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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

Energy-dependence of skin-mode fraction in $E1$ excitations of neutron-rich nuclei  

E-Print Network [OSTI]

We have extensively investigated characters of the low-energy $E1$ strengths in $N>Z$ nuclei, by analyzing the transition densities obtained by the HF+RPA calculations with several effective interactions. Crossover behavior has been confirmed, from the skin mode at low energy to the $pn$ mode at higher energy. Decomposing the $E1$ strengths into the skin-mode, $pn$-mode and interference fractions, we show that the ratio of the skin-mode strength to the full strength may be regarded as a generic function of the excitation energy, insensitive to nuclides and effective interactions, particularly beyond Ni.

Nakada, H; Sawai, H

2015-01-01T23:59:59.000Z

2

Modes of Operation Encryption with Block Ciphers: Modes of Operation  

E-Print Network [OSTI]

(ECB) · Cipher Block Chaining mode (CBC) · Output Feedback mode (OFB) · Cipher Feedback mode (CFB) · Cipher Feedback mode (CFB) · Counter mode (CTR) · Galois Counter Mode (GCM) · All of the 6 modes have one

3

Observation of neutral modes in the fractional quantum Hall regime , H. Inoue1  

E-Print Network [OSTI]

-dimensional-electron gas under strong magnetic field, currents flow along the edges of the sample. For some particle, Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel 2 Department (FQHE) [1] regime along the edges of a two-dimensional- electron gas (2DEG) via edge modes

Kane, Charles

4

Behaviour and stability of Trivelpiece-Gould modes in non-neutral plasma containing small density fraction of background gas ions  

SciTech Connect (OSTI)

It is shown that the frequencies of Trivelpiece-Gould (TG) modes in non-neutral plasma can get into the low-frequency range due to the Doppler shift caused by plasma rotation in crossed fields. TG modes interact with the ion modes that leads to plasma instability. In paper the frequency spectrum of 'cold' electron plasma completely filling a waveguide and containing small density fraction of ions of background gas is determined numerically. For ions the kinetic description is used. Oscillations having azimuthal number m= 2 are considered. In this case both low- and upper-hybrid TG modes get into the low-frequency range. The spectrum consists of families of 'modified' ion cyclotron (MIC) modes and electron TG modes with the frequencies equal to hybrid frequencies with the Doppler shift. The growth rates of upper-hybrid modes are much faster than the growth rates of low-hybrid and MIC modes.

Yeliseyev, Y. N. [Institute of Plasma Physics, National Science Center Kharkov Institute of Physics and Technology, Akademicheskaya St., 1, 61108 Kharkov (Ukraine)

2013-03-19T23:59:59.000Z

5

Kink modes in pedestal  

SciTech Connect (OSTI)

Kink modes are investigated in pedestal for shaped tokamaks. An analytic combining criterion is presented. It lies on the middle of the sufficient criterion of Lortz and necessary criterion of Mercier giving a more restricted necessary criterion. Growth rates and mode structure are calculated. For large poloidal mode number, the modes are highly localized in both poloidal and radial directions. The modes increase rapidly when they approach to the resonant surface. They are typical of edge localized modes (ELMs). It is assumed that the modes vanish inside the next resonant surface, then, there seems to be a second stable region. Several mitigation methods for controlling ELMs are proposed.

Wang, Z. T. [Southwestern Institute of Physics, Chengdu 610041 (China) [Southwestern Institute of Physics, Chengdu 610041 (China); College of Physics Science and Technology, Sichuan University, Chengdu 610065 (China); He, Z. X.; Dong, J. Q.; Wang, Z. H.; Xu, M. [Southwestern Institute of Physics, Chengdu 610041 (China)] [Southwestern Institute of Physics, Chengdu 610041 (China); Xu, X. L.; Mou, M. L.; Sun, T. T.; Huang, J.; Chen, S. Y.; Tang, C. J. [College of Physics Science and Technology, Sichuan University, Chengdu 610065 (China)] [College of Physics Science and Technology, Sichuan University, Chengdu 610065 (China)

2014-03-15T23:59:59.000Z

6

Architecture AddressingModes  

E-Print Network [OSTI]

MIPS R2000 Architecture and Assembly (Part 1) 1. CPU Registers 2. Byte Order 3. AddressingModes 4­endian byte order 3 2 1 0 0 1 2 3 Or Byte number #12; AddressingModes . MIPS is a load/store architecture . RICS -- Load/Store architecture -- All instructions have equal length of 4 bytes -- Every register can

Nguyen, Dat H.

7

mode | OpenEI  

Open Energy Info (EERE)

mode mode Dataset Summary Description Supplemental Table 46 of EIA AEO 2011 Early Release Source EIA Date Released December 08th, 2010 (4 years ago) Date Updated Unknown Keywords AEO Annual Energy Outlook EIA Energy Information Administration Fuel mode TEF transportation Transportation Energy Futures Data text/csv icon Transportation_Sector_Energy_Use_by_Fuel_Type_Within_a_Mode.csv (csv, 144.3 KiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Annually Time Period 2008-2035 License License Open Data Commons Public Domain Dedication and Licence (PDDL) Comment Rate this dataset Usefulness of the metadata Average vote Your vote Usefulness of the dataset Average vote Your vote Ease of access Average vote Your vote Overall rating Average vote Your vote

8

Deriving a mode logic using failure modes and effects analysis  

Science Journals Connector (OSTI)

Modes are widely used to structure the behaviour of control systems. However, derivation and verification of a mode logic for complex systems is challenging due to a large number of modes and intricate mode transitions. In this paper, we propose an approach to deriving, formalising and verifying consistency of a mode logic for fault-tolerant control systems. We propose to use failure modes and effects analysis (FMEA) to systematically derive the fault tolerance part of the mode logic. We formalise the mode logic and define mode consistency properties for layered systems with reconfigurable components. We use our formalisation to develop and verify a mode-rich system by refinement in Event-B.

Yuliya Prokhorova; Linas Laibinis; Elena Troubitsyna; Kimmo Varpaaniemi; Timo Latvala

2012-01-01T23:59:59.000Z

9

Storage Ring Operation Modes  

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

Longitudinal bunch profile and Up: APS Storage Ring Parameters Longitudinal bunch profile and Up: APS Storage Ring Parameters Previous: Source Parameter Table Storage Ring Operation Modes Standard Operating Mode, top-up Fill pattern: 102 mA in 24 singlets (single bunches) with a nominal current of 4.25 mA and a spacing of 153 nanoseconds between singlets. Lattice configuration: Low emittance lattice with effective emittance of 3.1 nm-rad and coupling of 1%. Bunch length (rms): 33.5 ps. Refill schedule: Continuous top-up with single injection pulses occurring at a minimum of two minute intervals, or a multiple of two minute intervals. Special Operating Mode - 324 bunches, non top-up Fill pattern: 102 mA in 324 uniformly spaced singlets with a nominal single bunch current of 0.31 mA and a spacing of 11.37 nanoseconds between singlets.

10

Dual-Mode Hybrid/Two-Mode Hybrid Accomplishment  

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

Dual-Mode Hybrid/Two-Mode Hybrid Accomplishment Dual-Mode Hybrid/Two-Mode Hybrid Accomplishment DOE-funded research, in collaboration with Allison Buses and General Motors Corporation has led to the commercialization of a dramatically different hybrid transmission system for heavy-duty and light-duty applications. The Dual-Mode or Two-Mode hybrid system is an infinitely variable speed hybrid transmission that works with the engine and battery system and automatically chooses to operate in a parallel or series hybrid path to maximize efficiency and minimize emissions, fuel consumption and noise. Parallel and Series hybrid configurations are found on most hybrid vehicles today, both with their own pluses and minuses. The Dual- Mode/Two-Mode systems uses the positive characteristics from both systems to maximize fuel

11

Elemental Modes of Occurrence in an Illinois #6 Coal and Fractions Prepared by Physical Separation Techniques at a Coal Preparation Plant  

SciTech Connect (OSTI)

In order to gain better insight into elemental partitioning between clean coal and tailings, modes of occurrence have been determined for a number of major and trace elements (S, K, Ca, V, Cr, Mn, Fe, Zn, As, Se, Pb) in an Illinois No.6 coal and fractions prepared by physical separation methods at a commercial coal preparation plant. Elemental modes of occurrence were largely determined directly by XAFS or Moessbauer spectroscopic methods because the concentrations of major minerals and wt.% ash were found to be highly correlated for this coal and derived fractions, rendering correlations between individual elements and minerals ambiguous for inferring elemental modes of occurrence. Of the major elements investigated, iron and potassium are shown to be entirely inorganic in occurrence. Most (90%) of the iron is present as pyrite, with minor fractions in the form of clays and sulfates. All potassium is present in illitic clays. Calcium in the original coal is 80-90% inorganic and is divided between calcite, gypsum, and illite, with the remainder of the calcium present as carboxyl-bound calcium. In the clean coal fraction, organically associated Ca exceeds 50% of the total calcium. This organically-associated form of Ca explains the poorer separation of Ca relative to both K and ash. Among the trace elements, V and Cr are predominantly inorganically associated with illite, but minor amounts (5-15% Cr, 20-30% V) of these elements are also organically associated. Estimates of the V and Cr contents of illite are 420 ppm and 630 ppm, respectively, whereas these elements average 20 and 8 ppm in the macerals. Arsenic in the coal is almost entirely associated with pyrite, with an average As content of about 150 ppm, but some As ({approx} 10%) is present as arsenate due to minor oxidation of the pyrite. The mode of occurrence of Zn, although entirely inorganic, is more complex than normally noted for Illinois basin coals; about 2/3 is present in sphalerite, with lesser amounts associated with illite and a third form yet to be conclusively identified. The non-sulfide zinc forms are removed predominantly by the first stage of separation (rotary breaker), whereas the sphalerite is removed by the second stage (heavy media). Germanium is the only trace element determined to have a predominantly organic association.

Huggins, F.; Seidu, L; Shah, N; Huffman, G; Honaker, R; Kyger, J; Higgins, B; Robertson, J; Pal, S; Seehra, M

2009-01-01T23:59:59.000Z

12

Slow modes in Keplerian disks  

E-Print Network [OSTI]

Low-mass disks orbiting a massive body can support "slow" normal modes, in which the eigenfrequency is much less than the orbital frequency. Slow modes are lopsided, i.e., the azimuthal wavenumber m=1. We investigate the properties of slow modes, using softened self-gravity as a simple model for collective effects in the disk. We employ both the WKB approximation and numerical solutions of the linear eigenvalue equation. We find that all slow modes are stable. Discrete slow modes can be divided into two types, which we label g-modes and p-modes. The g-modes involve long leading and long trailing waves, have properties determined by the self-gravity of the disk, and are only present in narrow rings or in disks where the precession rate is dominated by an external potential. In contrast, the properties of p-modes are determined by the interplay of self-gravity and other collective effects. P-modes involve both long and short waves, and in the WKB approximation appear in degenerate leading/trailing pairs. Disks support a finite number---sometimes zero---of discrete slow modes, and a continuum of singular modes.

Scott Tremaine

2000-11-30T23:59:59.000Z

13

High Non-inductive Fraction H-mode Discharges Generated by High-harmonic Fast Wave Heating and Current Drive in the National Spherical Torus Experiment  

SciTech Connect (OSTI)

A deuterium H-mode discharge with a plasma current of 300 kA, an axial toroidal magnetic field of 0.55 T, and a calculated non-inductive plasma current fraction of 0.7 1 has been generated in the National Spherical Torus Experiment by 1.4MW of 30MHz high-harmonic fast wave (HHFW) heating and current drive. Seventy-five percent of the non-inductive current was generated inside an internal transport barrier that formed at a normalized minor radius 0.4. Three quarters of the non-inductive current was bootstrap current, and the remaining non-inductive current was generated directly by HHFW power inside a normalized minor radius 0.2. VC 2012 American Institute of Physics.

Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Kessel, C. E. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); Mueller, D. [Princeton Plasma Physics Laboratory (PPPL); Phillips, C. K. [Princeton Plasma Physics Laboratory (PPPL); Valeo, E. J. [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL); Ryan, Philip Michael [ORNL; Bonoli, P. [Massachusetts Institute of Technology (MIT); Harvey, R. W. [CompX, Del Mar, CA

2012-01-01T23:59:59.000Z

14

Flexure modes in carbon nanotubes  

Science Journals Connector (OSTI)

Phonons are calculated for single wall carbon nanotubes. Eigenvalues and eigenvectors are presented for armchair and zig-zag tubes. The model contains just three adjustable spring constants: two for first and second nearest neighbor directed bonds, and a third for radial bond-bending interactions. There are four low frequency modes at long wavelength: a longitudinal acoustical, a torsional mode, and two flexure modes.

G. D. Mahan and Gun Sang Jeon

2004-08-09T23:59:59.000Z

15

Mode Order Converter Using Tapered Multi-mode Interference Couplers  

E-Print Network [OSTI]

, and modes of guided light is essential for flexibility in photonic integrated circuit (PIC) design.3120) Integrated optics devices; (130.2790) Guided waves 1. Introduction Accommodating various sizes, shapes indices. One can define Am0 as the transmission of the fundamental mode in the output guide when exciting

Texas at Austin, University of

16

Mode synthesizing atomic force microscopy and mode-synthesizing sensing  

DOE Patents [OSTI]

A method of analyzing a sample that includes applying a first set of energies at a first set of frequencies to a sample and applying, simultaneously with the applying the first set of energies, a second set of energies at a second set of frequencies, wherein the first set of energies and the second set of energies form a multi-mode coupling. The method further includes detecting an effect of the multi-mode coupling.

Passian, Ali; Thundat, Thomas George; Tetard, Laurene

2013-05-17T23:59:59.000Z

17

Localized defect modes in graphene  

Science Journals Connector (OSTI)

We study the properties of localized vibrational modes associated with structural defects in a sheet of graphene. For the examples of the Stone-Wales defects, one- and two-atom vacancies, many-atom linear vacancies, and adatoms in a honeycomb lattice, we demonstrate that the local defect modes are characterized by stable oscillations with the frequencies lying outside the linear frequency bands of an ideal graphene. In the frequency spectral density of thermal oscillations, such localized defect modes lead to the additional peaks from the right side of the frequency band of the ideal sheet of graphene, which indicate the presence of defects in the graphene flakes.

Alexander V. Savin and Yuri S. Kivshar

2013-09-11T23:59:59.000Z

18

Peeling mode relaxation ELM model  

SciTech Connect (OSTI)

This paper discusses an approach to modelling Edge Localised Modes (ELMs) in which toroidal peeling modes are envisaged to initiate a constrained relaxation of the tokamak outer region plasma. Relaxation produces both a flattened edge current profile (which tends to further destabilise a peeling mode), and a plasma-vacuum negative current sheet which has a counteracting stabilising influence; the balance that is struck between these two effects determines the radial extent (rE) of the ELM relaxed region. The model is sensitive to the precise position of the mode rational surfaces to the plasma surface and hence there is a 'deterministic scatter' in the results that has an accord with experimental data. The toroidal peeling stability criterion involves the edge pressure, and using this in conjunction with predictions of rE allows us to evaluate the ELM energy losses and compare with experiment. Predictions of trends with the edge safety factor and collisionality are also made.

Gimblett, C. G. [EURATOM/UKAEA Fusion Association, Culham Science Centre Abingdon, Oxon, OX14 3DB (United Kingdom)

2006-11-30T23:59:59.000Z

19

Existence of Metastable Kinetic Modes  

SciTech Connect (OSTI)

The nonlinear evolution of resonantly driven systems, such as suprathermal particle driven modes in magnetically confined plasmas, is shown to strongly depend on the existence and nature of an underlying damping mechanism. When background resonant damping is present, subcritical states can take place. In particular, purely nonlinear steady-state regimes are found, whose destabilization threshold and saturation levels are calculated and validated using numerical simulations. This nonlinear behavior can be of relevance for acoustic modes in magnetically confined plasmas.

Nguyen, C.; Luetjens, H.; Garbet, X.; Grandgirard, V.; Lesur, M. [Centre de Physique Theorique, CNRS-Ecole Polytechnique, Palaiseau (France); CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); JAEA, Higashi-Ueno 6-9-3, Taitou, Tokyo, 110-0015 (Japan)

2010-11-12T23:59:59.000Z

20

Evaluation of Some Blockcipher Modes of Operation  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 4. CBC, CFB, and OFB Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 5. CTR; many are widely used. The modes under consideration are the encryption schemes ECB, CBC, CFB, OFB, CTR

Rogaway, Phillip

Note: This page contains sample records for the topic "modes mode fraction" 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

Evaluation of Some Blockcipher Modes of Operation  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 4. CBC, CFB, and OFB Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 5. CTR are widely used. The modes under consideration are the encryption schemes ECB, CBC, CFB, OFB, CTR, and XTS

Rogaway, Phillip

22

Occupant satisfaction in mixed-mode buildings.  

E-Print Network [OSTI]

Strategies for Mixed-Mode Buildings, Summary Report, CenterCBE). 2006. Website: Mixed-Mode Building Case Studies.Department of Environmental Building Research Establishment

Brager, Gail; Baker, Lindsay

2008-01-01T23:59:59.000Z

23

Occupant satisfaction in mixed-mode buildings  

E-Print Network [OSTI]

Environmental Quality in Green Buildings. Indoor Air; 14 (Strategies for Mixed-Mode Buildings, Summary Report, CenterCBE). 2006. Website: Mixed-Mode Building Case Studies.

Brager, Gail; Baker, Lindsay

2009-01-01T23:59:59.000Z

24

Tensor modes on the string theory landscape  

E-Print Network [OSTI]

We attempt an estimate for the distribution of the tensor mode fraction $r$ over the landscape of vacua in string theory. The dynamics of eternal inflation and quantum tunneling lead to a kind of democracy on the landscape, providing no bias towards large-field or small-field inflation regardless of the class of measure. The tensor mode fraction then follows the number frequency distributions of inflationary mechanisms of string theory over the landscape. We show that an estimate of the relative number frequencies for small-field vs large-field inflation, while unattainable on the whole landscape, may be within reach as a regional answer for warped Calabi-Yau flux compactifications of type IIB string theory.

Alexander Westphal

2012-12-22T23:59:59.000Z

25

Vibrational Modes of Adsorbed Atoms  

E-Print Network [OSTI]

for AronXe B. Neon Ar The lowest surface m ver g.ur ace mode branc mo d o' td 'th es of the " rin " ce e wit an adsorbate of modes assoc' tia ed with th e; there are for the ads stion, the bra h sorbate atoms I c 1.ons ranch labeled 2H s. n... , are the real ads teristic force con t tons ants for ad is evident that in Fi . 2 t "heavier" than th ig. the adsorbate is n e substrate M & terpretation b M, ) in tkis in- ecause the weaknes th l' ht ofth ds o ke adsorbate atoms (m, &m, IBRATIQNAI...

LAWRENCE, WR; Allen, Roland E.

1977-01-01T23:59:59.000Z

26

Coexistence of mixed mode multipactor  

SciTech Connect (OSTI)

Multipactor is a vacuum discharge based on secondary electron emission, and can manifest in many resonant and non-resonant modes. Where two or more types of multipactor coexist in the same device, it is found analytically that the one with the highest yield or the lowest order dominates.

Kishek, R. A. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)

2012-12-15T23:59:59.000Z

27

Properties of solar gravity mode signals in total irradiance observations  

SciTech Connect (OSTI)

Further evidence has been found that a significant fraction of the gravity mode power density in the total irradiance observations appears in sidebands of classified eigenfrequencies. These sidebands whose amplitudes vary from year to year are interpreted as harmonics of the rotational frequencies of the nonuniform solar surface. These findings are for non axisymmetric modes and corroborate the findings of Kroll, Hill and Chen for axisymmetric modes. It is demonstrated the the generation of the sidebands lifts the usual restriction on the parity of the eigenfunctions for modes detectable in total irradiance observations. 14 refs.

Kroll, R.J.; Chen, J.; Hill, H.A.

1988-01-01T23:59:59.000Z

28

Higher mode stability in spheromak equilibria  

Science Journals Connector (OSTI)

Spheromak equilibria with current profiles varying from peaked to hollow are analyzed for higher mode stability using a linear magnetohydrodynamic(MHD) code. For a cylindrical flux conserver with a radius equal to length the n=2 m=2 mode is found to be marginally unstable for the same hollow current profile as the n=1 m=1 mode. While the growth rate for this n=2 mode is much lower than the n=1 mode the presence of the n=2 mode may explain experimentally observed relaxation phenomena involving short wavelength turbulence in spheromak equilibria with sufficiently hollow current profiles.

U. Shumlak; T. R. Jarboe

1999-01-01T23:59:59.000Z

29

Block Cipher Modes Cetin Kaya Koc  

E-Print Network [OSTI]

Confidentiality Modes Five confidentiality modes: ECB, CBC, CFB, OFB, and CTR ECB: Electronic Codebook CBC: Cipher Block Chaining CFB: Cipher Feedback OFB: Output Feedback CTR: Counter Ko�c (http

30

Optical waveguides having flattened high order modes  

DOE Patents [OSTI]

A deterministic methodology is provided for designing optical fibers that support field-flattened, ring-like higher order modes. The effective and group indices of its modes can be tuned by adjusting the widths of the guide's field-flattened layers or the average index of certain groups of layers. The approach outlined here provides a path to designing fibers that simultaneously have large mode areas and large separations between the propagation constants of its modes.

Messerly, Michael Joseph; Beach, Raymond John; Heebner, John Edward; Dawson, Jay Walter; Pax, Paul Henry

2014-08-05T23:59:59.000Z

31

Vibration modes of giant gravitons  

Science Journals Connector (OSTI)

We examine the spectrum of small vibrations of giant gravitons when the gravitons expand in antide Sitter space and when they expand on the sphere. For any given angular harmonic, the modes are found to have frequencies related to the curvature length scale of the background; these frequencies are independent of radius (and hence angular momentum) of the brane itself. This implies that the holographic dual theory must have, in a given R charge sector, low-lying non-BPS excitations with level spacings independent of the R charge.

Sumit R. Das; Antal Jevicki; Samir D. Mathur

2000-12-21T23:59:59.000Z

32

Theory of Bernstein modes in graphene  

Science Journals Connector (OSTI)

We present a theoretical description of Bernstein modes that arise as a result of the coupling between plasmonlike collective excitations (upper-hybrid mode) and inter-Landau-level excitations, in graphene in a perpendicular magnetic field. These modes, which are apparent as avoided level crossings in the spectral function obtained in the random-phase approximation, are described to great accuracy in a phenomenological model. Bernstein modes, which may be measured in inelastic light-scattering experiments or in photoconductivity spectroscopy, are a manifestation of the Coulomb interaction between the electrons and may be used for a high-precision measurement of the upper-hybrid mode at small nonzero wave vectors.

R. Roldn; M. O. Goerbig; J.-N. Fuchs

2011-05-17T23:59:59.000Z

33

Predictions of Alpha Heating in ITER L-mode and H-mode Plasmas  

SciTech Connect (OSTI)

Predictions of alpha heating in L-mode and H-mode DT plasmas in ITER are generated using the PTRANSP code. The baseline toroidal field of 5.3 T, plasma current ramped to 15 MA and a flat electron density profile ramped to Greenwald fraction 0.85 are assumed. Various combinations of external heating by negative ion neutral beam injection, ion cyclotron resonance, and electron cyclotron resonance are assumed to start half-way up the density ramp. The time evolution of plasma temperatures and, for some cases, toroidal rotation are predicted assuming GLF23 and boundary parameters. Significant toroidal rotation and flow-shearing rates are predicted by GLF23 even in the L-mode phase with low boundary temperatures, and the alpha heating power is predicted to be significant if the power threshold for the transition to H-mode is higher than the planned total heating power. The alpha heating is predicted to be 8-76 MW in L-mode at full density. External heating mixes with higher beam injection power have higher alpha heating power. Alternatively if the toroidal rotation is predicted assuming that the ratio of the momentum to thermal ion energy conductivity is 0.5, the flow-shearing rate is predicted to have insignificant effects on the GLF23- predicted temperatures, and alpha heating is predicted to be 8-20 MW. In H-mode plasmas the alpha heating is predicted to depend sensitively on the assumed pedestal temperatures. Cases with fusion gain greater than 10 are predicted to have alpha heating greater than 80 MW.

R.V. Budny

2011-01-06T23:59:59.000Z

34

Representation of Ideal Magnetohydrodynamic Modes  

SciTech Connect (OSTI)

One of the most fundamental properties of ideal magnetohydrodynamics is the condition that plasma motion cannot change magnetic topology. The conventional representation of ideal magnetohydrodynamic modes by perturbing a toroidal equilibrium field through ? ? = ? X (xi X B) ensures that ? B ? ? = 0 at a resonance, with ? labelling an equilibrium flux surface. Also useful for the analysis of guiding center orbits in a perturbed field is the representation ? ? = ? X ?B. These two representations are equivalent, but the vanishing of ? B ?? at a resonance is necessary but not sufficient for the preservation of field line topology, and a indiscriminate use of either perturbation in fact destroys the original equilibrium flux topology. It is necessary to find the perturbed field to all orders in xi to conserve the original topology. The effect of using linearized perturbations on stability and growth rate calculations is discussed

Roscoe B. White

2013-01-15T23:59:59.000Z

35

Graphene sustained nonlinear modes in dielectric waveguides  

Science Journals Connector (OSTI)

We discuss the existence of nonlinear modes sustained by graphene layers in dielectric waveguides. Taking advantage of the almost two dimensional nature of graphene, we introduce the...

Auditore, Aldo; De Angelis, Costantino; Locatelli, Andrea; Boscolo, Stefano; Midrio, Michele; Romagnoli, Marco; Capobianco, Antonio-Daniele; Nalesso, Gianfranco

2013-01-01T23:59:59.000Z

36

FMEA (Failure Mode and Effects Analysis)  

Science Journals Connector (OSTI)

FMEA (Failure Mode and Effects Analysis; Fehlermglichkeits- und Einflussanalyse) als universelles Methodenmodell folgt dem Grundgedanken einer prventiven Fehlervermeidung anstelle einer nachsorgenden Fehler...

A. Gbel

2014-01-01T23:59:59.000Z

37

Mode I - mode II delamination fractrue toughness of a unidirectional graphite/epoxy composite  

E-Print Network [OSTI]

MODE I - MODE II DELAMINATION FRACTURE TOUGHNESS OF A UNIDIRECTIONAL GRAPHITE/EPOXY COMPOSITE A Thesis by PETER STEPHEN VANDERKLEY Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE Demember 1981 Najor Subject: Mechanical Engineering MODE I - MODE II DELAMINATION FRACTURE TOUGHNESS OF A UNIDIRECTIONAL GRAPHITE/EPOXY COMPOSITE A Thesis by PETER STEPHEN VANDERKLEY Approved as to style and content by...

Vanderkley, Peter Stephen

2012-06-07T23:59:59.000Z

38

New proofs for old modes Mark Wooding  

E-Print Network [OSTI]

the standard block cipher modes of operation: CBC, CFB, and OFB and analyse their security. We don't look in (full­width) CFB and OFB modes and that generalized counters encrypted using the block cipher (with Ciphertext feedback (CFB) en­ cryption 19 4.1 Description . . . . . . . . . 19 4.2 Sliding strings

39

New proofs for old modes Mark Wooding  

E-Print Network [OSTI]

the standard block cipher modes of operation: CBC, CFB, and OFB and analyse their security. We don't look in (full-width) CFB and OFB modes and that generalized counters encrypted using the block cipher (with Ciphertext feedback (CFB) en- cryption 19 4.1 Description . . . . . . . . . 19 4.2 Sliding strings

40

2009 Raj JainCSE571SWashington University in St. Louis Modes ofModes of  

E-Print Network [OSTI]

, CFB, CTR 2. Privacy+Integrity 3. DES Attacks 4. 3DES and its design Ref: Chapter 4 of textbook. #12. Electronic Code Book (ECB) 2. Cipher Block Chaining (CBC) 3. Cipher Feedback Mode (CFB) 4. Output Feedback University in St. Louis 4. k4. k--Bit Cipher Feedback Mode (CFB)Bit Cipher Feedback Mode (CFB) ! Key Stream

Jain, Raj

Note: This page contains sample records for the topic "modes mode fraction" 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

Guiding Center Equations for Ideal Magnetohydrodynamic Modes  

SciTech Connect (OSTI)

Guiding center simulations are routinely used for the discovery of mode-particle resonances in tokamaks, for both resistive and ideal instabilities and to find modifications of particle distributions caused by a given spectrum of modes, including large scale avalanches during events with a number of large amplitude modes. One of the most fundamental properties of ideal magnetohydrodynamics is the condition that plasma motion cannot change magnetic topology. The conventional representation of ideal magnetohydrodynamic modes by perturbing a toroidal equilibrium field through ?~B = ? X (? X B) however perturbs the magnetic topology, introducing extraneous magnetic islands in the field. A proper treatment of an ideal perturbation involves a full Lagrangian displacement of the field due to the perturbation and conserves magnetic topology as it should. In order to examine the effect of ideal magnetohydrodynamic modes on particle trajectories the guiding center equations should include a correct Lagrangian treatment. Guiding center equations for an ideal displacement ? are derived which perserve the magnetic topology and are used to examine mode particle resonances in toroidal confinement devices. These simulations are compared to others which are identical in all respects except that they use the linear representation for the field. Unlike the case for the magnetic field, the use of the linear field perturbation in the guiding center equations does not result in extraneous mode particle resonances.

Roscoe B. White

2013-02-21T23:59:59.000Z

42

Mixed Mode Fuel Injector And Injection System  

DOE Patents [OSTI]

A fuel injector includes a homogenous charge nozzle outlet set and a conventional nozzle outlet set that are controlled respectively by first and second three way needle control valves. Each fuel injector includes first and second concentric needle valve members. One of the needle valve members moves to an open position for a homogenous charge injection event, while the other needle valve member moves to an open position for a conventional injection event. The fuel injector has the ability to operate in a homogenous charge mode with a homogenous charge spray pattern, a conventional mode with a conventional spray pattern or a mixed mode.

Stewart, Chris Lee (Normal, IL); Tian, Ye (Bloomington, IL); Wang, Lifeng (Normal, IL); Shafer, Scott F. (Morton, IL)

2005-12-27T23:59:59.000Z

43

Differential rotation of nonlinear r-modes  

Science Journals Connector (OSTI)

The differential rotation of r-modes is investigated within the nonlinear theory up to second order in the mode amplitude in the case of a slowly rotating, Newtonian, barotropic, perfect-fluid star. We find a nonlinear extension of the linear r-mode, which represents differential rotation that produces large scale drifts of fluid elements along stellar latitudes. This solution includes a piece induced by first-order quantities and another one that is a pure second-order effect. Since the latter is stratified on cylinders, it cannot cancel differential rotation induced by first-order quantities, which is not stratified on cylinders. It is shown that, unlike the situation in the linearized theory, r-modes do not preserve the vorticity of fluid elements at second order. It is also shown that the physical angular momentum and energy of the perturbation are, in general, different from the corresponding canonical quantities.

Paulo M. S

2004-04-02T23:59:59.000Z

44

PLASTIC DEFORMATIONPLASTIC DEFORMATION Modes of Deformation  

E-Print Network [OSTI]

PLASTIC DEFORMATIONPLASTIC DEFORMATION Modes of Deformation The Uniaxial Tension Test Mechanisms underlying Plastic Deformation Strengthening mechanisms Mechanical Metallurgy George E Dieter McClick here to know about all the mechanisms by which materials fail #12;Slip (Dislocation motion) Plastic

Subramaniam, Anandh

45

Whispering-gallery-mode-based seismometer  

SciTech Connect (OSTI)

A whispering-gallery-mode-based seismometer provides for receiving laser light into an optical fiber, operatively coupling the laser light from the optical fiber into a whispering-gallery-mode-based optical resonator, operatively coupling a spring of a spring-mass assembly to a housing structure; and locating the whispering-gallery-mode-based optical resonator between the spring-mass assembly and the housing structure so as to provide for compressing the whispering-gallery-mode-based optical resonator between the spring-mass assembly and the housing structure responsive to a dynamic compression force from the spring-mass assembly responsive to a motion of the housing structure relative to an inertial frame of reference.

Fourguette, Dominique Claire; Otugen, M Volkan; Larocque, Liane Marie; Ritter, Greg Aan; Meeusen, Jason Jeffrey; Ioppolo, Tindaro

2014-06-03T23:59:59.000Z

46

Rotary Mode Core Sample System availability improvement  

SciTech Connect (OSTI)

The Rotary Mode Core Sample System (RMCSS) is used to obtain stratified samples of the waste deposits in single-shell and double-shell waste tanks at the Hanford Site. The samples are used to characterize the waste in support of ongoing and future waste remediation efforts. Four sampling trucks have been developed to obtain these samples. Truck I was the first in operation and is currently being used to obtain samples where the push mode is appropriate (i.e., no rotation of drill). Truck 2 is similar to truck 1, except for added safety features, and is in operation to obtain samples using either a push mode or rotary drill mode. Trucks 3 and 4 are now being fabricated to be essentially identical to truck 2.

Jenkins, W.W.; Bennett, K.L.; Potter, J.D. [Westinghouse Hanford Co., Richland, WA (United States); Cross, B.T.; Burkes, J.M.; Rogers, A.C. [Southwest Research Institute (United States)

1995-02-28T23:59:59.000Z

47

Two-Mode Theory of BEC Interferometry  

E-Print Network [OSTI]

A theory of BEC interferometry in an unsymmetrical double-well trap has been developed for small boson numbers, based on the two-mode approximation. The bosons are initially in the lowest mode of a single well trap, which is split into a double well and then recombined. Possible fragmentations into separate BEC states in each well during the splitting/recombination process are allowed for. The BEC is treated as a giant spin system, the fragmented states are eigenstates of S^2 and Sz. Self-consistent sets of equations for the amplitudes of the fragmented states and for the two single boson mode functions are obtained. The latter are coupled Gross-Pitaevskii equations. Interferometric effects may be measured via boson numbers in the first excited mode

B J Dalton

2007-02-03T23:59:59.000Z

48

Texas Feedgrain Flows and Transportation Modes, 1974.  

E-Print Network [OSTI]

ELEVATO RS AND FEEDMILLS . . . Destinations ............................ . .... . . . Modes of Transpo rtation of Grain Shipments ... .. . Destinations of Intraregi on and Interregion S Modes o f Transportation of Intraregion and Interregion Shipments.... Texas feedyards, receiving almost 31 per cent of the grain sorghum shipments of the elevators, ranked as the second most important market outlet. The remainder of the shipments was to out-of-state destinations (6.4 percent) and other Texas elevators...

Fuller, Stephen W.; Knudson, L. Bruce

1977-01-01T23:59:59.000Z

49

Singular Modes of the Electromagnetic Field  

E-Print Network [OSTI]

We show that the mode corresponding to the point of essential spectrum of the electromagnetic scattering operator is a vector-valued distribution representing the square root of the three-dimensional Dirac's delta function. An explicit expression for this singular mode in terms of the Weyl sequence is provided and analyzed. An essential resonance thus leads to a perfect localization (confinement) of the electromagnetic field, which in practice, however, may result in complete absorption.

Neil V. Budko; Alexander B. Samokhin

2006-06-15T23:59:59.000Z

50

Singular Modes of the Electromagnetic Field  

E-Print Network [OSTI]

We show that the mode corresponding to the point of essential spectrum of the electromagnetic scattering operator is a vector-valued distribution representing the square root of the three-dimensional Dirac's delta function. An explicit expression for this singular mode in terms of the Weyl sequence is provided and analyzed. An essential resonance thus leads to a perfect localization (confinement) of the electromagnetic field, which in practice, however, may result in complete absorption.

Budko, N V; Budko, Neil V.; Samokhin, Alexander B.

2006-01-01T23:59:59.000Z

51

Electroweak strings, zero modes and baryon number  

Science Journals Connector (OSTI)

The Dirac equations for leptons and quarks in the background of an electroweak Zstring have zero mode solutions. If two loops of electroweak string are linked, the zero modes on one of the loops interacts with the other loop via an Aharanov-Bohm interaction. The effects of this interaction are briefly discussed and it is shown that the fermions induce a baryon number on linked loops of Zstring.

Tanmay Vachaspati

1995-01-01T23:59:59.000Z

52

Modes of storage ring coherent instabilities  

SciTech Connect (OSTI)

Longitudinal impedance in a beam and various modes of longitudinal coherent instabilities are discussed. The coasting beam coherent instability, microwave instability, and single-bunch longitudinal coherent instabilities are considered. The Vlasov equation is formulated, and a method of solving it is developed. The synchrotron modes are treated, which take the possible bunch shape distortion fully into consideration. A method of treating the synchrotron mode coupling in the case of a small bunch is discussed which takes advantage of the fact that only a few of the synchrotron modes can contribute in such a case. The effect of many bunches on the coherent motion of the beam and the longitudinal symmetric coupled bunch modes are discussed. The transverse impedance is then introduced, and the transverse coasting beam instability is discussed. Various bunched beam instabilities are discussed, including both single bunch instabilities and coupled bunch instabilities. The Vlasov equation for transverse as well as longitudinal motion of particles is introduced as well as a method of solving it within a linear approximation. Head-tail modes and short bunch instabilities and strong coupling instabilities in the long bunch case are covered. (LEW)

Wang, J.M.

1986-12-01T23:59:59.000Z

53

The Slow Manifold of a Five-Mode Model  

Science Journals Connector (OSTI)

The slow manifold of an inviscid five-mode model introduced by Lorenz is investigated. When the influence of the gravity modes on the Rossby modes is neglected, the analytical solution given by Lorenz and Krishnamurthy is generalized. When ...

John P. Boyd

1994-04-01T23:59:59.000Z

54

Mode Initialization for On-line Estimation of Power System Electromechanical Modes  

SciTech Connect (OSTI)

Measurement-based mode estimation methods are utilized to estimate electromechanical modes of a power system using phasor measurement units (PMU) data. These methods need to extract a certain amount of information before they can give useable mode estimation. Traditionally, the information is gathered solely from measurement data. Priori mode information from other resources (e.g. model eigenvalue analysis, engineering knowledge) are not fully utilized. For real time application, this means that mode estimation takes time to converge. By adding a mode regularization term in the objective function, this paper proposes a mode initialization method to include priori mode information in a regularized robust recursive least squares (R3LS) algorithm for on-line mode estimation. The proposed method is tested using a simple model, a 17 machine model and is shown to be able to shorten the convergence period of the R3LS algorithm. The proposed method is also applied on the measurement data recorded right before a major power outage in the western North American Grid on August 10th 1996 to show its potential applica-tion in detecting an approaching small signal stability problem.

Zhou, Ning; Trudnowski, Daniel; Pierre, John W.

2009-03-18T23:59:59.000Z

55

Stabilization of ballooning modes with sheared toroidal rotation  

SciTech Connect (OSTI)

A new code demonstrates the stabilization of MHD ballooning modes by sheared toroidal rotation. A shifted-circle model is used to elucidate the physics and numerically reconstructed equilibria are used to analyze DIII-D discharges. In the ballooning representation, the modes shift periodically along the field line to the next point of unfavorable curvature. The shift frequency (d{Omega}/dq where {Omega} is the angular toroidal velocity and q is the safety factor) is proportional to the rotation shear and inversely proportional to the magnetic shear. Stability improves with increasing shift frequency and, in the shifted circle model, direct stable access to the second stability regime occurs when this frequency is a fraction of the Alfven frequency {omega}{sub A} = V{sub A}/qR. Shear stabilization is also demonstrated for an equilibrium reconstruction of a DIII-D VH-mode.

Miller, R.L.; Waelbroeck, F.W.; Lao, L.L.; Taylor, T.S.

1994-11-01T23:59:59.000Z

56

Mixed-mode diesel HCCI with External Mixture Formation: Preliminary...  

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

Mixed-mode diesel HCCI with External Mixture Formation: Preliminary Results Mixed-mode diesel HCCI with External Mixture Formation: Preliminary Results 2003 DEER Conference...

57

Modeling Combustion Control for High Power Diesel Mode Switching  

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

and Emissions Research Conference 2010 Modeling Combustion Control for High Power Diesel Mode Switching P-20 Motivation * High power LTC-diesel mode operation * Transient...

58

Modeling Combustion Control for High Power Diesel Mode Switching...  

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

Combustion Control for High Power Diesel Mode Switching Modeling Combustion Control for High Power Diesel Mode Switching Poster presentation given at the 16th Directions in...

59

Unregulated Emissions from High-Efficiency Clean Combustion Modes...  

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

Unregulated Emissions from High-Efficiency Clean Combustion Modes - ORNL-FEERC Unregulated Emissions from High-Efficiency Clean Combustion Modes - ORNL-FEERC Poster presentation at...

60

Fact #636: August 16, 2010 Transportation Energy Use by Mode...  

Energy Savers [EERE]

by Mode, 2008 Bar graph showing the transportation energy use by mode (buses, rail, pipeline, water, air, mediumheavy trucks, and light vehicles) for 2008. For more detailed...

Note: This page contains sample records for the topic "modes mode fraction" 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

Analysis of electromagnetic modes excited in overmoded structure terahertz source  

SciTech Connect (OSTI)

A method on electromagnetic mode analysis in overmoded structure terahertz source is studied in this paper. This mode analysis method is based on Fourier-Bessel series and the particle-in-cell simulation. The result of mode analysis shows that there are TM{sub 02} and TM{sub 03} modes present in the waveguide motivated by mode change in the discontinuity. The mode content keeps stable when the device starts to work. The magnetic field and the voltage of beam do not change the mode content to some extent. The parameters of diode affect the mode content significantly.

Li, Xiaoze; Xiao, Renzhen; Wang, Guangqiang; Zhang, Lijun; Zhang, Yuchuan; Ye, Hu [Northwest Institute of Nuclear Technology, P. O. Box 69-1, Xi'an 710024 (China)] [Northwest Institute of Nuclear Technology, P. O. Box 69-1, Xi'an 710024 (China); Wang, Jianguo [Northwest Institute of Nuclear Technology, P. O. Box 69-1, Xi'an 710024 (China) [Northwest Institute of Nuclear Technology, P. O. Box 69-1, Xi'an 710024 (China); School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an 710049 (China)

2013-08-15T23:59:59.000Z

62

Radiative Decay Modes of the Muon  

Science Journals Connector (OSTI)

A 5-in. freon bubble chamber was used to search for the following decay modes of the ?+ meson: (1)?+?e++?, (2)?+?e++e-+e+, (3)?+?e++?0+?0+?, (4)?+?e++?0+?0+e++e-. Two exposures were made at the Carnegie Institute of Technology synchrocyclotron. A total of 200 000 pictures were taken yielding 3.3105 ?+ meson decays.A total of 3105 ?+ decays were examined for mode (1). No decays consistent with this mode were found. The upper limit on the branching ratio Rrad was found to be Rrad=(?+?e++?)(?+?e++?0+?0)<2.510-5.A total of 3.3105 ?+ decays were scanned for mode (2) and no such decays were observed. The limit on the branching ratio R3e was found to be R3e=(?+?e++e-+e+)(?+?e++?0+?0)<410-6.The internal bremsstrahlung rate (mode 3) was measured for two values of E?0 (the minimum photon energy detected). The results were RIB=(?+?e++?0+?0+?)(?+?e++?0+?0), RIB=(1.40.4)10-2,E?0=10Mev, RIB=(3.31.3)10-3,E?0=20Mev.The rate of internal conversion of internal bremsstrahlung [mode (4)] was found to be RIC=(?+?e++?0+?0+e++e-)(?+?e++?0+?0)=(2.21.5)10-5,E0=10Mev, where E0 is the minimum energy of the internally converted ? ray.A summary is given of previous experiments on these decay modes and results are discussed with special reference to the intermediate boson scheme of weak four-fermion interactions.

R. R. Crittenden; W. D. Walker; J. Ballam

1961-03-15T23:59:59.000Z

63

Single transverse mode selectively oxidized vertical cavity lasers  

SciTech Connect (OSTI)

Vertical cavity surface emitting lasers (VCSELs) which operate in multiple transverse optical modes have been rapidly adopted into present data communication applications which rely on multi-mode optical fiber. However, operation only in the fundamental mode is required for free space interconnects and numerous other emerging VCSEL applications. Two device design strategies for obtaining single mode lasing in VCSELs based on mode selective loss or mode selective gain are reviewed and compared. Mode discrimination is attained with the use of a thick tapered oxide aperture positioned at a longitudinal field null. Mode selective gain is achieved by defining a gain aperture within the VCSEL active region to preferentially support the fundamental mode. VCSELs which exhibit greater than 3 mW of single mode output power at 850 nm with mode suppression ratio greater than 30 dB are reported.

CHOQUETTE,KENT D.; GEIB,KENT M.; BRIGGS,RONALD D.; ALLERMAN,ANDREW A.; HINDI,JANA JO

2000-04-26T23:59:59.000Z

64

2007 Raj JainCSE571SWashington University in St. Louis Modes ofModes of  

E-Print Network [OSTI]

, CFB, CTR 2. Privacy+Integrity 3. DES Attacks 4. 3DES and its design Ref: Chapter 4 of textbook. #12. Electronic Code Book (ECB) 2. Cipher Block Chaining (CBC) 3. Cipher Feedback Mode (CFB) 4. Output Feedback be used #12;6-10 ©2007 Raj JainCSE571SWashington University in St. Louis kk--Bit Cipher Feedback Mode (CFB

Jain, Raj

65

Detecting individual gravity modes in the Sun  

E-Print Network [OSTI]

Many questions are still open regarding the structure and the dynamics of the solar core. By constraining more this region in the solar evolution models, we can reduce the incertitudes on some physical processes and on momentum transport mechanisms. A first big step was made with the detection of the signature of the dipole-gravity modes in the Sun, giving a hint of a faster rotation rate inside the core. A deeper analysis of the GOLF/SoHO data unveils the presence of a pattern of peaks that could be interpreted as dipole gravity modes. In that case, those modes can be characterized, thus bringing better constraints on the rotation of the core as well as some structural parameters such as the density at these very deep layers of the Sun interior.

Garcia, R A; Eff-Darwich, A; Garrido, R; Jimenez, A; Mathis, S; Moya, A; Palle, P L; Regulo, C; Salabert, D; Suarez, J C; Turck-Chieze, S

2009-01-01T23:59:59.000Z

66

Contained Modes In Mirrors With Sheared Rotation  

SciTech Connect (OSTI)

In mirrors with E B rotation, a fixed azimuthal perturbation in the lab frame can appear as a wave in the rotating frame. If the rotation frequency varies with radius, the plasma-frame wave frequency will also vary radially due to the Doppler shift. A wave that propagates in the high rotation plasma region might therefore be evanescent at the plasma edge. This can lead to radially localized Alfven eigenmodes with high azimuthal mode numbers. Contained Alfven modes are found both for peaked and non-peaked rotation profiles. These modes might be useful for alpha channeling or ion heating, as the high azimuthal wave number allows the plasma wave frequency in the rotating frame to exceed the ion cyclotron frequency. __________________________________________________

Abraham J. Fetterman and Nathaniel J. Fisch

2010-10-08T23:59:59.000Z

67

Stabilization of Ballooning Modes by Nonparaxial Cells  

SciTech Connect (OSTI)

An analysis is made of the effect of high-curvature stabilizing nonparaxial elements (cells) on the MHD plasma stability in open confinement systems and in confinement systems with closed magnetic field lines. It is shown that the population of particles trapped in such cells has a stabilizing effect not only on convective (flute) modes but also on ballooning modes, which govern the maximum possible {beta} value. In the kinetic approach, which distinguishes between the effects of trapped and passing particles, the maximum possible {beta} values consistent with stability can be much higher than those predicted by the MHD model.

