classified 46 of the variables as type RRab, with a mean period of 0.56776 days, 15 as type RRc with a mean period of 0.30886 days, perhaps one lower amplitude type RRe, with a period of 0.26482 days, 4 eclipsing binaries, and 3 long period (P > 2 days) variable stars. As many as 15 of the RRab Lyrae stars exhibited the Blazhko Effect. Furthermore, the mean periods of the RR Lyrae types, the exhibited period/amplitude relationship, and the ratio of N_c/(N_ab...

Toddy, Joseph M; Darragh, Andrew N; Murphy, Brian W

2012-01-01T23:59:59.000Z

194

ENSEMBLE VARIABILITY OF NEAR-INFRARED-SELECTED ACTIVE GALACTIC NUCLEI  

Science Conference Proceedings (OSTI)

We present the properties of the ensemble variability V for nearly 5000 near-infrared active galactic nuclei (AGNs) selected from the catalog of Quasars and Active Galactic Nuclei (13th Edition) and the SDSS-DR7 quasar catalog. From three near-infrared point source catalogs, namely, Two Micron All Sky Survey (2MASS), Deep Near Infrared Survey (DENIS), and UKIDSS/LAS catalogs, we extract 2MASS-DENIS and 2MASS-UKIDSS counterparts for cataloged AGNs by cross-identification between catalogs. We further select variable AGNs based on an optimal criterion for selecting the variable sources. The sample objects are divided into subsets according to whether near-infrared light originates by optical emission or by near-infrared emission in the rest frame; and we examine the correlations of the ensemble variability with the rest-frame wavelength, redshift, luminosity, and rest-frame time lag. In addition, we also examine the correlations of variability amplitude with optical variability, radio intensity, and radio-to-optical flux ratio. The rest-frame optical variability of our samples shows negative correlations with luminosity and positive correlations with rest-frame time lag (i.e., the structure function, SF), and this result is consistent with previous analyses. However, no well-known negative correlation exists between the rest-frame wavelength and optical variability. This inconsistency might be due to a biased sampling of high-redshift AGNs. Near-infrared variability in the rest frame is anticorrelated with the rest-frame wavelength, which is consistent with previous suggestions. However, correlations of near-infrared variability with luminosity and rest-frame time lag are the opposite of these correlations of the optical variability; that is, the near-infrared variability is positively correlated with luminosity but negatively correlated with the rest-frame time lag. Because these trends are qualitatively consistent with the properties of radio-loud quasars reported by some previous studies, most of our sample objects are probably radio-loud quasars. Finally, we also discuss the negative correlations seen in the near-infrared SFs.

Kouzuma, S. [School of International Liberal Studies, Chukyo University, Toyota 470-0393 (Japan); Yamaoka, H., E-mail: skouzuma@lets.chukyo-u.ac.jp, E-mail: yamaoka@phys.kyushu-u.ac.jp [Department of Physics, Kyushu University, Fukuoka 812-8581 (Japan)

2012-03-01T23:59:59.000Z

195

Land Surface Controls on Hydroclimatic Means and Variability  

Science Conference Proceedings (OSTI)

Hydroclimatic means and variability are determined in large part by the control of soil moisture on surface moisture fluxes, particularly evapotranspiration and runoff. This control is examined here using a simple water balance model and ...

Randal D. Koster; Sarith P. P. Mahanama

2012-10-01T23:59:59.000Z

196

Multiple instances and symbolic variables in executable sequence charts  

Science Conference Proceedings (OSTI)

We extend live sequence charts (LSCs), a highly expressive variant of sequence diagrams, and provide the extension with an executable semantics. The extension involves support for instances that can bind to multiple objects and symbolic variables that ...

Rami Marelly; David Harel; Hillel Kugler

2002-11-01T23:59:59.000Z

197

South Atlantic Multidecadal Variability in the Climate System Model  

Science Conference Proceedings (OSTI)

Strong multidecadal variability is detected in a 300-yr integration of the NCAR Climate System Model in the South Atlantic region, through the application of two signal recognition techniques: the multitaper method and singular spectrum analysis. ...

Ilana Wainer; Silvia A. Venegas

2002-06-01T23:59:59.000Z

198

Market Design Simulations with Variable Energy Resources (VERs) (Presentation)  

Science Conference Proceedings (OSTI)

Presented at the FERC Technical Conference, 29 June 2011, Washington, D.C. This presentation describes NREL research regarding variable generation resources, operating reserves, unit commitment, economic dispatch, and introduces a new and novel modeling tool called 'FESTIV.'

Ela, E.

2011-06-01T23:59:59.000Z

199

Structure and Variability of the Kuroshio Current in Tokara Strait  

Science Conference Proceedings (OSTI)

Four years of mooring array measurements in Tokara Strait, south of Kyushu, Japan, from 1992 to 1996 are used to analyze the structure and temporal variability of the Kuroshio Current. The mean Kuroshio current in Tokara Strait shows a nearly ...

Ming Feng; Humio Mitsudera; Yasushi Yoshikawa

2000-09-01T23:59:59.000Z

200

The Evolution of Inhomogeneous Wave Statistics through a Variable Medium  

Science Conference Proceedings (OSTI)

The interaction of ocean waves with variable currents and topography in coastal areas can result in inhomogeneous statistics because of coherent interferences, which affect wave-driven circulation and transport processes. Stochastic wave models, ...

P. B. Smit; T. T. Janssen

2013-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Adaptation to Climate Variability and Change: A Guidance Manual for  

Open Energy Info (EERE)

Adaptation to Climate Variability and Change: A Guidance Manual for Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Agency/Company /Organization: United States Agency for International Development Sector: Climate, Energy, Land, Water Topics: Adaptation Resource Type: Guide/manual Website: pdf.usaid.gov/pdf_docs/PNADJ990.pdf References: Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning[1] "This Adaptation Guidance Manual is the first of several tools we are developing to assist planners and stakeholders as they cope with a changing climate. As we work with Missions to apply the methods described here, we

202

Heart rate variability in mice with coronary heart disease  

E-Print Network (OSTI)

Heart rate variability (HRV), the beat-to-beat fluctuation of the heart rate, is a non-invasive test that measures the autonomic regulation of the heart. Assessment of HRV has been shown to predict the risk of mortality ...

Zapanta, Laurence (Laurence F.)

2005-01-01T23:59:59.000Z

203

Dynamics of Interdecadal Climate Variability: A Historical Perspective  

Science Conference Proceedings (OSTI)

The emerging interest in decadal climate prediction highlights the importance of understanding the mechanisms of decadal to interdecadal climate variability. The purpose of this paper is to provide a review of our understanding of interdecadal ...

Zhengyu Liu

2012-03-01T23:59:59.000Z

204

Interannual Variability of Trace Gases in the Subtropical Winter Stratosphere  

Science Conference Proceedings (OSTI)

Measurements of water vapor and methane from the Halogen Occultation Experiment instrument on board the Upper Atmosphere Research Satellite are used to study the interannual variability of trace gas distributions in the atmosphere. Particular ...

L. J. Gray; J. M. Russell Jr.

1999-04-01T23:59:59.000Z

205

Classification of Regional Climate Variability in the State of California  

Science Conference Proceedings (OSTI)

A novel approach is presented to objectively identify regional patterns of climate variability within the state of California using principal component analysis on monthly precipitation and temperature data from a network of 195 climate stations ...

John T. Abatzoglou; Kelly T. Redmond; Laura M. Edwards

2009-08-01T23:59:59.000Z

206

Modeling Semidiurnal Internal Tide Variability in the Southern California Bight  

Science Conference Proceedings (OSTI)

The Regional Oceanic Modeling System (ROMS) is applied in a nested configuration with realistic forcing to the Southern California Bight (SCB) to analyze the variability in semidiurnal internal wave generation and propagation. The SCB has a ...

M. C. Buijsman; Y. Uchiyama; J. C. McWilliams; C. R. Hill-Lindsay

2012-01-01T23:59:59.000Z

207

Intraseasonal Variability in a Barotropic Model with Seasonal Forcing  

Science Conference Proceedings (OSTI)

It has recently been suggested that oscillatory topographic instability could contribute to low-frequency variability over the Northern Hemisphere midlatitudes. A barotropic potential vorticity model, with a hierarchy of forcing and topography ...

Christopher M. Strong; Fei-Fei Jin; Michael Ghil

1993-09-01T23:59:59.000Z

208

Joint Variability of Global Runoff and Global Sea Surface Temperatures  

Science Conference Proceedings (OSTI)

Global land surface runoff and sea surface temperatures (SST) are analyzed to identify the primary modes of variability of these hydroclimatic data for the period 1905–2002. A monthly water-balance model first is used with global monthly ...

Gregory J. McCabe; David M. Wolock

2008-08-01T23:59:59.000Z

209

Intraseasonal Variability of the West African Monsoon and Atlantic ITCZ  

Science Conference Proceedings (OSTI)

Intraseasonal variability of boreal summer rainfall and winds in tropical West Africa and the east Atlantic is examined using daily Tropical Rainfall Measuring Mission (TRMM) precipitation and the NCEP–NCAR reanalysis during 1998–2006. ...

Eric D. Maloney; Jeffrey Shaman

2008-06-01T23:59:59.000Z

210

Zonal Jet Structure and the Leading Mode of Variability  

Science Conference Proceedings (OSTI)

An observational analysis of the Northern Hemisphere circulation during winter reveals that the leading mode of variability depends on longitude. In particular, the first EOF of the zonal-mean circulation differs over the Atlantic and Pacific ...

Scott J. Eichelberger; Dennis L. Hartmann

2007-10-01T23:59:59.000Z

211

The Choice of Variable for Atmospheric Moisture Analysis  

Science Conference Proceedings (OSTI)

The implications of using different control variables for the analysis of moisture observations in a global atmospheric data assimilation system are investigated. A moisture analysis based on either mixing ratio or specific humidity is prone to ...

Dick P. Dee; Arlindo M. da Silva

2003-01-01T23:59:59.000Z

212

Decadal Variability of Two Oceans and an Atmosphere  

Science Conference Proceedings (OSTI)

A model of the midlatitude, large-scale interaction between the upper ocean and the troposphere is used to illustrate possible mechanisms of connection between the decadal variability in the North Atlantic and in the North Pacific. The two ocean ...

Blanca Gallego; Paola Cessi

2001-07-01T23:59:59.000Z

213

Spatial Distribution of Surface Fluxes Estimated from Remotely Sensed Variables  

Science Conference Proceedings (OSTI)

This study relates surface fluxes to remotely sensed variables over well-defined variations of surface wetness and vegetation. The surface fluxes are estimated from repeated Twin Otter aircraft flights at 33 m above the surface after correcting ...

Jielun Sun; L. Mahrt

1994-11-01T23:59:59.000Z

214

Spatial Variability and Interpolation of Stochastic Weather Simulation Model Parameters  

Science Conference Proceedings (OSTI)

The spatial variability of 58 precipitation and temperature parameters from the “generation of weather elements for multiple applications” (GEM) weather generator has been investigated over a region of significant complexity in topography and ...

Gregory L. Johnson; Christopher Daly; George H. Taylor; Clayton L. Hanson

2000-06-01T23:59:59.000Z

215

Evolution Dynamics of Tropical Ocean-Atmosphere Annual Cycle Variability  

Science Conference Proceedings (OSTI)

The structure of ocean-atmosphere annual cycle variability is extracted from the revised Comprehensive Ocean-Atmosphere Data Set SSTs, surface winds, and the latent heat (LH) and net shortwave (SW) surface fluxes using the covariance-based ...

Sumant Nigam; Yi Chao

1996-12-01T23:59:59.000Z

216

Global Characteristics of Stream Flow Seasonality and Variability  

Science Conference Proceedings (OSTI)

Monthly stream flow series from 1345 sites around the world are used to characterize geographic differences in the seasonality and year-to-year variability of stream flow. Stream flow seasonality varies regionally, depending on the timing of ...

Michael D. Dettinger; Henry F. Diaz

2000-08-01T23:59:59.000Z

217

Evaluation of the temporal scaling variability in forecasting ground ...  

Science Conference Proceedings (OSTI)

Aug 9, 2012 ... temporal scaling behavior and the data distribution over different .... them is not significant after introducing a new variable, the latter is ... Iberian Peninsula ( warm temperatures and high solar radiation) ..... New York: Springer.

218

Results from the NREL Variable-Speed Test bed  

DOE Green Energy (OSTI)

The NREL Variable-Speed Test bed turbine has been used to examine the performance and controllability of a variable-speed, variable-pitch turbine. Control strategies that eliminate drive-train torque fluctuations in high winds have been published before and example data are given here. The energy capture of a variable-speed wind turbine depends in part on its ability to successfully operate at the peak of the C{sub p}-{lambda} curve. The losses associated with the inability of the rotor to stay exactly on top of the curve at all have been found and quantified. New control strategies for improving energy capture in moderate winds are also proposed. The potential exists to improve overall energy capture by 5% or more.

Fingersh, L.J.; Carlin, P.W. [National Renewable Energy Lab., Golden, CO (United States). National Wind Technology Center

1997-11-01T23:59:59.000Z

219

Multi-variable optimization of pressurized oxy-coal combustion  

E-Print Network (OSTI)

Simultaneous multi-variable gradient-based optimization with multi-start is performed on a 300 MWe wet-recycling pressurized oxy-coal combustion process with carbon capture and sequestration. The model accounts for realistic ...

Zebian, Hussam

2011-01-01T23:59:59.000Z

220

Temperature and Salinity Variability in Heterogeneous Oceanic Convection  

Science Conference Proceedings (OSTI)

In regions of active oceanic convection, such as the Labrador Sea, small- and mesoscale spatial variability is observed in the temperature and salinity fields (T and S). Often T and S structures are “density-compensated,” with the density ...

Sonya Legg; James C. McWilliams

2000-06-01T23:59:59.000Z

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


221

Simulating Random Natural Variability in Time-Varying Atmospheric...  

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

Natural Variability in Time-Varying Atmospheric Concentrations of Toxic Gas from Pipeline Ruptures Speaker(s): David J. Wilson Date: February 4, 2004 - 12:00pm Location: Bldg....

222

Enhanced MJO-like Variability at High SST  

Science Conference Proceedings (OSTI)

The authors report a significant increase in Madden–Julian oscillation (MJO)–like variability in a superparameterized version of the NCAR Community Atmosphere Model run with high sea surface temperatures (SSTs). A series of aquaplanet simulations ...

Nathan P. Arnold; Zhiming Kuang; Eli Tziperman

2013-02-01T23:59:59.000Z

223

Central-West Argentina Summer Precipitation Variability and Atmospheric Teleconnections  

Science Conference Proceedings (OSTI)

The interannual-to-multidecadal variability of central-west Argentina (CWA) summer (October–March) precipitation and associated tropospheric circulation are studied in the period 1900–2010. Precipitation shows significant quasi cycles with periods ...

Eduardo A. Agosta; Rosa H. Compagnucci

2012-03-01T23:59:59.000Z

224

Antarctic Bottom Water Variability in a Coupled Climate Model  

Science Conference Proceedings (OSTI)

The natural variability of the Weddell Sea variety of Antarctic Bottom Water (AABW) is examined in a long-term integration of a coupled climate model. Examination of passive tracer concentrations suggests that the model AABW is predominantly ...

Agus Santoso; Matthew H. England

2008-09-01T23:59:59.000Z

225

Separating forced from chaotic climate variability over the past millennium  

Science Conference Proceedings (OSTI)

Reconstructions of past climate show notable temperature variability over the past millennium, with relatively warm conditions during the ‘Medieval Climate Anomaly’ (MCA) and a relatively cold ‘Little Ice Age’ (LIA). We use multi-model simulations ...

Andrew Schurer; Gabriele Hegerl; Michael E. Mann; Simon F. B. Tett; Steven J. Phipps

226

Projection of Climate Change onto Modes of Atmospheric Variability  

Science Conference Proceedings (OSTI)

Two possible interpretations of forced climate change view it as projecting, either linearly or nonlinearly, onto the dominant modes of variability of the climate system. An evaluation of these two interpretations is performed using annual mean ...

DáithíA. Stone; Andrew J. Weaver; Ronald J. Stouffer

2001-09-01T23:59:59.000Z

227

Observed Interannual Variability of Tropical Troposphere Relative Humidity  

Science Conference Proceedings (OSTI)

Relative humidity fields from the High-Resolution Infrared Radiation Sounder (HIRS) flown on NOAA series satellites since 1979 have been used to study the seasonal aspects of the interannual variability of relative humidity in the tropical ...

Mark P. McCarthy; Ralf Toumi

2004-08-01T23:59:59.000Z

228

Intraseasonal Variability in MERRA Energy Fluxes over the Tropical Oceans  

Science Conference Proceedings (OSTI)

This paper investigates intraseasonal variability as represented by the recent NASA Global Modeling and Assimilation Office (GMAO) reanalysis, the Modern-Era Retrospective analysis for Research and Applications (MERRA). The authors examine the ...

Franklin R. Robertson; Jason B. Roberts

2012-09-01T23:59:59.000Z

229

Intraseasonal Oscillations and Interannual Variability of the Indian Summer Monsoon  

Science Conference Proceedings (OSTI)

How and to what extent the intraseasonal oscillations (ISOs) influence the seasonal mean and its interannual variability of the Indian summer monsoon is investigated using 42-yr (1956–97) daily circulation data from National Centers for ...

B. N. Goswami; R. S. Ajaya Mohan

2001-03-01T23:59:59.000Z

230

Mesoscale Variability in Denmark Strait: The PV Outflow Hypothesis  

Science Conference Proceedings (OSTI)

The outflow through Denmark Strait shows remarkable mesoscale variability characterized by the continuous formation of intense mesoscale cyclones just south of the sill. These cyclones have a diameter of about 30 km and clear signatures at the ...

Michael A. Spall; James F. Price

1998-08-01T23:59:59.000Z

231

Variability of Population-Weighted Seasonal Heating Degree Days  

Science Conference Proceedings (OSTI)

Regional and national heating fuel demand is related to both weather and population density. This study analyzes the variability of population-weighted, seasonal heating degree days for the coterminous 48 states. A risk assessment of unusual ...

Nathaniel B. Guttman

1983-03-01T23:59:59.000Z

232

Atmospheric Variability on a Zonally Symmetric Land Planet  

Science Conference Proceedings (OSTI)

Atmospheric variability an a zonally symmetric planet in the absence of external forcing anomalies is studied. With idealized boundary conditions such as the absence of ocean and topography, and by using perpetual equinox solar forcing, a 15-year ...

Lai-Yung Leung; Gerald R. North

1991-08-01T23:59:59.000Z

233

Separating Forced from Chaotic Climate Variability over the Past Millennium  

Science Conference Proceedings (OSTI)

Reconstructions of past climate show notable temperature variability over the past millennium, with relatively warm conditions during the Medieval Climate Anomaly (MCA) and a relatively cold Little Ice Age (LIA). Multimodel simulations of the past ...

Andrew P. Schurer; Gabriele C. Hegerl; Michael E. Mann; Simon F. B. Tett; Steven J. Phipps

2013-09-01T23:59:59.000Z

234

Intraseasonal and Interannual Variability of Rainfall over India  

Science Conference Proceedings (OSTI)

A gridded daily rainfall dataset prepared from observations at 3700 stations is used to analyze the intraseasonal and interannual variability of the summer monsoon rainfall over India. It is found that the major drought years are characterized by ...

V. Krishnamurthy; J. Shukla

2000-12-01T23:59:59.000Z

235

Pacific Decadal Variability: Paced by Rossby Basin Modes?  

Science Conference Proceedings (OSTI)

A systematic study is presented of decadal climate variability in the North Pacific. In particular, the hypothesis is addressed that oceanic Rossby basin modes are responsible for enhanced energy at decadal and bidecadal time scales. To this end, ...

Wilbert Weijer; Ernesto Muńoz; Niklas Schneider; François Primeau

2013-02-01T23:59:59.000Z

236

Statistical Quality of Spectral Polarimetric Variables for Weather Radar  

Science Conference Proceedings (OSTI)

Spectral polarimetry for weather radar capitalizes on both Doppler and polarimetric measurements to reveal polarimetric variables as a function of radial velocity through spectral analysis. For example, spectral differential reflectivity at a ...

Tian-You Yu; Xiao Xiao; Yadong Wang

2012-09-01T23:59:59.000Z

237

A Global Numerical Weather Prediction Model with Variable Resolution  

Science Conference Proceedings (OSTI)

A conformal transformation suggested by F. Schmidt is followed to implement a global spectral model with variable resolution. A conformal mapping is defined from a physical sphere (like the earth) to a transformed (computational) sphere. The ...

Vivek Hardiker

1997-01-01T23:59:59.000Z

238

Orthobaric Density: A Thermodynamic Variable for Ocean Circulation Studies  

Science Conference Proceedings (OSTI)

A new density variable, empirically corrected for pressure, is constructed. This is done by first fitting compressibility (or sound speed) computed from global ocean datasets to an empirical function of pressure and in situ density (or specific ...

Roland A. de Szoeke; Scott R. Springer; David M. Oxilia

2000-11-01T23:59:59.000Z

239

Sliding mode control strategy for variable speed wind turbine  

Science Conference Proceedings (OSTI)

The efficiency of the wind power conversions systems can be greatly improved using an appropriate control algorithm. In this work, a robust control for variable speed wind power generation that incorporates a doubly feed induction generator is described. ...

Oscar Barambones; Jose Maria Gonzalez De Durana

2009-09-01T23:59:59.000Z

240

Modes of Interannual and Interdecadal Variability of Pacific SST  

Science Conference Proceedings (OSTI)

The multichannel singular spectrum analysis has been used to characterize the spatio–temporal structures of interdecadal and interannual variability of SST over the Pacific Ocean from 20°S to 58°N. Using the Comprehensive Ocean–Atmosphere Data ...

Xuebin Zhang; Jian Sheng; Amir Shabbar

1998-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Biennial Variability in an Atmospheric General Circulation Model  

Science Conference Proceedings (OSTI)

Recent observational analyses have indicated that tropospheric quasi-biennial oscillations (QBs) may play a fundamental role in regulating the timing and strength of El Nińo and the Southern Oscillation. The biennial variability is examined in ...

Michael A. Alexander; Klaus M. Weickmann

1995-03-01T23:59:59.000Z

242

Interannual Variability in the Eastern Subtropical North Pacific Ocean  

Science Conference Proceedings (OSTI)

Interannual variability in the eastern subtropical North Pacific Ocean is investigated using the Naval Research Laboratory Layered Ocean Model (NLOM). Emphasis is placed on examining the nature of westward propagating Rossby waves and their ...

Alan P. Leonardi; Steven L. Morey; James J. O'Brien

2002-06-01T23:59:59.000Z

243

Confidential Direct Communications: A Quantum Approach Using Continuous Variables  

E-Print Network (OSTI)

We consider the problem of privacy in direct communications, showing how quantum mechanics can be useful to guarantee a certain level of confidentiality. In particular, we review a continuous variable approach recently ...

Mancini, Stefano

244

Multidecadal Variability in North Atlantic Tropical Cyclone Activity  

Science Conference Proceedings (OSTI)

Recent increases in Atlantic basin tropical cyclone activity since 1995 and the associated destructive U.S. landfall events in 2004 and 2005 have generated considerable interest into why there has been such a sharp upturn. Natural variability, ...

Philip J. Klotzbach; William M. Gray

2008-08-01T23:59:59.000Z

245

Generation of Picosecond Electron-bunch Trains with Variable...  

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

GENERATION OF PICOSECOND ELECTRON-BUNCH TRAINS WITH VARIABLE SPACING USING A MULTI-PULSE PHOTOCATHODE LASER M. Conde 1 , W. Gai 1 , C. Jing 1,2 , R. Konecny 1 , W. Liu 1 , D....

246

Simulation of North Atlantic Low-Frequency SST Variability  

Science Conference Proceedings (OSTI)

The role of atmospheric circulation anomalies in generating midlatitude sea surface temperature (SST) variability is investigated by means of ocean general circulation model (OGCM) experiments, in which observed winds are prescribed during the ...

Ute Luksch

1996-09-01T23:59:59.000Z

247

Global Variability of the Wavenumber Spectrum of Oceanic Mesoscale Turbulence  

Science Conference Proceedings (OSTI)

The wavenumber spectra of sea surface height from satellite altimeter observations have revealed complex spatial variability that cannot be explained by a universal theory of mesoscale turbulence. Near the edge of the core regions of high eddy ...

Yongsheng Xu; Lee-Lueng Fu

2011-04-01T23:59:59.000Z

248

Impact of Gravity Waves on Marine Stratocumulus Variability  

Science Conference Proceedings (OSTI)

The impact of gravity waves on marine stratocumulus is investigated using a large-eddy simulation model initialized with sounding profiles composited from the Variability of American Monsoon Systems (VAMOS) Ocean–Cloud–Atmosphere–Land Study ...

Qingfang Jiang; Shouping Wang

2012-12-01T23:59:59.000Z

249

Interannual and Interdecadal Variability of Thailand Summer Monsoon Season  

Science Conference Proceedings (OSTI)

Summer monsoon rains are a critical factor in Thailand’s water resources and agricultural planning and management. In fact, they have a significant impact on the country’s economic health. Consequently, understanding the variability of the summer ...

Nkrintra Singhrattna; Balaji Rajagopalan; K. Krishna Kumar; Martyn Clark

2005-06-01T23:59:59.000Z

250

Short-Term Climatic Variability of the Arctic  

Science Conference Proceedings (OSTI)

The circulation of the Arctic atmosphere undergoes large fluctuations about its monthly and annual means. The statistics of Arctic sea level pressure and temperature are evaluated in order to place Arctic atmospheric variability into the context ...

John E. Walsh; William L. Chapman

1990-02-01T23:59:59.000Z

251

Variable Speed Fan Retrofits for Computer Room Air Conditioners  

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

Variable-Speed Fan Retrofits for Computer-Room Air Conditioners Prepared for the U.S. Department of Energy Federal Energy Management Program Technology Case Study Bulletin By...

252

Groundwater Constraints on Simulated Transpiration Variability over Southeastern Australian Forests  

Science Conference Proceedings (OSTI)

A land surface scheme with and without groundwater–vegetation interactions is used to explore the impact of rainfall variability on transpiration over drought-vulnerable regions of southeastern Australia. The authors demonstrate that if ...

M. Decker; A. J. Pitman; J. P. Evans

2013-04-01T23:59:59.000Z

253

Managing forecast variability in a build-to-order environment  

E-Print Network (OSTI)

In any production environment, managing demand variability is a delicate balancing act. Firms must constantly weigh potential obsolescence costs of unused inventory (should sales not materialize) against potential expedite ...

