Property:Maximum Wave Height(m) | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid JumpEligSysSize JumpTechDsc Jump to:
Property:Maximum Wave Height(m) at Wave Period(s) | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid JumpEligSysSize JumpTechDsc Jump to: navigation,
Maximum gravitational-wave energy emissible in magnetar flares
Alessandra Corsi; Benjamin J. Owen
2011-02-16T23:59:59.000Z
Recent searches of gravitational-wave (GW) data raise the question of what maximum GW energies could be emitted during gamma-ray flares of highly magnetized neutron stars (magnetars). The highest energies (\\sim 10^{49} erg) predicted so far come from a model [K. Ioka, Mon. Not. Roy. Astron. Soc. 327, 639 (2001)] in which the internal magnetic field of a magnetar experiences a global reconfiguration, changing the hydromagnetic equilibrium structure of the star and tapping the gravitational potential energy without changing the magnetic potential energy. The largest energies in this model assume very special conditions, including a large change in moment of inertia (which was observed in at most one flare), a very high internal magnetic field, and a very soft equation of state. Here we show that energies of 10^{48}-10^{49} erg are possible under more generic conditions by tapping the magnetic energy, and we note that similar energies may also be available through cracking of exotic solid cores. Current observational limits on gravitational waves from magnetar fundamental modes are just reaching these energies and will beat them in the era of advanced interferometers.
Parameterization of Maximum Wave Heights Forced by Hurricanes: Application to Corpus Christi, Texas
Taylor, Sym 1978-
2012-12-07T23:59:59.000Z
sensitivity based on the investigation of several hurricane parameters. Also presented is the development of parameterized maximum significant wave height models. These are determined by incorporating three forms of an equivalent fetch into (1) dimensionless...
LANGMUIR WAVE ACTIVITY: COMPARING THE ULYSSES SOLAR MINIMUM AND SOLAR MAXIMUM ORBITS
California at Berkeley, University of
). The top three panels correspond to the southern segment of the solar minimum orbit; repeated passesLANGMUIR WAVE ACTIVITY: COMPARING THE ULYSSES SOLAR MINIMUM AND SOLAR MAXIMUM ORBITS R. J at the electron plasma frequency) during the solar minimum and solar maximum orbits of Ulysses. At high latitudes
LaCure, Mari Mae
2010-04-29T23:59:59.000Z
Waves is the supporting document to the Master of Fine Arts thesis exhibition of the same title. Exhibited March 7-12 2010 in the Art and Design Gallery at the University of Kansas, Waves was comprised of a series of mixed media drawings...
MELE: Maximum Entropy Leuven Estimators
Paris, Quirino
2001-01-01T23:59:59.000Z
of the Generalized Maximum Entropy Estimator of the Generaland Douglas Miller, Maximum Entropy Econometrics, Wiley andCalifornia Davis MELE: Maximum Entropy Leuven Estimators by
Maximum Parsimony and Maximum Likelihood Methods Comparisons and Bootstrap Tests
Qiu, Weigang
Maximum Parsimony and Maximum Likelihood Methods Comparisons and Bootstrap Tests Character Likelihood Methods Comparisons and Bootstrap Tests Character Reconstruction PHYLIP and T-REX Exercises Outline 1 Maximum Parsimony and Maximum Likelihood 2 Methods Comparisons and Bootstrap Tests 3 Character
Maximum Entropy Correlated Equilibria
Ortiz, Luis E.
2006-03-20T23:59:59.000Z
We study maximum entropy correlated equilibria in (multi-player)games and provide two gradient-based algorithms that are guaranteedto converge to such equilibria. Although we do not provideconvergence rates for these ...
Wave momentum flux parameter: a descriptor for nearshore waves
US Army Corps of Engineers
Wave momentum flux parameter: a descriptor for nearshore waves Steven A. Hughes* US Army Engineer Available online 7 October 2004 Abstract A new parameter representing the maximum depth-integrated wave momentum flux occurring over a wave length is proposed for characterizing the wave contribution
university-logo Maximum likelihood
McCullagh, Peter
university-logo Maximum likelihood Applications and examples REML and residual likelihood Peter McCullagh REML #12;university-logo Maximum likelihood Applications and examples JAN: Some personal remarks... IC #12;university-logo Maximum likelihood Applications and examples Outline 1 Maximum likelihood REML
Achieve maximum application availability and
Bernstein, Phil
Highlights Achieve maximum application availability and data protection using SQL Server AlwaysOn and other high availability features Reduce planned downtime significantly with SQL Server on Windows and management of high availability and disaster recovery using integrated tools Achieve maximum application
Original article Restricted maximum likelihood
Paris-Sud XI, Université de
Original article Restricted maximum likelihood estimation of covariances in sparse linear models on the simplex algorithm of Nelder and Mead [40]. Kovac [29] made modifications that turned it into a stable
Property:Maximum Wave Length(m) | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal PwerPerkins County, Nebraska:PrecourtOid JumpEligSysSize JumpTechDsc Jump to:" Showing 18
NGC2613, 3198, 6503, 7184: Case studies against `maximum' disks
B. Fuchs
1998-12-02T23:59:59.000Z
Decompositions of the rotation curves of NGC2613, 3198, 6505, and 7184 are analysed. For these galaxies the radial velocity dispersions of the stars have been measured and their morphology is clearly discernible. If the parameters of the decompositions are chosen according to the `maximum' disk hypothesis, the Toomre Q stability parameter is systematically less than one and the multiplicities of the spiral arms as expected from density wave theory are inconsitent with the observed morphologies of the galaxies. The apparent Q<1 instability, in particular, is a strong argument against the `maximum' disk hypothesis.
Michael Spillane; Alexander Stoffers; Ismail Zahed
2011-10-23T23:59:59.000Z
We study the propagation of an ultrarelativistic light quark jet inside a shock wave using the holographic principle. The maximum stopping distance and its dependency on the energy of the jet is obtained.
Maximum likelihood estimation for cooperative sequential adsorption
Burton, Geoffrey R.
Maximum likelihood estimation for cooperative sequential adsorption Mathew D. Penrose and Vadim;Maximum likelihood estimation for cooperative sequential adsorption M.D. Penrose, Department of the region. Keywords: cooperative sequential adsorption, space-time point pro- cess, maximum likelihood
Estimating a mixed strategy employing maximum entropy
Golan, Amos; Karp, Larry; Perloff, Jeffrey M.
1996-01-01T23:59:59.000Z
MIXED STRATEGY EMPLOYING MAXIMUM ENTROPY by Amos Golan LarryMixed Strategy Employing Maximum Entropy Amos Golan Larry S.Abstract Generalized maximum entropy may be used to estimate
Weijgaert, Rien van de
;14/03/2014 6 H L H L L Phase & Group Velocity #12;14/03/2014 7 Doppler Effect #12;14/03/2014 8 Shock Waves #12;14/03/2014 14 Supernova Remnant Cassiopeia A Supernova blast waves #12;14/03/2014 15 Tycho's Remnant (SN 1572AD A SNR flythrough Theory of Supernova Blast Waves Supernovae: Type Ia Subsonic deflagration wave turning
Boiler Maximum Achievable Control Technology (MACT) Technical...
Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact Sheet, April 2015 Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact...
Numerical modeling of extreme rogue waves generated by directional energy focusing
Grilli, StÃ©phan T.
of an overturning rogue wave, and analyze the sensitivity of its geometry and kinematics to water depth and maximum. Keywords: Water waves; Numerical wave tank; Extreme wave kinematics; Rogue waves 1. Introduction finely resolved 3D focused overturning waves and analyze their geometry and kinematics. In this paper, we
Maximum entropy principal for transportation
Bilich, F. [University of Brasilia (Brazil); Da Silva, R. [National Research Council (Brazil)
2008-11-06T23:59:59.000Z
In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.
Geddes, Cameron Guy Robinson
Warm wave breaking of nonlinear plasma waves with arbitrary phase velocities C. B. Schroeder, E, collisionless plasma is developed to analyze nonlinear plasma waves excited by intense drive beams. The maximum amplitude and wavelength are calculated for nonrelativistic plasma temperatures and arbitrary plasma wave
Optimization Online - Efficient Heuristic Algorithms for Maximum ...
T. G. J. Myklebust
2012-11-19T23:59:59.000Z
Nov 19, 2012 ... Efficient Heuristic Algorithms for Maximum Utility Product Pricing Problems. T. G. J. Myklebust(tmyklebu ***at*** csclub.uwaterloo.ca)
Mandelis, Andreas
Photothermoacoustic imaging of biological tissues: maximum depth characterization comparison for Advanced Diffusion-Wave Technologies Department of Mechanical and Industrial Engineering 5 King's College induced in light-absorbing materials can be observed either as a transient signal in time domain
Maximum entropy segmentation of broadcast news
Christensen, Heidi; Kolluru, BalaKrishna; Gotoh, Yoshihiko; Renals, Steve
2005-01-01T23:59:59.000Z
speech recognizer and subsequently segmenting the text into utterances and topics. A maximum entropy approach is used to build statistical models for both utterance and topic segmentation. The experimental work addresses the effect on performance...
Cell development obeys maximum Fisher information
B. R. Frieden; R. A. Gatenby
2014-04-29T23:59:59.000Z
Eukaryotic cell development has been optimized by natural selection to obey maximal intracellular flux of messenger proteins. This, in turn, implies maximum Fisher information on angular position about a target nuclear pore complex (NPR). The cell is simply modeled as spherical, with cell membrane (CM) diameter 10 micron and concentric nuclear membrane (NM) diameter 6 micron. The NM contains about 3000 nuclear pore complexes (NPCs). Development requires messenger ligands to travel from the CM-NPC-DNA target binding sites. Ligands acquire negative charge by phosphorylation, passing through the cytoplasm over Newtonian trajectories toward positively charged NPCs (utilizing positive nuclear localization sequences). The CM-NPC channel obeys maximized mean protein flux F and Fisher information I at the NPC, with first-order delta I = 0 and approximate 2nd-order delta I = 0 stability to environmental perturbations. Many of its predictions are confirmed, including the dominance of protein pathways of from 1-4 proteins, a 4nm size for the EGFR protein and the approximate flux value F =10^16 proteins/m2-s. After entering the nucleus, each protein ultimately delivers its ligand information to a DNA target site with maximum probability, i.e. maximum Kullback-Liebler entropy HKL. In a smoothness limit HKL approaches IDNA/2, so that the total CM-NPC-DNA channel obeys maximum Fisher I. Thus maximum information approaches non-equilibrium, one condition for life.
Maximum Likelihood Haplotyping for General Pedigrees
Friedman, Nir
networks. The use of Bayesian networks enables efficient maximum likelihood haplotyping for more complex for the variables of the Bayesian network. The presented optimization algorithm also improves likelihood Analysis, Pedigree, superlink. Abstract Haplotype data is valuable in mapping disease-susceptibility genes
Weak Scale From the Maximum Entropy Principle
Yuta Hamada; Hikaru Kawai; Kiyoharu Kawana
2014-09-23T23:59:59.000Z
The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\\cal{O}}(300\\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \\begin{equation} v_{h}\\sim\\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\
Weak Scale From the Maximum Entropy Principle
Hamada, Yuta; Kawana, Kiyoharu
2014-01-01T23:59:59.000Z
The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\\cal{O}}(300\\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \\begin{equation} v_{h}\\sim\\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\
Integrating Correlated Bayesian Networks Using Maximum Entropy
Jarman, Kenneth D.; Whitney, Paul D.
2011-08-30T23:59:59.000Z
We consider the problem of generating a joint distribution for a pair of Bayesian networks that preserves the multivariate marginal distribution of each network and satisfies prescribed correlation between pairs of nodes taken from both networks. We derive the maximum entropy distribution for any pair of multivariate random vectors and prescribed correlations and demonstrate numerical results for an example integration of Bayesian networks.
Paul S. Wesson
2012-12-11T23:59:59.000Z
As an example of the unification of gravitation and particle physics, an exact solution of the five-dimensional field equations is studied which describes waves in the classical Einstein vacuum. While the solution is essentially 5D in nature, the waves exist in ordinary 3D space, and may provide a way to test for an extra dimension.
QCD Level Density from Maximum Entropy Method
Shinji Ejiri; Tetsuo Hatsuda
2005-09-24T23:59:59.000Z
We propose a method to calculate the QCD level density directly from the thermodynamic quantities obtained by lattice QCD simulations with the use of the maximum entropy method (MEM). Understanding QCD thermodynamics from QCD spectral properties has its own importance. Also it has a close connection to phenomenological analyses of the lattice data as well as experimental data on the basis of hadronic resonances. Our feasibility study shows that the MEM can provide a useful tool to study QCD level density.
Tissue Radiation Response with Maximum Tsallis Entropy
Sotolongo-Grau, O.; Rodriguez-Perez, D.; Antoranz, J. C.; Sotolongo-Costa, Oscar [UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain); UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain) and University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba); University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba)
2010-10-08T23:59:59.000Z
The expression of survival factors for radiation damaged cells is currently based on probabilistic assumptions and experimentally fitted for each tumor, radiation, and conditions. Here, we show how the simplest of these radiobiological models can be derived from the maximum entropy principle of the classical Boltzmann-Gibbs expression. We extend this derivation using the Tsallis entropy and a cutoff hypothesis, motivated by clinical observations. The obtained expression shows a remarkable agreement with the experimental data found in the literature.
A global maximum power point tracking DC-DC converter
Duncan, Joseph, 1981-
2005-01-01T23:59:59.000Z
This thesis describes the design, and validation of a maximum power point tracking DC-DC converter capable of following the true global maximum power point in the presence of other local maximum. It does this without the ...
articulatorily constrained maximum: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
weight spanning forests. Amitabha Bagchi; Ankur Bhargava; Torsten Suel 2005-01-01 27 Maximum Entropy Correlated Equilibria MIT - DSpace Summary: We study maximum entropy...
The parametric decay of Alfven waves into shear Alfven waves and dust lower hybrid waves
Jamil, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Department of Physics, Crescent Model School Shadman, Lahore 54000 (Pakistan); Shah, H. A.; Zubia, K.; Zeba, I.; Uzma, Ch. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salimullah, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Department of Physics, Jahangirnagar University, Savar, Dhaka 1342 (Bangladesh)
2010-07-15T23:59:59.000Z
The parametric decay instability of Alfven wave into low-frequency electrostatic dust-lower-hybrid and electromagnetic shear Alfven waves has been investigated in detail in a dusty plasma in the presence of external/ambient uniform magnetic field. Magnetohydrodynamic fluid equations of plasmas have been employed to find the linear and nonlinear response of the plasma particles for this three-wave nonlinear coupling in a dusty magnetoplasma. Here, relatively high frequency electromagnetic Alfven wave has been taken as the pump wave. It couples with other two low-frequency internal possible modes of the dusty magnetoplasma, viz., the dust-lower-hybrid and shear Alfven waves. The nonlinear dispersion relation of the dust-lower-hybrid wave has been solved to obtain the growth rate of the parametric decay instability. The growth rate is maximum for small value of external magnetic field B{sub s}. It is noticed that the growth rate is proportional to the unperturbed electron number density n{sub oe}.
Conductivity maximum in a charged colloidal suspension
Bastea, S
2009-01-27T23:59:59.000Z
Molecular dynamics simulations of a charged colloidal suspension in the salt-free regime show that the system exhibits an electrical conductivity maximum as a function of colloid charge. We attribute this behavior to two main competing effects: colloid effective charge saturation due to counterion 'condensation' and diffusion slowdown due to the relaxation effect. In agreement with previous observations, we also find that the effective transported charge is larger than the one determined by the Stern layer and suggest that it corresponds to the boundary fluid layer at the surface of the colloidal particles.
Wave represents displacement Wave represents pressure Source -Sound Waves
Colorado at Boulder, University of
Wave represents displacement Wave represents pressure Source - Sound Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency Wave represents pressure Target - Radio Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency
Roberts, Jesse D.; Chang, Grace; Jones, Craig
2014-09-01T23:59:59.000Z
The numerical model, SWAN (Simulating WAves Nearshore) , was used to simulate wave conditions in Kaneohe Bay, HI in order to determine the effects of wave energy converter ( WEC ) devices on the propagation of waves into shore. A nested SWAN model was validated then used to evaluate a range of initial wave conditions: significant wave heights (H s ) , peak periods (T p ) , and mean wave directions ( MWD) . Differences between wave height s in the presence and absence of WEC device s were assessed at locations in shore of the WEC array. The maximum decrease in wave height due to the WEC s was predicted to be approximately 6% at 5 m and 10 m water depths. Th is occurred for model initiation parameters of H s = 3 m (for 5 m water depth) or 4 m (10 m water depth) , T p = 10 s, and MWD = 330deg . Subsequently, bottom orbital velocities were found to decrease by about 6%.
Maximum screening fields of superconducting multilayer structures
Gurevich, Alex
2015-01-01T23:59:59.000Z
It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields $H_s$ of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness $\\sim 0.1\\; \\mu$m at the Nb surface could increase $H_s\\simeq 240$ mT of a clean Nb up to $H_s\\simeq 290$ mT. Optimized multilayers of Nb$_3$Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.
Maximum Entropy Method Approach to $?$ Term
Masahiro Imachi; Yasuhiko Shinno; Hiroshi Yoneyama
2004-06-09T23:59:59.000Z
In Monte Carlo simulations of lattice field theory with a $\\theta$ term, one confronts the complex weight problem, or the sign problem. This is circumvented by performing the Fourier transform of the topological charge distribution $P(Q)$. This procedure, however, causes flattening phenomenon of the free energy $f(\\theta)$, which makes study of the phase structure unfeasible. In order to treat this problem, we apply the maximum entropy method (MEM) to a Gaussian form of $P(Q)$, which serves as a good example to test whether the MEM can be applied effectively to the $\\theta$ term. We study the case with flattening as well as that without flattening. In the latter case, the results of the MEM agree with those obtained from the direct application of the Fourier transform. For the former, the MEM gives a smoother $f(\\theta)$ than that of the Fourier transform. Among various default models investigated, the images which yield the least error do not show flattening, although some others cannot be excluded given the uncertainty related to statistical error.
Maximum Throughput Power Control in CDMA Wireless Networks
Mellor-Crummey, John
Maximum Throughput Power Control in CDMA Wireless Networks Anastasios Giannoulis Department introduce crosslayer, distributed power control algorithms that guarantee maximum possible data throughput performing dynamic routing and scheduling together with power control. The crosslayer interaction consists
GMM Estimation of a Maximum Entropy Distribution with Interval Data
Perloff, Jeffrey M.
GMM Estimation of a Maximum Entropy Distribution with Interval Data Ximing Wu* and Jeffrey M estimate it using a simple yet flexible maximum entropy density. Our Monte Carlo simulations show that the proposed maximum entropy density is able to approximate various distributions extremely well. The two
Coda wave interferometry 1 Coda wave interferometry
Snieder, Roel
Coda wave interferometry 1 Coda wave interferometry An interferometer is an instrument that is sensitive to the interference of two or more waves (optical or acoustic). For example, an optical interferometer uses two interfering light beams to measure small length changes. Coda wave interferometry
Scattering of internal gravity waves
Leaman Nye, Abigail
2011-04-19T23:59:59.000Z
of the perturbed buoy- ancy field throughout a period of the motion. Curves represent cross-sections taken from the incident beam (cyan); a beam after reflection from a solid horizontal bound- ary (dark blue) and a beam after interaction with the sponge formation... wavenumber components and (b) plots power spectra calculated with Fourier and maximum entropy methods. k˜ is a nondimensional wavenumber representing the number of waves in an across-beam section of length Rc. . . . . . . 114 4.7 Two-dimensional power spectra...
Free energy in plasmas under wave-induced diffusion
Fisch, N.J. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Rax, J.M. (CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France))
1993-05-01T23:59:59.000Z
When waves propagate through a bounded plasma, the wave may be amplified or damped at the expense of the plasma kinetic energy. In many cases of interest, the primary effect of the wave is to cause plasma diffusion in velocity and configuration space. In the absence of collisions, the rearrangement of the plasma conserves entropy, as large-grain structures are mixed and fine-grain structures emerge. The maximum extractable energy by waves so diffusing the plasma is a quantity of fundamental interest; it can be defined, but it is difficult to calculate. Through the consideration of specific examples, certain strategies for maximizing energy extraction are identified.
A Near Maximum Likelihood Decoding Algorithm for MIMO Systems ...
Amin Mobasher
2005-10-03T23:59:59.000Z
Oct 3, 2005 ... A Near Maximum Likelihood Decoding Algorithm for MIMO Systems Based ... models are also used for soft output decoding in MIMO systems.
Computing the Maximum Volume Inscribed Ellipsoid of a Polytopic ...
Jianzhe Zhen
2015-01-23T23:59:59.000Z
Jan 23, 2015 ... Abstract: This paper introduces a method for computing the maximum volume inscribed ellipsoid and k-ball of a projected polytope. It is known ...
Solving Maximum-Entropy Sampling Problems Using Factored Masks
Samuel Burer
2005-03-02T23:59:59.000Z
Mar 2, 2005 ... Abstract: We present a practical approach to Anstreicher and Lee's masked spectral bound for maximum-entropy sampling, and we describe ...
A masked spectral bound for maximum-entropy sampling
Kurt Anstreicher
2003-09-16T23:59:59.000Z
Sep 16, 2003 ... Abstract: We introduce a new masked spectral bound for the maximum-entropy sampling problem. This bound is a continuous generalization of ...
Maximum entropy generation in open systems: the Fourth Law?
Umberto Lucia
2010-11-17T23:59:59.000Z
This paper develops an analytical and rigorous formulation of the maximum entropy generation principle. The result is suggested as the Fourth Law of Thermodynamics.
annual maximum extent: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
of the Sixteenth Annual Conference on Neural Information Processing Systems (NIPS2002) A Maximum Entropy Approach To Computer Technologies and Information Sciences Websites...
analog fixed maximum: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
state for given entanglement which can be viewed as an analogue of the Jaynes maximum entropy principle. Pawel Horodecki; Ryszard Horodecki; Michal Horodecki 1998-05-22...
IBM Research Report Solving Maximum-Entropy Sampling ...
2005-02-28T23:59:59.000Z
Feb 28, 2005 ... Solving Maximum-Entropy Sampling Problems Using. Factored Masks. Samuel Burer. Department of Management Sciences. University of Iowa.
A Requirement for Significant Reduction in the Maximum BTU Input...
A Requirement for Significant Reduction in the Maximum BTU Input Rate of Decorative Vented Gas Fireplaces Would Impose Substantial Burdens on Manufacturers A Requirement for...
Fast waves and electron current drive in the Irvine Torus
Platt, R.C.
1987-01-01T23:59:59.000Z
This work reports the results of experimental studies of the fast wave with frequencies near the mean gyro-frequency in magnetized, toroidal plasmas with comparison to theory. Experiment investigating fast-wave dispersion and damping, and the use of unidirectional fast waves to drive steady-state electron currents were performed on the Irvine Torus. The wave was excited in the plasmas by a phased array antenna which allowed launching of uni- or bi-directional fast waves around the torus. Probe measurements of the angle of propagation of wave energy, radial wavelengths, and the direction and magnitude of radial wave phase velocities were found to be in good agreement with predictions from cold plasma theory. Measurements of fast-wave damping showed the observed damping lengths to be anomalously short when compared to predictions for electron Landau damping, transit-time magnetic pumping, and collisional damping, but may be explained by effects due to fast-wave scattering from drift-wave density fluctuations. Steady-state electron currents were driven by unidirectional fast waves. Up to 14% of the wave energy was converted to poloidal magnetic field energy. The maximum current observed was found to be in rough agreement with a prediction from quasi-linear theory.
Local Runup Amplification By Resonant Wave Interactions
Stefanakis, Themistoklis; Dutykh, Denys
2011-01-01T23:59:59.000Z
Until now the analysis of long wave runup on a plane beach has been focused on finding its maximum value, failing to capture the existence of resonant regimes. One-dimensional numerical simulations in the framework of the Nonlinear Shallow Water Equations (NSWE) are used to investigate the Boundary Value Problem (BVP) for plane and non-trivial beaches. Monochromatic waves, as well as virtual wave-gage recordings from real tsunami simulations, are used as forcing conditions to the BVP. Resonant phenomena between the incident wavelength and the beach slope are found to occur, which result in enhanced runup of non-leading waves. The evolution of energy reveals the existence of a quasi-periodic state for the case of sinusoidal waves, the energy level of which, as well as the time required to reach that state, depend on the incident wavelength for a given beach slope. Dispersion is found to slightly reduce the value of maximum runup, but not to change the overall picture. Runup amplification occurs for both leadin...
Appendix 22 Draft Nutrient Management Plan and Total Maximum Daily
Appendix 22 Draft Nutrient Management Plan and Total Maximum Daily Load for Flathead Lake, Montana. #12;11/01/01 DRAFT i October 30, 2001 Draft Nutrient Management Plan and Total Maximum Daily Load..............................................................................................................................2-11 SECTION 3.0 APPLICABLE WATER QUALITY STANDARDS
FAST SPEAKER ADAPTION VIA MAXIMUM PENALIZED LIKELIHOOD KERNEL REGRESSION
Tsang Wai Hung "Ivor"
of MLLR using non- linear regression. Specifically, kernel regression is applied with appropriate of Science and Technology Clear Water Bay, Hong Kong ABSTRACT Maximum likelihood linear regression (MLLR) has], and transformation-based methods, most notably, maximum likelihood linear regression (MLLR) adap- tation [3]. However
Digital tomosynthesis mammography using a parallel maximum likelihood reconstruction method
Meleis, Waleed
Digital tomosynthesis mammography using a parallel maximum likelihood reconstruction method Tao Wu , a Radiology Department, Massachusetts General Hospital, Boston, MA 02114 b Dept. of Electrical and Computer on an iterative maximum likelihood (ML) algorithm, is developed to provide fast reconstruction for digital
Geometrical vs wave optics under gravitational waves
Raymond Angélil; Prasenjit Saha
2015-05-20T23:59:59.000Z
We present some new derivations of the effect of a plane gravitational wave on a light ray. A simple interpretation of the results is that a gravitational wave causes a phase modulation of electromagnetic waves. We arrive at this picture from two contrasting directions, namely null geodesics and Maxwell's equations, or, geometric and wave optics. Under geometric optics, we express the geodesic equations in Hamiltonian form and solve perturbatively for the effect of gravitational waves. We find that the well-known time-delay formula for light generalizes trivially to massive particles. We also recover, by way of a Hamilton-Jacobi equation, the phase modulation obtained under wave optics. Turning then to wave optics - rather than solving Maxwell's equations directly for the fields, as in most previous approaches - we derive a perturbed wave equation (perturbed by the gravitational wave) for the electromagnetic four-potential. From this wave equation it follows that the four-potential and the electric and magnetic fields all experience the same phase modulation. Applying such a phase modulation to a superposition of plane waves corresponding to a Gaussian wave packet leads to time delays.
Philipp Gubler; Kei Suzuki; Kenji Morita; Makoto Oka
2012-12-07T23:59:59.000Z
Studies of quarkonium spectral functions at finite temperature, based on an approach combining QCD sum rules and the maximum entropy method are briefly reviewed. QCD sum rules for heavy quarkonia incorporate finite temperature effects in form of changing values of gluonic condensates that appear in the operator product expansion. These changes depend on the energy density and pressure at finite temperature, which we extract from quenched lattice QCD calculations. The maximum entropy method then allows us to obtain the most probable spectral function from the sum rules, without having to introduce any specific assumption about its functional form. Our findings suggest that the charmonium ground states of both S-wave and P-wave channels dissolve into the continuum already at temperatures around or slightly above the critical temperature T_c, while the bottomonium states are less influenced by temperature effects, surviving up to about 2.5 T_c or higher for S-wave and up to about 2.0 T_c for P-wave states.
Liu, Jian
2008-01-01T23:59:59.000Z
1992). J. Skilling, in Maximum entropy and Bayesian methods,1989). S. F. Gull, in Maximum entropy and Bayesian methods,with the classical maximum entropy (CME) technique (MEAC-
Improved constraints on transit time distributions from argon 39: A maximum entropy approach
Holzer, Mark; Primeau, Francois W
2010-01-01T23:59:59.000Z
Gull (1991), Bayesian maximum entropy image reconstruction,Atlantic venti- lated? Maximum entropy inversions of bottlefrom argon 39: A maximum entropy approach Mark Holzer 1,2
Soffer, Bernard H; Kikuchi, Ryoichi
1994-01-01T23:59:59.000Z
of Confidence for Maximum Entropy Restoration and EstimationApril 3, 1992) The Maximum Entropy method, using physicalare discussed. Maximum Entropy (ME) estimation has been
,2) provide a kinematic description of water waves, which to this point means that the conditionsWater Waves Roger Grimshaw May 7, 2003 Abstract A short review of the theory of weakly nonlinear water waves, prepared for the forthcoming Encyclopedia of Nonlinear Science 1 Introduction Water waves
Multichannel Blind Identification: From Subspace to Maximum Likelihood Methods
Tong, Lang
Multichannel Blind Identification: From Subspace to Maximum Likelihood Methods LANG TONG, MEMBER, IEEE, AND SYLVIE PERREAU Invited Paper A review of recent blind channel estimation algorithms is pre-- Blind equalization, parameter estimation, system identification. I. INTRODUCTION A. What Is Blind
Maximum containment : the most controversial labs in the world
Bruzek, Alison K. (Allison Kim)
2013-01-01T23:59:59.000Z
In 2002, following the September 11th attacks and the anthrax letters, the United States allocated money to build two maximum containment biology labs. Called Biosafety Level 4 (BSL-4) facilities, these labs were built to ...
On the maximum pressure rise rate in boosted HCCI operation
Wildman, Craig B.
This paper explores the combined effects of boosting, intake air temperature, trapped residual gas fraction, and dilution on the Maximum Pressure Rise Rate (MPRR) in a boosted single cylinder gasoline HCCI engine with ...
Maximum Photovoltaic Penetration Levels on Typical Distribution Feeders: Preprint
Hoke, A.; Butler, R.; Hambrick, J.; Kroposki, B.
2012-07-01T23:59:59.000Z
This paper presents simulation results for a taxonomy of typical distribution feeders with various levels of photovoltaic (PV) penetration. For each of the 16 feeders simulated, the maximum PV penetration that did not result in steady-state voltage or current violation is presented for several PV location scenarios: clustered near the feeder source, clustered near the midpoint of the feeder, clustered near the end of the feeder, randomly located, and evenly distributed. In addition, the maximum level of PV is presented for single, large PV systems at each location. Maximum PV penetration was determined by requiring that feeder voltages stay within ANSI Range A and that feeder currents stay within the ranges determined by overcurrent protection devices. Simulations were run in GridLAB-D using hourly time steps over a year with randomized load profiles based on utility data and typical meteorological year weather data. For 86% of the cases simulated, maximum PV penetration was at least 30% of peak load.
Bacteria Total Maximum Daily Load Task Force Final Report
Jones, C. Allan; Wagner, Kevin; Di Giovanni, George; Hauck, Larry; Mott, Joanna; Rifai, Hanadi; Srinivasan, Raghavan; Ward, George; Wythe, Kathy
2009-01-01T23:59:59.000Z
In September 2006, the Texas Commission on Environmental Quality (TCEQ) and Texas State Soil and Water Conservation Board (TSSWCB) charged a seven-person Bacteria Total Maximum Daily Load (TMDL) Task Force with: * examining approaches...
Maximum Likelihood Decoding of Reed Solomon Codes Madhu Sudan
Sudan, Madhu
Maximum Likelihood Decoding of Reed Solomon Codes Madhu Sudan Abstract We present a randomized and Welch [4] (see, for instance, Gem- mell and Sudan [9]). In this paper we present an algorithm which
Multi-Class Classification with Maximum Margin Multiple Kernel
Tomkins, Andrew
(named OBSCURE and UFO-MKL, respectively) are used to optimize primal versions of equivalent problems), the OBSCURE and UFO-MKL algorithms are compared against MCMKL #12;Multi-Class Classification with Maximum
Maximum entropy method and oscillations in the diffraction cone
O. Dumbrajs; J. Kontros; A. Lengyel
2000-07-15T23:59:59.000Z
The maximum entropy method has been applied to investigate the oscillating structure in the pbarp- and pp-elastic scattering differential cross-section at high energy and small momentum transfer. Oscillations satisfying quite realistic reliability criteria have been found.
Filtering Additive Measurement Noise with Maximum Entropy in the Mean
Henryk Gzyl; Enrique ter Horst
2007-09-04T23:59:59.000Z
The purpose of this note is to show how the method of maximum entropy in the mean (MEM) may be used to improve parametric estimation when the measurements are corrupted by large level of noise. The method is developed in the context on a concrete example: that of estimation of the parameter in an exponential distribution. We compare the performance of our method with the bayesian and maximum likelihood approaches.
The maximum entropy tecniques and the statistical description of systems
B. Z. Belashev; M. K. Suleymanov
2001-10-19T23:59:59.000Z
The maximum entropy technique (MENT) is used to determine the distribution functions of physical values. MENT naturally combines required maximum entropy, the properties of a system and connection conditions in the form of restrictions imposed on the system. It can, therefore, be employed to statistically describe closed and open systems. Examples in which MENT is used to describe equilibrium and non-equilibrium states, as well as steady states that are far from being in thermodynamic equilibrium, are discussed.