Arsenin, V.V.; Zvonkov, A.V.; Skovoroda, A.A. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, pl. Kurchatova 1, Moscow, 123182 (Russian Federation)

2005-01-15T23:59:59.000Z

68

Self-Similar Modes of Coherent Diffusion  

E-Print Network [OSTI]

Self-similar solutions of the coherent diffusion equation are derived and measured. The set of real similarity solutions is generalized by the introduction of a nonuniform phase surface, based on the elegant Gaussian modes of optical diffraction. In an experiment of light storage in a gas of diffusing atoms, a complex initial condition is imprinted, and its diffusion dynamics is monitored. The self-similarity of both the amplitude and the phase pattern is demonstrated, and an algebraic decay associated with the mode order is measured. Notably, as opposed to a regular diffusion spreading, a self-similar contraction of a special subset of the solutions is predicted and observed.

O. Firstenberg; P. London; D. Yankelev; R. Pugatch; M. Shuker; N. Davidson

2010-08-16T23:59:59.000Z

69

Nonlinear mode coupling analysis in the Tevatron  

SciTech Connect (OSTI)

Increased demand for higher luminosities from Fermilab proton-antiproton collider requires higher intensities and increased number of bunches. The performance of existing 6 x 6 and the proposed 36 x 36 collider is often limited by the non-linear effects arising from beam-beam interactions, in particular for high intensity beams. The tune shifts and spread from increased long range interactions combined with higher order multipoles complicates the frequency spectrum of the particle motions. TEAPOT simulation program is used to generate turn by turn data that could be used in the nonlinear mode spectrums analysis. Bispectral mode analysis is discussed.

Assadi, S.; Mishra, C.S.

1995-08-01T23:59:59.000Z

70

Modes of Operation: Der Cipher Feedback Steffen Reith  

E-Print Network [OSTI]

Modes of Operation: Der Cipher Feedback Mode (CFB) Steffen Reith 7. Mai 2005 Der CFB-Mode wird Shiftr Bits Shift ic r Bitsr Bits rn n r n n r r Der CFB-Mode 1 Dies ist mit Hilfe der Abbildung leicht

Vollmer, Heribert

71

Head-Tail Modes for Strong Space Charge  

SciTech Connect (OSTI)

Head-tail modes are described here for the space charge tune shift significantly exceeding the synchrotron tune. General equation for the modes is derived. Spatial shapes of the modes, their frequencies, and coherent growth rates are explored. The Landau damping rates are also found. Suppression of the transverse mode coupling instability by the space charge is explained.

Burov, Alexey

2008-12-01T23:59:59.000Z

72

Mode testing via the excess mass estimate  

Science Journals Connector (OSTI)

......right when b i = w i + 1. For the new combined mode rede fi ne the quantities a i and b i as in (A1) except that we...outer bracketing minimisers ' in place of w i and w i + 1. Then rede fi ne E i as E i = P b i a i { f (x) ? l i } + dx, where......

N. I. Fisher; J. S. Marron

2001-06-01T23:59:59.000Z

73

Do red giants have short mode lifetimes?  

E-Print Network [OSTI]

We show evidence that the red giant star ksi Hya has an oscillation mode lifetime, tau, of about 2 days significantly shorter than predicted by theory (tau = 17 days, Houdek & Gough 2002). If this is a general trend of red giants it would limit the prospects of asteroseismology on these stars because of poor coherence of the oscillations.

D. Stello; H. Kjeldsen; T. R. Bedding; D. Buzasi

2005-10-18T23:59:59.000Z

74

Thermionic converter in load-switching mode  

SciTech Connect (OSTI)

An electrical equivalent circuit is proposed for a thermionic electrogenerating element. It is suitable for calculation of transients in load-switching mode. Formulas are given for estimating circuit parameters. A sample numerical calculation is given for the transient between no-load and short-circuit regimes. The results may be employed to identify experimental data in the frequency domain.

Mendel'baum, M.A.; Es'kov, V.D.

1983-01-01T23:59:59.000Z

75

HYDROGEN LOCAL VIBRATIONAL MODES IN COMPOUND SEMICONDUCTORS  

E-Print Network [OSTI]

HYDROGEN LOCAL VIBRATIONAL MODES IN COMPOUND SEMICONDUCTORS M.D. MCCLUSKEY* University) spectroscopy of hydrogen and deuterium in GaP, AlSb, ZnSe, and GaN has provided important information about the structures of dopant- hydrogen complexes and their interaction with the host lattice. In GaN:Mg, for example

McCluskey, Matthew

76

Triangular-profile single-mode fiber  

Science Journals Connector (OSTI)

A low-loss triangular-profile single-mode fiber is reported. The fiber loss at 1.31.55-?m wavelengths is below 0.4 dB/km, and its zero-chromatic-dispersion wavelength is 1.402 ?m.

Saifi, M A; Cohen, L G; Stone, J; Jang, S J

1982-01-01T23:59:59.000Z

77

Pulses inside the pulse mode of operation at RF Gun  

E-Print Network [OSTI]

Pulses inside the pulse mode of operation at RF Gun V. Vogel, V. Ayvazyan, K. Floettmann, D. Lipka a PiP mode of operation at RF Gun · What we need, to operate FLASH in the PiP mode · PiP study-Universitaet Bochum) Alternative: SC GUN DC GUN Cold GUN in PiP mode Cold Traveling wave GUN Why we need a PiP mode

78

Self-consistent study of the alpha particle driven TAE mode  

SciTech Connect (OSTI)

The interaction of high energy particles with an Alfven eigenmode is investigated self-consistently by using a realistic kinetic dispersion relation. All important poloidal mode numbers and their radial mode profiles as calculated with the NOVA-K code are included. A Hamiltonian guiding center code is used to simulate the alpha particle motion. The numerical simulations include particle orbit width, nonlinear particle dynamics and the effects of the modes on the particles. Modification of the particle distribution leading to mode saturation is observed. Particle loss is limited to devices in which the alpha particle gyro radius is a significant fraction of the minor radius.

Wu, Y.; White, R.B.

1994-04-01T23:59:59.000Z

79

Mode-synthesizing atomic force microscopy and mode-synthesizing sensing  

DOE Patents [OSTI]

A method of analyzing a sample that includes applying a first set of energies at a first set of frequencies to a sample and applying, simultaneously with the applying the first set of energies, a second set of energies at a second set of frequencies, wherein the first set of energies and the second set of energies form a multi-mode coupling. The method further includes detecting an effect of the multi-mode coupling.

Passain, Ali; Thundat, Thomas George; Tetard, Laurene

2014-07-22T23:59:59.000Z

80

Electron acceleration by Z-mode and whistler-mode waves  

SciTech Connect (OSTI)

We carried out a series of particle simulations to study electron acceleration by Z-mode and whistler-mode waves generated by an electron ring distribution. The electron ring distribution leads to excitations of X-mode waves mainly in the perpendicular direction, Z-mode waves in the perpendicular and parallel directions, and whistler-mode waves mainly in the parallel direction. The parallel Z- and whistler-mode waves can lead to an effective acceleration of ring electrons. The electron acceleration is mainly determined by the wave amplitude and phase velocity, which in turn is affected by the ratio of electron plasma to cyclotron frequencies. For the initial kinetic energy ranging from 100 to 500 keV, the peak energy of the accelerated electrons is found to reach 28 times the initial kinetic energy. We further study the acceleration process by test-particle calculations in which electrons interact with one, two, or four waves. The electron trajectories in the one-wave case are simple diffusion curves. In the multi-wave cases, electrons are accelerated simultaneously by counter-propagating waves and can have a higher final energy.

Lee, K. H. [Institute of Space Science, National Central University, Zhongli, Taiwan (China)] [Institute of Space Science, National Central University, Zhongli, Taiwan (China); Omura, Y. [Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto (Japan)] [Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto (Japan); Lee, L. C. [Institute of Space Science, National Central University, Zhongli, Taiwan (China) [Institute of Space Science, National Central University, Zhongli, Taiwan (China); Institute of Earth Science, Academia Sinica, Nankang, Taiwan (China)

2013-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

OBSERVED DAMPING OF THE SLOW MAGNETOACOUSTIC MODE  

SciTech Connect (OSTI)

Spectroscopic and stereoscopic imaging observations of slow magnetoacoustic wave propagation within a coronal loop are investigated to determine the decay length scale of the slow magnetoacoustic mode in three dimensions and the density profile within the loop system. The slow wave is found to have an e-folding decay length scale of 20,000{sup +4000}{sub -3000} km with a uniform density profile along the loop base. These observations place quantitative constraints on the modeling of wave propagation within coronal loops. Theoretical forward modeling suggests that magnetic field line divergence is the dominant damping factor and thermal conduction is insufficient, given the observed parameters of the coronal loop temperature, density, and wave mode period.

Marsh, M. S.; Walsh, R. W. [Jeremiah Horrocks Institute for Astrophysics and Supercomputing, University of Central Lancashire, Preston PR1 2HE (United Kingdom); De Moortel, I., E-mail: mike.s.marsh@gmail.com, E-mail: mmarsh@uclan.ac.uk [School of Mathematics and Statistics, University of St Andrews, St Andrews KY16 9SS (United Kingdom)

2011-06-20T23:59:59.000Z

82

Geodesic stability, Lyapunov exponents and quasinormal modes  

E-Print Network [OSTI]

Geodesic motion determines important features of spacetimes. Null unstable geodesics are closely related to the appearance of compact objects to external observers and have been associated with the characteristic modes of black holes. By computing the Lyapunov exponent, which is the inverse of the instability timescale associated with this geodesic motion, we show that, in the eikonal limit, quasinormal modes of black holes in any dimensions are determined by the parameters of the circular null geodesics. This result is independent of the field equations and only assumes a stationary, spherically symmetric and asymptotically flat line element, but it does not seem to be easily extendable to anti-de Sitter spacetimes. We further show that (i) in spacetime dimensions greater than four, equatorial circular timelike geodesics in a Myers-Perry black hole background are unstable, and (ii) the instability timescale of equatorial null geodesics in Myers-Perry spacetimes has a local minimum for spacetimes of dimension d > 5.

Vitor Cardoso; Alex S. Miranda; Emanuele Berti; Helvi Witek; Vilson T. Zanchin

2009-03-12T23:59:59.000Z

83

??? Decay Mode of Neutral K Mesons  

Science Journals Connector (OSTI)

The decay K??++?-+?, ??e++e- has been observed in the film of the UCRL 72-in. hydrogen bubble chamber exposed to a beam of 1325-MeV/c momentum negative pions. This event unambiguously fits only the decay mode K??+?+?, but because the K's life span is almost exactly one K10 lifetime it is impossible to say whether it is a direct ??? or inner bremsstrahlung accompanying normal K10?2? decay.

D. Stern

1962-10-01T23:59:59.000Z

84

Stabilizing windings for tilting and shifting modes  

DOE Patents [OSTI]

This invention relates to passive conducting loops for stabilizing a plasma ring against unstable tilting and/or shifting modes. To this end, for example, plasma ring in a spheromak is stabilized by a set of four figure-8 shaped loops having one pair on one side of the plasma and one pair on the other side with each pair comprising two loops whose axes are transverse to each other.

Jardin, Stephen C. (Princeton, NJ); Christensen, Uffe R. (Princeton, NJ)

1984-01-01T23:59:59.000Z

85

Resistive internal kink modes in a differentially rotating cylindrical plasma  

SciTech Connect (OSTI)

The resistive internal kink modes in a differentially rotating cylindrical plasma column are studied. It is shown that the Velikhov effect, which causes the magnetorotational instability in astrophysics, contributes to the magnetic hill/well and thereby enhances or suppresses these modes, depending on the character of radial profile of the rotation frequency. It is pointed out that, in the case of unfavorable rotation frequency profile, such a rotation-induced magnetic hill can exceed the hill effect due to the plasma pressure gradient. Under this condition, there appears a new variety of resistive-interchange modes, which are referred to as rotational modes. On the other hand, for a favorable rotation frequency profile, the Velikhov effect suppresses the resistive-interchange modes. These results concern the m>1 modes, where m is the poloidal mode number. In the case of perturbations with m=1, the favorable rotation frequency profile leads to decreasing the growth rate of the reconnecting mode.

Mikhailovskii, A. B.; Lominadze, J. G.; Galvao, R. M. O.; Churikov, A. P.; Erokhin, N. N.; Konovalov, S. V.; Smolyakov, A. I.; Tsypin, V. S. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); Kharadze Abastumani National Astrophysical Observatory, 2a, Kazbegi Ave., Tbilisi 0160 (Georgia); Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo (Brazil) and Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil); Syzran Branch of Samara Technical University, 45, Sovetskaya Str., Syzran, Samara Region 446001 (Russian Federation); Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation); University of Saskatchewan, 116 Science place, Saskatoon, Saskatchewan S7N 5E2 (Canada) and Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation); Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil)

2007-11-15T23:59:59.000Z

86

Diagnostic for two-mode variable valve activation device  

DOE Patents [OSTI]

A method is provided for diagnosing a multi-mode valve train device which selectively provides high lift and low lift to a combustion valve of an internal combustion engine having a camshaft phaser actuated by an electric motor. The method includes applying a variable electric current to the electric motor to achieve a desired camshaft phaser operational mode and commanding the multi-mode valve train device to a desired valve train device operational mode selected from a high lift mode and a low lift mode. The method also includes monitoring the variable electric current and calculating a first characteristic of the parameter. The method also includes comparing the calculated first characteristic against a predetermined value of the first characteristic measured when the multi-mode valve train device is known to be in the desired valve train device operational mode.

Fedewa, Andrew M

2014-01-07T23:59:59.000Z

87

Zero Net Energy Myths and Modes of Thought  

E-Print Network [OSTI]

mypp.html. . (2009). "Net-Zero Energy CommercialZeroNetEnergyMythsandModesofThought NicholasB. AC02? 05CH11231. Page | i Zero Net Energy Myths and Modes of

Rajkovich, Nicholas B.

2010-01-01T23:59:59.000Z

88

Cladding-pumped passive harmonically mode-locked fiber laser  

Science Journals Connector (OSTI)

A passive harmonically mode-locked fiber laser cladding pumped by a broad-area diode-laser array is described. Harmonic mode locking is obtained in a frequency range from 33.3 to 128.6...

Fermann, M E; Minelly, J D

1996-01-01T23:59:59.000Z

89

Sandia National Laboratories: BES Web Highlight: Single-mode...  

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

ClimateECEnergyEnergy EfficiencyBES Web Highlight: Single-mode gallium nitride nanowire lasers BES Web Highlight: Single-mode gallium nitride nanowire lasers "Solid-state Lighting:...

90

Designation of Mode Mix in Orthotropic Composite Delamination Problems  

Science Journals Connector (OSTI)

In interfacial fracture modeling of composite delamination, mode mix is typically specified in terms of energy release rates. Other near-tip quantities can be used to designate mode mix, however. This paper consi...

S.H. Narayan; J.L. Beuth

91

Stabilization of Resistive Kink Modes in the Tokamak  

Science Journals Connector (OSTI)

Optimized current profiles are shown to be capable of providing simultaneous stability against all resistive kink modes in the tokamak.

A. H. Glasser; H. P. Furth; P. H. Rutherford

1977-01-31T23:59:59.000Z

92

Viscoelastic modes in a strongly coupled, cold, magnetized dusty plasma  

SciTech Connect (OSTI)

A generalized hydrodynamical model has been used to study the low frequency modes in a strongly coupled, cold, magnetized dusty plasma. Such plasmas exhibit elastic properties due to the strong correlations among dust particles and the tensile stresses imparted by the magnetic field. It has been shown that longitudinal compressional Alfven modes and elasticity modified transverse shear mode exist in such a medium. The features of these collective modes are established and discussed.

Banerjee, Debabrata; Mylavarapu, Janaki Sita; Chakrabarti, Nikhil [Saha Institute of Nuclear Physics, I/AF Bidhannagar, Calcutta 700 064 (India)

2010-11-15T23:59:59.000Z

93

Skyrmion vibration modes within the rational map ansatz  

SciTech Connect (OSTI)

We study the vibration modes of the Skyrme model within the rational map ansatz. We show that the vibrations of the radial profiles and the rational maps are decoupled and we consider explicitly the cases B=1, B=2, and B=4. We then compare our results with the vibration modes obtained numerically by Barnes et al. and show that qualitatively the rational map reproduces the vibration modes obtained numerically but that the vibration frequencies of these modes do not match very well.

Lin, W. T.; Piette, B. [Department of Mathematical Sciences, University of Durham, Durham, DH1 3LE (United Kingdom)

2008-06-15T23:59:59.000Z

94

Skyrmion Vibration Modes within the Rational Map Ansatz  

E-Print Network [OSTI]

We study the vibration modes of the Skyrme model within the rational map ansatz. We show that the vibrations of the radial profiles and the rational maps are decoupled and we consider explicitly the case B=1, B=2 and B=4. We then compare our results with the vibration modes obtained numerically by Barnes et al. and show that qualitatively the rational map reproduces the vibration modes obtained numerically but that the vibration frequencies of these modes do not match very well.

W. T. Lin; B. Piette

2008-04-30T23:59:59.000Z

95

The Influence of Topology Changes on Inter-area Oscillation Modes and Mode Shapes  

SciTech Connect (OSTI)

The topology of a power grid network is a piece of critical information for power grid operations. Different power grid topologies can change grid characteristics, inter-area oscillation modes, mode shapes, and even the robustness of the power system. This paper presents some preliminary study results, based on an approved WECC operating case and a modified low damping WECC system, to show the impact of topology changes resulting from N-1 contingencies on power system modes and mode shapes. The results show that topology changes can have very different impact on modal properties in a power system: some result in unstable situation, while others can improve small signal stability. For the former, the studies show about 4.5% damping reduction, so 5% damping margin would be required to ensure the system can sustain the contingencies. For the latter, those topology changes could be used as a control method to improve small signal stability. Mode shapes normally do not change when there is an N-1 topology change. These observations suggest that the inclusion of topological information is useful for improving the accuracy and effectiveness of power system control schemes.

Chen, Yousu; Fuller, Jason C.; Diao, Ruisheng; Zhou, Ning; Huang, Zhenyu; Tuffner, Francis K.

2011-10-17T23:59:59.000Z

96

Normal modes, virtual modes, and alternative representations in the theory of surface?duct sound propagation  

Science Journals Connector (OSTI)

This paper presents a theoretical study of sound propagation in an ocean?surface duct. It deals with several aspects of the theory from a point of view which has not heretofore been taken in the analyses of this problem. The model used to describe a duct assumes the ocean surface to be smooth and the square of the refractive index to be bilinear. Alternative representations of the sound field excited by a point source are derived the two playing the most significant role in this paper being the residue series and the normal?mode representation. It is shown that the depth functions of the residue series do not form a complete set as those of a normal?mode representation must and that the normal?mode spectrum is continuous rather than discrete. The completeness properties of the normal?mode functions are then utilized in a study of the energy?trapping capabilities of the duct. In this connection virtual modes are introduced and shown to lead naturally to the derivation of a leakage coefficient characteristic of the exponential leakage of energy out of the duct with increasing range. In addition a cutoff?frequency criterion useful in determining when a surface duct can trap energy is derived.

Frank M. Labianca

1973-01-01T23:59:59.000Z

97

Power consumption optimization in multi-mode mobile relay  

E-Print Network [OSTI]

Power consumption optimization in multi-mode mobile relay C´edric L´evy-Bencheton #1 , Guillaume-mode can reduce terminal power consumption. Software Defined Radio is an enabler towards multi through relays, is another solution to reduce power consumption. We look at multi-mode relaying, where

Paris-Sud XI, Université de

98

Theory of passive harmonic mode-locking using waveguide arrays  

E-Print Network [OSTI]

laser," Opt. Lett. 23, 123-125 (1998). 3. M. E. Fermann and J. D. Minelly, "Cladding-pumped passive theoretical treatment is given of the phe- nomenon of harmonic mode-locking in a laser cavity mode Optical Society of America OCIS codes: (140.4050) Mode-locked lasers; (060.5530) Pulse propagation

99

Inflation, Symmetry, and B-Modes  

E-Print Network [OSTI]

We examine the role of using symmetry and effective field theory in inflationary model building. We describe the standard formulation of starting with an approximate shift symmetry for a scalar field, and then introducing corrections systematically in order to maintain control over the inflationary potential. We find that this leads to models in good agreement with recent data. On the other hand, there are attempts in the literature to deviate from this paradigm by envoking other symmetries and corrections. In particular: in a suite of recent papers, several authors have made the claim that standard Einstein gravity with a cosmological constant and a massless scalar carries conformal symmetry. They further claim that such a theory carries another hidden symmetry; a global SO(1,1) symmetry. By deforming around the global SO(1,1) symmetry, they are able to produce a range of inflationary models with asymptotically flat potentials, whose flatness is claimed to be protected by these symmetries. These models tend to give rise to B-modes with small amplitude. Here we explain that these authors are merely introducing a redundancy into the description, not an actual conformal symmetry. Furthermore, we explain that the only real (global) symmetry in these models is not at all hidden, but is completely manifest when expressed in the Einstein frame; it is in fact the shift symmetry of a scalar field. When analyzed systematically as an effective field theory, deformations do not generally produce asymptotically flat potentials and small B-modes, but other types of potentials with B-modes of large amplitude; nicely compatible with recent BICEP2 data. Such simple models typically also produce the observed red spectral index, Gaussian fluctuations, etc. In short: simple models of inflation, organized by expanding around a shift symmetry, are in excellent agreement with recent data.

Mark P. Hertzberg

2014-03-20T23:59:59.000Z

100

Single-mode fiber, velocity interferometry  

SciTech Connect (OSTI)

In this paper, we describe a velocity interferometer system based entirely on single-mode fiber optics. This paper includes a description of principles used in developing the single-mode velocity interferometry system (SMV). The SMV design is based on polarization-insensitive components. Polarization adjusters are included to eliminate the effects of residual birefringence and polarization dependent losses in the interferometers. Characterization measurements and calibration methods needed for data analysis and a method of data analysis are described. Calibration is performed directly using tunable lasers. During development, we demonstrated its operation using exploding-foil bridge-wire fliers up to 200 m/s. In a final test, we demonstrated the SMV in a gas gun experiment up to 1.2 km/sec. As a basis for comparison in the gas gun experiment, we used another velocimetry technique that is also based on single-mode fiber optics: photonic Doppler velocimetry (PDV). For the gas gun experiment, we split the light returned from a single target spot and performed a direct comparison of the homodyne (SMV) and heterodyne (PDV) techniques concurrently. The two techniques had a negligible mean difference and a 1.5% standard deviation in the one-dimensional shock zone. Within one interferometer delay time after a sudden Doppler shift, a SMV unencumbered by multimode-fiber dispersion exhibits two color beats. These beats have the same period as PDV beats--this interference occurs between the ''recently'' shifted and ''formerly unshifted'' paths within the interferometer. We believe that recognizing this identity between homodyne and heterodyne beats is novel in the shock-physics field. SMV includes the conveniences of optical fiber, while removing the time resolution limitations associated with the multimode delivery fiber.

Krauter, K. G.; Jacobson, G. F.; Patterson, J. R.; Nguyen, J. H.; Ambrose, W. P. [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore California 94551 (United States)

2011-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" from the National Library of EnergyBeta (NLEBeta).
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101

NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 FAILURE MODES AND EFFECTS ANALYSIS  

E-Print Network [OSTI]

NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 NSTX FAILURE MODES AND EFFECTS ANALYSIS (FMEA) Revision 10 Dated: November 2014 Prepared By: Name/WBS Signature Name: ________________________________________________ Ron Strykowsky, NSTX Upgrade Project Manager #12;NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71

Princeton Plasma Physics Laboratory

102

Effect of Trapped Energetic Particles on the Resistive Wall Mode  

SciTech Connect (OSTI)

A stability analysis for the resistive wall mode is studied in the presence of trapped energetic particles (EPs). When the EPs' beta exceeds a critical value, a fishbonelike bursting mode (FLM) with an external kink eigenstructure can exist. This offers the first analytic interpretation of the experimental observations [Phys. Rev. Lett. 103, 045001 (2009)]. The mode-particle resonances for the FLM and the q=1 fishbone occur in different regimes of the precession frequency of EPs. In certain ranges of the plasma rotation speed and the EPs' beta, a mode conversion can occur between the resistive wall mode and FLM.

Hao, G. Z.; Wang, A. K.; Qiu, X. M. [Southwestern Institute of Physics, Post Office Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

2011-07-01T23:59:59.000Z

103

Damping of unwanted modes in SRF deflecting/crabbing cavities  

SciTech Connect (OSTI)

As deflecting and crab cavities do not use the fundamental acceleration mode for their operation, the spectrum of unwanted modes is significantly different from that of accelerating cavities. The fundamental acceleration mode is now unwanted and can cause energy spread in the beam; in addition this mode frequency is often close to or lower than that of the deflecting mode, making it difficult to damp. This is made more complex in some of the compact crab cavities as there small beampipes often attenuate the fields very sharply. In addition in some crab cavities there can be an orthogonal transverse mode similar to the deflecting mode, known as the same order mode. The degeneracy of these modes must be split by polarising the cavity and if the polarisation is not large enough, dampers should be placed at either an electric or magnetic field null of the crabbing mode to effectively damp the unwanted polarisation. Various concepts for dealing with unwanted modes in various SRF deflecting cavities will be reviewed.

Burt, Graeme [University of Lancaster (United Kingdom); Wang, Haipeng [JLAB, Newport News, VA (United States)

2014-01-01T23:59:59.000Z

104

Multi-mode ultrasonic welding control and optimization  

DOE Patents [OSTI]

A system and method for providing multi-mode control of an ultrasonic welding system. In one embodiment, the control modes include the energy of the weld, the time of the welding process and the compression displacement of the parts being welded during the welding process. The method includes providing thresholds for each of the modes, and terminating the welding process after the threshold for each mode has been reached, the threshold for more than one mode has been reached or the threshold for one of the modes has been reached. The welding control can be either open-loop or closed-loop, where the open-loop process provides the mode thresholds and once one or more of those thresholds is reached the welding process is terminated. The closed-loop control provides feedback of the weld energy and/or the compression displacement so that the weld power and/or weld pressure can be increased or decreased accordingly.

Tang, Jason C.H.; Cai, Wayne W

2013-05-28T23:59:59.000Z

105

Enhancing The Mode Conversion Efficiency In JET Plasmas With Multiple Mode Conversion Layers  

SciTech Connect (OSTI)

The constructive interference effect described by Fuchs et al. [1] shows that the mode conversion and thereby the overall heating efficiency can be enhanced significantly when an integer number of fast wave wavelengths can be folded in between the high field side fast wave cutoff and the ion-ion hybrid layer(s) at which the ion Bernstein or ion cyclotron waves are excited. This effect was already experimentally identified in ({sup 3}He)-D plasmas [2] and was recently tested in ({sup 3}He)-H JET plasmas. The latter is an 'inverted' scenario, which differs significantly from the ({sup 3}He)-D scenarios since the mode-conversion layer is positioned between the low field side edge of the plasma and the ion-cyclotron layer of the minority {sup 3}He ions (whereas the order in which a wave entering the plasma from the low field side encounters these layers is inverted in a 'regular' scenario), and because much lower {sup 3}He concentrations are needed to achieve the mode-conversion heating regime. The presence of small amounts of {sup 4}He and D in the discharges gave rise to an additional mode conversion layer on top of the expected one associated with {sup 3}He-H, which made the interpretation of the results more complex but also more interesting: Three different regimes could be distinguished as a function of X[{sup 3}He], and the differing dynamics at the various concentrations could be traced back to the presence of these two mode conversion layers and their associated fast wave cutoffs. Whereas (1-D and 2-D) numerical modeling yields quantitative information on the RF absorptivity, recent analytical work by Kazakov [3] permits to grasp the dominant underlying wave interaction physics.

Van Eester, D.; Lerche, E.; Ongena, J. [LPP-ERM/KMS, Association Euratom-'Belgian State', TEC Partner, Brussels (Belgium); Johnson, T.; Hellsten, T. [Fusion Plasma Physics, Association Euratom-VR, KTH, Stockholm (Sweden); Mayoral, M.-L.; Beaumont, P.; Blackman, T.; Brennan, D.; Brett, A.; Coffey, I.; Coyne, A.; Felton, R.; Giroud, C.; Jacquet, P.; Kiptily, V.; Knipe, S.; Monakhov, I.; Noble, C.; Pangioni, L. [Euratom-CCFE Fusion Association, Culham Science Centre (United Kingdom)

2011-12-23T23:59:59.000Z

106

Onset and Saturation of a Non-resonant Internal Mode in NSTX and Implications For AT Modes in ITER  

SciTech Connect (OSTI)

Motivated by experimental observations of apparently triggerless tearing modes, we have performed linear and nonlinear MHD analysis showing that a non-resonant mode with toroidal mode number n = 1 can develop in the National Spherical Torus eXperiment (NSTX) at moderate normalized ?N when the shear is low and the central safety factor q0 is close to but greater than one. This mode, which is related to previously identified infernal modes, will saturate and persist, and can develop poloidal mode number m = 2 magnetic islands in agreement with experiments. We have also extended this analysis by performing a free-boundary transport simulation of an entire discharge and showing that, with reasonable assumptions, we can predict the time of mode onset. __________________________________________________

J.A. Breslau, M.S. Chance, J. Chen, G.Y. Fu, S,. Gerhardt, N. Gorelenkov, S.C. Jardin and J. Manickam

2011-08-01T23:59:59.000Z

107

Collisional damping of the geodesic acoustic mode  

SciTech Connect (OSTI)

The frequency and damping rate of the geodesic acoustic mode (GAM) is revisited by using a gyrokinetic model with a number-conserving Krook collision operator. It is found that the damping rate of the GAM is non-monotonic as the collision rate increases. At low ion collision rate, the damping rate increases linearly with the collision rate; while as the ion collision rate is higher than v{sub ti}/R, where v{sub ti} and R are the ion thermal velocity and major radius, the damping rate decays with an increasing collision rate. At the same time, as the collision rate increases, the GAM frequency decreases from the (7/4+{tau})v{sub ti}/R to (1+{tau})v{sub ti}/R, where {tau} is the ratio of electron temperature to ion temperature.

Gao Zhe [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

2013-03-15T23:59:59.000Z

108

Towards a detection of individual g modes in the Sun  

E-Print Network [OSTI]

Since the detection of the asymptotic properties of the dipole gravity modes in the Sun, the quest to find the individual gravity modes has continued. A deeper analysis of the GOLF/SoHO data unveils the presence of a pattern of peaks that could be interpreted as individual dipole gravity modes. The computed collapsed spectrum -around these candidate modes- uncovers the presence of a quasi constant frequency splitting, in contrast with regions where no g modes are expected in which the collapsogram gives random results. Besides, the same technique applied to VIRGO/SoHO unveils some common signals between both power spectra. Thus, we can identify and characterize the modes, for example, with their central frequency and splittings. This would open the path towards new investigations to better constrain the solar core.

Garcia, R A; Eff-Darwich, A; Garrido, R; Jimenez, A; Mathis, S; Mathur, S; Moya, A; Palle, P L; Regulo, C; Salabert, D; Suarez, J C; Turck-Chieze, S

2010-01-01T23:59:59.000Z

109

A current driven electromagnetic mode in sheared and toroidal configurations  

E-Print Network [OSTI]

The induced electric field in a tokamak drives a parallel electron current flow. In an inhomogeneous, finite beta plasma, when this electron flow is comparable to the ion thermal speed, the Alfven mode wave solutions of the electromagnetic gyrokinetic equation can become nearly purely growing kink modes. Using the new "low-flow" version of the gyrokinetic code GS2 developed for momentum transport studies [Barnes et al 2013 Phys. Rev. Lett. 111, 055005], we are able to model the effect of the induced parallel electric field on the electron distribution to study the destabilizing influence of current on stability. We identify high mode number kink modes in GS2 simulations and make comparisons to analytical theory in sheared magnetic geometry. We demonstrate reassuring agreement with analytical results both in terms of parametric dependences of mode frequencies and growth rates, and regarding the radial mode structure.

Pusztai, Istvn; Parra, Felix I; Barnes, Michael

2013-01-01T23:59:59.000Z

110

Statistical Testing for Disk Encryption Modes of Mohamed Abo El-Fotouh and Klaus Diepold  

E-Print Network [OSTI]

. We are going to study ten modes of operations, five narrow-block modes (CFB, CBC, CTR, LRW and XTS

111

Optimization to reduce fuel consumption in charge depleting mode  

DOE Patents [OSTI]

A powertrain includes an internal combustion engine, a motor utilizing electrical energy from an energy storage device, and a plug-in connection. A Method for controlling the powertrain includes monitoring a fuel cut mode, ceasing a fuel flow to the engine based upon the fuel cut mode, and through a period of operation including acceleration of the powertrain, providing an entirety of propelling torque to the powertrain with the electrical energy from the energy storage device based upon the fuel cut mode.

Roos, Bryan Nathaniel; Martini, Ryan D.

2014-08-26T23:59:59.000Z

112

Circular modes for flat beams in the LHC  

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

Typically x/y optical coupling is considered as unwanted and thus suppressed; particular exclusions are electron and ionization coolers. Could some special coupled modes be effectively applied for the LHC complex? Perhaps, the answer is positive: use of the circular modes in the injectors with their transformation into planar modes in the LHC allows both the space charge and beam-beam luminosity limitations to be significantly reduced, if not practically eliminated.

Burov, A.

2013-06-01T23:59:59.000Z

113

Circular modes for flat beams in the LHC  

Science Journals Connector (OSTI)

Typically x/y optical coupling is considered as unwanted and thus suppressed; particular exclusions are electron and ionization coolers. Could some special coupled modes be effectively applied for the LHC complex? Perhaps, the answer is positive: use of the circular modes in the injectors with their transformation into planar modes in the LHC allows both the space charge and beam-beam luminosity limitations to be significantly reduced, if not practically eliminated.

A. Burov

2013-06-24T23:59:59.000Z

114

Mode trap for absorbing transverse modes of an accelerated electron beam  

DOE Patents [OSTI]

A mode trap to trap and absorb transverse modes formed by a beam in a linear accelerator includes a waveguide having a multiplicity of electrically conductive (preferably copper) irises and rings, each iris and ring including an aperture, and the irises and rings being stacked in a side-by-side, alternating fashion such that the apertures of the irises and rings are concentrically aligned. An absorbing material layer such as a dielectric is embedded in each iris and ring, and this absorbing material layer encircles, but is circumferentially spaced from its respective aperture. Each iris and ring includes a plurality of circumferentially spaced slots around its aperture and extending radially out toward its absorbing material layer.

Chojnacki, Eric P. (Woodridge, IL)

1994-01-01T23:59:59.000Z

115

Mode trap for absorbing transverse modes of an accelerated electron beam  

DOE Patents [OSTI]

A mode trap to trap and absorb transverse modes formed by a beam in a linear accelerator includes a waveguide having a multiplicity of electrically conductive (preferably copper) irises and rings, each iris and ring including an aperture, and the irises and rings being stacked in a side-by-side, alternating fashion such that the apertures of the irises and rings are concentrically aligned. An absorbing material layer such as a dielectric is embedded in each iris and ring, and this absorbing material layer encircles, but is circumferentially spaced from its respective aperture. Each iris and ring includes a plurality of circumferentially spaced slots around its aperture and extending radially out toward its absorbing material layer. 9 figs.

Chojnacki, E.P.

1994-05-31T23:59:59.000Z

116

Absorption Mode FT-ICR Mass Spectrometry Imaging. | EMSL  

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

Imaging. Absorption Mode FT-ICR Mass Spectrometry Imaging. Abstract: Fourier transform ion cyclotron resonance mass spectrometry offers the highest mass resolving power...

117

Technological features and operating modes of bottom turbines  

Science Journals Connector (OSTI)

Technological features and the startup and operation modes of a power unit consisting of an R-type turbine and a bottom turbine connected to it are considered.

L. S. Ioffe

2010-09-01T23:59:59.000Z

118

Asymmetric modes decomposition in an overmoded relativistic backward wave oscillator  

SciTech Connect (OSTI)

Most of the investigated overmoded relativistic backward wave oscillators (RBWOs) are azimuthally symmetric; thus, they are designed through two dimensional (2-D) particle-in-cell (PIC) simulations. However, 2-D PIC simulations cannot reveal the effect of asymmetric modes on beam-wave interaction. In order to investigate whether asymmetric mode competition needs to be considered in the design of overmoded RBWOs, a numerical method of determining the composition of both symmetric and asymmetric modes in three dimensional (3-D) PIC simulations is introduced in this paper. The 2-D and 3-D PIC simulation results of an X-band overmoded RBWO are analyzed. Our analysis indicates that the 2-D and 3-D PIC simulation results of our device are quite different due to asymmetric mode competition. In fact, asymmetric surface waves, especially EH{sub 11} mode, can lead to serious mode competition when electron beam propagates near the surface of slow wave structures (SWSs). Therefore, additional method of suppressing asymmetric mode competition, such as adjusting the reflections at both ends of SWSs to decrease the Q-factor of asymmetric modes, needs to be utilized in the design of overmoded RBWOs. Besides, 3-D PIC simulation and modes decomposition are essential for designing overmoded RBWOs.

Zhang, Dian; Zhang, Jun, E-mail: zhangjun@nudt.edu.cn; Zhong, Huihuang; Jin, Zhenxing; Ju, Jinchuan [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2014-09-15T23:59:59.000Z

119

Commute Mode Switching Impact Tool | Department of Energy  

Office of Environmental Management (EM)

Xcel worksheet describes the example data from the Commute Mode Switching Impact Tool. ghgcommutetool.xlsx More Documents & Publications Refrigerators and Refrigerator-Freezers...

120

PROPERTIES OF OSCILLATION MODES IN SUBGIANT STARS OBSERVED BY KEPLER  

SciTech Connect (OSTI)

Mixed modes seen in evolved stars carry information on their deeper layers that can place stringent constraints on their physics and on their global properties (mass, age, etc.). In this study, we present a method to identify and measure all oscillatory mode characteristics (frequency, height, width). Analyzing four subgiant stars, we present the first measure of the effect of the degree of mixture on the l = 1 mixed mode characteristics. We also show that some stars have measurable l = 2 mixed modes and discuss the interest of their measure to constrain the deeper layers of stars.

Benomar, O.; Bedding, T. R.; Stello, D.; White, T. R.; Kuehn, C. A. [Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Mosser, B.; Belkacem, K. [LESIA, Observatoire de Paris, CNRS UMR 8109, Universite Paris Diderot, 5 Place J. Janssen, F-92195 Meudon (France); Garcia, R. A. [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot (France); IRFU/SAp, Centre de Saclay, F-91191 Gif-sur-Yvette Cedex (France); Deheuvels, S. [Institut de Recherche en Astrophysique et Planetologie, Universite de Toulouse, UPS-OMP, CNRS, 14 Avenue Edouard Belin, F-31400 Toulouse (France); Christensen-Dalsgaard, J. [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark)

2013-04-20T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

CHARACTERIZATION OF A GEIGER-MODE AVALANCHE PHOTODIODE DETECTOR FOR  

E-Print Network [OSTI]

CHARACTERIZATION OF A GEIGER-MODE AVALANCHE PHOTODIODE DETECTOR FOR HIGH SPECTRAL RESOLUTION LIDAR................................................................................................ 20 3.2 Operation principles of an avalanche photodiode.................................. 22 3

Eloranta, Edwin W.

122

Mode Splitting for Efficient Plasmoinc Thin-film Solar Cell  

E-Print Network [OSTI]

We propose an efficient plasmonic structure consisting of metal strips and thin-film silicon for solar energy absorption. We numerically demonstrate the absorption enhancement in symmetrical structure based on the mode coupling between the localized plasmonic mode in Ag strip pair and the excited waveguide mode in silicon slab. Then we explore the method of symmetry-breaking to excite the dark modes that can further enhance the absorption ability. We compare our structure with bare thin-film Si solar cell, and results show that the integrated quantum efficiency is improved by nearly 90% in such thin geometry. It is a promising way for the solar cell.

Li, Tong; Jiang, Chun

2010-01-01T23:59:59.000Z

123

Implementing the DC Mode in Cosmological Simulations with Supercomoving Variables  

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

As emphasized by previous studies, proper treatment of the density fluctuation on the fundamental scale of a cosmological simulation volume - the 'DC mode' - is critical for accurate modeling of spatial correlations on scales ~> 10% of simulation box size. We provide further illustration of the effects of the DC mode on the abundance of halos in small boxes and show that it is straightforward to incorporate this mode in cosmological codes that use the 'supercomoving' variables. The equations governing evolution of dark matter and baryons recast with these variables are particularly simple and include the expansion factor, and hence the effect of the DC mode, explicitly only in the Poisson equation.

Gnedin, Nickolay Y.; Kravtsov, Andrey V.; Rudd, Douglas H.

2011-06-02T23:59:59.000Z

124

Novel Vortex Generator and Mode Converter for Electron Beams  

Science Journals Connector (OSTI)

A mode converter for electron vortex beams is described. Numerical simulations, confirmed by experiment, show that the converter transforms a vortex beam with a topological charge m=1 into beams closely resembling Hermite-Gaussian HG10 and HG01 modes. The converter can be used as a mode discriminator or filter for electron vortex beams. Combining the converter with a phase plate turns a plane wave into modes with topological charge m=1. This combination serves as a generator of electron vortex beams of high brilliance.

P. Schattschneider; M. Stger-Pollach; J. Verbeeck

2012-08-22T23:59:59.000Z

125

Rollover analysis of rotary mode core sampler truck No. 2  

SciTech Connect (OSTI)

This document provides estimate of limiting speed and rollover analysis of rotary mode core sampler truck No. 2 (RMCST No. 2).

Ziada, H.H.

1994-11-08T23:59:59.000Z

126

On the predictability of mode-1 internal tides  

Science Journals Connector (OSTI)

A frequencywavenumber tidal analysis for deriving internal-tide harmonic constants from TOPEX/Poseidon (T/P) measurements of sea-surface height (SSH) has been developed, taking advantage of the evident temporal and spatial coherence and the weak dissipation of internal tides. Previous analyses consisted of simple tidal analysis at individual points, which gave inconsistent harmonic constants at altimeter track crossover points. Such analyses have difficulty in distinguishing between the effects of interference, incoherence, and dissipation. The frequencywavenumber analysis provides an objective way to interpolate the internal tides measured along altimetry tracks to any arbitrary point, while leveraging all available data for optimal tidal estimates. Tidal analysis of T/P data from 2000 to 2007 is used to predict in situ time series measured during the 20012002 Hawaiian Ocean mixing experiment (HOME), the 1987 reciprocal tomography experiment (RTE87), and the 1991 acoustic mid-ocean dynamics experiment (AMODE), demonstrating both the temporal coherence and the lack of incoherent elements to this wave propagation. It has been conjectured that significant energy would be lost from mode-1 internal tides as they cross the 28.9N critical latitude of parametric subharmonic instability (PSI). No apparent change in amplitude at 28.9N was detected by this analysis, however. Further, after correcting for changes in background stratification, the amplitude of the mode-1 internal tide was found to decrease by less than 20% over the 2000km between the Hawaiian Ridge and 40N. A significant fraction of the variability of internal waves, that component associated with mode-1 internal tides, appears to be predictable over most of the world's oceans, using harmonic constants derived from satellite altimetry.

Brian D. Dushaw; Peter F. Worcester; Matthew A. Dzieciuch

2011-01-01T23:59:59.000Z

127

Discovery of a Neutron Star Oscillation Mode During a Superburst  

E-Print Network [OSTI]

Neutron stars are among the most compact objects in the universe and provide a unique laboratory for the study of cold ultra-dense matter. While asteroseismology can provide a powerful probe of the interiors of stars, for example, helioseismology has provided unprecedented insights about the interior of the sun, comparable capabilities for neutron star seismology have not yet been achieved. Here we report the discovery of a coherent X-ray modulation from the neutron star 4U 1636-536 during the February 22, 2001 thermonuclear superburst seen with NASA's Rossi X-ray Timing Explorer (RXTE) that is very likely produced by a global oscillation mode. The observed frequency is 835.6440 +- 0.0002 Hz (1.43546 times the stellar spin frequency of 582.14323 Hz) and the modulation is well described by a sinusoid ( A + Bsin(p - p0) ) with fractional half-amplitude of B/A = 0.19 +- 0.04% (4-15 keV). The observed frequency is consistent with the expected inertial frame frequency of a rotationally-modified surface g-mode, an ...

Strohmayer, Tod

2014-01-01T23:59:59.000Z

128

Parametric Excitation of Geodesic Acoustic Modes by Electron Drift Waves and Ion Temperature Gradient Modes in Tokamak Plasmas  

SciTech Connect (OSTI)

Geodesic Acoustic Modes (GAMs) have been predicted and subsequently observed in many toroidal plasma devices. Bicoherence studies on various devices have suggested three-wave mode coupling processes between GAMs and high frequency turbulence. Thus the parametric coupling of GAMS to drift waves and/or ion temperature gradient(ITG{r_brace} modes is a potential candidate for excitation of these modes. In this paper we discuss the resonant three-wave coupling mechanism for the excitation of GAMs by ITG and finite beta drift waves in homogeneous and inhomogeneous plasmas and compare theoretical predictions with observed characteristics of the GAMs.

Guzdar, P. N.; Kleva, R. G. [IREAP, University of Maryland, College Park, MD 20742 (United States); Chakrabarti, N. [SINP, Kolkata (India); Kaw, P. K.; Singh, R. [IPR, Gandhinagar, 308423 (India); Naulin, V.; Rasmussen, J. J. [EURATOM, Roskilde (Denmark)

2008-11-01T23:59:59.000Z

129

Quantum dynamics of two-optical modes and a single mechanical mode optomechanical system: selective energy exchange  

E-Print Network [OSTI]

We study the quantum dynamics of an optomechanical setup comprising two optical modes and one mechanical mode. We show that the same system can undergo a Dicke-Hepp-Lieb superradiant type phase transition. We found that the coupling between the momentum quadratures of the two optical fields give rise to a new critical point. We show that selective energy exchange between any two modes is possible by coherent control of the coupling parameters. In addition we also demonstrate the occurrence of Normal Mode Splitting (NMS) in the mechanical displacement spectrum.

Neha Aggarwal; Aranya B Bhattacherjee

2013-02-06T23:59:59.000Z

130

Three-dimensional Bernstein-Greene-Kruskal modes in a  

E-Print Network [OSTI]

Three-dimensional Bernstein- Greene-Kruskal modes in a multi-species plasma: Void solutions-dimensional (3D) Bernstein- Greene-Kruskal (BGK) mode [Ng and Bhattacharjee, Phys. Rev. Lett., 95, 245004 (2005 and the distribution function of the other species depending on energy and angular momentum. Some of these solutions

Ng, Chung-Sang

131

Kinetic theory of geodesic acoustic and related modes  

E-Print Network [OSTI]

be driven by high energy partricles? Transport regulation/modulation? Coupling to high energy particles-mode?" oscillations with · 1992: Chu, Green et al., Coupling of Alfven and sound continuum via geodesic curvature dispersion relation with 7/4, electromagnetic (Alfven modes) effects but no references to Winsor, Green

132

Localized radio frequency communication using asynchronous transfer mode protocol  

DOE Patents [OSTI]

A localized wireless communication system for communication between a plurality of circuit boards, and between electronic components on the circuit boards. Transceivers are located on each circuit board and electronic component. The transceivers communicate with one another over spread spectrum radio frequencies. An asynchronous transfer mode protocol controls communication flow with asynchronous transfer mode switches located on the circuit boards.