Einhorn, Marshall

2007-01-01T23:59:59.000Z

254

Information Theory and Predictability for Low-Frequency Variability  

Science Conference Proceedings (OSTI)

A predictability framework, based on relative entropy, is applied here to low-frequency variability in a standard T21 barotropic model on the sphere with realistic orography. Two types of realistic climatology, corresponding to different heights ...

Rafail Abramov; Andrew Majda; Richard Kleeman

2005-01-01T23:59:59.000Z

255

Effects of variable wind stress on ocean heat content  

E-Print Network (OSTI)

Ocean heat content change (ocean heat uptake) has an important role in variability of the Earth's heat balance. The understanding of which methods and physical processes control ocean heat uptake needs improvement in order ...

Klima, Kelly

2008-01-01T23:59:59.000Z

256

A Study of Intraseasonal Temperature Variability in Southeastern South America  

Science Conference Proceedings (OSTI)

The main goal of this work was to conduct an intraseasonal climate variability analysis using wavelet and principal component analysis over a southeastern South American daily maximum and minimum temperature series from the end of the nineteenth ...

Gustavo Naumann; Walter M. Vargas

2012-09-01T23:59:59.000Z

257

Decadal Variability of Precipitation over Western North America  

Science Conference Proceedings (OSTI)

Decadal (>7- yr period) variations of precipitation over western North America account for 20%–50% of the variance of annual precipitation. Spatially, the decadal variability is broken into several regional [O(1000 km)] components. These decadal ...

Daniel R. Cayan; Michael D. Dettinger; Henry F. Diaz; Nicholas E. Graham

1998-12-01T23:59:59.000Z

258

Does Global Warming Cause Intensified Interannual Hydroclimate Variability?  

Science Conference Proceedings (OSTI)

The idea that global warming leads to more droughts and floods has become commonplace without clear indication of what is meant by this statement. Here, the authors examine one aspect of this problem and assess whether interannual variability of ...

Richard Seager; Naomi Naik; Laura Vogel

2012-05-01T23:59:59.000Z

259

North Atlantic Subpolar Gyre Surface Variability (1895–2009)  

Science Conference Proceedings (OSTI)

Surface temperature, salinity, and density are examined in the northeastern part of the North Atlantic subpolar gyre over the last 115 years of measurements. This region presents coherent variability in space but also between different seasons, ...

G. Reverdin

2010-09-01T23:59:59.000Z

260

Decadal Climate Variability: Is There a Tidal Connection?  

Science Conference Proceedings (OSTI)

A possible connection between oceanic tides and climate variability arises from modulations in tidally induced vertical mixing. The idea is reexamined here with emphasis on near-decadal time scales. Occasional extreme tides caused by unusually ...

Richard D. Ray

2007-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Climatic Variability at Ten Stations Across the United States  

Science Conference Proceedings (OSTI)

Ten stations are chosen for a study of climatic variability in the continental United States, using as the main criteria good geographical distribution, long-period records (since before 1900), and available daily, monthly and annual values of ...

Kevin C. Vining; John F. Griffiths

1985-04-01T23:59:59.000Z

262

Interannual Modes of Variability in Atmospheric Angular Momentum  

Science Conference Proceedings (OSTI)

The interannual variability of atmospheric angular momentum over a 26-yr period is studied regionally using monthly analyses of zonal winds derived from the global rawinsonde network. Variations in zonal-mean momentum, filtered to emphasize ...

Robert X. Black; David A. Salstein; Richard D. Rosen

1996-11-01T23:59:59.000Z

263

Mesoscale Weather Effects of Variable Snow Cover over Northeast Colorado  

Science Conference Proceedings (OSTI)

Data from the PROFS (Program for Regional Observing and Forecasting Services) surface mesonetwork have been used to document the effect of variable snow cover on atmospheric boundary layer properties cloudiness and weather conditions over north ...

Richard H. Johnson; George S. Young; James J. Toth; Raymond M. Zehr

1984-06-01T23:59:59.000Z

264

Intraseasonal Variability of the South China Sea Summer Monsoon  

Science Conference Proceedings (OSTI)

The objective of this study is to explore, based on the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalysis data, the intraseasonal variability of the South China Sea (SCS) summer monsoon (...

Jiangyu Mao; Johnny C. L. Chan

2005-07-01T23:59:59.000Z

265

Wavelet Analysis of the Interannual Variability in Southern Québec Streamflow  

Science Conference Proceedings (OSTI)

The objectives of this study are to describe the local interannual variability in southern Québec, Canada, streamflow, based on wavelet analysis, and to identify plausible climatic teleconnections that could explain these local variations. Scale-...

François Anctil; Paulin Coulibaly

2004-01-01T23:59:59.000Z

266

Climatology and Interannual Variability of North Atlantic Hurricane Tracks  

Science Conference Proceedings (OSTI)

The spatial and temporal variability of North Atlantic hurricane tracks and its possible association with the annual hurricane landfall frequency along the U.S. East Coast are studied using principal component analysis (PCA) of hurricane track ...

Lian Xie; Tingzhuang Yan; Leonard J. Pietrafesa; John M. Morrison; Thomas Karl

2005-12-01T23:59:59.000Z

267

Homoclinic Dynamics: A Scenario for Atmospheric Ultralow-Frequency Variability  

Science Conference Proceedings (OSTI)

In this paper, a link will be established between atmospheric ultralow-frequency variability (ULFV) and the occurrence of homoclinic dynamics in models of large-scale atmospheric flow. It is known that uncoupled atmosphere models possess ...

Daan T. Crommelin

2002-05-01T23:59:59.000Z

268

Low-Frequency Variability in the Wind-Driven Circulation  

Science Conference Proceedings (OSTI)

The origins of low-frequency variability in a simple homogenous ocean model, forced by a double gyre Ekman suction, are examined numerically. It is found that irregular, large amplitude vacillations in the structure of the circulation typify the ...

S. P. Meacham

2000-02-01T23:59:59.000Z

269

Indian Ocean Intraseasonal Variability in an Ocean General Circulation Model  

Science Conference Proceedings (OSTI)

The impact of atmospheric intraseasonal variability on the tropical Indian Ocean is examined with an ocean general circulation model (OGCM). The model is forced by observation-based wind stresses and surface heat fluxes from an atmospheric ...

A. Schiller; J. S. Godfrey

2003-01-01T23:59:59.000Z

270

Have Aerosols Caused the Observed Atlantic Multidecadal Variability?  

E-Print Network (OSTI)

Identifying the prime drivers of the twentieth-century multidecadal variability in the Atlantic Ocean is crucial for predicting how the Atlantic will evolve in the coming decades and the resulting broad impacts on weather ...

Zhang, Rong

271

Have Aerosols Caused the Observed Atlantic Multidecadal Variability?  

Science Conference Proceedings (OSTI)

Identifying the prime drivers of the twentieth-century multidecadal variability in the Atlantic Ocean is crucial for predicting how the Atlantic will evolve in the coming decades and the resulting broad impacts on weather and precipitation ...

Rong Zhang; Thomas L. Delworth; Rowan Sutton; Daniel L. R. Hodson; Keith W. Dixon; Isaac M. Held; Yochanan Kushnir; John Marshall; Yi Ming; Rym Msadek; Jon Robson; Anthony J. Rosati; MingFang Ting; Gabriel A. Vecchi

2013-04-01T23:59:59.000Z

272

Antarctic Sea Ice Extent Variability and Its Global Connectivity  

Science Conference Proceedings (OSTI)

This study statistically evaluates the relationship between Antarctic sea ice extent and global climate variability. Temporal cross correlations between detrended Antarctic sea ice edge (SIE) anomaly and various climate indices are calculated. ...

Xiaojun Yuan; Douglas G. Martinson

2000-05-01T23:59:59.000Z

273

Heart Rate Variability in Mice with Coronary Heart Disease  

E-Print Network (OSTI)

Heart rate variability (HRV), the beat-to-beat fluctuation of the heart rate, is a noninvasive test that measures the autonomic regulation of the heart. Assessment of HRV has been shown to predict the risk of mortality in patients after an acute myocardial infarction. Recently, the Krieger lab at MIT developed genetically engineered double knockout (dKO) mice that develop coronary artery disease accompanied by spontaneous myocardial infarctions and die at a very young age. This thesis investigated whether HRV could function as a prognostic indicator in the dKO mouse. A novel method for estimating physiological state of the mouse from the electrocardiogram using an innovative activity index was developed in order to compare HRV variables at different times while controlling for physiologic state. Traditional time and frequency domain variables were used to assess the prognostic power of HRV. Results have shown that none of the HRV variables were helpful in predicting

Laurence Zapanta; Roger G. Mark

2005-01-01T23:59:59.000Z

274

Estimation of Ultraviolet-B Irradiance under Variable Cloud Conditions  

Science Conference Proceedings (OSTI)

Methods to estimate the irradiance of ultraviolet-B (UVB; 280–320 nm) radiation are needed to assess biological effects of changes in atmospheric composition. Measurements of the spatial distribution of sky cloud cover, temporal variability of ...

Richard H. Grant; Gordon M. Heisler

2000-06-01T23:59:59.000Z

275

Understanding Space Weather: The Sun as a Variable Star  

Science Conference Proceedings (OSTI)

The American Meteorological Society has recently adopted space weather as a new core competency. This is the first in a series of papers discussing the multidisciplinary aspects of space weather. This paper concerns the physics behind solar variability, ...

Keith Strong; Julia Saba; Therese Kucera

2012-09-01T23:59:59.000Z

276

Spatiotemporal Variability of Summer Precipitation in Southeastern Arizona  

Science Conference Proceedings (OSTI)

The Walnut Gulch Experimental Watershed (WGEW) in Southeastern Arizona covers ~150 km2 and receives the majority of its annual precipitation from highly variable and intermittent summer storms during the North American monsoon. In this study the ...

Susan Stillman; Xubin Zeng; William J. Shuttleworth; David C. Goodrich; Carl L. Unkrich; Marek Zreda

277

Advanced Variable Speed Air-Source Integrated Heat Pump  

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

variable speed air-source variable speed air-source integrated heat pump (AS-IHP) - CRADA Van D. Baxter Oak Ridge National Laboratory vdb@ornl.gov; 865-574-2104 April 3, 2013 Development of advanced HVAC/WH system options for efficient residential or small commercial buildings, new const. or retrofit * ET R&D project in support of DOE/BTO Goal of 50% Reduction in Building Energy Use by 2030 IHP concept - all HVAC & WH services integrated into

278

Advanced Variable Speed Air-Source Integrated Heat Pump  

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

variable speed air-source variable speed air-source integrated heat pump (AS-IHP) - CRADA Van D. Baxter Oak Ridge National Laboratory vdb@ornl.gov; 865-574-2104 April 3, 2013 Development of advanced HVAC/WH system options for efficient residential or small commercial buildings, new const. or retrofit * ET R&D project in support of DOE/BTO Goal of 50% Reduction in Building Energy Use by 2030 IHP concept - all HVAC & WH services integrated into

279

Asian Summer Monsoon Intraseasonal Variability in General Circulation Models  

SciTech Connect

The goals of this report are: (1) Analyze boreal summer Asian monsoon intraseasonal variability general circulation models--How well do the models represent the eastward and northward propagating components of the convection and how well do the models represent the interactive control that the western tropical Pacific rainfall exerts on the rainfall over India and vice-versa? (2) Role of air-sea interactions--prescribed vs. interactive ocean; and (3) Mean monsoon vs. variability.

Sperber, K R; Annamalai, H

2004-02-24T23:59:59.000Z

280

Assessment of Commercial Space Conditioning Technologies: Variable Capacity Rooftop Units  

Science Conference Proceedings (OSTI)

Space conditioning in U.S. commercial buildings is commonly performed by a packaged air-source rooftop unit (RTU). In recent years, heating, ventilation, and air-conditioning (HVAC) manufacturers have begun to develop RTUs with higher efficiency through the implementation of variable capacity technology. Variable capacity RTUs potentially offer electric utilities a new resource for achieving energy and peak power reduction. This document aims to serve as a resource for electric utilities in ...

2013-12-16T23:59:59.000Z

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


281

Searching for Variability in the Globular Cluster Messier 4  

E-Print Network (OSTI)

Time-series data taken with the Hubble Space Telescope of a field six core radii (~5') from the center of the globular cluster Messier 4, and covering a period of about 10 weeks in early 2001, have been analyzed in search of variable objects. Various criteria were employed to select candidate variable stars. Period searches were performed on the selected candidates using phase dispersion minimization (PDM). The reliability of the PDM search results was tested using synthetic light curves of eclipsing binary stars and sinusoidal light curves of different periods. Results from this analysis showed that there are probably no eclipsing binary stars or periodic variables in our field with periods on the order of a few hours to a few days, down to limiting magnitudes of V~25 and I~24, which is consistent with the absence of contact binaries such as W Ursae Majoris systems. However, one candidate variable star does show an increase in brightness of ~0.1 magnitudes in both bandpasses, which seems to last for a few days. Possible explanations concerning the nature of this object include a binary system with a white dwarf primary and a low-mass main sequence secondary, or a BY Draconis variable star. We are able to set an upper limit to the observed fraction of photometric variability in this dataset of 0.05%.

Robert D. Ferdman; Harvey B. Richer; James Brewer; Greg G. Fahlman; Brad K. Gibson; Brad M. S. Hansen; Mark E. Huber; Rodrigo A. Ibata; Jasonjot S. Kalirai; Jaymie M. Matthews; R. Michael Rich; Jason F. Rowe; Michael M. Shara; Peter B. Stetson

2003-04-25T23:59:59.000Z

282

Rapid Variability: What do we learn from correlated mm-/gamma-ray variability in jets ?  

E-Print Network (OSTI)

Densely time sampled multi-frequency flux measurements of the extreme BL Lac object S5 0716+714 over the past three years allow us to study its broad-band variability, and the detailed underlying physics, with emphasis on the location and size of the emitting regions and the evolution with time. We study the characteristics of some prominent mm-/gamma-ray flares in the context of the shock-in-jet model and investigate the location of the high energy emission region. The rapid rise and decay of the radio flares is in agreement with the formation of a shock and its evolution, if a geometrical variation is included in addition to intrinsic variations of the source. We find evidence for a correlation between flux variations at gamma-ray and radio frequencies. A two month time-delay between gamma-ray and radio flares indicates a non-cospatial origin of gamma-rays and radio flux variations in S5 0716+714.

Rani, B; Fuhrmann, L; Lott, B; Boettcher, M; Zensus, J A

2013-01-01T23:59:59.000Z

283

Interannual Variability of the Antarctic Ozone Hole in a GCM. Part I: The Influence of Tropospheric Wave Variability  

Science Conference Proceedings (OSTI)

To study the interannual variability of the Antarctic ozone hole, a physically realistic parameterization of the chemistry responsible for severe polar ozone loss has been included in the GISS GCM. The ensuing ozone hole agrees well with ...

Drew T. Shindell; Sun Wong; David Rind

1997-09-01T23:59:59.000Z

284

Modeling the Effect of Land Surface Evaporation Variability on Precipitation Variability. Part II: Time- and Space-Scale structure  

Science Conference Proceedings (OSTI)

This is the second of a two-part article investigating the impact of variations of land surface evaporability on the interannual variability of precipitation. The first goal of this part is to analyze the relationship between the atmospheric ...

Oreste Reale; Paul Dirmeyer; Adam Schlosser

2002-08-01T23:59:59.000Z

285

Quantifying the source of reentrant line variability and the effects of processes standardization on tool availability variability  

E-Print Network (OSTI)

This thesis quantifies the sensitivity of tool availability variability with respect to product throughput and examines how Intel's High Precision Maintenance initiative can be used to minimize these effects. Tools with ...

Peavey, Milo Camp

2007-01-01T23:59:59.000Z

286

A GEFA Assessment of Observed Global Ocean Influence on U.S. Precipitation Variability: Attribution to Regional SST Variability Modes  

Science Conference Proceedings (OSTI)

This paper presents a comprehensive assessment of the observed influence of the global ocean on U.S. precipitation variability using the method of Generalized Equilibrium Feedback Assessment (GEFA), which enables an unambiguous attribution of the ...

Yafang Zhong; Zhengyu Liu; Michael Notaro

2011-02-01T23:59:59.000Z

287

A single dimensionless variable for solar chimney power plant modeling  

Science Conference Proceedings (OSTI)

The solar chimney power plant is a relatively new technology for generating electricity from solar energy. In this paper dimensional analysis is used together with engineering intuition to combine eight primitive variables into only one dimensionless variable that establishes a dynamic similarity between a prototype and its scaled models. Three physical configurations of the plant were numerically tested for similarity: fully geometrically similar, partially geometrically similar, and dissimilar types. The values of the proposed dimensionless variable for all these cases were found to be nominally equal to unity. The value for the physical plant actually built and tested previously was also evaluated and found to be about the same as that of the numerical simulations, suggesting the validity of the proposition. The physical meaning of this dimensionless (similarity) variable is also interpreted; and the connection between the Richardson number and this new variable was found. It was found also that, for a fixed solar heat flux, different-sized models that are fully or partially geometrically similar share an equal excess temperature across the roof outlet. (author)

Koonsrisuk, Atit; Chitsomboon, Tawit [School of Mechanical Engineering, Institute of Engineering, Suranaree University of Technology, Muang District, Nakhon Ratchasima 30000 (Thailand)

2009-12-15T23:59:59.000Z

288

Variable stars in the globular cluster M28 (NGC 6626)  

E-Print Network (OSTI)

We present a new search for variable stars in the Galactic globular cluster M28 (NGC 6626). The search is based on a series of BVI images obtained with the SMARTS Consortium's 1.3m telescope at Cerro Tololo Inter-American Observatory, Chile. The search was carried out using the ISIS v2.2 image subtraction package. We find a total of 25 variable stars in the field of the cluster, 9 being new discoveries. Of the newly found variables, 1 is an ab-type RR Lyrae star, 6 are c-type RR Lyrae, and 2 are long-period/semi-regular variables. V22, previously classified as a type II Cepheid, appears as a bona-fide RRc in our data. In turn, V20, previously classified as an ab-type RR Lyrae, could not be properly phased with any reasonable period. The properties of the ab-type RR Lyrae stars in M28 appear most consistent with an Oosterhoff-intermediate classification, which is unusual for bona-fide Galactic globulars clusters. However, the cluster's c-type variables do not clearly support such an Oosterhoff type, and a hybr...

Prieto, G; Ramos, R Contreras; Pritzl, B J; Smith, H A; Alonso-Garcia, J

2012-01-01T23:59:59.000Z

289

Pulsating Variable Stars in the Coma Berenices dwarf spheroidal galaxy  

E-Print Network (OSTI)

We present B, V, I time-series photometry of the Coma Berenices dwarf spheroidal galaxy, a faint Milky Way satellite, recently discovered by the Sloan Digital Sky Survey. We have obtained V, B-V and V, V-I color-magnitude diagrams that reach V~23.0-23.2 mag showing the galaxy turnoff at V~21.7 mag, and have performed the first study of the variable star population of this new Milky Way companion. Two RR Lyrae stars (a fundamental-mode -RRab- and a first overtone -RRc- pulsator) and a short period variable with period P=0.12468 days were identified in the galaxy. The RRab star has a rather long period of P_ab=0.66971 days and is about 0.2 mag brighter than the RRc variable and other non-variable stars on the galaxy horizontal branch. In the period-amplitude diagram the RRab variable falls closer to the loci of Oosterhoff type-II systems and evolved fundamental-mode RR Lyrae stars in the Galactic globular cluster M3. The average apparent magnitude of the galaxy horizontal branch, =18.64+-0.04 mag, leads to a di...

Musella, I; Clementini, G; Dall'Ora, M; Kinemuchi, K; Di Fabrizio, L; Greco, C; Marconi, M; Smith, H; Radovich, M; Beers, T

2009-01-01T23:59:59.000Z

290

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)

291

Simulating Random Natural Variability in Time-Varying Atmospheric  

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

Simulating Random Natural Variability in Time-Varying Atmospheric Simulating Random Natural Variability in Time-Varying Atmospheric Concentrations of Toxic Gas from Pipeline Ruptures Speaker(s): David J. Wilson Date: February 4, 2004 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Jeiwon Deputy Random time series are found everywhere in nature. The Brownian motion of small particles; the price of assets (stocks) in financial markets; the diffusion of individual molecules through a membrane; the ballistic deposition of nano-particles onto a lattice substrate; and the time-varying concentration fluctuations at a point downwind from a pollution source all have a common dynamic description. All are stochastic processes where the local rate of change of the variable has a natural drift back to some equilibrium state, combined with a random fluctuating component. We will

292

Bottling Electricity: Storage as a Strategic Tool for Managing Variability  

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

Bottling Electricity: Storage as a Strategic Tool for Managing Bottling Electricity: Storage as a Strategic Tool for Managing Variability and Capacity Concerns in the Modern Grid - EAC Report (December 2008) Bottling Electricity: Storage as a Strategic Tool for Managing Variability and Capacity Concerns in the Modern Grid - EAC Report (December 2008) The objectives of this report are to provide the Secretary of Energy with the Electricity Advisory Committee's proposed five-year plan for integrating basic and applied research on energy storage technology applications. This report recommends policies that the U.S. Department of Energy (DOE) should consider as it develops and implements an energy storage technologies program, as authorized by the Energy Independence and Security Act of 2007. Bottling Electricity: Storage as a Strategic Tool for Managing Variability

293

Strategies and Decision Support Systems for Integrating Variable Energy  

Open Energy Info (EERE)

Strategies and Decision Support Systems for Integrating Variable Energy Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations: Global Best Practices, Examples of Excellence and Lessons Learned Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations: Global Best Practices, Examples of Excellence and Lessons Learned Agency/Company /Organization: United States Department of Energy Sector: Climate, Energy Focus Area: Renewable Energy, Grid Assessment and Integration, Wind Topics: Best Practices Resource Type: Lessons learned/best practices, Publications, Technical report Website: www1.eere.energy.gov/wind/pdfs/doe_wind_integration_report.pdf

294

Natural Gas Variability in California: Environmental Impacts and Device  

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

Natural Gas Variability in California: Environmental Impacts and Device Natural Gas Variability in California: Environmental Impacts and Device Performance - Experimental Evaluation of Pollutant Emissions from Residential Appliances Title Natural Gas Variability in California: Environmental Impacts and Device Performance - Experimental Evaluation of Pollutant Emissions from Residential Appliances Publication Type Report LBNL Report Number LBNL-2897E Year of Publication 2009 Authors Singer, Brett C., Michael G. Apte, Douglas R. Black, Toshifumi Hotchi, Donald Lucas, Melissa M. Lunden, Anna G. Mirer, Michael Spears, and Douglas P. Sullivan Publisher Lawrence Berkeley National Laboratory City Berkeley Keywords carbon monoxide, dioxide, energy performance of buildings group, formaldehyde, indoor air quality, indoor airflow and pollutant transport, indoor environment department, liquefied natural gas, nitrogen, nitrogen oxides, particle number, pollutant exposures, ultrafine particles

295

Benchmarking Variable Cost Performance in an Industrial Power Plant  

E-Print Network (OSTI)

One of the most perplexing problems for industrial power plants committed to improving competitiveness is measuring variable cost performance over time. Because variable costs like fuel and electricity represent the overwhelming majority of power plant expenses, it is imperative to develop and deploy a tool that can help plants benchmark operating performance. This paper introduces a benchmarking methodology designed to meet this need. The "Energy Conversion Index" (ECI) ratios the "value" of utilities exported from the power plant to the actual cost of the fuel and electricity required to produce them, generating a single number or "index." Variable cost performance is benchmarked by comparing the index from one period of time to the index of another comparable period of time. Savings (or costs) attributable to excellent (or poor) performance can easily be calculated by using the former period's index to project the current period's cost.

Kane, J. F.; Bailey, W. F.

1998-04-01T23:59:59.000Z

296

Improved sample size determination for attributes and variables sampling  

Science Conference Proceedings (OSTI)

Earlier INMM papers have addressed the attributes/variables problem and, under conservative/limiting approximations, have reported analytical solutions for the attributes and variables sample sizes. Through computer simulation of this problem, we have calculated attributes and variables sample sizes as a function of falsification, measurement uncertainties, and required detection probability without using approximations. Using realistic assumptions for uncertainty parameters of measurement, the simulation results support the conclusions: (1) previously used conservative approximations can be expensive because they lead to larger sample sizes than needed; and (2) the optimal verification strategy, as well as the falsification strategy, are highly dependent on the underlying uncertainty parameters of the measurement instruments. 1 ref., 3 figs.

Stirpe, D.; Picard, R.R.

1985-01-01T23:59:59.000Z

297

Determination of variable dependence information through abstract interpretation  

E-Print Network (OSTI)

Traditional schemes for abstract interpretation-based global analysis of logic programs generally focus on obtaining procedure argument mode and type information. Variable sharing information is often given only the attention needed to preserve the correctness of the analysis. However, such sharing information can be very useful. In particular, it can be used for predicting run-time goal independence, which can eliminate costly run-time checks in interpretation in logic programs is described which infers the dependencies of the terms bound to program variables with increased precision and at all points in the execution of the program, rather than just at a procedure level. Algorithms are presented for computing abstract entry and success substitutions which extensively keep track of variable aliasing and term dependence information. The algorithms are illustrated with examples. 1

K. Muthukumar; M. Hermenegildo

1989-01-01T23:59:59.000Z

298

Integration of Variable Generation and Cost-Causation (Fact Sheet)  

DOE Green Energy (OSTI)

Variable renewable energy generation sources, such as wind and solar energy, provide benefits such as reduced environmental impact, zero fuel consumption, and low and stable costs. Advances in both technologies can reduce capital costs and provide significant control capabilities. However, their variability and uncertainty - which change with weather conditions, time of day, and season - can cause an increase in power system operating costs compared to a fully controllable power plant. Although a number of studies have assessed integration costs, calculating them correctly is challenging because it is difficult to accurately develop a baseline scenario without variable generation that properly accounts for the energy value. It is also difficult to appropriately allocate costs given the complex, nonlinear interactions between resources and loads.