Gravitational wave radiometry: Mapping a stochastic gravitational wave background
Mitra, Sanjit [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India); Observatoire de la Cote d'Azur, BP 4229, 06304 Nice Cedex 4 (France); Dhurandhar, Sanjeev; Souradeep, Tarun [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India); Lazzarini, Albert; Mandic, Vuk; Ballmer, Stefan [LIGO Laboratory, California Institute of Technology, MS 18-34, Pasadena, California 91125 (United States); Bose, Sukanta [Department of Physics, Washington State University, Pullman, Washington 99164-2814 (United States)
2008-02-15T23:59:59.000Z
The problem of the detection and mapping of a stochastic gravitational wave background (SGWB), either cosmological or astrophysical, bears a strong semblance to the analysis of the cosmic microwave background (CMB) anisotropy and polarization, which too is a stochastic field, statistically described in terms of its correlation properties. An astrophysical gravitational wave background (AGWB) will likely arise from an incoherent superposition of unmodelled and/or unresolved sources and cosmological gravitational wave backgrounds (CGWB) are also predicted in certain scenarios. The basic statistic we use is the cross correlation between the data from a pair of detectors. In order to ''point'' the pair of detectors at different locations one must suitably delay the signal by the amount it takes for the gravitational waves (GW) to travel to both detectors corresponding to a source direction. Then the raw (observed) sky map of the SGWB is the signal convolved with a beam response function that varies with location in the sky. We first present a thorough analytic understanding of the structure of the beam response function using an analytic approach employing the stationary phase approximation. The true sky map is obtained by numerically deconvolving the beam function in the integral (convolution) equation. We adopt the maximum likelihood framework to estimate the true sky map using the conjugate gradient method that has been successfully used in the broadly similar, well-studied CMB map-making problem. We numerically implement and demonstrate the method on signal generated by simulated (unpolarized) SGWB for the GW radiometer consisting of the LIGO pair of detectors at Hanford and Livingston. We include 'realistic' additive Gaussian noise in each data stream based on the LIGO-I noise power spectral density. The extension of the method to multiple baselines and polarized GWB is outlined. In the near future the network of GW detectors, including the Advanced LIGO and Virgo detectors that will be sensitive to sources within a thousand times larger spatial volume, could provide promising data sets for GW radiometry.
the wave model A traveling wave is an organized disturbance
Winokur, Michael
1 waves the wave model A traveling wave is an organized disturbance propagating at a well-defined wave speed v. · In transverse waves the particles of the medium move perpendicular to the direction of wave propagation. · In longitudinal waves the particles of the medium move parallel to the direction
Nonlinear Landau damping of transverse electromagnetic waves in dusty plasmas
Tsintsadze, N. L. [E. Andronikashvili Institute of Physics, Tbilisi 0171 (Georgia); Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Chaudhary, Rozina [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Shah, H. A. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan)
2009-04-15T23:59:59.000Z
High-frequency transverse electromagnetic waves in a collisionless isotropic dusty plasma damp via nonlinear Landau damping. Taking into account the latter we have obtained a generalized set of Zakharov equations with local and nonlocal terms. Then from this coupled set of Zakharov equations a kinetic nonlinear Schroedinger equation with local and nonlocal nonlinearities is derived for special cases. It is shown that the modulation of the amplitude of the electromagnetic waves leads to the modulation instability through the nonlinear Landau damping term. The maximum growth rate is obtained for the special case when the group velocity of electromagnetic waves is close to the dust acoustic velocity.
Evolution of water waves generated by subaerial solid landslide S. Viroulet1,*
Paris-Sud XI, Université de
Evolution of water waves generated by subaerial solid landslide S. Viroulet1,* , D. C´ebron1,2 , O laws allow thus to predict the time evolution of the maximum amplitude wave generated by an aerial of landslide tsunamis are more dif- ficult than those generated by tectonic source due to the lack of knowledge
Iwo Bialynicki-Birula
2005-08-26T23:59:59.000Z
Photon wave function is a controversial concept. Controversies stem from the fact that photon wave functions can not have all the properties of the Schroedinger wave functions of nonrelativistic wave mechanics. Insistence on those properties that, owing to peculiarities of photon dynamics, cannot be rendered, led some physicists to the extreme opinion that the photon wave function does not exist. I reject such a fundamentalist point of view in favor of a more pragmatic approach. In my view, the photon wave function exists as long as it can be precisely defined and made useful.
Rogue Wave Modes for the Long Wave-Short Wave Resonance Kwok Wing CHOW*(1)
1 Rogue Wave Modes for the Long Wave-Short Wave Resonance Model Kwok Wing CHOW*(1) , Hiu Ning CHAN.45.Yv; 47.35.Fg ABSTRACT The long wave-short wave resonance model arises physically when the phase velocity of a long wave matches the group velocity of a short wave. It is a system of nonlinear evolution
Minimum Entangling Power is Close to Its Maximum
Jianxin Chen; Zhengfeng Ji; David W Kribs; Bei Zeng
2012-10-04T23:59:59.000Z
Given a quantum gate $U$ acting on a bipartite quantum system, its maximum (average, minimum) entangling power is the maximum (average, minimum) entanglement generation with respect to certain entanglement measure when the inputs are restricted to be product states. In this paper, we mainly focus on the 'weakest' one, i.e., the minimum entangling power, among all these entangling powers. We show that, by choosing von Neumann entropy of reduced density operator or Schmidt rank as entanglement measure, even the 'weakest' entangling power is generically very close to its maximal possible entanglement generation. In other words, maximum, average and minimum entangling powers are generically close. We then study minimum entangling power with respect to other Lipschitiz-continuous entanglement measures and generalize our results to multipartite quantum systems. As a straightforward application, a random quantum gate will almost surely be an intrinsically fault-tolerant entangling device that will always transform every low-entangled state to near-maximally entangled state.
Nonlinear fast growth of water waves under wind forcing
Brunetti, Maura; Berti, Nicolas; Kasparian, Jérôme
2014-01-01T23:59:59.000Z
In the wind-driven wave regime, the Miles mechanism gives an estimate of the growth rate of the waves under the effect of wind. We consider the case where this growth rate, normalised with respect to the frequency of the carrier wave, is of the order of the wave steepness. Using the method of multiple scales, we calculate the terms which appear in the nonlinear Schr\\"odinger (NLS) equation in this regime of fast-growing waves. We define a coordinate transformation which maps the forced NLS equation into the standard NLS with constant coefficients, that has a number of known analytical soliton solutions. Among these solutions, the Peregrine and the Akhmediev solitons show an enhancement of both their lifetime and maximum amplitude which is in qualitative agreement with the results of tank experiments and numerical simulations of dispersive focusing under the action of wind.
When are microcircuits well-modeled by maximum entropy methods?
2010-07-20T23:59:59.000Z
POSTER PRESENTATION Open Access When are microcircuits well-modeled by maximum entropy methods? Andrea K Barreiro1*, Eric T Shea-Brown1, Fred M Rieke2,3, Julijana Gjorgjieva4 From Nineteenth Annual Computational Neuroscience Meeting: CNS*2010 San... Antonio, TX, USA. 24-30 July 2010 Recent experiments in retina and cortex have demon- strated that pairwise maximum entropy (PME) methods can approximate observed spiking patterns to a high degree of accuracy [1,2]. In this paper we examine...
Valence quark distributions of the proton from maximum entropy approach
Rong Wang; Xurong Chen
2014-10-14T23:59:59.000Z
We present an attempt of maximum entropy principle to determine valence quark distributions in the proton at very low resolution scale $Q_0^2$. The initial three valence quark distributions are obtained with limited dynamical information from quark model and QCD theory. Valence quark distributions from this method are compared to the lepton deep inelastic scattering data, and the widely used CT10 and MSTW08 data sets. The obtained valence quark distributions are consistent with experimental observations and the latest global fits of PDFs. Maximum entropy method is expected to be particularly useful in the case where relatively little information from QCD calculation is given.
Valence quark distributions of the proton from maximum entropy approach
Wang, Rong
2014-01-01T23:59:59.000Z
We present an attempt of maximum entropy principle to determine valence quark distributions in the proton at very low resolution scale $Q_0^2$. The initial three valence quark distributions are obtained with limited dynamical information from quark model and QCD theory. Valence quark distributions from this method are compared to the lepton deep inelastic scattering data, and the widely used CT10 and MSTW08 data sets. The obtained valence quark distributions are consistent with experimental observations and the latest global fits of PDFs. Maximum entropy method is expected to be particularly useful in the case where relatively little information from QCD calculation is given.
Assessing complexity by means of maximum entropy models
Chliamovitch, Gregor; Velasquez, Lino
2014-01-01T23:59:59.000Z
We discuss a characterization of complexity based on successive approximations of the probability density describing a system by means of maximum entropy methods, thereby quantifying the respective role played by different orders of interaction. This characterization is applied on simple cellular automata in order to put it in perspective with the usual notion of complexity for such systems based on Wolfram classes. The overlap is shown to be good, but not perfect. This suggests that complexity in the sense of Wolfram emerges as an intermediate regime of maximum entropy-based complexity, but also gives insights regarding the role of initial conditions in complexity-related issues.
Mathur, Manikandan S.
Internal waves are a ubiquitous and significant means of momentum and energy transport in the oceans, atmosphere, and astrophysical bodies. Here, we show that internal wave propagation in nonuniform density stratifications, ...
Mercier, Matthieu J.
We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (Exp. Fluids, vol. 42, 2007, pp. 123–130). This ...
Degasperis, Antonio; Aceves, Alejandro B
2015-01-01T23:59:59.000Z
We derive the rogue wave solution of the classical massive Thirring model, that describes nonlinear optical pulse propagation in Bragg gratings. Combining electromagnetically induced transparency with Bragg scattering four-wave mixing, may lead to extreme waves at extremely low powers.
Internal wave instability: Wave-wave versus wave-induced mean flow interactions
Sutherland, Bruce
, known as parametric sub- harmonic instability, results generally when a disturbance of one frequency imparts energy to disturbances of half that frequency.13,14 Generally, a plane periodic internal wave, energy from primary waves is transferred, for example, to waves with half frequency. Self
Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino
Merlino, Robert L.
Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino Department of Physics and Astronomy with their announcement that: "We find that a new type of sound wave, namely, the dust-acoustic waves, can appear" [1 and experimental work on dust acoustic waves is given. The basic physics of the dust acoustic wave and some
Performance Assessment of the Wave Dragon Wave Energy Converter
Hansen, René Rydhof
Performance Assessment of the Wave Dragon Wave Energy Converter Based on the EquiMar Methodology S of the wave energy sector, device developers are called to provide reliable estimates on power performanceMar, Nissum Bredning, Hanstholm, North Sea, Ekofisk, Wave-to-wire, Wave energy. I. INTRODUCTION The wave
Maximum stellar mass versus cluster membership number revisited
Th. Maschberger; C. J. Clarke
2008-09-05T23:59:59.000Z
We have made a new compilation of observations of maximum stellar mass versus cluster membership number from the literature, which we analyse for consistency with the predictions of a simple random drawing hypothesis for stellar mass selection in clusters. Previously, Weidner and Kroupa have suggested that the maximum stellar mass is lower, in low mass clusters, than would be expected on the basis of random drawing, and have pointed out that this could have important implications for steepening the integrated initial mass function of the Galaxy (the IGIMF) at high masses. Our compilation demonstrates how the observed distribution in the plane of maximum stellar mass versus membership number is affected by the method of target selection; in particular, rather low n clusters with large maximum stellar masses are abundant in observational datasets that specifically seek clusters in the environs of high mass stars. Although we do not consider our compilation to be either complete or unbiased, we discuss the method by which such data should be statistically analysed. Our very provisional conclusion is that the data is not indicating any striking deviation from the expectations of random drawing.
Maximum likelihood estimation of the equity Efstathios Avdis
Kahana, Michael J.
premium is usually estimated by taking the sample mean of stock returns and subtracting a measure the expected return on the aggregate stock market less the government bill rate, is of central importance an alternative esti- mator, based on maximum likelihood, that takes into account informa- tion contained
STATE OF CALIFORNIA MAXIMUM RATED TOTAL COOLING CAPACITY
/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-27-HERS Maximum Rated Total Cooling Capacity of the installed system (Btu/hr) 3b Sum of the ARI Rated Total Cooling Capacities of multiple systems installed Cooling Capacities of the installed cooling systems must be calculated and entered in row 3b. 4a MRTCC
Maximum power tracking control scheme for wind generator systems
Mena Lopez, Hugo Eduardo
2008-10-10T23:59:59.000Z
The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...
Maximum power tracking control scheme for wind generator systems
Mena, Hugo Eduardo
2009-05-15T23:59:59.000Z
The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...
annual maximum water: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
annual maximum water First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 ORIGINAL PAPER The distribution of...
BRANCH-CUT-AND-PROPAGATE FOR THE MAXIMUM k ...
2011-03-16T23:59:59.000Z
maximum k-colorable subgraph problem consists of selecting a k-color- able induced subgraph of ..... a symmetric subgroup Sp of Aut(G) acts on Vp for all p ? [s]. Let Vp = {vp. 1,...,vp qp. } ...... [9] J. Crawford, M. Ginsberg, E. Luks, and A. Roy.
Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint
Greenberg, Albert
Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint Zhe Wang Electrical--In this paper, we develop efficient algorithm to obtain the optimal energy schedule for fading channel with energy harvesting. We assume that the side information of both the channel states and energy harvesting
What is a Hurricane? Tropical system with maximum sustained
Meyers, Steven D.
Andrew-Category 4· Category 4 Hurricane - Winds 131-155 mph. Wall failures in homes and complete roofHurricane 101 #12;What is a Hurricane? · Tropical system with maximum sustained surface wind of 74 mph or greater. A hurricane is the worst and the strongest of all tropical systems. · Also known
Individual Module Maximum Power Point Tracking for Thermoelectric Generator Systems
Schaltz, Erik
of Thermo Electric Generator (TEG) systems a power converter is often inserted between the TEG system that the TEG system produces the maximum power. However, if the conditions, e.g. temperature, health, age, etc find the best compromise of all modules. In order to increase the power production of the TEG system
Efficiency Improvement of an IPMSM using Maximum Efficiency Operating Strategy
Paderborn, Universität
Efficiency Improvement of an IPMSM using Maximum Efficiency Operating Strategy Daniel Pohlenz. These are characterized by high efficiency and high torque as well as power density. The generation of reference currents that the MTPC method deviates considerably from the best efficiency under certain boundary conditions. The use
Maximum power tracking control scheme for wind generator systems
Mena, Hugo Eduardo
2009-05-15T23:59:59.000Z
The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...
Maximum power tracking control scheme for wind generator systems
Mena Lopez, Hugo Eduardo
2008-10-10T23:59:59.000Z
The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...
MARTIN'S MAXIMUM AND TOWER FORCING SEAN COX AND MATTEO VIALE
Viale, Matteo
MARTIN'S MAXIMUM AND TOWER FORCING SEAN COX AND MATTEO VIALE Abstract. There are several examples, the Reflection Princi- ple (RP) implies that if I is a tower of ideals which concentrates on the class GIC1 of 1 [16], shows that if PFA+ or MM holds and there is an inaccessible cardinal, then there is a tower
Retrocommissioning Case Study - Applying Building Selection Criteria for Maximum Results
Luskay, L.; Haasl, T.; Irvine, L.; Frey, D.
2002-01-01T23:59:59.000Z
RETROCOMMISSIONING CASE STUDY ?Applying Building Selection Criteria for Maximum Results? Larry Luskay, Tudi Haasl, Linda Irvine Portland Energy Conservation, Inc. Portland, Oregon Donald Frey Architectural Energy Corporation Boulder.... The building was retrocommissioned by Portland Energy Conservation, Inc. (PECI), in conjunction with Architectural Energy Corporation (AEC). The building-specific goals were: 1) Obtain cost-effective energy savings from optimizing operation...
Loading on a vertical cylinder in multidirectional waves
Chaplin, J.R.; Subbiah, K. [City Univ., London (United Kingdom). Ocean Engineering Research Center; Irani, M. [National Research Council, Ottawa, Ontario (Canada). Institute for Marine Dynamics
1995-08-01T23:59:59.000Z
This paper presents laboratory measurements of local and total loading on an isolated vertical cylinder in irregular unidirectional and multidirectional waves. Maximum Keulegan-Carpenter numbers in individual waves were about 16, and maximum reynolds numbers about 3 {times} 10{sup 4}. It is shown that in these conditions, existing theoretical and numerical models underestimate the reduction in loading on a cylinder due to wave spreading. Besides the changes that are predicted when Morison`s equation is used with constant coefficients, there are hydrodynamic influences that contribute further force reductions. Comparisons with Dena`s (1977) hybrid approach suggest that in the present conditions these reductions are in the region of 3 and 6 percent for a spreading function cos{sup 2s} {theta}, with s = 8 and s = 2, respectively. Larger reductions can be expected at higher Keulegan-Carpenter numbers, though scale effects are likely to become more important in the drag-dominated regime.
Coastal Wave Generation and Wave Breaking over Terrain: Two Problems in Mesoscale Wave Dynamics
Qian, Tingting
2010-07-14T23:59:59.000Z
Two problems in mesoscale wave dynamics are addressed: (i) wave-turbulence interaction in a breaking mountain wave and (ii) gravity wave generation associated with coastal heating gradients. The mean and turbulent structures in a breaking mountain...
Coastal Wave Generation and Wave Breaking over Terrain: Two Problems in Mesoscale Wave Dynamics
Qian, Tingting
2010-07-14T23:59:59.000Z
Two problems in mesoscale wave dynamics are addressed: (i) wave-turbulence interaction in a breaking mountain wave and (ii) gravity wave generation associated with coastal heating gradients. The mean and turbulent structures in a breaking mountain...
Pacôme Delva; Marie-Christine Angonin; Philippe Tourrenc
2006-09-20T23:59:59.000Z
We calculate and compare the response of light wave interferometers and matter wave interferometers to gravitational waves. We find that metric matter wave interferometers will not challenge kilometric light wave interferometers such as Virgo or LIGO, but could be a good candidate for the detection of very low frequency gravitational waves.
Maximum Entropy Principle and the Higgs Boson Mass
Alves, Alexandre; da Silva, Roberto
2014-01-01T23:59:59.000Z
A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.
Maximum Entropy Principle and the Higgs Boson Mass
Alexandre Alves; Alex G. Dias; Roberto da Silva
2014-11-18T23:59:59.000Z
A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.
Cycloidal Wave Energy Converter
Stefan G. Siegel, Ph.D.
2012-11-30T23:59:59.000Z
This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will exceed this initial performance estimates. In advancing the Technology Readiness Level (TRL) of this type of wave energy converter from 3 to 4, we find the CycWEC to exceed our initial estimates in terms of hydrodynamic performance. Once fully developed and optimized, it has the potential to not just outperform all other WEC technologies, but to also deliver power at a lower LCOE than competing conventional renewables like wind and solar. Given the large wave power resource both domestically and internationally, this technology has the potential to lead to a large improvement in our ability to produce clean electricity at affordable cost.
Max '91: flare research at the next solar maximum
Dennis, B.; Canfield, R.; Bruner, M.; Emslie, G.; Hildner, E.; Hudson, H.; Hurford, G.; Lin, R.; Novick, R.; Tarbell, T.
1988-01-01T23:59:59.000Z
To address the central scientific questions surrounding solar flares, coordinated observations of electromagnetic radiation and energetic particles must be made from spacecraft, balloons, rockets, and ground-based observatories. A program to enhance capabilities in these areas in preparation for the next solar maximum in 1991 is recommended. The major scientific issues are described, and required observations and coordination of observations and analyses are detailed. A program plan and conceptual budgets are provided.
Maximum Entry and Mandatory Separation Ages for Certain Security Employees
Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]
2001-10-11T23:59:59.000Z
The policy establishes the DOE policy on maximum entry and mandatory separation ages for primary or secondary positions covered under special statutory retirement provisions and for those employees whose primary duties are the protection of officials of the United States against threats to personal safety or the investigation, apprehension, and detention of individuals suspected or convicted of offenses against the criminal laws of the United States. Admin Chg 1, dated 12-1-11, cancels DOE P 310.1.
Maximum entropy method for reconstruction of the CMB images
A. T. Bajkova
2002-05-21T23:59:59.000Z
We propose a new approach for the accurate reconstruction of cosmic microwave background distributions from observations containing in addition to the primary fluctuations the radiation from unresolved extragalactic point sources and pixel noise. The approach uses some effective realizations of the well-known maximum entropy method and principally takes into account {\\it a priori} information about finiteness and spherical symmetry of the power spectrum of the CMB satisfying the Gaussian statistics.
Maximum total organic carbon limit for DWPF melter feed
Choi, A.S.
1995-03-13T23:59:59.000Z
DWPF recently decided to control the potential flammability of melter off-gas by limiting the total carbon content in the melter feed and maintaining adequate conditions for combustion in the melter plenum. With this new strategy, all the LFL analyzers and associated interlocks and alarms were removed from both the primary and backup melter off-gas systems. Subsequently, D. Iverson of DWPF- T{ampersand}E requested that SRTC determine the maximum allowable total organic carbon (TOC) content in the melter feed which can be implemented as part of the Process Requirements for melter feed preparation (PR-S04). The maximum TOC limit thus determined in this study was about 24,000 ppm on an aqueous slurry basis. At the TOC levels below this, the peak concentration of combustible components in the quenched off-gas will not exceed 60 percent of the LFL during off-gas surges of magnitudes up to three times nominal, provided that the melter plenum temperature and the air purge rate to the BUFC are monitored and controlled above 650 degrees C and 220 lb/hr, respectively. Appropriate interlocks should discontinue the feeding when one or both of these conditions are not met. Both the magnitude and duration of an off-gas surge have a major impact on the maximum TOC limit, since they directly affect the melter plenum temperature and combustion. Although the data obtained during recent DWPF melter startup tests showed that the peak magnitude of a surge can be greater than three times nominal, the observed duration was considerably shorter, on the order of several seconds. The long surge duration assumed in this study has a greater impact on the plenum temperature than the peak magnitude, thus making the maximum TOC estimate conservative. Two models were used to make the necessary calculations to determine the TOC limit.
Occam's Razor Cuts Away the Maximum Entropy Principle
Rudnicki, ?ukasz
2014-01-01T23:59:59.000Z
I show that the maximum entropy principle can be replaced by a more natural assumption, that there exists a phenomenological function of entropy consistent with the microscopic model. The requirement of existence provides then a unique construction of the related probability density. I conclude the letter with an axiomatic formulation of the notion of entropy, which is suitable for exploration of the non-equilibrium phenomena.
PNNL: A Supervised Maximum Entropy Approach to Word Sense Disambiguation
Tratz, Stephen C.; Sanfilippo, Antonio P.; Gregory, Michelle L.; Chappell, Alan R.; Posse, Christian; Whitney, Paul D.
2007-06-23T23:59:59.000Z
In this paper, we described the PNNL Word Sense Disambiguation system as applied to the English All-Word task in Se-mEval 2007. We use a supervised learning approach, employing a large number of features and using Information Gain for dimension reduction. Our Maximum Entropy approach combined with a rich set of features produced results that are significantly better than baseline and are the highest F-score for the fined-grained English All-Words subtask.
Some interesting consequences of the maximum entropy production principle
Martyushev, L. M. [Russian Academy of Sciences, Institute of Industrial Ecology, Ural Division (Russian Federation)], E-mail: mlm@ecko.uran.ru
2007-04-15T23:59:59.000Z
Two nonequilibrium phase transitions (morphological and hydrodynamic) are analyzed by applying the maximum entropy production principle. Quantitative analysis is for the first time compared with experiment. Nonequilibrium crystallization of ice and laminar-turbulent flow transition in a circular pipe are examined as examples of morphological and hydrodynamic transitions, respectively. For the latter transition, a minimum critical Reynolds number of 1200 is predicted. A discussion of this important and interesting result is presented.
Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensembles out-of-equilibrium
Crooks, Gavin E.
2006-01-01T23:59:59.000Z
1957). J. Skilling, in Maximum Entropy and Bayesian Methods,45–52. J. Skilling, in Maximum Entropy and Bayesian Methods,e C. C. Rodriguez, in Maximum Entropy and Bayesian Methods,
Deriving the continuity of maximum-entropy basis functions via variational analysis
Sukumar, N.; Wets, R. J. -B.
2007-01-01T23:59:59.000Z
and V. J. DellaPietra, A maximum entropy approach to naturalJ. and R. K. Bryan, Maximum entropy image reconstruction:Heidelberg, Continuity of maximum-entropy basis functions p
Characteristics of transverse waves in chromospheric mottles
Kuridze, D.; Mathioudakis, M.; Jess, D. B.; Keenan, F. P. [Astrophysics Research Center, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN (United Kingdom); Verth, G.; Erdélyi, R. [Solar Physics and Space Plasma Research Center (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Morton, R. J. [Mathematics and Information Science, Northumbria University, Camden Street, Newcastle Upon Tyne NE1 8ST (United Kingdom); Christian, D. J., E-mail: dkuridze01@qub.ac.uk [Department of Physics and Astronomy, California State University, Northridge, CA 91330 (United States)
2013-12-10T23:59:59.000Z
Using data obtained by the high temporal and spatial resolution Rapid Oscillations in the Solar Atmosphere instrument on the Dunn Solar Telescope, we investigate at an unprecedented level of detail transverse oscillations in chromospheric fine structures near the solar disk center. The oscillations are interpreted in terms of propagating and standing magnetohydrodynamic kink waves. Wave characteristics including the maximum transverse velocity amplitude and the phase speed are measured as a function of distance along the structure's length. Solar magnetoseismology is applied to these measured parameters to obtain diagnostic information on key plasma parameters (e.g., magnetic field, density, temperature, flow speed) of these localized waveguides. The magnetic field strength of the mottle along the ?2 Mm length is found to decrease by a factor of 12, while the local plasma density scale height is ?280 ± 80 km.
Nonlinear spherical Alfven waves
Ulf Torkelsson; G. Christopher Boynton
1997-09-23T23:59:59.000Z
We present an one-dimensional numerical study of Alfven waves propagating along a radial magnetic field. Neglecting losses, any spherical Alfven wave, no matter how small its initial amplitude is, becomes nonlinear at sufficiently large radii. From previous simulations of Alfven waves in plane parallel atmospheres we did expect the waves to steepen and produce current sheets in the nonlinear regime, which was confirmed by our new calculations. On the other hand we did find that even the least nonlinear waves were damped out almost completely before 10 solar radii. A damping of that kind is required by models of Alfven wave-driven winds from old low-mass stars as these winds are mainly accelerated within a few stellar radii.
Structure-borne sound Flexural wave (bending wave)
Berlin,Technische Universität
1 Structure-borne sound · Flexural wave (bending wave) »One dimensional (beam) +(/x)dx +(/x)dx = (/x) (/x)dx=(2/x2)dx Mz +(Mz/x)dx Mz vy Fy Fy +(Fy/x)dx Structure-borne sound · Bending wave flexural wave #12;2 Structure-borne sound · Two obliquely propagating waves + - + + - + - Structure
Wave Propagation Theory 2.1 The Wave Equation
2 Wave Propagation Theory 2.1 The Wave Equation The wave equation in an ideal fluid can be derived #12;66 2. Wave Propagation Theory quantities of the quiescent (time independent) medium are identified perturbations is much smaller than the speed of sound. 2.1.1 The Nonlinear Wave Equation Retaining higher
Mercier, Matthieu J; Mathur, Manikandan; Gostiaux, Louis; Peacock, Thomas; Dauxois, Thierry
2015-01-01T23:59:59.000Z
We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (2007). This mechanism, which involves a tunable source comprised of oscillating plates, has so far been used for a few fundamental studies of internal waves, but its full potential has yet to be realized. Our studies reveal that this approach is capable of producing a wide variety of two-dimensional wave fields, including plane waves, wave beams and discrete vertical modes in finite-depth stratifications. The effects of discretization by a finite number of plates, forcing amplitude and angle of propagation are investigated, and it is found that the method is remarkably efficient at generating a complete wave field despite forcing only one velocity component in a controllable manner. We furthermore find that the nature of the radiated wave field is well predicted using Fourier transforms of the spatial structure of the wave generator.
Directed Relativistic Blast Wave
Andrei Gruzinov
2007-04-23T23:59:59.000Z
A spherically symmetrical ultra-relativistic blast wave is not an attractor of a generic asymmetric explosion. Spherical symmetry is reached only by the time the blast wave slows down to non-relativistic velocities, when the Sedov-Taylor-von Neumann attractor solution sets in. We show however, that a directed relativistic explosion, with the explosion momentum close to the explosion energy, produces a blast wave with a universal intermediate asymptotic -- a selfsimilar directed ultra-relativistic blast wave. This universality might be of interest for the astrophysics of gamma-ray burst afterglows.
Characterising the acceleration phase of blast wave formation
Fox, T. E., E-mail: tef503@york.ac.uk; Pasley, J. [York Plasma Institute, University of York, York YO10 5DD (United Kingdom); Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX (United Kingdom); Robinson, A. P. L.; Schmitz, H. [Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX (United Kingdom)
2014-10-15T23:59:59.000Z
Intensely heated, localised regions in uniform fluids will rapidly expand and generate an outwardly propagating blast wave. The Sedov-Taylor self-similar solution for such blast waves has long been studied and applied to a variety of scenarios. A characteristic time for their formation has also long been identified using dimensional analysis, which by its very nature, can offer several interpretations. We propose that, rather than simply being a characteristic time, it may be interpreted as the definitive time taken for a blast wave resulting from an intense explosion in a uniform media to contain its maximum kinetic energy. A scaling relation for this measure of the acceleration phase, preceding the establishment of the blast wave, is presented and confirmed using a 1D planar hydrodynamic model.
Energy of Alfven waves generated during magnetic reconnection
Wang, L C; Ma, Z W; Zhang, X; Lee, L C
2015-01-01T23:59:59.000Z
A new method for the determination of the Alfven wave energy generated during magnetic reconnection is introduced and used to analyze the results from two-dimensional MHD simulations. It is found that the regions with strong Alfven wave perturbations almost coincide with that where both magnetic-field lines and flow-stream lines are bent, suggesting that this method is reliable for identifying Alfven waves. The magnetic energy during magnetic reconnection is mainly transformed into the thermal energy. The conversion rate to Alfven wave energy from the magnetic energy is strongly correlated to the magnetic reconnection rate. The maximum conversion rate at the time with the peak reconnection rate is found to be only about 4% for the cases with the plasma beta=0.01,0.1, and 1.0.
Wave Energy challenges and possibilities
© Wave Energy challenges and possibilities By: Per Resen Steenstrup www.WaveStarEnergy.com Risø-R-1608(EN) 161 #12;© Wave energy is an old story.... The first wave energy patent is 200 years old. Over the last 100 years more than 200 new wave energy devices have been developped and more than 1.000 patents
Better Nonlinear Models from Noisy Data: Attractors with Maximum Likelihood
Patrick E. McSharry; Leonard A. Smith
1999-11-30T23:59:59.000Z
A new approach to nonlinear modelling is presented which, by incorporating the global behaviour of the model, lifts shortcomings of both least squares and total least squares parameter estimates. Although ubiquitous in practice, a least squares approach is fundamentally flawed in that it assumes independent, normally distributed (IND) forecast errors: nonlinear models will not yield IND errors even if the noise is IND. A new cost function is obtained via the maximum likelihood principle; superior results are illustrated both for small data sets and infinitely long data streams.
Application of Maximum Entropy Method to Dynamical Fermions
Jonathan Clowser; Costas Strouthos
2001-10-16T23:59:59.000Z
The Maximum Entropy Method is applied to dynamical fermion simulations of the (2+1)-dimensional Nambu-Jona-Lasinio model. This model is particularly interesting because at T=0 it has a broken phase with a rich spectrum of mesonic bound states and a symmetric phase where there are resonances, and hence the simple pole assumption of traditional fitting procedures breaks down. We present results extracted from simulations on large lattices for the spectral functions of the elementary fermion, the pion, the sigma, the massive pseudoscalar meson and the symmetric phase resonances.
Improving predictability of time series using maximum entropy methods
Gregor Chliamovitch; Alexandre Dupuis; Bastien Chopard; Anton Golub
2014-11-28T23:59:59.000Z
We discuss how maximum entropy methods may be applied to the reconstruction of Markov processes underlying empirical time series and compare this approach to usual frequency sampling. It is shown that, at least in low dimension, there exists a subset of the space of stochastic matrices for which the MaxEnt method is more efficient than sampling, in the sense that shorter historical samples have to be considered to reach the same accuracy. Considering short samples is of particular interest when modelling smoothly non-stationary processes, for then it provides, under some conditions, a powerful forecasting tool. The method is illustrated for a discretized empirical series of exchange rates.
Reducing Degeneracy in Maximum Entropy Models of Networks
Horvát, Szabolcs; Toroczkai, Zoltán
2014-01-01T23:59:59.000Z
Based on Jaynes's maximum entropy principle, exponential random graphs provide a family of principled models that allow the prediction of network properties as constrained by empirical data. However, their use is often hindered by the degeneracy problem characterized by spontaneous symmetry-breaking, where predictions simply fail. Here we show that degeneracy appears when the corresponding density of states function is not log-concave. We propose a solution to the degeneracy problem for a large class of models by exploiting the nonlinear relationships between the constrained measures to convexify the domain of the density of states. We demonstrate the effectiveness of the method on examples, including on Zachary's karate club network data.
Improving predictability of time series using maximum entropy methods
Chliamovitch, Gregor; Chopard, Bastien; Golub, Anton
2014-01-01T23:59:59.000Z
We discuss how maximum entropy methods may be applied to the reconstruction of Markov processes underlying empirical time series and compare this approach to usual frequency sampling. It is shown that, at least in low dimension, there exists a subset of the space of stochastic matrices for which the MaxEnt method is more efficient than sampling, in the sense that shorter historical samples have to be considered to reach the same accuracy. Considering short samples is of particular interest when modelling smoothly non-stationary processes, for then it provides, under some conditions, a powerful forecasting tool. The method is illustrated for a discretized empirical series of exchange rates.
Excited nucleon spectrum from lattice QCD with maximum entropy method
K. Sasaki; S. Sasaki; T. Hatsuda; M. Asakawa
2003-09-29T23:59:59.000Z
We study excited states of the nucleon in quenched lattice QCD with the spectral analysis using the maximum entropy method. Our simulations are performed on three lattice sizes $16^3\\times 32$, $24^3\\times 32$ and $32^3\\times 32$, at $\\beta=6.0$ to address the finite volume issue. We find a significant finite volume effect on the mass of the Roper resonance for light quark masses. After removing this systematic error, its mass becomes considerably reduced toward the direction to solve the level order puzzle between the Roper resonance $N'(1440)$ and the negative-parity nucleon $N^*(1535)$.
Wave-Corpuscle Mechanics for Electric Charges
Babin, Anatoli; Figotin, Alexander
2010-01-01T23:59:59.000Z
superposition in nonlinear wave dynamics. Rev. Math. Phys.6. Babin, A. , Figotin, A. : Wave-corpuscle mechanics forV. , Fortunato, D. : Solitary waves in the nonlinear wave
Wave Energy Resource Analysis for Use in Wave Energy Conversion
Pastor, J.; Liu, Y.; Dou, Y.
2014-01-01T23:59:59.000Z
In order to predict the response of wave energy converters an accurate representation of the wave climate resource is crucial. This paper gives an overview of wave resource modeling techniques as well as detailing a methodology for estimating...