Witzke, Edward L. (Edgewood, NM); Robertson, Perry J. (Albuquerque, NM); Pierson, Lyndon G. (Albuquerque, NM)

2007-08-14T23:59:59.000Z

133

Mirror Mode Structures in the Solar Wind: STEREO Observations  

E-Print Network [OSTI]

Mirror Mode Structures in the Solar Wind: STEREO Observations O. Enríquez-Rivera1 , X. Blanco-Cano1 Autónoma de México, Coyoacán, D.F., 04510, MEXICO 2. Institute of Geophysics and Planetary Physics of California, Berkeley, CA 94720, USA Abstract. Mirror mode structures occur in the solar wind either

California at Berkeley, University of

134

FAILURE MODES AND EFFECTS ANALYSIS Dated: May 27, 2010  

E-Print Network [OSTI]

1 NSTX FAILURE MODES AND EFFECTS ANALYSIS (FMEA) Revision 7 Dated: May 27, 2010 Prepared By: Name.07.13 09:11:02 -04'00' #12;NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-7 / p. 2 of 120 2 Table

Princeton Plasma Physics Laboratory

135

Direct estimation of Patlak parameters from list mode pet data  

Science Journals Connector (OSTI)

We describe a method to directly estimate Patlak parameters from list mode data. Based on the Patlak model, the uptake rate function of each voxel can be written as a linear combination of the blood input function and its integral, with the slope and ... Keywords: FDG PET, PET, incremental gradient, list mode, the Patlak Model

Quanzheng Li; Richard M. Leahy

2009-06-01T23:59:59.000Z

136

Coherent Modes in the Acoustic Frequency Range in Tokamaks  

SciTech Connect (OSTI)

This paper presents a kinetic study of Geodesic Acoustic Modes and Beta Alfven Eigenmodes. The dispersion relations of both modes are similar, which make them difficult to discriminate. However their poloidal structures and excitation mechanisms are different, thus providing a way to characterize them unambiguously. These results are briefly discussed in relation with reflectometry measurements on Tore Supra.

Garbet, X.; Falchetto, G.; Ottaviani, M.; Sabot, R.; Sirinelli, A. [Association Euratom-CEA, CEA/DSM/DRFC CEA-Cadarache (France); Smolyakov, A. [Department of Physics and Engineering Physics, University of Saskatchewan, SK (Canada)

2006-11-30T23:59:59.000Z

137

Improved Wireless Performance from Mode Scattering in Ventilation Ducts  

E-Print Network [OSTI]

, the authors of [1] note a possible impact of mode scattering effects to the power levels measured in test HVAC filtering effect. So far this hypothesis has yet to be explorered. Al- though the authors of [2] present to investigate the impact that mode filtering has on an actual wireless communication. Experimental Analysis

Stancil, Daniel D.

138

Mode coherence at megameter ranges in the North Pacific Ocean  

E-Print Network [OSTI]

Mode coherence at megameter ranges in the North Pacific Ocean Kathleen E. Wage, Matthew A and the Acoustical Society of America. #12;Mode coherence at megameter ranges in the North Pacific Ocean Kathleen E Thermometry of Ocean Climate ATOC and Alternate Source Test AST experiments. Vertical line arrays at Hawaii

Wage, Kathleen

139

Numerical computation of the helical Chandrasekhar-Kendall modes  

Science Journals Connector (OSTI)

A new formulation is presented for numerically computing the helical Chandrasekhar-Kendall modes in an axisymmetric torus. It explicitly imposes @?.B=0 and yields a standard matrix eigenvalue problem, which can then be solved by standard matrix eigenvalue ... Keywords: Chandrasekhar-Kendall modes, Eigenvalue, Helicity injection, Magnetic relaxation, Reversed field pinch, Spherical tokamak, Taylor state

X. Z. Tang

2011-02-01T23:59:59.000Z

140

Instanton Fermionic Zero Modes of Heterotic CP(1) Sigma Model  

E-Print Network [OSTI]

We discuss instanton fermionic zero modes in the heterotic N=(0,2) modification of the CP(1) sigma model in two dimensions. By calculating its chiral anomaly we prove that the number of fermionic zero modes is same as in the standard N=(2,2) CP(1) case, and determine their explicit form.

Jin Chen

2009-12-03T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

Mixed-mode oscillations in chemical systems Valery Petrov  

E-Print Network [OSTI]

, leading to correspondingly more complete Devil's staircases. An ex- actly comparable scenario is shown. The relative extents of the mixed-mode and nonmixed- mode forms are summarized in terms of a Devil's staircase. The completeness of the staircase as a second parameter is varied is discussed. The mechanisms by which the system

Showalter, Kenneth

142

Number of negative modes of the oscillating bounces  

SciTech Connect (OSTI)

The spectrum of small perturbations about oscillating bounce solutions recently discussed in the literature is investigated. Our study supports quite intuitive and expected result: the bounce with N nodes has exactly N homogeneous negative modes. Existence of more than one negative modes makes obscure the relation of these oscillating bounce solutions to the false vacuum decay processes.

Lavrelashvili, George [Department of Theoretical Physics, University of Geneva, 24 quai Ernest-Ansermet, CH 1211 Geneva 4 (Switzerland) and Department of Theoretical Physics, A.Razmadze Mathematical Institute, GE 0193 Tbilisi (Georgia)

2006-04-15T23:59:59.000Z

143

Fast ion transport induced by saturated infernal mode  

SciTech Connect (OSTI)

Tokamak discharges with extended weak-shear central core are known to suffer from infernal modes when the core safety factor approaches the mode ratio. These modes can cause an outward convection of the well-passing energetic ions deposited in the core by fusion reactions and/or neutral beam injection. Convection mechanism consists in collisional slowing down of energetic ions trapped in the Doppler-precession resonance with a finite-amplitude infernal mode. Convection velocity can reach a few m/s in modern spherical tori. Possible relation of this transport with the enhanced fast ion losses in the presence of long lived modes in the MAST tokamak [I. T. Chapman et al., Nucl. Fusion 50, 045007 (2010)] is discussed.

Marchenko, V. S., E-mail: march@kinr.kiev.ua [Institute for Nuclear Research, Kyiv (Ukraine)

2014-05-15T23:59:59.000Z

144

Behavior of n = 1 magnetohydrodynamic modes of infernal type at high-mode pedestal with plasma rotation  

SciTech Connect (OSTI)

Magnetohydrodynamic instabilities of high-mode (H-mode) pedestal are investigated in this paper with the inclusion of bootstrap current for equilibrium and rotation for stability. The jointed European torus-like equilibria of H-mode discharges are generated numerically using the VMEC code. It is found that, when the bootstrap current is taken into account, a safety-factor reversal or plateau can be generated near plasma edge. This confirms previous results of numerical equilibrium reconstructions using other types of codes. The n = 1 magnetohydrodynamic instabilities, where n is toroidal mode number, are investigated numerically in this type of equilibria using the AEGIS code. It is found that the infernal type harmonic can prevail at safety-factor reversal or plateau region. The toroidal plasma rotation effect with low Mach number is investigated. The numerical results show that the mode frequency is close to the rotation frequency at pedestal top, when the value of safety factor at plateau is slightly above a rational number. This mode frequency range seems to coincide with the experimentally observed frequencies of n = 1 edge harmonic oscillations (or outer modes) at the quiescent H-mode discharges.

Zheng, L. J.; Kotschenreuther, M. T.; Valanju, P. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)

2013-01-15T23:59:59.000Z

145

Competition between modes with different axial structures in gyrotrons  

SciTech Connect (OSTI)

This study was motivated by some experiments in which it was found that during the voltage rise, instead of expected excitation of a high-frequency parasitic mode, the excitation of a lower-frequency parasitic mode takes place in a certain range of voltages. For explaining this fact, the dependence of start currents of possible competing modes on the beam voltage was carried out in the cold-cavity approximation and by using the self-consistent approach. It was found that in the case of cavities, which consist of the combination of a section of constant radius waveguide and a slightly uptapered waveguide, these two approaches yield completely different results. Thus, experimentally observed excitation of the low-frequency parasitic mode can be explained by the self-consistent modification of the axial profile of the excited field, which has strong influence on the diffractive quality factor of competing modes. This modification is especially pronounced in the case of excitation of modes with many axial variations which can be excited in the region of beam interaction with the backward-wave component of such modes.

Khutoryan, Eduard M. [O. Ya. Usikov Institute for Radiophysics and Electronics, 12, Proskura str., Kharkiv 61085 (Ukraine); Nusinovich, Gregory S.; Sinitsyn, Oleksandr V. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742-3511 (United States)

2014-09-15T23:59:59.000Z

146

Mode coupling in quantized high-quality films  

Science Journals Connector (OSTI)

The effect of coupling of quantized modes on transport and localization in ultrathin films with quantum size effect (QSE) is discussed. The emphasis is on comparison of films with Gaussian, exponential, and power-law long-range behavior of the correlation function of surface, thickness, or bulk fluctuations. For small-size inhomogeneities, the mode coupling is the same for inhomogeneities of all types and the transport coefficients behave in the same way. The mode coupling becomes extremely sensitive to the correlators for large-size inhomogeneities leading to the drastically distinct behavior of the transport coefficients. In high-quality films there is a noticeable difference between the QSE patterns for films with bulk and surface inhomogeneities, which explains why the recently predicted type of QSE with large oscillations of the transport coefficients can be observed mostly in films with surface-driven relaxation. In such films with surface-dominated scattering the higher modes contribute to the transport only as a result of opening of the corresponding mode coupling channels and appear one by one. Mode coupling also explains a much higher transport contribution from the higher modes than it is commonly believed. Possible correlations between the inhomogeneities from the opposite walls provide, because of their oscillating response to the mode quantum numbers, a unique insight into the mode coupling. The presence of inhomogeneities of several sizes leads not to a mechanical mixture of QSE patterns, but to the overall shifting and smoothing of the oscillations. The results can lead to unique non-destructive ways of analysis of the buried interfaces and to study of inhomogeneities on the scales which are inaccessible for scanning techniques.

Yiying Cheng and A. E. Meyerovich

2006-02-06T23:59:59.000Z

147

Distilling quantum entanglement via mode-matched filtering  

SciTech Connect (OSTI)

We propose an avenue toward distillation of quantum entanglement that is implemented by directly passing the entangled qubits through a mode-matched filter. This approach can be applied to a common class of entanglement impurities appearing in photonic systems, where the impurities inherently occupy different spatiotemporal modes than the entangled qubits. As a specific application, we show that our method can be used to significantly purify the telecom-band entanglement generated via the Kerr nonlinearity in single-mode fibers where a substantial amount of Raman-scattering noise is concomitantly produced.

Huang Yuping; Kumar, Prem [Center for Photonic Communication and Computing, EECS Department, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3118 (United States)

2011-09-15T23:59:59.000Z

148

N-mode coherence in collective neutrino oscillations  

SciTech Connect (OSTI)

We study two-flavor neutrino oscillations in a homogeneous and isotropic ensemble under the influence of neutrino-neutrino interactions. For any density there exist forms of collective oscillations that show self-maintained coherence. They can be classified by a number N of linearly independent functions that describe all neutrino modes as linear superpositions. What is more, the dynamics is equivalent to another ensemble with the same effective density, consisting of N modes with discrete energies E{sub i} with i=1,...,N. We use this equivalence to derive the analytic solution for two-mode (bimodal) coherence, relevant for spectral-split formation in supernova neutrinos.

Raffelt, Georg G. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany)

2011-05-15T23:59:59.000Z

149

Separating and combining single-mode and multimode optical beams  

DOE Patents [OSTI]

Techniques for combining initially separate single mode and multimode optical beams into a single "Dual Mode" fiber optic have been developed. Bi-directional propagation of two beams that are differentiated only by their mode profiles (i.e., wavefront conditions) is provided. The beams can be different wavelengths and or contain different modulation information but still share a common aperture. This method allows the use of conventional micro optics and hybrid photonic packaging techniques to produce small rugged packages suitable for use in industrial or military environments.

Ruggiero, Anthony J; Masquelier, Donald A; Cooke, Jeffery B; Kallman, Jeffery S

2013-11-12T23:59:59.000Z

150

Zero sound modes of dilute Fermi gases with arbitrary spin  

Science Journals Connector (OSTI)

Motivated by the recent success of optical trapping of alkali-metal bosons, we have studied the zero sound modes of dilute Fermi gases with arbitrary spin-f, which are spin-S excitations (0<~S<~2f). The dispersion of the mode (S) depends on a single Landau parameter F(S), which is related to the scattering lengths of the system through a simple formula. Measurement of (even a subset of) these modes in finite magnetic fields will enable one to determine all the interaction parameters of the system.

S.-K. Yip and Tin-Lun Ho

1999-06-01T23:59:59.000Z

151

Temporal Coherence of Normal Modes in an Ocean Waveguide  

Science Journals Connector (OSTI)

The coherence time of acoustic signals is derived using coupled mode equation to the first order of sound speed perturbation squared. It is found that mode coupling induced by internal waves in a waveguide changes the temporal coherence of the acoustic field. For a typical shallow water environment numerical results show that the coherence time of acoustic field decreases as ?3/2 power of frequency and ?1/2 power of range at high frequencies in accord with experimental data. Ignoring the mode coupling the coherence time of acoustic field decreases as ?1 power of frequency and ?1/2 power of range same as that predicted for acoustic rays.

T. C. Yang

2010-01-01T23:59:59.000Z

152

Energetic-Particle-Induced Geodesic Acoustic Mode Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA  

E-Print Network [OSTI]

Energetic-Particle-Induced Geodesic Acoustic Mode G. Y. Fu* Princeton Plasma Physics Laboratory-induced geodesic acoustic mode (EGAM) is shown to exist. The mode frequency and mode structure are determined comparable to that of geodesic acoustic mode (GAM) [4]. Here it is shown analytically and numerically

153

Comparison of Two Self-Synchronizing Cipher Modes Fang Yang and Howard M. Heys  

E-Print Network [OSTI]

the basic cipher feedback (CFB) mode, but, although both modes are suitable for high speed digital hardware] and optimized cipher feedback (OCFB) mode [2]. II. BACKGROUND Cipher feedback (CFB) mode and output feedback length and m to represent the feedback size. CFB mode, as shown in Figure 1, encrypts m bits of plaintext

Heys, Howard

154

Hardware Design and Analysis of Statistical Cipher Feedback Mode Using Serial Transfer  

E-Print Network [OSTI]

to the Ciphertext Queue. SCFB mode is the hybrid of output feedback (OFB) mode and cipher feedback (CFB) mode feeds back ciphertext to the input of the block cipher similar to the conventional CFB mode, except- plementation than conventional CFB mode. An iterative based implementation of the Advanced Encryption Strandard

Heys, Howard

155

Selection of modes in transverse-mode waveguides for semiconductor lasers based on asymmetric heterostructures  

SciTech Connect (OSTI)

Asymmetric Al{sub 0.3}Ga{sub 0.7}As/GaAs/InGaAs heterostructures with a broadened waveguide produced by the method of MOCVD epitaxy are studied. It is established that the precision shift of the active region to one of the cladding layers ensures the generation of the chosen mode of high order in the transverse broadened waveguide. It is experimentally established that this shift brings about an increase in internal optical losses and a decrease in the internal quantum efficiency of stimulated emission. It is shown experimentally that the shift of the active region to the n-type cladding layer governs the sublinear form of the power-current characteristic for semiconductor lasers; in the case of a shift of the active region towards the p-type cladding layer, the laser diodes demonstrated a linear dependence of optical power on the pump current in the entire range of pump currents.

Slipchenko, S. O., E-mail: Serghpl@mail.ioffe.ru; Bondarev, A. D.; Vinokurov, D. A.; Nikolaev, D. N.; Fetisova, N. V.; Sokolova, Z. N.; Pikhtin, N. A.; Tarasov, I. S. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

2009-01-15T23:59:59.000Z

156

Detecting individual gravity modes in the Sun: Chimera or reality?  

E-Print Network [OSTI]

Over the past 15 years, our knowledge of the interior of the Sun has tremendously progressed by the use of helioseismic measurements. However, to go further in our understanding of the solar core, we need to measure gravity (g) modes. Thanks to the high quality of the Doppler-velocity signal measured by GOLF/SoHO, it has been possible to unveil the signature of the asymptotic properties of the solar g modes, thus obtaining a hint of the rotation rate in the core. However, the quest for the detection of individual g modes is not yet over. In this work, we apply the latest theoretical developments to guide our research using GOLF velocity time series. In contrary to what was thought till now, we are maybe starting to identify individual low-frequency g modes...

Garcia, Rafael A; Eff-Darwich, A; Garrido, R; Jimenez, A; Mathis, S; Mathur, S; Moya, A; Palle, P L; Regulo, C; Salabert, D; Sato, K; Suarez, J C; Turck-Chieze, S

2009-01-01T23:59:59.000Z

157

Stabilit magntohydrodynamique des modes ballooning dans un Tokamak  

Science Journals Connector (OSTI)

We implanted in the ERATO spectral code [1] the stability criterion for ballooning modes (toroidal wave numbern??) [2]. The study of ballooning waves located around a given magnetic surface reduces itself to the ...

S. Rousset; R. Gruber; F. Troyon

158

Two Modes of Change of the Distribution of Rain  

Science Journals Connector (OSTI)

The frequency and intensity of rainfall determine its character and may change with climate. A methodology for characterizing the frequency and amount of rainfall as functions of the rain rate is developed. Two modes of response are defined, one ...

Angeline G. Pendergrass; Dennis L. Hartmann

2014-11-01T23:59:59.000Z

159

Synthesis of the vector resonator modes from scalar results  

Science Journals Connector (OSTI)

A technique is presented in which the full vector solution for resonator modes is synthesized from the known scalar solution. Second-order perturbation theory is utilized to predict...

Tyler, G A; Southwell, W H

1980-01-01T23:59:59.000Z

160

Study of the Glauber correlation functions in a pulsed mode  

Science Journals Connector (OSTI)

A method for measuring the Glauber correlation functions in a pulsed mode is proposed. The effect of the detector dead time on the shape of a measured correlation function is analyzed. The second-order intensi...

I. N. Agafonov; T. Sh. Iskhakov; M. V. Chekhova

2007-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

Graphene mode-locked femtosecond laser at 2?m wavelength  

Science Journals Connector (OSTI)

We experimentally demonstrated a passively mode-locked femtosecond laser by using a graphene-based saturable absorber mirror (graphene SAM) in the spectral region of 2?m. The graphene...

Ma, J; Xie, G Q; Lv, P; Gao, W L; Yuan, P; Qian, L J; Yu, H H; Zhang, H J; Wang, J Y; Tang, D Y

2012-01-01T23:59:59.000Z

162

Sliding-mode amplitude control techniques for harmonic oscillators  

E-Print Network [OSTI]

This thesis investigates both theoretical and implementation-level aspects of switching- feedback control strategies for the development of voltage-controlled oscillators. We use a modified sliding-mode compensation scheme based on various norms...

Marquart, Chad A.

2007-09-17T23:59:59.000Z

163

Investigation of dominant spin wave modes by domain walls collision  

SciTech Connect (OSTI)

Spin wave emission due to field-driven domain wall (DW) collision has been investigated numerically and analytically in permalloy nanowires. The spin wave modes generated are diagonally symmetric with respect to the collision point. The non-propagating mode has the highest amplitude along the middle of the width. The frequency of this mode is strongly correlated to the nanowire geometrical dimensions and is independent of the strength of applied field within the range of 0.1?mT to 1?mT. For nanowire with film thickness below 5?nm, a second spin wave harmonic mode is observed. The decay coefficient of the spin wave power suggests that the DWs in a memory device should be at least 300?nm apart for them to be free of interference from the spin waves.

Ramu, M.; Purnama, I.; Goolaup, S.; Chandra Sekhar, M.; Lew, W. S., E-mail: wensiang@ntu.edu.sg [School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

2014-06-28T23:59:59.000Z

164

A way to use an induction generator in economy mode  

Science Journals Connector (OSTI)

A way to connect low-power induction generators with other independent ac sources or with ... We theoretically ground and experimentally confirm that such generators can operate under an economy mode.

P. A. Kuntsevich; G. A. Prokhorova; V. A. Gusarova

2012-04-01T23:59:59.000Z

165

Data sheet acquired from Harris Semiconductor Four Operating Modes  

E-Print Network [OSTI]

1 Data sheet acquired from Harris Semiconductor SCHS164F Features · Four Operating Modes - Shift Ld PDIP NOTE: When ordering, use the entire part number. The suffixes 96 and R denote tape and reel

Kretchmar, R. Matthew

166

Synthesis of electromagnetic modes in photonic band gap fibers  

E-Print Network [OSTI]

In this paper, we report on the successful synthesis of three individual modes, HE11, TEo0, and TE02 for transmission in photonic band gap fibers at near infrared wavelengths. We measure the propagation losses of the HE11 ...

Hu, Qichao

2007-01-01T23:59:59.000Z

167

On the origin of the outgoing black hole modes  

Science Journals Connector (OSTI)

The question of how to account for the outgoing black hole modes without drawing upon a trans-Planckian reservoir at the horizon is addressed. It is argued that the outgoing modes must arise via conversion from ingoing modes. It is further argued that the back reaction must be included to avoid the conclusion that particle creation cannot occur in a strictly stationary background. The process of mode conversion is known in plasma physics by this name and in condensed matter physics as Andreev reflection or branch conversion. It is illustrated here in a linear Lorentz noninvariant model introduced by Unruh. The role of interactions and a physical short distance cutoff is then examined in the sonic black hole formed with helium-II. 1996 The American Physical Society.

Ted Jacobson

1996-06-15T23:59:59.000Z

168

Failure mode and effects analysis outputs: are they valid?  

Science Journals Connector (OSTI)

Failure Mode and Effects Analysis (FMEA) is a prospective risk assessment tool that ... this study was to explore the validity of FMEA outputs within a hospital setting in the...

Nada Atef Shebl; Bryony Dean Franklin; Nick Barber

2012-06-01T23:59:59.000Z

169

Facilitation of neuronal responses by intrinsic default mode network activity  

Science Journals Connector (OSTI)

Default mode network (DMN) shows intrinsic, high-level activity at rest. We tested a hypothesis proposed for its role in sensory information processing: Intrinsic DMN activity facilitates neural responses to sensory input. A neural network model, consisting ...

Hiroakira Matsui, Meihong Zheng, Osamu Hoshino

2014-11-01T23:59:59.000Z

170

Acoustic modes in metallic nanoparticles: Atomistic versus elasticity modeling  

Science Journals Connector (OSTI)

The validity of the linear elasticity theory is examined at the nanometer scale by investigating the vibrational properties of silver and gold nanoparticles whose diameters range from about 1.54 nm. Comparing the vibration modes calculated by elasticity theory and atomistic simulation based on the embedded-atom method, we first show that the anisotropy of the stiffness tensor in elastic calculation is essential to ensure a good agreement between elastic and atomistic models. Second, we illustrate the reduction in the number of vibration modes due to the diminution of the number of atoms when reducing the nanoparticles size. Finally, we exhibit a breakdown of the frequency-spectra scaling of the vibration modes and attribute it to surface effects. Some critical sizes under which such effects are expected, depending on the material and the considered vibration modes, are given.

Nicolas Combe and Lucien Saviot

2009-07-10T23:59:59.000Z

171

Gearbox Typical Failure Modes, Detection, and Mitigation Methods (Presentation)  

SciTech Connect (OSTI)

This presentation was given at the AWEA Operations & Maintenance and Safety Seminar and focused on what the typical gearbox failure modes are, how to detect them using detection techniques, and strategies that help mitigate these failures.

Sheng, S.

2014-01-01T23:59:59.000Z

172

Front propagation and mode-locking in Coupled Map Lattices  

E-Print Network [OSTI]

of the travelling interface has a Devil's staircase (a fractal staircase) dependence on the coupling parameter. The Devil's staircase is mode-locked to rational plateaus and may be fully described via Farey sequences

Carretero, Ricardo

173

Overview of H-mode studies in DIII-D  

Science Journals Connector (OSTI)

A major portion of the DIII-D program includes studies of the L-H transition, of the VH-mode, of particle transport and control and of the power-handling capability of a divertor. Significant progress has been made in all of these areas and the aim is to summarize the major results. An increased understanding of the origin of improved confinement in H-mode and in VH-mode discharges has been obtained, good impurity control has been achieved in several operating scenarios, studies of helium transport provide encouraging results from the point of view of reactor design, an actively pumped divertor chamber has controlled the density in H-mode discharges and a radiative divertor is a promising technique for controlling the heat flux from the main plasma.

R J Groebner; S L Allen; D R Baker; N H Brooks; D A Buchenauer; K H Burrell; T N Carlstrom; M S Chu; S Coda; J Cuthbertson; E J Doyle; T E Evans; J R Ferron; D Finkenthal; A H Futch; P Gohil; C M Greenfield; D N Hill; D L Hillis; F L Hinton; J Hogan; C L Hsieh; A W Hyatt; G L Jackson; R Jong; J Kim; Y B Kim; C C Klepper; S Konoshima; R J La Haye; L L Lao; C J Lasnier; E A Lazarus; A W Leonard; S I Lippmann; M A Mahdavi; R Maingi; W Mandl; Y Martin; R A Moyer; T H Osborne; W A Peebles; T W Petrie; G D Porter; M E Rensink; C L Rettig; T H Rhodes; M J Schaffer; D P Schissel; R P Seraydarian; R T Snider; G M Staebler; R D Stambaugh; H St John; E J Strait; T S Taylor; D M Thomas; S J Thompson; A D Turnbull; M R Wade; J G Watkins; W P West; R D Wood; D Wroblewski

1994-01-01T23:59:59.000Z

174

Gyrokinetic treatment of GAE modes in cylindrical geometry  

SciTech Connect (OSTI)

Global Alfven eigenmodes (GAEs) are investigated in cylindrical geometry both analytically and numerically. These modes are of particular importance in low-shear magnetic configurations, such as modern stellarators. Analytical treatment starts from the linearised equations of gyrokinetics and yields a generalized dispersion relation for GAE with FLR and kinetic effects taken into account, which is demonstrated to reduce to the well-known MHD counterpart in the appropriate limit. An eigenvalue code is developed to solve the dispersion relation, which is used to investigate the kinetic analogs of GAE modes in various regimes with different beta. On the other hand, GAE modes are simulated with global linear particle-in-cell (PIC) electromagnetic gyrokinetic code following self-consistent time evolution of electromagnetic fields and plasma. GAE modes are observed and their damping rate agrees with predictions made by the eigenvalue code.

Eremin, D. [Max-Plank-Institut fuer Plasmaphysik, EUROATOM-Association, D-17491 Greifswald (Germany)

2006-11-30T23:59:59.000Z

175

Shock induced multi-mode damage in depleted uranium  

SciTech Connect (OSTI)

Recent dynamic damage studies on depleted uranium samples have revealed mixed mode failure mechanisms leading to incipient cracking as well as ductile failure processes. Results show that delamination of inclusions upon compression may provide nucleation sites for damage initiation in the form of crack tip production. However, under tension the material propagates cracks in a mixed shear localization and mode-I ductile tearing and cracking. Cracks tips appear to link up through regions of severe, shear dominated plastic flow. Shock recovery experiments were conducted on a 50 mm single stage light gas gun. Serial metallographic sectioning was conducted on the recovered samples to characterize the bulk response of the sample. Experiments show delaminated inclusions due to uniaxial compression without damage propagation. Further results show the propagation of the damage through tensile loading to the incipient state, illustrating ductile processes coupled with mixed mode-I tensile ductile tearing, shear localization, and mode-I cracking in depleted uranium.

Koller, Darcie D [Los Alamos National Laboratory; Cerreta, Ellen K [Los Alamos National Laboratory; Gray, Ill, George T [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

176

Zero sound modes in the AdS/CFT correspondence  

E-Print Network [OSTI]

We examine the effects of zero sound wave excitations of charged fermion species living around the charged black hole of an AdS/CFT spacetime. In particular, we show that these bulk modes cause corresponding singularities ...

Roxlo, Thomas (Thomas Q.)

2012-01-01T23:59:59.000Z

177

Coherence area profiling in multi-spatial-mode squeezed states  

E-Print Network [OSTI]

The presence of multiple bipartite entangled modes in squeezed states generated by four wave mixing in atomic vapors enables ultra-trace sensing, imaging, and metrology applications that are impossible to achieve with single-spatial-mode squeezed states. For Gaussian seed beams, the spatial distribution of bipartite entangled modes, or coherence areas, across each beam is largely dependent on the spatial modes present in the pump beam, but it has proven difficult to map the distribution of these coherence areas in frequency and space. We demonstrate an accessible method to map the distribution of the coherence areas within these twin beams. We also show that the pump shape can impart different noise properties to each coherence area, and that it is possible to select and detect coherence areas with optimal squeezing with this approach.

Lawrie, B J; Otterstrom, N

2014-01-01T23:59:59.000Z

178

Gravito-inertial modes in a differentially rotating spherical shell  

E-Print Network [OSTI]

While many intermediate- and high-mass main sequence stars are rapidly and differentially rotating, the effects of rotation on oscillation modes are poorly known. In this communication we present a first study of axisymmetric gravito-inertial modes in the radiative zone of a differentially rotating star. We consider a simplified model where the radiative zone of the star is a linearly stratified rotating fluid within a spherical shell, with differential rotation due to baroclinic effects. We solve the eigenvalue problem with high-resolution spectral computations and determine the propagation domain of the waves through the theory of characteristics. We explore the propagation properties of two kinds of modes: those that can propagate in the entire shell and those that are restricted to a subdomain. Some of the modes that we find concentrate kinetic energy around short-period shear layers known as attractors. We describe various geometries for the propagation domains, conditioning the surface visibility of the...

Mirouh, Giovanni M; Rieutord, Michel; Ballot, Jrme

2014-01-01T23:59:59.000Z

179

Pseudo-Goldstone modes in isospin-asymmetric nuclear matter  

SciTech Connect (OSTI)

The authors analyze the chiral limit in dense isospin-asymmetric nuclear matter. It is shown that the pseudo-Goldstone modes in this system are qualitatively different from the case of isospin-symmetric matter.

Cohen, T.D. [Univ. of Washington, Seattle, WA (United States); Broniowski, W. [H. Niewodniczanski Institute of Nuclear Physics, Cracow (Poland)

1995-01-01T23:59:59.000Z

180

Charging system with galvanic isolation and multiple operating modes  

DOE Patents [OSTI]

Systems and methods are provided for operating a charging system with galvanic isolation adapted for multiple operating modes. A vehicle charging system comprises a DC interface, an AC interface, a first conversion module coupled to the DC interface, and a second conversion module coupled to the AC interface. An isolation module is coupled between the first conversion module and the second conversion module. The isolation module comprises a transformer and a switching element coupled between the transformer and the second conversion module. The transformer and the switching element are cooperatively configured for a plurality of operating modes, wherein each operating mode of the plurality of operating modes corresponds to a respective turns ratio of the transformer.

Kajouke, Lateef A.; Perisic, Milun; Ransom, Ray M.

2013-01-08T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

A mechanical mode-stirred reverberation chamber with chaotic geometry  

E-Print Network [OSTI]

A previous research on multivariate approach to the calculation of reverberation chamber correlation matrices is used to calculate the number of independent positions in a mode-stirred reverberation chamber. Anomalies and counterintuitive behavior are observed in terms of number of correlated matrix elements with respect to increasing frequency. This is ascribed to the regular geometry forming the baseline cavity (screened room) of a reverberation chamber, responsible for localizing energy and preserving regular modes (bouncing ball modes). Smooth wall deformations are introduced in order to create underlying Lyapunov instability of rays and then destroy survived regular modes. Numerical full-wave simulations are performed for a reverberation chamber with corner hemispheres and (off-)center wall spherical caps. Field sampling is performed by moving a mechanical carousel stirrer. It is found that wave-chaos inspired baseline geometries improve chamber performances in terms of lowest usable frequencies and number of independent cavity realizations of mechanical stirrers.

Gabriele Gradoni; Franco Moglie; Valter Mariani Primiani

2014-07-06T23:59:59.000Z

182

Specifying mode requirements of embedded systems Graeme Smith  

E-Print Network [OSTI]

Specifying mode requirements of embedded systems Graeme Smith Software Verification Research Centre University of Queensland, Australia Email: smith@svrc.uq.edu.au Abstract This paper presents a formal

Smith, Graeme

183

Phosphate Minerals: Their Properties and General Modes of Occurrence  

Science Journals Connector (OSTI)

This chapter presents a review of the physical, chemical and crystallographic properties of phosphate minerals, and discusses their general modes of occurrence. It provides the necessary backdrop to the subseq...

Jerome O. Nriagu

1984-01-01T23:59:59.000Z

184

Mode conversation losses in overmolded millimeter wave transmission lines  

E-Print Network [OSTI]

Millimeter wave transmission lines are integral components for many important applications like nuclear fusion and NMR spectroscopy. In low loss corrugated transmission lines propagating the HE,1 mode with a high waveguide ...

Tax, David S. (David Samuel)

2008-01-01T23:59:59.000Z

185

MODE II FRACTURE BEHAVIOR OF BONDED VISCOELASTIC THERMAL COMPRESSED WOOD  

E-Print Network [OSTI]

MODE II FRACTURE BEHAVIOR OF BONDED VISCOELASTIC THERMAL COMPRESSED WOOD Andreja Kutnar* Graduate Student Department of Wood Science and Technology Biotechnical Faculty University of Ljubljana 1000 Ljubljana, Slovenia Frederick A. Kamke Professor John A. Nairn Professor Department of Wood Science

Nairn, John A.

186

Spectrally tailored supercontinuum generation from single-mode-fiber amplifiers  

SciTech Connect (OSTI)

Spectral filtering of an all-normal-dispersion Yb-doped fiber laser was demonstrated effective for broadband supercontinuum generation in the picosecond time region. The picosecond pump pulses were tailored in spectrum with 1 nm band-pass filter installed between two single-mode fiber amplifiers. By tuning the spectral filter around 1028?nm, four-wave mixing was initiated in a photonic crystal fiber spliced with single-mode fiber, as manifested by the simultaneous generation of Stokes wave at 1076?nm and anti-Stokes wave at 984?nm. Four-wave mixing took place in cascade with the influence of stimulated Raman scattering and eventually extended the output spectrum more than 900?nm of 10?dB bandwidth. This technique allows smooth octave supercontinuum generation by using simple single-mode fiber amplifiers rather than complicated multistage large-mode-area fiber amplifiers.

Hao, Qiang; Guo, Zhengru; Zhang, Qingshan [Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System (Ministry of Education), School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai 200093 (China); Liu, Yang; Li, Wenxue [State Key Laboratory of Precision Spectroscopy, East China Normal University, 3663 Zhongshan North Road, Shanghai 200062 (China); Zeng, Heping, E-mail: hpzeng@phy.ecnu.edu.cn [Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System (Ministry of Education), School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai 200093 (China); State Key Laboratory of Precision Spectroscopy, East China Normal University, 3663 Zhongshan North Road, Shanghai 200062 (China)

2014-05-19T23:59:59.000Z

187

Design for a single mode erbium-doped fiber laser  

E-Print Network [OSTI]

Delayed Self-Homodyne Technique Measurement of Linewidth Using the Longitudinal-modes Heterodyne Beat Signal VI FUTURE WORK Mirror Reflectivity Temperature Stabilization Splice Loss VII CONCLUSIONS 9 16 20 20 21 23 24 27 27 28 28 31... Delayed self-homodyne linewidth measurement, 22 23 LIST OF FIGURES (Continued) FIGURE Page 17 Beat signal between two adjacent longitudinal modes. 24 18 Beat signal of frequency heterodyning. 26 19 Normalized laser output as a function of output...

Wang, Jon-En

2012-06-07T23:59:59.000Z

188

Keyboard design variables in dual task mode selection  

E-Print Network [OSTI]

USAF flight gloves. The experimental tasks were as follows: (a) pilots centering a set of crosshairs on a CRT using a joystick with the right hand and; (b) pilots simultaneously performing (a) and selecting flight modes with the left hand without... observing the keyboard. The study investigated the effect of keyboard size, angle of inclination of the keyboard and with and without gloves on response time, keying errors and tracking scores. The flight mode locations remained constant throughout...

Hansen, Mark Douglas

2012-06-07T23:59:59.000Z

189

Determination of a flow generating a neutral magnetic mode  

E-Print Network [OSTI]

The problem of reconstruction of a flow of conducting incompressible fluid generating a given magnetic mode is considered. We use the magnetic induction equation to derive ordinary differential equations along the magnetic field lines, which give an opportunity to determine the generating flow, if additional data is provided on a two-dimensional manifold transversal to magnetic field lines, and show that an arbitrary solenoidal vector field can not be a neutral magnetic mode sustained by any flow of conducting fluid.

V. Zheligovsky

2009-06-30T23:59:59.000Z

190

Texas' cotton distribution patterns and utilized transportation modes  

E-Print Network [OSTI]

, the impor- tance of which have . increased whereas Texas ports' importance decreased ' substantially. Study findings indicate that the truck mode was used to move the ' majority of Texas cotton, increasing its market share at the expense of the rail... favorable impression of the truck mode whereas rail carriers major weaknesses are acknowledged. iv It was found that the market area of warehouses collecting univer- sal density bales is larger than that of warehouses collecting modified flat bales...

Vulcain, Ronald JMA

1984-01-01T23:59:59.000Z

191

Multi mode nano scale Raman echo quantum memory  

E-Print Network [OSTI]

Low loss magnetic surface plasmon polariton (SPP) modes characterized by enhanced electrical field component and subwavelength confinement on the dielectric and negative-index metamaterial interface are presented. We demonstrate a possibility of storage and perfect retrieval of the low loss magnetic SPP fields by using a photon echo quantum memory on Raman atomic transition. We describe specific properties of the proposed technique which opens a possibility for efficient nano scale multi-mode quantum memory.

S. A. Moiseev; E. S. Moiseev

2010-01-31T23:59:59.000Z

192

Electromagnetic modes in metal-insulator-metal structures  

Science Journals Connector (OSTI)

Metal-dielectric-metal structures are constructed by depositing Ag films on CaF2 thin films that coat Ag surfaces. The reflectance of such structures was measured for several angles of incidence in the 15-eV spectral range. The minima observed in the reflectance are due to the excitation of electromagnetic modes inside an optical cavity. These observed electromagnetic modes are discussed and compared to computed dispersion.

F. Villa; T. Lopez-Rios; L. E. Regalado

2001-04-02T23:59:59.000Z

193

Mode dependent lattice thermal conductivity of single layer graphene  

SciTech Connect (OSTI)

Molecular dynamics simulation is performed to extract the phonon dispersion and phonon lifetime of single layer graphene. The mode dependent thermal conductivity is calculated from the phonon kinetic theory. The predicted thermal conductivity at room temperature exhibits important quantum effects due to the high Debye temperature of graphene. But the quantum effects are reduced significantly when the simulated temperature is as high as 1000?K. Our calculations show that out-of-plane modes contribute about 41.1% to the total thermal conductivity at room temperature. The relative contribution of out-of-plane modes has a little decrease with the increase of temperature. Contact with substrate can reduce both the total thermal conductivity of graphene and the relative contribution of out-of-plane modes, in agreement with previous experiments and theories. Increasing the coupling strength between graphene and substrate can further reduce the relative contribution of out-of-plane modes. The present investigations also show that the relative contribution of different mode phonons is not sensitive to the grain size of graphene. The obtained phonon relaxation time provides useful insight for understanding the phonon mean free path and the size effects in graphene.

Wei, Zhiyong; Yang, Juekuan; Bi, Kedong; Chen, Yunfei, E-mail: yunfeichen@seu.edu.cn [Jiangsu Key Laboratory for Design and Manufacture of Micro/Nano Biomedical Instruments and School of Mechanical Engineering, Southeast University, Nanjing 210096 (China)

2014-10-21T23:59:59.000Z

194

High-Energy Four-Wave Mixing, with Large-Mode-Area Higher-Order Modes in Optical Fibres  

Science Journals Connector (OSTI)

Abstract (40-Word Limit): We demonstrate, for the first time, four-wave mixing, in the 1-?m spectral regime, in an LMA silica fiber. Pumping a 618-?m2 LP07 mode (?o =...

Rishj, Lars S; Steinvurzel, Paul E; Chen, Yuhao; Yan, Lu; Demas, Jeffrey; Grogan, Michael; Ellenbogen, Tal; Crozier, Ken; Rottwitt, Karsten; Ramachandran, Siddharth

195

E-Print Network 3.0 - amplitude inversion mode Sample Search...  

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

of island amplitude HF modes appear if the low-frequency oscillation... in FIG. 4. HF modes frequency increases by 30% while island ... Source: Vlad, Gregorio - Associazione...

196

TE Link Dormant Mode Used in GMPLS Optical Transport Networks for Energy Saving  

Science Journals Connector (OSTI)

This paper evaluates power efficiency of TE link dormant mode in optical transport network, considering daily traffic variability and GMPLS protocol. The proposed TE link dormant mode...

Li, Xin; Huang, Shanguo; Guo, Bingli; Zhang, Jie; Gu, Wanyi

197

Extended Substitution Cipher Chaining mode (ESCC) Mohamed Abo El-Fotouh and Klaus Diepold  

E-Print Network [OSTI]

vectors like in CBC, CFB and OFB modes [16], coun- ters like in CTR [15] or nonces like in OCB mode [18

198

Integration of Failure Modes and Effects Analysis (FMEA) in the Engineering Design Process.  

E-Print Network [OSTI]

??ABSTRACT Integration of Failure Modes and Effects Analysis (FMEA) in the Engineering Design Process Hua-wei Wen Failure modes and effects analysis (FMEA) is one of (more)

Wen, Hua-wei

2013-01-01T23:59:59.000Z

199

E-Print Network 3.0 - automotive switch-mode audio Sample Search...  

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

advantages and problems when implementing direct energy conversion switching-mode audio power... on a direct-conversion switching-mode audio power ampli- ... Source: Ris National...

200

E-Print Network 3.0 - a-mode ultrasound devices Sample Search...  

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

Mode (A-mode) Ultrasound Imaging... Laboratory www.apl.washington.eduaboutabout.php 2008 Mike Bailey Method and Device to Use Ultrasound... to Evaluate Prosthetic Sockets...

Note: This page contains sample records for the topic "modes mode fraction" 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

ACCURATE CHARACTERIZATION OF HIGH-DEGREE MODES USING MDI OBSERVATIONS  

SciTech Connect (OSTI)

We present the first accurate characterization of high-degree modes, derived using the best Michelson Doppler Imager (MDI) full-disk full-resolution data set available. A 90 day long time series of full-disk 2 arcsec pixel{sup -1} resolution Dopplergrams was acquired in 2001, thanks to the high rate telemetry provided by the Deep Space Network. These Dopplergrams were spatially decomposed using our best estimate of the image scale and the known components of MDI's image distortion. A multi-taper power spectrum estimator was used to generate power spectra for all degrees and all azimuthal orders, up to l = 1000. We used a large number of tapers to reduce the realization noise, since at high degrees the individual modes blend into ridges and thus there is no reason to preserve a high spectral resolution. These power spectra were fitted for all degrees and all azimuthal orders, between l = 100 and l = 1000, and for all the orders with substantial amplitude. This fitting generated in excess of 5.2 Multiplication-Sign 10{sup 6} individual estimates of ridge frequencies, line widths, amplitudes, and asymmetries (singlets), corresponding to some 5700 multiplets (l, n). Fitting at high degrees generates ridge characteristics, characteristics that do not correspond to the underlying mode characteristics. We used a sophisticated forward modeling to recover the best possible estimate of the underlying mode characteristics (mode frequencies, as well as line widths, amplitudes, and asymmetries). We describe in detail this modeling and its validation. The modeling has been extensively reviewed and refined, by including an iterative process to improve its input parameters to better match the observations. Also, the contribution of the leakage matrix on the accuracy of the procedure has been carefully assessed. We present the derived set of corrected mode characteristics, which includes not only frequencies, but line widths, asymmetries, and amplitudes. We present and discuss their uncertainties and the precision of the ridge-to-mode correction schemes, through a detailed assessment of the sensitivity of the model to its input set. The precision of the ridge-to-mode correction is indicative of any possible residual systematic biases in the inferred mode characteristics. In our conclusions, we address how to further improve these estimates, and the implications for other data sets, like GONG+ and HMI.

Korzennik, S. G. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Rabello-Soares, M. C.; Schou, J.; Larson, T. P. [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States)

2013-08-01T23:59:59.000Z

202

HHFW Heating and Current Drive Studies of NSTX H-Mode Plasmas  

SciTech Connect (OSTI)

30 MHz high-harmonic fast wave (HHFW) heating and current drive are being developed to assist fully non-inductive plasma current (I{sub p}) ramp-up in NSTX. The initial approach to achieving this goal has been to heat I{sub p} = 300 kA inductive plasmas with current drive antenna phasing in order to generate an HHFW H-mode with significant bootstrap and RF-driven current. Recent experiments, using only 1.4 MW of RF power (P{sub RF}), achieved a noninductive current fraction, f{sub NI} {approx} 0.65. Improved antenna conditioning resulted in the generation of I{sub p} = 650 kA HHFW H-mode plasmas, with f{sub NI} {approx} 0.35, when P{sub RF} {ge} 2.5 MW. These plasmas have little or no edge localized mode (ELM) activity during HHFW heating, a substantial increase in stored energy and a sustained central electron temperature of 5-6 keV. Another focus of NSTX HHFW research is to heat an H-mode generated by 90 keV neutral beam injection (NBI). Improved HHFW coupling to NBI-generated H-modes has resulted in a broad increase in electron temperature profile when HHFW heating is applied. Analysis of a closely matched pair of NBI and HHFW+NBI H-mode plasmas revealed that about half of the antenna power is deposited inside the last closed flux surface (LCFS). Of the power damped inside the LCFS about two-thirds is absorbed directly by electrons and one-third accelerates fast-ions that are mostly promptly lost from the plasma. At longer toroidal launch wavelengths, HHFW+NBI H-mode plasmas can have an RF power flow to the divertor outside the LCFS that significantly reduces RF power deposition to the core. ELMs can also reduce RF power deposition to the core and increase power deposition to the edge. Recent full wave modeling of NSTX HHFW+NBI H-mode plasmas, with the model extended to the vessel wall, predicts a coaxial standing mode between the LCFS and the wall that can have large amplitudes at longer launch wavelengths. These simulation results qualitatively agree with HHFW+NBI H-mode data that show decreasing core RF heating efficiency and increasing RF power flow to the lower divertor at longer launch wavelengths.

G. Taylor, P.T. Bonoli, D.L. Green, R.W. Harvey, J.C. Hosea, E.F. Jaeger, B.P. LeBlanc, R. Maingi, C.K. Phillips, P.M. Ryan, E.J. Valeo, J.R. Wilson, J.C. Wright, and the NSTX Team

2011-06-08T23:59:59.000Z

203

HHFW Heating and Current Drive Studies of NSTX H-Mode Plasmas  

SciTech Connect (OSTI)

30 MHz high-harmonic fast wave (HHFW) heating and current drive are being developed to assist fully non-inductive plasma current (I{sub p}) ramp-up in NSTX. The initial approach to achieving this goal has been to heat I{sub p} = 300 kA inductive plasmas with current drive antenna phasing in order to generate an HHFW H-mode with significant bootstrap and RF-driven current. Recent experiments, using only 1.4 MW of RF power (P{sub RF}), achieved a non-inductive current fraction, f{sub NI}{approx}0.65. Improved antenna conditioning resulted in the generation of I{sub p} = 650 kA HHFW H-mode plasmas, with f{sub NI}{approx}0.35, when P{sub RF}{>=}2.5 MW. These plasmas have little or no edge localized mode (ELM) activity during HHFW heating, a substantial increase in stored energy and a sustained central electron temperature of 5-6 keV. Another focus of NSTX HHFW research is to heat an H-mode generated by 90 keV neutral beam injection (NBI). Improved HHFW coupling to NBI-generated H-modes has resulted in a broad increase in electron temperature profile when HHFW heating is applied. Analysis of a closely matched pair of NBI and HHFW+NBI H-mode plasmas revealed that about half of the antenna power is deposited inside the last closed flux surface (LCFS). Of the power damped inside the LCFS about two-thirds is absorbed directly by electrons and one-third accelerates fast-ions that are mostly promptly lost from the plasma. At longer toroidal launch wavelengths, HHFW+NBI H-mode plasmas can have an RF power flow to the divertor outside the LCFS that significantly reduces RF power deposition to the core. ELMs can also reduce RF power deposition to the core and increase power deposition to the edge. Recent full wave modeling of NSTX HHFW+NBI H-mode plasmas, with the model extended to the vessel wall, predicts a coaxial standing mode between the LCFS and the wall that can have large amplitudes at longer launch wavelengths. These simulation results qualitatively agree with HHFW+NBI H-mode data that show decreasing core RF heating efficiency and increasing RF power flow to the lower divertor at longer launch wavelengths.