Not Available

2012-09-01T23:59:59.000Z

299

Variable Iron K-alpha Lines in Seyfert 1 Galaxies  

E-Print Network (OSTI)

We find that variability of the iron K-alpha line is common in Seyfert 1 galaxies. Using data from the ASCA archive for objects that have been observed more than once during the mission, we study the time-averaged spectra from individual observations, thereby probing variability on timescales that range from days to years. Since the statistics of the data do not warrant searches for line variability in terms of a complex physical model, we use a a simple Gaussian to model the gross shape of the line, and then use the centroid energy, intensity and equivalent width as robust indicators of changes in the line profile. We find that ~70% of Seyfert 1s (ten out of fifteen) show variability in at least one of these parameters: the centroid energy, intensity, and equivalent width vary in six, four, and eight sources respectively. Due to the low S/N, limited sampling and time averaging, we consider these results to represent lower limits to the rate of incidence of variability. In most cases changes in the line do not appear to track changes in the continuum. In particular, we find no evidence for variability of the line intensity in NGC 4151, suggesting an origin in a region larger than the putative accretion disk, where most of the iron line has been thought to originate. Mkn 279 is investigated on short timescales. The time-averaged effective line energy is 6.5 keV in the galaxy rest frame. As the continuum flux increases by 20% in a few hours, the Fe K line responds with the effective line energy increasing by 0.22 keV (~10,500 km s^-1). Problems with the ASCA and Rosat calibration that affect simultaneous spectral fits are discussed in an appendix.

K. A. Weaver; J. Gelbord; T. Yaqoob

2000-08-31T23:59:59.000Z

300

Variable-Speed Wind System Design : Final Report.  

SciTech Connect

Almost from the onset of the development of wind energy conversion systems (WECS), it was known that variable-speed operation of the turbine would maximize energy capture. This study was commissioned to assess the cost, efficiency gain, reduction of the cost of energy (COE), and other operating implications of converting the existing hardware of a modern fixed-speed wind energy conversion system to variable-speed operation. The purpose of this study was to develop a preliminary design for the hardware required to allow variable-speed operation using a doubly-fed generator with an existing fixed-speed wind turbine design. The turbine selected for this study is the AWT-26 designed and built by Advanced Wind Turbines Inc. of Redmond, Washington. The lowest projected COE using this variable-speed generation system is projected to be $0.0499/kWh, compared to the lowest possible COE with fixed-speed generation which is projected to be $0.0546/kWh. This translates into a 8.6% reduction of the COE using this variable-speed generation option. The preliminary system design has advanced to where the printed circuit boards can be physically laid out based on the schematics and the system software can be written based on the control flow-charts. The core of hardware and software has been proven to be successful in earlier versions of VSG systems. The body of this report presents the results of the VSWG system development. Operation under normal and fault conditions is described in detail, the system performance for variable-speed operation is estimated and compared to the original fixed-speed system performance, and specifications for all system components (generator, power electronic converter, and system controller) are given. Costs for all components are estimated, and incremental system cost is compared to incremental energy production. Finally, operational features of the VSWG which are not available in the existing FSWG system are outlined.

Lauw, Hinan K.; Weigand, Claus H.; Marckx, Dallas A.; Electronic Power Conditioning, Inc.

1993-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Internal Versus SST-Forced Atmospheric Variability as Simulated by an Atmospheric General Circulation Model  

Science Conference Proceedings (OSTI)

The variability of atmospheric flow is analyzed by separating it into an internal part due to atmospheric dynamics only and an external (or forced) part due to the variability of sea surface temperature forcing. The two modes of variability are ...

Ali Harzallah; Robert Sadourny

1995-03-01T23:59:59.000Z

302

Variability of the South Atlantic Convergence Zone Simulated by an Atmospheric General Circulation Model  

Science Conference Proceedings (OSTI)

Interannual and decadal variability of the South Atlantic convergence zone (SACZ) during austral summer [season January–February–March (JFM)] is investigated. An attempt is made to separate the forced variability from the internal variability. ...

Marcelo Barreiro; Ping Chang; R. Saravanan

2002-04-01T23:59:59.000Z

303

Interannual variability of monsoon precipitation and local subcloud equivalent potential"! temperature#!  

E-Print Network (OSTI)

! "! Interannual variability of monsoon precipitation and local subcloud equivalent potential.hurley@yale.edu"&! "'! Keywords: monsoon, interannual variability, convective quasi-equilibrium, equivalent potential"(! temperature")! #12;! #! ABSTRACT"*! The interannual variability of monsoon precipitation is described

304

Variability of black-hole accretion discs: a theoretical study  

E-Print Network (OSTI)

modified by over 400 active volcanoes. The Sun changes its spots during the 11-year cycle while other stars vary strongly in brightness as they pulsate. In the solar case, variability is intrinsic to the astrophysical object. It can also be extrinsic if, e... of relativistic compact objects with their surroundings. Measurements of X-ray variability and theoretical studies of black-hole disc accretion have therefore been intimately related for the past 30 or 40 years. Combined, they provide a unique window...

Ferreira, Bárbara Trovăo

2010-06-08T23:59:59.000Z

305

QUEST1 VARIABILITY SURVEY. III. LIGHT CURVE CATALOG UPDATE  

Science Conference Proceedings (OSTI)

This paper reports an update to the QUEST1 (QUasar Equatorial Survey Team, Phase 1) Variability Survey (QVS) light curve catalog, which links QVS instrumental magnitude light curves to Sloan Digital Sky Survey (SDSS) objects and photometry. In the time since the original QVS catalog release, the overlap between publicly available SDSS data and QVS data has increased by 8% in sky coverage and 16,728 in number of matched objects. The astrometric matching and the treatment of SDSS masks have been refined for the updated catalog. We report on these improvements and present multiple bandpass light curves, global variability information, and matched SDSS photometry for 214,941 QUEST1 objects.

Rengstorf, A. W.; Thompson, D. L. [Purdue University Calumet, Department of Chemistry and Physics, 2200 169th St., Hammond, IN 46323 (United States); Mufson, S. L.; Honeycutt, R. K.; Adams, B.; Baltay, C.; Gebhard, M. [Indiana University, 727 E. 3rd St., Bloomington, IN 47405 (United States); Andrews, P.; Coppi, P.; Emmet, W. [Yale University, Department of Physics, P.O. Box 208121, New Haven, CT 06250-8121 (United States); Vivas, A. K.; Abad, C.; Bongiovanni, A.; Briceno, C.; Bruzual, G.; Prugna, F. Della; Hernandez, J. [Centro de Investigaciones de AstronomIa, Apartado Postal 264, Merida 5101-A (Venezuela, Bolivarian Republic of); Bailyn, C. [Yale University, Department of Astronomy, P.O. Box 208101, New Haven, CT 06250-8101 (United States); Ferrin, I.; Fuenmayor, F. [Universidad de Los Andes, Apartado Postal 26, Merida 5251 (Venezuela, Bolivarian Republic of)], E-mail: adamwr@calumet.purdue.edu (and others)

2009-03-15T23:59:59.000Z

306

NREL Variability and Reserves Analysis for the Western Interconnect (Presentation)  

DOE Green Energy (OSTI)

Additional variability and uncertainty increase reserve requirements. In this light, this presentation discusses how use of generation reserves can be optimized for managing variability and uncertainty. Conclusions of this presentation are: (1) Provided a method for calculating additional reserve requirements due to wind and solar production; (2) Method is based on statistical analysis of historical time series data; (3) Reserves are dynamic, produced for each hour; (4) Reserve time series are calculated from and synchronized to simulation data; (5) PROMOD can not model directly, but workarounds exist for regulation and spin; and (6) Other production modeling packages have varying capability for reserves modeling.

Milligan, M.; King, J.

2011-10-01T23:59:59.000Z

307

Fuel-optimal space-flight transfer solutions through a redundant adjoint variable transformation.  

E-Print Network (OSTI)

?? A transformation between minimum dimension adjoint variables and redundant adjoint variables is derived in this dissertation. The transformation is then applied between the adjoint… (more)

Lawton, John Arthur

2005-01-01T23:59:59.000Z

308

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

resource/24/ ASHRAE handbook – HVAC systems and equipments.Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Efficient Cleanrooms Efficient HVAC Water Systems: Variable-

Xu, Tengfang

2005-01-01T23:59:59.000Z

309

Role of the Indian and Pacific Oceans in the Indian Summer Monsoon Variability .  

E-Print Network (OSTI)

??The role of the Indian and Pacific sea surface temperature (SST) variability in the intraseasonal and interannual variability of the Indian summer monsoon rainfall is… (more)

Achuthavarier, Deepthi

2009-01-01T23:59:59.000Z

310

Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems  

E-Print Network (OSTI)

Comparison of energy efficiency between variable refrigeranttheir superior energy efficiency. The variable refrigerantfew studies reporting the energy efficiency of VRF systems

Hong, Tainzhen

2010-01-01T23:59:59.000Z

311

Characterization and analysis of process variability in deeply-scaled MOSFETs  

E-Print Network (OSTI)

Variability characterization and analysis in advanced technologies are needed to ensure robust performance as well as improved process capability. This thesis presents a framework for device variability characterization ...

Balakrishnan, Karthik, Ph. D. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

312

Limited Temporal Variability of Arsenic Concentrations in 20 Wells  

E-Print Network (OSTI)

Limited Temporal Variability of Arsenic Concentrations in 20 Wells Monitored for 3 Years switched their water consumption to wells that meet the local standard for As in drinking water of 50 µg if As concentrations in those wells could change over time. To address this issue, we report here precise groundwater

van Geen, Alexander

313

A Simulation of Variability of ENSO Forecast Skill  

Science Conference Proceedings (OSTI)

In many prediction schemes, the skill of long-range forecasts of ENSO events depends on the time of year. Such variability could be directly due to seasonal changes in the basic ocean-atmosphere system or due to the state of ENSO itself.

M. K. Davey; D. L. T. Anderson; S. Lawrence

1996-01-01T23:59:59.000Z

314

Modeling the Variability of the Greater Agulhas Current System  

Science Conference Proceedings (OSTI)

An eddy-permitting, regional ocean model has been used to examine the variability in the source regions of the Agulhas Current on a range of time scales. These source regions are the East Madagascar Current, the flow through the Mozambique ...

J. C. Hermes; C. J. C. Reason; J. R. E. Lutjeharms

2007-07-01T23:59:59.000Z

315

Spin as state variable for computation: prospects and perspectives  

Science Conference Proceedings (OSTI)

Recent experiments on spin devices like magnetic tunnel junctions (MTJ's), domain wall magnets (DWM) and spin valves have led to the possibility of having very high density on-chip memories and logic. While the possibility of having on-chip spin transfer ... Keywords: low power, spin device, state variable, ultra low voltage

Kaushik Roy

2012-07-01T23:59:59.000Z

316

Meager genetic variability of the human malaria agent Plasmodium vivax  

E-Print Network (OSTI)

collected from Azerbaijan, Thailand, Turkey, Venezuela, and Ethiopia. Three blood samples were ob- tained; AZE, Azerbaijan; THA, Thailand; TUR, Turkey; VEN, Venezuela; PNG, Papua New Guinea; MOZ, Mozambique variability, P. simium, which comes from South America, is more closely related to P. vivax from Azerbaijan

317

Decadal Variability in a Simplified Wind-Driven Ocean Model  

Science Conference Proceedings (OSTI)

The impact of an unsteady wind forcing on oceanic low-frequency variability is conceptually studied using a reduced-gravity shallow-water model. A time-averaged wind forcing and a simple ocean–atmosphere coupling is completed by a stochastic ...

Philip Sura; Frank Lunkeit; Klaus Fraedrich

2000-08-01T23:59:59.000Z

318

Quantum state conversion between continuous variable and qubits systems  

E-Print Network (OSTI)

We investigate how quantum state can be converted between continuous variable and qubits systems. Non-linear Jaynes-Cumings interaction Hamiltonian is introduced to accomplish the conversion. Detail analysis on the conversion of thermal state exhibits that pretty good fidelity can be achieved.

Xiao-yu Chen; Liang Han; Li-zhen Jiang

2006-10-31T23:59:59.000Z

319

Thermal Testing of Tow-Placed Variable Stiffness Panels  

E-Print Network (OSTI)

Commercial systems for precise placement of pre-preg composite tows are enabling technology that allows fabrication of advanced composite structures in which the tows may be precisely laid down along curvilinear paths within a given ply. For laminates with curvilinear tow paths, the fiber orientation angle varies continuously throughout the laminate, and is not required to be straight and parallel in each ply as in conventional composite laminates. Hence, the stiffness properties vary as a function of location in the laminate, and the associated composite structure is called a Ňvariable stiffnessÓ composite structure. Previous analytical studies indicate that variable stiffness structures have great potential for improving the structural performance of composite structures. In the present research, an experimental program has been conducted to evaluate the thermal performance of two variable stiffness panels fabricated using the Viper Fiber Placement System developed by Cincinnati Machine. These variable stiffness panels have the same layup, but one panel has overlapping tows and the other panel does not. Results of thermal tests of the variable stiffness panels are presented and com-

K. Chauncey Wu; Zafer G˙rdal

2001-01-01T23:59:59.000Z

320

The Spectrum of Loop Current Variability from Gappy Data  

Science Conference Proceedings (OSTI)

The goal of this work was to understand the rate at which large anticyclonic rings are shed from the Loop Current in the Gulf of Mexico. The northward penetration of the Loop Current is used here as a surrogate variable. Data are primarily from ...

Wilton Sturges

1992-11-01T23:59:59.000Z

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


321

Tropical Cyclone– and Monsoon-Induced Rainfall Variability in Taiwan  

Science Conference Proceedings (OSTI)

This study investigates the interannual variability of tropical cyclone (TC)- and monsoon-induced rainfall (P) in Taiwan during July–September for the period 1950–2002. To examine the relative effects of TCs and monsoons, local rainfall in Taiwan ...

Jau-Ming Chen; Tim Li; Ching-Feng Shih

2010-08-01T23:59:59.000Z

322

Mining commonalities and variabilities from natural language documents  

Science Conference Proceedings (OSTI)

A company who wishes to enter an established marked with a new, competitive product is required to analyse the product solutions of the competitors. Identifying and comparing the features provided by the other vendors might greatly help during ... Keywords: software product lines, variability mining

Alessio Ferrari, Giorgio O. Spagnolo, Felice Dell'Orletta

2013-08-01T23:59:59.000Z

323

A scalable goal-oriented approach to software variability recovery  

Science Conference Proceedings (OSTI)

Software reuse approaches, such as software product lines, can help to achieve considerable effort and cost savings in product development for sets of software systems with a significant overlap in functionality. However, in the practice many organizations ... Keywords: product lines, reverse engineering, software reuse, source code mining, variability, variant, visualization

Slawomir Duszynski

2011-08-01T23:59:59.000Z

324

Trends and Interannual Variability of Wind Speed Distributions in Minnesota  

Science Conference Proceedings (OSTI)

Near-surface wind speed variability is investigated at seven stations in and surrounding Minnesota for recent climate records of 22–35 yr in length. Analyses focus on mean annual wind speeds and on the 10th, 25th, 50th, 75th, and 90th percentiles ...

Katherine Klink

2002-11-01T23:59:59.000Z

325

Variable selection for wind power prediction using particle swarm optimization  

Science Conference Proceedings (OSTI)

Wind energy has an increasing influence on the energy supply in many countries, but in contrast to conventional power plants it is a fluctuating energy source. For its integration in the electricity supply structure it is necessary to predict the wind ... Keywords: nearest neighbour search, neural network, particle swarm optimization, variable selection, wind power prediction

René Jursa

2007-07-01T23:59:59.000Z

326

Regional Interdecadal Variability in Bias-Corrected Ocean Temperature Data  

Science Conference Proceedings (OSTI)

Regional interdecadal variability, on subbasin to basin scales, is shown to be a robust feature of the post–World War II (WWII) historical temperature record, even after a recently proposed bias correction to XBT fall rates is applied. This study ...

Mark Carson; D. E. Harrison

2010-06-01T23:59:59.000Z

327

Variability of the Indian Summer Monsoon and Tropical Circulation Features  

Science Conference Proceedings (OSTI)

The Indian economy is very closely linked with the variable performance of the summer monsoon. The incidence of dry and wet conditions over the country has been examined for the period 1871–1978 by examining the normal monsoon rainfall and its ...

D. A. Mooley; B. Parthasarathy

1983-05-01T23:59:59.000Z

328

Variability aware SVM macromodel based design centering of analog circuits  

Science Conference Proceedings (OSTI)

Design centering is the term used for a procedure of obtaining enhanced parametric yield of a circuit despite the variations in device and design parameters. The process variability in nanometer regimes manifest into variations in these devices and design ... Keywords: Analog circuit sizing, Design centering, Genetic algorithm, Macromodels, Support vector machine, Yield

D. Boolchandani; Lokesh Garg; Sapna Khandelwal; Vineet Sahula

2012-10-01T23:59:59.000Z

329

Platform effects on optical variability and prediction of underwater visibility  

E-Print Network (OSTI)

Platform effects on optical variability and prediction of underwater visibility Grace Chang,1, specifically the breakdown of stratification from mixing by the hull of R/P FLIP. Modeled underwater radiance Successful, rapid identification of underwater tar- gets and accurate underwater imaging are critical

You, Yu

330

Analysis and Modeling of the Natural Variability of Climate  

Science Conference Proceedings (OSTI)

After removing annual variability, power spectral analyses of local atmospheric temperature from hundreds of stations and ice core records have been carried out from timescales of 1 day to 200 kyr. A clear sequence of power-law behaviors is found ...

Jon D. Pelletier

1997-06-01T23:59:59.000Z

331

The Globular Cluster NGC 5286. II. Variable Stars  

E-Print Network (OSTI)

We present the results of a search for variable stars in the globular cluster NGC 5286, which has recently been suggested to be associated with the Canis Major dwarf spheroidal galaxy. 57 variable stars were detected, only 19 of which had previously been known. Among our detections one finds 52 RR Lyrae (22 RRc and 30 RRab), 4 LPV's, and 1 type II Cepheid of the BL Herculis type. Periods are derived for all of the RR Lyrae as well as the Cepheid, and BV light curves are provided for all the variables. The mean period of the RRab variables is = 0.656 days, and the number fraction of RRc stars is N(c)/N(RR) = 0.42, both consistent with an Oosterhoff II (OoII) type -- thus making NGC 5286 one of the most metal-rich ([Fe/H] = -1.67; Harris 1996) OoII globulars known to date. The minimum period of the \\RRab's, namely Pab,min = 0.513 d, while still consistent with an OoII classification, falls towards the short end of the observed Pab,min distribution for OoII globular clusters. As was recently found in the case o...

Zorotovic, M; Smith, H A; Pritzl, B J; Aguirre, P; Angulo, R E; Aravena, M; Assef, R J; Contreras, C; Cortes, C; De Martini, G; Escobar, M E; González, D; Jofre, P; Lacerna, I; Navarro, C; Palma, O; Prieto, G E; Recabarren, E; Trivino, J; Vidal, E

2009-01-01T23:59:59.000Z

332

Quantifying the Variable Effects of Systems with Demand Response Resources  

E-Print Network (OSTI)

Quantifying the Variable Effects of Systems with Demand Response Resources Anupama Kowli and George, USA Abstract--The growing environmental concerns and increasing electricity prices have led to wider implementation of demand- side activities and created a new class of consumers, called de- mand response

Gross, George

333

Seasonal Kinetic Energy Variability of Near-Inertial Motions  

Science Conference Proceedings (OSTI)

Seasonal variability of near-inertial horizontal kinetic energy is examined using observations from a series of McLane Moored Profiler moorings located at 39°N, 69°W in the western North Atlantic Ocean in combination with a one-dimensional, depth-...

Katherine E. Silverthorne; John M. Toole

2009-04-01T23:59:59.000Z

334

Total Solar Irradiance Variability and the Solar Activity Cycle  

E-Print Network (OSTI)

It is suggested that the solar variability is due to the perturbed nature of the solar core and this variability is provided by the variability of the solar neutrino flux from the solar neutrino detectors i.e., Homestake, Superkamiokande, SAGE and GALLEX-GNO. The solar neutrino flux in the standard solar model (SSM) was calculated on the assumption of L_nu (neutrino luminosity) = L_gamma (optical luminosity) which implies that if there is a change in optical luminosity then solar neutrino flux data will also be changed. An internal dynamo due to the cyclic variation of nuclear energy generation inside the core of the sun is responsible for the solar activity cycle was suggested and thus the internal magnetic field is also variable. Again the changes in the nuclear energy generation induce structural changes that result in variations of the global solar parameters i.e., luminosity, radius and temperatures etc. From the analysis of total solar irradiance (TSI) data during the year from 1970 to 2003 we have foun...

Raychaudhuri, P

2006-01-01T23:59:59.000Z

335

Hybrid fuzzy-mechanistic models for addressing parameter variability  

Science Conference Proceedings (OSTI)

A simulation approach which integrates mechanistic models and fuzzy logic in order to accommodate parameter variability is developed and explored. The approach modifies a mechanistic model, such as a runoff model, for which the values of the parameters ... Keywords: Algal concentration modelling, Fuzzy logic, Model parameters, Modelling, Runoff modelling

Nicolas Lauzon; Barbara J. Lence

2008-05-01T23:59:59.000Z

336

Solar activity and earth rotation variability R. Abarca del Rioa,  

E-Print Network (OSTI)

Solar activity and earth rotation variability R. Abarca del Rioa, *, D. Gambisb , D. Salsteinc , P to investigate a possible connection with solar activity fluctuations from interannual to secular time scales in AAM and LOD agrees with that in solar activity with regard to the decadal cycle in the stratospheric

Dai, Aiguo

337

Total Solar Irradiance Variability and the Solar Activity Cycle  

E-Print Network (OSTI)

It is suggested that the solar variability is due to the perturbed nature of the solar core and this variability is provided by the variability of the solar neutrino flux from the solar neutrino detectors i.e., Homestake, Superkamiokande, SAGE and GALLEX-GNO. The solar neutrino flux in the standard solar model (SSM) was calculated on the assumption of L_nu (neutrino luminosity) = L_gamma (optical luminosity) which implies that if there is a change in optical luminosity then solar neutrino flux data will also be changed. An internal dynamo due to the cyclic variation of nuclear energy generation inside the core of the sun is responsible for the solar activity cycle was suggested and thus the internal magnetic field is also variable. Again the changes in the nuclear energy generation induce structural changes that result in variations of the global solar parameters i.e., luminosity, radius and temperatures etc. From the analysis of total solar irradiance (TSI) data during the year from 1970 to 2003 we have found five phases within the solar activity cycle. The first phase (I) starts before two years from the sunspot minimum. The second phase (II) starts at the time of sunspot minimum and phase (III) starts before 2/3 years from sunspot maximum whereas phase (IV) starts at sunspot maximum and fifth phase (V) starts at after 2-3 years from sunspot maximum.

Probhas Raychaudhuri

2006-01-16T23:59:59.000Z

338

Cartel Pricing Dynamics with Cost Variability and Endogenous Buyer Detection  

E-Print Network (OSTI)

of the cartel price to cost is most easily seen for large trends in cost. In Figure 1-b, cost rises over periodsCartel Pricing Dynamics with Cost Variability and Endogenous Buyer Detection Joseph E. Harrington characterizes collusive pricing patterns when buyers may detect the presence of a cartel. Buyers are assumed

Niebur, Ernst

339

Variable-energy drift-tube linear accelerator  

SciTech Connect

A linear accelerator system includes a plurality of post-coupled drift-tubes wherein each post coupler is bistably positionable to either of two positions which result in different field distributions. With binary control over a plurality of post couplers, a significant accumlative effect in the resulting field distribution is achieved yielding a variable-energy drift-tube linear accelerator.

Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM); Potter, James M. (Los Alamos, NM); Stovall, James E. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

340

Variable Selection for Five-Minute Ahead Electricity Load Forecasting  

Science Conference Proceedings (OSTI)

We use autocorrelation analysis to extract 6 nested feature sets of previous electricity loads for 5-minite ahead electricity load forecasting. We evaluate their predictive power using Australian electricity data. Our results show that the most important ... Keywords: very short-term electricity load forecasting, prediction, variable selection, autocorrelation analysis

Irena Koprinska; Rohen Sood; Vassilios Agelidis

2010-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Variability of consumer impacts from energy efficiency standards  

SciTech Connect

A typical prospective analysis of the expected impact of energy efficiency standards on consumers is based on average economic conditions (e.g., energy price) and operating characteristics. In fact, different consumers face different economic conditions and exhibit different behaviors when using an appliance. A method has been developed to characterize the variability among individual households and to calculate the life-cycle cost of appliances taking into account those differences. Using survey data, this method is applied to a distribution of consumers representing the U.S. Examples of clothes washer standards are shown for which 70-90% of the population benefit, compared to 10-30% who are expected to bear increased costs due to new standards. In some cases, sufficient data exist to distinguish among demographic subgroups (for example, low income or elderly households) who are impacted differently from the general population. Rank order correlations between the sampled input distributions and the sampled output distributions are calculated to determine which variability inputs are main factors. This ''importance analysis'' identifies the key drivers contributing to the range of results. Conversely, the importance analysis identifies variables that, while uncertain, make so little difference as to be irrelevant in deciding a particular policy. Examples will be given from analysis of water heaters to illustrate the dominance of the policy implications by a few key variables.

McMahon, James E.; Liu, Xiaomin

2000-06-15T23:59:59.000Z

342

Annual Cycle and Variability of the North Brazil Current  

Science Conference Proceedings (OSTI)

Current meter observations from an array of three subsurface moorings located on the Brazil continental slope near 4°N are used to describe the annual cycle and low-frequency variability of the North Brazil Current (NBC). The moored array was ...

W. E. Johns; T. N. Lee; R. C. Beardsley; J. Candela; R. Limeburner; B. Castro

1998-01-01T23:59:59.000Z

343

Investigation of the Brazil Current front variability from altimeter data  

E-Print Network (OSTI)

Investigation of the Brazil Current front variability from altimeter data Gustavo J. Goni Atlantic, Brazil Abstract. The southwestern Atlantic Ocean is characterized by the confluence of the Brazil in conjunction with a two-layer dynamical ocean scheme to monitor the Brazil Current front and to investigate its

344

Visualizing Spatial and Temporal Variability in Coastal Observatories  

Science Conference Proceedings (OSTI)

In this paper, we describe a set of 3D and 4D visualization tools and techniques for CORIE, a complex environmental observation and forecasting system (EOFS) for the Columbia River. The Columbia River, a complex and highly variable estuary, is the target ... Keywords: coastal observatories, environmental observation and forecasting systems, coasts, estuaries, Columbia River

Walter H. Jimenez; Wagner T. Correa; Claudio T. Silva; Baptista Baptista

2003-10-01T23:59:59.000Z

345

Time Scale and Feedback of Zonal-Mean-Flow Variability  

Science Conference Proceedings (OSTI)

The physical processes that determine the time scale of zonal-mean-flow variability are examined with an idealized numerical model that has a zonally symmetric lower boundary. In the part of the parameter space where the time-mean zonal flow is ...