Modulational instability of Rossby and drift waves and generation of zonal jets
Colm Connaughton; Balu Nadiga; Sergey Nazarenko; Brenda Quinn
2009-05-14T23:59:59.000Z
We study the modulational instability of geophysical Rossby and plasma drift waves within the Charney-Hasegawa-Mima (CHM) model both theoretically, using truncated (four-mode and three-mode) models, and numerically, using direct simulations of CHM equation in the Fourier space. The linear theory predicts instability for any amplitude of the primary wave. For strong primary waves the most unstable modes are perpendicular to the primary wave, which correspond to generation of a zonal flow if the primary wave is purely meridional. For weaker waves, the maximum growth occurs for off-zonal inclined modulations. For very weak primary waves the unstable waves are close to being in three-wave resonance with the primary wave. The nonlinear theory predicts that the zonal flows generated by the linear instability experience pinching into narrow zonal jets. Our numerical simulations confirm the theoretical predictions of the linear theory as well as of the nonlinear pinching. We find that, for strong primary waves, these narrow zonal jets further roll up into Karman-like vortex streets. On the other hand, for weak primary waves, the growth of the unstable mode reverses and the system oscillates between a dominant jet and a dominate primary wave. The 2D vortex streets appear to be more stable than purely 1D zonal jets, and their zonal-averaged speed can reach amplitudes much stronger than is allowed by the Rayleigh-Kuo instability criterion for the 1D case. We find that the truncation models work well for both the linear stage and and often even for the medium-term nonlinear behavior. In the long term, the system transitions to turbulence helped by the vortex-pairing instability (for strong waves) and by the resonant wave-wave interactions (for weak waves).
Harmonic generation of gravitational wave induced Alfven waves
Mats Forsberg; Gert Brodin
2007-11-26T23:59:59.000Z
Here we consider the nonlinear evolution of Alfven waves that have been excited by gravitational waves from merging binary pulsars. We derive a wave equation for strongly nonlinear and dispersive Alfven waves. Due to the weak dispersion of the Alfven waves, significant wave steepening can occur, which in turn implies strong harmonic generation. We find that the harmonic generation is saturated due to dispersive effects, and use this to estimate the resulting spectrum. Finally we discuss the possibility of observing the above process.
J X Zheng-Johansson; P-I Johansson
2006-08-27T23:59:59.000Z
The electromagnetic component waves, comprising together with their generating oscillatory massless charge a material particle, will be Doppler shifted when the charge hence particle is in motion, with a velocity $v$, as a mere mechanical consequence of the source motion. We illustrate here that two such component waves generated in opposite directions and propagating at speed $c$ between walls in a one-dimensional box, superpose into a traveling beat wave of wavelength ${\\mit\\Lambda}_d$$=(\\frac{v}{c}){\\mit\\Lambda}$ and phase velocity $c^2/v+v$ which resembles directly L. de Broglie's hypothetic phase wave. This phase wave in terms of transporting the particle mass at the speed $v$ and angular frequency ${\\mit\\Omega}_d=2\\pi v /{\\mit\\Lambda}_d$, with ${\\mit\\Lambda}_d$ and ${\\mit\\Omega}_d$ obeying the de Broglie relations, represents a de Broglie wave. The standing-wave function of the de Broglie (phase) wave and its variables for particle dynamics in small geometries are equivalent to the eigen-state solutions to Schr\\"odinger equation of an identical system.
Secondary dust density waves excited by nonlinear dust acoustic waves
Heinrich, J. R.; Kim, S.-H.; Meyer, J. K.; Merlino, R. L. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States); Rosenberg, M. [Department of Electrical and Computer Engineering, University of California, San Diego, California 92093 (United States)
2012-08-15T23:59:59.000Z
Secondary dust density waves were observed in conjunction with high amplitude (n{sub d}/n{sub d0}>2) dust acoustic waves (DAW) that were spontaneously excited in a dc glow discharge dusty plasma in the moderately coupled, {Gamma}{approx}1, state. The high amplitude dust acoustic waves produced large dust particle oscillations, displacements, and trapping. Secondary dust density waves were excited in the wave troughs of the high amplitude DAWs. The waveforms, amplitudes, wavelengths, and wave speeds of the primary DAWs and the secondary waves were measured. A dust-dust streaming instability is discussed as a possible mechanism for the production of the secondary waves.
Evolution of a wave packet scattered by a one-dimensional potential
Khachatrian, A Zh; Alexanyan, Al G; Khoetsyan, V A; Alexanyan, N A
2013-06-30T23:59:59.000Z
We consider the evolution of a wave packet that is made up of a group of the wave functions describing the stationary scattering process and tunnels through a one-dimensional potential of arbitrary form. As the main characteristics of the time difference of the tunnelling process, use is made of the propagation speed of the wave-packet maximum. We show that the known Hartman formula for the tunnelling time corresponds to the wave packet with a wavenumber-uniform spectral composition in the case, when the phase and transmission coefficient modulus dispersions are taken into account only in the linear approximation. The amplitude of the main peak of the transmitted wave intensity is proven to be independent of the tunnelling time and is determined by the transmission coefficient of the spectral component at the carrier frequency and the spectral width of the wave packet. In the limit of an infinitely wide potential barrier the amplitude of the wave-packet maximum is shown to tend to zero slower than the tunnelling time tends to its asymptotic value, i.e., indeed we deal with the paradox of an infinitely large propagation speed of a wave disturbance through the barrier. (propagation of wave fronts)
Recirculation in multiple wave conversions
Brizard, A.J.
2008-01-01T23:59:59.000Z
model lies with the simple wave energy conservation law itthe recirculation of wave energy introduces interference e?particles, the tertiary-wave energy may be negative and thus
Arnold Schwarzenegger CALIFORNIA OCEAN WAVE
Arnold Schwarzenegger Governor CALIFORNIA OCEAN WAVE ENERGY ASSESSMENT Prepared For: California this report as follows: Previsic, Mirko. 2006. California Ocean Wave Energy Assessment. California Energy Systems Integration Â· Transportation California Ocean Wave Energy Assessment is the final report
Roberts, Jesse D.; Chang, Grace; Magalen, Jason; Jones, Craig
2014-09-01T23:59:59.000Z
A modified version of an indust ry standard wave modeling tool, SNL - SWAN, was used to perform model simulations for hourly initial wave conditio ns measured during the month of October 2009. The model was run with an array of 50 wave energy converters (WECs) and compared with model runs without WECs. Maximum changes in H s were found in the lee of the WEC array along the angles of incident wave dire ction and minimal changes were found along the western side of the model domain due to wave shadowing by land. The largest wave height reductions occurred during observed typhoon conditions and resulted in 14% decreases in H s along the Santa Cruz shoreline . Shoreline reductions in H s were 5% during s outh swell wave conditions and negligible during average monthly wave conditions.
B. V. Ivanov
1997-05-21T23:59:59.000Z
A coordinate transformation is found which diagonalizes the axisymmetric pp-waves. Its effect upon concrete solutions, including impulsive and shock waves, is discussed.
Wave-wave interactions in solar type III radio bursts
Thejappa, G. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); MacDowall, R. J. [NASA/Goddard Space Flight Center, Greenbelt MD 20771 (United States)
2014-02-11T23:59:59.000Z
The high time resolution observations from the STEREO/WAVES experiment show that in type III radio bursts, the Langmuir waves often occur as localized magnetic field aligned coherent wave packets with durations of a few ms and with peak intensities well exceeding the strong turbulence thresholds. Some of these wave packets show spectral signatures of beam-resonant Langmuir waves, down- and up-shifted sidebands, and ion sound waves, with frequencies, wave numbers, and tricoherences satisfying the resonance conditions of the oscillating two stream instability (four wave interaction). The spectra of a few of these wave packets also contain peaks at f{sub pe}, 2f{sub pe} and 3 f{sub pe} (f{sub pe} is the electron plasma frequency), with frequencies, wave numbers and bicoherences (computed using the wavelet based bispectral analysis techniques) satisfying the resonance conditions of three wave interactions: (1) excitation of second harmonic electromagnetic waves as a result of coalescence of two oppositely propagating Langmuir waves, and (2) excitation of third harmonic electromagnetic waves as a result of coalescence of Langmuir waves with second harmonic electromagnetic waves. The implication of these findings is that the strong turbulence processes play major roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation in type III radio bursts.
Probable maximum flood control; Yucca Mountain Site Characterization Project
DeGabriele, C.E.; Wu, C.L. [Bechtel National, Inc., San Francisco, CA (United States)
1991-11-01T23:59:59.000Z
This study proposes preliminary design concepts to protect the waste-handling facilities and all shaft and ramp entries to the underground from the probable maximum flood (PMF) in the current design configuration for the proposed Nevada Nuclear Waste Storage Investigation (NNWSI) repository protection provisions were furnished by the United States Bureau of Reclamation (USSR) or developed from USSR data. Proposed flood protection provisions include site grading, drainage channels, and diversion dikes. Figures are provided to show these proposed flood protection provisions at each area investigated. These areas are the central surface facilities (including the waste-handling building and waste treatment building), tuff ramp portal, waste ramp portal, men-and-materials shaft, emplacement exhaust shaft, and exploratory shafts facility.
Maximum Margin Clustering for State Decomposition of Metastable Systems
Wu, Hao
2015-01-01T23:59:59.000Z
When studying a metastable dynamical system, a prime concern is how to decompose the phase space into a set of metastable states. Unfortunately, the metastable state decomposition based on simulation or experimental data is still a challenge. The most popular and simplest approach is geometric clustering which is developed based on the classical clustering technique. However, the prerequisites of this approach are: (1) data are obtained from simulations or experiments which are in global equilibrium and (2) the coordinate system is appropriately selected. Recently, the kinetic clustering approach based on phase space discretization and transition probability estimation has drawn much attention due to its applicability to more general cases, but the choice of discretization policy is a difficult task. In this paper, a new decomposition method designated as maximum margin metastable clustering is proposed, which converts the problem of metastable state decomposition to a semi-supervised learning problem so that...
Efficiency at maximum power of a chemical engine
Hooyberghs, Hans; Salazar, Alberto; Indekeu, Joseph O; Broeck, Christian Van den
2013-01-01T23:59:59.000Z
A cyclically operating chemical engine is considered that converts chemical energy into mechanical work. The working fluid is a gas of finite-sized spherical particles interacting through elastic hard collisions. For a generic transport law for particle uptake and release, the efficiency at maximum power $\\eta$ takes the form 1/2+c\\Delta \\mu + O(\\Delta \\mu^2), with 1/2 a universal constant and $\\Delta \\mu$ the chemical potential difference between the particle reservoirs. The linear coefficient c is zero for engines featuring a so-called left/right symmetry or particle fluxes that are antisymmetric in the applied chemical potential difference. Remarkably, the leading constant in $\\eta$ is non-universal with respect to an exceptional modification of the transport law. For a nonlinear transport model we obtain \\eta = 1/(\\theta +1), with \\theta >0 the power of $\\Delta \\mu$ in the transport equation
Reduction in maximum time uncertainty of paired time signals
Theodosiou, George E. (West Chicago, IL); Dawson, John W. (Clarendon Hills, IL)
1983-01-01T23:59:59.000Z
Reduction in the maximum time uncertainty (t.sub.max -t.sub.min) of a series of paired time signals t.sub.1 and t.sub.2 varying between two input terminals and representative of a series of single events where t.sub.1 .ltoreq.t.sub.2 and t.sub.1 +t.sub.2 equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t.sub.min) of the first signal t.sub.1 closer to t.sub.max and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20-800.
Reduction in maximum time uncertainty of paired time signals
Theodosiou, G.E.; Dawson, J.W.
1983-10-04T23:59:59.000Z
Reduction in the maximum time uncertainty (t[sub max]--t[sub min]) of a series of paired time signals t[sub 1] and t[sub 2] varying between two input terminals and representative of a series of single events where t[sub 1][<=]t[sub 2] and t[sub 1]+t[sub 2] equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t[sub min]) of the first signal t[sub 1] closer to t[sub max] and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20--800. 6 figs.
Reduction in maximum time uncertainty of paired time signals
Theodosiou, G.E.; Dawson, J.W.
1981-02-11T23:59:59.000Z
Reduction in the maximum time uncertainty (t/sub max/ - t/sub min/) of a series of paired time signals t/sub 1/ and t/sub 2/ varying between two input terminals and representative of a series of single events where t/sub 1/ less than or equal to t/sub 2/ and t/sub 1/ + t/sub 2/ equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t/sub min/) of the first signal t/sub 1/ closer to t/sub max/ and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20 to 800.
Improved Maximum Entropy Analysis with an Extended Search Space
Alexander Rothkopf
2013-01-07T23:59:59.000Z
The standard implementation of the Maximum Entropy Method (MEM) follows Bryan and deploys a Singular Value Decomposition (SVD) to limit the dimensionality of the underlying solution space apriori. Here we present arguments based on the shape of the SVD basis functions and numerical evidence from a mock data analysis, which show that the correct Bayesian solution is not in general recovered with this approach. As a remedy we propose to extend the search basis systematically, which will eventually recover the full solution space and the correct solution. In order to adequately approach problems where an exponentially damped kernel is used, we provide an open-source implementation, using the C/C++ language that utilizes high precision arithmetic adjustable at run-time. The LBFGS algorithm is included in the code in order to attack problems without the need to resort to a particular search space restriction.
Quantum maximum entropy principle for a system of identical particles
Trovato, M. [Dipartimento di Matematica, Universita di Catania, Viale A. Doria, 95125 Catania (Italy); Reggiani, L. [Dipartimento di Ingegneria dell' Innovazione and CNISM, Universita del Salento, Via Arnesano s/n, 73100 Lecce (Italy)
2010-02-15T23:59:59.000Z
By introducing a functional of the reduced density matrix, we generalize the definition of a quantum entropy which incorporates the indistinguishability principle of a system of identical particles. With the present definition, the principle of quantum maximum entropy permits us to solve the closure problem for a quantum hydrodynamic set of balance equations corresponding to an arbitrary number of moments in the framework of extended thermodynamics. The determination of the reduced Wigner function for equilibrium and nonequilibrium conditions is found to become possible only by assuming that the Lagrange multipliers can be expanded in powers of (Planck constant/2pi){sup 2}. Quantum contributions are expressed in powers of (Planck constant/2pi){sup 2} while classical results are recovered in the limit (Planck constant/2pi)->0.
Full wave simulations of lower hybrid wave propagation in tokamaks
Wright, John C.
Full wave simulations of lower hybrid wave propagation in tokamaks J. C. Wright , P. T. Bonoli , C hybrid (LH) waves have the attractive property of damping strongly via electron Landau resonance. Consequently these waves are well-suited to driving current in the plasma periphery where the electron
Modulational instability of Rossby and drift waves and generation of zonal jets
Connaughton, Colm; Nazarenko, Sergey; Quinn, Brenda
2009-01-01T23:59:59.000Z
We study the modulational instability of geophysical Rossby and plasma drift waves within the Charney-Hasegawa-Mima (CHM) model both theoretically, using truncated (four-mode and three-mode) models, and numerically, using direct simulations of CHM equation in the Fourier space. The linear theory predicts instability for any amplitude of the primary wave. For strong primary waves the most unstable modes are perpendicular to the primary wave, which correspond to generation of a zonal flow if the primary wave is purely meridional. For weaker waves, the maximum growth occurs for off-zonal inclined modulations. For very weak primary waves the unstable waves are close to being in three-wave resonance with the primary wave. The nonlinear theory predicts that the zonal flows generated by the linear instability experience pinching into narrow zonal jets. Our numerical simulations confirm the theoretical predictions of the linear theory as well as of the nonlinear pinching. We find that, for strong primary waves, these...
Broader source: Energy.gov (indexed) [DOE]
Water Power Peer Review WindWaveFloat Alla Weinstein Principle Power, Inc. aweinstein@principlepowerinc.com November 1, 2011 2 | Wind and Water Power Program eere.energy.gov...
Cavaleri, Luigi; Bidlot, Jean-Raymond
2015-01-01T23:59:59.000Z
We consider the effect of rain on wind wave generation and dissipation. Rain falling on a wavy surface may have a marked tendency to dampen the shorter waves in the tail of the spectrum, the related range increasing with the rain rate. Following the coupling between meteorological and wave models, we derive that on the whole this should imply stronger wind and higher waves in the most energetic part of the spectrum. This is supported by numerical experiments. However, a verification based on the comparison between operational model results and measured data suggests that the opposite is true. This leads to a keen analysis of the overall process, in particular on the role of the tail of the spectrum in modulating the wind input and the white-capping. We suggest that the relationship between white-capping and generation by wind is deeper and more implicative than presently generally assumed.
Hietala, V.M.; Vawter, G.A.
1993-12-14T23:59:59.000Z
The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size. 4 figures.
Halliday, David Fraser
2009-01-01T23:59:59.000Z
This thesis concerns the application of seismic interferometry to surface waves. Seismic interferometry is the process by which the wavefield between two recording locations is estimated, resulting in new recordings at ...
Kim, Seoktae
2006-04-12T23:59:59.000Z
New millimeter wave interferometric, multifunctional sensors have been studied for industrial sensing applications: displacement measurement, liquid-level gauging and velocimetry. Two types of configuration were investigated to implement the sensor...
Bush, John W. M.
Yves Couder, Emmanuel Fort, and coworkers recently discovered that a millimetric droplet sustained on the surface of a vibrating fluid bath may self-propel through a resonant interaction with its own wave field. This article ...
Autoresonant Excitation of Diocotron Waves
Wurtele, Jonathan
of the wave, the pump and the wave will phase lock at very low wave amplitude. When the pump reachesAutoresonant Excitation of Diocotron Waves J. Fajans E. Gilson U.C. Berkeley L. Friedland Hebrew of phase with the oscillator, and the os- cillator's amplitude will decrease, eventually reaching zero
Savannah River Site radioiodine atmospheric releases and offsite maximum doses
Marter, W.L.
1990-11-01T23:59:59.000Z
Radioisotopes of iodine have been released to the atmosphere from the Savannah River Site since 1955. The releases, mostly from the 200-F and 200-H Chemical Separations areas, consist of the isotopes, I-129 and 1-131. Small amounts of 1-131 and 1-133 have also been released from reactor facilities and the Savannah River Laboratory. This reference memorandum was issued to summarize our current knowledge of releases of radioiodines and resultant maximum offsite doses. This memorandum supplements the reference memorandum by providing more detailed supporting technical information. Doses reported in this memorandum from consumption of the milk containing the highest I-131 concentration following the 1961 1-131 release incident are about 1% higher than reported in the reference memorandum. This is the result of using unrounded 1-131 concentrations of I-131 in milk in this memo. It is emphasized here that this technical report does not constitute a dose reconstruction in the same sense as the dose reconstruction effort currently underway at Hanford. This report uses existing published data for radioiodine releases and existing transport and dosimetry models.
LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL
Don Augenstein
2001-02-01T23:59:59.000Z
The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with conventional landfills. This is the highest methane recovery rate per unit waste, and thus progress toward stabilization, documented anywhere for such a large waste mass. This high recovery rate is attributed to moisture, and elevated temperature attained inexpensively during startup. Economic analyses performed under Phase I of this NETL contract indicate ''greenhouse cost effectiveness'' to be excellent. Other benefits include substantial waste volume loss (over 30%) which translates to extended landfill life. Other environmental benefits include rapidly improved quality and stabilization (lowered pollutant levels) in liquid leachate which drains from the waste.
Maximum Entropy Analysis of the Spectral Functions in Lattice QCD
M. Asakawa; T. Hatsuda; Y. Nakahara
2001-02-26T23:59:59.000Z
First principle calculation of the QCD spectral functions (SPFs) based on the lattice QCD simulations is reviewed. Special emphasis is placed on the Bayesian inference theory and the Maximum Entropy Method (MEM), which is a useful tool to extract SPFs from the imaginary-time correlation functions numerically obtained by the Monte Carlo method. Three important aspects of MEM are (i) it does not require a priori assumptions or parametrizations of SPFs, (ii) for given data, a unique solution is obtained if it exists, and (iii) the statistical significance of the solution can be quantitatively analyzed. The ability of MEM is explicitly demonstrated by using mock data as well as lattice QCD data. When applied to lattice data, MEM correctly reproduces the low-energy resonances and shows the existence of high-energy continuum in hadronic correlation functions. This opens up various possibilities for studying hadronic properties in QCD beyond the conventional way of analyzing the lattice data. Future problems to be studied by MEM in lattice QCD are also summarized.
Improved Maximum Entropy Method with an Extended Search Space
Alexander Rothkopf
2012-08-25T23:59:59.000Z
We report on an improvement to the implementation of the Maximum Entropy Method (MEM). It amounts to departing from the search space obtained through a singular value decomposition (SVD) of the Kernel. Based on the shape of the SVD basis functions we argue that the MEM spectrum for given $N_\\tau$ data-points $D(\\tau)$ and prior information $m(\\omega)$ does not in general lie in this $N_\\tau$ dimensional singular subspace. Systematically extending the search basis will eventually recover the full search space and the correct extremum. We illustrate this idea through a mock data analysis inspired by actual lattice spectra, to show where our improvement becomes essential for the success of the MEM. To remedy the shortcomings of Bryan's SVD prescription we propose to use the real Fourier basis, which consists of trigonometric functions. Not only does our approach lead to more stable numerical behavior, as the SVD is not required for the determination of the basis functions, but also the resolution of the MEM becomes independent from the position of the reconstructed peaks.
Maximum entropy detection of planets around active stars
Petit, P; Hébrard, E; Morin, J; Folsom, C P; Böhm, T; Boisse, I; Borgniet, S; Bouvier, J; Delfosse, X; Hussain, G; Jeffers, S V; Marsden, S C; Barnes, J R
2015-01-01T23:59:59.000Z
(shortened for arXiv) We aim to progress towards more efficient exoplanet detection around active stars by optimizing the use of Doppler Imaging in radial velocity measurements. We propose a simple method to simultaneously extract a brightness map and a set of orbital parameters through a tomographic inversion technique derived from classical Doppler mapping. Based on the maximum entropy principle, the underlying idea is to determine the set of orbital parameters that minimizes the information content of the resulting Doppler map. We carry out a set of numerical simulations to perform a preliminary assessment of the robustness of our method, using an actual Doppler map of the very active star HR 1099 to produce a realistic synthetic data set for various sets of orbital parameters of a single planet in a circular orbit. Using a simulated time-series of 50 line profiles affected by a peak-to-peak activity jitter of 2.5 km/s, we are able in most cases to recover the radial velocity amplitude, orbital phase and o...
Maximum Power Point Tracking Control for Photovoltaic System Using Adaptive Neuro-Fuzzy
Paris-Sud XI, Université de
Maximum Power Point Tracking Control for Photovoltaic System Using Adaptive Neuro- Fuzzy "ANFIS energy demand. The mathematical modeling and simulation of the photovoltaic system is implemented) like ANFIS. This paper presents Maximum Power Point Tracking Control for Photovoltaic System Using
A Maximum Entropy Algorithm for Rhythmic Analysis of Genome-Wide Expression Patterns
Richardson, David
A Maximum Entropy Algorithm for Rhythmic Analysis of Genome-Wide Expression Patterns Christopher James Langmead C. Robertson McClung Bruce Randall Donald ,,,Â§,Â¶ Abstract We introduce a maximum entropy-based spectral analysis, maximum entropy spectral reconstruction is well suited to signals of the type generated
1 A MAXIMUM ENTROPY METHOD FOR SUBNETWORK ORIGIN-DESTINATION 2 TRIP MATRIX ESTIMATION
Kockelman, Kara M.
1 A MAXIMUM ENTROPY METHOD FOR SUBNETWORK ORIGIN-DESTINATION 2 TRIP MATRIX ESTIMATION 3 4 Chi Xie 5, maximum entropy, linearization 36 algorithm, column generation 37 #12;C. Xie, K.M. Kockelman and S is the trip matrix of the simplified network. This paper discusses a5 maximum entropy method
Maximum entropy and Bayesian approaches to the ratio problem Edward Z. Shen*
Perloff, Jeffrey M.
Maximum entropy and Bayesian approaches to the ratio problem Edward Z. Shen* Jeffrey M. Perloff** January 2001 Abstract Maximum entropy and Bayesian approaches provide superior estimates of a ratio extra information in the supports for the underlying parameters for generalized maximum entropy (GME
Perloff, Jeffrey M.
Comparison of Maximum Entropy and Higher-Order Entropy Estimators Amos Golan* and Jeffrey M. Perloff** ABSTRACT We show that the generalized maximum entropy (GME) is the only estimation method- classes of estimators may outperform the GME estimation rule. Keywords: generalized entropy, maximum
A maximum entropy-least squares estimator for elastic origin-destination trip matrix estimation
Kockelman, Kara M.
A maximum entropy-least squares estimator for elastic origin- destination trip matrix estimation propose a combined maximum entropy-least squares (ME-LS) estimator, by which O- D flows are distributed-destination trip table; elastic demand; maximum entropy; least squares; subnetwork analysis; convex combination
Marsh, S.P.
1988-03-08T23:59:59.000Z
An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.
Marsh, S.P.
1987-03-12T23:59:59.000Z
An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.
Graham, T. B.
2010-04-01T23:59:59.000Z
The IR Hot Wave{trademark} furnace is a breakthrough heat treatment system for manufacturing metal components. Near-infrared (IR) radiant energy combines with IR convective heating for heat treating. Heat treatment is an essential process in the manufacture of most components. The controlled heating and cooling of a metal or metal alloy alters its physical, mechanical, and sometimes chemical properties without changing the object's shape. The IR Hot Wave{trademark} furnace offers the simplest, quickest, most efficient, and cost-effective heat treatment option for metals and metal alloys. Compared with other heat treatment alternatives, the IR Hot Wave{trademark} system: (1) is 3 to 15 times faster; (2) is 2 to 3 times more energy efficient; (3) is 20% to 50% more cost-effective; (4) has a {+-}1 C thermal profile compared to a {+-}10 C thermal profile for conventional gas furnaces; and (5) has a 25% to 50% smaller footprint.
Lucas, Timothy S. (4614 River Mill Ct., Glen Allen, VA 23060)
1991-01-01T23:59:59.000Z
A compressor for compression-evaporation cooling systems, which requires no moving parts. A gaseous refrigerant inside a chamber is acoustically compressed and conveyed by means of a standing acoustic wave which is set up in the gaseous refrigerant. This standing acoustic wave can be driven either by a transducer, or by direct exposure of the gas to microwave and infrared sources, including solar energy. Input and output ports arranged along the chamber provide for the intake and discharge of the gaseous refrigerant. These ports can be provided with optional valve arrangements, so as to increase the compressor's pressure differential. The performance of the compressor in either of its transducer or electromagnetically driven configurations, can be optimized by a controlling circuit. This controlling circuit holds the wavelength of the standing acoustical wave constant, by changing the driving frequency in response to varying operating conditions.
Yerganian, Simon Scott (Lee's Summit, MO)
2003-02-11T23:59:59.000Z
A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase-shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in the direction of an imposed electric field, generally referred to as the d.sub.33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.
Yerganian, Simon Scott (Lee's Summit, MO)
2001-07-17T23:59:59.000Z
A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in direction of an imposed electric field, generally referred to as the d.sub.33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.
WAVE PIPELINES VIA LOOK-UP TABLES Eduardo I. Boemo, Sergio L6pez-Buedo, and Juan M. A4eneses
Boemo, Eduardo
block for the construction of wave pipelined circuits. In this paper, this alternative is explored The construction of maximum-rate circuits or wave pipelines is centered on the equalization of all path delays pipeline topics: LUTS mask the delay of different logic functions, and also have been designed as data
Adaptive multiconfigurational wave functions
Evangelista, Francesco A., E-mail: francesco.evangelista@emory.edu [Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322 (United States)
2014-03-28T23:59:59.000Z
A method is suggested to build simple multiconfigurational wave functions specified uniquely by an energy cutoff ?. These are constructed from a model space containing determinants with energy relative to that of the most stable determinant no greater than ?. The resulting ?-CI wave function is adaptive, being able to represent both single-reference and multireference electronic states. We also consider a more compact wave function parameterization (?+SD-CI), which is based on a small ?-CI reference and adds a selection of all the singly and doubly excited determinants generated from it. We report two heuristic algorithms to build ?-CI wave functions. The first is based on an approximate prescreening of the full configuration interaction space, while the second performs a breadth-first search coupled with pruning. The ?-CI and ?+SD-CI approaches are used to compute the dissociation curve of N{sub 2} and the potential energy curves for the first three singlet states of C{sub 2}. Special attention is paid to the issue of energy discontinuities caused by changes in the size of the ?-CI wave function along the potential energy curve. This problem is shown to be solvable by smoothing the matrix elements of the Hamiltonian. Our last example, involving the Cu{sub 2}O{sub 2}{sup 2+} core, illustrates an alternative use of the ?-CI method: as a tool to both estimate the multireference character of a wave function and to create a compact model space to be used in subsequent high-level multireference coupled cluster computations.
LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL
Don Augenstein; Ramin Yazdani; Rick Moore; Michelle Byars; Jeff Kieffer; Professor Morton Barlaz; Rinav Mehta
2000-02-26T23:59:59.000Z
Controlled landfilling is an approach to manage solid waste landfills, so as to rapidly complete methane generation, while maximizing gas capture and minimizing the usual emissions of methane to the atmosphere. With controlled landfilling, methane generation is accelerated to more rapid and earlier completion to full potential by improving conditions (principally moisture, but also temperature) to optimize biological processes occurring within the landfill. Gas is contained through use of surface membrane cover. Gas is captured via porous layers, under the cover, operated at slight vacuum. A field demonstration project has been ongoing under NETL sponsorship for the past several years near Davis, CA. Results have been extremely encouraging. Two major benefits of the technology are reduction of landfill methane emissions to minuscule levels, and the recovery of greater amounts of landfill methane energy in much shorter times, more predictably, than with conventional landfill practice. With the large amount of US landfill methane generated, and greenhouse potency of methane, better landfill methane control can play a substantial role both in reduction of US greenhouse gas emissions and in US renewable energy. The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with conventional landfills. This is the highest methane recovery rate per unit waste, and thus progress toward stabilization, documented anywhere for such a large waste mass. This high recovery rate is attributed to moisture, and elevated temperature attained inexpensively during startup. Economic analyses performed under Phase I of this NETL contract indicate ''greenhouse cost effectiveness'' to be excellent. Other benefits include substantial waste volume loss (over 30%) which translates to extended landfill life. Other environmental benefits include rapidly improved quality and stabilization (lowered pollutant levels) in liquid leachate which drains from the waste.
Real-time Water Waves with Wave Particles
Yuksel, Cem
2010-10-12T23:59:59.000Z
This dissertation describes the wave particles technique for simulating water surface waves and two way fluid-object interactions for real-time applications, such as video games. Water exists in various different forms in our environment...
Propagation of seismic waves through liquefied soils
Taiebat, Mahdi; Jeremic, Boris; Dafalias, Yannis; Kaynia, Amir; Cheng, Zhao
2010-01-01T23:59:59.000Z
the mechanisms of wave propagation and ARTICLE IN PRESS M.Numerical analysis Wave propagation Earthquake Liquefactionenergy during any wave propagation. This paper summarizes
California Small Hydropower and Ocean Wave Energy
California Small Hydropower and Ocean Wave Energy Resources IN SUPPORT OF THE 2005 INTEGRATED....................................................................................................................... 9 Ocean Wave Energy............................................................................................................. 20 Wave Energy Conversion Technology
mm-Wave Phase Shifters and Switches
Adabi Firouzjaei, Ehsan
2010-01-01T23:59:59.000Z
4.1.1 Slow wave transmissioncombiners . . . . . . . . . . . 5.3 mm-Wave implementationfailed to predict current mm-wave design trend [1] . . . . .
Heat Waves, Global Warming, and Mitigation
Carlson, Ann E.
2008-01-01T23:59:59.000Z
Heat Waves, Global Warming, and Mitigation Ann E. Carlson*2008]HEAT WAVES, GLOBAL WARMING, AND MITIGATION 175 stroke2001). 2008]HEAT WAVES, GLOBAL WARMING, AND MITIGATION 177
Timothy H. Boyer
2002-10-30T23:59:59.000Z
By numerical calculation, the Planck spectrum with zero-point radiation is shown to satisfy a natural maximum-entropy principle whereas alternative choices of spectra do not. Specifically, if we consider a set of conducting-walled boxes, each with a partition placed at a different location in the box, so that across the collection of boxes the partitions are uniformly spaced across the volume, then the Planck spectrum correspond to that spectrum of random radiation (having constant energy kT per normal mode at low frequencies and zero-point energy (1/2)hw per normal mode at high frequencies) which gives maximum uniformity across the collection of boxes for the radiation energy per box. The analysis involves Casimir energies and zero-point radiation which do not usually appear in thermodynamic analyses. For simplicity, the analysis is presented for waves in one space dimension.
Wave refraction and wave energy on Cayo Arenas
Walsh, Donald Eugene
1962-01-01T23:59:59.000Z
WAVE REFRACTION AND WAVE ENERGY ON CAYO ARENAS A Thesis By Donald E. Welsh Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... January 1962 Major Subject: Physical Oceanography WAVE REFRACTION AND WAVE ENERGY ON CAYO ARENAS A Thesis Donald E. Walsh Approved as to style and content by: Chairman of the Committee ead of Department ' / January 1962 ACKNOWLEDGMENTS...
Menikoff, Ralph [Los Alamos National Laboratory
2012-04-03T23:59:59.000Z
Shock initiation in a plastic-bonded explosives (PBX) is due to hot spots. Current reactive burn models are based, at least heuristically, on the ignition and growth concept. The ignition phase occurs when a small localized region of high temperature (or hot spot) burns on a fast time scale. This is followed by a growth phase in which a reactive front spreads out from the hot spot. Propagating reactive fronts are deflagration waves. A key question is the deflagration speed in a PBX compressed and heated by a shock wave that generated the hot spot. Here, the ODEs for a steady deflagration wave profile in a compressible fluid are derived, along with the needed thermodynamic quantities of realistic equations of state corresponding to the reactants and products of a PBX. The properties of the wave profile equations are analyzed and an algorithm is derived for computing the deflagration speed. As an illustrative example, the algorithm is applied to compute the deflagration speed in shock compressed PBX 9501 as a function of shock pressure. The calculated deflagration speed, even at the CJ pressure, is low compared to the detonation speed. The implication of this are briefly discussed.
Rossen I. Ivanov
2007-07-12T23:59:59.000Z
The Euler's equations describe the motion of inviscid fluid. In the case of shallow water, when a perturbative asymtotic expansion of the Euler's equations is taken (to a certain order of smallness of the scale parameters), relations to certain integrable equations emerge. Some recent results concerning the use of integrable equation in modeling the motion of shallow water waves are reviewed in this contribution.