Taylor, G.; Hosea, J. C.; LeBlanc, B. P.; Phillips, C. K.; Valeo, E. J.; Wilson, J. R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Bonoli, P. T.; Wright, J. C. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Green, D. L.; Jaeger, E. F.; Maingi, R.; Ryan, P. M. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Harvey, R. W. [CompX, PO Box 2672, Del Mar, California 92014 (United States)

2011-12-23T23:59:59.000Z

204

Growing drift-cyclotron modes in the hot solar atmosphere  

E-Print Network [OSTI]

Well-known analytical results dealing with ion cyclotron and drift waves and which follow from the kinetic theory are used and the dispersion equation, which describes coupled two modes, is solved numerically. The numerical results obtained by using the values for the plasma density, magnetic field and temperature applicable to the solar corona clearly show the coupling and the instability (growing) of the two modes. The coupling happens at very short wavelengths, that are of the order of the ion gyro radius, and for characteristic scale lengths of the equilibrium density that are altitude dependent and may become of the order of only a few meters. The demonstrated instability of the two coupled modes (driven by the equilibrium density gradient) is obtained by using a rigorous kinetic theory model and for realistic parameter values. The physical mechanism which is behind the coupling is simple and is expected to take place throughout the solar atmosphere and the solar wind which contain a variety of very elongated density structures of various sizes. The mode grows on account of the density gradient, it is essentially an ion mode, and its further dissipation should result in an increased ion heating.

J. Vranjes; S. Poedts

2008-05-31T23:59:59.000Z

205

Optical resonance modes in GaN pyramid microcavities  

SciTech Connect (OSTI)

An array of GaN hexagonal pyramids with a side length of 8.0 {mu}m was fabricated by selective epitaxial overgrowth. These microsized pyramids are highly efficient microcavities. Three types of optical resonance modes with mode spacings of 10, 5.0, and 6.0 {Angstrom} were observed when a single pyramid was pumped optically by an intense ultraviolet laser beam. An optical ray tracing method has been developed for calculating the optical resonance modes inside the pyramid microcavities. It was shown that a single pyramidal cavity can support several different types of optical resonance modes. The calculated mode spacing agrees very well with the observations. The uniqueness and advantages of this class of hexagonal pyramidal microcavities over the other microcavities are discussed. The implications of our finding on the future GaN microcavity light emitters including micro-light-emitting diodes, microcavity lasers, and vertical-cavity-surface emitting lasers are also discussed. {copyright} {ital 1999 American Institute of Physics.}

Jiang, H.X.; Lin, J.Y.; Zeng, K.C. [Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601 (United States)] [Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601 (United States); Yang, W. [Honeywell Technology Center, Plymouth, Minnesota 55441 (United States)] [Honeywell Technology Center, Plymouth, Minnesota 55441 (United States)

1999-08-01T23:59:59.000Z

206

Topological modes bound to dislocations in mechanical metamaterials  

E-Print Network [OSTI]

Mechanical metamaterials are artificial structures with unusual properties, such as negative Poisson ratio, bistability or tunable vibrational properties, that originate in the geometry of their unit cell. At the heart of such unusual behaviour is often a soft mode: a motion that does not significantly stretch or compress the links between constituent elements. When activated by motors or external fields, soft modes become the building blocks of robots and smart materials. Here, we demonstrate the existence of topological soft modes that can be positioned at desired locations in a metamaterial while being robust against a wide range of structural deformations or changes in material parameters. These protected modes, localized at dislocations, are the mechanical analogue of topological states bound to defects in electronic systems. We create physical realizations of the topological modes in prototypes of kagome lattices built out of rigid triangular plates. We show mathematically that they originate from the interplay between two Berry phases: the Burgers vector of the dislocation and the topological polarization of the lattice. Our work paves the way towards engineering topologically protected nano-mechanical structures for molecular robotics or information storage and read-out.

Jayson Paulose; Bryan Gin-ge Chen; Vincenzo Vitelli

2014-06-12T23:59:59.000Z

207

Interaction of fast particles and Alfven modes in burning plasmas  

SciTech Connect (OSTI)

In this paper we study the interaction of fast particles with Alfvenic instabilities in Tokamak plasmas, with reference to present-day experiments that exploit strong energetic particle heating (namely, JT-60U) and the consistency of proposed ITER burning plasma scenarios. Concerning JT-60U, two different types of bursting modes have been observed by MHD spectrography in auxiliary heated (NNB) discharges. One of these modes has been dubbed fast frequency sweeping (fast FS) mode. It is characterized by a timescale of the order of few milliseconds and frequencies branching upwards and downwards. The other mode, called the abrupt large-amplitude event (ALE), has shorter timescale (order of hundred microseconds) and larger amplitude. On the occurrence of ALEs, a significant reduction of the neutron emission rate in the central plasma region is observed. Such a change has been attributed to a redistribution of the energetic ions, with a marked reduction of their on-axis density. We present an interpretation of these experimental observations, based on the results of nonlinear particle simulations performed by the Hybrid MHD-Gyrokinetic Code HMGC.Concerning ITER, monotonic-q (scenario 2) and reversed-shear (scenario 4) equilibria are considered. Also an ITER hybrid scenario is examined and quantitatively compared with the previous ones. The transition from the low-amplitude Alfvenic instability saturation to the secondary excitation of a stronger mode is addressed, and its effect on the energetic particle transport analyzed.

Vlad, G.; Briguglio, S.; Fogaccia, G.; Zonca, F. [Associazione EURATOM-ENEA, CR ENEA-Frascati, Via E. Fermi 45, 00044 Frascati (Rome) (Italy)

2006-11-30T23:59:59.000Z

208

Mode coherence at megameter ranges in the North Pacific Ocean  

Science Journals Connector (OSTI)

This article analyzes the coherence of low-mode signals at ranges of 3515 and 5171 km using data from the Acoustic Thermometry of Ocean Climate (ATOC) and Alternate Source Test (AST) experiments. Vertical line arrays at Hawaii and Kiritimati received M-sequences transmitted from two sources: the 75-Hz bottom-mounted ATOC source on Pioneer Seamount and the near-axial dual-frequency (28/84 Hz) AST source deployed nearby. This study demonstrates that the characteristics of the mode signals at 5171-km range are quite similar to those at 3515-km range. At 75 Hz the mode time spreads are on the order of 1.5 s implying a coherence bandwidth of 0.67 Hz. The time spread of the 28-Hz signals is somewhat lower but these signals show significantly less frequency-selective fading than the 75-Hz signals suggesting that at the lower frequency the multipaths are temporally resolvable. Coherence times for mode 1 at 75 Hz are on the order of 8 min for the 3515-km range and 6 min for 5171-km range. At 28 Hz mode 1 is much more stable with a magnitude-squared coherence of greater than 0.6 for the 20-min transmission period.

Kathleen E. Wage; Matthew A. Dzieciuch; Peter F. Worcester; Bruce M. Howe; James A. Mercer

2005-01-01T23:59:59.000Z

209

Single-mode nonclassicality criteria via Holstein-Primakoff transformation  

E-Print Network [OSTI]

Recently, two quantifications for nonclassicality of a single-mode field are shown to be equivalent; (i) the rank of entanglement it can generate by a beam-splitter and (ii) the number of terms needed to expand it as superposition of coherent states. We show that nonclassicality criteria can be obtained with an alternative approach. The rank of two-mode entanglement among 2-level identical particles converges to the rank of single-mode nonclassicality within the Holstein-Primakoff transformation, at the large particle number limit. In particular, we show that the entanglement criterion of Hillery & Zubairy converges to the Mandel's $Q$-parameter which is used to reveal nonclassicality, and spin-squeezing criterion of S{\\o}rensen et al. converges to single-mode squeezing condition. We obtain additional nonclassicality criteria not existing in the literature. We also discuss if single-mode nonclassicality can be visualized as the entanglement of space generating the photons. Moreover, in a forthcoming study...

Tasgin, Mehmet Emre

2015-01-01T23:59:59.000Z

210

Effects of a random spatial variation of the plasma density on the mode conversion in cold, unmagnetized, and stratified plasmas  

SciTech Connect (OSTI)

We study the effects of a random spatial variation of the plasma density on the mode conversion of electromagnetic waves into electrostatic oscillations in cold, unmagnetized, and stratified plasmas. Using the invariant imbedding method, we calculate precisely the electromagnetic field distribution and the mode conversion coefficient, which is defined to be the fraction of the incident wave power converted into electrostatic oscillations, for the configuration where a numerically generated random density variation is added to the background linear density profile. We repeat similar calculations for a large number of random configurations and take an average of the results. We obtain a peculiar nonmonotonic dependence of the mode conversion coefficient on the strength of randomness. As the disorder increases from zero, the maximum value of the mode conversion coefficient decreases initially, then increases to a maximum, and finally decreases towards zero. The range of the incident angle in which mode conversion occurs increases monotonically as the disorder increases. We present numerical results suggesting that the decrease of mode conversion mainly results from the increased reflection due to the Anderson localization effect originating from disorder, whereas the increase of mode conversion of the intermediate disorder regime comes from the appearance of many resonance points and the enhanced tunneling between the resonance points and the cutoff point. We also find a very large local enhancement of the magnetic field intensity for particular random configurations. In order to obtain high mode conversion efficiency, it is desirable to restrict the randomness close to the resonance region.

Jung Yu, Dae [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of)] [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Kim, Kihong [Department of Energy Systems Research, Ajou University, Suwon 443-749 (Korea, Republic of)] [Department of Energy Systems Research, Ajou University, Suwon 443-749 (Korea, Republic of)

2013-12-15T23:59:59.000Z

211

Viscous damping of r-modes: Large amplitude saturation  

Science Journals Connector (OSTI)

We analyze the viscous damping of r-mode oscillations of compact stars, taking into account nonlinear viscous effects in the large-amplitude regime. The qualitatively different cases of hadronic stars, strange quark stars, and hybrid stars are studied. We calculate the viscous damping times of r-modes, obtaining numerical results and also general approximate analytic expressions that explicitly exhibit the dependence on the parameters that are relevant for a future spin-down evolution calculation. The strongly enhanced damping of large-amplitude oscillations leads to damping times that are considerably lower than those obtained when the amplitude dependence of the viscosity is neglected. Consequently, large-amplitude viscous damping competes with the gravitational instability at all physical frequencies and could stop the r-mode growth in case this is not done before by nonlinear hydrodynamic mechanisms.

Mark G. Alford; Simin Mahmoodifar; Kai Schwenzer

2012-02-22T23:59:59.000Z

212

Zero modes of six-dimensional Abelian vortices  

E-Print Network [OSTI]

We analyze the fluctuations of Nielsen-Olesen vortices arising in the six-dimensional Abelian-Higgs model. The regular geometry generated by the defect breaks spontaneously six-dimensional Poincar\\'e symmetry leading to a warped space-time with finite four-dimensional Planck mass. As a consequence, the zero mode of the spin two fluctuations of the geometry is always localized but the graviphoton fields, corresponding to spin one metric fluctuations, give rise to zero modes which are not localized either because of their behaviour at infinity or because of their behaviour near the core of the vortex. A similar situation occurs for spin zero fluctuations. Gauge field fluctuations exhibit a localized zero mode.

Massimo Giovannini; Jean-Vincent Le Be; Stephane Riederer

2002-05-21T23:59:59.000Z

213

Asymmetric tearing mode in the presence of viscosity  

SciTech Connect (OSTI)

The linear stability of the tearing mode (TM) in a plasma column is investigated in the presence of viscosity and finite equilibrium current density gradients (i.e., asymmetries). It is shown that for low {beta}, both effects are essential in order to properly describe the mode behaviour close to marginality. In particular, the theory introduces a critical threshold for the destabilization, such that the perturbation grows only if {Delta}'>{Delta}'{sub cr}. The value of {Delta}'{sub cr} depends on the equilibrium configuration and on the plasma parameters. Most importantly, {Delta}'{sub cr} can take negative values, thus allowing unstable tearing modes for {Delta}' < 0 (even in the absence of bootstrap current).

Militello, F. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Borgogno, D. [Dipartimento di Energetica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy); Grasso, D. [CNR Consiglio Nazionale delle Ricerche, Istituto dei Sistemi Complessi, Dipartimento di Energetica, Politecnico di Torino, 10129 Torino (Italy); Marchetto, C. [Associazione EURATOM-ENEA sulla Fusione, IFP-CNR, Via R. Cozzi 53, 20125 Milano (Italy); Ottaviani, M. [Association EURATOM-CEA, CEA/DSM/IRFM, CEA Cadarache, 13108 St. Paul-lez-Durance (France)

2011-11-15T23:59:59.000Z

214

Lasing modes in polycrystalline and amorphous photonic structures  

SciTech Connect (OSTI)

We systematically studied the lasing characteristics in photonic polycrystalline and amorphous structures. 2D arrays of air holes were fabricated in a GaAs membrane. InAs quantum dots embedded in the membrane provide gain for lasing under optical pumping. The lasing modes are spatially localized, and blue shift as the structural order becomes short ranged. Our three-dimensional numerical simulations reveal that the out-of-plane leakage of the lasing mode dominates over the in-plane leakage. The lasing modes in a photonic polycrystalline move away from the center frequency of the photonic band gap to reduce the out-of-plane leakage. In a photonic amorphous structure, the short-range order improves optical confinement and enhances the quality factor of resonances. Understanding the behavior of photonic polycrystalline laser and amorphous laser opens the possibility of controlling lasing characteristic by varying the degree of structural order.

Yang, Jin-Kyu [Department of Applied Physics, Yale University, New Haven, Connecticut 06520 (United States); Department of Optical Engineering, Kongju National University, Kongju 314-701 (Korea, Republic of); Noh, Heeso; Liew, Seng Fatt; Rooks, Michael J. [Department of Applied Physics, Yale University, New Haven, Connecticut 06520 (United States); Solomon, Glenn S. [Joint Quantum Institute, NIST and University of Maryland, Gaithersburg, Maryland 20899 (United States); Cao Hui [Department of Applied Physics, Yale University, New Haven, Connecticut 06520 (United States); Department of Physics, Yale University, New Haven, Connecticut 06520 (United States)

2011-09-15T23:59:59.000Z

215

Linear mode conversion of Langmuir/z-mode waves to radiation in plasmas with various magnetic field strength  

SciTech Connect (OSTI)

Linear mode conversion of Langmuir/z waves to electromagnetic radiation near the plasma and upper hybrid frequency in the presence of density gradients is potentially relevant to type II and III solar radio bursts, ionospheric radar experiments, pulsars, and continuum radiation for planetary magnetospheres. Here, we study mode conversion in warm, magnetized plasmas using a numerical electron fluid simulation code when the density gradient has a wide range of angle, ?, to the ambient magnetic field, B{sub 0}, for a range of incident Langmuir/z wavevectors. Our results include: (1) Left-handed polarized ordinary (oL) and right-handed polarized extraordinary (xR) mode waves are produced in various ranges of ? for ?{sub 0} = (?L/c){sup 1/3}(?{sub ce}/?) < 1.5, where ?{sub ce} is the (angular) electron cyclotron frequency, ? is the angular wave frequency, L is the length scale of the (linear) density gradient, and c is the speed of light; (2) the xR mode is produced most strongly in the range, 40 < ? < 60, for intermediately magnetized plasmas with ?{sub 0} = 1.0 and 1.5, while it is produced over a wider range, 0 ? ? ? 90, for weakly magnetized plasmas with ?{sub 0} = 0.1 and 0.7; (3) the maximum total conversion efficiencies for wave power from the Langmuir/z mode to radiation are of order 50%99% and the corresponding energy conversion efficiencies are 5%14% (depending on the adiabatic index ? and ? = T{sub e}/m{sub e}c{sup 2}, where T{sub e} is the electron temperature and m{sub e} is the electron) for various ?{sub 0}; (4) the mode conversion window becomes wider as ?{sub 0} and ? increase. Hence, the results in this paper confirm that linear mode conversion under these conditions can explain the weak total circular polarization of interplanetary type II and III solar radio bursts because a strong xR mode can be generated via linear mode conversion near ? ? 45.

Kim, Eun-Hwa; Johnson, Jay R. [Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)] [Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Cairns, Iver H. [School of Physics, University of Sydney, Sydney, New South Wales 2002 (Australia)] [School of Physics, University of Sydney, Sydney, New South Wales 2002 (Australia)

2013-12-15T23:59:59.000Z

216

Ballooning Modes in the Systems Stabilized by Divertors  

SciTech Connect (OSTI)

MHD stability of a plasma in systems with closed magnetic field lines and open systems containing the nonparaxial stabilizing cells with large field lines curvature, in particular, divertors is analyzed. It is shown that population of particles trapped in such cells has a stabilizing effect not only on flute modes, but also on ballooning modes that determine the {beta} limit. At kinetic description that accounts for different effect of trapped and passing particles on perturbations, {beta} limit permitted by stability may be much greater then it follows from MHD model.

Arsenin, V.V.; Skovoroda, A.A.; Zvonkov, A.V. [Nuclear Fusion Institute, RRC Kurchatov Institute (Russian Federation)

2005-01-15T23:59:59.000Z

217

Wind Turbine Gearbox Failure Modes - A Brief (Presentation)  

SciTech Connect (OSTI)

Wind turbine gearboxes are not always meeting 20-year design life. Premature failure of gearboxes increases cost of energy, turbine downtime, unplanned maintenance, gearbox replacement and rebuild, and increased warranty reserves. The problem is widespread, affects most Original Equipment Manufacturers, and is not caused by manufacturing practices. There is a need to improve gearbox reliability and reduce turbine downtime. The topics of this presentation are: GRC (Gearbox Reliability Collaborative) technical approach; Gearbox failure database; Recorded incidents summary; Top failure modes for bearings; Top failure modes for gears; GRC test gearbox; Bearing nomenclature; Test history; Real damage; Gear sets; Bearings; Observations; and Summary. 5 refs.

Sheng, S.; McDade, M.; Errichello, R.

2011-10-01T23:59:59.000Z

218

Purcell factor of Mie resonators featuring electric and magnetic modes  

E-Print Network [OSTI]

We present a modal approach to compute the Purcell factor in Mie resonators exhibiting both electric and magnetic resonances. The analytic expressions of the normal modes are used to calculate the effective volumes. We show that important features of the effective volume can be predicted thanks to the translation-addition coefficients of a displaced dipole. Using our formalism, it is easy to see that, in general, the Purcell factor of Mie resonators is not dominated by a single mode, but rather by a large superposition. Finally we consider a silicon resonator homogeneously doped with electric dipolar emitters, and we show that the average electric Purcell factor dominates over the magnetic one.

Zambrana-Puyalto, Xavier

2015-01-01T23:59:59.000Z

219

Wavelength meter having single mode fiber optics multiplexed inputs  

DOE Patents [OSTI]

A wavelength meter having a single mode fiber optics input is disclosed. The single mode fiber enables a plurality of laser beams to be multiplexed to form a multiplexed input to the wavelength meter. The wavelength meter can provide a determination of the wavelength of any one or all of the plurality of laser beams by suitable processing. Another aspect of the present invention is that one of the laser beams could be a known reference laser having a predetermined wavelength. Hence, the improved wavelength meter can provide an on-line calibration capability with the reference laser input as one of the plurality of laser beams.

Hackel, R.P.; Paris, R.D.; Feldman, M.

1993-02-23T23:59:59.000Z

220

Geiger-Mode Avalanche Photodiodes in Particle Detection  

E-Print Network [OSTI]

It is well known that avalanche photodiodes operated in the Geiger mode above the breakdown voltage offer a virtually infinite sensitivity and time accuracy in the picosecond range that can be used for single photon detection. However, their performance in particle detection remains still unexplored. In this contribution, we are going to expose the different steps that we have taken in order to prove the efficiency of Geiger mode avalanche photodiodes in the aforementioned field. In particular, we will present an array of pixels of 1mmx1mm fabricated with a standard CMOS technology for characterization in a test beam.

E. Vilella; O. Alonso; J. Trenado; A. Vil; M. Vos; L. Garrido; A. Diguez

2012-01-27T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


221

Are "EIT Waves" Fast-Mode MHD Waves?  

E-Print Network [OSTI]

We examine the nature of large-scale, coronal, propagating wave fronts (``EIT waves'') and find they are incongruous with solutions using fast-mode MHD plane-wave theory. Specifically, we consider the following properties: non-dispersive single pulse manifestions, observed velocities below the local Alfven speed, and different pulses which travel at any number of constant velocities, rather than at the ``predicted'' fast-mode speed. We discuss the possibility of a soliton-like explanation for these phenomena, and show how it is consistent with the above-mentioned aspects.

M. J. Wills-Davey; C. E. DeForest; J. O. Stenflo

2007-04-23T23:59:59.000Z

222

Wavelength meter having single mode fiber optics multiplexed inputs  

DOE Patents [OSTI]

A wavelength meter having a single mode fiber optics input is disclosed. The single mode fiber enables a plurality of laser beams to be multiplexed to form a multiplexed input to the wavelength meter. The wavelength meter can provide a determination of the wavelength of any one or all of the plurality of laser beams by suitable processing. Another aspect of the present invention is that one of the laser beams could be a known reference laser having a predetermined wavelength. Hence, the improved wavelength meter can provide an on-line calibration capability with the reference laser input as one of the plurality of laser beams.

Hackel, Richard P. (Livermore, CA); Paris, Robert D. (San Ramon, CA); Feldman, Mark (Pleasanton, CA)

1993-01-01T23:59:59.000Z

223

A Non-radial Oscillation Mode in an Accreting Millisecond Pulsar?  

Science Journals Connector (OSTI)

We present results of targeted searches for signatures of non-radial oscillation modes (such as r- and g-modes) in neutron stars using RXTE data from several accreting millisecond X-ray pulsars (AMXPs). We search for potentially coherent signals in the neutron star rest frame by first removing the phase delays associated with the star's binary motion and computing fast Fourier transform power spectra of continuous light curves with up to 230 time bins. We search a range of frequencies in which both r- and g-modes are theoretically expected to reside. Using data from the discovery outburst of the 435Hz pulsar XTE J1751305 we find a single candidate, coherent oscillation with a frequency of 0.5727597 ? ?spin = 249.332609Hz, and a fractional Fourier amplitude of 7.46 ? 104. We estimate the significance of this feature at the 1.6 ? 103 level, slightly better than a 3? detection. Based on the observed frequency we argue that possible mode identifications include rotationally modified g-modes associated with either a helium-rich surface layer or a density discontinuity due to electron captures on hydrogen in the accreted ocean. In the latter case the presence of sufficient hydrogen in this ultracompact system with a likely helium-rich donor would present an interesting puzzle. Alternatively, the frequency could be identified with that of an inertial mode or a core r-mode modified by the presence of a solid crust; however, the r-mode amplitude required to account for the observed modulation amplitude would induce a large spin-down rate inconsistent with the observed pulse timing measurements. For the AMXPs XTE J1814338 and NGC6440 X2 we do not find any candidate oscillation signals, and we place upper limits on the fractional Fourier amplitude of any coherent oscillations in our frequency search range of 7.8 ? 104 and 5.6 ? 103, respectively. We briefly discuss the prospects and sensitivity for similar searches with future, larger X-ray collecting area missions.

Tod Strohmayer; Simin Mahmoodifar

2014-01-01T23:59:59.000Z

224

Measurement of correlations between low-frequency vibrational modes and particle rearrangements in quasi-two-dimensional colloidal glasses  

E-Print Network [OSTI]

We investigate correlations between low-frequency vibrational modes and rearrangements in two-dimensional colloidal glasses composed of thermosensitive microgel particles which readily permit variation of sample packing fraction. At each packing fraction, the particle displacement covariance matrix is measured and used to extract the vibrational spectrum of the "shadow" colloidal glass (i.e., the particle network with the same geometry and interactions as the sample colloid but absent damping). Rearrangements are induced by successive, small reductions in packing fraction. The experimental results suggest that low-frequency quasi-localized phonon modes in colloidal glasses, i.e., modes that present low energy barriers for system rearrangements, are spatially correlated with rearrangements in this thermal system.

K. Chen; M. L. Manning; P. J. Yunker; W. G. Ellenbroek; Z. Zhang; Andrea J. Liu; A. G. Yodh

2011-03-11T23:59:59.000Z

225

Origin of the high-energy Raman modes in single-wall carbon nanotubes  

E-Print Network [OSTI]

Origin of the high-energy Raman modes in single-wall carbon nanotubes J. Maultzsch, C. Thomsen, S nanotubes. Similar to the disorder-induced D mode, the high-energy modes are deter- mined by double of the first-order high-energy Raman modes in carbon nanotubes has been a puzzling question since the first

Nabben, Reinhard

226

Northwest Energy Innovations (TRL 5 6 System)- WETNZ MtiMode Wave Energy Converter Advancement Project  

Broader source: Energy.gov [DOE]

Northwest Energy Innovations (TRL 5 6 System) - WETNZ MtiMode Wave Energy Converter Advancement Project

227

Dynamics of Tearing Modes during Strong Electron Cyclotron Heating on the FTU Tokamak  

Science Journals Connector (OSTI)

The localized electron cyclotron resonance heating power that can suppress sawteeth reconnection often drives m=2 tearing modes in a tokamak operating at constant current. The dynamics of mode onset and coupled mode evolution is described in detail and compared with a nonlinear theoretical model that identifies the effects of mode coupling, finite inertia of the rotating islands, and wall braking.

E. Lazzaro et al.

2000-06-26T23:59:59.000Z

228

Nonlinear Simulations of Peeling-Ballooning Modes with Anomalous Electron Viscosity and their Role in Edge Localized Mode Crashes  

SciTech Connect (OSTI)

A minimum set of equations based on the peeling-ballooning (P-B) model with nonideal physics effects (diamagnetic drift, ExB drift, resistivity, and anomalous electron viscosity) is found to simulate pedestal collapse when using the new BOUT++ simulation code, developed in part from the original fluid edge code BOUT. Nonlinear simulations of P-B modes demonstrate that the P-B modes trigger magnetic reconnection, which leads to the pedestal collapse. With the addition of a model of the anomalous electron viscosity under the assumption that the electron viscosity is comparable to the anomalous electron thermal diffusivity, it is found from simulations using a realistic high-Lundquist number that the pedestal collapse is limited to the edge region and the edge localized mode (ELM) size is about 5%-10% of the pedestal stored energy. This is consistent with many observations of large ELMs.

Xu, X. Q.; Umansky, M. V. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dudson, B.; Wilson, H. [University of York, Heslington, York YO10 5DD (United Kingdom); Snyder, P. B. [General Atomics, San Diego, California 92186 (United States)

2010-10-22T23:59:59.000Z

229

Prep mode rack kits for Frac-950 Instructions  

E-Print Network [OSTI]

Prep mode rack kits for Frac-950 Instructions Edition AB 56-3153-30 Installing the rack Assembling the rack Make sure that the guide pin fits! Place the guide pin legs at the side with the bulge! 1 2 3

Pawlowski, Wojtek

230

Bulk viscosity and r-modes of neutron stars  

E-Print Network [OSTI]

The bulk viscosity due to the non-leptonic process involving hyperons in $K^-$ condensed matter is discussed here. We find that the bulk viscosity is modified in a superconducting phase. Further, we demonstrate how the exotic bulk viscosity coefficient influences $r$-modes of neutron stars which might be sources of detectable gravitational waves.

Debarati Chatterjee; Debades Bandyopadhyay

2008-08-08T23:59:59.000Z

231

CRYOGENIC SYSTEM FOR CONTINUOUS ULTRAHIGH HYDROGEN PURIFICATION IN CIRCULATION MODE  

E-Print Network [OSTI]

1 CRYOGENIC SYSTEM FOR CONTINUOUS ULTRAHIGH HYDROGEN PURIFICATION IN CIRCULATION MODE A. Vasilyev1, the total level of all contaminants (water, nitrogen, oxygen etc.) has to be lower than 0.01 ppm. Hydrogen preparation by commercial purification units, such as palladium filters, could give a good initial level

Kammel, Peter

232

Pulsar emission: Langmuir modes in a relativistic multicomponent plasma  

Science Journals Connector (OSTI)

......of magnitude larger than mode wavelengths...ion-proton plasma Lorentz factors...moderately large and would give...order of 1-MHz. The components of the plasma are of particular...two-component atmosphere in local thermodynamic...radiation from an area of the neutron-star......

P. B. Jones

2014-01-01T23:59:59.000Z

233

SHIFTING MODES? TRANSPORTATION AND URBAN DEVELOPMENT PATTERNS IN  

E-Print Network [OSTI]

Shares (%) ­ Journey to Work, US (varies by region) Drive alone Carpool Transit Walk #12;More data Elizabeth Deakin Professor of City and Regional Planning University of California, Berkeley March 5, 2011 & saving energy in transport via mode shifts? Prospects for the future #12;I - Factors affecting travel

Kammen, Daniel M.

234

Early-stage Power Grid Analysis for Uncertain Working Modes  

E-Print Network [OSTI]

Early-stage Power Grid Analysis for Uncertain Working Modes Haifeng Qian Department of ECE circuits are now reaching the 100-plus watt regime, and power delivery and power grid signal integrity have and Design Aids General Terms Algorithms, Performance, Design, Reliability Keywords Power grid, Supply

Sapatnekar, Sachin

235

Localized mode interactions in 0-Josephson junctions Hadi Susanto1  

E-Print Network [OSTI]

Localized mode interactions in 0- Josephson junctions Hadi Susanto1 and Gianne Derks2 1 School of Mathematics, University of Surrey, Guildford, Surrey, GU2 7XH, UK A long Josephson junction containing regions in the system, it is shown that Josephson junctions with phase-shift can be an ideal setting for studying

Wirosoetisno, Djoko

236

Robust Neural Sliding Mode Control of Robot Manipulators  

SciTech Connect (OSTI)

This paper proposes a robust neural sliding mode control method for robot tracking problem to overcome the noises and large uncertainties in robot dynamics. The Lyapunov direct method has been used to prove the stability of the overall system. Simulation results are given to illustrate the applicability of the proposed method.

Nguyen Tran Hiep [Le Quy Don University Hanoi-Vietnam (Viet Nam); Pham Thuong Cat [Institute of Information Technology, Academy of Science and Technology Vietnam (Viet Nam)

2009-03-05T23:59:59.000Z

237

Molecular Cell Mode of Regulation and the Insulation  

E-Print Network [OSTI]

Molecular Cell Article Mode of Regulation and the Insulation of Bacterial Gene Expression Vered.molcel.2012.04.032 SUMMARY A gene can be said to be insulated from environ- mental variations if its the insulation of the lac promoter of E. coli and of synthetic constructs in which the transcription factor CRP

238

Stabilization of ballooning modes with sheared toroidal rotation  

SciTech Connect (OSTI)

Stabilization of magnetohydrodynamic ballooning modes by sheared toroidal rotation is demonstrated using a shifted circle equilibrium model. A generalized ballooning mode representation is used to eliminate the fast Alfven wave, and an initial value code solves the resulting equations. The {ital s}{minus}{alpha} diagram (magnetic shear versus pressure gradient) of ballooning mode theory is extended to include rotational shear. In the ballooning representation, the modes shift periodically along the field line to the next point of unfavorable curvature. The shift frequency ({ital d}{Omega}/{ital dq}, where {Omega} is the angular toroidal velocity and {ital q} is the safety factor) is proportional to the rotation shear and inversely proportional to the magnetic shear. Stability improves with increasing shift frequency and direct stable access to the second stability regime occurs when this frequency is approximately one-quarter to one-half the Alfven frequency, {omega}{sub A}={ital V}{sub A}/{ital qR}. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Miller, R.L.; Waelbroeck, F.L.; Hassam, A.B.; Waltz, R.E. [General Atomics, San Diego, California 92186-9784 (United States)] [General Atomics, San Diego, California 92186-9784 (United States)

1995-10-01T23:59:59.000Z

239

Simulations of solar cell absorption enhancement using resonant modes  

E-Print Network [OSTI]

Simulations of solar cell absorption enhancement using resonant modes of a nanosphere array Jonathan Grandidier Michael G. Deceglie Dennis M. Callahan Harry A. Atwater #12;Simulations of solar cell for enhancing the absorption of thin-film amorphous silicon solar cells using periodic arrangements of resonant

Grandidier, Jonathan

240

Sliding Mode Control of EV Electric Differential System  

E-Print Network [OSTI]

of an electric differential system for Electric Vehicle (EV) with two induction motor drives (one for each wheel of electric drives to control the generated torque and the introduction of an independent control400 1 Sliding Mode Control of EV Electric Differential System A. Haddoun, M. E. H. Benbouzid, D

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "modes mode fraction" 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

Failure Modes and Effects Analysis 300 Array -LRRR  

E-Print Network [OSTI]

of the Failure Modes and Effects Analysis (FMEA) is to discover critical failure areas in a system and to remove failure areas. 1. 2 This memo contains the results of the final FMEA for the 300 Array LRRR experiment was successfully deployed on the moon as a part of the Apollo 11 mission, this FMEA will not dwell in the aspects

Rathbun, Julie A.

242

Combining failure mode and functional resonance analyses in healthcare settings  

Science Journals Connector (OSTI)

Socio-technical systems rely on technological artefacts as well as human and professional practices in order to achieve organisational safety. From an organisational viewpoint of analysis, different safety barriers are often put in place in order to ... Keywords: failure mode and effects analysis (FMEA), functional resonance analysis method (FRAM), healthcare

Mark-Alexander Sujan; Massimo Felici

2012-09-01T23:59:59.000Z

243

NO. ~EV. NO. Failure Modes and Effects Analysis -LRRR  

E-Print Network [OSTI]

of the Failure Modes and Effects Analysis (FMEA) is to discover critical failure areas in the LRRR experiment for the critical failure areas. A TM 868 contains the results of a final FMEA for the LRRR experiment. 2. 0 SUMMARY Since an LRRR was successfully deployed on the moon as a part of the Apollo 11 mission, this FMEA

Rathbun, Julie A.

244

EVALUATION OF COMPONENT MODE SYNTHESIS METHODS FOR THE  

E-Print Network [OSTI]

EVALUATION OF COMPONENT MODE SYNTHESIS METHODS FOR THE DETECTION OF MODAL INTERACTION THROUGH ROTOR 2009 Abstract The study of interactions through direct contact between blade-tips and outer casings where friction is accounted for. This method offers energy momentum conserving which is a critical point

Boyer, Edmond

245

Salt Repository Project waste emplacement mode decision paper: Revison 1  

SciTech Connect (OSTI)

This paper provides a recommendation as to the mode of waste emplacement to be used as the current basis for site characterization activity for the Deaf Smith County, Texas, high level nuclear waste repository site. It also presents a plan for implementing the recommendation so as to provide a high level of confidence in the project's success. Since evaluations of high-level waste disposal in geologic repositories began in the 1950s, most studies emplacement in salt formations employed the vertical orientation for emplacing waste packages in boreholes in the floor of the underground facility. This orientation was used in trials at Project Salt Vault in the 1960s. The Waste Isolation Pilot Plant (WIPP) has recently settled on a combination of vertical and horizontal modes for various waste types. This paper analyzes the information available and develops a project position upon which to base current site characterization activities. The position recommended is that the SRP should continue to use the vertical waste emplacement mode as the reference design and to carry the horizontal mode as a ''passive'' alternative. This position was developed based upon the conclusions of a decision analysis, risk assessment, and cost/schedule impact assessment. 52 refs., 6 figs., 1 tab.

Not Available

1987-08-01T23:59:59.000Z

246

Fundamental oscillation modes of neutron stars: validity of universal relations  

E-Print Network [OSTI]

We study the $f$-mode frequencies and damping times of nonrotating neutron stars (NS) in general relativity (GR) by solving the linearized perturbation equations, with the aim to establish "universal" relations that depend only weakly on the equations of state (EOS). Using a more comprehensive set of EOSs, we re-examine some proposed linearizations that describe the $f$-mode parameters in terms of mass and radius of the neutron star (NS), and we test a more recent proposal for expressing the $f$-mode parameters as quadratic functions of the effective compactness. Our extensive results for each equation of state considered allow us to study the accuracy of each proposal. In particular, we find that the damping time deviates quite considerably from the proposed linearization. We introduce a new universal relation for the product of the $f$-mode frequency and damping time as a function of the (ordinary) compactness, which proved to be more accurate. The relations using the effective compactness on the other hand...

Chirenti, Cecilia; Kastaun, Wolfgang

2015-01-01T23:59:59.000Z

247

Energy Minimization in Cooperative Relay Networks with Sleep Modes  

E-Print Network [OSTI]

. To minimize the total energy consumption, working modes of RNs and power allocation need to be optimized dominates the total energy consumption only when the transmission range is long. As wireless net- works consumption model, the total energy con- sumption consists of transmission energy and circuit energy

Paris-Sud XI, Université de

248

Oddelek za ziko Normal modes in the atmosphere  

E-Print Network [OSTI]

weather prediction. In section 3 I concentrate on the normal modes of a very simple model, shallow water #12;Numerical weather prediction is an initial condition problem. That means we need ini- tial-gravity waves just play their role, but in numerical models of the atmosphere, they can cause huge problems. 1

?umer, Slobodan

249

Kinetic Properties of Alfven Modes in Tokamak Plasmas  

SciTech Connect (OSTI)

The ability to predict the stability of fast-particle-driven Alfven eigenmodes in burning fusion plasmas requires a detailed understanding of the dissipative mechanisms that damp these modes. In order to address this question, the linear gyro-kinetic, electromagnetic code LIGKA is employed to investigate their behaviour in realistic tokamak geometry. The eigenvalue formulation of LIGKA allows to calculate self-consistently the coupling of large-scaled MHD modes to the gyroradius scale-length kinetic Alfven waves. Therefore, the properties of the kineticly modified TAE mode in or near the gap (KTAE, radiative damping or 'tunnelling') and its coupling to the continuum close to the edge can be analysed numerically. In addition, an antenna-like version of LIGKA allows for a frequency scan, analogous to an external antenna.The model and the implementation of LIGKA were recently extended in order to capture the coupling of the shear Alfven waves to the sound waves. This coupling becomes important for the investigation of kinetic effects on the low-frequency phase of cascade modes, where e.g. geodesic acoustic effects play a significant role.

Lauber, Ph.; Guenter, S.; Bruedgam, M. [Max-Planck-Institut fuer Plasmaphysik, EURATOM-Association, D-85748 Garching (Germany); Koenies, A. [Max-Planck Institut fuer Plasmaphysik, EURATOM-Association, D-17489 Greifswald (Germany); Pinches, S. D. [UKAEA Fusion Association Culham Science Centre, Abingdon, Oxfordshire OX143DB (United Kingdom)

2006-11-30T23:59:59.000Z

250

Dynamic Modes of Nanoparticle Motion During Nanoprobe-based Manipulation  

E-Print Network [OSTI]

Dynamic Modes of Nanoparticle Motion During Nanoprobe-based Manipulation Afshin Tafazzoli and Metin -- In this paper, dynamic behavior of nanoparticle motion during nanoprobe-based manipulation is investigated behavior of nanoparticles. This would benefit us on tribological characterization of materials. Index Terms

Sitti, Metin

251

Issue 412 May 2014 Autoflight control modes generally involve interrelated  

E-Print Network [OSTI]

. Myth Versus Truth Failure to notice that the autoflight system has not sequenced to the Approach mode can have serious consequences if the crew is not monitoring other critical information Controller are myth and what displays on the PFD (Primary Flight Display) is truth. In other words, I can

252

Review of Mode-Conversion Calculations in Toroidal Plasmasy  

E-Print Network [OSTI]

Institute of Technology SE-100 44 Stockholm, Sweden y work performed during a visit at CRPP, september 1999 ABSTRACT. Recent developments in the gyrokinetic modeling of drift-, Alfv´en and Bernstein waves allow-hybrid resonances where mode-conversion is possible; the power absorption can however not cor- rectly be determined

Jaun, André

253

Review of ModeConversion Calculations in Toroidal Plasmas y  

E-Print Network [OSTI]

Institute of Technology SE­100 44 Stockholm, Sweden y work performed during a visit at CRPP, september 1999 ABSTRACT. Recent developments in the gyrokinetic modeling of drift­, Alfv??en and Bernstein waves allow­hybrid resonances where mode­conversion is possible; the power absorption can however not cor­ rectly be determined

Jaun, André

254

Numerical Investigation of Leaky-Mode Coupling in VCSELs  

SciTech Connect (OSTI)

We investigate various aspects of leaky-mode coupling behavior in Vertical-Cavity Surface-Emitting Lasers (VCSELs) using a 2D finite difference model to simulate two coupled pixels. Phase-locking is shown to occur in a manner consistent with previous simple models.

Hadley, G. R.

1997-12-31T23:59:59.000Z

255

Vibration Control of Multi-Mode Rotor-Bearing Systems  

Science Journals Connector (OSTI)

8 March 1983 research-article Vibration Control of Multi-Mode Rotor-Bearing...least-squares method to minimize the vibration of any general rotor-bearing system...to implement the open-loop adaptive vibration control strategies outlined in the paper...

1983-01-01T23:59:59.000Z

256

Array E PCU Failure Modes, Effects and Criticality Analysis ,...  

E-Print Network [OSTI]

, this circuit would automatically switch power to the redundant unit. 2. 2 INVERTER MODULE ,· The Inverter the Failure Modes, Effect and Criticality Analysis on the Bendix designed Power Con- ditioning Unit resulted in IOOo/o success on all previ- ous arrays plus the following new features: I. Complete Redundancy

Rathbun, Julie A.

257

Vibrational modes of a rotating string Theodore J. Allen  

E-Print Network [OSTI]

find the small amplitude oscillatory motions and frequencies of oscillation of the string and mass. WeVibrational modes of a rotating string Theodore J. Allen Department of Physics, University Motivated by non-relativistic models of a QCD string, we examine the system of a non-relativistic string

Allen, Theodore J.

258

Vibrational modes of a rotating string Theodore J. Allen  

E-Print Network [OSTI]

find the small amplitude oscillatory motions and frequencies of oscillation of the string and mass. WeVibrational modes of a rotating string Theodore J. Allen Department of Physics, University Motivated by non­relativistic models of a QCD string, we examine the system of a non­relativistic string

Allen, Theodore J.

259

Passive mode control in the recirculating planar magnetron  

SciTech Connect (OSTI)

Preliminary experiments of the recirculating planar magnetron microwave source have demonstrated that the device oscillates but is susceptible to intense mode competition due, in part, to poor coupling of RF fields between the two planar oscillators. A novel method of improving the cross-oscillator coupling has been simulated in the periodically slotted mode control cathode (MCC). The MCC, as opposed to a solid conductor, is designed to electromagnetically couple both planar oscillators by allowing for the propagation of RF fields and electrons through resonantly tuned gaps in the cathode. Using the MCC, a 12-cavity anode block with a simulated 1 GHz and 0.26 c phase velocity (where c is the speed of light) was able to achieve in-phase oscillations between the two sides of the device in as little as 30 ns. An analytic study of the modified resonant structure predicts the MCC's ability to direct the RF fields to provide tunable mode separation in the recirculating planar magnetron. The self-consistent solution is presented for both the degenerate even (in phase) and odd (180 Degree-Sign out of phase) modes that exist due to the twofold symmetry of the planar magnetrons.

Franzi, Matthew; Gilgenbach, Ronald; Lau, Y. Y.; Greening, Geoff; Zhang, Peng [Plasma, Pulsed Power, and Microwave Laboratory, Nuclear Engineering and Radiological Sciences Department, University of Michigan, Ann Arbor, Michigan 48109-2104 (United States); Hoff, Brad [Air Force Research Laboratory, Kirtland AFB, New Mexico 87117 (United States)

2013-03-15T23:59:59.000Z

260

SP 800-38B. Recommendation for Block Cipher Modes of Operation: the CMAC Mode for Authentication  

Science Journals Connector (OSTI)

This Recommendation specifies a message authentication code (MAC) algorithm based on a symmetric key block cipher. This block cipher-based MAC algorithm, called CMAC, may be used to provide assurance of the authenticity and, hence, the integrity of binary ... Keywords: Authentication, block cipher, cryptography, information security, integrity, message authentication code, mode of operation.

Morris J. Dworkin

2005-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

The Light Curve and Internal Magnetic Field of the Mode-Switching Pulsar PSR B0943+10  

E-Print Network [OSTI]

A number of radio pulsars exhibit intriguing mode-switching behavior. Recent observations of PSR B0943+10 revealed correlated radio and X-ray mode switches, providing a new avenue for understanding this class of objects. The large X-ray pulse fraction observed during the radio quiet phase (Q mode) was previously interpreted as a result of changing obscuration of X-rays by dense magnetosphere plasma. We show that the large X-ray pulse fraction can be explained by including the beaming effect of a magnetic atmosphere, while remaining consistent with the dipole field geometry constrained by radio observations. We also explore a more extreme magnetic field configuration, where a magnetic dipole displaced from the center of the star produces two magnetic polar caps of different sizes and magnetic field strengths. These models are currently consistent with data in radio and X-rays and can be tested or constrained by future X-ray observations.

Storch, Natalia I; Lai, Dong; Bogdanov, Slavko; Heinke, Craig O

2014-01-01T23:59:59.000Z

262

CERTS 2012 Program Review - Mode Meter Development - Ning Zhou, PNNL  

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

Presented by: Ning Zhou Presented by: Ning Zhou 1 Pacific Northwest National Laboratory June 12 th , 2012 Washington DC Work Team PNNL team: Ning Zhou Pengwei Du Jim Follum (summer intern) The work under this project closely aligns and collaborates with the research under the TRP project "Measurement Based Stability Assessment" being conducted by: Dan Trudnowski, Montana Tech John Pierre, University of Wyoming Louis Scharf, Colorado State University (Retired) Many graduate students 2 Project Objective: Real Time Mode Identification 3 Goal: Enhance the power system reliability by estimating oscillation modes from PMU data in near real time. Technical Approaches: Modal Analysis from Ringdown Data 4 1. Detect Ringdown 2. Select Channels 3. Modal Analysis

263

Can decaying modes save void models for acceleration?  

Science Journals Connector (OSTI)

The discovery of the unexpected dimness of typeIa supernovae, apparently due to accelerated expansion driven by some form of dark energy or modified gravity, has led to attempts to explain the observations using only general relativity with baryonic and cold dark matter, but by dropping the standard assumption of homogeneity on Hubble scales. In particular, the supernova data can be explained if we live near the center of a Hubble-scale void. However, such void models have been shown to be inconsistent with various observations, assuming the void consists of a pure growing mode. Here it is shown that models with significant decaying mode contribution today can be ruled out on the basis of the expected cosmic microwave background spectral distortion. This essentially closes one of the very few remaining loopholes in attempts to rule out void models, and strengthens the evidence for Hubble-scale homogeneity.

James P. Zibin

2011-12-13T23:59:59.000Z

264

Mode-locked solid state lasers using diode laser excitation  

DOE Patents [OSTI]

A mode-locked laser employs a coupled-polarization scheme for efficient longitudinal pumping by reshaped laser diode bars. One or more dielectric polarizers are configured to reflect a pumping wavelength having a first polarization and to reflect a lasing wavelength having a second polarization. An asymmetric cavity provides relatively large beam spot sizes in gain medium to permit efficient coupling to a volume pumped by a laser diode bar. The cavity can include a collimation region with a controlled beam spot size for insertion of a saturable absorber and dispersion components. Beam spot size is selected to provide stable mode locking based on Kerr lensing. Pulse durations of less than 100 fs can be achieved in Yb:KGW.