Seok-Woo Son; Sukyoung Lee; Steven B. Feldstein; John E. Ten Hoeve

2008-03-01T23:59:59.000Z

346

Predictive Inference Using Latent Variables with Lynne Steuerle Schofield  

E-Print Network (OSTI)

institutionally-generated PV methodology and find it applies with greater generality than shown previously. When latent proficiency is an independent variable, we show that the standard institu- tional PV methodology with high reliability and precision, due to their efficient use of assessment data. Econometricians, policy

347

Understanding Variability and Uncertainty of Photovoltaics for Integration with the  

E-Print Network (OSTI)

Efficiency and Renewable Energy and by the Office of Electricity Delivery and Energy Reliability of the U of Electricity Delivery and Energy Reliability (Permitting, Siting, and Analysis Division) of the U.S. Department and analysis are needed to understand the variability of photovoltaic (PV) plants to avoid unnecessary barriers

348

Regional Dynamics of Seasonal Variability in the South China Sea  

Science Conference Proceedings (OSTI)

Dynamics of the seasonal cycle of sea surface height (SSH) in the South China Sea (SCS) are studied using observations as well as numerical and theoretical models. Seasonal variability of the SCS is interpreted in light of large-scale dynamics ...

Zhengyu Liu; Haijun Yang; Qinyu Liu

2001-01-01T23:59:59.000Z

349

A variable voltage MPPT control method for photovoltaic generation system  

Science Conference Proceedings (OSTI)

To increase the output efficiency of a photovoltaic (PV) generation system it is important to have an efficient maximum power point tracking (MPPT) technique. This paper describes the analysis, design and implementation of an efficient tracking method ... Keywords: maximum power point tracking (MPPT), photovoltaic generation system, pulse-width-modulation (PWM), solar energy, variable voltage

Liu Liqun; Wang Zhixin

2009-04-01T23:59:59.000Z

350

Eddy-Induced Instability for Low-Frequency Variability  

Science Conference Proceedings (OSTI)

Synoptic eddy–mean flow interaction has been recognized as one of the key sources for extratropical low-frequency variability. In this paper, the underlying dynamics of this interaction are examined from the perspective of a synoptic eddy-induced ...

F-F. Jin

2010-06-01T23:59:59.000Z

351

Coherent State Distinguishability in Continuous Variable Quantum Cryptography  

E-Print Network (OSTI)

We use the probability of error as a measure of distinguishability between two pure and two mixed symmetric coherent states in the context of continuous variable quantum cryptography. We show that the two mixed symmetric coherent states (in which the various components have the same real part) never give an eavesdropper more information than two pure coherent states.

Christian Weedbrook; Mile Gu; Andrew M. Lance; Thomas Symul; Ping Koy Lam; Timothy C. Ralph

2007-03-15T23:59:59.000Z

352

Variable-reluctance motors for electric vehicle propulsion  

SciTech Connect

This paper discusses the design, operation, and expected performance of a 60-kW variable-reluctance motor and inverter-designed for electric vehicle propulsion. To substantiate the performance of this system, experimental data obtained with a prototype 3.8-kW motor and inverter are provided.

Vallese, F.J.; Lang, J.H.

1985-01-01T23:59:59.000Z

353

A low power, variable resolution two-step flash ADC  

Science Conference Proceedings (OSTI)

In this paper, a new low power and configurable resolution two step flash ADC is proposed. Comparators of conventional flash ADC are replaced with CMOS inverters whose threshold can be varied dynamically. A novel peak-detector circuit is employed to ... Keywords: low power, two-step flash ADC, variable resolution

Mahesh Kumar Adimulam; Krishna Kumar Movva; Sreehari Veeramachaneni; N. Moorthy Muthukrishnan; M. B. Srinivas

2010-05-01T23:59:59.000Z

354

LQG Controller for a Variable Speed Pitch Regulated Wind Turbine  

Science Conference Proceedings (OSTI)

This paper deals with the design of LQG controllers for pitch regulated, variable speed wind turbines where the controller is used primarily for controlling the pitch angle through a collective pitch angle in the high wind speed in order to guarantee ... Keywords: LQG controller, Pitch control, Wind Trubine

Xingjia Yao; Shu Liu; Guangkun Shan; Zuoxia Xing; Changchun Guo; Chuanbao Yi

2009-08-01T23:59:59.000Z

355

NREL Sheds Light on Integration Costs of Variable Generation and  

E-Print Network (OSTI)

, such as wind and solar energy, provide benefits such as reduced environmental impact, lack of fuel consumption, and low and stable costs. However, their variability and uncertainty--which can change with weather and not unique to wind and solar. Key Result Operational changes--such as wind and solar forecasting, larger

356

A Search for Rapid Photometric Variability in Symbiotic Binaries  

E-Print Network (OSTI)

We report on our survey for rapid (time scale of minutes) photometric variability in symbiotic binaries. These binaries are becoming an increasingly important place to study accretion onto white dwarfs since they are candidate Type Ia supernovae progenitors. Unlike in most cataclysmic variables, the white dwarfs in symbiotics typically accrete from a wind, at rates greater than or equal to 10^{-9} solar masses per year. In order to elucidate the differences between symbiotics and other white dwarf accretors, as well as search for magnetism in symbiotic white dwarfs, we have studied 35 primarily northern symbiotic binaries via differential optical photometry. Our study is the most comprehensive to date of rapid variability in symbiotic binaries. We have found one magnetic accretor, Z And, previously reported by Sokoloski & Bildsten (1999). In four systems (EG And, BX Mon, CM Aql, and BF Cyg), some evidence for flickering at a low level (roughly 10 mmag) is seen for the first time. These detections are, however, marginal. For 25 systems, we place tight upper limits (order of mmag) on both aperiodic and periodic variability, highlighting a major difference between symbiotics and cataclysmic variables. The remaining five of the objects included in our sample (the 2 recurrent novae RS Oph and T CrB, plus CH Cyg, o Ceti, and MWC 560) had previous detections of large-amplitude optical flickering, and we present our extensive observations of these systems in a separate paper. We discuss the impact of our results on the ``standard'' picture of wind-fed accretion, and speculate on the possibility that in most symbiotics, light from quasi-steady nuclear burning on the surface of the white dwarf hides the fluctuating emission from accretion.

J. L. Sokoloski; Lars Bildsten; Wynn C. G. Ho

2001-04-02T23:59:59.000Z

357

Structure Function Analysis of Long Term Quasar Variability  

E-Print Network (OSTI)

In our second paper on long-term quasar variability, we employ a much larger database of quasars than in de Vries, Becker & White. This expanded sample, containing 35165 quasars from the Sloan Digital Sky Survey Data Release 2, and 6413 additional quasars in the same area of the sky taken from the 2dF QSO Redshift Survey, allows us to significantly improve on our earlier conclusions. As before, all the historic quasar photometry has been calibrated onto the SDSS scale by using large numbers of calibration stars around each quasar position. We find the following: (1) the outbursts have an asymmetric light-curve profile, with a fast-rise, slow-decline shape; this argues against a scenario in which micro-lensing events along the line-of-sight to the quasars are dominating the long-term variations in quasars; (2) there is no turnover in the Structure Function of the quasars up to time-scales of ~40 years, and the increase in variability with increasing time-lags is monotonic and constant; and consequently, (3) there is not a single preferred characteristic outburst time-scale for the quasars, but most likely a continuum of outburst time-scales, (4) the magnitude of the quasar variability is a function of wavelength: variability increases toward the blue part of the spectrum, (5) high-luminosity quasars vary less than low-luminosity quasars, consistent with a scenario in which variations have limited absolute magnitude. Based on this, we conclude that quasar variability is intrinsic to the Active Galactic Nucleus, is caused by chromatic outbursts / flares with a limited luminosity range and varying time-scales, and which have an overall asymmetric light-curve shape. Currently the model that has the most promise of fitting the observations is based on accretion disk instabilities.

W. H. de Vries; R. H. Becker; R. L. White; C. Loomis

2004-11-12T23:59:59.000Z

358

The Coordinated Control of a Central Air Conditioning System Based on Variable Chilled Water Temperature and Variable Chilled Water Flow  

E-Print Network (OSTI)

At present, regulation of water flow by means of pump frequency conversion is one of the major methods for power-saving in central air conditioning systems. In this article, optimization regulation for central air conditioning system on the basis of coordinative optimization control for variable chilled water temperature and variable chilled water flow to obtain better power savings is put forward. According to typical meteorological year data, hourly air conditioning load of whole year for every typical room has been calculated with the transmission function method. In order to guarantee each typical room, the highest cooling load rate is used as an input parameter for optimization calculation. Based on the surface cooler check model, the smallest energy consumption of chiller and chiller water pump was taken as the objective function of the optimization model. The performance characteristics of a chiller, water pump, regulation valve and pipeline are taken into account, and the optimization chilled water temperature and chilled water flow were carried out. The case study for a commercial building in Guangzhou showed that the annual power consumption of the chillers and pumps of the air conditioning system is lower by 17% only with employment of variable water flow regulation by pump frequency conversion. In the case of optimization control with coordinative control of variable chilled water temperature and variable chilled water flow, the annual power consumption of the chillers and pumps of the air conditioning system is reduced by 22% in presence of remarkable power saving effects. Increasing the chilled water temperature will reduce the dehumidified capability of the air cooler, and the indoor relative humidity will increase. The simulation showed that the adjustment optimized process meets the comfort of each typical room. The lower the cooling load rate is, the more obvious the effect of power-saving is. The highest power-saving rate appears in December, which is 36.7%. Meanwhile, the least rate appears in July, which is only 14.5%.

Liu, J.; Mai, Y.; Liu, X.

2006-01-01T23:59:59.000Z

359

Neighborhood-based Variable Ordering Heuristics for the Constraint Satisfaction Problem  

E-Print Network (OSTI)

One of the key factors in the efficiency of backtracking algorithms is the rule they use to decide on which variable to branch next (namely, the variable ordering heuristics). In this paper, we give a formulation of dynamic variable ordering heuristics that takes into account the properties of the neighborhood of the variable.

Christian Bessičre; Assef Chmeiss; Lakhdar Saďs

2001-01-01T23:59:59.000Z

360

Variable Speed Fan Retrofits for Computer Room Air Conditioners  

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

Variable-Speed Fan Variable-Speed Fan Retrofits for Computer-Room Air Conditioners Prepared for the U.S. Department of Energy Federal Energy Management Program Technology Case Study Bulletin By Lawrence Berkeley National Laboratory Steve Greenberg September 2013 2 Contacts Steve Greenberg Lawrence Berkeley National Laboratory One Cyclotron Road, 90R3111 Berkeley, California 94720 (510) 486-6971 segreenberg@lbl.gov For more information on FEMP, please contact: Will Lintner, P.E., CEM Federal Energy Management Program U.S. Department of Energy 1000 Independence Ave. S.W. Washington, D. C. 20585-0121 (202) 586-3120 william.lintner@ee.doe.gov 3 Acknowledgements EPRI: Dennis Symanski, Brian Fortenbery Synapsense: Garret Smith, Patricia Nealon Vigilent: Corinne Vita

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361

Bio-Med Variable Field MRI Project | Superconducting Magnet Division  

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

Bio-Med Variable Field MRI Project Bio-Med Variable Field MRI Project One of the Research and Development projects currently underway is the Bio-Med magnet. Destined for use within the solenoidal field of an MRI, it is designed for use where the subject, in this case a rat, must be tracked in order to obtain an image. Typical MRIs require the subject to remain stationary, and a rat will not normally oblige when it is awake. By moving the composite field (MRI Solenoid plus Bio-Med dipole) to track the rat, it is possible to allow the rat some freedom of motion, while still imaging the brain functions. For the rapid movement typical of a rat, the Bio-Med coil magnet must be capable of very rapid changes in field. Superconducting magnets are typically not designed to allow rapid field variations. To do so typically

362

A Catalog and Atlas of Cataclysmic Variables - The Living Edition  

E-Print Network (OSTI)

The Catalog and Atlas of Cataclysmic Variables (Edition 1 - 1993) and Edition 2 - 1997) has been a valuable source of information for the cataclysmic variable (CV) community. However, the goal of having a central location for all objects is slowly being lost as each new edition is generated. There can also be a long time delay between new information becoming available on an object and its publication in the catalog. To eliminate these concerns, as well as to make the catalog more accessible, we have created a web site which will contain a ``living'' edition of the catalog. We have also added orbital period information, as well as finding charts for novae, to the catalog.

Downes, R A; Shara, M M; Ritter, H G; Kolb, U; Duerbeck, H W; Ritter, Hans; Kolb, Ulrich; Duerbeck, Hilmar W.

2001-01-01T23:59:59.000Z

363

Analysis of a teetered, variable-speed rotor: final report  

DOE Green Energy (OSTI)

A computer model of a horizontal axis wind turbine (HOOT) with four structural degrees of freedom has been derived and verified. The four degrees of freedom include flapwise motion of the blades, teeter motion, and variable rotor speed. Options for the variable rotor speed include synchronous, induction, and constant-tip speed generator models with either start, stop, or normal operations. Verification is made by comparison with analytical solutions and mean and cyclic ESI-80 data. The Veers full-field turbulence model is used as a wind input for a synchronous and induction generator test case during normal operation. As a result of the comparison, it is concluded that the computer model can be used to predict accurately mean and cyclic loads with a turbulent wind input. 47 refs., 19 figs.

Weber, T.L.; Wilson, R.E.; Walker, S.N. (Oregon State Univ., Corvallis, OR (USA). Dept. of Mechanical Engineering) [Oregon State Univ., Corvallis, OR (USA). Dept. of Mechanical Engineering

1991-06-01T23:59:59.000Z

364

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.

365

Interannual variability of summer monsoon rainfall onset date across India  

E-Print Network (OSTI)

Variability of Indian summer monsoon onset dates is investigated at 1-degree spatial resolution by applying an agronomic definition (i.e. the first significant rains without a potentially damaging dry spell thereafter) to gridded observed daily rainfall data (1951–2003). Median onset dates compare well with previous estimates. The inter-quartile range varies from less than two weeks over the monsoon zone and western Ghats, to about a month over the northwestern desert. Local onset date is shown to be poorly correlated with regional-scale definitions of monsoon onset, and this is attributed to low estimates of spatial coherence, found for local onset-date variability. There is a weak relationship between local onset date and the June–September seasonal rainfall total, while the latter is shown to be more spatially coherent—and thus more potential predictable—over the monsoon zone than local onset date. 1.

Vincent Moron; Andrew W. Robertson

2009-01-01T23:59:59.000Z

366

Continuous variable quantum teleportation with non-Gaussian resources  

E-Print Network (OSTI)

We investigate continuous variable quantum teleportation using non-Gaussian states of the radiation field as entangled resources. We compare the performance of different classes of degaussified resources, including two-mode photon-added and two-mode photon-subtracted squeezed states. We then introduce a class of two-mode squeezed Bell-like states with one-parameter dependence for optimization. These states interpolate between and include as subcases different classes of degaussified resources. We show that optimized squeezed Bell-like resources yield a remarkable improvement in the fidelity of teleportation both for coherent and nonclassical input states. The investigation reveals that the optimal non-Gaussian resources for continuous variable teleportation are those that most closely realize the simultaneous maximization of the content of entanglement, the degree of affinity with the two-mode squeezed vacuum and the, suitably measured, amount of non-Gaussianity.

Dell'Anno, F; Farias, L Albano; Illuminati, F

2007-01-01T23:59:59.000Z

367

Anisotropic high temperature superconductors as variable resistors and switches  

Science Conference Proceedings (OSTI)

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

368

Variable Stars in Large Magellanic Cloud Globular Clusters III: Reticulum  

E-Print Network (OSTI)

This is the third in a series of papers studying the variable stars in old globular clusters in the Large Magellanic Cloud. The primary goal of this series is to look at how the characteristics and behavior of RR Lyrae stars in Oosterhoff-intermediate systems compare to those of their counterparts in Oosterhoff-I/II systems. In this paper we present the results of our new time-series BVI photometric study of the globular cluster Reticulum. We found a total of 32 variables stars (22 RRab, 4 RRc, and 6 RRd stars) in our field of view. We present photometric parameters and light curves for these stars. We also present physical properties, derived from Fourier analysis of light curves, for some of the RR Lyrae stars. We discuss the Oosterhoff classification of Reticulum and use our results to re-derive the distance modulus and age of the cluster.

Kuehn, Charles A; Smith, Horace A; Catelan, Márcio; Jeon, Young-Beom; Nemec, James M; Walker, Alistair R; Kunder, Andrea; Pritzl, Barton J; De Lee, Nathan; Borissova, Jura

2013-01-01T23:59:59.000Z

369

Compile-time Derivation of Variable Dependency Using Abstract Interpretation  

E-Print Network (OSTI)

Traditional schemes for abstract interpretation-based global analysis of logic programs generally focus on obtaining procedure argument mode and type information. Variable sharing information is often given only the attention needed to preserve the correctness of the analysis. However, such sharing information can be very useful. In particular, it can be used for predicting runtime goal independence, which can eliminate costly run-time checks in and-parallel execution. In this paper, a new algorithm for doing abstract interpretation in logic programs is described which concentrates on inferring the dependencies of the terms bound to program variables with increased precision and at all points in the execution of the program, rather than just at a procedure level. Algorithms are presented for computing abstract entry and success substitutions which extensively domain independent fixpoint algorithm is presented and described in detail. The algorithms are illustrated with examples. Finally, results from an implementation of the abstract interpreter are presented. 1

K. Muthukumar; M. Hermenegildo

1992-01-01T23:59:59.000Z

370

Bayesian Modeling of Population Variability -- Practical Guidance and Pitfalls  

SciTech Connect

With the advent of easy-to-use open-source software for Markov chain Monte Carlo (MCMC) simulation, hierarchical Bayesian analysis is gaining in popularity. This paper presents practical guidance for hierarchical Bayes analysis of typical problems in probabilistic safety assessment (PSA). The guidance is related to choosing parameterizations that accelerate convergence of the MCMC sampling and to illustrating the potential sensitivity of the results to the functional form chosen for the first-stage prior. This latter issue has significant ramifications because the mean of the average population variability curve (PVC) from hierarchical Bayes (or the mean of the point estimate distribution from empirical Bayes) can be very sensitive to this choice in cases where variability is large. Numerical examples are provided to illustrate the issues discussed.

Dana L. Kelly; Corwin L. Atwood

2008-05-01T23:59:59.000Z

371

Design of a variable-conductance vacuum insulation  

DOE Green Energy (OSTI)

This paper describes one approach to the design of a variable-conductance vacuum insulation. In this design, the vacuum insulation consists of a permanently sealed, thin sheet steel, evacuated envelope of whatever geometry is required for the application. The steel envelope is supported internally against the atmospheric pressure loads by an array of discrete, low-conductance, ceramic supports, and radiative heat transfer is blocked by layers of thin metal radiation shields. Thermal conductance through this insulation is controlled electronically by changing the temperature of a small metal hydride connected to the vacuum envelope. The hydride reversibly absorbs/desorbs hydrogen to produce a hydrogen pressure typically within the range from less than 10{sup {minus}6} to as much as 1 torr. Design calculations are compared with results from laboratory tests of bench scale samples, and some possible automotive applications for this variable-conductance vacuum insulation are suggested.

Benson, D K; Potter, T F; Tracy, C E

1994-01-01T23:59:59.000Z

372

Continuous variable entanglement distillation of Non-Gaussian Mixed States  

E-Print Network (OSTI)

Many different quantum information communication protocols such as teleportation, dense coding and entanglement based quantum key distribution are based on the faithful transmission of entanglement between distant location in an optical network. The distribution of entanglement in such a network is however hampered by loss and noise that is inherent in all practical quantum channels. Thus, to enable faithful transmission one must resort to the protocol of entanglement distillation. In this paper we present a detailed theoretical analysis and an experimental realization of continuous variable entanglement distillation in a channel that is inflicted by different kinds of non-Gaussian noise. The continuous variable entangled states are generated by exploiting the third order non-linearity in optical fibers, and the states are sent through a free-space laboratory channel in which the losses are altered to simulate a free-space atmospheric channel with varying losses. We use linear optical components, homodyne mea...

Dong, Ruifang; Heersink, Joel; Marquardt, Christoph; Filip, Radim; Leuchs, Gerd; Andersen, Ulrik L

2010-01-01T23:59:59.000Z

373

Continuous variable quantum teleportation with non-Gaussian resources  

E-Print Network (OSTI)

We investigate continuous variable quantum teleportation using non-Gaussian states of the radiation field as entangled resources. We compare the performance of different classes of degaussified resources, including two-mode photon-added and two-mode photon-subtracted squeezed states. We then introduce a class of two-mode squeezed Bell-like states with one-parameter dependence for optimization. These states interpolate between and include as subcases different classes of degaussified resources. We show that optimized squeezed Bell-like resources yield a remarkable improvement in the fidelity of teleportation both for coherent and nonclassical input states. The investigation reveals that the optimal non-Gaussian resources for continuous variable teleportation are those that most closely realize the simultaneous maximization of the content of entanglement, the degree of affinity with the two-mode squeezed vacuum and the, suitably measured, amount of non-Gaussianity.

F. Dell'Anno; S. De Siena; L. Albano Farias; F. Illuminati

2007-06-25T23:59:59.000Z

374

Continuous-variable quantum teleportation with non-Gaussian resources  

SciTech Connect

We investigate continuous variable quantum teleportation using non-Gaussian states of the radiation field as entangled resources. We compare the performance of different classes of degaussified resources, including two-mode photon-added and two-mode photon-subtracted squeezed states. We then introduce a class of two-mode squeezed Bell-like states with one-parameter dependence for optimization. These states interpolate between and include as subcases different classes of degaussified resources. We show that optimized squeezed Bell-like resources yield a remarkable improvement in the fidelity of teleportation both for coherent and nonclassical input states. The investigation reveals that the optimal non-Gaussian resources for continuous variable teleportation are those that most closely realize the simultaneous maximization of the content of entanglement, the degree of affinity with the two-mode squeezed vacuum, and the, suitably measured, amount of non-Gaussianity.

Dell'Anno, F. [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy); Dipartimento di Fisica, Universita degli Studi di Salerno, Via S. Allende, I-84081 Baronissi (Italy); CNR-INFM Coherentia, Napoli, Italy and CNISM Unita di Salerno and INFN Sezione di Napoli, Gruppo Collegato di Salerno, Baronissi (Italy); De Siena, S. [Dipartimento di Fisica, Universita degli Studi di Salerno, Via S. Allende, I-84081 Baronissi (Italy); CNR-INFM Coherentia, Napoli, Italy and CNISM Unita di Salerno and INFN Sezione di Napoli, Gruppo Collegato di Salerno, Baronissi (Italy); Albano, L. [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy); CNR-INFM Coherentia, Napoli, Italy and CNISM Unita di Salerno and INFN Sezione di Napoli, Gruppo Collegato di Salerno, Baronissi (Italy); Illuminati, F. [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy); CNR-INFM Coherentia, Napoli, Italy and CNISM Unita di Salerno and INFN Sezione di Napoli, Gruppo Collegato di Salerno, Baronissi (Italy); ISI Foundation for Scientific Interchange, Viale Settimio Severo 65, 00173 Turin (Italy)

2007-08-15T23:59:59.000Z

375

Free piston variable-stroke linear-alternator generator  

DOE Patents (OSTI)

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

Haaland, Carsten M. (Dadeville, AL)

1998-01-01T23:59:59.000Z

376

Forecasting Economic and Financial Variables with Global VARs  

E-Print Network (OSTI)

Suppose one were interested in forecasting output growth and inflation across a number of different countries; how would one go about it? What additional variables might help in such forecasting (the oil price comes to mind), and should one also consider... .2. Ideally evaluation is done with a separate sample, though that can often be prohibitively costly, one reason why techniques like cross-validation have considerable appeal. Essentially these first two stages can be considered as trading off bias (build...

Pesaran, M Hashem; Schuermann, Til; Smith, L Vanessa

377

Influence of solar and cosmic-ray variability on climate  

E-Print Network (OSTI)

We analyze solar, geomagnetic and cosmic ray flux data along with rainfall and temperature data for almost five solar cycles. We provide evidence of significant influence of solar variability on climate. Specifically, we demonstrate association between lower (higher) rainfall and higher (lower) temperatures with increasing (decreasing) solar activity and decreasing (increasing) cosmic ray intensities. We propose a plausible scenario that accounts the results of our analysis.

Badruddin,; Singh, M

2013-01-01T23:59:59.000Z

378

Balancing Options for the Integration of Variable Generation  

Science Conference Proceedings (OSTI)

Significant Challenges There are significant operating challenges to integrate VG on a large scale due to VG ramping, uncertainty and production counter to demand Variability and uncertainty not new scale is increased with VG May need approx. 50 GW of Balancing Resources by 2030 potential resources may include (but not limited to): Demand Side Resources New gas turbines and Conventional Generation Energy Storage (non pumped hydro) Plug In Electric Vehicles Pumped Hydro Markets, VGPM and other enabling ...

2011-12-30T23:59:59.000Z

379

Advanced Planning Method for Integrating Large-Scale Variable Generation  

Science Conference Proceedings (OSTI)

As the penetration and size of renewable generation resources increase, the industry must expand transmission infrastructure to accommodate increasing renewable resource output. Conventional transmission expansion planning requires sufficient transmission capacities to transfer the full name plate capacity of all power plants to load centers at the same time. However, renewable resources, such as wind and solar, have highly variable output and are spatially diversified. Thus, transmission expansion plann...

2009-12-22T23:59:59.000Z

380

Non-flat time-variable dark energy cosmology  

E-Print Network (OSTI)

We generalize the time-variable dark energy scalar field $\\Phi$ model ($\\Phi$CDM) to non-flat space. We show that even in the space-curvature-dominated epoch the scalar field solution is a time-dependent fixed point or attractor, with scalar field energy density that grows relative to the energy density in spatial curvature. This is the first example of a physically consistent and complete model of dynamical dark energy in a non-flat geometry.