Magnetohydrodynamic Shearing Waves
Bryan M. Johnson
2007-02-12T23:59:59.000Z
I consider the nonaxisymmetric linear theory of a rotating, isothermal magnetohydrodynamic (MHD) shear flow. The analysis is performed in the shearing box, a local model of a thin disk, using a decomposition in terms of shearing waves, i.e., plane waves in a frame comoving with the shear. These waves do not have a definite frequency as in a normal mode decomposition, and numerical integration of a coupled set of amplitude equations is required to characterize their time dependence. Their generic time dependence, however, is oscillatory with slowly-varying frequency and amplitude, and one can construct accurate analytical solutions by applying the Wentzel-Kramers-Brillouin method to the full set of amplitude equations. The solutions have the following properties: 1) Their accuracy increases with wavenumber, so that most perturbations that fit within the disk are well-approximated as modes with time-dependent frequencies and amplitudes. 2) They can be broadly classed as incompressive and compressive perturbations, the former including the nonaxisymmetric extension of magnetorotationally unstable modes, and the latter being the extension of fast and slow modes to a differentially-rotating medium. 3) Wave action is conserved, implying that their energy varies with frequency. 4) Their shear stress is proportional to the slope of their frequency, so that they transport angular momentum outward (inward) when their frequency increases (decreases). The complete set of solutions constitutes a comprehensive linear test suite for numerical MHD algorithms that incorporate a background shear flow. I conclude with a brief discussion of possible astrophysical applications.
CHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland
Haller, Merrick
CHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland ABSTRACT Ocean Wave Energy Converters (OWECs) operating on the water surface are subject to storms at station 139. Keywords: wave energy, survivability, breaking waves, joint distribution, OWEC INTRODUCTION
Bulk Energization of Electrons in Solar Flares by Alfv\\'en Waves
Melrose, D B
2013-01-01T23:59:59.000Z
Bulk energization of electrons to $10\\,-\\,20\\,$keV in solar flares is attributed to dissipation of Alfv\\'en waves that transport energy and potential downward to an acceleration region near the chromosphere. The acceleration involves the parallel electric field that develops in the limit of inertial Alfv\\'en waves (IAWs). A two-potential model for IAWs is used to relate the parallel potential to the cross-field potential transported by the waves. We identify a maximum parallel potential in terms of a maximum current density that corresponds to the threshold for the onset of anomalous resistivity. This maximum is of order $10\\,$kV when the threshold is that for the Buneman instability. We argue that this restricts the cross-field potential in an Alfv\\'en wave to about $10\\,$kV. Effective dissipation requires a large number of up- and down-current paths associated with multiple Alfv\\'en waves. The electron acceleration occurs in localized, transient, anomalously-conducting regions (LTACRs) and is associated wit...
Gas Explosion Characterization, Wave Propagation
s & Dt^boooo^j RisÃ¸-R-525 Gas Explosion Characterization, Wave Propagation (Small-Scale Experiments EXPLOSION CHARACTERIZATION, WAVE PROPAGATION (Small-Scale Experiments) G.C. Larsen Abstract. A number characteristics 14 3.5. Characteristics of the primary pressure wave 21 3.6. Pressure propagation over a hard
2, 70177025, 2014 Freaque wave
NHESSD 2, 70177025, 2014 Freaque wave occurrences in 2013 P. C. Liu Title Page Abstract to the corresponding final paper in NHESS if available. Brief Communication: Freaque wave occurrences in 2013 P. C. Liu7025, 2014 Freaque wave occurrences in 2013 P. C. Liu Title Page Abstract Introduction Conclusions References
Karney, Charles
is an envelope solitary wave. These solitary waves are not solitons. The occurrence of the constant phase pulses-state propagation of one of the two lower hybrid rays in a homogeneous considering the balance between thermal break up into two types of solitary waves, constant phase pulses or envelope pulses. e examine
Microstructural Design for Stress Wave Energy Management /
Tehranian, Aref
2013-01-01T23:59:59.000Z
Nemat-Nasser, Stress-wave energy management through materialNasser, S. , 2010. Stress-wave energy management throughconstitute pressure wave energy and/or shear wave energy.
Craig, Walter
Introduction Modeling of large ocean waves Propagation speed Coherent wavetrains Near-shore wave waves #12;Introduction Modeling of large ocean waves Propagation speed Coherent wavetrains NearMaster University Tsunamis and ocean waves #12;Introduction Modeling of large ocean waves Propagation speed Coherent
Wave dynamics in a sunspot umbra
Sych, R
2014-01-01T23:59:59.000Z
The high spatial and time resolution data obtained with SDO/AIA for the sunspot in active region NOAA 11131 on 08 December 2010 were analysed with the time-distance plot technique and the pixelised wavelet filtering method. Oscillations in the 3 min band dominate in the umbra. The integrated spectrum of umbral oscillations contains distinct narrowband peaks at 1.9 min, 2.3 min, and 2.8 min. The power significantly varies in time, forming distinct oscillation trains. The oscillation power distribution over the sunspot in the horizontal plane reveals that the enhancements of the oscillation amplitude, or wave fronts, have a distinct structure consisting of an evolving two-armed spiral and a stationary circular patch at the spiral origin, situated near the umbra centre. This structure is seen from the temperature minimum to the corona. In time, the spiral rotates anti-clockwise. The wave front spirality is most pronounced during the maximum amplitude phases of the oscillations. In the low-amplitude phases the sp...
Nonlinear Hysteretic Torsional Waves
J. Cabaret; P. Béquin; G. Theocharis; V. Andreev; V. E. Gusev; V. Tournat
2015-01-09T23:59:59.000Z
We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities, and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other type of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short term memory as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control devices such as strong amplitude-dependent filters.
Nonlinear Hysteretic Torsional Waves
Cabaret, J; Theocharis, G; Andreev, V; Gusev, V E; Tournat, V
2015-01-01T23:59:59.000Z
We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities, and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other type of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short term memory as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control de...
L. Montagnier; J. Aissa; E. Del Giudice; C. Lavallee; A. Tedeschi; G. Vitiello
2010-12-23T23:59:59.000Z
Some bacterial and viral DNA sequences have been found to induce low frequency electromagnetic waves in high aqueous dilutions. This phenomenon appears to be triggered by the ambient electromagnetic background of very low frequency. We discuss this phenomenon in the framework of quantum field theory. A scheme able to account for the observations is proposed. The reported phenomenon could allow to develop highly sensitive detection systems for chronic bacterial and viral infections.
Zi-Niu Wu
2013-10-02T23:59:59.000Z
For many natural process of growth, with the growth rate independent of size due to Gibrat law and with the growth process following a log-normal distribution, the ratio between the time (D) for maximum value and the time (L) for maximum growth rate (inflexion point) is then equal to the square root of the base of the natural logarithm (e^{1/2}). On the logarithm scale this ratio becomes one half ((1/2)). It remains an open question, due to lack of complete data for various cases with restricted growth, whether this e^{1/2} ratio can be stated as e^{1/2}-Law. Two established examples already published, one for an epidemic spreading and one for droplet production, support however this ratio. Another example appears to be the height of humain body. For boys the maximum height occurs near 23 years old while the maximum growth rate is at the age near 14, and there ratio is close to e^{1/2}. The main theoretical base to obtain this conclusion is problem independent, provided the growth process is restricted, such as public intervention to control the spreading of communicable epidemics, so that an entropy is associated with the process and the role of dissipation, representing the mechanism of intervention, is maximized. Under this formulation the principle of maximum rate of entropy production is used to make the production process problem independent.
Nondestructive testing using stress waves: wave propagation in layered media
Ortega, Jose Alberto
2013-02-22T23:59:59.000Z
NONDESTRUCTIVE TESTING USING STRESS WAVES: WAVE PROPAGATION IN LAYERED MEDIA A Senior Honors Thesis by JOSE ALBERTO ORTEGA Submitted to the Office of Honors Program & Academic Scholarships Texas A&M University in partial fulfillment... of the requirement of the UNIVERSITY UNDERGRADUATE RESEARCH FELLOWS April 2002 Group: Engineering NONDESTRUCTIVE TESTING USI WAVE PROPAGATION IN LA A Senior Honors The ~pe -C JOSE ALBERTO ORTI /CI Submitted to the Office of Honors Program k. Academic...
Use of Two Distillation Columns in Systems with Maximum Temperature Limitations
Gilchrist, James F.
Use of Two Distillation Columns in Systems with Maximum Temperature Limitations Rebecca H. Masel, Pennsylvania 18015, United States ABSTRACT: Maximum temperature limitations are encountered in distillation of the bottoms product fixes the column base pressure and, hence, the condenser pressure. The distillate
Maximum Power Transfer Tracking in a Solar USB Charger for Smartphones
Pedram, Massoud
chargers do not perform the maximum power point tracking [2], [3] of the solar panel. We excludeMaximum Power Transfer Tracking in a Solar USB Charger for Smartphones Abstract--Battery life poor capacity utilization during solar energy harvesting. In this paper, we propose and demonstrate
Wang, Yuqing
Energy Production, Frictional Dissipation, and Maximum Intensity of a Numerically Simulated is eventually dissipated due to surface friction. Since the energy production rate is a linear function while frictional dissipation rate balances the energy production rate near the radius of maximum wind (RMW
Wang, Yuqing
0 Energy Production, Frictional Dissipation, and Maximum Intensity of a Numerically Simulated is eventually dissipated due to surface friction. Since the energy production rate is a linear function while frictional dissipation rate balances the energy production rate near the radius of maximum wind (RMW
Efficiency at maximum power of low dissipation Carnot engines Massimiliano Esposito
Kawai, Ryoichi
Efficiency at maximum power of low dissipation Carnot engines Massimiliano Esposito Center the efficiency at maximum power, , of engines performing finite-time Carnot cycles between a hot and a cold reservoir at temperatures Th and Tc, respectively. For engines reaching Carnot efficiency C = 1 - Tc
Osterloh, Frank
Maximum Theoretical Efficiency Limit of Photovoltaic Devices: Effect of Band Structure on Excited a theoretical limit for the maximum energy conversion efficiency of single junction photovoltaic cells for the efficiency variations observed for real photovoltaic devices today.4-6 Here, we show that the extractable
Maximum-Power-Point Tracking Method of Photovoltaic Using Only Single Current Sensor
Fujimoto, Hiroshi
» «Solar cell systems» Abstract This paper describes a novel strategy of maximum-power-point tracking point using only a single current sensor, i.e., a Hall-effect CT. Output power of the photovoltaic can-climbing method is employed to seek the maximum power point, using the output power obtained from only the current
Ranade, Abhiram G.
An Improved Maximum Likelihood Formulation for Accurate Genome Assembly Aditya Varma, Abhiram maximum likelihood method for genome assembly. We formulate the problem as one of direct convex estimate of the length of the genome or the need to use further expectation minimization to predict
How Is the Maximum Entropy of a Quantized Surface Related to Its Area?
I. B. Khriplovich; R. V. Korkin
2001-12-27T23:59:59.000Z
The maximum entropy of a quantized surface is demonstrated to be proportional to the surface area in the classical limit. The result is valid in loop quantum gravity, and in a somewhat more general class of approaches to surface quantization. The maximum entropy is calculated explicitly for some specific cases.
Tadi?, Vladislav B
2009-01-01T23:59:59.000Z
This paper considers the asymptotic properties of the recursive maximum likelihood estimation in hidden Markov models. The paper is focused on the asymptotic behavior of the log-likelihood function and on the point-convergence and convergence rate of the recursive maximum likelihood estimator. Using the principle of analytical continuation, the analyticity of the asymptotic log-likelihood function is shown for analytically parameterized hidden Markov models. Relying on this fact and some results from differential geometry (Lojasiewicz inequality), the almost sure point-convergence of the recursive maximum likelihood algorithm is demonstrated, and relatively tight bounds on the convergence rate are derived. As opposed to the existing result on the asymptotic behavior of maximum likelihood estimation in hidden Markov models, the results of this paper are obtained without assuming that the log-likelihood function has an isolated maximum at which the Hessian is strictly negative definite.
Unification of Field Theory and Maximum Entropy Methods for Learning Probability Densities
Kinney, Justin B
2014-01-01T23:59:59.000Z
Bayesian field theory and maximum entropy are two methods for learning smooth probability distributions (a.k.a. probability densities) from finite sampled data. Both methods were inspired by statistical physics, but the relationship between them has remained unclear. Here I show that Bayesian field theory subsumes maximum entropy density estimation. In particular, the most common maximum entropy methods are shown to be limiting cases of Bayesian inference using field theory priors that impose no boundary conditions on candidate densities. This unification provides a natural way to test the validity of the maximum entropy assumption on one's data. It also provides a better-fitting nonparametric density estimate when the maximum entropy assumption is rejected.
Frank G. Borg; Ismo Hakala; Jukka Määttälä
2007-12-24T23:59:59.000Z
We present a summary of the basic properties of the radio wave generation, propagation and reception, with a special attention to the gigahertz bandwidth region which is of interest for wireless sensor networks. We also present some measurement results which use the so-called RSSI indicator in order to track how the field strength varies with position and distance of the transceivers. We hope the paper may be useful to anyone who looks for a quick review of the fundamentals of electromagnetic theory with application to antennas.
Lipscombe, O. J. [University of Tennessee, Knoxville (UTK); Chen, G. F. [The Institute of Physics, Chinese Academy of Sciences; Fang, Chen [Purdue University; Perring, T. G. [ISIS Facility, Rutherford Appleton Laboratory; Abernathy, Douglas L [ORNL; Christianson, Andrew D [ORNL; Egami, Takeshi [ORNL; Wang, Nanlin [The Institute of Physics, Chinese Academy of Sciences; Hu, Jiangping [Purdue University and Chinese Academy of Sciences; Dai, Pengcheng [University of Tennessee, Knoxville (UTK)
2011-01-01T23:59:59.000Z
We use neutron scattering to show that spin waves in the iron chalcogenide Fe{sub 1.05}Te display novel dispersion clearly different from both the first principles density functional calculations and recent observations in the related iron pnictide CaFe{sub 2}As{sub 2}. By fitting to a Heisenberg Hamiltonian, we find that although the nearest-neighbor exchange couplings in the two systems are quite different, their next-nearest-neighbor (NNN) couplings are similar. This suggests that superconductivity in the pnictides and chalcogenides share a common magnetic origin that is intimately associated with the NNN magnetic coupling between the irons.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1DOETHE FUTURE LOOKSof Energy Wave
Fast wave current drive in DIII-D
Petty, C.C.; Callis, R.W.; Chiu, S.C.; deGrassie, J.S.; Forest, C.B.; Freeman, R.L.; Gohil, P.; Harvey, R.W.; Ikezi, H.; Lin-Liu, Y.-R. [and others
1995-02-01T23:59:59.000Z
The non-inductive current drive from fast Alfven waves launched by a directional four-element antenna was measured in the DIII-D tokamak. The fast wave frequency (60 MHz) was eight times the deuterium cyclotron frequency at the plasma center. An array of rf pickup loops at several locations around the torus was used to verify the directivity of the four-element antenna. Complete non-inductive current drive was achieved using a combination of fast wave current drive (FWCD) and electron cyclotron current drive (ECCD) in discharges for which the total plasma current was inductively ramped down from 400 to 170 kA. For discharges with steady plasma current, up to 110 kA of FWCD was inferred from an analysis of the loop voltage, with a maximum non-inductive current (FWCD, ECCD, and bootstrap) of 195 out of 310 kA. The FWCD efficiency increased linearly with central electron temperature. For low current discharges, the FWCD efficiency was degraded due to incomplete fast wave damping. The experimental FWCD was found to agree with predictions from the CURRAY ray-tracing code only when a parasitic loss of 4% per pass was included in the modeling along with multiple pass damping.
Andrey Beresnyak; Alex Lazarian
2008-05-06T23:59:59.000Z
We present a model for nonlinear decay of the weak wave in three-dimensional incompressible magnetohydrodynamic (MHD) turbulence. We show that the decay rate is different for parallel and perpendicular waves. We provide a general formula for arbitrarily directed waves and discuss particular limiting cases known in the literature. We test our predictions with direct numerical simulations of wave decay in three-dimensional MHD turbulence, and discuss the influence of turbulent damping on the development of linear instabilities in the interstellar medium and on other important astrophysical processes.
Electrostatic solitary ion waves in dense electron-positron-ion magnetoplasma
Jehan, Nusrat [Department of Physics, Theoretical Plasma Physics Group, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Pakistan Atomic Energy Commission, P.O. Box 1114, Islamabad 44000 (Pakistan); Salahuddin, M. [Pakistan Atomic Energy Commission, P.O. Box 1114, Islamabad 44000 (Pakistan); Mahmood, S. [Theoretical Plasma Physics Division, PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan); Mirza, Arshad M. [Department of Physics, Theoretical Plasma Physics Group, Quaid-i-Azam University, Islamabad 45320 (Pakistan)
2009-04-15T23:59:59.000Z
The nonlinear coupled ion-acoustic and ion-cyclotron waves propagating obliquely to the external magnetic field in dense collisionless electron-positron-ion magnetoplasma are investigated using Sagdeev potential method. A semiclassical approach is used. Electrons and positrons are treated as degenerate Fermi gases described by Thomas-Fermi density distribution and ions behave as classical gas. It is found that the presence of degenerate positrons in a dense Thomas-Fermi plasma significantly modifies the structure of solitary waves by restricting the electrostatic potential to a certain maximum value which depends upon the concentration of positrons in the system. It is also noted that only subsonic humplike solitary waves can exist and for a given angle of propagation, the presence of degenerate positrons diminishes the amplitude as well as width of the solitary wave.
Wave Evolution On the Evolution of Curvelets
Smith, Hart F.
Curvelets Wave Evolution On the Evolution of Curvelets by the Wave Equation Hart F. Smith of Curvelets by the Wave Equation #12;Curvelets Wave Evolution Curvelets and the Second Dyadic Decomposition Curvelets A curvelet frame {} is a wave packet frame on L2(R2) based on second dyadic decomposition. f
Wave Mechanics and the Fifth Dimension
Paul S. Wesson; James M. Overduin
2013-01-28T23:59:59.000Z
Replacing 4D Minkowski space by 5D canonical space leads to a clearer derivation of the main features of wave mechanics, including the wave function and the velocity of de Broglie waves. Recent tests of wave-particle duality could be adapted to investigate whether de Broglie waves are basically 4D or 5D in nature.
Verma, Kanika; Sajal, Vivek, E-mail: vsajal@rediffmail.com; Varshney, Prateek; Kumar, Ravindra; Sharma, Navneet K. [Department of Physics and Materials Science and Engineering, Jaypee Institute of Information Technology, Noida 201307, UP (India)] [Department of Physics and Materials Science and Engineering, Jaypee Institute of Information Technology, Noida 201307, UP (India)
2014-02-15T23:59:59.000Z
Effects of transverse static magnetic field on stimulated Raman scattering (SRS) of the beat wave excited by two counter-propagating lasers are studied. Two counter-propagating lasers with frequency difference, ?{sub 1}??{sub 2}?2?{sub p}, drive a non resonant space charge beat mode at wave number k{sup ?}{sub 0}?k{sup ?}{sub 1}+k{sup ?}{sub 2} in a plasma, where k{sup ?}{sub 1} and k{sup ?}{sub 2} are wave vectors of lasers having frequencies ?{sub 1} and ?{sub 2}, respectively. The driven beat wave acts as a pump for SRS and excites parametrically a pair of plasma wave (?,k{sup ?}) and side band electromagnetic wave (?{sub 3},k{sup ?}{sub 3}) propagating in the sideward direction in such a way that momentum remains conserved. The growth rate of Raman process is maximum for side scattering at ?{sub s}=?/2 for lower values of applied magnetic field (?1?kG), which can be three fold by applying magnetic field ?5.0?kG. Thus, optimum value of magnetic field can be utilized to achieve maximum electron acceleration in counter propagating geometry of beat wave acceleration by reducing the growth rate of Raman process.
Creating Wave-Focusing Materials
A. G. Ramm
2008-05-16T23:59:59.000Z
Basic ideas for creating wave-focusing materials by injecting small particles in a given material are described. The number of small particles to be injected around any point is calculated. Inverse scattering problem with fixed wavenumber and fixed incident direction of the plane acoustic wave is formulated and solved.
Colliding axisymmetric pp-waves
B. V. Ivanov
1997-10-21T23:59:59.000Z
An exact solution is found describing the collision of axisymmetric pp-waves with M=0. They are impulsive in character and their coordinate singularities become point curvature singularities at the boundaries of the interaction region. The solution is conformally flat. Concrete examples are given, involving an ultrarelativistic black hole against a burst of pure radiation or two colliding beam- like waves.
550 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 28, NO. 3, JUNE 2000 Overmoded GW-Class Surface-Wave
Hassam, Adil
--High-power microwave (HPM), overmoded, sur- face-wave oscillator. I. INTRODUCTION APPLICATIONS of high-power microwave (HPM) devices capable of generating gigawatt (GW) levels of output power at centimeter wavelengths of electronic systems. However, the maximum peak-power handling capability of HPM sources is severely limited
Fully nonlinear wave-current interactions and kinematics by a BEM-based numerical wave tank
Lynett, Patrick
Fully nonlinear wave-current interactions and kinematics by a BEM-based numerical wave tank S. Ryu and the resulting kinematics. In the present paper, the variation of wave amplitude and wave length and minimize wave reflections from the down- stream wall. Nonlinear wave kinematics as a result of nonlinear
Korneev, Valeri A. (Lafayette, CA); Bakulin, Andrey (Houston, TX)
2009-10-13T23:59:59.000Z
The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.
Korneev, Valeri A [LaFayette, CA
2009-05-05T23:59:59.000Z
The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.
2011 Interference -1 INTERFERENCE OF SOUND WAVES
Glashausser, Charles
2011 Interference - 1 INTERFERENCE OF SOUND WAVES The objectives of this experiment are: Â· To measure the wavelength, frequency, and propagation speed of ultrasonic sound waves. Â· To observe interference phenomena with ultrasonic sound waves. APPARATUS: Oscilloscope, function generator, ultrasonic
Electrostatic-plasma-wave energy flux
Amendt, P.; Rostoker, N.
1984-01-01T23:59:59.000Z
would reduce cross- field wave-energy convection since theor cross-field leakage of wave energy are ap- that thecomposition of electrostatic-wave-energy field degrees of
Atlantic Ocean circulation at the last glacial maximum : inferences from data and models
Dail, Holly Janine
2012-01-01T23:59:59.000Z
This thesis focuses on ocean circulation and atmospheric forcing in the Atlantic Ocean at the Last Glacial Maximum (LGM, 18-21 thousand years before present). Relative to the pre-industrial climate, LGM atmospheric CO? ...
Tropical climate variability from the last glacial maximum to the present
Dahl, Kristina Ariel
2005-01-01T23:59:59.000Z
This thesis evaluates the nature and magnitude of tropical climate variability from the Last Glacial Maximum to the present. The temporal variability of two specific tropical climate phenomena is examined. The first is the ...
Investigating the angle or response and maximum stability of a cohesive granular pile
Nowak, Sara Alice, 1982-
2004-01-01T23:59:59.000Z
In this thesis, I investigate the static and dynamic properties of a granular heap made cohesive by an interstitial fluid. I present the results of experimental work measuring the maximum angle of stability and the angle ...
Dynamical Reconstruction of Upper-Ocean Conditions in the Last Glacial Maximum Atlantic
Wunsch, Carl
Proxies indicate that the Last Glacial Maximum (LGM) Atlantic Ocean was marked by increased meridional and zonal near sea surface temperature gradients relative to today. Using a least squares fit of a full general circulation ...
Achieving Consistent Maximum Brake Torque with Varied Injection Timing in a DI Diesel Engine
Kroeger, Timothy H
2013-09-19T23:59:59.000Z
, revealing the premixed and diffusion burn fractions as well as important engine and exhaust design criteria such as maximum in-cylinder pressure and exhaust composition. These results are significant in diesel engine design because cheaper, lighter engines...
Microcontroller Servomotor for Maximum Effective Power Point for Solar Cell System
Al-Khalidy, M.; Al-Rawi, O.; Noaman, N.
2010-01-01T23:59:59.000Z
In this paper a Maximum Power point (MPP) tracking algorithm is developed using dual-axis servomotor feedback tracking control system. An efficient and accurate servomotor system is used to increase the system efficiency ...
Submodule Integrated Distributed Maximum Power Point Tracking for Solar Photovoltaic Applications
Pilawa-Podgurski, Robert C. N.
This paper explores the benefits of distributed power electronics in solar photovoltaic applications through the use of submodule integrated maximum power point trackers (MPPT). We propose a system architecture that provides ...
Author's personal copy Unified behaviour of maximum soot yields of methane, ethane and propane
Gülder, Ömer L.
Author's personal copy Unified behaviour of maximum soot yields of methane, ethane and propane the current study and the previous measurements in similar flames with methane, ethane, and propane flames
Microcontroller Servomotor for Maximum Effective Power Point for Solar Cell System
Al-Khalidy, M.; Al-Rawi, O.; Noaman, N.
2010-01-01T23:59:59.000Z
In this paper a Maximum Power point (MPP) tracking algorithm is developed using dual-axis servomotor feedback tracking control system. An efficient and accurate servomotor system is used to increase the system efficiency and reduces the solar cell...
Maximum Network Lifetime in Wireless Sensor Networks with Adjustable Sensing Ranges
Wu, Jie
1 Maximum Network Lifetime in Wireless Sensor Networks with Adjustable Sensing Ranges Mihaela problem in wireless sensor networks with adjustable sensing range. Communication and sensing consume Wireless sensor networks (WSNs) constitute the foundation of a broad range of applications related
A more efficient formulation for computation of the maximum loading points in electric power systems
Chiang, H.D. [Cornell Univ., Ithaca, NY (United States). School of Electrical Engineering; Jean-Jumeau, R. [Electricite d`Haita, Port-au-Prince (Haiti)
1995-05-01T23:59:59.000Z
This paper presents a more efficient formulation for computation of the maximum loading points. A distinguishing feature of the new formulation is that it is of dimension (n + 1), instead of the existing formulation of dimension (2n + 1), for n-dimensional load flow equations. This feature makes computation of the maximum loading points very inexpensive in comparison with those required in the existing formulation. A theoretical basis for the new formulation is provided. The new problem formulation is derived by using a simple reparameterization scheme and exploiting the special properties of the power flow model. Moreover, the proposed test function is shown to be monotonic in the vicinity of a maximum loading point. Therefore, it allows one to monitor the approach to maximum loading points during the solution search process. Simulation results on a 234-bus system are presented.
Acoustic Space Dimensionality Selection and Combination using the Maximum Entropy Principle
Abdel-Haleem, Yasser H; Renals, Steve; Lawrence, Neil D
2004-01-01T23:59:59.000Z
In this paper we propose a discriminative approach to acoustic space dimensionality selection based on maximum entropy modelling. We form a set of constraints by composing the acoustic space with the space of phone classes, and use a continuous...
An Analysis of Maximum Residential Energy Efficiency in Hot and Humid Climates
Malhotra, M.; Haberl, J. S.
2006-01-01T23:59:59.000Z
Systems in Hot and Humid Climates, Orlando, Florida, July 24-26, 2006 Methodology 1. Development of the Basecase Simulation Model 2. Analysis of Energy Saving Measures 3. Development of the Maximum Energy-Efficient House 4. Economic Analysis DOE-2 Input...AN ANALYSIS OF MAXIMUM RESIDENTIAL ENERGY EFFICIENCY IN HOT AND HUMID CLIMATES Mini Malhotra Graduate Research Assistant Jeff Haberl, Ph.D., P.E. Professor/Associate Director Energy Systems Laboratory, Texas A&M University College...
ON THE PROBLEM OF UNIQUENESS FOR THE MAXIMUM STIRLING NUMBER(S) OF THE SECOND KIND
Pomerance, Carl
ON THE PROBLEM OF UNIQUENESS FOR THE MAXIMUM STIRLING NUMBER(S) OF THE SECOND KIND E. Rodney Say that an integer n is exceptional if the maximum Stirling number of the second kind S(n, k) occurs or equal to x is O(x3/5+ ), for any > 0. 1. Introduction Let S(n, k) be the Stirling number of the second
A stochastic model for sediment yield using the Principle of Maximum Entropy
Singh, V. P.; Krstanovic, P. F.
WATER RESOURCES RESEARCH, VOL. 23, NO. 5, PAGES 781-793, MAY 1987 A Stochastic Model for Sediment Yield Using the Principle of Maximum Entropy V. P. SINGH AND P. F. KRSTANOVIC Department of Civil Engineering, Louisiana State University, Baton... Rouge The principle of maximum entropy was applied to derive a stochastic model for sediment yield from upland watersheds. By maximizing the conditional entropy subject to certain constraints, a probability distribution of sediment yield conditioned...
Mapping and Assessment of the United States Ocean Wave Energy Resource
Paul T. Jacobson; George Hagerman; George Scott
2011-12-01T23:59:59.000Z
This project estimates the naturally available and technically recoverable U.S. wave energy resources, using a 51-month Wavewatch III hindcast database developed especially for this study by National Oceanographic and Atmospheric AdministrationÃ?Â¢Ã?Â?Ã?Â?s (NOAAÃ?Â¢Ã?Â?Ã?Â?s) National Centers for Environmental Prediction. For total resource estimation, wave power density in terms of kilowatts per meter is aggregated across a unit diameter circle. This approach is fully consistent with accepted global practice and includes the resource made available by the lateral transfer of wave energy along wave crests, which enables wave diffraction to substantially reestablish wave power densities within a few kilometers of a linear array, even for fixed terminator devices. The total available wave energy resource along the U.S. continental shelf edge, based on accumulating unit circle wave power densities, is estimated to be 2,640 TWh/yr, broken down as follows: 590 TWh/yr for the West Coast, 240 TWh/yr for the East Coast, 80 TWh/yr for the Gulf of Mexico, 1570 TWh/yr for Alaska, 130 TWh/yr for Hawaii, and 30 TWh/yr for Puerto Rico. The total recoverable wave energy resource, as constrained by an array capacity packing density of 15 megawatts per kilometer of coastline, with a 100-fold operating range between threshold and maximum operating conditions in terms of input wave power density available to such arrays, yields a total recoverable resource along the U.S. continental shelf edge of 1,170 TWh/yr, broken down as follows: 250 TWh/yr for the West Coast, 160 TWh/yr for the East Coast, 60 TWh/yr for the Gulf of Mexico, 620 TWh/yr for Alaska, 80 TWh/yr for Hawaii, and 20 TWh/yr for Puerto Rico.
Walking Wave as a Model of Particle
A. V. Goryunov
2012-05-02T23:59:59.000Z
The concept of walking wave is introduced from classical relativistic positions. One- and three-dimensional walking waves considered with their wave equations and dispersion equations. It is shown that wave characteristics (de Broglie's and Compton's wavelengths) and corpuscular characteristics (energy-momentum vector and the rest mass) of particle may be expressed through parameters of walking wave. By that the new view on a number concepts of physic related with wave-particle duality is suggested.
Kim, Leonard, E-mail: kimlh@umdnj.edu [Department of Radiation Oncology, Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ (United States); Narra, Venkat; Yue, Ning [Department of Radiation Oncology, Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ (United States)
2013-07-01T23:59:59.000Z
Recent studies have reported potentially clinically meaningful dose differences when heterogeneity correction is used in breast balloon brachytherapy. In this study, we report on the relationship between heterogeneity-corrected and -uncorrected doses for 2 commonly used plan evaluation metrics: maximum point dose to skin surface and maximum point dose to ribs. Maximum point doses to skin surface and ribs were calculated using TG-43 and Varian Acuros for 20 patients treated with breast balloon brachytherapy. The results were plotted against each other and fit with a zero-intercept line. Max skin dose (Acuros) = max skin dose (TG-43) ? 0.930 (R{sup 2} = 0.995). The average magnitude of difference from this relationship was 1.1% (max 2.8%). Max rib dose (Acuros) = max rib dose (TG-43) ? 0.955 (R{sup 2} = 0.9995). The average magnitude of difference from this relationship was 0.7% (max 1.6%). Heterogeneity-corrected maximum point doses to the skin surface and ribs were proportional to TG-43-calculated doses. The average deviation from proportionality was 1%. The proportional relationship suggests that a different metric other than maximum point dose may be needed to obtain a clinical advantage from heterogeneity correction. Alternatively, if maximum point dose continues to be used in recommended limits while incorporating heterogeneity correction, institutions without this capability may be able to accurately estimate these doses by use of a scaling factor.
Sandia National Laboratories: Wave Energy Resource Characterization...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
eECEnergyComputational Modeling & SimulationWave Energy Resource Characterization at US Test Sites Wave Energy Resource Characterization at US Test Sites Sandia Report Presents...
Wave runup on cylinders subject to deep water random waves
Indrebo, Ann Kristin
2001-01-01T23:59:59.000Z
The accurate prediction of wave runup on deepwater offshore platform columns is of great importance for design engineers. Although linear predictive models are commonly used in the design and analysis process, many of the important effects...
Wave Energy Resource Analysis for Use in Wave Energy Conversion
Pastor, J.; Liu, Y.; Dou, Y.
2014-01-01T23:59:59.000Z
the naturally available and technically recoverable resource in a given location. The methodology was developed by the EPRI and uses a modified Gamma spectrum that interoperates hindcast sea state parameter data produced by NOAA's Wave watch III. This Gamma...
Backreacting p-wave Superconductors
Raúl E. Arias; Ignacio Salazar Landea
2013-01-28T23:59:59.000Z
We study the gravitational backreaction of the non-abelian gauge field on the gravity dual to a 2+1 p-wave superconductor. We observe that as in the $p+ip$ system a second order phase transition exists between a superconducting and a normal state. Moreover, we conclude that, below the phase transition temperature $T_c$ the lowest free energy is achieved by the p-wave solution. In order to probe the solution, we compute the holographic entanglement entropy. For both $p$ and $p+ip$ systems the entanglement entropy satisfies an area law. For any given entangling surface, the p-wave superconductor has lower entanglement entropy.
Nonlinear dust acoustic waves and shocks
Merlino, R. L.; Heinrich, J. R.; Hyun, S.-H.; Meyer, J. K. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)
2012-05-15T23:59:59.000Z
We describe experiments on (1) nonlinear dust acoustic waves and (2) dust acoustic shocks performed in a direct current (DC) glow discharge dusty plasma. First, we describe experiments showing nonlinear dust acoustic waves characterized by waveforms of the dust density that are typically sharper in the wave crests and flatter in the wave troughs (compared to sinusoidal waves), indicating the development of wave harmonics. We discuss this behavior in terms of a second-order fluid theory for dust acoustic waves. Second, experimental observations of the propagation and steepening of large-amplitude dust acoustic waves into dust acoustic shock waves are presented. The observed shock wave evolution is compared with numerical calculations based on the Riemann solution of the fully nonlinear fluid equations for dust acoustic waves.
Plasma waves driven by gravitational waves in an expanding universe
D. B. Papadopoulos
2002-05-22T23:59:59.000Z
In a Friedmann-Robertson-Walker (FRW) cosmological model with zero spatial curvature, we consider the interaction of the gravitational waves with the plasma in the presence of a weak magnetic field. Using the relativistic hydromagnetic equations it is verified that large amplitude magnetosonic waves are excited, assuming that both, the gravitational field and the weak magnetic field do not break the homogeneity and isotropy of the considered FRW spacetime.