Holtom, Gary R. (Boston, MA)

2012-03-06T23:59:59.000Z

265

The whistler mode refractive index as a function of gyrofrequency  

SciTech Connect (OSTI)

The refractive index for a constant-frequency whistler mode wave in an electron-proton plasma is considered as a function of position, through the local gyrofrequencies {Omega}{sub e,i}. The full cold plasma dispersion relation is used. The wave frequency can take any value up to the smaller of {Omega}{sub e} and the plasma frequency {omega}{sub pe}, but {omega}{sub pe} is allowed to take any fixed value, as is the wavenormal angle. It is rigorously established that the refractive index is a decreasing function of {Omega}{sub e}. One application of this is to finding locations of Landau and cyclotron resonances, to evaluate the effects of whistler mode waves on radiation belt electrons.

Albert, J. M. [Air Force Research Laboratory/RVBX, Kirtland AFB, New Mexico 87117 (United States)

2011-08-15T23:59:59.000Z

266

Present and Future Modes of Low Frequency Climate Variability  

SciTech Connect (OSTI)

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

Cane, Mark A.

2014-02-20T23:59:59.000Z

267

EFFECTS OF ASYMMETRIC FLOWS IN SOLAR CONVECTION ON OSCILLATION MODES  

SciTech Connect (OSTI)

Many helioseismic measurements suffer from substantial systematic errors. A particularly frustrating one is that time-distance measurements suffer from a large center to limb effect which looks very similar to the finite light travel time, except that the magnitude depends on the observable used and can have the opposite sign. This has frustrated attempts to determine the deep meridional flow in the solar convection zone, with Zhao et al. applying an ad hoc correction with little physical basis to correct the data. In this Letter, we propose that part of this effect can be explained by the highly asymmetrical nature of the solar granulation which results in what appears to the oscillation modes as a net radial flow, thereby imparting a phase shift on the modes as a function of observing height and thus heliocentric angle.

Baldner, Charles S.; Schou, Jesper, E-mail: baldner@stanford.edu [W.W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States)

2012-11-20T23:59:59.000Z

268

Development of magnetohydrodynamic modes during sawteeth in tokamak plasmas  

SciTech Connect (OSTI)

A dynamical analysis applied to a reduced resistive magnetohydrodynamics model is shown to explain the chronology of the nonlinear destabilization of modes observed in tokamak sawteeth. A special emphasis is put on the nonlinear self-consistent perturbation of the axisymmetric m = n = 0 mode that manifests through the q-profile evolution. For the very low fusion-relevant resistivity values, the q-profile is shown to remain almost unchanged on the early nonlinear timescale within the central tokamak region, which supports a partial reconnection scenario. Within the resistive region, indications for a local flattening or even a local reversed-shear of the q-profile are given. The impact of this ingredient in the occurrence of the sawtooth crash is discussed.

Firpo, M.-C.; Ettoumi, W. [Laboratoire de Physique des Plasmas, CNRS-Ecole Polytechnique, 91128 Palaiseau cedex (France)] [Laboratoire de Physique des Plasmas, CNRS-Ecole Polytechnique, 91128 Palaiseau cedex (France); Farengo, R. [Centro Atmico Bariloche (CNEA) and Instituto Balseiro (UNC-CNEA), San Carlos de Bariloche, RN 8400 (Argentina)] [Centro Atmico Bariloche (CNEA) and Instituto Balseiro (UNC-CNEA), San Carlos de Bariloche, RN 8400 (Argentina); Ferrari, H. E. [Centro Atmico Bariloche (CNEA) and Instituto Balseiro (UNC-CNEA), San Carlos de Bariloche, RN 8400 (Argentina) [Centro Atmico Bariloche (CNEA) and Instituto Balseiro (UNC-CNEA), San Carlos de Bariloche, RN 8400 (Argentina); Consejo Nacional de Investigaciones Cientficas y Tcnicas (CONICET), Bariloche (Argentina); Garca-Martnez, P. L. [Consejo Nacional de Investigaciones Cientficas y Tcnicas (CONICET), Bariloche (Argentina)] [Consejo Nacional de Investigaciones Cientficas y Tcnicas (CONICET), Bariloche (Argentina); Lifschitz, A. F. [Laboratoire d'Optique Applique, ENSTA, CNRS, Ecole Polytechnique, 91761 Palaiseau (France)] [Laboratoire d'Optique Applique, ENSTA, CNRS, Ecole Polytechnique, 91761 Palaiseau (France)

2013-07-15T23:59:59.000Z

269

Whistler Modes with Wave Magnetic Fields Exceeding the Ambient Field  

Science Journals Connector (OSTI)

Whistler-mode wave packets with fields exceeding the ambient dc magnetic field have been excited in a large, high electron-beta plasma. The waves are induced with a loop antenna with dipole moment either along or opposite to the dc field. In the latter case the excited wave packets have the topology of a spheromak but are propagating in the whistler mode along and opposite to the dc magnetic field. Field-reversed configurations with net zero helicity have also been produced. The electron magnetohydrodynamics fields are force free, have wave energy density exceeding the particle energy density, and propagate stably at subelectron thermal velocities through a nearly uniform stationary ion density background.

R. L. Stenzel; J. M. Urrutia; K. D. Strohmaier

2006-03-10T23:59:59.000Z

270

Growth mode evolution of hafnium oxide by atomic layer deposition  

SciTech Connect (OSTI)

HfO{sub 2} thin films were deposited using tetrakis-ethylmethylamido hafnium and H{sub 2}O as precursors on silicon by atomic layer deposition (ALD). The morphology and microstructures at different ALD cycles were characterized by atomic force microscopy and high-resolution transmission electron microscopy. Based on the heightheight correlation function and power spectral density function, quantitative analysis of surface morphologies was performed. Three characteristic dimensions (?{sub 1}, ?{sub 2}, and ?{sub 3}) corresponding to three surface structures, islands, local and global fluctuations, were identified. The evolution of ALD growth mode at range of the three critical scales was investigated, respectively. It suggests the transformation of growth mode from quasi two-dimensional layer-by-layer to three-dimensional island for global fluctuations.

Nie, Xianglong; Ma, Fei; Ma, Dayan, E-mail: madayan@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, Shaanxi (China); Xu, Kewei [State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, People's Republic of China and Department of Physics and Opt-electronic Engineering, Xi'an University of Arts and Science, Xi'an 710065, Shaanxi (China)

2014-01-15T23:59:59.000Z

271

Twisted Electromagnetic Modes and Sagnac Ring-Lasers  

E-Print Network [OSTI]

A new approximation scheme, designed to solve the covariant Maxwell equations inside a rotating hollow slender conducting cavity (modelling a ring-laser), is constructed. It is shown that for well-defined conditions there exist TE and TM modes with respect to the longitudinal axis of the cavity. A twisted mode spectrum is found to depend on the integrated Frenet torsion of the cavity and this in turn may affect the Sagnac beat frequency induced by a non-zero rotation of the cavity. The analysis is motivated by attempts to use ring-lasers to measure terrestrial gravito-magnetism or the Lense-Thirring effect produced by the rotation of the Earth.

David A. Burton; Adam Noble; Robin W. Tucker; David L. Wiltshire

2004-11-08T23:59:59.000Z

272

Optoelectronic cooling of mechanical modes in a semiconductor nanomembrane  

E-Print Network [OSTI]

Optical cavity cooling of mechanical resonators has recently become a research frontier. The cooling has been realized with a metal-coated silicon microlever via photo-thermal force and subsequently with dielectric objects via radiation pressure. Here we report cavity cooling with a crystalline semiconductor membrane via a new mechanism, in which the cooling force arises from the interaction between the photo-induced electron-hole pairs and the mechanical modes through the deformation potential coupling. The optoelectronic mechanism is so efficient as to cool a mode down to 4 K from room temperature with just 50 uW of light and a cavity with a finesse of 10 consisting of a standard mirror and the sub-wavelength-thick semiconductor membrane itself. The laser-cooled narrow-band phonon bath realized with semiconductor mechanical resonators may open up a new avenue for photonics and spintronics devices.

K. Usami; A. Naesby; T. Bagci; B. Melholt Nielsen; J. Liu; S. Stobbe; P. Lodahl; E. S. Polzik

2010-11-22T23:59:59.000Z

273

A new low-frequency backward mode in inhomogeneous plasmas  

SciTech Connect (OSTI)

When an electromagnetic transverse wave propagates through an inhomogeneous plasma so that its electric field has a component in the direction of the background density gradient, there appears a disbalance of charge in every plasma layer, caused by the density gradient. Due to this, some additional longitudinal electric field component appears in the direction of the wave vector. This longitudinal field may couple with the usual electrostatic longitudinal perturbations like the ion acoustic, electron Langmuir, and ion plasma waves. As a result, these standard electrostatic waves are modified and in addition to this a completely new low-frequency mode appears. Some basic features of the coupling and modification of the ion acoustic wave, and properties of the new mode are discussed here, in ordinary electron-ion and in pair plasmas.

Vranjes, J., E-mail: jvranjes@yahoo.com [Institute of Physics, Pregrevica 118, 11080 Zemun, Belgrade (Serbia)

2014-07-15T23:59:59.000Z

274

Engineering two-mode interactions in ion traps  

E-Print Network [OSTI]

We describe how two vibrational degrees of freedom of a single trapped ion can be coupled through the action of suitably-chosen laser excitation. We concentrate on a two-dimensional ion trap with dissimilar vibrational frequencies in the x- and y-directions of motion, and derive from first principles a variety of quantized two-mode couplings, concentrating on a linear coupling which takes excitations from one mode to another. We demonstrate how this can result in a state rotation, in which it is possible to transfer the motional state of the ion from say the x-direction to the y-direction without prior knowledge of that motional state.

J. Steinbach; J. Twamley; P. L. Knight

1997-08-04T23:59:59.000Z

275

Electromechanical Mode Online Estimation using Regularized Robust RLS Methods  

SciTech Connect (OSTI)

This paper proposes a regularized robust recursive least square (R3LS) method for on-line estimation of power-system electromechanical modes based on synchronized phasor measurement unit (PMU) data. The proposed method utilizes an autoregressive moving average exogenous (ARMAX) model to account for typical measurement data, which includes low-level pseudo-random probing, ambient, and ringdown data.? A robust objective function is utilized to reduce the negative influence from non-typical data, which include outliers and missing data. A dynamic regularization method is introduced to help include a priori knowledge about the system and reduce the influence of under-determined problems. Based on a 17-machine simulation model, it is shown through the Monte-Carlo method that the proposed R3LS method can estimate and track electromechani-cal modes by effectively using combined typical and non-typical measurement data.

Zhou, Ning; Trudnowski, Daniel; Pierre, John W.; Mittelstadt, William

2008-11-01T23:59:59.000Z

276

Constant residual electrostatic electron plasma mode in Vlasov-Ampere system  

SciTech Connect (OSTI)

In a collisionless Vlasov-Poisson (V-P) electron plasma system, two types of modes for electric field perturbation exist: the exponentially Landau damped electron plasma waves and the initial-value sensitive ballistic modes. Here, the V-P system is modified slightly to a Vlasov-Ampere (V-A) system. A new constant residual mode is revealed. Mathematically, this mode comes from the Laplace transform of an initial electric field perturbation, and physically represents that an initial perturbation (e.g., external electric field perturbation) would not be damped away. Thus, this residual mode is more difficult to be damped than the ballistic mode.

Xie, Hua-sheng [Institute for Fusion Theory and Simulation, Department of Physics, Zhejiang University, Hangzhou 310027 (China)] [Institute for Fusion Theory and Simulation, Department of Physics, Zhejiang University, Hangzhou 310027 (China)

2013-11-15T23:59:59.000Z

277

Modes in a pulse-modulated radio-frequency dielectric-barrier glow discharge  

SciTech Connect (OSTI)

This letter reports an experimental study of a pulse-modulated radio-frequency dielectric-barrier discharge in atmospheric helium. By controlling the duty cycle at a modulation frequency of 10 and 100 kHz, the 13.56 MHz discharge is shown to operate in three different glow modes: the continuum mode, the discrete mode, and the transition mode. By investigating plasma ignition, residual electrons during power off are found to affect different glow modes. Duty cycle dependences of power density, gas temperature, optical emission intensities at 706 and 777 nm are used to capture clearly the characteristics of the three glow modes.

Shi, J. J.; Zhang, J.; Qiu, G. [College of Science, Donghua University, Shanghai 201620 (China); Walsh, J. L.; Kong, M. G. [Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom)

2008-07-28T23:59:59.000Z

278

Modes in a pulse-modulated radio-frequency dielectric-barrier glow discharge  

Science Journals Connector (OSTI)

This letter reports an experimental study of a pulse-modulated radio-frequency dielectric-barrier discharge in atmospheric helium. By controlling the duty cycle at a modulation frequency of 10 and 100 kHz the 13.56 MHz discharge is shown to operate in three different glow modes: the continuum mode the discrete mode and the transition mode. By investigating plasma ignition residual electrons during power off are found to affect different glow modes. Duty cycle dependences of power density gas temperature optical emission intensities at 706 and 777 nm are used to capture clearly the characteristics of the three glow modes.

J. J. Shi; J. Zhang; G. Qiu; J. L. Walsh; M. G. Kong

2008-01-01T23:59:59.000Z

279

Theory of semicollisional drift-interchange modes in cylindrical plasmas  

SciTech Connect (OSTI)

Resistive interchange instabilities in cylindrical plasmas are studied, including the effects of electron diamagnetic drift, perpendicular resistivity, and plasma compression. The analyses are pertinent to the semicollisional regime where the effective ion gyro-radius is larger than the resistive layer width. Both analytical and numerical results show that the modes can be completely stabilized by the perpendicular plasma transport. Ion sound effects, meanwhile, are found to be negligible in the semicollisional regime.

Hahm, T.S.; Chen, L.

1985-01-01T23:59:59.000Z

280

Deterministic passive mode locking of solid-state lasers  

SciTech Connect (OSTI)

An additional passive modulation is inserted in the cavity of a passive mode-locked Nd:glass laser in order to provide the conditions for a complete selectivity of the system. A rate equation approach shows that a stationary condition is reached in which only one pulse of the original fluctuation pattern is left. Computed simulations and experimental results are also shown confirming the theoretical predictions.

Martinez, O.E.; Spinelli, L.A.

1981-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

Fact #602: December 21, 2009 Freight Statistics by Mode, 2007...  

Energy Savers [EERE]

Truck 70.7% 68.8% 39.8% Rail 3.3% 14.8% 37.1% Water 0.9% 3.3% 5.0% Air 1.8% 0.0% 0.1% Pipeline 4.1% 6.0% NA Parcel, USPS, or Courier 13.5% 0.3% 0.8% Multiple Modes 2.9% 4.5% 13.2%...

282

Photon detection efficiency of Geiger-mode avalanche photodiodes  

E-Print Network [OSTI]

The photon detection efficiencies of multi-pixel Geiger-mode avalanche photodiodes manufactured by different produ cers are estimated. A new fit method of the response spectra to low-intensity light, taking into ac count after-pulse and cross-talk effects is proposed to yield the initial number of photons. The value of photon detection efficiency is calculated using a calibrated photodetector as a reference.

Simonetta Gentile; Ekaterina Kuznetsova; Franco Meddi

2010-06-16T23:59:59.000Z

283

Composite slip table of dissimilar materials for damping longitudinal modes  

DOE Patents [OSTI]

A vibration slip table for use in a vibration testing apparatus. The table s comprised of at least three composite layers of material; a first metal layer, a second damping layer, and a third layer having a high acoustic velocity relative to the first layer. The different acoustic velocities between the first and third layers cause relative shear displacements between the layers with the second layer damping the displacements between the first and third layers to reduce the table longitudinal vibration modes.

Gregory, Danny L. (Albuquerque, NM); Priddy, Tommy G. (Albuquerque, NM); Smallwood, David O. (Albuquerque, NM); Woodall, Tommy D. (Albuquerque, NM)

1991-01-01T23:59:59.000Z

284

Gravitational-wave modes from precessing black-hole binaries  

E-Print Network [OSTI]

Gravitational waves from precessing black-hole binaries exhibit features that are absent in nonprecessing systems. The most prominent of these is a parity-violating asymmetry that beams energy and linear momentum preferentially along or opposite to the orbital angular momentum, leading to recoil of the binary. The asymmetry will appear as amplitude and phase modulations at the orbital frequency. For strongly precessing systems, it accounts for at least 3% amplitude modulation for binaries in the sensitivity band of ground-based gravitational-wave detectors, and can exceed 50% for massive systems. Such asymmetric features are also clearly visible when the waves are decomposed into modes of spin-weighted spherical harmonics, and are inherent in the waves themselves---rather than resulting from residual eccentricity in numerical simulations, or from mode-mixing due to precession. In particular, there is generically no instantaneous frame for which the mode decomposition will have any symmetry. We introduce a method to simplify the expressions for waveforms given in analytical relativity, which can be used to combine existing high-order waveforms for nonprecessing systems with expressions for the precessing contributions, leading to improved accuracy and a unified treatment of precessing and nonprecessing binaries. Using this method, it is possible to clarify the nature and the origins of the asymmetries and show the effects of asymmetry on recoils more clearly. We present post-Newtonian (PN) expressions for the waveform modes that include these terms, complete to the relative 2PN level in spin (proportional to $v^4/c^4$ times a certain combination of the spins). Comparing the results of those expressions to numerical results, we find good qualitative agreement. We also demonstrate how these expressions can be used to efficiently calculate waveforms for gravitational-wave astronomy.

Michael Boyle; Lawrence E. Kidder; Serguei Ossokine; Harald P. Pfeiffer

2014-09-15T23:59:59.000Z

285

Resistive edge mode instability in stellarator and tokamak geometries  

SciTech Connect (OSTI)

Geometrical effects on linear stability of electrostatic resistive edge modes are investigated in the three-dimensional Wendelstein 7-X stellarator [G. Grieger et al., Plasma Physics and Controlled Nuclear Fusion Research 1990 (International Atomic Energy Agency, Vienna, 1991), Vol. 3, p. 525] and the International Thermonuclear Experimental Reactor [Progress in the ITER Physics Basis, Nucl. Fusion 7, S1, S285 (2007)]-like equilibria. An advanced fluid model is used for the ions together with the reduced Braghinskii equations for the electrons. Using the ballooning mode representation, the drift wave problem is set as an eigenvalue equation along a field line and is solved numerically using a standard shooting technique. A significantly larger magnetic shear and a less unfavorable normal curvature in the tokamak equilibrium are found to give a stronger finite-Larmor radius stabilization and a more narrow mode spectrum than in the stellarator. The effect of negative global magnetic shear in the tokamak is found to be stabilizing. The growth rate on a tokamak magnetic flux surface is found to be comparable to that on a stellarator surface with the same global magnetic shear but the eigenfunction in the tokamak is broader than in the stellarator due to the presence of large negative local magnetic shear (LMS) on the tokamak surface. A large absolute value of the LMS in a region of unfavorable normal curvature is found to be stabilizing in the stellarator, while in the tokamak case, negative LMS is found to be stabilizing and positive LMS destabilizing.

Mahmood, M. Ansar; Rafiq, T.; Persson, M.; Weiland, J. [Department of Signals and Systems, Chalmers University of Technology and Euratom-VR Association, S-41296 Goeteborg (Sweden)

2008-09-15T23:59:59.000Z

286

CMR Shuffler System: Passive Mode Calibration and Certification Report  

SciTech Connect (OSTI)

Los Alamos National Laboratory has a number of spherical confinement vessels (CVs) remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1 to 2 inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. As debris is removed from the vessels, material will be placed in waste drums. Far-field gamma ray assay will be used to determine when a drum is nearing a {sup 239}Pu equivalent mass of less than 200 g. The drum will then be assayed using a waste drum shuffler operated in passive mode using a neutron coincidence counting method for accountability. This report focuses on the testing and calibration of the CMR waste drum shuffler in passive mode operation. Initial testing was performed to confirm previously accepted measurement parameters. The system was then calibrated using a set of weapons grade Pu (WGPu, {sup 239}Pu > 93%) oxide standards placed inside a 55 gallon drum. The calibration data ranges from Pu mass of 0.5 g to 188.9 g. The CMR waste drum shuffler has been tested and calibrated in passive mode in preparation for safeguards accountability measurements of waste drums containing material removed from CVs for the CVD project.

Frame, Katherine C. [Los Alamos National Laboratory; Gomez, Cipriano D. [Retired CMR-OPS: OPERATIONS; Salazar, William R. [Los Alamos National Laboratory; Mayo, Douglas R. [Los Alamos National Laboratory; Vigil, Georgiana M. [Los Alamos National Laboratory; Crooks, William J. [Los Alamos National Laboratory; Stange, Sy [Los Alamos National Laboratory

2012-07-20T23:59:59.000Z

287

Energetic/alpha particle effects on MHD modes and transport  

SciTech Connect (OSTI)

A nonvariational kinetic-MHD stability code (NOVA-K) has been employed to study TAE stability in TFRR D-T and DIII-D experiments and to achieve understanding of TAE instability drive and damping mechanism. Reasonably good agreement between theory and experiment has been obtained. In these experiments the dominant damping mechanism is due to both the thermal ion Landau damping and/or the beam ion Landau damping. Based on ITER EDA parameters, the TAE modes are expected to be unstable in normal ITER operations. Energetic particle transport has been studied using a test particle code (ORBIT). Energetic particle loss scales linearly with the TAE mode amplitude and can be large for TFRR and DIII-D for {delta}B{sub r}/B > 10{sup {minus}4} due to large banana orbit. From quasi-linear (ORBIT) and nonlinear kinetic-MHD (MH3D-K) simulations the saturation of TAE modes is due to nonlinear wave particle trapping and energetic particle profile modification in both radial and energy space. Finally, a convective bucket transport mechanism by MHD waves with time-dependent frequency is presented. Based on the energy-selective characteristics of the bucket transport mechanism, undesirable particles such as helium ash can be removed from the plasma core efficiently.

Cheng, C.Z.; Budny, R. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Chen, L. [Univ. of California, Irvine, CA (United States). Dept. of Physics

1995-01-01T23:59:59.000Z

288

Anisotropic Alfven-ballooning modes in the Earth's magnetosphere  

SciTech Connect (OSTI)

We have carried out a theoretical analysis of the stability and parallel structure of coupled shear-Alfven and slow-magnetosonic waves in the Earth's inner magnetosphere including effects of finite anisotropic plasma pressure. Multiscale perturbation analysis of the anisotropic Grad-Shafranov equation yields an approximate self-consistent magnetohydrodynamic (MHD) equilibrium. This MHD equilibrium is used in the numerical solution of a set of eigenmode equations which describe the field line eigenfrequency, linear stability, and parallel eigenmode structure. We call these modes anisotropic Alfven-ballooning modes. The main results are: The field line eigenfrequency can be significantly lowered by finite pressure effects. The parallel mode structure of the transverse wave components is fairly insensitive to changes in the plasma pressure but the compressional magnetic component can become highly peaked near the magnetic equator due to increased pressure, especially when P[perpendicular] > P[parallel]. For the isotropic case ballooning instability can occur when the ratio of the plasma pressure to the magnetic pressure, exceeds a critical value [beta][sub o][sup B] [approx] 3.5 at the equator. Compared to the isotropic case the critical beta value is lowered by anisotropy, either due to decreased field-line-bending stabilization when P[parallel] > P[perpendicular], or due to increased ballooning-mirror destabilization when P[perpendicular] > P[parallel]. We use a [beta]-6 stability diagram'' to display the regions of instability with respect to the equatorial values of the parameters [bar [beta

Chan, A.A. (Dartmouth Coll., Hanover, NH (United States). Dept. of Physics and Astronomy); Xia, Mengfen (Beijing Univ., BJ (China). Dept. of Physics); Chen, Liu (Princeton Univ., NJ (United States). Plasma Physics Lab.)

1993-05-01T23:59:59.000Z

289

Prufer Transformations for the Normal Modes in Ocean Acoustics  

SciTech Connect (OSTI)

In 1926 Prufer introduced a method of transforming the second order Sturm-Liouville (SL) equation into two nonlinear first order differential equations for the phase oe and ''magnitude'', |oe{sup 2}+oe{sup 2}| for a Poincare phase space representation, (oe,oe). The useful property is the phase equation decouples from the magnitude one which leads to a nonlinear, two point boundary value problem for the eigenvalues, or SL numbers. The transformation has been used both theoretically, e.g. Atkinson, [1960] to prove certain properties of SL equations as well as numerically e.g Bailey [1978]. This paper examines the utility of the Prufer transformation in the context of numerical solutions for modes of the ocean acoustic wave equation. (Its use is certainly not well known in the ocean acoustics community.) Equations for the phase, oe, and natural logarithm of the ''magnitude'', ln(|oe{sup 2}+oe{sup 2}|) lead to same decoupling and a fast and efficient numerical solution with the SL eigenvalues mapping to the horizontal wavenubers. The Prufer transformation has stabilty problems for low order modes at high frequecies, so a numerically stable method of integrating the phase equation is derived. This seems to be the first time the these stability issues have been highlighted to provide a robust algorthim for the modes.

Baggeroer, Arthur B. [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

2010-09-06T23:59:59.000Z

290

MIT's Plasma Science Fusion Center: I-Mode Powers Up on Alcator...  

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

I-Mode Powers Up on Alcator C-Mod Tokamak American Fusion News Category: Massachusetts Institute of Technology (MIT) Link: MIT's Plasma Science Fusion Center: I-Mode Powers Up on...

291

Study of H-mode access conditions on the Alcator C-Mod Tokamak  

E-Print Network [OSTI]

Usually when sufficient heating power is injected, tokamak plasma will make an abrupt transition into a state with improved confinement, known as the high-confinement mode, or H-mode. Given the greatly enhanced fusion ...

Ma, Yunxing

2013-01-01T23:59:59.000Z

292

E-Print Network 3.0 - ac mode comparative Sample Search Results  

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

Summary: mode analyses for Mercier stable and*E-mail: nakajima@nifs.ac.jp FUSION SCIENCE AND TECHNOLOGY VOL. 51... by comparing the eigenvalues obtained by global mode...

293

Modeling streamers in transformer oil: The transitional fast 3rd mode streamer  

E-Print Network [OSTI]

This paper presents an electro-thermal hydrodynamic model that explains the development of different streamer modes in transformer oil. The focus is on the difference between the slow 2nd and fast 3rd mode streamers ...

Zahn, Markus

294

Bifurcation of the f -mode in presence of non-uniform magnetic field  

E-Print Network [OSTI]

of the f- mode in standard k! diagram in our sim- ulations where the magnetic field is mostly concentrated beneath the interface. 1 Summary Earlier work by Berton & Heyvaerts (1987) on MHD modes

Brandenburg, Axel

295

Northwest Energy Innovations (TRL 5 6 System) - WETNZ MtiMode...  

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

Northwest Energy Innovations (TRL 5 6 System) - WETNZ MtiMode Wave Energy Converter Advancement Project Northwest Energy Innovations (TRL 5 6 System) - WETNZ MtiMode Wave Energy...

296

Optimization of NH3 Decomposition by Control of Discharge Mode in a Rotating Arc  

Science Journals Connector (OSTI)

In this study, the characteristic behavior of a rotating arc was investigated. Various modes, depending on the electric power supplied, can be observed in a rotating arc. Each mode produces different discharge ch...

Dae Hoon Lee; Kwan-Tae Kim; Hee Seok Kang

2014-01-01T23:59:59.000Z

297

Failure mode and effects analysis using intuitionistic fuzzy hybrid TOPSIS approach  

Science Journals Connector (OSTI)

Failure mode and effects analysis (FMEA) is an effective reliability analysis technique used ... , processes, and/or designs. In traditional FMEA, prioritization of failure modes is carried out ... the risk prior...

Hu-Chen Liu; Jian-Xin You; Meng-Meng Shan; Lu-Ning Shao

2014-06-01T23:59:59.000Z

298

E-Print Network 3.0 - adaptive sliding mode Sample Search Results  

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

Sweden (KTH) Collection: Engineering 83 High-Order Sliding Mode Control of a DFIG-Based Wind Turbine Summary: High-Order Sliding Mode Control of a DFIG-Based Wind...

299

Eigenvalue Analysis of a DFIG Based Wind Power System under Different Modes of Operations  

Science Journals Connector (OSTI)

This chapter discussed the various mode of operation of the Doubly Fed Induction Generator (DFIG) based wind farm system. The impact ... on the different modes of operation for the DFIG based wind generation syst...

Y. Mishra; S. Mishra; Fangxing Li; Z. Y. Dong

2010-01-01T23:59:59.000Z

300

Current mode integrators and their applications in low-voltage high frequency CMOS signal processing  

E-Print Network [OSTI]

Low voltage CMOS fully differential integrators for high frequency continuous-time filters using current-mode techniques are presented.. Current mode techniques are employed to avoid the use of the floating differential pair, in order to achieve...

Smith, Sterling Lane

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

High power, 60MHz, cryogenically cooled, mode-locked, Yb:YAG oscillator  

Science Journals Connector (OSTI)

We demonstrate a 60MHz, cryogenically cooled, mode-locked Yb:YAG oscillator with up to 12W average output power. Mode-locking is achieved via a SESAM, an intracavity SHG crystal, and...

Gerrity, Michael; Brown, Susannah; Popmintchev, Tenio; Chen, Ming-Chang; Witte, Stefan; Murnane, Margaret M; Kapteyn, Henry C; Backus, Sterling

302

Mode propagation and absorption loss in metal-clad periodic optical waveguides  

SciTech Connect (OSTI)

In terms of the mode eigenvalue equations are field distributions, calculations are performed for Au/InGaAsP/InP, air/Au/InGaAsP/InP, and Au/DiO{sub 2}InGaAsP/InP periodic optical waveguides. On the basis of the computed results, the coupling property in the periodic structure is analyzed, the mode split and the mode band formation of both TE and TM guided modes are described, and the effects of the thickness of the metal cladding and the oxide buffer layer on mode propagation and absorption loss are discussed for TE and TM guided modes as well as for the TM surface-plasma mode. Furthermore, the conversion from the surface-plasma wave to the guided wave for the TM mode is explained for Au/SiO{sub 2}/InGaAsP/InP periodic structures. 27 refs., 8 figs.

Chunsheng Ma [Jilin Univ., Changchun (China)

1996-02-01T23:59:59.000Z

303

A Scheme to Retain the Hadley Circulation During Nonlinear Normal Mode Initialization  

Science Journals Connector (OSTI)

A modified nonlinear normal mode initialization scheme is proposed which provides a possible solution to a major problem associated with nonlinear normal mode initialization. The modified scheme retains the Hadley circulation in the model and at ...

K. Puri; W. Bourke

1982-05-01T23:59:59.000Z

304

Destabilization of low-n peeling modes by trapped energetic particles  

SciTech Connect (OSTI)

The kinetic effect of trapped energetic particles (EPs), arising from perpendicular neutral beam injection, on the stable low-n peeling modes in tokamak plasmas is investigated, through numerical solution of the mode's dispersion relation derived from an energy principle. A resistive-wall peeling mode with m/n=6/1, with m and n being the poloidal and toroidal mode numbers, respectively, is destabilized by trapped EPs as the EPs' pressure exceeds a critical value ?{sub c}{sup *}, which is sensitive to the pitch angle of trapped EPs. The dependence of ?{sub c}{sup *} on the particle pitch angle is eventually determined by the bounce average of the mode eigenfunction. Peeling modes with higher m and n numbers can also be destabilized by trapped EPs. Depending on the wall distance, either a resistive-wall peeling mode or an ideal-kink peeling mode can be destabilized by EPs.

Hao, G. Z.; Wang, A. K.; Mou, Z. Z.; Qiu, X. M. [Southwestern Institute of Physics, PO Box 432, Chengdu 610041 (China)] [Southwestern Institute of Physics, PO Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Matsunaga, G. [Japan Atomic Energy Agency, 801-1, Mukouyama, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, 801-1, Mukouyama, Naka, Ibaraki 311-0193 (Japan); Okabayashi, M. [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543-0451 (United States)] [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543-0451 (United States)

2013-06-15T23:59:59.000Z

305

Time-varying effects and averaging issues in models for current-mode control  

E-Print Network [OSTI]

This paper investigates issues in modeling of current-mode control in converters. The effects of the current-sampling intrinsic to current-mode control are analyzed, and inadequately recognized limitations of linear ...

Perreault, David J.

306

ECG ARTIFACT REMOVAL FROM SURFACE EMG SIGNALS BY COMBINING EMPIRICAL MODE DECOMPOSITION AND  

E-Print Network [OSTI]

ECG ARTIFACT REMOVAL FROM SURFACE EMG SIGNALS BY COMBINING EMPIRICAL MODE DECOMPOSITION separation, ensemble empirical mode decomposition, ECG interference artifact, data preprocessing Abstract: The electrocardiography (ECG) artifact in surface electromyography (sEMG) is a major source of noise influencing

307

Behavior of reflected extraordinary mode in the fundamental electron cyclotron heating and current drive in JT-60U  

Science Journals Connector (OSTI)

Unwanted X-mode behavior in the fundamental harmonic electron cyclotron (EC) wave launching from the low field side with an oblique toroidal injection angle is experimentally studied on JT-60U by changing the poloidal injection angle. It is found that there is a critical region in the poloidal injection angle to cause the rise in vacuum pressure at the NBI port adjacent to the ECRF antenna port. The typical EC beam power is about 1 MW and the pulse length is 3 s in this experiment. The ray-trace calculation indicates that the X-mode launched from the low field side is guided into the NBI port after reflection at the cut-off layer for the critical poloidal injection angle. The results suggest that the O-mode injection with quite high mode purity, that is, with a very low fraction of X-mode is required for the avoidance of the overheat of the in-vessel components due to the reflected X-mode in the case of the EC beam launching from the low field side, especially for long pulse operation.

K. Kajiwara; S. Moriyama; K. Takahashi; Y. Ikeda; M. Seki; T. Fujii

2003-01-01T23:59:59.000Z

308

Entanglement of nanomechanical oscillators and two-mode fields induced by atomic coherence  

SciTech Connect (OSTI)

We propose a scheme for three-level cascade atoms to entangle two optomechanical oscillators as well as two-mode fields. We show that two movable mirrors and two-mode fields can be entangled even for bad cavity limits. We also study entanglement of the output of two-mode fields in the frequency domain. The results show that the frequency of the mirror oscillation and the injected atomic coherence affect the output entanglement of the two-mode fields.

Zhou Ling; Han Yan [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Jing Jietai; Zhang Weiping [State Key Laboratory of Precision Spectroscopy, Department of Physics, East China Normal University, Shanghai 200062 (China)

2011-05-15T23:59:59.000Z

309

Intense Geodesic Acousticlike Modes Driven by Suprathermal Ions in a Tokamak Plasma R. Nazikian,1  

E-Print Network [OSTI]

Intense Geodesic Acousticlike Modes Driven by Suprathermal Ions in a Tokamak Plasma R. Nazikian,1 G for the energetic-particle-driven geodesic acoustic mode. DOI: 10.1103/PhysRevLett.101.185001 PACS numbers: 52.35.Bj of strong beam ion redistribution and/or loss. The mode fre- quency is $50% below the ideal geodesic

310

Kinetic Theories of Geodesic Acoustic Modes: Radial Structure, Linear Excitation by Energetic Particles and Nonlinear Saturation  

E-Print Network [OSTI]

Kinetic Theories of Geodesic Acoustic Modes: Radial Structure, Linear Excitation by Energetic, Vol.13, No.3, Jun 2011 Kinetic Theories of Geodesic Acoustic Modes: Radial Structure, Linear, Univ. of California, Irvine CA 92697-4575, USA Abstract Geodesic acoustic modes (GAMs) are oscillating

Zonca, Fulvio

311

Kinetic theory of Geodesic Acoustic Modes: radial structures and nonlinear excitations  

E-Print Network [OSTI]

1 TH/P3-7 Kinetic theory of Geodesic Acoustic Modes: radial structures and nonlinear excitations F author: zonca@frascati.enea.it Abstract. Geodesic Acoustic Modes (GAM) are shown to constitute, we show that Geodesic Acoustic Modes (GAM) [1] constitute a continuous spec- trum due to radial

Zonca, Fulvio

312

An Attack on CFB Mode Encryption As Used By OpenPGP Serge Mister & Robert Zuccherato  

E-Print Network [OSTI]

An Attack on CFB Mode Encryption As Used By OpenPGP Serge Mister & Robert Zuccherato Entrust, Inc.mister,robert.zuccherato}@entrust.com Abstract. This paper describes an adaptive-chosen-ciphertext attack on the Cipher Feedback (CFB) mode for each block. Standard CFB mode encryption does not appear to be affected by this attack. It applies

313

Symmetric Encryption. Part 2Symmetric Encryption. Part 2 Block ciphers modes  

E-Print Network [OSTI]

) · Cipher Block Chaining (CBC) · Cipher Feedback Mode (CFB) COMP 522 Electronic Codebook Mode (ECB) · Simple (CFB) · CFB mode may be used to transform a block cipher to the stream cipher; · It has a parameter ss it is 64 bits); · Again, an initialisation vector is needed. COMP 522 s-bits CFB encryption COMP 522 s

Fisher, Michael

314

Bifurcation of the f-mode in presence of non-uniform magnetic field  

E-Print Network [OSTI]

of the bifurcation and plausibly a continuous spectrum of the f- mode in standard k diagram in our sim- ulations & Heyvaerts (1987) on MHD modes in a periodic magnetic field, but not the f-mode. Effect of surface ten- sion

Brandenburg, Axel

315

Ontology-Based Reuse of Failure Modes for FMEA: Methodology and Tool  

Science Journals Connector (OSTI)

The wide application of FMEA in reliability engineering is generally appreciated, and how to identify the failure modes is the key to it. Failure modes, however, rely only on specific components rather than the system architecture, and therefore could ... Keywords: FMEA, ontology, failure modes

Guoqi Li

2012-11-01T23:59:59.000Z

316

Signal-to-noise ratio of Geiger-mode avalanche photodiode single-photon  

E-Print Network [OSTI]

Signal-to-noise ratio of Geiger-mode avalanche photodiode single-photon counting detectors Kimberly Kolb #12;Signal-to-noise ratio of Geiger-mode avalanche photodiode single-photon counting detectors, Rochester, New York 14623 Abstract. Geiger-mode avalanche photodiodes (GM-APDs) use the avalanche mechanism

Figer, Donald F.

317

Elephant modes and low frequency unsteadiness in a high Reynolds number, transonic afterbody wake  

E-Print Network [OSTI]

Elephant modes and low frequency unsteadiness in a high Reynolds number, transonic afterbody wake: 129.104.29.1 On: Wed, 09 Jul 2014 11:28:59 #12;Elephant modes and low frequency unsteadiness in a high. This result strongly suggests that a so-called elephant mode is responsible for the intense oscillations

Paris-Sud XI, Université de

318

Mode-locked fiber lasers using vertically aligned carbon nanotubes directly synthesized onto substrates  

E-Print Network [OSTI]

Mode-locked fiber lasers using vertically aligned carbon nanotubes directly synthesized onto novel passively mode-locked fiber lasers using vertically aligned carbon nanotubes synthesized using.4890) Organic materials 1. Introduction Passively mode-locked fiber lasers have been used in many applications

Maruyama, Shigeo

319

Investigation of ELM [edge localized mode] Dynamics with the Resonant Magnetic Perturbation Effects  

SciTech Connect (OSTI)

Topics covered are: anomalous transport and E x B flow shear effects in the H-mode pedestal; RMP (resonant magnetic perturbation) effects in NSTX discharges; development of a scaling of H-mode pedestal in tokamak plasmas with type I ELMs (edge localized modes); and divertor heat load studies.

Pankin, Alexei Y.; Kritz, Arnold H.

2011-07-19T23:59:59.000Z

320

Mixed-mode fracture of human cortical bone Elizabeth A. Zimmermann a,b  

E-Print Network [OSTI]

Mixed-mode fracture of human cortical bone Elizabeth A. Zimmermann a,b , Maximilien E. Launey Available online 1 July 2009 Keywords: Human cortical bone Mixed-mode fracture Fracture toughness Fracture mechanisms a b s t r a c t Although the mode I (tensile opening) fracture toughness has been the focus

Ritchie, Robert

Note: This page contains sample records for the topic "modes mode fraction" 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

Search for invisible decays of Higgs bosons in the vector boson fusion and associated ZH production modes  

SciTech Connect (OSTI)

A search for invisible decays of Higgs bosons is performed using the vector boson fusion and associated ZH production modes. In the ZH mode, the Z boson is required to decay to a pair of charged leptons or a b b-bar quark pair. The searches use the 8 TeV pp collision dataset collected by the CMS detector at the LHC, corresponding to an integrated luminosity of up to 19.7 inverse femtobarns. Certain channels include data from 7 TeV collisions corresponding to an integrated luminosity of 4.9 inverse femtobarns. The searches are sensitive to non-standard-model invisible decays of the recently observed Higgs boson, as well as additional Higgs bosons with similar production modes and large invisible branching fractions. In all channels, the observed data are consistent with the expected standard model backgrounds. Limits are set on the production cross section times invisible branching fraction, as a function of the Higgs boson mass, for the vector boson fusion and ZH production modes. By combining all channels, and assuming standard model Higgs boson cross sections and acceptances, the observed (expected) upper limit on the invisible branching fraction at m[H] = 125 GeV is found to be 0.58 (0.44) at 95% confidence level. We interpret this limit in terms of a Higgs-portal model of dark matter interactions.

Chatrchyan, Serguei; et. al,

2014-08-01T23:59:59.000Z

322

Search for invisible decays of Higgs bosons in the vector boson fusion and associated ZH production modes  

E-Print Network [OSTI]

A search for invisible decays of Higgs bosons is performed using the vector boson fusion and associated ZH production modes. In the ZH mode, the Z boson is required to decay to a pair of charged leptons or a b b-bar quark pair. The searches use the 8 TeV pp collision dataset collected by the CMS detector at the LHC, corresponding to an integrated luminosity of up to 19.7 inverse femtobarns. Certain channels include data from 7 TeV collisions corresponding to an integrated luminosity of 4.9 inverse femtobarns. The searches are sensitive to non-standard-model invisible decays of the recently observed Higgs boson, as well as additional Higgs bosons with similar production modes and large invisible branching fractions. In all channels, the observed data are consistent with the expected standard model backgrounds. Limits are set on the production cross section times invisible branching fraction, as a function of the Higgs boson mass, for the vector boson fusion and ZH production modes. By combining all channels, and assuming standard model Higgs boson cross sections and acceptances, the observed (expected) upper limit on the invisible branching fraction at m[H] = 125 GeV is found to be 0.58 (0.44) at 95% confidence level. We interpret this limit in terms of a Higgs-portal model of dark matter interactions.

CMS Collaboration

2014-04-04T23:59:59.000Z

323

Nonlinear viscosity and its role in drift-Alfven modes  

SciTech Connect (OSTI)

The moment approach is used to analyze the part of the magnetized plasma viscosity related to the nonlinear character of the Landau collision integral in the Boltzmann kinetic equation (nonlinear viscosity), pointed out by Catto and Simakov [Phys. Plasmas 11, 90 (2004)]. It is shown that the results of these authors, who have used an alternative procedure based on a more detailed analysis of the kinetic equation, correspond to a 15-moment approach. In comparison with the 13-moment approach (density, temperature, velocity, heat flux, and the viscosity tensor) of Grad, the 15-moment approach takes into account two higher-order moments, one of which is the vector-type moment similar to the parallel heat flux and the second is the tensor-type moment similar to the parallel projection of the viscosity tensor. Both these higher-order moments enter into the Braginskii approximation. The nonlinear viscosity calculated in the scope of the 13-moment Grad approach is qualitatively the same as that found by Catto and Simakov. Its role is investigated for drift-Alfven modes, driven by the combined effect of the dissipative part of perpendicular heat conductivity and the standard collisional viscosity, and it is shown to be essential for the radial transport of these modes. It is shown that the wave packet of drift-Alfven modes, propagating in the diamagnetic drift direction and driven for reversed temperature gradient, is transported down the pressure gradient. In contrast to this, the wave packet propagating in the electron diamagnetic drift direction and driven for positive temperature gradient is transported up the pressure gradient.

Tsypin, V.S.; Mikhailovskii, A.B.; Shirokov, M.S.; Kovalishen, E.A.; Konovalov, S.V.; Galvao, R.M.O. [Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo (Brazil); Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation) and Nonlinear Physics Laboratory, Moscow Institute of Physics and Technology, Institutskii per. 9, Dolgoprudnyi 141700, Moscow Region (Russian Federation); Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation) and Moscow Engineering Physics Institute, Kashirskoe Shosse 31, Moscow 115409 (Russian Federation); Nonlinear Physics Laboratory, Moscow Institute of Physics and Technology, Institutskii per. 9, Dolgoprudnyi 141700 (Russian Federation) and Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation); Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation); Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo (Brazil) and Brazilian Center for Research in Physics, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil)

2005-12-15T23:59:59.000Z

324

Anisotropic Alfven-ballooning modes in Earth`s magnetosphere  

SciTech Connect (OSTI)

The authors have carried out a theoretical analysis of the stability and parallel structure of coupled shear Alfven and slow magnetosonic waves in Earth`s inner magnetosphere (i.e., at equatorial distances between about five and ten Earth radii) including effects of finite anisotropic plasma pressure. Multiscale perturbation analysis of the anisotropic Grad-Shafranov equation yields an approximate self-consistent magnetohydrodynamic (MHD) equilibrium. This MHD equilibrium is used in the numerical solution of a set of eigenmode equations which describe the field line eigenfrequency, linear stability, and parallel eigenmode structure. The authors call these modes anisotropic Alfven-ballooning modes. The main results are: (1) The field line eigenfrequency can be significantly lowered by finite pressure effects. (2) The parallel mode structure of the transverse wave components in fairly insensitive to changes in the plasma pressure, but the compressional magnetic component can become highly peaked near the magnetic equator as a result of increased pressure, especially when P{perpendicular}>P{parallel} (here P{perpendicular} and P{parallel} are the perpendicular and parallel plasma pressure). (3) For the isotropic (P{parallel}=P{perpendicular}=P) case ballooning instability can occur when the ratio of the plasma pressure to the magnetic pressure exceeds a critical value {beta}{sub 0}{sup B}{approx} 3.5 at the equator. (4) Compared to the isotropic case the critical beta value is lowered by anisotropy. (5) The authors use a {beta}-{delta} stability diagram to display the regions of instability with respect to the equatorial values of the parameters {beta} and {delta}, where {beta} = (1/3)({beta}{parallel}+2{beta}{perpendicular}) is an average beta value and {delta}=1-P{parallel}/P{perpendicular} is a measure of the plasma anisotropy. The diagram is divided into regions corresponding to the firehose, mirror and ballooning instabilities. 31 refs., 8 figs.

Chan, A.A. [Rice Univ., Houston, TX (United States)] [Rice Univ., Houston, TX (United States); Xia, M. [Peking Univ., Beijing (China)] [Peking Univ., Beijing (China); Chen, L. [Univ. of California, Irving, CA (United States)] [Univ. of California, Irving, CA (United States)

1994-09-01T23:59:59.000Z

325

Multi-parameter Laser Modes in Paraxial Optics  

E-Print Network [OSTI]

We study multi-parameter solutions of the inhomogeneous paraxial wave equation in a linear and quadratic approximation which include oscillating laser beams in a parabolic waveguide, spiral light beams, and other important families of propagation-invariant laser modes in weakly varying media. A similar effect of superfocusing of particle beams in a thin monocrystal film is also discussed. In the supplementary electronic material, we provide a computer algebra verification of the results presented here, and of some related mathematical tools that were stated without proofs in the literature.