Pavlov, Anatoly; Saaidi, Khaled; Ratra, Bharat

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Spatial and Temporal Variability of Aerosol Particles in Arctic Spring  

SciTech Connect

The objective of this work is to investigate the variability in the particle number concentration that may affect climate change assessment for Arctic regions. The Indirect and Semi-Direct Aerosol Campaign (ISDAC) was conducted in April 2008, in the vicinities of Fairbanks and Barrow, Alaska. Measurements of particle number concentrations and size distributions were conducted using a Passive Cavity Aerosol Spectrometer Probe (PCASP-100X) mounted under the Convair-580 aircraft wing. Total number concentration of particles (Na) with diameters in the range 0.12-3 ?m was determined for polluted and clean air masses during times when the air was free of clouds and/or precipitation. Variability in Na was considered for both vertical profiles and constant altitude (horizontal) flight legs. This variability can have important implications for estimates of particle properties used in global climate model (GCM) simulations. When aerosol particle layers were encountered, Na rapidly increased from 25 cm-3 up to 550 cm-3 within relatively clean air masses, and reached up to 2200 cm-3 within polluted air masses, dominated by biomass burning pollution. When averaging Na over different distance scales, it was found that Na=140 cm-3 represent an average value for the majority of the encountered clean cases; while Na=720 cm-3 is a mean for polluted cases dominated by biomass burning plumes. These estimates, however, would not capture the details of particle layers encountered during most of the flights. Average aerosol particle characteristics can be difficult to interpret, especially during polluted cases, due to small-scale spatial and temporal variability.

Shantz, Nicole C.; Gultepe, Ismail; Liu, Peter; Earle, Michael; Zelenyuk, Alla

2012-10-01T23:59:59.000Z

382

Quantification and scaling of multipartite entanglement in continuous variable systems  

E-Print Network (OSTI)

We present a theoretical method to determine the multipartite entanglement between different partitions of multimode, fully or partially symmetric Gaussian states of continuous variable systems. For such states, we determine the exact expression of the logarithmic negativity and show that it coincides with that of equivalent two--mode Gaussian states. Exploiting this reduction, we demonstrate the scaling of the multipartite entanglement with the number of modes and its reliable experimental estimate by direct measurements of the global and local purities.

Gerardo Adesso; Alessio Serafini; Fabrizio Illuminati

2004-06-09T23:59:59.000Z

383

Variability in Measured Space Temperatures in 60 Homes  

SciTech Connect

This report discusses the observed variability in indoor space temperature in a set of 60 homes located in Florida, New York, Oregon, and Washington. Temperature data were collected at 15-minute intervals for an entire year, including living room, master bedroom, and outdoor air temperature (Arena, et. al). The data were examined to establish the average living room temperature for the set of homes for the heating and cooling seasons, the variability of living room temperature depending on climate, and the variability of indoor space temperature within the homes. The accuracy of software-based energy analysis depends on the accuracy of input values. Thermostat set point is one of the most influential inputs for building energy simulation. Several industry standards exist that recommend differing default thermostat settings for heating and cooling seasons. These standards were compared to the values calculated for this analysis. The data examined for this report show that there is a definite difference between the climates and that the data do not agree well with any particular standard.

Roberts, D.; Lay, K.

2013-03-01T23:59:59.000Z

384

Extrinsic Radio Variability of JVAS/CLASS Gravitational Lenses  

E-Print Network (OSTI)

We present flux-ratio curves of the fold and cusp (i.e. close multiple) images of six JVAS/CLASS gravitational lens systems. The data were obtained over a period of 8.5 months in 2001 with the Multi-Element Radio-Linked Interferometer Network (MERLIN) at 5-GHz with 50 mas resolution, as part of a MERLIN Key-Project. Even though the time delays between the fold and cusp images are small (<~1 day) compared to the time-scale of intrinsic source variability, all six lens systems show evidence that suggests the presence of extrinsic variability. In particular, the cusp images of B2045+265 -- regarded as the strongest case of the violation of the cusp relation (i.e. the sum of the magnifications of the three cusp images add to zero) -- show extrinsic variations in their flux-ratios up to ~40 percent peak-to-peak on time scales of several months. Its low Galactic latitude of b=-10 degree and a line-of-sight toward the Cygnus superbubble region suggest that Galactic scintillation is the most likely cause. The cusp images of B1422+231 at b=+69 degree do not show strong extrinsic variability. Galactic scintillation can therefore cause significant scatter in the cusp and fold relations of some radio lens systems (up to 10 percent rms), even though these relations remain violated when averaged over a <~1 year time baseline.

L. V. E. Koopmans; A. Biggs; R. D. Blandford; I. W. A. Browne; N. J. Jackson; S. Mao; P. N. Wilkinson; A. G. de Bruyn; J. Wambsganss

2003-02-11T23:59:59.000Z

385

Extremal entanglement and mixedness in continuous variable systems  

E-Print Network (OSTI)

We investigate the relationship between mixedness and entanglement for Gaussian states of continuous variable systems. We introduce generalized entropies based on Schatten $p$-norms to quantify the mixedness of a state, and derive their explicit expressions in terms of symplectic spectra. We compare the hierarchies of mixedness provided by such measures with the one provided by the purity (defined as ${\\rm tr} \\varrho^2$ for the state $\\varrho$) for generic $n$-mode states. We then review the analysis proving the existence of both maximally and minimally entangled states at given global and marginal purities, with the entanglement quantified by the logarithmic negativity. Based on these results, we extend such an analysis to generalized entropies, introducing and fully characterizing maximally and minimally entangled states for given global and local generalized entropies. We compare the different roles played by the purity and by the generalized $p$-entropies in quantifying the entanglement and the mixedness of continuous variable systems. We introduce the concept of average logarithmic negativity, showing that it allows a reliable quantitative estimate of continuous variable entanglement by direct measurements of global and marginal generalized $p$-entropies.

Gerardo Adesso; Alessio Serafini; Fabrizio Illuminati

2004-02-18T23:59:59.000Z

386

Extremal entanglement and mixedness in continuous variable systems  

Science Conference Proceedings (OSTI)

We investigate the relationship between mixedness and entanglement for Gaussian states of continuous variable systems. We introduce generalized entropies based on Schatten p norms to quantify the mixedness of a state and derive their explicit expressions in terms of symplectic spectra. We compare the hierarchies of mixedness provided by such measures with the one provided by the purity (defined as tr {rho}{sup 2} for the state {rho}) for generic n-mode states. We then review the analysis proving the existence of both maximally and minimally entangled states at given global and marginal purities, with the entanglement quantified by the logarithmic negativity. Based on these results, we extend such an analysis to generalized entropies, introducing and fully characterizing maximally and minimally entangled states for given global and local generalized entropies. We compare the different roles played by the purity and by the generalized p entropies in quantifying the entanglement and the mixedness of continuous variable systems. We introduce the concept of average logarithmic negativity, showing that it allows a reliable quantitative estimate of continuous variable entanglement by direct measurements of global and marginal generalized p entropies.

Adesso, Gerardo; Serafini, Alessio; Illuminati, Fabrizio [Dipartimento di Fisica 'E. R. Caianiello', Universita di Salerno, INFM UdR di Salerno, INFN Sezione di Napoli, Gruppo Collegato di Salerno, Via S. Allende, 84081 Baronissi, SA (Italy)

2004-08-01T23:59:59.000Z

387

Mass Market Demand Response and Variable Generation Integration Issues: A  

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

Mass Market Demand Response and Variable Generation Integration Issues: A Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study Title Mass Market Demand Response and Variable Generation Integration Issues: A Scoping Study Publication Type Report Refereed Designation Unknown Year of Publication 2011 Authors Cappers, Peter, Andrew D. Mills, Charles A. Goldman, Ryan H. Wiser, and Joseph H. Eto Pagination 76 Date Published 10/2011 Publisher LBNL City Berkeley Keywords demand response, electricity markets and policy group, energy analysis and environmental impacts department, renewable generation integration, smart grid Abstract The penetration of renewable generation technology (e.g., wind, solar) is expected to dramatically increase in the United States during the coming years as many states are implementing policies to expand this sector through regulation and/or legislation. It is widely understood, though, that large scale deployment of certain renewable energy sources, namely wind and solar, poses system integration challenges because of its variable and often times unpredictable production characteristics (NERC, 2009). Strategies that rely on existing thermal generation resources and improved wind and solar energy production forecasts to manage this variability are currently employed by bulk power system operators, although a host of additional options are envisioned for the near future. Demand response (DR), when properly designed, could be a viable resource for managing many of the system balancing issues associated with integrating large-scale variable generation (VG) resources (NERC, 2009). However, demand-side options would need to compete against strategies already in use or contemplated for the future to integrate larger volumes of wind and solar generation resources. Proponents of smart grid (of which Advanced Metering Infrastructure or AMI is an integral component) assert that the technologies associated with this new investment can facilitate synergies and linkages between demand-side management and bulk power system needs. For example, smart grid proponents assert that system-wide implementation of advanced metering to mass market customers (i.e., residential and small commercial customers) as part of a smart grid deployment enables a significant increase in demand response capability.1 Specifically, the implementation of AMI allows electricity consumption information to be captured, stored and utilized at a highly granular level (e.g., 15-60 minute intervals in most cases) and provides an opportunity for utilities and public policymakers to more fully engage electricity customers in better managing their own usage through time-based rates and near-real time feedback to customers on their usage patterns while also potentially improving the management of the bulk power system. At present, development of time-based rates and demand response programs and the installation of variable generation resources are moving forward largely independent of each other in state and regional regulatory and policy forums and without much regard to the complementary nature of their operational characteristics.2 By 2020, the electric power sector is expected to add ~65 million advanced meters3 (which would reach ~47% of U.S. households) as part of smart grid and AMI4 deployments (IEE, 2010) and add ~40-80 GW of wind and solar capacity (EIA, 2010). Thus, in this scoping study, we focus on a key question posed by policymakers: what role can the smart grid (and its associated enabling technology) play over the next 5-10 years in helping to integrate greater penetration of variable generation resources by providing mass market customers with greater access to demand response opportunities? There is a well-established body of research that examines variable generation integration issues as well as demand response potential, but the nexus between the two has been somewhat neglected by the industry. The studies that have been conducted are informative concerning what could be accomplished with strong broad-based support for the expansion of demand response opportunities, but typically do not discuss the many barriers that stand in the way of reaching this potential. This study examines how demand side resources could be used to integrate wind and solar resources in the bulk power system, identifies barriers that currently limit the use of demand side strategies, and suggests several factors that should be considered in assessing alternative strategies that can be employed to integrate wind and solar resources in the bulk power system. It is difficult to properly gauge the role that DR could play in managing VG integration issues in the near future without acknowledging and understanding the entities and institutions that govern the interactions between variable generation and mass market customers (see Figure ES-1). Retail entities, like load-serving entities (LSE) and aggregators of retail customers (ARC), harness the demand response opportunities of mass market customers through tariffs (and DR programs) that are approved by state regulatory agencies or local governing entities (in the case of public power). The changes in electricity consumption induced by DR as well as the changes in electricity production due to the variable nature of wind and solar generation technologies is jointly managed by bulk power system operators. Bulk power system operators function under tariffs approved by the Federal Energy Regulatory Commission (FERC) and must operate their systems in accordance with rules set by regional reliability councils. These reliability rules are derived from enforceable standards that are set by the North American Electric Reliability Corporation (NERC) and approved by federal regulators. Thus, the role that DR can play in managing VG integration issues is contingent on what opportunities state and local regulators are willing to approve and how customers' response to the DR opportunities can be integrated into the bulk power system both electrically (due to reliability rules) and financially (due to market rules).

388

Potential Reductions in Variability with Alternative Approaches to Balancing Area Cooperation with High Penetrations of Variable Generation  

SciTech Connect

The work described in this report was performed by the National Renewable Energy Laboratory (NREL) and funded by the Office of the Energy Efficiency and Renewable Energy, U.S. Department of Energy (EERE DOE). This project is a joint project with the Pacific Northwest National Laboratory. This report evaluates the physical characteristics that improve the ability of the power system to absorb variable generation. It then uses evidence from electricity markets in the Eastern Interconnection of the United States to show how large, fast energy markets can help with integration. The concept of Virtual Balancing Area is introduced, a concept that covers a broad range of cooperative measures that can be undertaken by balancing areas to help manage variability.

Milligan, M.; Kirby, B.; Beuning, S.

2010-08-01T23:59:59.000Z

389

GEOCHEMICAL MODELING OF F AREA SEEPAGE BASIN COMPOSITION AND VARIABILITY  

SciTech Connect

From the 1950s through 1989, the F Area Seepage Basins at the Savannah River Site (SRS) received low level radioactive wastes resulting from processing nuclear materials. Discharges of process wastes to the F Area Seepage Basins followed by subsequent mixing processes within the basins and eventual infiltration into the subsurface resulted in contamination of the underlying vadose zone and downgradient groundwater. For simulating contaminant behavior and subsurface transport, a quantitative understanding of the interrelated discharge-mixing-infiltration system along with the resulting chemistry of fluids entering the subsurface is needed. An example of this need emerged as the F Area Seepage Basins was selected as a key case study demonstration site for the Advanced Simulation Capability for Environmental Management (ASCEM) Program. This modeling evaluation explored the importance of the wide variability in bulk wastewater chemistry as it propagated through the basins. The results are intended to generally improve and refine the conceptualization of infiltration of chemical wastes from seepage basins receiving variable waste streams and to specifically support the ASCEM case study model for the F Area Seepage Basins. Specific goals of this work included: (1) develop a technically-based 'charge-balanced' nominal source term chemistry for water infiltrating into the subsurface during basin operations, (2) estimate the nature of short term and long term variability in infiltrating water to support scenario development for uncertainty quantification (i.e., UQ analysis), (3) identify key geochemical factors that control overall basin water chemistry and the projected variability/stability, and (4) link wastewater chemistry to the subsurface based on monitoring well data. Results from this study provide data and understanding that can be used in further modeling efforts of the F Area groundwater plume. As identified in this study, key geochemical factors affecting basin chemistry and variability included: (1) the nature or chemistry of the waste streams, (2) the open system of the basins, and (3) duration of discharge of the waste stream types. Mixing models of the archetype waste streams indicated that the overall basin system would likely remain acidic much of the time. Only an extended periods of predominantly alkaline waste discharge (e.g., >70% alkaline waste) would dramatically alter the average pH of wastewater entering the basins. Short term and long term variability were evaluated by performing multiple stepwise modeling runs to calculate the oscillation of bulk chemistry in the basins in response to short term variations in waste stream chemistry. Short term (1/2 month and 1 month) oscillations in the waste stream types only affected the chemistry in Basin 1; little variation was observed in Basin 2 and 3. As the largest basin, Basin 3 is considered the primary source to the groundwater. Modeling showed that the fluctuation in chemistry of the waste streams is not directly representative of the source term to the groundwater (i.e. Basin 3). The sequence of receiving basins and the large volume of water in Basin 3 'smooth' or nullify the short term variability in waste stream composition. As part of this study, a technically-based 'charge-balanced' nominal source term chemistry was developed for Basin 3 for a narrow range of pH (2.7 to 3.4). An example is also provided of how these data could be used to quantify uncertainty over the long term variations in waste stream chemistry and hence, Basin 3 chemistry.

Millings, M.; Denham, M.; Looney, B.

2012-05-08T23:59:59.000Z

390

Coordinated Variable Structure Switching Attacks for Smart Grid  

E-Print Network (OSTI)

The effective modeling and analysis of large-scale power system disturbances especially those stemming from intentional attack represents an open engineering and research problem. Challenges stem from the need to develop intelligent models of cyber-physical attacks that produce salient disruptions and appropriately describe meaningful cyber-physical interdependencies such that they balance precision, scale and complexity. In our research, we present a foundation for the development of a class of intelligent cyber-physical attacks termed coordinated variable structure switching attacks whereby opponents aim to destabilize the power grid through con- trolled switching sequence. Such switching is facilitated by cyber-attack and corruption of communication channels and control signals of the associated switch(es). We provide methods and theorems to construct such attack models and demonstrate their utility in the simulation of extensive system disturbances. Our proposed class of cyber-physical switching attacks for smart grid systems has the potential to disrupt large-scale power system operation within a short interval of time. Through successful cyber intrusion, an opponent can remotely apply a state- dependent coordinated switching sequence on one or more relays and circuit breakers of a power system to disrupt operation. Existence of this switching vulnerability is dependent on the local structure of the power grid. Variable structure systems theory is employed to effectively model the cyber-physical aspects of a smart grid and determine the existence of the vulnerability and construct the destabilizing switching attack sequence. We illustrate the utility of the attack approach assess its impact on the different power system test cases including the single machine infinite bus power system model and the Western Electricity Coordinating Council (WECC) 3-machine 9-bus system through MATLAB/Simulink and PSCAD simulation environment. The results demonstrate the potential of our approach for practical attack. Moreover, we build on our work in several ways. First, we extend the research to demonstrate an approach to mitigation within the variable structure system frame- work. We demonstrate via small signal analysis how through persistent switching a stable sliding mode can be used to disrupt a dynamical system that seems stable. We also design an approach to vulnerability analysis to assess the feasibility of co-ordinated variable structure switching attacks. Moreover, we study the performance of our attack construction approach when the opponent has imperfect knowledge of the local system dynamics and partial knowledge of the generator state. Based on the system with modeling errors, we study the performance of coordinated variable structure switching attacks in the presence of state estimation. Finally, we illustrate the concepts of attack model within the multiple switching framework, the cascading failure analysis is employed in the New-England 10-machine, 39-bus power system using MATLAB/Simulink and DSATools simulation environment. Our results demonstrate the potential for coordinated variable structure switching attacks to enable large-scale power system disturbances.

Liu, Shan

2013-05-01T23:59:59.000Z

391

HIGH LEVEL WASTE SLUDGE BATCH 4 VARIABILITY STUDY  

Science Conference Proceedings (OSTI)

The Defense Waste Processing Facility (DWPF) is preparing for vitrification of High Level Waste (HLW) Sludge Batch 4 (SB4) in early FY2007. To support this process, the Savannah River National Laboratory (SRNL) has provided a recommendation to utilize Frit 503 for vitrifying this sludge batch, based on the composition projection provided by the Liquid Waste Organization on June 22, 2006. Frit 418 was also recommended for possible use during the transition from SB3 to SB4. A critical step in the SB4 qualification process is to demonstrate the applicability of the durability models, which are used as part of the DWPF's process control strategy, to the glass system of interest via a variability study. A variability study is an experimentally-driven assessment of the predictability and acceptability of the quality of the vitrified waste product that is anticipated from the processing of a sludge batch. At the DWPF, the durability of the vitrified waste product is not directly measured. Instead, the durability is predicted using a set of models that relate the Product Consistency Test (PCT) response of a glass to the chemical composition of that glass. In addition, a glass sample is taken during the processing of that sludge batch, the sample is transmitted to SRNL, and the durability is measured to confirm acceptance. The objective of a variability study is to demonstrate that these models are applicable to the glass composition region anticipated during the processing of the sludge batch - in this case the Frit 503 - SB4 compositional region. The success of this demonstration allows the DWPF to confidently rely on the predictions of the durability/composition models as they are used in the control of the DWPF process.

Fox, K; Tommy Edwards, T; David Peeler, D; David Best, D; Irene Reamer, I; Phyllis Workman, P

2006-10-02T23:59:59.000Z

392

Temporal and spatial variability of surface temperature over Texas  

E-Print Network (OSTI)

Surface temperature is one of the most fundamental aspects of the climate system, and its study has been the focus of extensive research in the field of climatology for years. Examination of its temporal and spatial fluctuations can provide scientists with information on the behavior of the atmospheric circulation. Many researchers have also been interested in the physical processes and mechanisms at work in producing the observed distribution of the surface temperature field over the globe. Various analytical methods are used in the study of temperature variability on the Earth. White and Wallace (1978) documented the annual march of surface temperature by mapping amplitudes and phases of the seasonal cycle. The latter were obtained through Fourier analysis of the data. Kim and North (1991, 1992) routinely use second-moment statistics such as variance and spatial correlation to study the fluctuations of temperature in energy balance models as compared with observations. Empirical orthogonal function (EOF) analysis has become a popular and convenient method for representing the variability of climatic parameters since the groundbreaking work of Lorenz (1956). The first several EOFS, or patterns of covariability in a meteorological field, can sometimes be explained in a physical sense based on their shapes. While most previous efforts have concentrated on the global or hemispheric scale, this research examines the fluctuations of surface temperature on a regional scale, namely the state of Texas. Texas is an ideal location for a study of this type due to its vast areal extent, diverse topography, and expanse across different climatic regimes. Some of the methods used in the study of temperature variability are applied to the state of Texas.

Moninski, Anthony David

1995-01-01T23:59:59.000Z

393

Variability-selected quasars behind the Small Magellanic Cloud  

E-Print Network (OSTI)

We present followup spectroscopic observations of quasar candidates in the Small Magellanic Cloud selected by Eyer from the OGLE database. Of twelve observed objects identified as "QSO Candidate", five are confirmed quasars, with the emission redshifts ranging from 0.28 to 2.16. Two of those quasars were also recently identified independently in the MACHO database by Geha et al. We discuss the prospects of using variability-based selection technique for quasar searches behind other dense stellar fields. An additional criterion utilizing the color-color diagram should reduce the number of stars in the candidate lists.

A. Dobrzycki; L. M. Macri; K. Z. Stanek; P. J. Groot

2002-10-28T23:59:59.000Z

394

Initiative in Nuclear Theory at the Variable Energy Cyclotron Centre  

E-Print Network (OSTI)

We recall the path breaking contributions of the nuclear theory group of the Variable Energy Cyclotron Centre, Kolkata. From a beginning of just one person in 1970s, the group has steadily developed into a leading group in the country today, with seminal contributions to almost the entire range of nuclear physics, viz., low energy nuclear reactions, nuclear structure, deep inelastic collisions, fission, liquid to gas phase transitions, nuclear matter, equation of state, mass formulae, neutron stars, relativistic heavy ion collisions, medium modification of hadron properties, quark gluon plasma, and cosmology of early universe.

Srivastava, D K; Basu, D N; Chaudhuri, A K; De, J N; Krishan, K; Pal, S

2005-01-01T23:59:59.000Z

395

Initiative in Nuclear Theory at the Variable Energy Cyclotron Centre  

E-Print Network (OSTI)

We recall the path breaking contributions of the nuclear theory group of the Variable Energy Cyclotron Centre, Kolkata. From a beginning of just one person in 1970s, the group has steadily developed into a leading group in the country today, with seminal contributions to almost the entire range of nuclear physics, viz., low energy nuclear reactions, nuclear structure, deep inelastic collisions, fission, liquid to gas phase transitions, nuclear matter, equation of state, mass formulae, neutron stars, relativistic heavy ion collisions, medium modification of hadron properties, quark gluon plasma, and cosmology of early universe.

D. K. Srivastava; J. Alam; D. N. Basu; A. K. Chaudhuri; J. N. De; K. Krishan; S. Pal

2005-06-24T23:59:59.000Z

396

Variable energy flux in quasi-static magnetohydrodynamic turbulence  

E-Print Network (OSTI)

Experiments and numerical simulations show that the energy spectrum of the magnetohydrodynamic turbulence in the quasi-static limit deviates from Kolmogorov's $k^{-5/3}$ spectrum as the external magnetic field, or equivalently the interaction parameter, is increased. To explain this phenomena, we construct an analytical turbulence model with variable energy flux that arises due to the Lorentz-force induced dissipation. The energy spectra computed using our model for various interaction parameters are in qualitative agreement with earlier experimental and numerical results.

Mahendra K. Verma

2013-04-25T23:59:59.000Z

397

High power variable couplers for ladder and spoke type resonators  

Science Conference Proceedings (OSTI)

Superconducting RF structures such as spoke resonators [1] have been developed which will accelerate very low velocity ions. This opens up the possibility for the use of these resonators in high power proton accelerators at energies as low as the output energies of typical RFQs. Most similar resonators have been used for the acceleration of ions requiring only low RF power input. In new applications such as for the Accelerator Transmutation of Nuclear Wastes (ATW) and Accelerator Production of Tritium (APT), higher RF power will be required because of the larger beam currents. This paper discusses some higher power variable coupler concepts that could be used with these structures.

Spalek, G. (George); Kuzminski, J. (Jozef)

2001-01-01T23:59:59.000Z

398

On precanonical quantization of gravity in spin connection variables  

SciTech Connect

The basics of precanonical quantization and its relation to the functional Schroedinger picture in QFT are briefly outlined. The approach is then applied to quantization of Einstein's gravity in vielbein and spin connection variables and leads to a quantum dynamics described by the covariant Schroedinger equation for the transition amplitudes on the bundle of spin connection coefficients over space-time, that yields a novel quantum description of space-time geometry. A toy model of precanonical quantum cosmology based on the example of flat FLRW universe is considered.

Kanatchikov, I. V. [National Center of Quantum Information in Gdansk (KCIK), 81-824 Sopot (Poland)

2013-02-21T23:59:59.000Z

399

Variable flow control for a nuclear reactor control rod  

DOE Patents (OSTI)

A variable flow control for a control rod assembly of a nuclear reactor that depends on turbulent friction though an annulus. The annulus is formed by a piston attached to the control rod drive shaft and a housing or sleeve fitted to the enclosure housing the control rod. As the nuclear fuel is burned up and the need exists for increased reactivity, the control rods are withdrawn, which increases the length of the annulus and decreases the rate of coolant flow through the control rod assembly.

Carleton, Richard D. (Pittsburgh, PA); Bhattacharyya, Ajay (Vasteras, SE)

1978-01-01T23:59:59.000Z

400

Modeling Agents that Exhibit Variable Performance in a Collaborative Setting  

E-Print Network (OSTI)

Abstract. In a collaborative environment, knowledge about collaborators ’ skills is an important factor when determining which team members should perform a task. However, this knowledge may be incomplete or uncertain. In this paper, we extend our ETAPP (Environment-Task-Agents-Policy-Protocol) collaboration framework by modeling team members that exhibit non-deterministic performance, and comparing two alternative ways of using these models to assign agents to tasks. Our simulation-based evaluation shows that performance variability has a large impact on task performance, and that task performance is improved by consulting agent models built from a small number of observations of agents’ recent performance. 1

Ingrid Zukerman; Christian Guttmann

2005-01-01T23:59:59.000Z

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


401

Variable temperature electrochemical strain microscopy of Sm-doped ceria  

Science Conference Proceedings (OSTI)

Variable temperature electrochemical strain microscopy has been used to study the electrochemical activity of Sm-doped ceria as a function of temperature and bias. The electrochemical strain microscopy hysteresis loops have been collected across the surface at different temperatures and the relative activity at different temperatures has been compared. The relaxation behavior of the signal at different temperatures has been also evaluated to relate kinetic process during bias induced electrochemical reactions with temperature and two different kinetic regimes have been identified. The strongly non-monotonic dependence of relaxation behavior on temperature is interpreted as evidence for water-mediated mechanisms.