Wave Energy Extraction from buoys
Garnaud, Xavier
2009-01-01T23:59:59.000Z
Different types of Wave Energy Converters currently tested or under development are using the vertical movement of floating bodies to generate electricity. For commercial applications, arrays have to be considered in order ...
Period-luminosity and period-luminosity-colour relations for Mira variables at maximum light
S. M. Kanbur; M. A. Hendry; D. Clarke
1997-04-14T23:59:59.000Z
In this paper we confirm the existence of period-luminosity (PL) and period-luminosity-colour (PLC) relations at maximum light for O and C Mira variables in the LMC. We demonstrate that in the J and H bands the maximum light PL relations have a significantly smaller dispersion than their counterparts at mean light, while the K band and bolometric PL relations have a dispersion comparable to that at mean light. In the J, H and K bands the fitted PL relations for the O Miras are found to have smaller dispersion than those for the C Miras, at both mean and maximum light, while the converse is true for the relations based on bolometric magnitudes. The inclusion of a non-zero log period term is found to be highly significant in all cases except that of the C Miras in the J band, for which the data are found to be consistent with having constant absolute magnitude. This suggests the possibility of employing C Miras as standard candles. We suggest both a theoretical justification for the existence of Mira PL relations at maximum light and a possible explanation of why these relations should have a smaller dispersion than at mean light. The existence of such maximum light relations offers the possibility of extending the range and improving the accuracy of the Mira distance scale to Galactic globular clusters and to other galaxies.
HFIR Vessel Maximum Permissible Pressures for Operating Period 26 to 50 EFPY (100 MW)
Cheverton, R.D.; Inger, J.R.
1999-01-01T23:59:59.000Z
Extending the life of the HFIR pressure vessel from 26 to 50 EFPY (100 MW) requires an updated calculation of the maximum permissible pressure for a range in vessel operating temperatures (40-120 F). The maximum permissible pressure is calculated using the equal-potential method, which takes advantage of knowledge gained from periodic hydrostatic proof tests and uses the test conditions (pressure, temperature, and frequency) as input. The maximum permissible pressure decreases with increasing time between hydro tests but is increased each time a test is conducted. The minimum values that occur just prior to a test either increase or decrease with time, depending on the vessel temperature. The minimum value of these minimums is presently specified as the maximum permissible pressure. For three vessel temperatures of particular interest (80, 88, and 110 F) and a nominal time of 3.0 EFPY(100 MVV)between hydro tests, these pressures are 677, 753, and 850 psi. For the lowest temperature of interest (40 F), the maximum permissible pressure is 295 psi.
On the maximum value of the cosmic abundance of oxygen and the oxygen yield
L. S. Pilyugin; T. X. Thuan; J. M. Vilchez
2007-01-11T23:59:59.000Z
We search for the maximum oxygen abundance in spiral galaxies. Because this maximum value is expected to occur in the centers of the most luminous galaxies, we have constructed the luminosity - central metallicity diagram for spiral galaxies, based on a large compilation of existing data on oxygen abundances of HII regions in spiral galaxies. We found that this diagram shows a plateau at high luminosities (-22.3 oxygen abundance 12+log(O/H) ~ 8.87. This provides strong evidence that the oxygen abundance in the centers of the most luminous metal-rich galaxies reaches the maximum attainable value of oxygen abundance. Since some fraction of the oxygen (about 0.08 dex) is expected to be locked into dust grains, the maximum value of the true gas+dust oxygen abundance in spiral galaxies is 12+log(O/H) ~ 8.95. This value is a factor of ~ 2 higher than the recently estimated solar value. Based on the derived maximum oxygen abundance in galaxies, we found the oxygen yield to be about 0.0035, depending on the fraction of oxygen incorporated into dust grains.
A RECONNECTION-DRIVEN RAREFACTION WAVE MODEL FOR CORONAL OUTFLOWS
Bradshaw, S. J. [Department of Physics and Astronomy, Rice University, Houston, TX 77005 (United States); Aulanier, G. [LESIA, Observatoire de Paris, CNRS, UPMC, Universite Paris Diderot, 5 place Jules Janssen, 92190 Meudon (France); Del Zanna, G., E-mail: stephen.bradshaw@rice.edu [DAMTP, Centre for Mathematical Sciences, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)
2011-12-10T23:59:59.000Z
We conduct numerical experiments to determine whether interchange reconnection at high altitude coronal null points can explain the outflows observed as blueshifts in coronal emission lines at the boundaries between open and closed magnetic field regions. In this scenario, a strong, post-reconnection pressure gradient forms in the field-aligned direction when dense and hot, active region core loops reconnect with neighboring tenuous and cool, open field lines. We find that the pressure gradient drives a supersonic outflow and a rarefaction wave develops in both the open and closed post-reconnection magnetic field regions. We forward-model the spectral line profiles for a selection of coronal emission lines to predict the spectral signatures of the rarefaction wave. We find that the properties of the rarefaction wave are consistent with the observed velocity versus temperature structure of the corona in the outflow regions, where the velocity increases with the formation temperature of the emission lines. In particular, we find excellent agreement between the predicted and observed Fe XII 195.119 A spectral line profiles in terms of the blueshift (10 km s{sup -1}), full width at half-maximum (83 mA) and symmetry. Finally, we find that T{sub i} < T{sub e} in the open field region, which indicates that the interchange reconnection scenario may provide a viable mechanism and source region for the slow solar wind.
Brian J. Smith; M. G. Raymer
2007-02-21T23:59:59.000Z
The position-representation wave function for multi-photon states and its equation of motion are introduced. A major strength of the theory is that it describes the complete evolution (including polarization and entanglement) of multi-photon states propagating through inhomogeneous media. As a demonstration of the two-photon wave function's use, we show how two photons in an orbital-angular-momentum entangled state decohere upon propagation through a turbulent atmosphere.
Rhinefrank, Kenneth E. [Columbia Power Technologies, Inc.; Lenee-Bluhm, Pukha [Columbia Power Technologies, Inc.; Prudell, Joseph H. [Columbia Power Technologies, Inc.; Schacher, Alphonse A. [Columbia Power Technologies, Inc.; Hammagren, Erik J. [Columbia Power Technologies, Inc.; Zhang, Zhe [Columbia Power Technologies, Inc.
2013-07-29T23:59:59.000Z
The most prudent path to a full-scale design, build and deployment of a wave energy conversion (WEC) system involves establishment of validated numerical models using physical experiments in a methodical scaling program. This Project provides essential additional rounds of wave tank testing at 1:33 scale and ocean/bay testing at a 1:7 scale, necessary to validate numerical modeling that is essential to a utility-scale WEC design and associated certification.
Wave function as geometric entity
B. I. Lev
2011-02-10T23:59:59.000Z
A new approach to the geometrization of the electron theory is proposed. The particle wave function is represented by a geometric entity, i.e., Clifford number, with the translation rules possessing the structure of Dirac equation for any manifold. A solution of this equation is obtained in terms of geometric treatment. Interference of electrons whose wave functions are represented by geometric entities is considered. New experiments concerning the geometric nature of electrons are proposed.
Steady water waves with multiple critical layers
Mats Ehrnström; Joachim Escher; Erik Wahlén
2011-04-01T23:59:59.000Z
We construct small-amplitude periodic water waves with multiple critical layers. In addition to waves with arbitrarily many critical layers and a single crest in each period, two-dimensional sets of waves with several crests and troughs in each period are found. The setting is that of steady two-dimensional finite-depth gravity water waves with vorticity.
Spectral Modeling of SNe Ia Near Maximum Light: Probing the Characteristics of Hydro Models
E. Baron; S. Bongard; David Branch; Peter H. Hauschildt
2006-03-03T23:59:59.000Z
We have performed detailed NLTE spectral synthesis modeling of 2 types of 1-D hydro models: the very highly parameterized deflagration model W7, and two delayed detonation models. We find that overall both models do about equally well at fitting well observed SNe Ia near to maximum light. However, the Si II 6150 feature of W7 is systematically too fast, whereas for the delayed detonation models it is also somewhat too fast, but significantly better than that of W7. We find that a parameterized mixed model does the best job of reproducing the Si II 6150 line near maximum light and we study the differences in the models that lead to better fits to normal SNe Ia. We discuss what is required of a hydro model to fit the spectra of observed SNe Ia near maximum light.
Fast singular value decomposition combined maximum entropy method for plasma tomography
Kim, Junghee; Choe, W. [Department of Physics, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701(Korea, Republic of)
2006-02-15T23:59:59.000Z
The maximum entropy method (MEM) is a widely used reconstruction algorithm in plasma physics. Drawbacks of the conventional MEM are its heavy time-consuming process and possible generation of noisy reconstruction results. In this article, a modified maximum entropy algorithm is described which speeds up the calculation and shows better noise handling capability. Similar to the rapid minimum Fisher information method, the modified maximum entropy algorithm uses simple matrix operations instead of treating a fully nonlinear problem. The preprocess for rapid tomographic calculation is based on the vector operations and the singular value decomposition (SVD). The initial guess of the sought-for emissivity is calculated by SVD and this helped reconstruction about ten times faster than the conventional MEM. Therefore, the developed fast MEM can be used for intershot tomographic analyses of fusion plasmas.
The Role of Gravity Waves in the Formation and Organization of Clouds during TWPICE
Reeder, Michael J. [Monash University; Lane, Todd P. [University of Melbourne; Hankinson, Mai Chi Nguyen [Monash University
2013-09-27T23:59:59.000Z
All convective clouds emit gravity waves. While it is certain that convectively-generated waves play important parts in determining the climate, their precise roles remain uncertain and their effects are not (generally) represented in climate models. The work described here focuses mostly on observations and modeling of convectively-generated gravity waves, using the intensive observations from the DoE-sponsored Tropical Warm Pool International Cloud Experiment (TWP-ICE), which took place in Darwin, from 17 January to 13 February 2006. Among other things, the research has implications the part played by convectively-generated gravity waves in the formation of cirrus, in the initiation and organization of further convection, and in the subgrid-scale momentum transport and associated large-scale stresses imposed on the troposphere and stratosphere. The analysis shows two groups of inertia-gravity waves are detected: group L in the middle stratosphere during the suppressed monsoon period, and group S in the lower stratosphere during the monsoon break period. Waves belonging to group L propagate to the south-east with a mean intrinsic period of 35 h, and have vertical and horizontal wavelengths of about 5-6 km and 3000-6000 km, respectively. Ray tracing calculations indicate that these waves originate from a deep convective region near Indonesia. Waves belonging to group S propagate to the south-south-east with an intrinsic period, vertical wavelength and horizontal wavelength of about 45 h, 2 km and 2000-4000 km, respectively. These waves are shown to be associated with shallow convection in the oceanic area within about 1000 km of Darwin. The intrinsic periods of high-frequency waves are estimated to be between 20-40 minutes. The high-frequency wave activity in the stratosphere, defined by mass-weighted variance of the vertical motion of the sonde, has a maximum following the afternoon local convection indicating that these waves are generated by local convection. The wave activity is strongest in the lower stratosphere below 22 km and, during the suppressed monsoon period, is modulated with a 3-4-day period. The concentration of the wave activity in the lower stratosphere is consistent with the properties of the environment in which these waves propagate, whereas its 3-4-day modulation is explained by the variation of the convection activity in the TWP-ICE domain. At low rainfall intensity the wave activity increases as rainfall intensity increases. At high values of rainfall intensity, however, the wave activity associated with deep convective clouds is independent of the rainfall intensity. The convection and gravity waves observed during TWP-ICE are simulated with the Weather Research and Forecasting (WRF) Model. These simulations are compared with radiosonde observations described above and are used to determine some of the properties of convectively generated gravity waves. The gravity waves appear to be well simulated by the model. The model is used to explore the relationships between the convection, the gravity waves and cirrus.
Byrne, Raymond Harry; Silva Monroy, Cesar Augusto.
2012-12-01T23:59:59.000Z
The valuation of an electricity storage device is based on the expected future cash ow generated by the device. Two potential sources of income for an electricity storage system are energy arbitrage and participation in the frequency regulation market. Energy arbitrage refers to purchasing (stor- ing) energy when electricity prices are low, and selling (discharging) energy when electricity prices are high. Frequency regulation is an ancillary service geared towards maintaining system frequency, and is typically procured by the independent system operator in some type of market. This paper outlines the calculations required to estimate the maximum potential revenue from participating in these two activities. First, a mathematical model is presented for the state of charge as a function of the storage device parameters and the quantities of electricity purchased/sold as well as the quantities o ered into the regulation market. Using this mathematical model, we present a linear programming optimization approach to calculating the maximum potential revenue from an elec- tricity storage device. The calculation of the maximum potential revenue is critical in developing an upper bound on the value of storage, as a benchmark for evaluating potential trading strate- gies, and a tool for capital nance risk assessment. Then, we use historical California Independent System Operator (CAISO) data from 2010-2011 to evaluate the maximum potential revenue from the Tehachapi wind energy storage project, an American Recovery and Reinvestment Act of 2009 (ARRA) energy storage demonstration project. We investigate the maximum potential revenue from two di erent scenarios: arbitrage only and arbitrage combined with the regulation market. Our analysis shows that participation in the regulation market produces four times the revenue compared to arbitrage in the CAISO market using 2010 and 2011 data. Then we evaluate several trading strategies to illustrate how they compare to the maximum potential revenue benchmark. We conclude with a sensitivity analysis with respect to key parameters.
Physica D 159 (2001) 3557 Wave group dynamics in weakly nonlinear long-wave models
Pelinovsky, Dmitry
Physica D 159 (2001) 35Â57 Wave group dynamics in weakly nonlinear long-wave models Roger Grimshawa Communicated by A.C. Newell Abstract The dynamics of wave groups is studied for long waves, using the framework reserved. Keywords: Wave group dynamics; KortewegÂde Vries equation; Nonlinear SchrÂ¨odinger equation 1
Nazarenko, Sergey
Gravity Wave Turbulence in Wave Tanks: Space and Time Statistics Sergei Lukaschuk,1,* Sergey the first simultaneous space-time measurements for gravity wave turbulence in a large laboratory flume. We found that the slopes of k and ! wave spectra depend on wave intensity. This cannot be explained by any
What is the maximum rate at which entropy of a string can increase?
Ropotenko, Kostyantyn [State Administration of Communications, Ministry of Transport and Communications of Ukraine 22, Khreschatyk, 01001, Kyiv (Ukraine)
2009-03-15T23:59:59.000Z
According to Susskind, a string falling toward a black hole spreads exponentially over the stretched horizon due to repulsive interactions of the string bits. In this paper such a string is modeled as a self-avoiding walk and the string entropy is found. It is shown that the rate at which information/entropy contained in the string spreads is the maximum rate allowed by quantum theory. The maximum rate at which the black hole entropy can increase when a string falls into a black hole is also discussed.
Hydrodynamic Relaxation of an Electron Plasma to a Near-Maximum Entropy State
Rodgers, D. J.; Servidio, S.; Matthaeus, W. H.; Mitchell, T. B.; Aziz, T. [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Montgomery, D. C. [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)
2009-06-19T23:59:59.000Z
Dynamical relaxation of a pure electron plasma in a Malmberg-Penning trap is studied, comparing experiments, numerical simulations and statistical theories of weakly dissipative two-dimensional (2D) turbulence. Simulations confirm that the dynamics are approximated well by a 2D hydrodynamic model. Statistical analysis favors a theoretical picture of relaxation to a near-maximum entropy state with constrained energy, circulation, and angular momentum. This provides evidence that 2D electron fluid relaxation in a turbulent regime is governed by principles of maximum entropy.
Maximum-Entropy Closures for Kinetic Theories of Neuronal Network Dynamics
Rangan, Aaditya V.; Cai, David [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)
2006-05-05T23:59:59.000Z
We analyze (1+1)D kinetic equations for neuronal network dynamics, which are derived via an intuitive closure from a Boltzmann-like equation governing the evolution of a one-particle (i.e., one-neuron) probability density function. We demonstrate that this intuitive closure is a generalization of moment closures based on the maximum-entropy principle. By invoking maximum-entropy closures, we show how to systematically extend this kinetic theory to obtain higher-order (1+1)D kinetic equations and to include coupled networks of both excitatory and inhibitory neurons.
Maximum Entropy Models of Shortest Path and Outbreak Distributions in Networks
Bauckhage, Christian; Hadiji, Fabian
2015-01-01T23:59:59.000Z
Properties of networks are often characterized in terms of features such as node degree distributions, average path lengths, diameters, or clustering coefficients. Here, we study shortest path length distributions. On the one hand, average as well as maximum distances can be determined therefrom; on the other hand, they are closely related to the dynamics of network spreading processes. Because of the combinatorial nature of networks, we apply maximum entropy arguments to derive a general, physically plausible model. In particular, we establish the generalized Gamma distribution as a continuous characterization of shortest path length histograms of networks or arbitrary topology. Experimental evaluations corroborate our theoretical results.
Gravitational wave recoils in non-axisymmetric Robinson-Trautman spacetimes
R. F. Aranha; I. Damião Soares; E. V. Tonini
2014-07-16T23:59:59.000Z
We examine the gravitational wave recoil waves and the associated net kick velocities in non-axisymmetric Robinson-Trautman spacetimes. We use characteristic initial data for the dynamics corresponding to non-head-on collisions of black holes. We make a parameter study of the kick distributions, corresponding to an extended range of the incidence angle $\\rho_0$ in the initial data. For the range of $\\rho_0$ examined ($3^{\\circ} \\leq \\rho_0 \\leq 110^{\\circ}$) the kick distributions as a function of the symmetric mass parameter $\\eta$ satisfy a law obtained from an empirical modification of the Fitchett law, with a parameter $C$ that accounts for the non-zero net gravitational momentum wave fluxes for the equal mass case. The law fits accurately the kick distributions for the range of $\\rho_0$ examined, with a rms normalized error of the order of $5 \\%$. For the equal mass case the nonzero net gravitational wave momentum flux increases as $\\rho_0$ increases, up to $\\rho_0 \\simeq 55^{\\circ}$ beyond which it decreases. The maximum net kick velocity is about $190 {\\rm km/s}$ for for the boost parameter considered. For $\\rho_0 \\geq 50^{\\circ}$ the distribution is a monotonous function of $\\eta$. The angular patterns of the gravitational waves emitted are examined. Our analysis includes the two polarization modes present in wave zone curvature.
Propagation Plane waves -High order Modes
Berlin,Technische UniversitÃ¤t
1 Propagation Â· Plane waves - High order Modes y x a One wave: p(x,y,t)=p0 cos(k y)e-jk x e j t vy(y,t)= 0 ; y=0,a xy } ky = n a Propagation Â· Plane waves - High order Modes x n a p(x,y,t)=pn cos( y + - +- + + - +- + - + + +- - - (m,n) #12;4 Propagation Â· Circular duct Â Helical waves (spiralling waves) kc=m/a kz k
Propagation Plane waves -High order Modes
Berlin,Technische UniversitÃ¤t
1 Propagation Â· Plane waves - High order Modes y x a ky = n a One wave: p(x,y,t)=p0 cos(k y)e-jk x e j t vy(y,t)= 0 ; y=0,a xy } Propagation Â· Plane waves - High order Modes x n a p(x,y,t)=pn cos( y;4 Propagation Â· Circular duct Â Helical waves (spiralling waves) kc=m/a kz kH Projection: Propagation #12
Phase-coherent mapping of gravitational-wave backgrounds using ground-based laser interferometers
Joseph D. Romano; Stephen R. Taylor; Neil J. Cornish; Jonathan Gair; Chiara M. F. Mingarelli; Rutger van Haasteren
2015-05-27T23:59:59.000Z
We extend the formalisms developed in Gair et al. and Cornish and van Haasteren to create maps of gravitational-wave backgrounds using a network of ground-based laser interferometers. We show that in contrast to pulsar timing arrays, which are insensitive to half of the gravitational-wave sky (the curl modes), a network of ground-based interferometers is sensitive to both the gradient and curl components of the background. The spatial separation of a network of interferometers, or of a single interferometer at different times during its rotational and orbital motion around the Sun, allows for recovery of both components. We derive expressions for the response functions of a laser interferometer in the small-antenna limit, and use these expressions to calculate the overlap reduction function for a pair of interferometers. We also construct maximum-likelihood estimates of the + and x-polarization modes of the gravitational-wave sky in terms of the response matrix for a network of ground-based interferometers, evaluated at discrete times during Earth's rotational and orbital motion around the Sun. We demonstrate the feasibility of this approach for some simple simulated backgrounds (a single point source and spatially-extended distributions having only grad or curl components), calculating maximum-likelihood sky maps and uncertainty maps based on the (pseudo)inverse of the response matrix. The distinction between this approach and standard methods for mapping gravitational-wave power is also discussed.
Timofeev, I V
2012-01-01T23:59:59.000Z
The impact of superthermal electrons on dispersion properties of isotropic plasmas and on the modulational instability of a monochromatic Langmuir wave is studied for the case when the power-law tail of the electron distribution function extends to relativistic velocities and contains most of the plasma kinetic energy. Such an energetic tail of electrons is shown to increase the thermal correction to the Langmuir wave frequency, which is equivalent to the increase of the effective electron temperature in the fluid approach, and has almost no impact on the dispersion of ion-acoustic waves, in which the role of temperature is played by the thermal spread of low-energy core electrons. It is also found that the spectrum of modulational instability in the non-maxwellian plasma narrows significantly, as compared to the equilibrium case, without change of the maximum growth rate and the corresponding wavenumber.
Resonant behaviour of an oscillating wave energy converter in a channel
E. Renzi; F. Dias
2012-04-10T23:59:59.000Z
A mathematical model is developed to study the behaviour of an oscillating wave energy converter in a channel. During recent laboratory tests in a wave tank, peaks in the hydrodynamic actions on the converter occurred at certain frequencies of the incident waves. This resonant mechanism is known to be generated by the transverse sloshing modes of the channel. Here the influence of the channel sloshing modes on the performance of the device is further investigated. Within the framework of a linear inviscid potential-flow theory, application of the Green theorem yields a hypersingular integral equation for the velocity potential in the fluid domain. The solution is found in terms of a fast-converging series of Chebyshev polynomials of the second kind. The physical behaviour of the system is then analysed, showing sensitivity of the resonant sloshing modes to the geometry of the device, that concurs in increasing the maximum efficiency. Analytical results are validated with available numerical and experimental data.
Resonant behaviour of an oscillating wave energy converter in a channel
Renzi, E
2012-01-01T23:59:59.000Z
A mathematical model is developed to study the behaviour of an oscillating wave energy converter in a channel. During recent laboratory tests in a wave tank, peaks in the hydrodynamic actions on the converter occurred at certain frequencies of the incident waves. This resonant mechanism is known to be generated by the transverse sloshing modes of the channel. Here the influence of the channel sloshing modes on the performance of the device is further investigated. Within the framework of a linear inviscid potential-flow theory, application of the Green theorem yields a hypersingular integral equation for the velocity potential in the fluid domain. The solution is found in terms of a fast-converging series of Chebyshev polynomials of the second kind. The physical behaviour of the system is then analysed, showing sensitivity of the resonant sloshing modes to the geometry of the device, that concurs in increasing the maximum efficiency. Analytical results are validated with available numerical and experimental d...
Wave blocking and partial transmission in subcritical flows over an obstacle
Léo-Paul Euvé; Florent Michel; Renaud Parentani; Germain Rousseaux
2015-02-06T23:59:59.000Z
We study and measure the transmission coefficient of counter-propagating shallow-water waves produced by a wave generator and scattered by an obstacle. To precisely compare theoretical predictions and experimental data, we consider $\\sim 25$ frequencies for 5 subcritical background flows, where the maximum value of the Froude number ranges from $0.5$ to $0.75$. For each flow, the transmission coefficient displays a sharp transition separating total transmission from wave-blocking. Both the width and the central frequency of the transition are in good agreement with their theoretical values. The shape of the obstacle is identical to that used by the Vancouver team in the recent experiment aiming at detecting the analogue of stimulated Hawking radiation. Our results are compatible with the observations that have been reported. They complete them by establishing that the contribution of the transmission coefficient cannot be neglected for the lower half of the probed frequency range.
Wave-Turbulence Interactions in a Breaking Mountain Wave Craig Epifanio and Tingting Qian
#12;Dissipation of Mean Wave Energy · Mean wave energy E is just the total energy (kinetic + available · The dissipation of mean wave energy is caused by the turbulent momentum fluxes--specifically, by their tendency
Energy-momentum relation for solitary waves of relativistic wave equations
T. V. Dudnikova; A. I. Komech; H. Spohn
2005-08-23T23:59:59.000Z
Solitary waves of relativistic invariant nonlinear wave equation with symmetry group U(1) are considered. We prove that the energy-momentum relation for spherically symmetric solitary waves coincides with the Einstein energy-momentum relation for point particles.
Longridge, Jonathon Kent
1993-01-01T23:59:59.000Z
Waves in the oceans pose challenging problems to offshore structural design because they arc irregular and can be highly nonlinear. Although these irregular waves can be viewed as the summation of many linear wave components of different...
NOAA Technical Memorandum NWS HYDRO 39 PROBABLE MAXIMUM PRECIPITATION FOR THE UPPER
NOAA Technical Memorandum NWS HYDRO 39 PROBABLE MAXIMUM PRECIPITATION FOR THE UPPER DEERFIELD RIVER The Office of Hydrology (HYDRO) of the National Weather Service (NWS) develops procedures for making river agencies, and conducts pertinent research and development. NOAA Technical Memorandums in the NWS HYDRO
Analysis and Optimization of Maximum Power Point Tracking Algorithms in the Presence of
Odam, Kofi
, Charles R. Sullivan, Senior Member, IEEE Abstract--This paper analyzes the effect of noise on sev- eral maximum power point tracking (MPPT) algorithms for photovoltaic systems. Noise is an essential of the signals, mitigating the noise. The effect of noise and other parameters on tracking performance
Maximum Output Amplitude of Linear Systems for certain Input Constraints1
Sontag, Eduardo
of this input and calculates the maximum amplitude of the output. The solution of this problem is a necessary, Linear Sys- tems. 1 Introduction and Motivation Most practical control problems are dominated by hard bounds. Valves can only be operated between fully open and fully closed, pumps and compressors have
Blind Equalization via Approximate Maximum Likelihood Source Seungjin CHOI x1 and Andrzej CICHOCKI y
Choi, Seungjin
Blind Equalization via Approximate Maximum Likelihood Source Separation Seungjin CHOI x1, RIKEN 2-1 Hirosawa, Wako-shi Saitama 351-0198, JAPAN Abstract Blind equalization of single input multiple output (SIMO) FIR channels can be refor- mulated as the problem of blind source separation
Harrington, Jerry Y.
Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part I: Maximum Solar Heating CHRISTOPHER M. HARTMAN AND JERRY Y. HARRINGTON Department of Meteorology, The Pennsylvania November 2004) ABSTRACT The effects of solar heating and infrared cooling on the vapor depositional growth
Maximum principle and bang-bang property of time optimal controls for Schrodinger type systems
Paris-Sud XI, Université de
Maximum principle and bang-bang property of time optimal controls for Schr¨odinger type systems J conditions for the bang- bang property of optimal controls. The results are then applied to some systems-Bang property, Schr¨odinger equation 1 Introduction Time optimal control is a classical problem for linear
Paris-Sud XI, Université de
Recursive maximum likelihood estimation for structural health monitoring: Kalman and particle by a likelihood approach. In a first part the structural health monitoring problem is written in term of recursive al [6] in a more simple framework. Particle approximation for health monitoring was already proposed
Maximum-Power-Point Tracking Method of Photovoltaic Power System Using Single Transducer
Fujimoto, Hiroshi
Maximum-Power-Point Tracking Method of Photovoltaic Power System Using Single Transducer Toshihiko) method of a photovoltaic power system with less transducer count. A unique feature of this method concern on an environmental issue since 1990's. Above all, a photovoltaic power generation system is one
Design of wind farm layout for maximum wind energy capture Andrew Kusiak*, Zhe Song
Kusiak, Andrew
Design of wind farm layout for maximum wind energy capture Andrew Kusiak*, Zhe Song Intelligent Accepted 24 August 2009 Available online 22 September 2009 Keywords: Wind farm Wind turbine Layout design Optimization Evolutionary algorithms Operations research a b s t r a c t Wind is one of the most promising
Electrical Estimation of Conditional Probability for Maximum-likelihood Based PMD Mitigation
Zweck, John
Xi, T¨ulay Adali, and John Zweck Department of Computer Science and Electrical Engineering UniversityElectrical Estimation of Conditional Probability for Maximum-likelihood Based PMD Mitigation Wenze probability density functions in the presence of both all-order PMD and ASE noise are estimated electronically
Brayton Cycles: From the ...rst law, the maximum transfers for component SSSF control volumes are
. For the simple reversible Brayton cycle of given pressure ratio rp $ (p2=p1) = (p3=p4) [compare Example 9.4, pp is higher than 1 r (2=7) . For the ideal regenerator, the thermal e¢ ciency approaches the Carnot-cycle eBrayton Cycles: From the ...rst law, the maximum transfers for component SSSF control volumes are w
Maximum Likelihood Estimation of Mixture Densities for Binned and Truncated Multivariate
Smyth, Padhraic
Maximum Likelihood Estimation of Mixture Densities for Binned and Truncated Multivariate Data in data analysis and machine learning. This paper addresses the problem of fitting mixture densities to multivariate binned and truncated data. The EM approach proposed by McLachlan and Jones (1988
EXTENSION OF THE MAXIMUM POWER REGION OF DOUBLY-SALIENT VARIABLE RELUCTANCE MOTORS
Paris-Sud XI, UniversitÃ© de
-Salient Variable Reluctance Motors (DSVRM) has been investigated and developed for variable-speed drives during, variable-frequency generators, wind wheels, machine tools, etc.). In these applications, it is generally necessary to operate in a regime of a high speed ux-weakening (zone of maximum constant power), for a better
Turro, Nicholas J.
Hydrogen Molecules inside Fullerene C70: Quantum Dynamics, Energetics, Maximum Occupancy of Chemistry, New York UniVersity, New York, New York 10003, Department of Chemistry, Brown UniVersity, ProVidence, Rhode Island 02912, and Department of Chemistry, Columbia UniVersity, New York, New York 10027 Received
Vision Research 40 (2000) 11571165 Local luminance factors that determine the maximum disparity for
Kingdom, Frederick A. A.
2000-01-01T23:59:59.000Z
Vision Research 40 (2000) 11571165 Local luminance factors that determine the maximum disparity dense arrays of micropatterns, whose luminance characteristics were manipulated. In Experiment 1, we with luminance spatial frequency and with Gabor size, but was constant for a constant bandwidth (frequency times
Exact Maximum Likelihood estimator for the BL-GARCH model under elliptical distributed
Paris-Sud XI, Université de
Exact Maximum Likelihood estimator for the BL-GARCH model under elliptical distributed innovations, Brisbane QLD 4001, Australia Abstract We are interested in the parametric class of Bilinear GARCH (BL-GARCH examine, in this paper, the BL-GARCH model in a general setting under some non-normal distributions. We
Learning with MaximumEntropy Distributions \\Lambda Yishay Mansour Mariano Schain
Mansour, Yishay
Learning with MaximumEntropy Distributions \\Lambda Yishay Mansour Mariano Schain Computer Science Dept. TelAviv University fmansour,marianog@math.tau.ac.il Abstract We are interested in distributions which are de rived as a maximumentropy distribution given a set of constraints. More specifically, we
A Global Maximum Power Point Tracking Method for PV Module Integrated Converters
Liberzon, Daniel
with large arrays of series-connected PV mod- ules connected to a central inverter. Figure 1(a) depicts, it is conceivable that these systems do not extract the maximum possible power from the PV array when individual PV to partial shading. In such systems, power electronics circuits are integrated directly with PV modules
Demirel, Melik C.
Degradation Overview Westinghouse applies a conservative approach when evaluating degradation on a gasket evaluation. The team was tasked with collecting this data to determine when degradation endangers the pressure seal. Objectives The team's objectives were to determine the maximum degradation which the gasket
Stone, G. A.; DeVito, E. M.; Nease, N. H.
2002-01-01T23:59:59.000Z
Texas adopted in its residential building energy code a maximum 0.40 solar heat gain coefficient (SHGC) for fenestration (e.g., windows, glazed doors and skylights)-a critical driver of cooling energy use, comfort and peak demand. An analysis...
Jagannatham, Aditya K.
in wireless sensor networks (WSN). The proposed algo- rithm employs the temporal correlation of the narrowband Wireless Sensor Network (WSN), Likelihood, Sphere De- coder 1. INTRODUCTION Wireless Sensor Networks (WSNBayesian Data and Channel Joint Maximum-Likelihood Based Error Correction in Wireless Sensor
Maximum-Lifetime Multi-Channel Routing in Wireless Sensor Networks
Nasipuri, Asis
Maximum-Lifetime Multi-Channel Routing in Wireless Sensor Networks Amitangshu Pal and Asis Nasipuri and routing problem in multi-channel wireless sensor networks for maximizing the worst case network lifetime solution for the problem. Keywords: Wireless sensor networks, multi-channel rout- ing, distributed
The chronology of the Last Glacial Maximum and deglacial events in central Argentine Patagonia
The chronology of the Last Glacial Maximum and deglacial events in central Argentine Patagonia and deglaciation in the Lago PueyrredoÂ´n valley of central Patagonia, 47.5 S, Argentina. The valley was a major and the onset of deglaciation occurred broadly synchronously throughout Patagonia. Deglaciation resulted
Paris-Sud XI, UniversitÃ© de
periods often appear in industry due to a machine breakdown (stochastic) or preventive maintenance of machine unavailability. However, in some cases (e.g. preventive maintenance), the maintenance of a machineSingle-machine scheduling with periodic and exible periodic maintenance to minimize maximum
THE SECOND LAW OF THERMODYNAMICS AND THE GLOBAL CLIMATE SYSTEM: A REVIEW OF THE MAXIMUM
Lorenz, Ralph D.
to absorption of solar radiation in the climate system is found to be irrelevant to the maximized prop- erties from hot to cold places, thereby producing the kinetic energy of the fluid itself. His generalTHE SECOND LAW OF THERMODYNAMICS AND THE GLOBAL CLIMATE SYSTEM: A REVIEW OF THE MAXIMUM ENTROPY
Hydraulic limits on maximum plant transpiration and the emergence of the safetyefficiency trade-off
Jackson, Robert B.