Christoph Koutschan; Erwin Suazo; Sergei K. Suslov

2014-07-09T23:59:59.000Z

326

Quantum and classical separability of spin-orbit laser modes  

E-Print Network [OSTI]

In this work we investigate the quantum noise properties of polarization vortices in connection with an intensity based Clauser-Horne-Shimony-Holt inequality for their spin-orbit separability. We evaluate the inequality for different input quantum states and the corresponding intensity fluctuations. The roles played by coherence and photon number squeezing provide a suitable framework for characterizing pure state spin-orbit entanglement. Structural inseparability of the spin-orbit mode requires coherence, an issue concerning either classical or quantum descriptions. In both cases, it can be witnessed by violation of this intensity based CHSH inequality. However, in the quantum domain, entanglement requires both coherence and reduced photon number fluctuations.

L. J. Pereira; A. Z. Khoury; K. Dechoum

2014-09-02T23:59:59.000Z

327

Landau Damping of Geodesic Acoustic Mode in Toroidally Rotating Tokamaks  

E-Print Network [OSTI]

Geodesic acoustic mode (GAM) is analyzed by using gyro-kinetic equations applicable to low-frequency microinstabilities in a rotating axisymmetric plasma. Dispersion relation of GAM in the presence of arbitrary Mach number is analytically dervied. Toroidal rotation plays the same effects on the GAM regardless of the orientation of equilibrium flow. It is shown that the toroidal Mach number increases the GAM frequency and dramatically decreases the Landau damping rate. Classical gyro-kinetic equation is examined to be not suitable for describing the GAM in a torodially rotating tokamak plasma even for very small Mach number.

Ren, Haijun

2015-01-01T23:59:59.000Z

328

Discovery of a new mode of nuclear fission  

SciTech Connect (OSTI)

We measured the mass and kinetic-energy partitioning in the spontaneous fission of /sup 258/Fm, /sup 259/Md, /sup 260/Md, /sup 258/No, and /sup 260/(104). Surprisingly, these energy distributions were skewed upward or downward from the peak in each case, except for /sup 260/(104), indicating a composite of two energy distributions. We interpret this as a new mode of fission in which there is mixture of liquid-drop-like and fragment-shell-directed symmetric fission.

Hulet, E.K.; Wild, J.F.; Dougan, R.J.; Lougheed, R.W.; Landrum, J.H.; Dougan, A.D.; Schaedel, M.; Hahn, R.L.; Baisden, P.A.; Henderson, C.M.

1986-01-01T23:59:59.000Z

329

Failure mode and effect analysis using fuzzy analytic hierarchy process  

Science Journals Connector (OSTI)

This paper develops an evaluation model based on failure mode and effect analysis (FMEA) and fuzzy analytic hierarchy process (FAHP), to help the maintenance person for assessing the risk priority of the critical components in the paper industry to provide timely maintenance. Traditional FMEA determines risk priority number (RPN) by multiplying the scores of three factors. However the scores which are computed through traditional FMEA do not considere relative importance of the factors. The FAHP is used to compute the relative weights of the decision factors. A numerical example is used to illustrate the efficiency of the proposed model.

M. Ilangkumaran; P. Shanmugam; G. Sakthivel; K. Visagavel

2014-01-01T23:59:59.000Z

330

Curvature effect on tearing modes in presence of neoclassical friction  

SciTech Connect (OSTI)

Neoclassical physics (here associated to the poloidal variation of the magnetic field strength along field lines in a tokamak) is well known for driving self-generated plasma current and nonlinear magnetic islands associated to it in high performance, ITER relevant plasma discharges. It is demonstrated that the neoclassical friction between a magnetic perturbation and plasma flow already impacts magnetic islands in the linear regime, by inducing a weakening of curvature stabilization for tearing modes. This conclusion holds in particular for regimes where convection is influencing the pressure dynamics, as shown using a simple analytical model and confirmed in full Magneto-Hydro-Dynamics simulations.

Maget, Patrick; Mellet, Nicolas; Meshcheriakov, Dmytro; Garbet, Xavier [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France)] [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France); Ltjens, Hinrich [Centre de Physique Thorique, Ecole Polytechnique, CNRS (France)] [Centre de Physique Thorique, Ecole Polytechnique, CNRS (France)

2013-11-15T23:59:59.000Z

331

New modes of particle accelerations techniques and sources. Formal report  

SciTech Connect (OSTI)

This Report includes copies of transparencies and notes from the presentations made at the Symposium on New Modes of Particle Accelerations - Techniques and Sources, August 19-23, 1996 at the Institute for Theoretical Physics, University of California, Santa Barbara California, that was made available by the authors. Editing, reduction and changes to the authors contributions were made only to fulfill the printing and publication requirements. We would like to take this opportunity and thank the speakers for their informative presentations and for providing copies of their transparencies and notes for inclusion in this Report.

Parsa, Z. [ed.

1996-12-31T23:59:59.000Z

332

Close-spaced Knudsen`s mode thermionic converter  

SciTech Connect (OSTI)

It is demonstrated that the Knudsen`s mode of the thermionic converter (TIC) operation can be realized in a TIC with the interelectrode spacing 15{divided_by}30 {mu} and the emitter work function 5{divided_by}5.5 eV at the emitter temperature above 1800 K and cesium vapor pressure 0.5{divided_by}1 tor. With the use of reflective coating applied to the collector, efficiency of such TIC can achieve the level in excess of 30%.

Kucherov, R.Ya.; Nikolaev, Y.V. [Research Inst. of SIA Lutch, Podolsk (Russian Federation)

1995-12-31T23:59:59.000Z

333

Plasmonic modes and extinction properties of a random nanocomposite cylinder  

SciTech Connect (OSTI)

We study the properties of surface plasmon-polariton waves of a random metal-dielectric nanocomposite cylinder, consisting of bulk metal embedded with dielectric nanoparticles. We use the Maxwell-Garnett formulation to model the effective dielectric function of the composite medium and show that there exist two surface mode bands. We investigate the extinction properties of the system, and obtain the dependence of the extinction spectrum on the nanoparticles shape and concentration as well as the cylinder radius and the incidence angle for both TE and TM polarization.

Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)] [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)

2014-04-15T23:59:59.000Z

334

Beam dynamics studies for transverse electromagnetic mode type rf deflectors  

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

We have performed three-dimensional simulations of beam dynamics for transverse electromagnetic mode (TEM) type rf deflectors: normal and superconducting. The compact size of these cavities as compared to the conventional TM110 type structures is more attractive particularly at low frequency. Highly concentrated electromagnetic fields between the parallel bars provide strong electrical stability to the beam for any mechanical disturbance. An array of six 2-cell normal conducting cavities or a single cell superconducting structure is enough to produce the required vertical displacement at the target point. Both the normal and superconducting structures show very small emittance dilution due to the vertical kick of the beam.

Ahmed, Shahid; Krafft, Geoffrey A.; Deitrick, Kirsten; De Silva, Subashini U.; Delayen, Jean R.; Spata, Mike; Tiefenback, Michael; Hofler, Alicia; Beard, Kevin

2012-02-01T23:59:59.000Z

335

Composite slip table of dissimilar materials for damping longitudinal modes  

DOE Patents [OSTI]

A vibration slip table for use in a vibration testing apparatus is disclosed. The tables comprised of at least three composite layers of material; a first metal layer, a second damping layer, and a third layer having a high acoustic velocity relative to the first layer. The different acoustic velocities between the first and third layers cause relative shear displacements between the layers with the second layer damping the displacements between the first and third layers to reduce the table longitudinal vibration modes. 6 figures.

Gregory, D.L.; Priddy, T.G.; Smallwood, D.O.; Woodall, T.D.

1991-06-18T23:59:59.000Z

336

Mode-selective thermal radiation from a microparticle  

SciTech Connect (OSTI)

We experimentally demonstrate that thermal radiation from a micron-sized dielectric particle depends sensitively on its size and shape through the cavity quantum-electrodynamic effect. Our laser trapping technique levitated a high-temperature microsphere of Al{sub 2}O{sub 3} and enabled emission spectroscopy of the single particle. As the particle becomes smaller, a blackbodylike spectrum turns into a spectrum dominated by multiple peaks resonant with whispering gallery modes of the spherical resonator. The observed sharp frequency selectivity is applicable to spectral control of thermal radiation.

Odashima, Hitoshi; Tachikawa, Maki; Takehiro, Kei [Department of Physics, Meiji University, Kawasaki 214-8571 (Japan)

2009-10-15T23:59:59.000Z

337

Mode localization results and laboratory demonstration techniques with a multi-pendulum rig  

E-Print Network [OSTI]

. Perturbed system mode shapes, analytical, for R' = 0. 015. 16 Table III. Perturbed system mode shapes, analytical, for R' = 0. 04 (K, = 0. 908 N-m/rad, 1, = 0, 532 m). 17 Table IV. Perturbed system mode shapes, analytical, for R' = 0. 15 (K, = 3. 90 N.... Pendulum rig schematic Figure 2. Detail of pendulum rig. Figure 3. Graphical depiction of mode shapes given in Table I. 10 Figure 4. Depiction of perturbed mode shapes given in Table's II, III, and IV for: (a) Rs=0. 015; (b) R =0. 04; and (c) R =0. 15...

Bollich, Robert Kenneth Gerard

1992-01-01T23:59:59.000Z

338

Observation of a second-sound-like mode in superfluid-filled aerogel  

Science Journals Connector (OSTI)

Superfluid He4 is interesting acoustically because it can support more than one mode of sound propagation, and these can be used to study critical properties. Recently, there has been interest in superfluid-filled aerogels, but for such compressible materials one does not observe the ordinary (fourth) sound; instead there is a mode intermediate between first and fourth sound and a second-sound-like mode. We present a theory for the modes and the first observation of the aerogel second-sound-like mode, which is important because it propagates near the critical temperature.

M. J. McKenna; Tania Slawecki; J. D. Maynard

1991-04-08T23:59:59.000Z

339

Resistive ferromagnetic wall modes in theory and experiment  

SciTech Connect (OSTI)

Effects of the ferromagnetic resistive wall on the plasma stability are analyzed. The analysis is based on the equations describing the perturbation dynamics outside the plasma, assuming a linear plasma response. A single-mode cylindrical model is used with two features that differ from the standard case: the wall magnetic permeability is incorporated and the thin-wall approximation is waived. The derivations are performed so that the results can be applied to both tokamaks and line-tied pinches. This is done to allow conclusions for tokamaks from comparison of the developed theory with the experimental data on the resistive and ferromagnetic wall modes in the Wisconsin rotating wall machine with and without a ferritic wall [W. F. Bergerson, D. A. Hannum, C. C. Hegna, R. D. Kendrick, J. S. Sarff, and C. B. Forest, Phys. Rev. Lett. 101, 235005 (2008)]. The model shows that the ferromagnetic wall effect is always destabilizing. However, it must be small under standard conditions in tokamaks. The effect can be much stronger in the pinch with lower magnetic field and larger wall permeability. The dispersion relation obtained here makes possible an explanation of the experimental results available so far, including those from the Wisconsin machine reported recently as strongly contradictory to expectations based on earlier models. Also, an easy practical solution for compensating the destabilizing ferromagnetic effect in tokamaks is proposed.

Pustovitov, V. D. [Nuclear Fusion Institute, Russian Research Centre Kurchatov Institute, Kurchatov Square 1, Moscow 123182 (Russian Federation)

2009-05-15T23:59:59.000Z

340

H-Mode Accelerating Structures with PMQ Beam Focusing  

E-Print Network [OSTI]

We have developed high-efficiency normal-conducting RF accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of inter-digital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3-D modeling - electromagnetic computations, multi-particle beam-dynamics simulations with high currents, and thermal-stress analysis - for an IH-PMQ accelerator tank are presented. The accelerating field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. H-PMQ accelerating structures following a short RFQ can be used both in the front end of ion linacs or ...

Kurennoy, Sergey S; O'Hara, James F; Olivas, Eric R; Wangler, Thomas P

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

Mevva ion source operated in purely gaseous mode  

SciTech Connect (OSTI)

We have operated a vacuum arc ion source in such a way as to form beams of purely gaseous ions. The vacuum arc configuration that is conventionally used to produce intense beams of metal ions was altered so as to form gaseous ion beams, with only minimal changes to the external circuitry and no changes at all internally to the ion source. In our experiments we formed beams from oxygen (O{sup +} and O{sub 2}{sup +}), nitrogen (N{sup +} and N{sub 2}{sup +}), argon (Ar{sup +}) and carbon dioxide (C{sup +}, CO{sub 2}{sup +}, O{sup +} and O{sub 2}{sup +}) at extraction voltage of 2 to 50 kV. We used a pulsed mode of operation, with beam pulses approximately 50 milliseconds long and repetition rate 10 pulses per second, for a duty cycle of about 50%. Downstream ion beam current as measured by a 5 cm diameter Faraday cup was typically 0.5 mA pulse or about 250 {micro}A time averaged. This time averaged beam current is very similar to that obtained for metal ions when the source is operated in the usual vacuum arc mode. Here we describe the modifications made to the source and the results of our investigations.

Yushkov, G.Y.; MacGill, R.A.; Brown, I. G.

2003-03-27T23:59:59.000Z

342

Viscous damping of r-modes: Small amplitude instability  

Science Journals Connector (OSTI)

We study the viscous damping of r-modes of compact stars and analyze in detail the regions where small amplitude modes are unstable to the emission of gravitational radiation. We present general expressions for the viscous damping times for arbitrary forms of interacting dense matter and derive general semi-analytic results for the boundary of the instability region. These results show that many aspects, such as the physically important minima of the instability boundary, are surprisingly insensitive to detailed microscopic properties of the considered form of matter. Our general expressions are applied to the cases of hadronic stars, strange stars, and hybrid stars, and we focus on equations of state that are compatible with the recent measurement of a heavy compact star. We find that hybrid stars with a sufficiently small core can masquerade as neutron stars and feature an instability region that is indistinguishable from that of a neutron star, whereas neutron stars with a core density high enough to allow direct Urca reactions feature a notch on the right side of the instability region.

Mark G. Alford; Simin Mahmoodifar; Kai Schwenzer

2012-01-06T23:59:59.000Z

343

Variational principles with Pad approximants for tearing mode analysis  

SciTech Connect (OSTI)

Tearing modes occur in several distinct physical regimes, and it is often important to compute the inner layer response for these modes with various effects. There is a need for an approximate and efficient method of solving the inner layer equations in all these regimes. In this paper, we introduce a method of solving the inner layer equations based on using a variational principle with Pad approximants. For all the regimes considered, the main layer equations to be solved are inhomogeneous, and Pad approximants give a convenient and efficient method of satisfying the correct asymptotic behavior at the edge of the layer. Results using this variational principlePad approximant method in three of these regimes is presented. These regimes are the constant-? resistive-inertial (RI) regime, the constant-? viscoresistive regime, and the non-constant-? inviscid tearing regime. The last regime includes the constant-? RI regime and the inertial regime. The results show that reasonable accuracy can be obtained very efficiently with Pad approximants having a small number of parameters.

Cole, Andrew J. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States); Finn, John M. [Applied Mathematics and Plasma Physics, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Applied Mathematics and Plasma Physics, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

2014-03-15T23:59:59.000Z

344

Concentric core optical fiber with multiple-mode signal transmission  

DOE Patents [OSTI]

A concentric core optical fiber provides for the simultaneous but independent transmission of signals over a single optical fiber. The concentric optical fiber is constructed of a single-mode or multimode inner optical fiber defined by a core and a cladding of a lower index of refraction than the core and an outer optical fiber defined by additional cladding concentrically disposed around the cladding and of an index of refraction lower than the first mentioned cladding whereby the latter functions as the core of the outer optical fiber. By employing such an optical fiber construction with a single-mode inner core or optical fiber, highly sensitive interferometric and stable less sensitive amplitude based sensors can be placed along the same length of a concentric core optical fiber. Also, by employing the concentric core optical fiber secure telecommunications can be achieved via the inner optical fiber since an intrusion of the concentric optical fiber will first cause a variation in the light being transmitted through the outer optical fiber and this variation of light being used to trigger a suitable alarm indicative of the intrusion.

Muhs, Jeffrey D. (Lenoir City, TN)

1997-01-01T23:59:59.000Z

345

The quest for novel modes of excitation in exotic nuclei  

E-Print Network [OSTI]

This article provides an insight into several open problems in the quest for novel modes of excitation in nuclei with isospin asymmetry, deformation and finite temperature characteristic in stellar environment. Major unsolved problems include the nature of pygmy dipole resonances, the quest for various multipole and spin-isospin excitations both in neutron-rich and proton drip-line nuclei mainly driven by loosely bound nucleons, excitations in unstable deformed nuclei and evolution of their properties with the shape phase transition. Exotic modes of excitation in nuclei at finite temperatures characteristic for supernova evolution present open problems with possible impact in modeling astrophysically relevant weak interaction rates. All these issues challenge self-consistent many body theory frameworks at the frontiers of on-going research, including nuclear energy density functionals, both phenomenological and constrained by the strong interaction physics of QCD, models based on low-momentum two-nucleon interaction V_{low-k} and correlated realistic nucleon-nucleon interaction V_{UCOM}, supplemented by three-body force, as well as two-nucleon and three-nucleon interactions derived from the chiral effective field theory. Joined theoretical and experimental efforts, including research with radioactive isotope beams, are needed to provide insight into dynamical properties of nuclei away from the valley of stability, involving the interplay of isospin asymmetry, deformation and finite temperature.

N. Paar

2010-02-25T23:59:59.000Z

346

Electric sail control mode for amplified transverse thrust  

E-Print Network [OSTI]

The electric solar wind sail produces thrust by centrifugally spanned high voltage tethers interacting with the solar wind protons. The sail attitude can be controlled and attitude maneuvers are possible by tether voltage modulation synchronous with the sail rotation. Especially, the sail can be inclined with respect to the solar wind direction to obtain transverse thrust to change the osculating orbit angular momentum. Such an inclination has to be maintained by a continual control voltage modulation. Consequently, the tether voltage available for the thrust is less than the maximum voltage provided by the power system. Using a spherical pendulum as a model for a single rotating tether, we derive analytical estimations for the control efficiency for two separate sail control modes. One is a continuous control modulation that corresponds to strictly planar tether tip motion. The other is an on-off modulation with the tether tip moving along a closed loop on a saddle surface. The novel on-off mode is introduce...

Toivanen, Petri; Envall, Jouni

2014-01-01T23:59:59.000Z

347

Tritium minority heating with mode conversion of fast waves  

SciTech Connect (OSTI)

A new ion-heating scenario in tokamak plasmas, based on cyclotron damping of ion Bernstein waves (IBWs) by tritium minority at the first ion cyclotron harmonic (i.e., omega=2OMEGA{sub cT}), is proposed. The IBWs are coupled by mode conversion of fast magnetosonic waves in a D-H(T) (tritium minority in hydrogen-deuterium) plasma. The mode conversion layer is located near the center of the plasma column as well as the resonant layer of the tritium minority. A possible scenario for the JET (Joint European Torus) tokamak [J. Wesson, JET Report No. 99, 1999], based on the present idea, has been analyzed by means of the numerical codes TORIC and SSFPQL (toroidal ion cyclotron and steady state Fokker-Planck quasilinear) [M. Brambilla, Nucl. Fusion 34, 1121 (1994); Plasma Phys. Controlled Fusion 41, 1 (1999)]. As a result, tritium ions are accelerated up to energies close to the peak value of the DT cross section and steady state breakeven condition (Qapprox =1.3) can be reached with 25% minority tritium concentration.

Castaldo, Carmine; Cardinali, Alessandro [Euratom ENEA Association, Via Enrico Fermi 45, CP65, 00044 Frascati (Rome) (Italy)

2010-07-15T23:59:59.000Z

348

Stability of the electron-driven fishbone mode  

SciTech Connect (OSTI)

Electron-driven fishbones provide a good test bed for the linear theory of fast-particle driven instabilities as they exhibit a very high sensitivity to the details of both the equilibrium and the electronic distribution function. Thus, they can help validate the models developed for studying instabilities driven by alpha particles in future fusion reactors such as ITER. The fishbone dispersion relation is extended to properly account for resonance with passing particles by including the contribution of the parallel motion to the resonance condition. Barely passing electrons are found to drive the mode unstable at a lower frequency than barely trapped electrons. Although globally destabilizing, the influence of passing electrons quickly decreases away from the trapped-passing boundary. This is confirmed by an analysis using distributions close to those obtained in electron cyclotron resonance heating experiments. The major effect of this new resonance condition is a reduction of the fast-electron density threshold coupled to a reduction of the frequency of the mode.

Merle, Antoine; Decker, Joan; Garbet, Xavier; Sabot, Roland; Nicolas, Timothee [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Guimaraes-Filho, Zwinglio [Aix-Marseille Univ., IIFS-PIIM UMR 7345, F-13397 Marseille (France)

2012-07-15T23:59:59.000Z

349

1.3kW monolithic linearly-polarized single-mode MOPA and strategies for mitigating mode instabilities  

E-Print Network [OSTI]

We report on the high power amplification of 1064nm linearly-polarized laser in all-fiber polarization-maintained MOPA, which can operate at output power level of 1.3kW. The main amplifier was pumped with six 915nm laser diodes, and the slope efficiency is 65.3%. The beam quality (M2) was measured to be cladding large mode area fiber, and, by tight coiling of the gain fiber to the radius of 5.5cm, the MI threshold can be increased to 3 times higher than that without coiling or loose coiling. Experimental study has been carr...

Tao, Rumao; Wang, Xiaolin; Zhou, Pu; Liu, Zejin

2014-01-01T23:59:59.000Z

350

Electromechanical Mode Shape Estimation Based on Transfer Function Identification Using PMU Measurement  

SciTech Connect (OSTI)

Power system mode shapes are key indication of how dynamic components participate in low-frequency oscillations. Traditionally, mode shapes are calculated from a linearized dynamic model. For large-scale power systems, obtaining accu-rate dynamic models is very difficult. Therefore, measurement-based mode shape estimation methods have certain advantages, especially for the application of real-time small signal stability monitoring. In this paper, a measurement-based mode shape iden-tification method is proposed. The general relationship between transfer function (TF) and mode shape is derived. As an example, a least square (LS) method is implemented to estimate mode shape using an autoregressive exogenous (ARX) model. The per-formance of the proposed method is evaluated by Monte-Carlo studies using simulation data from a 17-machine model. The re-sults indicate the validity of the proposed method in estimating mode shapes with reasonably good accuracy

Zhou, Ning; Huang, Zhenyu; Dosiek, Luke; Trudnowski, Daniel J.; Pierre, John W.

2009-07-30T23:59:59.000Z

351

Appendix A: Preamble The mode(s) and risk of transmission for each specific disease agent included in Appendix A were reviewed.  

E-Print Network [OSTI]

Appendix A: Preamble The mode(s) and risk of transmission for each specific disease agent included in Appendix A were reviewed. Principle sources consulted for the development of disease literature was searched for evidence of person-to-person transmission in healthcare and non

Oliver, Douglas L.

352

Designing the Mode solving of the photonic crystal fiber via BPM and Exploring the Single-Mode Properties  

E-Print Network [OSTI]

Microstructured optical fibers (MOFs) are one of the most exciting recent developments in fiber optics. A MOF usually consists of a hexagonal arrangement of air holes running down the length of a silica fiber surrounding a central core of solid silica or, in some cases air. MOFs can exhibit a number of unique properties, including zero dispersion at visible wavelengths and low or high effective nonlinearity [3]-[17], By varying the size of the holes and their number and position, one can also design MOFs with carefully controlled dispersive and modal properties. In this paper, we analyze and modeling the behavior of the photonic crystal fiber (PCF) by using in the first step a propagator method based on the BPM method. With our BPM software, the electric field contour of the fundamental mode of PCF was demonstrated. We also used it to see the variation of the effective index; an effective index model confirms that such a fiber can be single mode for any wavelength. It would make a study of photonic crystal fi...

Debbal, Mohammed

2012-01-01T23:59:59.000Z

353

Microsoft Word - APS10_Highlight_I-mode  

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

Turbulent transport of heat and particles decoupled in a new operating Turbulent transport of heat and particles decoupled in a new operating regime observed on the Alcator-C tokamak Amanda E. Hubbard, hubbard@psfc.mit.edu MIT Plasma Science and Fusion Center, Cambridge MA 02139 USA Changes in edge turbulence result in increased heat confinement, advantageous for fusion, without unwanted confinement of particles. A key challenge in fusion energy is to confine the input heat long enough for the hot ionized hydrogen, fuel, or plasma, to fuse and produce net energy. Over 25 years ago, the spontaneous formation of an edge transport barrier was discovered, which roughly doubles the energy confinement [1]. This "high confinement", or H-mode, regime, is relied on in most 'tokamaks', a type of toroidal 'magnetic bottle', and foreseen for the international ITER project. However,

354

Exponentially Growing Tearing Modes in Rijnhuizen Tokamak Project Plasmas  

Science Journals Connector (OSTI)

The local measurement of the island width w, around the resonant surface, allowed a direct test of the extended Rutherford model [P. H. Rutherford, PPPL Report-2277 (1985)], describing the evolution of radiation-induced tearing modes prior to disruptions of tokamak plasmas. It is found that this model accounts very well for the observed exponential growth and supports radiation losses as being the main driving mechanism. The model implies that the effective perpendicular electron heat conductivity in the island is smaller than the global one. Comparison of the local measurements of w with the magnetic perturbed field B? showed that w?B?1/2 was valid for widths up to 18% of the minor radius.

F. Salzedas; F. C. Schller; A. A. M. Oomens; the RTP Team

2002-02-05T23:59:59.000Z

355

Bifurcation analysis of interacting stationary modes in thermohaline convection  

SciTech Connect (OSTI)

The Boussinesq equations for thermohaline convection in a finite two-dimensional box and with stress-free boundaries are considered. There are critical values of the aspect ratio at which the conduction state becomes unstable to two different roll patterns simultaneously. Near such a critical value a center manifold reduction allows us to reduce the dynamical behavior of the Boussinesq equations to a standard normal form equation that describes the interaction of two stationary modes. We present explicit analytical expressions for the linear and nonlinear coefficients on which the normal form depends. A numerical investigation of these coefficients leads to a division of the space of parameters (Prandtl number, solute Rayleigh number, Lewis number) into various regions that give rise to qualitatively different bifurcation behavior. Besides those encountered in ordinary convection, a variety of further phenomena is found, in particular in a vicinity of double tricritical points.

Neveling, M.; Dangelmayr, G.

1988-09-01T23:59:59.000Z

356

High-frequency acoustic modes in an ionic liquid  

Science Journals Connector (OSTI)

High-frequency collective dynamics of the ionic liquid 1-hexyl-3-methylimidazolium bromide [C6C1im]Br has been investigated by molecular dynamics simulations. Time correlation functions of mass current fluctuations were calculated for several wavevectors and the dispersion curves of excitations ?(k) for longitudinal and transverse acoustic sound modes were obtained at different temperatures and pressures. Two different thermodynamic states have the same high-frequency sound velocity irrespective of the temperature provided that both have the same density. Partial time correlation functions of mass currents were calculated for the atoms belonging to the polar or the non-polar domains resulting from the heterogeneous structure of [C6C1im]Br. The partial correlation functions indicate that the polar domains are stiffer than the non-polar domains of the simulated ionic liquid.

Mauro C. C. Ribeiro

2013-01-01T23:59:59.000Z

357

Efficient operating mode of the plasma wakefield accelerator  

SciTech Connect (OSTI)

A new operating mode of the plasma wakefield accelerator is found at which high efficiency of the driver-to-witness energy exchange can be achieved simultaneously with high transformer ratio and low energy spread. The efficient acceleration is realized in the blowout regime with a high-current moderate-length driver, if most of the driver and the whole witness are inside the cavern, and the beams are shaped to flatten the profile of the longitudinal electric field. The efficient regime can be demonstrated with state-of-the-art electron beams, but requires a longitudinal compression of the drive beam, high density plasma, and precise control of driver and witness shapes.

Lotov, K.V. [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation)

2005-05-15T23:59:59.000Z

358

Improved Spatial Resolution for Reflection Mode Infrared Microscopy  

SciTech Connect (OSTI)

Standard commercial infrared microscopes operating in reflection mode use a mirror to direct the reflected light from the sample to the detector. This mirror blocks about half of the incident light, however, and thus degrades the spatial resolution by reducing the umerical aperture of the objective. Here, we replace the mirror with a 50% beamsplitter to allow full illumination of the objective and retain a way to direct the reflected light to the detector. The improved spatial resolution is demonstrated using two different microscopes apable of diffraction-limited resolution: the first microscope is coupled to a synchrotron source and utilizes a single point detector, whereas the second microscope has a standard blackbody source and uses a focal planetarray (FPA) detector.

Bechtel, Hans A.; Martin, Michael C.; May, T.E.; Lerch, Philippe

2009-10-09T23:59:59.000Z

359

Baseline projections of transportation energy consumption by mode: 1981 update  

SciTech Connect (OSTI)

A comprehensive set of activity and energy-demand projections for each of the major transportation modes and submodes is presented. Projections are developed for a business-as-usual scenario, which provides a benchmark for assessing the effects of potential conservation strategies. This baseline scenario assumes a continuation of present trends, including fuel-efficiency improvements likely to result from current efforts of vehicle manufacturers. Because of anticipated changes in fuel efficiency, fuel price, modal shifts, and a lower-than-historic rate of economic growth, projected growth rates in transportation activity and energy consumption depart from historic patterns. The text discusses the factors responsible for this departure, documents the assumptions and methodologies used to develop the modal projections, and compares the projections with other efforts.

Millar, M; Bunch, J; Vyas, A; Kaplan, M; Knorr, R; Mendiratta, V; Saricks, C

1982-04-01T23:59:59.000Z

360

Cloud point determination using a thickness shear mode resonator  

SciTech Connect (OSTI)

Crude oils and crude oil products contain substantial amounts of petroleum waxes, consisting of a distribution of high molecular weight hydrocarbons. These waxes or paraffins have limited solubility in oil and tend to precipitate out at a temperature determined by the concentration and constituents of the wax. Precipitation and deposition of wax results in narrowing of pipelines, making crude oil recovery difficult. A parameter of practical importance is the wax precipitation temperature, traditionally known as the cloudpoint, at which visible crystallization occurs. Deposition problems arise in oil field operations at or below this temperature. Several techniques can be used to determine the cloud point: (1) visual observation, (2) viscosity measurement, (3) differential thermal analysis, and (4) pulsed nuclear magnetic resonance. This report describes a method for determination of cloud point with the use of a thickness shear mode resonator.

Spates, J.J. [Ktech Corp., Albuquerque, NM (United States); Martin, S.J.; Mansure, A.J. [Sandia National Lab., Albuquerque, NM (United States); Germer, J.W. [Petrolite Corp., St. Louis, MO (United States)

1995-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" from the National Library of EnergyBeta (NLEBeta).
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361

Design of double passive modulated mode-locked lasers  

SciTech Connect (OSTI)

A set of equations is obtained that allow the determination of the optimum values for the laser parameters in order to obtain perfect mode-locking by double passive modulation. The double modulation consists of a fast saturable absorber and a passive loss proportional to the mean intensity in the cavity provided by a passively driven electro-optic modulator. The stochastic nature of the emission of conventional passive modulated systems is eliminated if the correct values of the modulation parameters are chosen as predicted by the equations presented here. The predictions given by the equations were compared with previous numerical computations in order to check the validity of certain approximations used. Experimental results obtained confirm the predictions given by said equations.

Martinez, O.E.

1983-02-01T23:59:59.000Z

362

Failure Modes and Effects Analysis (FMEA) for wind turbines  

Science Journals Connector (OSTI)

The Failure Modes and Effects Analysis (FMEA) method has been used to study the reliability of many different power generation systems. This paper now applies that method to a wind turbine (WT) system using a proprietary software reliability analysis tool. Comparison is made between the quantitative results of an FMEA and reliability field data from real wind turbine systems and their assemblies. These results are discussed to establish relationships which are useful for future wind turbine designs. The main system studied is an existing design 2MW wind turbine with a Doubly Fed Induction Generator (DFIG), which is then compared with a hypothetical wind turbine system using the Brushless Doubly Fed Generator (BDFG) of the same rating. The software reliability analysis tool used for these studies was Relex Reliability Studio 2007 Version 2.

H. Arabian-Hoseynabadi; H. Oraee; P.J. Tavner

2010-01-01T23:59:59.000Z

363

275 C Downhole Switched-Mode Power Supply  

SciTech Connect (OSTI)

A vee-square (V2) control based controller IC is developed for a switch mode power supply capable of operating at extreme temperature/harsh environment conditions. A buck type regulator with silicon carbide power junction field effect transistors (JFET) as power devices is used to analyze the performance of controller. Special emphases are made on the analog sub-blocks--voltage reference, operational transconductance amplifier and comparator as individual building blocks. Transformer coupled gate drives and high temperature operable magnetic cores and capacitors are identified and tested for use in the design. Conventional ceramic chip packaging of ICs combined with lead carrier type mounting of passive filter components is introduced for hybrid packaging of the complete product. The developed SMPS is anticipated to support the operation of down-hole microcontrollers and other electronics devices that require low/medium power filtered dc inputs over an operating temperature of 275 C.

Chris Hutchens; Vijay Madhuravasal

2008-08-31T23:59:59.000Z

364

Security technologies and protocols for Asynchronous Transfer Mode networks  

SciTech Connect (OSTI)

Asynchronous Transfer Mode (ATM) is a new data communications technology that promises to integrate voice, video, and data traffic into a common network infrastructure. In order to fully utilize ATM`s ability to transfer real-time data at high rates, applications will start to access the ATM layer directly. As a result of this trend, security mechanisms at the ATM layer will be required. A number of research programs are currently in progress which seek to better understand the unique issues associated with ATM security. This paper describes some of these issues, and the approaches taken by various organizations in the design of ATM layer security mechanisms. Efforts within the ATM Forum to address the user communities need for ATM security are also described.

Tarman, T.D.

1996-06-01T23:59:59.000Z

365

Generation of Geodesic Acoustic Modes in ITG turbulence  

SciTech Connect (OSTI)

The generation of geodesic acoustic modes (GAM) is studied by means of numerical simulations of a 3D fluid global model, describing flux-driven electrostatic ITG (Ion Temperature Gradient) turbulence in the core of tokamak plasmas. The model evolves the equilibrium and the perturbed fields as a whole. The coupling of poloidal harmonics induced by the curvature thus results in the presence of both turbulent and neoclassical transport effects in the system. The neoclassical thermal conductivity, which is linked to the time-independent component of the poloidal modulation of the equilibrium fields, is observed to be of the order of the turbulent one, in a system driven by strong injected heat fluxes. The frequency spectrum of the electrostatic potential fluctuations exhibits a peak near the theoretical GAM frequency. In the turbulent stationary state of the simulations a downshift of the GAM frequency is observed.

Falchetto, G. L.; Garbet, X.; Ottaviani, M. [Association EURATOM-CEA, CEA/DSM/DRFC, Centre de Cadarache, 13108 Saint Paul lez Durance (France); Smolyakov, A. [Department of Physics and Engineering Physics, University of Saskatchewan, SK (Canada)

2006-11-30T23:59:59.000Z

366

Entanglement conditions for two-mode states: Applications  

E-Print Network [OSTI]

on the entanglement condition #5;#6;ab?#7;#5;2 #1; #6;NaNb#7; , #1;1#2; that is, if the two modes are in a state for which the above inequality is satisfied, the state is entangled #3;13#4;. The quan- tities in this inequality can be measured in a relatively... that #5;#6;ab?#7;#5;2= #6;NaNb#7;. One way of possibly finding states that satisfy our entangle- ment condition, Eq. #1;1#2;, is to start with a product of coherent states and perturbing this state in such a way as to produce entanglement. We give two...

Hillery, Mark; Zubairy, M. Suhail

2006-01-01T23:59:59.000Z

367

Spatiotemporal reconstruction of list-mode PET data  

SciTech Connect (OSTI)

We describe a method for computing a continuous time estimate of tracer density using list-mode positron emission tomography data. The rate function in each voxel is modeled as an inhomogeneous Poisson process whose rate function can be represented using a cubic B-spline basis. The rate functions are estimated by maximizing the likelihood of the arrival times of detected photon pairs over the control vertices of the spline, modified by quadratic spatial and temporal smoothness penalties and a penalty term to enforce nonnegativity. Randoms rate functions are estimated by assuming independence between the spatial and temporal randoms distributions. Similarly, scatter rate functions are estimated by assuming spatiotemporal independence and that the temporal distribution of the scatter is proportional to the temporal distribution of the trues. A quantitative evaluation was performed using simulated data and the method is also demonstrated in a human study using 11C-raclopride.

Nichols, Thomas E.; Qi, Jinyi; Asma, Evren; Leahy, Richard M.

2002-03-01T23:59:59.000Z

368

Quench Propagation Ignition using Single-Mode Diode Laser  

E-Print Network [OSTI]

The stability of NbTi-based multifilamentary composite wires subjected to local heat disturbances of short durations is studied in pool boiling helium conditions. A new type of heater is being developed to characterize the superconducting to normal state transition. It relies on a single-mode Diode Laser with an optical fiber illuminating the wire surface. This first paper focuses mainly on the feasibility of this new heater technology and eventually discusses the difficulties related to it. A small overview of Diode Lasers and optical fibers revolving around our application is given. Then, we describe the experimental setup, and present some recorded voltage traces of transition and recovery processes. In addition, we present also some energy and Normal Zone Propagation Velocity data and we outline ameliorations that will be done to the system.

Trillaud, F; Devred, Arnaud; Fratini, M; Leboeuf, D; Tixador, P

2005-01-01T23:59:59.000Z

369

Influence of heavy modes on perturbations in multiple field inflation  

SciTech Connect (OSTI)

We investigate linear cosmological perturbations in multiple field inflationary models where some of the directions are light while others are heavy (with respect to the Hubble parameter). By integrating out the massive degrees of freedom, we determine the multi-dimensional effective theory for the light degrees of freedom and give explicitly the propagation matrix that replaces the effective sound speed of the one-dimensional case. We then examine in detail the consequences of a sudden turn along the inflationary trajectory, in particular the possible breakdown of the low energy effective theory in case the heavy modes are excited. Resorting to a new basis in field space, instead of the usual adiabatic/entropic basis, we study the evolution of the perturbations during the turn. In particular, we compute the power spectrum and compare with the result obtained from the low energy effective theory.

Gao, Xian; Langlois, David [Astroparticule et Cosmologie (APC), UMR 7164-CNRS, Universit Denis Diderot-Paris 7, 10 rue Alice Domon et Lonie Duquet, 75205 Paris (France); Mizuno, Shuntaro, E-mail: xgao@apc.univ-paris7.fr, E-mail: langlois@apc.univ-paris7.fr, E-mail: shuntaro.mizuno@th.u-psud.fr [Laboratoire de Physique Thorique, Universit Paris-Sud 11 et CNRS, Btiment 210, 91405 Orsay Cedex (France)

2012-10-01T23:59:59.000Z

370

Linear calculations of edge current driven kink modes with BOUT++ code  

SciTech Connect (OSTI)

This work extends previous BOUT++ work to systematically study the impact of edge current density on edge localized modes, and to benchmark with the GATO and ELITE codes. Using the CORSICA code, a set of equilibria was generated with different edge current densities by keeping total current and pressure profile fixed. Based on these equilibria, the effects of the edge current density on the MHD instabilities were studied with the 3-field BOUT++ code. For the linear calculations, with increasing edge current density, the dominant modes are changed from intermediate-n and high-n ballooning modes to low-n kink modes, and the linear growth rate becomes smaller. The edge current provides stabilizing effects on ballooning modes due to the increase of local shear at the outer mid-plane with the edge current. For edge kink modes, however, the edge current does not always provide a destabilizing effect; with increasing edge current, the linear growth rate first increases, and then decreases. In benchmark calculations for BOUT++ against the linear results with the GATO and ELITE codes, the vacuum model has important effects on the edge kink mode calculations. By setting a realistic density profile and Spitzer resistivity profile in the vacuum region, the resistivity was found to have a destabilizing effect on both the kink mode and on the ballooning mode. With diamagnetic effects included, the intermediate-n and high-n ballooning modes can be totally stabilized for finite edge current density.

Li, G. Q., E-mail: ligq@ipp.ac.cn; Xia, T. Y. [Institute of Plasma Physics, CAS, Hefei, Anhui 230031 (China); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Xu, X. Q. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Snyder, P. B.; Turnbull, A. D. [General Atomics, San Diego, California 92186 (United States); Ma, C. H.; Xi, P. W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); FSC, School of Physics, Peking University, Beijing 100871 (China)

2014-10-15T23:59:59.000Z

371

Global gyrokinetic stability of collisionless microtearing modes in large aspect ratio tokamaks  

SciTech Connect (OSTI)

Linear full radius gyrokinetic calculations show the existence of unstable microtearing modes (MTMs) in purely collisionless, high temperature, large aspect ratio tokamak plasmas. The present study takes into account fully gyrokinetic highly passing ions and electrons. The global 2-D structures of the collisionless mode with full radius coupling of the poloidal modes is obtained and compared with another electromagnetic mode, namely, the Alfvn Ion Temperature Gradient (AITG) mode (or Kinetic Ballooning Mode, KBM) for the same equilibrium profile. Several important characteristics of the modes are brought out and compared, such as a clear signature in the symmetry properties of the two modes, the plasma? dependence, and radial and poloidal length scales of the electrostatic and magnetic vector potential fluctuations. Extensive parameter scans for this collisionless microtearing mode reveal the scaling of the growth rate with ? and the electron temperature gradient ?{sub e}. Scans at different ? values show an inverse relationship between the ?{sub e} threshold and ?, leading to a stability diagram, and implying that the mode might exist at moderate to strong temperature gradients for finite ? plasmas in large aspect ratio tokamaks. In contrast to small aspect ratio tokamaks where the trapped electron magnetic drift resonance is found to be important, in large aspect ratio tokamaks, a strong destabilization due to the magnetic drift resonance of passing electrons is observed and is identified as a possible collisionless drive mechanism for the collisionless MTM.

Swamy, Aditya K.; Ganesh, R., E-mail: ganesh@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar (India); Chowdhury, J. [Department of Physics, University of Colorado, Boulder, Colorado 80309 (United States); Brunner, S.; Vaclavik, J.; Villard, L. [CRPP, EPFL, 1015 Lausanne (Switzerland)

2014-08-15T23:59:59.000Z

372

Phase space theory of Bose-Einstein condensates and time-dependent modes  

E-Print Network [OSTI]

A phase space theory approach for treating dynamical behaviour of Bose-Einstein condensates applicable to situations such as interferometry with BEC in time-dependent double well potentials is presented. Time-dependent mode functions are used, chosen so that one, two,.. highly occupied modes describe well the physics of interacting condensate bosons in time dependent potentials at well below the transition temperature. Time dependent mode annihilation, creation operators are represented by time dependent phase variables, but time independent total field annihilation, creation operators are represented by time independent field functions. Two situations are treated, one (mode theory) is where specific mode annihilation, creation operators and their related phase variables and distribution functions are dealt with, the other (field theory) is where only field creation, annihilation operators and their related field functions and distribution functionals are involved. The paper focuses on the hybrid approach, where the modes are divided up between condensate (highly occupied) modes and non-condensate (sparsely occupied) modes. It is found that there are extra terms in the Ito stochastic equations both for the stochastic phases and stochastic fields, involving coupling coefficients defined via overlap integrals between mode functions and their time derivatives. For the hybrid approach both the Fokker-Planck and functional Fokker-Planck equations differ from those derived via the correspondence rules, the drift vectors are unchanged but the diffusion matrices contain additional terms involving the coupling coefficients. Results are also presented for the combined approach where all the modes are treated as one set.

B. J. Dalton

2012-07-20T23:59:59.000Z

373

Failure modes and effects analysis of fusion magnet systems  

SciTech Connect (OSTI)

A failure modes and consequence analysis of fusion magnet system is an important contributor towards enhancing the design by improving the reliability and reducing the risk associated with the operation of magnet systems. In the first part of this study, a failure mode analysis of a superconducting magnet system is performed. Building on the functional breakdown and the fault tree analysis of the Toroidal Field (TF) coils of the Next European Torus (NET), several subsystem levels are added and an overview of potential sources of failures in a magnet system is provided. The failure analysis is extended to the Poloidal Field (PF) magnet system. Furthermore, an extensive analysis of interactions within the fusion device caused by the operation of the PF magnets is presented in the form of an Interaction Matrix. A number of these interactions may have significant consequences for the TF magnet system particularly interactions triggered by electrical failures in the PF magnet system. In the second part of this study, two basic categories of electrical failures in the PF magnet system are examined: short circuits between the terminals of external PF coils, and faults with a constant voltage applied at external PF coil terminals. An electromagnetic model of the Compact Ignition Tokamak (CIT) is used to examine the mechanical load conditions for the PF and the TF coils resulting from these fault scenarios. It is found that shorts do not pose large threats to the PF coils. Also, the type of plasma disruption has little impact on the net forces on the PF and the TF coils. 39 refs., 30 figs., 12 tabs.

Zimmermann, M; Kazimi, M S; Siu, N O; Thome, R J

1988-12-01T23:59:59.000Z

374

Benchmarking kinetic calculations of resistive wall mode stability  

SciTech Connect (OSTI)

Validating the calculations of kinetic resistive wall mode (RWM) stability is important for confidently predicting RWM stable operating regions in ITER and other high performance tokamaks for disruption avoidance. Benchmarking the calculations of the Magnetohydrodynamic Resistive SpectrumKinetic (MARS-K) [Y. Liu et al., Phys. Plasmas 15, 112503 (2008)], Modification to Ideal Stability by Kinetic effects (MISK) [B. Hu et al., Phys. Plasmas 12, 057301 (2005)], and Perturbed Equilibrium Nonambipolar Transport (PENT) [N. Logan et al., Phys. Plasmas 20, 122507 (2013)] codes for two Solov'ev analytical equilibria and a projected ITER equilibrium has demonstrated good agreement between the codes. The important particle frequencies, the frequency resonance energy integral in which they are used, the marginally stable eigenfunctions, perturbed Lagrangians, and fluid growth rates are all generally consistent between the codes. The most important kinetic effect at low rotation is the resonance between the mode rotation and the trapped thermal particle's precession drift, and MARS-K, MISK, and PENT show good agreement in this term. The different ways the rational surface contribution was treated historically in the codes is identified as a source of disagreement in the bounce and transit resonance terms at higher plasma rotation. Calculations from all of the codes support the present understanding that RWM stability can be increased by kinetic effects at low rotation through precession drift resonance and at high rotation by bounce and transit resonances, while intermediate rotation can remain susceptible to instability. The applicability of benchmarked kinetic stability calculations to experimental results is demonstrated by the prediction of MISK calculations of near marginal growth rates for experimental marginal stability points from the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 (2000)].

Berkery, J. W.; Sabbagh, S. A. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Wang, Z. R.; Logan, N. C.; Park, J.-K.; Manickam, J. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Betti, R. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)] [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

2014-05-15T23:59:59.000Z

375

High-Throughput Mode Liquid Microjunction Surface Sampling Probe  

SciTech Connect (OSTI)

A simple and automated spot sampling operation mode for a liquid microjunction surface sampling probe/electrospray ionization mass spectrometry (LMJ-SSP/ESI-MS) system is reported. Prior manual and automated spot sampling methods with this probe relied on a careful, relatively slow alignment of the probe and surface distance (<20 m spacing) to form the probe-to-surface liquid microjunction critical to successful surface sampling. Moreover, sampling multiple spots required retraction of the surface from the probe and a repeat of this careful probe-to-surface distance alignment at the next sampling position. With the method described here, the probe was not positioned as close to the surface, the exact probeto-surface positioning was found to be less critical (spanning distances from about 100-300 m), and this distance was not altered during the sampling of an entire array of sample spots. With the probe positioned within the appropriate distance from the surface, the liquid microjunction was formed by letting the liquid from the sampling end of the probe extend out from the probe to the surface. This was accomplished by reducing the selfaspiration liquid flow rate of the probe to a value less than the volume flow rate pumped into the probe. When the self-aspiration rate of the probe was subsequently increased, analytes on the surface that dissolved at the liquid microjunction were aspirated back into the probe with the liquid that created the liquid microjunction and electrosprayed. Presented here are the basics of this new sampling mode, as well as data that illustrate the potential analytical capabilities of the device to conduct highthroughput quantitative analysis.