Jesse, Stephen [ORNL; Morozovska, A. N. [National Academy of Science of Ukraine, Kiev, Ukraine; Kalinin, Sergei V [ORNL; Eliseev, E. A. [National Academy of Science of Ukraine, Kiev, Ukraine; Yang, Nan [ORNL; Doria, Sandra [ORNL; Tebano, Antonello [ORNL

2013-01-01T23:59:59.000Z

402

Variable operation of Hall thruster with multiple segmented electrodes  

DOE Green Energy (OSTI)

Variable plasma jet velocity with low beam divergence over a range of mass flow rates can be achieved through segmented electrode operation of Hall plasma accelerator. With the use of just a cathode side electrode at the cathode potential, the beam divergence can be decreased substantially, at some cost in efficiency. However, the additional use of an anode side electrode retains the same reduced plume divergence, but at efficiencies comparable to the non-segmented operation. The high efficiency persists also when the anode side electrode is biased at an intermediate potential, thus producing two-stage Hall accelerator operation.

Fisch, N.J.; Raitses, Y.; Dorf, L.A.; Litvak, A.A.

2000-02-07T23:59:59.000Z

403

Improving continuous-variable entanglement distribution by separable states  

E-Print Network (OSTI)

We investigate the physical mechanism behind the counterintuitive phenomenon, the distribution of continuous-variable entanglement between two distant modes by sending a third separable auxiliary mode between them. For this purpose, we propose a new more simple and more efficient protocol resulting in distributed entanglement with more than an order of the magnitude higher logarithmic negativity than in the previously proposed protocol. This new protocol shows that the distributed entanglement originates from the entanglement of one mode and the auxiliary mode used for distribution which is first destroyed by local correlated noises and restored subsequently by the interference of the auxiliary mode with the second distant separable correlated mode.

Ladislav Mišta, Jr.; Natalia Korolkova

2013-04-30T23:59:59.000Z

404

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 in properly applying VFDs. The benefits and pitfalls in applying VFDs that will be addressed by this paper include- Benefits: Energy Savings, Improved Process Control, “Soft Start” Reduced Mechanical Stress, Improved Electrical System Power Factor, and Pitfalls: Motor Acoustic Noise, Motor Heating. This paper is intended for plant engineers and maintenance personnel who have some practical experience with electrical and mechanical equipment, but are not VFD experts.

Petro, D.

1993-03-01T23:59:59.000Z

405

Survey of Variable Generation Forecasting in the West: August 2011 - June 2012  

DOE Green Energy (OSTI)

This report surveyed Western Interconnection Balancing Authorities regarding their implementation of variable generation forecasting, the lessons learned to date, and recommendations they would offer to other Balancing Authorities who are considering variable generation forecasting. Our survey found that variable generation forecasting is at an early implementation stage in the West. Eight of the eleven Balancing Authorities interviewed began forecasting in 2008 or later. It also appears that less than one-half of the Balancing Authorities in the West are currently utilizing variable generation forecasting, suggesting that more Balancing Authorities in the West will engage in variable generation forecasting should more variable generation capacity be added.

Porter, K.; Rogers, J.

2012-04-01T23:59:59.000Z

406

Design of a variable gain amplifier for an ultrawideband receiver  

E-Print Network (OSTI)

A fully differential CMOS variable gain amplifier (VGA) has been designed for an ultra-wideband receiver. The VGA comprises of two variable gain stages followed by a post amplifier stage. The interface between the digital control block and the analog VGA is formed by a digital-to-analog converter and an exponential voltage generator. The gain of the VGA varies dB-linearly from 0 to 52 dB with respect to the control voltage. The VGA is operated in open loop with a bandwidth greater than 500 MHz throughout the gain range to cater to the requirements of the ultra-wideband system. The noise-to-power ratio of the VGA is -23.9 dB for 1Vp-p differential input signal in the low gain setting, and the equivalent input referred noise is 1.01 V2 for the high gain setting. All three stages use common mode feedback to fix and stabilize the output DC levels at a particular voltage depending on the input common-mode requirement of the following stage. DC offset cancellation has also been incorporated to minimize the input referred DC offset caused by systematic and random mismatches in the circuit. Compensation schemes to minimize the effects of temperature, supply and process variations have been included in the design. The circuit has been designed in 0.18??m CMOS technology, and the post layout simulations are in good agreement with the schematic simulations.

Krishnanji, Sivasankari

2005-08-01T23:59:59.000Z

407

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

408

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

409

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

410

Measurement and Modeling of Solar and PV Output Variability: Preprint  

DOE Green Energy (OSTI)

This paper seeks to understand what temporal and spatial scales of variability in global horizontal radiation are important to a PV plants and what measurements are needed to be able to characterize them. As solar radiation measuring instruments are point receivers it is important to understand how those measurements translate to energy received over a larger spatial extent. Also of importance is the temporal natural of variability over large spatial areas. In this research we use high temporal and spatial resolution measurements from multiple sensors at a site in Hawaii to create solar radiation fields at various spatial and temporal scales. Five interpolation schemes were considered and the high resolution solar fields were converted to power production for a PV power plant. It was found that the interpolation schemes are robust and create ramp distributions close to what would be computed if the average solar radiation field was used. We also investigated the possibility of using time averaged solar data from 1 sensor to recreate the ramp distribution from the 17 sensors. It was found that the ramping distribution from using appropriately time averaged data from 1 sensor can reasonably match the distribution created using the 17 sensor network.

Sengupta, M.

2011-04-01T23:59:59.000Z

411

QCD in terms of gauge-invariant dynamical variables  

E-Print Network (OSTI)

For a complete description of the physical properties of low-energy QCD, it might be advantageous to first reformulate QCD in terms of gauge-invariant dynamical variables, before applying any approximation schemes. Using a canonical transformation of the dynamical variables, which Abelianises the non-Abelian Gauss-law constraints to be implemented, such a reformulation can be achieved for QCD. The exact implementation of the Gauss laws reduces the colored spin-1 gluons and spin-1/2 quarks to unconstrained colorless spin-0, spin-1, spin-2 and spin-3 glueball fields and colorless Rarita-Schwinger fields respectively. The obtained physical Hamiltonian can then be rewritten into a form, which separates the rotational from the scalar degrees of freedom, and admits a systematic strong-coupling expansion in powers of lambda=g^{-2/3}, equivalent to an expansion in the number of spatial derivatives. The leading-order term in this expansion corresponds to non-interacting hybrid-glueballs, whose low-lying masses can be ...

Pavel, Hans-Peter

2013-01-01T23:59:59.000Z

412

FITDisk: A Cataclysmic Variable Accretion Disk Demonstration Tool  

E-Print Network (OSTI)

We present the software tool FITDisk, a precompiled-binary Windows GUI version of our smoothed particle hydrodynamics cataclysmic variable accretion disk research code. Cataclysmic variables are binary star systems in which a compact stellar remnant, typically a white dwarf star, is stripping mass from a lower-main-sequence companion star by way of an accretion disk. Typically the disk is the brightest component of the system, because the plasma is heated dramatically as it spirals down in the gravitational well of the primary white dwarf star. The shortest-period systems can display disk "superhump" oscillations driven by the rotating tidal field of the secondary star. FITDisk models these accretion disk phenomena using a fully three-dimensional hydrodynamics calculation, and data can be visualized as they are computed or stored to hard drive for later playback at a fast frame rate. Simulations are visualized using OpenGL graphics and the viewing angle can be changed interactively. Pseudo light curves of sim...

Wood, M A; Simpson, J C; Wood, Matt A.; Dolence, Josh; Simpson, James C.

2005-01-01T23:59:59.000Z

413

FITDisk: A Cataclysmic Variable Accretion Disk Demonstration Tool  

E-Print Network (OSTI)

We present the software tool FITDisk, a precompiled-binary Windows GUI version of our smoothed particle hydrodynamics cataclysmic variable accretion disk research code. Cataclysmic variables are binary star systems in which a compact stellar remnant, typically a white dwarf star, is stripping mass from a lower-main-sequence companion star by way of an accretion disk. Typically the disk is the brightest component of the system, because the plasma is heated dramatically as it spirals down in the gravitational well of the primary white dwarf star. The shortest-period systems can display disk "superhump" oscillations driven by the rotating tidal field of the secondary star. FITDisk models these accretion disk phenomena using a fully three-dimensional hydrodynamics calculation, and data can be visualized as they are computed or stored to hard drive for later playback at a fast frame rate. Simulations are visualized using OpenGL graphics and the viewing angle can be changed interactively. Pseudo light curves of simulated systems can be plotted along with the associated Fourier amplitude spectrum. FITDisk is available for free download at www.astro.fit.edu/cv/fitdisk.html.

Matt A. Wood; Josh Dolence; James C. Simpson

2005-11-11T23:59:59.000Z

414

Search for Spatial Variability in the Solar Acoustic Spectrum  

E-Print Network (OSTI)

Motivated by the various examples of spatial variability in the power of the acoustic spectrum, we attempted to look for spatial variability in the peak frequency of the spectrum. However, the determination of this peak frequency on a spatial scale of a single pixel (8 arc seconds for the GONG data) is limited by the stochastic variations in the power spectrum presumably caused by the stochastic nature of the excitation process. Averaging over a large number of spectra (100 spectra from a 10 $\\times$ 10 pixels area) produced stabler spectra. The peak frequencies of 130 such locations were found to be distributed with a FWHM of about 130 $\\mu$Hz. A map of the spatial variation of this peak frequency did not show any strong feature with statistically significant deviation from the mean of the distribution. Likewise, the scatter in the peak frequencies masked the detection of magnetic field induced changes in the peak frequency. On a much larger scale, the N latitudes showed a slightly lower value of the peak frequency as compared to the S latitudes, although the difference (25 $\\mu$Hz) is barely larger than the {\\it rms} spread (20 $\\mu$Hz).

P. Venkatakrishnan; Brajesh Kumar; S. C. Tripathy

2001-05-22T23:59:59.000Z

415

SEARCH FOR SPATIAL VARIABILITY IN THE SOLAR ACOUSTIC SPECTRUM  

E-Print Network (OSTI)

Abstract. Motivated by the various examples of spatial variability in the power of the acoustic spectrum, we attempted to look for spatial variability in the peak frequency of the spectrum. However, the determination of this peak frequency on a spatial scale of a single pixel (8 arc seconds for the GONG data) is limited by the stochastic variations in the power spectrum presumably caused by the stochastic nature of the excitation process. Averaging over a large number of spectra (100 spectra from a 10 × 10 pixels area) produced stabler spectra. The peak frequencies of 130 such locations were found to be distributed with a FWHM of about 130 µHz. A map of the spatial variation of this peak frequency did not show any strong feature with statistically significant deviation from the mean of the distribution. Likewise, the scatter in the peak frequencies masked the detection of magnetic field induced changes in the peak frequency. On a much larger scale, the N latitudes showed a slightly lower value of the peak frequency as compared to the S latitudes, although the difference (25 µHz) is barely larger than the rms spread (20 µHz). 1.

P. Venkatakrishnan; Brajesh Kumar; S. C. Tripathy

2001-01-01T23:59:59.000Z

416

Measurement and Modeling of Solar and PV Output Variability  

Science Conference Proceedings (OSTI)

This paper seeks to understand what temporal and spatial scales of variability in global horizontal radiation are important to a PV plants and what measurements are needed to be able to characterize them. As solar radiation measuring instruments are point receivers it is important to understand how those measurements translate to energy received over a larger spatial extent. Also of importance is the temporal natural of variability over large spatial areas. In this research we use high temporal and spatial resolution measurements from multiple sensors at a site in Hawaii to create solar radiation fields at various spatial and temporal scales. Five interpolation schemes were considered and the high resolution solar fields were converted to power production for a PV power plant. It was found that the interpolation schemes are robust and create ramp distributions close to what would be computed if the average solar radiation field was used. We also investigated the possibility of using time averaged solar data from 1 sensor to recreate the ramp distribution from the 17 sensors. It was found that the ramping distribution from using appropriately time averaged data from 1 sensor can reasonably match the distribution created using the 17 sensor network.

Sengupta, M.

2011-01-01T23:59:59.000Z

417

Continuous variable entanglement distillation of Non-Gaussian Mixed States  

E-Print Network (OSTI)

Many different quantum information communication protocols such as teleportation, dense coding and entanglement based quantum key distribution are based on the faithful transmission of entanglement between distant location in an optical network. The distribution of entanglement in such a network is however hampered by loss and noise that is inherent in all practical quantum channels. Thus, to enable faithful transmission one must resort to the protocol of entanglement distillation. In this paper we present a detailed theoretical analysis and an experimental realization of continuous variable entanglement distillation in a channel that is inflicted by different kinds of non-Gaussian noise. The continuous variable entangled states are generated by exploiting the third order non-linearity in optical fibers, and the states are sent through a free-space laboratory channel in which the losses are altered to simulate a free-space atmospheric channel with varying losses. We use linear optical components, homodyne measurements and classical communication to distill the entanglement, and we find that by using this method the entanglement can be probabilistically increased for some specific non-Gaussian noise channels.

Ruifang Dong; Mikael Lassen; Joel Heersink; Christoph Marquardt; Radim Filip; Gerd Leuchs; Ulrik L. Andersen

2010-02-01T23:59:59.000Z

418

Decadal Climate Variability in the North Pacific during the Recent Decades  

Science Conference Proceedings (OSTI)

Decadal wintertime variability in the North Pacific climate system observed over the last few decades is documented. The decadal sea surface temperature (SST) variability is found to be concentrated around two major oceanic fronts. The ...

H. Nakamura; G. Lin; T. Yamagata

1997-10-01T23:59:59.000Z

419

Time Series Photometry of Variable Stars in the Globular Cluster NGC 6397  

E-Print Network (OSTI)

Time series BVI photometry is presented for 16 short-period variables located in the central region of the globular cluster NGC 6397. The sample includes 9 newly detected variables. The light curve of cataclysmic variable CV6 shows variability with a period of 0.2356 days. We confirm an earlier reported period of 0.472 days for cataclysmic variable CV1. Phased light curves of both CVs exhibit sine-like light curves, with two minima occurring during each orbital cycle. The secondary component of CV1 has a low average density of 0.83 g/cm^{3} indicating that it cannot be a normal main sequence star. Variables among the cluster blue stragglers include a likely detached eclipsing binary with orbital period of 0.787 days, three new SX Phe stars (one of which has the extremely short period of 0.0215 days), and three low amplitude variables which are possible gamma Doradus variables.

Janusz Kaluzny; Ian B. Thompson

2002-10-29T23:59:59.000Z

420

Rainfall Variability at Decadal and Longer Time Scales: Signal or Noise?  

Science Conference Proceedings (OSTI)

Rainfall variability occurs over a wide range of temporal scales. Knowledge and understanding of such variability can lead to improved risk management practices in agricultural and other industries. Analyses of temporal patterns in 100 yr of ...

Holger Meinke; Peter deVoil; Graeme L. Hammer; Scott Power; Robert Allan; Roger C. Stone; Chris Folland; Andries Potgieter

2005-01-01T23:59:59.000Z

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


421

The South Pacific Meridional Mode: A Mechanism for ENSO-like Variability  

Science Conference Proceedings (OSTI)

In this study we investigate the connection between the South Pacific atmospheric variability and the tropical Pacific climate in models of different degrees of coupling between atmosphere and ocean. A robust mode of variability, defined as the ...

Honghai Zhang; Amy Clement; Pedro Di Nezio

422

Variability in Large-Scale Water Balance with Land Surface-Atmosphere Interaction  

Science Conference Proceedings (OSTI)

Persistent and prolonged periods of dry or moist conditions are often evident in the interannual variability of continental-type climates This variability appears as fluctuations around several distinct and preferred moisture states. These ...

Dara Entekhabi; Ignacio Rodriguez-Iturbe; Rafael L. Bras

1992-08-01T23:59:59.000Z

423

Local-Scale Variability of Daily Solar Radiation—San Diego County, California  

Science Conference Proceedings (OSTI)

The spatial variability of daily solar radiation values over a region of several hundred square kilometers was examined. Coefficients of variability were obtained as the standard deviations of between-station daily radiation difference divided by ...

Edward Aguado

1986-05-01T23:59:59.000Z

424

Interannual Tasmanian Rainfall Variability Associated with Large-Scale Climate Modes  

Science Conference Proceedings (OSTI)

Interannual rainfall variability over Tasmania is examined using observations and reanalysis data. Tasmanian rainfall is dominated by an east–west gradient of mean rainfall and variability. The Pacific–South American mode (PSA), El Nińo–Southern ...

Khalia J. Hill; Agus Santoso; Matthew H. England

2009-08-01T23:59:59.000Z

425

Modes of Interannual Variability of the Southern Hemisphere Circulation Simulated by the CSIRO Climate Model  

Science Conference Proceedings (OSTI)

This study examines the capability of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) climate model in simulating the observed modes of interannual variability of the Southern Hemisphere circulation. Modes of variability ...

Wenju Cai; Ian G. Watterson

2002-05-01T23:59:59.000Z

426

Observed Decadal North Atlantic Tripole SST Variability. Part I: Weather Noise Forcing and Coupled Response  

Science Conference Proceedings (OSTI)

The mechanisms responsible for the decadal variability of the tripole mode of North Atlantic SST during the latter half of the twentieth century are diagnosed using a new technique. The SST and associated ocean variability are reconstructed by ...

Meizhu Fan; Edwin K. Schneider

2012-01-01T23:59:59.000Z

427

Orographic Influences on the Distribution and Generation of Atmospheric Variability in a GCM  

Science Conference Proceedings (OSTI)

The effect of large-scale mountains on atmospheric variability is studied in a series of GCM experiments in which a single mountain is varied in height from 0 to 4 km. High-frequency (? 30 days) variability are ...

Jin-Yi Yu; Dennis L. Hartmann

1995-07-01T23:59:59.000Z

428

Interannual Variability of the Upper Ocean in the Southeast Pacific Stratus Cloud Region  

Science Conference Proceedings (OSTI)

Persistent stratus/stratocumulus cloud decks in the southeast Pacific near the coasts of Peru and northern Chile play an important role in regional and global climate variability. Interannual variability of the upper ocean under stratus cloud ...

Toshiaki Shinoda; Jialin Lin

2009-10-01T23:59:59.000Z

429

1980–2010 Variability in U.K. Surface Wind Climate  

Science Conference Proceedings (OSTI)

The climate of the northeast Atlantic region comprises substantial decadal variability in storminess. It also exhibits strong inter- and intra-annual variability in extreme high and low wind speed episodes. Here the authors quantify and discuss ...

Nick Earl; Steve Dorling; Richard Hewston; Roland von Glasow

2013-02-01T23:59:59.000Z

430

Tropical climate variability from the last glacial maximum to the present  

E-Print Network (OSTI)

This thesis evaluates the nature and magnitude of tropical climate variability from the Last Glacial Maximum to the present. The temporal variability of two specific tropical climate phenomena is examined. The first is the ...

Dahl, Kristina Ariel

2005-01-01T23:59:59.000Z

431

Variability in Skill in 120 h FNOC 500 mb Height Forecasts  

Science Conference Proceedings (OSTI)

The variability of the 120 h 500 mb height forecasts of the Navy's Operational global model was examined for two winters. The forecasts displayed evidence of marked variability in the quality of forecasts as measured by anomaly correlations ...

J. Curtis; J. S. Boyle; C. H. Wash

1988-06-01T23:59:59.000Z

432

Mechanisms for Precipitation Variability of the Eastern Brazil/SACZ Convective Margin  

Science Conference Proceedings (OSTI)

The present study examines the mechanisms for the connection between the precipitation variability in eastern Brazil and the South Atlantic convergence zone (SACZ) convective margin (eastern Brazil/SACZ convective margin) and the variability of ...

H.-Y. Ma; X. Ji; J. D. Neelin; C. R. Mechoso

2011-07-01T23:59:59.000Z

433

Global Characteristics of Ocean Variability Estimated from Regional TOPEX/POSEIDON Altimeter Measurements  

Science Conference Proceedings (OSTI)

Three years of altimetric data from the TOPEX/POSEIDON spacecraft have been used to study characteristics of eddy variability over the World Ocean. The nature of the variability and its spatial structure are characterized in terms of the ...

Detlef Stammer

1997-08-01T23:59:59.000Z

434

Impact of Northward-Propagating Intraseasonal Variability on the Onset of Indian Summer Monsoon  

Science Conference Proceedings (OSTI)

The onset of Indian summer monsoon (ISM) has a pronounced interannual variability, part of which originates from the large-scale circulation and its thermodynamic properties. While the northward-propagating intraseasonal variabilities (ISVs) are a ...

Lei Zhou; Raghu Murtugudde

435

Systematic Biases in the Microphysics and Thermodynamics of Numerical Models That Ignore Subgrid-Scale Variability  

Science Conference Proceedings (OSTI)

A grid box in a numerical model that ignores subgrid variability has biases in certain microphysical and thermodynamic quantities relative to the values that would be obtained if subgrid-scale variability were taken into account. The biases are ...

Vincent E. Larson; Robert Wood; Paul R. Field; Jean-Christophe Golaz; Thomas H. Vonder Haar; William R. Cotton

2001-05-01T23:59:59.000Z

436

An Experimental Study of Small-Scale Variability of Radar Reflectivity Using Disdrometer Observations  

Science Conference Proceedings (OSTI)

Analysis of data collected by four disdrometers deployed in a 1-km2 area is presented with the intent of quantifying the spatial variability of radar reflectivity at small spatial scales. Spatial variability of radar reflectivity within the radar ...

Benjamin J. Miriovsky; A. Allen Bradley; William E. Eichinger; Witold F. Krajewski; Anton Kruger; Brian R. Nelson; Jean-Dominique Creutin; Jean-Marc Lapetite; Gyu Won Lee; Isztar Zawadzki; Fred L. Ogden

2004-01-01T23:59:59.000Z

437

Analysis Methods for Characterizing Salinity Variability from Multivariate Time Series Applied to the Apalachicola Bay Estuary  

Science Conference Proceedings (OSTI)

Statistical analysis methods are developed to quantify the impacts of multiple forcing variables on the hydrographic variability within an estuary instrumented with an enduring observational system. The methods are applied to characterize the ...

Steven L. Morey; Dmitry S. Dukhovskoy

2012-04-01T23:59:59.000Z

438

Gage Density and Variability of Rainfall Estimates: A Complement to Silverman, Rogers and Dahl's Study  

Science Conference Proceedings (OSTI)

As a complement to the study by Silverman et al, (1981, this issue), the relative variability of rainfall estimates was studied for randomly located gages. This simplistic model allows for more random variability than Silverman et al.'s model ...

K. R. Gabriel

1981-12-01T23:59:59.000Z

439

Examining Internal and External Contributors to Greenland Climate Variability Using CCSM3  

Science Conference Proceedings (OSTI)

Greenland climate variability is connected to internal and external sources of global climate variability in six millennium simulations using Community Climate System Model 3. Simulation forcings are consistent with the PaleoClimate Model Inter-...

Heather J. Andres; W. R. Peltier

440

Influence of South Atlantic Sea Surface Temperatures on Rainfall Variability and Extremes over Southern Africa  

Science Conference Proceedings (OSTI)

It is generally agreed that changing climate variability, and the associated change in climate extremes, may have a greater impact on environmentally vulnerable regions than a changing mean. This research investigates rainfall variability, ...

C. J. R. Williams; D. R. Kniveton; R. Layberry

2008-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Reconstructing the NH Mean Temperature: Can Underestimation of Trends and Variability Be Avoided?  

Science Conference Proceedings (OSTI)

There are indications that hemispheric-mean climate reconstructions seriously underestimate the amplitude of low-frequency variability and trends. Some of the theory of linear regression and error-in-variables models is reviewed to identify the ...

Bo Christiansen

2011-02-01T23:59:59.000Z

442

A Variable-Resolution Stretched-Grid General Circulation Model: Regional Climate Simulation  

Science Conference Proceedings (OSTI)

The development of and results obtained with a variable-resolution stretched-grid GCM for the regional climate simulation mode are presented. A global variable-resolution stretched grid used in the study has enhanced horizontal resolution over ...

Michael S. Fox-Rabinovitz; Lawrence L. Takacs; Ravi C. Govindaraju; Max J. Suarez

2001-03-01T23:59:59.000Z

443

Simulations of the Eastern North Pacific Intraseasonal Variability in CMIP5 GCMs  

Science Conference Proceedings (OSTI)

As a key component of tropical atmospheric variability, intraseasonal variability (ISV) over the eastern North Pacific Ocean (ENP) exerts pronounced influences on regional weather and climate. Since general circulation models (GCMs) are essential ...

Xianan Jiang; Eric D. Maloney; Jui-Lin F. Li; Duane E. Waliser

2013-06-01T23:59:59.000Z

444

Submonthly Polar Vortex Variability and Stratosphere–Troposphere Coupling in the Arctic  

Science Conference Proceedings (OSTI)

A principal component analysis is performed to characterize intraseasonal variability in the boreal stratospheric polar vortex. In contrast to previous studies, the current analysis examines daily zonal-mean variability within a limited spatial ...

Robert X. Black; Brent A. McDaniel

2009-11-01T23:59:59.000Z

445

Characterizing the Variability and Extremes of the Stratospheric Polar Vortices Using 2D Moment Analysis  

Science Conference Proceedings (OSTI)

The mean state, variability, and extreme variability of the stratospheric polar vortices, with an emphasis on the Northern Hemisphere (NH) vortex, are examined using two-dimensional moment analysis and extreme value theory (EVT). The use of ...

Daniel M. Mitchell; Andrew J. Charlton-Perez; Lesley J. Gray

2011-06-01T23:59:59.000Z

446

Mixed Variable Optimization of the Number and Composition of Heat Intercepts in a Thermal Insulation System  

E-Print Network (OSTI)

: In the literature, thermal insulation systems with a xed number of heat intercepts have been optimized with respect to intercept locations and temperatures. The number of intercepts and the types of insulators that surround them were chosen by parametric studies. This was because the optimization methods used could not treat such categorical variables. Discrete optimization variables are categorical if the objective function or the constraints can not be evaluated unless the variables take one of a prescribed enumerable set of values. The key issue is that categorical variables can not be treated as ordinary discrete variables are treated by relaxing them to continuous variables with a side constraint that they be discrete at the solution. A new mixed variable programming (MVP) algorithm makes it possible to optimize directly with respect to mixtures of discrete, continuous, and categorical decision variables. The result of applying MVP is shown here to give a 65% reduction in the ...