Hydraulic limits on maximum plant transpiration and the emergence of the safetyefficiency trade.12126 Key words: hydraulic limitation, safety efficiency trade-off, soilplantatmosphere model, trait hydraulics constrain ecosystem productivity by setting physical limits to water transport and hence carbon
Performance of Photovoltaic Maximum Power Point Tracking Algorithms in the Presence of Noise
Odam, Kofi
Performance of Photovoltaic Maximum Power Point Tracking Algorithms in the Presence of Noise tracking (MPPT) algorithms for photovoltaic systems, including how noise affects both tracking speed-performance photovoltaic sys- tems. An intelligent controller adjusts the voltage, current, or impedance seen by a solar
PHYSICAL REVIEW E 86, 041144 (2012) Efficiency at maximum power for classical particle transport
Lindenberg, Katja
2012-01-01T23:59:59.000Z
PHYSICAL REVIEW E 86, 041144 (2012) Efficiency at maximum power for classical particle transport transport. DOI: 10.1103/PhysRevE.86.041144 PACS number(s): 05.70.Ln, 05.40.-a, 05.20.-y I. INTRODUCTION Over, operating between a hot and cold bath at temperatures T (1) and T (2) , respectively, possesses universal
Optimization of stomatal conductance for maximum carbon gain under dynamic soil moisture
Katul, Gabriel
Optimization of stomatal conductance for maximum carbon gain under dynamic soil moisture Stefano Accepted 26 September 2013 Available online 9 October 2013 Keywords: Optimization Photosynthesis Soil moisture Stomatal conductance Transpiration a b s t r a c t Optimization theories explain a variety
A Distributed Approach to Maximum Power Point Tracking for Photovoltaic Sub-Module Differential
Liberzon, Daniel
of the proposed distributed algorithm. I. INTRODUCTION IN photovoltaic (PV) energy systems, PV modules are often of the system, small size and low power ratings of the power electronics circuit components. Due1 A Distributed Approach to Maximum Power Point Tracking for Photovoltaic Sub-Module Differential
An Analysis of the Maximum Drawdown Risk Malik Magdon-Ismail
Magdon-Ismail, Malik
Engineering Cairo University Giza, Egypt. amir@alumni.caltech.edu Introduction. The maximum cumulative loss to the Calmar ratio is the Sterling ratio, Sterling(T) = Return over [0,T ] MDD over [0,T ]-10% , and our discussion applies equally well to the Sterling ratio. 1 #12;primarily due to a lack of an analytical
An Analysis of the Maximum Drawdown Risk Malik MagdonIsmail
Magdon-Ismail, Malik
Engineering Cairo University Giza, Egypt. amir@alumni.caltech.edu Introduction. The maximum cumulative loss is not prevalent 1 Similar to the Calmar ratio is the Sterling ratio, Sterling(T ) = Return over [0,T ] MDD over [0,T ]-10% , and our discussion applies equally well to the Sterling ratio. 1 #12; primarily due
Extraction of Spectral Functions from Dyson-Schwinger Studies via the Maximum Entropy Method
Dominik Nickel
2006-07-20T23:59:59.000Z
It is shown how to apply the Maximum Entropy Method (MEM) to numerical Dyson-Schwinger studies for the extraction of spectral functions of correlators from their corresponding Euclidean propagators. Differences to the application in lattice QCD are emphasized and, as an example, the spectral functions of massless quarks in cold and dense matter are presented.
Nasser, Hassan
2014-01-01T23:59:59.000Z
We propose a numerical method to learn Maximum Entropy (MaxEnt) distributions with spatio-temporal constraints from experimental spike trains. This is an extension of two papers [10] and [4] who proposed the estimation of parameters where only spatial constraints were taken into account. The extension we propose allows to properly handle memory effects in spike statistics, for large sized neural networks.
Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensembles out of equilibrium Gavin E at equilibrium? Here, we argue the most appropriate additional parameter is the nonequilibrium entropy of ways that the same system can be out of equilibrium. That the equilibrium entropy is maximized given
Extraction of spectral functions from Dyson-Schwinger studies via the maximum entropy method
Nickel, Dominik [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany)]. E-mail: dominik.nickel@physik.tu-darmstadt.de
2007-08-15T23:59:59.000Z
It is shown how to apply the Maximum Entropy Method (MEM) to numerical Dyson-Schwinger studies for the extraction of spectral functions of correlators from their corresponding Euclidean propagators. Differences to the application in lattice QCD are emphasized and, as an example, the spectral functions of massless quarks in cold and dense matter are presented.
Lattice Field Theory with the Sign Problem and the Maximum Entropy Method
Masahiro Imachi; Yasuhiko Shinno; Hiroshi Yoneyama
2007-02-09T23:59:59.000Z
Although numerical simulation in lattice field theory is one of the most effective tools to study non-perturbative properties of field theories, it faces serious obstacles coming from the sign problem in some theories such as finite density QCD and lattice field theory with the $\\theta$ term. We reconsider this problem from the point of view of the maximum entropy method.
Relating maximum airway dilation and subsequent reconstriction to reactivity in human lungs
Lutchen, Kenneth
Relating maximum airway dilation and subsequent reconstriction to reactivity in human lungs Lauren in human lungs. J Appl Physiol 96: 18081814, 2004. First published February 6, 2004; 10.1152/japplphysiol reactivity in healthy lungs by prohibiting DI for an extended period. The present study had two goals. First
Modulation and kinematics of mechanically-generated short gravity waves riding on long waves
Spell, Charles Anthony
1992-01-01T23:59:59.000Z
for the degree of MASTER OF SCIENCE December 1992 Major Subject: Ocean Engineering MODULATION AND KINEMATICS OF MECHANICALLY- GENERATED SHORT GRAVITY WAVES RIDING ON LONG WAVES A Thesis by C~S ANTHONY SPELL Approved as to style and content by: Jun Zhang... fundamental nonlinear wave interaction occurring in an irregular wave field. The objectives of the present study are now stated: ~ Generate a dual-component wave formed from the interaction of two inde- pendently propagating monochromatic wave trains in a...
Surface wave chemical detector using optical radiation
Thundat, Thomas G.; Warmack, Robert J.
2007-07-17T23:59:59.000Z
A surface wave chemical detector comprising at least one surface wave substrate, each of said substrates having a surface wave and at least one measurable surface wave parameter; means for exposing said surface wave substrate to an unknown sample of at least one chemical to be analyzed, said substrate adsorbing said at least one chemical to be sensed if present in said sample; a source of radiation for radiating said surface wave substrate with different wavelengths of said radiation, said surface wave parameter being changed by said adsorbing; and means for recording signals representative of said surface wave parameter of each of said surface wave substrates responsive to said radiation of said different wavelengths, measurable changes of said parameter due to adsorbing said chemical defining a unique signature of a detected chemical.
Two-wave interaction in ideal magnetohydrodynamics
T. V. Zaqarashvili; B. Roberts
2006-02-24T23:59:59.000Z
The weakly nonlinear interaction of sound and linearly polarised Alfv{\\'e}n waves propagating in the same direction along an applied magnetic field is studied. It is found that a sound wave is coupled to the Alfv{\\'e}n wave with double period and wavelength when the sound and Alfv{\\'e}n speeds are equal. The Alfv{\\'e}n wave drives the sound wave through the ponderomotive force, while the sound wave returns energy back to the Alfv{\\'e}n wave through the parametric (swing) influence. As a result, the two waves alternately exchange their energy during propagation. The process of energy exchange is faster for waves with stronger amplitudes. The phenomenon can be of importance in astrophysical plasmas, including the solar atmosphere and solar wind.
Global coherence of dust density waves
Killer, Carsten; Melzer, André [Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, 17489 Greifswald (Germany)
2014-06-15T23:59:59.000Z
The coherence of self-excited three-dimensional dust density waves has been experimentally investigated by comparing global and local wave properties. For that purpose, three-dimensional dust clouds have been confined in a radio frequency plasma with thermophoretic levitation. Global wave properties have been measured from the line-of-sight integrated dust density obtained from homogenous light extinction measurements. Local wave properties have been obtained from thin, two-dimensional illuminated laser slices of the cloud. By correlating the simultaneous global and local wave properties, the spatial coherence of the waves has been determined. We find that linear waves with small amplitudes tend to be fragmented, featuring an incoherent wave field. Strongly non-linear waves with large amplitudes, however, feature a strong spatial coherence throughout the dust cloud, indicating a high level of synchronization.
SALTSTONE DISPOSAL FACILITY: DETERMINATION OF THE PROBABLE MAXIMUM WATER TABLE ELEVATION
Hiergesell, R
2005-04-01T23:59:59.000Z
A coverage depicting the configuration of the probable maximum water table elevation in the vicinity of the Saltstone Disposal Facility (SDF) was developed to support the Saltstone program. This coverage is needed to support the construction of saltstone vaults to assure that they remain above the maximum elevation of the water table during the Performance Assessment (PA) period of compliance. A previous investigation to calculate the historical high water table beneath the SDF (Cook, 1983) was built upon to incorporate new data that has since become available to refine that estimate and develop a coverage that could be extended to the perennial streams adjacent to the SDF. This investigation incorporated the method used in the Cook, 1983 report to develop an estimate of the probable maximum water table for a group of wells that either existed at one time at or near the SDF or which currently exist. Estimates of the probable maximum water table at these wells were used to construct 2D contour lines depicting this surface beneath the SDF and extend them to the nearby hydrologic boundaries at the perennial streams adjacent to the SDF. Although certain measures were implemented to assure that the contour lines depict a surface above which the water table will not rise, the exact elevation of this surface cannot be known with complete certainty. It is therefore recommended that the construction of saltstone vaults incorporate a vertical buffer of at least 5-feet between the base of the vaults and the depicted probable maximum water table elevation. This should provide assurance that the water table under the wet extreme climatic condition will never rise to intercept the base of a vault.
US Army Corps of Engineers
B8 Page 1 B8. Using CMS-Wave The most recent CMS-Wave code developed is Version 3.2. Several new capabilities and advanced features in this version include: · Full-plane wind-generation of waves · Automatic wave run-up calculation · Infra-gravity wave calculation · Nonlinear wave-wave interaction · Muddy
Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)
2012-12-15T23:59:59.000Z
Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.
Wave propagation in anisotropic viscoelasticity
Andrzej Hanyga
2015-04-30T23:59:59.000Z
We extend the theory of complete Bernstein functions to matrix-valued functions and apply it to analyze Green's function of an anisotropic multi-dimension\\-al linear viscoelastic problem. Green's function is given by the superposition of plane waves. Each plane wave is expressed in terms of matrix-valued attenuation and dispersion functions given in terms of a matrix-valued positive semi-definite Radon measure. More explicit formulae are obtained for 3D isotropic viscoelastic Green's functions. As an example of an anisotropic medium the transversely isotropic medium with a constant symmetry axis is considered.
Wave Energy | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTri GlobalJump to: navigation,Goff, 2002) | OpenEnergy AS Jump to:WaveWave
atmospheric gravity waves: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
gravity waves (AGWs). Satellite imagery shows evidence the characteristics of these waves. The favorable wave propagation conditions in 12;this region are illustrated 5...
anomalous spin waves: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
branches of wave dispersion: spin-electromagnetic plasma waves and self-consistent spin waves. Propagation of neutron beams through quantum plasmas is also considered....
Identifying two steps in the internal wave energy cascade
Sun, Oliver Ming-Teh
2010-01-01T23:59:59.000Z
1.1.1 The internal wave energy cascade . . . . . . .? ? , which contain only wave energy trav- eling upward anddistinction is made between wave energy propagating upward
Fundamentals of Traveling Wave Ion Mobility Spectrometry. | EMSL
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Fundamentals of Traveling Wave Ion Mobility Spectrometry. Fundamentals of Traveling Wave Ion Mobility Spectrometry. Abstract: Traveling-wave ion mobility spectrometry (TW IMS) is a...
MHK Technologies/New Knowledge Wind and Wave Renewable Mobile...
Wave Renewable Mobile Wind and Wave Power Plant Platform < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage New Knowledge Wind and Wave Renewable...
alfven wave spectrum: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
waves are easily excited by various processes. Linear waves propagate at the Alfv'en speed v Guedel, Manuel 14 Anisotropic weak turbulence of Alfven waves in collisionless...
alfven wave avalanches: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
waves are easily excited by various processes. Linear waves propagate at the Alfv'en speed v Guedel, Manuel 13 Anisotropic weak turbulence of Alfven waves in collisionless...
Texas at Austin, University of
(fast and slow) with differing polarization. The 4C, 3D ocean-bottom cable (OBC) multicomponent seismic and stratigraphic features within the gas-charged intervals. C- waves (Figure 3) penetrate these P-wave wipeout
Henning, F. D., E-mail: farranalfonso@gmail.com; Mace, R. L., E-mail: macer@ukzn.ac.za [School of Chemistry and Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000 (South Africa)
2014-04-15T23:59:59.000Z
Electromagnetic ion cyclotron (EMIC) waves in multi-ion species plasmas propagate in branches. Except for the branch corresponding to the heaviest ion species, which has only a resonance at its gyrofrequency, these branches are bounded below by a cutoff frequency and above by a resonant gyrofrequency. The condition for wave growth is determined by the thermal anisotropies of each ion species, j, which sets an upper bound, ?{sub j}{sup ?}, on the wave frequency below which that ion species contributes positively to the growth rate. It follows that the relative positions of the cutoffs and the critical frequencies ?{sub j}{sup ?} play a crucial role in determining whether a particular wave branch will be unstable. The effect of the magnetospheric ion abundances on the growth rate of each branch of the EMIC instability in a model where all the ion species have kappa velocity distributions is investigated by appealing to the above ideas. Using the variation of the cutoff frequencies predicted by cold plasma theory as a guide, optimal ion abundances that maximise the EMIC instability growth rate are sought. When the ring current is comprised predominantly of H{sup +} ions, all branches of the EMIC wave are destabilised, with the proton branch having the maximum growth rate. When the O{sup +} ion abundance in the ring current is increased, a decrease in the growth rate of the proton branch and cyclotron damping of the helium branch are observed. The oxygen branch, on the other hand, experiences an increase in the maximum growth rate with an increase in the O{sup +} ion abundance. When the ring current is comprised predominantly of He{sup +} ions, only the helium and oxygen branches of the EMIC wave are destabilised, with the helium branch having the maximum growth rate.
Wave VelocityWave Velocity Diff t f ti l l itDifferent from particle velocity
Yoo, S. J. Ben
Wave VelocityWave Velocity v=/T =f Diff t f ti l l itDifferent from particle velocity Depends on the medium in which the wave travelsDepends on the medium in which the wave travels stringaonvelocity F v of Waves11-8. Types of Waves Transverse wave Longitudinal wave Liu UCD Phy1B 2014 37 #12;Sound Wave
WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISION-LESS PLASMA
Cary, John R.
2012-01-01T23:59:59.000Z
case, the electrons have negative wave energy for 2w ne w wave energy for 2w .w > 0 nl Hence, unstable waves with negative phase velocity,
Einstein, Black Holes Gravitational Waves
Cook, Greg
1 #12;Einstein, Black Holes and Gravitational Waves Gregory B. Cook Wake Forest University 2 #12;Einstein's Miraculous Year: 1905 · Einstein, A. "¨Uber einen die Erzeugung und Verwandlung des Lichtes Concerning the Production and Transformation of Light. · Einstein, A. "¨Uber die von der molekularkinetischen
Wave functions of linear systems
Tomasz Sowinski
2007-06-05T23:59:59.000Z
Complete analysis of quantum wave functions of linear systems in an arbitrary number of dimensions is given. It is shown how one can construct a complete set of stationary quantum states of an arbitrary linear system from purely classical arguments. This construction is possible because for linear systems classical dynamics carries the whole information about quantum dynamics.
Ceyda Sanl?; Detlef Lohse; Devaraj van der Meer
2014-05-08T23:59:59.000Z
A hydrophilic floating sphere that is denser than water drifts to an amplitude maximum (antinode) of a surface standing wave. A few identical floaters therefore organize into antinode clusters. However, beyond a transitional value of the floater concentration $\\phi$, we observe that the same spheres spontaneously accumulate at the nodal lines, completely inverting the self-organized particle pattern on the wave. From a potential energy estimate we show (i) that at low $\\phi$ antinode clusters are energetically favorable over nodal ones and (ii) how this situation reverses at high $\\phi$, in agreement with the experiment.
Three dimensional winds: A maximum cross-correlation application to elastic lidar data
Buttler, W.T.
1996-05-01T23:59:59.000Z
Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar (light detection and ranging) data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three-dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain-following winds in the Rio Grande valley.
On the minimum and maximum mass of neutron stars and the delayed collapse
Strobel, K; Strobel, Klaus; Weigel, Manfred K.
2001-01-01T23:59:59.000Z
The minimum and maximum mass of protoneutron stars and neutron stars are investigated. The hot dense matter is described by relativistic (including hyperons) and non-relativistic equations of state. We show that the minimum mass ($\\sim$ 0.88 - 1.28 $M_{\\sun}$) of a neutron star is determined by the earliest stage of its evolution and is nearly unaffected by the presence of hyperons. The maximum mass of a neutron star is limited by the protoneutron star or hot neutron star stage. Further we find that the delayed collapse of a neutron star into a black hole during deleptonization is not only possible for equations of state with softening components, as for instance, hyperons, meson condensates etc., but also for neutron stars with a pure nucleonic-leptonic equation of state.
On the minimum and maximum mass of neutron stars and the delayed collapse
Klaus Strobel; Manfred K. Weigel
2000-12-14T23:59:59.000Z
The minimum and maximum mass of protoneutron stars and neutron stars are investigated. The hot dense matter is described by relativistic (including hyperons) and non-relativistic equations of state. We show that the minimum mass ($\\sim$ 0.88 - 1.28 $M_{\\sun}$) of a neutron star is determined by the earliest stage of its evolution and is nearly unaffected by the presence of hyperons. The maximum mass of a neutron star is limited by the protoneutron star or hot neutron star stage. Further we find that the delayed collapse of a neutron star into a black hole during deleptonization is not only possible for equations of state with softening components, as for instance, hyperons, meson condensates etc., but also for neutron stars with a pure nucleonic-leptonic equation of state.
Sullivan, Terry [Brookhaven National Lab. (BNL), Upton, NY (United States). Biological, Environmental, and Climate Sciences Dept.
2014-12-02T23:59:59.000Z
ZionSolutions is in the process of decommissioning the Zion Nuclear Power Plant in order to establish a new water treatment plant. There is some residual radioactive particles from the plant which need to be brought down to levels so an individual who receives water from the new treatment plant does not receive a radioactive dose in excess of 25 mrem/y?¹. The objectives of this report are: (a) To present a simplified conceptual model for release from the buildings with residual subsurface structures that can be used to provide an upper bound on contaminant concentrations in the fill material; (b) Provide maximum water concentrations and the corresponding amount of mass sorbed to the solid fill material that could occur in each building for use in dose assessment calculations; (c) Estimate the maximum concentration in a well located outside of the fill material; and (d) Perform a sensitivity analysis of key parameters.
Maximum-Entropy Meshfree Method for Compressible and Near-Incompressible Elasticity
Ortiz, A; Puso, M A; Sukumar, N
2009-09-04T23:59:59.000Z
Numerical integration errors and volumetric locking in the near-incompressible limit are two outstanding issues in Galerkin-based meshfree computations. In this paper, we present a modified Gaussian integration scheme on background cells for meshfree methods that alleviates errors in numerical integration and ensures patch test satisfaction to machine precision. Secondly, a locking-free small-strain elasticity formulation for meshfree methods is proposed, which draws on developments in assumed strain methods and nodal integration techniques. In this study, maximum-entropy basis functions are used; however, the generality of our approach permits the use of any meshfree approximation. Various benchmark problems in two-dimensional compressible and near-incompressible small strain elasticity are presented to demonstrate the accuracy and optimal convergence in the energy norm of the maximum-entropy meshfree formulation.
Hanel, Rudolf; Gell-Mann, Murray
2014-01-01T23:59:59.000Z
The maximum entropy principle (MEP) is a method for obtaining the most likely distribution functions of observables from statistical systems, by maximizing entropy under constraints. The MEP has found hundreds of applications in ergodic and Markovian systems in statistical mechanics, information theory, and statistics. For several decades there exists an ongoing controversy whether the notion of the maximum entropy principle can be extended in a meaningful way to non-extensive, non-ergodic, and complex statistical systems and processes. In this paper we start by reviewing how Boltzmann-Gibbs-Shannon entropy is related to multiplicities of independent random processes. We then show how the relaxation of independence naturally leads to the most general entropies that are compatible with the first three Shannon-Khinchin axioms, the (c,d)-entropies. We demonstrate that the MEP is a perfectly consistent concept for non-ergodic and complex statistical systems if their relative entropy can be factored into a general...
Exact computation of the Maximum Entropy Potential of spiking neural networks models
Cofre, Rodrigo
2014-01-01T23:59:59.000Z
Understanding how stimuli and synaptic connectivity in uence the statistics of spike patterns in neural networks is a central question in computational neuroscience. Maximum Entropy approach has been successfully used to characterize the statistical response of simultaneously recorded spiking neurons responding to stimuli. But, in spite of good performance in terms of prediction, the ?tting parameters do not explain the underlying mechanistic causes of the observed correlations. On the other hand, mathematical models of spiking neurons (neuro-mimetic models) provide a probabilistic mapping between stimulus, network architecture and spike patterns in terms of conditional proba- bilities. In this paper we build an exact analytical mapping between neuro-mimetic and Maximum Entropy models.
Maximum-entropy principle for static and dynamic high-field transport in semiconductors
Trovato, M. [Dipartimento di Matematica, Universita di Catania, Viale A. Doria, 95125 Catania (Italy); Reggiani, L. [Dipartimento di Ingegneria dell' Innovazione e Nanotechnology National Laboratory of CNR-INFM, Universita di Lecce, Via Arnesano s/n, 73100 Lecce (Italy)
2006-06-15T23:59:59.000Z
Within the maximum entropy principle we present a general theory able to provide, in a dynamical context, the macroscopic relevant variables for carrier transport under electric fields of arbitrary strength. For the macroscopic variables the linearized maximum entropy approach is developed including full-band effects within a total energy scheme. Under spatially homogeneous conditions, we construct a closed set of hydrodynamic equations for the small-signal (dynamic) response of the macroscopic variables. The coupling between the driving field and the energy dissipation is analyzed quantitatively by using an arbitrary number of moments of the distribution function. The theoretical approach is applied to n-Si at 300 K and is validated by comparing numerical calculations with ensemble Monte Carlo simulations and with experimental data.
Nonlinear Saturation of Vertically Propagating Rossby Waves
Giannitsis, Constantine
The interaction between vertical Rossby wave propagation and wave breaking is studied in the idealized context of a beta-plane channel model. Considering the problem of propagation through a uniform zonal flow in an ...
Arnold Schwarzenegger DEVELOPING WAVE ENERGY IN
Arnold Schwarzenegger Governor DEVELOPING WAVE ENERGY IN COASTAL CALIFORNIA: POTENTIAL SOCIO. Developing Wave Energy In Coastal California: Potential Socio-Economic And Environmental Effects. California-ECONOMIC AND ENVIRONMENTAL EFFECTS Prepared For: California Energy Commission Public Interest Energy Research Program
Mathematical aspects of surface water waves
Craig, Walter
questions remain. These have to do with the evolution of surface water waves, their approximation by model normally being chosen. Unless we are describing waves of a global extent, such as a tsunami, for our
Fracture compliance estimation using borehole tube waves
Bakku, Sudhish Kumar
We tested two models, one for tube-wave generation and the other for tube-wave attenuation at a fracture intersecting a borehole that can be used to estimate fracture compliance, fracture aperture, and lateral extent. In ...
On quantization of nondispersive wave packets
Altaisky, M. V. [Space Research Institute RAS, Profsoyuznaya 84/32, Moscow 117997 (Russian Federation)] [Space Research Institute RAS, Profsoyuznaya 84/32, Moscow 117997 (Russian Federation); Kaputkina, N. E. [National University of Science and Technology “MISIS” Leninsky prospect 4, Moscow 119049 (Russian Federation)] [National University of Science and Technology “MISIS” Leninsky prospect 4, Moscow 119049 (Russian Federation)
2013-10-15T23:59:59.000Z
Nondispersive wave packets are widely used in optics and acoustics. We found it interesting that such packets could be also a subject of quantum field theory. Canonical commutation relations for the nondispersive wave packets are constructed.
Wave Mechanics and General Relativity: A Rapprochement
Paul S. Wesson
2006-01-16T23:59:59.000Z
Using exact solutions, we show that it is in principle possible to regard waves and particles as representations of the same underlying geometry, thereby resolving the problem of wave-particle duality.
Wind effects on shoaling wave shape
Feddersen, F; Veron, F
2005-01-01T23:59:59.000Z
breaking in the presence of wind drift and swell. J. Fluidlin, 1995: Asymmetry of wind waves studied in a laboratorycoupling between swell and wind-waves. J. Phys. Oceanogr. ,
Carbon nanotube-guided thermopower waves
Choi, Wonjoon
Thermopower waves are a new concept for the direct conversion of chemical to electrical energy. A nanowire with large axial thermal diffusivity can accelerate a self-propagating reaction wave using a fuel coated along its ...
Oblique reflections of internal gravity wave beams
Karimi, Hussain H. (Hussain Habibullah)
2012-01-01T23:59:59.000Z
We study nonlinear effects in reflections of internal gravity wave beams in a continuously stratified liquid which are incident upon a uniform slope at an oblique angle. Wave motion in a stratified fluid medium is unique ...
Turbulent round jet under gravity waves
Ryu, Yong Uk
2002-01-01T23:59:59.000Z
The behavior of a neutrally buoyant horizontal turbulent round jet under a wavy environment was investigated. Progressive waves with different wave amplitudes in an intermediate water depth were used. The Particle Image Velocimetry (PIV) technique...
Gravitational waves from merging compact binaries
Hughes, Scott A.
Largely motivated by the development of highly sensitive gravitational-wave detectors, our understanding of merging compact binaries and the gravitational waves they generate has improved dramatically in recent years. ...
Analysis of optimum Lamb wave tuning
Shi, Yijun, 1970-
2002-01-01T23:59:59.000Z
Guided waves are of enormous interest in the nondestructive evaluation of thin-walled structures and layered media. Due to their dispersive and multi-modal nature, it is desirable to tune the waves by discriminating one ...
Hydrodynamic equations for electrons in graphene obtained from the maximum entropy principle
Barletti, Luigi, E-mail: luigi.barletti@unifi.it [Dipartimento di Matematica e Informatica “Ulisse Dini”, Università degli Studi di Firenze, Viale Morgagni 67/A, 50134 Firenze (Italy)
2014-08-15T23:59:59.000Z
The maximum entropy principle is applied to the formal derivation of isothermal, Euler-like equations for semiclassical fermions (electrons and holes) in graphene. After proving general mathematical properties of the equations so obtained, their asymptotic form corresponding to significant physical regimes is investigated. In particular, the diffusive regime, the Maxwell-Boltzmann regime (high temperature), the collimation regime and the degenerate gas limit (vanishing temperature) are considered.
REMARKS ON THE MAXIMUM ENTROPY METHOD APPLIED TO FINITE TEMPERATURE LATTICE QCD.
UMEDA, T.; MATSUFURU, H.
2005-07-25T23:59:59.000Z
We make remarks on the Maximum Entropy Method (MEM) for studies of the spectral function of hadronic correlators in finite temperature lattice QCD. We discuss the virtues and subtlety of MEM in the cases that one does not have enough number of data points such as at finite temperature. Taking these points into account, we suggest several tests which one should examine to keep the reliability for the results, and also apply them using mock and lattice QCD data.
Towards the application of the Maximum Entropy Method to finite temperature Upsilon Spectroscopy
M. Oevers; C. Davies; J. Shigemitsu
2000-09-22T23:59:59.000Z
According to the Narnhofer Thirring Theorem interacting systems at finite temperature cannot be described by particles with a sharp dispersion law. It is therefore mandatory to develop new methods to extract particle masses at finite temperature. The Maximum Entropy method offers a path to obtain the spectral function of a particle correlation function directly. We have implemented the method and tested it with zero temperature Upsilon correlation functions obtained from an NRQCD simulation. Results for different smearing functions are discussed.
Maximum entropy deconvolution of resonant inelastic x-ray scattering spectra
J. Laverock; A. R. H. Preston; D. Newby Jr; K. E. Smith; S. B. Dugdale
2012-02-10T23:59:59.000Z
Resonant inelastic x-ray scattering (RIXS) has become a powerful tool in the study of the electronic structure of condensed matter. Although the linewidths of many RIXS features are narrow, the experimental broadening can often hamper the identification of spectral features. Here, we show that the Maximum Entropy technique can successfully be applied in the deconvolution of RIXS spectra, improving the interpretation of the loss features without a severe increase in the noise ratio.
Remarks on the Maximum Entropy Method applied to finite temperature lattice QCD
Takashi Umeda; Hideo Matsufuru
2005-10-05T23:59:59.000Z
We make remarks on the Maximum Entropy Method (MEM) for studies of the spectral function of hadronic correlators in finite temperature lattice QCD. We discuss the virtues and subtlety of MEM in the cases that one does not have enough number of data points such as at finite temperature. Taking these points into account, we suggest several tests which one should examine to keep the reliability for the results, and also apply them using mock and lattice QCD data.
Holzer, Mark; Primeau, Francois W; Smethie, William M; Khatiwala, Samar
2010-01-01T23:59:59.000Z
Gull (1991), Bayesian maximum entropy image reconstruction,F. Primeau (2006), A maximum entropy approach to water massSouth- ern Ocean? A maximum entropy approach to global water
Pflugrath, Brett D.; Brown, Richard S.; Carlson, Thomas J.
2012-03-01T23:59:59.000Z
This study investigated the maximum depth at which juvenile Chinook salmon Oncorhynchus tshawytscha can acclimate by attaining neutral buoyancy. Depth of neutral buoyancy is dependent upon the volume of gas within the swim bladder, which greatly influences the occurrence of injuries to fish passing through hydroturbines. We used two methods to obtain maximum swim bladder volumes that were transformed into depth estimations - the increased excess mass test (IEMT) and the swim bladder rupture test (SBRT). In the IEMT, weights were surgically added to the fishes exterior, requiring the fish to increase swim bladder volume in order to remain neutrally buoyant. SBRT entailed removing and artificially increasing swim bladder volume through decompression. From these tests, we estimate the maximum acclimation depth for juvenile Chinook salmon is a median of 6.7m (range = 4.6-11.6 m). These findings have important implications to survival estimates, studies using tags, hydropower operations, and survival of juvenile salmon that pass through large Kaplan turbines typical of those found within the Columbia and Snake River hydropower system.
Wave-driven Countercurrent Plasma Centrifuge
A.J. Fetterman and N.J. Fisch
2009-03-20T23:59:59.000Z
A method for driving rotation and a countercurrent flow in a fully ionized plasma centrifuge is described. The rotation is produced by radiofrequency waves near the cyclotron resonance. The wave energy is transferred into potential energy in a manner similar to the ? channeling effect. The countercurrent flow may also be driven by radiofrequency waves. By driving both the rotation and the flow pattern using waves instead of electrodes, physical and engineering issues may be avoided.
Wave Propagation in Fractured Poroelastic Media
Seismic wave propagation through fractures and cracks is an important subject in exploration and production geophysics, earthquake seismology and mining.
Gravitational waves from a test particle scattered by a neutron star: Axial mode case
Kazuhiro Tominaga; Motoyuki Saijo; Kei-ichi Maeda
1999-09-20T23:59:59.000Z
Using a metric perturbation method, we study gravitational waves from a test particle scattered by a spherically symmetric relativistic star. We calculate the energy spectrum and the waveform of gravitational waves for axial modes. Since metric perturbations in axial modes do not couple to the matter fluid of the star, emitted waves for a normal neutron star show only one peak in the spectrum, which corresponds to the orbital frequency at the turning point, where the gravitational field is strongest. However, for an ultracompact star (the radius $R \\lesssim 3M$), another type of resonant periodic peak appears in the spectrum. This is just because of an excitation by a scattered particle of axial quasinormal modes, which were found by Chandrasekhar and Ferrari. This excitation comes from the existence of the potential minimum inside of a star. We also find for an ultracompact star many small periodic peaks at the frequency region beyond the maximum of the potential, which would be due to a resonance of two waves reflected by two potential barriers (Regge-Wheeler type and one at the center of the star). Such resonant peaks appear neither for a normal neutron star nor for a Schwarzschild black hole. Consequently, even if we analyze the energy spectrum of gravitational waves only for axial modes, it would be possible to distinguish between an ultracompact star and a normal neutron star (or a Schwarzschild black hole).
Comparison of P-wave and S-wave data processed by DIP moveout
Al-Misnid, Abdulaziz Mugbel
1994-01-01T23:59:59.000Z
of compressional (P) and shear (S) wave data in a fractured reservoir can show whether amplitude anomalies on the P-wave section are associated with the presence of gas or change of lithology. The P-wave and S-wave data selected for this study were shot in Burleson...
High amplitude wave propagation in collapsible tubes. II. Forerunners and high amplitude waves
Paris-Sud XI, UniversitÃ© de
773 High amplitude wave propagation in collapsible tubes. II. Forerunners and high amplitude waves that, under certain circumstances, a pressure wave of large amplitude which propagates in a fluid feature of such a shock wave propagation inside an initially collapsed tube is the presence ofwavelets
Thompson/Ocean 420/Winter 2004 2D waves 1 Two-dimensional wave propagation
Thompson, LuAnne
Thompson/Ocean 420/Winter 2004 2D waves 1 Two-dimensional wave propagation So far we have talked about wave propagation in one-dimension. For two or three spatial dimensions, we vectorize our ideas propagation. For surface waves, there is no vertical propagation, and we are only concerned with the two
WAVE HEIGHTS IN A 4D OCEAN WAVE FIELD Paul C. Liu
WAVE HEIGHTS IN A 4D OCEAN WAVE FIELD Paul C. Liu NOAA Great Lakes Environmental Research a preliminary examination and analysis of a small suite of 4-D wave data to explore what new insight century. We feel it is timely to encourage further 4-D ocean wave measurement and thereby facilitate fresh
Wave Front Interaction Model of Stabilized Propagating Wave Segments Vladimir S. Zykov1
Showalter, Kenneth
Wave Front Interaction Model of Stabilized Propagating Wave Segments Vladimir S. Zykov1 and Kenneth; published 14 February 2005) A wave front interaction model is developed to describe the relationship between excitability and the size and shape of stabilized wave segments in a broad class of weakly excitable media
Wave Turbulence in Superfluid 4 Energy Cascades, Rogue Waves & Kinetic Phenomena
Fominov, Yakov
Outline Wave Turbulence in Superfluid 4 He: Energy Cascades, Rogue Waves & Kinetic Phenomena Conference, Chernogolovka, 3 August 2009 McClintock Efimov Ganshin Kolmakov Mezhov-Deglin Wave Turbulence in Superfluid 4 He #12;Outline Outline 1 Introduction Motivation 2 Modelling wave turbulence Need for models
Wave-pinned filaments of scroll waves Tams Bnsgi, Jr., Kevin J. Meyer, and Oliver Steinbocka
Steinbock, Oliver
Wave-pinned filaments of scroll waves Tamás Bánsági, Jr., Kevin J. Meyer, and Oliver Steinbocka Received 5 November 2007; accepted 26 December 2007; published online 6 March 2008 Scroll waves are three can be pinned to the wake of traveling wave pulses. This pinning is studied in experiments with the 1
Measurement of sound speed vs. depth in South Pole ice: pressure waves and shear waves
Klein, Spencer
2010-01-01T23:59:59.000Z
waves generated by the thermoacoustic mechanism, little workproduction by the thermoacoustic mechanism is suppressed,
Wave Impact Study on a Residential Building Wave Impact Study on a Residential Building
Cox, Dan
Wave Impact Study on a Residential Building Paper: Wave Impact Study on a Residential Building John residential light- frame wood buildings and wave and surge loading be- cause often little is left residential structures and wave loading. To do this, one-sixth scale residen- tial building models typical
Beauty waves: an artistic representation of ocean waves using Bezier curves
Faulkner, Jay Allen
2007-04-25T23:59:59.000Z
In this thesis, we present a method for computing an artistic representation of ocean waves using Bezier curves. Wave forms are loosely based on procedural wave models and are designed to emulate those found in both art and nature. The wave forms...