Van Berkel, Gary J [ORNL; Kertesz, Vilmos [ORNL; King, Richard C. [PharmaCadence

2009-01-01T23:59:59.000Z

376

Field Quantization, Photons and Non-Hermitean Modes  

E-Print Network [OSTI]

Field quantization in three dimensional unstable optical systems is treated by expanding the vector potential in terms of non-Hermitean (Fox-Li) modes in both the cavity and external regions. The cavity non-Hermitean modes (NHM) are treated using the paraxial and monochromaticity approximations. The NHM bi-orthogonality relationships are used in a standard canonical quantization procedure based on introducing generalised coordinates and momenta for the electromagnetic (EM) field. The quantum EM field is equivalent to a set of quantum harmonic oscillators (QHO), associated with either the cavity or the external region NHM. This confirms the validity of the photon model in unstable optical systems, though the annihilation and creation operators for each QHO are not Hermitean adjoints. The quantum Hamiltonian for the EM field is the sum of non-commuting cavity and external region contributions, each of which is sum of independent QHO Hamiltonians for each NHM, but the external field Hamiltonian also includes a coupling term responsible for external NHM photon exchange processes. Cavity energy gain and loss processes is associated with the non-commutativity of cavity and external region operators, given in terms of surface integrals involving cavity and external region NHM functions on the cavity-external region boundary. The spontaneous decay of a two-level atom inside an unstable cavity is treated using the essential states approach and the rotating wave approximation. Atomic transitions leading to cavity NHM photon absorption have a different coupling constant to those leading to photon emission, a feature resulting from the use of NHM functions. Under certain conditions the decay rate is enhanced by the Petermann factor.

S. A. Brown; B. J. Dalton

2001-09-10T23:59:59.000Z

377

Peeling-off of the external kink modes at tokamak plasma edge  

E-Print Network [OSTI]

It is pointed that there is a current jump between the edge plasma inside the last closed magnetic surface and the scrape-off layer and the current jump can lead the external kink modes to convert to the tearing modes, due to the current interchange effects [L. J. Zheng and M. Furukawa, Phys. Plasmas 17, 052508 (2010)]. The magnetic reconnection in the presence of tearing modes subsequently causes the tokamak edge plasma to be peeled off to link to the diverters. In particular, the peeling or peeling-ballooning modes can become the "peeling-off" modes in this sense. This phenomenon indicates that the tokamak edge confinement can be worse than the expectation based on the conventional kink mode picture.

Zheng, L J

2014-01-01T23:59:59.000Z

378

Optimum phase noise reduction and repetition rate tuning in quantum-dot mode-locked lasers  

SciTech Connect (OSTI)

Competing approaches exist, which allow control of phase noise and frequency tuning in mode-locked lasers, but no judgement of pros and cons based on a comparative analysis was presented yet. Here, we compare results of hybrid mode-locking, hybrid mode-locking with optical injection seeding, and sideband optical injection seeding performed on the same quantum dot laser under identical bias conditions. We achieved the lowest integrated jitter of 121 fs and a record large radio-frequency (RF) tuning range of 342?MHz with sideband injection seeding of the passively mode-locked laser. The combination of hybrid mode-locking together with optical injection-locking resulted in 240 fs integrated jitter and a RF tuning range of 167?MHz. Using conventional hybrid mode-locking, the integrated jitter and the RF tuning range were 620 fs and 10?MHz, respectively.

Habruseva, T. [CAPPA, Cork Institute of Technology, Cork (Ireland); Tyndall National Institute, Lee Maltings, Cork (Ireland); Aston University, Aston Triangle, B4 7ET Birmingham (United Kingdom); Arsenijevi?, D.; Kleinert, M.; Bimberg, D. [Institut fr Festkrperphysik, Technische Universitt Berlin, Berlin (Germany); Huyet, G.; Hegarty, S. P. [CAPPA, Cork Institute of Technology, Cork (Ireland); Tyndall National Institute, Lee Maltings, Cork (Ireland)

2014-01-13T23:59:59.000Z

379

Excitation of coupled ion lattice-streaming carrier modes in high mobility semiconductors  

SciTech Connect (OSTI)

Interaction between streaming carrier plasmons and lattice vibrations in ultrahigh mobility materials generates novel, hybrid, lattice-streaming carrier modes. The Boltzmann kinetic equation for a collisionless carrier response is employed to obtain a dispersion relation including the effects of thermal velocity spreads. The resulting slow electrostatic (ES) modes involve plasmon-phonon (PP) coupling, while the fast electromagnetic (EM) modes involve plasmon-photon-phonon coupling. There is an unstable parameter regime leading to spontaneous growth of slow ES PP modes from noise. Thermal spreads reduce but do not eliminate the growth rate. The fast EM modes are found to be stable and slightly damped over the parameter regime. Spontaneous growth of ES modes carries implications for terahertz generation in high mobility materials.

Riyopoulos, S. [Science Applications International Corporation, McLean, Virginia 22102 (United States)

2009-03-15T23:59:59.000Z

380

One-dimensional full wave simulation on XB mode conversion in electron cyclotron heating  

SciTech Connect (OSTI)

The XB mode conversion in electron cyclotron resonance frequency heating has been studied in detail through 1D full wave simulation. The field pattern depends on the density scale length, and the wave absorption near upper hybrid resonance is maximized beyond the R(X) mode cutoff density for optimized density scale length. The simulated mode conversion efficiency has been compared with that of an analytic formula, showing good agreements except for the phase dependent term of the X wave. The mode conversion efficiency is calculated for oblique injections as well, and it is found that the efficiency decreases as the injection angles increases. Short magnetic field scale length is confirmed to relax the short density scale length condition maximizing the XB mode conversion efficiency. Finally, the simulation code is used to analyze the mode conversion and power absorption of a pre-ionization plasma in versatile experiment spherical torus.

Kim, S. H., E-mail: shkim95@kaeri.re.kr [Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Lee, H. Y.; Jo, J. G.; Hwang, Y. S. [Seoul National University, Seoul 151-742 (Korea, Republic of)

2014-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

Mixed mode (I+II) fracture toughness of polymer nanoclay nanocomposites  

Science Journals Connector (OSTI)

Abstract In this work the mixed mode fracture behaviour (I+II) of an epoxy/nanoclay nanocomposite system is analysed, discussing the results from Single Edge Notch Bending tests. It is found that nanomodification significantly enhances the fracture toughness of the epoxy resin on the entire range of mixed mode loadings (from pure mode I to pure mode II), improvements depend however on the mode mixity. Experimental results are compared to theoretical predictions based on different criteria for mixed mode fracture in brittle homogeneous materials. As expected, it is found that, while the data from pure epoxy are satisfactorily predicted almost independently of the adopted approach, the agreement is much worse in the case of nanomodified materials. Explanations of this behaviour can be found in the emergence of additional microscale and nanoscale toughening mechanisms due to nanomodification not properly described by conventional models.

Michele Zappalorto; Marco Salviato; Marino Quaresimin

2013-01-01T23:59:59.000Z

382

Hopf-Turing mixed mode and pattern selection in reaction diffusion systems  

E-Print Network [OSTI]

The amplitude equation of Gierer-Mainhardt model has been actually derived near the boundary abuot which Turing and Hopf modes exist. In a parameter region where Hopf-Turing mixed mode solution is stable, a chaotic state that generally results from interaction between mixed modes, is observed. This chaotic region follows a strong selection of a spatially periodic order followed by a local, resonant, very large frequency temporal oscillation. A spatio-temporal forcing, responsible for what obseved, has been identified.

A. Bhattacharyay

2001-11-27T23:59:59.000Z

383

External kink modes as a model for MHD activity associated with ELMs  

SciTech Connect (OSTI)

Tokamak plasmas in the high confinement mode of operation are known to exhibit edge localized activity referred to as ELMs. A model is proposed for the underlying cause in terms of the external kink mode. The build up of the current density near the plasma edge is shown to decrease the shear in the safety-factor, q, profile and lead to destabilization of the kink mode. The role of the plasma geometry and equilibrium profiles is discussed.

Manickam, J.

1992-01-01T23:59:59.000Z

384

QUANTITATIVE TESTS OF ELMS AS INTERMEDIATE N PEELING-BALLOONING MODES  

SciTech Connect (OSTI)

OAK A271 QUANTITATIVE TESTS OF ELMS AS INTERMEDIATE N PEELING-BALLOONING MODES. Two of the major issues crucial for the design of the next generation tokamak burning plasma devices are the predictability of the edge pedestal height and control of the divertor heat load in H-mode configurations. Both of these are strongly impacted by edge localized modes (ELMs) and their size. A working model for ELMs is that they are intermediate toroidal mode number, n {approx} 5-30, peeling-ballooning modes driven by the large edge pedestal pressure gradient P{prime} and the associated large edge bootstrap current density J{sub BS}. the interplay between P{prime} and J{sub BS} as a discharge evolves can excite peeling-ballooning modes over a wide spectrum of n. The pedestal current density plays a dual role by stabilizing the high n ballooning modes via opening access to second stability but providing free energy to drive the intermediate n peeling modes. This makes a systematic evaluation of this model particularly challenging. This paper describes recent quantitative tests of this model using experimental data from the DIII-D and the JT-60U tokamaks. These tests are made possible by recent improvements to the ELITE MHD stability code, which allow an efficient evaluation of the unstable peeling-ballooning modes, as well as by improvements to other diagnostic and analysis techniques. Some of the key testable features of this model are: (1) ELMs are triggered when the growth rates of intermediate n MHD modes become significantly large; (2) ELM sizes are related to the radial widths of the unstable modes; (3) the unstable modes have a strong ballooning character localized in the outboard bad curvature region; (4) at high collisionality, ELM size generally becomes smaller because J{sub BS} is reduced.

LAO, LL; SNYDER, PB; LEONARD, AW; OSBORNE, TH; PETRIE, TW; FERRON, JR; GROEBNER, RJ; HORTON, LD; KAMADA, Y; MURAKAMI, M; OIKAWA, T; PEARLSTEIN, LD; SAARELMA, S; STJOHN, HE; THOMAS, DM; TURNBULL, AD; WILSON, HR

2002-07-01T23:59:59.000Z

385

Mode-locked terahertz quantum cascade laser by direct phase synchronization  

SciTech Connect (OSTI)

Mode-locking of a terahertz quantum cascade laser is achieved using multimode injection seeding. Contrary to standard methods that rely on gain modulation, here a fixed phase relationship is directly imprinted to the laser modes. In this work, we demonstrate the generation of 9 ps phase mode-locked pulses around 2.75 THz. A direct measurement of the emitted field phase shows that it results from the phase of the initial injection.

Maussang, K.; Maysonnave, J.; Jukam, N.; Freeman, J. R.; Cavali, P.; Dhillon, S. S.; Tignon, J. [Laboratoire Pierre Aigrain, Ecole Normale Suprieure, CNRS (UMR 8551), Universit P. et M. Curie, Universit D. Diderot, 75005 Paris (France); Khanna, S. P.; Linfield, E. H.; Davies, A. G. [School of Electronic and Electrical Engineering, University of Leeds, Leeds LS9 2JT (United Kingdom); Beere, H. E.; Ritchie, D. A. [University of Cambridge, Cavendish Lab, Cambridge CB3 0HE (United Kingdom)

2013-12-04T23:59:59.000Z

386

Quantum-State Engineering of Multiple Trapped Ions for Center-of-Mass Mode  

E-Print Network [OSTI]

We propose a scheme to generate a superposition with arbitrary coefficients on a line in phase space for the center-of-mass vibrational mode of N ions by means of isolating all other spectator vibrational modes from the center-of-mass mode. It can be viewed as the generation of previous methods for preparing motional states of one ion. For large number of ions, we need only one cyclic operatin to generate such a superposition of many coherent states.

Hao-Sheng Zeng; Xi-Wen Zhu; Ke-Lin Gao

2000-10-31T23:59:59.000Z

387

Nuclear reaction rates and energy in stellar plasmas : The effect of highly damped modes  

E-Print Network [OSTI]

The effects of the highly damped modes in the energy and reaction rates in a plasma are discussed. These modes, with wavenumbers $k \\gg k_{D}$, even being only weakly excited, with less than $k_{B}T$ per mode, make a significant contribution to the energy and screening in a plasma. When the de Broglie wavelength is much less than the distance of closest approach of thermal electrons, a classical analysis of the plasma can

Merav Opher; Luis O. Silva; Dean E. Dauger; Viktor K. Decyk; John M. Dawson

2001-05-09T23:59:59.000Z

388

Evidence for energy coupling from the SiD vibration mode to the SiSi and SiO vibration modes at the SiO2 Si interface  

E-Print Network [OSTI]

. Jackson, Appl. Phys. Lett., 69, 2441 1996 , we measured the Si­H, Si­D, and other vibrational modes vibrational modes. In this letter, we present the experimental measurement of vibrational modes at the SiO2Evidence for energy coupling from the Si­D vibration mode to the Si­Si and Si­O vibration modes

Chen, Zhi

389

Zonal flows generated by small-scale drift-Alfven modes  

SciTech Connect (OSTI)

The generation of zonal flows by small-scale drift-Alfven (SSDA) modes is investigated. It is shown that these zonal flows can be generated by a monochromatic wave packet of SSDA modes propagating in the ion diamagnetic drift direction. The corresponding zonal-flow instability resembles a hydrodynamic one. Its growth rate depends on the spectrum purity of the wave packet; it decreases for relatively weak spectrum broadening and the instability turns into a resonant one, and eventually is suppressed, as the broadening increases. A general conclusion of this work is that the SSDA modes are less effective for driving zonal flows than standard drift modes.

Mikhailovskii, A.B.; Smolyakov, A.I.; Kovalishen, E.A.; Shirokov, M.S.; Tsypin, V.S.; Botov, P.V.; Galvao, R.M.O. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation) and Nonlinear Physics Laboratory, Moscow Institute of Physics and Technology, Institutskii per. 9, Dolgoprudnyi 141700, Moscow Region (Russian Federation); University of Saskatchewan, 116 Science place, Saskatoon S7 N 5E2 (Canada) and Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation); Nonlinear Physics Laboratory, Moscow Institute of Physics and Technology, Institutskii per. 9, Dolgoprudnyi 141700, Moscow Region (Russian Federation) and Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation); Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow 123182 (Russian Federation) and Moscow Engineering Physics Institute, Kashirskoe Shosse 31, Moscow 115409 (Russian Federation); Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo (Brazil); Nonlinear Physics Laboratory, Moscow Institute of Physics and Technology, Institutskii per. 9, Dolgoprudnyi 141700, Moscow Region (Russian Federation) and Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, Kurchatov Sq., 1, Moscow, 123182 (Russian Federation); Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo (Brazil) and Brazilian Center for Research in Physics, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil)

2006-04-15T23:59:59.000Z

390

Synthesis and analysis of planar optical waveguides with prescribed TM modes  

Science Journals Connector (OSTI)

An inverse-scattering approach to designing optical waveguides with prescribed propagation characteristics of TM modes is presented. The refractive-index profile of the waveguide is...

Tamil, Lakshman S; Lin, Yun

1993-01-01T23:59:59.000Z

391

Study of a high-order-mode gyrotron traveling-wave amplifier  

SciTech Connect (OSTI)

Physics and performance issues of a TE{sub 01}-mode gyrotron traveling-wave amplifier are studied in theory. For a high order mode, absolute instabilities on neighboring modes at the fundamental and higher cyclotron harmonic frequencies impose severe constraints to the device capability. Methods for their stabilization are outlined, on the basis of which the performance characteristics are examined in a multidimensional parameter space under the marginal stability criterion. The results demonstrate the viability of a high-order-mode traveling-wave amplifier and provide a roadmap for design tradeoffs among power, bandwidth, and efficiency. General trends are observed and illustrated with specific examples.

Chiu, C. C.; Tsai, C. Y.; Kao, S. H. [Department of Physics, National Tsing Hua University, Hsinchu 30043, Taiwan (China); Chu, K. R. [Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Barnett, L. R.; Luhmann, N. C. Jr. [Department of Applied Science, University of California, Davis, California 95616 (United States)

2010-11-15T23:59:59.000Z

392

New method for computing ideal MHD normal modes in axisymmetric toroidal geometry  

SciTech Connect (OSTI)

Analytic elimination of the two magnetic surface components of the displacement vector permits the normal mode ideal MHD equations to be reduced to a scalar form. A Galerkin procedure, similar to that used in the PEST codes, is implemented to determine the normal modes computationally. The method retains the efficient stability capabilities of the PEST 2 energy principle code, while allowing computation of the normal mode frequencies and eigenfunctions, if desired. The procedure is illustrated by comparison with earlier various of PEST and by application to tilting modes in spheromaks, and to stable discrete Alfven waves in tokamak geometry.

Wysocki, F.; Grimm, R.C.

1984-11-01T23:59:59.000Z

393

E-Print Network 3.0 - analysis identifies mode Sample Search...  

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

Summary: , identifying the causes of an identified failure mode is another benefit of FMEA analysis. When consistently... consequences. C. Identify Causes for a Given Failure...

394

modes are nearly completely restored after ther-mal treatment. Similarly, electronic transitions in  

E-Print Network [OSTI]

modes are nearly completely restored after ther- mal treatment. Similarly, electronic transitions, 338 (2003). 13. D. Chattopadhyay, I. Galeska, F. Papadimitrakopoulos, J. Am. Chem. Soc. 125, 3370

Stüwe, Jogy

395

Design and Analysis of a Mach 3 Dual Mode Scramjet Combustor.  

E-Print Network [OSTI]

??Low speed operation of a dual mode scramjet engine is important to the development of a two stage to orbit reusable launch vehicle. This study (more)

Corbin, Christopher Ryan

2008-01-01T23:59:59.000Z

396

SOLVING THE MODE IDENTIFICATION PROBLEM IN ASTEROSEISMOLOGY OF F STARS OBSERVED WITH KEPLER  

SciTech Connect (OSTI)

Asteroseismology of F-type stars has been hindered by an ambiguity in identification of their oscillation modes. The regular mode pattern that makes this task trivial in cooler stars is masked by increased line widths. The absolute mode frequencies, encapsulated in the asteroseismic variable {epsilon}, can help solve this impasse because the values of {epsilon} implied by the two possible mode identifications are distinct. We find that the correct {epsilon} can be deduced from the effective temperature and the line widths and we apply these methods to a sample of solar-like oscillators observed with Kepler.

White, Timothy R.; Bedding, Timothy R.; Benomar, Othman; Stello, Dennis; Huber, Daniel [Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, NSW 2006 (Australia); Gruberbauer, Michael [Institute for Computational Astrophysics, Department of Astronomy and Physics, Saint Mary's University, Halifax, NS B3H 3C3 (Canada); Appourchaux, Thierry [Universite Paris-Sud, Institut d'Astrophysique Spatiale, UMR8617, CNRS, Batiment 121, 91405 Orsay Cedex (France); Chaplin, William J.; Elsworth, Yvonne P.; Hekker, Saskia [School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT (United Kingdom); Christensen-Dalsgaard, Jorgen; Kjeldsen, Hans [Danish AsteroSeismology Centre (DASC), Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Garcia, Rafael A. [Laboratoire AIM, CEA/DSM-CNRS, Universite Paris 7 Diderot, IRFU/SAp, Centre de Saclay, 91191 Gif-sur-Yvette (France); Mosser, Benoit [LESIA, CNRS, Universite Pierre et Marie Curie, Universite Denis Diderot, Observatoire de Paris, 92195 Meudon Cedex (France); Kinemuchi, Karen; Still, Martin [Bay Area Environmental Research Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Mullally, Fergal, E-mail: t.white@physics.usyd.edu.au [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States)

2012-06-01T23:59:59.000Z

397

Higher Order Modes HOM___s in Coupled Cavities of the Flash Module ACC39  

SciTech Connect (OSTI)

We analyse the higher order modes (HOM's) in the 3.9GHz bunch shaping cavities installed in the FLASH facility at DESY. A suite of finite element computer codes (including HFSS and ACE3P) and globalised scattering matrix calculations (GSM) are used to investigate the modes in these cavities. This study is primarily focused on the dipole component of the multiband expansion of the wakefield, with the emphasis being on the development of a HOM-based BPM system for ACC39. Coupled inter-cavity modes are simulated together with a limited band of trapped modes.

Shinton, I.R.R.; /Manchester U. /Cockcroft Inst. Accel. Sci. Tech.; Jones, R.M.; /Manchester U. /DESY; Li, Z.; /SLAC; Zhang, P.; /Manchester U. /Cockcroft Inst. Accel. Sci. Tech. /DESY

2012-09-14T23:59:59.000Z

398

E-Print Network 3.0 - applying failure mode Sample Search Results  

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

the failure mode space of aerospace ... Source: Stone, Robert B. - School of Mechanical, Industrial, and Manufacturing Engineering, Oregon State University Collection: Engineering...

399

Progress In Understanding The Enhanced Petestal H-mode In NSTX  

SciTech Connect (OSTI)

ThIS paper describes the enhanced pedestal (EP) H-mode observed in the National Spherical Torus Experiment (NSTX). The defining characteristics of EP H-mode are given, namely i)transition after the L- to H-mode transition, ii) region of very steep ion temperature gradient, and iii) associated region of strong rotational shear. A newly observed long-pulse EP H-mode example shows quiescent behavior for as long as the heating and current drive sources are maintained. Cases are shown where the region of steep ion temperature gradient is located at the very edge, and cases where it is shifted up to 10 cm inward from the plasma edge; these cases are united by a common dependence of the ion temperature gradient on the toroidal rotation frequency shear. EP H-mode examples have been observed across a wide range of q95 and pedestal collisionality. No strong changes in the fluctuation amplitudes have been observed following the eP H-mode transition, and transport analysis indicates that the ion t hermal transport is comparable to or less than anticipated from a simple neoclassical transport model. Cases are shown where EP H-modes were reliably generated, through these low-q95 examples were difficult to sustain. A case where an externally triggered ELM precipitates the transition to EP H-mode is also shown, though an initial experiment designed to trigger EP-H-modes in this fashion was successful.

none,

2014-06-26T23:59:59.000Z

400

Spontaneous Emission -factors in Photonic Crystal Waveguides: Towards Single-Mode LED  

Science Journals Connector (OSTI)

We theoretically study light emission in photonic crystal waveguides and show that remarkably large spontaneous emission rates into the fundamental guided mode (beta factor >95%)...

Lecamp, Guillaume; Sauvan, Christophe; Lalanne, Philippe; Hugonin, Jean-Paul

Note: This page contains sample records for the topic "modes mode fraction" 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

Properties of the cladding modes of an optical fibre excited by refractive-index gratings  

SciTech Connect (OSTI)

The properties of the cladding modes of an optical fibre, excited by photoinduced long-period fibre gratings, were investigated by the near- and far-field methods. It is shown that the cladding modes considered are of the HE{sub 1m} type. A satisfactory agreement between the experimental and calculated distributions of the electromagnetic field of the modes is demonstrated. It was found that the propagation length of a cladding mode in the unperturbed fibre reaches 1 m. (laser applications and other topics in quantum electronics)

Vasil'ev, Sergei A; Dianov, Evgenii M; Medvedkov, O I; Protopopov, V N [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Costantini, D M; Iocco, A; Limberger, H G; Salathe, R-P [Institute of Applied Optics, Swiss Federal Institute of Technology, Lausanne (Switzerland)

1999-01-31T23:59:59.000Z

402

Extraction of design rules from multi-objective design exploration (MODE) using rough set theory  

Science Journals Connector (OSTI)

Multi-objective design exploration (MODE) and its application for design rule extraction are presented. MODE reveals the structure of design space from the trade-off information. The self-organizing map (SOM) is incorporated into MODE as a visual data-mining tool for design space. SOM divides the design space into clusters with specific design features. The sufficient conditions for belonging to a cluster of interest are extracted using rough set theory. The resulting MODE was applied to the multidisciplinary wing design problem, which revealed a cluster of good designs, and we extracted the design rules of such designs successfully.

Shigeru Obayashi

2011-01-01T23:59:59.000Z

403

E-Print Network 3.0 - active mode control Sample Search Results  

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

Summary: simple features have few features active Jan Bredereke: On Preventing FIs which are Shared-Control Mode... On Preventing Telephony Feature Interactions which are...

404

A boundary element solution for a mode conversion study on the edge reflection of Lamb waves  

Science Journals Connector (OSTI)

The boundary element method well known for bulk wave scattering is extended to study the mode conversion phenomena of Lamb waves from a free edge. The elastodynamic interior boundary value problem is formulated as a hybrid boundary integralequation in conjunction with the normal mode expansion technique based on the Lamb wave dispersion equation. The present approach has the potential of easily handling the geometrical complexity of general guided wave scattering with improved computational efficiency due to the advantage of the boundary?type integral method. To check the accuracy of the boundary element program vertical shear wave diffraction due to a circular hole is solved and compared with previous analytical solutions. Edge reflection factors for the multibackscattered modes in a steel plate are satisfied quite well with the principle of energy conservation. In the cases of A0 A1 and S0 incidence the variations of the multireflection factors show similar tendencies to the existing results for glass. It is observed that the reflection of an incident wave becomes close to zero over a certain frequency range seen through energy interaction with other reflected modes and increases again beyond this minimum point due to reverse mode conversion. The reflections of the higher symmetric incident modes S1 and S2 are also investigated. It turns out that S1 mode is an unusual mode which is nearly unaffected by the mode conversion in the Lamb wave edge reflection.

Younho Cho; Joseph L. Rose

1996-01-01T23:59:59.000Z

405

Focused ion beam engineered whispering gallery mode resonators with open cavity structure  

Science Journals Connector (OSTI)

We report the realization of an open cavity whispering gallery mode optical resonator, in which the circulating light traverses a free space gap. We utilize focused ion beam...

Aveline, David C; Baumgartel, Lukas; Ahn, Byungmin; Yu, Nan

2012-01-01T23:59:59.000Z

406

Pressure dependence of tunneling and librational modes of coupled methyl groups in lithium acetate  

Science Journals Connector (OSTI)

The pressure dependence of the tunneling and librational modes of the coupled methyl groups in lithium acetate dihydrate was studied by inelastic neutron scattering...

A. Heidemann; J. Eckert; L. Passell

1987-01-01T23:59:59.000Z

407

Systems acceptance and operability testing for rotary mode core sampling in flammable gas tanks  

SciTech Connect (OSTI)

This document provides instructions for the system acceptance and operability testing of the rotary mode core sampling system, modified for use in flammable gas tanks.

Corbett, J.E., Westinghouse Hanford

1996-07-29T23:59:59.000Z

408

Electron cyclotron heating and current drive using the electron Bernstein modes .  

E-Print Network [OSTI]

??Electron Bernstein waves are a mode of oscillation in a plasma, thought a candidate for providing radiofrequency heating and non-inductive current drive in spherical tokamaks. (more)

McGregor, Duncan Ekundayo

2007-01-01T23:59:59.000Z

409

Nano plasmon polariton modes of a wedge cross section metal waveguide  

Science Journals Connector (OSTI)

Optical plasmon-polariton modes confined in both transverse dimensions to significantly less than a wavelength are exhibited in open waveguides structured as sharp metal wedges. The...

Feigenbaum, Eyal; Orenstein, Meir

2006-01-01T23:59:59.000Z

410

Constraints on Nucleon Decay via Invisible Modes from the Sudbury Neutrino Observatory  

Science Journals Connector (OSTI)

Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to invisible modes, such as n?3?. The analysis was based on a search for ?rays from the deexcitation of the residual nucleus that would result from the disappearance of either a proton or neutron from O16. A limit of ?inv>21029??yr is obtained at 90% confidence for either neutron- or proton-decay modes. This is about an order of magnitude more stringent than previous constraints on invisible proton-decay modes and 400times more stringent than similar neutron modes.

S. N. Ahmed et al. (SNO Collaboration)

2004-03-10T23:59:59.000Z

411

Second-harmonic generation in single-mode and multimode fibers  

Science Journals Connector (OSTI)

We report efficient second-harmonic generation in several commercially available telecommunication-grade single-mode and multimode optical fibers. We have investigated the effect of...

Saifi, M A; Andrejco, M J

1988-01-01T23:59:59.000Z

412

Ultrafast spectroscopy of super high frequency mechanical modes of doubly clamped beams  

SciTech Connect (OSTI)

We use ultrafast pump-probe spectroscopy to study the mechanical vibrations in the time domain of doubly clamped silicon nitride beams. Beams with two different clamping conditions are investigated. Finite element method calculations are performed to analyse the mode spectra of both structures. By calculating the strain integral on the surface of the resonators, we are able to reproduce the effect of the detection mechanism and identify all the measured modes. We show that our spectroscopy technique combined with our modelling tools allow the investigation of several different modes in the super high frequency range (3-30?GHz) and above, bringing more information about the vibration modes of nanomechanical resonators.

Ristow, Oliver; Merklein, Moritz; Grossmann, Martin; Hettich, Mike; Schubert, Martin; Bruchhausen, Axel; Scheer, Elke; Dekorsy, Thomas; Barretto, Elaine C. S., E-mail: elaine.barretto@uni-konstanz.de [Department of Physics and Center of Applied Photonics, University of Konstanz, D-78457 Konstanz (Germany)] [Department of Physics and Center of Applied Photonics, University of Konstanz, D-78457 Konstanz (Germany); Grebing, Jochen; Erbe, Artur [Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion-Beam Physics and Materials Research, D-01328 Dresden (Germany)] [Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion-Beam Physics and Materials Research, D-01328 Dresden (Germany); Mounier, Denis [IMMM, UMR-CNRS 6283, ENSIM, PRES UNAM, Universit du Maine, 72085 Le Mans (France)] [IMMM, UMR-CNRS 6283, ENSIM, PRES UNAM, Universit du Maine, 72085 Le Mans (France); Gusev, Vitalyi [LAUM, UMR-CNRS 6613, PRES UNAM, Universit du Maine, 72085 Le Mans (France)] [LAUM, UMR-CNRS 6613, PRES UNAM, Universit du Maine, 72085 Le Mans (France)

2013-12-02T23:59:59.000Z

413

Use characteristics and mode choice behavior of electric bike users in China  

E-Print Network [OSTI]

electric bikes will also slightly increase demand for automobileelectric bikes are less of a transitional mode between human-powered bikes and full-blown automobile

Cherry, Christopher; Cervero, Robert

2007-01-01T23:59:59.000Z

414

Comfort standards and variation in exceedance for mixed-mode buildings.  

E-Print Network [OSTI]

a lower carbon society. Building Research & Information, 36(ventilated and mixed-mode buildings Part I: Thermalmodeling. Building and Environment, 44(4), 736749.

Brager, Gail; Borgeson, Sam

2010-01-01T23:59:59.000Z

415

Control Strategies for HCCI Mixed-Mode Combustion  

SciTech Connect (OSTI)

Delphi Automotive Systems and ORNL established this CRADA to expand the operational range of Homogenous Charge Compression Ignition (HCCI) mixed-mode combustion for gasoline en-gines. ORNL has extensive experience in the analysis, interpretation, and control of dynamic engine phenomena, and Delphi has extensive knowledge and experience in powertrain compo-nents and subsystems. The partnership of these knowledge bases was important to address criti-cal barriers associated with the realistic implementation of HCCI and enabling clean, efficient operation for the next generation of transportation engines. The foundation of this CRADA was established through the analysis of spark-assisted HCCI data from a single-cylinder research engine. This data was used to (1) establish a conceptual kinetic model to better understand and predict the development of combustion instabilities, (2) develop a low-order model framework suitable for real-time controls, and (3) provide guidance in the initial definition of engine valve strategies for achieving HCCI operation. The next phase focused on the development of a new combustion metric for real-time characterization of the combustion process. Rapid feedback on the state of the combustion process is critical to high-speed decision making for predictive control. Simultaneous to the modeling/analysis studies, Delphi was focused on the development of engine hardware and the engine management system. This included custom Delphi hardware and control systems allowing for flexible control of the valvetrain sys-tem to enable HCCI operation. The final phase of this CRADA included the demonstration of conventional and spark assisted HCCI on the multi-cylinder engine as well as the characterization of combustion instabilities, which govern the operational boundaries of this mode of combustion. ORNL and Delphi maintained strong collaboration throughout this project. Meetings were held on a bi-weekly basis with additional reports, presentation, and meetings as necessary to maintain progress. Delphi provided substantial support through modeling, hardware, data exchange, and technical consultation. This CRADA was also successful at establishing important next steps to further expanding the use of an HCCI engine for improved fuel efficiency and emissions. These topics will be address in a follow-on CRADA. The objectives are: (1) Improve fundamental understanding of the development of combustion instabilities with HCCI operation through modeling and experiments; (2) Develop low-order model and feedback combustion metrics which are well suited to real-time predictive controls; and (3) Construct multi-cylinder engine system with advanced Delphi technologies and charac-terize HCCI behavior to better understand limitations and opportunities for expanded high-efficiency operation.

Wagner, Robert M [ORNL; Edwards, Kevin Dean [ORNL

2010-03-01T23:59:59.000Z

416

Operation of terahertz quantum-cascade lasers at 164 K in pulsed mode and at 117 K in continuous-wave mode.  

SciTech Connect (OSTI)

We report the demonstration of a terahertz quantum-cascade laser that operates up to 164 K in pulsed mode and 117 K in continuous-wave mode at approximately 3.0 THz. The active region was based on a resonant-phonon depopulation scheme and a metal-metal waveguide was used for modal confinement. Copper to copper thermocompression wafer bonding was used to fabricate the waveguide, which displayed improved thermal properties compared to a previous indium-gold bonding method.

Kumar, Sushil (Massachusetts Institute of Technology, Cambridge, MA); Williams, Benjamin S. (Massachusetts Institute of Technology, Cambridge, MA); Hu, Qing (Massachusetts Institute of Technology, Cambridge, MA); Reno, John Louis

2005-04-01T23:59:59.000Z

417

Edge localized mode particle losses from the DIII-D tokamak  

Science Journals Connector (OSTI)

Particle losses associated with edge localized mode(ELM) activity on the DIII-D tokamak [J. Luxon et al. Proceedings of the 11th International Conference on Plasma Physics and Controlled Nuclear Fusion(International Atomic Energy Agency Vienna 1986 Vol. I p. 159] are evaluated quantitatively using density profile data obtained from a Thomson scattering system. It is shown that up to 10% of the total core particle content is lost with each ELM. The particle loss varies inversely with ELM frequency. The temporally averaged ELM particle loss is shown to be about 25% of the total particle loss from the confined region under a wide variety of plasma conditions. Although this ELM loss is a small fraction of the total ion flux it is large compared to the particle input from neutral beam heating. Hence ELM particle losses are sufficient to control the density rise associated with H-modeplasma operation with neutral beam heating. In addition to controlling the average density by enhancing the total ion flow albeit only by 25% it is posited that the ELMs play a role in determining the density profile in the H-mode pedestal region.

G. D. Porter; T. A. Casper; J. M. Moller

2001-01-01T23:59:59.000Z

418

Progress towards top-up mode operations at the Advanced Photon Source  

Science Journals Connector (OSTI)

The Advanced Photon Source (APS) is a 7-GeV third-generation synchrotron radiation source. To provide a more stable beam for users in September 1998 we began commissioning a new operating mode called top-up. In this mode the beam current does not decay but is maintained at a high level using frequent injection while photon shutters are open and photon beams are delivered to users. The exhaustive analysis for top-up safety will be reviewed as well as the hardware and software required for top-up operation. Operational experience so far includes testing aspects of top-up injection delivering beam to X-ray users for a few hours with fractional current stability of 0.001 and routinely providing beam to users by refilling the ring to 100 mA every 12 hours with shutters open. Top-up performance issues encountered are short-lived orbit and emittance transients during the injection event which appear in user experiments as X-ray beam brightness dips. Planned system modifications to reduce these beam transients are described. The main operational issue left for continuous top-up injection will then be sharing the injector system with other operations.

L. Emery; M. Borland

2000-01-01T23:59:59.000Z

419

Power Supply Changes for NSTX Resistive Wall Mode Coils  

SciTech Connect (OSTI)

The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. Prior to 2004, the NSTX power system was feeding twelve (12) circuits in the machine. In 2004 the Resistive Wall Mode (RWM) Coils were installed on the machine to correct error fields. There are six of these coils installed around the machine in the mid-plane. Since these coils need fast and accurate controls, a Switching Power Amplifier (SPA) with three sub-units was procured, installed and commissioned along with other power loop components. Two RWM Coils were connected in series and fed from one SPA sub-unit. After the initial RWM campaign, operational requirements evolved such that each of the RWM coils now requires separate power and control. Hence a second SPA with three sub-units has been procured and installed. The second unit is of improved design and has the controls and power components completely isolated. The existing thyristor rectifier is used as DC Link to both of the Switching Power Amplifiers. The controls for the RWM are integrated into the overall computer control of the DC Power systems for NSTX. This paper describes the design changes in the RWM Power system for NSTX.

Ramakrishnan, S S.

2013-06-28T23:59:59.000Z

420

The pulsation modes, masses and evolution of luminous red giants  

E-Print Network [OSTI]

The period-luminosity sequences and the multiple periods of luminous red giant stars are examined using the OGLE III catalogue of long-period variables in the Large Magellanic Cloud. It is shown that the period ratios in individual multimode stars are systematically different from the ratios of the periods at a given luminosity of different period-luminosity sequences. This leads to the conclusion that the masses of stars at the same luminosity on the different period-luminosity sequences are different. An evolutionary scenario is used to show that the masses of stars on adjacent sequences differ by about 16-26% at a given luminosity, with the shorter period sequence being more massive. The mass is also shown to vary across each sequence by a similar percentage, with the mass increasing to shorter periods. On one sequence, sequence B, the mass distribution is shown to be bimodal. It is shown that the small amplitude variables on sequences A', A and B pulsate in radial and nonradial modes of angular degree l=0...

Wood, P R

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" from the National Library of EnergyBeta (NLEBeta).
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421

Real-time multi-mode neutron multiplicity counter  

DOE Patents [OSTI]

Embodiments are directed to a digital data acquisition method that collects data regarding nuclear fission at high rates and performs real-time preprocessing of large volumes of data into directly useable forms for use in a system that performs non-destructive assaying of nuclear material and assemblies for mass and multiplication of special nuclear material (SNM). Pulses from a multi-detector array are fed in parallel to individual inputs that are tied to individual bits in a digital word. Data is collected by loading a word at the individual bit level in parallel, to reduce the latency associated with current shift-register systems. The word is read at regular intervals, all bits simultaneously, with no manipulation. The word is passed to a number of storage locations for subsequent processing, thereby removing the front-end problem of pulse pileup. The word is used simultaneously in several internal processing schemes that assemble the data in a number of more directly useable forms. The detector includes a multi-mode counter that executes a number of different count algorithms in parallel to determine different attributes of the count data.

Rowland, Mark S; Alvarez, Raymond A

2013-02-26T23:59:59.000Z

422

Performance degradation of Geiger-mode APDs at cryogenic temperatures  

E-Print Network [OSTI]

Two-phase Cryogenic Avalanche Detectors (CRADs) with THGEM multipliers, optically read out with Geiger-mode APDs (GAPDs), were proposed as potential technique for charge recording in rare-event experiments. In this work we report on the degradation of the GAPD performance at cryogenic temperatures revealed in the course of the study of two-phase CRAD in Ar, with combined THGEM/GAPD-matrix multiplier; the GAPDs recorded secondary scintillation photons from the THGEM holes in the Near Infrared. The degradation effect, namely the loss of the GAPD pulse amplitude, depended on the incident X-ray photon flux. The critical counting rate of photoelectrons produced at the 4.4 mm2 GAPD, degrading its performance at 87 K, was estimated as 10000 per second. This effect was shown to result from the considerable increase of the pixel quenching resistor of this CPTA-made GAPD type. Though not affecting low-rate rare-event experiments, the observed effect may impose some limitations on the performance of CRADs with GAPD-base...

Bondar, A; Dolgov, A; Shekhtman, L; Shemyakina, E; Sokolov, A; Breskin, A; Thers, D

2014-01-01T23:59:59.000Z

423

Coupled-mode theory for film-coupled plasmonic nanocubes  

Science Journals Connector (OSTI)

Planar metallic nanoparticles separated by nanoscale distances from a metal film support unique plasmonic resonances useful for controlling a wide range of photodynamic processes. The fundamental resonance of a film-coupled planar nanoparticle arises from a transmission-line mode localized between nanoparticle and film, whose properties can be roughly approximated by closed form expressions similar to those used in patch antenna theory. The insight provided by the analytical expressions, and the potential of achieving similar closed-form expressions for a range of plasmonic phenomenon such as spasing, fluorescence enhancement, and perfect absorbers, motivates a more detailed study of the film-coupled patch. Here, we present an expanded analytical analysis of the plasmonic patch geometry, applying an eigenmode expansion method to arrive at a more accurate description of the field distribution underneath a film-coupled plasmonic nanocube. The fields corresponding to the inhomogeneous Maxwell's equations are expanded in a set of lossless waveguide eigenmodes. Radiation damping and Ohmic losses are then perturbatively taken into account by considering an equivalent surface impedance. We find that radiative loss couples the lossless eigenmodes, leading to discernible features in the scattering spectra of the nanocubes. The method presented can be further applied to the case of point source excitations, in which accounting for all potential eigenmodes becomes essential.

Patrick T. Bowen and David R. Smith

2014-11-03T23:59:59.000Z

424

MEMS Reliability: Infrastructure, Test Structures, Experiments, and Failure Modes  

SciTech Connect (OSTI)

The burgeoning new technology of Micro-Electro-Mechanical Systems (MEMS) shows great promise in the weapons arena. We can now conceive of micro-gyros, micro-surety systems, and micro-navigators that are extremely small and inexpensive. Do we want to use this new technology in critical applications such as nuclear weapons? This question drove us to understand the reliability and failure mechanisms of silicon surface-micromachined MEMS. Development of a testing infrastructure was a crucial step to perform reliability experiments on MEMS devices and will be reported here. In addition, reliability test structures have been designed and characterized. Many experiments were performed to investigate failure modes and specifically those in different environments (humidity, temperature, shock, vibration, and storage). A predictive reliability model for wear of rubbing surfaces in microengines was developed. The root causes of failure for operating and non-operating MEMS are discussed. The major failure mechanism for operating MEMS was wear of the polysilicon rubbing surfaces. Reliability design rules for future MEMS devices are established.

TANNER,DANELLE M.; SMITH,NORMAN F.; IRWIN,LLOYD W.; EATON,WILLIAM P.; HELGESEN,KAREN SUE; CLEMENT,J. JOSEPH; MILLER,WILLIAM M.; MILLER,SAMUEL L.; DUGGER,MICHAEL T.; WALRAVEN,JEREMY A.; PETERSON,KENNETH A.

2000-01-01T23:59:59.000Z

425

Azimuthal Asymmetries and Vibrational Modes in Bubble Pinch-off  

E-Print Network [OSTI]

The pressure-driven inertial collapse of a cylindrical void in an inviscid liquid is an integrable, Hamiltonian system that forms a finite-time singularity as the radius of the void collapses to zero. Here it is shown that when the natural cylindrical symmetry of the void is perturbed azimuthally, the perturbation modes neither grow nor decay, but instead cause constant amplitude vibrations about the leading-order symmetric collapse. Though the amplitudes are frozen in time, they grow relative to the mean radius which is collapsing to zero, eventually overtaking the leading-order symmetric implosion. Including weak viscous dissipation destroys the integrability of the underlying symmetric implosion, and the effect on the stability spectrum is that short-wavelength disturbances are now erased as the implosion proceeds. Introducing a weak rotational flow component to the symmetric implosion dynamics causes the vibrating shapes to spin as the mean radius collapses. The above theoretical scenario is compared to a closely related experimental realization of void implosion: the disconnection of an air bubble from an underwater nozzle. There, the thin neck connecting the bubble to the nozzle implodes primarily radially inward and disconnects. Recent experiments were able to induce vibrations of the neck shape by releasing the bubble from a slot-shaped nozzle. The frequency and amplitude of the observed vibrations are consistent with the theoretical prediction once surface tension effects are taken into account.

Laura E. Schmidt

2011-12-19T23:59:59.000Z

426

Test of molecular mode coupling theory: A first resume  

E-Print Network [OSTI]

We report recent progress on the test of mode coupling theory for molecular liquids (MMCT) for molecules of arbitrary shape. The MMCT equations in the long time limit are solved for supercooled water including all molecular degrees of freedom. In contrast to our earlier treatment of water as a linear molecule, we find that the glass transition temperature $T_c$ is overestimated by the theory as was found in the case of simple liquids. The nonergodicity parameters are calculated from the "full" set of MMCT-equations truncated at $l_{co}=2$. These results are compared $(i)$ with the nonergodicity parameters from MMCT with $l_{co}=2$ in the "dipole" approximation $n=n'=0$ and the diagonalization approximation $n=n'=0$,$l=l'$ and $(ii)$ with the corresponding results from a MD-simulation. This work supports the possibility that a reduction to the most prominent correlators may constitute a valid approximation for solving the MMCT equations for rigid molecules.

C. Theis; F. Sciortino; A. Latz; R. Schilling; P. Tartaglia

2000-03-31T23:59:59.000Z

427

A Search for the Decay Modes B +/- to h +/- tau l  

SciTech Connect (OSTI)

We present a search for the lepton flavor violating decay modes B{sup {+-}} {yields} h{sup {+-}} {tau}{ell} (h = K, {pi}; {ell} = e, {mu}) using the BABAR data sample, which corresponds to 472 million B{bar B} pairs. The search uses events where one B meson is fully reconstructed in one of several hadronic final states. Using the momenta of the reconstructed B, h, and {ell} candidates, we are able to fully determine the {tau} four-momentum. The resulting {tau} candidate mass is our main discriminant against combinatorial background. We see no evidence for B{sup {+-}} {yields} h{sup {+-}} {tau}{ell} decays and set a 90% confidence level upper limit on each branching fraction at the level of a few times 10{sup -5}.

Lees, J.P.

2012-07-20T23:59:59.000Z

428

NONLINEAR DEVELOPMENT OF THE R-MODE INSTABILITY AND THE MAXIMUM ROTATION RATE OF NEUTRON STARS  

SciTech Connect (OSTI)

We describe how the nonlinear development of the R-mode instability of neutron stars influences spin up to millisecond periods via accretion. When nearly resonant interactions of the l = m = 2 R-mode with pairs of 'daughter modes' are included, the R-mode saturates at the lowest amplitude which leads to significant excitation of a pair of modes. The lower bound for this threshold amplitude is proportional to the damping rate of the particular daughter modes that are excited parametrically. We show that if dissipation occurs in a very thin boundary layer at the crust-core boundary, the R-mode saturation amplitude is too large for angular momentum gain from accretion to overcome loss to gravitational radiation. We find that lower dissipation is required to explain spin up to frequencies much higher than 300 Hz. We conjecture that if the transition from the fluid core to the crystalline crust occurs over a distance much longer than 1 cm, then a sharp viscous boundary layer fails to form. In this case, damping is due to shear viscosity dissipation integrated over the entire star. We estimate the lowest parametric instability threshold from first principles. The resulting saturation amplitude is low enough to permit spin up to higher frequencies. The requirement to allow continued spin up imposes an upper bound to the frequencies attained via accretion that plausibly may be about 750 Hz. Within this framework, the R-mode is unstable for all millisecond pulsars, whether accreting or not.