Michael Kokkolaras; Charless Audet; J. E. Dennis, Jr.

2000-01-01T23:59:59.000Z

447

Decadal Variability in an Idealized Ocean Model and Its Sensitivity to Surface Boundary Conditions  

Science Conference Proceedings (OSTI)

Variability in a three-dimensional ocean model of idealized geometry is analyzed. The variability is induced in the model by adding a stochastic component to the surface buoyancy forcing. The influence of the surface thermal forcing on the model ...

A. Capotondi; W. R. Holland

1997-06-01T23:59:59.000Z

448

ESP-The Electrical submersible pump. Part 7. Applying variable frequency drives to ESPs  

SciTech Connect

To keep pace with technology, the oil industry has begun using variable frequency drives on electrical submersible pumps. Applying variable frequency drives on ESPs began seriously in 1977. In March 1983, there were approximately 350 variable frequency drives successfully operating on electrical submersible pumps throughout the world. Three types of variable frequency drives available today are the current source inverter, the pulse width modulation, and the variable voltage source inverter. As all three types have good points and bad, a short discussion of each type is essential to understand why the variable voltage inverter is used most often in oil field applications and why it has been a success. A current source inverter typically uses a phasecontrolled rectifier to generate variable DC current. The phase-controlled rectifier produces the required current which is subsequently filtered by a DC link reactor. The inverter then produces the desired variable frequency current and the motor voltage varies with load.

Watson, A.J.

1983-11-15T23:59:59.000Z

449

North Atlantic Decadal Variability: Air–Sea Coupling, Oceanic Memory, and Potential Northern Hemisphere Resonance  

Science Conference Proceedings (OSTI)

In this paper, the causes and mechanisms of North Atlantic decadal variability are explored in a series of coupled ocean–atmosphere simulations. The model captures the major features of the observed North Atlantic decadal variability. The North ...

Lixin Wu; Zhengyu Liu

2005-01-01T23:59:59.000Z

450

Seasonal Hydroclimate Variability over North America in Global and Regional Reanalyses and AMIP Simulations: Varied Representation  

Science Conference Proceedings (OSTI)

The monotony of seasonal variability is often compensated by the complexity of its spatial structure—the case in North American hydroclimate. The structure of hydroclimate variability is analyzed to provide insights into the functioning of the ...

Sumant Nigam; Alfredo Ruiz-Barradas

2006-03-01T23:59:59.000Z

451

Effects of Weather Variables on Pedestrian Volumes in Alameda County, California  

E-Print Network (OSTI)

within 1/4?mile  Weather  Average hourly solar radiation 2 weather stations. Air temperature, precipitation, solarWeather Variables Binary dummy variables were used to capture possible non-linear effects of temperature, wind speed, solar

Attaset, Vanvisa; Schneider, Robert J.; Arnold, Lindsay S.; Ragland, David R

2010-01-01T23:59:59.000Z

452

The MACHO Project LMC Variable Star Inventory Classical Cepheids, AGB Variables, and the 9 Million Star Color-Magnitude Diagram  

E-Print Network (OSTI)

We measure the ratio of ~5 M_solar blue and red LMC supergiants (representative of classical Cepheids) using the MACHO Project's 9 million star color-magnitude diagram (9M CMD) of the LMC bar. We find b/r = 0.39, which favors the z=0.008, 5 M_solar theoretical model of Schaerer et al.(1993) over that of Fagatto et al. (1994). Next, we examine the low mass (old) and low metallicity LMC field population (Pop. II). Features in the 9M CMD and properties of LMC field RRab are consistent with a mean iron abundance of [Fe/H] = -1.5 dex for this population. Newly discovered post-HB/early-AGB Pop. II variables are identified in order to delineate the instability strip (IS). Good agreement with the theoretical IS of Bono et al. (1997) is found. We then compare the field RRab with newly identified RRab variables in the LMC clusters NGC 1898 and NGC 1835. We find the mean colors of these cluster RRab lie near the red and blue edges of the IS, respectively, which is similar to their respective (overall) red and blue HB mo...

Alves, D R; Cook, K H; Welch, D L; Alcock, C B; Marshall, S; Axelrod, T S; Drake, A; Freeman, K C; Peterson, B M; Allsman, R A; Becker, A; Tomaney, A B; Griest, K; Vandehei, T; Lehner, M; Bennett, D; Minniti, D; Pratt, M; Sutherland, W; Quinn, P

1998-01-01T23:59:59.000Z

453

Variability of Gas Composition and Flux Intensity in Natural Marine Hydrocarbon Seeps  

E-Print Network (OSTI)

Energy Development and Technology 008 "Variability of gas composition and flux intensity in natural marine hydrocarbon seeps" Jordan

Clark, J F; Schwager, Katherine; Washburn, Libe

2005-01-01T23:59:59.000Z

454

Natural Gas Variability In California: Environmental Impacts And Device  

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

Natural Gas Variability In California: Environmental Impacts And Device Natural Gas Variability In California: Environmental Impacts And Device Performance - Experimental Evaluation Of Installed Cooking Exhaust Fan Performance Title Natural Gas Variability In California: Environmental Impacts And Device Performance - Experimental Evaluation Of Installed Cooking Exhaust Fan Performance Publication Type Report Year of Publication 2011 Authors Singer, Brett C., William W. Delp, and Michael G. Apte Publisher Lawrence Berkeley National Laboratory City Berkeley, CA Keywords energy analysis and environmental impacts department Abstract The installed performance of cooking exhaust fans was evaluated through residential field experiments conducted on a sample of 15 devices varying in design and other characteristics. The sample included two rear downdraft systems, two under-cabinet microwave over range units, three different installations of an under-cabinet model with grease screens across the bottom and no capture hood, two devices with grease screens covering the bottom of a large capture hood (one under-cabinet, one wall-mount chimney), four under-cabinet open hoods, and two open hoods with chimney mounts over islands. Performance assessment included measurement of airflow and sound levels across fan settings and experiments to quantify the contemporaneous capture efficiency for the exhaust generated by natural gas cooking burners. Capture efficiency is defined as the fraction of generated pollutants that are removed through the exhaust and thus not available for inhalation of household occupants. Capture efficiency was assessed for various configurations of burner use (e.g., single front, single back, combination of one front and one back, oven) and fan speed setting. Measured airflow rates were substantially lower than the levels noted in product literature for many of the units. This shortfall was observed for several units costing more than $1000. Capture efficiency varied widely (from < 5 percent to roughly 100 percent) across devices and across conditions for some devices. As expected, higher capture efficiencies were achieved with higher fan settings and the associated higher air flow rates. In most cases, capture efficiencies were substantially higher for rear burners than for front burners. The best and most consistent performance was observed for open hoods that covered all cooktop burners and operated at higher airflow rates. The lowest capture efficiencies were measured when a front burner was used with a rear backdraft system or with lowest fan setting for above-the-range systems that do not cover the front burners.

455

Systematic Variability of Soil Hydraulic Conductivity Across Three Vertisol Catenas  

E-Print Network (OSTI)

Soil hydraulic properties, such as saturated hydraulic conductivity (Ks), have high spatial variation, but little is known about how to vary a few measurements of Ks over an area to model hydrology in a watershed with complex topography and multiple land uses. Variations in soil structure, macropores (especially in soil that shrink and swell), land use, and soil development can cause large variations in Ks within one soil type. Characterizing the impacts of soil properties that might vary systematically with land use and terrain attributes on Ks rates would provide insight on how management and human activity affect local and regional hydrology. The overall objective of this research was to develop a strategy for using published infiltration and Ks measurements by the Natural Resources Conservation Service for watershed hydrology applications in a Vertisol, and to extend this knowledge toward developing recommendations for future infiltration measurements. To achieve this goal, soil infiltration measurements were collected across three catenas of Houston Black and Heiden clays (fine, smectitic, thermic Udic Haplusterts) under three land uses (improved pasture, native prairie, and conventional tillage row crop). Measurement locations were selected to account for variation in terrain attributes. Overall, Ks values were not significantly different across different landscape positions; however, in fields under similar land uses, Ks values were found to be lower in the footslope positions and higher in the backslope positions. The pedotransfer function, ROSETTA, provided estimates of 64 percent of the overall variability in Ks while also providing accurate estimates of the mean of Ks when particle size distribution and bulk density are used as inputs in the model. Through the use of multiple regression analysis, soil antecedent water content, bulk density, clay content, and soil organic carbon along with two indicator variables for the catenas were highly correlated (r2 = 0.59) with Ks. The indicator variables explained 17 percent of the variation in Ks that could not be explained by measured soil properties. It is recommended that when NRCS measures Ks on benchmark soils, especially high clay soils, that they collect particle size distribution, bulk density, organic carbon, and antecedent water content data.

Rivera, Leonardo Daniel

2010-08-01T23:59:59.000Z

456

Quantification of Variability and Uncertainty in Hourly NOx Emissions from Coal-Fired Power Plants  

E-Print Network (OSTI)

1 Quantification of Variability and Uncertainty in Hourly NOx Emissions from Coal-Fired Power to quantify variability and uncertainty for NOx emissions from coal-fired power plants. Data for hourly NOx Uncertainty, Variability, Emission Factors, Coal-Fired Power Plants, NOx emissions, Regression Models

Frey, H. Christopher

457

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

LBNL-58636 Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable Efficient Cleanrooms Efficient HVAC Water Systems: Variable-Speed-Drive Chillers Tengfang Xu Contents HVAC.................................................................................................................................... 6 #12;HVAC Water Systems Variable-Speed-Drive Chillers Summary Cleanroom energy benchmarking data

458

Intraseasonal Variability of the West African Monsoon and Atlantic ITCZ ERIC D. MALONEY AND JEFFREY SHAMAN  

E-Print Network (OSTI)

Intraseasonal Variability of the West African Monsoon and Atlantic ITCZ ERIC D. MALONEY AND JEFFREY amplitude of the 30­90-day West African monsoon precipitation variability during a given summer, however and Grist 2003; Redelsperger et al. 2006). Intraseasonal variability of the West African monsoon has

Shaman, Jeffrey

459

A neural network control strategy for improved energy capture on a variable-speed wind turbine  

Science Conference Proceedings (OSTI)

Pitch control has so far been the dominating method for power control in modern variable speed wind turbines. This paper proposes an improved control technique for pitching the blades of a variable speed wind turbine, using Artificial Neural Networks ... Keywords: artificial neural networks, control trajectories, pitch control, variable-speed wind turbines

António F. Silva; Fernando A. Castro; José N. Fidalgo

2005-06-01T23:59:59.000Z

460

Choosing the best set of variables in regression analysis using integer programming  

Science Conference Proceedings (OSTI)

This paper is concerned with an algorithm for selecting the best set of s variables out of k(> s) candidate variables in a multiple linear regression model. We employ absolute deviation as the measure of deviation and solve ... Keywords: 0-1 integer programming, Cardinality constraint, Least absolute deviation, Linear regression, Variable selection

Hiroshi Konno; Rei Yamamoto

2009-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

Intrinsic intraday variability in the gravitational lens system B0218+357  

E-Print Network (OSTI)

Radio monitoring of the gravitational lens system B0218+357 reveals it to be a highly variable source with variations on timescales of a few days correlated in both images. This shows that the variability is intrinsic to the background lensed source and suggests that similar variations in other intraday variable sources can also be intrinsic in origin.

A. D. Biggs; I. W. A. Browne; P. N. Wilkinson

2000-12-22T23:59:59.000Z

462

Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture  

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

Hydrogen-Assisted Fracture: Materials Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Brian Somerday, Chris San Marchi, and Dorian Balch Sandia National Laboratories Livermore, CA Hydrogen Pipeline Working Group Workshop Augusta, GA August 30-31, 2005 SNL has 40+ years experience with effects of high-pressure hydrogen gas on materials * Design and maintenance of welded stainless steel pressure vessels for containment of high-pressure H 2 isotopes - Extensive testing of stainless steels exposed to high-pressure H 2 gas * Six-year program in 1970s focused on feasibility of using natural gas pipeline network for H 2 gas - Materials testing in high-pressure H 2 gas using laboratory specimens and model pipeline - Examined fusion zone and heat affected zones of welds * Active SNL staff have authored 70+ papers and organized 6

463

Demand Response and Variable Generation Integration Scoping Study  

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

Market and Policy Barriers for Demand Market and Policy Barriers for Demand Response Providing Ancillary Services in U.S. Electricity Markets Peter Cappers, Jason MacDonald, Charles Goldman April 2013 Report Summary 1 Energy Analysis Department  Electricity Markets and Policy Group Presentation Overview  Objectives and Approach  Wholesale and Retail Market Environments  Market and Policy Barrier Typology  Prototypical Regional Barrier Assessment 2 Energy Analysis Department  Electricity Markets and Policy Group A Role for Demand Response to Provide Ancillary Services  Increasing penetration of renewable energy generation in U.S. electricity markets means that bulk power system operators will need to manage the variable and uncertain nature of many renewable resources

464

Method and apparatus for calibrating a linear variable differential transformer  

DOE Patents (OSTI)

A calibration apparatus for calibrating a linear variable differential transformer (LVDT) having an armature positioned in au LVDT armature orifice, and the armature able to move along an axis of movement. The calibration apparatus includes a heating mechanism with an internal chamber, a temperature measuring mechanism for measuring the temperature of the LVDT, a fixture mechanism with an internal chamber for at least partially accepting the LVDT and for securing the LVDT within the heating mechanism internal chamber, a moving mechanism for moving the armature, a position measurement mechanism for measuring the position of the armature, and an output voltage measurement mechanism. A method for calibrating an LVDT, including the steps of: powering the LVDT; heating the LVDT to a desired temperature; measuring the position of the armature with respect to the armature orifice; and measuring the output voltage of the LVDT.

Pokrywka, Robert J. (North Huntingdon, PA)

2005-01-18T23:59:59.000Z

465

Systematic Controller Design Methodology for Variable-Speed Wind Turbines  

DOE Green Energy (OSTI)

Variable-speed, horizontal axis wind turbines use blade-pitch control to meet specified objectives for three operational regions. This paper provides a guide for controller design for the constant power production regime. A simple, rigid, non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired. The robust nature of the proportional-integral-derivative controller is illustrated, and optimal operating conditions are determined. Because numerous simulation runs may be completed in a short time, the relationship between the two opposing metrics is easily visualized.

Hand, M. M.; Balas, M. J.

2002-02-01T23:59:59.000Z

466

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,

467

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

468

MASe UCRL-15037 CONTINUOUSLY VARIABLE TRANSMISSIONS: THEORY AND PRACTICE  

Office of Scientific and Technical Information (OSTI)

^ . S7l MASe UCRL-15037 CONTINUOUSLY VARIABLE TRANSMISSIONS: THEORY AND PRACTICE August 1979 Norman H. Beachley Andrew A. Frank College of Engineering University of Wisconsin, Madison n LAWRENCE UVERMORE LABORATORY vmrnm IP T H I S 8ocu«arr ii mmm NOTICE 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, or any of their employees, makes any warranty, expressed or implied, or assumes any legal Uability or responsibility for any third party's use, or the results of such use, of any information, ap- paratus, product or process disclosed in this report, or represents that its use by such third party would not infringe privately owned rights.

469

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

470

Observational Constraints of New Variable Modified Chaplygin Gas Model  

E-Print Network (OSTI)

Assuming the flat FRW universe in Einstein's gravity filled with New Variable Modified Chaplygin gas (NVMCG) dark energy and dark matter having negligible pressure. In this research work we analyze the viability on the basis of recent observation. Hubble parameter $H$ is expressed in terms of the observable parameters $H_0$, $\\Omega_m^0$ and the model parameters $A_0$, $B_0$, $C_0$, $m$, $n$, $\\alpha$ and the red shift parameter $z$. Here we find a best fitted parameter range of $A_0$, $B_0$ keeping $0\\leq \\alpha \\leq 1$ and using Stern data set (12 points) by minimizing the $\\chi^2$ test at 66%, 90% and 99% confidence levels. Next we do the joint analysis with BAO and CMB observations. Again evaluating the distance modulus $\\mu(z)$ vs redshift ($z$) curve obtained in the model NVMCG with dark matter with the best fitted value of the parameters and comparing with that derived from the union2 compilation data.

Jhumpa Bhadra; Ujjal Debnath

2012-11-09T23:59:59.000Z

471

Variable speed constant frequency constant voltage alternator. Annual report  

DOE Green Energy (OSTI)

A test alternator is operated with digital control of its output frequency for variable shaft speed. The machine is a two-pole alternator with power removed through slip rings. The output frequency of the alternator is controlled by rotating the field by stepping through sixteen coils around the rotor. Usually four coils are active at one time. The rotating field in the stationary coils of the stator is controlled by microcircuits. The control circuits are constructed with available low-cost, low-power integrated circuits (ICs). The test results from the first test alternator indicate the feasibility of using this type of alternator to convert available wind power directly to usable 60 hertz power.

Grannemann, W.W.; Yang, C.E.; Seo, P.H.

1980-07-01T23:59:59.000Z

472

Entanglement, Purity, and Information Entropies in Continuous Variable Systems  

E-Print Network (OSTI)

Quantum entanglement of pure states of a bipartite system is defined as the amount of local or marginal ({\\em i.e.}referring to the subsystems) entropy. For mixed states this identification vanishes, since the global loss of information about the state makes it impossible to distinguish between quantum and classical correlations. Here we show how the joint knowledge of the global and marginal degrees of information of a quantum state, quantified by the purities or in general by information entropies, provides an accurate characterization of its entanglement. In particular, for Gaussian states of continuous variable systems, we classify the entanglement of two--mode states according to their degree of total and partial mixedness, comparing the different roles played by the purity and the generalized $p-$entropies in quantifying the mixedness and bounding the entanglement. We prove the existence of strict upper and lower bounds on the entanglement and the existence of extremally (maximally and minimally) entang...

Adesso, G; Illuminati, F; Adesso, Gerardo; Serafini, Alessio; Illuminati, Fabrizio

2005-01-01T23:59:59.000Z

473

A discrete variable representation for electron-hydrogen atom scattering  

DOE Green Energy (OSTI)

A discrete variable representation (DVR) suitable for treating the quantum scattering of a low energy electron from a hydrogen atom is presented. The benefits of DVR techniques (e.g. the removal of the requirement of calculating multidimensional potential energy matrix elements and the availability of iterative sparse matrix diagonalization/inversion algorithms) have for many years been applied successfully to studies of quantum molecular scattering. Unfortunately, the presence of a Coulomb singularity at the electrically unshielded center of a hydrogen atom requires high radial grid point densities in this region of the scattering coordinate, while the presence of finite kinetic energy in the asymptotic scattering electron also requires a sufficiently large radial grid point density at moderate distances from the nucleus. The constraints imposed by these two length scales have made application of current DVR methods to this scattering event difficult.

Gaucher, L.F.

1994-08-01T23:59:59.000Z

474

VARIABLE MODERATOR REACTOR DEVELOPMENT PROGRAM. Quarterly Progress Report No. 1  

SciTech Connect

Development of the boiling water UO/sub 2/ fueled Variable Moderator Reactor (VMR) is conducted under contract for the USAEC. The initiation and progress of work under Phase I of the contract, Physics and Kinetic Analysis and Initial Evaluation,'' and the preparation for Phase II, Critical Experiment and Analysis of Results,'' are reported. A hydrodynamic flow sheet representing the sequence of calculations for the BOCH program was prepared. A preliminary block diagram of the kinetics model of the VMR was prepared. Work is reported on the PUREE code which is designed to give an accurate representation of the physics of the VMR core. A fuel element fabrication speciftcation was prepared and released for quotations. A study was made to select the most appropriate material for void simulation throughout the range of interest in the VMR. (W.D.M.)

1959-08-31T23:59:59.000Z

475

Method and Appartus for Calibrating a Linear Variable Differential Transformer  

DOE Patents (OSTI)

A calibration apparatus for calibrating a linear variable differential transformer (LVDT) having an armature positioned in au LVDT armature orifice, and the armature able to move along an axis of movement. The calibration apparatus includes a heating mechanism with an internal chamber, a temperature measuring mechanism for measuring the temperature of the LVDT, a fixture mechanism with an internal chamber for at least partially accepting the LVDT and for securing the LVDT within the heating mechanism internal chamber, a moving mechanism for moving the armature, a position measurement mechanism for measuring the position of the armature, and an output voltage measurement mechanism. A method for calibrating an LVDT, including the steps of powering the LVDT; heating the LVDT to a desired temperature; measuring the position of the armature with respect to the armature orifice; and measuring the output voltage of the LVDT.

Pokrywka, Robert J.

2005-01-18T23:59:59.000Z

476

Non-Gaussian entanglement distillation for continuous variables  

E-Print Network (OSTI)

Entanglement distillation is an essential ingredient for long distance quantum communications. In the continuous variable setting, Gaussian states play major roles in quantum teleportation, quantum cloning and quantum cryptography. However, entanglement distillation from Gaussian states has not yet been demonstrated. It is made difficult by the no-go theorem stating that no Gaussian operation can distill Gaussian states. Here we demonstrate the entanglement distillation from Gaussian states by using measurement-induced non-Gaussian operations, circumventing the fundamental restriction of the no-go theorem. We observed a gain of entanglement as a result of conditional local subtraction of a single photon or two photons from a two-mode Gaussian state. Furthermore we confirmed that two-photon subtraction also improves Gaussian-like entanglement as specified by the Einstein-Podolsky-Rosen (EPR) correlation. This distilled entanglement can be further employed to downstream applications such as high fidelity quantum teleportation and a loophole-free Bell test.

Hiroki Takahashi; Jonas S. Neergaard-Nielsen; Makoto Takeuchi; Masahiro Takeoka; Kazuhiro Hayasaka; Akira Furusawa; Masahide Sasaki

2009-07-13T23:59:59.000Z

477

Performance of twist-coupled blades on variable speed rotors  

DOE Green Energy (OSTI)

The load mitigation and energy capture characteristics of twist-coupled HAWT blades that are mounted on a variable speed rotor are investigated in this paper. These blades are designed to twist toward feather as they bend with pretwist set to achieve a desirable twist distribution at rated power. For this investigation, the ADAMS-WT software has been modified to include blade models with bending-twist coupling. Using twist-coupled and uncoupled models, the ADAMS software is exercised for steady wind environments to generate C{sub p} curves at a number of operating speeds to compare the efficiencies of the two models. The ADAMS software is also used to generate the response of a twist-coupled variable speed rotor to a spectrum of stochastic wind time series. This spectrum contains time series with two mean wind speeds at two turbulence levels. Power control is achieved by imposing a reactive torque on the low speed shaft proportional to the RPM squared with the coefficient specified so that the rotor operates at peak efficiency in the linear aerodynamic range, and by limiting the maximum RPM to take advantage of the stall controlled nature of the rotor. Fatigue calculations are done for the generated load histories using a range of material exponents that represent materials from welded steel to aluminum to composites, and results are compared with the damage computed for the rotor without twist-coupling. Results indicate that significant reductions in damage are achieved across the spectrum of applied wind loading without any degradation in power production.

Lobitz, D.W.; Veers, P.S.; Laino, D.J.

1999-12-07T23:59:59.000Z

478

Assessing Corn Stover Composition and Sources of Variability via NIRS  

Science Conference Proceedings (OSTI)

Corn stover, the above-ground, non-grain portion of the crop, is a large, currently available source of biomass that potentially could be collected as a biofuels feedstock. Biomass conversion process economics are directly affected by the overall biochemical conversion yield, which is assumed to be proportional to the carbohydrate content of the feedstock materials used in the process. Variability in the feedstock carbohydrate levels affects the maximum theoretical biofuels yield and may influence the optimum pretreatment or saccharification conditions. The aim of this study is to assess the extent to which commercial hybrid corn stover composition varies and begin to partition the variation among genetic, environmental, or annual influences. A rapid compositional analysis method using near-infrared spectroscopy/partial least squares multivariate modeling (NIR/PLS) was used to evaluate compositional variation among 508 commercial hybrid corn stover samples collected from 47 sites in eight Corn Belt states after the 2001, 2002, and 2003 harvests. The major components of the corn stover, reported as average (standard deviation) % dry weight, whole biomass basis, were glucan 31.9 (2.0), xylan 18.9 (1.3), solubles composite 17.9 (4.1), and lignin (corrected for protein) 13.3 (1.1). We observed wide variability in the major corn stover components. Much of the variation observed in the structural components (on a whole biomass basis) is due to the large variation found in the soluble components. Analysis of variance (ANOVA) showed that the harvest year had the strongest effect on corn stover compositional variation, followed by location and then variety. The NIR/PLS rapid analysis method used here is well suited to testing large numbers of samples, as tested in this study, and will support feedstock improvement and biofuels process research.

Templeton, D. W.; Sluiter, A. D.; Hayward, T. K.; Hames, B. R.; Thomas, S. R.

2009-01-01T23:59:59.000Z

479

The Kelastic variable wall mining machine. Interim final report  

SciTech Connect

This machine cuts coal along a longwall face extending up to 500 feet by a rotating auger with bits. The machine also transports the coal that is cut acting as screw conveyor. By virtue of an integral shroud comprising part of the conveyor the machine is also amenable to a separation of the zones where men work from air being contaminated by dust and methane gas by the cutting action. Beginning as single intake air courses, the air separates at the working section where one split provides fresh air to the Occupied Zone (OZ) for human needs and the other split purges and carries away dust and methane from face fragmentation in the Cutting Zone (CZ). The attractiveness of the Variable Wall Mining Machine is that it addresses the limitations of current longwall mining equipment: it can consistently out-produce continuous mining machines and most longwall shearing machines. It also is amenable to configuring an environment, the dual-duct system, where the air for human breathing is separated from dust-laden ventilating air with methane mixtures. The objective of the research was to perform a mathematical and experimental study of the interrelationships of the components of the system so that a computer model could demonstrate the workings of the system in an animation program. The analysis resulted in the compilation of the parameters for three different configurations of a dual aircourse system of ventilating underground mines. In addressing the goal of an inherently safe mining system the dual-duct adaptation to the Variable Wall Mining Machine appears to offer the path to solution. The respirable dust problem is solvable; the explosive dust problem is nearly solvable; and the explosive methane problem can be greatly reduced. If installed in a highly gassy mine, the dual duct models would also be considerably less costly.