Autoresonance of coupled nonlinear waves L. Friedland
Friedland, Lazar
wave train solutions of the decoupled problem. At the same time, the waves are globally phase locked, allowing the continuation of the phase locking between the waves despite the variation of system's param and sustaining this multidimensional autoresonance are the internal reso- nant excitation of one of the coupled
EFFECTS OF SOUND WAVES ON YOUNG SALMON
EFFECTS OF SOUND WAVES ON YOUNG SALMON Marine Biological Laboratory X. 1 33 R A. RTT ir.':; WOODS instantaneously to sounds. It was con- were tested in an experimental tank and in eluded that sound waves were, Wash . sound studies conducted under the above contract are terminated. #12;EFFECTS OF SOUND WAVES
Coupled Parabolic Equations for Wave Propagation
Zhao, Hongkai
Coupled Parabolic Equations for Wave Propagation Kai Huang, Knut Solna and Hongkai Zhao #3; April simulation of wave propagation over long distances. The coupled parabolic equations are derived from a two algorithms are important in order to understand wave propagation in complex media. Resolving the wavelength
Solitary waves propagating over variable Roger Grimshaw
Solitary waves propagating over variable topography Roger Grimshaw Loughborough University waves that can propagate steadily over long distances. They were first observed by Russell in 1837 in a now famous report [26] on his observations of a solitary wave propagating along a Scottish canal
Seminario de Matemtica Aplicada "Renowable wave energy
Tradacete, Pedro
Seminario de Matemática Aplicada "Renowable wave energy: potencial and technical challenges Abstract: Among the various renewable energy sources, ocean wave energy has been only recently investiga will be at first to introduce the potential of wave energy, as a significant, and often neglected, contributor
Wave propagation Remco Hartkamp (University of Twente)
Entekhabi, Dara
) waves Sound: 20 Hz 20 kHz Gas: P Liquid: P Plasma: P Solid: P & S #12;Stretched string example 1D wave Dispersion: Waves with different wavelengths propagate at different speeds 6 k c k k Shallow water: c gh mJ K material parameter (related to the strain saturation of the material) det FJ bulk modulus
Multi-reflective acoustic wave device
Andle, Jeffrey C.
2006-02-21T23:59:59.000Z
An acoustic wave device, which utilizes multiple localized reflections of acoustic wave for achieving an infinite impulse response while maintaining high tolerance for dampening effects, is disclosed. The device utilized a plurality of electromechanically significant electrodes disposed on most of the active surface. A plurality of sensors utilizing the disclosed acoustic wave mode device are also described.
Wave guides: vacuum w/ tube of conductor
Hart, Gus
Wave guides: vacuum w/ tube of conductor boundary conditions for conductor Properties: non-transverse waves except TEM mode in coaxial cable speed normal modes (from Liouville problem) TE or TM TEM for coaxial cable cuto frequency otherwise evanescent waves separation into and components with 1 #12;B
WAVE GENERATIONS FROM CONFINED EXPLOSIONS IN ROCKS
Stewart, Sarah T.
WAVE GENERATIONS FROM CONFINED EXPLOSIONS IN ROCKS C. L. Liu and Thomas J. Ahrens Seismological Laboratory, California Institute of Technology, Pasadena, CA 91125 In order to record P- and S-waves on the interactions between incident P- and SV-waves and free-surfaces of rocks. The relations between particle
Wave Packets and Turbulent Peter Jordan1
Dabiri, John O.
Wave Packets and Turbulent Jet Noise Peter Jordan1 and Tim Colonius2 1 D´epartement Fluides-control efforts is incomplete. Wave packets are intermittent, advecting disturbances that are correlated over review evidence of the existence, energetics, dynamics, and acous- tic efficiency of wave packets. We
EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR
Karney, Charles
EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR A WEAKLY RELATIVISTIC PLASMA by S.C. CHIU, C.F.F. KARNEY: http://charles.karney.info/biblio/chiu94.html #12;Chiu e t al. THE EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR A WEAKLY RELATIVISTIC PLASMA THE EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR A WEAKLY
Visualizing the kinematics of relativistic wave packets
Bernd Thaller
2004-09-14T23:59:59.000Z
This article investigates some solutions of the time-dependent free Dirac equation. Visualizations of these solutions immediately reveal strange phenomena that are caused by the interference of positive- and negative-energy waves. The effects discussed here include the Zitterbewegung, the opposite direction of momentum and velocity in negative-energy wave packets, and the superluminal propagation of the wave packet's local maxima.
Hybrid wave model and its applications
Yang, Jun
1998-01-01T23:59:59.000Z
A nonlinear hybrid wave model (HWM) is developed. It uses the conventional mode-coupling method (MCM) and the phase modulation method (PMM) to address the nonlinear interactions between free-wave components in an ocean wave field. The PMM is a...
Airborne observations of the kinematics and statistics of breaking waves
Kleiss, Jessica M.
2009-01-01T23:59:59.000Z
E. M. Janssen, 1996: Wave energy dissipation by whitecaps.waves: Surface impulse and wave energy dissipation rates. J.to the ocean, dissipating wave energy that is then available
ITB KNAW UTwente Lectures on Free Surface Waves
Al Hanbali, Ahmad
, Acknowledgment Surface waves are phenomena that are characterised by the dynamic interplay between linear.3 Linear Dispersive wave model . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.4 Wave groupsITB KNAW UTwente Lectures on Free Surface Waves Brenny van Groesen, Applied Analysis & Mathematical
Effect of immiscible liquid contaminants on P-wave transmission through natural aquifer samples
Geller, Jil T.; Ajo-Franklin, Jonathan B.; Majer, Ernest L.
2003-01-31T23:59:59.000Z
We performed core-scale laboratory experiments to examine the effect of non-aqueous phase liquid (NAPL) contaminants on P-wave velocity and attenuation in heterogeneous media. This work is part of a larger project to develop crosswell seismic methods for minimally invasive NAPL detection. The test site is the former DOE Pinellas Plant in Florida, which has known NAPL contamination in the surficial aquifer. Field measurements revealed a zone of anomalously high seismic attenuation, which may be due to lithology and/or contaminants (NAPL or gas phase). Intact core was obtained from the field site, and P-wave transmission was measured by the pulse-transmission technique with a 500 kHz transducer. Two types of samples were tested: a clean fine sand from the upper portion of the surficial aquifer, and clayey-silty sand with shell fragments and phosphate nodules from the lower portion. Either NAPL trichloroethene or toluene was injected into the initially water-saturated sample. Maximum NAPL saturations ranged from 30 to 50% of the pore space. P-wave velocity varied by approximately 4% among the water-saturated samples, while velocities decreased by 5 to 9% in samples at maximum NAPL saturation compared to water-saturated conditions. The clay and silt fraction as well as the larger scatterers in the clayey-silty sands apparently caused greater P-wave attenuation compared to the clean sand. The presence of NAPLs caused a 34 to 54% decrease in amplitudes of the first arrival. The central frequency of the transmitted energy ranged from 85 to 200 kHz, and was sensitive to both grain texture and presence of NAPL. The results are consistent with previous trends observed in homogeneous sand packs. More data will be acquired to interpret P-wave tomograms from crosswell field measurements, determine the cause of high attenuation observed in the field data and evaluate the sensitivity of seismic methods for NAPL detection.
Traveling wave device for combining or splitting symmetric and asymmetric waves
Möbius, Arnold (Eggenstein, DE); Ives, Robert Lawrence (Saratoga, CA)
2005-07-19T23:59:59.000Z
A traveling wave device for the combining or splitting of symmetric and asymmetric traveling wave energy includes a feed waveguide for traveling wave energy, the feed waveguide having an input port and a launching port, a reflector for coupling wave energy between the feed waveguide and a final waveguide for the collection and transport of wave energy to or from the reflector. The power combiner has a launching port for symmetrical waves which includes a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric waves which includes a sawtooth rotated about a central axis.
Wave turbulent statistics in non-weak wave turbulence
Naoto Yokoyama
2011-05-08T23:59:59.000Z
In wave turbulence, it has been believed that statistical properties are well described by the weak turbulence theory, in which nonlinear interactions among wavenumbers are assumed to be small. In the weak turbulence theory, separation of linear and nonlinear time scales derived from the weak nonlinearity is also assumed. However, the separation of the time scales is often violated even in weak turbulent systems where the nonlinear interactions are actually weak. To get rid of this inconsistency, closed equations are derived without assuming the separation of the time scales in accordance with Direct-Interaction Approximation (DIA), which has been successfully applied to Navier--Stokes turbulence. The kinetic equation of the weak turbulence theory is recovered from the DIA equations if the weak nonlinearity is assumed as an additional assumption. It suggests that the DIA equations is a natural extension of the conventional kinetic equation to not-necessarily-weak wave turbulence.
Damage Detection in Plate Structures using Guided Ultrasonic Waves
Jarmer, Gregory James Sylvester
Guided Wave Structural Health Monitoring. ” Ultrasonics 50 (to Structural Health Monitoring. ” Philosophicalfor Guided-wave Structural Health Monitoring. ” Structural
Construction of KP solitons from wave patterns
Sarbarish Chakravarty; Yuji Kodama
2013-09-10T23:59:59.000Z
We often observe that waves on the surface of shallow water form complex web-like patterns. They are examples of nonlinear waves, and these patterns are generated by nonlinear interactions among several obliquely propagating waves. In this note, we discuss how to construct an exact soliton solution of the KP equation from such web-pattern of shallow water wave. This can be regarded as an "inverse problem" in the sense that by measuring certain metric data of the solitary waves in the given pattern, it is possible to construct an exact KP soliton solution which can describe the non-stationary dynamics of the pattern.
Thermal Gravitational Waves from Primordial Black Holes
C. Sivaram; Kenath Arun
2010-05-19T23:59:59.000Z
Thermal gravitational waves can be generated in various sources such as, in the cores of stars, white dwarfs and neutron stars due to the fermion collisions in the dense degenerate Fermi gas. Such high frequency thermal gravitational waves can also be produced during the collisions in a gamma ray burst or during the final stages of the evaporation of primordial black holes. Here we estimate the thermal gravitational waves from primordial black holes and estimate the integrated energy of the gravitational wave emission over the entire volume of the universe and over Hubble time. We also estimate the gravitational wave flux from gamma ray bursts and jets.
Refractive gravitational waves and quantum fluctuations
John W. Barrett
2000-11-14T23:59:59.000Z
Refractive gravitational waves are a generalisation of impulsive waves on a null hypersurface in which the metric is discontinuous but a weaker continuity condition for areas holds. A simple example of a plane wave is examined in detail and two arguments are given that this should be considered a solution of Einstein's vacuum field equations. The study of these waves is motivated by quantum gravity, where the refractive plane waves are considered as elementary quantum fluctuations and the `area geometry' of a null hypersurface plays a primary role.
Matter Wave Radiation Leading to Matter Teleportation
Yong-Yi Huang
2015-02-12T23:59:59.000Z
The concept of matter wave radiation is put forward, and its equation is established for the first time. The formalism solution shows that the probability density is a function of displacement and time. A free particle and a two-level system are reinvestigated considering the effect of matter wave radiation. Three feasible experimental designs, especially a modified Stern-Gerlach setup, are proposed to verify the existence of matter wave radiation. Matter wave radiation effect in relativity has been formulated in only a raw formulae, which offers another explanation of Lamb shift. A possible mechanics of matter teleportation is predicted due to the effect of matter wave radiation.
Ponderomotive Forces On Waves In Modulated Media
Dodin, I.Y; Fisch, Nathaniel
2014-02-28T23:59:59.000Z
Nonlinear interactions of waves via instantaneous cross-phase modulation can be cast in the same way as ponderomotive wave-particle interactions in high-frequency electromagnetic fi eld. The ponderomotive effect arises when rays of a probe wave scatter off perturbations of the underlying medium produced by a second, modulation wave, much like charged particles scatter off a quasiperiodic field. Parallels with the point-particle dynamics, which itself is generalized by this theory, lead to new methods of wave manipulation, including asymmetric barriers for light.
Kinematic dynamo induced by helical waves
Wei, Xing
2014-01-01T23:59:59.000Z
We investigate numerically the kinematic dynamo induced by the superposition of two helical waves in a periodic box as a simplified model to understand the dynamo action in astronomical bodies. The effects of magnetic Reynolds number, wavenumber and wave frequency on the dynamo action are studied. It is found that this helical-wave dynamo is a slow dynamo. There exists an optimal wavenumber for the dynamo growth rate. A lower wave frequency facilitates the dynamo action and the oscillations of magnetic energy emerge at some particular wave frequencies.
Gravitational waves from perturbed stars
Valeria Ferrari
2011-05-09T23:59:59.000Z
Non radial oscillations of neutron stars are associated with the emission of gravitational waves. The characteristic frequencies of these oscillations can be computed using the theory of stellar perturbations, and they are shown to carry detailed information on the internal structure of the emitting source. Moreover, they appear to be encoded in various radiative processes, as for instance in the tail of the giant flares of Soft Gamma Repeaters. Thus, their determination is central to the theory of stellar perturbation. A viable approach to the problem consists in formulating this theory as a problem of resonant scattering of gravitational waves incident on the potential barrier generated by the spacetime curvature. This approach discloses some unexpected correspondences between the theory of stellar perturbations and the theory of quantum mechanics, and allows us to predict new relativistic effects.
Reconstruction of nonlinear wave propagation
Fleischer, Jason W; Barsi, Christopher; Wan, Wenjie
2013-04-23T23:59:59.000Z
Disclosed are systems and methods for characterizing a nonlinear propagation environment by numerically propagating a measured output waveform resulting from a known input waveform. The numerical propagation reconstructs the input waveform, and in the process, the nonlinear environment is characterized. In certain embodiments, knowledge of the characterized nonlinear environment facilitates determination of an unknown input based on a measured output. Similarly, knowledge of the characterized nonlinear environment also facilitates formation of a desired output based on a configurable input. In both situations, the input thus characterized and the output thus obtained include features that would normally be lost in linear propagations. Such features can include evanescent waves and peripheral waves, such that an image thus obtained are inherently wide-angle, farfield form of microscopy.
Majidi-Ahy, Gholamreza (Sunnyvale, CA); Bloom, David M. (Portola Valley, CA)
1991-01-01T23:59:59.000Z
A millimeter-wave active probe for use in injecting signals with frequencies above 50GHz to millimeter-wave and ultrafast devices and integrated circuits including a substrate upon which a frequency multiplier consisting of filter sections and impedance matching sections are fabricated in uniplanar transmission line format. A coaxial input and uniplanar 50 ohm transmission line couple an approximately 20 GHz input signal to a low pass filter which rolls off at approximately 25 GHz. An input impedance matching section couples the energy from the low pass filter to a pair of matched, antiparallel beam lead diodes. These diodes generate odd-numberd harmonics which are coupled out of the diodes by an output impedance matching network and bandpass filter which suppresses the fundamental and third harmonics and selects the fifth harmonic for presentation at an output.
Freak waves in white dwarfs and magnetars
Sabry, R. [Theoretical Physics Group, Physics Department, Faculty of Science, Damietta University, New Damietta 34517 (Egypt); Department of Physics, College of Science and Humanitarian Studies, Salman bin Abdulaziz University, Alkharj (Saudi Arabia); International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Moslem, W. M. [International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt); Centre for Theoretical Physics, The British University in Egypt (BUE), El-Shorouk City, Cairo (Egypt); Shukla, P. K. [International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Department of Mechanical and Aerospace Engineering and Center for Energy Research, University of California, San Diego, La Jolla, California 92093 (United States)
2012-12-15T23:59:59.000Z
We report properties of ion acoustic freak waves that propagate in a plasma composed of warm ions and ultrarelativistic electrons and positrons. The dynamics of the nonlinear freak waves is governed by the nonlinear Schroedinger equation. The possible region for the freak waves to exist is defined precisely for typical parameters of white dwarfs and magnetars corona. It is found that for low wave number, the nonlinear ion-acoustic wave packets are structurally stable in magnetars corona than in white dwarfs. However, for large wave numbers the situation is opposite. The critical wave number threshold (k{sub c}), which indicates where the modulational instability sets in, is defined for both applications. It is seen that near to k{sub c} the freak wave amplitude becomes high, but it decreases whenever we stepped away from k{sub c}. For the wave numbers close to k{sub c}, the increase of the unperturbed density ratio of positrons-to-electrons ({beta}) would lead to increase the freak wave amplitude, but for larger wave numbers the amplitude decreases with the increase of {beta}.
The Nature of Running Penumbral Waves Revealed
D. Shaun Bloomfield; Andreas Lagg; Sami K. Solanki
2007-09-24T23:59:59.000Z
We seek to clarify the nature of running penumbral (RP) waves: are they chromospheric trans-sunspot waves or a visual pattern of upward-propagating waves? Full Stokes spectropolarimetric time series of the photospheric Si I 10827 \\AA line and the chromospheric He I 10830 \\AA multiplet were inverted using a Milne-Eddington atmosphere. Spatial pixels were paired between the outer umbral/inner penumbral photosphere and the penumbral chromosphere using inclinations retrieved by the inversion and the dual-height pairings of line-of-sight velocity time series were studied for signatures of wave propagation using a Fourier phase difference analysis. The dispersion relation for radiatively cooling acoustic waves, modified to incorporate an inclined propagation direction, fits well the observed phase differences between the pairs of photospheric and chromospheric pixels. We have thus demonstrated that RP waves are in effect low-beta slow-mode waves propagating along the magnetic field.
Corvino's construction using Brill waves
Domenico Giulini; Gustav Holzegel
2005-08-17T23:59:59.000Z
For two-black-hole time-symmetric initial data we consider the Corvino construction of gluing an exact Schwarzschild end. We propose to do this by using Brill waves. We address the question of whether this method can be used to reduce the overall energy, which seems to relate to the question of whether it can reduce the amount of `spurious' gravitational radiation. We find a positive answer at first order in the inverse gluing radius.
Sequentially pulsed traveling wave accelerator
Caporaso, George J. (Livermore, CA); Nelson, Scott D. (Patterson, CA); Poole, Brian R. (Tracy, CA)
2009-08-18T23:59:59.000Z
A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.
Chen, Sheng
Blind Joint Maximum Likelihood Channel Estimation and Data Detection for Single-Input Multiple of Southampton, Southampton SO17 1BJ, U.K. Abstract--A blind adaptive scheme is proposed for joint maximum. A simulation example is used to demon- strate the effectiveness of this joint ML optimization scheme for blind
Mitchell, Richard
On Maximum Available Feedback and PID Control - 1 IEEE SMC UK&RI Applied Cybernetics Â© Dr Richard Mitchell 2005 ON MAXIMUM AVAILABLE FEEDBACK AND PID CONTROL Dr Richard Mitchell, Cybernetics, University frequencies A recent IEEE SMC Paper describes a robust PID controller whose phase is flat at key frequencies
Chapman, Patrick
Abstract--The many different techniques for maximum power point tracking of photovoltaic arrays on implementation. This manuscript should serve as a convenient reference for future work in photovoltaic power generation. Index Terms--maximum power point tracking, MPPT, photovoltaic, PV. I. INTRODUCTION RACKING
Wave propagation in axion electrodynamics
Yakov Itin
2007-06-20T23:59:59.000Z
In this paper, the axion contribution to the electromagnetic wave propagation is studied. First we show how the axion electrodynamics model can be embedded into a premetric formalism of Maxwell electrodynamics. In this formalism, the axion field is not an arbitrary added Chern-Simon term of the Lagrangian, but emerges in a natural way as an irreducible part of a general constitutive tensor.We show that in order to represent the axion contribution to the wave propagation it is necessary to go beyond the geometric approximation, which is usually used in the premetric formalism. We derive a covariant dispersion relation for the axion modified electrodynamics. The wave propagation in this model is studied for an axion field with timelike, spacelike and null derivative covectors. The birefringence effect emerges in all these classes as a signal of Lorentz violation. This effect is however completely different from the ordinary birefringence appearing in classical optics and in premetric electrodynamics. The axion field does not simple double the ordinary light cone structure. In fact, it modifies the global topological structure of light cones surfaces. In CFJ-electrodynamics, such a modification results in violation of causality. In addition, the optical metrics in axion electrodynamics are not pseudo-Riemannian. In fact, for all types of the axion field, they are even non-Finslerian.
Topological Aspects of Wave Propagation
Carlos Valero
2014-06-13T23:59:59.000Z
In the context of wave propagation on a manifold X, the characteristic functions are real valued functions on cotangent bundle of X that specify the allowable phase velocities of the waves. For certain classes of differential operators (e.g Maxwell's Equations) the associated characteristic functions have singularities. These singularities account for phenomena like conical refraction and the transformation of longitudinal waves into transversal ones (or viceversa). For a specific class of differential operators on surface, we prove that the singularities of the characteristic functions can be accounted from purely topological considerations. We also prove that there is a natural way to desingularsize the characteristic functions, and observe that this fact and Morse Theory establishes a specific connection between singularities and critical points of these functions. The relation between characteristic functions and differential operators is obtained through what is known as the symbol of the operator. We establish a connection between these symbols and holomorphic vector fields, which will provide us with symbols whose characteristic functions have interesting singularity sets.
Pražnikar, Jure [Institute Jožef Stefan, Jamova 39, 1000 Ljubljana (Slovenia); University of Primorska, (Slovenia); Turk, Dušan, E-mail: dusan.turk@ijs.si [Institute Jožef Stefan, Jamova 39, 1000 Ljubljana (Slovenia); Center of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, (Slovenia)
2014-12-01T23:59:59.000Z
The maximum-likelihood free-kick target, which calculates model error estimates from the work set and a randomly displaced model, proved superior in the accuracy and consistency of refinement of crystal structures compared with the maximum-likelihood cross-validation target, which calculates error estimates from the test set and the unperturbed model. The refinement of a molecular model is a computational procedure by which the atomic model is fitted to the diffraction data. The commonly used target in the refinement of macromolecular structures is the maximum-likelihood (ML) function, which relies on the assessment of model errors. The current ML functions rely on cross-validation. They utilize phase-error estimates that are calculated from a small fraction of diffraction data, called the test set, that are not used to fit the model. An approach has been developed that uses the work set to calculate the phase-error estimates in the ML refinement from simulating the model errors via the random displacement of atomic coordinates. It is called ML free-kick refinement as it uses the ML formulation of the target function and is based on the idea of freeing the model from the model bias imposed by the chemical energy restraints used in refinement. This approach for the calculation of error estimates is superior to the cross-validation approach: it reduces the phase error and increases the accuracy of molecular models, is more robust, provides clearer maps and may use a smaller portion of data for the test set for the calculation of R{sub free} or may leave it out completely.
Victoria, University of
On the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy On the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy Industry Effective, economic extraction of ocean wave energy requires an intimate under- standing of the ocean wave
A New Maximum-Likelihood Change Estimator for Two-Pass SAR Coherent Change Detection.
Wahl, Daniel E.; Yocky, David A.; Jakowatz, Charles V,
2014-09-01T23:59:59.000Z
In this paper, we derive a new optimal change metric to be used in synthetic aperture RADAR (SAR) coherent change detection (CCD). Previous CCD methods tend to produce false alarm states (showing change when there is none) in areas of the image that have a low clutter-to-noise power ratio (CNR). The new estimator does not suffer from this shortcoming. It is a surprisingly simple expression, easy to implement, and is optimal in the maximum-likelihood (ML) sense. The estimator produces very impressive results on the CCD collects that we have tested.
Dynamics of multi-modes maximum entangled coherent state over amplitude damping channel
A. El Allati; Y. Hassouni; N. Metwally
2012-02-18T23:59:59.000Z
The dynamics of maximum entangled coherent state travels through an amplitude damping channel is investigated. For small values of the transmissivity rate the travelling state is very fragile to this noise channel, where it suffers from the phase flip error with high probability. The entanglement decays smoothly for larger values of the transmissivity rate and speedily for smaller values of this rate. As the number of modes increases, the travelling state over this noise channel loses its entanglement hastily. The odd and even states vanish at the same value of the field intensity.
On Weyl channels being covariant with respect to the maximum commutative group of unitaries
G. G. Amosov
2006-08-10T23:59:59.000Z
We investigate the Weyl channels being covariant with respect to the maximum commutative group of unitary operators. This class includes the quantum depolarizing channel and the "two-Pauli" channel as well. Then, we show that our estimation of the output entropy for a tensor product of the phase damping channel and the identity channel based upon the decreasing property of the relative entropy allows to prove the additivity conjecture for the minimal output entropy for the quantum depolarizing channel in any prime dimesnsion and for the "two Pauli" channel in the qubit case.
A reliable, fast and low cost maximum power point tracker for photovoltaic applications
Enrique, J.M.; Andujar, J.M.; Bohorquez, M.A. [Departamento de Ingenieria Electronica, de Sistemas Informaticos y Automatica, Universidad de Huelva (Spain)
2010-01-15T23:59:59.000Z
This work presents a new maximum power point tracker system for photovoltaic applications. The developed system is an analog version of the ''P and O-oriented'' algorithm. It maintains its main advantages: simplicity, reliability and easy practical implementation, and avoids its main disadvantages: inaccurateness and relatively slow response. Additionally, the developed system can be implemented in a practical way at a low cost, which means an added value. The system also shows an excellent behavior for very fast variables in incident radiation levels. (author)
Study on Two Optimization Problems: Line Cover and Maximum Genus Embedding
Cao, Cheng
2012-07-16T23:59:59.000Z
programming duality. We de ne a new problem called Non-collinear Packing Problem (NPP) as the following: De nition B.1. Non-collinear Packing Problem Given a set P of n points on the Euclidean plane R2, nd a maximum subset S P of non-collinear points, i....e. any three points are not collinear. Before proving the duality between NPP and LCP, we need to show how to formulate both problems to linear programming. To formulate the form of linear pro- gramming for instances of LCP and NNP, we use a few...
Application of Maximum Entropy Method to Lattice Field Theory with a Topological Term
M. Imachi; Y. Shinno; H. Yoneyama
2003-09-22T23:59:59.000Z
In Monte Carlo simulation, lattice field theory with a $\\theta$ term suffers from the sign problem. This problem can be circumvented by Fourier-transforming the topological charge distribution $P(Q)$. Although this strategy works well for small lattice volume, effect of errors of $P(Q)$ becomes serious with increasing volume and prevents one from studying the phase structure. This is called flattening. As an alternative approach, we apply the maximum entropy method (MEM) to the Gaussian $P(Q)$. It is found that the flattening could be much improved by use of the MEM.
Conditional maximum-entropy method for selecting prior distributions in Bayesian statistics
Abe, Sumiyoshi
2014-01-01T23:59:59.000Z
The conditional maximum-entropy method (abbreviated here as C-MaxEnt) is formulated for selecting prior probability distributions in Bayesian statistics for parameter estimation. This method is inspired by a statistical-mechanical approach to systems governed by dynamics with largely-separated time scales and is based on three key concepts: conjugate pairs of variables, dimensionless integration measures with coarse-graining factors and partial maximization of the joint entropy. The method enables one to calculate a prior purely from a likelihood in a simple way. It is shown in particular how it not only yields Jeffreys's rules but also reveals new structures hidden behind them.
Charmonium spectra at finite temperature from QCD sum rules with the maximum entropy method
Philipp Gubler; Kenji Morita; Makoto Oka
2011-08-30T23:59:59.000Z
Charmonia spectral functions at finite temperature are studied using QCD sum rules in combination with the maximum entropy method. This approach enables us to directly obtain the spectral function from the sum rules, without having to introduce any specific assumption about its functional form. As a result, it is found that while J/psi and eta_c manifest themselves as significant peaks in the spectral function below the deconfinement temperature T_c, they quickly dissolve into the continuum and almost completely disappear at temperatures between 1.0 T_c and 1.1 T_c.
H. Rudolf Fiebig
2002-10-31T23:59:59.000Z
We study various aspects of extracting spectral information from time correlation functions of lattice QCD by means of Bayesian inference with an entropic prior, the maximum entropy method (MEM). Correlator functions of a heavy-light meson-meson system serve as a repository for lattice data with diverse statistical quality. Attention is given to spectral mass density functions, inferred from the data, and their dependence on the parameters of the MEM. We propose to employ simulated annealing, or cooling, to solve the Bayesian inference problem, and discuss practical issues of the approach.
Maximum Entropy and the Stress Distribution in Soft Disk Packings Above Jamming
Yegang Wu; S. Teitel
2014-10-17T23:59:59.000Z
We show that the maximum entropy hypothesis can successfully explain the distribution of stresses on compact clusters of particles within disordered mechanically stable packings of soft, isotropically stressed, frictionless disks above the jamming transition. We show that, in our two dimensional case, it becomes necessary to consider not only the stress but also the Maxwell-Cremona force-tile area, as a constraining variable that determines the stress distribution. The importance of the force-tile area was suggested by earlier computations on an idealized force-network ensemble.
Spectral Functions, Maximum Entropy Method and Unconventional Methods in Lattice Field Theory
Chris Allton; Danielle Blythe; Jonathan Clowser
2002-04-26T23:59:59.000Z
We present two unconventional methods of extracting information from hadronic 2-point functions produced by Monte Carlo simulations. The first is an extension of earlier work by Leinweber which combines a QCD Sum Rule approach with lattice data. The second uses the Maximum Entropy Method to invert the 2-point data to obtain estimates of the spectral function. The first approach is applied to QCD data, and the second method is applied to the Nambu--Jona-Lasinio model in (2+1)D. Both methods promise to augment the current approach where physical quantities are extracted by fitting to pure exponentials.
On Weyl channels being covariant with respect to the maximum commutative group of unitaries
Amosov, Grigori G. [Department of Higher Mathematics, Moscow Institute of Physics and Technology, Dolgoprudny 141700 (Russian Federation)
2007-01-15T23:59:59.000Z
We investigate the Weyl channels being covariant with respect to the maximum commutative group of unitary operators. This class includes the quantum depolarizing channel and the 'two-Pauli' channel as well. Then, we show that our estimation of the output entropy for a tensor product of the phase damping channel and the identity channel based upon the decreasing property of the relative entropy allows to prove the additivity conjecture for the minimal output entropy for the quantum depolarizing channel in any prime dimension and for the two-Pauli channel in the qubit case.
Maximum entropy analysis of hadron spectral functions and excited states in quenched lattice QCD
CP-PACS Collaboration; :; S. Aoki; R. Burkhalter; M. Fukugita; S. Hashimoto; N. Ishizuka; Y. Iwasaki; K. Kanaya; T. Kaneko; Y. Kuramashi; M. Okawa; Y. Taniguchi; A. Ukawa; T. Yamazaki; T. Yoshié
2001-10-16T23:59:59.000Z
Employing the maximum entropy method we extract the spectral functions from meson correlators at four lattice spacings in quenched QCD with the Wilson quark action. We confirm that the masses and decay constants, obtained from the position and the area of peaks, agree well with the results from the conventional exponential fit. For the first excited state, we obtain $m_{\\pi_1} = 660(590)$ MeV, $m_{\\rho_1} = 1540(570)$ MeV, and $f_{\\rho_1} = 0.085(36)$ in the continuum limit.
The ACT{sup 2} project: Demonstration of maximum energy efficiency in real buildings
Crawley, D.B. [Pacific Northwest Lab., Richland, WA (United States); Krieg, B.L. [Pacific Gas and Electric Co., San Ramon, CA (United States)
1991-11-01T23:59:59.000Z
A large US utility recently began a project to determine whether the use of new energy-efficient end-use technologies and systems would economically achieve substantial energy savings (perhaps as high as 75% over current practice). Using a field-based demonstration approach, the Advanced Customer Technology Test (ACT{sup 2}) for Maximum Energy Efficiency is providing information on the maximum energy savings possible when integrated packages of new high-efficiency end-use technologies are incorporated into commercial and residential buildings and industrial and agricultural processes. This paper details the underlying rationale, approach, results to date, and future plans for ACT{sup 2}. The ultimate goal is energy efficiency (doing more with less energy) rather than energy conservation (freezing in the dark). In this paper, we first explain why a major United States utility is committed to pursuing demand-side management so aggressively. Next, we discuss the approach the utility chose for conducting the ACT{sup 2} project. We then review results obtained to date from the project`s pilot demonstration site. Last, we describe other related demonstration projects being proposed by the utility.
The ACT sup 2 project: Demonstration of maximum energy efficiency in real buildings
Crawley, D.B. (Pacific Northwest Lab., Richland, WA (United States)); Krieg, B.L. (Pacific Gas and Electric Co., San Ramon, CA (United States))
1991-11-01T23:59:59.000Z
A large US utility recently began a project to determine whether the use of new energy-efficient end-use technologies and systems would economically achieve substantial energy savings (perhaps as high as 75% over current practice). Using a field-based demonstration approach, the Advanced Customer Technology Test (ACT{sup 2}) for Maximum Energy Efficiency is providing information on the maximum energy savings possible when integrated packages of new high-efficiency end-use technologies are incorporated into commercial and residential buildings and industrial and agricultural processes. This paper details the underlying rationale, approach, results to date, and future plans for ACT{sup 2}. The ultimate goal is energy efficiency (doing more with less energy) rather than energy conservation (freezing in the dark). In this paper, we first explain why a major United States utility is committed to pursuing demand-side management so aggressively. Next, we discuss the approach the utility chose for conducting the ACT{sup 2} project. We then review results obtained to date from the project's pilot demonstration site. Last, we describe other related demonstration projects being proposed by the utility.