Bondarescu, Ruxandra [Institute for Theoretical Physics, University of Zurich, CH-8057 Zurich (Switzerland); Wasserman, Ira, E-mail: ruxandra@physik.uzh.ch, E-mail: ira@astro.cornell.edu [Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853 (United States)

2013-11-20T23:59:59.000Z

429

Development of magnetohydrodynamic modes during sawteeth in tokamak M.-C. Firpo,1  

E-Print Network [OSTI]

Development of magnetohydrodynamic modes during sawteeth in tokamak plasmas M.-C. Firpo,1 W of the nonlinear destabilization of modes observed in tokamak sawteeth. A special emphasis is put on the nonlinear unchanged on the early nonlinear timescale within the central tokamak region, which supports a partial

Paris-Sud XI, Université de

430

Trapped-particle diocotron modes T. J. Hilsabeck and T. M. O'Neil  

E-Print Network [OSTI]

Trapped-particle diocotron modes T. J. Hilsabeck and T. M. O'Neil Department of Physics, University rate, and eigenmode structure are compared to experimental observation. The modes are excited on a non-neutral plasma column in which classes of trapped and passing particles have been created by the application

California at San Diego, University of

431

HYBRID MODES OF ORGANIZATION Alliances, Joint Ventures, Networks, and other `strange' animals.  

E-Print Network [OSTI]

1 HYBRID MODES OF ORGANIZATION Alliances, Joint Ventures, Networks, and other `strange' animals version: December 2010) halshs-00624291,version1-16Sep2011 #12;2 HYBRID MODES OF ORGANIZATION Alliances of these arrangements, hereafter identified as "hybrids", remains difficult to quantify, they play a major role

Paris-Sud XI, Université de

432

Second-Order Sliding Mode Control for DFIG-Based Wind Turbines  

E-Print Network [OSTI]

Second-Order Sliding Mode Control for DFIG-Based Wind Turbines Fault Ride-Through Capability-based wind turbine using a high-order sliding mode control. Indeed, it has been recently suggested extra mechanical stress on the wind turbine drive train). Simulations using the NREL FAST code on a 1

Brest, Université de

433

Bearing Fault Detection in DFIG-Based Wind Turbines Using the First Intrinsic Mode Function  

E-Print Network [OSTI]

Bearing Fault Detection in DFIG-Based Wind Turbines Using the First Intrinsic Mode Function Y for bearing fault detection in DFIG-based wind turbines. The proposed method uses the first Intrinsic Mode Terms--Wind turbine, Doubly Fed Induction Generator (DFIG), fault detection, bearings, signal processing

Boyer, Edmond

434

An attack on CFB mode encryption as used by OpenPGP  

Science Journals Connector (OSTI)

This paper describes an adaptive chosen-ciphertext attack on the Cipher Feedback (CFB) mode of encryption as used in OpenPGP. In most circumstances it will allow an attacker to determine 16 bits of any block of plaintext with about 215 oracle ... Keywords: OpenPGP, chosen-ciphertext attacks, cipher-feedback mode, encryption

Serge Mister; Robert Zuccherato

2005-08-01T23:59:59.000Z

435

Cryptanalysis of the CFB mode of the DES with a reduced number of rounds  

Science Journals Connector (OSTI)

Three attacks on the DES with a reduced number of rounds in the Cipher Feedback Mode (CFB) are studied, namely a meet in ... compared to the three basic attacks on the CFB mode. In 8-bit CFB and with 8 rounds in ...

Bart Preneel; Marnix Nuttin; Vincent Rijmen

1994-01-01T23:59:59.000Z

436

Tailoring the Lasing Modes in Semiconductor Nanowire Cavities Using Intrinsic Self-Absorption  

E-Print Network [OSTI]

lasing with a high degree of mode selectivity (over 30 nm). The cadmium sulfide (CdS) NW lasing. Modification of semiconductor band structure/bandgap through electric field modulation, elemental doping success in tuning the optical cavity modes through (a) electric field modulation and (b) elemental doping

Xiong, Qihua

437

TM-mode coupling to a Josephson junction S. J. Lewandowski  

E-Print Network [OSTI]

215 TM-mode coupling to a Josephson junction S. J. Lewandowski Instytut Fizyki PAN, 02-668 Warszawa-mode near cut-off are demonstrated to improve Josephson junction coupling to the waveguide. Revue Phys. Appl Sciences and available at http://dx.doi.org/10.1051/rphysap:01985002003021500 #12;216 Fig. 1. - Josephson

Boyer, Edmond

438

The strength of the radial-breathing mode in single-walled carbon nanotubes  

E-Print Network [OSTI]

The strength of the radial-breathing mode in single-walled carbon nanotubes M. Machón , S. Reich of the absolute Raman cross section of the radial breathing mode (RBM) of single-walled carbon nanotubes. We compare our calculations to measurements of the absolute Raman cross section of individual nanotubes

Nabben, Reinhard

439

The dependence on excitation energy of the D-mode in graphite and carbon nanotubes  

E-Print Network [OSTI]

The dependence on excitation energy of the D-mode in graphite and carbon nanotubes C. Thomsen, S of carbon nanotubes as well. The corresponding calculated D-mode shift is shown explicitely in the nanotube is seven times narrower than in graphite as agrees with experiment. Graphite was first

Nabben, Reinhard

440

New Silicon Carbide Schottky-gate Bipolar Mode Field Effect Transistor (SiC SBMFET)  

E-Print Network [OSTI]

New Silicon Carbide Schottky-gate Bipolar Mode Field Effect Transistor (SiC SBMFET) without PN. In this paper, we propose a novel Schottky-gate BMFET (SBMFET) using P- type 4H Silicon-Carbide 13,41, a wide, Silicon Carbide, Field effect transistor, Simulation. I. INTRODUCTION TH E BMFET operates in bipolar mode

Kumar, M. Jagadesh

Note: This page contains sample records for the topic "modes mode fraction" 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

LHCD and ICRF heating experiments in H-mode plasmas on EAST  

SciTech Connect (OSTI)

An ICRF system with power up to 6.0 MW and a LHCD system up to 4MW have been applied for heating and current drive experiments on EAST. Intensive lithium wall coating was intensively used to reduce particle recycling and Hydrogen concentration in Deuterium plasma, which is needed for effective ICRF and LHCD power absorption in high density plasmas. Significant progress has been made with ICRF heating and LHW current drive for realizing the H-mode plasma operation in EAST. In 2010, H-mode was generated and sustained by LHCD alone, where lithium coating and gas puffing launcher mouth were applied to improve the LHCD power coupling and penetration into the core plasmas at high density of H-modes. During the last two experimental campaigns, ICRF Heating experiments were carried out at the fixed frequency of 27MHz, achieving effective ions and electrons heating with the H Minority Heating (H-MH) mode, where electrons are predominantly heated by collisions with high energy minority ions. The H-MH mode gave the best plasma performance, and realized H-mode alone in 2012. Combination of ICRF and LHW power injection generated the H-mode plasmas with various ELMy characteristics. The first successful application of the ICRF Heating in the D (He3) plasma was also achieved. The progress on ICRF heating, LHCD experiments and their application in achieving H-mode operation from last two years will be discussed in this report.

Zhang, X. J.; Zhao, Y. P.; Wan, B. N.; Ding, B. J.; Xu, G. S.; Gong, X. Z.; Li, J. G. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Lin, Y.; Wukitch, S. [MIT Plasma Science and Fusion Center, Cambridge, MA 02139 (United States); Taylor, G. [Princeton Plasma Physics Laboratory (United States); Noterdaeme, J. M. [Max-Planck Institute for Plasma Physics, D-85748, Garching, Germany and University of Gent (Belgium); Braun, F. [Max-Planck Institute for Plasma Physics, D-85748, Garching (Germany); Magne, R.; Litaudon, X. [CEA, IRFM, F-13108 Saint-Paul Lez Durance (France); Kumazawa, R.; Kasahara, H. [National Institute for Fusion Science, Toki (Japan); Collaboration: EAST Team

2014-02-12T23:59:59.000Z

442

STRUCTURE ET DYNAMIOUE DES RESEAUX DETERMINATION OF THE EIGENVECTORS OF SOFT MODES  

E-Print Network [OSTI]

Ble du deplacement des atomes dans le mode ferro- klectrique de KDzP04 a l'aide de la mkthode des dries be dropped, since we shall be dealing with only one optic mode at a time). Fourier transformation gives is proportional to b, u,, where b, is the coherent neutron scattering length for an atom of type K. For a phonon

Paris-Sud XI, Université de

443

PROGRESS IN QUANTIFYING THE EDGE PHYSICS OF H-MODE REGIME IN DIII-D  

SciTech Connect (OSTI)

Edge conditions in DIII-D are being quantified in order to provide insight into the physics of the H-mode regime. Electron temperature is not the key parameter that controls the L-H transition. Gradients of edge temperature and pressure are much more promising candidates for such parameters. The quality of H-mode confinement is strongly correlated with the height of the H-mode pedestal for the pressure. The gradient of the pressure appears to be controlled by MHD modes, in particular by kink-ballooning modes with finite mode number n. For a wide variety of discharges, the width of the barrier is well described with a relationship that is proportional to ({beta}{sub p}{sup ped}){sup 1/2}. An attractive regime of confinement has been discovered which provides steady-state operation with no ELMs, low impurity content and normal H-mode confinement. A coherent edge MHD-mode evidently provides adequate particle transport to control the plasma density and impurity content while permitting the pressure pedestal to remain almost identical to that observed in ELMing discharges.

R.J. GROEBNER; D.R. BAKER; J.A. BOEDO; K.H. BURRELL; T.N. CARLSTROM; R.D. DERANIAN; E.J. DOYLE; J.R. FERRON; P. GOHIL; G.R. MOYER; C.L. RETTIG; T.L. RHODES; D.M. THOMAS; T.H. OSBORNE; W.P. WEST

2000-10-01T23:59:59.000Z

444

Policy on Programme Titles, Learning Outcomes and Courses (Multi-Location, Multi-Mode Programmes)  

E-Print Network [OSTI]

Policy on Programme Titles, Learning Outcomes and Courses (Multi-Location, Multi-Mode Programmes) In June 2012, a Policy on Programme Titles, Learning Outcomes and Courses was implemented. The policy-permissible variation between programmes offered in different locations and modes. The key points of the Policy

Painter, Kevin

445

Northern Hemisphere Modes of Variability and the Timing of Spring in Western North America  

E-Print Network [OSTI]

by controlling the number and intensity of warm days. There is also a regionwide trend in spring advancement to the atmosphere via carbon and water cycling (Schwartz 1992). Both phenoclimatic indicators (indices based in the biological world may be organized by certain modes of climate variability. If the state of these modes can

446

Energy of the soliton internal modes and broken symmetries in nonlinear optics  

E-Print Network [OSTI]

Energy of the soliton internal modes and broken symmetries in nonlinear optics Dmitry V. Skryabin, in particular, of the negative energy of the internal modes are described in the context of nonlinear optics manuscript received October 3, 2001; accepted October 7, 2001 Applications of the concepts of the energy and

Skryabin, Dmitry

447

Simulations of solar cell absorption enhancement using resonant modes of a nanosphere array  

E-Print Network [OSTI]

Simulations of solar cell absorption enhancement using resonant modes of a nanosphere array an approach for enhancing the absorption of thin-film amorphous silicon solar cells using periodic on the temporal coupled mode theory. Keywords: Resonant Dielectric Structures, Solar cells, Nanospheres

Grandidier, Jonathan

448

Failure Mode and Effect Analysis of Concrete Ties in orth America  

E-Print Network [OSTI]

Engineering University of Illinois at Urbana-Champaign Summary: A failure mode and effect analysis (FMEA in systems and components is the Failure Mode and Effect Analysis (FMEA), and we are applying this approach of concrete ties to take full advantage of their potential. FMEA is an efficient procedure for organizing

Barkan, Christopher P.L.

449

Routes to interchange mode turbulence and chaos in plasmas confined by a helical magnetic field  

E-Print Network [OSTI]

. The helical magnetic field lines introduce a periodicity condition for the flute modes in the verticalRoutes to interchange mode turbulence and chaos in plasmas confined by a helical magnetic field K in a laboratory plasma confined by a helical magnetic field [1], i.e. a toroidal plasma with a weak vertical

450

Excitonic effects on radial breathing mode intensity of single wall carbon nanotubes  

E-Print Network [OSTI]

Excitonic effects on radial breathing mode intensity of single wall carbon nanotubes Kentaro Satoa Abstract We develop exciton-photon and exciton-phonon interaction matrix elements for sin- gle wall carbon- culate resonance Raman intensity for radial breathing mode as a function of diameter and chiral angle

Maruyama, Shigeo

451

All-Fiber Pulsed Lasers Passively Mode-Locked by Transferable Vertically Aligned Carbon Nanotube Film  

E-Print Network [OSTI]

All-Fiber Pulsed Lasers Passively Mode-Locked by Transferable Vertically Aligned Carbon Nanotube of Tokyo, Tokyo 113-8656, Japan An all-fiber passive laser mode locking is realized with a vertically aligned single-walled carbon nanotube film that can be transferred onto an arbitrary substrate using only

Maruyama, Shigeo

452

Passively harmonic mode locked erbium doped fiber soliton laser with carbon nanotubes based  

E-Print Network [OSTI]

Passively harmonic mode locked erbium doped fiber soliton laser with carbon nanotubes based. Tokumoto, H. Kataura, and Y. Achiba, "Sub-200-fs pulsed erbium- doped fiber laser using a carbon nanotube fs erbium-doped fiber laser mode locked with a cellulose polymer film containing single-wall carbon

Turitsyn, Sergei K.

453

Mode-Locked Fiber Lasers Using Adjustable Saturable Absorption in Vertically Aligned Carbon Nanotubes  

E-Print Network [OSTI]

Mode-Locked Fiber Lasers Using Adjustable Saturable Absorption in Vertically Aligned Carbon, carbon nanotube Passively mode-locked fiber lasers have been used in many applications in various fields or the cleaved fiber end.5) In these studies, we used single-walled carbon nanotubes (SWNTs) whose axial

Maruyama, Shigeo

454

High-Order Sliding Mode Control of a DFIG-Based Wind Turbine  

E-Print Network [OSTI]

High-Order Sliding Mode Control of a DFIG-Based Wind Turbine for Power Maximization and Grid Fault have several advantages over the traditional wind turbine operating methods, such as the reduction = Doubly-Fed Induction Generator; WT = Wind Turbine; HOSM = High-Order Sliding Mode; MPPT = Maximum Power

Paris-Sud XI, Université de

455

Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings  

E-Print Network [OSTI]

. The nature of gas-sensing applications requires single- mode operation and good tunability. One wayMode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings July 2006 In this letter, we demonstrate a method of tuning quantum cascade QC lasers by modifying

Arnold, Craig B.

456

DFIG Driven Wind Turbine Grid Fault-Tolerance Using High-Order Sliding Mode Control  

E-Print Network [OSTI]

DFIG Driven Wind Turbine Grid Fault-Tolerance Using High-Order Sliding Mode Control Mohamed (DFIG), control, second-order sliding mode, grid fault-tolerance. Nomenclature WT = Wind Turbine; DFIG increased currents, which may lead to converter failure. Achieving ride-through requirement for DFIG

Boyer, Edmond

457

Observation of a second soundlike mode in superfluid?filled aerogel  

Science Journals Connector (OSTI)

Superfluid 4 He is interesting acoustically because it can support more than one mode of sound propagation and these modes may be used in combination to determine the critical properties of the superfluid. Recently there has been considerable interest in the critical behavior of superfluid 4 He in the presence of a random potential field provided by highly porous media specifically silica aerogels whose porosities exceed 90%. Unlike other porous media where the normal fluid is clamped to the rigid matrix these aerogels are highly compliant and while the normal fluid remains locked to the aerogel matrix both the matrix and the normal fluid can move in response to mechanical and thermal gradients. Therefore one would not observe ordinary fourth sound but rather a sound mode intermediate between first and fourth sound. In addition the superfluid can move in a direction opposite to the normal fluid/aerogel matrix resulting in a second soundlike mode. The first experimental observation of this second soundlike mode in superfluid?filled aerogel is reported and it is shown that it remains a high?quality mode near the critical temperature. Also presented are measurements of the sound mode intermediate between first and fourth sound and a theoretical model that gives good agreement with the observed new sound modes. [Work supported by NSF Grant DMR 9000549 and the Office of Naval Research.

M. J. McKenna; Tania Slawecki; J. D. Maynard

1991-01-01T23:59:59.000Z

458

Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems  

E-Print Network [OSTI]

Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems B. Beltran, T. Ahmed power generation in variable speed wind energy conversion systems (VS-WECS). These systems have two variations. Index Terms--Wind energy conversion system, power generation control, sliding mode control

Boyer, Edmond

459

Mode conversion between Alfvn and slow waves observed in the magnetotail by THEMIS  

E-Print Network [OSTI]

an essential role to its dynamics. They can act as an intermediate energy sink or as a carrier to takeMode conversion between Alfvén and slow waves observed in the magnetotail by THEMIS J. Du,1,2 T. L] We present the direct spacecraft observations of wave mode conversion in the magnetotail

California at Berkeley, University of

460

6d (2, 0) Theory and M5 Branes: A KK Mode Approach  

E-Print Network [OSTI]

6d (2, 0) theory on M5 branes is investigated by considering its KK modes on a 2d space. Selecting KK modes on different 2d spaces amounts to choosing different set of selfdual strings as the perturbative degrees of freedom thus will give the 6d...

Hu, Shan

2013-07-16T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

Generation of communication schedules for multi-mode distributed real-time applications  

Science Journals Connector (OSTI)

A key problem in designing multi-mode real-time systems is the generation of schedules to reduce the complexities of transforming the model semantics to code. Moreover, distributed multi-mode applications are prone to suffer from delays incurred during ...

Akramul Azim; Gonzalo Carvajal; Rodolfo Pellizzoni; Sebastian Fischmeister

2014-03-01T23:59:59.000Z

462

Improved spatial resolution for reflection mode infrared microscopy Hans A. Bechtel,1  

E-Print Network [OSTI]

illumination of the secondary mirror, as is the case with transmission mode. The PSF of a Schwarzschild December 2009 Standard commercial infrared microscopes operating in reflection mode use a mirror to direct the reflected light from the sample to the detector. This mirror blocks about half of the incident light

Martin, Michael C.

463

Monte Carlo simulations of alternative sky observation modes with the Cherenkov Telescope Array  

E-Print Network [OSTI]

We investigate possible sky survey modes with the Middle Sized Telescopes (MST, aimed at covering the energy range from $\\sim$100 GeV to 10 TeV) subsystem of the Cherenkov Telescope Array (CTA). We use the standard CTA tools, CORSIKA and sim_telarray, to simulate the development of gamma-ray showers, proton background and the telescope response. We perform simulations for the H.E.S.S.-site in Namibia, which is one of the candidate sites for the CTA experiment. We study two previously considered modes, parallel and divergent, and we propose a new, convergent mode with telescopes tilted toward the array center. For each mode we provide performance parameters crucial for choosing the most efficient survey strategy. For the non-parallel modes we study the dependence on the telescope offset angle. We show that use of both the divergent and convergent modes results in potential advantages in comparison with use of the parallel mode. The fastest source detection can be achieved in the divergent mode with larger offs...

Szanecki, M; Nied?wiecki, A; Sitarek, J; Bednarek, W

2015-01-01T23:59:59.000Z

464

Multi-mode Damage Detection Methods with Piezoelectric Wafer Active Sensors  

E-Print Network [OSTI]

modes structural health monitoring (SHM) and non- destructive evaluation (NDE) simply by changing the driving frequencies. This paper presents research results obtained by using PWAS transducer for SHM/NDE impedance measurements; (3) PWAS ultrasonic SHM/NDE; and (4) PWAS multi-mode corrosion detection

Giurgiutiu, Victor

465

The influence of grain boundaries on the fracture mode of Zirconium and Zircaloy-2  

Science Journals Connector (OSTI)

The mode of fracture was examined in Zircaloy-2 sheet specimens pulled in tension over a range of strain rates (10?5?10?1 min?1) at 350C. As the strain rate decreased from 10?1 to 10?4 min?1, the mode of fractur...

D. Lee; E. F. Koch; H. C. Rogers

1970-11-01T23:59:59.000Z

466

External Stimulation of Edge Modes Alan Binus, Willy Burke, Ambrogio Fasoli, Theodore  

E-Print Network [OSTI]

to couple power from (most likely) higher-frequency drives (e.g. beating ICRF antennas, amplitude-shifted mode frequency, k Variable frequency desirable: allows robust techniques for resonance ID, overcomes uncertainty in mode frequency, allows to map spectra "Two-color": desirable to drive weakly at off

Princeton Plasma Physics Laboratory

467

Standby and off-mode power demand of new appliances in the Anbal de Almeida  

E-Print Network [OSTI]

of products. With the 1 W standby initiative of the International Energy Agency (IEA), several low power mode consumption are reviewed. hal-00770133,version1-4Jan2013 Author manuscript, published in "6th International and off-mode energy consumption is illustrated by the fact that the IEA estimates that, even

Paris-Sud XI, Université de

468

Two--mode optical tomograms: a possible experimental check of the Robertson uncertainty relations  

E-Print Network [OSTI]

The experimental check of two--mode Robertson uncertainty relations and inequalities for highest quadrature moments is suggested by using homodyne photon detection. The relation between optical tomograms and symplectic tomograms is used to connect the tomographic dispersion matrix and the quadrature components dispersion matrix of the two--mode field states.

V. I. Man'ko; G. Marmo; A. Simoni; F. Ventriglia

2012-02-02T23:59:59.000Z

469

Coupled-Oscillator Arrays for Millimeter-Wave Power-Combining and Mode-Locking  

E-Print Network [OSTI]

. 1. INTRODUCTION Obtaining useful levels of power from solid-state millimeter- wave systems trains of high-energy pulses. This new operation is based on a mode- locking technique similarIF1 P-1 Coupled-Oscillator Arrays for Millimeter-Wave Power-Combining and Mode-Locking Robert A

York, Robert A.

470

Simulation Model of Common-Mode Chokes for High-Power Applications  

E-Print Network [OSTI]

Simulation Model of Common-Mode Chokes for High-Power Applications A. Muetze C. R. Sullivan Found;Simulation Model of Common-Mode Chokes for High-Power Applications Charles R. Sullivan Annette Muetze Thayer simulation models for nanocrystalline cores, and compare the results to experimental measurements. We also

471

Rayleigh-Taylor instability and resulting failure modes of ablatively imploded inertial-fusion targets  

SciTech Connect (OSTI)

This article presents a theory of these instabilities and potential modes of failure caused by them. Discussions are given for the following: small amplitude growth of the outside surface instability; and modes of failure resulting from nonlinear development of the inside surface instability.

Montierth, L.; Morse, R.

1983-04-15T23:59:59.000Z

472

Performance-Energy Tradeoffs for Matrix Multiplication on FPGA-Based Mixed-Mode Chip Multiprocessors  

E-Print Network [OSTI]

1 Performance-Energy Tradeoffs for Matrix Multiplication on FPGA-Based Mixed-Mode Chip presents our performance and energy study on an in-house developed FPGA- based mixed-mode chip approach in microprocessor design. With ever increasing concerns for energy consumption, performance

Ziavras, Sotirios G.

473

Treatment of Pionic Modes at the Nuclear Surface for Transport Descriptions  

E-Print Network [OSTI]

Dispersion relations and amplitudes of collective pionic modes are derived in a pi + nucleon-hole + delta-hole model for use in transport descriptions by means of a local density approximation. It is discussed how pionic modes can be converted to real particles when penetrating the nuclear surface and how earlier treatments can be improved. When the surface is stationary only free pions emerge. The time-dependent situation is also addressed, as is the conversion of non-physical (i.e. unperturbed delta-hole) modes to real particles when the nuclear density vanishes. A simplified one-dimensional scenario is used to investigate the reflection and transmission of pionic modes at the nuclear surface. It is found that reflection of pionic modes is rather unlikely, but the process can be incorporated into transport descriptions by the use of approximate local transmission coefficients.

J. Helgesson; J. Randrup

1995-08-22T23:59:59.000Z

474

Nonlinear evolution of the resistive interchange mode in the cylindrical spheromak  

Science Journals Connector (OSTI)

Results are presented of a study of various aspects of the single helicity nonlinear development of the resistive interchange mode in the cylindrical spheromak. A formulation of the helically symmetric resistive magnetohydrodynamic (MHD) equations that partially separates the ideal MHD characteristics is developed. Mode saturation can occur because of the quasilinear flattening of the pressure profile in the vicinity of the mode rational surface. However this saturation process is defeated when the plasma overheats and in regions of the plasma where the shear is low. Finite fluid compression has significant and optimistic consequences on the long?term nonlinear behavior of this mode. For a tearing mode stable cylindrical spheromak equilibrium configuration with an axial beta value of 6% complete overlap of the m=1 islands occurs in about 3% of the resistive skin time for a magnetic Reynolds number of S=105. For typical parameters of the S?1 device at Princeton this time corresponds to nearly one millisecond.

J. DeLucia; S. C. Jardin

1984-01-01T23:59:59.000Z

475

The Fundamental Multi-Baseline Mode-Mixing Foreground in 21 cm EoR Observations  

E-Print Network [OSTI]

The primary challenge for experiments measuring the neutral hydrogen power spectrum from the Epoch of Reionization (EoR) are mode-mixing effects where foregrounds from very bright astrophysical sources interact with the instrument to contaminate the EoR signal. In this paper we identify a new type of mode-mixing that occurs when measurements from non-identical baselines are combined for increased power spectrum sensitivity. This multi-baseline effect dominates the mode-mixing power and can contaminate the EoR window, an area in Fourier space previously identified to be relatively free of foreground power. Multi-baseline mode-mixing introduces characteristic shapes into the three dimensional Fourier space that are determined by the instrumental configuration and we develop an iterative approach to identifying and removing mode-mixed power based on these instrumental shapes.

Hazelton, Bryna J; Sullivan, Ian S

2013-01-01T23:59:59.000Z

476

Surveillance and diagnostics of the beam mode vibrations of the Ringhals PWRs  

SciTech Connect (OSTI)

Surveillance of core barrel vibrations has been performed in the Swedish Ringhals PWRs for several years. This surveillance is focused mainly on the pendular motion of the core barrel, which is known as the beam mode. The monitoring of the beam mode has suggested that its amplitude increases along the cycle and decreases after refuelling. In the last 5 years several measurements have been taken in order to understand this behaviour. Besides, a non-linear fitting procedure has been implemented in order to better distinguish the different components of vibration. By using this fitting procedure, two modes of vibration have been identified in the frequency range of the beam mode. Several results coming from the trend analysis performed during these years indicate that one of the modes is due to the core barrel motion itself and the other is due to the individual flow induced vibrations of the fuel elements. In this work, the latest results of this monitoring are presented. (authors)

Martin, C. M. [Applied Physics to Natural Resources Dept., Technical Univ. of Madrid UPM, Rios Rosas 21, 28003 Madrid (Spain); Pazsit, I. [Dept. of Nuclear Engineering, Chalmers Univ. of Technology, SE-412 96 Goeteborg (Sweden); Nylen, H. [Vattenfall Ringhals AB, S-432 85 Vaeroebacka (Sweden)

2012-07-01T23:59:59.000Z

477

Fast-light enhancement of an optical cavity by polarization mode coupling  

Science Journals Connector (OSTI)

We present an entirely linear all-optical method of cavity scale factor enhancement that relies on mode coupling between the orthogonal polarization modes of a single optical cavity, eliminating the necessity of using an atomic medium to produce the required anomalous dispersion, which decreases the dependence of the scale factor on temperature and increases signal-to-noise ratio by reducing absorption and nonlinear effects. The use of a single cavity results in common mode rejection of the noise and drift that would be present in a system of two coupled cavities. We show that the scale-factor-to-mode-width ratio is increased above unity for this system, and demonstrate tuning of the scale factor by (i) directly varying the polarization mode coupling via rotation of an intracavity half-wave plate, and (ii) coherent control of the cavity reflectance which is achieved simply by varying the incident polarization superposition. These tuning methods allow us to closely approach the critical anomalous dispersion condition and achieve unprecedented enhancements in scale factor and in the scale-factor-to-mode-width ratio. Based on these findings, we propose an adaptation of the traditional optical cavity gyroscope that takes advantage of polarization mode coupling to enhance the gyro scale factor, and demonstrate how the bandwidth of the scale factor enhancement for this gyroscope can be effectively broadened in comparison with fast-light gyroscopes based on atomic media.

David D. Smith; H. Chang; Krishna Myneni; A. T. Rosenberger

2014-05-05T23:59:59.000Z

478

Vibration modes and acoustic noise in a 4-phase switched reluctance motor  

SciTech Connect (OSTI)

Acoustic noise in the switched reluctance motor is caused primarily by the deformation of the stator lamination stack. Acoustic noise is most severe when the periodic excitation of the SRM phases excites a natural vibration mode of the stack. The natural vibration modes and frequencies of a 4-phase, 8/6 switched reluctance motor are examined. Structural finite element analysis is used to compute the natural modes and frequencies. Impulse tests on the stator stack verify the calculations and show which modes are excited. Heuristic arguments are developed to predict the operating conditions that will excite the natural modes. Measurement of vibration while the machine is under load shows which operating conditions excite the natural modes and verifies the predictions. An approximate formula is derived to predict the frequency of the fundamental vibration mode in terms of lamination dimensions and material properties. The formula is validated by comparison with finite element calculations for several laminations, and hence is shown to be useful in design trade-off studies.

Colby, R.S. [United Technologies Research Center, East Hartford, CT (United States); Mottier, F. [Mottier (Francois), West Hartford, CT (United States); Miller, T.J.E. [Univ. of Glasgow (United Kingdom). Dept. of Electronics and Electrical Engineering

1995-12-31T23:59:59.000Z

479

Energy and frequency dependence of the alpha particle redistribution produced by internal kink modes  

SciTech Connect (OSTI)

The redistribution of alpha particles due to internal kink modes is studied. The exact particle trajectories in the total fields, equilibrium plus perturbation, are calculated. The equilibrium has circular cross section and the plasma parameters are similar to those expected in ITER. The alpha particles are initially distributed according to a slowing down distribution function and have energies between 18?keV and 3.5?MeV. The (1, 1), (2, 2), and (2, 1) modes are included and the effect of changing their amplitude and frequency is studied. When only the (1, 1) mode is included, the spreading of high energy (E?1?MeV) alpha particles increases slowly with the energy and mode frequency. At lower energies, the redistribution is more sensitive to the mode frequency and particle energy. When a (2, 1) mode is added, the spreading increases significantly and particles can reach the edge of the plasma. Trapped particles are the most affected and the redistribution parameter can have maxima above 1?MeV, depending on the mode frequency. These results can have important implications for ash removal.

Farengo, R. [Comisin Nacional de Energa Atmica, Centro Atmico Bariloche e Instituto Balseiro, 8400 Bariloche, RN (Argentina); Ferrari, H. E. [Comisin Nacional de Energa Atmica, Centro Atmico Bariloche e Instituto Balseiro, 8400 Bariloche, RN (Argentina); CONICET, 8400 Bariloche, RN (Argentina); Garcia-Martinez, P. L. [CONICET, 8400 Bariloche, RN (Argentina); Firpo, M.-C.; Ettoumi, W. [Laboratoire de Physique des Plasmas, CNRS, Ecole Polytechnique, 91128, Palaiseau cedex (France); Lifschitz, A. F. [Laboratoire d'Optique Appliquee, ENSTA, CNRS, Ecole Polytechnique, 91761 Palaiseau cedex (France)

2014-08-15T23:59:59.000Z

480

Performance Assessment of Single Electrode-Supported Solid Oxide Cells Operating in the Steam Electrolysis Mode  

SciTech Connect (OSTI)

An experimental study is under way to assess the performance of electrode-supported solid-oxide cells operating in the steam electrolysis mode for hydrogen production. Results presented in this paper were obtained from single cells, with an active area of 16 cm{sup 2} per cell. The electrolysis cells are electrode-supported, with yttria-stabilized zirconia (YSZ) electrolytes ({approx}10 {mu}m thick), nickel-YSZ steam/hydrogen electrodes ({approx}1400 {mu}m thick), and modified LSM or LSCF air-side electrodes ({approx}90 {mu}m thick). The purpose of the present study is to document and compare the performance and degradation rates of these cells in the fuel cell mode and in the electrolysis mode under various operating conditions. Initial performance was documented through a series of voltage-current (VI) sweeps and AC impedance spectroscopy measurements. Degradation was determined through long-term testing, first in the fuel cell mode, then in the electrolysis mode. Results generally indicate accelerated degradation rates in the electrolysis mode compared to the fuel cell mode, possibly due to electrode delamination. The paper also includes details of an improved single-cell test apparatus developed specifically for these experiments.

X. Zhang; J. E. O'Brien; R. C. O'Brien; N. Petigny

2011-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "modes mode fraction" 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

Subsidiary-absorption spin-wave-instability processes in yttrium iron garnet thin films: Coupled lateral standing modes, critical modes, and the kink effect  

Science Journals Connector (OSTI)

Subsidiary-absorption butterfly curves of the spin-wave-instability threshold microwave-field-amplitude versus static field H, for an in-plane magnetized 1.1 mm 2.0 mm, 7-?m-thick yttrium iron garnet film rectangle at 9.4 GHz, and with the linearly polarized microwave field perpendicular to the static field H and also in-plane, are found to show significant changes when H is changed from along the long edge to along the short edge of the rectangle. This effect is explained by a theory for the first-order spin-wave-instability threshold in magnetic films, which takes into acocunt the coupled standing spin-wave modes across the lateral dimensions of the film. This theory is a modification of a previous theory, which considered the standing modes across the film cross section only. The theory is able to reproduce the orientation effect found experimentally and give good fits to the butterfly-curve data. In contrast with previous results, it is not necessary to introduce ad hoc spin-wave angle ?K terms into the spin-wave linewidth to obtain these fits. The theory also yields critical-mode wave numbers in the kink region which are in the 5104 cm-1 range, which agree with previous fine-structure and Brillouin light-scattering measurements. A key parameter in the analysis is a mode spacing parameter ??K, which contains a factor of the form sin(2?K)/K, where K is the mode wave number and ?K is the mode in-plane angle relative to H. These dependences are the key to the match with experiment. They are also general, and not limited to the thin-film geometry.

G. Wiese; P. Kabos; C. E. Patton

1995-06-01T23:59:59.000Z

482

Microsoft PowerPoint - ZhouNing_ModeMeter_CERTS 02.pptx  

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

Presenter: Ning Zhou Presenter: Ning Zhou Pacific Northwest National Laboratory ning.zhou@pnnl.gov 27/28 June 2013 Washington, DC DOE/OE Transmission Reliability Program Work Team  PNNL Team - Ning Zhou - Frank Tuffner  The work under this project closely aligns and collaborates with the research under the TRP project "Measurement Based Stability Assessment" being conducted by: - Dan Trudnowski, Montana Tech - John Pierre, University of Wyoming - Louis Scharf, Colorado State University (Retired) - Many graduate students 2 Project Objective: Mode Identification  Problem formulation: - Lightly damped mode => growing oscillations => system breakup => large scale outage - Low confidence in oscillatory modes => conservative

483

Detecting the Amplitude Mode of Strongly Interacting Lattice Bosons by Bragg Scattering  

SciTech Connect (OSTI)

We report the first detection of the Higgs-type amplitude mode using Bragg spectroscopy in a strongly interacting condensate of ultracold atoms in an optical lattice. By the comparison of our experimental data with a spatially resolved, time-dependent bosonic Gutzwiller calculation, we obtain good quantitative agreement. This allows for a clear identification of the amplitude mode, showing that it can be detected with full momentum resolution by going beyond the linear response regime. A systematic shift of the sound and amplitude modes' resonance frequencies due to the finite Bragg beam intensity is observed.

Bissbort, Ulf; Hofstetter, Walter [Institut fuer Theoretische Physik, Johann Wolfgang Goethe-Universitaet, 60438 Frankfurt/Main (Germany); Goetze, Soeren; Heinze, Jannes; Krauser, Jasper S.; Weinberg, Malte; Becker, Christoph; Sengstock, Klaus [Institut fuer Laser-Physik, Universitaet Hamburg, 22761 Hamburg (Germany); Li Yongqiang [Institut fuer Theoretische Physik, Johann Wolfgang Goethe-Universitaet, 60438 Frankfurt/Main (Germany); Department of Physics, National University of Defense Technology, Changsha 410073 (China)

2011-05-20T23:59:59.000Z

484

Symmetric and anti-symmetric buckle propagation modes in subsea corroded pipelines  

Science Journals Connector (OSTI)

Solutions for the steady-state buckle propagation modes and pressures in a corroded pipeline subjected to external hydrostatic pressure are presented. The buckle propagation pressure of a corroded pipeline is obtained analytically with a rigid-plastic analysis and numerically from finite element analysis (ABAQUS). Both the rigid-plastic analysis and ABAQUS program reveal symmetric and anti-symmetric buckling modes, depending on the depth and angular extent of the corrosion. Snap-through and global buckling of the pipeline are also distinguished in both solutions. The rigid-plastic solutions for buckle propagation pressure and corresponding collapse modes are found to be within 15% with numerical solutions.

Jianghong Xue; Michelle S. Hoo Fatt

2005-01-01T23:59:59.000Z

485

Observation of H-Mode Confinement in the DIII-D Tokamak with Electron Cyclotron Heating  

Science Journals Connector (OSTI)

The first observation of H-mode confinement with electron heating as the sole auxiliary heating method has been made in divertor discharges in the DIII-D tokamak. These discharges exhibit the usual characteristics of the H mode, including improved confinement of particles and energy, when electron cyclotron heating is added at a power level above 0.7 MW. The H-mode transition is accompanied by the development of an electron temperature pedestal of 0.25 keV and a dramatic steepening of the density gradient near the separatrix.

John Lohr; B. W. Stallard; R. Prater; R. T. Snider; K. H. Burrell; R. J. Groebner; D. N. Hill; Kyoko Matsuda; C. P. Moeller; T. W. Petrie; H. St. John; T. S. Taylor

1988-06-20T23:59:59.000Z

486

Thermomechanical two-mode squeezing in an ultrahigh $Q$ membrane resonator  

E-Print Network [OSTI]

We realize a nondegenerate parametric amplifier in an ultrahigh $Q$ mechanical membrane resonator and demonstrate two-mode thermomechanical noise squeezing. Our measurements are accurately described by a two-mode model that attributes this nonlinear mechanical interaction to a substrate-mediated process which is dramatically enhanced by the quality factors of the individual modes. This realization of strong multimode nonlinearities in a mechanical platform compatible with quantum-limited optical detection and cooling makes this a powerful system for nonlinear approaches to quantum metrology, transduction between optical and phononic fields and the quantum manipulation of phononic degrees of freedom.

Y. S. Patil; S. Chakram; L. Chang; M. Vengalattore

2014-10-27T23:59:59.000Z

487

Thermomechanical two-mode squeezing in an ultrahigh $Q$ membrane resonator  

E-Print Network [OSTI]

We realize a nondegenerate parametric amplifier in an ultrahigh $Q$ mechanical membrane resonator and demonstrate two-mode thermomechanical noise squeezing. Our measurements are accurately described by a two-mode model that attributes this nonlinear mechanical interaction to a substrate-mediated process which is dramatically enhanced by the quality factors of the individual modes. This realization of strong multimode nonlinearities in a mechanical platform compatible with quantum-limited optical detection and cooling makes this a powerful system for nonlinear approaches to quantum metrology, transduction between optical and phononic fields and the quantum manipulation of phononic degrees of freedom.

Patil, Y S; Chang, L; Vengalattore, M

2014-01-01T23:59:59.000Z

488

An Instability due to the Nonlinear Coupling of p-modes to g-modes: Implications for Coalescing Neutron Star Binaries  

Science Journals Connector (OSTI)

A weakly nonlinear fluid wave propagating within a star can be unstable to three-wave interactions. The resonant parametric instability is a well-known form of three-wave interaction in which a primary wave of frequency ? a excites a pair of secondary waves of frequency ? b + ? c ? a . Here we consider a nonresonant form of three-wave interaction in which a low-frequency primary wave excites a high-frequency p-mode and a low-frequency g-mode such that ? b + ? c ? a . We show that a p-mode can couple so strongly to a g-mode of similar radial wavelength that this type of nonresonant interaction is unstable even if the primary wave amplitude is small. As an application, we analyze the stability of the tide in coalescing neutron star binaries to p-g mode coupling. We find that the equilibrium tide and dynamical tide are both p-g unstable at gravitational wave frequencies f gw 20 Hz and drive short wavelength p-g mode pairs to significant energies on very short timescales (much less than the orbital decay time due to gravitational radiation). Resonant parametric coupling to the tide is, by contrast, either stable or drives modes at a much smaller rate. We do not solve for the saturation of the p-g instability and therefore we cannot say precisely how it influences the evolution of neutron star binaries. However, we show that if even a single daughter mode saturates near its wave breaking amplitude, the p-g instability of the equilibrium tide will (1) induce significant orbital phase errors (? 1 radian) that accumulate primarily at low frequencies (f gw 50 Hz) and (2) heat the neutron star core to a temperature of T ~ 1010 K. Since there are at least ~100 unstable p-g daughter pairs, ? and T are potentially much larger than these values. Tides might therefore significantly influence the gravitational wave signal and electromagnetic emission from coalescing neutron star binaries at much larger orbital separations than previously thought.

Nevin N. Weinberg; Phil Arras; Joshua Burkart

2013-01-01T23:59:59.000Z

489

Modeling of Mode Transition Behavior in Argon Microhollow Cathode Discharges  

E-Print Network [OSTI]

conversion to molecular ions and three-body quenching of excited states become important resulting pressure causes a large fraction of the input power to be dissipated into gas heating. The gas thermal

Raja, Laxminarayan L.

490

A two-port polarization-insensitive coupler module between single-mode fiber and silicon-wire waveguide  

E-Print Network [OSTI]

and C. Tsai, A two-port single- mode fiber silicon wireA two-port polarization-insensitive coupler module betweenAbstract: A two-port polarization-insensitive single-mode

Shiraishi, Kazuo; Yoda, Hidehiko; Tsai, Chen S

2012-01-01T23:59:59.000Z

491

Developing Mode-Rich Satellite Software by Refinement in Event B Alexei Iliasov, Elena Troubitsyna, Linas Laibinis, Alexander Romanovsky, Kimmo  

E-Print Network [OSTI]

an intricate mode-transition scheme. We show that re refinement in Event-B provides the engineers an intricate mode-transition scheme. We show that re refinement in Event-B provides the engineers

Newcastle upon Tyne, University of

492

A PERSPECTIVE ON THE NUMERICAL AND EXPERIMENTAL CHARACTERISTICS OF MULTI-MODE DRY-FRICTION WHIP AND WHIRL  

E-Print Network [OSTI]

of tapered Timoshenko beam finite elements to form multiple degree of freedom rotor and stator models. These models are reduced by component mode synthesis to discard highfrequency modes while retaining physical coordinates at locations for nonlinear...

Wilkes, Jason C.

2010-01-16T23:59:59.000Z

493

Detection of high-energy adsorbate vibrational modes by atom-surface scattering Yarong Tang and J. R. Manson  

E-Print Network [OSTI]

Detection of high-energy adsorbate vibrational modes by atom-surface scattering Yarong Tang and J modes of surface adsorbates can produce very characteristic signature features in the observable the substrate and other low-energy adsorbate modes. Calculations for the scattering of rare gases from several

Manson, Joseph R.

494

22nd IAEA-FEC Kinetic theory of Geodesic Acoustic Modes: ... 1 Kinetic theory of Geodesic Acoustic  

E-Print Network [OSTI]

22nd IAEA-FEC Kinetic theory of Geodesic Acoustic Modes: ... 1 Kinetic theory of Geodesic Acoustic Zonca, Liu Chen and Zhiyong Qiu #12;22nd IAEA-FEC Kinetic theory of Geodesic Acoustic Modes: ... 2 Chen and Zhiyong Qiu #12;22nd IAEA-FEC Kinetic theory of Geodesic Acoustic Modes: ... 3 2 Linear

Zonca, Fulvio

495

Intensities of the Raman-active modes in single and multiwall nanotubes S. Reich and C. Thomsen  

E-Print Network [OSTI]

of recent experiments on aligned nanotubes we calculate the relative intensities for the high-energy modes of the nanotubes and on the excitation energy. As was shown by Milnera et al.3 the radial breathing modeIntensities of the Raman-active modes in single and multiwall nanotubes S. Reich and C. Thomsen

Nabben, Reinhard

496

High-Performance Integrated Dual-Gate AlGaN/GaN Enhancement-Mode Transistor  

E-Print Network [OSTI]

In this letter, we present a new AlGaN/GaN enhancement-mode (E-mode) transistor based on a dual-gate structure. The dual gate allows the transistor to combine an E-mode behavior with low on-resistance and very high breakdown ...

Lu, Bin

497

Mode-I fracture in a nonlinear lattice with viscoelastic forces Shay I. Heizler and David A. Kessler  

E-Print Network [OSTI]

Mode-I fracture in a nonlinear lattice with viscoelastic forces Shay I. Heizler and David A July 2002 We study mode-I fracture in a viscoelastic lattice model with a nonlinear force law force laws in mode-III fracture. At small driving, there is a strong dependency of the velocity curve

Levine, Herbert

498

Transportation Sector Energy Use by Fuel Type Within a Mode from EIA AEO  

Open Energy Info (EERE)

Sector Energy Use by Fuel Type Within a Mode from EIA AEO Sector Energy Use by Fuel Type Within a Mode from EIA AEO 2011 Early Release Dataset Summary Description Supplemental Table 46 of EIA AEO 2011 Early Release Source EIA Date Released December 08th, 2010 (3 years ago) Date Updated Unknown Keywords AEO Annual Energy Outlook EIA Energy Information Administration Fuel mode TEF transportation Transportation Energy Futures Data text/csv icon Transportation_Sector_Energy_Use_by_Fuel_Type_Within_a_Mode.csv (csv, 144.3 KiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Annually Time Period 2008-2035 License License Open Data Commons Public Domain Dedication and Licence (PDDL) Comment Rate this dataset Usefulness of the metadata Average vote Your vote Usefulness of the dataset Average vote Your vote

499

Tackling the Improved Control of Mixed-Mode Buildings: A Research Update  

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

Tackling the Improved Control of Mixed-Mode Buildings: A Research Update Tackling the Improved Control of Mixed-Mode Buildings: A Research Update Speaker(s): Peter May-Ostendorp Date: March 29, 2010 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: William Fisk (This presentation by Peter May-Ostendorp will begin with an introduction to building energy research at UC Boulder, by Prof. Gregor Henze.) Mixed-mode (MM) cooling is a promising building design strategy for low-energy cooling that incorporates natural ventilation alongside other forms of space conditioning. A properly designed system will intelligently switch between modes of cooling to maximize energy savings, while preserving occupant comfort. The near-optimal operation of MM buildings is explored through a model-predictive control (MPC) study using a purpose-built optimization environment coupled to EnergyPlus. Preliminary

500

The slow-mode nature of compressible wave power in solar wind turbulence  

E-Print Network [OSTI]

We use a large, statistical set of measurements from the Wind spacecraft at 1 AU, and supporting synthetic spacecraft data based on kinetic plasma theory, to show that the compressible component of inertial range solar wind turbulence is primarily in the kinetic slow mode. The zero-lag cross correlation C(delta n, delta B_parallel) between proton density fluctuations delta n and the field-aligned (compressible) component of the magnetic field delta B_parallel is negative and close to -1. The typical dependence of C(delta n,delta B_parallel) on the ion plasma beta_i is consistent with a spectrum of compressible wave energy that is almost entirely in the kinetic slow mode. This has important implications for both the nature of the density fluctuation spectrum and for the cascade of kinetic turbulence to short wavelengths, favoring evolution to the kinetic Alfven wave mode rather than the (fast) whistler mode.

Howes, G G; Klein, K G; Chen, C H K; Salem, C S; TenBarge, J M

2011-01-01T23:59:59.000Z