1995-11-12T23:59:59.000Z

480

Offshore operations report. ESP - the electrical submersible pump. Part 7. Applying variable frequency drives to esps  

SciTech Connect

The oil industry has begun using variable frequency drives on electric submersible pumps. In March 1983, there were approximately 350 variable frequency drives successfully operating on electrical submersible pumps throughout the world. Three types of variable frequency drives available are the current source inverter, the pulse width modulation, and the variable voltage source inverter. A short discussion of each type is given to explain why the variable voltage inverter is used most often in oil field applications and why it has been a success.

Watson, A.J.

1983-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "naire variable variable" 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

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

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

Mass Market Demand Response and Mass Market Demand Response and Mass Market Demand Response and Mass Market Demand Response and Variable Generation Integration Issues: Variable Generation Integration Issues: Variable Generation Integration Issues: Variable Generation Integration Issues: A Scoping Study A Scoping Study Peter Cappers, Andrew Mills, Charles Goldman, Ryan Wiser, Joseph H. Eto Report Summary October 2011 Energy Analysis Department  Electricity Markets and Policy Group 1 1 Presentation Overview Presentation Overview  Objectives and Approach  Variable Generation Resources and the Bulk Power System  Demand Response Opportunities  Demand Response as a Strategy to Integrate p gy g Variable Generation Resources  Comparison of Various Strategies to Integrate Variable Generation  Conclusions Energy Analysis Department  Electricity Markets and Policy Group

482

Advanced Variable Speed Air-Source Integrated Heat Pumps Research Project |  

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

Advanced Variable Speed Air-Source Advanced Variable Speed Air-Source Integrated Heat Pumps Research Project Advanced Variable Speed Air-Source Integrated Heat Pumps Research Project The U.S. Department of Energy is currently conducting research into advanced variable speed air-source integrated heat pumps (AS-IHPs). Project Description This project seeks to develop AS-IHP products for the larger air-source system market. Development focuses on a fully variable capacity or variable speed AS-IHP option. Project Partners Research is being undertaken through a cooperative research and development agreement (CRADA) between the Department of Energy, Oak Ridge National Laboratory, and a CRADA partner. Project Goals The goal of this project is the development of a fully variable-speed version of an AS-IHP product that can provide heating, ventilation, and air

483

VARIABILITY OF KD VALUES IN CEMENTITIOUS MATERIALS AND SEDIMENTS  

Science Conference Proceedings (OSTI)

Measured distribution coefficients (K{sub d} values) for environmental contaminants provide input data for performance assessments (PA) that evaluate physical and chemical phenomena for release of radionuclides from wasteforms, degradation of engineered components and subsequent transport of radionuclides through environmental media. Research efforts at SRNL to study the effects of formulation and curing variability on the physiochemical properties of the saltstone wasteform produced at the Saltstone Disposal Facility (SDF) are ongoing and provide information for the PA and Saltstone Operations. Furthermore, the range and distribution of plutonium K{sub d} values in soils is not known. Knowledge of these parameters is needed to provide guidance for stochastic modeling in the PA. Under the current SRS liquid waste processing system, supernate from F & H Tank Farm tanks is processed to remove actinides and fission products, resulting in a low-curie Decontaminated Salt Solution (DSS). At the Saltstone Production Facility (SPF), DSS is mixed with premix, comprised of blast furnace slag (BFS), Class F fly ash (FA), and portland cement (OPC) to form a grout mixture. The fresh grout is subsequently placed in SDF vaults where it cures through hydration reactions to produce saltstone, a hardened monolithic waste form. Variation in saltstone composition and cure conditions of grout can affect the saltstone's physiochemical properties. Variations in properties may originate from variables in DSS, premix, and water to premix ratio, grout mixing, placing, and curing conditions including time and temperature (Harbour et al. 2007; Harbour et al. 2009). There are no previous studies reported in the literature regarding the range and distribution of K{sub d} values in cementitious materials. Presently, the Savannah River Site (SRS) estimate ranges and distributions of K{sub d} values based on measurements of K{sub d} values made in sandy SRS sediments (Kaplan 2010). The actual cementitious material K{sub d} values and solubility values differ from the sandy sediments. The K{sub d} value range and distribution currently used in the PA are estimated to range between 0.25*K{sub d} and 1.75*K{sub d}, where the minimum and maximum values of the ranges reflect the 95% confidence level for the mean K{sub d} value (Kaplan 2010). The objective of the research with cementitious materials was to measure the range and distribution of a monovalent (Cs) and I{sup -} (anion), divalent (Sr), and trivalent (Eu) ions for a variety of laboratory-prepared saltstone surrogate samples to establish a K{sub d} range other than that which is presently used in the PA. It has been observed in laboratory samples that cure temperature profiles can affect properties such as heat of hydration, permeability, porosity, compressive strength, and set time (Harbour et al. 2009). The intent was to identify a range and distribution that could be used by stochastic modelers for the PA. Furthermore, the intent was to replace the arbitrarily selected distributions based on geological sandy sediments and to base it on actual cementitious materials. The scope of this study did not include understanding saltstone sorption mechanisms responsible for increasing or decreasing sorption. Similar to the work with cementitious materials, the purpose of the Pu sediment K{sub d} dataset was not to attempt to understand through statistics how to better understand Pu sorption to sediments or to lower Pu K{sub d} variance. The sediment Pu K{sub d} data is included in this study because it is a key risk driver for the PAs on the SRS, and there is presently no direct studies of Pu variability in SRS soils. Instead the distribution of Pu sediment K{sub d} values was assumed to be similar to other cations, as presented by Kaplan (2010).

Almond, P.; Kaplan, D.; Shine, E.

2012-02-02T23:59:59.000Z

484

A new “Variable Resolution Associative Memory” for High Energy Physics  

E-Print Network (OSTI)

We describe an important advancement for the Associative Memory device (AM). The AM is a VLSI processor for pattern recognition based on Content Addressable Memory (CAM) architecture. The AM is optimized for on-line track finding in high-energy physics experiments. Pattern matching is carried out finding track candidates in coarse resolution “roads”. A large AM bank stores all trajectories of interest, called “patterns”, for a given detector resolution. The AM extracts roads compatible with a given event during detector read-out. Two important variables characterize the quality of the AM bank: its “coverage” and the level of “found fakes”. The coverage, which describes the geometric efficiency of a bank, is defined as the fraction of tracks that match at least a pattern in the bank. Given a certain road size, the coverage of the bank can be increased just adding patterns to the bank, while the number of found fakes unfortunately is roughly proportional to this number of patterns in the bank. M...

Annovi, A; The ATLAS collaboration; Beretta, M; Bossini, E; Crescioli, F; Dell'Orso, M; Giannetti, P; Hoff, J; Liberali, V; Liu, T; Magalotti, D; Piendibene, M; Sacco, A; Schoening, A; Soltveit, H K; Stabile, A; Tripiccione, R; Vitillo, R; Volpi, G

2011-01-01T23:59:59.000Z

485

A new Variable Resolution Associative Memory for High Energy Physics  

E-Print Network (OSTI)

We describe an important advancement for the Associative Memory device (AM). The AM is a VLSI processor for pattern recognition based on Content Addressable Memory (CAM) architecture. The AM is optimized for on-line track finding in high-energy physics experiments. Pattern matching is carried out finding track candidates in coarse resolution “roads”. A large AM bank stores all trajectories of interest, called “patterns”, for a given detector resolution. The AM extracts roads compatible with a given event during detector read-out. Two important variables characterize the quality of the AM bank: its “coverage” and the level of “found fakes”. The coverage, which describes the geometric efficiency of a bank, is defined as the fraction of tracks that match at least a pattern in the bank. Given a certain road size, the coverage of the bank can be increased just adding patterns to the bank, while the number of found fakes unfortunately is roughly proportional to this number of patterns in the bank. M...

Annovi, A; The ATLAS collaboration; Beretta, M; Bossini, E; Crescioli, F; Dell'Orso, M; Giannetti, P; Hoff, J; Liberali, V; Liu, T; Magalotti, D; Piendibene, M; Sacco, A; Schoening, A; Soltveit, H K; Stabile, A; Tripiccione, R; Vitillo, R; Volpi, G

2011-01-01T23:59:59.000Z

486

Characterization of extrasolar terrestrial planets from diurnal photometric variability  

E-Print Network (OSTI)

The detection of massive planets orbiting nearby stars has become almost routine, but current techniques are as yet unable to detect terrestrial planets with masses comparable to the Earth's. Future space-based observatories to detect Earth-like planets are being planned. Terrestrial planets orbiting in the habitable zones of stars-where planetary surface conditions are compatible with the presence of liquid water-are of enormous interest because they might have global environments similar to Earth's and even harbor life. The light scattered by such a planet will vary in intensity and colour as the planet rotates; the resulting light curve will contain information about the planet's properties. Here we report a model that predicts features that should be discernible in light curves obtained by low-precision photometry. For extrasolar planets similar to Earth we expect daily flux variations up to hundreds of percent, depending sensitively on ice and cloud cover. Qualitative changes in surface or climate generate significant changes in the predicted light curves. This work suggests that the meteorological variability and the rotation period of an Earth-like planet could be derived from photometric observations. Other properties such as the composition of the surface (e.g., ocean versus land fraction), climate indicators (for example ice and cloud cover), and perhaps even signatures of Earth-like plant life could be constrained or possibly, with further study, even uniquely determined.

E. B. Ford; S. Seager; E. L. Turner

2001-09-04T23:59:59.000Z

487

Feasibility of wavelet expansion methods to treat the energy variable  

Science Conference Proceedings (OSTI)

This paper discusses the use of the Discrete Wavelet Transform (DWT) to implement a functional expansion of the energy variable in neutron transport. The motivation of the work is to investigate the possibility of adapting the expansion level of the neutron flux in a material region to the complexity of the cross section in that region. If such an adaptive treatment is possible, 'simple' material regions (e.g., moderator regions) require little effort, while a detailed treatment is used for 'complex' regions (e.g., fuel regions). Our investigations show that in fact adaptivity cannot be achieved. The most fundamental reason is that in a multi-region system, the energy dependence of the cross section in a material region does not imply that the neutron flux in that region has a similar energy dependence. If it is chosen to sacrifice adaptivity, then the DWT method can be very accurate, but the complexity of such a method is higher than that of an equivalent hyper-fine group calculation. The conclusion is thus that, unfortunately, the DWT approach is not very practical. (authors)

Van Rooijen, W. F. G. [Research Inst. of Nuclear Engineering, Univ. of Fukui, Kanawa-cho 1-2-4, 914-0055, Fukui-ken, Tsuruga-shi (Japan)

2012-07-01T23:59:59.000Z

488

How to Avoid Overestimating Variable Speed Drive Savings  

E-Print Network (OSTI)

This paper addresses eight factors that can cause incorrect and often excessive savings estimates for pump and fan variable speed drive applications. To avoid overestimating savings: 1. Identify system elements that affect head pressure independently of flow rate. 2. Identify system elements that change head pressure in proportion to less than the square of flow rate. 3. Account for dynamic system elements, especially when in systems with minimum static pressure controls. 4. Consider changes in fan efficiency. 5. Account for decreases in motor efficiency at part load, particularly for smaller motors below about 35 percent load. 6. Recognize that existing part load controls may be more efficient than expected. 7. Account for drive losses. 8. Measure full flow power, rather than assuming it is the same as motor nameplate or design power. For many pump and fan systems, none of the eight factors will apply, or their effects will be negligible. However, analysts should consider their applicability when estimating savings for a particular system. This paper provides tools for accounting for the factors.

Maxwell, J. B.

2005-01-01T23:59:59.000Z

489

VARIABLE CHARGE MOTION FOR 2007-2010 DIESEL ENGINES  

DOE Green Energy (OSTI)

The use of direct injection diesel engines in US heavy duty pickup truck applications is becoming increasingly popular with over 250,000 produced in 2002. The high torque density and greatly improved fuel consumption offer distinct advantages to the end user. 2007 and 2010 emissions legislation will present another set of technical and product cost challenges to this type of powertrain. The introduction of efficient aftertreatment systems is mandatory to the success of these engines but optimization of engine-out emissions is also a critical element. Much has been written on the improvements in modern fuel systems which offer great flexibility for the direct introduction of fuel into the cylinder. This paper presents complementary technologies which allow improved air/fuel mixing processes by the additional flexibility of variable in-cylinder charge motion. This approach is particularly applicable to pick-up truck engines, which require high BMEP levels across a wide engine speed range to offer the driveability demanded by the consumer. Design solutions for 2 valve and 4 valve engines are presented along with the potential emissions and fuel consumption benefits.

Maier, J

2003-08-24T23:59:59.000Z

490

Studying the Pulsation of Mira Variables in the Ultraviolet  

E-Print Network (OSTI)

We present results from an empirical study of the Mg II h & k emission lines of selected Mira variable stars, using spectra from the International Ultraviolet Explorer (IUE). The stars all exhibit similar Mg II behavior during the course of their pulsation cycles. The Mg II flux always peaks after optical maximum near pulsation phase 0.2-0.5, although the Mg II flux can vary greatly from one cycle to the next. The lines are highly blueshifted, with the magnitude of the blueshift decreasing with phase. The widths of the Mg II lines are also phase-dependent, decreasing from about 70 km/s to 40 km/s between phase 0.2 and 0.6. We also study other UV emission lines apparent in the IUE spectra, most of them Fe II lines. These lines are much narrower and not nearly as blueshifted as the Mg II lines. They exhibit the same phase-dependent flux behavior as Mg II, but they do not show similar velocity or width variations.

Brian E. Wood; Margarita Karovska

2000-02-14T23:59:59.000Z

491

The Absolute Magnitude of RRc Variables From Statistical Parallax  

E-Print Network (OSTI)

We present the first definitive measurement of the absolute magnitude of RR Lyrae c-type variable stars (RRc) determined purely from statistical parallax. We use a sample of 247 RRc selected from the All Sky Automated Survey (ASAS) for which high-quality light curves, photometry and proper motions are available. We obtain high-resolution echelle spectra for these objects to determine radial velocities and abundances as part of the Carnegie RR Lyrae Survey (CARRS). We find that M_(V,RRc) = 0.52 +/- 0.11 at a mean metallicity of [Fe/H] = -1.59. This is to be compared with previous estimates for RRab stars (M_(V,RRab) = 0.75 +/- 0.13 and the only direct measurement of an RRc absolute magnitude (RZ Cephei, M_(V, RRc) = 0.27 +/- 0.17). We find the bulk velocity of the halo to be (W_pi, W_theta, W_z) = (10.9,34.9,7.2) km/s in the radial, rotational and vertical directions with dispersions (sigma_(W_pi), sigma_(W_theta), sigma_(W_z)) = (154.7, 103.6, 93.8) km/s. For the disk, we find (W_pi, W_theta, W_z) = (8.5, 213...

Kollmeier, Juna A; Burns, Christopher R; Gould, Andrew; Thompson, Ian B; Preston, George W; Sneden, Christopher; Crane, Jeffrey D; Dong, Subo; Madore, Barry F; Morrell, Nidia; Prieto, Jose L; Shectman, Stephen; Simon, Joshua D; Villanueva, Edward

2012-01-01T23:59:59.000Z

492

Can hidden correlations mimic a variable fine structure constant?  

E-Print Network (OSTI)

Murphy et al. (2003a, MNRAS, 345, 609) claim to find evidence of cosmological variations of the fine structure constant $\\alpha$ in the spectra of intervening QSO absorption line systems. We find that this result is affected by systematic effects. The $\\alpha$ values estimated in individual line systems depend on the set of atomic transitions used and therefore the quoted dependence on the cosmic age may reflect the fact that different sets of transitions are used at different redshifts. A correlation between line shifts and relative optical depths of the atomic transitions is also present. This correlation is very tight for a high-redshift subsample and accounts for the anomalous dispersion of the $\\alpha$ values found by Murphy et al. (2003a) in this subsample. The above correlations are consistent with a scenario in which gravitational redshift, caused by the gravity of the dark halo, contributes to the shift in frequency of individual components. Gravitational redshift causes differential spectral shifts of the same order as magnitude of those measured. In the presence of line misidentification, these shifts can be interpreted in terms of a variable $\\alpha$. In order to verify the gravitational redshift hypothesis, a direct access to Murphy et al. (2003a) data, or to a large amount of new high resolution data, is necessary.

Rino Bandiera; Edvige Corbelli

2005-04-15T23:59:59.000Z

493

VARIABILITY OF THE INFRARED EXCESS OF EXTREME DEBRIS DISKS  

SciTech Connect

Debris disks with extremely large infrared excesses (fractional luminosities >10{sup -2}) are rare. Those with ages between 30 and 130 Myr are of interest because their evolution has progressed well beyond that of protoplanetary disks (which dissipate with a timescale of order 3 Myr), yet they represent a period when dynamical models suggest that terrestrial planet building may still be progressing through large, violent collisions that could yield large amounts of debris and large infrared excesses. For example, our Moon was formed through a violent collision of two large protoplanets during this age range. We report two disks around the solar-like stars ID8 and HD 23514 in this age range where the 24 {mu}m infrared excesses vary on timescales of a few years, even though the stars are not variable in the optical. Variations this rapid are difficult to understand if the debris is produced by collisional cascades, as it is for most debris disks. It is possible that the debris in these two systems arises in part from condensates from silicate-rich vapor produced in a series of violent collisions among relatively large bodies. If their evolution is rapid, the rate of detection of extreme excesses would indicate that major collisions may be relatively common in this age range.

Meng, Huan Y. A.; Rieke, George H. [Department of Planetary Sciences, Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 (United States); Su, Kate Y. L.; Rujopakarn, Wiphu [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Ivanov, Valentin D. [European Southern Observatory, Ave. Alonso de Cordova 3107, Casilla 19, Santiago, 19001 (Chile); Vanzi, Leonardo [Department of Electrical Engineering and Center of Astro Engineering, Pontificia Universidad Catolica de Chile, Ave. Vicuna Mackenna 4860, Santiago (Chile)

2012-05-20T23:59:59.000Z

494

Stochastic versus deterministic variability in simple neuronal circuits  

E-Print Network (OSTI)

ABSTRACT Long timesenes of monosynati la-afferent to alpha-motoneuron reflexeswere recorded inte L7 or Si ventral roots in te cat Time serieswerecolleted beforeand afterspinalization atT13 duringconstantampitude stimulatons ofgroup la muscle afferents in the riceps surae muscle nerves. Using autocorrelation to analyze te linearcorrelaton inFte time series demonstrated oscillations inthedecerebratestate (4/4) Ftatwere eliminated afterspinalizain (5/5).Threetestsfordeterninism were applied tothese series: 1) local flow, 2) loal dispersion, and 3) nonlinear prediction. These algorithmswere validated with time senes generated from known determinisc equaions. For each expenrmental and teoretical time senes used, matched time-series ofstochastic surrogate dataweregenerated toserveas mathematicaland statstcal ctrols.Two ofthetime series colected in thedecerebrate state (2/4) demonstrated evidence fordeterministicsbucture. This structurecould notbeaccounted forbytheautocorrelation inthedata,andwasabolishedfollowingspinalizaon. Noneofthetimeseriescollected inthespinalized state (0/5) demonstrated evkience of determinism. Although monosynaptic reflex variability is generally stochastic in the spinalized state, this simple driven system may display deterministic behavior in the decerebrate state.

Taeun Chang; Steven J. Schiff; Tim Sauer; Jean-pierre Gossard; Robert E. Burke

1994-01-01T23:59:59.000Z

495

Variable current speed controller for eddy current motors  

DOE Patents (OSTI)

A speed control system for eddy current motors is provided in which the current to the motor from a constant frequency power source is varied by comparing the actual motor speed signal with a setpoint speed signal to control the motor speed according to the selected setpoint speed. A three-phase variable voltage autotransformer is provided for controlling the voltage from a three-phase power supply. A corresponding plurality of current control resistors is provided in series with each phase of the autotransformer output connected to inputs of a three-phase motor. Each resistor is connected in parallel with a set of normally closed contacts of plurality of relays which are operated by control logic. A logic circuit compares the selected speed with the actual motor speed obtained from a digital tachometer monitoring the motor spindle speed and operated the relays to add or substract resistance equally in each phase of the motor input to vary the motor current to control the motor at the selected speed.

Gerth, H.L.; Bailey, J.M.; Casstevens, J.M.; Dixon, J.H.; Griffith, B.O.; Igou, R.E.

1982-03-12T23:59:59.000Z

496

A structure-based database of antibody variable domain diversity  

Science Conference Proceedings (OSTI)

The diversity of natural antibodies is limited by the genetic mechanisms that engender diversity and the functional requirements of antigen binding. Using an in vitro-evolved autonomous heavy chain variable domain (V{sub H}H-RIG), we have investigated the limits of structurally-tolerated diversity in the three complementarity-determining regions and a fourth loop within the third framework region. We determined the X-ray crystal structure of the V{sub H}H-RIG domain at 1.9 {angstrom} resolution and used it to guide the design of phage-displayed libraries encompassing the four loops. The libraries were subjected to selections for structural stability, and a database of structurally-tolerated sequences was compiled from the sequences of approximately 1000 unique clones. The results reveal that all four loops accommodate significantly greater diversity than is observed in nature. Thus, it appears that most sequence biases in the natural immune repertoire arise from factors other than structural constraints and, consequently, it should be possible to enhance the functions of antibodies significantly through in vitro evolution.

Bond, C.J.; Wiesmann, C.; Marsters, Jr., J.C.; Sidhu, S.S. (Genentech)

2010-07-13T23:59:59.000Z

497

Planning for Variable Generation Integration through Balancing Authorities Consolidation  

Science Conference Proceedings (OSTI)

As more and more variable generation is integrated into power grids, many challenges and concerns arise for an individual balancing authority (BA) to balance the system with limited resources. Consolidating balancing authorities provides a promising method to mitigate these problems by enabling the sharing of resources through operating different BAs as a single BA. The diversity in load and renewable generation over a wide area can be effectively leveraged, which makes it possible to achieve significant savings in balancing requirements. This paper develops a detailed procedure to compute savings in load following and regulation service requirements due to BAs consolidation. It proposes several evaluation metrics for demonstrating the benefits of BA consolidation. Several study scenarios are designed for a set of BAs in the western United States to test the proposed procedure. Results have shown significant savings in the capacity, ramp rate, and energy of balancing service requirements. Important factors affecting the savings, such as forecast accuracy and cross correlation between forecast errors, are also discussed.

Diao, Ruisheng; Samaan, Nader A.; Makarov, Yuri V.; Hafen, Ryan P.; Ma, Jian

2012-11-10T23:59:59.000Z

498

Dynamical paths and universality in continuous variables open systems  

E-Print Network (OSTI)

We address the dynamics of quantum correlations in continuous variable open systems and analyze the evolution of bipartite Gaussian states in independent noisy channels. In particular, upon introducing the notion of dynamical path through a suitable parametrization for symmetric states, we focus attention on phenomena that are common to Markovian and non-Markovian Gaussian maps under the assumptions of weak coupling and secular approximation. We found that the dynamical paths in the parameter space are universal, that is they do depend only on the initial state and on the effective temperature of the environment, with non Markovianity that manifests itself in the velocity of running over a given path. This phenomenon allows one to map non-Markovian processes onto Markovian ones and it may reduce the number of parameters needed to study a dynamical process, e.g. it may be exploited to build constants of motions valid for both Markovian and non-Markovian maps. Universality is also observed in the value of Gaussian discord at the separability threshold, which itself is a function of the sole initial conditions in the limit of high temperature. We also prove the existence of excluded regions in the parameter space, i.e. of sets of states which cannot be linked by any Gaussian dynamical map.

Andrea Cazzaniga; Sabrina Maniscalco; Stefano Olivares; Matteo G. A. Paris

2012-11-27T23:59:59.000Z

499

Entanglement, Purity, and Information Entropies in Continuous Variable Systems  

E-Print Network (OSTI)

Quantum entanglement of pure states of a bipartite system is defined as the amount of local or marginal ({\\em i.e.}referring to the subsystems) entropy. For mixed states this identification vanishes, since the global loss of information about the state makes it impossible to distinguish between quantum and classical correlations. Here we show how the joint knowledge of the global and marginal degrees of information of a quantum state, quantified by the purities or in general by information entropies, provides an accurate characterization of its entanglement. In particular, for Gaussian states of continuous variable systems, we classify the entanglement of two--mode states according to their degree of total and partial mixedness, comparing the different roles played by the purity and the generalized $p-$entropies in quantifying the mixedness and bounding the entanglement. We prove the existence of strict upper and lower bounds on the entanglement and the existence of extremally (maximally and minimally) entangled states at fixed global and marginal degrees of information. This results allow for a powerful, operative method to measure mixed-state entanglement without the full tomographic reconstruction of the state. Finally, we briefly discuss the ongoing extension of our analysis to the quantification of multipartite entanglement in highly symmetric Gaussian states of arbitrary $1 \\times N$-mode partitions.

Gerardo Adesso; Alessio Serafini; Fabrizio Illuminati

2005-06-06T23:59:59.000Z

500

Entanglement in continuous variable systems: Recent advances and current perspectives  

E-Print Network (OSTI)

We review the theory of continuous-variable entanglement with special emphasis on foundational aspects, conceptual structures, and mathematical methods. Much attention is devoted to the discussion of separability criteria and entanglement properties of Gaussian states, for their great practical relevance in applications to quantum optics and quantum information, as well as for the very clean framework that they allow for the study of the structure of nonlocal correlations. We give a self-contained introduction to phase-space and symplectic methods in the study of Gaussian states of infinite-dimensional bosonic systems. We review the most important results on the separability and distillability of Gaussian states and discuss the main properties of bipartite entanglement. These include the extremal entanglement, minimal and maximal, of two-mode mixed Gaussian states, the ordering of two-mode Gaussian states according to different measures of entanglement, the unitary (reversible) localization, and the scaling of bipartite entanglement in multimode Gaussian states. We then discuss recent advances in the understanding of entanglement sharing in multimode Gaussian states, including the proof of the monogamy inequality of distributed entanglement for all Gaussian states, and its consequences for the characterization of multipartite entanglement. We finally review recent advances and discuss possible perspectives on the qualification and quantification of entanglement in non Gaussian states, a field of research that is to a large extent yet to be explored.

Gerardo Adesso; Fabrizio Illuminati

2007-01-29T23:59:59.000Z