Variable Selection for Modeling the Absolute Magnitude at Maximum of Type Ia Supernovae
Uemura, Makoto; Kawabata, S; Ikeda, Shiro; Maeda, Keiichi
2015-01-01T23:59:59.000Z
We discuss what is an appropriate set of explanatory variables in order to predict the absolute magnitude at the maximum of Type Ia supernovae. In order to have a good prediction, the error for future data, which is called the "generalization error," should be small. We use cross-validation in order to control the generalization error and LASSO-type estimator in order to choose the set of variables. This approach can be used even in the case that the number of samples is smaller than the number of candidate variables. We studied the Berkeley supernova database with our approach. Candidates of the explanatory variables include normalized spectral data, variables about lines, and previously proposed flux-ratios, as well as the color and light-curve widths. As a result, we confirmed the past understanding about Type Ia supernova: i) The absolute magnitude at maximum depends on the color and light-curve width. ii) The light-curve width depends on the strength of Si II. Recent studies have suggested to add more va...
Quantifying extrinsic noise in gene expression using the maximum entropy framework
Purushottam D. Dixit
2013-04-04T23:59:59.000Z
We present a maximum entropy framework to separate intrinsic and extrinsic contributions to noisy gene expression solely from the profile of expression. We express the experimentally accessible probability distribution of the copy number of the gene product (mRNA or protein) by accounting for possible variations in extrinsic factors. The distribution of extrinsic factors is estimated using the maximum entropy principle. Our results show that extrinsic factors qualitatively and quantitatively affect the probability distribution of the gene product. We work out, in detail, the transcription of mRNA from a constitutively expressed promoter in {\\it E. coli}. We suggest that the variation in extrinsic factors may account for the observed {\\it wider than Poisson} distribution of mRNA copy numbers. We successfully test our framework on a numerical simulation of a simple gene expression scheme that accounts for the variation in extrinsic factors. We also make falsifiable predictions, some of which are tested on previous experiments in {\\it E. coli} while others need verification. Application of the current framework to more complex situations is also discussed.
Trovato, M. [Dipartimento di Matematica, Universita di Catania, Viale A. Doria, I-95125 Catania (Italy); Reggiani, L. [Dipartimento di Ingegneria dell' Innovazione and CNISM, Universita del Salento, Via Arnesano s/n, I-73100 Lecce (Italy)
2011-12-15T23:59:59.000Z
By introducing a quantum entropy functional of the reduced density matrix, the principle of quantum maximum entropy is asserted as fundamental principle of quantum statistical mechanics. Accordingly, we develop a comprehensive theoretical formalism to construct rigorously a closed quantum hydrodynamic transport within a Wigner function approach. The theoretical formalism is formulated in both thermodynamic equilibrium and nonequilibrium conditions, and the quantum contributions are obtained by only assuming that the Lagrange multipliers can be expanded in powers of ({h_bar}/2{pi}){sup 2}. In particular, by using an arbitrary number of moments, we prove that (1) on a macroscopic scale all nonlocal effects, compatible with the uncertainty principle, are imputable to high-order spatial derivatives, both of the numerical density n and of the effective temperature T; (2) the results available from the literature in the framework of both a quantum Boltzmann gas and a degenerate quantum Fermi gas are recovered as a particular case; (3) the statistics for the quantum Fermi and Bose gases at different levels of degeneracy are explicitly incorporated; (4) a set of relevant applications admitting exact analytical equations are explicitly given and discussed; (5) the quantum maximum entropy principle keeps full validity in the classical limit, when ({h_bar}/2{pi}){yields}0.
Murton, Mark; Bouchier, Francis A.; vanDongen, Dale T.; Mack, Thomas Kimball; Cutler, Robert Paul; Ross, Michael P.
2013-08-01T23:59:59.000Z
Although technological advances provide new capabilities to increase the robustness of security systems, they also potentially introduce new vulnerabilities. New capability sometimes requires new performance requirements. This paper outlines an approach to establishing a key performance requirement for an emerging intrusion detection sensor: the sensored net. Throughout the security industry, the commonly adopted standard for maximum opening size through barriers is a requirement based on square inches-typically 96 square inches. Unlike standard rigid opening, the dimensions of a flexible aperture are not fixed, but variable and conformable. It is demonstrably simple for a human intruder to move through a 96-square-inch opening that is conformable to the human body. The longstanding 96-square-inch requirement itself, though firmly embedded in policy and best practice, lacks a documented empirical basis. This analysis concluded that the traditional 96-square-inch standard for openings is insufficient for flexible openings that are conformable to the human body. Instead, a circumference standard is recommended for these newer types of sensored barriers. The recommended maximum circumference for a flexible opening should be no more than 26 inches, as measured on the inside of the netting material.
Bounds and phase diagram of efficiency at maximum power for tight-coupling molecular motors
Z. C. Tu
2013-02-08T23:59:59.000Z
The efficiency at maximum power (EMP) for tight-coupling molecular motors is investigated within the framework of irreversible thermodynamics. It is found that the EMP depends merely on the constitutive relation between the thermodynamic current and force. The motors are classified into four generic types (linear, superlinear, sublinear, and mixed types) according to the characteristics of the constitutive relation, and then the corresponding ranges of the EMP for these four types of molecular motors are obtained. The exact bounds of the EMP are derived and expressed as the explicit functions of the free energy released by the fuel in each motor step. A phase diagram is constructed which clearly shows how the region where the parameters (the load distribution factor and the free energy released by the fuel in each motor step) are located can determine whether the value of the EMP is larger or smaller than 1/2. This phase diagram reveals that motors using ATP as fuel under physiological conditions can work at maximum power with higher efficiency ($>1/2$) for a small load distribution factor ($<0.1$).
SPECTROSCOPIC OBSERVATIONS OF A CORONAL MORETON WAVE
Harra, Louise K. [UCL-Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom); Sterling, Alphonse C. [Space Science Office, VP62, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Goemoery, Peter [Astronomical Institute, Slovak Academy of Sciences, SK-05960 Tatranska Lomnica (Slovakia); Veronig, Astrid, E-mail: lkh@mssl.ucl.ac.uk, E-mail: alphonse.sterling@nasa.gov, E-mail: gomory@astro.s, E-mail: astrid.veronig@uni-graz.at [Institute of Physics, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria)
2011-08-10T23:59:59.000Z
We observed a coronal wave (EIT wave) on 2011 February 16, using EUV imaging data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) and EUV spectral data from the Hinode/EUV Imaging Spectrometer (EIS). The wave accompanied an M1.6 flare that produced a surge and a coronal mass ejection (CME). EIS data of the wave show a prominent redshifted signature indicating line-of-sight velocities of {approx}20 km s{sup -1} or greater. Following the main redshifted wave front, there is a low-velocity period (and perhaps slightly blueshifted), followed by a second redshift somewhat weaker than the first; this progression may be due to oscillations of the EUV atmosphere set in motion by the initial wave front, although alternative explanations may be possible. Along the direction of the EIS slit the wave front's velocity was {approx}500 km s{sup -1}, consistent with its apparent propagation velocity projected against the solar disk as measured in the AIA images, and the second redshifted feature had propagation velocities between {approx}200 and 500 km s{sup -1}. These findings are consistent with the observed wave being generated by the outgoing CME, as in the scenario for the classic Moreton wave. This type of detailed spectral study of coronal waves has hitherto been a challenge, but is now possible due to the availability of concurrent AIA and EIS data.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1DOETHE FUTURE LOOKS
On the breaking of a plasma wave in a thermal plasma. I. The structure of the density singularity
Bulanov, Sergei V.; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Pirozhkov, Alexander S.; Nakamura, Tatsufumi [QuBS, Japan Atomic Energy Agency, 1-8-7 Umemidai, Kizugawa, Kyoto 619-0215 (Japan); Bulanov, Stepan S. [University of California, Berkeley, California 94720 (United States); Schroeder, Carl B.; Esarey, Eric [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Califano, Francesco; Pegoraro, Francesco [Physics Department, University of Pisa, Pisa 56127 (Italy)
2012-11-15T23:59:59.000Z
The structure of the singularity that is formed in a relativistically large amplitude plasma wave close to the wave breaking limit is found by using a simple waterbag electron distribution function. The electron density distribution in the breaking wave has a typical 'peakon' form. The maximum value of the electric field in a thermal breaking plasma is obtained and compared to the cold plasma limit. The results of computer simulations for different initial electron distribution functions are in agreement with the theoretical conclusions. The after-wavebreak regime is then examined, and a semi-analytical model of the density evolution is constructed. Finally the results of two dimensional particle in cell simulations for different initial electron distribution functions are compared, and the role of thermal effects in enhancing particle injection is noted.
Wang, Yunliang, E-mail: ylwang@ustb.edu.cn; Lü, Xiaoxia [Department of Physics, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083 (China)] [Department of Physics, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083 (China)
2014-02-15T23:59:59.000Z
The modulational instability of quantum electrostatic acoustic waves in electron-hole quantum semiconductor plasmas is investigated using the quantum hydrodynamic model, from which a modified nonlinear Schrödinger equation with damping effects is derived using the reductive perturbation method. Here, we consider the combined effects of quantum recoil, quantum degenerate pressures, as well as the exchange-correlation effect standing for the electrons (holes) spin. The modulational instability for different semiconductors (GaAs, GaSb, and InP) is discussed. The collision between electron (hole) and phonon is also investigated. The permitted maximum time for modulational instability and the damping features of quantum envelope solitary wave are all determined by the collision. The approximate solitary solution with damping effects is presented in weak collision limit. The damping properties were discussed by numerical method.
Evidence for 2D Solitary Sound Waves in a Lipid Controlled Interface and its Biological Implications
Shamit Shrivastava; Matthias F. Schneider
2014-05-08T23:59:59.000Z
Biological membranes by virtue of their elastic properties should be capable of propagating localized perturbations analogous to sound waves. However, the existence and the possible role of such waves in communication in biology remains unexplored. Here we report the first observations of 2D solitary elastic pulses in lipid interfaces, excited mechanically and detected by FRET. We demonstrate that the nonlinearity near a maximum in the susceptibility of the lipid monolayer results in solitary pulses that also have a threshold for excitation. These experiments clearly demonstrate that the state of the interface regulates the propagation of pulses both qualitatively and quantitatively. We elaborate on the striking similarity of the observed phenomenon to nerve pulse propagation and a thermodynamic basis of cell signaling in general.
Li, Y.; Yu, Y.; Epler, J.; Previsic, M.
2012-04-01T23:59:59.000Z
The extraction of energy from ocean waves has gained interest in recent years. The floating-point absorber (FPA) is one of the most promising devices among a wide variety of wave energy conversion technologies. Early theoretical studies mainly focused on understanding the hydrodynamics of the system and on predicting the maximum power that could be extracted by a heaving body. These studies evolve from the investigation of floating-body interactions in offshore engineering and naval architecture disciplines. To our best knowledge, no systematic study has been reported about the investigation of the power generation performance of an FPA with a close-to-commercial design. A series of experimental tests was conducted to investigate the power extraction performance of an FPA system.
Attosecond electron pulses from interference of above-threshold de Broglie waves
Sandor Varro; Gyozo Farkas
2007-05-02T23:59:59.000Z
It is shown that the the interference of above-threshold electron de Broglie waves, generated by an intense laser pulse at a metal surface yields attosecond electron pulses. This inerference is an analogon of the superposition of high harmonics generated from rare gas atoms, resulting in trains of attosecond light pulses.Owing to the inherent kinematic dispersion, the propagation of attosecond de Broglie waves in vacuum is very different from that of attosecond light pulses, which propagate without changing shape. Above the metal surface there are "collaps bands" and "revival layers" of the electron current even at macroscopic distances. In the range of parameters considered, the maximum value of the current densities of such ultrashort electron pulses has been estimated to be of order of couple of tenths of milliamps per square centimeters.
Quantum versus classical descriptions of sub-Poissonian light generation in three-wave mixing
Jiri Bajer; Adam Miranowicz
2001-07-20T23:59:59.000Z
Sub-Poissonian light generation in the non-degenerate three-wave mixing is studied numerically and analytically within quantum and classical approaches. Husimi Q-functions and their classical trajectory simulations are analysed to reveal a special regime corresponding to the time-stable sub-Poissonian photocount statistics of the sum-frequency mode. Conditions for observation of this regime are discussed. Theoretical predictions of the Fano factor and explanation of the extraordinary stabilization of the sub-Poissonian photocount behavior are obtained analytically by applying the classical trajectories. Scaling laws for the maximum sub-Poissonian behavior are found. Noise suppression levels in the non-degenerate vs degenerate three-wave mixing are discussed on different time scales compared to the revival times. It is shown that the non-degenerate conversion offers much better stabilization of the suppressed noise in comparison to that of degenerate process.
Comment on "Mode Conversion of Waves In The Ion-Cyclotron Frequency Range in Magnetospheric Plasmas"
Kim, Eun
2014-02-28T23:59:59.000Z
Recently, Kazakov and Fulop [1] studied mode conversion (MC) at the ion-ion hybrid (IIH) resonance in planetary magnetospheric plasmas by simplifying the dispersion relation of the fast wave (FW) modes to describe a cutoff-resonance (CR) pair near the IIH resonance, which can be reduced to a Budden problem. They suggested that when the IIH resonance frequency (?S) approaches the crossover frequency (?cr), and the parallel wavenumber (k?) is close to the critical wavenumber k? ?(?S = ?cr), MC can be efficient for arbitrary heavy ion density ratios. In this Comment, we argue that (a) the FW dispersion relation cannot be simplified to the CR pair especially near ?cr because in many parameter regimes there is a cutoff-resonance-cutoff (CRC) triplet that completely changes the wave absorption; and (b) the maximum MC efficiency does not always occur near k? ?#25; k???.
Anomalous absorption of bulk shear sagittal acoustic waves in a layered structure with viscous fluid
Dmitri K. Gramotnev; Melissa L. Mather; Timo A. Nieminen
2005-09-05T23:59:59.000Z
It is demonstrated theoretically that the absorptivity of bulk shear sagittal waves by an ultra-thin layer of viscous fluid between two different elastic media has a strong maximum (in some cases as good as 100%) at an optimal layer thickness. This thickness is usually much smaller than the penetration depths and lengths of transverse and longitudinal waves in the fluid. The angular dependencies of the absorptivity are demonstrated to have significant and unusual structure near critical angles of incidence. The effect of non-Newtonian properties and non-uniformities of the fluid layer on the absorptivity is also investigated. In particular, it is shown that the absorption in a thin layer of viscous fluid is much more sensitive to non-zero relaxation time(s) in the fluid layer than the absorption at an isolated solid-fluid interface.
Tsoflias, Georgios P.; Hoch, Anthony
2006-10-18T23:59:59.000Z
. Therefore, we constructed the model consisting of layers of air, allowing maximum control of antenna positioning, and polycarbonate, a medium nearly transparent to radar waves (relative permit- tivity er = 3, electrical conductivity s = 1mS/m). The vertical... thin layer was simulated by the space between two 1.22 #1; 2.44 m (4 #1; 8 foot), 12.7 mm (0.5 inch) thick sheets of polycarbonate. The space between the polycarbonate sheets was set to 1.6 mm (1/16 inch) and 4.8 mm (3/16 inch) to simulate different...
Three-Dimensional Momentum Imaging of Electron Wave Packet Interference in Few-Cycle Laser Pulses
Gopal, R.; Simeonidis, K.; Moshammer, R.; Ergler, Th.; Duerr, M.; Kurka, M.; Kuehnel, K.-U.; Tschuch, S.; Schroeter, C.-D.; Bauer, D.; Ullrich, J.; Rudenko, A.; Herrwerth, O.; Uphues, Th.; Schultze, M.; Goulielmakis, E.; Uiberacker, M.; Lezius, M.; Kling, M. F. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Max-Planck Advanced Study Group at CFEL, D-22607 Hamburg (Germany); Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany)
2009-07-31T23:59:59.000Z
Using a reaction microscope, three-dimensional (3D) electron (and ion) momentum (P) spectra have been recorded for carrier-envelope-phase (CEP) stabilized few-cycle (approx5 fs), intense (approx4x10{sup 14} W/cm{sup 2}) laser pulses (740 nm) impinging on He. Preferential emission of low-energy electrons (E{sub e}<15 eV) to either hemisphere is observed as a function of the CEP. Clear interference patterns emerge in P space at CEPs with maximum asymmetry, interpreted as attosecond interferences of rescattered and directly emitted electron wave packets by means of a simple model.
Detection of azimuthal anisotropy from 3-D p-wave seismic data
Yildizel, Ali
1992-01-01T23:59:59.000Z
the equation; (II ? 1) for u(z) = V t(z) is wave slowness. Velocity estimation using reflections and the tau-p approach was first suggested by Schultz and Claerbout (1978), They showed that velocity analysis can be done in a ' similar manner... to conventional analysis by looking for maximum coherency over each ' trajectory of ellipses in r-p domain instead of a hyperbola in conventional analysis. Schultz (1982) also suggested a method of layer-stripping for velocity estimation in the r-p domain...
The Loudest Gravitational Wave Events
Hsin-Yu Chen; Daniel E. Holz
2014-09-04T23:59:59.000Z
As first emphasized by Bernard Schutz, there exists a universal distribution of signal-to-noise ratios for gravitational wave detection. Because gravitational waves (GWs) are almost impossible to obscure via dust absorption or other astrophysical processes, the strength of the detected signal is dictated solely by the emission strength and the distance to the source. Assuming that the space density of an arbitrary population of GW sources does not evolve, we show explicitly that the distribution of detected signal-to-noise (SNR) values depends solely on the detection threshold; it is independent of the detector network (interferometer or pulsar timing array), the individual detector noise curves (initial or Advanced LIGO), the nature of the GW sources (compact binary coalescence, supernova, or some other discrete source), and the distributions of source variables (only non-spinning neutron stars of mass exactly $1.4\\,M_\\odot$ or a complicated distribution of masses and spins). We derive the SNR distribution for each individual detector within a network as a function of the relative detector orientations and sensitivities. While most detections will have SNR near the detection threshold, there will be a tail of events to higher SNR. We derive the SNR distribution of the loudest (highest SNR) events in any given sample of detections. We find that the median SNR of the loudest out of the first four events should have an $\\mbox{SNR}=22$ (for a threshold of 12, appropriate for the Advanced LIGO/Virgo network), increasing to a median value for the loudest SNR of 47 for 40 detections. We expect these loudest events to provide particularly powerful constraints on their source parameters, and they will play an important role in extracting astrophysics from gravitational wave sources. These distributions also offer an important internal calibration of the response of the GW detector networks.
Particle acceleration in superluminal strong waves
Teraki, Yuto; Nagataki, Shigehiro
2015-01-01T23:59:59.000Z
We calculate the electron acceleration in random superluminal strong waves (SLSWs) and radiation from them by using numerical methods in the context of the termination shock of the pulsar wind nebulae. We pursue the electrons by solving the equation of motion in the analytically expressed electromagnetic turbulences. These consist of primary SLSW and isotropically distributed secondary electromagnetic waves. Under the dominance of the secondary waves, all electrons gain nearly equal energy. On the other hand, when the primary wave is dominant, selective acceleration occurs. The phase of the primary wave felt by the electrons moving nearly along the wavevector changes very slowly compared to the oscillation of the wave, which is called "phase locked", and such electrons are continuously accelerated. This acceleration by SLSWs may play a crucial role in the pre-acceleration for the shock acceleration. In general, the radiation from the phase-locked population is different from the synchro-Compton radiation. How...
Wave Heating of the Solar Atmosphere
Arregui, I
2015-01-01T23:59:59.000Z
Magnetic waves are a relevant component in the dynamics of the solar atmosphere. Their significance has increased because of their potential as a remote diagnostic tool and their presumed contribution to plasma heating processes. We discuss our current understanding on coronal heating by magnetic waves, based on recent observational evidence and theoretical advances. The discussion starts with a selection of observational discoveries that have brought magnetic waves to the forefront of the coronal heating discussion. Then, our theoretical understanding on the nature and properties of the observed waves and the physical processes that have been proposed to explain observations are described. Particular attention is given to the sequence of processes that link observed wave characteristics with concealed energy transport, dissipation, and heat conversion. We conclude with a commentary on how the combination of theory and observations should help us understanding and quantifying magnetic wave heating of the sola...
Refrigeration system having standing wave compressor
Lucas, Timothy S. (Glen Allen, VA)
1992-01-01T23:59:59.000Z
A compression-evaporation refrigeration system, wherein gaseous compression of the refrigerant is provided by a standing wave compressor. The standing wave compressor is modified so as to provide a separate subcooling system for the refrigerant, so that efficiency losses due to flashing are reduced. Subcooling occurs when heat exchange is provided between the refrigerant and a heat pumping surface, which is exposed to the standing acoustic wave within the standing wave compressor. A variable capacity and variable discharge pressure for the standing wave compressor is provided. A control circuit simultaneously varies the capacity and discharge pressure in response to changing operating conditions, thereby maintaining the minimum discharge pressure needed for condensation to occur at any time. Thus, the power consumption of the standing wave compressor is reduced and system efficiency is improved.
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin BaxinUmweltVillageGraph HomeWaranaWater Power ForumGeothermalWave
Elgen Wave | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489 No revision| OpenElectromagnetic ProfilingElgen Wave Jump to:
Long-range propagation of ocean waves
Young, William R.
hours. Friday, February 22, 2013 #12;OceanPowerTechnologies A 103 foot long, 260ton buoy being tested #12;Wave Power? PelamisWavePower With T=10sec and a = 1 meter, the energy flux is 40kW/meter. An average 40kW/meter of wave power is typical of good sites. Energy Flux = cg × Energy Density = g2 Ta2 8
Irregular wave induced velocities in shallow water
Sultan, Nels John
1991-01-01T23:59:59.000Z
probabil- ity density function. This thesis applies this expanded distribution to fluid particle velocities instead of wave elevations. Ochi (1982) presents a review of recent ad- vances in the stochastic analysis of random seas. He notes that the first..., (Longuet-Higgins 1963), that purely linear waves will have a Gaussian distribu- tion. Therefore, any deviation from a Gaussian distribution must be attributed to wave nonlinearities. Ochi (1982) discusses a series of experiments by Honda and Mitsuyasu...
Li, Bin
2012-11-29T23:59:59.000Z
Most designs for wave energy converters include a hydraulic (or pneumatic) interface between the wave device and the generator to smooth electricity production, but a direct drive power take-off system is a possible way ...
Full-wave modeling of lower hybrid waves on Alcator C-Mod
Meneghini, Orso (Orso-Maria Cornelio)
2012-01-01T23:59:59.000Z
This thesis focuses on several aspects of the Lower Hybrid (LH) wave physics, the common theme being the development of full-wave simulation codes based on Finite Element Methods (FEM) used in support of experiments carried ...
Using a Bore-Soliton-Splash to understand Rogue Waves, Tsunamis & Wave Energy
Wirosoetisno, Djoko
)compression] use wave focussing in a convergence [3]. · IPS wave buoy has a linear dynamo below sea level. · Designed & built new RogueWavEnergy device: it works, a LED is blinking & we measured the power output. 8
Interaction of gravitational waves with matter
A. Cetoli; C. J. Pethick
2011-10-03T23:59:59.000Z
We develop a unified formalism for describing the interaction of gravitational waves with matter that clearly separates the effects of general relativity from those due to interactions in the matter. Using it, we derive a general expression for the dispersion of gravitational waves in matter in terms of correlation functions for the matter in flat spacetime. The self energy of a gravitational wave is shown to have contributions analogous to the paramagnetic and diamagnetic contributions to the self energy of an electromagnetic wave. We apply the formalism to some simple systems - free particles, an interacting scalar field, and a fermionic superfluid.
Elastic Wave Behavior Across Linear Slip Interfaces
Schoenberg, M.
plane waves incident at arbitrary angles upon a plane linear slip interface are computed ... Also included in these sections is an analysis ... ish, Ut is of the form.
Nonlinear manipulation and control of matter waves
E. V. Goldstein; M. G. Moore; P. Meystre
1999-06-23T23:59:59.000Z
This paper reviews some of our recent results in nonlinear atom optics. In addition to nonlinear wave-mixing between matter waves, we also discuss the dynamical interplay between optical and matter waves. This new paradigm, which is now within experimental reach, has the potential to impact a number of fields of physics, including the manipulation and applications of atomic coherence, and the preparation of quantum entanglement between microscopic and macroscopic systems. Possible applications include quantum information processing, matter-wave holography, and nanofabrication.
Wave Propagation in Fractured Poroelastic Media
2014-06-22T23:59:59.000Z
Wave Propagation in Fractured. Poroelastic Media. WCCM, Barcelona, Spain, July 2014. Juan E. Santos,. 1. 1. Instituto del Gas y del Petr´oleo (IGPUBA), UBA,
Sandia National Laboratories: wave energy converter
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
release. This model has ... Sandia Funded to Model Power Pods for Utility-Scale Wave-Energy Converter On September 16, 2014, in Computational Modeling & Simulation, Energy,...
Stochastic Quantum Trajectories without a Wave Function
Jeroen C. Vink
2015-03-16T23:59:59.000Z
After summarizing three versions of trajectory-based quantum mechanics, it is argued that only the original formulation due to Bohm, which uses the Schr\\"odinger wave function to guide the particles, can be readily extended to particles with spin. To extend the two wave function-free formulations, it is argued that necessarily particle trajectories not only determine location, but also spin. Since spin values are discrete, it is natural to revert to a variation of Bohm's pilot wave formulation due originally to Bell. It is shown that within this formulation with stochastic quantum trajectories, a wave function free formulation can be obtained.
Sandia National Laboratories: reflected optical wave
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
reflected optical wave New Sandia Mirror Isn't Shiny: Instead It Reflects Infrared Light Using a Metamaterial On December 12, 2014, in Capabilities, Materials Science, News, News &...
Wave Packets Propagation in Quantum Gravity
Kourosh Nozari; S. H. Mehdipour
2005-07-03T23:59:59.000Z
Wave packet broadening in usual quantum mechanics is a consequence of dispersion behavior of the medium which the wave propagates in it. In this paper, we consider the problem of wave packet broadening in the framework of Generalized Uncertainty Principle(GUP) of quantum gravity. New dispersion relations are derived in the context of GUP and it has been shown that there exists a gravitational induced dispersion which leads to more broadening of the wave packets. As a result of these dispersion relations, a generalized Klein-Gordon equation is obtained and its interpretation is given.
Fast methods for inverse wave scattering problems
Lee, Jung Hoon, Ph. D. Massachusetts Institute of Technology
2008-01-01T23:59:59.000Z
Inverse wave scattering problems arise in many applications including computerized/diffraction tomography, seismology, diffraction/holographic grating design, object identification from radar singals, and semiconductor ...
Experiment Indicates Sound Waves Can Trigger Quakes
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
in a laboratory setting, a Los Alamos researcher and his colleagues have shown that seismic waves-the sounds radiated from earthquakes-can induce earthquake aftershocks, often...
Sandia National Laboratories: wave energy converters
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
marine hydrokinetic (MHK) reference models (RMs) for wave energy converters and tidal, ocean, and river current energy converters. The RMP team includes a partnership between...
G. Litak; T. Kaminski; J. Czarnigowski; A. K. Sen; M. Wendeker
2006-11-29T23:59:59.000Z
In this paper we analyze the cycle-to-cycle variations of maximum pressure $p_{max}$ and peak pressure angle $\\alpha_{pmax}$ in a four-cylinder spark ignition engine. We examine the experimental time series of $p_{max}$ and $\\alpha_{pmax}$ for three different spark advance angles. Using standard statistical techniques such as return maps and histograms we show that depending on the spark advance angle, there are significant differences in the fluctuations of $p_{max}$ and $\\alpha_{pmax}$. We also calculate the multiscale entropy of the various time series to estimate the effect of randomness in these fluctuations. Finally, we explain how the information on both $p_{max}$ and $\\alpha_{pmax}$ can be used to develop optimal strategies for controlling the combustion process and improving engine performance.
Kempes, Christopher P; Dooris, William; West, Geoffrey B
2015-01-01T23:59:59.000Z
In the face of uncertain biological response to climate change and the many critiques concerning model complexity it is increasingly important to develop predictive mechanistic frameworks that capture the dominant features of ecological communities and their dependencies on environmental factors. This is particularly important for critical global processes such as biomass changes, carbon export, and biogenic climate feedback. Past efforts have successfully understood a broad spectrum of plant and community traits across a range of biological diversity and body size, including tree size distributions and maximum tree height, from mechanical, hydrodynamic, and resource constraints. Recently it was shown that global scaling relationships for net primary productivity are correlated with local meteorology and the overall biomass density within a forest. Along with previous efforts, this highlights the connection between widely observed allometric relationships and predictive ecology. An emerging goal of ecological...
Role of ocean-atmosphere interactions in tropical cooling during the last glacial maximum
Bush, A.B.G. [Univ. of Alberta, Edmonton (Canada)] [Univ. of Alberta, Edmonton (Canada); Philander, S.G.H. [Princeton Univ., NJ (United States)] [Princeton Univ., NJ (United States)
1998-02-27T23:59:59.000Z
A simulation with a coupled atmosphere-ocean general circulation model configured for the Last Glacial Maximum delivered a tropical climate that is much cooler than that produced by atmosphere-only models. The main reason is a decrease in tropical sea surface temperatures, up to 6{degree}C in the western tropical Pacific, which occurs because of two processes. The trade winds induce equatorial upwelling and zonal advection of cold water that further intensify the trade winds, and an exchange of water occurs between the tropical and extratropical Pacific in which the poleward surface flow is balanced by equatorward flow of cold water in the thermocline. Simulated tropical temperature depressions are of the same magnitude as those that have been proposed from recent proxy data. 25 refs., 4 figs.
A. Vaudrey; P. Baucour; F. Lanzetta; R. Glises
2010-08-30T23:59:59.000Z
Producing useful electrical work in consuming chemical energy, the fuel cell have to reject heat to its surrounding. However, as it occurs for any other type of engine, this thermal energy cannot be exchanged in an isothermal way in finite time through finite areas. As it was already done for various types of systems, we study the fuel cell within the finite time thermodynamics framework and define an endoreversible fuel cell. Considering different types of heat transfer laws, we obtain an optimal value of the operating temperature, corresponding to a maximum produced power. This analysis is a first step of a thermodynamical approach of design of thermal management devices, taking into account performances of the whole system.
Vaudrey, A; Lanzetta, F; Glises, R
2009-01-01T23:59:59.000Z
Producing useful electrical work in consuming chemical energy, the fuel cell have to reject heat to its surrounding. However, as it occurs for any other type of engine, this thermal energy cannot be exchanged in an isothermal way in finite time through finite areas. As it was already done for various types of systems, we study the fuel cell within the finite time thermodynamics framework and define an endoreversible fuel cell. Considering different types of heat transfer laws, we obtain an optimal value of the operating temperature, corresponding to a maximum produced power. This analysis is a first step of a thermodynamical approach of design of thermal management devices, taking into account performances of the whole system.
From Physics to Economics: An Econometric Example Using Maximum Relative Entropy
Giffin, Adom
2009-01-01T23:59:59.000Z
Econophysics, is based on the premise that some ideas and methods from physics can be applied to economic situations. We intend to show in this paper how a physics concept such as entropy can be applied to an economic problem. In so doing, we demonstrate how information in the form of observable data and moment constraints are introduced into the method of Maximum relative Entropy (MrE). A general example of updating with data and moments is shown. Two specific econometric examples are solved in detail which can then be used as templates for real world problems. A numerical example is compared to a large deviation solution which illustrates some of the advantages of the MrE method.
Reginatto, Marcel; Zimbal, Andreas [Physikalisch-Technische Bundesanstalt, 38116 Braunschweig (Germany)
2008-02-15T23:59:59.000Z
In applications of neutron spectrometry to fusion diagnostics, it is advantageous to use methods of data analysis which can extract information from the spectrum that is directly related to the parameters of interest that describe the plasma. We present here methods of data analysis which were developed with this goal in mind, and which were applied to spectrometric measurements made with an organic liquid scintillation detector (type NE213). In our approach, we combine Bayesian parameter estimation methods and unfolding methods based on the maximum entropy principle. This two-step method allows us to optimize the analysis of the data depending on the type of information that we want to extract from the measurements. To illustrate these methods, we analyze neutron measurements made at the PTB accelerator under controlled conditions, using accelerator-produced neutron beams. Although the methods have been chosen with a specific application in mind, they are general enough to be useful for many other types of measurements.
Maximum Achievable Control Technology for New Industrial Boilers (released in AEO2005)
Reports and Publications (EIA)
2005-01-01T23:59:59.000Z
As part of Clean Air Act 90 (CAAA90, the EPA on February 26, 2004, issued a final rulethe National Emission Standards for Hazardous Air Pollutants (NESHAP) to reduce emissions of hazardous air pollutants (HAPs) from industrial, commercial, and institutional boilers and process heaters. The rule requires industrial boilers and process heaters to meet limits on HAP emissions to comply with a Maximum Achievable Control Technology (MACT) floor level of control that is the minimum level such sources must meet to comply with the rule. The major HAPs to be reduced are hydrochloric acid, hydrofluoric acid, arsenic, beryllium, cadmium, and nickel. The EPA predicts that the boiler MACT rule will reduce those HAP emissions from existing sources by about 59,000 tons per year in 2005.
Urniezius, Renaldas [Kaunas University of Technology, Kaunas (Lithuania)
2011-03-14T23:59:59.000Z
The principle of Maximum relative Entropy optimization was analyzed for dead reckoning localization of a rigid body when observation data of two attached accelerometers was collected. Model constraints were derived from the relationships between the sensors. The experiment's results confirmed that accelerometers each axis' noise can be successfully filtered utilizing dependency between channels and the dependency between time series data. Dependency between channels was used for a priori calculation, and a posteriori distribution was derived utilizing dependency between time series data. There was revisited data of autocalibration experiment by removing the initial assumption that instantaneous rotation axis of a rigid body was known. Performance results confirmed that such an approach could be used for online dead reckoning localization.
Azimuthal Anisotropy in Heavy Ion Collisions from the Maximum Entropy Method
Pirner, Hans J
2014-01-01T23:59:59.000Z
We investigate the azimuthal anisotropy v2 of particle production in nucleus-nucleus collisions in the maximum entropy approach. This necessitates two new parameters delta and lambda2. The parameter delta describes the deformation of transverse configuration space and is related to the anisotropy of the overlap zone of the two nuclei. The parameter lambda2 defines the anisotropy of the particle distribution in momentum space. Assuming deformed flux tubes at the early stage of the collision we relate the momentum to the space asymmetry i.e. lambda2 to delta with the uncertainty relation. We compute the anisotropy v2 as a function of centrality, transverse momentum and rapidity using gluon-hadron duality. The general features of LHC data are reproduced.